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Sample records for chromiumiii-activated yttrium aluminum

  1. Synthesis of aluminum-based scandium-yttrium master alloys

    Science.gov (United States)

    Bazhin, V. Yu.; Kosov, Ya. I.; Lobacheva, O. L.; Dzhevaga, N. V.

    2015-07-01

    The preparation technology for an Al-2% Sc-0.5% Y master alloy using aluminum-manganese alloys has been developed and tested. The microstructure of the prepared master alloy is studied and the compositions of intermetallics is determined. The efficient technological parameters of the synthesis are determined. It is shown that varying the compositions of starting reagents and alloying additions and optimizing the process conditions (temperature, mixing, etc.) allow us to forecast the manufacturing and operating characteristics of aluminum-based master alloys. Joint additions of scandium and yttrium oxides to a charge favor a substantial decrease in the grain size of the formed intermetallics; this effect appears to the utmost in the case of microallying with yttrium up to 0.5 wt %.

  2. Upconversion luminescence in Yb 3+-doped yttrium aluminum garnets

    Science.gov (United States)

    Xu, Xiaodong; Zhao, Zhiwei; Song, Pingxin; Jiang, Benxue; Zhou, Guoqing; Xu, Jun; Deng, Peizhen; Bourdet, Gilbert; Christophe Chanteloup, Jean; Zou, Ji-Ping; Fulop, Annabelle

    2005-03-01

    In this paper, we present results on upconversion luminescence performed on Yb 3+-doped yttrium aluminum garnets under 940 nm excitation. The upconversion luminescence was ascribed to Yb 3+ cooperative luminescence and the presence of rare earth impurity ions. The cooperative luminescence spectra as a function of Yb concentration were measured and the emission intensity variation with Yb concentration was discussed. Yb 3+ energy migration quenched the cooperative luminescence of Yb:YAG crystals with doping level over 15 at%.

  3. KINETICS OF GRAIN-GROWTH OF YTTRIUM ALUMINUM GARNET FIBERS PREPARED BY SOL-GEL METHOD

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    Tan H.

    2013-12-01

    Full Text Available The yttrium aluminum garnet (YAG long fibers were prepared by the sol-gel method using aluminum chloride, aluminum powder, yttrium oxide and acetic acid as raw materials. The grain growth law is given by Dn – D0n = Kt (D0 = initial grain size, D = average grain size at time t, n = grain growth exponent and K = reaction constant. The grain growth exponent and activation energy of YAG fibers are ≈ 3 and 200 kJ/mol, respectively. The grain-growth behaviors of YAG were influenced by experimental conditions such as raw materials, initial particle size, initial particle distribution, etc.

  4. Optical bistability in erbium-doped yttrium aluminum garnet crystal combined with a laser diode.

    Science.gov (United States)

    Maeda, Y

    1994-01-10

    Optical bistability was observed in a simple structure of an injection laser diode combined with an erbium-doped yttrium aluminum garnet crystal. Since a hysteresis characteristic exists in the relationship between the wavelength and the injection current of a laser diode, an optical memory function capable of holding the output status is confirmed. In addition, an optical signal inversion was caused by the decrease of transmission of the erbium-doped yttrium aluminum garnet crystal against the red shift (principally mode hopping) of the laser diode. It is suggested that the switching time of this phenomenon is the time necessary for a mode hopping by current injection.

  5. Nanostructured yttrium aluminum garnet powders synthesized by co-precipitation method using tetraethylenepentamine

    Institute of Scientific and Technical Information of China (English)

    李先学; 王文菊

    2009-01-01

    Tetraethylenepentamine(C8H23N5,TEPA) has been used as a novel precipitant to synthesize yttrium aluminum garnet(Y3Al5O12,YAG) precursor from a mixed solution of aluminum and yttrium nitrates via a normal-strike co-precipitation method without controlling the pH value during precipitation process.The original precursor was analyzed by thermogravimetry/differential scanning calorimetry(TG/DSC).The evolution of phase composition and micro-structure of the as-synthesized YAG powders were characterized by X-ray ...

  6. Effects of yttrium, aluminum and chromium concentrations in bond coatings on the performance of zirconia-yttria thermal barriers

    Science.gov (United States)

    Stecura, S.

    1980-01-01

    A cyclic furnace study was conducted on thermal barrier systems to evaluate the effects of yttrium, chromium and aluminum in nickel-base alloy bond coatings and the effect of bond coating thickness on yttria-stabilized zirconia thermal barrier coating life. Without yttrium in the bond coatings, the zirconia coatings failed very rapidly. Increasing chromium and aluminum in the Ni-Cr-Al-Y bond coatings increased total coating life. This effect was not as great as that due to yttrium. Increased bond coat thickness was also found to increase life.

  7. High-spin europium and gadolinium centers in yttrium-aluminum garnet

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    Vazhenin, V. A.; Potapov, A. P.; Asatryan, G. R.; Uspenskaya, Yu. A.; Petrosyan, A. G.; Fokin, A. V.

    2016-08-01

    Electron-spin resonance spectra of Eu2+ and Gd3+ centers substituting Y3+ ions in single-crystal yttrium-aluminum garnet have been studied and the parameters of their rhombic spin Hamiltonian have been determined. The fine-structure parameters of the above ions have been calculated in the superposition model disregarding changes in the angular coordinates of the ligand environment of the impurity defect thus demonstrating the necessity of taking these changes into account.

  8. Synthesis and characterization of yttrium-aluminum-iron and yttrium-cerium-iron citric complexes

    Institute of Scientific and Technical Information of China (English)

    N. Petrova; D. Todorovsky; I. Mitov; Tyuliev

    2008-01-01

    Fe-, Y-Fe-Al- and Y-Ce-Fe- citrates were synthesized in ethylene glycol (EG) medium under conditions similar to those used in the polymerized complex method. Their elemental composition, IR, 13C and 1H NMR, X-ray photoelectron and Mossbauer spectra were studied, and formulae describing their composition were proposed. The complexes contained EG bonded as adduct and ester with citric acid ligand and did not contain ligands with deprotonated alcoholic groups. The complexes consisted of agglomerated spheres, 0.7-3μm in diameter. The local composition of the products was established by energy dispersive X-ray microanalysis. The comparison of the number of the ligands, their average electrical charge and the esterification degree of mono-, di- and trimetallic complexes proved the mixed-metal nature of the species studied. The thermal decomposition of the complexes was studied and a general scheme of the processes taking place was proposed. Highly crystalline, phase homogeneous Y3Fe4AlO12 was produced after heating the respective complex at 1000℃. Ce-doped yttrium-iron garnet, similarly prepared, contained traces of CeO2.

