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Sample records for igpp-lanl teoloyucan teo

  1. Analysis of the ULF electromagnetic emission related to seismic activity, Teoloyucan geomagnetic station, 1998-2001

    Directory of Open Access Journals (Sweden)

    A. Kotsarenko

    2004-01-01

    Full Text Available Results of ULF geomagnetic measurements at station Teoloyucan (Central Mexico, 99.11'35.735''W, 19.44'45.100''N, 2280m height in relation to seismic activity in the period 1998-2001 and their analysis are presented. Variations of spectral densities for horizontal and vertical components, polarization densities and spectrograms of magnetic field, their derivatives are analyzed as a part of traditional analysis in this study. Values of spectral density were calculated for 6 fixed frequencies f=1, 3, 10, 30, 100 and 300mHz. Fractal characteristics of spectra were analyzed in the conception of SOC (Self-Organized Criticality. 2 nighttime intervals, 0-3 and 3-6h by local time have been used to decrease the noise interference in row data. In order to exclude the intervals with a high geomagnetic activity from analysis we referred to Ap indices, calculated for corresponding time intervals. The contribution of seismic events to geomagnetic emission was estimated by seismic index ks=100.75Ms/10D, where Ms is the amplitude of the earthquake and D is the distance from its epicenter to the station.

  2. Possible seismogenic origin of changes in the ULF EM resonant structure observed at Teoloyucan geomagnetic station, Mexico, 1999-2001

    Directory of Open Access Journals (Sweden)

    A. Kotsarenko

    2005-01-01

    Full Text Available The evolution of the ULF resonant structure observed at Teoloyucan geomagnetic station has been provisionally studied in a possible relation with seismic activity in Mexico in the period 1999-2001. Two resonant lines were observed in the H-component (linear polarization in the frequency bands fR2=10.2–11.1 mHz and fR2=13.6–14.5 mHz, sometimes accompanied by other harmonics. The source of the observed resonances is possibly related with the geomagnetic location of the station (geomagnetic latitude λ=29.1° and its proximity to the equatorial electrojet (λ~30°. An enhancement of the carrier frequency of both resonances in the period 1 month–2 weeks was found before the strongest EQs. Also, a depression of the resonant structure just a few days before and a few days after some EQs seems to be correlated with seismic activity.

  3. TEO LT hakkab kaotama atraktiivsust / Romet Kreek

    Index Scriptorium Estoniae

    Kreek, Romet, 1972-

    2011-01-01

    Autori sõnul on Leedu telekomiettevõtte TEO LT puhul raske oodata, et käive ja kasum kasvaksid, parimal juhul on need stabiilsed. Osalt on selle põhjuseks tehnoloogilised muutused, osalt suuromaniku poliitika. TEO LT I kvartali majandusnäitajatest

  4. Ca teos report in register N 13377

    International Nuclear Information System (INIS)

    Pena, S; Arrighetti, R.

    2011-01-01

    This work is about a report about ca teos carried out in register N 13377 in the department of Canelones to know the depth of the field. The drilling done allowed to identify granite and clay. This granite outcrops are developed in the east of the middle course of the stream Pando

  5. Zn2(TeO3Br2

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    Mats Johnsson

    2008-05-01

    Full Text Available Single crystals of dizinc tellurium dibromide trioxide, Zn2(TeO3Br2, were synthesized via a transport reaction in sealed evacuated silica tubes. The compound has a layered crystal structure in which the building units are [ZnO4Br] distorted square pyramids, [ZnO2Br2] distorted tetrahedra, and [TeO3E] tetrahedra (E being the 5s2 lone pair of Te4+ joined through sharing of edges and corners to form layers of no net charge. Bromine atoms and tellurium lone pairs protrude from the surfaces of each layer towards adjacent layers. This new compound Zn2(TeO3Br2 is isostructural with the synthetic compounds Zn2(TeO3Cl2, CuZn(TeO32, Co2(TeO3Br2 and the mineral sophiite, Zn2(SeO3Cl2.

  6. Zn2(TeO3)Br2

    Science.gov (United States)

    Zhang, Dong; Johnsson, Mats

    2008-01-01

    Single crystals of dizinc tellurium dibromide trioxide, Zn2(TeO3)Br2, were synthesized via a transport reaction in sealed evacuated silica tubes. The compound has a layered crystal structure in which the building units are [ZnO4Br] distorted square pyramids, [ZnO2Br2] distorted tetra­hedra, and [TeO3 E] tetra­hedra (E being the 5s 2 lone pair of Te4+) joined through sharing of edges and corners to form layers of no net charge. Bromine atoms and tellurium lone pairs protrude from the surfaces of each layer towards adjacent layers. This new compound Zn2(TeO3)Br2 is isostructural with the synthetic compounds Zn2(TeO3)Cl2, CuZn(TeO3)2, Co2(TeO3)Br2 and the mineral sophiite, Zn2(SeO3)Cl2. PMID:21202162

  7. Electron collision cross section sets of TMS and TEOS vapours

    Science.gov (United States)

    Kawaguchi, S.; Takahashi, K.; Satoh, K.; Itoh, H.

    2017-05-01

    Reliable and detailed sets of electron collision cross sections for tetramethylsilane [TMS, Si(CH3)4] and tetraethoxysilane [TEOS, Si(OC2H5)4] vapours are proposed. The cross section sets of TMS and TEOS vapours include 16 and 20 kinds of partial ionization cross sections, respectively. Electron transport coefficients, such as electron drift velocity, ionization coefficient, and longitudinal diffusion coefficient, in those vapours are calculated by Monte Carlo simulations using the proposed cross section sets, and the validity of the sets is confirmed by comparing the calculated values of those transport coefficients with measured data. Furthermore, the calculated values of the ionization coefficient in TEOS/O2 mixtures are compared with measured data to confirm the validity of the proposed cross section set.

  8. TEO - vana rahamasin töötab ikka veel / Steffan Andersson

    Index Scriptorium Estoniae

    Andersson, Steffan

    2006-01-01

    Ülevaade Leedu kommunikatsioonifirma TEO (endine Leedu Telekom, praegu 60% mahus TeliaSonera tütarfirma) majandustegevusest ja aktsia hinnast. Graafik: TEO aktsia kurss 24. okt. 2005 - 24. okt. 2006

  9. Teo omistamine riigile rahvusvahelises õiguses : [bakalaureusetöö] / Kadri Paris ; Tartu Ülikool, õigusteaduskond ; juhendaja: Juhani Kortteinen

    Index Scriptorium Estoniae

    Paris, Kadri

    2003-01-01

    Riigivastutuse areng rahvusvahelises õiguses, riigivastutuse üldised põhimõtted, teo riigile omistamine õigusliku sideme olemasolul teo toimepanija ja riigi vahel, riigi vastutus eraisikute tegude eest

  10. Jungi salajane teos toodi seifist lagedale / Kaarel Kressa

    Index Scriptorium Estoniae

    Kressa, Kaarel, 1983-

    2009-01-01

    Carl Gustav Jungi Esimese maailmasõja järel kirjutatud teose "Liber Novus" käsikiri pannakse välja New Yorgi Rubini muuseumis. Samal päeval ilmub teos ka inglise ja saksa keeles raamatupoodidesse (kirjastaja W. W. Norton&Company)

  11. The optical properties of TeO2-Based Glasses

    International Nuclear Information System (INIS)

    Sahar, M.R.; Isahak, R.

    1994-01-01

    A series of binary glasses based on TeO2-PbCl2 has been prepared and their spectroscopy in the UV-Visible and IR regions has been investigated. It was found that the IR cut-off edge can go beyond 7μm and are largely influenced by the absorption due to Te-O-Te stretching vibrations around 638-644 cmsup -1 peaks

  12. The optical properties of TeO2-Based Glasses

    Energy Technology Data Exchange (ETDEWEB)

    Sahar, M R; Isahak, R [University Technology of Malaysia, Skudai Johor (Malaysia)

    1994-03-01

    A series of binary glasses based on TeO2-PbCl2 has been prepared and their spectroscopy in the UV-Visible and IR regions has been investigated. It was found that the IR cut-off edge can go beyond 7{mu}m and are largely influenced by the absorption due to Te-O-Te stretching vibrations around 638-644 cmsup -1 peaks.

  13. Structure of glasses of the TeO2-MoO3 system

    International Nuclear Information System (INIS)

    Dimitriev, Y.; Dimitrov, V.; Bart, J.C.J.

    1981-01-01

    Structural models for glasses of the TeO 2 -MoO 3 system are suggested. On the basis of X-ray and infrared spectral investigations, by comparing with known crystalline structures of TeO 2 , MoO 3 and Te 2 MoO 7 9t 2 M, it is shown that the glasses from TeO 2 to Te 2 MoO 7 possess [TeO 4 ] and [MoO 5 ] groups as basic structural units. The latter are connected to form [Mo 2 O 8 ] complexes. The glasses in the MoO 3 -rich compositional range are built up of [TeO 3 ] and [MoO 6 ] polyhedra. The glass-formation tendency is discussed in relation to the role of the free electron pair and the disruption of secondary and weak primary bonds in the crystals. (author)

  14. Võitlus kaevandustega tõi Enno Vinnile aasta rohelise teo tegija tiitli / Külli Kriis

    Index Scriptorium Estoniae

    Kriis, Külli, 1961-

    2006-01-01

    Vt. ka Severnoje Poberezhje 12. dets. Eesti keskkonnaühendused kuulutasid aasta positiivseima keskkonnateo tegijaks Maidla vallavolikogu esimehe Enno Vinni. Haridusminister Mailis Repsile omistati keskkonnavaenulikuma teo ehk karuteene tiitel

  15. Teadus- ja erialaraamatukogudel oma päev ja aasta teo auhind / Kristina Rallmann

    Index Scriptorium Estoniae

    Rallmann, Kristina

    2008-01-01

    Esimene teadus- ja erialaraamatukogude päev toimus 22. oktoobril 2008 Tallinna majanduskoolis, teadusraamatukogu aasta teo auhind läks RR-i virtuaaalnäitusele "Meie parlament ja aeg: fakte, sündmusi, dokumente, inimesi" ning erialaraamatukogu aasta teo auhind Eesti Pimedate Raamatukogu töörühmale heliteavikute CD-plaatidele automatiseeritud paljundamise ja posti teel laenutamise süsteemi eest

  16. Post-Irradiation Behaviour of I131 in TeO2

    International Nuclear Information System (INIS)

    Jaćimović, Lj.; Stevović, J.; Veljković, S.R.

    1965-01-01

    The system I 131 in TeO 2 is interesting because little is known about thermal chemical changes in this target. Radioiodine was produced by neutron irradiation of TeO 2 in the reactor. Irradiated TeO 2 was dissolved in diluted NaOH. The analysis of the iodine valency forms was made by ion exchange techniques. The thermal and radiation stability of TeO 2 was studied by using the spectrophotometric method for the determination of tellurium. Post-irradiation annealing of I 131 in TeO 2 was studied in dependence on the time and temperature of the heating. The main tendency of annealing was the reduction of radioiodine. The time dependence of this process indicates a fast change at high temperatures. The curves are more complex at lower temperatures. The annealing may appear complex because of the variety of thermal reactions of iodine intermediary. It may react with products of the following processes: tellurium recoil and corresponding hot zone, beta transition of Te 131 and TeO 2 itself. The kinetics of these changes was considered and an estimation of the processes during annealing was made. The influence of the neutron flux on the kinetics of annealing was also studied. (author) [fr

  17. Design and construction of a prototype to obtain TeO2

    International Nuclear Information System (INIS)

    Roque H, I.

    1997-01-01

    At the National Institute of Nuclear Research is developed the process to produce the radioisotope Iodine 131 which is employed in medicine with therapeutical purposes. The raw material to produce iodine 131 is tellurium dioxide (TeO 2 ). TeO 2 is intended to be produced from a prototype being this aim of this thesis named D esign and construction of a prototype to obtain TeO 2 . The TeO 2 obtained must have specific physicochemical characteristics, being necessary an special design of a prototype which will guarantee the quality of tellurium dioxide obtention. Design and building the final prototype project, was developed in to three stages. At the first stage, the TeO 2 was obtained at the laboratory, this allows to know the basic reaction characteristics. The second stage purpose, was to work with an former prototype which allowed to produce 100 g of tellurium dioxide. In the last stage a depurated chemical process parameters was made and the prototype was refined in regard to its mechanical design, giving us as result the final prototype. With this final prototype, the production reaches 2 Kg/week of tellurium dioxide with the best physicochemical properties which is to be employed as raw material in order to produce iodine 131. (Author)

  18. Fabrication of Nd:YAG transparent ceramics with both TEOS and MgO additives

    International Nuclear Information System (INIS)

    Yang Hao; Qin Xianpeng; Zhang Jian; Wang Shiwei; Ma Jan; Wang Lixi; Zhang Qitu

    2011-01-01

    Research highlights: → It is well known that the use of TEOS as sintering aid is required to reach fully dense and transparent Nd:YAG ceramics. However, it is difficult to produce high quality transparent Nd:YAG ceramics only using TEOS as sintering aid. In this present work, high quality transparent Nd:YAG ceramic was fabricated using both TEOS and MgO as sintering aids. There have been few reports that both TEOS and MgO were co-added as sintering aids in YAG or Nd:YAG transparent ceramics to date. The transmittance of Nd:YAG ceramic is 83.8% at 1064 nm. The effect of MgO on the optical properties of transparent ceramics was also studied. - Abstract: Neodymium doped YAG transparent ceramics were fabricated by vacuum reactive sintering method using commercial α-Al 2 O 3 , Y 2 O 3 and Nd 2 O 3 powders as the starting materials with both tetraethyl orthosilicate (TEOS) and MgO as sintering aids. The morphologies and microstructure of the powders and Nd:YAG transparent ceramics were investigated. Fully dense Nd:YAG ceramics with average grain size of ∼10 μm were obtained by vacuum sintering at 1780 deg. C for 8 h. No pores and grain-boundary phases were observed. The in-line transmittance of the ceramic was 83.8% at 1064 nm.

  19. Structure of TeO2 - LiNbO3 glasses

    Science.gov (United States)

    Shinde, A. B.; Krishna, P. S. R.; Rao, Rekha

    2017-05-01

    Tellurite based lithium niobate glasses with composition (100-x)TeO2-xLiNbO3 (x=0.1,0.2 & 0.3) were prepared by conventional melt quenching method. The microscopic structural investigation of these glasses is carried out by means of neutron diffraction and Raman scattering measurements. It is found that the basic structural units in these glasses are TeO4 trigonal bipyramids(TBP), TeO3 trigonal pyramids(TP) and NbO6 Octahedra depending on the composition. It is evident from Raman studies that TBPs decreases, TPs increases and NbO6 Octahedra increases with increasing x. From Neutron diffraction studies it is found that network is comprised of TBPs and TPs along with TeO3+1 structural units. Distorted NbO6 octahedral units are present and also increase with the increase in x.

  20. Background suppression in TeO2 bolometers with Neganov-Luke amplified cryogenic light detectors

    International Nuclear Information System (INIS)

    Willers, Michael

    2015-01-01

    Cryogenic detectors based on non-scintillating TeO 2 crystals are used in the search for the neutrinoless double beta decay, presently one of the most important fields of research in neutrino and astroparticle physics. Within this work, the application of Neganov-Luke amplified cryogenic light detectors for the background suppression in TeO 2 crystals is investigated. Alpha-induced background events can be discriminated from signal-like electron/gamma events via the detection of Cherenkov radiation produced by highly energetic electrons within the TeO 2 crystal. Using Neganov-Luke light detectors, it could be shown for the first time that a highly efficient event-by-event discrimination between alpha and electron/gamma-induced events can be achieved.

  1. Growth and Characterization of Magnetoelectric Fe2TeO6 Thin Films

    Science.gov (United States)

    Wang, Junlei; Colon Santana, Juan; Wu, Ning; Dowben, Peter; Binek, Christian

    2013-03-01

    Voltage-controlled spintronics is of vital importance in information technology where power consumption and Joule heating restrict progress through scaling. Motivated by spintronic concepts and specifically by device applications utilizing electrically controlled interface or boundary magnetization (BM) in magnetic thin film heterostructures, we report on growth, structural, magnetic and magnetoelectric (ME) characterization of the antiferromagnet Fe2TeO6. Magnetometry of synthesized Fe2TeO6 powder, in combination with ME susceptibility data reveals 3D Heisenberg criticality in striking similarity to the archetypical ME chromia. X-ray diffraction shows (110) texture of the PLD grown films. Measurements of the magnetic susceptibility of the latter confirm in-plane magnetic anisotropy. X-ray photoemission spectroscopy indicates a Te-O terminated (110) surface. We interpret it in terms of surface reconstruction. Measurements of X-ray magnetic circular dichroism combined with photoemission electron microscopy support the presence of electrically controllable BM in the PLD-grown Fe2TeO6 thin film. We acknowledge financial support by NSF-MRSEC & Nanoelectronics Research Initiative.

  2. Molecular dynamics investigation of Na+ in Na2Ni2TeO6

    International Nuclear Information System (INIS)

    Sau, Kartik; Kumar, P. Padma

    2014-01-01

    An inter-atomic potential for Na 2 Ni 2 TeO 6 in the Parrinello- Rahman-Vashishta (PRV) model is parameterized empirically. The potential reproduces variety of structural and transport properties of that material in good agreement with recent experimental results. The study provides fresh insights on the migration channels and mechanism of Na + in the system

  3. Hydrophobic and low density silica aerogels dried at ambient pressure using TEOS precursor

    International Nuclear Information System (INIS)

    Gurav, Jyoti L.; Rao, A. Venkateswara; Bangi, Uzma K.H.

    2009-01-01

    In the conventional ambient pressure drying of silica aerogels, tedious repetitive gel washing and solvent exchange steps (∼6 days) are involved. Therefore, in the present studies, we intended to reduce the processing time of TEOS based ambient pressure dried silica aerogels. Solvents such as methanol, hexane and Hexamethyldisilazane (HMDZ) as surface chemical modification agents have been used. To get good quality aerogels in terms of low density, high porosity, high contact angle and low volume shrinkage in less processing time, we varied MeOH/TEOS, HMDZ/TEOS molar ratios, oxalic acid (A) and NH 4 OH (B) concentrations and stirring time from 1 to 27.7, 0.34 to 2.1, 0 to 0.1 M, 0 to 2 M and 15 to 90 min respectively. The transparent and low-density aerogels were obtained for TEOS:MeOH:acidic H 2 O:basic H 2 O:HMDZ molar ratio of 1:16.5:0.81:0.50:0.681 respectively. The thermal stability and hydrophobicity have been confirmed with Thermogravimetric and Differential Thermal (TG-DT) analyses and Fourier Transform Infrared Spectroscopy. Microstructural study was carried out by Scanning Electron Microscopy (SEM)

  4. Raman spectra of TeO2-PbCl2 glasses

    Czech Academy of Sciences Publication Activity Database

    Ležal, Dimitrij; Bludská, Jana; Horák, J.; Sklenář, A.; Karamazov, S.; Vlček, M.

    2002-01-01

    Roč. 43, č. 6 (2002), s. 296-299 ISSN 0031-9090 Institutional research plan: CEZ:AV0Z4032918 Keywords : tellurite glasses * TeO2glass * model Subject RIV: CA - Inorganic Chemistry Impact factor: 0.691, year: 2002

  5. Accurate polynomial expressions for the density and specific volume of seawater using the TEOS-10 standard

    Science.gov (United States)

    Roquet, F.; Madec, G.; McDougall, Trevor J.; Barker, Paul M.

    2015-06-01

    A new set of approximations to the standard TEOS-10 equation of state are presented. These follow a polynomial form, making it computationally efficient for use in numerical ocean models. Two versions are provided, the first being a fit of density for Boussinesq ocean models, and the second fitting specific volume which is more suitable for compressible models. Both versions are given as the sum of a vertical reference profile (6th-order polynomial) and an anomaly (52-term polynomial, cubic in pressure), with relative errors of ∼0.1% on the thermal expansion coefficients. A 75-term polynomial expression is also presented for computing specific volume, with a better accuracy than the existing TEOS-10 48-term rational approximation, especially regarding the sound speed, and it is suggested that this expression represents a valuable approximation of the TEOS-10 equation of state for hydrographic data analysis. In the last section, practical aspects about the implementation of TEOS-10 in ocean models are discussed.

  6. Treffneri hoone pälvis Tartu aasta teo tiitli / Priit Rajalo

    Index Scriptorium Estoniae

    Rajalo, Priit, 1975-

    2002-01-01

    Viiendat korda välja antud Tartu aasta teo konkursi aunimetuse pälvis tänavu Huga Treffneri gümnaasiumi renoveeritud hoone, sümboliseerides vajadust anda rohkem raha haridusele. Tartu linnapea Andrus Ansipi sõnul kuulub see hoone praegu Euroopa kümne parima gümnaasiumihoone hulka

  7. Quantum mechanical study of pre-dissociation enhancement of linear and nonlinear polarizabilities of (TeO2)(n) oligomers as a key to understanding the remarkable dielectric properties of TeO2 glasses.

    Science.gov (United States)

    Smirnov, Mikhail; Mirgorodsky, Andrei; Masson, Olivier; Thomas, Philippe

    2012-09-20

    The effects of intermolecular interactions of TeO(2) molecules in the (TeO(2))(n) oligomers on the polarizability (α) and second hyperpolarizability (γ) are investigated by the use of a density functional method. A significant intermolecular distance dependence of both quantities is observed. The huge dissociation-induced polarizability enhancement is analyzed in terms of the molecular orbital evolution. It is shown that the obtained results can provide a new look at the microscopic origin of the extraordinary dielectric properties of TeO(2) glass.

  8. Infrared Spectroscopy and Raman Scattering Studies on the Structure of Ag2O. B2O3. TeO2 Glass

    International Nuclear Information System (INIS)

    Thazin Myint; Soe Soe Thin; Pho Kaung; Sein Htoon

    2006-06-01

    Infrared spectroscopy investigation of silver - borate - tellurite glasses in the system 0.4 Ag2 O. 0.6 (x B2 O2. (1-x) TeO2) for various of x (0 < x < 1) has been performed in order to understand the glass modifying properties of the TeO2. In pure crystalline TeO2 spectra observed absorption bands at 780 cm-1 and 660 cm-1 have been ascribed to the stretching vibration of TeO bonds in the TeO4 units. In the glass 0.4 Ag2 O. 0.6 (x B2 O3. (1-x) TeO2) the bands at 700 cm-1 and 694 cm-1 are assigned to the symmetric breathing vibration of the boroxol group and the pentaborate one. The glasses show bands at 630 cm-1 which corresponds to the vibrations due to TeO4 units

  9. Theoretical studies on a TeO2/ZnO/diamond-layered structure for zero TCD SAW devices

    International Nuclear Information System (INIS)

    Dewan, Namrata; Sreenivas, K; Gupta, Vinay

    2008-01-01

    High-frequency surface acoustic wave (SAW) devices based on diamond substrate are useful because of their very high SAW velocity. In the present work, SAW propagation characteristics, such as phase velocity, coupling coefficient and temperature coefficient of delay (TCD) of a TeO 2 /ZnO/diamond-layered structure, are examined using theoretical calculations. The ZnO/diamond bi-layer structure is found to exhibit a high positive TCD value. A zero TCD device structure is obtained after integration with a TeO 2 over layer having a negative TCD value. Introduction of a non-piezoelectric TeO 2 over layer on the bi-layer structure (ZnO/diamond) increases the coupling coefficient. A relatively low thickness of TeO 2 thin film (∼(1.6–3.1) × 10 −3 λ) is required to achieve temperature-stable SAW devices based on diamond

  10. Study of the optical properties of TeO2-PbO-TiO2 glass system

    Directory of Open Access Journals (Sweden)

    Raul F. Cuevas

    1998-06-01

    Full Text Available We describe the preparation and some optical properties of high refractive index TeO2-PbO-TiO2 glass system. Highly homogeneous glasses were obtained by agitating the mixture during the melting process in an alumina crucible. The characterization was done by X-ray diffraction, Raman scattering, light absorption and linear refractive index measurements. The results show a change in the glass structure as the PbO content increases: the TeO4 trigonal bipyramids characteristics of TeO2 glasses transform into TeO3 trigonal pyramids. However, the measured refractive indices are almost independent of the glass composition. We show that third-order nonlinear optical susceptibilities calculated from the measured refractive indices using Lines' theoretical model are also independent of the glass composition.

  11. Theoretical studies on a TeO2/ZnO/diamond-layered structure for zero TCD SAW devices

    Science.gov (United States)

    Dewan, Namrata; Sreenivas, K.; Gupta, Vinay

    2008-08-01

    High-frequency surface acoustic wave (SAW) devices based on diamond substrate are useful because of their very high SAW velocity. In the present work, SAW propagation characteristics, such as phase velocity, coupling coefficient and temperature coefficient of delay (TCD) of a TeO2/ZnO/diamond-layered structure, are examined using theoretical calculations. The ZnO/diamond bi-layer structure is found to exhibit a high positive TCD value. A zero TCD device structure is obtained after integration with a TeO2 over layer having a negative TCD value. Introduction of a non-piezoelectric TeO2 over layer on the bi-layer structure (ZnO/diamond) increases the coupling coefficient. A relatively low thickness of TeO2 thin film (~(1.6-3.1) × 10-3λ) is required to achieve temperature-stable SAW devices based on diamond.

  12. Upconversion in rare earth ions doped TeO2-ZnO glass

    International Nuclear Information System (INIS)

    Mohanty, Deepak Kumar; Rai, Vineet Kumar

    2012-01-01

    The Er 3+ /Yb 3+ doped/codoped TeO 2 -ZnO glasses have been fabricated by conventional melt and quenching technique. The absorption spectra of the doped/codoped glasses have been performed. The visible upconversion emissions of both doped and codoped glasses have been observed using 808 nm diode laser excitation. The process involved in upconversion emissions has been discussed in detail. (author)

  13. On the physical parametrization and magnetic analogs of the Emparan-Teo dihole solution

    International Nuclear Information System (INIS)

    Cazares, J.A.; Garcia-Compean, H.; Manko, V.S.

    2008-01-01

    The Emparan-Teo non-extremal black dihole solution is reparametrized using Komar quantities and the separation distance as arbitrary parameters. We show how the potential A 3 can be calculated for the magnetic analogs of this solution in the Einstein-Maxwell and Einstein-Maxwell-dilaton theories. We also demonstrate that, similar to the extreme case, the external magnetic field can remove the supporting strut in the non-extremal black dihole too

  14. 2.3 µm laser potential of TeO2 based glasses

    Science.gov (United States)

    Denker, B. I.; Dorofeev, V. V.; Galagan, B. I.; Motorin, S. E.; Sverchkov, S. E.

    2017-09-01

    Tm3+ doped TeO2-based well-dehydrated glasses were synthesized and investigated. The analysis of their spectral and relaxation properties have showed that these glasses can be a suitable host for bulk and fiber lasers emitting at ~2.3 µm wavelength (3H4-3H5 Tm3+ transition). Laser action in the bulk glass sample was demonstrated.

  15. Kinetic study and application of analytical techniques in the obtention of TeO2 for the production of 131 I

    International Nuclear Information System (INIS)

    Plata D, G.

    2006-01-01

    The objectives of this investigation work were: A) To synthesize TeO 2 starting from the reaction among the Te and HNO 3 with a superior yield to 90% b) To determine the good temperature of obtaining of the TeO 2 at laboratory level, c) To determine those constant of reaction kinetics, for each one of the tests carried out to different temperatures, and the activation energy of the reaction, d) To characterize the produced TeO 2 , e) To check the viability of using the obtained TeO 2 as raw matter in the production of 131 I in order to contribute to the technological development of our country inside the radioisotope production area. The production process of TeO 2 consists primarily of seven phases: 1) Preparing and assembly of the production equipment of TeO 2 , 2) Oxidation reaction of tellurium, 3) Drying and elimination of sludges of TeO 2 , 4) Sintering of TeO 2 , 5) Characterization of the TeO 2 by means of analytical techniques, 6) Irradiation of the TeO 2 , 7) Quality control. The present document has five chapters, which allow the reader to follow the development of this work to achieve the objectives and to contrast with the hypothesis of the work. (Author)

  16. Design and construction of the equipment and obtention process of TeO2 for the 131 I production

    International Nuclear Information System (INIS)

    Alanis M, J.

    2000-09-01

    This project was carried out in the National Institute of Nuclear Research, Nuclear Center of Mexico (ININ), with the name 'A New Method to Obtain 131 I by Neutron Irradiation of TeO 2 and it Dry Distillation'. This work establishes the optimal parameters to produce 131 I by neutron irradiation and foundry of TeO 2 sinterized. The TeO 2 of high purity was produced adding HNO 3 to the metallic tellurium (Merck 8100) and heating several samples to different temperatures until dryness in presence of an air current. The optimal conditions of temperature and reaction velocity were obtained, as well as of drying and sintering, to obtain TeO 2 crystals with high purity able to retain the 131 I produced by the radioactive decay. After drying and purified by the heating, the TeO 2 was sinterized, applying a next temperature to it melting point by few minutes, enough to create cavities in the middle of it crystalline structure, where the 131 I in gas form produced by the decay of the 131 Te it is retained, one time that the TeO 2 is bombarded with thermal neutrons in the nuclear reactor. Then, the reactions 130 Te(n, γ) 131 Te m (t 1/2 = 30 h) and 130 Te(n, γ) 131 Te (t 1/2 = 24.8 m) with an optimal irradiation time of 2.5 h. (Author)

  17. Hybrid NOTES: TEO for transanal total mesorectal excision: intracorporeal resection and anastomosis.

    Science.gov (United States)

    Serra-Aracil, Xavier; Mora-López, Laura; Casalots, Alex; Pericay, Carles; Guerrero, Raul; Navarro-Soto, Salvador

    2016-01-01

    Laparoscopic surgery for rectal TME achieves better patient recovery, lower morbidity, and shorter hospital stay than open surgery. However, in laparoscopic rectal surgery, the overall conversion rate is nearly 20%. Transanal TME combined with laparoscopy, known as Hybrid NOTES, is a less invasive procedure that provides adequate solutions to some of the limitations of rectal laparoscopy. Transanal TME via TEO with technical variants (intracorporeal resection and anastomosis, TEO review of the anastomosis) attempts to standardize and simplify the procedure. Prospective observational study was used describe and assess the technique in terms of conversion to open surgery, overall morbidity, surgical site infection and hospital stay. The sample comprised consecutive patients diagnosed with rectal tumor less than 10 cm from the anal verge who were candidates for low anterior resection using TME (except T4). Demographic, surgical, postoperative, and pathological variables were analyzed, as well as morbidity rates. From September 2012 to August 2014, 32 patients were included. The conversion rate was 0%. Overall morbidity was 31.3%, SSI rate was 9.4%, and mean hospital stay was 8 days. Oncological radical criteria were achieved with pathological parameters of 94% of complete TME and a median circumferential margin of 13 mm. The introduction of technical variants of TEO for transanal resection can facilitate a procedure that requires extensive experience in transanal and laparoscopic surgery. Studies of sphincter function, quality of life, and long-term oncological outcome are now necessary.

  18. Effect of TeO2 on the elastic moduli of sodium borate glasses

    International Nuclear Information System (INIS)

    Saddeek, Y.B.; Abd El Latif, Lamia

    2004-01-01

    Sodium borate glass containing tellurite as Te x Na 2-2x B 4-4x O 7-5x with x=0, 0.05, 0.15, 0.25 and 0.35 have been prepared by rapid quenching. Ultrasonic velocity (both longitudinal and shear) measurements have been made using a transducer operated at the fundamental frequency of 4 MHz at room temperature. The density was measured by the conventional Archimedes method. The elastic moduli, the Debye temperature, Poisson's ratio, and the parameters derived from the Makishima-Mackenzie model and the bond compression model have been obtained as a function of TeO 2 content. The monotonic decrease in the velocities and the elastic moduli, and the increase in the ring diameter and the ratio K bc /K e as a function of TeO 2 modifier content reveals the loose packing structure, which is attributed to the increase in the molar volume and the reduction in the vibrations of the borate lattice. The observed results confirm that the addition of TeO 2 changes the rigid character of Na 2 B 4 O 7 to a matrix of ionic behaviour bonds (NBOs). This is due to the creation of more and more discontinuities and defects in the glasses, thus breaking down the borax structure

  19. Low-temperature sintering and microwave dielectric properties of Al2TeO6–TeO2 ceramics

    International Nuclear Information System (INIS)

    Kagomiya, Isao; Kodama, Yuichiro; Shimizu, Yukihiro; Kakimoto, Ken-ichi; Ohsato, Hitoshi; Miyauchi, Yasuharu

    2015-01-01

    Highlights: • This is the first study of dielectric properties of Al 2 TeO 6 –TeO 2 sintered at 900 °C. • The sintering at 900 °C contributed to densification, but it causes TeO 2 evaporation. • The annealing at 750 °C was effective for the further densification. • The both ε r and Q · f in the Al 2 TeO 6 –TeO 2 were improved with the annealing. - Abstract: We propose Al 2 TeO 6 –TeO 2 ceramics as a candidate for use as low-temperature co-fired ceramics (LTCC). We investigated microwave dielectric properties and low-temperature sintering conditions for Al 2 TeO 6 –TeO 2 ceramics. The calcined Al 2 TeO 6 powders were sintered at 900 °C for 2–10 h with 30–50 wt% additive TeO 2 . X-ray powder diffraction patterns showed that the sintered samples were Al 2 TeO 6 –TeO 2 composite with no other phase. The apparent density was improved with the additive TeO 2 content of up to 45 wt%. The dielectric constant (ε r ) increased by adding TeO 2 content from 35 to 45 wt%, although the quality factor (Q · f) decreased. During sintering at 900 °C, the ε r of the Al 2 TeO 6 –TeO 2 decreased slightly, whereas the Q · f increased gradually. The observed microstructures showed that the longer sintering time makes fewer pores in Al 2 TeO 6 –TeO 2 ceramics. Sintering at 900 °C for a long time contributes to densification, but it simultaneously causes TeO 2 evaporation. To prevent TeO 2 evaporation, we investigated the effects of annealing at 750 °C after sintering at 900 °C. Apparent densities or ε r for the annealed samples were higher than those of the non-annealed samples. The Q · f improved with increasing annealing duration time, suggesting that sintering proceeded well during annealing with slower TeO 2 evaporation at 750 °C. The results show that annealing at 750 °C is effective to facilitate sintering and to control TeO 2 evaporation

  20. Thermodynamic characterization of Ni3TeO6, Ni2Te3O8 and NiTe2O5

    Science.gov (United States)

    Dawar, Rimpi; Babu, R.; Ananthasivan, K.; Anthonysamy, S.

    2017-09-01

    Measurement of vapour pressure of TeO2(g) over the biphasic mixture Ni3TeO6 (s) + NiO(s) in the temperature range 1143-1272 K was carried out using transpiration-thermogravimetric technique (TTG). Gibbs energy of formation of Ni3TeO6 was obtained from the temperature dependence of vapour pressure of TeO2 (g) generated by the incongruent vapourisation reaction, Ni3TeO6 (s) → NiO(s) + TeO2 (g) + 1/2 O2 in the temperature range 1143-1272 K. An isoperibol type drop calorimeter was used to measure the enthalpy increments of Ni3TeO6, Ni2Te3O8 and NiTe2O5. Thermodynamic functions viz., heat capacity, entropy and Gibbs energy functions of these compounds were derived from the experimentally measured enthalpy increment values. Third-law analysis was carried out to ascertain absence of temperature dependent systematic errors in the measurement of vapour pressure of TeO2 (g). A value of -1265.1 ± 1.5 kJ mol-1 was obtained for Δ Hf,298K o (Ni3TeO6) using third-law analysis.

  1. Equipment and obtention process of 131I by dry distillation starting from TeO2

    International Nuclear Information System (INIS)

    Alanis M, J.

    2000-08-01

    The present invention refers to an equipment and process for the obtaining of 131 I by dry distillation starting from TeO 2 that has three interconnected systems, the manipulation system, the electric system and the distillation system, the combination of these systems, allows to improve the yield and the separation of the 131 I during the distillation process, since inside the electric system it is an oven that has a special design based on a temperature gradient. The more relevant aspects of the equipment its are the design of each one of its components that give as result the effectiveness of the production of 131 I in routinary form (industrial) whose final product can end up reaching a radiochemical purity up to 99% and a radionuclide purity of approximately 100%. The object of this invention is to provide a distillation equipment different to those that at the moment exist, thanks to its novel internal construction whose main characteristics already gather advantages on those existent. The reaction of obtaining of the TeO 2 , the development of the technique and studies of TeO 2 sintering and the irradiation experiments, its contributed to characterize with more precision the 'new process of obtaining of 131 I by dry via starting from the Te' developed in the ININ, and in this way it was achieved a more pure product, more economic, with less risks, from a point of view of Radiological Safety and mainly that it avoids the import to the country and it makes to self-sufficient Mexico in the production of 131 I. (Author)

  2. Improvements in 130Te double beta decay search with cryogenic TeO2 array detectors

    International Nuclear Information System (INIS)

    Alessandrello, A.; Brofferio, C.; Bucci, C.; Caspani, P.; Cremonesi, O.; Fiorini, E.; Giuliani, A.; Nucciotti, A.; Pavan, M.; Pessina, G.; Previtali, E.; Zanotti, L.

    1996-01-01

    Single crystal TeO 2 bolometers have been used since 5 years ago to search for neutrinoless DBD of 130 Te. During the last year, our group has been studying and preparing the first array of 4 crystals, 340 g each, opening this technique to new frontiers in rare events' physics. The results and perspectives of this second generation cryogenic detectors are here reported and discussed, with particular emphasis on the peculiarities which make them feasible for a consistent upgrading of our previous result in DBD search. (orig.)

  3. Structural and thermal properties of tellurite 20Li2O-80TeO2 glasses

    OpenAIRE

    Idalgo, E. [UNESP; Araújo, E. B. [UNESP

    2007-01-01

    O presente trabalho reporta estudos sobre a cristalização em vidros teluretos 20Li2O-80TeO2 induzida a partir de tratamentos térmicos realizados sobre vidros com tamanho de partículas entre 38 µm e 75 µm. Estes estudos foram conduzidos em duas matrizes vítreas tratadas e não tratadas termicamente para aliviar as tensões após o quenching, utilizando-se de forma combinada às técnicas de difração de raios X, calorimetria diferencial de varredura e espectroscopia no infravermelho. Os resultados r...

  4. Interlocked chiral/polar domain walls and large optical rotation in Ni3TeO6

    Directory of Open Access Journals (Sweden)

    Xueyun Wang

    2015-07-01

    Full Text Available Chirality, i.e., handedness, pervades much of modern science from elementary particles, DNA-based biology to molecular chemistry; however, most of the chirality-relevant materials have been based on complex molecules. Here, we report inorganic single-crystalline Ni3TeO6, forming in a corundum-related R3 structure with both chirality and polarity. These chiral Ni3TeO6 single crystals exhibit a large optical specific rotation (α—1355° dm−1 cm3 g−1. We demonstrate, for the first time, that in Ni3TeO6, chiral and polar domains form an intriguing domain pattern, resembling a radiation warning sign, which stems from interlocked chiral and polar domain walls through lowering of the wall energy.

  5. Development of composite membranes of PVA-TEOS doped KOH for alkaline membrane fuel cell

    International Nuclear Information System (INIS)

    Haryadi,; Sugianto, D.; Ristopan, E.

    2015-01-01

    Anion exchange membranes (AEMs) play an important role in separating fuel and oxygen (or air) in the Alkaline Membrane Fuel Cells. Preparation of hybrid organic inorganic materials of Polyvinylalcohol (PVA) - Tetraethylorthosilicate (TEOS) composite membrane doped KOH for direct alcohol alkaline fuel cell application has been investigated. The sol-gel method has been used to prepare the composite membrane of PVA-TEOS through crosslinking step and catalyzed by concentrated of hydrochloric acid. The gel solution was cast on the membrane plastic plate to obtain membrane sheets. The dry membranes were then doped by immersing in various concentrations of KOH solutions for about 4 hours. Investigations of the cross-linking process and the presence of hydroxyl group were conducted by FTIR as shown for frequency at about 1600 cm −1 and 3300 cm −1 respectively. The degree of swelling in ethanol decreased as the KOH concentration for membrane soaking process increased. The ion exchange capacity (IEC) of the membrane was 0.25meq/g. This composite membranes display significant ionic conductivity of 3.23 x 10 −2 S/cm in deionized water at room temperature. In addition, the morphology observation by scanning electron microscope (SEM) of the membrane indicates that soaking process of membrane in KOH increased thermal resistant

  6. Development of composite membranes of PVA-TEOS doped KOH for alkaline membrane fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Haryadi,, E-mail: haryadi@polban.ac.id; Sugianto, D.; Ristopan, E. [Department of Chemical Engineering, Politeknik Negeri Bandung Jl. Gegerkalong Hilir, Ds. Ciwaruga, Bandung West Java (Indonesia)

    2015-12-29

    Anion exchange membranes (AEMs) play an important role in separating fuel and oxygen (or air) in the Alkaline Membrane Fuel Cells. Preparation of hybrid organic inorganic materials of Polyvinylalcohol (PVA) - Tetraethylorthosilicate (TEOS) composite membrane doped KOH for direct alcohol alkaline fuel cell application has been investigated. The sol-gel method has been used to prepare the composite membrane of PVA-TEOS through crosslinking step and catalyzed by concentrated of hydrochloric acid. The gel solution was cast on the membrane plastic plate to obtain membrane sheets. The dry membranes were then doped by immersing in various concentrations of KOH solutions for about 4 hours. Investigations of the cross-linking process and the presence of hydroxyl group were conducted by FTIR as shown for frequency at about 1600 cm{sup −1} and 3300 cm{sup −1} respectively. The degree of swelling in ethanol decreased as the KOH concentration for membrane soaking process increased. The ion exchange capacity (IEC) of the membrane was 0.25meq/g. This composite membranes display significant ionic conductivity of 3.23 x 10{sup −2} S/cm in deionized water at room temperature. In addition, the morphology observation by scanning electron microscope (SEM) of the membrane indicates that soaking process of membrane in KOH increased thermal resistant.

  7. Development of composite membranes of PVA-TEOS doped KOH for alkaline membrane fuel cell

    Science.gov (United States)

    Haryadi, Sugianto, D.; Ristopan, E.

    2015-12-01

    Anion exchange membranes (AEMs) play an important role in separating fuel and oxygen (or air) in the Alkaline Membrane Fuel Cells. Preparation of hybrid organic inorganic materials of Polyvinylalcohol (PVA) - Tetraethylorthosilicate (TEOS) composite membrane doped KOH for direct alcohol alkaline fuel cell application has been investigated. The sol-gel method has been used to prepare the composite membrane of PVA-TEOS through crosslinking step and catalyzed by concentrated of hydrochloric acid. The gel solution was cast on the membrane plastic plate to obtain membrane sheets. The dry membranes were then doped by immersing in various concentrations of KOH solutions for about 4 hours. Investigations of the cross-linking process and the presence of hydroxyl group were conducted by FTIR as shown for frequency at about 1600 cm-1 and 3300 cm-1 respectively. The degree of swelling in ethanol decreased as the KOH concentration for membrane soaking process increased. The ion exchange capacity (IEC) of the membrane was 0.25meq/g. This composite membranes display significant ionic conductivity of 3.23 x 10-2 S/cm in deionized water at room temperature. In addition, the morphology observation by scanning electron microscope (SEM) of the membrane indicates that soaking process of membrane in KOH increased thermal resistant.

  8. Large optical second-order nonlinearity of poled WO3-TeO2 glass.

    Science.gov (United States)

    Tanaka, K; Narazaki, A; Hirao, K

    2000-02-15

    Second-harmonic generation, one of the second-order nonlinear optical properties of thermally and electrically poled WO>(3)-TeO>(2) glasses, has been examined. We poled glass samples with two thicknesses (0.60 and 0.86 mm) at various temperatures to explore the effects of external electric field strength and poling temperature on second-order nonlinearity. The dependence of second-harmonic intensity on the poling temperature is maximum at a specific poling temperature. A second-order nonlinear susceptibility of 2.1 pm/V was attained for the 0.60-mm-thick glass poled at 250 degrees C. This value is fairly large compared with those for poled silica and tellurite glasses reported thus far. We speculate that the large third-order nonlinear susceptibility of WO>(3)- TeO>(2) glasses gives rise to the large second-order nonlinearity by means of a X((2)) = 3X((3)) E(dc) process.

  9. Particle Sampling and Real Time Size Distribution Measurement in H2/O2/TEOS Diffusion Flame

    International Nuclear Information System (INIS)

    Ahn, K.H.; Jung, C.H.; Choi, M.; Lee, J.S.

    2001-01-01

    Growth characteristics of silica particles have been studied experimentally using in situ particle sampling technique from H 2 /O 2 /Tetraethylorthosilicate (TEOS) diffusion flame with carefully devised sampling probe. The particle morphology and the size comparisons are made between the particles sampled by the local thermophoretic method from the inside of the flame and by the electrostatic collector sampling method after the dilution sampling probe. The Transmission Electron Microscope (TEM) image processed data of these two sampling techniques are compared with Scanning Mobility Particle Sizer (SMPS) measurement. TEM image analysis of two sampling methods showed a good agreement with SMPS measurement. The effects of flame conditions and TEOS flow rates on silica particle size distributions are also investigated using the new particle dilution sampling probe. It is found that the particle size distribution characteristics and morphology are mostly governed by the coagulation process and sintering process in the flame. As the flame temperature increases, the effect of coalescence or sintering becomes an important particle growth mechanism which reduces the coagulation process. However, if the flame temperature is not high enough to sinter the aggregated particles then the coagulation process is a dominant particle growth mechanism. In a certain flame condition a secondary particle formation is observed which results in a bimodal particle size distribution

  10. Flebotomíneos de Timóteo, Estado de Minas Gerais, Brasil (Diptera: Psychodidae Sand flies in Timóteo, Minas Gerais, Brazil (Diptera: Psychodidae

    Directory of Open Access Journals (Sweden)

    José Dilermando Andrade Filho

    1997-10-01

    Full Text Available Casos esporádicos de leishmaniose tegumentar têm ocorrido no Município de Timóteo, Minas Gerais, basicamente na população rural. Para conhecer a fauna de flebotomíneos da região, foram instaladas sete armadilhas luminosas de New Jersey na cidade, em sete diferentes bairros. As coletas foram realizadas no período de junho a outubro de 1994, dezembro de 1994 e janeiro a março de 1995, com um total de 3.240 horas por armadilha. Foram capturados 4.396 flebotomíneos, distribuídos em dois gêneros e vinte espécies: Brumptomyia cunhai, Brumptomyia nitzulescui, Lutzomyia (Nyssomyia whitmani, Lutzomyia (Nyssomyia intermedia, Lutzomyia quinquefer, Lutzomyia lenti, Lutzomyia (Pintomyia fischeri, Lutzomyia migonei, Lutzomyia sallesi, Lutzomyia termitophila, Lutzomyia aragaoi, Lutzomyia borgmeieri, Lutzomyia (Psathyromyia lutziana, Lutzomyia (Sciopemyia sordellii, Lutzomyia (Pintomyia pessoai, Lutzomyia (Trichopygomyia longispina, Lutzomyia misionensis, Lutzomyia (Psychodopygus davisi, Lutzomyia lanei, Lutzomyia (Pressatia sp. A espécie L. (N. whitmani foi a mais freqüente com 52,12%, seguida de L. (N. intermedia com 34,10%, e ambas podem estar participando da transmissão de leishmaniose cutânea na região.Sporadic cases of tegumentary leishmaniasis have occurred in Timóteo, Minas Gerais State, basically among the rural population. In order to study the region's sand fly population, New Jersey light traps were set in seven different neighborhoods. Specimens were gathered from June through October 1994, December 1994, and January through March 1995, with a total of 3,240 hours per trap. A total of 4,396 sand flies were captured, distributed among two genera and twenty species: Brumptomyia cunhai, Brumptomyia nitzulescui, Lutzomyia (Nyssomyia whitmani, Lutzomyia (Nyssomyia intermedia, Lutzomyia quinquefer, Lutzomyia lenti, Lutzomyia (Pintomyia fischeri, Lutzomyia migonei, Lutzomyia sallesi, Lutzomyia termitophila, Lutzomyia aragaoi, Lutzomyia

  11. Structural studies of WO3-TeO2 glasses by high-Q-neutron diffraction and Raman spectroscopy

    International Nuclear Information System (INIS)

    Khanna, A.; Kaur, A.; Krishna, P.S.R.; Shinde, A.B.

    2013-01-01

    Glasses from the system: xWO 3 -(100-x)TeO 2 (x=15, 20 and 25 mol %) were prepared by melt quenching technique and characterized by density, UV-visible absorption spectroscopy, Differential Scanning Calorimetry (DSC), Raman spectroscopy and high-Q neutron diffraction measurements. Glass density and glass transition temperature increased with increase in WO 3 concentration, Raman spectroscopy indicated the conversion of TeO 4 units into TeO 3 units with increase in WO 3 content. The increase in glass transition temperature with the incorporation of WO 3 was attributed to the increase in average bond strength of the glass network since the bond dissociation energy of W-O bonds (672 kJ/mol) is significantly higher than that of Te-O bonds (376 kJ/mol). UV-visible studies found a very strong optical absorption band due to W 6+ ions, just below the absorption edge. High-Q neutron diffraction measurements were performed on glasses and radial distribution function analyses revealed changes in W-O and Te-O correlations in the glass network. The findings about changes in glass structure from neutron diffraction studies were consistent with structural information obtained from Raman spectroscopy and structure-property correlations were made. (author)

  12. Dielectric properties of the ternary TeO2/Nb2O5/ZnO glasses

    International Nuclear Information System (INIS)

    Ahmad, Mohamad M.; Yousef, El Sayed; Moustafa, El Sayed

    2006-01-01

    Glasses of the system TeO 2 /Nb 2 O 5 /ZnO containing different concentration of ZnO (ranging from 5 to 20 mol%) were prepared. The dielectric properties over wide ranges of frequencies and temperatures were investigated as a function of ZnO content by impedance spectroscopy measurements. The impedance spectra of the present glasses were modeled by appropriate equivalent circuit. The dielectric constant has a value of 66 for the 85TeO 2 /10Nb 2 O 5 /5ZnO glass, which is three times larger than that of pure TeO 2 glass and other binary, e.g. TeO 2 /ZnCl 2 , tellurite glassy systems. The results have been analyzed in light of varying NbO 6 octahedra and NbO 4 tetrahedra of niobium oxide as zinc oxide varies from 5 to 20 mol%. The relaxation properties of the investigated glasses are presented in the electric modulus formalism, where the relaxation time and the respective activation energy are determined

  13. Evaluation of TeO2 content on the optical and spectroscopic properties of Yb3 +-doped calcium borotellurite glasses

    Science.gov (United States)

    Lima, A. M. O.; Gomes, J. F.; Hegeto, F. L.; Medina, A. N.; Steimacher, A.; Barboza, M. J.

    2018-03-01

    This paper reports the synthesis and the characterization of Yb3 +-doped calcium borotellurite (CaBTeX) glasses with composition 10CaF2-(29.5 - 0.4x)CaO-(60 - 0.6x)B2O3-xTeO2-0.5Yb2O3 (x = 10, 16, 22, 31 and 54 mol%). The results of XRD confirm the amorphous character of all the samples. The density, molar volume, refractive index and electronic polarizability values show an increase with TeO2 content. Otherwise, the optical band gap energy shows a decrease with the increase of TeO2 content. The replacement of CaO and B2O3 by TeO2 changes the glass structure, which decreases the excited Yb3 +/cm3 and, consequently, the luminescence intensity. The temperature dependence of luminescence was studied for all the samples up to 420 K. The fluorescence lifetime does not change significantly due to TeO2 addition. In addition, absorption and emission cross section were calculated and present high values as compared to other tellurite and phosphate glasses.

  14. Study of the tellurite-rich composition range in the Bi2O3-TeO2 system

    International Nuclear Information System (INIS)

    Ghazaryan, A.A.

    2015-01-01

    The TeO 2 and Bi 2 O 3 based glasses and glass ceramics are widely used for various technical needs. However, information about the phase diagram of the Bi 2 O 3 -TeO 2 system is limited, and the existing data are inconsistent. According to Demina L.A. with co-authors the Bi 2 Te 4 O 1 1 compound has a congruent melting at 662°C and forms two eutectics with neighbors. In another case, according to the Schmidt P. with co-authors, it melts incongruently at 645°C without indication of Liquidus temperature. It was the motivation for the Bi 2 Te 4 O 1 1 melting behavior investigation and the binary Bi 2 O 3 -TeO 2 system phase diagram correction in the TeO 2 rich area of compositions. As initial materials the glass and solid state sintered samples were used for these purposes. The differential thermal and X-ray analyses were used for glassy and crystallized products identification. The exothermic effect with maximum at 420°C and two endothermal effects with minimum at 635°C and 720 Degree C are clearly observed on the DTA curve of the 80 TeO 2 -20 Bi 2 O 3 (mol.percent) glass composition corresponding to the Bi 2 Te 4 O 1 1 compound. The product of Bi 2 Te 4 O 1 1 glass powder crystallization at 420°C is the Bi 2 Te 4 O 1 1 compound with melting point of 635 ± 5°C. The second endothermic effect on the DTA curve in the range of temperature 680-765°C with minimum at 720°C, is associated with dissolution of TeO 2 in the melt, formed as result of the Bi 2 Te 4 O 1 1 incongruent melting. The existence of eutectic E 1 (87 mol.percent TeO 2 ) between Bi 2 Te 4 O 1 1 and TeO 2 with a melting point of 580 ±5°C has been confirmed. Incongruent melting promotes the peritectic P 1 (81 mol.percent TeO 2 ) formation between Bi 2 Te 4 O 1 1 and eutectic E 1 (87 mol.percent TeO 2 ) with a melting point of 635±5°C. Three endothermic effects at 560 °C, 635 °C and 720°C have been observed on the DTA curve of Bi 2 Te 4 O 1 1 compound, obtained by solid state synthesis. Last

  15. Lattice anomalies and magnetic excitations of the spin web compound Cu3TeO6

    International Nuclear Information System (INIS)

    Choi, K Y; Lemmens, P; Choi, E S; Berger, H

    2008-01-01

    We report on the magnetic susceptibility and Raman scattering measurements of the S = 1/2 three-dimensional (3D) spin web compound Cu 3 TeO 6 . The magnetic susceptibility shows an antiferromagnetic ordering at T N ∼61 K and a deviation from the Curie-Weiss law around 150 K. Raman spectra show the emergence of a new mode at 132 cm -1 for temperatures below T*∼50 K (∼0.8 T N ). At the same temperature, phonon anomalies in intensity and frequency show up. This gives evidence of pronounced magneto-elastic effects. In addition, we observe a two-magnon Raman spectrum around 214 cm -1 . Compared to typical 3D spin systems, its robust temperature dependence suggests that a frustrated spin topology with a reduced spin coordination number also enhances spin-phonon couplings.

  16. A Quantitative Method for Localizing User Interface Problems: The D-TEO Method

    Directory of Open Access Journals (Sweden)

    Juha Lamminen

    2009-01-01

    Full Text Available A large array of evaluation methods have been proposed to identify Website usability problems. In log-based evaluation, information about the performance of users is collected and stored into log files, and used to find problems and deficiencies in Web page designs. Most methods require the programming and modeling of large task models, which are cumbersome processes for evaluators. Also, because much statistical data is collected onto log files, recognizing which Web pages require deeper usability analysis is difficult. This paper suggests a novel quantitative method, called the D-TEO, for locating problematic Web pages. This semiautomated method explores the decomposition of interaction tasks of directed information search into elementary operations, deploying two quantitative usability criteria, search success and search time, to reveal how a user navigates within a web of hypertext.

  17. Structure and properties of TeO2-WO3 system glasses

    International Nuclear Information System (INIS)

    Kolobkov, V.P.; Ovcharenko, N.V.; Morozova, I.N.; Chebotarev, S.A.; Chikovskij, A.N.; Arkatova, T.G.

    1987-01-01

    Study of TeO 2 -WO 3 system is of interest for production of high-refractive-glasses with comparatively low crystallizability. Results of investigating some properties and structural features of this system glasses are presented. Composition and properties of studied glasses are presented. The properties were studied using the following techniques: the density was measured by hydrostatic weighing in toluene; thermal expansion coefficient was measured in quartz dilatometer DKV-5A; dilatometric temperature of glass softening (T g ) was defined as an intersection point of linear and curved parts of the plot of thermal expansion coefficient; refractive index (RI) - by immersion method; dielectric properties are measured. Consideration of vibronic spectra permits to conclude that in tungsten-tellurium glasses rare earth activator ions are arranged near tellurite and tungstate groupings proportional to glass-forming component content

  18. The electronic spectra of FeH and TeO2

    International Nuclear Information System (INIS)

    Hullah, D.F.

    1999-01-01

    A thesis submitted for the degree of Doctor of Philosophy at the University of Oxford. Daniel Fearnley Hullah, Jesus College, Trinity Term 1999. This thesis is presented in two parts. The subject of Part One is the recording and analysis of part of the electronic spectrum of the iron monohydride, FeH, at visible wavelengths with Doppler-limited resolution. The subject of Part Two is the recording and analysis of the electronic spectrum of tellurium dioxide, TeO 2 , at near ultra-violet wavelengths under free jet expansion conditions. PART ONE: The fourth sub-bands of the e 6 Π-c 6 Σ + and e 6 Π-a 6 Δ transitions of FeH were recorded using both direct laser induced fluorescence and dispersed laser induced fluorescence. A total of sixteen lines were assigned to the e 6 Π 1/2 -c 6 Σ + -1/2 transition and fourteen lines were assigned to the e 6 Π 1/2 -a 6 Δ 3/2 transition. This allowed the e 6 Π 1/2 spin-orbit component to be characterised for J levels from 1/2 to 7/2 and the a 6 Δ 3/2 spin-orbit component to be characterised for J levels from 3/2 to 9/2. The first sub-band of the e 6 Π-a 6 Δ transition was extended following analysis of the high temperature spectrum of McCormack and O'Connor (recorded in 1976). Dispersed fluorescence spectra of the first four sub-bands of the e 6 Π-a 6 Δ transition were recorded. Following analysis, transitions at ∼ 600 nm were recorded using direct laser induced fluorescence. These were assigned to transitions from the first three spin-orbit components of a new sextet electronic state, b 6 Π (e 6 Π-b 6 Π), one spin orbit component of a new quartet state, C 4 Φ 7/2 , (e 6 Π 5/2 -C 4 Φ 7/2 ), and the previously observed X 4 Δ 7/2 υ = 2 state (e 6 Π 7/2 -X 4 Δ 7/2 υ = 2). PART TWO: The electronic spectrum of TeO 2 was recorded between 345 and 406 nm using a pulsed dye laser. TeO 2 (g) was produced by heating TeO 2(s) to 850 deg. C and entraining the vapour in argon and expanding the gases in a continuous free

  19. The hydrophobic and omnidirectional antireflection coating of SiO2 nanospheres with C18-TEOS

    Science.gov (United States)

    Hsu, Cheng-Chih; Lan, Wen-Lin; Chen, Nien-Po; Wu, Chyan-Chyi

    2014-06-01

    This paper demonstrates the antireflection coating of SiO2 nanospheres applied to cover glass by using the optimal spin-coating method. Because of the hydrolysis and condensation reactions between the SiO2 nanosphere antireflection (AR) coating and n-octadecyltriethoxysilane solution (C18-TEOS), the contact angle of the AR coating with hydrophobic treatment is improved approximately 38%, and the moisture-resistance remains unchanged, which preserved similar transmittance for six weeks. Furthermore, the AR coating with hydrophobic treatment exhibits approximately 3% and 7% improvement in the transmittance at normal and oblique incidence, respectively. The hydrophobic and omnidirectional AR coating with nanoscale SiO2 particles can be fabricated using the proposed simple and economical method.