  9. Preparation of neodymium-doped yttrium aluminum garnet powders and fibers

    Institute of Scientific and Technical Information of China (English)

    R.López; J.Zárate; E.A.Aguilar; J.Mu(n)oz-Salda(n)a

    2008-01-01

    Using nitrate precursors, a novel spray-drying assisted citrate gel process for the preparation of neodymium-doped yttrium alumi-num garnet (YAG) phase was developed. Synthesis of single-phase polycrystalline YAG was achieved at temperatures as low as 800 ℃ us-ing the spray-drying methodology whilst conventional approaches currently available require 1000 ℃. Initially, a solution was prepared by mixing aluminum and yttrium nitrates, citric acid, etilenglycol and neodymium oxide. This solution was dried by pulverization (spray dryer) to obtain aggregated precursor powders of the compound. These aggregates were calcined at 800, 850 and 900 ℃ to determine the phase evolution from amorphous to crystalline by X-ray diffraction (XRD). The morphology of aggregates was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Moreover, through XRD it was determined that the crystallization of YAG phase started at about 800 ℃ without any intermediate phases. The powders were composed of spherical aggregates with an average diame-ter of 1 μm. From these powders, ceramic fibers with additions of 2at.% and 5at.% Nd, were extracted from the melt with diameters ranging from 30 μm to 50 μm.

  10. Two-photon-absorption cross section of Nd3+ in yttrium aluminum garnet and yttrium lithium fluoride near 1.06 μm

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    Chase, L. L.; Payne, Stephen A.

    1986-12-01

    We have measured the spectrally integrated two-photon-absorption (TPA) cross sections for the 4I9/2--> 4G7/2 transitions of Nd3+ and obtained values of 1.2×10-40 and 0.15×10-40 cm4 for Nd3+-doped yttrium aluminum garnet (YAG) and yttrium lithium fluoride (YLF), respectively. These results are in satisfactory agreement with theoretical calculations based on the properties of Nd3+ free-ion wave functions. The difference between YAG and YLF, however, is not accounted for by the free-ion theory and suggests that the intermediate-state energies and wave functions are considerably host dependent. In addition, we conclude, based on our measurements, that rare-earth TPA will not contribute significantly to either losses or the nonlinear refractive index in typical laser media employing rare-earth ions.

  11. Study on phosphating treatment of aluminum alloy: role of yttrium oxide

    Institute of Scientific and Technical Information of China (English)

    ZHANG Shenglin

    2009-01-01

    Zinc phosphate coatings formed on 6061-Al alloy, after dipping in phosphating solutions containing different amounts of Y2O3(yttrium oxide), were studied by scanning electron microscopy (SEM), X-ray diffraction (XRD) and electrochemical measurements. Significant variations in the morphology and corrosion resistance afforded by zinc phosphate coating were especially observed as Y2O3 in phosphating solution varied from 0 to 40 mg/L. The addition of Y2O3 changed the initial potential of the interface between aluminum alloy substrate and phosphating solution and increased the number of nucleation sites. The phosphate coating thereby was less porous structure and covered the surface of aluminum alloy completely within short phosphating time. Phosphate coating was mainly composed of Zn3(PO4)2-4H2O (hopeite) and AIPO4(aluminum phosphate). Y2O3, as an additive of phosphatization, accelerated precipitation and refined the gain size of phosphate coating. The corrosion resistance of zinc phosphate coating in 3% NaCl solution was improved as shown by po-larization measurement. In the present research, the optimal amount of Y2O3 was 10-20 mg/L, and the optimal phosphating time was 600 s.

  12. Luminescent down shifting effect of Ce-doped yttrium aluminum garnet thin films on solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Shao, Guojian; Lou, Chaogang; Kang, Jian; Zhang, Hao [School of Electronic Science and Engineering, Southeast University, Nanjing 210096, Jiangsu Province (China)

    2015-12-21

    Ce-doped yttrium aluminum garnet (YAG:Ce) thin films as luminescent down shifting (LDS) materials are introduced into the module of crystalline silicon solar cells. The films are deposited by RF magnetron sputtering on the lower surface of the quartz glass. They convert ultraviolet and blue light into yellow light. Experiments show that the introduction of YAG:Ce films improves the conversion efficiency from 18.45% of the cells to 19.27% of the module. The increasing efficiency is attributed to LDS effect of YAG:Ce films and the reduced reflection of short wavelength photons. Two intentionally selected samples with similar reflectivities are used to evaluate roughly the effect of LDS alone on the solar cells, which leads to a relative increase by 2.68% in the conversion efficiency.

  13. Sol-gel Synthesis and Characterisation of NanocrystallineYttrium Aluminum Garnet Nanopowder

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    Kiranmala Devi

    2008-07-01

    Full Text Available The synthesis of  yttrium aluminum garnet (YAG (Y3 Al5O12 nanopowder was carried outby sol-gel method. Y(NO33.6H2O, Al(NO33.9H2O in the presence of citric acid as complexing agent were used as starting materials. YAG nanopowder was characterised by FTIR, TGA, andXRD. To get phase-pure nanocrystalline YAG powder at relatively lower temperature, calcinationat various temperatures was studied and calcination temperature was optimised. Particle size,estimated by XRD using Scherrer's equation, was found to be 28Œ35 nm which was further confirmed by transmission electron microscopy. The particle morphology was studied by SEM.Defence Science Journal, 2008, 58(4, pp.545-549, DOI:http://dx.doi.org/10.14429/dsj.58.1675

  14. Composite filling removal with erbium:yttrium-aluminum-garnet laser: morphological analyses.

    Science.gov (United States)

    Correa-Afonso, Alessandra M; Palma-Dibb, Regina G; Pécora, Jesus Djalma

    2010-01-01

    Considering the increase in esthetic restorative materials and need for improvement in unsatisfactory restoration substitution with minimal inadvertent removal of healthy tissues, this study assessed the efficacy of erbium:yttrium-aluminum-garnet (Er:YAG) laser for composite resin removal and the influence of pulse repetition rate on the morphological analyses of the cavity by scanning electron microscope. Composite resin fillings were placed in cavities (1.0 mm deep) prepared in bovine teeth, and the 75 specimens were randomly assigned to five groups according to the technique used for composite filling removal (high-speed diamond bur, group I, as a control, and Er:YAG laser, 250 mJ output energy and 80 J/cm(2) energy density, using different pulse repetition rates: group II, 2 Hz; group III, 4 Hz; group IV, 6 Hz; group V, 10 Hz). After the removal, the specimens were split in the middle, and we analyzed the surrounding and deep walls to check for the presence of restorative material. The estimation was qualitative. The surfaces were examined with a scanning electron microscope. The results revealed that the experimental groups presented bigger amounts of remaining restorative material. The scanning electron microscopy (SEM) analyses showed irregularities of the resultant cavities of the experimental groups that increased proportionally with increase in repetition rate.

  15. Preparation of Neodymium-Doped Yttrium Aluminum Garnet Transparent Ceramics by Homogeneous Precipitation Method

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Neodymium doped-yttrium aluminum garnet (Nd: YAG) transparent polycrystalline ceramics already become substitutes of single crystals because they are provided with easy fabrication, low cost, large size, highly doped concentration, high heat conductivity, mass fabrication, multi-layers and multi-functions. The Nd: YAG precursor powders with loosely dispersed, slightly agglomerated, super fine and YAG cubic crystal phase were synthesized at 1100 ℃ by the hocal stabilizer, TEOS as sintering additive. The Nd:YAG transparent ceramics were prepared after being vacuum sintered at 1700 ℃ for 5 h. The Nd:YAG ceramic materials were characterized by the TG-DTA, XRD, FT-IR, TEM, FEG-ESEM and FT-PL. The results show that the crystallization temperature of YAG is 850 ℃ and the intermediate crystal phase YAP forming during the heat treatment transforms to YAG cubic crystal phase at 1050 ℃. The lasing wavelength of (Nd0.01Y0.99)3Al5O12 transparent ceramics is 1.065 μm and there exists a slight red-shift compared to the single crystal with the same chemical composition. The optical transmittance is 45% in the visible light and 58% in the near infrared light and the optical transmittance descends with the decreasing the wavelength.

  16. The use of holmium-yttrium aluminum garnet laser as pit and fissure cleaner

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    Armasastra Bahar

    2009-09-01

    Full Text Available Background: The prevention and management of pit and fissure caries has become relatively more important in recent times. There is a need for an effective preventive measure against pit and fissure caries. Purpose: The purpose of this study was to investigate the effect of laser beam as a cleaning method of pits and fissures. Methods: Ho-YAG laser which has a wavelength of 2.1 µm was used in this experiment. The specimens were extracted human teeth. The effect of three cleaning methods was examined comparatively by scoring the cleaned area of fissure, namely laser irradiation with Ho-YAG laser, chemico-mechanical with combination of 10% NaOCl and ultrasonic scaler and mechanical with ultrasonic scaler. Vertico-bucco-lingual serial ground sections of each tooth were observed under light microscopy. Scoring the depth of cleaned area was performed by comparing the depth of fissure. result: Progressive result was obtained on the cleaning effect of three methods laser irradiation methods which was the most effective compared to other methods but statistically was not significant. Cleaned area of laser irradiation method was 48.91%, chemico-mechanical method was 41.77% and mechanical method was 36.78%. Conclusion: Holmium -yttrium aluminum garner laser is a relatively new method for pit and fissure cleaning even though the effectivity is not yet maximal. More research is needed to maximize the use of this laser.

  17. Effect of erbium:yttrium-aluminum-garnet laser energies on superficial and deep dentin microhardness.

    Science.gov (United States)

    Chinelatti, Michelle Alexandra; Raucci-Neto, Walter; Corona, Silmara Aparecida Milori; Palma-Dibb, Regina Guenka

    2010-05-01

    This study evaluated the microhardness of superficial and deep dentin irradiated with different erbium:yttrium-aluminum-garnet (Er:YAG) laser energies. Seventy-two molars were bisected and randomly assigned to two groups (superficial dentin or deep dentin) and into six subgroups (160 mJ, 200 mJ, 260 mJ, 300 mJ, 360 mJ, and control). After irradiation, the cavities were longitudinally bisected. Microhardness was measured at six points (20 microm, 40 microm, 60 microm, 80 microm, 100 microm, and 200 microm) under the cavity floor. Data were submitted to analysis of variance (ANOVA) and Fisher's tests (alpha = 0.05). Superficial dentin presented higher microhardness than deep dentin; energy of 160 mJ resulted in the highest microhardness and 360 mJ the lowest one. Values at all points were different, exhibiting increasing microhardness throughout; superficial dentin microhardness was the highest at 20 microm with 160 mJ energy; for deep dentin, microhardness after irradiation at 160 mJ and 200 mJ was similar to that of the control. The lowest energy increased superficial dentin microhardness at the closest extent under the cavity; deep dentin microhardness was not altered by energies of 160 mJ and 200 mJ.

  18. Neodymium:Yttrium aluminum garnet laser in the management of oral leukoplakia: A case series

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    Somdipto Das

    2015-01-01

    Full Text Available Objectives: Oral leukoplakia is a nonscrappable whitish patch described as a potentially malignant disorder with high prevalence in India. Besides medicinal treatment, neodymium: Yttrium aluminum garnet (Nd: YAG laser is also used for the management of oral leukoplakia. This study evaluated the role of Nd: YAG laser in the management of oral leukoplakia and also investigated postoperative complications along with long-term prognosis of the disease. Settings and Designs: The study is a prospective cohort study conducted for 24 months (June 2011 to May 2013 in Lucknow. Materials and Methods: The study comprised of 42 patients, both male and female of Indian origin and diagnosed with oral leukoplakic lesions. Patients with biopsy proven squamous cell carcinoma and medically compromised are excluded from the study. All patients has undergone ablation of lesion by pulsed Nd: YAG laser and were followed after 24 h, 72 h, 1-week and then successively for 1, 3, 6 months and then 1 st and 2 nd postoperative years. Results: Pain and slough were evaluated by Wicoxon rank test (P = 0.0001 statistically significant which decreased from 24 h to 1-week and became nil in subsequent follow-ups. Similarly, McNemar′s test (P = 0.001 statistically significant was used for evaluation of burning sensation, paresthesia, infection and recurrences. Recurrence was noted in 2 patients but following the second application, there were no recurrences over the period of further follow-up. None of the patient suffered from an infection, paresthesia or anesthesia. Conclusion: Hence, Nd: YAG laser was found to be effective in ablating leukoplakia. It is convenient, economical with minimum complications and morbidities.

  19. Self-stabilized and dispersion-compensated passively mode-locked Yb:Yttrium aluminum garnet laser

    Science.gov (United States)

    Agnesi, A.; Guandalini, A.; Reali, G.

    2005-04-01

    Self-stabilized passive mode-locking of a diode-pumped Yb:yttrium aluminum garnet laser with a semiconductor saturable absorber was achieved using an off-phase-matching second-harmonic crystal. According to the numerical model, such a condition is accomplished by self-defocusing in the nonlinear crystal in the presence of positive intracavity dispersion. Robust mode locking with Fourier-limited 1.0-ps pulses was obtained, whereas mode locking, unassisted by the nonlinear crystal, yielded 2.2-ps pulses, with the laser operating near the edge of the stability region in order to minimize the saturation energy of the semiconductor device.