  20. Photovoltaic effect in Bi2TeO5 photorefractive crystal

    International Nuclear Information System (INIS)

    Oliveira, Ivan de; Capovilla, Danilo Augusto; Carvalho, Jesiel F.; Montenegro, Renata; Fabris, Zanine V.; Frejlich, Jaime

    2015-01-01

    We report on the presence of a strong photovoltaic effect on nominally undoped photorefractive Bi 2 TeO 5 crystals and estimated their Glass photovoltaic constant and photovoltaic field for λ = 532 nm illumination. We directly measured the photovoltaic-based photocurrent in this material under λ = 532 nm wavelength laser light illumination and compared its behavior with that of a well known photovoltaic Fe-doped Lithium Niobate crystal. We also show the photovoltaic current to strongly depend on the polarization direction of light. Holographic diffraction efficiency oscillation during recording and the behavior of fringe-locked running holograms in self-stabilized experiments are also demonstrated here as additional indirect proofs of the photovoltaic nature of this material

  1. Electric behavior of functional glasses based on TeO2

    International Nuclear Information System (INIS)

    Terny, S.; Rubia, M. a. de la; Barolin, S.; Alonso, R. E.; Frutos, J. de; Frechero, M. A.

    2014-01-01

    In this paper we study the structural and electrical behavior of glass-ceramic material of general formula: xMgO (1-x) (0.5V 2 O 5 .0.5MoO 3 )2TeO 2 (0≤ x≤0.9) through measurements of density, molar volume, oxygen packing density (OPD), differential scanning calorimetry (DSC) and Raman spectroscopy: electric behavior was studied by impedance spectroscopy. We found that magnesium cation induces the growth of slightly crystallized areas inside the material. Those nanocrystallizations were detected to a greater extent by atomic force microscopy (AFM) and in lesser extent by X-ray diffraction (XRD). Regarding the electrical measurements, it can be established that magnesium cation does not act as good ionic conductor in this material. (Author)

  2. Sand flies in Timóteo, Minas Gerais, Brazil (Diptera: Psychodidae)

    OpenAIRE

    Andrade Filho, José Dilermando; Carneiro, Ana Paula Salgado; Lima, Mauro Lucio Nascimento; Santiago, Rodrigo Martins; Gama, Marco Antônio; Santos, Carlos Alberto; Falcão, Alda Lima; Brazil, Reginaldo Peçanha

    1997-01-01

    Casos esporádicos de leishmaniose tegumentar têm ocorrido no Município de Timóteo, Minas Gerais, basicamente na população rural. Para conhecer a fauna de flebotomíneos da região, foram instaladas sete armadilhas luminosas de New Jersey na cidade, em sete diferentes bairros. As coletas foram realizadas no período de junho a outubro de 1994, dezembro de 1994 e janeiro a março de 1995, com um total de 3.240 horas por armadilha. Foram capturados 4.396 flebotomíneos, distribuídos em dois gêneros e...

  3. Obtention, sintering and operational tests of the obtention prototype TeO2 for the production of 131 I

    International Nuclear Information System (INIS)

    Alanis M, J.

    1997-12-01

    The demand that exists in Mexico of developing production techniques of applicable radiopharmaceuticals in nuclear medicine, it forces to the National Institute of Nuclear Research to develop the obtaining process of 131 I by dry via starting from TeO 2 . The obtaining process of 131 I, it begins with the synthesis of the TeO 2 like matter prevails, starting from the oxidation of Te-elementary one, inside HNO 3 . Later on the TeO 2 , passes to the sintering process in ingots form, in that way it is encapsulated in aluminum, to be irradiated under optimal parameters of irradiation in the nuclear reactor. The irradiated TeO 2 , it passes to the stage of distillation of 131 I, in a distillation equipment of 131 I by dry via starting from TeO 2 . The process equipment consists mainly of three parts: a) the system of distillation control, built of steel, aluminum, bronze and brass, among other, b) distillation system, built of glass pyrex and of quartz, in this system is where the chemical and nuclear reactions take place for the obtaining of 131 I and c) electric system, is the one in charge of the electric energy supply for the process oven, ventilation system and vacuum system. The results of experimental tests, check the effectiveness of the production process of 131 I in the ININ in routine form (industrial), however it is indispensable to optimize the physical, chemical and nuclear parameters that intervene in each stage of the process with the purpose to obtaining the maximum yield, purity, quality and radiological control and economic production costs. (Author)

  4. Comportamiento eléctrico de vidrios funcionales con base en TeO2

    Directory of Open Access Journals (Sweden)

    Terny, S.

    2014-02-01

    Full Text Available In this paper we study the structural and electrical behavior of glass-ceramic material of general formula: xMgO (1-x (0.5V2O5.0.5MoO32TeO2 (0≤x≤0.9 through measurements of density, molar volume, oxygen packing density (OPD, differential scanning calorimetry (DSC and Raman spectroscopy: electric behavior was studied by impedance spectroscopy. We found that magnesium cation induces the growth of slightly crystallized areas inside the material. Those nanocrystallizations were detected to a greater extent by atomic force microscopy (AFM and in lesser extent by X-ray diffraction (XRD. Regarding the electrical measurements, it can be established that magnesium cation does not act as good ionic conductor in this material.En este trabajo estudiamos la estructura de un material vítreo cuya fórmula general es: xMgO(1-x(0.5V2O5.0.5MoO32TeO2 (0≤x≤0.9, mediante medidas de densidad, volumen molar, empaquetamiento denso de oxigeno (OPD, calorimetría diferencial de barrido (DSC y espectroscopia Raman; el comportamiento eléctrico se estudió por medio de espectroscopia de impedancia. Encontramos que el catión magnesio induce el crecimiento de zonas levemente cristalizadas dentro del material. Dichas nanocristalizaciones pudieron ser detectadas en mayor medida por microscopia de fuerzas atómicas (AFM y en menor medida se pudo observar en los patrones de difracción de Rayos X (DRX. Con respecto a las propiedades eléctricas, se puede establecer que el catión magnesio no actúa como buen conductor iónico en este material.

  5. Cd3(MoO4)(TeO3)2: A Polar 3D Compound Containing d10-d0 SCALP-Effect Cations.

    Science.gov (United States)

    Feng, Yuquan; Fan, Huitao; Zhong, Zhiguo; Wang, Hongwei; Qiu, Dongfang

    2016-11-21

    The new polar 3D cadmium molybdotellurite Cd 3 (MoO 4 )(TeO 3 ) 2 was obtained by means of a high-temperature solid-state method. Cd 3 (MoO 4 )(TeO 3 ) 2 is a monoclinic crystal system, and it exhibits the polar space group P2 1 (No. 4). The structure of Cd 3 (MoO 4 )(TeO 3 ) 2 can be viewed as a complicated 3D architecture that is composed of distorted CdO n (n = 6, 7) polyhedra, TeO 3 trigonal pyramids, and MoO 4 polyhedra. The compound features the first 3D NCS cadmium molybdotellurite with 1D 4- and 6-MR channels and a polar structure originating from the TeO 3 groups, MoO 4 groups, and displacements of d 10 Cd 2+ cations. The results were further confirmed by calculations of the net polarization. The UV-vis spectrum and thermal properties indicate that Cd 3 (MoO 4 )(TeO 3 ) 2 exhibits a broad transparent region and excellent thermal stability. SHG tests of Cd 3 (MoO 4 )(TeO 3 ) 2 revealed that its response is approximately the same as that of KH 2 PO 4 at the same grain size between 105 and 150 μm and that it is phase-matchable.

  6. Electrical mobility of silver ion in Ag2O-B2O3-P2O5-TeO2 glasses.

    Science.gov (United States)

    Sklepić, Kristina; Vorokhta, Maryna; Mošner, Petr; Koudelka, Ladislav; Moguš-Milanković, Andrea

    2014-10-16

    The effect of adding TeO(2) into (100 - x)[0.5Ag(2)O - 0.1B(2)O(3) - 0.4P(2)O(5)] - xTeO(2), with 0-80 mol % TeO(2) glass, on the structural changes and electrical properties has been investigated. DSC and thermodilatomery were used to study their thermal behavior, structure was studied by Raman spectroscopy, and electrical properties have been studied by impedance spectroscopy over a wide temperature and frequency range. The introduction of TeO(2) as a third glass former to the glass network causes the structural transformation from TeO(3) (tp) to TeO(4) (tbp) which contributes to the changes in conductivity. The glasses with low TeO(2) content show only a slow decrease in dc conductivity with addition of TeO(2) due to the increase of the number of nonbridging oxygens, which increases the mobility of Ag(+) ions. The steep decrease in conductivity for glasses containing more than 40 mol % TeO(2) is a result of decrease of the Ag(2)O content and stronger cross-linkage in glass network through the formation of more Te-(eq)O(ax)-Te bonds in TeO(4) tbp units. The glasses obey ac conductivity scaling with respect to temperature, implying that the dynamic process is not temperature dependent. On the other hand, the scaling of the spectra for different glass compositions showed the deviations from the Summerfield scaling because of the local structural disorder which occurs as a result of the structural modifications in the tellurite glass network.

  7. Electrical conduction of glasses in the system Fe2O3-Sb2O3-TeO2; Fe2O3-Sb2O3-TeO2 kei garasu no denki dendo

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Honghua; Mori, H; Sakata, H; Hirayama, T [Tokai Univ., Tokyo (Japan). Faculty of Engineering

    1995-01-01

    In this study, taking into consideration that TeO2 is a component of the glass network and Sb2O3 shows the redox effect in the glasses reducing its possibility of transformation of Sb{sup 3+} to Sb{sup 5+} as well as glass basicity, highly conductive tellurite based glasses have been prepared by the press-quenching method selecting the Fe2O3-Sb2O3-TeO2 system, and the electroconductive mechanism of the glasses has been examined by measuring its D.C. conductivity {sigma}. Part of the obtained information is as follows; the glass formation range of the Fe2O3-Sb2O3-TeO2 system has been 0 {le} Fe2O3 {le} 15mol%, 0 {le} Sb2O3 {le} 18mol% and 78 {le} TeO2 {le} 100mol% and about 15mol% of the additional amount of Fe2O3 has been the limit of glass formation. As the amount of Fe2O3 has increased, C{sub Fe} has also increased and with this, the linear electroconductivity of the glasses has increased from 1.86 {times} 10{sup -7}S{center_dot}cm{sup -1} to 1.62 {times} 10{sup -6}S{center_dot}cm{sup -1} and the glasses have been confirmed as the n-type semiconductor. The factor determining {sigma} of the glasses has been C{sub Fe} which has increased as the amount of Fe2O3 has increased. 34 refs., 8 figs., 2 tabs.

  8. The effect of the H2O/TEOS ratio on the structure of gels derived by the acid catalysed hydrolysis of tetraethoxysilane

    International Nuclear Information System (INIS)

    Strawbridge, I.; James, P.F.; Craievich, A.F.

    1985-01-01

    Silica gels were produced by the acid catalysed hydrolysis of tetraethoxysilane (TEOS) using H 2 O/TEOS ratios from 2 to 50. After heat treatment the structure of the gels was studied using nitrogen adsorption, small angle X-ray scattering (SAXS), transmission electron microscopy (TEM) and bulk density measurements. All the gels possessed microporosity in the region of 30 A or less. For H 2 O/TEOS = 25 and 50 the matrix density was found to be uniform, but for gels from solutions with H 2 O/TEOS = 2, 4 and 10, density fluctuations in the matrix were detected from a Porod analysis of the SAXS data. These results indicate that in high water content solutions, rearrangement of the polymeric chains leads to small densified particles, but for lower water content solutions, gelation results from the entanglement of linear chains leaving free volume on a molecular scale between the chains. (Author) [pt

  9. Attenuation process of the longitudinal phonon mode in a TeO2 crystal in the 20-GHz range

    Science.gov (United States)

    Ohno, S.; Sonehara, T.; Tatsu, E.; Koreeda, A.; Saikan, S.

    2017-06-01

    We experimentally investigated the hypersonic attenuation process of a longitudinal mode (L-mode) sound wave in TeO2 from room temperature to a lower temperature using Brillouin scattering and impulsive stimulated thermal scattering (ISTS) measurements. For precise measurement of the Brillouin linewidth at low temperatures, whereby the mean free path of the phonon becomes longer than the sample length, it is indispensable that the phonon should propagate along the phonon-resonance direction. To figure out the suitable direction, we defined two indices characterizing a degree of phonon divergence and a purity of propagation direction. The best direction that we found from these indices is [110] direction in TeO2, and it was used to discuss the temperature and frequency dependences of Brillouin spectra. We extracted the temperature dependence of the attenuation rate of T4 from the modulated Brillouin spectra due to the phonon resonance below Debye temperature. The frequency dependence ω1 of the hypersonic attenuation was also estimated from the polarization dependence of the Brillouin linewidth. Theoretically, it predicted that the L-mode phonon attenuation at low temperatures in TeO2 is a result of Herring's process, which shows the attenuation behavior of ω2T3 . The ω1T4 dependence is not allowed in Herring's process but is allowed by the L +L →L process, which has been considered to be forbidden so far. We evaluated the thermal phonon lifetime using ISTS and established that it was finite even at 20 K, thereby allowing the L +L →L process. Therefore, we conclude that the L +L →L process dominates the attenuation of an L-mode phonon in TeO2 in the low-temperature region.

  10. SAW propagation characteristics of TeO3/3C-SiC/LiNbO3 layered structure

    Science.gov (United States)

    Soni, Namrata D.

    2018-04-01

    Surface acoustic wave (SAW) devices based on Lithium Niobate (LiNbO3) single crystal are advantageous because of its high SAW phase velocity, electromechanical coupling coefficient and cost effectiveness. In the present work a new multi-layered TeO3/3C-SiC/128° Y-X LiNbO3 SAW device has been proposed. SAW propagation properties such as phase velocity, coupling coefficient and temperature coefficient of delay (TCD) of the TeO3/SiC/128° Y-X LiNbO3 multi layered structure is examined using theoretical calculations. It is found that the integration of 0.09λ thick 3C-SiC over layer on 128° Y-X LiNbO3 increases its electromechanical coupling coefficient from 5.3% to 9.77% and SAW velocity from 3800 ms‑1 to 4394 ms‑1. The SiC/128° Y-X LiNbO3 bilayer SAW structure exhibits a high positive TCD value. A temperature stable layered SAW device could be obtained with introduction of 0.007λ TeO3 over layer on SiC/128° Y-X LiNbO3 bilayer structure without sacrificing the efficiency of the device. The proposed TeO3/3C-SiC/128° Y-X LiNbO3 multi-layered SAW structure is found to be cost effective, efficient, temperature stable and suitable for high frequency application in harsh environment.

  11. Bingham viscosity and yield stress of molten (TeO2)0.78(WO3)0.22 glass

    International Nuclear Information System (INIS)

    Churbanov, M.F.; Snopatin, G.E.; Shaposhnikov, R.M.; Shabarov, V.V.; Plotnichenko, V.G.

    2007-01-01

    The flow of molten (TeO 2 ) 0.78 (WO 3 ) 0.22 glass in a circular-cylindrical channel has been studied at temperatures from 390 to 430 deg C. The variation of the measured volumetric flow rate with the gas pressure over the melt attests to non-Newtonian flow behavior. The flow rates calculated in the pseudo plastic model were used to determine the yield stress and plastic (Bingham) viscosity of the melt [ru

  12. Synthesis and electrochemical study of a hybrid structure based on PDMS-TEOS and titania nanotubes for biomedical applications

    International Nuclear Information System (INIS)

    Castro, António G B; Bastos, Alexandre C; Miranda Salvado, Isabel M; Galstyan, Vardan; Faglia, Guido; Sberveglieri, Giorgio

    2014-01-01

    Metallic implants and devices are widely used in the orthopedic and orthodontic clinical areas. However, several problems regarding their adhesion with the living tissues and inflammatory responses due to the release of metallic ions to the medium have been reported. The modification of the metallic surfaces and the use of biocompatible protective coatings are two approaches to solve such issues. In this study, in order to improve the adhesion properties and to increase the corrosion resistance of metallic Ti substrates we have obtained a hybrid structure based on TiO 2 nanotubular arrays and PDMS-TEOS films. TiO 2 nanotubes have been prepared with two different diameters by means of electrochemical anodization. PDMS-TEOS films have been prepared by the sol–gel method. The morphological and the elemental analysis of the structures have been investigated by scanning electron microscopy and energy dispersive spectroscopy (EDS). Electrochemical impedance spectroscopy (EIS) and polarization curves have been performed during immersion of the samples in Kokubo’s simulated body fluid (SBF) at 37 °C to study the effect of structure layers and tube diameter on the protective properties. The obtained results show that the modification of the surface structure of TiO 2 and the application of PDMS-TEOS film is a promising strategy for the development of implant materials. (paper)

  13. Enriched TeO2 bolometers with active particle discrimination: Towards the CUPID experiment

    Directory of Open Access Journals (Sweden)

    D.R. Artusa

    2017-04-01

    Full Text Available We present the performances of two 92% enriched 130TeO2 crystals operated as thermal bolometers in view of a next generation experiment to search for neutrinoless double beta decay of 130Te. The crystals, 435 g each, show an energy resolution, evaluated at the 2615 keV γ-line of 208Tl, of 6.5 and 4.3 keV FWHM. The only observable internal radioactive contamination arises from 238U (15 and 8 μBq/kg, respectively. The internal activity of the most problematic nuclei for neutrinoless double beta decay, 226Ra and 228Th, are both evaluated as <3.1 μBq/kg for one crystal and <2.3 μBq/kg for the second. Thanks to the readout of the weak Cherenkov light emitted by β/γ particles by means of Neganov–Luke bolometric light detectors we were able to perform an event-by-event identification of β/γ events with a 95% acceptance level, while establishing a rejection factor of 98.21% and 99.99% for α particles.

  14. Identity and Friendship in Hsu-Ming Teo´s Behind the Moon (2000

    Directory of Open Access Journals (Sweden)

    Catalina Ribas Segura

    2015-03-01

    Full Text Available In her second novel, Behind the Moon (2000, Hsu-Ming Teo explores the identity construction of three teenage friends and how they defy the notion of the „ideal‟ Australian as a heterosexual, Protestant, white, English-speaking, Australian-born of British ancestry young adult person. Set in the western suburbs of Sydney in the 1990s, the three friends are an example of the multicultural society of the time: Justin Cheong, the son of a Chinese-Singaporean family who arrived in Australia with the Business Migration Programme; Tien Ho, a refugee girl of Chinese-Vietnamese and Afro-CajunCreole-American ancestry; and Nigel „Gibbo‟ Gibson, the son of an Anglo-Australian father and an English mother. The novel tackles different relations among these characters and their families during their teenage years and especially as young adults. This paper seeks to analyse the evolution of the identities of Justin, Tien and „Gibbo‟ through the notions of belonging, gender construction and sexuality. In order to do so, the main theories applied will be the insights on homosexuality and on masculinities of Maria Pallotta-Chiarolli (1995 and Raewyn W. Connell (1995 and Manuel Castellsʼ (2010 identity construction theory

  15. Visible light driven multifunctional photocatalysis in TeO2-based semiconductor glass ceramics

    Science.gov (United States)

    Kushwaha, Himmat Singh; Thomas, Paramanandam; Vaish, Rahul

    2017-01-01

    Photocatalytic xCaCu3Ti4O12-(100-x)TeO2 (x=0.25 mol% to 3 mol%), glass nanocomposites were fabricated and investigated for wastewater treatment, self-cleaning surfaces, and photocatalytic hydrogen evolution. Visible light active crystals of Cu-doped TiO2 and TiTe3O8 were grown by optimized crystallization of as-quenched glasses. The visible light photocatalytic activity of glass samples was investigated for estrogenic pharmaceutical pollutants, and the degradation rate was obtained as 168.56 min-1 m-2. A higher photocatalytic H2 production rate was observed (135 μmole h-1 g-1) for the crystallized CaCu3Ti4O12-TeO2 (x=3. 0) glass plate under visible light. The self-cleaning performance was observed using contact angle measurements for water under dark and light conditions. These visible light active glass ceramics are a cost effective sustainable solution for water treatment and self-cleaning applications.

  16. Competitive Adsorption and Oxidation Behavior of Heavy Metals on nZVI Coated with TEOS.

    Science.gov (United States)

    Eglal, Mahmoud M; Ramamurthy, Amruthur S

    2015-11-01

    Zero valent iron nanoparticle (nanofer ZVI) is a powerful substance due to its coating with tetraethyl orthosilicate (TEOS). Tetraethyl orthosilicate imparts higher reactivity and decreases particle agglomeration. The competitive removal and displacement of multi-metals are influenced by time, pH, and initial concentration, the presence and properties of competing metals ion in the solution. For both the isotherm and kinetic studies performed for multi-metal removal experiments, compared to Pb II and Cd II, Cu II experienced a higher removal rate during the initial 5 minutes. After 120 minutes, all metals achieved removal efficiency in the range of 95 to 99%. The results of single and competitive kinetic tests for all three metals during the initial 5 minutes indicated that the presence of other metals generally reduce removal efficiency of metals. Both kinetic test and electron dispersive spectroscope (EDS) studies found that Cu II gets removed faster than the other metals. Pseudo-second order behavior was noted for the multi-metal removal systems.

  17. Correction of Visual Perception Based on Neuro-Fuzzy Learning for the Humanoid Robot TEO

    Directory of Open Access Journals (Sweden)

    Juan Hernandez-Vicen

    2018-03-01

    Full Text Available New applications related to robotic manipulation or transportation tasks, with or without physical grasping, are continuously being developed. To perform these activities, the robot takes advantage of different kinds of perceptions. One of the key perceptions in robotics is vision. However, some problems related to image processing makes the application of visual information within robot control algorithms difficult. Camera-based systems have inherent errors that affect the quality and reliability of the information obtained. The need of correcting image distortion slows down image parameter computing, which decreases performance of control algorithms. In this paper, a new approach to correcting several sources of visual distortions on images in only one computing step is proposed. The goal of this system/algorithm is the computation of the tilt angle of an object transported by a robot, minimizing image inherent errors and increasing computing speed. After capturing the image, the computer system extracts the angle using a Fuzzy filter that corrects at the same time all possible distortions, obtaining the real angle in only one processing step. This filter has been developed by the means of Neuro-Fuzzy learning techniques, using datasets with information obtained from real experiments. In this way, the computing time has been decreased and the performance of the application has been improved. The resulting algorithm has been tried out experimentally in robot transportation tasks in the humanoid robot TEO (Task Environment Operator from the University Carlos III of Madrid.

  18. Phase Equilibria Study in the TeO2-Na2O-SiO2 System in Air Between 723 K (500 °C) and 1473 K (1200 °C)

    Science.gov (United States)

    Santoso, Imam; Taskinen, Pekka

    2016-08-01

    Knowledge of phase equilibria in the TeO2-Na2O-SiO2 system at elevated temperatures is important for ceramic and glass industries and for improving the operation of the smelting process of tellurium-containing materials. A review of previous investigations has indicated, however, that there are omissions in the available datasets on the liquidus temperatures of the molten TeO2-Na2O-SiO2 mixtures. The employed experimental method included equilibration of mixtures made from high purity oxides, rapid quenching of the equilibrated samples in water and followed by compositional analysis of the phases using an electron probe X-ray microanalyzer. The liquidus and phase equilibria in the TeO2-SiO2, TeO2-Na2O, and SiO2-TeO2-Na2O systems have been studied for a wide range of compositions between 723 K (500 °C) and 1473 K (1200 °C) at TeO2, SiO2, and Na2SiO3 saturations. New data have been generated in the SiO2-TeO2-Na2O system at SiO2 saturation. The liquidus compositions in the TeO2-Na2O system at TeO2 saturation have been compared with the previous data and an assessed phase diagram.

  19. Propriedades estruturais e térmicas de vidros teluretos 20Li2O-80TeO2 Structural and thermal properties of tellurite 20Li2O-80TeO2 glasses

    Directory of Open Access Journals (Sweden)

    E. Idalgo

    2007-09-01

    Full Text Available O presente trabalho reporta estudos sobre a cristalização em vidros teluretos 20Li2O-80TeO2 induzida a partir de tratamentos térmicos realizados sobre vidros com tamanho de partículas entre 38 µm e 75 µm. Estes estudos foram conduzidos em duas matrizes vítreas tratadas e não tratadas termicamente para aliviar as tensões após o quenching, utilizando-se de forma combinada às técnicas de difração de raios X, calorimetria diferencial de varredura e espectroscopia no infravermelho. Os resultados revelaram a presença de três fases cristalinas distintas durante o processo de cristalização e apontaram para uma hierarquia tal que as fases alfa-TeO2 e gama-TeO2 cristalizam-se antecipadamente à fase Li2Te2O5 no vidro 20Li2O-80TeO2 sujeito a tensões mecânicas induzidas durante a síntese. No vidro 20Li2O-80TeO2, livre de tensões mecânicas, não foi possível discriminar esta hierarquia de cristalização.This work report crystallization studies on tellurite 20Li2O-80TeO2 glasses induced from heat thermal annealing on glasses with particle size between 38 µm and 75 µm. These studies were conducted on two glass matrix heat thermal annealed and non-annealed to remove the stress after the quenching, by using the X-Ray diffraction analysis, Fourier transform infrared spectroscopy and differential scanning calorimetry techniques. The results shown the presence of three distinct crystalline alpha-TeO2, gamma-TeO2 and Li2Te2O5 phases during the crystallization process, suggesting a crystallization hierarchy on the glass matrix under stress, since the gamma-TeO2 and alpha-TeO2 phases crystallization occurs before the Li2Te2O5 phase. On the glass stress free, this crystallization hierarchy was not clearly determined.

  20. Examination of adhesion layer of TeO2 film with indented platinum substrate after radiation loading by 13 MeV deuterons

    International Nuclear Information System (INIS)

    Garapatskij, A.A.; Troyan, P.E.

    2011-01-01

    In this work the influence of a corrugated surface of a Pt substrate on the quality of thermal contact of an adhesion layer with a material of different compositions of TeO 2 and Al 2 O 3 when bombing a target by a 20 µA, 13.7 MeV deuteron beam has been studied. Before the irradiation a Raman spectrum of the TeO 2 +4%Al 2 O 3 material had a fuzzy contour, what corresponds to a polycrystalline composition or glass, but after the irradiation the spectrum has distinct Raman peaks which relate to the α-phase. In Raman spectrums for TeO 2 , containing α-phase peaks, essential changes were not observed after the irradiation. However, the glassy structure was formed in the target’s central part. Studies have shown good thermal contact of TeO 2 with the surface of a Pt substrate, processed by the offered technique. It allows to manage without addition of Al 2 O 3 and to carry out the target irradiation without loss of TeO 2 . (authors)

  1. Evaluation of tetraethoxysilane (TEOS) sol–gel coatings, modified with green synthesized zinc oxide nanoparticles for combating microfouling

    Energy Technology Data Exchange (ETDEWEB)

    Krupa, A. Nithya Deva; Vimala, R., E-mail: vimala.r@vit.ac.in

    2016-04-01

    Green synthesis of zinc oxide nanoparticles (ZnO-NPs) is gaining importance as an eco-friendly alternative to conventional methods due to its enormous applications. The present work reports the synthesis of ZnO-NPs using the endosperm of Cocos nucifera (coconut water) and the bio-molecules responsible for nanoparticle formation have been identified. The synthesized nanoparticles were characterized using UV–Visible spectroscopy (UV–Vis), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Transmission Electron Microscopy (TEM) and Zeta potential measurement. The results obtained reveal that the synthesized nanoparticles are moderately stable with the size ranging from 20 to 80 nm. The bactericidal effect of the nanoparticles was proved by well diffusion assay and determination of minimum inhibitory concentration (MIC) against marine biofilm forming bacteria. Further the green synthesized ZnO-NPs were doped with TEOS sol–gels (TESGs) in order to assess their antimicrofouling capability. Different volumes of liquid sol–gels were coated on to 96-well microtitre plate and cured under various conditions. The optimum curing conditions were found to be temperature 60 °C, time 72 h and volume 200 μl. Antiadhesion test of the undoped (SG) and ZnO-NP doped TEOS sol–gel (ZNSG) coatings were evaluated using marine biofilm forming bacteria. ZNSG coatings exhibited highest biofilm inhibition (89.2%) represented by lowest OD value against Pseudomonasotitidis strain NV1. - Highlights: • The study reports low cost, and simple procedure for the synthesis of ZnO-NPs using coconut water. • XRD result shows the high crystalline nature of the synthesized ZnO-NPs. • TEM and zeta potential distribution confirms the nanostructure, stability of the synthesized ZnO-NPs. • ZnO-NPs doped with TEOS sol¬-gels (TESGs) exhibited excellent antimicrofouling activity.

  2. Growth and Characteristic of Amorphous Nano-Granular TeO2-V2O5-NiO Thin Films

    Science.gov (United States)

    Hosseinzadeh, Sh.; Rahmati, A.; Bidadi, H.

    2016-12-01

    TeO2-V2O5-NiO thin films were deposited using thermal evaporation from 40TeO2-(60-y)V2O5-yNiO (y=0-30mol%) target. Structural analysis of the films was identified by X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The amorphous TeO2-V2O5-NiO films have nanosized clear grain structure and sharp grain boundaries. DC conductivity and current-voltage (I-V) characteristic of TeO2-V2O5-NiO thin films were measured in the temperature range of 300-423K. As nickel oxide (NiO) content increases, the DC conductivity decreases up to two orders in value (10-9-10-11Sṡcm-1). Temperature dependence of conductivity is described using the small polaron hopping (SPH) model as well. Poole-Frenkel effect is observed at high external electric field. The optical absorption spectra of the TeO2-V2O5-NiO thin films were recorded in the wavelength range of 380-1100nm. The absorption coefficient revealed bandgap shrinkage (3.01-2.3eV) and band tail widening, due to an increase in NiO content. Energy dispersive X-ray spectroscopy (EDX) was used to determine elemental composition. In TeO2-V2O5-NiO thin films, the NiO content is around fifth of the initial target.

  3. In situ mid-infrared analyses of reactive gas-phase intermediates in TEOS/Ozone SAPCVD

    International Nuclear Information System (INIS)

    Whidden, Thomas K.; Doiron, Sarah

    1998-01-01

    In this report, we present in situ characterizations of chemical vapour deposition (CVD) reactors used in silicon dioxide thin film depositions. The characterizations are based on Fourier transform infrared spectroscopy. The infrared absorption data are interpreted within the context of process and thin film properties and the bearing of the spectroscopic data upon the chemical mechanisms extant in the deposition reaction. The relevance of the interpretations to real-time process control is discussed. The process under study in this work is TEOS/ozone-based deposition of silicon dioxide thin films at subatmospheric pressures. This process exhibits many desirable properties but has fundamental problems that may be solvable by reaction control based on in situ analyses and the real-time manipulation of reagent concentrations and process conditions. Herein we discuss our preliminary data on characterizations of TEOS/ozone chemistries in commercial reactor configurations. Reaction products and reactive intermediate species are detected and identified. Quantitative in situ measurements of the reagent materials are demonstrated. Preliminary correlations of these data with process and thin film properties are discussed

  4. In vitro genotoxicity assessment of MTES, GPTES and TEOS, three precursors intended for use in food contact coatings.

    Science.gov (United States)

    Lionti, Krystelle; Séverin, Isabelle; Dahbi, Laurence; Toury, Bérangère; Chagnon, Marie-Christine

    2014-03-01

    Organoalkoxysilanes are precursors that are used increasingly in the synthesis of food contact coatings. To comply with the EU regulation, their potential toxicity must be assessed, and very little information is known. The genotoxicity of three common precursors was studied, namely, tetraethylorthosilicate (TEOS), methyltriethoxysilane (MTES) and 3-glycidyloxypropyltriethoxysilane (GPTES). By the Ames test, MTES and TEOS were not mutagenic for bacteria. A significant positive response was observed with GPTES in the TA100 and TA1535 strains. The mutagenic effect was more pronounced in the presence of the exogenous metabolic activation system with an increase of the induction factor (ten-fold higher for the TA1535 strain). In the micronucleus assay performed with a human hepatoma cell line (HepG2 cells), GPTES gave negative results even in the presence of an exogenous activation system. To ascertain the possibility of using this precursor in food contact material, its migration must be monitored according to the coating formulation because migration might result in hazardous human exposure. Copyright © 2014. Published by Elsevier Ltd.

  5. Preparation and characterization of new glasses from the TeO2-CdO-Al2O3-SiO2 system

    OpenAIRE

    Zayas, Mª. E.; Espinoza-Beltrán, F. J.; Romero, Maximina; Rincón López, Jesús María

    1998-01-01

    A new family of glasses from the TeO2-CdO-Al2O3-SiO2 system obtained from CdS-TeO2 mixtures melted in fireclay crucibles have been prepared and characterized. The density values of these glasses are in the 3.30-3.46 gcm-3 range. The viscosity-temperature variation shows that glasses with high TeO2 content depict the typical variation of `short glasses' for a molding operation. Microstructural observations by TEM (replica method) and SEM microscopies have shown that these glasses contain very ...

  6. Vascularização arterial e venosa do linfonodo poplíteo em cães

    Directory of Open Access Journals (Sweden)

    Karina de Senna Villar

    2009-08-01

    Full Text Available O linfonodo poplíteo nos cães situa-se, à direita e à esquerda em um espaço designado fossa poplítea, no terço distal dos músculos bíceps femoral, lateralmente e semitendinoso, medialmente, projetando-se na altura da face caudal das articulações femoro tibial e femoro patelar (articulação do joelho. Neste estudo foram utilizados vinte e cinco cães, machos e fêmeas adultos, procedentes do canil municipal de Araçatuba, São Paulo, cujas capturas foram efetuadas pela defesa sanitária animal desta cidade. Os vasos arteriais destinados a esta estrutura derivam sempre, de ambos os lados, da artéria femoral caudal distal e variam de 10 a 1, com maior freqüência de 2 (7 vezes, 28% à direita e de 6 a 2 igualmente com maior freqüência de 2 (8 vezes, 32%. Tão logo tem-se ainda à direita 5 e 6 ramos (3 vezes, 12%, 1, 7 e 10 (1 vez, 4%. Relativamente às veias derivadas deste linfonodo, convergem sempre para a veia safena lateral, estes vasos oscilam entre 9 e 2, com maior freqüência de 3 (9 vezes, 3,6%, à direita e de 12 a 2, com maior freqüência de 3 (10 vezes, 40% à esquerda. Assim, os demais ramos oriundos da linfonodo poplíteo direito e que se inserem na veia supracitada são em número de 2 e 5 (5 vezes, 20%, 4 e 6 (2 vezes, 8% e 8 e 9 (1 vez, 4%. Não obstante, ao lado esquerdo verifica-se em número de 2 ramos (6 vezes, 24%, 4 (4 vezes, 16%, 6 (3 vezes, 12% e finalizando 9 e 12 ramos (1 vez, 4%. O tamanho do linfonodo poplíteo em cães soropositivos para Leishmaniose Visceral pode encontrar-se entre 7,8 x 3,8 x 6,1 a 50,0 x 20,7 x 28,5 , em mm, sendo a média 26,18 x 10,5 x 15,97 mm para o direito e 26,98 x 11,14 x 15,25 mm para o esquerdo (referente as medidas dorso-ventral, latero-lateral e crânio-caudal, respectivamente.

  7. Muusikamaailm : Arvo Pärdi uus teos. Telemanni päevad Magdeburgis. Uus orkester Soomes. Ingvar Lidholm 80. Auhindu ja preemiaid / Priit Kuusk

    Index Scriptorium Estoniae

    Kuusk, Priit, 1938-

    2001-01-01

    21. veebr. tuli Oxfordis maailmaesiettekandele A. Pärdi teos "Littlemore Tractus". Telemanni päevade raames toimuvast rahvusvahelisest kammeransamblite konkursist Magdeburgis. O. Mustonen asutas Helsingis uue orkestri. Lühidalt I.Lidholmi tegevusest ja loomingust. P. Norgaardile ja H. von Manen'ile antud autasust ja preemiast

  8. Muusika : Chopiniئvirtuoos ERSO ees. Teo Maiste 70. Virumaa noorteorkestri sünnipäev. "Jazzkaare" festivali peaesinejad. Kuningas Arthuri Gala 2002

    Index Scriptorium Estoniae

    2002-01-01

    Koos ERSOga astub üles poola tipp-pianist. Teo Maiste tähistab 70ndat juubelit laval. Virumaa noorteorkestr sai viie aastaseks. "Jazzkaare" festivali peaesinejateks on USA lauljatar-pianist Diane Schuur ja norra klahvpillimängija Bugge Wessetoft. Seekordne Kuningas Arthuri Gala 2002 toimub Narva Aleksandri kirikus

  9. Conservation of Monuments by a Three-Layered Compatible Treatment of TEOS-Nano-Calcium Oxalate Consolidant and TEOS-PDMS-TiO2 Hydrophobic/Photoactive Hybrid Nanomaterials

    Directory of Open Access Journals (Sweden)

    Chrysi Kapridaki

    2018-04-01

    Full Text Available In the conservation of monuments, research on innovative nanocomposites with strengthening, hydrophobic and self-cleaning properties have attracted the interest of the scientific community and promising results have been obtained as a result. In this study, stemming from the need for the compatibility of treatments in terms of nanocomposite/substrate, a three-layered compatible treatment providing strengthening, hydrophobic, and self-cleaning properties is proposed. This conservation approach was implemented treating lithotypes and mortars of different porosity and petrographic characteristics with a three-layered treatment comprising: (a a consolidant, tetraethoxysilane (TEOS-nano-Calcium Oxalate; (b a hydrophobic layer of TEOS-polydimethylsiloxane (PDMS; and (c a self-cleaning layer of TiO2 nanoparticles from titanium tetra-isopropoxide with oxalic acid as hole-scavenger. After the three-layered treatment, the surface hydrophobicity was improved due to PDMS and nano-TiO2 in the interface substrate/atmosphere, as proven by the homogeneity and the Si–O–Ti hetero-linkages of the blend protective/self-cleaning layers observed by Scanning Electron Microscope (SEM, Transmission Electron Microscope (TEM and Fourier-Transform Infrared Spectroscopy (FTIR. The aesthetic, microstructural, mechanical and permeabile compatibility of the majority of treated substrates ranged within acceptability limits. The improved photocatalytic activity, as proven by the total discoloration of methylene blue in the majority of cases, was attributed to the anchorage of TiO2, through the Si–O–Ti bonds to SiO2, in the interface with the atmosphere, thus enhancing photoactivation.

  10. Hyper-spectral modulation fluorescent imaging using double acousto-optical tunable filter based on TeO2-crystals

    International Nuclear Information System (INIS)

    Zaytsev, Kirill I; Perchik, Alexey V; Chernomyrdin, Nikita V; Yurchenko, Stanislav O; Kudrin, Konstantin G; Reshetov, Igor V

    2015-01-01

    We have proposed a method for hyper-spectral fluorescent imaging based on acousto-optical filtering. The object of interest was pumped using ultraviolet radiation of mercury lamp equipped with monochromatic excitation filter with the window of transparency centered at 365 nm. Double TeO 2 -based acousto-optical filter, tunable in range from 430 to 780 nm and having 2 nm bandwidth of spectral transparency, was used in order to detect quasimonochromatic images of object fluorescence. Modulating of ultraviolet pump intensity was used in order to reduce an impact of non-fluorescent background on the sample fluorescent imaging. The technique for signal-to-noise ratio improvement, based on fluorescence intensity estimation via digital processing of modulated video sequence of fluorescent object, was introduced. We have implemented the proposed technique for the test sample studying and we have discussed its possible applications

  11. Random laser emission from a Rhodamine B-doped GPTS/TEOS-derived organic/silica monolithic xerogel

    Science.gov (United States)

    Abegão, Luis M. G.; Manoel, D. S.; Otuka, A. J. G.; Ferreira, P. H. D.; Vollet, D. R.; Donatti, D. A.; De Boni, L.; Mendonça, C. R.; De Vicente, F. S.; Rodrigues, J. J., Jr.; Alencar, M. A. R. C.

    2017-06-01

    A Rhodamine B-doped 3-glycidoxypropyltrimethoxysilane (GPTS)/tetraethyl orthosilicate (TEOS)-derived organic/silica monolithic xerogel with excellent optical properties was prepared and its potential as a random laser host investigated. This hybrid material has a non-porous organic/inorganic morphology with silica-rich nanoparticles of less than 10 nm in diameter homogeneously dispersed within the matrix. Random laser emission with incoherent feedback, centered at 618 nm, was observed from Rhodamine B incorporated into the monolithic xerogel when excited by a 532 nm pulsed laser. This hybrid system is shown to be very promising for the development of a new class of random laser-based integrated devices, with applications ranging from optical bio-imaging to sensing.

  12. Synthesis and Optical Characterization of Nd3+ doped TeO2-PbO-Li2O

    Directory of Open Access Journals (Sweden)

    M. Rahim Sahar

    2012-02-01

    Full Text Available Glass based on Nd3+-doped TeO2-PbO-Li2O has successfully been made by melt quenching technique and their thermal parameters have been determined using Differential Thermal Analyzer (DTA. The glass is then nucleated and/or growth by controlled heat treatment at slightly below the crystallization temperature. The X-ray diffraction (XRD technique is used to estimate the nano-crystallite size. Meanwhile, the optical characterization has been determined using the Photoluminescence Spectroscopy. It is found out that the crystallite size is about 20 nm and very much depending on the heat-treatment time. Meanwhile, the intensity of the luminescence spectra is very much depending on the concentration of the dopant.   Keyword: tellurium glasses, melt quenching technique, optical characterization

  13. Optical transitions of Er3+/Yb3+ codoped TeO2-WO3-Bi2O3 glass.

    Science.gov (United States)

    Shen, Xiang; Nie, Qiuhua; Xu, Tiefeng; Gao, Yuan

    2005-10-01

    Optical absorption and emission properties of the Er3+/Yb3+ codoped TeO2-WO3-Bi2O3 (TWB) glass has been investigated. The transition probabilities, excited state lifetimes, and the branching ratios have been predicted for Er3+ based on the Judd-Ofelt theory. The broad 1.5 microm fluorescence was observed under 970 nm excitation, and its full width at half maximum (FWHM) is 77 nm. The emission cross-section is calculated using the McCumber theory, and the peak emission cross-section is 1.03 x 10(-21) cm2 at 1.531 microm. This value is much larger than those of the silicate and phosphate glasses. Efficient green and weak red upconversion luminescence from Er3+ centers in the glass sample was observed at room temperature, and the upconversion excitation processes have been analyzed.

  14. Spectroscopy and visible frequency upconversion in Er3+-Yb3+: TeO2-ZnO glass.

    Science.gov (United States)

    Mohanty, Deepak Kumar; Rai, Vineet Kumar

    2014-01-01

    The UV-Vis-NIR absorption studies of the Er(3+)/Er(3+)-Yb(3+) doped/codoped TeO2-ZnO (TZO) glasses fabricated by the melting and quenching method has been performed. The spectroscopic radiative parameters viz. radiative transition probabilities, branching ratios and lifetimes have been determined from the absorption spectrum by using Judd-Ofelt theory. The near infrared (NIR) to visible frequency upconversion (UC) have been monitored by using an excitation of 976 nm wavelength radiation from a CW diode laser. The effect of codoping with Yb(3+) ions on the intensity of the UC emission bands from the Er(3+) ions throughout visible region has been studied. The mechanism responsible for the observed upconversion emissions in the prepared samples have been explained on the basis of excited state absorption and efficient energy transfer processes. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Characterization of emission properties of Er3+ ions in TeO2-CdF2-WO3 glasses.

    Science.gov (United States)

    Bilir, G; Mustafaoglu, N; Ozen, G; DiBartolo, B

    2011-12-01

    TeO(2)-CdF(2)-WO(3) glasses with various compositions and Er(3+) concentrations were prepared by conventional melting method. Their optical properties were studied by measuring the absorption, luminescence spectra and the decay patterns at room temperature. From the optical absorption spectra the Judd-Ofelt parameters (Ω(t)), transition probabilities, branching ratios of various transitions, and radiative lifetimes were calculated. The absorption and emission cross-section spectra of the (4)I(15/2) to (4)I(13/2) transition of erbium were determined. Emission quantum efficiencies and the average critical distance R(0) which provides a measure for the strength of cross relaxation were determined. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Transanal endoscopic microsurgery with 3-D (TEM) or high-definition 2-D transanal endoscopic operation (TEO) for rectal tumors. A prospective, randomized clinical trial.

    Science.gov (United States)

    Serra-Aracil, Xavier; Mora-Lopez, Laura; Alcantara-Moral, Manel; Caro-Tarrago, Aleidis; Navarro-Soto, Salvador

    2014-05-01

    Transanal endoscopic microsurgery (TEM) is a three-dimensional viewing endoscopic system procedure which provides access to rectal tumors through a rectoscope. Two-dimensional transanal endoscopic operation (TEO), with the introduction of high-definition vision, achieves results that are comparable to those of the classical TEM. The main aim of the study was to compare the effectiveness of TEO and TEM systems in a prospective, randomized clinical trial. patients meeting inclusion criteria for diagnosis of rectal tumors with curative intent. Sample size, 36 patients. Patients were randomized to receive one of the two procedures. Study variables recorded were the following: preoperative data (time taken to assemble equipment, surgical time, quality of pneumorectum), postoperative morbidity and mortality, pathology study of the tumors, and economic analysis. Thirty-six patients were analyzed according to intention to treat. Two patients were excluded. The final per-protocol analysis was 34 patients. There were no significant differences in the preoperative or operative variables, quality of pneumorectum, postoperative variables, or pathology results. A trend toward benefit was observed in favor of TEO in time required for assembly, surgical suture time, and total surgical time though the differences were not statistically significant. Statistically significant differences were found in terms of the total cost of the procedure, with mean costs of 2,031  ± 440 for TEO and 2,603  ± 507 for TEM (95% CI 218.15-926.486 , p = 0.003). No technical or clinical differences were observed between the results obtained with the two systems except lower cost with TEO.

  17. Cs7Sm11[TeO3]12Cl16 and Rb7Nd11[TeO3]12Br16, the new tellurite halides of the tetragonal Rb6LiNd11[SeO3]12Cl16 structure type

    Science.gov (United States)

    Charkin, Dmitri O.; Black, Cameron; Downie, Lewis J.; Sklovsky, Dmitry E.; Berdonosov, Peter S.; Olenev, Andrei V.; Zhou, Wuzong; Lightfoot, Philip; Dolgikh, Valery A.

    2015-12-01

    Two new rare-earth - alkali - tellurium oxide halides were synthesized by a salt flux technique and characterized by single-crystal X-ray diffraction. The structures of the new compounds Cs7Sm11[TeO3]12Cl16 (I) and Rb7Nd11[TeO3]12Br16 (II) (both tetragonal, space group I4/mcm) correspond to the sequence of [MLn11(TeO3)12] and [M6X16] layers and bear very strong similarities to those of known selenite analogs. We discuss the trends in similarities and differences in compositions and structural details between the Se and Te compounds; more members of the family are predicted.

  18. Töölepingu lõpetamine töötaja süüteo tõttu : [bakalaureusetöö] / Marili Lämmergas ; Tartu Ülikooli Õigusinstituut ; juhendaja: Heino Siigur

    Index Scriptorium Estoniae

    Lämmergas, Marili

    2005-01-01

    Töötaja töökohustused, töölepingu lõpetamine töötajapoolsel töökohustuste rikkumisel, töötaja suhtes usalduse kaotamisel, töötaja vääritu teo tõttu, vorminõuete rikkumine ja asjaolude tõendamine töölepingu lõpetamisel töötaja süüteo tõttu

  19. Structural, thermal and optical properties of TeO2-ZnO-CdO-BaO glasses doped with VO(2+).

    Science.gov (United States)

    Sreenivasulu, V; Upender, G; Chandra Mouli, V; Prasad, M

    2015-09-05

    The glasses with composition 64TeO2-15ZnO-(20-x)CdO-xBaO-1V2O5 (0⩽x⩽20 mol%) were prepared by conventional melt quenching technique. X-ray diffraction analysis was used to confirm the amorphous nature of the glasses. The optical absorption studies revealed that the cut-off wavelength (λα) decreases while optical band gap energy (Eopt) and Urbach energy (ΔE) values increase with an increase of BaO content. Refractive index (n) evaluated from Eopt was found to decrease with an increase of BaO content. The physical parameters such as density (ρ), molar volume (Vm), oxygen packing density (OPD), optical basicity (Λ), molar refraction (Rm), and metallization criterion (M) evaluated and discussed. FTIR and Raman spectroscopic studies showed that the glass network consists of TeO4, TeO3+1/TeO3 and ZnO4 units as basic structural units. The glass transition temperature (Tg) of glass sample, onset crystallization temperature (To) and thermal stability ΔT were determined from Differential Scanning Calorimetry (DSC). Using electron paramagnetic resonance (EPR) spectra of vanadium glasses the spin Hamiltonian parameters and dipolar hyperfine coupling parameters of VO(2+) ions were calculated. It was found that V(4+) ions in these glasses exist as VO(2+) in octahedral coordination with a tetragonal distortion and have C4V symmetry with ground state dxy. Tetragonality (Δg∥/Δg⊥) of vanadium ion sites exhibited non-linear variation with BaO content. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Thermal, structural and optical properties of new TeO2sbnd Sb2O3sbnd GeO2 ternary glasses

    Science.gov (United States)

    Pereira, C.; Barbosa, J.; Cassanjes, F. C.; Gonçalves, R. R.; Ribeiro, S. J. L.; Poirier, G.

    2016-12-01

    In this work the novel glass system TeO2sbnd Sb2O3sbnd GeO2 was investigated and promising glass compositions were selected for further specific studies. Glass samples in the (80-0.8x)TeO2-(20-0.2x)Sb2O3-xGeO2 molar composition were prepared by the melt-quenching method with a glass-forming domain from x = 10 to x = 90. Samples were investigated by XRD, DSC, FTIR, Raman spectroscopy and UV-visible absorption. The XRD and DSC results bring informations about the non-crystalline state and thermal properties of these materials. It has been observed that higher GeO2 contents lead to higher glass transition temperatures and thermal stabilities against crystallization. FTIR and Raman spectroscopies suggest a progressive incorporation of GeO2 in the covalent network of TeO2 with conversion of structural units TeO4 to TeO3. Absorption spectra revealed the high visible transparency of these samples and an increase of the optical band gap with GeO2 addition, in agreement with a decreasing polarizability of the glass network. Er3+ doped and Er3+/Yb3+ codoped samples were also studied with respect to their infrared emission properties and higher GeO2 contents lead to an increase in IR emission intensity at 1,5 μm as well as longer radiative lifetimes. Finally, upconversion emission in the visible were also recorded and were shown to be strongly dependent of the composition.

  1. Raman spectroscopy, thermal and optical properties of TeO2-ZnO-Nb2O5-Nd2O3 glasses.

    Science.gov (United States)

    Kamalaker, V; Upender, G; Ramesh, Ch; Mouli, V Chandra

    2012-04-01

    The glasses with composition 75TeO2-10ZnO-(15-x)Nb2O5-xNd2O3 (0≤x≤9 mol%) were prepared using melt quenching method and their physical properties such as density (ρ), molar volume (VM), average crosslink density (nc¯), oxygen packing density (OPD) and number of bonds per unit volume (nb) were determined. Raman spectroscopic studies showed that the glass network consists of TeO4, TeO3+1, TeO3 and NbO6 units as basic structural units. The glass transition temperature (Tg), crystallization onset (To) and thermal stability (ΔT) were determined from DSC thermograms. The Raman and DSC results were found to be correlated with the physical properties. In the optical absorption spectra six absorption bands were observed with different relative intensities at around 464, 522, 576, 742, 801 and 871 nm which are assigned to the transition of electrons from (ground state) 4I9/2→G11/2; 4I9/2→2K3/2, 2G7/2; 4I9/2→4G5/2, 4G7/2; 4I9/2→4S3/2; 4F7/2→2H9/2, 4F5/2 and 4I9/2→2F3/2 respectively. From optical absorption data the energy band gap (Eopt) and Urbach energy (ΔE) were calculated. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Ho3+-doped AlF3-TeO2-based glass fibers for 2.1 µm laser applications

    Science.gov (United States)

    Wang, S. B.; Jia, Z. X.; Yao, C. F.; Ohishi, Y.; Qin, G. S.; Qin, W. P.

    2017-05-01

    Ho3+-doped AlF3-TeO2-based glass fibers based on AlF3-BaF2-CaF2-YF3-SrF2-MgF2-TeO2 glasses are fabricated by using a rod-in-tube method. The glass rod including a core and a thick cladding layer is prepared by using a suction method, where the thick cladding layer is used to protect the core from the effect of surface crystallization during the fiber drawing. By inserting the glass rod into a glass tube, the glass fibers with relatively low loss (~2.3 dB m-1 @ 1560 nm) are prepared. By using a 38 cm long Ho3+-doped AlF3-TeO2-based glass fiber as the gain medium and a 1965 nm fiber laser as the pump source, 2065 nm lasing is obtained for a threshold pump power of ~220 mW. With further increasing the pump power to ~325 mW, the unsaturated output power of the 2065 nm laser is about 82 mW and the corresponding slope efficiency is up to 68.8%. The effects of the gain fiber length on the lasing threshold, the slope efficiency, and the operating wavelength are also investigated. Our experimental results show that Ho3+-doped AlF3-TeO2-based glass fibers are promising gain media for 2.1 µm laser applications.

  3. Synthesis and physical properties of TEOS-based silica aerogels prepared by two step (acid-base) sol-gel process

    International Nuclear Information System (INIS)

    Venkateswara Rao, A.; Bhagat, S.D.

    2004-01-01

    The experimental results on the synthesis and physical properties of tetra-ethoxy-silane- (TEOS) based silica aerogels produced by two step (acid-base) sol-gel process, are reported. The oxalic acid (A) and NH 4 OH (B) concentrations were varied from 0 to 0.1 M and from 0.4 to 3 M, respectively. Monolithic and transparent aerogels have been obtained for the values of A=0.001 M and B=1 M. The effect of time interval (t) before the base catalyst (NH 4 OH) addition to the acidic sol was studied from 0 to 72 h. The time interval at t=24 h of NH 4 OH addition was found to be the best, in terms of low volume shrinkage, high optical transmission and monolithicity. The molar ratio of EtOH/TEOS (S) was varied from 3 to 7.5. Monolithic and transparent aerogels were obtained for an S value of 6.9. Also, the effects of molar ratio of acidic water, i.e., H 2 O/TEOS (W1) and basic water, i.e., H 2 O/TEOS (W2) on the physical properties of the aerogels have been studied. Highly transparent (about 90%) and monolithic aerogels with lower volume shrinkage ( 2 O):basic (H 2 O). The results are discussed by taking into consideration the hydrolysis and poly-condensation reactions. The aerogels were characterized by scanning electron microscopy (SEM), optical transmission, bulk density, volume shrinkage and porosity measurements. (authors)

  4. X-ray diffraction study on microstructure of Li20-TeO2 glasses; Xsen kaisetsuho ni yoru Li{sub 2}O-TeO{sub 2} kei garasu no mikuro kozo kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Iwadate, Y; Hattori, T; Nishiyama, S; Fukushima, K; Sugawara, Y [Chiba Univ. (Japan); Noda, K. [Japan Atomic Energy Research Inst., Tokyo (Japan)] Tatsumisuna, M. [Osaka Prefectural Univ., Sakai (Japan)] Umesaki, M. [Osaka Industrial Research Inst., Osaka (Japan)

    1998-07-10

    Li2O-TeO2 glasses attract attention because of unique properties such as high density, high refractive index, large dielectric constants and high infrared transmittance. The short range structures of two samples of Li2O-TeO2 glasses (15:85 mol% Li2O-TeO2 and 25:75 mol% Li2O-TeO2) were investigated by X-ray diffraction technique. Interpretation of the obtained radial distribution functions was performed on the basis of the strength comparison method. The following conclusions were obtained: Two types of Te-O bond lengths of 0.18nm and 0.20nm are found in TeO4 tetragonal bipyramid. As network forming units, the TeO4 tetragonal bipyramids and TeO3 trigonal bipyramids are observed. The TeO4 tetragonal bipyramid units are transformed into the TeO3 trigonal bipyramids through the transient species of polyhedral with non-bridging oxygen atoms with increasing content of Li2O. The lone pair of Te atom does not contribute to the formation of the glass network. 17 refs., 6 figs., 2 tabs.

  5. Spectroscopic and optical properties of the VO2+ ion doped TeO2-TiO2-ZnO-Nb2O5 glass system

    Science.gov (United States)

    Swapna; Upender, G.; Sreenivasulu, V.; Prasad, M.

    2016-04-01

    Studies such as optical absorption, Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, Electron paramagnetic resonance (EPR) spectroscopy and Differential scanning calorimetry (DSC) were carried out on VO2+ ion doped TeO2-TiO2-ZnO-Nb2O5 glass system. Raman and FTIR spectra of the glasses revealed the presence of [TeO3], [TeO4] and [NbO6] structural units in the glass network. The Urbach energy (Δ E), cut-off wavelength (λ c ), optical band gap ( E opt ), optical basicity (Λ) and electron polarizability ( α) of the glasses were determined from optical absorption studies. The density ( ρ), molar volume ( V m ), oxygen molar volume ( V o ) and refractive index ( n) were also measured. Spin-Hamiltonian parameters were calculated from the EPR studies. When Nb2O5 was increased at the expense of ZnO, the density, optical band gap and Urbach energy of the glasses increased, and the electronic polarizability and optical basicity decreased. The EPR spectra clearly showed that vanadium was in the glass as VO2+ and occupied octahedral sites with tetrahedral compression. Spin-Hamiltonian parameters g‖ and g⊥ decreased as Nb2O5 content increased in the glass. The glass transition temperature ( T g ) also increased with increasing Nb2O5 content in the glass.

  6. Temperature stable LiNbO3 surface acoustic wave device with diode sputtered amorphous TeO2 over-layer

    International Nuclear Information System (INIS)

    Dewan, Namrata; Tomar, Monika; Gupta, Vinay; Sreenivas, K.

    2005-01-01

    Amorphous TeO 2 thin film, sputtered in the O 2 +Ar(25%+75%) gas environment using a metallic tellurium target, has been identified as an attractive negative temperature coefficient of delay (TCD) material that can yield a temperature stable device when combined with a surface acoustic wave (SAW) device based on positive TCD material such as LiNbO 3 . The influence of amorphous TeO 2 over-layer on the SAW propagation characteristics (velocity and temperature coefficient of delay) of the SAW filters (36 and 70 MHz) based on 128 deg. rotated Y-cut X-propagating lithium niobate (128 deg. Y-X LiNbO 3 ) single crystal has been studied. It is found that 0.042 λ thick TeO 2 over-layer on a prefabricated SAW device operating at 36 MHz centre frequency, reduces the TCD of the device from 76 ppm deg. C -1 to almost zero (∼1.4 ppm deg. C -1 ) without deteriorating its efficiency and could be considered as a suitable alternative for temperature stable devices in comparison to conventional SiO 2 over-layer

  7. Thermal analyses, spectral characterization and structural interpretation of Nd3+/Er3+ ions co-doped TeO2-ZnCl2 glasses system

    Science.gov (United States)

    Ahmed, Kasim F.; Ibrahim, Saeed O.; Sahar, Md. R.; Mawlud, Saman Q.; Khizir, Hersh A.

    2017-09-01

    The Nd3+/Er3+ ions co-doped in the system of zinc-tellurite with the composition of (70-2x)TeO2-30ZnCl2-xNd2O3-xEr2O3 concentration from 1.0 to 3.0 mol% (x=1, 2 and 3) glasses were prepared by using conventional melt-quenching technique. The amorphous nature of the glass been confirmed by using X-RAY Diffraction Spectroscopy. Thermal characteristic were determined using a DTA. The obtained results discussed in terms of the glass structure. The glass structure studied by means of FTIR. Seven significant vibrational peaks around 471, 687, 742, 768, 1632, 2833 and 3378 cm-1 which correspond to the structural bonding of the glass are observed in a range of 400-4000cm-1. The peaks observed are consistent with the stretching and bending vibrations of the Te-O, TeO4 trigonal bipyramids, TeO3 trigonal pyramids, Te-O-Te and OH linkages respectively.