  20. ELECTRON MICROSCOPIC INVESTIGATION OF YTTRIUM ALUMINUM GARNET POWDERS Y3AL5O12, SYNTHESIZED BY SOL–GEL METHOD

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    A. E. Baranchikov

    2015-09-01

    Full Text Available Subject of Study. The paper presents results of characterization for neodymium doped yttrium aluminum garnet nanopowders - YAG:Nd3+ by the method of scanning electronic microscopy. Method. Synthesis of YAG:Nd3+ was carried out by sol-gel method from nitrate or acetate - nitrate solutions with addition of some organic compounds and ammonia as well. Such substances were used as the source ones: oxides of neodymium and yttrium with the content of the basic substance equal to 99.999 %; organic compounds: citric acid with the content of the basic substance not less than 99.0 %; ethylene glycol (99.5%; the ammonium lauryl sulfate (99.0 %; urea (99.0 % of Alfa Aesar, Fluka, Aldrich companies. Oxides of yttrium and neodymium (5 at. % were dissolved in 50% acetic acid, nitrate aluminum was added with a view to the resulting product Y2,85Nd0,15Al5,0O12, the solution was stirred and heated to 60С before reaching its transparency and uniformity. The weight of the portion corresponding to the stoichiometry YAG was 2.0 g. 50 % aqueous solutions of organic substances or 5% NH4OH in a weight ratio of 1:1 to the weight of the garnet were added in aqueous solutions, placed into glass cups. The solutions were thoroughly mixed first using a conventional stirrer, then on ultrasonic installation with simultaneous 60 С heating for 2 hours. Drying of solutions to the consistency of a powder or a thick gel was carried out at 110 С. Then the samples were placed into platinum cups and annealed in a tube furnace at 950 - 1050 С for the period from 0.5 to 2 hours. Additional annealing of the powders in the air at 950 - 1060С were carried out for the purpose of powders clarifying for residual amorphous carbon removal. Main Results. The synthesized powder precursors and powders after annealing were examined using a polarizing microscope to identify anisotropic crystalline phases. X-ray analysis of the synthesized samples was carried out on a DRON - 4 and UDR - 63

  1. Dislocation of polyfocal full-optics accommodative intraocular lens after neodymium-doped yttrium aluminum garnet capsulotomy in vitrectomized eye

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    Kyung Tae Kang

    2013-01-01

    Full Text Available We report a case of dislocation of WIOL-CF® polyfocal full-optics intraocular lens (IOL after neodymium-doped yttrium aluminum garnet (Nd: YAG laser capsulotomy in the vitrectomized eye. At 22 months before the dislocation of the IOL, a 55-year-old male patient underwent phacoemulsification with WIOL-CF® IOL implantation in a local clinic and 10 months after the cataract surgery the patient underwent pars plana vitrectomy, endolaser photocoagulation and 14% C 3 F 8 gas tamponade for the treatment of rhegmatogenous retinal detachment. At 9 months after the vitrectomy, the patient visited our clinic for a sudden decrease of vision after Nd: YAG capsulotomy in the local clinic. On fundus examination, the dislocated IOL was identified and the Nd: YAG capsulotomy site and the larger break, which is suspected to have been a route of the dislocation were observed in the posterior capsule.

  2. The use of Erbium: Yttrium-aluminum-garnet laser in cavity preparation and surface treatment: 3-year follow-up.

    Science.gov (United States)

    Buyukhatipoglu, Isil; Secilmis, Asli

    2015-01-01

    From the currently available choices, esthetic restorative materials for posterior teeth are limited to composite and ceramic restoration. Ceramic inlays/onlays are reliable solutions for both of these treatments. For successful treatment planning, usable ceramic and adhesive systems should be chosen by the dentist. Since the Federal Drug Administration approval of the erbium: Yttrium-aluminum-garnet (Er:YAG) laser-for caries removal, cavity preparation and the conditioning of tooth substance-in 1997, there have been many reports on the use of this technique in combination with composite resins. In addition, cavity pretreatment with the Er:YAG laser (laser etching) has been proposed as an alternative to acid etching of enamel and dentin. This case report presents the use of the Er:YAG in cavity preparation for composite resin restoration and surface treatment for ceramic onlay restoration of adjacent permanent molars.

  3. From electrocautery, balloon dilatation, neodymium-doped:yttrium-aluminum-garnet (Nd:YAG) laser to argon plasma coagulation and cryotherapy

    Science.gov (United States)

    Pickering, Edward M.; Lee, Hans J.

    2015-01-01

    Over the past decade, there has been significant advancement in the development/application of therapeutics in thoracic diseases. Ablation methods using heat or cold energy in the airway is safe and effective for treating complex airway disorders including malignant and non-malignant central airway obstruction (CAO) without limiting the impact of future definitive therapy. Timely and efficient use of endobronchial ablative therapies combined with mechanical debridement or stent placement results in immediate relief of dyspnea for CAO. Therapeutic modalities reviewed in this article including electrocautery, balloon dilation (BD), neodymium-doped:yttrium-aluminum-garnet (Nd:YAG) laser, argon plasma coagulation (APC), and cryotherapy are often combined to achieve the desired results. This review aims to provide a clinically oriented review of these technologies in the modern era of interventional pulmonology (IP). PMID:26807284

  4. The use of Erbium: Yttrium-aluminum-garnet laser in cavity preparation and surface treatment: 3-year follow-up

    Science.gov (United States)

    Buyukhatipoglu, Isil; Secilmis, Asli

    2015-01-01

    From the currently available choices, esthetic restorative materials for posterior teeth are limited to composite and ceramic restoration. Ceramic inlays/onlays are reliable solutions for both of these treatments. For successful treatment planning, usable ceramic and adhesive systems should be chosen by the dentist. Since the Federal Drug Administration approval of the erbium: Yttrium-aluminum-garnet (Er:YAG) laser-for caries removal, cavity preparation and the conditioning of tooth substance-in 1997, there have been many reports on the use of this technique in combination with composite resins. In addition, cavity pretreatment with the Er:YAG laser (laser etching) has been proposed as an alternative to acid etching of enamel and dentin. This case report presents the use of the Er:YAG in cavity preparation for composite resin restoration and surface treatment for ceramic onlay restoration of adjacent permanent molars. PMID:26038665

  5. High-efficiency Tm-doped yttrium aluminum garnet laser pumped with a wavelength-locked laser diode

    Science.gov (United States)

    Huang, H. Z.; Huang, J. H.; Liu, H. G.; Dai, S. T.; Weng, W.; Zheng, H.; Ge, Y.; Li, J. H.; Deng, J.; Yang, X.; Lin, W. X.

    2016-09-01

    We first demonstrate a high-efficiency composite Tm-doped yttrium aluminum garnet laser end-pumped with a narrow-linewidth laser diode, which was locked at a wavelength of 784.9 nm with volume Bragg gratings. The locked pump wavelength was experimentally determined by the excitation peak, which was also the absorption peak of a 3.5 at.% Tm:YAG crystal around 785 nm, for the improvement of laser efficiency under high-intensity pumping. Under an absorbed pump power of 24.64 W, a maximum output power of 11.12 W at 2018 nm was obtained, corresponding to an optical to optical conversion efficiency of 45.1% and a slope efficiency of 52.4%.

  6. Observation of multiple-harmonic radiation induced from a gold surface by picosecond neodymium-doped yttrium aluminum garnet laser pulses

    Energy Technology Data Exchange (ETDEWEB)

    Farkas, G.; Toth, C. (Research Institute for Solid-State Physics, P.O. Box 49, H-1525 Budapest (Hungary)); Moustaizis, S.D.; Papadogiannis, N.A.; Fotakis, C. (Foundation for Research and Technology, Hellas, P.O. Box 1527, Heraklion 711 10, Crete (Greece))

    1992-10-01

    Illuminating a gold surface by strong (5 GW/cm{sup 2}) picosecond neodymium-doped yttrium aluminum garnet laser pulses at grazing incidence, we observed a generation of coherent beams of both even and odd harmonics up to fifth order in the reflected direction with efficiencies 10{sup {minus}10--}10{sup {minus}13}. The observed decrease of the harmonic efficiencies with increasing harmonic order is much weaker than predicted by perturbative theories.

  7. Yttrium aluminum garnet (YAG) obtained by rare-earth mixed oxide (RE{sub 2}O{sub 3})

    Energy Technology Data Exchange (ETDEWEB)

    Castro, D.F.; Daguano, J.K.M.F.; Rodrigues Junior, D., E-mail: claudinei@demar.eel.usp.b [Universidade de Sao Paulo (EEL/USP), Lorena, SP (Brazil). Escola de Engenharia; Santos, C. [Centro Universitario de Volta Redonda (MEMAT/UNIFOA), RJ (Brazil); Suzuki, P.A. [Laboratorio Nacional de Luz Sincrotron (LNLS), Campinas, SP (Brazil); Silva, O.M.M. [Centro Tecnico Aeroespacial (CTA-IAE), Sao Jose dos Campos, SP (Brazil). Inst. de Atividades Espaciais. Div. de Materiais

    2010-07-01

    In this work, the substitution of commercial Y{sub 2}O{sub 3} by a rare earth mixed oxide, RE{sub 2}O{sub 3}, to form Yttrium aluminum Garnet-Y{sub 3}Al{sub 5}O{sub 12}, was investigated. Al{sub 2}O{sub 3}:Y{sub 2}O{sub 3} and Al{sub 2}O{sub 3}:RE{sub 2}O{sub 3} powder-mixtures, in a molar ratio of 60:40, were milled and subsequently cold uniaxially-pressed. Compacts were sintered at 1000, 1400 or 1600 deg C, for 120 minutes. RE{sub 2}O{sub 3} oxide was characterized by high-resolution synchrotron X-ray diffraction (HRXRD) and compared to Y{sub 2}O{sub 3}. X-ray diffraction pattern of the RE{sub 2}O{sub 3} indicates a true solid solution formation. Rietveld refinement of the sintered YAG and (RE)AG reveled a similar crystal structure to the YAGs obtained by the use of Al{sub 2}O{sub 3}-Y{sub 2}O{sub 3} or Al{sub 2}O{sub 3}-RE{sub 2}O{sub 3} respectively. Microstructural analysis of both, YAG or (RE)AG, revealed similar grain sizes of about 2.5 {mu}m besides mechanical properties, with hardness of 400HV and fracture toughness of 3.8MPa.m1/2. It could be, thus, demonstrated that pure Y{sub 2}O{sub 3} can be substituted by the rare-earth solid solution, RE{sub 2}O{sub 3}, in the formation YAGs, presenting similar microstructural and mechanical properties. (author)

  8. Effect of the ion-beam bombardment and annealing temperature on sol-gel derived yttrium aluminum oxide film as liquid crystal alignment layer

    Science.gov (United States)

    Jeong, Hae-Chang; Heo, Gi-Seok; Kim, Eun-Mi; Lee, Ju Hwan; Han, Jeong-Min; Seo, Dae-Shik

    2017-02-01

    We demonstrated a homogeneous liquid-crystal (LC) alignment state on yttrium aluminum oxide (YAlO) films, where the alignment was induced by ion-beam (IB) irradiation. Topographical analysis was performed by atomic force microscopy as a function of annealing temperature. Higher annealing temperatures yielded a smoother surface, accompanied by reduced light scattering. Transparency in the visible region increased on the surface fabricated at higher annealing temperatures. LC alignment mechanism was determined by X-ray diffraction (XRD) analysis. Moreover, IB-irradiated YAlO films annealed at temperatures greater than 200 °C exhibited good thermal stability and low capacitance-voltage hysteresis. The IB-irradiated YAlO films are suitable as alternative alignment layers in advanced LC display applications.

  9. Relationship between Microstructure Evolution and the Luminescent Properties of Eu3+-doped Yttrium Aluminum Garnet and Y2O3 Nano-powders

    Institute of Scientific and Technical Information of China (English)

    Jie Zhang; Yongyi Gao; Junjie Xiao; Changfu Xu; Yunxin Liu; Qibin Yang

    2013-01-01

    Eu3+-doped yttrium aluminum garnet (YAG) and Y2O3 composite phase nanoparticles were synthesized using a modified hydrothermal method.Sintering was performed at 800 ℃,which is considerably lower than the sintering temperature used in the conventional method.Y3+ in YAG and Y2O3 was partially substituted with Na+ by adding NaNO3 into the solution during sample synthesis.The microstructures and phase transformation process were characterized through X-ray diffraction,scanning electron microscopy,and transmission electron microscopy.The obtained results verified that the addition of Na+ promoted crystallinity and grain growth of the three phases,namely,Y2O3,Y4Al2O9,and Y3AlsO12.Highly efficient luminescence properties excited by 254 and 365 nm ultraviolet were achieved.In conclusion,the remarkable enhancement of the luminescence intensity with the addition of Na+ should be attributed to grain growth and improvement of crystallinity.