  8. The influence of TeO2 on thermal stability and 1.53 μm spectroscopic properties in Er(3+) doped oxyfluorite glasses.

    Science.gov (United States)

    Wang, Fengchao; Cai, Muzhi; Chen, Rong; Jing, Xufeng; Li, Bingpeng; Tian, Ying; Zhang, Junjie; Xu, Shiqing

    2015-11-05

    In this work, the thermal and spectroscopic properties of Er(3+)-doped oxyfluorite glass based on AMCSBYT (AlF3-MgF2-CaF2-SrF2-BaF2-YF3-TeO2) system for different TeO2 concentrations from 6 to 21 mol% is reported. After adding a suitable content of TeO2, the thermal ability of glass improves significantly whose ΔT and S can reach to 118 °C and 4.47, respectively. The stimulated emission cross-section reaches to 7.80×10(-21) cm(2) and the fluorescence lifetime is 12.18 ms. At the same time, the bandwidth characteristics reach to 46.41×10(-21) cm(2) nm and the gain performance is 63.73×10(-21) cm(2) ms. These results show that the optical performances of this oxyfluorite glass are very well. Hence, AMCSBYT glass with superior performances might be a useful material for applications in optical amplifier around 1.53 μm. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. The effects of Nd2O3 concentration in the laser emission of TeO2-ZnO glasses

    Science.gov (United States)

    Moreira, L. M.; Anjos, V.; Bell, M. J. V.; Ramos, C. A. R.; Kassab, L. R. P.; Doualan, D. J. L.; Camy, P.; Moncorgé, R.

    2016-08-01

    The present work reports the modification introduced by different Nd2O3 concentration on optical properties and the laser operation of Nd3+ doped (TeO2-ZnO) bulk tellurite glass. The spectroscopic data are analyzed within the Judd Ofelt formalism framework and the results are compared to the fluorescence lifetime and emission measurements to derive values for the quantum efficiency and the stimulated emission cross section of the considered 4F3/2 → 4I11/2 infrared laser transition around 1062.5 nm. Continuous-wave laser action is achieved with this bulk tellurite glass by pumping the sample inside a standard plan-concave mirror laser cavity with different output couplers. It is possible to observe coherent emission only for the lower concentration (0.5%(wt.) of Nd2 O3). Also laser action could only be observed for this sample with threshold pump power of 73 mW associated with a laser slope efficiency of 8% for an output coupler transmission of 4% indicating that TeO2-ZnO are potential materials for laser action. The results presented in this work together with those previously reported with higher concentration (1.0% (wt) of Nd2O3) determine the adequate Nd2O3 concentration for laser action and guide the correct experimental procedure for TeO2-ZnO glasses preparation.

  10. Observation of high-spin mixed oxidation state of cobalt in ceramic Co3TeO6

    Science.gov (United States)

    Singh, Harishchandra; Ghosh, Haranath; Chandrasekhar Rao, T. V.; Sinha, A. K.; Rajput, Parasmani

    2014-12-01

    We report coexistence of high spin Co3+ and Co2+ in ceramic Co3TeO6 using X-ray Absorption Near Edge Structure (XANES), DC magnetization, and first principles ab-initio calculations. The main absorption line of cobalt Co K-edge XANES spectra, along with a linear combination fit, led us to estimate relative concentration of Co2+ and Co3+as 60:40. The pre edge feature of XANES spectrum shows crystal field splitting of ˜1.26 eV between eg and t2g states, suggesting a mixture of high spin states of both Co2+ and Co3+. Temperature dependent high field DC magnetization measurements reveal dominant antiferromagnetic order with two Neel temperatures (TN1 ˜ 29 K and TN2 ˜ 18 K), consistent with single crystal study. A larger effective magnetic moment is observed in comparison to that reported for single crystal (which contains only Co2+), supports our inference that Co3+ exists in high spin state. Furthermore, we show that both Co2+ and Co3+ being in high spin states constitute a favorable ground state through first principles ab-initio calculations, where Rietveld refined synchrotron X-ray diffraction data are used as input.

  11. Optical Properties of Ternary TeO2-B2O3-ZnO Glass System

    Energy Technology Data Exchange (ETDEWEB)

    Ayuni, J N; Halimah, M K; Talib, Z A; Sidek, H A A; Daud, W M; Zaidan, A W; Khamirul, A M, E-mail: nfarhanayuni@gmail.com, E-mail: halimah@science.upm.edu.my [Department of Physics, Faculty of Science, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia)

    2011-02-15

    A series of ternary tellurite based glasses [(TeO2)70 (B203)30]100-x [ZnO]x glasses with different compositions of ZnO (x= 5 to 30 wt.% in steps of 5 wt.%) have been synthesized by melt quenching method. The role of ZnO to the glasses structure was studied by IR spectroscopy. FTIR spectra revealed broad, weak and strong absorption bands in the investigated range of wavenumber from 280-4000 cm-1 which associated with their corresponding bond modes of vibration and the glass structure. The indirect optical band gap and the direct optical band gap are in the range 2.08-3.12 and 1.54-2.36 eV, respectively. A decrease in the values of energy band gap Eg may come down to the reason that the non-bridging oxygen ion content increases with increasing ZnO content and shifting the band edge to lower energies. The optical band gap and Urbach energies were calculated from the absorption spectra measured between 190 and 900 nm at room temperature. The refractive index, n of the glasses change from 1.84-2.00 while the molar refractivities decrease from 13.06 to 12.00 with the increase of ZnO in mol%.

  12. Optical properties of ternary TeO2-B2O3-ZnO Glass system

    International Nuclear Information System (INIS)

    Nurfarhana Ayuni Joha; Halimah, M.K.; Talib, Z.A.; Sidek, H.A.A.; Daud, W.M.; Zaidan, A.W.; Khamirul, A.M.

    2009-01-01

    Full text: A series of ternary tellurite based glasses [ (TeO 2 ) 70 (B 2 0 3 ) 30 ] 100-x [ZnO] x glasses with different compositions of ZnO (x= 5 to 30 wt.% in steps of 5 wt.%) have been synthesized by melt quenching method. The role of ZnO to the glasses structure was studied by IR spectroscopy. FTIR spectra revealed broad, weak and strong absorption bands in the investigated range of wavenumber from 280 - 4000 cm -1 which associated with their corresponding bond modes of vibration and the glass structure. The indirect optical band gap and the direct optical band gap are in the range 2.08-3.12 and 1.54-2.36 eV, respectively. An increase in the values of energy band gap E g may come down to the reason that the non-bridging oxygen ion content decreases with increasing ZnO content and shifting the band edge to higher energies. The optical band gap and Urbach energies were calculated from the absorption spectra measured between 190 and 900 nm at room temperature. The refractive index, n of the glasses change from 1.84 - 2.00 while the molar refractivities decrease from 13.06 to 12.00 with the increase of ZnO in mol %. (author)

  13. Optical Properties of Ternary TeO2-B2O3-ZnO Glass System

    International Nuclear Information System (INIS)

    Ayuni, J N; Halimah, M K; Talib, Z A; Sidek, H A A; Daud, W M; Zaidan, A W; Khamirul, A M

    2011-01-01

    A series of ternary tellurite based glasses [(TeO2)70 (B203)30]100-x [ZnO]x glasses with different compositions of ZnO (x= 5 to 30 wt.% in steps of 5 wt.%) have been synthesized by melt quenching method. The role of ZnO to the glasses structure was studied by IR spectroscopy. FTIR spectra revealed broad, weak and strong absorption bands in the investigated range of wavenumber from 280-4000 cm-1 which associated with their corresponding bond modes of vibration and the glass structure. The indirect optical band gap and the direct optical band gap are in the range 2.08-3.12 and 1.54-2.36 eV, respectively. A decrease in the values of energy band gap Eg may come down to the reason that the non-bridging oxygen ion content increases with increasing ZnO content and shifting the band edge to lower energies. The optical band gap and Urbach energies were calculated from the absorption spectra measured between 190 and 900 nm at room temperature. The refractive index, n of the glasses change from 1.84-2.00 while the molar refractivities decrease from 13.06 to 12.00 with the increase of ZnO in mol%.

  14. Low temperature deposition: Properties of SiO{sub 2} films from TEOS and ozone by APCVD system

    Energy Technology Data Exchange (ETDEWEB)

    Juarez, H; Diaz, T; Rosendo, E; Garcia, G; Mora, F; Escalante, G [Centro de Investigacion en Dispositivos Semiconductores, Universidad Autonoma de Puebla, 14 Sur and Av. San Claudio, San Manuel 72000, Puebla (Mexico); Pacio, M; GarcIa, A, E-mail: hjuarez@cs.buap.m [Ingenieria Electrica, Secciaan Electranica del Estado Salido, Centro de Investigacian y de Estudios Avanzados del I. P. N., Av. Instituto Politecnico Nacional 2508, San Pedro Zacatenco, 07360 Mexico, D. F. (Mexico)

    2009-05-01

    An Atmospheric Pressure Chemical Vapor Deposition (APCVD) system was implemented for SiO{sub 2} nanometric films deposition on silicon substrates. Tetraethoxysilane (TEOS) and ozone (O{sub 3}) were used and they were mixed into the APCVD system. The deposition temperatures were very low, from 125 to 250 {sup 0}C and the deposition time ranged from 1 to 15 minutes. The measured thicknesses from the deposited SiO{sub 2} films were between 5 and 300 nm. From the by Fourier-Transform Infrared (FTIR) spectra the typical absorption bands of the Si-O bond were observed and it was also observed a dependence on the vibrational modes corresponding to hydroxyl groups with the deposition temperature where the intensity of these vibrations can be related with the grade porosity grade of the films. Furthermore an analytical model has been evoked to determine the activation energy of the reactions in the surface and the gas phase in the deposit films process.

  15. Degradation of TCE by TEOS Coated nZVI in the Presence of Cu(II) for Groundwater Remediation

    International Nuclear Information System (INIS)

    Ramamurthy, A.S.; Eglal, M.M.

    2014-01-01

    The removal of TCE by nanofer zero valent iron (nanofer ZVI) coated with tetraethyl orthosilicate (TEOS) in the presence of Cu(II) at different environmental conditions was studied. The kinetics of TCE degradation by nanofer ZVI was determined. At a dosage of 10 mg of nanofer ZVI, almost 63% of TCE was removed, when Cu(II) and TCE were present. It contrasts with 42% degradation of TCE in the absence of Cu(II). SEM/EDS images indicated that Cu(II) is reduced to form Cu 0 and Cu 2 O. These formations are considered to be responsible for enhancing TCE degradation. Direct reduction involves hydrogenolysis and β-elimination in the transformation of TCE, while indirect reduction involves atomic hydrogen and no direct electron transfer from the metal to reactants. The reduction of activation energy was also noted indicating that the rate limiting step for TCE degradation in the presence of Cu(II) is surface chemical reaction rather than diffusion. Most of iron present in nanofer ZVI get dissolved causing the generation of localized positive charge regions and form metal chlorides. Local accumulation of hydrochloric acid inside the pits regenerates new reactive surfaces to serve as sources of continuous electron generation. No significant effect of TCE was noticed for Cu(II) sequestration.

  16. Impact of the new equation of state of seawater (TEOS-10) on the estimates of water mass mixture and meridional transport in the Atlantic Ocean

    Science.gov (United States)

    Almeida, Lucas; de Azevedo, José Luiz Lima; Kerr, Rodrigo; Araujo, Moacyr; Mata, Mauricio M.

    2018-03-01

    The equation of state of seawater (EOS) provides a simple way to link the properties of seawater that are the most important for ocean dynamics and the ocean-atmosphere climate system. In 2010, the set of equations used to derive all thermodynamic properties of seawater were updated using a thermodynamic approach. The new approach, named TEOS-10, results in better estimates of seawater properties, such as salinity and temperature, when compared to the previous EOS version (EOS-80). Since several physical processes in the oceans are driven by these properties, improvements in the EOS performance are expected to lead to a better and more realistic representation of the ocean. This work focuses on assessing the main differences of the: (i) contribution of water masses to a total mixture, (ii) baroclinic velocity, and (iii) volume and heat transport, as calculated by the EOS-80 and by the TEOS-10, along four zonal transects at 26.5°N, 10°N, 11°S, and 34.5°S in the Atlantic Ocean. The density differences (always between TEOS-10 and EOS-80) increase with depth and hence the results indicate that the most significant difference in the water mass contributions was found for Antarctic Bottom Water. Within that layer, the differences reach up to 10% on its fraction of the mixture when calculated by the TEOS-10, although the difference in the North Atlantic Deep Water contribution was not negligible either. The estimated baroclinic velocities showed considerable differences in all studied areas, being more significant over boundary current systems. The Gulf Stream presented lower velocity, while the Brazil Current presented increasing velocity when using TEOS-10. The comparison between values computed for volume transported by the Atlantic Meridional Overturning Circulation showed a total difference of about +6%, which cannot be neglected when considering the space and time variability involved. The heat transport showed significant differences in the study areas at the

  17. Effects of Sm3+/Yb3+ co-doping and temperature on the Raman, IR spectra and structure of [TeO2-GeO2-K2O-Sm2O3/Yb2O3] glasses

    International Nuclear Information System (INIS)

    Shaltout, I.; Badr, Y.

    2006-01-01

    Effects of Sm 3+ /Yb 3+ co-doping on Raman scattering, IR absorption, temperature dependence of the Raman spectra up to 210 o C and the structure of two glass systems of the composition (80TeO 2 -10GeO 2 -8K 2 O-2Sm 2 O 3 /Yb 2 O 3 ) is discussed. It was found that the addition of Yb 3+ to the glass very strongly enhances the intensities of the antistokes' Raman bands at 155, 375, 557 and 828 cm -1 and quenches both the intensities of the stokes' vibration modes of the TeO 4 units in the range of 120-770 cm -1 and the intensities of the OH - stretching vibration modes in the range of 2600-3300 cm -1 . Sm 2 O 3 /Yb 2 O 3 rare earth co-doping has a great influence on removing and/or changing the nature of the OH - groups. The appearance and splitting of the stretching vibration modes of the OH - groups at lower frequencies (2770, 2970 cm -1 ) for the Sm +3 singly doped glass sample, compared to the band at ∼3200 cm -1 for the Sm 3+ /Yb 3+ co-doped glass sample, suggested that the OH - groups are more strongly bonded and incorporated with the glass matrix for the singly doped glass. Heating the sample up continuously weakens the hydrogen bonding of the OH - groups to the glass matrix leading to creation of NBO and breakdown of the connectivity of the OH - groups to the TeO 4 , TeO 3+1 and TeO 3 structural units. Raman bands at 286, 477, 666 and 769 cm -1 were assigned to its respective vibrations of Te 2 O 7 , TeO 4 -4 species, the (Te-O-Te) bending vibrations of the TeO 4 triagonal bipyramids (tbps), the axial symmetric stretching vibration modes (Te ax -O) s with bridging oxygen BO atoms and to the (Te-O) nbo non-bridging stretching vibration modes of the TeO 3+1 and/or TeO 3 pyramids

  18. Absolute Salinity, ''Density Salinity'' and the Reference-Composition Salinity Scale: present and future use in the seawater standard TEOS-10

    Directory of Open Access Journals (Sweden)

    D. G. Wright

    2011-01-01

    Full Text Available Salinity plays a key role in the determination of the thermodynamic properties of seawater and the new TEOS-101 standard provides a consistent and effective approach to dealing with relationships between salinity and these thermodynamic properties. However, there are a number of practical issues that arise in the application of TEOS-10, both in terms of accuracy and scope, including its use in the reduction of field data and in numerical models.

    First, in the TEOS-10 formulation for IAPSO Standard Seawater, the Gibbs function takes the Reference Salinity as its salinity argument, denoted SR, which provides a measure of the mass fraction of dissolved material in solution based on the Reference Composition approximation for Standard Seawater. We discuss uncertainties in both the Reference Composition and the Reference-Composition Salinity Scale on which Reference Salinity is reported. The Reference Composition provides a much-needed fixed benchmark but modified reference states will inevitably be required to improve the representation of Standard Seawater for some studies. However, the Reference-Composition Salinity Scale should remain unaltered to provide a stable representation of salinity for use with the TEOS-10 Gibbs function and in climate change detection studies.

    Second, when composition anomalies are present in seawater, no single salinity variable can fully represent the influence of dissolved material on the thermodynamic properties of seawater. We consider three distinct representations of salinity that have been used in previous studies and discuss the connections and distinctions between them. One of these variables provides the most accurate representation of density possible as well as improvements over Reference Salinity for the determination of other thermodynamic properties. It is referred to as "Density Salinity" and is represented by the symbol

  19. Absolute Salinity, ''Density Salinity'' and the Reference-Composition Salinity Scale: present and future use in the seawater standard TEOS-10

    Science.gov (United States)

    Wright, D. G.; Pawlowicz, R.; McDougall, T. J.; Feistel, R.; Marion, G. M.

    2011-01-01

    Salinity plays a key role in the determination of the thermodynamic properties of seawater and the new TEOS-101 standard provides a consistent and effective approach to dealing with relationships between salinity and these thermodynamic properties. However, there are a number of practical issues that arise in the application of TEOS-10, both in terms of accuracy and scope, including its use in the reduction of field data and in numerical models. First, in the TEOS-10 formulation for IAPSO Standard Seawater, the Gibbs function takes the Reference Salinity as its salinity argument, denoted SR, which provides a measure of the mass fraction of dissolved material in solution based on the Reference Composition approximation for Standard Seawater. We discuss uncertainties in both the Reference Composition and the Reference-Composition Salinity Scale on which Reference Salinity is reported. The Reference Composition provides a much-needed fixed benchmark but modified reference states will inevitably be required to improve the representation of Standard Seawater for some studies. However, the Reference-Composition Salinity Scale should remain unaltered to provide a stable representation of salinity for use with the TEOS-10 Gibbs function and in climate change detection studies. Second, when composition anomalies are present in seawater, no single salinity variable can fully represent the influence of dissolved material on the thermodynamic properties of seawater. We consider three distinct representations of salinity that have been used in previous studies and discuss the connections and distinctions between them. One of these variables provides the most accurate representation of density possible as well as improvements over Reference Salinity for the determination of other thermodynamic properties. It is referred to as "Density Salinity" and is represented by the symbol SAdens; it stands out as the most appropriate representation of salinity for use in dynamical physical

  20. Absolute Salinity, "Density Salinity" and the Reference-Composition Salinity Scale: present and future use in the seawater standard TEOS-10

    Science.gov (United States)

    Wright, D. G.; Pawlowicz, R.; McDougall, T. J.; Feistel, R.; Marion, G. M.

    2010-08-01

    Salinity plays a key role in the determination of the thermodynamic properties of seawater and the new TEOS-101 standard provides a consistent and effective approach to dealing with relationships between salinity and these thermodynamic properties. However, there are a number of practical issues that arise in the application of TEOS-10, both in terms of accuracy and scope, including its use in the reduction of field data and in numerical models. First, in the TEOS-10 formulation for IAPSO Standard Seawater, the Gibbs function takes the Reference Salinity as its salinity argument, denoted SR, which provides a measure of the mass fraction of dissolved material in solution based on the Reference Composition approximation for Standard Seawater. We discuss uncertainties in both the Reference Composition and the Reference-Composition Salinity Scale on which Reference Salinity is reported. The Reference Composition provides a much-needed fixed benchmark but modified reference states will inevitably be required to improve the representation of Standard Seawater for some studies. The Reference-Composition Salinity Scale should remain unaltered to provide a stable representation of salinity for use with the TEOS-10 Gibbs function and in climate change detection studies. Second, when composition anomalies are present in seawater, no single salinity variable can fully represent the influence of dissolved material on the thermodynamic properties of seawater. We consider three distinct representations of salinity that have been used in previous studies and discuss the connections and distinctions between them. One of these variables provides the most accurate representation of density possible as well as improvements over Reference Salinity for the determination of other thermodynamic properties. It is referred to as "Density Salinity" and is represented by the symbol SAdens; it stands out as the most appropriate representation of salinity for use in dynamical physical

  1. Ethyl group as matrix modifier and inducer of ordered domains in hybrid xerogels synthesised in acidic media using ethyltriethoxysilane (ETEOS) and tetraethoxysilane (TEOS) as precursors

    International Nuclear Information System (INIS)

    Rios, Xabier; Moriones, Paula; Echeverría, Jesús C.; Luquin, Asunción; Laguna, Mariano; Garrido, Julián J.

    2013-01-01

    Hybrid silica xerogels favourably combine the properties of organic and inorganic components in one material; consequently these materials are useful for multiple applications. The versatility and mild synthetic conditions provided by the sol-gel process are ideal for the synthesis of hybrid materials. The specific aims of this study were to synthesise hybrid xerogels in acidic media using tetraethoxysilane (TEOS) and ethyltriethoxysilane (ETEOS) as silica precursors, and to assess the role of the ethyl group as a matrix modifier and inducer of ordered domains in xerogels. All xerogels were synthesised at pH 4.5, at 60 °C, with 1:4.75:5.5 TEOS:EtOH:H 2 O molar ratio. Gelation time exponentially increased with the ETEOS molar ratio. Incorporation of the ethyl groups into the structure of xerogels reduced cross-linking, increased the average siloxane bond length, and promoted the formation of ordered domains. As a result, a transition from Q n to T n signals detected in the 29 Si NMR spectra, the Si–O structural band in the FTIR spectra shifted to lower wavelength, and a new peak in the XRD pattern at 2θ < 10° appeared in the XRD patterns. Mass spectroscopy detected fragments with high numbers of silicon atoms and a polymeric distribution. - Graphical abstract: Display Omitted - Highlights: • Hybrid xerogels were synthesised for ETEOS/TEOS mixtures up to 80% ETEOS. • The gelification time exponentially increased with ETEOS content. • FTIR, XRD and MAS NMR demonstrated the presence of ethyl groups into xerogels. • For ETEOS contents ≤30%, ethyl group acted as matrix modifier. • For ETEOS contents ≥30%, ethyl groups induced the formation of ordered domains

  2. A Study on Anti – Fouling Behaviour and Mechanical Properties of PVA/Chitosan/TEOS Hybrid membrane in The Treatment of Copper Solution

    Science.gov (United States)

    Sulaiman, N. A.; Kassim Shaari, N. Z.; Rahman, N. Abdul

    2018-05-01

    In a wastewater treatment by using membrane filtration, fouling has been one of the major problems. In this study, the anti-fouling behaviour of the fabricated thin-film composite membrane were studied during the treatment of water containing copper ion. The membranes were prepared from a polymer blend of 2wt.% chitosan with 10 wt.% poly(vinyl alcohol) (PVA) and then it was cross – linked with tetraethylorthosilicate (TEOS) through sol-gel method. The membrane had been evaluated for its resistance against organic fouling where humic acid had been chosen as organic foulant model which represent the natural organic matter (NOM) in water or wastewater. The dead-end filtration experiments were carried out by using 50 ppm of copper solution with and without the presence of humic acid as feed solution, which was passed through two types of thin film composite membranes. The possible reversible fouling was evaluated by using relative flux decay (RFD) and relative flux recovery (RFR) calculations. The percentage of copper ion removal was evaluated by using Atomic Absorption Spectroscopy (AAS). Based on the results, with the presence of humic acid, the membrane incorporated with silica precursor (TEOS) showed lower flux decay (3%) and higher flux recovery (76%), which show that the formulated hybrid membrane possesses the anti fouling property. The same trend was observed in the mechanical properties of hybrid membrane, where the presence of TEOS has improved the tensile strength and flexibility of the membrane. Therefore, the fabricated thin film composite with the anti-fouling properties and good physical flexibility has potential to be used in the treatment of wastewater containing heavy metal as it could result in good saving in term of operational cost.

  3. Heat Treatment Effect on Eu3+ Doped TeO2-BaO-Bi2O3 Glass Systems with Ag Nanoparticles

    Directory of Open Access Journals (Sweden)

    Tomasz Lewandowski

    2017-01-01

    Full Text Available Glass systems of 73TeO2-4BaO-3Bi2O3-2Eu2O3-xAg (in molar ratio where x = 0, 1, 2, and 3 compositions have been successfully synthesized. Silver nanoparticles were obtained with the employment of heat treatment (HT procedure executed at 350°C. Glass transition temperatures of different compositions have been determined through DSC measurements. XRD results presented characteristic amorphous halo indicating lack of long range order in the samples. FTIR structural studies revealed that glass matrix is mainly composed of TeO3 and TeO4 species and is stable after different applied heat treatment times. X-ray photoelectron spectroscopy (XPS measurements confirmed that in selected samples part of Ag ions changed oxidation state to form Ag0 species. TEM measurements revealed nanoparticles of size in the range of 20–40 nm. UV-vis absorption results demonstrated characteristic transitions of Eu3+ ions. Additionally, UV-vis spectra of samples heat-treated for 6, 12, 24, and 48 hours presented bands related to silver nanoparticles. Photoluminescence (PL studies have been performed with excitation wavelength of λexc=395 nm. Obtained spectra exhibited peaks due to 5D0-7FJ (where J=2,3,4 and 5D1-7FJ (where J=1,2,3 transitions of Eu3+. Moreover, luminescence measurement indicated enhancement of rare earth ions emissions in several of the annealed samples. Increase of emission intensity of about 35% has been observed.

  4. Influence of composition and preparation conditions on some physical properties of TeO2–Sb2O3–PbCl2 glasses

    Czech Academy of Sciences Publication Activity Database

    Bošák, O.; Kostka, Petr; Minárik, S.; Trnovcová, V.; Podolinčiaková, J.; Zavadil, Jiří

    2013-01-01

    Roč. 377, spec. is. (2013), s. 74-78 ISSN 0022-3093. [International Symposium on Non-Oxide and New Optical Glasses /18./ - ISNOG 2012. Saint-Malo, 01.07.2012-05.07.2012] R&D Projects: GA ČR GAP106/12/2384; GA MŠk 7AMB12SK147 Institutional support: RVO:67985891 ; RVO:67985882 Keywords : heavy metal oxychloride glasses * TeO2 * electrical conductivity * static permittivity Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass; JA - Electronics ; Optoelectronics, Electrical Engineering (URE-Y) Impact factor: 1.716, year: 2013

  5. Resolved discrepancies between visible spontaneous Raman cross-section and direct near-infrared Raman gain measurements in TeO2-based glasses.

    Science.gov (United States)

    Rivero, Clara; Stegeman, Robert; Couzi, Michel; Talaga, David; Cardinal, Thierry; Richardson, Kathleen; Stegeman, George

    2005-06-13

    Disagreements on the Raman gain response of different tellurite-based glasses, measured at different wavelengths, have been recently reported in the literature. In order to resolve this controversy, a multi-wavelength Raman cross-section experiment was conducted on two different TeO2-based glass samples. The estimated Raman gain response of the material shows good agreement with the directly-measured Raman gain data at 1064 nm, after correction for the dispersion and wavelength-dependence of the Raman gain process.

  6. Appraisal of the correspondence of the safety improvement measures proposed for the Mochovce NPP with respect to the ones outlined in the TEO for the Juragua NPP

    International Nuclear Information System (INIS)

    Pereira Hernandez, Guillermo

    1996-01-01

    The work accomplished consisted in determining the correspondence or relationship between the safety improvement measures of the outlined for both plants as well as a preliminary analysis from which were determined. The measures which a deeper analysis is recommended to evaluate theirs possible addition to the group it is recommended to deepen with a view to take into considerations aspects of interest that in them are outlined and which could serve to enhance the approach or the linkage of the measures outlined in the TEO

  7. Cs_7Sm_1_1[TeO_3]_1_2Cl_1_6 and Rb_7Nd_1_1[TeO_3]_1_2Br_1_6, the new tellurite halides of the tetragonal Rb_6LiNd_1_1[SeO_3]_1_2Cl_1_6 structure type

    International Nuclear Information System (INIS)

    Charkin, Dmitri O.; Black, Cameron; Downie, Lewis J.; Sklovsky, Dmitry E.; Berdonosov, Peter S.; Olenev, Andrei V.; Zhou, Wuzong; Lightfoot, Philip; Dolgikh, Valery A.

    2015-01-01

    Two new rare-earth – alkali – tellurium oxide halides were synthesized by a salt flux technique and characterized by single-crystal X-ray diffraction. The structures of the new compounds Cs_7Sm_1_1[TeO_3]_1_2Cl_1_6 (I) and Rb_7Nd_1_1[TeO_3]_1_2Br_1_6 (II) (both tetragonal, space group I4/mcm) correspond to the sequence of [MLn_1_1(TeO_3)_1_2] and [M_6X_1_6] layers and bear very strong similarities to those of known selenite analogs. We discuss the trends in similarities and differences in compositions and structural details between the Se and Te compounds; more members of the family are predicted. - Graphical abstract: Two new rare-earth – alkali – tellurium oxide halides were predicted and synthesized. - Highlights: • Two new rare-earth – alkali – tellurium oxide halides were synthesized. • They adopt slab structure of rare earth-tellurium-oxygen and CsCl-like slabs. • The Br-based CsCl-like slabs have been observed first in this layered family.

  8. Effects of Tetraethyl Orthosilicate (TEOS on the Light and Temperature Stability of a Pigment from Beta vulgaris and Its Potential Food Industry Applications

    Directory of Open Access Journals (Sweden)

    Gustavo A. Molina

    2014-11-01

    Full Text Available A novel, simple and inexpensive modification method using TEOS to increase the UV light, pH and temperature stability of a red-beet-pigment extracted from Beta vulgaris has been proposed. The effects on the molecular structure of betalains were studied by FTIR spectroscopy. The presence of betacyanin was verified by UV-Vis spectroscopy and its degradation in modified red-beet-pigment was evaluated and compared to the unmodified red-beet-pigment; performance improvements of 88.33%, 16.84% and 20.90% for UV light, pH and temperature stability were obtained, respectively,. Measurements of reducing sugars, phenol, and antioxidant contents were performed on unmodified and modified red-beet-pigment and losses of close to 21%, 54% and 36%, respectively, were found to be caused by the addition of TEOS. Polar diagrams of color by unmodified and modified red-beet-pigment in models of a beverage and of a yogurt were obtained and the color is preserved, although here is a small loss in the chromaticity parameter of the modified red-beet-pigment.

  9. Synthesis, structural, thermal and optical properties of TeO2-Bi2O3-GeO2-Li2O glasses

    Science.gov (United States)

    Dimowa, Louiza; Piroeva, Iskra; Atanasova-Vladimirova, S.; Petrova, Nadia; Ganev, Valentin; Titorenkova, Rositsa; Yankov, Georgi; Petrov, Todor; Shivachev, Boris L.

    2016-10-01

    In this study, synthesis and characterization of novel quaternary tellurite glass system TeO2-Bi2O3-GeO2-Li2O is presented. The compositions include TeO2 and GeO2 as glass formers while different proportion of Bi2O3 and Li2O act as network modifiers. Differential thermal analysis, X-ray diffraction, scanning electron microscopy energy dispersive X-ray spectroscopy, laser ablation inductively coupled plasma mass spectrometry, UV-Vis and Raman spectroscopy are applied to study the structural, thermal and optical properties of the studied glasses. Obtained glasses possess a relatively low glass transition temperature (around 300 °C) if compared to other tellurite glasses, show good thermal transparency in the visible and near infra-red (from 2.4 to 0.4 μm) and can double the frequency of laser light from its original wavelength of 1064 nm to its second-harmonic at 532 nm (i.e. second harmonic generation).

  10. Two-Phase Diffusion Technique for the Preparation of Ultramacroporous/Mesoporous Silica Microspheres via Interface Hydrolysis, Diffusion, and Gelation of TEOS.

    Science.gov (United States)

    Ju, Minhua; Li, Yupeng; Yu, Liang; Wang, Chongqing; Zhang, Lixiong

    2018-02-06

    Honeycombed hierarchical ultramacroporous/mesoporous silica microspheres were prepared via the hydrolysis of TEOS in the oil-water interface, with subsequent diffusion and gelation in the acidic water-phase microdroplets with the assistance of a simple homemade microdevice. The diffusion of furfuryl alcohol (FA) also happened at a relatively high rate during the hydrolysis and diffusion of TEOS. Therefore, plenty of FA will be inside of the water microdroplets and form a decent number of polyfurfuryl alcohol (PFA) microparticles, thereby obtaining honeycombed hierarchical porosity silica microspheres with abundant ultramacroporous cavities and mesopores after calcination. It was found that the concentration of FA, residence time, and reaction temperature have significant effects on the porosity and pore size due to the influence on the diffusion rate and amount of FA in water-phase microdroplets. The honeycombed silica microspheres have obvious microscopic visible ultramacroporous cavities with the submicrometer cavity diameter as high as 85% porosity based on the rough overall volume of microsphere. N 2 adsorption-desorption isotherms show that the honeycombed hierarchical porosity silica microspheres have a high surface area of 602 m 2 g -1 , a mesopore volume of 0.77 cm 3 /g, and a mesopore porosity of 99.6% based on the total pore volume of N 2 adsorption-desorption. On the basis of the experiment results, a rational formation process of the honeycombed hierarchical porosity silica microspheres was deduced.

  11. Seguimiento por espectroscopia infrarroja (FT-IR de la copolimerización de TEOS (tetraetilortosilicato y PDMS (polidimetilsiloxano en presencia de tbt (tetrabutiltitanio

    Directory of Open Access Journals (Sweden)

    Téllez, L.

    2004-10-01

    Full Text Available Hybrid materials have been prepared in this work through the reactions of Si and Ti alkoxides (TEOS and TBT, respectively and polydimethil siloxane (PDMS. These reactions have been studied by means of FT-IR spectroscopy during the whole reaction time. The hydrolysis of TEOS molecule has been followed by the 880 cm-1 band, and the self-condensation reactions through the 1180 and 1150 cm-1 bands. Polycondesation reaction between Si-OH groups and PDMS molecules has been followed by the 850 cm-1 band. On the other hand, the hydrolysis reaction of TBT and the self-condensation of Ti-OH groups have been followed by the 1130 and 770-510 cm-1 bands, respectively. Finally the condensation reaction between Si-OH and Ti-OH groups have been studied by the 936 cm-1 band. Results have shown that hydrolysis and condensation reactions are depending on TBT concentration. The formation of Si-O-Si cross-linked structures increases with the TBT concentrations in the reaction. The selfcondensation reaction of Si-OH grups or Ti-OH grous is very reapid forming Si-O-Si and Ti-O-Ti bonds, respectively. However, the Si-O-Ti bonds which are formed during the first moments of reaction are also rapidly broken due to H2O molecules or the reaction medium. The evolution of PDMS linear and cyclic molecules is also studied.

    Se han preparado materiales híbridos por medio de reacciones de hidrólisis y condensación de alcóxidos de Si y Ti (TEOS y TBT, respectivamente y de reacciones de copolimerización de éstos con polidimetilsiloxano (PDMS. Se han estudiado las citadas reacciones mediante espectroscopia FT-IR, desde el mismo comienzo hasta la obtención del material final. La hidrólisis del TEOS así como la autocondensación del os grupos Si-OH generados tanto para formar cadenas entrecruzadas como lineales se han seguido mediante las bandas situadas a 880, 1180 y 1150 cm-1, respectivamente. La policondensación de dichos grupos con PDMS se ha seguido por la banda a

  12. Índices de confiabilidade da análise do ângulo poplíteo através da biofotogrametria

    Directory of Open Access Journals (Sweden)

    Ricardo B. Duarte

    2014-12-01

    Full Text Available Introdução: A avaliação e a mensuração objetiva da amplitude articular são de fundamental importância para o diagnóstico, planejamento e acompanhamento de um tratamento. Com o avanço da tecnologia, a biofotogrametria começa a ser utilizada com maior frequência no meio fisioterapêutico, mensurando a quantidade de movimento articular. O ângulo poplíteo foi escolhido por ser uma medida indireta da flexibilidade da musculatura ísquiossural. A retração dos isquiossurais pode resultar em problemas posturais significativos e produzir uma inclinação posterior contínua da pelve, afetando a marcha e o gesto esportivo, sendo também uma das causas de dores musculares ou articulares. Objetivos: Verificar as confiabilidades intra e inter-examinador da análise de ângulo poplíteo através a fotogrametria computadorizada, utilizando o software para avaliação postural (SAPo, buscando estabelecer a repetibilidade e a reprodutibilidade do método. Métodos: Foram avaliados 23 indivíduos (46 joelhos. Os voluntários foram posicionados em decúbito dorsal, com quadril e joelho do membro inferior avaliado fletidos a 90 graus, mantendo o membro contralateral em extensão. A seguir, o joelho do membro testado era estendido passivamente, até o ponto no qual se percebia primeira resistência dos músculos ao alongamento. Neste ponto, foi feito o registro do ângulo poplíteo. A análise estatística da confiabilidade inter e intra-examinador foi averiguada pelos resultados do coeficiente de correlação intra-classe (ICC dos tipos 1,1 e 3,1 no teste de correlação de Pearson, considerando um nível de significância de p<0,05. Resultados: O método de avaliação do ângulo poplíteo pela biofotogrametria apresentou confiabilidade forte (ICC = 0,786 intra-examinador e confiabilidade muito forte (ICC = 0,920 inter-examinador. Conclusão: A biofotogrametria é um método apropriado para a avaliação do ângulo poplíteo uma vez que os valores

  13. Ba 3 (Cr 0.97(1) Te 0.03(1) ) 2 TeO 9 : in Search of Jahn–Teller Distorted Cr(II) Oxide

    Energy Technology Data Exchange (ETDEWEB)

    Li, Man-Rong; Deng, Zheng; Lapidus, Saul H.; Stephens, Peter W.; Segre, Carlo U.; Croft, Mark; Paria Sena, Robert; Hadermann, Joke; Walker, David; Greenblatt, Martha

    2016-10-17

    A novel 6H - type hexagonal perovskite Ba 3 (Cr 0.97(1) Te 0.03 (1 ) ) 2 TeO 9 was prepared at high pressure (6 GPa) and temperature ( 1 773 K). Both transmission electron microscopy and synchrotron powder x - ray diffraction data demonstrate that Ba 3 (Cr 0.97(1) Te 0.03(1) ) 2 TeO 9 crystallize s in P6 3 / mmc with face - shared (Cr 0.97(1) Te 0.03(1) )O 6 octahedral pairs interconnected with TeO 6 octahedra via corner - sharing. Structure analysis shows a mixed Cr 2+ /Cr 3+ valence state with ~ 10% Cr 2+ . The existence of Cr 2+ in Ba 3 (Cr 2+ 0.10(1) Cr 3+ 0.87(1) Te 6+ 0.03 ) 2 TeO 9 is further evidenced by x - ray absorption near edge spectr oscopy . Magnetic properties measurements show a paramagnetic response down to 4 K and a small glassy - state curvature at low temperature. In this work, the o ctahedral Cr 2+ O 6 component is stabilized in an oxide material for the first time ; the expected Jahn - Teller distortion of high - spin ( d 4 ) Cr 2+ is not found , which is attributed to the small proportion of Cr 2+ (~ 10%) and the face - sharing arrangement of CrO 6 octahedral pairs, that structu rally dis favor axial distortion.

  14. Intense upconversion luminescence and effect of local environment for Tm3+/Yb3+ co-doped novel TeO2-BiCl3 glass system.

    Science.gov (United States)

    Wang, Guonian; Dai, Shixun; Zhang, Junjie; Wen, Lei; Yang, Jianhu; Jiang, Zhonghong

    2006-05-15

    We present the results of a study that uses theoretical and experimental methods to investigate the characteristics of the upconversion luminescence of Tm3+/Yb3+ codoped TeO2-BiCl3 glass system as a function of the BiCl3 fraction. These glasses are potentially important in the design of upconversion fiber lasers. Effect of local environment around Tm3+ on upconversion fluorescence intensity was analyzed by theoretical calculations. The structure and spectroscopic properties were investigated in the experiments by measuring the Raman spectra, IR transmission spectra, and absorption and fluorescence intensities at room temperature. The results indicate that blue luminescence quantum efficiency increases with increasing BiCl3 content from 10 to 60 mol%, which were interpreted by the increase of asymmetry of glass structure, decrease of phonon energy and removing of OH- groups.

  15. Study of broadband near-infrared emission in Tm3+-Er3+ codoped TeO2-WO3-PbO glasses.

    Science.gov (United States)

    Balda, R; Fernández, J; Fernández-Navarro, J M

    2009-05-25

    In this work, we report the near-infrared emission properties of Tm(3+)-Er(3+) codoped tellurite TeO(2)-WO(3)-PbO glasses under 794 nm excitation. A broad emission from 1350 to 1750 nm corresponding to the Tm(3+) and Er(3+) emissions is observed. The full width at half-maximum of this broadband increases with increasing [Tm]/[Er] concentration ratio up to a value of ~ 160 nm. The energy transfer between Tm(3+) and Er(3+) ions is evidenced by both the temporal behavior of the near-infrared luminescence and the effect of Tm3+ codoping on the visible upconversion of Er(3+) ions.

  16. 1887 nm lasing in Tm3+-doped TeO2-BaF2-Y2O3 glass microstructured fibers

    Science.gov (United States)

    Wang, Shunbin; Yao, Chuanfei; Jia, Zhixu; Qin, Guanshi; Qin, Weiping

    2017-04-01

    In this paper, we demonstrate ∼2 μm lasing in Tm3+-doped fluorotellurite microstructured fibers. The Tm3+-doped fibers are based on TeO2-BaF2-Y2O3 glasses and fabricated by using a rod-in-tube method. Under the pump of a 1570 nm Er3+-doped fiber laser, lasing at 1887 nm is obtained in a ∼42.5 cm long Tm3+-doped fiber with a threshold pump power of 94 mW. As the pump power increases to 780 mW, the obtained maximum unsaturated power reaches up to ∼408 mW with a slop efficiency of ∼58.1%. This result indicates that the Tm3+-doped fluorotellurite fibers are promising gain media for ∼2 μm fiber lasers.

  17. Upconversion properties of Er3+/Yb3+ co-doped TeO2-TiO2-K2O glasses.

    Science.gov (United States)

    Su, Fangning; Deng, Zaide

    2006-01-01

    The Er3+/Yb3+ co-doped TeO2-TiO2-K2O glasses were prepared by conventional melting procedures, and their upconversion spectra were performed. The dependence of luminescence intensity on the ratio of Yb3+/Er3+ was studied, and the relationship between green upconversion luminescence intensity and Er3+ concentration is discussed in detail. The 546 nm green upconversion luminescence intensity is optimised in the studied glasses either when the Yb3+/Er3+ ratio is 25/1 and Er3+ concentration is 0.1 mol%, or when the Yb3+/Er3+ ratio is 10/1 and Er3+ concentration is 0.15 mol%. These glasses could be one of the potential candidates for LD pumping microchip solid-state lasers.

  18. Ho3+/Yb3+ co-doped TeO2-BaF2-Y2O3 glasses for ∼1.2 μm laser applications

    Science.gov (United States)

    Wang, Shunbin; Li, Chengzhi; Yao, Chuanfei; Jia, Shijie; Jia, Zhixu; Qin, Guanshi; Qin, Weiping

    2017-02-01

    Intense ∼1.2 μm fluorescence is observed in Ho3+/Yb3+ co-doped TeO2-BaF2-Y2O3 glasses under 915 nm laser diode excitation. The 1.2 μm emission can be ascribed to the transition 5I6→5I8 of Ho3+. With the introducing of BaF2, the content of OH in the glasses drops markedly, and the 1.2 μm emission intensity increases gradually as increasing the concentration percentage of BaF2. Furthermore, microstructured fibers based on the TeO2-BaF2-Y2O3 glasses are fabricated by using a rod-in-tube method, and a relative positive gain of ∼9.42 dB at 1175.3 nm is obtained in a 5 cm long fiber.

  19. A P2-Type Layered Superionic Conductor Ga-Doped Na2 Zn2 TeO6 for All-Solid-State Sodium-Ion Batteries.

    Science.gov (United States)

    Li, Yuyu; Deng, Zhi; Peng, Jian; Chen, Enyi; Yu, Yao; Li, Xiang; Luo, Jiahuan; Huang, Yangyang; Zhu, Jinlong; Fang, Chun; Li, Qing; Han, Jiantao; Huang, Yunhui

    2018-01-24

    Here, a P2-type layered Na 2 Zn 2 TeO 6 (NZTO) is reported with a high Na + ion conductivity ≈0.6×10 -3  S cm -1 at room temperature (RT), which is comparable to the currently best Na 1+n Zr 2 Si n P 3-n O 12 NASICON structure. As small amounts of Ga 3+ substitutes for Zn 2+ , more Na + vacancies are introduced in the interlayer gaps, which greatly reduces strong Na + -Na + coulomb interactions. Ga-substituted NZTO exhibits a superionic conductivity of ≈1.1×10 -3  S cm -1 at RT, and excellent phase and electrochemical stability. All solid-state batteries have been successfully assembled with a capacity of ≈70 mAh g -1 over 10 cycles with a rate of 0.2 C at 80 °C. 23 Na nuclear magnetic resonance (NMR) studies on powder samples show intra-grain (bulk) diffusion coefficients D NMR on the order of 12.35×10 -12  m 2  s -1 at 65 °C that corresponds to a conductivity σ NMR of 8.16×10 -3  S cm -1 , assuming the Nernst-Einstein equation, which thus suggests a new perspective of fast Na + ion conductor for advanced sodium ion batteries. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Structural, morphological and optical investigations on electron-beam irradiated PbF2-TeO2-B2O3-Eu2O3 glasses

    Science.gov (United States)

    Wagh, Akshatha; Petwal, Vikash; Dwivedi, Jishnu; Upadhyaya, V.; Raviprakash, Y.; Kamath, Sudha D.

    2016-09-01

    Combined structural, optical and morphological studies were carried out on Eu2O3 doped PbF2-TeO2-B2O3 glass samples, before and after being subjected to electron beam of energy 7.5 MeV. XRD confirmed the amorphous nature of the glasses even after 150 kGy electron beam irradiation. Densities of the irradiated samples showed slightly greater values when compared to their respective values before irradiation, which proved the increase in the compaction of the network. The intensities of the three prominent bands; B-O-B linkages, BO4 units and BO3 units of FT-IR spectra, of the titled glasses, showed slight decrease after electron beam irradiation. The decrement in the values of energy band gap and shift in cut-off wavelength towards red edge, proved the formation of color centers in the glass network after irradiation. The change in Hunter L values, through color measurement was a proof for the Farbe/color/absorption centers created in the glass sites after irradiation.

  1. Emission analysis of RE3+ (RE = Sm, Dy):B2O3-TeO2-Li2O-AlF3 glasses.

    Science.gov (United States)

    Raju, C Nageswara; Sailaja, S; Kumari, S Pavan; Dhoble, S J; Kumar, V Ramesh; Ramanaiah, M V; Reddy, B Sudhakar

    2013-01-01

    This article reports on the optical properties of 0.5% mol of Sm(3+), Dy(3+) ion-doped B2O3-TeO2-Li2O-AlF3 (LiAlFBT) glasses. The glass samples were characterized by optical absorption and emission spectra. Judd-Ofelt theory was applied to analyze the optical absorption spectra and calculate the intensity parameters and radiative properties of the emission transitions. The emission spectra of Sm(3+) and Dy(3+):LiAlFBT glasses showed a bright reddish-orange emission at 598 nm ((4)G5/2 → (6)H7/2) and an intense yellow emission at 574 nm ((4)F9/2 → (6)H13/2), respectively. Full width at half maximum (FWHM), stimulated emission cross section, gain bandwidth and optical gain values were also calculated to extend the applications of the Sm(3+) and Dy(3+):LiAlFBT glasses. Copyright © 2012 John Wiley & Sons, Ltd.

  2. Spectroscopic and energy transfer studies of Er3+ ions in B2O3-TeO2-MgO-ZnO glasses

    Science.gov (United States)

    Vijayakumar, M.; Arunkumar, S.; Maheshvaran, K.; Marimuthu, K.

    2016-05-01

    Composition dependent spectroscopic behavior of Er3+ doped telluroborate glasses were prepared and the energy transfer mechanism in Er3+ ions were investigated for 1.532 µm amplification. The emission cross-section and gain coefficient for 4I13/2→4I15/2 level of Er3+ ions have been analysed through the Judd-Ofelt and McCumber theory. The excited state decay curves were measured and the effect of TeO2 on the lifetime for 4I13/2→4I15/2 level of Er3+ ions has been associated with the various energy transfer mechanism. Further the interaction between Er3+ and OH- were investigated and it was confirmed that the OH free radicals in the prepared glasses are dominant quenching center through the non-radiative relaxation that causes the quenching of 1.532 µm amplification. The non-radiative rate through the OH content were calculated and compared with the reported Er3+ doped glasses.

  3. Spectroscopic properties of the 1.4 microm emission of Tm3+ ions in TeO2-WO3-PbO glasses.

    Science.gov (United States)

    Balda, R; Lacha, L M; Fernández, J; Arriandiaga, M A; Fernández-Navarro, J M; Muñoz-Martin, D

    2008-08-04

    In this work, we report the spectroscopic properties of the infrared 3H4-->3F4 emission of Tm3+ ions in two different compositions of glasses based on TeO2, WO3, and PbO for three Tm2O3 concentrations (0.1,0.5, and 1 wt%). Judd-Ofelt intensity parameters have been determined and used to calculate the radiative transition probabilities and radiative lifetimes. The infrared emission at around 1490 nm corresponding to the 3H4-->F4 transition has two noticeable features if compared to fluoride glasses used for S-band amplifiers. On one hand, it is broader by nearly 30 nm, and on the other, the stimulated emission cross section is twice the value for fluoride glasses. Both the relative intensity ratio of the 1490 nm emission to 1820 nm and the measured lifetime of the 3H4 level decrease as concentration increases, due to the existence of energy transfer via cross-relaxation among Tm3+ ions. The analysis of the decays from the 3H4 level with increasing concentration indicates the presence of a dipole-dipole quenching process assisted by energy migration.

  4. Raman, FTIR, thermal and optical properties of TeO2-Nb2O5-B2O3-V2O5 quaternary glass system

    Directory of Open Access Journals (Sweden)

    Swapna

    2017-07-01

    Full Text Available A series of quaternary glass systems with the composition 79TeO2-(20−xNb2O5-xB2O3-1V2O5 was prepared using the melt quench technique. Such studies as optical absorption, Raman, FTIR spectroscopy, EPR and DSC were carried out on the glass system. The physical properties, such as density (ρ and molar volume (VM, were determined. The Urbach energy (ΔE, optical band gap (Eopt, optical basicity (Λ, refractive index (n and electron polarizability (α of the glasses were determined from optical absorption data. Spin-Hamiltonian parameters of VO2+ ions were calculated from the EPR data. With the gradual substitution of B2O3 at the expense of Nb2O5, the density and optical band gap of the glasses decreased, and the electronic polarizability increased. EPR spectra revealed that VO2+ occupies an octahedral site with tetrahedral compression. Spin-Hamiltonian parameters g|| and g⊥ increased as B2O3 content increased in the glass. The glass transition temperature (Tg also decreased as the B2O3 content in the glass increased.

  5. Broadband ˜2μm emission in Tm3+/Ho3+ co-doped TeO2-WO3-La2O3 glass

    Science.gov (United States)

    Li, Kefeng; Wang, Guonian; Zhang, Junjie; Hu, Lili

    2010-10-01

    In this work, we report the infrared emission properties of Tm 3+/Ho 3+ co-doped TeO 2-WO 3-La 2O 3 (TWL) glass under 808 nm laser excitation. A broad and flat emission from 1600 to 2200 nm corresponding to the Tm 3+ ( 3F 4→ 3H 6) and Ho 3+ ( 5I 7→ 5I 8) emissions is observed. The full width at half maximum (FWHM) of this broadband increases up to a value of ˜370 nm with an optimal [Tm 3+]/[Ho 3+] concentration ratio. The energy transfer processes of Tm 3+↔Ho 3+ are analyzed and the results show that energy transfer between Tm 3+ and Ho 3+ plays an important role in the luminescence mechanism. The OH - influence on the broadband emission is also discussed. These results indicate that Tm 3+-Ho 3+ co-doped TWL glass could be a promising material for widely tunable laser or broadband amplifier applications.

  6. Thermomechanical Properties of Sb2O3-TeO2-V2O5 Glassy Systems: Thermal Stability, Glass Forming Tendency and Vickers Hardness

    Science.gov (United States)

    Souri, Dariush; Torkashvand, Ziba

    2017-04-01

    Three-component 40TeO2-(60- x)V2O5- xSb2O3 glasses with 0 ≤ x ≤ 10 (in mol.%) were obtained by the rapid melt-quenching method. These glasses were studied with respect to some mechanical properties with the goal of obtaining information about their structure. The Vickers hardness test was employed to obtain Vickers micro-hardness ( H V) at two different loads, which was within the range of 13.187-17.557 GPa for a typical 0.1 HV (0.9807 N) load. In addition, theoretical micro-hardness ( H) was investigated and compared with experimental H V, showing the elevating trend with increase of Sb2O3 content, as for H V. Furthermore, differential scanning calorimetry (DSC) was employed within the range of 150-500°C at heating rates of φ = 3 K/min, 6 K/min, 9 K/min, 10 K/min, and 13 K/min. In this work, thermal stability ( T s = T cr - T x) and glass forming tendency ( K gl) were measured and reported for these glasses to determine the relationship between the chemical composition and the thermal stability, in order to interpret the structure of glass. Generally, from the ascertained outputs [analysis of mechanical data, titration study, the values of reduced fraction of vanadium ions ( C V) and oxygen molar volume ( V_{{O}}^{*} )], it was found that the micro-hardness had an increasing trend with increasing the Sb2O3 content. Among the studied glasses, the sample with x = 8 had a higher average micro-hardness value, the highest average thermal stability and glass forming tendency with respect to the other samples, which makes it a useful material (owning very good resistance against thermal attacks) for device manufacturing.

  7. Optical spectroscopy of Sm(3+) doped Na2O-ZnO-La2O3-TeO2 glasses.

    Science.gov (United States)

    Sobczyk, Marcin

    2015-10-05

    Telluride glasses with the composition xSm2O3-(7-x)La2O3-3Na2O-25ZnO-65TeO2 (where x=0.1, 1, 2, 5 and 7 mol%) were obtained by the melt quenching technique. Electronic absorption and fluorescence spectra as well as fluorescence dynamics of the Sm(3+)-doped title glasses are presented and analysed in detail. A Judd-Ofelt intensity analysis of the absorption spectrum at 300 K has been applied for determination of Ωλ parameters (Ω2=3.10, Ω4=3.80, Ω6=1.61×10(-20) cm(2)) which in turn have been used for calculations of the radiative transition probabilities (AT), the natural (radiative) lifetimes (τR) of the (4)G5/2 level of Sm(3+), the fluorescence branching ratios (β) and the emission cross-sections (σem). The τR value of the (4)G5/2 level amount to 1546 μs and is slightly higher than the measured decay time of 1306 μs. With the increasing of Sm2O3 concentration from 0.1 to 7.0 mol% the experimental lifetime of the fluorescent level decreases from 1306 to 41 μs. An analysis of the non-radiative decay was based on the cross-relaxation mechanisms. The optical achieved results indicate that the investigated glasses are potentially applicable as an orange and/or red laser host. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Nd3+-doped TeO2-Bi2O3-ZnO transparent glass ceramics for laser application at 1.06 μm

    Science.gov (United States)

    Hu, Xiaolin; Luo, Zhiwei; Liu, Taoyong; Lu, Anxian

    2017-04-01

    The high crystallinity transparent glass ceramics based on Nd3+-doped 70TeO2-15Bi2O3-15ZnO (TBZ) compositions were successfully prepared by two-step heat treatment process. The effects of Nd2O3 content on the thermal, structural, mechanical, and optical properties of TBZ glass ceramics were studied. The incorporation of Nd2O3 enhanced the crystallization tendency in the matrix glass composition. The crystal phase and morphology of Bi2Te4O11 in the glass ceramics were confirmed by X-ray diffraction and field emission scanning electron microscopy. Due to precipitate more crystal phase, the hardness values increased from 3.21 to 3.66 GPa. Eight absorption peaks were observed from 400 to 900 nm and three emission bands appeared in the range of 850-1400 nm. With the increasing of Nd2O3 content from 0.5 to 2.5 wt%, the intensity of absorption peaks enhanced and the emission intensity increased up to 1.0 wt% and then fell down for further dopant concentration. The fluorescence decay lifetime decreased rapidly starting from 1.5 wt% Nd2O3 content due to the obvious energy migration among Nd3+. According to the extreme strong emission band around 1062 nm and the optimum Nd2O3 content (1.0 wt%), N10 glass ceramic was considered as a potential material for 1.06 μm laser applications.

  9. One-step fabrication of highly stable, superhydrophobic composites from controllable and low-cost PMHS/TEOS sols for efficient oil cleanup.

    Science.gov (United States)

    Guo, Ping; Zhai, Shangru; Xiao, Zuoyi; An, Qingda

    2015-05-15

    Facing the issues of significant increase of industrial oily wastewater and frequent accident of oil spills, the developing of efficient and affordable absorbents for improving oil pollution is of practical significance. Herein, several superhydrophobic and superoleophilic materials, utilizing filter paper, filter cloth and polyester sponge as substrates, through facile coating of hybrid SiO2 colloid particles from controllable PMHS-TEOS sol system were presented. These methyl-modified particles not only provided hierarchical micro/nano-scale structure with distinct roughness, but also largely lowered the surface energy of the coated substances, leading to excellent superhydrophobic and superoleophilic surfaces. The modified filter cloths could be applied for oil/water separation owing to the flexible and foldable property; sponges could efficiently absorb oil or organic solvents in situ on account of its low density and high porosity, and meanwhile the absorbed oil could be easily recollected by simple squeezing. It is worth mentioning that both modified filter cloths and sponges exhibited excellent selectivity, high efficiency, outstanding rapidity and remarkable recyclability. More importantly, after treatment of 100 abrasion cycles with metal scalpel and strongly acidic and basic water droplets, the whole WCA values of resultant filter cloths still maintained superhydrophobic character (>150°), illuminating the charming mechanical and chemical stability of sol-gel processed coating with hierarchical roughness and covalently bonded methyl groups. Combining controllable fabrication process and cheap raw precursors, this method enables scalable manufacturing of stable and superhydrophobic substances, which are promising in practical applications involved in oil/water separation and oil sorption. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Dispersion and guidance characteristics of microstructured 68TeO2 - 22WO3 - 8La2O3 - 2Bi2O3 glass fibres for supercontinuum generation

    International Nuclear Information System (INIS)

    Yatsenko, Yu P; Nazaryants, V O; Kosolapov, A F; Astapovich, M S; Plotnichenko, V G; Dianov, Evgenii M; Moiseev, A N; Churbanov, M F; Dorofeev, V V; Chilyasov, A V; Snopatin, G E

    2010-01-01

    We report the preparation of a high-purity optical-quality four-component glass of composition 68TeO 2 - 22WO 3 - 8La 2 O 3 - 2Bi 2 O 3 , containing (2.7±0.5)x10 -5 mol % OH groups. Its refractive index has been determined in the range 0.9 - 5.45 μm using interference refractometry. The data are used to assess the dispersion and guidance characteristics of microstructured optical fibres potentially attractive for supercontinuum generation in the range 1 - 5 μm (optical fibres)

  11. Structural and luminescence studies of Eu3+: TeO2sbnd B2O3sbnd AOsbnd AF2 (A = Pb, Ba, Zn, Cd, Sr) glasses

    Science.gov (United States)

    Selvi, S.; Marimuthu, K.; Muralidharan, G.

    2017-09-01

    Eu3+ doped oxyfluoro boro-tellurite (TBXFE) with molar composition 29 TeO2sbnd 30B2O3sbnd 20AOsbnd 20AF2sbnd 1Eu2O3 (where A = Pb, Ba, Zn, Cd, Sr) glasses were prepared and investigated by XRD, FTIR, UV-Vis-NIR, luminescence and decay measurements. XRD patterns confirm the glassy nature of the prepared glasses. The influence of metal ions on the structure of boro-tellurite glasses were investigated through FTIR spectra. The intra band (4f-4f) transitions of Eu3+ ions are discussed through UV-Vis-NIR absorption spectra. The covalent nature around the Eu3+ ions with ligands are discussed using the bonding parameter (δ) and nephelauxetic ratio (β). The fundamental absorption edge, direct, indirect band gap, Urbach energy and band tailing parameters are reported. A bright red emission at 616 nm corresponding to the 5D0 → 7F2 transition of Eu3+ ions could be observed in the title glasses. Judd-Ofelt parameters were estimated from the emission spectra of Eu3+ ions. The dependence of these parameters on the composition of the glass is discussed. Judd-Ofelt parameters were used to derive the radiative parameters such as transition probabilities (A, s-1), branching ratios (βR), radiative lifetime (τrad) and stimulated emission cross-section (σPE) for the 5D0 → 7FJ (J = 0, 1, 2, 3 and 4) transitions. The luminescence intensity ratio (LIR) of 5D0 → 7F2/5D0 → 7F1 transitions was estimated to analyze the local site symmetry around the Eu3+ ions in the present glasses. The chromaticity coordinates and colour purity were calculated from the emission spectra and analyzed with Commission International de I'Eclairage (CIE) 1931 diagram. The experimental lifetime of 5D0 level could be fitted to a single exponential indicating the absence of energy transfer between the Eu3+ ions in the present glasses.

  12. Análise histomorfométrica da matriz extracelular do linfonodo poplíteo de cães naturalmente infectados por Leishmania (L. chagasi

    Directory of Open Access Journals (Sweden)

    Kris Régia J. Kondo

    2009-08-01

    Full Text Available Nas Américas, a leishmaniose visceral canina é causada por Leishmania (Leishmania chagasi, um protozoário intracelular obrigatório do sistema fagocítico mononuclear; as principais alterações histológicas associadas a essa doença ocorrem nos em órgãos linfóides. Apesar de o cão ser considerado o principal mantenedor e disseminador da leishmaniose no ambiente urbano, são escassos estudos dos aspectos histopatológicos e histomorfométricos, em cães naturalmente infectados com L. chagasi, que investiguem a interação entre o parasito e a matriz extracelular. Este estudo visou caracterizar e quantificar as alterações dos componentes celulares e da matriz extracelular (colágenos I e III do linfonodo poplíteo de 22 cães com infecção natural por L. chagasi detectada através da reação de imunofluorescência indireta (RIF e compará-las com as alterações encontradas no linfonodo poplíteo de 10 cães não-infectados, negativos na RIF e clinicamente saudáveis. Fragmentos dos linfonodos foram seccionados longitudinalmente, processados rotineiramente para exame histológico e corados por hematoxilina-eosina. Cortes adicionais do mesmo linfonodo incluídos em glicol metacrilato foram corados pelo azul de toluidina para histomorfometria. Linfonodos de cães infectados apresentaram linfadenopatia generalizada, aumento do tamanho e do número dos folículos linfóides, hipertrofia da cápsula e hiperplasia linfóide significativa. Nos linfonodos de cães do grupo infectado, a análise quantitativa de fibras colágenas mostrou significativo predomínio do colágeno I sobre o colágeno III. Esses resultados demonstram que cães infectados por L. chagasi apresentam degradação dos constituintes da matriz extracelular e conseqüente destruição do arcabouço linfóide, alterando a morfologia do órgão.In the Americas, canine visceral leishmaniasis is caused by Leishmania (Leishmania chagasi, an obligatory intracellular parasite of

  13. Investigation of radiation shielding properties for MeO-PbCl2-TeO2 (MeO = Bi2O3, MoO3, Sb2O3, WO3, ZnO) glasses

    Science.gov (United States)

    Sayyed, M. I.; Çelikbilek Ersundu, M.; Ersundu, A. E.; Lakshminarayana, G.; Kostka, P.

    2018-03-01

    In this work, glasses in the MeO-PbCl2-TeO2 (MeO = Bi2O3, MoO3, Sb2O3, WO3, ZnO) system, which show a great potential for optoelectronic applications, were used to evaluate their resistance under high energy ionizing radiations. The basic shielding quantities for determining the penetration of radiation in glass, such as mass attenuation coefficient (μ/ρ), half value layer (HVL), mean free path (MFP) and exposure buildup factor (EBF) values were investigated within the energy range 0.015 MeV ‒ 15 MeV using XCOM program and variation of shielding parameters were compared with different glass systems and ordinary concrete. From the derived results, it was determined that MeO-PbCl2-TeO2 (MeO = Bi2O3, MoO3, Sb2O3, WO3, ZnO) glasses show great potentiality to be used under high energy radiations. Among the studied glass compositions, Bi2O3 and WO3 containing glasses were found to possess superior gamma-ray shielding effectiveness.

  14. Shielding properties of 80TeO2–5TiO2–(15−x) WO3–xAnOm glasses using WinXCom and MCNP5 code

    International Nuclear Information System (INIS)

    Dong, M.G.; El-Mallawany, R.; Sayyed, M.I.; Tekin, H.O.

    2017-01-01

    Gamma ray shielding properties of 80TeO 2 –5TiO 2 –(15−x) WO 3 –xA n O m glasses, where A n O m is Nb 2 O 5 = 0.01, 5, Nd 2 O 3 = 3, 5 and Er 2 O 3 = 5 mol% have been achieved. Shielding parameters; mass attenuation coefficients, half value layers, and macroscopic effective removal cross section for fast neutrons have been computed by using WinXCom program and MCNP5 Monte Carlo code. In addition, by using Geometric Progression method (G-P), exposure buildup factor values were also calculated. Variations of shielding parameters are discussed for the effect of REO addition into the glasses and photon energy. - Highlights: • The shielding properties of 80TeO 2 –5TiO 2 –(15−x) WO 3 –xA n O m glasses were evaluated. • WinXCom program and MCNP simulation codes were used in the calculations. • Good agreement was noticed between the WinXCom and MCNP5 code results.

  15. CO gas sensing properties of In_4Sn_3O_1_2 and TeO_2 composite nanoparticle sensors

    International Nuclear Information System (INIS)

    Mirzaei, Ali; Park, Sunghoon; Sun, Gun-Joo; Kheel, Hyejoon; Lee, Chongmu

    2016-01-01

    Highlights: • In4Sn3O12–TeO2 composite nanoparticles were synthesized via a facile hydrothermal route. • The response of the In4Sn3O12–TeO2 composite sensor to CO was stronger than the pristine In4Sn3O12 sensor. • The response of the In4Sn3O12–TeO2 composite sensor to CO was faster than the pristine In4Sn3O12 sensor. • The improved sensing performance of the In4Sn3O12–TeO2 nanocomposite sensor is discussed in detail. • The In4Sn3O12-based nanoparticle sensors showed selectivity to CO over NH3, HCHO and H2. - Abstract: A simple hydrothermal route was used to synthesize In_4Sn_3O_1_2 nanoparticles and In_4Sn_3O_1_2–TeO_2 composite nanoparticles, with In(C_2H_3O_2)_3, SnCl_4, and TeCl_4 as the starting materials. The structure and morphology of the synthesized nanoparticles were examined by X-ray diffraction and scanning electron microscopy (SEM), respectively. The gas-sensing properties of the pure and composite nanoparticles toward CO gas were examined at different concentrations (5–100 ppm) of CO gas at different temperatures (100–300 °C). SEM observation revealed that the composite nanoparticles had a uniform shape and size. The sensor based on the In_4Sn_3O_1_2–TeO_2 composite nanoparticles showed stronger response to CO than its pure In_4Sn_3O_1_2 counterpart. The response of the In_4Sn_3O_1_2–TeO_2 composite-nanoparticle sensor to 100 ppm of CO at 200 °C was 10.21, whereas the maximum response of the In_4Sn_3O_1_2 nanoparticle sensor was 2.78 under the same conditions. Furthermore, the response time of the composite sensor was 19.73 s under these conditions, which is less than one-third of that of the In_4Sn_3O_1_2 sensor. The improved sensing performance of the In_4Sn_3O_1_2–TeO_2 nanocomposite sensor is attributed to the enhanced modulation of the potential barrier height at the In_4Sn_3O_1_2–TeO_2 interface, the stronger oxygen adsorption of p-type TeO_2, and the formation of preferential adsorption sites.

  16. Optical properties of nanocrystalline potassium lithium niobate in the glass system (100-x) TeO2-x(1.5K2O-Li2O-2.5Nb2O5).

    Science.gov (United States)

    Ahamad, M Niyaz; Varma, K B R

    2009-08-01

    Optically clear glasses of various compositions in the system (100-x) TeO2-x(1.5K2O-Li2O-2.5Nb2O5) (2 glasses comprising potassium lithium niobate (K3Li2Nb5O15) microcrystallites on the surface and nanocrystallites within the glass were obtained by controlled heat-treatment of the as-quenched glasses just above the glass transition temperature (T(g)). The optical transmission spectra of these glasses and glass-crystal composites of various compositions were recorded in the 200-2500 nm wavelength range. Various optical parameters such as optical band gap, Urbach energy, refractive index were determined. Second order optical non-linearity was established in the heat-treated samples by employing the Maker-Fringe method.

  17. Shielding properties of 80TeO2-5TiO2-(15-x) WO3-xAnOm glasses using WinXCom and MCNP5 code

    Science.gov (United States)

    Dong, M. G.; El-Mallawany, R.; Sayyed, M. I.; Tekin, H. O.

    2017-12-01

    Gamma ray shielding properties of 80TeO2-5TiO2-(15-x) WO3-xAnOm glasses, where AnOm is Nb2O5 = 0.01, 5, Nd2O3 = 3, 5 and Er2O3 = 5 mol% have been achieved. Shielding parameters; mass attenuation coefficients, half value layers, and macroscopic effective removal cross section for fast neutrons have been computed by using WinXCom program and MCNP5 Monte Carlo code. In addition, by using Geometric Progression method (G-P), exposure buildup factor values were also calculated. Variations of shielding parameters are discussed for the effect of REO addition into the glasses and photon energy.

  18. Primera evidencia experimental mediante microscopía electrónica de transmisión de la disociación de dislocaciones en el sistema TeO2

    Directory of Open Access Journals (Sweden)

    Castaing, J.

    2005-10-01

    Full Text Available This work intends to analyse the microstructure of paratellurite (TeO2 single crystals plastically deformed at high temperature (∼870 K in uniaxial compression along [110]. Samples have been mechanically tested, and thin foils have been cut from them, corresponding to the slip systems to be observed in transmission electron microscopy. The study of the dislocation substructure in this material is rather complex due to its high anisotropy. Microstructural observation by TEM has put into evidence the presence of dislocation dissociation. This is the first work reporting this fact. From the equilibrium distance between partials, an estimation of the stacking fault energy has been carried out.En este trabajo se pretende analizar la microestructura de monocristales de TeO2 (paratelurita deformados plásticamente en compresión uniaxial a alta temperatura (∼870 K en distintas condiciones. Para ello, se han ensayado muestras con orientación cristalográfica [110], y se han cortado láminas correspondientes a los planos de deslizamiento para ser observadas con microscopía electrónica de transmisión. El estudio de la subestructura de dislocaciones en este material es complejo debido a su alta anisotropía. La observación de dicha microestructura ha puesto de manifiesto la presencia de disociación de dislocaciones. Es la primera vez que se encuentra este fenómeno en la paratelurita. De la distancia de equilibrio entre dislocaciones parciales, se ha podido obtener una estimación de la energía de falta de apilamiento en este sistema.

  19. Investigation of thermal stability and spectroscopic properties in Er3+/Yb3+-codoped TeO2-Li2O-B2O3-GeO2 glasses.

    Science.gov (United States)

    Nie, Qiu-Hua; Gao, Yuan; Xu, Tie-Feng; Shen, Xiang

    2005-06-01

    The new Er3+/Yb3+ co-doped 70TeO2-5Li2O-(25-x)B2O3-xGeO2 (x = 0, 5, 10, 15 fand 20 mol.%) glasses were prepared. The thermal stability, absorption spectra, emission spectra and lifetime of the 4I(13/2) level of Er3+ ions were measured and studied. The FT-IR spectra were carried out in order to investigate the structure of local arrangements in glasses. It is found that the thermal stability, absorption cross-section of Yb3+, emission intensity and lifetime of the 4I(13/2) level of Er3+ increase with increasing GeO2 content in the glass composition, while the fluorescence width at half maximum (FWHM) at 1.5 um of Er3+ is about 70 nm. The obtained data suggest that this system glass can be used as a candidate host material for potential broadband optical amplifiers.

  20. Laser-diode-excited blue upconversion in Tm3+/Yb3+ -codoped TeO2-Ga2O3-R2O (R=Li, Na, K) glasses.

    Science.gov (United States)

    Zhao, Chun; Zhang, Qinyuan; Yang, Gangfeng; Jiang, Zhonghong

    2008-01-01

    This paper reports on intense blue upconversion in Tm(3+)/Yb(3+) codoped TeO(2)-Ga(2)O(3)-R(2)O(R=Li, Na, K) glasses upon excitation with commercial available laser diode (LD). Effects of alkali ions on the Raman spectra, thermal stability and spectroscopic properties of the tellurite-gallium glasses have also been investigated. Energy transfer and the involved upconversion mechanisms have been discussed. Intense blue upconversion emission centered at 476 nm along with a weak red emission at 650 nm has been observed upon excitation of 977 nm LD, assigned to the transitions of 1G4-->3H6, and 1G4-->3H4 and/or 3F(2,3)-->3H6 of Tm(3+), respectively. The blue upconversion intensity has a cubelike dependence on incident pump laser power, indicating a three-photon process. However, a quadratic dependence of the 476 nm upconversion intensity on the incident pump laser power has been observed when samples under excitation of 808 nm LD due to a two-photon absorption process. Enhanced upconversion luminescence have been observed with replacing K(+) for Na(+) and Li(+).

  1. Preparation and optical properties of TeO2-BaO-ZnO-ZnF2 fluoro-tellurite glass for mid-infrared fiber Raman laser applications

    Science.gov (United States)

    Li, Jie; Xiao, Xusheng; Gu, Shaoxuan; Xu, Yantao; Zhou, Zhiguang; Guo, Haitao

    2017-04-01

    A serial of novel fluoro-tellurite glasses with compositions of 60TeO2-20BaO-(20-x)ZnO-xZnF2 (x = 0, 2, 4, 5 and 6 mol%) were prepared. The compositional dependences of glass structural evaluation, Raman gain coefficient, UV-Vis transmission spectrum, IR transmission spectrum, linear refractive index and third-order nonlinearity were analyzed. The results showed that the addition of 6 mol% ZnF2 can further improve the Raman gain coefficient to as well as 52 × 10-11 cm/W and effectively decrease around 73% and 57% absorption coefficients respectively caused by free Osbnd H groups (@3.3 μm) and hydrogen-bonded Osbnd H groups (@4.5 μm) in glass. Addition of ZnF2 does not change the UV-Vis absorption edge, optical band gap energy and infrared region cut-off edge almost, while the linear refraction index and ultrafast third-nonlinearity show unmonotonic changes. These novel fluoro-tellurite glasses may be suitable candidates for using in mid-infrared Raman fiber laser and/or amplifier.

  2. Structural and luminescent study of TeO2-BaO-Bi2O3-Ag glass system doped with Eu3+ and Dy3+ for possible color-tunable phosphor application

    Science.gov (United States)

    Lewandowski, Tomasz; Seweryński, Cezary; Walas, Michalina; Łapiński, Marcin; Synak, Anna; Sadowski, Wojciech; Kościelska, Barbara

    2018-05-01

    Tellurite glass systems of 73TeO2-4BaO-3Bi2O3-1Ag:xEu2O3-(2-x)Dy2O3 (where x = 0.5, 1, 1.5, 2 in molar ratio) composition have been successfully synthesized. In order to acquire Ag nanoparticles, materials have been heat treated at 350 °C in the air atmosphere. Structural properties of obtained samples were evaluated with various techniques. X-Ray Diffraction (XRD) measurements indicated that obtained materials are amorphous in nature. UV-vis results presented transitions characteristic to Dy3+ and Eu3+ ions. Additionally, X-Ray Photoelectron Spectroscopy (XPS) analysis indicated the presence of silver in metallic form. Photoluminescence measurements shown influence of Ag nanoparticles on emission characteristics. Simultaneous emission of Dy3+ and Eu3+ has been observed when samples were excited with λexc = 390 nm. Change of the emission color induced by heat treatment has been observed and described in case of x = 1 glass series. According to CIE results emission color changes as Eu/Dy ratio and heat treatment time are changed. Emission shifts from reddish-orange to yellowish white color. Obtained photoluminescence results confirm that synthesized materials are good candidates for color tunable phosphors.

  3. Spectroscopic properties and thermal stability of Er3+ -doped TeO2-B2O3-Nb2O5-ZnO glass for potential WDM amplifier.

    Science.gov (United States)

    Xu, Tiefeng; Zhang, Xudong; Li, Guangpo; Dai, Shixun; Nie, Qiuhua; Shen, Xiang; Zhang, Xianghua

    2007-06-01

    A series of novel 70TeO2-(15-x)B2O3-xNb2O5-15ZnO-1wt.% Er2O3 (TBN x=0, 3, 6, 9, 12 and 15 mol%) tellurite glasses were prepared. The thermal stability, absorption spectra, emission spectra, and the lifetime of the (4)I(13/2) level of Er(3+) ions were measured and investigated. Three Judd-Ofelt intensity parameters Omega(t) (t=2, 4 and 6) (Omega(2)=(5.42-6.76)x10(-20)cm(2); Omega(4)=(1.37-1.73)x10(-20)cm(2); Omega(6)=(0.70-0.94)x10(-20)cm(2)) of Er(3+) ions were calculated by Judd-Ofelt theory. It is found that the Omega(6) first increases with the increase of Nb2O5 content from 0 to 6 mol% and then decreases, which is mainly affected by the number of non-bridging oxygen ions of the glass network. The high peak of stimulated emission cross-section (sigma(e)(peak)=(0.77-0.91)x10(-20)cm(2)) of Er(3+): (4)I(13/2)-->(4)I(15/2) transition were obtained according to McCumber theory and broad full width at half maximum (FWHM=65-73 nm) of the (4)I(13/2)-->(4)I(15/2) transition of Er(3+) ions were measured. The results indicate that these new TBN glasses can be used as a candidate host material for potential broadband optical amplifiers.

  4. Reddish-orange, neutral and warm white emissions in Eu3+, Dy3+ and Dy3+/Eu3+ doped CdO-GeO2-TeO2 glasses

    Science.gov (United States)

    Rodríguez-Carvajal, David A.; Meza-Rocha, A. N.; Caldiño, U.; Lozada-Morales, R.; Álvarez, E.; Zayas, Ma. E.

    2016-11-01

    Eu3+, Dy3+ and Dy3+/Eu3+ doped CdO-GeO2-TeO2 glasses were prepared using the melt-quenching process and analyzed by X-diffraction, Raman spectroscopy, excitation and emission spectra, and emission decay time profiles. The lack of X ray diffraction peaks revealed that all samples are amorphous. Vibrational modes associated with Tesbnd Osbnd Te and Gesbnd Osbnd Ge related bonds and molecular oxygen were detected by Raman spectroscopy. The luminescence characteristics were studied upon excitations that correspond with the emission of InGaN (370-420 nm) based LEDs. The Eu3+ singly doped glass displayed reddish-orange global emission, with x = 0.601 and y = 0.349 CIE1931 chromaticity coordinates, upon 393 nm excitation. Neutral emission with x = 0.373 and y = 0.412 CIE1931 chromaticity coordinates and correlated color temperature (CCT) of 4400 K, was achieved in the Dy3+ singly doped glass excited at 388 nm. The Dy3+/Eu3+ co-doped glass exhibited warm, neutral and soft warm white emissions with CCT values of 3435, 4153 and 2740 K, under excitations at 382, 388 and 393 nm, respectively, depending mainly on the Dy3+ and Eu3+ relative excitation. The Dy3+ excitation bands observed in the Dy3+/Eu3+ glass by monitoring the 611 nm Eu3+ emission, suggest that Dy3+ → Eu3+ energy transfer takes place, despite the fact that the Dy3+ emission decays in the Dy3+ and Dy3+/Eu3+ doped glass, remain without changes. The shortening of Eu3+ decay in presence of Dy3+ was attributed to an Eu3+ → Dy3+ non-radiative energy transfer process, which according with the Inokuti-Hirayama model might be dominated through an electric quadrupole-quadrupole interaction, with efficiency and probability of 5.5% and 51.6 s-1, respectively.

  5. Electrical studies of D%AgI-(100-D)%[0.667Ag2O- 0.333{(0.4)B2O3-(0.6)TeO2}] fast ion conducting glasses

    Science.gov (United States)

    Kumar, E. Ramesh; Nageswar Rao, P.; Appa Rao, B.

    2016-09-01

    Super ion conducting glasses of composition D%AgI-(100-D)%[MAg2O-F{(F1)B2O3- (F2)TeO2}]; D=10.0 to 60.0 in steps of 10.0 for a fixed values of F1 (0.4), F2 (0.6) which are glass network formers, fixed values of modifier M(0.667), F (0.333) and D is dopant salt which was varied. These glasses were prepared by melt quenching technique. XRD spectra taken for all the samples. Electrical characterization was done in terms of AC and DC conductivities. DC and AC conductivities at room temperature increased from 10-5 to 10-1 scm-1 and DC activation energy (Edc) found to decrease from 0.36 to 0.19eV with increase in D% ratio. Measurements are performed over the frequency range 1 kHz to 3 MHz at different temperatures. From the impedance spectroscopy real and imaginary parts of impedances (Z', Z"), conductivities were calculated and plotted, and equivalent R-C circuit parameters were obtained from Cole-Cole plots. With the increase in D%, AC conductivity is observed to increase whereas the AC activation energy (Eac) is observed to decrease from 0.23 to 0.14 eV. The quantitative analysis of these results indicates that the electrical conductivity of silver borate glasses is enhanced with increase in D% ratio. Based on conductivity values these glasses are ionic conductors, in which conduction is by hopping mechanism. An attempt is made to understand the charge transportation process.

  6. Influence of valence state of copper ions on structural and spectroscopic properties of multi-component PbO-Al2O3-TeO2-GeO2-SiO2 glass ceramic system- a possible material for memory switching devices

    Science.gov (United States)

    Tirupataiah, Ch.; Narendrudu, T.; Suresh, S.; Srinivasa Rao, P.; Vinaya Teja, P. M.; Sambasiva Rao, M. V.; Chinna Ram, G.; Krishna Rao, D.

    2017-11-01

    Multi-component glass ceramics with composition 29PbO-5Al2O3-1TeO2 -10GeO2- (55-x) SiO2 doped with different concentrations of CuO (0 ≤ x ≤ 1.0 mol %) were synthesized by melt quenching technique and subsequent heat treatment. These glass ceramics were characterized by X-ray diffraction, scanning electron microscope, differential thermal analysis, optical absorption, electron paramagnetic resonance, Fourier transform infrared and Raman studies. The absorption spectra of these glass ceramics exhibited a broad absorption band in the range 650-950 nm which is ascribed to 2B1g → 2B2g octahedral transition of Cu2+ ions. A feeble band around 364 nm is also identified in the samples doped with CuO up to 0.6 mol% as being due to charge transfer between the two oxidation states Cu2+ and Cu+ of copper ions. The EPR spectrum recorded at room temperature exhibited a strong resonance signal at g⊥ = 2.072 and a shallow quadruplet at about gǁ = 2.401. FTIR and Raman spectra of the titled samples provide significant information about various structural units viz., silicate, germanate, PbO4, PbO6, AlO6, TeO4 and TeO3 that are present in these ceramic matrix. Analysis of the spectroscopic investigations reveals that with an increase in the concentration of CuO up to 0.6 mol% copper ions do exist in Cu2+ and Cu+ states and they act as modifiers and net work formers respectively. Therefore, glass ceramic sample contains 0.6 mol% of CuO is favorable for memory switching action.

  7. Ilmus teos "Rektor Johan Kõpp" / Aksel Mark

    Index Scriptorium Estoniae

    Mark, Aksel, 1913-2014

    2007-01-01

    rets. rmt.: Rohtmets, Priit. Rektor Johan Kõpp / toimetaja Mart Orav; resümeede tõlge: saksa keelde Reet Bender, inglise keelde Saskia Kangro, vene keelde A&A Lingua; kujundus Kalle Toompere. Tallinn : Aasta Raamat, 2007. 144 lk.

  8. Jean Piaget' teos mõttestruktuuridest

    Index Scriptorium Estoniae

    2002-01-01

    TPÜ kasvatusteaduste teaduskond esitles 29. okt. 2002.a. Šveitsi psühholoogi Jean Piaget' ja Alina Szeminska teost "Arvumõiste kujunemine lapsel". Kommenteerib TPÜ psühholoogiaprofessor Voldemar Kolga

  9. Measurements of defect structures by positron annihilation lifetime spectroscopy of the tellurite glass TeO2-P2O5-ZnO-LiNbO3 doped with ions of rare earth elements: Er3+, Nd3+ and Gd3+

    Science.gov (United States)

    Golis, E.; Yousef, El. S.; Reben, M.; Kotynia, K.; Filipecki, J.

    2015-12-01

    The objective of the study was the structural analysis of the TeO2-P2O5-ZnO-LiNbO3 tellurite glasses doped with ions of the rare-earth elements: Er3+, Nd3+ and Gd3+ based on the PALS (Positron Annihilation Lifetime Spectroscopy) method of measuring positron lifetimes. Values of positron lifetimes and the corresponding intensities may be connected with the sizes and number of structural defects, such as vacancies, mono-vacancies, dislocations or pores, the sizes of which range from a few angstroms to a few dozen nanometres. Experimental positron lifetime spectrum revealed existence of two positron lifetime components τ1 and τ2. Their interpretation was based on two-state positron trapping model where the physical parameters are the annihilation velocity and positron trapping rate.

  10. Spectral properties and anti-Stokes luminescence of TeO2-BaF2:Ho3+, Ho3+/Yb3+ ceramics and glass excited by 1.9-μm radiation of a Tm:LiYF4 laser

    Science.gov (United States)

    Savikin, A. P.; Egorov, A. S.; Budruev, A. V.; Perunin, I. Yu.; Krasheninnikova, O. V.; Grishin, I. A.

    2017-07-01

    We demonstrate the up-conversion of Tm:LiYF4 infrared (IR) laser radiation with 1908-nm wavelength into visible light with a spectral maximum at 650 nm by ceramics with a composition of (100 - x)TeO2- xBaF2 - 1 wt % HoF3- yYbF3, where x = 20, 30, or 40 mol % and y = 0 or 0.5 wt %. The samples of 60TeO2-40BaF2 - 1 wt % HoF3 - 0.5 wt % YbF3 exhibited anti-Stokes luminescence at a threshold radiation power density of 1.0-1.5 W cm-2.

  11. Diseño de recubrimientos multicapa barrera-biomimético base TEOS-GPTMS sobre la aleación de magnesio Elektron 21 de potencial aplicación en la fabricación de implantes ortopédicos

    Directory of Open Access Journals (Sweden)

    Rueda, Laura M.

    2016-09-01

    Full Text Available In the present work, barrier-biomimetic multilayer coatings were synthesized via sol-gel on the commercial Elektron 21 magnesium alloy, with potential interest in the fabrication of orthopaedic temporal implants. Sol-gel synthesis was carried out from a mixture of inorganic and organic precursors, TEOS and GPTMS. Two different sols were prepared: sols employed for the design of barrier coatings (named GT which function were to protect the magnesium alloy against corrosion; and sols containing additionally calcium nitrate (named GTCa, in different concentrations, for the design of the biomimetic coatings, which were deposited over the GT coating. The results confirmed that the GT coatings enhanced the corrosion resistance of the base alloy in Hank solution, reducing the corrosion current density in about two orders of magnitude. Further, the presence of Ca(II in GTCa coatings promoted the formation of discontinuous film of hydroxyapatite on the surface, indicating that those coatings exhibit bioactive properties.En el presente estudio se sintetizaron recubrimientos híbridos multicapa barrera-biomimético vía sol-gel sobre la aleación de magnesio Elektron 21, de potencial aplicación en el diseño de implantes ortopédicos de uso temporal. Para la síntesis sol-gel se empleó mezclas de los precursores de películas inorgánicas, TEOS, orgánicas y GPTMS. Se prepararon soles para el desarrollo del recubrimiento barrera frente al proceso de corrosión (soles GT; y soles con incorporación de nitrato de calcio en diferentes concentraciones (soles GTCa, para el desarrollo de los recubrimientos biomiméticos que fueron depositados sobre el recubrimiento GT. Los resultados obtenidos revelaron que el recubrimiento GT incrementó la resistencia a la corrosión de la aleación en solución Hank, reduciendo la densidad de corriente de corrosión alrededor de dos órdenes de magnitud. Asimismo, la incorporación de Ca(II a los recubrimientos GTCa

  12. Enhanced 3  μm luminescence properties based on effective energy transfer Yb3+ : 2F5/2→Dy3+ : 6H5/2 in fluoaluminate glass modified by TeO2.

    Science.gov (United States)

    Qi, Fangwei; Huang, Feifei; Wang, Tao; Tian, Ying; Lei, Ruoshan; Ye, Renguang; Zhang, Junjie; Zhang, Long; Xu, Shiqing

    2017-11-01

    Enhanced 3 μm luminescence of Dy 3+ based on the effective process of Yb 3+ :F 5/2 2→Dy 3+ :H 5/2 6 with a higher energy transfer coefficient of 7.36×10 -39   cm 6 /s in fluoaluminate glass modified by TeO 2 was obtained. The energy transfer efficiency from Yb 3+ to Dy 3+ in Dy 3+ /Yb 3+ codoped glass was as high as 80%, indicating the effective energy transfer of Yb 3+ . The higher temperature of the glass transition (T g ) and larger characteristic temperatures (ΔT,K gl ) revealed better thermal properties of the prepared glasses compared with the traditional fluoaluminate glasses, which is of great benefit to fiber drawing. The lower hydroxyl content (15.7 ppm) indicated better fluorescence properties of the glass. It was noted that the longer lifetime of 572 μs and higher emission cross section of 5.22×10 -21   cm 2 along with the bandwidth of 245 nm around 3 μm proved potential applications in mid-IR laser materials of the present glass.

  13. USA ajakirjaniku teos paljastab CIA nõrkusi / Neeme Raud

    Index Scriptorium Estoniae

    Raud, Neeme, 1969-

    2007-01-01

    Ilmunud ka: Postimees : na russkom jazõke, 30. juuli 2007, lk. 6. New York Timesi ajakirjanik Tim Weiner annab oma äsjailmunud raamatus "Legacy of ashes: the history of the USA" põhjaliku ülevaate CIA ajaloost. Lisa: CIA läbikukkumiste jada

  14. Dry Distillation of Radioiodine from TeO2 Targets

    Directory of Open Access Journals (Sweden)

    Jacek Koziorowski

    2013-10-01

    Full Text Available As medical cyclotrons are becoming more abundant, 123I and 124I are getting more attention as alternatives to 131I for diagnostics of thyroid disease. Both 123I and 124I provide better diagnostics, deliver less dose to patients and both reduce the risk of thyroid stunning, facilitating subsequent therapy. Dry distillation of radioiodine from tellurium dioxide targets has become the standard approach to producing these radioiodines. Setting up such a production of radioiodine is associated with a lengthy optimization of the process and for this purpose natural tellurium is often used for economical reasons. In this paper, the distillation parameters are scrutinized to ensure optimal distillation temperature, in order to minimize time spent and prevent loss of expensive target material. It is further demonstrated how the individual iodine isotopes, produced from proton bombardment of natTe, will diffuse out of the target in a time dependent ratio. We believe the effect is due to the isotopes having their maximum cross section at different energies. The individual isotopes produced will thus have their highest concentration at different depths in the target. This results in individual mean diffusion lengths and diffusion times for the different isotopes.

  15. Teo-iconology of sacrificial power among the Moche

    OpenAIRE

    Chaparro Amaya, Adolfo

    2011-01-01

    Partiendo de las evidencias icónicas del rasgo predatorio y sus equivalentes narrativos presentes en diferentes piezas de la cultura mochica, el texto busca establecer (i) una metodología de aproximación al sacrificio caníbal que tenga en cuenta diversas formas icónicas de ‹escritura›, y (ii) una explicación so-ciocósmica de la política sacrificial. Al articular lo escritural y lo político, es posible aportar una nueva perspectiva a la rica discusión que sobre las relaciones entre...

  16. Language learning through storying on iTEO

    OpenAIRE

    Kirsch, Claudine; Di Letizia, Laurence

    2015-01-01

    Luxembourg is a trilingual country and the EU state with the highest percentage of foreign residents. Currently, 62% of nursery children do not speak Luxembourgish as their first language. They learn Luxembourgish in the nursery aged 4. The project “TEO” aims at developing multilingual oracies through collaborative storytelling in nursery and lower primary schools. “Storying” is a leading activity because it activates cognitive, social and emotional processes. It capitalizes on children’s...

  17. Uus vaimulik teos Arvo Pärdilt / Priit Kuusk

    Index Scriptorium Estoniae

    Kuusk, Priit, 1938-

    2003-01-01

    Arvo Pärdi teose "Il principio" maailmaesiettekandest Austrias Grazi Herz-Jesu kirikus. Heliplaadipreemiate Classical Brit Awards jagamisel Londoni Royal Albert Hallis võitis preemia Arvo Pärt plaadiga "Orient & Occident", esitajad plaadil Rootsi Raadio koor ja sümfooniaorkester Tõnu Kaljuste juhatusel

  18. Otsustava teo päev / Tiit Maksim

    Index Scriptorium Estoniae

    Maksim, Tiit, 1941-

    2005-01-01

    Tallinnas Harjumäe nõlval avati Vabaduse monumendi alge - Võrumaalt Urvaste vallast toodud põllukivi, millesse on raiutud "Siia rajatakse vabaduse monument. 29. X 2005", osales ka parlamendiliige, spiiker Ene Ergma

  19. Teo-iconología del poder sacrificial entre los mochica Teo-iconology of sacrificial power among the Moche

    Directory of Open Access Journals (Sweden)

    Adolfo Chaparro Amaya

    2011-12-01

    Full Text Available Partiendo de las evidencias icónicas del rasgo predatorio y sus equivalentes narrativos presentes en diferentes piezas de la cultura mochica, el texto busca establecer (i una metodología de aproximación al sacrificio caníbal que tenga en cuenta diversas formas icónicas de ‹escritura›, y (ii una explicación so-ciocósmica de la política sacrificial. Al articular lo escritural y lo político, es posible aportar una nueva perspectiva a la rica discusión que sobre las relaciones entre canibalismo y poder han venido proponiendo los arqueólogos, los semióticos y los antropólogos de las culturas prehispánicas.Based on the iconographic evidences of predation and their narrative equivalents, present in different aspects of the Mochica culture, this essay seeks to establish (i a methodology for approaching the cannibal sacrifice taking into account different forms of iconic ‹writing›; and (ii establish a socio-cosmic explanation to sacrificial politics. By articulating these scriptural and political aspects, the paper will provide a new perspective to the rich discussion on the relationship between cannibalism and power that has been proposed by archaeologists, anthropologists and studies on the semiotic of Prehispanic cultures.

  20. Teo Krüüner: ranget lennukeeeldu ehk polnuks vaja / Teo Krüüner ; intervjueerinud Priit Simson

    Index Scriptorium Estoniae

    Krüüner, Teo, 1943-

    2010-01-01

    Intervjuu Eesti lennuväeakadeemia õppejõu, õhuväe endise ülemaga vulkaanilise tuhaga seotud riskist lennukitele, tuha erinevast mõjust eri lennukitele, ulatuslikust lennupiirangust Euroopas, Tu-154 tüüpi lennuki usaldusväärsusest

  1. Atuação fonoaudiológica na Unidade De Terapia Intensiva em bebê com síndrome de pterígeo poplíteo Speech-language therapy at the Neonatal Intensive Care Unit with a baby with popliteal pterygium syndrome

    Directory of Open Access Journals (Sweden)

    Susana Elena Delgado

    2009-01-01

    Full Text Available O objetivo deste estudo foi descrever a intervenção fonoaudiológica para a adequação da função alimentar por meio da avaliação e tratamento do sistema estomatognático e suas funções. O estudo foi feito a partir do relato de caso de um recém-nascido portador da Síndrome de Pterígio Poplíteo, que foi alimentado por sonda, atendido na Unidade de Tratamento Intensivo Neonatal. A avaliação fonoaudiológica apresentou os seguintes resultados: mandíbula retraída com pouca abertura, gengivas superiores e inferiores hipertróficas, palato com fissura pós-forame incisivo incompleta, reflexos orais de alimentação (busca, sucção, deglutição presentes e adequados; reflexos de defesa (mordida, gag anteriorizados e exacerbados. Apresentou pouca tolerância ao toque intra-oral. A sucção não nutritiva teve como resultado um número de sucções/pausas de 3:1, com ritmo presente, com força débil. Na sucção nutritiva, por meio da mamadeira, apresentou sucções/pausa de 5:1, com pausas longas. Foram observados sinais de estresse de alteração respiratória, estridor inspiratório leve, um episódio de engasgo e reflexo de gag anteriorizado e exacerbado, demonstrando hipersensibilidade oral em resposta ao bico convencional da mamadeira. Foram realizadas cinco sessões de intervenção fonoaudiológica, com orientações para a mãe e a equipe de enfermagem sobre postura, estimulação oral e uso de bico ortodôntico. O recém-nascido teve alta com via oral plena e com bom ganho de peso.The aim of this study was to describe the speech-language intervention for the adequacy of the alimentary function through assessment and treatment of the stomatognathic system and its functions. The study was carried out based on the case report of a newborn with popliteal pterygium syndrome, fed by tube while taken care of at the Neonatal Intensive Care Unit (NICU. The speech-language assessment presented the following results: retracted jaw with

  2. "Jutustus Liivimaast" - vähetuntud teos Liivimaa ajaloost / Janet Laidla

    Index Scriptorium Estoniae

    Laidla, Janet, 1982-

    2008-01-01

    Teose "An Account of Livonia : with a Relation of the Rise, Progress, and Decay of the Marian Teutonick Order" (London : Peter Buck, 1701) kirjeldus. Ülevaade seitsmeteistkümnest kirjast koosnevast ajalooteemalisest raamatust. Teose autorlusest. Olulisemad on teoses Kuramaad kirjeldavad osad, kuna tõenäoliselt oli autor Kuramaa vabahärra Karl Johann von Blomberg

  3. Trafalgar Square'ile järjekordne teos valitud / Rael Artel

    Index Scriptorium Estoniae

    Artel, Rael, 1980-

    2004-01-01

    Järgmisel kevadel paigaldatakse Trafalgar Square'ile 18 kuuks Marc Quinni 4,5 m kõrgune valgest marmorist kuju "Alison Lapper Pregnant". A. Lapper (sünd. 1965) on raske füüsilise väärarenguga kunstnik. Seejärel paigaldatakse väljakule teine finaali jõudnud skulptuur - sakslase Thomas Schütte'i "Hotel for the Birds"

  4. Projekt EUth, platvorm OPIN ja noorte e-osalemine / Teo Gregov, Kerstin Franzi ; kommenteerinud Ivo Visak

    Index Scriptorium Estoniae

    Gregov, Teo

    2016-01-01

    Projekti EUth eesmärk on suurendada noorte huvi ja aktiivset osalemist nii kohalikes kui ka Euroopa poliitilistes institutsioonides ja organisatsioonides. Projekti tulemusena valmis veebiplatvorm OPIN (www.opin.me), mis aitab projekte kavandada ja hallata

  5. A kinetic study of drying of TEOS-derived gels under nearly isothermal conditions

    Directory of Open Access Journals (Sweden)

    Donatti Dario A.

    1999-01-01

    Full Text Available The drying of wet Tetraethoxysilane-derived gels was studied by means of thermogravimetric analysis as a function of the time, from the instant when the samples were placed into a pre-heated oven, kept at 70, 83 and 100 °C. The precursor sol of the gel was obtained by sono-hydrolysis of the Tetraethoxysilane under acid condition and the final [Water]/[Tetraethoxysilane] molar ratio was adjusted to 30. The wet gels were cylindrical (2.5 cm height and 1.2 cm diameter after 30 days of aging at 30 °C in a hermetically sealed container. The changes in volume and weight during drying are compatible with a mechanism controlled by evaporation from a flat liquid-vapour interface at the surface of the body and contraction of the gel by capillary forces, together with structural changes induced by polycondensation, which partially account for the irreversible shrinkage of the gel. The employed thermogravimetric method does not permit to unequivocally follow the small and slow final loss of weight associated to the falling rate periods.

  6. Kunstnikuraamat - teos või dokument? / Alissa Nirgi, Marge Monko, Anu Vahtra ; intervjueerinud Laura Kuusk

    Index Scriptorium Estoniae

    Nirgi, Alissa, 1993-

    2016-01-01

    Alissa Nirgi, Marge Monko ja Anu Vahtra mõtteid, kuidas nende viimaste aastate kunstiprojektid raamatukaante vahele jõudsid. Alissa Nirgi fotoseeriast ja raamatust "Kaspar istub". Marge Monko fototööst "Kümme pärast kümmet", performance'ist ja raamatust "Don't wind it up, turn it on". Anu Vahtra installatsioonidest ja raamatust "Untitled"

  7. Masskuriteod : väike teosüü ja suur ohtlikkus / Ken-Marti Vaher

    Index Scriptorium Estoniae

    Vaher, Ken-Marti, 1974-

    2008-01-01

    Broken window'st ehk katkise akna teooriast. Juhtimisvõimekuse tähtsusest kriminaalpoliitikas ning olulise mõjuga pisirikkumistest ja nende vastu võitlemisest Eestis. Artikkel põhineb ettekandel, mille autor pidas Jaan Sootaki 60. juubeli puhul toimunud teaduskonverentsil 19. sept. 2008 Tartus

  8. Effect of gamma radiation on electrical and optical properties of (TeO2)

    Indian Academy of Sciences (India)

    Employing dose dependence of the current, some real-time gamma radiation dosimeters have been prepared, which ... are on world over to investigate the influence of gamma radi- ... Employing thermal evaporation in a vacuum, thin films of.

  9. Muusikamaailm : Wien Modern 2000. Muusikateater Huddersfieldis. Sibeliuse konkurss Helsingis. Penderecki uus teos Tokyos / Priit Kuusk

    Index Scriptorium Estoniae

    Kuusk, Priit, 1938-

    2000-01-01

    Nüüdismuusikafestivalist "Wien Modern" 28. okt.-26. nov. Muusikalavastustest Huddersfieldi kaasaegse muusika festivalil. VIII Sibeliuse nim. rahvusvahelisest viiuldajate konkursist. 30. nov. toimus Tokyos K. Penderecki teose "Concerto grosso per tre violoncelli ed orchestra"

  10. Nonlinear optical properties of TeO$_2$ crystalline phases from first principles

    OpenAIRE

    Berkaine, Nabil; Orhan, Emmanuelle; Masson, Olivier; Thomas, Philippe; Junquera, Javier

    2010-01-01

    We have computed second and third nonlinear optical susceptibilities of two crystalline bulk tellurium oxide polymorphs: $\\alpha$-TeO$_{2}$ (the most stable crystalline bulk phase) and $\\gamma$-TeO$_{2}$ (the crystalline phase that ressembles the more to the glass phase. Third order nonlinear susceptibilities of the crystalline phases are two orders of magnitude larger than $\\alpha$-SiO$_{2}$ cristoballite, thus extending the experimental observations on glasses to the case of crystalline com...

  11. Intense green emission from Tb3+- doped Teo2-Wo3-Geo2 glasses

    Science.gov (United States)

    Subrahmanyam, Tallam; Gopal, Kotalo Rama; Suvarna, Reniguntla Padma; Jamalaiah, Bungala Chinna

    2018-04-01

    Tb3+ -doped oxyfluoro tellurite (TWGTb) glasses were prepared by conventional melt quenching technique. The Judd-Ofelt theory has been applied to evaluate the Ωλ (λ=2,4,6) intensity parameters. The TWGTb glasses exhibit 5D3 → 7F5-3 and 5D4 → 7F6-0 transitions when excited at 316 nm wavelength. The variation of intensity of 5D4 → 7F5 (Green) and 5D3 → 7F4 (Blue) transitions and the green to blue (IG/IB) intensity ratios were studied as a function of Tb3+ ions concentration. The laser characteristic parameters such as effective bandwidth (Δλeff), stimulated emission cross-section (σe), gain bandwidth (σe×Δλeff) and optical gain (σe×τR) were determined using the emission spectra and radiative parameters. The luminescence decay profiles exhibit single-exponential nature for all the samples. Based on the experimental results we suggest that the 1.0 mol% of Tb3+-doped TWGTb glass could be the suitable laser host materials to emit intense green luminescence at 545 nm.

  12. On the optical band gap in certain ternary phosphate and TeO2 based glasses

    Czech Academy of Sciences Publication Activity Database

    Tichá, H.; Tichý, Ladislav

    2011-01-01

    Roč. 5, č. 12 (2011), s. 1277-1281 ISSN 1842-6573 Institutional research plan: CEZ:AV0Z40500505 Keywords : optical band gap * heavy metal oxide glasses Subject RIV: CA - Inorganic Chemistry Impact factor: 0.304, year: 2011 http://oam-rc.inoe.ro/index.php?option=magazine&op=view&idu=1737&catid=69

  13. Uudised : EFK ja TKO kontserdireis. Ajakiri Tempo Veljo Tormisest. Maestro Teo Maiste CD / Allan Vurma

    Index Scriptorium Estoniae

    Vurma, Allan, 1955-

    2000-01-01

    EFK ja TKO kontsertreisist USAsse ja Kanadasse 4.-23. veebr. Inglise kaasaegse muusika kvartalikiri "Tempo" jaanuarinumber (nr. 211) avaldas ulatusliku artikli V. Tormisest. 3. veebr. tähistati Estonia talveaias järjekordse CD ilmumist sarjas "Estonia väljapaistvaid lauljaid", peakangelaseks T. Maiste

  14. Evaluation of the elastic properties of monovalent oxides using TeO 2

    Indian Academy of Sciences (India)

    Faculty of Science, Department of Physics, Zagazig University, Zagazig, Egypt; Faculty of Science, Department of Physics, King Khalid University, Abha 9004, Saudi Arabia; Faculty of Science, Department of Physics, Al-Azhar University, Nasr City 11884, Egypt; Faculty of Science, Department of Physics, Al-Azhar University, ...

  15. Endale lisatasu maksnud Seeder vallandas sama teo eest alluva / Mehis Tulk, Andres Sepp

    Index Scriptorium Estoniae

    Tulk, Mehis, 1967-

    2008-01-01

    Taimetoodangu Inspektsiooni peadirektori kohalt vallandatud Mart Mäeker käib kohut põllumajandusministeeriumiga ja on hämmeldunud ministeeriumis valitsevast topeltmoraalist tulemustasude määramisel ja põllumajandusminister Helir-Valdor Seederi käitumisest. Vt. samas: Kaire Uusen. Ministrite suud jäid lukku

  16. Entre dos mundos: los grabados al aire libre de Pena Bicuda de Loureiro (Teo, Galicia, España = Between two worlds: prehistoric open-air petroglyphs from Pena Bicuda de Loureiro (Teo, Galicia, Spain

    Directory of Open Access Journals (Sweden)

    Ramón Fábregas Valcarce

    2015-11-01

    Full Text Available Abordamos el estudio de un interesante petroglifo prehistórico registrado recientemente, que muestra las habituales combinaciones circulares pero también motivos menos usuales como espirales o un posible ídolo. Por otra parte, no es frecuente que una estación rupestre, situada lejos de la costa, posea un número relativamente alto de representaciones zoomorfas (en su mayoría ciervos, algunas de ellas aparentemente en estrecha asociación con el motivo idoliforme. Hemos hecho uso de la cartografía LIDAR y aplicamos análisis SIG para determinar los patrones espaciales básicos de ubicación de los petroglifos y su eventual relación con otros monumentos cercanos, específicamente túmulos.We deal with an interesting prehistoric petroglyph recently recorded, displaying the common circular combinations and also less usual motifs such as spirals or a possible idol. Otherwise, it is by no means frequent that a decorated stone, located away from the coastline, should show a relatively high number of zoomorphic representations (mostly deer, a number of them apparently in close association with the idol-like motif. We have made use of LIDAR cartography and applied GIS techniques to ascertain the basic spatial patterns of location of the petroglyph and its eventual relationship with other monuments found nearby, namely funerary mounds.

  17. Effect of F- ions on physical and spectroscopic properties of Yb3+-doped TeO2-based glasses

    International Nuclear Information System (INIS)

    Wang Guonian; Dai Shixun; Zhang Junjie; Xu Shiqing; Hu Lili; Jiang Zhonghong

    2005-01-01

    The effects of F - ions on physical and spectroscopic properties of the Yb 3+ in tellurite glass system are investigated. The results show that the glass system takes on good thermal stability with the content of ZnF 2 lower than 15 mol%, both the emission cross-section and the fluorescence lifetime of Yb 3+ ions increase evidently which indicate that such oxyfluoride tellurite glass system is a promising laser host matrix for high power generation. FT-IR spectra were used to analyze the effect of F- ions on the structure of tellurite glasses and OH - groups in this glass system. Analysis demonstrates that addition of fluoride decreases the symmetry of the structure of tellurite glasses which increases the emission cross-section and removes the OH - groups, and which improves the measured fluorescence lifetime of Yb 3+ ions

  18. Baltisakslase romaan : teos ja autor / Ljubov Kisseljova ; venekeelsest käsikirjast tõlkinud Mall Jõgi

    Index Scriptorium Estoniae

    Kisseljova, Ljubov, 1950-

    2016-01-01

    Analüüsitakse Eestist pärit parun Karl Georg Woldemar Friedrich von Roseni almanahhis "Altsiona" 1831. aastal ilmunud väikest romaani "Constantin Loeven. (Minu mälestustest)". Romaanis on oluline 19. sajandi alguse kreeklaste vabadusvõitluse kontekst

  19. Reinforced Carbon Carbon (RCC) oxidation resistant material samples - Baseline coated, and baseline coated with tetraethyl orthosilicate (TEOS) impregnation

    Science.gov (United States)

    Gantz, E. E.

    1977-01-01

    Reinforced carbon-carbon material specimens were machined from 19 and 33 ply flat panels which were fabricated and processed in accordance with the specifications and procedures accepted for the fabrication and processing of the leading edge structural subsystem (LESS) elements for the space shuttle orbiter. The specimens were then baseline coated and tetraethyl orthosilicate impregnated, as applicable, in accordance with the procedures and requirements of the appropriate LESS production specifications. Three heater bars were ATJ graphite silicon carbide coated with the Vought 'pack cementation' coating process, and three were stackpole grade 2020 graphite silicon carbide coated with the chemical vapor deposition process utilized by Vought in coating the LESS shell development program entry heater elements. Nondestructive test results are reported.

  20. Uudised : Ernesaksa auhind ning stipendiumid. Arvo Pärdi uus teos Roomas. Paavo Järvi Euroopas / Ilmar Moss

    Index Scriptorium Estoniae

    Moss, Ilmar

    2000-01-01

    4. dets. toimus Kuusalus G.Ernesaksa mälestuskontsert, kus anti üle stipendiumid ja Ernesaksa nim. auhind. 19. nov. toimus Roomas A.Pärdi teose "Cecilia, vergine romana" esiettekanne. P.Järvi kontsertidest detsembris Euroopas

  1. ISLAM, EKSKOMUNIKASI, DAN PERSOALAN PENYESATAN: Kajian Teo-Sosio-Analisis atas Vonis Bid‘ah, Riddah, dan Kufr

    Directory of Open Access Journals (Sweden)

    Yusuf Hanafi

    2007-12-01

    Full Text Available The Muslims’ responses toward and understanding about the texts of Qur’an and hadîts—usually named as living Qur’an/tafsîr and living hadîts/sunnah—are of the objects of Islamic studies. Such responses include the Muslims’ reception and their interpretations toward certain texts and exegete found in the Muslims’ daily life, such as traditionalizing of recitation of certain chapters and verses of Qur’an in some social religious ceremonies and celebration. The social reception of the interpretations take form of either small or large scale of institutionalization.The Muslims’ responses toward and understanding about the texts of Qur’an and hadîts and their receptions do not cause any problems until the emergence of authorities in the Muslims’ communities that accuse them as heresy (bid‘ah, apostasy (riddah, and infidelity (kufr. This becomes the starting point of perverting and excommunication phenomena in Islam. This article is aimed at elaborating that problem and analyzing the phenomena through Theo-social-analysis.

  2. Critical V2O5/TeO2 Ratio Inducing Abrupt Property Changes in Vanadium Tellurite Glasses.

    Science.gov (United States)

    Kjeldsen, Jonas; Rodrigues, Ana C M; Mossin, Susanne; Yue, Yuanzheng

    2014-12-26

    Transition metal containing glasses have unique electrical properties and are therefore often used for electrochemical applications, such as in batteries. Among oxide glasses, vanadium tellurite glasses exhibit the highest electronic conductivity and thus the high potential for applications. In this work, we investigate how the dynamic and physical properties vary with composition in the vanadium tellurite system. The results show that there exists a critical V(2)O(5) concentration of 45 mol %, above which the local structure is subjected to a drastic change with increasing V(2)O(5), leading to abrupt changes in both hardness and liquid fragility. Electronic conductivity does not follow the expected correlation to the valence state of the vanadium as predicted by the Mott-Austin equation but shows a linear correlation to the mean distance between vanadium ions. These findings could contribute to designing optimum vanadium tellurite compositions for electrochemical devices. The work gives insight into the mechanism of electron conduction in the vanadium tellurite systems.

  3. Thermal properties and optical transition probabilities of Tm3 + doped TeO2-WO3 glass.

    Science.gov (United States)

    Cenk, S; Demirata, B; Oveçoglu, M L; Ozen, G

    2001-10-01

    Glasses with the composition of (1 - x)TeO2 + (x)WO3, where x = 0.15, 0.25 and 0.3 were prepared and, their thermal and absorption measurements were carried out. Differential thermal analysis (DTA) curves taken in the 23-600 degrees C temperature range with a heating rate of 10 degrees C/min reveal a change in the value of the glass transition temperature, Tg, while crystallization was not observed for the glasses containing a WO3 content of more than 15 mol%. All the glasses were found to be moisture-resistant. The absorption bands corresponding to the absorption of the 1G4, 3F2, 3F3 and 3F4, 3H5 and 3H4 levels from the 3H6 ground level of the Tm3+ ion were observed in the optical absorption spectra. Integrated absorption cross-sections of each band except that of 3H5 level was found to vary with the glass composition. Judd-Ofelt analysis was carried out for the samples doped with 1.0 mol% Tm2O3. The omega2 parameter shows the strongest dependence on the host composition and it increases with the increasing WO3 amount. The value of omega4 increases rather slowly while the value of omega6 is practically independent of the composition. The strong dependence of the parameter omega2 indicates that this parameter is related to the structural change and the symmetry of the local environment of the Tm3+ ions in this glass.

  4. Eesti kalleim müügil maal on Vene kunstniku neli miljonit maksev teos / Nele Laanemäe

    Index Scriptorium Estoniae

    Laanemäe, Nele

    2004-01-01

    Tallinna kunstisalongides olevatest hinnalistest kunstiteostest. Oma rariteete tutvustavad Shifara galerii president Shifara Hindrekson, galerii Rios omanik Elena Tsuhkna, Galerii 36 omanik Rita Parel, Allee Kunstisalongi omanik Juhan Kohal. Arkhip Kuindzhi, Johann Köleri, Tõnis Grenzsteini, Johannes Võerahansu väärtuslikest maalidest

  5. Nanosized Thin SnO2 Layers Doped with Te and TeO2 as Room Temperature Humidity Sensors

    Directory of Open Access Journals (Sweden)

    Biliana Georgieva

    2014-05-01

    Full Text Available In this paper the humidity sensing properties of layers prepared by a new method for obtaining doped tin oxide are studied. Different techniques—SEM, EDS in SEM, TEM, SAED, AES and electrical measurements—are used for detailed characterization of the thin layers. The as-deposited layers are amorphous with great specific area and low density. They are built up of a fine grained matrix, consisting of Sn- and Te-oxides, and a nanosized dispersed phase of Te, Sn and/or SnTe. The chemical composition of both the matrix and the nanosized particles depends on the ratio RSn/Te and the evaporation conditions. It is shown that as-deposited layers with RSn/Te ranging from 0.4 to 0.9 exhibit excellent characteristics as humidity sensors operating at room temperature—very high sensitivity, good selectivity, fast response and short recovery period. Ageing tests have shown that the layers possess good long-term stability. Results obtained regarding the type of the water adsorption on the layers’ surface help better understand the relation between preparation conditions, structure, composition and humidity sensing properties.

  6. Jaani kirik seljatas aasta teo konkursil hansapäevad / Mari-Liis Hüvato, Martin Shmutov

    Index Scriptorium Estoniae

    Hüvato, Mari-Liis

    2005-01-01

    Tartlased ja Postimehe lugejad tunnistasid Tartu 2005. aasta väärikaimaks teoks Jaani kiriku taastamise, kommenteerivad Juhani Jaeger, Toomas Peterson, Reet Mägi. Loetletud konkursil osalenud Tartu aasta teod 2005 ja varasemad aasta teod

  7. Photoluminescence properties of TeO_2-WO_3-ZrO_2-Dy_2O_3 glasses for γ-ray detection and applications

    International Nuclear Information System (INIS)

    Rajeswara Rao, V.; Lakshmi Devi, L.; Venkataiah, G.; Jayasankar, C.K.

    2016-01-01

    Now-a-days nuclear radiation detection is constantly becoming very important to protect environment for healthy, peaceful and happy life. Conventional scintillator based γ-ray detectors use single crystal materials such as NaI:Ti and LaBr_3:Ce which provide excellent radiation detection properties, but suffer from their environment-related fluctuation, high cost and size limitation. The use of glasses for the detection of ionizing radiation has the advantages of low-cost, simple processing, high sensitivity and can be operated at room temperature

  8. Endovascular treatment of complex traumatic lesions of the infrapopliteal segment Tratamento endovascular de lesões traumáticas complexas do segmento infrapoplíteo

    Directory of Open Access Journals (Sweden)

    Roberta C. A. Campos

    2009-06-01

    Full Text Available The occurrence of vascular trauma due to a range of causes has increased considerably. In this setting, endovascular repair has arisen as a new and less invasive approach. We report the case of three patients with lesions of below-knee vessels that were treated by endovascular procedures.A ocorrência de trauma vascular decorrente de diversas causas aumentou consideravelmente. Nesse contexto, o tratamento endovascular surge como um método novo e menos invasivo. Relatamos o caso de três pacientes com lesões abaixo do joelho que foram tratadas por procedimentos endovasculares.

  9. Electronic conductivity in glasses of the TeO sub 2 -V sub 2 O sub 5 -MoO sub 3 system

    Energy Technology Data Exchange (ETDEWEB)

    Lebrun, N.; Levy, M; Souquet, J.L. (URA D1213-E.N.S.E.E.G., Saint Martin d' Heres (France). Laboratoire d' Ionique et d' Electrochimie du Solide)

    1990-08-01

    Conductivity and redox potential on glasses of the TeO{sub 2}-V{sub 2}O{sub 5}-MoO{sub 3} system have been measured. For temperatures between 20 to 200 pC, the electronic conductivity proceed by an activated mechanism. Variations of the pre-exponential factor interpreted by the small polaron theory indicate that only the vanadium ions are involved in the conduction mechanism. Cyclic voltamperometry measurements performed on TeO{sub 2}V{sub 2}O{sub 4}-MoO{sub 3} glasses as working electrode show that at 1 V difference between the V{sup +V}/V{sup +IV} and Mo{sup +I}/Mo{sup +V} redox potentials exists in the glassy material. This correspondend to an energy gap which may be to large to allow the electron transition from vanadium to molybdenum ions. (author). 13 refs.; 4 figs.; 1 tab.

  10. Recommendations for Risk Categorization and Prophylaxis of Invasive Fungal Diseases in Hematological Malignancies: A Critical Review of Evidence and Expert Opinion (TEO-4

    Directory of Open Access Journals (Sweden)

    Can Boğa

    2015-06-01

    Full Text Available This is the last of a series of articles on invasive fungal infections prepared by opinion leaders in Turkey. The aim of these articles is to guide clinicians in managing invasive fungal diseases in hematological malignancies and stem cell transplantation based on the available best evidence in this field. The previous articles summarized the diagnosis and treatment of invasive fungal disease and this article aims to explain the risk categorization and guide the antifungal prophylaxis in invasive fungal disease.