  10. Pupil-occluding organized hyphema anterior to the intraocular lens treated by neodymium: yttrium-aluminum-garnet laser: a case report

    Science.gov (United States)

    Kim, Moosang; Lee, Seung-Jun; Han, Sang Beom; Yang, Hee Kyung; Hyon, Joon Young

    2016-01-01

    We report, to our best knowledge, the first case of treatment of pupil-occluding postoperative organized hyphema anterior to the intraocular lens (IOL) using neodymium: yttrium-aluminum-garnet (Nd:YAG) laser. A 78-year-old Asian female underwent uneventful cataract operation. She had been taking aspirin, which she discontinued 1 week before surgery. Iris prolapse occurred at the end of the surgery, which led to intracameral bleeding. Two weeks later, her best-corrected visual acuity was hand motion. Although hyphema had decreased, pupil-occluding organized hematoma had formed anterior to the IOL. The blood clot anterior to the IOL was removed using Nd:YAG laser. One week later, although the hematoma anterior to the IOL resolved, endocapsular hematoma was observed, which was dispersed with Nd:YAG laser posterior capsulotomy. Two weeks later, her best-corrected visual acuity improved to 20/60. There was no complication associated with Nd:YAG laser. In conclusion, pupil-occluding organized hyphema anterior to the IOL can occur as a complication of cataract surgery, in which Nd:YAG laser can be a useful treatment option. PMID:27462181

  11. A Retrospective Study on the Characteristics of Treating Nevus of Ota by 1064-nm Q-switched Neodymium-doped Yttrium Aluminum Garnet Laser

    Science.gov (United States)

    Liu, Yanting; Zeng, Weihui; Geng, Songmei

    2016-01-01

    Background: The Q-switched neodymium-doped yttrium aluminum garnet (QS Nd:YAG) laser has a significant effect in treating nevus of Ota, but there is lack of a retrospective study about the characteristics of efficacy. Aims and Objectives: To retrospectively analyze the correlation between the clinical characteristics and efficacy, complications, recurrence of QS Nd:YAG laser in treating nevus of Ota. Materials and Methods: One hundred and seventy-one Chinese patients (144 female, 27 male) of nevus of Ota were treated with the 1064-nm QS Nd:YAG laser. All cases were treated with fluencies of 4–8 J/cm2 and a spot size of 2–4 mm. Clinical photographs were taken before every treatment and patients were followed up by their clinicians. Results: One hundred and forty-five patients (84.8%) acquired more than 75% improvement with an average of 4.6 sessions. The treatment effect has no significant correlation with sex (P > 0.05). The blue-black and brown lesions improved more than the light-brown (P nevus of Ota. The efficacy correlated with lesion color, which is meaningful to estimate the prognosis. PMID:27293272

  12. Efficacy of the Q-switched Neodymium: Yttrium Aluminum Garnet Laser in the Treatment of Blue-black Amateur and Professional Tattoos

    Science.gov (United States)

    Lakshmi, Chembolli; Krishnaswamy, Gayathri

    2015-01-01

    Background: Q-switched neodymium: yttrium aluminum garnet (Nd: YAG) laser at a wavelength of 1064 nm primarily targets dermal melanin and black tattoo ink. Recent studies have shown that this laser is effective in treating black tattoos. There are few studies conducted in India for the same. Aim: The aim was to assess the effectiveness of Q-switched Nd: YAG laser (QSNYL) in the treatment of blue-black tattoos following 3 treatment sessions. Materials and Methods: This study, a prospective interventional study included a total of 12 blue-black tattoos. Following informed consent for the procedure, as well as for photographs, a questionnaire was administered, and improvement perceived by the patient was recorded. In addition, global assessment score (GAS) by a blinded physician was also recorded. Photographs were taken at baseline and at every follow-up. Each patient underwent three treatment sessions with 1064 nm QSNYL at 4–6 weekly intervals. Fluences ranged from 1.8 to 9 J/cm2. The follow-up was done monthly for 4 months from the first treatment session. The response was assessed by patient assessment (PA) and GAS by comparing photographs. Results: After three treatment sessions, although no patient achieved clearance, most patients showed good response with few adverse effects. An average of 64.1% (GAS) and 54.2% (PA) improvement was observed in 12 tattoos. Tattoos more than 10-year-old showed quicker clearing than those less than 10-year-old. Amateur tattoos also showed a better response in comparison to professional tattoos. Conclusion: Totally, 1064 nm QSNYL is safe and effective for lightening blue-black tattoos in pigmented Indian skin. All patients achieved near complete clearance following the continuation of treatment (an average of six sessions) although this was spaced at longer intervals. PMID:26677271

  13. A comparative study of pressure-dependent emission characteristics in different gas plasmas induced by nanosecond and picosecond neodymium-doped yttrium aluminum garnet (Nd:YAG) lasers.

    Science.gov (United States)

    Abdulmadjid, Syahrun Nur; Idris, Nasrullah; Marpaung, Alion Mangasi; Pardede, Marincan; Jobiliong, Eric; Hedwig, Rinda; Suliyanti, Maria Margaretha; Ramli, Muliadi; Suyanto, Heri; Kagawa, Kiichiro; Tjia, May On; Lie, Zener Sukra; Lie, Tjung Jie; Kurniawan, Hendrik Koo

    2013-11-01

    An experimental study has been performed on the pressure-dependent plasma emission intensities in Ar, He, and N2 surrounding gases with the plasma induced by either nanosecond (ns) or picosecond (ps) yttrium aluminum garnet laser. The study focused on emission lines of light elements such as H, C, O, and a moderately heavy element of Ca from an agate target. The result shows widely different pressure effects among the different emission lines, which further vary with the surrounding gases used and also with the different ablation laser employed. It was found that most of the maximum emission intensities can be achieved in Ar gas plasma generated by ps laser at low gas pressure of around 5 Torr. This experimental condition is particularly useful for spectrochemical analysis of light elements such as H, C, and O, which are known to suffer from intensity diminution at higher gas pressures. Further measurements of the spatial distribution and time profiles of the emission intensities of H I 656.2 nm and Ca II 396.8 nm reveal the similar role of shock wave excitation for the emission in both ns and ps laser-induced plasmas, while an additional early spike is observed in the plasma generated by the ps laser. The suggested preference of Ar surrounding gas and ps laser was further demonstrated by outperforming the ns laser in their applications to depth profiling of the H emission intensity and offering the prospect for the development of three-dimensional analysis of a light element such as H and C.