  11. Optical properties of Sm3+ -doped TeO2sbnd WO3sbnd GeO2 glasses for solid state lasers

    Science.gov (United States)

    Subrahmanyam, T.; Gopal, K. Rama; Suvarna, R. Padma; Jamalaiah, B. Chinna; Rao, Ch Srinivasa

    2018-03-01

    Sm3+ -doped oxyfluoride tellurite-tungsten (TWGSm) glasses were prepared by conventional melt quenching method. The optical properties were investigated through photoluminescence excitation, emission and luminescence decay analysis. The optical band gap energy was determined as ∼3.425 eV for 1.0 mol% of Sm3+ -doped TWGSm glass. Upon 404 nm excitation, the TWGSm glasses emit luminescence through 4G5/2 → 6H5/2 (563 nm), 4G5/2 → 6H7/2 (600 nm), 4G5/2 → 6H9/2 (645 nm) and 4G5/2 → 6H11/2 (705 nm) transitions. The Judd-Ofelt analysis was performed using absorption spectrum and obtained radiative parameters were used to estimate the laser characteristics of present glasses. The concentration of Sm3+ has been optimized as 1.0 mol% for efficient luminescence. The luminescence decay of 4G5/2 emission level was studied by monitoring the emission and excitation wavelengths at 600 and 404 nm, respectively. The experimental lifetime of 4G5/2 level was decrease with increase of Sm3+ concentration. The 1.0 mol% of Sm3+ -doped TWGSm glass could be the best choice for solid state visible lasers to emit orange luminescence.

  12. Nonlinear optical properties of TeO2-P2 O5- ZnO-LiNbO3 glass doped with Er3+ ions

    Science.gov (United States)

    Miedzinski, R.; Fuks-Janczarek, I.; El Sayed Said, Y.

    2016-10-01

    A series of lithium niobate LiNbO3 (LN) single crystals doped with Er3+ were grown under the same conditions by melt-quenching method. The distribution coefficients of rare-earth (RE) elements in the "crystal-melt" system of LN were determined at the beginning of the crystal growth. Their dependence on the dopant concentration in melt for 0.4 and 0.8 wt % was investigated. The procedure is applied to RE-doped lithium niobate (LiNbO3), a material of great interest for optoelectronic applications. We have obtained the real χR(3) and imaginary parts χI(3) of the third-order, nonlinear optical susceptibility to the nonlinear refractive index n2 and the nonlinear absorption coefficient β that are valid for absorbing systems. We show that nonlinear refractive or absorptive effects are the consequence of the interplay between the real and imaginary parts of the third-order susceptibilities of the materials. The method for measuring non-linear absorption coefficients and nonlinear refractive index based on well-known Z-scan is presented.

  13. Red luminescence from Eu3+-doped TeO2-WO3-GeO2 glasses for solid state lasers

    Science.gov (United States)

    Subrahmanyam, Tallam; Gopal, Kotalo Rama; Suvarna, Reniguntla Padma; Jamalaiah, Bungala Chinna

    2018-05-01

    Eu3+-doped oxyfluoro tellurite (TWGEu) glasses were prepared by conventional melt quenching method. The optical band gap energy and covalence between Eu3+ and O2-/F- ions were determined from optical absorption spectra. Using the 5D0 → 7F1,2,4 emission transitions, the Ω2 and Ω4 intensity parameters were determined. These intensity parameters were used to evaluate the radiative parameters such as emission probability rate (AR), luminescence branching ratio (βR) and radiative life time (τR) of 5D0 → 7FJ transitions. The laser characteristic parameters such as stimulated emission cross-section, gain bandwidth and quantum efficiency were determined. The luminescence decay profiles of 5D0 emission level were well fitted to single exponential function for all the concentrations. The experimental results show that the 0.5 mol% of Eu3+-doped TWGEu glass could be the best choice to design red laser sources.

  14. Variation of energy absorption and exposure buildup factors with incident photon energy and penetration depth for boro-tellurite (B2O3-TeO2) glasses

    Science.gov (United States)

    Sayyed, M. I.; Elhouichet, H.

    2017-01-01

    The gamma ray energy absorption (EABF) and exposure buildup factors (EBF) of (100-x)TeO2-xB2O3 glass systems (where x=5, 10, 15, 20, 22.5 and 25 mol%) have been calculated in the energy region 0.015-15 MeV up to a penetration depth of 40 mfp (mean free path). The five parameters (G-P) fitting method has been used to estimate both EABF and EBF values. Variations of EABF and EBF with incident photon energy and penetration depth have been studied. It was found that EABF and EBF values were higher in the intermediate energy region, for all the glass systems. Furthermore, boro-tellurite glass with 5 mol% B2O3, was found to present the lowest EABF and EBF values, hence it is superior gamma-ray shielding material. The results indicate that the boro-tellurite glasses can be used as radiation shielding materials.

  15. Thermal characteristics, Raman spectra, optical and structural properties of TiO2-Bi2O3-B2O3-TeO2 glasses

    Science.gov (United States)

    Gupta, Nupur; Khanna, Atul; Gonzàlez, Fernando; Iordanova, Reni

    2017-05-01

    Tellurite and borotellurite glasses containing Bi2O3 and TiO2 were prepared and structure-property correlations were carried out by density measurements, X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Raman and UV-visible spectroscopy. Titanium tellurite glasses require high melt-cooling rates and were fabricated by splat quenching. On adding B2O3, the glass forming ability (GFA) enhances, and glasses could be synthesized at lower quenching rates. The density of glasses shows a direct correlation with molecular mass of the constituents. UV-visible studies were used to determine the optical band gap and refractive index. Raman studies found that the co-ordination number of tellurium ions with oxygen (NTe-O) decreases with the increase in B2O3 as well as Bi2O3 content while, TiO2 produce only a small decrease in NTe-O, which explains the lower GFA of titanium tellurite glasses that do not contain Bi2O3 and B2O3. DSC studies show that the glass transition temperature (Tg) increases with B2O3 and TiO2 concentrations and that Tg correlates well with bond enthalpy of the metal oxides.

  16. Luminescent properties of Tb3+- doped TeO2-WO3-GeO2 glasses for green laser applications

    Science.gov (United States)

    Subrahmanyam, T.; Rama Gopal, K.; Padma Suvarna, R.; Jamalaiah, B. C.; Vijaya Kumar, M. V.

    2018-06-01

    Different concentrations of Tb3+ -doped oxyfluoro tellurite (TWGTb) glasses were prepared by conventional melt quenching technique and characterized for green laser applications. The Judd-Ofelt theory was applied to evaluate various spectroscopic and radiative parameters. The TWGTb glasses exhibit 5D3 → 7F5-3 and 5D4 → 7F6-0 transitions when excited at 316 nm radiation. The variation of intensity of 5D4 → 7F5 (Green) and 5D3 → 7F4 (Blue) transitions and the green to blue (IG/IB) intensity ratios were studied as a function of Tb3+ ions concentration. The laser characteristic parameters such as effective bandwidth (Δλeff), stimulated emission cross-section (σe), gain bandwidth (σe × Δλeff) and optical gain (σe × τR) were determined using the three phenomenological Judd-Ofelt intensity parameters. The fluorescence decay profiles of 5D4 metastable level exhibit single-exponential nature for all the samples. Based on the experimental results we suggest that the 1.0 mol% of Tb3+ -doped TWGTb glass could be a suitable laser host material to emit intense green luminescence at 545 nm.

  17. Enhancement of luminescence properties in Er3+ doped TeO2-Na2O-PbX (X=O and F) ternary glasses.

    Science.gov (United States)

    Kumar, Kaushal; Rai, S B; Rai, D K

    2007-04-01

    An enhancement of luminescence properties in Er3+ doped ternary glasses is observed on the addition of PbO/PbF2. The infrared to visible upconversion emission bands are observed at 410, 525, 550 and 658 nm, due to the 2H9/2-->4I15/2, 2H11/2-->4I15/2, 4S3/2-->4I15/2, 4F9/2-->4I15/2 transitions respectively, on excitation with 797 nm laser line. A detailed study reveals that the 2H9/2-->4I15/2 transition arises due to three step upconversion process while other transitions arise due to two step absorption. On excitation with 532 nm radiation, ultraviolet and violet upconversion bands centered at 380, 404, 410 and 475 nm wavelengths are observed along with one photon luminescence bands at 525, 550, 658 and 843 nm wavelengths. These bands are found due to the 4G11/2-->4I15/2, 2P3/2-->4I13/2, 2H9/2-->4I15/2, 2P3/2-->4I11/2, 2H11/2-->4I15/2, 4S3/2-->4I15/2, 4F9/2-->4I15/2 and 4S3/2-->4I13/2 transitions, respectively. Though incorporation of PbO and PbF2 both enhances fluorescence intensities however, PbF2 content has an important influence on upconversion luminescence emission. The incorporation of PbF2 enhances the red emission (658 nm) intensity by 1.5 times and the violet emission (410 nm) intensity by 2.0 times. A concentration dependence study of fluorescence reveals the rapid increase in the red (4F9/2-->4I15/2) emission intensity relative to the green (4S3/2-->4I15/2) emission with increase in the Er3+ ion concentration. This behaviour has been explained in terms of an energy transfer by relaxation between excited ions.

  18. Calculation and analysis of vibrational spectra of PbCl(2)-Sb(2)O(3)-TeO(2) glass from first principles

    Czech Academy of Sciences Publication Activity Database

    Macháček, J.; Kostka, Petr; Liška, M.; Zavadil, Jiří; Gedeon, O.

    2011-01-01

    Roč. 357, č. 14 (2011), s. 2562-2570 ISSN 0022-3093 R&D Projects: GA ČR GA104/08/0734; GA MPO 2A-1TP1/063 Institutional research plan: CEZ:AV0Z40320502; CEZ:AV0Z20670512 Keywords : vibrational spectrum * tellurite glass * ab initio molecular simulation Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass Impact factor: 1.537, year: 2011

  19. Preparation and optical characterization of PbCl(2)-Sb(2)O(3)-TeO(2) glasses doped with rare earth elements

    Czech Academy of Sciences Publication Activity Database

    Kostka, Petr; Zavadil, Jiří; Pedlíková, Jitka; Poulain, M.

    2011-01-01

    Roč. 208, č. 8 (2011), s. 1821-1826 ISSN 1862-6300 R&D Projects: GA ČR GA104/08/0734 Institutional research plan: CEZ:AV0Z40320502; CEZ:AV0Z20670512 Keywords : glass * heavy metal oxides * optical properties * photoluminescence Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass Impact factor: 1.463, year: 2011

  20. Recommendations for the Treatment of Invasive Fungal Infections in Hematological Malignancies: A Critical Review of Evidence and Turkish Expert Opinion (TEO-1

    Directory of Open Access Journals (Sweden)

    Hamdi Akan

    2014-06-01

    Full Text Available The introduction of novel antifungal agents for the treatment of invasive fungal disease in hematological malignancies and also changing treatment strategies have had a great impact in managing affected patients. The medical literature includes some important clinical studies that are being used as evidence for guidelines. The problem with these studies and the guidelines is that they are not very easy to interpret, they include controversial issues, and they are not easy to apply to every patient or country. This paper was designed to critically show the main problems associated with these approaches and provide important information that will help Turkish doctors to adopt them in daily clinical practice.

  1. Teo-odisea cantada: Vida e imaginario del creyente pentecostal a través de sus cánticos

    Directory of Open Access Journals (Sweden)

    Angélica Barrios

    2009-10-01

    Full Text Available The canticles called "coritos" belong to the set of elements that shape the liturgy pentecostal classic. As musical and poetical constructions they possess an anonymous authorship and represent the imaginary one of the religious collectivity of the first generations pentecostales of the country. In the intention of analyzing the elements imageneológicos that sublie in the content of his letters, we believe that the coritos are signs of a community profesante that it expresses his vital experiences and the relation with the divinity across a speech that it interprets, it reorders the experiences and elements of the memory, granting sense and identity to the religious group.

  2. USO DA eCG PARA FORMAÇÃO DO CORPO LÚTEO EQÜINO E PRODUÇÃO DE PROGESTERONA

    Directory of Open Access Journals (Sweden)

    Tiago Gomes RODRIGUES

    2015-12-01

    Full Text Available Este estudo foi conduzido com a finalidade de avaliar o uso da gonadotrofina coriônica eqüina (eCG logo após a ovulação de éguas com o objetivo avaliar a formação do corpo lúteo e produção de progesterona. Utilizou-se 50 éguas durante 2 estações de monta 2011/2012 e 2012/2013. Com auxílio da ultrassonografia as éguas foram monitoradas as características dos órgãos genitais durante o estro até o dia da ovulação (D0 e no diestro em D2, D4 e D8. O experimento foi dividido em 2 tratamentos: Tratamento I (n=25 – éguas com ovulação natural e tratamento II (n=25  – éguas com ovulação induzida. Verificada a ovulação, os tratamentos foram sub divididas em 5 grupos de 5 animais, obedecendo a administração do fármaco estudado (eCG, sendo GI: controle; GII: 250 UI eCG no DO; GIII: 250 UI eCG no DO + 250 UI eCG no D2; GIV: 500 UI no Do; e GV: 500 UI eCG no D0 + 500 UI no D2. Para a avaliação do efeito dose resposta do fármaco e influência do eCG sob a glândula luteínica, foram coletados os dados: tônus uterino, ecogenicidade e tamanho do corpo lúteo (CL e concentração de progesterona. Na análise estatística somente quando comparando o GV entre os dois tratamentos há diferença estatística para o D8 na concentração de progesterona. Portanto o uso da eCG no momento da ovulação, não produziu efeito significativo esperado, mas este trabalho inicial abre portas para novas investigações a respeito desta biomolécula, e que venha contribuir na biotecnologia reprodutiva equina.

  3. Paavo Järvi eesti muusikaga. Eesti oratooriumikoor Iisraelis. Sumera teos virtuoosses ettekandes. Väike ooper Peterburis. Olev Ehala EHLi esimeheks. "Talvepihu" taaselustab näärid. Respeito a Jobim. Tubina ühingus / Priit Kuusk

    Index Scriptorium Estoniae

    Kuusk, Priit, 1938-

    2002-01-01

    Paavo Järvi esinemistest mitmete orkestritega ja eesti muusikaga. Eesti oratooriumikoor reisib Iisraeli, et osaleda Israel New Opera projektis. Saksamaa ajalehtedes avaldati tunnustavat kriitikat Sumera teose virtuoosse ettekande kohta. 24. ئ 26. I viibis Peterburis lasteteater Väike Ooper. Eesti Heliloojate Liit valis oma esimeheks Olev Ehala. Estonia Seltsi Segakoor ja Saue Poistekoor alustavad talvemuusika kontsertide sarja "Talvepihu". Bossa Nova kuninga Antonio Carlos Jobimi 75. sünniaastapäevale pühendatud kontserdist "Respeito a Jobim". 5.II toimunud Eduard Tubina ühingu aastakoosolekust

  4. Investigation of radiation shielding properties for MeO-PbCl2-TeO2 (MeO = Bi2O3, MoO3, Sb2O3, WO3, ZnO) glasses

    Czech Academy of Sciences Publication Activity Database

    Sayyed, M.I.; Celikbilek Ersundu, M.; Ersundu, A.E.; Lakshminarayana, G.; Kostka, Petr

    2018-01-01

    Roč. 144, March 2018 (2018), s. 419-425 ISSN 0969-806X Institutional support: RVO:67985891 Keywords : tellurite glasses * XCOM * radiation shielding * mass attenuation coefficient * exposure buildup factor Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass Impact factor: 1.315, year: 2016

  5. PRODUÇÃO in vitro DE EMBRIÕES DE BOVINOS DA RAÇA NELORE ORIUNDOS DE OVÓCITOS DE OVÁRIOS COM E SEM CORPO LÚTEO

    Directory of Open Access Journals (Sweden)

    Cristiano Pereira Barbosa

    2013-03-01

    Full Text Available This study aimed to compare the quality and quantity of oocytes aspirated from ovaries containing or not corpus luteum (CL, the development of embryos, pregnancy rate and sex ratio among embryos after IVP in Nellore cows. Follicular aspirations were performed in both ovaries of 219 cows in 250 sections, and equally divided into five groups: G1 = pregnant, G2 = not pregnant, with CL and submitted to hormonal therapy with progestin+BE+PGF2µ; G3 = not pregnant, without CL and with the same treatment of G2; G4 = not pregnant, with the presence of CL and no treatment; G5 = not pregnant, without the presence of CL and no treatment. The statistical analysis was performed with analysis of variance (ANOVA and Tukey Test was applied to compare means at 5% significance level, by SISVAR program. For the comparison of sex ratio within and between groups, the multiple comparison test of proportions was used. The G4 produced higher mean of total aspirated oocytes than G2 and G3. Comparing the three groups with CL, G4 showed higher number of oocytes than G1 and G2 in both ovaries. The G2 presented more viable oocytes than G1 in the CL-containing ovary. The ovaries without CL showed better production in pregnant cows despite of viable oocytes (p0.05 when compared with ovaries presenting CL. Oocytes obtained from ovaries with CL resulted in better rates of embryo production. Pregnancy rates and sex ratio were similar among groups (p>0.05. The P4 concentration was different between groups, but it did not influence any variable. The use of hormonal treatment did not improve the results of any variable. Therefore, choosing Nellore donors for IVP programs depends on knowing each animal individually along the sections of OPU

  6. O USO DA ELETROESTIMULAÇÃO MUSCULAR COM CORRENTE DE MÉDIA FREQUÊNCIA ASSOCIADA AO EXERCÍCIO RESISTIDO NO MÚSCULO GLÚTEO MÁXIMO: ESTUDO DE CASO

    Directory of Open Access Journals (Sweden)

    Edilane Gonçalves MONÇÃO

    2015-12-01

    Full Text Available A partir do século XX as mulheres começaram a se preocupar mais com seu corpo, e procuram passar cada vez mais uma imagem de mulher feminina e atraente. A fisioterapia dermato – funcional é uma área dentro da fisioterapia que tem o objetivo de tratar das patologias estéticas, promovendo a essas mulheres um bem – estar e uma melhor qualidade de vida. A corrente russa associado a cinesioterapia, tem sido um recurso bastante utilizados para tratar a flacidez muscular e a hipotonia muscular, por produzir hipertrofia muscular e fortalecimento com resultados melhores e em pouco tempo. Este trabalho teve por objetivo analisar a efetividade da associação da corrente russa e do exercício resistido no musculo glúteo máximo. Caracterizado como sendo uma pesquisa experimental com uma voluntária com idade de 21 anos. A voluntária realizou 24 sessões por três vezes na semana em um período de dois meses, com duração média de quarenta minutos cada sessão. Foram analisadas a circunferência da região do quadril, e a qualidade da musculatura da região glútea, através do teste de pinçamento. Os resultados mostraram-se favoráveis ao uso da corrente russa associada a cinesioterapia na melhora da perimetria do quadril, causando um aumento de massa muscular e melhorando a flacidez muscular

  7. Solid state field-assisted diffusion silver diffusion in (TeO2)0.6(WO3)0.25(La2O3)0.05(Na2O)0.1 glass

    Czech Academy of Sciences Publication Activity Database

    Stepanov, B.; Wágner, T.; Lorinčík, Jan; Frumar, M.; Churbanov, M.; Chigirinsky, Y.

    2012-01-01

    Roč. 48, č. 6 (2012), s. 642-647 ISSN 0020-1685 Institutional support: RVO:67985882 Keywords : Tellurite glass * Solid state diffusion * Secondary Ion Mass Spectrometry Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.376, year: 2012

  8. Structure and optical properties of TeO2 center dot PbCl2 center dot PbF2 glasses doped with Pr and Er, prepared in Au or Pt crucibles

    Czech Academy of Sciences Publication Activity Database

    Trnovcová, V.; Kubliha, M.; Labas, V.; Kadleciková, M.; Pedlíková, Jitka; Greguš, J.; Slabeyclus, J.

    2012-01-01

    Roč. 14, 1-2 (2012), s. 77-83 ISSN 1454-4164 Institutional research plan: CEZ:AV0Z40320502 Keywords : Tellurite/lead chloride/lead fluoride glasses * Optical absorption * Photoluminescence Subject RIV: CA - Inorganic Chemistry Impact factor: 0.516, year: 2012

  9. On the structure and optical band gap in some (PbO)x(BaO)0.3-x(ZnO)0.1(TeO2)0.6 glasses

    Czech Academy of Sciences Publication Activity Database

    Tichá, H.; Tichý, Ladislav

    2015-01-01

    Roč. 9, 7-8 (2015), s. 951-955 ISSN 1842-6573 Institutional support: RVO:61389013 Keywords : optical properties * oxide glasses * Raman spectroscopy Subject RIV: CA - Inorganic Chemistry Impact factor: 0.412, year: 2015 http://oam-rc.inoe.ro/index.php?option=magazine&op=view&idu=2643&catid=91

  10. Electrical and dielectric properties of doped TeO2 center dot PbCl2 center dot PbF2 glasses, prepared in Au or Pt crucibles

    Czech Academy of Sciences Publication Activity Database

    Kubliha, M.; Trnovcová, V.; Labas, V.; Psota, J.; Pedlíková, Jitka; Podolinčiaková, J.

    2011-01-01

    Roč. 13, 11-12 (2011), s. 1493-1497 ISSN 1454-4164 Institutional research plan: CEZ:AV0Z40320502 Keywords : tellurite/lead chloride/lead fluoride glasses * electrical conductivity * TSDC * permittivity Subject RIV: CA - Inorganic Chemistry Impact factor: 0.457, year: 2011

  11. O método de leitura à primeira vista ao piano de Wilhelm Keilmann e sua fundamentação teórica

    Directory of Open Access Journals (Sweden)

    Maria Elisa Risarto

    2010-12-01

    Full Text Available This article aims at analyzing the foundation methods of teaching sight reading at the piano as proposed by Wilhelm Keilmann in his Introduction to Sight Reading at the Piano or other Keyboard Instrument. A bibliographic research identified the cognitive capabilities and skills that are involved in sight reading at the piano and other musical instruments, and verified the pedagogical effectiveness of this methodology.

  12. Planeering kui kaasaegne teos par excellence : kas tulevikku saab välja mõelda? = The plan as a contenporary work par excellence : can the future be made up? / Toomas Tammis

    Index Scriptorium Estoniae

    Tammis, Toomas, 1969-

    2011-01-01

    Tulevikku saab kavandada läbi visioonide, läbi erinevate erialade teadmistest kokku lõimunud loomingulise akti, mis ei saa kunagi olla liiga täpne. Planeering saab olla teatav süsteem, mis suudab lõputult produtseerida väikseid üsna täpselt koha- ja keskkonnatundlikke produkte, jäädes ise pidevasse loomisse ning pooleliolekusse, olles pidevas interaktsioonis ühiskonnaga viimast lõputult monitoorides ja muutes

  13. "Letjashtshi Kalevipoeg" i "Kakajushtshaja sobaka" - dva obraza narvskoi nedvizhimosti / Ilja Smirnov

    Index Scriptorium Estoniae

    Smirnov, Ilja

    2007-01-01

    Narva linna Kaubandus-Tööstuskoda alustas ѕauhindadeؤ väljaandmist kõige parema ja kõige halvema teo sooritanud Narva ärimehele. ѕParima teo tegijale antakse skulptor Aivar Simsoni poolt valmistatud pronkskuju ѕLendav Kalevipoegؤ ja halvima teo tegijale jääb ѕSittuv koerؤ

  14. Suurtelt telekomidelt kutsuv toon / Margo Kokerov

    Index Scriptorium Estoniae

    Kokerov, Margo, 1978-

    2007-01-01

    Ülevaade AS Eesti Telekom, AB TEO LT ja AS Starman tegevusest ja majandusnäitajatest eesmärgiga välja selgitada, millisesse neist on otstarbekas investeerida. Tabel: Hinnasihid ja soovitused; Starman: kümne kuuga +30%. Vt. samas: Eesti Telekom (ETLAT); TEO (TEO1L); Starman (SMN)

  15. Characterization of p-Type CdTe Electrodes in Acetonitrile/Electrolyte Solutions. Nearly Ideal Behavior from Reductive Surface Pretreatments.

    Science.gov (United States)

    1983-06-30

    using Ag conductive palnt and the entire assembly was mounted in glass tubing with ordinary epoxy leaving only the front crystal face, ...energy set, several eV higher than either Te2- or Teo (as measured for sputtered CdTe and Te, respectively) is assigned to TeO2 , the lowest stable...binding energy reported for TeO2 (575.9 eV). 33 The lower binding energy set of bands, lying midway between Teo and Te2 - , results from both Teo and

  16. Structure of zinc and niobium tellurite glasses by neutron and x-ray diffraction

    International Nuclear Information System (INIS)

    Hoppe, U; Yousef, E; Ruessel, C; Neuefeind, J; Hannon, A C

    2004-01-01

    Neutron and x-ray diffraction experiments of high resolving power with neutrons from a spallation source and high-energy photons from a synchrotron have been performed on compositional series of binary Zn, Nb and on mixed Zn/Nb tellurite glasses. The Te-O, Zn-O and Nb-O coordination numbers are determined by Gaussian fitting of the first-neighbour peaks in the neutron and x-ray data simultaneously. The transition of TeO 4 to TeO 3 units with increasing fraction of a second component is indicated by decreasing total Te-O coordination numbers. This transition appears different for glasses with ZnO or Nb 2 O 5 additions. Details of the Te-O peaks suggest there are two species of Te-O bonds with lengths of ∼ 0.19 and ∼ 0.21 nm. The change of their fractions shows excellent agreement with the existence of TeO 4 trigonal bipyramids and TeO 3 trigonal pyramids. All oxygen atoms from ZnO and Nb 2 O 5 are used for rupture of Te-O-Te bridges, which is accompanied with a change of nearly all participating TeO 4 to TeO 3 groups. The tendency for a TeO 4 → TeO 3 change decreases for glasses of higher second component content which is accompanied by the occurrence of TeO 4 groups with non-bridging oxygens. The Nb tellurite glasses show transition to network-forming behaviour with the formation of Nb-O-Nb bridges. The fractions of TeO 3 units of ternary Zn/Nb tellurite glasses agree with an additivity behaviour of the modifying effects of ZnO and Nb 2 O 5 additions

  17. Raman spectrum, quantum mechanical calculations and vibrational assignments of (95% alpha-TeO2/5% Sm2O3) glass.

    Science.gov (United States)

    Shaltout, I; Mohamed, Tarek A

    2007-06-01

    Chozen system of tellurite glasses doped with rare earth oxides (95% alpha-TeO(2)+5% Sm2O3) was prepared by melt quenching. Consequently, the Raman spectrum (150-1250 cm(-1)) of the modified tellurite have been recorded. As a continuation to our normal coordinate analysis, force constants and quantum mechanical (QM) calculations for tbp TeO4(4-) (triagonal bipyramid, C(2v)) and TeO(3+1); Te2O7(6-) (bridged tetrahedral), we have carried out ab initio frequency calculations for tpy TeO3(2-) (triagonal pyramidal, C(3v) and C(s)) and tp TeO3(2-) (triagonal planar, D(3h)) ions. The quantum mechanical calculations at the levels of RHF, B3LYP and MP2 allow confident vibrational assignments and structural identification in the binary oxide glass (95% alpha-TeO2 +5% Sm2O3). The dominant three-dimensional network structures in the modified glass are triagonal pyramidal TeO3 with minor features of short range distorted tbp TeO4 and bridged tetrahedral unit of TeO(3+1), leading to a structure of infinite chain. Therefore, alpha-TeO2/Sm2O3 (95/5%) glass experience structural changes from TeO4 (tbp); Te2O7 (TeO(3+1))-->TeO3 (tpy).

  18. Raske tervisekahjustuse tekitamise katse. Riigikohtu kriminaalkolleegiumi otsus asjas 3-1-1-111-16 / Mario Truu

    Index Scriptorium Estoniae

    Truu, Mario, 1989-

    2017-01-01

    Riigikohtu kriminaalkolleegiumi otsusest asjas 3-1-1-111-16, teo toimepanija tahtlusest raske tervisekahjustuse tekitamise katse korral. Tervisekahjustuse liigi ja raskuse tuvastamisest kriminaalkohtumenetluses

  19. Evolution of local structure in Ag2O-TeO2 glasses with addition of Ag2O analyzed by pulsed neutron diffraction and Raman spectroscopy

    International Nuclear Information System (INIS)

    Iwadate, Yasuhiko; Suzuki, Mineta; Hattori, Takeo; Fukushima, Kazuko; Nishiyama, Shin; Misawa, Masakatsu; Fukunaga, Toshiharu; Itoh, Keiji

    2005-01-01

    The local structure of Ag 2 O-TeO 2 glasses was studied by time-of-flight pulsed neutron diffraction (TOF-PND) and Raman spectroscopy. The results of Raman spectroscopy indicated that TeO 4 trigonal bipyramidal units (tbp) were converted to TeO 3 trigonal pyramidal units (tp) by addition of Ag 2 O to TeO 2 . Furthermore in PND, the structural parameters for each atomic pair were optimized in the Q-space, and the distances of the near neighbor Te-O correlations forming tbp units and tp units in the network were estimated with some accuracy

  20. Hybrid Coatings Enriched with Tetraethoxysilane for Corrosion Mitigation of Hot-Dip Galvanized Steel in Chloride Contaminated Simulated Concrete Pore Solutions

    Science.gov (United States)

    Figueira, Rita B.; Callone, Emanuela; Silva, Carlos J. R.; Pereira, Elsa V.; Dirè, Sandra

    2017-01-01

    Hybrid sol-gel coatings, named U(X):TEOS, based on ureasilicate matrices (U(X)) enriched with tetraethoxysilane (TEOS), were synthesized. The influence of TEOS addition was studied on both the structure of the hybrid sol-gel films as well as on the electrochemical properties. The effect of TEOS on the structure of the hybrid sol-gel films was investigated by solid state Nuclear Magnetic Resonance. The dielectric properties of the different materials were investigated by electrochemical impedance spectroscopy. The corrosion behavior of the hybrid coatings on HDGS was studied in chloride-contaminated simulated concrete pore solutions (SCPS) by polarization resistance measurements. The roughness of the HDGS coated with hybrids was also characterized by atomic force microscopy. The structural characterization of the hybrid materials proved the effective reaction between Jeffamine® and 3-isocyanate propyltriethoxysilane (ICPTES) and indicated that the addition of TEOS does not seem to affect the organic structure or to increase the degree of condensation of the hybrid materials. Despite the apparent lack of influence on the hybrids architecture, the polarization resistance measurements confirmed that TEOS addition improves the corrosion resistance of the hybrid coatings (U(X):TEOS) in chloride-contaminated SCPS when compared to samples prepared without any TEOS (U(X)). This behavior could be related to the decrease in roughness of the hybrid coatings (due TEOS addition) and to the different metal coating interaction resulting from the increase of the inorganic component in the hybrid matrix. PMID:28772667

  1. Annual Technical Report, Materials Research Laboratory, July 1, 1980-June 30, 1981,

    Science.gov (United States)

    1981-06-30

    as a function of glass composi- tion. The appearance of non-zero values for N4 in the TeO2 -B2 0 3-A 20 3 glasses and the enhancement of N 4 in the...Li2 0-TeO 2-B 20 3 glasses above that obtained for the binary Li2 O-B 20 3 glass system indicates that the TeO2 in the glasses contributes to the...describing Ve behavior of N4 for the binary TeO2 -B203 system have been inferred from the results secured for the ternary glasses . Principal

  2. 30. VI avati Pärnus Lõuna tänav 20 hoovis taas Rael Arteri galerii

    Index Scriptorium Estoniae

    2005-01-01

    Hooaeg avatakse graafilise disaineri Jaan Evarti väljapanekuga "Erinevad esitajad" ja sloveenia meediakunstniku Teo Spilleri kontseptsiooniaktsiooniga. Avamispidustuste helid ja rütmid: Aivar Tõnso

  3. Seed germination and seedling vigour of italian ryegrass, cocksfoot and timothy following harvest and storage Germinação de sementes e o vigor de plantas jovens de azevem italiano, dactilis e timóteo após a colheita e o armazenamento

    Directory of Open Access Journals (Sweden)

    Rade Stanisavljevic

    2011-12-01

    Full Text Available During post-harvest maturation, different species vary in the length of dormancy breaking or germination increases. Seed dormancy and slow seedling development often limit establishment of forage grass stands. Seed germination and seedling vigour of Italian ryegrass (Lolium italicum A. Braun, Synonym Lolium multiflorum L., cocksfoot (Dactylis glomerata L. and timothy (Phleum pretense L. were observed after harvest and storage. After harvest in June, seeds were stored under standard storage conditions and sampled every 30 days after harvest (DAH, up to 270 DAH, and then every 60 days up to 990 DAH. At each date, seeds were tested for final germination percentage and for seedling vigour traits. Timothy seeds had a maximum germination (88% and the best seedlings vigour at 90 DAH, which implies that early autumn (September-October is the best sowing period for freshly harvested seeds of timothy. Timothy seed germination was poor from 270 DAH (73%. The best germination and vigour of Italian ryegrass and cocksfoot seedlings were between 270 and 330 DAH, which equates to spring sowing time (March-April in the succeeding year. Cocksfoot and Italian ryegrass seeds maintained satisfactory germination levels up to 630 DAH (81% and 810 DAH (81%, respectively. The data can serve for the determination of a proper storage duration management between harvest and sowing of the tested species under ambient conditions of south-eastern Europe.Durante o armazenamento, diferentes espécies comportam-se diferentemente quanto à dormência e crescimento de plântulas. A dormência o desenvolvimento lento das plântulas limitam a época do plantio das gramíneas forrageiras plurianuais. A germinação de sementes e o crescimento das plântulas de azevem italiano (Lolium italicum A. Braun sin. Lolium multiflorum L., Dactilis (Dactilis glomerata L. e de timoteo (Phleum pratense L. foi pesquisada durante a maturação pós-colheita e a silagem. Após a colheita, em junho, sementes foram armazenadas em condições tradicionais e analisadas a cada 30 dias após a colheita, até 270 dias e, em seguida, a cada 60 dias até 990 dias. Nessa pesquisa, avaliou-se a germinação final e o vigor das plântulas. As sementes de timoteo obtiveram germinação máxima (88% e o melhor crescimento das plântulas após 90 dias de armazenamento, indicando que o melhor período para o plantio das sementes colhidas em junho é o inicio de outono (setembro-outubro. A germinação de sementes de timoteo reduziu nos 270 dias (73% seguintes. A melhor germinação, e crescimento da plântula do azevem italiano e do dactilis ocorreu entre 270 e 330 dias, indicando que a melhor época para plantio é na primavera (março-abril, do ano seguinte. As sementes de dactilis e azevem italiano mantiveram germinação satisfatória até 630 dias (81% e 810 dias (81%, respectivamente. Essa pesquisa pode servir para determinação de gerenciamento adequado de duração de armazenamento entre a colheita e o plantio das espécies testadas em condições de armazenamento no sudeste da Europa.

  4. Milline/millised viimastel aastatel eesti keeles ilmunud ilukirjandusteos(ed) on pälvinud liiga vähe tähelepanu või jäänud ebaõiglaselt tähelepanuta? Miks võiks antud teos(t)ele rohkem tähelepanu juhtida? : [küsitlus] / Doris Kareva, Berk

    Index Scriptorium Estoniae

    2010-01-01

    Nimetatakse konkreetseid teoseid, näiteks Berk Vaher kirjutab Andi Meistri romaanist "Valgus olematust aknast" (2009), Mihkel Mutt Marcin Świetlicki kriminaalromaanist "Kaksteist" (tlk. Hendrik Lindepuu, 2009), Aare Pilv, Eliina Kortsu luulekogust "Lööklaused murravad metsi" (2006), Jaak Tomberg Vahur Afanasjevi luulekogust "Katedraal Emajões" (2006), Birk Rohelend Siim Nurkliku näidendist "Kas ma olen nüüd elus" (2010), Igor Kotjuh Toomas Raudami proosapalast "Mees, kes kirjutas merd" (2006). Enim muretsetakse tõlkekirjanduse, eriti luule retseptsiooni puudumise pärast

  5. Acute and subchronic toxicity as well as mutagenic evaluation of essential oil from turmeric (Curcuma longa L).

    Science.gov (United States)

    Liju, Vijayasteltar B; Jeena, Kottarapat; Kuttan, Ramadasan

    2013-03-01

    The present study investigated the acute, subchronic and genotoxicity of turmeric essential oil (TEO) from Curcuma longa L. Acute administration of TEO was done as single dose up to 5 g of TEO per kg body weight and subchronic toxicity study for thirteen weeks was done by daily oral administration of TEO at doses 0.1, 0.25 and 0.5 g/kg b.wt. in Wistar rats. There were no mortality, adverse clinical signs or changes in body weight; water and food consumption during acute as well as subchronic toxicity studies. Indicators of hepatic function such as aspartate aminotransferase (AST), alanine amino transferase (ALT) and alkaline phosphatase (ALP) were unchanged in treated animals compared to untreated animals. Oral administration of TEO for 13 weeks did not alter total cholesterol, triglycerides, markers of renal function, serum electrolyte parameters and histopathology of tissues. TEO did not produce any mutagenicity to Salmonella typhimurium TA-98, TA-100, TA-102 and TA-1535 with or without metabolic activation. Administration of TEO to rats (1 g/kg b.wt.) for 14 days did not produce any chromosome aberration or micronuclei in rat bone marrow cells and did not produce any DNA damage as seen by comet assay confirming the non toxicity of TEO. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Polysiloxanes derived from the controlled hydrolysis of tetraethoxysilane as precursors to silica for use in ceramic processing

    Science.gov (United States)

    Philipp, Warren H.

    1990-01-01

    Synthesis, properties, and potential applications in ceramic processing for two polysiloxane silica precursors derived from the controlled hydrolysis of tetraethoxysilane (TEOS) are presented. The higher molecular weight TEOS-A is a thick adhesive liquid of viscosity 8000 to 12,000 c.p. having a SiO2 char yield of about 55 percent. The lower molecular weight TEOS-B is a more fluid liquid of viscosity 150 to 200 c.p. having a SiO2 char yield of about 52 percent. The acid catalyzed hydrolysis of TEOS to hydrated silica gel goes through a series of polysiloxane intermediates. The rate of this transition increases with the quantity of water added to the TEOS; thus, for ease of polymer isolation, the amount of water added must be carefully determined so as to produce the desired polymer in a reasonable time. The water to TEOS mole ratio falls in the narrow range of 1.05 for TEOS-A and 0.99 for TEOS-B. Further polymerization or gelation is prevented by storing at -5 C in a freezer. Both polysiloxanes thermoset to a glassy solid at 115 C. The liquid polymers are organic in nature in that they are miscible with toluene and ethanol, slightly souble in heptane, but immiscible with water. For both polymers, results on viscosity versus time are given at several temperatures and water additions. Based on these results, some examples of practical utilization of the precursors for ceramic fabrication are given.

  7. Dehydration of an ethanol/water azeotrope by novel organic-inorganic hybrid membranes based on quaternized chitosan and tetraethoxysilane.

    Science.gov (United States)

    Uragami, Tadashi; Katayama, Takuya; Miyata, Takashi; Tamura, Hiroshi; Shiraiwa, Tadashi; Higuchi, Akon

    2004-01-01

    To control swelling of quaternized chitosan (q-Chito) membranes, mixtures of q-Chito as an organic component and tetraethoxysilane (TEOS) as an inorganic component were prepared using the sol-gel reaction, and novel q-Chito/TEOS hybrid membranes were formed. In the separation of an ethanol/water azeotrope by pervaporation, the effect of TEOS content on the water/ethanol selectivity of q-Chito/TEOS hybrid membranes was investigated. Hybrid membranes containing up to 45 mol % TEOS exhibited higher water/ethanol selectivity than the q-Chito membrane. This resulted from depressed swelling of the membranes by formation of a cross-linked structure. However, introduction of excess TEOS led to greater swelling of the hybrid membranes. Therefore, the water/ethanol selectivity of the hybrid membranes containing more than 45 mol % TEOS was lower than that of the q-Chito membrane. The relationship between the structure of q-Chito/TEOS hybrid membranes and their permeation and separation characteristics during pervaporation of an ethanol/water azeotrope is discussed in detail.

  8. Mida lugeja raamatukogult tegelikult ootab / Ene Riet

    Index Scriptorium Estoniae

    Riet, Ene, 1954-

    2011-01-01

    4. teadus- ja erialaraamatukogude päev toimus 21. oktoobril 2011 Eesti Muusika- ja Teatriakadeemias. Teadusraamatukogu aasta teo auhinna pälvis Urmas Sinisalu tulemusliku ja innovaatilise töö eest raamatukogude infosüsteemi ESTER arendamisel. Erialaraamatukogu aasta teo auhinna sai TÜ ajakirjanduse ja kommunikatsiooni instituudi raamatukoguhoidja Maio Vaniko raamatukogundust arendava tegevuse eest

  9. Growth of amorphous TeOx (2≤x≤3) thin film by radio frequency sputtering

    International Nuclear Information System (INIS)

    Dewan, Namrata; Gupta, Vinay; Sreenivas, K.; Katiyar, R. S.

    2007-01-01

    Thin films of Tellurium oxide TeO x over a wide range of x (2 to 3) were prepared by radio frequency diode sputtering at room temperature on corning glass and quartz substrate. The deposited films are amorphous in nature and IR spectroscopy reveals the formation of Te-O bond. X-ray photoelectron spectroscopy shows the variation in the stoichiometry of TeO x film from x=2 to 3 with an increase in oxygen percentage (25 to 100%) in processing sputtering gas composition. Raman spectroscopy depicts the formation of TeO 3 trigonal pyramid besides TeO 4 disphenoid in the amorphous TeO x film with increase in the value of x. The varying stoichiometry of TeO x thin film (x=2 to 3) was found to influence the optical, electrical, and elastic properties. The optical band gap of film increases from 3.8 to 4.2 eV with increasing x and is attributed to the decrease in density. The elastic constants (C 11 and C 44 ) of the deposited films are lower than the corresponding value reported for TeO 2 single crystal

  10. Structure and properties of hybrid poly(2-hydroxyethyl methacrylate)/SiO2 monoliths

    DEFF Research Database (Denmark)

    Ji, Xiangling; Jiang, Shichun; Qiu, Xuepeng

    2003-01-01

    Abstract: Hybrid poly(2-hydroxyethyl methacrylate) (PHEMA)/SiO2 monoliths were synthesized via a sol-gel process of the precursor tetraethyl orthosilicate (TEOS) and the in situ free-radical polymerization of 2-hydroxyethyl methacrylate (HEMA). The weight ratio of the starting chemicals, TEOS...

  11. Structural characterization of ZnCl2 modified tellurite based glasses

    Science.gov (United States)

    Dhankhar, Sunil; Kundu, R. S.; Punia, R.; Sunita, Parmar, R.; Sanjay, Kishore, N.

    2016-05-01

    Glass composition 70 TeO2-(30-x) BaO - x ZnCl2; x = 5, 10, 15, 20 and 25 have been prepared by rapid melt quenching technique under controlled atmospheric conditions. Amorphous nature of the samples was confirmed by x-ray diffractogram. The glass transition temperature (Tg) has been determined using differential scanning calorimetry (DSC) and its value is observed to decrease with increase in ZnCl2 content. The peaks in the Raman and FTIR spectra have been estimated by deconvolutation of the spectra and each of deconvoluted spectra exhibits several peaks. IR and Raman spectra of the present glass system indicate that TeO2 exists as TeO3 trigonal pyramidal (tp), TeO4 trigonal bipyramidal (tbp) and TeO6 polyhedra structural units. With increase in zinc halide content, transformation of some of TeO4 structural units into TeO3 structural units is observed Increase in TeO3 structural units shows that non-bridging oxygen contribution increases which confirms the decrease in glass transition temperature.

  12. Materials Approach to Dissecting Surface Responses in the Attachment Stages of Biofouling Organisms

    Science.gov (United States)

    2016-04-25

    dimethylaminopropyl- triethoxysilane (DMAP), and trimethylammoniumpropyltriethoxysilane ( TMAP ) were prepared to give xerogel formulations in the following...90 TMAP /TEOS, and 10:90 COE/TEOS. These surfaces were used as standards in all biological assays 4) Five fouling organisms (barnacles, Balanus

  13. Füüsilisele isikule mõistetavate põhi- ja lisakaristuste liigid ja määrad karistusseadustikus : [bakalaureusetöö] / Liine Reinmaa ; Tartu Ülikool, õigusteaduskond ; juhendaja: Mervi Kruusamäe

    Index Scriptorium Estoniae

    Reinmaa, Liine

    2010-01-01

    Karistuse mõistest ja selle tunnustest, karistusliikidest ja -määradest. Füüsilisele isikule kuriteo, väärteo või süüteo eest kohaldatavatest põhikaristustest, süüteo eest kohaldatavatest lisakaristustest

  14. Development of Molybdenum Adsorbent for 99Mo/99mTc Radioisotope Generator Based on Irradiated Natural Molybdenum

    International Nuclear Information System (INIS)

    Rohadi Awaludin; Hotman Lubis; Sriyono; Abidin; Herlina; Endang Sarmini; Indra Saptiama; Hambali

    2011-01-01

    Preparation of 99 Mo/ 99m Tc radioisotope generator using irradiated natural molybdenum requires an adsorbent with high absorption capacity. Zirconium-based materials (ZBM), adsorbent with adsorption capacity of about 183 mg(Mo) / g(adsorbent), has been successfully synthesized. However, the adsorbent was easily broken in the Mo adsorption process due to many fractures in the grain. To increase the hardness, the material was immersed in tetraethyl orthosilicate (TEOS) and coated by TEOS flow in a column. The hardness test results showed that the ZBM with TEOS treatment was not broken when immersed into the Mo solution. Observations using SEM showed that the fractures formed on the ZBM were successfully removed by TEOS treatment. Measurements using EDS showed that after TEOS treatment, the silicon was detected and the oxygen content increased in the material surface. Adsorption test results showed that the TEOS immersion decreased the adsorption capacity of molybdenum from 183 to 79.8 mg of Mo per gram of adsorbent. The TEOS flow-in a column gave material with relatively high adsorption capacity, 140 mgMo per gram adsorbent. The content of Silicon in the surface was lower than that of adsorbent immersed in TEOS. (author)

  15. Bulletin of Materials Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    The addition of alkali modifier in the tellurite network leads to the conversion of the TeO4 units to TeO3 units with a varying number of non-bridging oxygen atoms. Emphasis has also been given to the lowfrequency modes and particular points related to the low-frequency Raman phenomenology are discussed in view of the ...

  16. Pärnu aasta tegu on spordihall / Iira Igasta

    Index Scriptorium Estoniae

    Igasta, Iira, 1952-

    2009-01-01

    Pärnu linnavalitsuse ja Pärnu Postimehe korraldatud aasta teo konkursi võitis 2009. aastal Pärnu spordihall. Võitjale antakse üle keraamik Ene Tapferi valmistatud kuju, kirjakunstnik Vello Paluoja kujundatud auaadress ja Pärnu Postimehe esimese numbri faksiimiletrükk. Loetletud Aasta teo tunnustuse pälvinud alates aastast 2001

  17. Structure of zinc and niobium tellurite glasses by neutron and x-ray diffraction

    Science.gov (United States)

    Hoppe, U.; Yousef, E.; Rüssel, C.; Neuefeind, J.; Hannon, A. C.

    2004-03-01

    Neutron and x-ray diffraction experiments of high resolving power with neutrons from a spallation source and high-energy photons from a synchrotron have been performed on compositional series of binary Zn, Nb and on mixed Zn/Nb tellurite glasses. The Te-O, Zn-O and Nb-O coordination numbers are determined by Gaussian fitting of the first-neighbour peaks in the neutron and x-ray data simultaneously. The transition of TeO4 to TeO3 units with increasing fraction of a second component is indicated by decreasing total Te-O coordination numbers. This transition appears different for glasses with ZnO or Nb2O5 additions. Details of the Te-O peaks suggest there are two species of Te-O bonds with lengths of {\\sim }0.19 and {\\sim }0.21 nm. The change of their fractions shows excellent agreement with the existence of TeO4 trigonal bipyramids and TeO3 trigonal pyramids. All oxygen atoms from ZnO and Nb2O5 are used for rupture of Te-O-Te bridges, which is accompanied with a change of nearly all participating TeO4 to TeO3 groups. The tendency for a {\\mathrm {TeO}}_{4} \\to {\\mathrm {TeO}}_{3} change decreases for glasses of higher second component content which is accompanied by the occurrence of TeO4 groups with non-bridging oxygens. The Nb tellurite glasses show transition to network-forming behaviour with the formation of Nb-O-Nb bridges. The fractions of TeO3 units of ternary Zn/Nb tellurite glasses agree with an additivity behaviour of the modifying effects of ZnO and Nb2O5 additions. Some of these results have already been presented in thesis work: Yousef E 2003 A study of some physical properties of tellurite glass (Al-Azhar University, Assiut Egypt).

  18. Mass spectrometric study of vaporization of cesium tellurate and tellurite

    International Nuclear Information System (INIS)

    Semenov, G.A.; Fokina, L.A.; Mouldagalieva, R.A.

    1994-01-01

    The process of vaporization of cesium tellurate and tellurite was studied by the Knudsen effusion method with a mass spectrometric analysis of the vapor composition. The thermal dissociation of Cs 2 TeO 4 to Cs 2 TeO 3 and the congruent vaporization of Cs 2 TeO 3 were established. Thermodynamic functions for gaseous Cs 2 TeO 3 have been calculated. The standard enthalpy of sublimation Δ s H (298.15)=268.1±13.0 kJ mol -1 was determined by the 2nd and 3rd laws of thermodynamics. The enthalpy of formation Δ f H (298.15)=-725.1±13.0 kJ mol -1 for gaseous Cs 2 TeO 3 and the enthalpy of atomization Δ at H (298.15)=1841.3±15.0 kJ mol -1 have been computed. ((orig.))

  19. Anti-arthritic effects and toxicity of the essential oils of turmeric (Curcuma longa L.).

    Science.gov (United States)

    Funk, Janet L; Frye, Jennifer B; Oyarzo, Janice N; Zhang, Huaping; Timmermann, Barbara N

    2010-01-27

    Turmeric (Curcuma longa L., Zingiberaceae) rhizomes contain two classes of secondary metabolites, curcuminoids and the less well-studied essential oils. Having previously identified potent anti-arthritic effects of the curcuminoids in turmeric extracts in an animal model of rheumatoid arthritis (RA), studies were undertaken to determine whether the turmeric essential oils (TEO) were also joint protective using the same experimental model. Crude or refined TEO extracts dramatically inhibited joint swelling (90-100% inhibition) in female rats with streptococcal cell wall (SCW)-induced arthritis when extracts were administered via intraperitoneal injection to maximize uniform delivery. However, this anti-arthritic effect was accompanied by significant morbidity and mortality. Oral administration of a 20-fold higher dose TEO was nontoxic, but only mildly joint-protective (20% inhibition). These results do not support the isolated use of TEO for arthritis treatment but, instead, identify potential safety concerns in vertebrates exposed to TEO.

  20. Short-range structure and thermal properties of lead tellurite glasses

    Science.gov (United States)

    Hirdesh, Kaur, Amarjot; Khanna, Atul; Gonzàlez, Fernando

    2017-05-01

    PbO-TeO2 glasses having composition: xPbO-(100 - x)TeO2 (x = 10, 15 and 20 mol%) were prepared by melt quenching and characterized by X-ray diffraction, density measurements, differential scanning calorimetry and Raman spectroscopy. Glass density increases from 5.89 to 6.22 g cm-3 with increase in PbO concentration from 10 to 20 mol%, due to the replacement of TeO2 by heavier PbO. DSC studies found that glass transition temperature (Tg) decreases from a value of 295°C to 281°C. Raman studies found that glass short-range structure consists of TeO4 and TeO3 structural units and that PbO modifies the network by the structural transformation: TeO4 to TeO3.

  1. Acousto-Optic Beam Steering Study

    Science.gov (United States)

    1994-08-01

    S25 2.500000 PRIVATE CATALOG PWL 830.00 ’THIN’ 1.010000 PWL 830.00 ’ TEO2 ’ 2.200000 REFRACTIVE INDICES GLASS CODE 830.00 SF57 SCHOTT 1.821707 SF11...10.000000 PRIVATE CATALOG PWL 830.00 ’ TEO2 ’ 2.200000 REFRACT IVE :NDICES GLASS CODE 830.00 BK7 SCHCTT 1.510206 ’ TEO2 ’ 2.200000 39 Table 4.2.2-3. Mid...4.1-2 Acoustic Material Figure-of-Merit Trade 11 4.1-3 Degenerate Response in On-Axis TeO 2 12 4. 1-4 Rotated AO Interaction in TeO2 : High-Band Mode 13

  2. Short-range structure and thermal properties of barium tellurite glasses

    Science.gov (United States)

    Kaur, Amarjot; Khanna, Atul; Gonzàlez, Fernando

    2017-05-01

    BaO-TeO2 glasses containing 10 to 20 BaO mol% were prepared and characterized by X-ray diffraction, density measurements, differential scanning calorimetry and Raman spectroscopy. Glass density decreases with increase in BaO concentration from 10 to 20 mol%, due to replacement of heavier TeO2 by lighter BaO, however glass transition temperature (Tg) increases significantly from a value of 318°C to 327°C due to increase in average single bond enthalpy of the tellurite network. Raman studies found that glass short-range structure consists of TeO4 and TeO3 structural units and BaO modifies the network by producing the structural transformation: TeO4→ TeO3.

  3. New Functionalized Sol-Gel Hybrid Sorbent Coating for Stir Bar Sorptive Extraction of Selected Non-Steroidal Anti Inflammatory Drugs in Human Urine Samples

    International Nuclear Information System (INIS)

    Mashkurah Abd Rahim; Wan Aini Wan Ibrahim; Zainab Ramli; Mohd Marsin Sanagi

    2015-01-01

    A new sol-gel hybrid material, methyltrimethoxysilane-cyanopropyltriethoxysilane (MTMOS-CNPrTEOS) was successfully synthesized and used as a coating material in stir bar sorptive extraction (SBSE) of selected non-steroidal anti-inflammatory drugs (NSAIDs) in urine samples. The MTMOS-CNPrTEOS hybrid was synthesized by hydrolysis and condensation of MTMOS and CNPrTEOS in the presence of trifluoroacetic acid as catalyst via sol-gel method. Several factors influencing the synthesized sol-gel hybrid MTMOS-CNPrTEOS process such as mole ratio of MTMOS-CNPrTEOS, NaOH concentrations as etching solution, etching time, coating time and water content were investigated and optimized in this study. The optimum synthesis conditions obtained were 1:1 mol ratio of MTMOS-CNPrTEOS, 1 M NaOH as etching solution, 60 min etching time, 2 h coating time and 6 mmol water. The sol-gel hybrid MTMOS-CNPrTEOS synthesized under the optimum conditions was used to determine selected NSAIDs in human urine samples using normal stacking mode capillary electrophoresis with ultraviolet detection. MTMOS-CNPrTEOS SBSE method demonstrated good linearity (60 to 20,000 μg L -1 ) with excellent coefficient of determination (r 2 > 0.9990). The sol-gel hybrid MTMOS-CNPrTEOS SBSE method showed low limit of detection (35 - 41 μg L -1 ) with good precision (RSD < 6 %, n = 3) and excellent extraction recoveries (83.5 - 98.9 %) for the selected NSAIDs. The sol-gel hybrid MTMOS-CNPrTEOS SBSE method demonstrated good potential as an alternative sorbent in SBSE method for NSAIDs. (author)

  4. Structure and thermal properties of nanospheres obtained by ethoxy silanes copolymerization

    International Nuclear Information System (INIS)

    Pedroso, Marcos A.S.; Mothe, Cheila G.; Dias, Marcos L.

    2001-01-01

    Thermal and structural characterization of organophylic nano spherical copolymers of tetra ethoxysilane (TEOS) and methyltriethoxysilane (MTEOS) or dimethyldiethoxysilane (DMDEOS) obtained by sol-gel reaction terminated by trimethylchlorosilane are described. 29 Si NMR, wide angle X-ray scattering (WAXS) and thermal analysis (TG/DTG and DTA) were employed. Due to the high reactivity of TEOS, the copolymers are silica-silicon hybrids showing bilayer structure where silica constitutes a core and a alkyl-rich chemical structure constitutes the external layer. The copolymers present higher mass lost at high temperatures than TEOS homopolymer. (author)

  5. The Milano-Gran Sasso double beta decay experiment: toward a 20-crystal array

    International Nuclear Information System (INIS)

    Alessandrello, A.; Brofferio, C.; Bucci, C.; Cremonesi, O.; Fiorini, E.; Giuliani, A.; Nucciotti, A.; Pavan, M.; Pessina, G.; Previtali, E.; Zanotti, L.

    1996-01-01

    TeO 2 thermal detectors are being used by the Milano group to search for neutrinoless double beta decay of 130 Te. An upper limit for neutrinoless decay half life of 2.1 x 10 22 yr at 90% CL obtained with a 334 g TeO 2 detector has been previously reported. To improve the sensitivity of the experiment an array of twenty 340 g TeO 2 crystals will be realised in the next future. As a first step toward the realisation of that experiment a 4 crystal detector has been tested in the Gran Sasso refrigerator. Detector performances, data acquisition and analysis are discussed. (orig.)

  6. Hydrophobicity of silica thin films: The deconvolution and interpretation by Fourier-transform infrared spectroscopy

    Science.gov (United States)

    Saputra, Riza Eka; Astuti, Yayuk; Darmawan, Adi

    2018-06-01

    This work investigated the synthesis of dimethoxydimethylsilane:tetraethoxysilane (DMDMS:TEOS) silica thin films as well as the effect of DMDMS:TEOS molar ratios and calcination temperature on hydrophobic properties of silica thin films and its correlation with the FTIR spectra behaviour. The silica thin films were synthesized by sol-gel method using combination of DMDMS and TEOS as silica precursors, ethanol as solvent and ammonia as catalyst, with DMDMS and TEOS molar ratio of 10:90, 25:75, 50:50, 75:25 and 90:10. The results showed that DMDMS:TEOS molar ratio had significant impact on the hydrophobic properties of silica thin films coated on a glass surface. Furthermore, the correlation between water contact angle (WCA) and DMDMS:TEOS molar ratio was found to be in a parabolic shape. Concurrently, the maximum apex of the parabola obtained was observed on the DMDMS:TEOS molar ratio of 50:50 for all calcination temperature. It was clearly observed that the silica xerogel exhibiting notable change in relative peak intensities showed FTIR peak splitting of υasymmetric Si-O-Si. To uncover what happened at the FTIR peak, the deconvolution was conducted in Gaussian approach. It was established that the changes in the Gaussian peak component were related to DMDMS:TEOS molar ratios and the calcination temperature that allowed us to tailor the DMDMS:TEOS silica polymer structure model based on the peak intensity ratios. With the increase of DMDMS:TEOS molar ratio, the ratio of (cyclic Si-O-Si)/(linear Si-O-Si) decreased, whilst the ratio of (C-H)/(linear Si-O-Si) increased. Both ratios intersected at DMDMS:TEOS molar ratio of 50:50 with contribution factor ratio of 1:16 and 1:50 for silica xerogel calcined at 300 °C and 500 °C respectively. The importance of this research is the DMDMS:TEOS molar ratio plays an important role in determining the hydrophobic properties of thin films.

  7. Hydrophobicity of silica thin films: The deconvolution and interpretation by Fourier-transform infrared spectroscopy.

    Science.gov (United States)

    Saputra, Riza Eka; Astuti, Yayuk; Darmawan, Adi

    2018-03-14

    This work investigated the synthesis of dimethoxydimethylsilane:tetraethoxysilane (DMDMS:TEOS) silica thin films as well as the effect of DMDMS:TEOS molar ratios and calcination temperature on hydrophobic properties of silica thin films and its correlation with the FTIR spectra behaviour. The silica thin films were synthesized by sol-gel method using combination of DMDMS and TEOS as silica precursors, ethanol as solvent and ammonia as catalyst, with DMDMS and TEOS molar ratio of 10:90, 25:75, 50:50, 75:25 and 90:10. The results showed that DMDMS:TEOS molar ratio had significant impact on the hydrophobic properties of silica thin films coated on a glass surface. Furthermore, the correlation between water contact angle (WCA) and DMDMS:TEOS molar ratio was found to be in a parabolic shape. Concurrently, the maximum apex of the parabola obtained was observed on the DMDMS:TEOS molar ratio of 50:50 for all calcination temperature. It was clearly observed that the silica xerogel exhibiting notable change in relative peak intensities showed FTIR peak splitting of υ asymmetric Si-O-Si. To uncover what happened at the FTIR peak, the deconvolution was conducted in Gaussian approach. It was established that the changes in the Gaussian peak component were related to DMDMS:TEOS molar ratios and the calcination temperature that allowed us to tailor the DMDMS:TEOS silica polymer structure model based on the peak intensity ratios. With the increase of DMDMS:TEOS molar ratio, the ratio of (cyclic Si-O-Si)/(linear Si-O-Si) decreased, whilst the ratio of (C-H)/(linear Si-O-Si) increased. Both ratios intersected at DMDMS:TEOS molar ratio of 50:50 with contribution factor ratio of 1:16 and 1:50 for silica xerogel calcined at 300°C and 500°C respectively. The importance of this research is the DMDMS:TEOS molar ratio plays an important role in determining the hydrophobic properties of thin films. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Electrochromic Glasses.

    Science.gov (United States)

    1980-07-31

    this glass and that dipole-dipole correlations contribute to the "ferroelectric-like" character of this amorphous system. The TeO2 -W03 glasses can only...shows the dielectric constant and Fig. I(b) glass from pure TeO2 ot pure WO. In addition, glass the tan 8 of the WO glass as a function of temperature... glasses containing WO, in various glass forming nitworks of LifO-B1O0, Na:O-BzO,, and TeO2 were prepared from reagent grade oxides at 800 C - 9SO C in

  9. Raman band intensities of tellurite glasses.

    Science.gov (United States)

    Plotnichenko, V G; Sokolov, V O; Koltashev, V V; Dianov, E M; Grishin, I A; Churbanov, M F

    2005-05-15

    Raman spectra of TeO2-based glasses doped with WO3, ZnO, GeO2, TiO2, MoO3, and Sb2O3 are measured. The intensity of bands in the Raman spectra of MoO3-TeO2 and MoO3-WO3-TeO2 glasses is shown to be 80-95 times higher than that for silica glass. It is shown that these glasses can be considered as one of the most promising materials for Raman fiber amplifiers.

  10. Novel Optical Processor for Phased Array Antenna.

    Science.gov (United States)

    1992-10-20

    parallel glass slide into the signal beam optical loop. The parallel glass acts like a variable phase shifter to the signal beam simulating phase drift...A list of possible designs are given as follows , _ _ Velocity fa (100dB/cm) Lumit Wavelength I M2I1 TeO2 Longi 4.2 /m/ns about 3 GHz 1.4 4m 34 Fast...subject to achievable acoustic frequency, the preferred materials are the slow shear wave in TeO2 , the fast shear wave in TeO2 or the shear waves in

  11. Välismaalt

    Index Scriptorium Estoniae

    1999-01-01

    Leitud Beethoveni senitundmatu teos; Placido Domingo kui mehhiko rahvamuusika spetsialist; Barcelona ooper töötab jälle; Soome rahvusooper saab uue direktori; Sibeliuse muusika populaarsus kasvab Prantsusmaal

  12. Virksomhedens potentiale ligger i kundetilfredshed og -loyalitet

    DEFF Research Database (Denmark)

    Eskildsen, Jacob Kjær; Kristensen, Kai

    2008-01-01

    Denne artikel analyserer forholdet mellem kundetilfredshed, kundeloyalitet og forretningspotentialet set i forhold til nuværende kunder. Dataene stammer fra Dansk Kundetilfredshedsindeks 2006. Her vurderede i alt cirka 2000 privetkunder dres foretrukne skadesforsikringsselskab. Med baggrund i teo...

  13. Tehnilised stiilinäited / Margit Aedla

    Index Scriptorium Estoniae

    Aedla, Margit, 1970-

    2007-01-01

    Tutvustatakse LG Art Cool Air Conditioner'i, Electroluxi Global Design sarja sisseehitatavaid tooteid, Zanussi pliiti Teo ja pesumasinat Zoe ning 2007. a. iF disainiauhinna võitnud LG monitiri Fantasy ja LG mobiiltelefoni Chocolate (KG810)

  14. In Principio - rõõm Cantusest ja Pärdist, Tüürist rääkimata / Eeva Kumberg

    Index Scriptorium Estoniae

    Kumberg, Eeva, 1964-

    2009-01-01

    Nargen Festivali korraldatud kontserdist "In Principio" 3. juulil Tallinna Jaani kirikus, kus esinesid Eesti Filmarmoonia Kammerkoor, segakoorid Noorus ja Cantus, Nargen Festivali Orkester, esitati Erkki-Sven Tüüri teos "Requiem" ja Arvo Pärdi "In Principio"

  15. 101 sõbraga leedi / Jaan Mettik

    Index Scriptorium Estoniae

    Mettik, Jaan

    2007-01-01

    Virve Roosti toalilleraamatutest. Vt. samas: Kuidas sündis Virve Roosti viimane teos "Toalilleraamat. 101 rohelist sõpra?" ; Miks peab lillesõbra raamaturiiulis olema vähemalt üks Virve Roosti toalilleraamat?

  16. Bagatellid : maailm / Mailis Põld

    Index Scriptorium Estoniae

    Põld, Mailis

    2007-01-01

    Muusikasõnumeid mujalt maailmast: Tipptenor Roberto Alagna protsessib La Scalaga. Pariisis andis sooloõhtu Pierre-Laurent Aimard. Messiaeni viimase õpilase George Benjamini esimene ulatuslik teos ooperizhanris. Saadaval Glenn Gouldi klaveritoolid. Seminoli indiaanlased omandasid Hard Rock kohvikute keti

  17. Eesti kooriteose esiettekanne lätlastelt / Kersti Inno

    Index Scriptorium Estoniae

    Inno, Kersti, 1954-

    2003-01-01

    Ansambli LRC Chamber Singers kontsertidest Pärnu kontserdimaja kammersaalis 17. okt., Vanemuise kontserdimajas 18. okt., Rotermanni soolalaos 19. okt. Esiettekande tuleb NYYD 03 tellimusel valminud Rene Eespere ladinakeelne teos koorile ja vibrafonile "Armastaja sõnad"

  18. Ühest aia- ja pargikunstialasest raamatust Tallinna kaupmehe Martin Heinrich Gebaueri raamatukogus 18. sajandi II poolel ja sellega seonduvast / Risto Paju

    Index Scriptorium Estoniae

    Paju, Risto

    2012-01-01

    Tõenäoliselt oli varaloendis nimetatud teos Christian Cay Lorenz Hirschfeldi "Theorie der Gartenkunst". Tegemist oli oma ajastu moodsa teosega. Loodust ja aiandust käsitlevaid raamatuid oli Tallinna kaupmeeste ja literaatide biblioteekides teisigi. Martin Heinrich Gebaueri varaloendist

  19. Carlo Ginzburg: anomaalia viitab normile / intervjueerinud Marek Tamm

    Index Scriptorium Estoniae

    Ginzburg, Carlo, 1939-

    2014-01-01

    Intervjuu itaalia ajaloolase Carlo Ginzburgiga tema raamatu "Ükski saar pole saar : neli pilguheitu inglise kirjandusele globaalsest vaatenurgast" eesti keeles ilmumise puhul. Teos ilmus Tallinna Ülikooli Kirjastuses

  20. Maksualased süüteod : variisiku kasutamine Eestis : [bakalaureusetöö] / Nikolai Majerovitš ; Tartu Ülikool, õigusteaduskond ; juhendaja: Jaan Sootak

    Index Scriptorium Estoniae

    Majerovitš, Nikolai, 1986-

    2009-01-01

    Variisiku mõistest ja kasutamisest, maksualastest süüteokoosseisudest kriminaalkoodeksis ja karistusseadustikus, süüteo organisaatorist, süüteost osavõtust, juriidilise isiku kriminaal- ja väärteovastutusest

  1. Fine 5 tantsib Bachi järgi

    Index Scriptorium Estoniae

    2016-01-01

    Tantsuteater Fine 5 toob lavale lavastuse "HTK ehk hästi treenitud klaviir". Teos on loodud J.S. Bachi "Hästitempereeritud klaviiri" (HTK) esimese osa muusikale. Koreograafid Tiina Ollesk ja Renee Nõmmik

  2. Toivo Tulevile tunnustus Monacos

    Index Scriptorium Estoniae

    2005-01-01

    13. juunil Monacos toimunud prints Pierre'i fondi igaaastasest kompositsioonipreemiate jagamisest, kus T. Tulevi teos "Sans mesure" pälvis teise koha. Võitja oli prantsuse helilooja Frederic Durieux. Žüriisse kuulus ka Arvo Pärt

  3. Perceived usefulness and culture as predictors of teachers attitudes ...

    African Journals Online (AJOL)

    Sumaya Laher

    2015-11-24

    Nov 24, 2015 ... encourages creativity and promotes higher-order learning (Chai, Hong & Teo ... Teacher attitudes towards educational technology in. South Africa. Govender ..... As is evident from the demographic profile and scores on the ET ...

  4. Peegeldus ajas : aja, ruumi ja vormi kohtumispaik / Kaja Tooming

    Index Scriptorium Estoniae

    Tooming, Kaja

    2002-01-01

    Näited: Kimiyo Mishima skulptuur "Newspaper 84 - E" (1984) Hara Muuseumi aias Tokyos, Miyajima Tatsuo installatiivne teos "Keep Change, Connect with Everything, Continue Forever" (1998), Kyoto Kiyomizudera templi budistliku kalmistu hauakivid

  5. Vahur-Paul Põldma - tõlkis raamatu, lavastas etenduse, ise mängib ja üksi / Vahur-Paul Põldma ; interv. Triin Tael

    Index Scriptorium Estoniae

    Põldma, Vahur-Paul

    2008-01-01

    Alessandro Baricco teos "Novecento", mida Vahur-Paul Põldma mängib Uue Vana Teatri nime all ühemeheetendusena. Lisaks tutvustus "Kes on Alessandro Baricco?" ja "Vahur-Pauli salaminevik : töö lasteaiakasvatajana"

  6. Riigi rahvusvaheline vastutus erga omnes kohustuste rikkumisest Tðetðeenia relvakonflikti näitel : [bakalaureusetöö] / Martin Roger ; Tartu Ülikool, õigusteaduskond ; juhendaja: Kristi Land

    Index Scriptorium Estoniae

    Roger, Martin

    2001-01-01

    Riigi vastutuse üldisest iseloomust rahvusvahelises õiguses, teo omistatavus riigile, rahvusvahelise kohustuse rikkumine, Tshetsheenia konflikt kui siseriiklik relvastatud konflikt, Vene Föderatsiooni rahvusvahelise humanitaarõiguse rikkumised Tshetsheenia konfliktis, vastutuse rakendamine

  7. Vene juudid Ameerikas ehk Nõukogude Liidu Jurassic Park / Boris Fishman ; intervjueerinud Priit Hõbemägi

    Index Scriptorium Estoniae

    Fishman, Boris

    2016-01-01

    Intervjuu Tallinna külastanud ameerika kirjaniku Boris Fishmaniga, kes pidas Tallinna ülikoolis loengu ja vestles ameerika vene-juudi kultuuri teemal. Eesti keeles ilmus tema teos "Asenduselu" 2015. aastal

  8. Kokakunsti täiustamine tehnoloogia abiga / Corby Kummer

    Index Scriptorium Estoniae

    Kummer, Corby

    2011-01-01

    Microsofti endise tehnoloogiajuhi Nathan Myhrvoldi eestvõttel töötati välja ja koostati viieköiteline uudseid mõtteid ja tehnoloogiaid sisaldav toitu ja toiduvalmistamist käsitlev teos : Modernist cuisine

  9. Kontserdimajas kõlab ainus juutide reekviem / Ülle Jantson

    Index Scriptorium Estoniae

    Jantson, Ülle

    2009-01-01

    30. oktoobril Pärnu kontserdimajas toimuvast kontserdist, esitusel Eric Zeisli heebreakeelne "Requiem Ebraico" ja Arvo Pärdi teos "Tribute to Caesar", esitajateks Pärnu linnaorkester, kammerkoor Voces Musicales ja solistid

  10. Muutused lastekaitsetöös 2018. aastal / Kadi Lauri

    Index Scriptorium Estoniae

    Lauri, Kadi

    2017-01-01

    Sotsiaalhoolekande seaduse muudatustest, millega luuakse kinnise lasteasutuse teenus, ligipääs lepitusmenetlusele ning sisaldab ka muutusi süüteo toime pannud alaealiste kohtlemisel väär- ja kriminaalmenetluses

  11. [Tänavuse Whitbreadi auhinna pälvis Hilary Spurling biograafia "Matisse the master" eest] / Lauri Eesmaa

    Index Scriptorium Estoniae

    Eesmaa, Lauri

    2006-01-01

    Romaanikategooria auhinna sai Ali Smith romaaniga "The accidental", luulekategoorias Christopher Logue luulekoguga "Cold calls", parima debüüdi tegi Tash Aw romaaniga "The harmony silk factory" ning lasteraamatu kategooria auhinna sai Kate Thompsoni teos "The new policeman"

  12. Understanding the influence of tellurium oxide in front Ag paste for contacting silicon solar cells with homogeneous high sheet resistance emitter

    Science.gov (United States)

    Ebong, Abasifreke; Bezawada, Nirupama; Batchu, Kartheek

    2017-08-01

    This paper investigates TeO2, one of the front Ag paste additives, to understand its role in low contact and gridline resistances for screen-printed Si solar cell. It is concluded that TeO2 aids the reduction of molten glass frit viscosity during contact co-firing. This in turn, leads to uniform flow of molten glass frit, both in the gridline bulk and interface of gridline and SiN x . Therefore, the uniform wetting and etching of SiN x and consequently larger contact area of metal to Si compared to its counterpart without TeO2. Hence, the current transport mechanism from Si to gridline can be said to be both direct and tunneling. The Raman spectra showed a blue shift in the phase of the TeO2 after contact co-firing in the gridline bulk confirming a crystalline γ-TeO2.

  13. Hiina kunstnikud kaebavad Veneetsia biennaali kohtusse / Maria-Kristiina Soomre

    Index Scriptorium Estoniae

    Soomre, Maria-Kristiina, 1978-

    2000-01-01

    1999. a. Veneetsia biennaalil auhinna võitnud hiina kunstniku Cai Guo Qiangi teos "Veneetsia maksukoguja hoov" on Hiinas tekitanud diskussiooni autoriõiguste teemal. Kaalutakse kohtuasja algatamist Cai Guo Qiangi, Harald Szeemanni ja Veneetsia biennaali vastu

  14. Annabel Chongi apokalüptiline raev / Kärt Hellerma

    Index Scriptorium Estoniae

    Hellerma, Kärt, 1956-

    2001-01-01

    Dokumentaalfilm "Seks : Annabel Chongi lugu" ("Sex : Annabel Chong Story") : režissöör, operaator ja kaasprodutsent Gough Lewis : Kanada 1999. Annabel Chongi teo võimalike põhjuste ja postmodernistliku eetika vaatlus

  15. Uudised : Kas Nael lõpetab? Pärt ilma Björkita. Piazzolla esiettekanne Hollandis

    Index Scriptorium Estoniae

    2000-01-01

    Ajakirja "Nael" ilmumisega seotud probleemidest. 1. sept. Tallinnas Kaarli kirikus toimuvast kontserdist, kus tuleb ettekandele Pärdi teos "Which was the son of...". Hollandis tuleb septembris esiettekandele A:Pizzolla senitundmatu kontsert

  16. Uudised : Olari Elts peadirigendiks Riiga. Kitarriöö uudisteosega. Täna algab kirikufestival / Priit Kuusk

    Index Scriptorium Estoniae

    Kuusk, Priit, 1938-

    2001-01-01

    O. Elts allkirjastas 30. juulil lepingu, millega ta saab Läti RSO peadirigendiks. Duo Bagger-Varts esines festivalil "Klaaspärlimäng", esiettekandele tuli J. Räätsa teos "Fragment". IX rahvusvahelisest kirikumuusika festivalist

  17. Harrastuslendurid satuvad tihedamini õnnetustesse / Kadri Bank

    Index Scriptorium Estoniae

    Bank, Kadri

    2008-01-01

    Kui 2006. aastal esitati lennuametile lennunduses toimunud juhtumite kohta 163 ettekannet, siis 2007. aastal oli teateid 205. Vt. samas:¡ Mullu toimus kolm lennuõnnetust. Kommenteerivad Hendrik Agur ja Teo Krüüner

  18. Incorporation of sulfate or selenate groups into oxotellurates(IV). I. Calcium, cadmium, and strontium compounds

    International Nuclear Information System (INIS)

    Weil, Matthias; Shirkhanlou, Mahdi

    2017-01-01

    Seven new mixed oxochalcogenate compounds in the systems M II /X VI /Te IV /O/(H), (M II = Ca, Cd, Sr; X VI = S, Se) were obtained under hydrothermal conditions (210 C, one week). Crystal structure determinations based on single-crystal X-ray diffraction data revealed the compositions Ca 3 (SeO 4 )(TeO 3 ) 2 , Ca 3 (SeO 4 )(Te 3 O 8 ), Cd 3 (SeO 4 )(Te 3 O 8 ), Cd 3 (H 2 O)(SO 4 )(Te 3 O 8 ), Cd 4 (SO 4 )(TeO 3 ) 3 , Cd 5 (SO 4 ) 2 (TeO 3 ) 2 (OH) 2 , and Sr 3 (H 2 O) 2 (SeO 4 )(TeO 3 ) 2 for these phases. Peculiar features of the crystal structures of Ca 3 (SeO 4 )(TeO 3 ) 2 , Ca 3 (SeO 4 )(Te 3 O 8 ), Cd 3 (SeO 4 )(Te 3 O 8 ), Cd 3 (H 2 O)(SO 4 )(Te 3 O 8 ), and Sr 3 (H 2 O) 2 (SeO 4 )(TeO 3 ) 2 are metal-oxotellurate(IV) layers connected by bridging XO 4 tetrahedra and/or by hydrogen-bonding interactions involving hydroxyl or water groups, whereas Cd 4 (SO 4 )(TeO 3 ) 3 and Cd 5 (SO 4 ) 2 (TeO 3 ) 2 (OH) 2 crystallize as framework structures. Common to all crystal structures is the stereoactivity of the Te IV electron lone pair for each oxotellurate(IV) unit, pointing either into the inter-layer space, or into channels and cavities in the crystal structures. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  19. Error Measurements in an Acousto-Optic Tunable Filter Fiber Bragg Grating Sensor System

    Science.gov (United States)

    1994-05-01

    for an ideal AOTF, at 833 and 838 nm using a TeO2 crystal ............................ 33 Figure 3.12. Frequency characteristics of Equation (3.43...multiple channels in an AOTF requires the presence of multiple RF frequencies to establish the complex grating. Since the crystal used in the AOTF ( TeO2 ) is...in germano- silicate glass . This index modulation, Bragg grating, acts as an optical band rejection filter for those wavelengths that meet the Bragg

  20. An Automated System for Accurately Tracking and Measuring Multiple Targets in Six Dimensions

    Science.gov (United States)

    2001-08-01

    diffracted with good efficiency. The deflection medium is a crystal material TeO2 . The power of the electrical signal is 2W. The corresponding diffraction...between 50 MHz and 100 MHz. The acoustooptical deflector used a birefregent TeO2 single crystal as the ultrasonic medium where the light deflection take...pair of glass substrates with sufficient thickness (> 1 mm). The thick glass plate reduces the spatial resolution of the fiberoptic plate. To reduce

  1. V sub 2 O sub 5 -based glasses as cathodes for lithium batteries

    Energy Technology Data Exchange (ETDEWEB)

    Levy, M; Duclot, M J; Rousseau, F [British Columbia Univ., Vancouver (Canada)

    1989-05-01

    The electronic conductivities of glasses in the TeO2-V2O5 and TeO2-V2O5-MoO3 systems have been determined in the 20-200 C temperature range to give simple Arrhenius relationships. Chemical and electrochemical lithium intercalations have been performed, showing that V2O5-based glasses are suitable positive electrode materials for lithium batteries. 20 refs.

  2. Inhibition of Salmonella by thyme essential oil and its effect on microbiological and sensory properties of minced pork meat packaged under vacuum and modified atmosphere.

    Science.gov (United States)

    Boskovic, Marija; Djordjevic, Jasna; Ivanovic, Jelena; Janjic, Jelena; Zdravkovic, Nemanja; Glisic, Milica; Glamoclija, Natasa; Baltic, Branislav; Djordjevic, Vesna; Baltic, Milan

    2017-10-03

    The antibacterial activity of thyme essential oil (TEO) was evaluated against four serovars of Salmonella (S. Enteritidis, S. Typhimurium, S. Montevideo and S. Infantis), experimentally inoculated (10 6 CFU/g) in minced pork, which was treated with different concentrations of the TEO (0.3%, 0.6% and 0.9%) packaged under vacuum or MAP (30%O 2 /50%CO 2 /20% N 2 ) and stored at 3±1°C for 15days. GC-MS analysis of the TEO was performed in order to determine composition, and the predominant constituent was thymol (50.48%), followed by p-cymene and linalool. The minimum inhibitory concentration was determined for each Salmonella serovar studied. Among the tested active compounds, thymol and carvacrol exhibited the greatest inhibitory effect followed by TEO, with minimum inhibitory concentrations of 320 to 640μg/ml. S. Enteritidis was the most sensitive serovar. During the storage period, Salmonella counts in pork were reduced by 1.69-4.05logCFU/g. The influence of TEO on Enterobacteriaceae, lactic acid bacteria and total viable count was determined in control mince with no added Salmonella. The most pronounced antibacterial effect was achieved by the combination MAP and 0.9% TEO. Although the antibacterial activities of all studied concentrations of TEO in pork were evident and significant (P<0.05), sensory analysis showed that 0.3% TEO was the most acceptable to trained panellists. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Air Force/Industry F-35/F-22 Technology Interchange Workshop for Small Business Innovation Research (SBIR): Plenary Session

    Science.gov (United States)

    2007-11-28

    Identification/Solution Process • Senior leader engagement • Joint AFRL/Product center process • Multi-directorate AFRL engagement • PEO/ TEO approval...SPO Primes participation Strategy Driven Process Industry days PEO/ TEO Meeting Jan - May Prioritized Tech Solutions Existing SBIRs SBIR Topics...Electronic parts & components, Frontier now supports the Global Hawk Joint Stars, B-1B, KC -135, C-17, F-15E, & DoD’s Defense Support Program (DSP

  4. Implications of China’s Growing Military Diplomatic Clout for the United States: Cooperation, Competition or Conflict

    Science.gov (United States)

    2009-03-01

    relations with China have indeed improved in recent years. During Defense Minister Teo Chee Hean’s visit to China in November 2005, the two sides agreed to...security issues such as international humanitarian assistance, disaster relief and peacekeeping operations.106 Minister Teo also extended...AIM-92 version; for AH-64D combat helicopters 4 KC -767 Tanker/transport ac 2003 ’ KC -X’ programme; KC -767J version; delivery 2008- 2010 18 RIM

  5. Skipjack tuna (Katsuwonus pelamis) eyeball oil exerts an anti-inflammatory effect by inhibiting NF-κB and MAPK activation in LPS-induced RAW 264.7 cells and croton oil-treated mice.

    Science.gov (United States)

    Jeong, Da-Hyun; Kim, Koth-Bong-Woo-Ri; Kim, Min-Ji; Kang, Bo-Kyeong; Ahn, Dong-Hyun

    2016-11-01

    The effect of tuna eyeball oil (TEO) on lipopolysaccharide (LPS)-induced inflammation in macrophage cells was investigated. TEO had no cytotoxicity in cell viability as compared to the control in LPS induced RAW 264.7 cells. TEO reduced the levels of NO and pro-inflammatory cytokines by up to 50% in a dose-dependent manner. The expression of NF-κB and MAPKs as well as iNOS and COX-2 proteins was reduced by TEO, which suggests that its anti-inflammatory activity is related to the suppression of the NF-κB and MAPK signaling pathways. The rate of formation of ear edema was reduced compared to that in the control at the highest dose tested. In an acute toxicity test, no mice were killed by TEO doses of up to 5000mg/kg body weight during the two week observation period. These results suggested that TEO may have a significant effect on inflammatory factors and be a potential anti-inflammatory therapeutic. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Sensory evaluation and cooking loss of meat of broiler chicken fed probiotics and thyme essential oil

    Directory of Open Access Journals (Sweden)

    Ebrahim Alfaig

    2014-05-01

    Full Text Available A study was conducted to determine the effect of probiotics and thyme essential oil (TEO as feed additives on the sensory attributes, cooking loss and the texture of broiler chicken meat. Day-old broilers Ross 308  (n = 400 were randomly divided into four groups based on the feed supplement as follows: control, probiotics 0.05%, TEO 0.05% and combination of probiotics and TEO, while the fattening period was 42 days. Warner Bratzler shear force, cooking loss and the following sensory attributes (colour, odour, taste, texture, meat decomposing and overall acceptability were tested. The obtained results of the Warner Bratzler shear force show that there was significant different (P < 0.05 between control and TEO group and for the cooking loss there was no significant difference between groups. The descriptive sensory analysis results show that the probiotics group results were somewhat similar to that obtained by control while the TEO group and the combination group results were similar. Regarding the sensory analysis we can state that the combination of the probiotics and TEO have a positive effect on the chicken meat sensory characteristics.

  7. Dehydration of an azeotrope of ethanol/water by sodium carboxymethylcellulose membranes cross-linked with organic or inorganic cross-linker

    Directory of Open Access Journals (Sweden)

    2010-11-01

    Full Text Available To control the swelling of sodium carboxymethylcellulose (CMCNa membranes, mixtures of CMCNa and glutaraldehyde (GA and mixtures of CMCNa as an organic component and tetraethoxysilane (TEOS as an inorganic component were prepared, and CMCNa/GA cross-linked membranes and CMCNa/TEOS hybrid membranes were formed. In the separation of an ethanol/water azeotrope by pervaporation (PV, the effects of the GA or TEOS content on the water/ethanol selectivity and permeability of these CMCNa/GA cross-linked and CMCNa/TEOS hybrid membranes were investigated. Cross-linked and hybrid membranes containing up to 10 wt% GA or 10 wt% TEOS exhibited higher water/ethanol selectivity than CMCNa membrane without any cross-linker. This resulted from both increased density and depressed swelling of the membranes by the formation of a cross-linked structure. The relationship between the structure of the CMCNa/GA cross-linked membranes and CMCNa/TEOS hybrid membranes and their permeation and separation characteristics for an ethanol/water azeotrope during PV is discussed in detail.

  8. Single and combined effects of peppermint and thyme essential oils on productive performance, egg quality traits, and blood parameters of laying hens reared under cold stress condition (6.8 ± 3 °C).

    Science.gov (United States)

    Akbari, Mohsen; Torki, Mehran; Kaviani, Keyomars

    2016-03-01

    This study was conducted to evaluate the effects of adding peppermint essential oil (PEO), thyme essential oil (TEO), or their combination to diet on productive performance, egg quality traits, and blood parameters of laying hens reared under cold stress condition (6.8 ± 3 °C). Feed intake (FI), feed conversion ratio (FCR), egg weight (EW), egg production (EP), and egg mass (EM) were evaluated during the 56-day trial period using 120 Lohmann LSL-lite laying hens. Significant interactions between PEO and TEO on FCR, EP, and EM were observed (P hens fed the diets supplemented by the combined form of PEO and TEO compared to those fed the basal diet. Also, increased EW and FI were observed in the laying hens fed the diet added by PEO compared to the birds fed the basal diet. There were significant interactions between PEO and TEO on the serum level of cholesterol, shell thickness, and Hough unit of egg (P hens fed the diet supplemented by the combined form of PEO and TEO compared to those fed the basal diet. From the results of the present experiment, it can be concluded that diet supplementation by combined form of PEO and TEO could have beneficial effects on performance parameters of hens reared under cold stress condition.

  9. Single and combined effects of peppermint and thyme essential oils on productive performance, egg quality traits, and blood parameters of laying hens reared under cold stress condition (6.8 ± 3 °C)

    Science.gov (United States)

    Akbari, Mohsen; Torki, Mehran; Kaviani, Keyomars

    2016-03-01

    This study was conducted to evaluate the effects of adding peppermint essential oil (PEO), thyme essential oil (TEO), or their combination to diet on productive performance, egg quality traits, and blood parameters of laying hens reared under cold stress condition (6.8 ± 3 °C). Feed intake (FI), feed conversion ratio (FCR), egg weight (EW), egg production (EP), and egg mass (EM) were evaluated during the 56-day trial period using 120 Lohmann LSL-lite laying hens. Significant interactions between PEO and TEO on FCR, EP, and EM were observed ( P hens fed the diets supplemented by the combined form of PEO and TEO compared to those fed the basal diet. Also, increased EW and FI were observed in the laying hens fed the diet added by PEO compared to the birds fed the basal diet. There were significant interactions between PEO and TEO on the serum level of cholesterol, shell thickness, and Hough unit of egg ( P hens fed the diet supplemented by the combined form of PEO and TEO compared to those fed the basal diet. From the results of the present experiment, it can be concluded that diet supplementation by combined form of PEO and TEO could have beneficial effects on performance parameters of hens reared under cold stress condition.

  10. Repairing the Osteochondral Defect in Goat with the Tissue-Engineered Osteochondral Graft Preconstructed in a Double-Chamber Stirring Bioreactor

    Directory of Open Access Journals (Sweden)

    Yang Pei

    2014-01-01

    Full Text Available To investigate the reparative efficacy of tissue-engineered osteochondral (TEO graft for repairing the osteochondral defect in goat, we designed a double-chamber stirring bioreactor to construct the bone and cartilage composites simultaneously in one β-TCP scaffold and observed the reparative effect in vivo. The osteochondral defects were created in goats and all the animals were divided into 3 groups randomly. In groups A, the defect was treated with the TEO which was cultured with mechanical stimulation of stir; in group B, the defect was treated with TEO which was cultured without mechanical stimulation of stir; in groups C, the defect was treated without TEO. At 12 weeks and 24 weeks after operation, the reparative effects in different groups were assessed and compared. The results indicated that the reparative effect of the TEO cultured in the bioreactor was better than the control group, and mechanical stimulation of stir could further improve the reparative effect. We provided a feasible and effective method to construct the TEO for treatment of osteochondral defect using autologous BMSCs and the double-chamber bioreactor.

  11. Estudio por espectroscopía infrarroja de la reacción de hidrólisis y policondensación del IEOS en presencia de PDMS

    Directory of Open Access Journals (Sweden)

    Velasco, M. J.

    2001-02-01

    Full Text Available In this work, we have studied, by FT-IR Spectroscopy, the influence of the molecular weight of organic polymers (polydimethylsiloxane, PDMS in the hydrolysis and polycondensation reactions of tetraethylortosilicate (TEOS in acid medium. Following of the bands located at 880, 1180 and 850 cm- 1, the hydrolysis and selfcondensation of TEOS process and copolymerization between TEOS and PDMS respectively can be studied. The rates of hydrolysis and self-condensation of TEOS are not affected by the presence of the polymer. However , the reaction of copolymerization between TEOS and PDMS decreases when the molecular weight of polymer increase, and this is due to both the diferences in the concentration of silanol end groups of polymer and polymer viscosity. The materials obtained from high molecular weight (18000 and 26000 g/mol have gelification times as TEOS. On the other hand the gelification time decreases when polymers of lower molecular weight ( 550 and 1700 g/mol are used. This work shows that FT-IR Spectroscopy can be applied to investigate the sol-gel reactions.

    En este trabajo se ha estudiado mediante Espectroscopía Infrarroja por transformada de Fourier la influencia del peso molecular de polímeros orgánicos (PDMS en la velocidad de hidrólisis y policondensación de Tetraetilortosilicato (TEOS en medio acuoso ácido. La evolución de las bandas situadas a 880, 1180 y 850 cm- 1 permite estudiar los procesos de hidrólisis, autocondensación y copolimerización respectivamente. La velocidad de hidrólisis y la autocondensación de TEOS no se afecta por la presencia de polímero. Sin embargo la reacción de copolimerización TEOS-PDMS disminuye al aumentar el peso molecular del polímero lo que es debido a diferencias en la concentración de grupos -OH de final de cadena del polímero y a la viscosidad de dichos polímeros. Los materiales obtenidos a partir de PDMS de alto peso molecular (18000 y 26000 g/mol presentan tiempos de

  12. Physical and antibacterial properties of açaí edible films formulated with thyme essential oil and apple skin polyphenols.

    Science.gov (United States)

    Espitia, Paula J P; Avena-Bustillos, Roberto J; Du, Wen-Xian; Chiou, Bor-Sen; Williams, Tina G; Wood, Delilah; McHugh, Tara H; Soares, Nilda F F

    2014-05-01

    Thyme essential oil (TEO) and apple skin polyphenols (ASP) are natural compounds considered as generally recognized as safe by FDA, with biological effects against bacteria and fungi. This work aimed to evaluate physical and antimicrobial properties of açaí edible films formulated with TEO and ASP at 3% and 6% (w/w) individually or combined at 3% (w/w) each. Physical properties studied include mechanical resistance, water vapor permeability (WVP), color, and thermal resistance. Antimicrobial activity against Listeria monocytogenes was determined using the overlay diffusion test. Addition of ASP resulted in improved mechanical properties. TEO at 6% (w/w) resulted in increased elongation. ASP films had significant higher WVP than control film. ASP films were lighter and had more red color than other films. Incorporation of ASP resulted in improved film thermal stability, whereas TEO caused rapid thermal decomposition. Presence of clusters was observed on the surface of films. Addition of ASP resulted in a smoother surface, whereas addition of TEO led to the formation of crater-like pits on the film surface. Açaí edible film incorporated with 6% (w/w) TEO presented the highest antimicrobial activity. However, both antimicrobials are necessary in the açaí films in order to obtain edible films with suitable physical-mechanical properties. The results of the present study showed that TEO and ASP can be used to prepare açaí edible films with adequate physical-mechanical properties and antimicrobial activity for food applications by direct contact. Developed açaí edible films presented antimicrobial activity against L. monocytogenes and good physical-mechanical properties, showing the potential use of açaí edible films in food preservation. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

  13. Site characterization and construction of a controlled shallow test site in central Mexico for archaeological and engineering applications

    Science.gov (United States)

    Rosado-Fuentes, A.; Arango-Galvan, C.; Arciniega-Ceballos, A.; Hernández-Quintero, J. E.; Mendo-Perez, G.

    2017-12-01

    A controlled shallow test site (CSTS) has been constructed at the UNAM Geomagnetic Observatory in Teoloyucan, central Mexico. The objective of the CSTS is to have a controlled place to test new developments and arrays that can be used for archaeological and engineering exploration, as well as to calibrate instruments, train students and for future research. The CSTS was built far enough not to influence the geomagnetic sensors and not be affected by noise sources. Special attention was given to the distribution and geometry of buried materials as well as the instruments used. Before the CSTS was built, a combination of near-surface, non-invasive geophysical techniques was performed to characterize the area of 20 by 32 meters. The methods include magnetometry, electromagnetic induction, ground penetrating radar (GPR), electrical resistivity tomography (ERT) and seismic refraction tomography (SRT). The GPR, SRT and ERT results show relatively flat interfaces. In general, the vertical gradient of the total magnetic field and the electric conductivity have very small variations, showing only one strong magnetic dipole associated to a shallow anomaly. These results indicate that the area is ideal for the construction of the test site. The CSTS consists on buried structures made with different materials and geometries (cubes, cylinders and tubes) commonly used as construction materials in Mexico since Pre-Hispanic times. These materials include concrete, reinforced concrete, wood, brick, adobe, basalt, tezontle and also empty space for controlling responses. The CSTS is versatile enough to be reshaped considering new geometries or materials and to conduct further investigations.

  14. Crystal structure of dilead(II oxochromate(VI oxotellurate(IV

    Directory of Open Access Journals (Sweden)

    Matthias Weil

    2017-06-01

    Full Text Available Reaction of chromium(III precursors with TeO2 in PbF2/PbO melts in air led to oxidation of chromium(III to chromium(VI, whereas tellurium remained its oxidation state of IV. In the resulting title compound, Pb2(CrO4(TeO3, the two types of anions are isolated from each other, hence a double salt is formed. The two independent Pb2+ cations exhibit coordination number nine under formation of very distorted coordination polyhedra [bond-length range = 2.363 (6–3.276 (7 Å]. The oxochromate(VI and oxotellurate(IV anions have tetrahedral and trigonal–pyramidal configurations, respectively. In the crystal structure, (001 layers of metal cations alternate with layers of TeO32− and CrO42− anions along [001], forming a three-dimensional framework structure. Pb2(CrO4(TeO3 is isotypic with its sulfate analogue Pb2(SO4(TeO3 and is comparatively discussed.

  15. Structural and Optical Properties of Lead-Boro-Tellurrite Glasses Induced by Gamma-Ray

    Directory of Open Access Journals (Sweden)

    Azhar Abdul Rahman

    2013-02-01

    Full Text Available Spectrophotometric studies of lead borotellurite glasses were carried out before and after gamma irradiation exposure. The increasing peak on the TeO4 bi-pyramidal arrangement and TeO3+1 (or distorted TeO4 is due to augmentation of irradiation dose which is attributed to an increase in degree of disorder of the amorphous phase. The structures of lead tellurate contain Pb3TeO6 consisting of TeO3 trigonal pyramid connected by PbO4 tetragonal forming a three-dimensional network. The decrease of glass rigidity is due to irradiation process which is supported by the XRD diffractograms results. The decreasing values of absorption edge indicate that red shift effect occur after irradiation processes. A shift in the optical absorption edge attributed to an increase of the conjugation length. The values of optical band gap, Eopt were calculated and found to be dependent on the glass composition and radiation exposure. Generally, an increase and decrease in Urbach’s energy can be considered as being due to an increase in defects within glass network.

  16. Structural and optical properties of lead-boro-tellurrite glasses induced by gamma-ray.

    Science.gov (United States)

    Mustafa, Iskandar Shahrim; Kamari, Halimah Mohamed; Yusoff, Wan Mohd Daud Wan; Aziz, Sidek Abdul; Rahman, Azhar Abdul

    2013-02-04

    Spectrophotometric studies of lead borotellurite glasses were carried out before and after gamma irradiation exposure. The increasing peak on the TeO(4) bi-pyramidal arrangement and TeO(3+1) (or distorted TeO(4)) is due to augmentation of irradiation dose which is attributed to an increase in degree of disorder of the amorphous phase. The structures of lead tellurate contain Pb(3)TeO(6) consisting of TeO(3) trigonal pyramid connected by PbO(4) tetragonal forming a three-dimensional network. The decrease of glass rigidity is due to irradiation process which is supported by the XRD diffractograms results. The decreasing values of absorption edge indicate that red shift effect occur after irradiation processes. A shift in the optical absorption edge attributed to an increase of the conjugation length. The values of optical band gap, E(opt) were calculated and found to be dependent on the glass composition and radiation exposure. Generally, an increase and decrease in Urbach's energy can be considered as being due to an increase in defects within glass network.

  17. Influence of γ-radiation doses on the properties of TeOx: (x=2-3) thin film

    International Nuclear Information System (INIS)

    Dewan, Namrata; Sreenivas, K.; Gupta, Vinay

    2007-01-01

    The influence of γ-ray doses (10-50 Gy) on the optical and electrical properties of radio-frequency sputtered tellurium dioxide (TeO x ) thin film was studied. The composition of the as-deposited TeO x films deposited under 25% oxygen and 100% oxygen in the sputtering gas mixture (Ar+O 2 ) was x=2 and 3, respectively. TeO 3 films were found to be highly sensitive to the γ-radiation doses and the value of optical band gap decrease from 4.18 to 3.56 eV with increasing radiation dose from 10 to 50 Gy. Current-voltage characteristics of the films showed an increase in the value of conductivity with increasing radiation doses. Monotonic decrease in the values of dielectric constant for the deposited films with increase in radiation dose was observed. The effect of γ-ray doses on the properties of TeO x film has been correlated with the rearrangement of the bipyramidal structure of amorphous TeO x thin film

  18. C-di-GMP regulates Pseudomonas aeruginosa stress response to tellurite during both planktonic and biofilm modes of growth

    DEFF Research Database (Denmark)

    Chua, Song Lin; Sivakumar, Krishnakumar; Rybtke, Morten Levin

    2015-01-01

    tellurite (TeO3(2-)) exposure induced the intracellular content of the secondary messenger cyclic di-GMP (c-di-GMP) of Pseudomonas aeruginosa. Two diguanylate cyclases (DGCs), SadC and SiaD, were responsible for the increased intracellular content of c-di-GMP. Enhanced c-di-GMP levels by TeO3(2-) further...... increased P. aeruginosa biofilm formation and resistance to TeO3(2-). P. aeruginosa ΔsadCΔsiaD and PAO1/p(lac)-yhjH mutants with low intracellular c-di-GMP content were more sensitive to TeO3(2-) exposure and had low relative fitness compared to the wild-type PAO1 planktonic and biofilm cultures exposed...... to TeO3(2-). Our study provided evidence that c-di-GMP level can play an important role in mediating stress response in microbial communities during both planktonic and biofilm modes of growth....

  19. Thermal and structural properties of zinc modified tellurite based glasses

    Science.gov (United States)

    Kundu, R. S.; Dhankhar, Sunil; Punia, R.; Dult, Meenakshi; Kishore, N.

    2016-05-01

    Glass system 60 TeO2 - 10 B2O3-(30-x) Bi2O3-x ZnO with mole fraction x = 10, 15, 20, 25 and 30 were synthesized by conventional melt quenching technique under controlled atmospheric conditions. The glass transition temperature (Tg) has been determined using differential scanning Calorimetry (DSC) and its value is observed to increase with increase in ZnO content. This increase may be due to the increase in the concentration of the bridging oxygen (BO) atoms. IR and Raman spectra of the present glass system indicate that ZnO acts as network modifier and exists in ZnO4 units. TeO2 exists as TeO3, TeO4, and TeO3+1 structural units. Bismuth plays the role of network modifier with BiO6 octahedral structural units whereas B2O3 exists in the form of BO3 trigonal and BO4 tetrahedral structural units.

  20. Triple modifier effect on physical, optical and structural properties of boro tellurite zinc lithium glasses

    Science.gov (United States)

    Naresh, P.; Srinivasu, D.; Narsimlu, N.; Ch. Srinivas, Kavitha, B.; Deshpandhe, Uday; Kumar, K. Siva

    2018-05-01

    To investigate physical, optical and structural properties of glass samples of the Quaternary system (60-x)B2O3-xTeO2-10ZnO-30Li2O with x=0,5,10,15, and 20 mol% were prepared by conventional melt quenching technique. XRD confirmed the amorphous nature of all samples. Physical parameters like density, molar volume, Oxygen packing density and etc. calculated. Density of glass samples increased with the increase of TeO2 concentration due to the replacement of lighter B2O3 with heavier TeO2. Optical properties has studied with the help of UV-Visible spectra. Cut off wavelength is increases whereas Eopt and Urbache energies is decreased except intermediate mole fraction of TeO2 at which the triple modifier effect can be observed. Fourier Transform Infrared spectroscopy reveals that the network consists of TeO3 and TeO6 structural units along with BO3 and BO4 units.

  1. Structural and optical study of tellurite-barium glasses

    Science.gov (United States)

    Grelowska, I.; Reben, M.; Burtan, B.; Sitarz, M.; Cisowski, J.; Yousef, El Sayed; Knapik, A.; Dudek, M.

    2016-12-01

    The goal of this work was to determine the effect of barium oxide on the structural, thermal and optical properties of the TeO2-BaO-Na2O (TBN) and TeO2-BaO-WO3 (TBW) glass systems. Raman spectra allow relating the glass structure and vibration properties (i.e. vibrational frequencies and Raman intensities) with the glass composition. Raman spectra show the presence of TeO4 and TeO3+1/TeO3 units that conform with the glass matrix. Differential thermal analysis DTA, XRD measurements have been considered in term of BaO addition. The spectral dependence of ellipsometric angles of the tellurite-barium glass has been studied. The optical measurements were conducted on Woollam M2000 spectroscopic ellipsometer in spectral range of 190-1700 nm. The reflectance and transmittance measurements have been done on spectrophotometer Perkin Elmer, Lambda 900 in the range of 200-2500 nm (UV-VIS-NIR). From the transmittance spectrum, the energy gap was determined.

  2. Fabrication of transparent superhydrophobic silica-based film on a glass substrate

    Science.gov (United States)

    Wang, Shing-Dar; Luo, Shih-Shiang

    2012-05-01

    Tetraethoxysilane (TEOS) was hydrolyzed in an acidic environment and then reacted with hexamethyldisilazane (HMDS) to obtain a superhydrophobic transparent film on a glass substrate. The molar ratios of water and ethanol to TEOS, the pH value of the acidic (or basic) water that is used to hydrolyze TEOS, the heat treatment conditions and other factors were investigated systematically to optimize the transmission through, and the contact angle of water on the film. HMDS (total amount of HMDS/TEOS = 2) was divided into 20 parts, which were added into the sol successively to prevent the sudden production of a large quantity of NH3 in a small area of the sol. The optical and hydrophobic properties of the sol gel continued to change after it had been prepared. The conditions that TEOS was hydrolyzed with acidic water at pH 1.2 at 70 °C and the sol gel was aged at 20 °C for 48 h realized transmission of 90.9% and a water contact angle of 154.3°. No additional surface chemistry modification was needed.

  3. Viscosity properties of tellurite-based glasses

    International Nuclear Information System (INIS)

    Tincher, B.; Massera, J.; Petit, L.; Richardson, K.

    2010-01-01

    The viscosity behavior of glasses with the composition (90-x)TeO 2 -10Bi 2 O 3 -xZnO with x = 15, 17.5, and 20 (TBZ glasses) and 80TeO 2 -(20-y)Na 2 O-yZnO system with y = 0, 5, and 10 (TNZ glasses) have been measured as a function of temperature using a beam-bending (BBV) and a parallel-plate (PPV) viscometer. The structure of the glass' network has been characterized using Raman spectroscopy and has been related to the viscosity temperature behavior and the fragility parameter (m) of the glasses. As the concentration of ZnO in the TBZ system (x) increases, the fragility parameter of the glass increases, whereas it decreases with an increase of the ZnO concentration (y) in the TNZ system. In both glasses, these variations in m have been related to the partial depolymerization of the tellurite network associated with the level of modifier content. The depolymerization of the tellurite network is believed to be the result of a reduction in the number of [TeO 4 ] units and the formation of [TeO 3 ] and [TeO 3+1 ] units that occurs with a change in TeO 2 content in the TBZ system and modifier content in the TNZ system.

  4. Reinforcement of LENRA film by in-situ generated silica produced by sol gel process

    International Nuclear Information System (INIS)

    Mahathir Mohamed; Eda Yuhana Ariffin; Dahlan Mohd; Ibrahim Abdullah

    2008-08-01

    Liquid epoxidised natural rubber acrylate (LENRA) film was reinforced with silica-siloxane structures formed in-situ via sol gel process. Combination of these two components produces organic-inorganic composites. Tetraethylorthosilicate (TEOS) was used as precursor material for silica generation. Sol gel reaction was carried out at different concentrations of TEOS i.e. between 10 and 50 phr. Instrumental analysis was carried out by dynamic mechanical analysis (DMA), thermogravimetry analysis (TGA) and FTIR. It was found that miscibility between organic and inorganic components improved with the presence of silanol groups (Si-OH) and polar solvent i.e. THF, via hydrogen bonding formation between siloxane and LENRA. In this work, the effects of TEOS composition on mechanical properties and interaction that occurs between fillers and matrix have also been studied. It was observed that increasing the concentration of TEOS improved the scratch and stress properties of the film. Morphology study by the scanning electron microscopy (SEM) showed in-situ generated silica particles were homogenous and well dispersed at low concentrations of TEOS. (Author)

  5. Reaction kinetics for preparation of silica film with Stoeber method

    International Nuclear Information System (INIS)

    Shang Mengying; Jiang Xiaodong; Liu Miao; Luo Xuan; Tang Yongjian; Cao Linhong

    2013-01-01

    A new formula was proposed to investigate the relationship between reaction time and tetraethylorthosilicate (TEOS) conversion rate for preparation of silica sol with Stöber method, by studying the reaction kinetics of TEOS hydrolytic process. An appropriate conversion rate was then determined and used to calculate the theoretical optimal reaction time. Meanwhile, silica sols were prepared by sol-gel process using TEOS as precursor and ammonia as catalyst. It was found that the reaction time decreases with an increasing amount of ammonia and water. The values of experimental optimal reaction time were obtained, and agree with the theoretical results (the errors are within 5%), which shows good applicability of our formula. (authors)

  6. Theoretical equation of state for classical fluids. I. Test by perturbation theory

    International Nuclear Information System (INIS)

    Gil-Villegas, A.; Chavez, M.; Del Rio, F.

    1993-01-01

    This paper shows how to construct the theoretical equation of state (TEOS) of a classical simple fluid. The theory relies on the mean collisional diameter and range, and maps the thermodynamical properties of the fluid into those of an equivalent square-well (ESW) fluid of appropriate depth ε , diameter σ and range R. It is shown that the ESW has the same pressure as the fluid of interest. Hence the THEOS of any simple fluid takes the form of a SW EOS of the given ε , σ and R. The theory is applied to a Lennard-Jones (LJ) system in a first-order perturbation. The mapping equation have a physical solution for densities where the SW EOS is accurate; the resulting LJ TEOS agrees very well with the results of computer simulations, and compares favorably with the recent TEOS developed by Song and Mason. (Author). 17 refs, 7 figs, 1 tab

  7. Formation and characterization of vitreous materials prepared by the sol-gel technique

    International Nuclear Information System (INIS)

    Martinez, J.R.; Ruiz, J.F.; Cruz M, J.A. de la; Villasenor G, P.

    1999-01-01

    A full process of preparation and characterization of silica gel, which can be implemented in a experimental course for undergraduate laboratories is presented. Samples of silica gel and sol-gel derived SiO 2 films on glass substrates were fabricated and characterized using atomic force microscopy, Raman and Infrared absorption techniques. Raman and Infrared spectroscopy were used to analyze the local structure. The microstructure characteristics of the films, fabricated by dip-coating, were monitored using atomic force microscopy. The samples were prepared from alcoholic solutions of tetraethylortosilicate (TEOS) keeping the H 2 O/TEOS and Et-OH/TEOS molar ratios constant and equal to 11.66 and 4 respectively. (Author)

  8. Studies on boro cadmium tellurite glasses

    Science.gov (United States)

    Gayathri Pavani, P.; Suresh, S.; Chandra Mouli, V.

    2011-11-01

    To investigate the modification effect of the modifier CdO on boro tellurite glass, a series of glasses with compositions (50 - x) CdO- xTeO 2-50B 2O 3 have been prepared by conventional melt quenching technique. Optical absorption, IR and Raman structural studies are carried out on the glass system. The optical absorption studies revealed that the cutoff wave length and refractive index increase while optical band gap ( Eopt) and Urbach energy decreases with increase of CdO content. The IR and Raman studies revealed that structure of glass network consists of [TeO 3]/[TeO 3+1], [TeO 4], [BO 3], [BO 4] and [Cd-Te] linkages .The compositional dependence of different physical parameters such as density, molar volume, oxygen packing density, optical basicity, have been analyzed and discussed.

  9. In-Ga-Zn-oxide thin-film transistors with Sb2TeOx gate insulators fabricated by reactive sputtering using a metallic Sb2Te target

    International Nuclear Information System (INIS)

    Cheong, Woo-Seok

    2011-01-01

    Using reactive sputtering, we made transparent amorphous Sb 2 TeO x thin films from a metallic Sb 2 Te target in an oxidizing atmosphere. In-Ga-Zn-oxide thin-film transistors (IGZO TFTs) with Sb 2 TeO x gate insulators deposited at room temperature showed a large hysteresis with a counter clockwise direction, which was caused by mobile charges in the gate insulators. The problems of the mobile charges was solved by using Sb 2 TeO x films formed at 250 .deg. C. After the IGZO TFT had been annealed at 200 .deg. C for 1 hour in an O 2 ambient, the mobility of the IGZO TFT was 22.41 cm 2 /Vs, and the drain current on-off ratio was ∼10 8 .

  10. Bioactive glass 45S5 from diatom biosilica

    Directory of Open Access Journals (Sweden)

    Luqman A. Adams

    2017-12-01

    Full Text Available A major draw-back to large scale production of bioactive glasses is the high cost of the standard silica precursor, usually tetraethyl orthosilicate (TEOS. The current study describes a novel sol–gel preparation of 45S5 bioactive glass using diatom biosilica from cultured cells of the diatom, Aulacoseira granulata as substitute to TEOS. The glass formed was characterized using mechanical tester, scanning electron microscopy (SEM, energy dispersive X-ray analysis (EDX, X-ray diffraction (XRD and Fourier transform infrared (FTIR spectroscopy. Results showed that the glass possessed a compressive strength of 3.75 ± 0.18 and formed carbonated hydroxyapatite (HCA within 7 days in simulated body fluid (SBF, attributable to good surface chemistry. The performance of the glass was compared with that of those formed using TEOS. Diatom biosilica could be a potential economically friendly starting material for large scale fabrication of bioactive glasses.

  11. Crystallisation behavior and electronic conductivity of vanadium tellurite glass-ceramics

    DEFF Research Database (Denmark)

    Kjeldsen, Jonas; Yue, Yuanzheng; Rodrigues, A.C.M.

    2012-01-01

    is synthesized via the melt quenching technique, and crystalline 2TeO2-V2O5 is obtained by further heat-treatment of the quenched glass. Both states are confirmed by x-ray diffraction, scanning electron microscopy and differential scanning calorimetry. The redox state of vanadium is controlled via the melting...... and the ability to intercalate lithium-ions, it is a candidate for usage as cathode material. In the present work, we optimize the electronic conductivity of the congruent 2TeO2-V2O5 composition by tuning both the redox state of the vanadium and the overall degree of crystallinity. Amorphous 2TeO2-V2O5...

  12. Atomistic simulations of TeO₂-based glasses: interatomic potentials and molecular dynamics.

    Science.gov (United States)

    Gulenko, Anastasia; Masson, Olivier; Berghout, Abid; Hamani, David; Thomas, Philippe

    2014-07-21

    In this work we present for the first time empirical interatomic potentials that are able to reproduce TeO2-based systems. Using these potentials in classical molecular dynamics simulations, we obtained first results for the pure TeO2 glass structure model. The calculated pair distribution function is in good agreement with the experimental one, which indicates a realistic glass structure model. We investigated the short- and medium-range TeO2 glass structures. The local environment of the Te atom strongly varies, so that the glass structure model has a broad Q polyhedral distribution. The glass network is described as weakly connected with a large number of terminal oxygen atoms.

  13. Electronic Conductivity of Vanadium-Tellurite Glass-Ceramics

    DEFF Research Database (Denmark)

    Kjeldsen, Jonas; Yue, Yuanzheng; Bragatto, Caio B.

    2013-01-01

    In this paper, we investigate the electronic conductivity of 2TeO2-V2O5 glass-ceramics with crystallinity ranging from 0 to 100 wt.%, i.e., from entirely amorphous to completely crystalline. The glass is prepared by the melt quenching technique, and the crystal is prepared by subsequent heat...... spectroscopy. We find similar activation energies for both glass and crystal, implying that they have similar conduction mechanisms, i.e., thermally activated hopping. The electronic conductivity of 2TeO2-V2O5 glass is about one order of magnitude higher than that of the corresponding crystal......, and a percolation phenomenon occurs at a glass fraction of 61 wt.%, increasing from a lower conductivity in the crystal to a higher conductivity in the glass. We explain the behavior of electronic conduction in the 2TeO2-V2O5 glass-ceramics by considering constriction effects between particles as well...

  14. Energy Transfer between Post-Transition Elements & Rare Earths in Oxide & Chalcogenide Glasses.

    Science.gov (United States)

    1979-08-27

    Caird [13]. A calculation of reduced matrix elements of Pr3 in 20 Na O • 80 TeO2 glass [14] showed that they differ slightly from data of ref. [121... glasses Transition (lass 35 ZnO 65 TeO2 20 Na2 O 80 TeO 2 fX 106 fX 106 l.,eas 3a, a) Ia’l. faI f.me.s f al f+ I fal 3 H4 - 3 H6 1.56 1.65 1.12...Rare-Earth Doped Glasses 20. jIST HAEV CCnFn~m ,i cn,on ra e sideit If c."*Ar’ -- ~ 14-r by t?-h.c .: r Intensity parameters, radiative transition

  15. Spectroscopic studies of organic-inorganic composite film cured by low energy electron beam

    International Nuclear Information System (INIS)

    Mahathir Mohamed; Dahlan Mohd; Ibrahim Abdullah; Eda Yuhana Ariffin

    2009-01-01

    Liquid epoxidized natural rubber acrylate (LENRA) film was reinforced with silica particles formed in-situ via sol gel process. Combination of these two components produces organic-inorganic composites. Tetraethyl orthosilicate (TEOS) was used as precursor material for silica generation. Sol gel reactions was carried out at different concentrations of TEOS i.e. between 10 and 50 phr. The compounds that contain silica were crosslinked by electron beam. Structural properties studies were carried out by Fourier Transform Infrared Spectrometer (FTIR). It was found that miscibility between organic and inorganic components improved with the presence of silanol groups (Si-OH) and polar solvent i.e. THF, via hydrogen bonding formation between siloxane and LENRA. Morphology study by the transmission electron microscopy (TEM) and scanning electron microscopy (SEM) showed in-situ generated silica particles were homogenous and well dispersed at any concentrations of TEOS. (author)

  16. Corrosion resistance of siloxane–poly(methyl methacrylate) hybrid films modified with acetic acid on tin plate substrates: Influence of tetraethoxysilane addition

    Energy Technology Data Exchange (ETDEWEB)

    Kunst, S.R.; Cardoso, H.R.P. [LAPEC, Federal University of Rio Grande do Sul – UFRGS, Avenida Bento Gonçalves, 9500 Porto Alegre, RS (Brazil); Oliveira, C.T. [ICET, University Feevale, RS-239, 2755 Novo Hamburgo, RS (Brazil); Santana, J.A.; Sarmento, V.H.V. [Department of Chemistry, Federal University of Sergipe – UFS, Av. Vereador Olímpio Grande s/n, Centro, Itabaiana, SE (Brazil); Muller, I.L. [LAPEC, Federal University of Rio Grande do Sul – UFRGS, Avenida Bento Gonçalves, 9500 Porto Alegre, RS (Brazil); Malfatti, C.F., E-mail: celia.malfatti@ufrgs.br [LAPEC, Federal University of Rio Grande do Sul – UFRGS, Avenida Bento Gonçalves, 9500 Porto Alegre, RS (Brazil)

    2014-04-01

    Highlights: • Siloxane–PMMA film was produced by dip-coating on tin plate substrate. • It was evaluated the influence of (TEOS) addition on siloxane–PMMA hybrid films. • Siloxane–PMMA films without TEOS presented a regular coverage and lowest roughness. • The TEOS addition decrease the corrosion resistance of siloxane–PMMA films. • Siloxane–PMMA without TEOS presented is higher durability in the film wear test. - Abstract: The aim of this paper is to study the corrosion resistance of hybrid films. Tin plate was coated with a siloxane–poly (methyl methacrylate) (PMMA) hybrid film prepared by sol–gel route with covalent bonds between the organic (PMMA) and inorganic (siloxane) phases obtained by hydrolysis and polycondensation of 3-(trimethoxysilylpropyl) methacrylate (TMSM) and polymerization of methyl methacrylate (MMA) using benzoyl peroxide (BPO) as a thermic initiator. Hydrolysis reactions were catalyzed by acetic acid solution avoiding the use of chlorine or stronger acids in the film preparation. The effect of the addition of tetraethoxysilane (TEOS) on the protective properties of the film was evaluated. The hydrophobicity of the film was determined by contact angle measurements, and the morphology was evaluated by scanning electron microscopy (SEM) and profilometry. The local nanostructure was investigated by Fourier transform infrared spectroscopy (FT-IR). The electrochemical behavior of the films was assessed by open circuit potential monitoring, potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) measurements in a 0.05 M NaCl solution. The mechanical behavior was evaluated by tribology. The results highlighted that the siloxane–PMMA hybrid films modified with acetic acid are promising anti-corrosive coatings that acts as an efficient diffusion barrier, protecting tin plates against corrosion. However, the coating properties were affected by the TEOS addition, which contributed for the thickness increase

  17. Electronic, structural, and optical properties of host materials for inorganic phosphors

    International Nuclear Information System (INIS)

    Alemany, Pere; Moreira, Ibério de P.R.; Castillo, Rodrigo; Llanos, Jaime

    2012-01-01

    Highlights: ► We performed a first-principles DFT study of the electronic structures of several wide band gap insulators (La 2 O 3 , La 2 O 2 S, Y 2 O 3 Y 2 O 2 S, La 2 TeO 6 , and Y 2 TeO 6 ) used as host materials for inorganic phosphors. ► The electronic, structural, and optical properties calculated for these compounds are in good agreement with the available experimental data. ► The electronic structure of the M 2 TeO 6 phases exhibits distinct features that could allow a fine tuning of the optical properties of luminescent materials obtained by doping with rare earth metals. - Abstract: A family of large gap insulators used as host materials for inorganic phosphors (La 2 O 3 , La 2 O 2 S, Y 2 O 3 , Y 2 O 2 S, La 2 TeO 6 , and Y 2 TeO 6 ) have been studied by first-principles DFT based calculations. We have determined electronic, structural, and optical properties for all these compounds both at the LDA and GGA levels obtaining, in general, a good agreement with available experimental data and previous theoretical studies. The electronic structure for the M 2 TeO 6 phases, addressed in this work for the first time, reveals some significant differences with respect to the other compounds, especially in the region of the lower conduction band, where the appearance of a group of four isolated oxygen/tellurium based bands below the main part of the La (Y) centered conduction band is predicted to lead to significant changes in the optical properties of the two tellurium containing compounds with respect to the rest of compounds in the series.