  14. A retrospective study on the characteristics of treating nevus of ota by 1064-nm q-switched neodymium-doped yttrium aluminum garnet laser

    Directory of Open Access Journals (Sweden)

    Yanting Liu

    2016-01-01

    Full Text Available Background: The Q-switched neodymium-doped yttrium aluminum garnet (QS Nd:YAG laser has a significant effect in treating nevus of Ota, but there is lack of a retrospective study about the characteristics of efficacy. Aims and Objectives: To retrospectively analyze the correlation between the clinical characteristics and efficacy, complications, recurrence of QS Nd:YAG laser in treating nevus of Ota. Materials and Methods: One hundred and seventy-one Chinese patients (144 female, 27 male of nevus of Ota were treated with the 1064-nm QS Nd:YAG laser. All cases were treated with fluencies of 4–8 J/cm2 and a spot size of 2–4 mm. Clinical photographs were taken before every treatment and patients were followed up by their clinicians. Results: One hundred and forty-five patients (84.8% acquired more than 75% improvement with an average of 4.6 sessions. The treatment effect has no significant correlation with sex (P > 0.05. The blue-black and brown lesions improved more than the light-brown (P < 0.05. Hyperpigmentation affected two (1.2% of the patients and hypopigmentation affected one patient (0.6%. No other adverse effect was observed. Recurrence was seen in two patients (1.2%. Conclusion: The 1064-nm QS Nd:YAG laser is effective with rare complications and recurrence in the treatment of nevus of Ota. The efficacy correlated with lesion color, which is meaningful to estimate the prognosis.

  15. Skin healing and collagen changes of rats after fractional erbium:yttrium aluminum garnet laser: observation by reflectance confocal microscopy with confirmed histological evidence.

    Science.gov (United States)

    Yang, Jing; Wang, Sha; Dong, Liyun; An, Xiangjie; Li, Yan; Li, Jun; Tu, Yating; Tao, Juan

    2016-08-01

    The fractional erbium:yttrium aluminum garnet (Er:YAG) laser is widely applied. Microstructural changes after laser treatment have been observed with histopathology. Epidermal and dermal microstructures have also been analyzed using reflectance confocal microscopy (RCM). However, no studies have compared these two types of microstructural changes in the same subject at multiple time points after irradiation, and it is unclear if these two types of changes are consistent. We use RCM to observe the effect of different laser energies on skin healing and collagen changes in the skin of Sprague-Dawley rats that had been irradiated by fractional Er:YAG lasering at different energies. RCM was used to observe skin healing and detect collagen changes at different time points. Collagen changes were observed using hematoxylin and eosin (H&E) staining and quantitatively analyzed by western blot. RCM showed that, irrespective of laser energy, microscopic treatment zones (MTZs) were larger at 1 day after irradiation. The MTZs then reduced in size from 3 to 7 days after irradiation. The higher the energy, the larger the MTZ area. The amount of collagen also increased with time from 1 day to 8 weeks. However, the increase in the collagen amount on both RCM and H&E staining was not influenced by the laser energy. Western blotting confirmed that the amount of type I and type III collagens increased over time, but there were no significant differences between the different energy groups (p > 0.05). In conclusion, RCM is a reliable technique for observing and evaluating skin healing and collagen expression after laser irradiation.

  16. Efficacy of the q-switched neodymium: Yttrium aluminum garnet laser in the treatment of blue-black amateur and professional tattoos

    Directory of Open Access Journals (Sweden)

    Chembolli Lakshmi

    2015-01-01

    Full Text Available Background: Q-switched neodymium: yttrium aluminum garnet (Nd: YAG laser at a wavelength of 1064 nm primarily targets dermal melanin and black tattoo ink. Recent studies have shown that this laser is effective in treating black tattoos. There are few studies conducted in India for the same. Aim: The aim was to assess the effectiveness of Q-switched Nd: YAG laser (QSNYL in the treatment of blue-black tattoos following 3 treatment sessions. Materials and Methods: This study, a prospective interventional study included a total of 12 blue-black tattoos. Following informed consent for the procedure, as well as for photographs, a questionnaire was administered, and improvement perceived by the patient was recorded. In addition, global assessment score (GAS by a blinded physician was also recorded. Photographs were taken at baseline and at every follow-up. Each patient underwent three treatment sessions with 1064 nm QSNYL at 4-6 weekly intervals. Fluences ranged from 1.8 to 9 J/cm 2 . The follow-up was done monthly for 4 months from the first treatment session. The response was assessed by patient assessment (PA and GAS by comparing photographs. Results: After three treatment sessions, although no patient achieved clearance, most patients showed good response with few adverse effects. An average of 64.1% (GAS and 54.2% (PA improvement was observed in 12 tattoos. Tattoos more than 10-year-old showed quicker clearing than those less than 10-year-old. Amateur tattoos also showed a better response in comparison to professional tattoos. Conclusion: Totally, 1064 nm QSNYL is safe and effective for lightening blue-black tattoos in pigmented Indian skin. All patients achieved near complete clearance following the continuation of treatment (an average of six sessions although this was spaced at longer intervals.

  17. Laser intervention on trabeculo-Descemet′s membrane after resistant viscocanalostomy: Selective 532 nm gonioreconditioning or conventional 1064 nm neodymium-doped yttrium aluminum garnet laser goniopuncture?

    Directory of Open Access Journals (Sweden)

    Huri Sabur

    2016-01-01

    Full Text Available Purpose: To compare the results of conventional 1064 nm neodymium-doped yttrium-aluminum garnet laser goniopuncture (Nd:YAG-GP and selective 532 nm Nd:YAG laser (selective laser trabeculoplasty [SLT]  gonioreconditioning (GR on trabeculo-Descemet′s membrane in eyes resistant to viscocanalostomy surgery. Methods: Thirty-eight eyes of 35 patients who underwent laser procedure after successful viscocanalostomy surgery were included in the study. When postoperative intraocular pressure (IOP was above the individual target, the eyes were scheduled for laser procedure. Nineteen eyes underwent 532 nm SLT-GR (Group 1, and the remaining 19 eyes underwent conventional 1064 nm Nd:YAG-GP (Group 2. IOPs before and after laser (1 week, 1 month, 3 months, 6 months, 1 year, and last visit, follow-up periods, number of glaucoma medications, and complications were recorded for both groups. Results: Mean times from surgery to laser procedures were 17.3 ± 9.6 months in Group 1 and 13.0 ± 11.4 months in Group 2. Mean IOPs before laser procedures were 21.2 ± 1.7 mmHg in Group 1 and 22.8 ± 1.9 mmHg in Group 2 (P = 0.454. Postlaser IOP measurements of Group 1 were 12.1 ± 3.4 mmHg and 13.8 ± 1.7 mmHg in the 1 st week and last visit, respectively; in Group 2, these measurements were 13.6 ± 3.7 mmHg and 14.9 ± 4.8 mmHg, respectively. There were statistically significant differences (P 0.05. Mean follow-up was 16.6 ± 6.4 months after SLT-GR and 18.9 ± 11.2 months after Nd:YAG-GP. Conclusions: While conventional Nd:YAG-GP and SLT-GR, a novel procedure, are both effective choices in eyes resistant to viscocanalostomy, there are fewer complications with SLT-GR. SLT-GR can be an alternative to conventional Nd:YAG-GP.