  18. Effect of ZnO and PbO/ZnO on structural and thermal properties of tellurite glasses

    International Nuclear Information System (INIS)

    Ramamoorthy, Raj Kumar; Bhatnagar, Anil K

    2015-01-01

    Highlights: • Structural units/linkages variation of TeO 2 -ZnO and TeO 2 -ZnO-PbO glasses was studied. • Structural arrangements of TeO 2 -ZnO glasses are rich in Te-O-Te network. • A mixture of Te-O-Te and Te-O-Pb networks is identified in TeO 2 -ZnO-PbO glasses. • Changes in thermal parameters T g and T o are correlated with the structural variations. • 15PbO and 20PbO samples of TeO 2 -ZnO-PbO glasses show large thermal stability. - Abstract: Two series of glasses, (100 − x)TeO 2 -xZnO (x = 20, 25, 30, 35) and 70TeO 2 -(30 − y)ZnO-yPbO (y = 5, 10, 15, 20), referred as TZ and TZP, respectively, were prepared by a melt quenching technique and characterized by X-ray diffraction (XRD), density, refractive index, Raman scattering and differential scanning calorimetry (DSC) to observe the changes in their properties as a function of ZnO and PbO/ZnO. Variations in individual structural units/linkages in these glasses are derived from the de-convoluted Raman spectra. The glass transition (T g ) and onset of crystallization (T o ) temperatures are determined from DSC isothermal scans. It is observed that the thermal stability (ΔT = T o − T g ) decreases for TZ glasses with increase in x, while it increases for TZP glasses with increase in y. Changes in thermal parameters of these glasses are correlated with the structural variation as a function of ZnO and PbO/ZnO ratio to determine the effect of substitution/addition of metal oxide, ZnO and PbO, to TeO 2 and TeO 2 -ZnO glasses

  19. Preparation of Organic-Inorganic Multifunctional Nanocomposite Coating via Sol-Gel Routes

    International Nuclear Information System (INIS)

    Li Haoying; Chen Yunfa; Ruan Chengxiang; Gao Weimin; Xie Yusheng

    2001-01-01

    The inorganic-organic nanocomposite coatings are prepared on poly(methyl methacrylate) (PMMA) substrate by the spinning technique which involves incorporating homogeneously nanosized ZnO particle into the molecular inorganic-organic hybrid matrices. The hybrid matrices are derived from tetraethoxyasilane (TEOS) and 3-glycidoxypropyltrimethoxyailane (GLYMO). To avoid the destruction of the polymer structure caused by ZnO and modify the interface between nanoparticles and organic groups, ZnO was first surface-coated with SiO 2 from hydrolyzed TEOS using ammonia water as catalyst. The coatings thus obtained are dense, flexible, abrasion resistant and UV absorbent

  20. Fast and long term optical sensors for pH based on sol-gels

    International Nuclear Information System (INIS)

    Wang Enju; Chow, Kwok-Fan; Kwan, Vivian; Chin, Tammy; Wong, Crystal; Bocarsly, Andrew

    2003-01-01

    Long lasting and fast response optical sensor for the detection of pH in the range of 6-12 is described. The sensor is fabricated by spin coating silica sol in the presence of phenol red (PR). The sol is in turn obtained by acidic hydrolysis of tetraethoxysilane (TEOS) and phenyltriethoxysilane (Ph-TriEOS). The performance of the sensor depends on the ratio of Ph-TriOES to TEOS. At the optimal composition, the sensor has a response time of less than 20 s, the response is completely reversible and its life-time is over 12 months

  1. Room-temperature plasma-enhanced chemical vapor deposition of SiOCH films using tetraethoxysilane

    International Nuclear Information System (INIS)

    Yamaoka, K.; Yoshizako, Y.; Kato, H.; Tsukiyama, D.; Terai, Y.; Fujiwara, Y.

    2006-01-01

    Carbon-doped silicon oxide (SiOCH) thin films were deposited by room-temperature plasma-enhanced chemical vapor deposition (PECVD) using tetraethoxysilane (TEOS). The deposition rate and composition of the films strongly depended on radio frequency (RF) power. The films deposited at low RF power contained more CH n groups. The SiOCH films showed high etch rate and low refractive index in proportion to the carbon composition. The deposition with low plasma density and low substrate temperature is effective for SiOCH growth by PECVD using TEOS

  2. Crystal structure of ammonium divanadium(IV,V tellurium(IV heptaoxide

    Directory of Open Access Journals (Sweden)

    William T. A. Harrison

    2014-07-01

    Full Text Available The polyhedral building blocks of the layered inorganic network in the mixed-valence title compound, (NH4(VIVO2(VVO2(TeO3, are vertex-sharing VVO4 tetrahedra, distorted VIVO6 octahedra and TeO3 pyramids, which are linked by V—O—V and V—O—Te bonds, forming double layers lying parallel to (100. The presumed TeIV lone-pairs of electrons appear to be directed inwards into cavities in the double layers. The charge-balancing ammonium cations lie between the layers and probably interact with them via N—H...O hydrogen bonds.

  3. A new method for background rejection with surface sensitive bolometers

    International Nuclear Information System (INIS)

    Nones, C.; Foggetta, L.; Giuliani, A.; Pedretti, M.; Salvioni, C.; Sangiorgio, S.

    2006-01-01

    We report the performance of three prototype TeO 2 macrobolometers, able to identify events due to energy deposited at the detector surface. This capability is obtained by thermally coupling thin active layers to the main absorber of the bolometer, and is proved by irradiating the detectors with alpha particles. This technique can be very useful in view of background study and reduction for the CUORE experiment, a next generation Double Beta Decay search based on TeO 2 macrobolometers and to be installed in the Laboratori Nazionali del Gran Sasso

  4. Summaries of Papers Presented at Photonic Switching Topical Meeting Held in Salt Lake City, Utah on 1-3 March 1989. Technical Digest

    Science.gov (United States)

    1990-01-31

    LiNbO3pltIatet transducers bonded to the side of the TeO2 or GaP bulk crystals. In the integrated devices, the optical phase grating is generated by...deflection efficiency of the TM and TE waves in TeO2 at 1 W of RF power. The reconfiguration time is 50 ns. The worst case crosstalk is less than -24 dB...M1 and M2 consist a 2-D array of small mirrors deposited onto a thin glass substrate. Lenses image the clock, signal, loopback and output spot arrays

  5. Beams 92. Proceedings of the International Conference on High-Power Particle Beams (9th) held in Washington, DC on May 25-29 1992, Volume 3

    Science.gov (United States)

    1992-05-29

    5.66 kG Input cavity: frequency 9.85 GHz mode TEm=o cyclotron harmonic 1 Output cavity: frequency 19.7 GHz Q 744 mode TEo2 cyclotron harmonic 2...spread. (V=80 kV, 1=8 A, cr-2, ThaI buncher cavity with L--1.5k and Q=-5u0, TEo2 catcher cavity with L=-2X and Q--200, L*I=-5.)- Table L Design Parameters...orders of magnitude in comparison with other fusion machines such as Tokamak or glass laser. When the power plant of proton beam fusion is operated with

  6. Analysis and Characterization of an Acousto-Optic Beam Position Control System

    Science.gov (United States)

    2002-07-01

    glass or plastic. This device can be viewed as a medium where light interacts with sound yielding a diffracted light beam. Bragg cells can operate in...by “optical activity” is considered to be very small for TeO2 [2]. The birefringence is due to the fact the index of refraction in for the incident...equations describes behavior of the acousto-optic device. The acoustic velocity can be expressed as follows. azat vvv Θ+Θ= 22222 sincos For TeO2 vt=616 m

  7. Acousto-Optic Applications for Multichannel Adaptive Optical Processor

    Science.gov (United States)

    1992-06-01

    AO cell and the two- channel line-scan camera system described in Subsection 4.1. The AO material for this IntraAction AOD-70 device was flint glass (n...Single-Channel 1.68 (flint glass ) 60,.0 AO Cell Multichannel 2.26 (TeO 2) 20.0 AO Cell Beam splitter 1.515 ( glass ) 50.8 Multichannel correlation was...Tone Intermodulation Dynamic Ranges of Longitudinal TeO2 Bragg Cells for Several Acoustic Power Densities 4-92 f f2 f 3 1 t SOURCE: Reference 21 TR-92

  8. Criteria for Selection of Graded Index Filter Materials Based on an Analysis of Wave Propagation in a Periodic Medium.

    Science.gov (United States)

    1986-01-01

    at 579.1 nm. These materials have high dispersion. 96 TABLE 14 OXIDES IN TELLEJRITE GLASSES .- Add it ive n TeO 2 -BaO TeO2 Wo 3 %*- La 2O 3 1.63...13 PbDeO3 and PbSiO 3 96 14 Oxides in Tellurite Glasses 97 15 Wurtzite Structure 98 16 Rocksalt Structure Chalcogenides 99 17 Zincblende or Sphalerite...alumina in glasses , SiO 2, was reported by Zuther, et al. who studied the glass system Ga 203-GeO 2-’v1 O5.56 The refractive indices of the monoclinic

  9. Neutron scattering techniques for structural studies of amorphous solids

    International Nuclear Information System (INIS)

    Wright, A.C.; Yarker, C.A.; Johnson, P.A.V.; Wedgwood, F.A.

    1976-01-01

    Preliminary data are presented for a series of glasses using some of the special features of neutron diffraction. In vitreous K 2 O x TiO 2 x 2SiO 2 each Ti atom is on average surrounded by 5.2 oxygen atoms at a distance of 1.95 A, whereas the structure of V 2 O 5 x TeO 2 is dominated by distorted TeO 6 octahedra. Features in the magnetic correlation function for vitreous O x 79Fe 2 O 3 x P 2 O 5 occur at the Fe,Fe distance found in crystalline FePO 4 . (orig.) [de

  10. Plasmon-Induced Plasma Spectroscopy

    Science.gov (United States)

    2016-11-10

    is, no new vibrational bands are observed when MB is adsorbed on non- plasmonic surfaces (e.g. glass , platinum, aluminum and gold) and excited with...e.g., TeO2 that we have observed at ∼576.0 eV for samples exposed to air for longer times) are completely absent, and therefore none of the spectral...freshly prepared LB films for which signatures of TeO2 are absent in the XPS spectra. On the other hand, significant blue-shift and spectral broadening

  11. SETA Support for the DARPA Microelectronics Technology Insertion Program of the Microelectronics Technology Office

    Science.gov (United States)

    1992-08-17

    Banerjee of UAH. The Harris study rated Pb2MoO5, GaP, and TeO2 highly. GE is concerned about the availability of Pb2MoO5 and is thus leaning toward using... TeO2 . The buy decision will be made after consideration of both of the aforementioned reports. For the integlatoi, GE is considering Rockwell’s...integrated circuit with polysilicate glass (PSG) optical waveguides, micromechanical membrane switches, and 11 bits of delay. TI’s demonstration array

  12. Scanner Development

    Science.gov (United States)

    1978-07-01

    experience with TeO2 indicates th at 40 percent of the center frequency value is more easily obtainable. The 150 MHz bandwidth corresponds to a center...acousto-optic interaction bandwidth. Substituting the value for n m 2.3 as the average of ne and no of TeO2 and ko - 514.5 nm in Equation (2.2-6), we have L...bandwidth can be fabricated using low cost SF-8 glass . A center frequency of 70 MHz is S, • chosen to produce a reasonably flat scan. The AOND cell

  13. System Design, Implementation, and Evaluation of the Optical Broadband Correlator

    Science.gov (United States)

    1994-09-20

    shear-mode TeO2 , Model No. N45075-6-20, manufactured by Newport Electro- Optic Systems with a length of 75 pjs, acoustic direction 1110], optical...optical aperture (or useful length) TOA of our cells are shown in Table 3. The Bragg cells are shear-mode TeO2 , Model No. N45075-6-20, manufactured by...focusing or integrating (Fourier transform) lens is a laser diode glass doublet Model 06LAI013/076, from Melles Griot. Its focal length is 145 nun at 830

  14. Optical Carry Adder.

    Science.gov (United States)

    1987-03-01

    AOM’s) with the deflected beam as the modulator "on" state. These AOM’s ( TeO2 crystals, manufactured by Newport E.O. Systems) have high deflection...caused by the slow acoustic propagation (4.2 - 105 cm/s for TeO2 ), but this delay can be minimized by placing the laser beam close to the acoustic...dependent jitter in the optical carry to below 1 ns, the total carry path must be less than 30 cm long (or 20 cm in glass , 14 cm in LiNbO 3). Thus, a 32

  15. Optical Interarray Processing.

    Science.gov (United States)

    1980-03-01

    of around 30 frames/sec. One dimensional input transducers such as acousto-optic Bragg cells have much higher frame rates. For example, a TeO2 Bragg...Conventional manufacturing processes such as grinding and polish- ing a glass piece would be difficult if not impossible to apply to the fabrication of such...time-bandwidth product (TBW). An acoustic shear wave in a TeO2 Bragg cell will propagate with a speed of 617 meters/ sec, while the practical physical

  16. Acousto-Optic Processing of 2-D Signals Using Temporal and Spatial Integration.

    Science.gov (United States)

    1986-04-29

    given a, B is in the range Teo2 Bragg cell, with 30 MHz dB bandwidth at 2ោ or a2 <O<m if the images involved are real 820 nm (the laser wavelength...laboratory TeO2 devices with of additive interference, however, DR’ is reduced significantly. Let us up to 70 As delay. Finally, the CCD must have 512 + 64...and b(t) inte- grated over a finite interval T. . Flint glass acoustooptic cells driven at a center fre- - quency of 70 MHz were used in the

  17. Proceedings SPIE: Conference Digest, International Conference on Infrared and Millimeter Waves (18th) Held in Colchester, United Kingdom on 6-10 September 1993. Volume 2104

    Science.gov (United States)

    1993-09-10

    effective dielectric constant appears to decrease upon the substitution of PbO, 1. INRODUCTION In V2 05 - TeO2 glasses several studies on equilibrium... glass increases as TeOg is partially replaced by PbO. Previous studies on V20 5 - TeO2 system 4.5 have reported three Infrared absorption bands at 1010...Laboratory, Dr, K,S. Krishnan Road, New Delhi 110012, India. Th4., REFLECTANCE STUDY OF TM,O. GLASSES - AMemon, M,N.Khan, SAI-Dallal, Department of

  18. Improved Second-Generation 3-D Volumetric Display System. Revision 2

    Science.gov (United States)

    1998-10-01

    computer control, uses infrared lasers to address points within a rare-earth-infused solid glass cube. Already, simple animated computer-generated images...Volumetric Display System permits images to be displayed in a three- dimensional format that can be observed without the use of special glasses . Its...MM 120 nm 60 mm nI POLARIZING I $-"• -’’""BEAMSPLI’i-ER ) 4P40-MHz 50-MHz BW PLRZN i TeO2 MODULATORS TeO2 DEFLECTORS Figure 1-4. NEOS four-channel

  19. Interface Properties and Surface Leakage of HgCdTe Photodiodes.

    Science.gov (United States)

    1980-01-01

    these techniques, we found that (a) the com- position of a 1200 )anodic film is 68% TeO2 , 27% CdO, and 6% HgO, and (b) the cations, especially the Hg...of TeO2 (Fig. 1); (b) irradiation with an electron beam of a few keV energy can convert the surface layer (10-100 1) of (Rg,Cd)Te into CdTe (Fig. 2...remove the scratches. The polishing cloth was secured to a glass olishing disk which is not affected by the corrosive nature of the etch - a 5

  20. Photonics in Switching. Organization of the 1993 Photonics Science Topical Meetings Held in Palm Springs, California on March 15 - 17, 1993. Technical Digest

    Science.gov (United States)

    1993-03-17

    placed on the number of inputs and outputs. For the TeO2 material used in this design, the TB is approximately 1000. Due to the over-resolved...Design of the acoustooptic crossbar switch Figure 2 shows a numerical simulation of the momentum space of an 8 by 8 switch in TeO2 . This switch...results Figure 4 shows switching results from a preliminary demonstration of a three by three switch in a beam-steered flint glass cell. The scope trace

  1. Design and Demonstration of an Acousto-Optic Time-Integrating Correlator with a Large a Parallel Gain

    Science.gov (United States)

    1993-01-01

    Deoxyribose nucleicacid DPP: Digital Post-Processor DREO Detence Research Establishment Ottawa RF: Radio Frequency TeO2 : tellurium dioxide TIC: Time... TeO2 is 620 m/s, a device with a 100-As aperture device is 62-mm long. To take advantage of the full interaction time of these Bragg cells, the whole...INCLUDED IN THE DIGITAL POST-PROCESSOR HARDWARE Characteristics of Bandwidth Center Frequency Bragg Cell glass (bulk 100 MHz 150 MHz interaction) iNbO3

  2. Microwave Magnetic Materials for Radar and Signal Processing Devices - Thin Film and Bulk Oxides and Metals

    Science.gov (United States)

    2007-11-29

    field regime.’ This is V. HIGH FIELD EFFECTIVE LINEWIDTH the applicable situation here. The sample is placed in the center of a TEO ,, cavity with a high...order of 20 /Am. been considered previously. The cavity is the same as in Ref. 1, a TEO ,I cylindrical The above HFE linewidth results also lead to...coupling terms in the equation of motion. The main contri- dt+ Cikck(t) = (OkCk(t) + 60, kC (t) + &A0kCO(t), k * 0. bution to the two magnon

  3. Methods for Reachability-based Hybrid Controller Design

    Science.gov (United States)

    2012-05-10

    approaches for airport runways ( Teo and Tomlin, 2003). The results of the reachability calculations were validated in extensive simulations as well as...UAV flight experiments (Jang and Tomlin, 2005; Teo , 2005). While the focus of these previous applications lies largely in safety verification, the work...B([15, 0],a0)× [−π,π])\\ V,∀qi ∈ Q, where a0 = 30m is the protected radius (chosen based upon published data of the wingspan of a Boeing KC -135

  4. Aerodynamic Performance Predictions of a SA- 2 Missile Using Missile DATCOM

    Science.gov (United States)

    2009-09-01

    transformation that is given by Eqs. (4) and (5). Eqs. (8)–(10) show the formulation in the body and wind axis terminology. 2,0D AC C kC   L (8) 10 cos...by Teo (2008) using Missile LAB code. However, the missile geometry then was set up from a rudimentary drawing and not one that represented a high...provided by MSIC. These particular cases were run forcing turbulent flow with a surface roughness of 0.001016 cm, which was found by Teo (2008) to

  5. Study on stability of a-SiCOF films deposited by plasma enhanced chemical vapor deposition

    International Nuclear Information System (INIS)

    Ding Shijin; Zhang Qingquan; Wang Pengfei; Zhang Wei; Wang Jitao

    2001-01-01

    Low-dielectric-constant a-SiCOF films have been prepared from TEOS, C 4 F 8 and Ar by using plasma enhanced chemical vapor deposition method. With the aid of X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR), the chemical bonding configuration, thermal stability and resistance to water of the films are explored

  6. Творческая встреча с художником

    Index Scriptorium Estoniae

    2015-01-01

    Kohtumisõhtu kunstniku Kristina Normani ja tema videos "Raudne kaar" esineva ukraina aktivisti ja kunstniku Aleftina Kahhidzega. Teos "Raudne kaar" on eksponeeritud ka Tallinna Vene Muuseumis 15. jaanuarist kuni 15. veebruarini avatud näitusel „Reflektsioonid: sissevaade/väljavaade“

  7. Modification of a Phenolic Resin with Epoxy- and Methacrylate-Functionalized Silica Sols to Improve the Ablation Resistance of Their Glass Fiber-Reinforced Composites

    Directory of Open Access Journals (Sweden)

    Yu Hu

    2014-01-01

    Full Text Available Functionalized silica sols were obtained by the hydrolytic condensation of (γ-methacryloxypropyltrimethoxysilane (MPMS, (γ-glycidyloxypropyltrimethoxysilane (GPMS and tetraethoxysilane (TEOS. Three different sols were obtained: MPS (derived from MPMS and TEOS, GPS-MPS (derived from GPMS, MPMS and TEOS, and GPSD (derived from GPMS, TEOS and diglycidyl ether of bisphenol A, DGEBA. These silica sols were mixed with a phenolic resin (PR. Ethylenediamine was used as a hardener for epoxy-functionalized sols and benzoyl peroxide was used as an initiator of the free-radical polymerization of methacrylate-functionalized silica sols. Glass fiber-reinforced composites were obtained from the neat PR and MPS-PR, GPS-MPS-PR and GPSD-PR. The resulting composites were evaluated as ablation resistant materials in an acetylene-oxygen flame. A large increase in the ablation resistance was observed when the PR was modified by the functionalized silica sols. The ablation resistance of the composites decreased as follows: GPSD-PR > MPS-PR > GPS-MPS-PR > PR.

  8. Rein Veidemanni romaan vene keeles

    Index Scriptorium Estoniae

    2015-01-01

    Kirjastus KPD on välja andnud vene keeles Rein Veidemanni 2012. aastal ilmunud romaani "Tund enne igavikku". Marina Tervoneni tõlkes ilmunud teos kannab vene keeles pealkirja "Вечный университет"

  9. Development of artificial articular cartilage

    Indian Academy of Sciences (India)

    Mechanical strength of Poly(vinyl alcohol), PVA is improved up to 35 MPa. Manufacturing method is adopted considering colloidal stability of nano silica particle in PVA sol at specific pH = 1. An adhesive is also prepared from PVA/Si nanocomposite containing 40% TEOS for firm attachment of artificial articular cartilage on ...

  10. Concerts & Opera

    Index Scriptorium Estoniae

    2006-01-01

    Arvo Pärdi teos "Cantus in memoriam Benjamin Britten" esitusel 2. dets. Aldeburghis, Pärdi "Annum per annum" 7. dets. Birminghamis, Kristjan Järvi dirigeerimas 7. dets. Liverpoolis, Neeme Järvi diregeerimas 15. dets. Edinburghis ja 16. dets. Glasgowis

  11. John Cale avaldas memuaarid

    Index Scriptorium Estoniae

    1999-01-01

    Rockbändi "The Velvet Underground" asutajaliige John Cale avaldas oma autobiograafia "What's Welsh for Zen?". Koos biograafiakirjanik Victor Bockrisiga kirjutatud teos räägib 60ndate lõpu kultuurielust New Yorgis, koostööst Andy Warholiga jm.

  12. Olof Palme mõrvar võib olla hoopis tshiillane / Allan Espenberg

    Index Scriptorium Estoniae

    Espenberg, Allan

    2008-01-01

    Rootsi ajakirjanikul Anders Leopoldil ilmus käesoleval aastal teos, mis võtab taas luubi alla Olof Palme mõrva ja tõstatab sellega seoses uusi versioone. Raamatus "Rootsi puu tuleb langetada" seostatakse peaministri mõrva Tšiili tolleaegse kõrgema juhtkonnaga

  13. Belgia väikelinnas keelati Saddami-teemaline kuju / A. F

    Index Scriptorium Estoniae

    A. F

    2006-01-01

    Belgia väikelinnas Middlekerkes keelati ära tšehhi kunstniku David Cerny skulptuur "Saddam Hussein Hai". Teos kujutab aluspükste väel käeraudades endist diktaatorit vedelikus hulpimas. Skulptor on kasutanud motiive inglise skulptori Damien Hirsti teosest "Hai". Kuju on huvilistel võimalik vaadata Ostendi muuseumis

  14. 140 miljonit

    Index Scriptorium Estoniae

    2006-01-01

    Sotheby oksjonil müüdi 20. saj. abstraktse kunsti olulisema autori Jackson Pollocki umbes 2,5 x 1,25 meetri suurune teos "No. 5, 1948". Uus omanik Mehhiko ärimees David Martinez, endine omanik Hollywoodi meelelahutusärimees David Geffen

  15. Anisotropy of acoustic properties in paratellurite

    International Nuclear Information System (INIS)

    Parygin, Vladimir N.

    1996-01-01

    One of the peculiarities of the TeO 2 crystal consists of its strong acoustic anisotropy. This anisotropy demonstrates itself by acoustic energy walk-off and anisotropic distortion of an acoustic beam. Four constants completely characterise the acoustic anisotropy of the medium. In this paper these constants are calculated for various directions of the acoustic beam in crystal. (authors)

  16. Bioactive nanocrystalline wollastonite synthesized by sol–gel ...

    Indian Academy of Sciences (India)

    The sol–gel combustion method was employed to synthesize the nanocrystalline wollastonite by taking the raw eggshell powder as a calcium source and TEOS as a source of silicate. Glycine was .... 94·37% CaCO3, hence in order to prepare 1 M Ca2+ ion solu- ... requires an acid or base catalyst hence the pH of the solu-.

  17. Uudised : EMA uus barokkorel. Olari Elts Soome Raadio SO ees. "Supreme Silence" Saksamaal. Kangro muusika Lätis ja Leedus / Priit Kuusk

    Index Scriptorium Estoniae

    Kuusk, Priit, 1938-

    2001-01-01

    EMA vastvalminud barokkoreli avamispidustustest. O.Elts juhatas 30. apr. Finlandia-talos toimunud kontserdil Soome Raadio SO-d. P.Vähi teos "Supreme Silence" kõlas kahel muusikafestivalil Saksamaal. Läti klaveriduo esitas rahvusvahelisel klaveriduode festivalil Lätis ja Leedus R.Kangro pala "O Sancta Simplicitas!"

  18. Alternative Electrochemical Salt Waste Forms, Summary of FY/CY2011 Results

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Brian J.; McCloy, John S.; Crum, Jarrod V.; Rodriguez, Carmen P.; Windisch, Charles F.; Lepry, William C.; Matyas, Josef; Westman, Matthew P.; Rieck, Bennett T.; Lang, Jesse B.; Pierce, David A.

    2011-12-01

    This report summarizes the 2011 fiscal+calendar year efforts for developing waste forms for a spent salt generated in reprocessing nuclear fuel with an electrochemical separations process. The two waste forms are tellurite (TeO2-based) glasses and sol-gel-derived high-halide mineral analogs to stable minerals found in nature.

  19. Kernel-Based Approximate Dynamic Programming Using Bellman Residual Elimination

    Science.gov (United States)

    2010-02-01

    Redding, Mike Robbins, Frant Sobolic, Justin Teo, Tuna Toksoz, Glenn Tournier, Aditya Undurti, Mario Valenti, Andy Whitten, Albert Wu, and Rodrigo...vector algorithms. Neural Computation, 12(5):1207–1245, 2000. [143] P. Schweitzer and A. Seidman. Generalized polynomial approximation in Markovian

  20. Preparation and characterization of Fe–V/TiO2–SiO2 nanocatalyst ...

    Indian Academy of Sciences (India)

    Administrator

    to silica mole ratio, synthesis temperature and heating rate of calcination on the structure ... 2 wt% of zinc (all on weight percent) supported on TiO2–SiO2 with synthesis temperature of ... (TEOS) and titanium isopropoxide (TIP) have been dis-.

  1. Kontserdikaja / Ave Sopp

    Index Scriptorium Estoniae

    Sopp, Ave

    2003-01-01

    Kontserdist "Tuletrummi tempel" Pärnu kontserdimajas 30. juulil Peeter Vähi kujundatud festivali "Klaaspärlimäng" raames, esitlusel Terry Rile' teos "Pärsia dervishid" (löökpillidele ja orelile) ning Peeter Vähi kantaat "Roheline Tara"

  2. Bioactive nanocrystalline wollastonite synthesized by sol–gel ...

    Indian Academy of Sciences (India)

    The sol–gel combustion method was employed to synthesize the nanocrystalline wollastonite by taking the raw eggshell powder as a calcium source and TEOS as a source of silicate. Glycine was used as a reductant or fuel and nitrate ions present in metal nitrate acts as an oxidizer. The phase purity of the wollastonite was ...

  3. Impact of Sweet Potato Starch-Based Nanocomposite Films Activated With Thyme Essential Oil on the Shelf-Life of Baby Spinach Leaves

    Directory of Open Access Journals (Sweden)

    Aseel Issa

    2017-06-01

    Full Text Available Salmonella Typhimurium (S. Typhi and Escherichia coli (E. coli have been responsible for an increasing number of outbreaks linked to fresh produce, such as baby spinach leaves, in the last two decades. More recently, antimicrobial biodegradable packaging systems have been attracting much attention in the food packaging industry as eco-friendly alternatives to conventional plastic packaging. The objective of this study was to evaluate the effect of antibacterial nanocomposite films on inoculated spinach leaves and on the sensory properties of these leaves during eight days of refrigerated storage. In this study, an antibacterial film comprised of sweet potato starch (SPS, montmorillonite (MMT nanoclays and thyme essential oil (TEO as a natural antimicrobial agent was developed. Our results showed that the incorporation of TEO in the film significantly (p < 0.05 reduced the population of E. coli and S. Typhi on fresh baby spinach leaves to below detectable levels within five days, whereas the control samples without essential oil maintained approximately 4.5 Log colony forming unit (CFU/g. The sensory scores for spinach samples wrapped in films containing TEO were higher than those of the control. This study thus suggests that TEO has the potential to be directly incorporated into a SPS film to prepare antimicrobial nanocomposite films for food packaging applications.

  4. Gamma Radiation Dosimetry Using Tellurium Dioxide Thin Film Structures

    Directory of Open Access Journals (Sweden)

    Olga Korostynska

    2002-08-01

    Full Text Available Thin films of Tellurium dioxide (TeO2 were investigated for γ-radiation dosimetry purposes. Samples were fabricated using thin film vapour deposition technique. Thin films of TeO2 were exposed to a 60Co γ-radiation source at a dose rate of 6 Gy/min at room temperature. Absorption spectra for TeO2 films were recorded and the values of the optical band gap and energies of the localized states for as-deposited and γ-irradiated samples were calculated. It was found that the optical band gap values were decreased as the radiation dose was increased. Samples with electrical contacts having a planar structure showed a linear increase in current values with the increase in radiation dose up to a certain dose level. The observed changes in both the optical and the electrical properties suggest that TeO2 thin film may be considered as an effective material for room temperature real time γ-radiation dosimetry.

  5. Temperature dependence of elastic properties of paratellurite

    International Nuclear Information System (INIS)

    Silvestrova, I.M.; Pisarevskii, Y.V.; Senyushenkov, P.A.; Krupny, A.I.

    1987-01-01

    New data are presented on the temperature dependence of the elastic wave velocities, elastic stiffness constants, and thermal expansion of paratellurite. It is shown that the external pressure appreciably influences the elastic properties of TeO 2 , especially the temperature dependence of the elastic modulus connected with the crystal soft mode. (author)

  6. Size Controlled Synthesis of Tellurium Nanorices by Galvanic Displacement Reaction of Aluminum

    International Nuclear Information System (INIS)

    Wu, Tingjun; Myung, Lawrence Youngjae; Zhang, Miluo; Lee, Kyu-Hwan; Lee, Yeheun Laura; Lim, Hyo-Ryong; Kim, Bum Sung; Choa, Yong-Ho; Myung, Nosang V.

    2015-01-01

    ABSTRACT: Tellurium nanostructures were synthesized by galvanic displacement reaction (GDR) of aluminum in an alkaline solution containing TeO 3 2− ions. Due to negative redox potential of Al/AlO 2 − (i.e., −2.50 V vs. sat. Ag/AgCl), TeO 3 2− (+IV) can be reduced to Te 2 2− (-I) and Te 2− (-II), which resulted in the deposition of Te (0) nanostructures in the solution via chemical reaction between Te 2 2− or Te 2− and TeO 3 2− . The deposition mechanism led to the formation of unique “rice-like” nanostructures in the solution instead of branched structures on the substrate. The sharp tips of the “rice-like” nanostructures may be attributed to the high density of surface charges at the tips. The morphology, diameter and aspect ratio of Te “rice-like” nanostructures were altered by the TeO 3 2− concentration, solution pH, reaction time and the reaction temperature. Electrochemical analytical methods, including open circuit potential (OCP) and linear polarizations (LPs), were used to investigate the reaction mechanisms. The enhancement of piezoelectric constant (d 11 ) of nanorices at small diameter was probably due to a flexoelectric effect

  7. Meistri kutsumine / Taavi Talve, Indrek Köster ; intervjueerinud Elena Šmakova

    Index Scriptorium Estoniae

    Talve, Taavi

    2009-01-01

    Loomingulise ühenduse Johnson ja Johnson - Taavi Talve, Indrek Köster - näitus "Meistri kutsumine" Hobusepea Galeriis 27. aprillini. Autorid 2006. aastal alustatud Paldiski linnaruumi ja selle elanikke kaasavast projektist, mille lõppeesmärk on luua Paldiskisse Amandus Adamsoni skulptuur. Linnaelanike lemmikuks osutus teos "Laeva viimne ohe", mille savist suurenduse modelleerib Mare Mikof

  8. Alternative Electrochemical Salt Waste Forms, Summary of FY/CY2011 Results

    International Nuclear Information System (INIS)

    Riley, Brian J.; McCloy, John S.; Crum, Jarrod V.; Rodriguez, Carmen P.; Windisch, Charles F.; Lepry, William C.; Matyas, Josef; Westman, Matthew P.; Rieck, Bennett T.; Lang, Jesse B.; Pierce, David A.

    2011-01-01

    This report summarizes the 2011 fiscal+calendar year efforts for developing waste forms for a spent salt generated in reprocessing nuclear fuel with an electrochemical separations process. The two waste forms are tellurite (TeO2-based) glasses and sol-gel-derived high-halide mineral analogs to stable minerals found in nature.

  9. Uudised : Isaac Hayes loobub koka rollist. Bergeni festival soomestub

    Index Scriptorium Estoniae

    2006-01-01

    Satiirilises animaseriaalis "South Park" mustanahalise koolikoka rollis lugenud soulilauljast Isaak Hayes'ist. 24. maist 6. juunini kestval Bergeni kultuurifestivalil Norras tulevad esitusele Jean Sibeliuse sümfooniad, Magnus Lindbergi heliteosed, koreograaf Tomi Paasoneni teos "Olotila" ja pianist Juho Pohjoneni klverikontsert

  10. Baltische Musik für Streichorchester (Vol. 2) / Hans-Christian Dadelsen

    Index Scriptorium Estoniae

    Dadelsen, Hans-Christian

    1995-01-01

    Uuest heliplaadist "Baltische Musik für Streichorchester (Vol. 2). Ostrobothnian Chamber Orchestra, Juha Kangas". Finlandia/East West Records CD 4509-9789-2 (WD: 64'34") Plaadil ka Erkki-Sven Tüüri teos "Insula Deserta"

  11. Fulltext PDF

    Indian Academy of Sciences (India)

    Unknown

    High purity Bi2O3 and TeO2 were used as starting materials and were mixed thoroughly with molar ... Platinum crucible was fabricated with a seed well of 10 mm in diameter and several .... petition of these nuclei in the folded seed well.

  12. Soomlaste oma Eesti ajalugu / Heino Arumäe, Mati Graf, Priit Raudkivi

    Index Scriptorium Estoniae

    Arumäe, Heino

    2008-01-01

    Rets. rmt.: Seppo Zetterberg. Viron historia. Helsinki, 2007. Suomalaisen Kirjallisuuden Seuran Toimituksia ; 1118. Tegemist on mahukaima mitteeestlase sulest ilmunud Eesti ajalugu käsitleva teosega. Teos on mõeldud soome lugejale. Rikkalikult illustreeritud raamatu paljude fotode autor on Seppo Zetterberg ise

  13. DSC, Raman and impedance spectroscopy studies on the xB2O3 - (90 - x)TeO2 - 10TiO2 (where x = 0 to 50 mol%) glass system

    Science.gov (United States)

    Sripada, Suresh; Rani, D. Esther Kalpana; Upender, G.; Pavani, P. Gayathri

    2013-03-01

    Titanium boro tellurite glasses in the xB2O3 -(90- x) TeO2 - 10TiO2 (where x = 0 to 50 mol%) system were prepared by using the conventional melt-quenching technique. Glass transition temperatures were measured with differential scanning calorimetry (DSC) and found to be in the range of 300-370 °C. The Raman spectra showed a cleavage of the continuous TeO4 (tbp) network by breaking of the Te-O-Te linkages. The relative transition of TeO4 - groups to TeO3 - groups is accompanied by a change in the oxygen coordination of the boron from 3 to 4 (BO3 - to BO4 -). The impedance plots Z″( ω) versus Z'( ω) for all the glass samples were recorded and found to exhibit a single circle. The AC conductivity of all glass samples was studied in the frequency range from 100 Hz to 1 MHz and in the temperature range from room temperature (RT) to 375 °C. The AC conductivity decreased by about one order in magnitude with increasing B2O3 content. The conductivity was found to be on the order of 10-4.5 to 10-6 (Ωcm)-1 at 375 °C and 1 MHz for 10 mol% and 50 mol% B2O3 contents, respectively. The relaxation behavior in these glass samples is discussed based on the complex modulus and impedance data.

  14. Self-assembly of the hydrogel polymer chain consisting of chitosan and chondroitin sulphate in the presence of theophylline;Propriedades de higrogeis constituidos de quitosana e sulfato decondroitina na presenca de teofilina intumescidos em diferentes pHs

    Energy Technology Data Exchange (ETDEWEB)

    Lopes, Lais C.; Piai, Juliana F.; Fajardo, Andre R.; Rubira, Adley F.; Muniz, Edvani C., E-mail: ecmuniz@uem.b [Universidade Estadual de Maringa (GMPC/UEM), PR (Brazil). Grupo de Materiais Polimericos e Compositos

    2009-07-01

    In this work, polyelectronic complex (PEC) consisting of two polysaccharides were developed. One is chitosan (QT), cationic polymer, produced by the chitin deacetylation and the other is chondroitin sulphate (CS), anionic polymer, extracted from bovine or porcine aorta. The PECs were prepared in the presence of theophylline (TEO) for evaluating the influence of this drug in the polymer chains reorganization, as well as, studying the mechanical properties and release of SC and TEO in aqueous solutions on different pH conditions. By the obtained results, it was observed that the 84QT/15SC/TEO (% in weight) hydrogel is pH responsive because the CS releasing is more effective at pH 8, while the release of the TEO is higher at pH 2. The hydrogel showed mechanical properties more resistant to pH 2, 8 and 10 and this was attributed to interactions between the polymer chains. Finally, the X-rays profile showed the presence of peaks associated to reorganization of the chains in the hydrogel is at times larger than the hydrogel in the absence of solute. (author)

  15. Investigations on the system Te/O/Br

    International Nuclear Information System (INIS)

    Oppermann, H.; Kunze, G.; Wolf, E.; Titov, V.A.; Kokovin, G.A.

    1978-01-01

    The melting point diagram of the system TeBr 4 -TeO 2 was obtained by total pressure measurements and DTA measurements. A congruent melting composition Te 6 O 11 Br 2 exists, the melting point is 570 0 C. The enthalpy of formation and the standard entropy of the species TeOBr 2 ,g was derived from measurements of the total pressure over Te 6 O 11 Br 2 /TeBr 4 and from the transport behaviour of the TeO 2 with Br 2 . From the decomposition-pressure measurements over Te 6 O 11 Br 2 /TeO 2 follow the partial pressures. The enthalpy of formation ΔH 0 (Te 6 O 11 Br 2 ,f,298) -453.5 kcal/Mol was obtained from the enthalpy of solution. The transport-behaviour of TeO 2 with HBr, TeBr 4 and Br 2 and that of Te 6 O 11 Br 2 is clear with the thermodynamic data of TeOBr 2 . (author)

  16. Vabatrupp näitas meeleheite hiiglasi / Margit Tõnson

    Index Scriptorium Estoniae

    Tõnson, Margit, 1978-

    2005-01-01

    11. märtsil esietendus teatris NO98 ja Sine Loco (A. Türnpu projekt) koostöös lavastus "Inimese teekond", mille lähtematerjaliks on J. Bunyani religioosne teos "Palveränduri tee". Lavastaja ja kokkupanija A. Türnpu

  17. Pääsemine? / Andrus Norak

    Index Scriptorium Estoniae

    Norak, Andrus, 1958-2011

    2005-01-01

    11. märtsil esietendus teatris NO98 ja Sine Loco (A. Türnpu projekt) koostöös lavastus "Inimese teekond", mille lähtematerjaliks on J. Bunyani religioosne teos "Palveränduri tee". Lavastaja ja kokkupanija A. Türnpu

  18. Aitajaid sel teekonnal pole / Madli Pesti

    Index Scriptorium Estoniae

    Pesti, Madli, 1980-

    2005-01-01

    11. märtsil esietendus teatris NO98 ja Sine Loco (A. Türnpu projekt) koostöös lavastus "Inimese teekond", mille lähtematerjaliks on J. Bunyani religioosne teos "Palveränduri tee". Lavastaja ja kokkupanija A. Türnpu

  19. Inimese teekond valguses ja varjus / Karina Talts

    Index Scriptorium Estoniae

    Talts, Karina

    2005-01-01

    11. märtsil esietendus teatris NO98 ja Sine Loco (A. Türnpu projekt) koostöös lavastus "Inimese teekond", mille lähtematerjaliks on J. Bunyani religioosne teos "Palveränduri tee". Lavastaja ja kokkupanija A. Türnpu

  20. Effect of polarizable lone pair cations on the second-harmonic generation (SHG) properties of noncentrosymmetric (NCS) Bi(2-x)Y(x)TeO₅ (x = 0-0.2).

    Science.gov (United States)

    Jo, Hongil; Kim, Yeong Hun; Lee, Dong Woo; Ok, Kang Min

    2014-08-14

    Y(3+)-doped noncentrosymmetric (NCS) bismuth tellurite materials, Bi(2-x)Y(x)TeO5 (x = 0, 0.1, and 0.2), have been synthesized through standard solid-state reactions and structurally characterized by powder neutron diffraction. The reported NCS materials crystallize in the orthorhombic space group Abm2 (no. 39), and exhibit pseudo-three-dimensional frameworks that are composed of BiO3, BiO5, and TeO3 polyhedra. Detailed diffraction studies show that the cell volume of Bi(2-x)Y(x)TeO5 decreases with an increasing amount of Y(3+)on the Bi(3+) sites. However, no ordering between Bi(3+) and Y(3+) was observed in the Bi(2-x)Y(x)TeO5. Powder second-harmonic generation (SHG) measurements, using 1064 nm radiation, reveal that Bi2TeO5, Bi(1.9)Y(0.1)TeO5, and Bi(1.8)Y(0.2)TeO5 exhibit SHG efficiencies of approximately 300, 200, and 60 times that of α-SiO2, respectively. The reduction in SHG for Y(3+)-doped materials is consistent with the lack of net moment originating from polyhedra with a polarizable Bi(3+) cation.

  1. Töötajate varaline vastutus : [bakalaureusetöö] / Karin Lehari ; Tartu Ülikool, õigusteaduskond ; juhendaja: Merle Muda

    Index Scriptorium Estoniae

    Lehari, Karin

    1999-01-01

    Kahju tekitamisest tulenev kahju hüvitamine, töötaja poolt tekitatud kahju hüvitamise tingimused - varalise kahju olemasolu, töötaja teo õigusvastasus, põhjuslik seos, süü ja süü vormid, tööandja vastutus töötaja poolt kolmandatele isikutele tekitatud kahju eest

  2. Gilbert ja George lasevad oma kunstiteose alla laadida

    Index Scriptorium Estoniae

    2007-01-01

    9.05.2007 öösel on kõigil soovijail võimalik tasuta interneti vahendusel omandada Londonis tegutseva kunstnikepaari Gilbert & George (Gilbert Proesch ja George Passmore) teos "Planed". Aadressid: www.bbc.co.uk/imagine ja www.guardian.co.uk/art

  3. Tuntud ja tundmatud meistrid 4 / Helena Risthein

    Index Scriptorium Estoniae

    Risthein, Helena, 1954-

    2003-01-01

    Kadrioru lossis eksponeeritud teos "Madonna puuviljapärja keskel" koosneb kahest maalitahvlist, kuna tolleaegsed kunstnikud spetsialiseerusid kitsale erialale. Pieter Franzs. de Grebber (1600-1653) maalis Maarja Kristus-lapsega ja Frans Ykens (1601-1693) Maarjat ümbritseva puuviljapärja

  4. Surface texture modification of spin-coated SiO2 xerogel thin films ...

    Indian Academy of Sciences (India)

    hydrolysis and condensation of tetraethylorthosilicate (TEOS) with ethanol as a solvent. Further, the deposited thin films were ... termed as hydrolysis and condensation that occur simultane- ously in the formation of silica films. ... rial leads to capillary tensions, which destroy the structure of silica (Naik and Ghosh 2009).

  5. Gratitud en la Psicología Positiva

    Directory of Open Access Journals (Sweden)

    Natalia Moyano

    2015-09-01

    Full Text Available El trabajo analiza brevemente los desarrollos relacionados con la gratitud en el marco de la Psicología Positiva, sus definiciones, elementos, aportes teóricos y efectos. Se describen aquellos aspectos de la gratitud que requieren investigación y se proponen elementos de análisis del tema. 

  6. Effects of Thymol and Carvacrol, Constituents of Thymus vulgaris L. Essential Oil, on the Inflammatory Response

    Directory of Open Access Journals (Sweden)

    Fernanda Carolina Fachini-Queiroz

    2012-01-01

    Full Text Available Thyme (Thymus vulgaris L., Lamiaceae is an aromatic and medicinal plant that has been used in folk medicine, phytopharmaceutical preparations, food preservatives, and as an aromatic ingredient. The effect of Thymus vulgaris essential oil (TEO and its isolated constituents thymol and cavacrol (CVL were studied in the following experimental models: ear edema, carrageenan-induced pleurisy, and chemotaxis in vitro. In the pleurisy model, TEO, CVL, and thymol significantly inhibited inflammatory edema. However, only TEO and CVL inhibited leukocyte migration. In the in vitro chemotaxis experiment, CVL inhibited leukocyte migration, whereas thymol exerted a potent chemoattractant effect. In the ear edema model, CVL (10 mg/ear, applied topically, reduced edema formation, exerting a topical anti-inflammatory effect. Thymol did not reduce edema formation but rather presented an irritative response, probably dependent on histamine and prostanoid release. Our data suggest that the antiinflammatory effects of TEO and CVL are attributable to the inhibition of inflammatory edema and leukocyte migration.

  7. NYYD Ensemble ja Riho Sibul / Anneli Remme

    Index Scriptorium Estoniae

    Remme, Anneli, 1968-

    2001-01-01

    Gavin Bryarsi teos "Jesus' Blood Never Failed Me Yet" NYYD Ensemble'i ja Riho Sibula esituses 27. detsembril Pauluse kirikus Tartus ja 28. detsembril Rootsi- Mihkli kirikus Tallinnas. Kaastegevad Tartu Ülikooli Kammerkoor (Tartus) ja kammerkoor Voces Musicales (Tallinnas). Kunstiline juht Olari Elts

  8. Eesti põllumajanduse ja maaelu hävitamise lugu / Villu Reiljan

    Index Scriptorium Estoniae

    Reiljan, Villu, 1953-

    2001-01-01

    Raamatust: Decollectivisation, destruction and disillusionment. A community study in Southern Estonia. Tallinn: Jyväskylä, 2001. Teos käsitleb Eesti põllumajanduse allakäiku viimase 10 a. jooksul. Uuring Kanepi valla näitel. Autor: ERL. Parlamendisaadik

  9. Sol-gel synthesis of magnesium oxide-silicon dioxide glass compositions

    Science.gov (United States)

    Bansal, Narottam P.

    1988-01-01

    MgO-SiO2 glasses containing up to 15 mol pct MgO, which could not have been prepared by the conventional glass melting method due to the presence of stable liquid-liquid immiscibility, were synthesized by the sol-gel technique. Clear and transparent gels were obtained from the hydrolysis and polycondensation of silicon tetraethoxide (TEOS) and magnesium nitrate hexahydrate when the water/TEOS mole ratio was four or more. The gelling time decreased with increase in magnesium content, water/TEOS ratio, and reaction temperature. Magnesium nitrate hexahydrate crystallized out of the gels containing 15 and 20 mol pct MgO on slow drying. This problem was partially alleviated by drying the gels quickly at higher temperatures. Monolithic gel samples were prepared using glycerol as the drying control additive. The gels were subjected to various thermal treatments and characterized by several methods. No organic groups could be detected in the glasses after heat treatments to approx. 800 C, but trace amounts of hydroxyl groups were still present. No crystalline phase was found from X-ray diffraction in the gel samples to approx. 890 C. At higher temperatures, alpha quartz precipitated out as the crystalline phase in gels containing up to 10 mol pct MgO. The overall activation energy for gel formation in 10MgO-90SiO2 (mol pct) system for water/TEOS mole ratio of 7.5 was calculated to be 58.7 kJ/mol.

  10. Leren bedrijfseconomische problemen op te lossen door het maken van vakspecifieke schema’s

    NARCIS (Netherlands)

    Slof, Bert; Erkens, Gijsbert; Kirschner, Paul A.

    2010-01-01

    Slof, B., Erkens, G., & Kirschner, P. A. (2010). Leren bedrijfseconomische problemen op te lossen door het maken van vakspecifieke schema’s [Learning to solve business-economics problems through constructing domainspecific diagrams]. Tijdschrift voor het Economisch Onderwijs (TEO), 110(4), 226–230.

  11. Sol-Gel synthesis of MgO-SiO2 glass compositions having stable liquid-liquid immiscibility

    Science.gov (United States)

    Bansal, Narottam P.

    1987-01-01

    MgO-SiO2 glasses containing up to 15 mol % MgO, which could not have been prepared by the conventional glass melting method due to the presence of stable liquid-liquid immiscibility, were synthesized by the sol-gel technique. Clear and transparent gels were obtained from the hydrolysis and polycondensation of silicon tetraethoxide (TEOS) and magnesium nitrate hexahydrate when the water/TEOS mole ratio was four or more. The gelling time decreased with increase in magnesium content, water/TEOS ratio, and reaction temperature. Magnesium nitrate hexahydrate crystallized out of the gels containing 15 and 20 mol % MgO on slow drying. This problem was partially alleviated by drying the gels quickly at higher temperatures. Monolithic gel samples were prepared using glycerol as the drying control additive. The gels were subjected to various thermal treatments and characterized by several methods. No organic groups could be detected in the glasses after heat treatments to approx. 800 C, but trace amounts of hydroxyl groups were still present. No crystalline phase was found from X-ray diffraction in the gel samples to approx. 890 C. At higher temperatures, alpha quartz precipitated out as the crystalline phase in gels containing up to 10 mol % MgO. The overall activation energy for gel formation in 10MgO-90SiO2 (mol %) system for water/TEOS mole ratio of 7.5 was calculated to be 58.7 kJ/mol.

  12. Structural characterization of tellurite glasses doped with transition metal oxides using Raman spectra and ab initio calculations.

    Science.gov (United States)

    Mohamed, Tarek A; Shaltout, I; Al Yahyaei, K M

    2006-05-01

    Systems of iron tellurite glasses were prepared by melt quenching with compositions of [85%TeO2+5%Fe2O3+10%TMO], where transition metal oxides (TMO) are TiO2, V2O5, MnO, CoO, NiO and CuO. Furthermore, the main structural units of these samples have been characterized by means of Raman spectra (150-1200 cm(-1)) as well as wavenumber predictions by means of Gaussian 98 ab initio calculations for the proposed site symmetries of TeO4(4-) triagonal bipyramid (C2v) and Te2O7(6-) bridged tetrahedra (Cs and C1). Aided by normal coordinate analysis, calculated vibrational frequencies, Raman scattering activities, force constants in internal coordinates and potential energy distributions (PEDs), revised vibrational assignments for the fundamental modes have been proposed. The main structural features are correlated to the dominant units of triagonal bipyramid (tbp) or bridged tetrahedral (TeO3+1 binds to TeO3 through TeOTe bridge; corner sharing). Moreover, the Raman spectra of the investigated tellurites reflect a structural change from tbp (coordination number is four) to triagonal pyramidal (coordination number is three).

  13. Spectral and Polarimetric Analysis of Hyperspectral Data Collected by an Acousto-Optic Tunable Filter System

    Science.gov (United States)

    1993-09-23

    dioxide ( TeO2 ) crystal which splits a beam of light entering the sensor into a set of two narrow band, orthogonally polarized images for each...See Figure 3) These laws hold true for Light ry V m .Li t ray , &o r air RefairRefractive lade: a, )’i i .- t 1 V Refractive inaex n’ Glass or

  14. Rare-Earth Oxide Ion (Tm3+, Ho3+, and U3+) Doped Glasses and Fibres for 1.8 to 4 Micrometer Coherent and Broadband Sources

    National Research Council Canada - National Science Library

    Richards, Billy; Shen, Shaoxiong; Jha, Animesh

    2006-01-01

    ... (TeO2), fluorine-containing silicate (SiOF2) and germanate (GeOF2) glass hosts for each dopant by characterising the spectroscopic properties, including absorption and emission cross-sections and the lifetimes of the lasing levels...

  15. Optical and spectroscopic investigation on Calcium Borotellurite glass system

    Science.gov (United States)

    Paz, E. C.; Lodi, T. A.; Gomes, B. R. A.; Melo, G. H. A.; Pedrochi, F.; Steimacher, A.

    2016-05-01

    In this work, the glass formation in Calcium Borotellurite (CBTx) system and their optical properties were studied. Six glass samples were prepared by melt-quenching technique and the samples obtained are transparent, lightly yellowish, without any visible crystallites. The results showed that TeO2 addition increases the density, the electronic polarizability and, consequently, the refractive index. The increase of electronic polarizability and optical basicity suggest that TeO2 addition increases the non-bridging oxygen (NBO) concentration. The increase of TeO2 shifts the band edge to longer wavelength owing to increase in non-bridging oxygen ions, resulting in a linear decrease of optical energy gap. The addition of TeO2 increases the temperature coefficient of the optical path length (dS/dT) in room temperature, which are comparable to phosphate and lower than Low Silica Calcium Alumino Silicate (LSCAS) glasses. The values of dS/dT present an increase as a function of temperature for all the samples measured. The results suggest that CBTx is a good candidate for rare-earth doping and several optical applications.

  16. Annual Technical Report, Materials Research Laboratory July 1, 1979 - June 30, 1980.

    Science.gov (United States)

    1980-06-30

    TeO2 in the glasses contributes to the formation of four-coordinated boron atoms. There is an apparent change in the coordination of tellurium atoms... Glasses , W. M. Risen, Jr., and Chemisorption and Related Surface Interactions, P. J. Estrup. Since many of the research areas are interrelated, cross...8 IInorganic Glasses .................................................................. 24 Introduction

  17. Hyperspectral Imaging and Obstacle Detection for Robotics Navigation

    Science.gov (United States)

    2005-09-01

    anatomy and diffraction process. 17 3.3 Technical Specifications of the System A. Brimrose AOTF Video Adaptor Specifications: Material TeO2 Active...sampled from glass case on person 2’s belt 530 pixels 20 pick-up white sampled from body panels of pick-up 600 pixels 21 pick-up blue sampled from

  18. Uudised : Preemia "edition 49" noodigraafikale. Noor muusik ئ Tallinn 2000. Bergenisse sõidab Bezrodnaja / Hugo Alter

    Index Scriptorium Estoniae

    Alter, Hugo-Eduard, 1929-2003

    2000-01-01

    Kirjastuse "Edition 49" noodigraafikaga teos võitis muusikakirjastuspreemia "Frankfurt 2000". 6.-9. juunini toimub rahvusvaheline konkurss "Noor muusik ئ Tallinn 2000", millest võtavad osa kuni 13 aastased muusikud 11-st riigist. "Klassika-Eurovisiooni" Eesti võistluse finaali võitis A.-L. Bezrodnaja, kes esindab Eestit võistluse Euroopa finaalis juunis Bergenis

  19. Bulletin of Materials Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Precursor sol for sol–gel silica layer was prepared from the starting material, tetraethylorthosilicate (TEOS). The sol was deposited onto borosilicate ... The physical thicknessand the refractive index of the layer were measured ellipsometrically (Rudolph Auto EL II) at 632.8 nm. About 10 × 10 mm surface area of the silica ...

  20. Balts show strong notes in Grammy Awards

    Index Scriptorium Estoniae

    2005-01-01

    Los Angeleses 8. veebr. Grammy Awards nominantide seas läti laulja Elina Garanca, dirigendid Paavo Järvi (Schumann "Cello Concerto" and Bloch's "Schelomo") ja Maris Jansons. Eelmisel aastal pälvis Grammy teos Sibelius "Cantatas" (esitajad Ellerheina tütarlastekoor Ester Loitme juhatusel, Eesti Rahvusmeeskoor, ERSO, dirigendid Ants Soots ja Paavo Järvi)

  1. Exploring E-Learning Acceptance among University Students in Thailand: A National Survey

    Science.gov (United States)

    Teo, Timothy; Ruangrit, Nammon; Khlaisang, Jintavee; Thammetar, Thapanee; Sunphakitjumnong, Kobkul

    2014-01-01

    This study surveys the e-learning acceptance of university students in Thailand. One thousand nine hundred and eighty-one (1,981) participants completed the E-Learning Acceptance Measure (Teo, 2010) which measures three constructs that predict e-learning acceptance (tutor quality, perceived usefulness, and facilitating conditions). Data analysis…

  2. Facile preparation of superhydrophobic surface with high adhesive ...

    Indian Academy of Sciences (India)

    in daily life (Yang et al 2007; Zhang et al 2011; Ogihara et al. 2012) ... models to explain the wetting phenomena on rough surfaces that leads to ... then tetraethylorthosilicate (TEOS) dissolved in isopropanol ... All scale bars are of 2 μm. ... rated by the air trapped in a closed 'liquid–solid' system ... This feature can be used in ...

  3. Self-assembly of the hydrogel polymer chain consisting of chitosan and chondroitin sulphate in the presence of theophylline

    International Nuclear Information System (INIS)

    Lopes, Lais C.; Piai, Juliana F.; Fajardo, Andre R.; Rubira, Adley F.; Muniz, Edvani C.

    2009-01-01

    In this work, polyelectronic complex (PEC) consisting of two polysaccharides were developed. One is chitosan (QT), cationic polymer, produced by the chitin deacetylation and the other is chondroitin sulphate (CS), anionic polymer, extracted from bovine or porcine aorta. The PECs were prepared in the presence of theophylline (TEO) for evaluating the influence of this drug in the polymer chains reorganization, as well as, studying the mechanical properties and release of SC and TEO in aqueous solutions on different pH conditions. By the obtained results, it was observed that the 84QT/15SC/TEO (% in weight) hydrogel is pH responsive because the CS releasing is more effective at pH 8, while the release of the TEO is higher at pH 2. The hydrogel showed mechanical properties more resistant to pH 2, 8 and 10 and this was attributed to interactions between the polymer chains. Finally, the X-rays profile showed the presence of peaks associated to reorganization of the chains in the hydrogel is at times larger than the hydrogel in the absence of solute. (author)

  4. Aasta tegu teadus- ja erialaraamatukogus / Ave Janu

    Index Scriptorium Estoniae

    Janu, Ave

    2010-01-01

    Teadusraamatukogu aasta teoks 2008 tunnistati RR-i virtuaalnäitus "Meie parlament ja aeg: fakte, sündmusi, dokumente, inimesi". Erialaraamatukogu aasta teo 2008 vääriliseks tunnistati nägemispuudega lugejatele heliteavikute automatiseeritud paljundamise ja posti teel laenutamise süsteem Eesti Pimedate Raamatukogus

  5. Propeller flaps for lower-limb trauma | Rogers | South African ...

    African Journals Online (AJOL)

    The propeller flap has become a versatile and important component in our reconstructive algorithm following complex lower limb trauma. First described by Hyakusoku in 1991, it has since been adapted and modified by Hallock and Teo. This article outlines our experience specifically with perforator pedicled propeller flaps ...

  6. Anticorrosives, encapsulates, catalytic supports and other novel ...

    Indian Academy of Sciences (India)

    protection to the metal surface. Thus, performance of ... or partially react with the hydrolysis products of the metal alkoxides in ... (TEOS) (Aldrich Chem., 97 %), CO2-free triple distilled water ... was done in a Nicolet 510 spectrometer, with an Ar laser by using ... MPR–AA matrix of our material, a strong interaction is observed ...

  7. Exploring the Digital Natives among Pre-Service Teachers in Turkey: A Cross-Cultural Validation of the Digital Native Assessment Scale

    Science.gov (United States)

    Teo, Timothy; Kabakçi Yurdakul, Isil; Ursavas, Ömer Faruk

    2016-01-01

    This study aims to explore the digital natives among a sample of pre-service teachers and in the process, examine the validity of a Turkish adaptation of the digital native assessment scale (DNAS) [Teo, T., & Fan, X. (2013). "Coefficient alpha and beyond: Issues and alternatives for educational research." "The Asia-Pacific…

  8. Eesti e-tiigri koha on hõivanud Läti ja Sloveenia / Henrik Roonemaa

    Index Scriptorium Estoniae

    Roonemaa, Henrik

    2004-01-01

    Tarkvarafirma Oracle asepresident Alfonso Di Ianni hindab Eesti e-arengut, tunnistades selle pidurdumist. Lisa: Postimees pakub välja Eesti eelmise aasta e-teo tiitlit väärivaid ettevõtmisi. Kommenteerivad: Andres Käärik, Andrus Aaslaid

  9. Itaalia piiskopid kurjustavad Cannes'i festivali filmi peale / Andres Laasik

    Index Scriptorium Estoniae

    Laasik, Andres, 1960-2016

    2002-01-01

    Festivali programmi valitud Marco Bellocchio "Usutund" ("L'ora di religione") on Itaalia katoliiklaste juhtide poolt hukka mõistetud kui usku teotav teos. 15. mail algava festivali avab komöödia "Lõpp Hollywoodiga" ("Hollywood Ending"). Ameerika režissöör David Lynch on valitud juhtima Cannesì filmifestivali žüriid

  10. Spectroscopic studies of Cu ions in sol–gel derived silica matrix

    Indian Academy of Sciences (India)

    Unknown

    Abstract. The Cu2+ ion doped silica gel matrices in monolithic shape were prepared by hydrolysis and condensation of tetraethyl orthosilicate (TEOS). The absorption, transmittance and fluorescence spectra of the gel matrices heat treated at different temperatures were monitored. The loss of water and hydroxyl group from.

  11. A dimorphic magnetorheological fluid with improved oxidation and chemical stability under oscillatory shear

    Czech Academy of Sciences Publication Activity Database

    Sedlačík, M.; Pavlínek, V.; Vyroubal, R.; Peer, Petra; Filip, Petr

    2013-01-01

    Roč. 22, č. 3 (2013) ISSN 0964-1726 R&D Projects: GA ČR GA202/09/1626 Grant - others:GA MŠk(CZ) ED2.1.00/03.0111 Institutional support: RVO:67985874 Keywords : goethites * magnetorheological fluids * MR fluids * tetraethylorthosilicate (TEOS) Subject RIV: BK - Fluid Dynamics Impact factor: 2.449, year: 2013

  12. Peamised vaidlusküsimused töölepingu lõpetamisel töötajapoolsel töölepingu tingimuste rikkumisel : [bakalaureusetöö] / Riina Rebane ; Tartu Ülikool, õigusteaduskond ; juhendaja: Inge-Maret Orgo

    Index Scriptorium Estoniae

    Rebane, Riina

    2003-01-01

    Üldised lähtekohad, töölepingu lõpetamine tulenevalt töös esinevatest olulistest puudustest, alkoholi tarvitamisest tingitud lõpetamine, omavoliline töölt puudumine, usalduse kaotamine, vääritu teo tõttu, protseduurireeglite järgimisega seotud probleemide tõttu

  13. Raputatud lapse sündroomi mõiste, olemus, tuvastamine ja ennetamine : [bakalaureusetöö] / Hettel Varik ; Tartu Ülikooli Õigusinstituut ; juhendaja: Endla Ülviste

    Index Scriptorium Estoniae

    Varik, Hettel

    2006-01-01

    Raputatud lapse sündroomi (RLS) mõiste, olemus ja probleemi teadvustamine, RLS-i põhjustanud tegevuse kui kuriteo tuvastamine, süüteo subjektiivse koosseisu sisustamine, kohtulahendid, RLS-i vältimise võimalikkusest, RLS-i tekitaja karistamine

  14. Preliminary biological screening of microbes isolated from cow dung ...

    African Journals Online (AJOL)

    Preliminary biological screening of microbes isolated from cow dung in Kampar. KC Teo, SM Teoh. Abstract. Five distinct morphologically and physiologically isolates were isolated from cow dung at Kampar, Perak, Malaysia and cultured on nutrient agar (NA) plates. Morphological studies including microscopic examination ...

  15. Karistusõiguse suund - ülekriminaliseerimine? / Timo Reinthal

    Index Scriptorium Estoniae

    Reinthal, Timo, 1981-

    2010-01-01

    Artikkel põhineb Riigikohtus valminud ülekriminaliseerimise analüüsil. Eesti süüteoõiguses esinevatest tendentsidest eesmärgiga anda hinnang karistusõiguse rollile õiguspärase käitumise tagamisel ning kohtupraktikale

  16. Thermochemical behaviour of Ru(II) complex–SiO2 microcomposites

    Indian Academy of Sciences (India)

    WINTEC

    both the gel spectra are to be expected accounting for the complex molar mass of ..... (ii) TEOS + OtEOS-produced gel: No principle diffe- rences in the DTG, DTA ... Acknowledgements. The study was carried out with the financial support from.

  17. Pro-lipogenic Action of Lysophosphatidic Acid in Ovarian Cancer

    Science.gov (United States)

    2014-04-01

    Function. IUBMB Life. 2008. 60: 347-354. 11. Tse C, Shoemaker AR, Adickes J, Anderson MG, Chen J, Jin S, Johnson EF, Marsh KC , Mitten MJ, Nimmer P...Ann. Oncol. 9, 437–442 14. Choi, J. W., Herr, D. R., Noguchi, K., Yung, Y. C., Lee, C. W., Mutoh, T., Lin, M. E., Teo , S. T., Park, K. E., Mosley, A

  18. Magnetic Resonance Imaging of Heart Failure Using a Swine Model

    Science.gov (United States)

    2011-03-21

    Suppl):I437-442. 36. McAlister FA, Teo KK, Taher M, Montague TJ, Humen D, Cheung L, Kiaii M, Yim R, Armstrong PW. Insights into the contemporary...Imaging 2001;13:714-721. 8. Ho VB, Meaney JF, Kent KC , Choyke PL, Watts R, Hood MN, Wang Y, Winchester P, Dong Q, Prince MR. Bolus-chase peripheral MR

  19. Cellular Consequences of Telomere Shortening in Histologically Normal Breast Tissues

    Science.gov (United States)

    2011-09-01

    axillary node metastasis, and histopathologic grading. Cancer 1984;54:2237–2242. 26 Anderson WF, Chu KC , Chatterjee N, et al. Tumor variants by hormone...alternatively lengthened telomeres. Am J Pathol 2010, 177:2694–2700 26. Hakin-Smith V, Jellinek DA, Levy D, Carroll T, Teo M, Timperley WR, McKay MJ

  20. Nrdp1-Mediated ErbB3 Increase During Androgen Ablation and Its Contribution to Androgen-Independence

    Science.gov (United States)

    2011-09-01

    GE, Pegram MD, Venkatesan N, Finn R, Yang G, Rahmeh M, Untch M, Rusnak DW, Spehar G, Mullin RJ, Keith BR, Gilmer TM, Berger M, Podratz KC , Slamon DJ...0) .............. co ....... co ....... p-Akt 0 0) -.: teo 0 0) ....... co 0 0) ....... co r ~ ....... T""+ ~ ....... -.:1’ + ~ ....... -.:1’ + z

  1. Rael Artel Gallery - kunst ja suhtluskeskkond / Siram

    Index Scriptorium Estoniae

    Siram, pseud., 1968-

    2005-01-01

    Rael Artel avas Pärnus Sütevaka Humanitaargümnaasiumi garaazhis galerii. Valgustite kujundus Andreas W, galerii sissepääsu juures inglise kunstniku Tim Bradeni reklaampannoo rekonstruktsioon "Diarama". Avanäituseks Jaan Evarti "Erinevad esitajad" ja Teo Spilleri neti.kunsti projekt

  2. Humanitaargümnaasiumi hoovil lubatakse kunsti sees vedelda / Silja Joon

    Index Scriptorium Estoniae

    Joon, Silja, 1966-

    2005-01-01

    Kunstiajaloolane Rael Artel avas Pärnus Sütevaka humanitaargümnaasiumi hoovis omanimelise suvegalerii, kus kahe kuu vältel näeb kaheksat näitust. Hooaeg avati kahe personaalnäitusega: graafilise disaineri Jaan Evarti väljapanekuga "Erinevad esitajad" ja sloveenia meediakunstniku Teo Spilleri kontseptsiooniaktsiooniga

  3. Framing Cultural Attributes for Human Representation in Military Training and Simulations

    Science.gov (United States)

    2008-09-01

    INTENTIONALLY LEFT BLANK xiii ACKNOWLEDGMENTS I would like to give a special thank you to my loving wife Tabitha and my wonderful three boys, Jalen, Teo and...How long have you been in the military? Thirteen years 3. What occupational community do you belong to in your branch of service? KC 130 pilot 4

  4. Military Review. Volume 87, Number 6, November-December 2007

    Science.gov (United States)

    2007-12-01

    Force Modernization and training,” China Brief: A Journal of News and Analysis, 6, no. 25 (19 December 2006). 25. eric teo , “asian Security and the...internal separatist movements.…The F/A-22 does not directly address these threats in any meaningful way, but the C-17 and KC -X (whatever the next

  5. Transplantation of Reprogrammed Autologous Stem Cells for Chronic Pain and Drug Abuse

    Science.gov (United States)

    2015-10-01

    after infusion. Cells Tissues Organs. 2001;169:12–20. 41. Karp JM, Leng Teo GS. Mesenchymal stem cell homing: the devil is in the details. Cell Stem...LL, and ZH isolated and characterized MSCs. ZH, LL, JS, KC , AL, JY, and LW performed the transplantation and behavioral experiments. LL and ZH

  6. Human Systems Integration Requirements

    Science.gov (United States)

    2009-09-01

    52 Stratofortress, C/ KC -135 Stratotanker, E-3 Sentry and contractor logistics support aircraft; as well as a substantial jet engine inventory...www.hqda.army.mil/ teo /Sutability%20Terms%20MOA%20Oct%2005.pdf q. ISO 9241-11, Ergonomic requirements for office work with visual display terminals (VDTs

  7. Bagatellid : maailm / Mailis Põld

    Index Scriptorium Estoniae

    Põld, Mailis

    2006-01-01

    Muusikasõnumeid mujalt maailmast: Pianist Irina Zahharenkova mainekal konkursil Itaalias taas võidukas. Lorin Maazel. Kadunud ja taasleitud Hindemithi teos jõudis esiettekandeni. Suri 20. sajandi olulisimaid ja isikupärasemaid heliloojaid György Ligeti

  8. R N P Choudhary

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science. R N P Choudhary. Articles written in Bulletin of Materials Science. Volume 23 Issue 4 August 2000 pp 239-241 Phase Transitions. Phase transitions in Na2TeO4 ceramics · N K Singh R N P Choudhary · More Details Abstract Fulltext PDF. Polycrystalline samples of NaTeO4 ...

  9. Ajalookirjanduse aastapreemia pälvis Aivar Jürgenson / Mart Kalm

    Index Scriptorium Estoniae

    Kalm, Mart, 1961-

    2012-01-01

    Ajalookirjanduse aastapreemiale kandideeris 15 teost. Žürii nägi preemiakandidaadina teaduslikku monograafiat, otsustades anda preemia elus autorile ja vältida juba preemiad saanud teoseid. Leiti, et statuuti tuleks täpsustada. Preemia pälvis Aivar Jürgensoni teos "Ladina rahva seas. Argentina ja sealsed eestlased"

  10. Nanoparticle-neural stem cells for targeted ovarian cancer treatment: optimization of silica nanoparticles for efficient drug loading

    Science.gov (United States)

    Patel, Z.; Berlin, J.; Abidi, W.

    2018-02-01

    One of the drugs used to treat ovarian cancer is cisplatin. However, cisplatin kills normal surrounding tissue in addition to cancer cells. To improve tumor targeting efficiency, our lab uses neural stem cells (NSCs), which migrate directly to ovarian tumors. If free cisplatin is loaded into NSCs for targeted drug delivery, it will kill the NSCs. To prevent the drug cisplatin from killing both the NSCs and normal surrounding tissue, our lab synthesizes silica nanoparticles (SiNPs) that act as a protective carrier. The big picture here is to maximize efficiency of tumor targeting using NSCs and minimize toxicity to these NSCs using SiNPs. The goal of this project is to optimize the stability of SiNPs, which is important for efficient drug loading. To do this, the concentration of tetraethyl orthosilicate (TEOS), one of the main components of SiNPs, was varied. We hypothesized that more TEOS equates to more stable SiNPs because TEOS contributes carbon to SiNPs, and thus a tightly-packed chemical structure results in a stable particle. Then, the stability of the SiNPs were checked in cell media and phosphate buffered saline (PBS). Lastly, the SiNPs were analyzed for their porosity using the transmission electron microscope (TEM). TEM imaging showed white spots in the 200-800 μL TEOS batches and no white spots in the 1000-1800 μL TEOS batches. The white spots were pores, which indicate instability. We concluded that the ultimate factor that determines the stability of SiNPs (100 nm) is the concentration of organic substance.

  11. Hydrogen-permeable TiO{sub 2}/SiO{sub 2} membranes formed by chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Heung Yong; Nam, Suk Woo; Yoon, Sung Pil [Korea Institute of Science and Technology, Seoul (Korea, Republic of)] [and others

    1994-12-31

    Thin films of TiO{sub 2}/SiO{sub 2} were deposited on the inner surface of the porous support tubes by the decomposition of tetraisopropyl titanate (TIPT) and tetraethyl orthosilicate (TEOS) at atmospheric pressure. Dense and hydrogen-permeable membranes were formed at 400-600{degrees}C. The permeation rate of H{sub 2} through the membrane at 600{degrees}C was about 0.3 cm{sup 3}(STP)/min-cm{sup 2}-atm and H{sub 2}/N{sub 2} permeation ratio was above 1000. The permeation properties of the membranes were investigated at various deposition temperatures and TIPT/TEOS concentrations. Decomposition of TIPT alone at temperatures above 400{degrees}C produced porous crystalline TiO{sub 2} films which were not H{sub 2}-selective. Decomposition of TEOS, however produced H{sub 2}-permeable SiO{sub 2} films at 400-600{degrees}C but film deposition rate was very low. Addition of TIPT to the TEOS stream significantly accelerated the deposition rate and produced highly H{sub 2}-selective films. Increasing the TEPT/TEOS ratios increased the deposition rate. The TiO{sub 2}/SiO{sub 2} membranes have the permeation properties comparable to those of SiO{sub 2} membranes. The TiO{sub 2}/SiO{sub 2} membranes were stable and did not show significant densification during the treatment at high temperature.

  12. Differential expression of AMPA-type glutamate receptor subunits during development of the chick optic tectum

    Directory of Open Access Journals (Sweden)

    Batista S.S.

    2002-01-01

    Full Text Available Glutamate receptors have been often associated with developmental processes. We used immunohistochemical techniques to evaluate the expression of the AMPA-type glutamate receptor (GluR subunits in the chick optic tectum (TeO. Chick embryos from the 5th through the 20th embryonic day (E5-E20 and one-day-old (P1 chicks were used. The three types of immunoreactivity evaluated (GluR1, GluR2/3, and GluR4 had different temporal and spatial expression patterns in the several layers of the TeO. The GluR1 subunit first appeared as moderate staining on E7 and then increased on E9. The mature GluR1 pattern included intense staining only in layer 5 of the TeO. The GluR2/3 subunits presented low expression on E5, which became intense on E7. The staining for GluR2/3 changed to very intense on E14 in tectal layer 13. Staining of layer 13 neurons is the most prominent feature of GluR immunoreactivity in the adult TeO. The GluR4 subunit generally presented the lowest expression starting on E7, which was similar to the adult pattern. Some instances of transient expression of GluR subunits were observed in specific cell populations from E9 through E20. These results demonstrate a differential expression of the GluR subunits in the embryonic TeO, adding information about their possible functions in the developmental processes of the visual system.

  13. An empirical investigation on the effects of spiritual leadership components on organizational learning capacity: A case study of Payame Noor University

    Directory of Open Access Journals (Sweden)

    Amir Hossein

    2013-06-01

    Full Text Available This paper presents an empirical investigation on the effects of spiritual leadership components on organizational learning capacity for a case study of Payame Noor University, Iran. The proposed study uses a standard questionnaire for measuring spirituality leadership proposed by Fry (2003 [Fry, L. W. (2003. Toward a theory of spiritual leadership. The leadership quarterly, 14(6, 693-727.] and for measuring the impact of organizational learning capacity, the proposed study uses another questionnaire proposed by Teo et al. (2006 [Teo, H. H., Wang, X., Wei, K. K., Sia, C. L., & Lee, M. K. (2006. Organizational learning capacity and attitude toward complex technological innovations: an empirical study. Journal of the American Society for Information Science and Technology, 57(2, 264-279.]. The results of our survey have indicated that all components of spiritual leadership, except love and altruism as meaningful, influence spirituality leadership, significantly.

  14. Response Surface Methodology for Design of Porous Hollow Sphere Thermal Insulator

    Science.gov (United States)

    Shohani, Nazanin; Pourmahdian, Saeed; Shirkavand Hadavand, Behzad

    2017-11-01

    In this study, response surface method is used for synthesizing polystyrene (PS) as sacrificial templates and optimizing the particle size. Three factors of initiator, stabilizer concentration and also stirring rate were selected as variable factors. Then, three different concentration of tetraethyl orthosilicate (TEOS) added to reaction media and core-shell structure with PS core and silica shell was developed. Finally, core-shell structure was changed to hollow silica sphere for using as thermal insulator. We observed that increased initiator concentration caused to larger PS particles, increase the stirring rate caused the smaller PS and also with increased the stabilizer concentration obtained that particle size decrease then after 2.5% began to increase. Also the optimum amount of TEOS was found.

  15. Contrast Gain Control Model Fits Masking Data

    Science.gov (United States)

    Watson, Andrew B.; Solomon, Joshua A.; Null, Cynthia H. (Technical Monitor)

    1994-01-01

    We studied the fit of a contrast gain control model to data of Foley (JOSA 1994), consisting of thresholds for a Gabor patch masked by gratings of various orientations, or by compounds of two orientations. Our general model includes models of Foley and Teo & Heeger (IEEE 1994). Our specific model used a bank of Gabor filters with octave bandwidths at 8 orientations. Excitatory and inhibitory nonlinearities were power functions with exponents of 2.4 and 2. Inhibitory pooling was broad in orientation, but narrow in spatial frequency and space. Minkowski pooling used an exponent of 4. All of the data for observer KMF were well fit by the model. We have developed a contrast gain control model that fits masking data. Unlike Foley's, our model accepts images as inputs. Unlike Teo & Heeger's, our model did not require multiple channels for different dynamic ranges.

  16. Composites in small and simple devices to increase mixing on detector surfaces

    Science.gov (United States)

    Hernandez, L. F.; Lima, R. R.; Leite, A. R.; Fachini, E. R.; Silva, M. L. P.

    2013-03-01

    This work aims at three different applications for the betterment of plasma generated-composite thin films: pre-mixing, spray formation in miniaturized structures and an increase in the performance of detector surfaces. Miniaturized structures were projected, simulated with FEMLAB® 3.2 software and then constructed. Clustered films made from tetraethoxysilane (TEOS) and nonafluoro(iso)butyl ether (HFE®) precursors were deposited on silicon, acrylic and quartz substrates for different kinds of film characterization/or in the projected structures. Physical and chemical characterization guided the selection of best films previous to/after UVC exposure. The active surfaces (plasma-deposited films) in structures were modified by UVC exposure and then tested. The applications include pre-mixing of liquids and/or spray formation, best results being obtained with surface covered by derivative-HFE films, which acted as passivation layers. Preliminary results show good humidity sensing for TEOS-derivative films.

  17. Rheological properties of poly(vinyl alcohol) (PVA) derived composite membranes for fuel cells

    International Nuclear Information System (INIS)

    Remiš, T

    2017-01-01

    Rheological properties of new anhydrous proton conducting membrane based on PVA, tetraethyl orthosilicate (TEOS),sulfosuccinic acid (SSA), titanium dioxide (TiO 2 )was examined at various stoichiometric ratios. SSA was used as sulfonating agents to form a crosslinked structure and as proton source, whereas TEO Sand TiO 2 were utilized to improve the thermal and mechanical properties of the membrane. In order to verify that all the substances were immobilized into the matrix, the membranes were analysed by means of FT-IR. The rheological, mechanical and thermal properties of the membranes were investigated using rheometer ARES G2 and thermogravimetic analyser (TGA).The analysis of mixed PVA solutions exhibited a unique behaviour of viscosity with increased crosslink density. The dynamic storage modulus G´ of dried composite membranes shows better mechanical resistance and increased tolerance to pressure applied during membrane electrode assembly (MEA). (paper)

  18. Rheological properties of poly(vinyl alcohol) (PVA) derived composite membranes for fuel cells

    Science.gov (United States)

    Remiš, T.

    2017-01-01

    Rheological properties of new anhydrous proton conducting membrane based on PVA, tetraethyl orthosilicate (TEOS),sulfosuccinic acid (SSA), titanium dioxide (TiO2)was examined at various stoichiometric ratios. SSA was used as sulfonating agents to form a crosslinked structure and as proton source, whereas TEO Sand TiO2were utilized to improve the thermal and mechanical properties of the membrane. In order to verify that all the substances were immobilized into the matrix, the membranes were analysed by means of FT-IR. The rheological, mechanical and thermal properties of the membranes were investigated using rheometer ARES G2 and thermogravimetic analyser (TGA).The analysis of mixed PVA solutions exhibited a unique behaviour of viscosity with increased crosslink density. The dynamic storage modulus G´ of dried composite membranes shows better mechanical resistance and increased tolerance to pressure applied during membrane electrode assembly (MEA).

  19. Large-scale synthesis of Tellurium nanostructures via galvanic displacement of metals

    Science.gov (United States)

    Kok, Kuan-Ying; Choo, Thye-Foo; Ubaidah Saidin, Nur; Rahman, Che Zuraini Che Ab

    2018-01-01

    Tellurium (Te) is an attractive semiconductor material for a wide range of applications in various functional devices including, radiation dosimeters, optical storage materials, thermoelectric or piezoelectric generators. In this work, large scale synthesis of tellurium (Te) nanostructures have been successfully carried out in different concentrations of aqueous solutions containing TeO2 and NaOH, by galvanic displacements of Zn and Al which served as the sacrificial materials. Galvanic displacement process is cost-effective and it requires no template or surfactant for the synthesis of nanostructures. By varying the concentrations of TeO2 and NaOH, etching temperatures and etching times, Te nanostructures of various forms of nanostructures were successfully obtained, ranging from one-dimensional needles and rod-like structures to more complex hierarchical structures. Microscopy examinations on the nanostructures obtained have shown that both the diameters and lengths of the Te nanostructures increased with increasing etching temperature and etching time.

  20. Robust modal curvature features for identifying multiple damage in beams

    Science.gov (United States)

    Ostachowicz, Wiesław; Xu, Wei; Bai, Runbo; Radzieński, Maciej; Cao, Maosen

    2014-03-01

    Curvature mode shape is an effective feature for damage detection in beams. However, it is susceptible to measurement noise, easily impairing its advantage of sensitivity to damage. To deal with this deficiency, this study formulates an improved curvature mode shape for multiple damage detection in beams based on integrating a wavelet transform (WT) and a Teager energy operator (TEO). The improved curvature mode shape, termed the WT - TEO curvature mode shape, has inherent capabilities of immunity to noise and sensitivity to damage. The proposed method is experimentally validated by identifying multiple cracks in cantilever steel beams with the mode shapes acquired using a scanning laser vibrometer. The results demonstrate that the improved curvature mode shape can identify multiple damage accurately and reliably, and it is fairly robust to measurement noise.

  1. Composites in small and simple devices to increase mixing on detector surfaces

    International Nuclear Information System (INIS)

    Hernandez, L F; Lima, R R; Leite, A R; Silva, M L P; Fachini, E R

    2013-01-01

    This work aims at three different applications for the betterment of plasma generated-composite thin films: pre-mixing, spray formation in miniaturized structures and an increase in the performance of detector surfaces. Miniaturized structures were projected, simulated with FEMLAB ® 3.2 software and then constructed. Clustered films made from tetraethoxysilane (TEOS) and nonafluoro(iso)butyl ether (HFE ® ) precursors were deposited on silicon, acrylic and quartz substrates for different kinds of film characterization/or in the projected structures. Physical and chemical characterization guided the selection of best films previous to/after UVC exposure. The active surfaces (plasma-deposited films) in structures were modified by UVC exposure and then tested. The applications include pre-mixing of liquids and/or spray formation, best results being obtained with surface covered by derivative-HFE films, which acted as passivation layers. Preliminary results show good humidity sensing for TEOS-derivative films.

  2. Spectroscopic studies of silver boro tellurite glasses

    Science.gov (United States)

    Kumar, E. Ramesh; Kumari, K. Rajani; Rao, B. Appa; Bhikshamaiah, G.

    2014-04-01

    The FTIR absorption and Raman scattering studies were used to obtain the structural information of AgI-Ag2O-[(1-x)B2O3-xTeO2] (x=0 to 1 mol% in steps of 0.2) glasses. The glassy nature of the compounds has been confirmed by X-ray diffraction. FTIR and Raman spectra were recorded for all samples at room temperature. FTIR spectra which provides the information about the change in bond structure of the glasses. Raman spectra provide the effect of TeO2 on SBT glass system is that as increasing the concentration of TeO2 the band intensity at 707 cm-1 increase.

  3. Preparation and characterization of boro-tellurite glasses

    Science.gov (United States)

    Kaur, Nirmal; Khanna, Atul; Krishna, P. S. R.

    2014-04-01

    Glass samples of the system: xB2O3-(100-x) TeO2; x= 15, 20, 25 and 30 mol% were prepared by melt quenching and characterized by X-ray diffraction, density measurements, Differential Scanning Calorimetry and FTIR spectroscopy. XRD confirmed the amorphous structure of all samples. Density of glasses decreased with increase in B2O3 concentration due to the replacement of heavier TeO2 with lighter B2O3 whereas the glass transition temperature increased from 339°C to 366°C; the later effect was due to increase in the concentration of stronger B-O bonds in the glass network. FTIR studies found that BO4 units convert into BO3 with the addition of B2O3.

  4. In vitro bioactivity and cytotoxicity of chemically treated glass fibers

    Directory of Open Access Journals (Sweden)

    Ângela Leão Andrade

    2004-12-01

    Full Text Available Samples of a commercial glass fiber FM® (Fiber Max were used to test the efficacy of a chemical sol-gel surface treatment to enhance their bioactivity. After treatment with tetraethoxysilane (TEOS, individual fiber samples were soaked into a simulated body fluid (SBF solution, from which they were removed at intervals of 5 and 10 days. Micrographs obtained by scanning electron microscopy (SEM analysis of samples chemically treated with TEOS revealed the formation of a hydroxyapatite (HA coating layer after 5 days into SBF solution. Fourier transform infrared spectroscopic (FTIR analyses confirmed that the coating layer has P-O vibration bands characteristic of HA. The in vitro cytotoxicity was evaluated using a direct contact test, minimum essential medium elution test (ISO 10993-5 and MTT assay. Fibers immersed in SBF and their extracts exhibited lower cytotoxicity than the controls not subjected to immersion, suggesting that SBF treatment improves the biocompatibility of the fiber.

  5. Fabrication and characterization of an all-solid tellurite-phosphate photonic bandgap fiber.

    Science.gov (United States)

    Cheng, Tonglei; Sakai, Yukiko; Suzuki, Takenobu; Ohishi, Yasutake

    2015-05-01

    We present an all-solid tellurite-phosphate photonic bandgap fiber (PBGF) with two layers of high-index rods (TeO2-Li2O-WO3-MoO3-Nb2O5, TLWMN) in the cladding (TeO2-ZnO-Li2O-K2O-Al2O3-P2O5, TZLKAP). TLWMN and TZLKAP glasses have good compatibility for fabricating the all-solid PBGF. Photonic bandgap (PBG) properties are calculated by the plane wave expansion method (PWM), and the results agree well with the measured transmission spectrum. Furthermore, the modal field patterns are measured at ∼1300 and 1520 nm, respectively. The light is confined to the core at ∼1300  nm and lost in the cladding at ∼1520  nm, which match well with the calculated modal field intensities.

  6. DSC and Raman studies of silver borotellurite glasses

    Science.gov (United States)

    Kaur, Amandeep; Khanna, Atul; Gonzàlez, Fernando

    2016-05-01

    Silver borotellurite glasses of composition: xAg2O-yB2O3-(100-x-y)TeO2 (x=20-mol%, y = 0, 10, 20 and 30-mol%) were prepared and characterized by density, X-ray diffraction (XRD), differential scanning calorimetry, and Raman spectroscopy. XRD confirmed the amorphous structure of all samples. Density of glasses decreases while the glass transition temperature increases with increase in B2O3 content from 10 to 30-mol%. Raman study shows that coordination number of Te with oxygen decreases steadily from 3.42 to 3.18 on adding B2O3 due to the transformation of TeO4 into TeO3 units.

  7. Investigations into the PbO-TeO2-B2O3 glass system

    International Nuclear Information System (INIS)

    Basariya, F.P.; Gugushvili, G.M.

    1975-01-01

    Based on the results of investigations of the system A-TeO 2 -B 2 O 3 and from the ternary phase diagram a region is determined of stable nonorganic glasses of the system PbO-TeO 2 -B 2 O 3 noncrystallizable at a temperature of 300 0 C and showing satisfactory chemical stability, as well as satisfactory isolation properties up to 300 0 C. On addition of an optimum amount of tellurium oxide one can obtain low-melting glasses with a temperature interval of 250-300 0 C. It is established that the substitution of PbO by TeO 2 or B 2 O 3 , or TeO 2 by B 2 O 3 leads to a decrease in the glass density. (author)

  8. Luminescent properties of Ln3+ doped tellurite glasses containing AlF3

    Science.gov (United States)

    Walas, Michalina; Pastwa, Agata; Lewandowski, Tomasz; Synak, Anna; Gryczyński, Ignacy; Sadowski, Wojciech; Kościelska, Barbara

    2016-09-01

    The low-phonon energy tellurite glasses TeO2-BaO-Bi2O3 and TeO2-BaO-Bi2O3-AlF3 triply doped with Eu3+, Tb3+, Tm3+ ions in two different molar ratios were synthesized using melt-quenching technique. Their structure and luminescence properties were widely investigated by X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR) and Photoluminescence Spectroscopy (PL). The luminescence spectra of Eu3+, Tb3+, Tm3+ co-doped glasses show apart of the bands corresponding to the 4f-4f transitions of lanthanide ions also band corresponding to glass matrix. AlF3 doping increases emission intensity, although to improve overall emission color further studies on molar composition of samples and the molar ratio of the components should be carried out.

  9. Synthesis and Characterization of Modified Epoxy Resins by Silicic Acid Tetraethyl Ester and Nano-SiO2

    Institute of Scientific and Technical Information of China (English)

    李海燕; 张之圣

    2004-01-01

    A kind of modified epoxy resins was obtained by condensation of epoxy resin with silicic acid tetraethyl ester(TEOS) and nano-SiO2. The reactions were performed with hydrochloric acid as a catalyst at 63 °C.The structure, thermal stability and morphological characteristics of the modified epoxy resins were studied through infrared spectra(FT-IR) analysis, thermogravimetric (TG) analysis and scanning electron microscopy respectively. It has been found from the IR and TG study that modified epoxy resins have greater thermal stability than epoxy resins, and its thermal stability has been improved by the formation of inter-crosslinked network structure. The modified epoxy resins exhibit heterogeneous morphology and heterogeneity increases with more TEOS feeding, which in turn confirms the formation of inter-crosslinked network structure in modified epoxy resins.

  10. Tellurite Composite Microstructured Optical Fibers with Tailored Chromatic Dispersion for Nonlinear Applications

    Science.gov (United States)

    Duan, Zhongchao; Liao, Meisong; Yan, Xin; Kito, Chihiro; Suzuki, Takenobu; Ohishi, Yasutake

    2011-07-01

    We report the fabrication of tellurite composite microstructured optical fibers (CMOFs) which consist of a TeO2-Li2O-WO3-MoO3-Nb2O5 (TLWMN) tellurite glass core and TeO2-ZnO-Na2O-La2O3 (TZNL) tellurite glass cladding. Flattened chromatic dispersion and tunable zero dispersion wavelength (ZDW) were realized in the small core diameter (˜1.5 µm) fiber with six surrounding air holes. The optical loss was measured to be about 4.0 dB/m in the spectral range of 1510-1640 nm. Supercontinuum (SC) generation was demonstrated by a femtosecond laser pumping at 1.55 µm. The threshold pump power for this novel tellurite CMOF was the lowest among tellurite microstructured optical fibers (MOFs).

  11. Computational Modelling of the Neural Representation of Object Shape in the Primate Ventral Visual System

    Directory of Open Access Journals (Sweden)

    Akihiro eEguchi

    2015-08-01

    Full Text Available Neurons in successive stages of the primate ventral visual pathway encode the spatial structure of visual objects. In this paper, we investigate through computer simulation how these cell firing properties may develop through unsupervised visually-guided learning. Individual neurons in the model are shown to exploit statistical regularity and temporal continuity of the visual inputs during training to learn firing properties that are similar to neurons in V4 and TEO. Neurons in V4 encode the conformation of boundary contour elements at a particular position within an object regardless of the location of the object on the retina, while neurons in TEO integrate information from multiple boundary contour elements. This representation goes beyond mere object recognition, in which neurons simply respond to the presence of a whole object, but provides an essential foundation from which the brain is subsequently able to recognise the whole object.

  12. ¿Se puede hablar de un arte queer español?

    Directory of Open Access Journals (Sweden)

    Juan Jesús Montiel Rozas

    2015-01-01

    Full Text Available Hasta la llegada de la década de los noventa la producción artística y teórica en España relativa a las cuestiones de género era prácticamente inexistente. No obstante, a partir de dicha década el feminismo comienza a desarrollarse y difundirse dentro de las fronteras nacionales a la par que la teoría queer da sus primeros pasos. En poco más de veinte años estos estudios han avanzado de un modo vertiginoso consiguiendo erigir, ya en el 2000, a algunos teóricos y artistas que son reconocidos a nivel internacional. En este artículo se re exiona sobre una de las consecuencias derivadas de la rapidez con que se ha producido el proceso: si tiene sentido hablar de un arte queer español.

  13. SiO2 coating of silver nanoparticles by photoinduced chemical vapor deposition

    International Nuclear Information System (INIS)

    Boies, Adam M; Girshick, Steven L; Roberts, Jeffrey T; Zhang Bin; Nakamura, Toshitaka; Mochizuki, Amane

    2009-01-01

    Gas-phase silver nanoparticles were coated with silicon dioxide (SiO 2 ) by photoinduced chemical vapor deposition (photo-CVD). Silver nanoparticles, produced by inert gas condensation, and a SiO 2 precursor, tetraethylorthosilicate (TEOS), were exposed to vacuum ultraviolet (VUV) radiation at atmospheric pressure and varying temperatures. The VUV photons dissociate the TEOS precursor, initiating a chemical reaction that forms SiO 2 coatings on the particle surfaces. Coating thicknesses were measured for a variety of operation parameters using tandem differential mobility analysis and transmission electron microscopy. The chemical composition of the particle coatings was analyzed using energy dispersive x-ray spectrometry and Fourier transform infrared spectroscopy. The highest purity films were produced at 300-400 0 C with low flow rates of additional oxygen. The photo-CVD coating technique was shown to effectively coat nanoparticles and limit core particle agglomeration at concentrations up to 10 7 particles cm -3 .

  14. FTIR and morphology of liquid epoxidized natural rubber acrylate (LENRA)/silica hybrid composites

    International Nuclear Information System (INIS)

    Eda Yuhana Ariffin; Azizan Ahmad; Dahlan Mohd; Mahathir Mohamed

    2009-01-01

    Synthesis of organic-inorganic hybrid composites was carried out by combination of liquid epoxidized natural rubber acrylate (LENRA) and silica. Silica was introduce to the matrix by sol gel technique. The sol-gel technique was employed to prepare silica using tetraethyorthosilicate (TEOS) as precursor. HDDA and irga cure 184 were added to the formulations as reactive diluents and photosensitizer, respectively. The chemical modification was studied by Fourier Transform Infrared (FTIR) and energy dispersive X-ray analysis (EDAX). The morphological studies were conducted by the optical and scanning electron microscopes (SEM). It shows that silica was dispersed very well in the matrix for lower concentration of TEOS while agglomeration occurs at the higher concentration. The average particles size of silica were less than 100 nm. (Author)

  15. Elinkaarikustannuslaskenta : Yttersundomin asuinalue

    OpenAIRE

    Laine, Katri

    2012-01-01

    Opinnäytetyön tarkoituksena on tutkia asuinalueiden kokonaiskustannusten pienentämistä kunnallisessa rakentamisessa. Työn tilaajana on Vaasan kaupungin Kuntatekniikka. Elinkaarikustannuslaskentaa ei ole aiemmin käytetty Vaasan kaupungin rakentamiskustannusten tarkastelussa. Tarkoituksena on selvittää, kannattaako elinkaarikustannuslaskenta kunnallisen rakentamisen kustannusten pienentämisessä ja kannattaako elinkaarikustannuslaskentaa hyödyntää muissa tulevissa hankkeissa. Tutkimuksen teo...

  16. Influence of crosslinker structure on performance of functionalised organic-inorganic hybrid sol-gel coating

    Science.gov (United States)

    Vasiljević, J.; Zorko, M.; Štular, D.; Tomšič, B.; Jerman, I.; Orel, B.; Medved, J.; Simončič, B.

    2017-10-01

    This research aimed to investigate the influence of the co-condensation of the three different organofunctional trialkoxysilane precursors with two different crosslinkers, i.e. tetraethoxysilane or organocyclotetrasiloxane on the performance and the washing fastness of this multicomponent multifunctional sol-gel coating on cellulose fibres. To this aim, a three-component equimolar sol mixture (MC), which included 1H,1H,2H,2H-perfluorooctyltriethoxysilane (SiF), 3-(trimethoxysilyl)-propyldimethyloctadecyl ammonium chloride (SiQ) and P,P-diphenyl-N-(3-(trimethoxysilyl)propyl) phosphinic amide (SiP) in combination with two different concentrations of TEOS (T and 3T) or organocyclotetrasiloxane 2,4,6,8-tetrakis(2-(diethoxy(methyl)silyl)ethyl)-2,4,6,8-tetramethyl-cyclotetrasiloxane (T4) as crosslinkers, was applied to the cotton fibres by a pad-dry-cure process. The functional properties of the coated samples before and after repeated washing were investigated by the water θ (W) and n-hexadecane θ (C16) static contact angle as well as water sliding (roll-off) (α) angle measurements. The inclusion of both TEOS and T4 into the MC sol increased the hydrophobic affect and simultaneously decreased the oleophobic effect of the MC coating. These phenomena were more pronounced for higher concentration of TEOS and T4 crosslinker. The inclusion of T4 into the MC sol improved the coating washing fastness to a significantly higher extent than the inclusion of TEOS, with respect to the applied concentrations.

  17. Tubin: The Parson of Reigi / Robert Layton

    Index Scriptorium Estoniae

    Layton, Robert

    1993-01-01

    Uuest heliplaadist "Tubin: The Parson of Reigi. Teo Maiste, Marika Eensalu, Ivo Kuusk, Annika Tõnuri, Urve Tauts, Leili Tammel, Tiit Tralla, Arvo Laid. Estonia Opera Company / Paul Mägi; Requiem for Fallen Soldiers. Urve Tauts, Talevaldis Deksnis, Urmas Leiten, Rein Tiido, Rein Roos. Estonian National Male Choir / Eri Klas. Ondine CD ODE 783-2 (2 discs: 116 min.). Recorded in association with the Estonian Cultural Foundation. Requiem - comparative version: Lund. Choral Soc., Järvi (9/88) CD 297

  18. Magnetic Turbulence in Clusters of Galaxies

    Science.gov (United States)

    2009-01-01

    plasmas que nos permiten confrontar conceptos teóricos del origen del campo magnético con observaciones detalladas. La turbulencia magnética en...por la turbulencia, entre el enfriamiento del gas y la actividad del chorro de la galaxia central. Finalmente se discuten métodos para medir ...ORGANIZATION NAME(S) AND ADDRESS( ES ) Max-Planck-Institute for Astrophysics,Karl-Schwarzschild Str.1,85741 Garching, Germany, , 8. PERFORMING ORGANIZATION

  19. Ohustatud homopingviinid / Udo Uibo

    Index Scriptorium Estoniae

    Uibo, Udo, 1956-

    2011-01-01

    Ameerika Raamatukoguühingu (American Library Association) sõnavabaduse osakond paneb igal aastal kokku nimekirja raamatutest, mille kohta on esitatud kõige rohkem kaebusi nõudega teose kättesaadavust sobimatu sisu tõttu piirata või teos raamatukogust üldse kõrvaldada. 2010 a. nimekirja juhib Peter Parnelli ja Justin Richardsoni lasteraamat "Tangoga kolmekesi" (And Tango Makes Three), kus lugejad panevad pahaks selle homoseksuaalsust, religioosseid vaateid ja sobimatust laste lugemisvaraks

  20. Enhanced thermal properties of novel shape-stabilized PEG composite phase change materials with radial mesoporous silica sphere for thermal energy storage

    OpenAIRE

    Min, Xin; Fang, Minghao; Huang, Zhaohui; Liu, Yan?gai; Huang, Yaoting; Wen, Ruilong; Qian, Tingting; Wu, Xiaowen

    2015-01-01

    Radial mesoporous silica (RMS) sphere was tailor-made for further applications in producing shape-stabilized composite phase change materials (ss-CPCMs) through a facile self-assembly process using CTAB as the main template and TEOS as SiO2 precursor. Novel ss-CPCMs composed of polyethylene glycol (PEG) and RMS were prepared through vacuum impregnating method. Various techniques were employed to characterize the structural and thermal properties of the ss-CPCMs. The DSC results indicated that...

  1. Fluorescence-based Sensing of 2,4,6-Trinitrotoluene (TNT) Using a Multi-channeled Poly(methyl methacrylate) (PMMA) Microimmunosensor

    Science.gov (United States)

    2010-01-22

    monoclonalframesethtm) for NRL. 3-Mercaptopropyltrimethoxysilane, tetraethylorthosilicate (TEOS) and dimethylsulfoxide ( DMSO ) were obtained from Sigma...prepared via hot-embossing and tri- solvent annealing (see Experimental section). Microchannels were coated with a sol-gel film using a previously...PMMA substrate that was tri- solvent bonded to a 1.0 mm thick PMMA coverslip. The footprint of the microfluidic device is 76 × 25 × 25 mm. The

  2. Micelle-template synthesis of hollow silica spheres for improving water vapor permeability of waterborne polyurethane membrane

    OpenAIRE

    Bao, Yan; Wang, Tong; Kang, Qiaoling; Shi, Chunhua; Ma, Jianzhong

    2017-01-01

    Hollow silica spheres (HSS) with special interior spaces, high specific surface area and excellent adsorption and permeability performance were synthesized via micelle-template method using cetyl trimethyl ammonium bromide (CTAB) micelles as soft template and tetraethoxysilane (TEOS) as silica precursor. SEM, TEM, FT-IR, XRD, DLS and BET-BJH were carried out to characterize the morphology and structure of as-obtained samples. The results demonstrated that the samples were amorphous with a hol...

  3. Parimaid õpetajaid näeb taas terve Eesti / Sirje Pärismaa

    Index Scriptorium Estoniae

    Pärismaa, Sirje, 1958-

    2014-01-01

    Üleriigilise üldhariduse tunnustussüsteemi „Eestimaa õpib ja tänab“ tänuüritusest, kus pälvisid auhinna aasta klassijuhataja Aare Veedla, Luua Metsanduskooli õpetaja Aino Mölder, Hugo Treffneri Gümnaasiumi õpetaja Aare Ristikivi, aasta lasteaiaõpetaja Julia Faizullova ning aasta teo tiitli pälvis Konguta kool

  4. Optical properties of lead–tellurite glasses doped with samarium ...

    Indian Academy of Sciences (India)

    Administrator

    392. Table 1. Density, molar volume, optical energy bandgap, refractive index, molar refraction and polarizability of oxide ion for. Sm2O3–PbO–TeO2 glasses. Glass composition (mol%). Energy. Molar. Polarizability. Density Molar volume bandgap. Refractive refraction. (αe). Sm2O3. PbO. TeO2. (ρ) (g/cm. 3. ) (Vm) (cm. –3. ).

  5. Pärdi Da Pacem ettekanne võitis Grammy auhinna

    Index Scriptorium Estoniae

    2007-01-01

    Arvo Pärdi teos "Da Pacem" Eesti Fi1harmoonia Kammerkoori ettekandes võitis 1. veebr. Los Angeleses 49. Grammy muusiakaauhindade jagamisel auhinna parima kooriettekande kategoorias. Parima klassikalise albumi heliproduktsiooni kategoorias läks auhind Michael Bishopile Briti helilooja Edward Elgari "Enigma: variatsioonid" ning Briti helilooja ja dirigendi Benjamin Britteni "Noore inimese teejuht orkestrini, neli mereteemalist interlüüdi" eest. Mõlema teose kandis ette Cincinnati sümfooniaorkester, mille dirigent on Paavo Järvi

  6. Mesoporous silica obtained with methyltriethoxysilane as co-precursor in alkaline medium

    Czech Academy of Sciences Publication Activity Database

    Putz, A.-M.; Wang, K.; Len, A.; Plocek, Jiří; Bezdička, Petr; Kopitsa, G. P.; Khamova, T. V.; Ianasi, C.; Sacarescu, L.; Mitróová, Z.; Savii, C.; Yan, M.; Almásy, L.

    2017-01-01

    Roč. 424, SI 3 (2017), s. 275-281 ISSN 0169-4332. [International Conference on Physics of Advanced Materials (ICPAM) /9./. Cluj Napoca, 08.09.2016-14.09.2016] Institutional support: RVO:61388980 Keywords : Sol-gel process * mtes/teos * Hydrophobic silica * mcm-41 Subject RIV: CA - Inorganic Chemistry OBOR OECD: Inorganic and nuclear chemistry Impact factor: 3.387, year: 2016

  7. Optical, physical and structural studies of boro-zinc tellurite glasses

    International Nuclear Information System (INIS)

    Gayathri Pavani, P.; Sadhana, K.; Chandra Mouli, V.

    2011-01-01

    To investigate the modification effect of the modifier ZnO on boro-tellurite glass, a series of glasses with compositions 50B 2 O 3 -(50-x)ZnO-xTeO 2 have been prepared by conventional melt quenching technique. Amorphous nature of the samples was confirmed through X-ray diffraction technique. Optical absorption and IR structural studies are carried out on the glass system. The optical absorption studies revealed that the cutoff wavelength increases while optical band gap (E opt ) and Urbach energy decreases with an increase of ZnO content. Refractive index evaluated from E opt was found to increase with an increase of ZnO content. The compositional dependence of different physical parameters such as density, molar volume, oxygen packing density, optical basicity, have been analyzed and discussed. The IR studies showed that the structure of glass consists of TeO 4 , TeO 3 /TeO 3+1 , BO 3 , BO 4 and ZnO 4 units. -- Research highlights: → Novel boro-zinc tellurite ternary glasses that can compete with boro-tellurite and zinc tellurite glasses are successfully prepared. → Boro-zinc tellurite ternary glasses are of higher refractive index compared with zinc tellurite glasses. → Optical, physical and structural properties of the novel ternary glass system are explained.→ At 30 mol% of ZnO, TeO 4 is replaced by ZnO 4 indicating the presence of ZnO 4 network.

  8. Targeting PRMT5 as a Novel Radiosensitization Approach for Primary and Recurrent Prostate Cancer Treatment

    Science.gov (United States)

    2016-10-01

    pressor programmed cell death 4, Cancer Res. 71 (2011) 5579–5587. [8] C. Nicholas , J. Yang, S.B. Peters, M.A. Bill, R.A. Baiocchi, F. Yan, S. Sif, S...Biochim. Biophys. Acta 1839 (2014) 1330–1340. [13] C.M. Koh, M. Bezzi, D.H. Low, W.X. Ang, S.X. Teo, F.P. Gay, M. Al-Haddawi, S.Y. Tan , M. Osato, A. Sabo

  9. Analysis Critical Thinking Stage of Eighth Grade in PBL-Scaffolding Setting To Solve Mathematical Problems

    OpenAIRE

    Nur Aisyah Isti; Arief Agoestanto; Ary Woro Kurniasih

    2017-01-01

    The purpose of this research was described critical thinking stage of students grade VIII in setting PBL and scaffolding to solve mathematics problems. Critical thinking stage consists of clarification, assesment, inference, and strategy/tactics. The subject were teo students in the level of capacity to think critical (uncritical, less critical, quite critical, and critical). So that this research subject was 8 students in VIII A One State Junior High School of Temanggung. The result showed a...

  10. Премию "Ясная Поляна" получил Фазиль Искандер

    Index Scriptorium Estoniae

    2011-01-01

    Kirjandusauhinna "Jasnaja Poljana" alajaotuses "Tänapäeva klassika" sai Fazil Iskander romaani "Сандро из Чегемы" eest. Nominatsioonis "XXI sajand" sai auhinna Jelena Katišonoki teos "Жили-были старик со старухой"

  11. Necesidades de formación psicopedagógica para la docencia universitaria

    OpenAIRE

    Sánchez Núñez, José Antonio

    2001-01-01

    El principal proposito del presente estudio de necesidades es detectar las careNcias mas especificas en la formacion psicopedagogica de los profesores universitarios que inician el ejercicio docente, con el fin de facilitar el diseño de un programa de formacion inicial que contribuya a la mejora de la calidad docente de la Universidad Politecnica de Madrid. El trabajo de investigacion se estructura en dos partes. Una primera parte, integrada por cuatro capitulos donde se encuadra el marco teo...

  12. Surface Enhanced Raman Scattering (SERS) Detection of Ammonium Nitrate (AN) Samples Fabricated Using Drop-on-Demand Inkjet Technology on Commercial and Fabricated SERS Substrates

    Science.gov (United States)

    2013-04-01

    a secondary ultraviolet ( UV )- visible (Vis) measurement. This method has been previously documented and typically has R 2 values above 0.998 and...surface, respectively. These concentrations were independently validated by UV -Vis measurements (data not shown), and have been previously discussed (83...laser-induced Breakdown Spectroscopy. J. Anal. Atom. Spectro . 2011, 26 (7), 1445–1450. 30. Banas, A.; Banas, K.; Breese, M.B.H.; Loke, J.; Teo, B. H

  13. Karistusõiguslik hädakaitse ja hädaseisund põhiõiguste piiramise alusena koolides ning nende suhestumine 1. jaanuaril 2016 jõustuva lastekaitseseaduse § 24 lõikega 3 / Anneli Soo

    Index Scriptorium Estoniae

    Soo, Anneli, 1984-

    2015-01-01

    Analüüs 1. jaanuaril 2016 jõustuva LaKS § 24 lõike 3 tähendusest teo õigusvastasust välistava asjaoluna ning kas see harmoneerub karistusõiguse dogmaatikaga hädakaitse ja hädaseisundi valdkonnas. Füüsilise vägivalla kasutamisest hädakaitse ja hädaseisundi olukorras koolis, vastavast kohtupraktikast

  14. Study of the pluronic-silica interaction in synthesis of mesoporous silica under mild acidic conditions.

    Science.gov (United States)

    Sundblom, Andreas; Palmqvist, Anders E C; Holmberg, Krister

    2010-02-02

    The interaction between silica and poly(ethylene oxide) (PEO) in water may appear trivial and it is generally stated that hydrogen bonding is responsible for the attraction. However, a literature search shows that there is not a consensus with respect to the mechanism behind the attractive interaction. Several papers claim that only hydrogen bonding is not sufficient to explain the binding. The silica-PEO interaction is interesting from an academic perspective and it is also exploited in the preparation of mesoporous silica, a material of considerable current interest. This study concerns the very early stage of synthesis of mesoporous silica under mild acidic conditions, pH 2-5, and the aim is to shed light on the interaction between silica and the PEO-containing structure directing agent. The synthesis comprises two steps. An organic silica source, tetraethylorthosilicate (TEOS), is first hydrolyzed and Pluronic P123, a poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) block copolymer, is subsequently added at different time periods following the hydrolysis of TEOS. It is shown that the interaction between the silica and the Pluronic is dependent both on the temperature and on the time between onset of TEOS hydrolysis and addition of the copolymer. The results show that the interaction is mainly driven by entropy. The effect of the synthesis temperature and of the time between hydrolysis and addition of the copolymer on the final material is also studied. The material with the highest degree of mesoorder was obtained when the reaction was performed at 20 degrees C and the copolymer was added 40 h after the start of TEOS hydrolysis. It is claimed that the reason for the good ordering of the silica is that whereas particle formation under these conditions is fast, the rate of silica condensation is relatively low.

  15. Processing and characterization of new oxy-sulfo-telluride glasses in the Ge-Sb-Te-S-O system

    International Nuclear Information System (INIS)

    Smith, C.; Jackson, J.; Petit, L.; Rivero-Baleine, C.; Richardson, K.

    2010-01-01

    New oxy-sulfo-telluride glasses have been prepared in the Ge-Sb-Te-S-O system employing a two-step melting process which involves the processing of a chalcogenide glass (ChG) and subsequent melting with TeO 2 or Sb 2 O 3 . The progressive incorporation of O at the expense of S was found to increase the density and the glass transition temperature and to decrease the molar volume of the investigated oxy-sulfo-telluride glasses. We also observed a shift of the vis-NIR cut-off wavelength to longer wavelength probably due to changes in Sb coordination within the glass matrix and overall matrix polarizability. Using Raman spectroscopy, correlations have been shown between the formation of Ge- and Sb-based oxysulfide structural units and the S/O ratio. Lastly, two glasses with similar composition (Ge 20 Sb 6 S 64 Te 3 O 7 ) processed by melting the Ge 23 Sb 7 S 70 glass with TeO 2 or the Ge 23 Sb 2 S 72 Te 4 glass with Sb 2 O 3 were found to have slightly different physical, thermal, optical and structural properties. These changes are thought to result mainly from the higher moisture content and sensitivity of the TeO 2 starting materials as compared to that of the Sb 2 O 3 . - Graphical abstract: In this paper, we discuss our most recent findings on the processing and characterization of new ChG glasses prepared with small levels of Te, melted either with TeO 2 or Sb 2 O 3 powders. We explain how these new oxy-sulfo-telluride glasses are prepared and we correlate the physical, thermal and optical properties of the investigated glasses to the structure changes induced by the addition of oxygen in the Ge-Sb-S-Te glass network.

  16. Platform for High-Assurance Cloud Computing

    Science.gov (United States)

    2016-06-01

    821715). Santa Clara, CA. February 2015. 36. Zhiyuan Teo, Vera Kutsenko, Ken Birman, and Robbert van Renesse. IronStack: performance, stability and...1988. 51. Douglas E . Comer and David L. Stevens. Internetworking with TCP/IP, Vol. III: Client- Server Programming and Applications, Linux/Posix...pp635-671, February 2012. E +16 Ittay Eyal, Adam Efe Gencer, Emin Gun Sirer, and Robbert van Renesse. Bitcoin-NG: A Scalable Blockchain Protocol

  17. Short-range structure of barium tellurite glasses and its correlation with stress-optic response

    Science.gov (United States)

    Kaur, Amarjot; Khanna, Atul; Fábián, Margit

    2018-06-01

    The atomic parameters of metal ion-oxygen speciation such as bond-lengths and nearest neighbor distances for Ba-O, Te-O and O-O pairs, co-ordination numbers and bond angle distributions for O-Ba-O, O-Te-O and O-O-O linkages are determined by neutron diffraction and Reverse Monte Carlo simulations on the series of xBaO-(100-x)TeO2 glasses containing 10, 15 and 20 mol% BaO. The glass network depolymerizes and the average Te-O co-ordination number decreases from 3.60 ± 0.02 to 3.48 ± 0.02 with increase in BaO concentration. Te-O bond lengths are in the range: 1.97 ± 0.01–1.92 ± 0.01 Å. Ba2+ is mostly in octahedral coordination and the Ba-O bond lengths are in the range: 2.73 ± 0.01 to 2.76 ± 0.03 Å. Te-O co-ordination number is also determined by Raman spectroscopy and it shows good agreement with the neutron data. The short-range structural properties i.e. metal ion coordination number (Nc) and bond lengths (d) were correlated with the stress-optic response. The bonding characteristic, Br values were determined from the structural data of xBaO-(100-x)TeO2 glasses and were used to predict the stress-induced birefringence properties.

  18. Experimental and Computational Characterization of Combustion Phenomena

    Science.gov (United States)

    2006-05-01

    combustors without installing glass , quartz, or sapphire windows when using terahertz radiation. To explore the potential diagnostics utility of T...laser was reduced using a Spectra-Physics Model 3980 pulse selector. This device employs a TeO2 acousto-optic modulator to select subsets of pulses...equipped with a UG-11 and two WG-295 colored glass filters to reduce visible and laser-scattered light, respectively. OH-PLIF images were acquired

  19. High-Purity Glasses Based on Arsenic Chalcogenides

    Science.gov (United States)

    2001-06-01

    Chemical interaction of chalcogenides and some impurities (CS 2, TeO2 ) with the quartz glass at high temperature leads to the thin layers formation...UNCLASSIFIED Defense Technical Information Center Compilation Part Notice ADPO1 1523 TITLE: High-Purity Glasses Based on Arsenic Chalcogenides...Materials Vol. 3, No. 2, June 2001, p. 341 - 349 HIGH-PURITY GLASSES BASED ON ARSENIC CHALCOGENIDES M. F. Churbanov, I. V. Scripachev, G. E. Snopatin, V. S

  20. Structure of the Global Nanoscience and Nanotechnology Research Literature

    Science.gov (United States)

    2006-01-01

    glasses obtained from fine silica powder modified with galvanic waste addition In situ high-temperature X-ray study of ZnO- TeO2 glass ...spectroscopic studies of rare earth ions (Er3+, Yb3+, and Tm3+), especially in doped crystals and glass ceramics (82 Records) Cluster 27 (Countries...sintering, including liquid phase (dominant); ceramics-ZrO2, YSZ, Al2O3, SiC (dominant); ceramic dielectric properties; glass ceramics; nanorod