  18. Efficacy and Safety of 120-W Thulium:Yttrium-Aluminum-Garnet Vapoenucleation of Prostates Compared with Holmium Laser Enucleation of Prostates for Benign Prostatic Hyperplasia

    Institute of Scientific and Technical Information of China (English)

    Kai Hong; Yu-Qing Liu; Jian Lu; Chun-Lei Xiao; Yi Huang; Lu-Lin Ma

    2015-01-01

    Background:This study compared the efficacy and safety between 120-W thulium:yttrium-aluminum-garnet (Tm:YAG) vapoenucleation of prostates (ThuVEP) and holmium laser enucleation of prostates (HoLEP) for patients with lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH).Methods:A retrospective analysis of 88 consecutive patients with symptomatic BPH was carried out,who underwent either 120-W ThuVEP or HoLEP nonrandomly.Patient demographics and peri-operative and 12-month follow-up data were analyzed with the International Prostate Symptom Score (IPSS),quality of life (QoL) score,maximum flow rate (Qmax),postvoid residual urine volume (PVR),and rates of peri-operative and late complications.Results:The patients in each group showed no significant difference in preoperative parameters.Compared with the HoLEP group,patients in the 120-W ThuVEP group required significantly shorter time for laser enucleation (58.3 ± 12.8 min vs.70.5 ± 22.3 min,P =0.003),and resulted in a significant superiority in laser efficiency (resected prostate weight/laser enucleation time) for 120-W Tm:YAG lasercompared to holmium:YAG laser (0.69 ± 0.18 vs.0.61 ± 0.19,P =0.048).During 1,6,and 12 months of follow-ups,the procedures did not demonstrate a significant difference in IPSS,QoL score,Qmax,or PVR (P > 0.05).Mean peri-operative decrease of hemoglobin in the HoLEP group was similar to the ThuVEP group (17.1 ± 12.0 g/L vs.15.2 ± 10.1 g/L,P =0.415).Early and late incidences of complications were low and did not differ significantly between the two groups of 120-W ThuVEP and HoLEP patients (P > 0.05).Conclusions:120-W ThuVEP and HoLEP are potent,safe and efficient modalities of minimally invasive surgeries for patients with LUTS due to BPH.Compared with HoLEP,120-W ThuVEP offers advantages of reduction of laser enucleation time and improvement of laser efficiency.

  19. Comparative study of diode laser versus neodymium-yttrium aluminum: garnet laser versus intense pulsed light for the treatment of hirsutism

    Directory of Open Access Journals (Sweden)

    Neerja Puri

    2015-01-01

    Full Text Available Introduction: Lasers are widely used for the treatment of hirsutism. But the choice of the right laser for the right skin type is very important. Before starting with laser therapy, it is important to assess the skin type, the fluence, the pulse duration and the type of laser to be used. Aims: To compare the efficacy and side effects of Diode laser, Neodymium-yttrium aluminum - garnet (Nd: YAG laser and intense pulsed light (IPL on 30 female patients of hirsutism. Materials and Methods: Thirty female patients with hirsutism were selected for a randomised controlled study. The patients were divided into three groups of 10 patients each. In group I patients diode laser was used, in group II patients long pulsed Nd: YAG laser was used and in group III, IPL was used. The patients were evaluated and result graded according to a 4-point scale as excellent, >75% reduction; good, 50-75% reduction; fair; 25-50% reduction; and poor, <25% reduction in hair density. Results: It was seen that the percentage of hair reduction after two sessions of treatment was maximum (40% in the diode laser group, followed by 35% hair reduction in the Nd: Yag laser group and 10% hair reduction in the IPL group. The percentage of hair reduction after four sessions of treatment was maximum (64% in the diode laser group, followed by 62% hair reduction in the Nd: Yag laser group and 48% hair reduction in the IPL group. The percentage of hair reduction after eight sessions of treatment was maximum (92% in the diode laser group, followed by 90% hair reduction in the Nd: YAG group and 70% hair reduction in the IPL group. Conclusions: To conclude for the Indian skin with dark hairs, the diode laser still stands the test of time. But, since the diode laser has a narrow margin of safety, proper pre and post-procedure cooling is recommended. Although, the side effects of Nd: YAG laser are less as compared to the diode laser, it is less efficacious as compared to the diode laser.

  20. Kinetic characteristics of the luminescence decay for industrial yttrium-gadolinium-aluminium garnet based phosphors

    OpenAIRE

    Lisitsyn, Viktor Mikhailovich; Stepanov, Sergey Aleksandrovich; Valiev, Damir Talgatovich; Vishnyakova, E. A.; Abdullin, H. A.; Marhabaeva, A. A.; Tulegenova, A. T.

    2016-01-01

    The spectral and decay kinetic characteristics of pulse cathodoluminescence and photoluminescence of phosphors based on yttrium-gadolinium-aluminum garnet were investigated using pulsed optical time resolved spectroscopy.

  1. Efficacy and safety of fractional Q-switched 1064-nm neodymium-doped yttrium aluminum garnet laser in the treatment of melasma in Chinese patients.

    Science.gov (United States)

    Yue, Baishuang; Yang, Qianli; Xu, Jinhua; Lu, Zhong

    2016-11-01

    Melasma is an acquired disorder of symmetrical hyperpigmentation commonly seen in patients with Fitzpatrick skin types III and IV. Various novel therapeutic modalities have emerged to treat melasma. The large-spot low-fluence QS Nd:YAG laser has been widely used in Asia; however, the modality needs to be optimized because of the high recurrence rate. The objective of this study is to explore the clinical efficacy and safety of fractional-mode (Pixel) Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG) 1064-nm laser for treatment of melasma in Chinese patients. Twenty-seven patients were enrolled and completed all the treatment sessions and the 12-week follow-up. All were treated using the fractional-mode Pixel QS Nd:YAG (1064 nm) laser for eight sessions at a 2-3-week interval. Clinical photographs were taken using the Visia skin analysis imaging system. Two blinded assessors evaluated melasma area and severity index (MASI) scores before and 4 weeks after the final session. Melanin index (MI) and erythema index (EI) was measured before each treatment visit and after the final treatment. The degree of pigmentation and erythema was assessed using a tristimulus color analyzer. Physicians' global assessment (PGA) and patients' self-assessment were taken as the subjective assessments. Wilcoxon signed-rank test was performed to evaluate clinical response. Recurrence rate were also evaluated. Mean MASI scores decreased from 12.84 ± 6.89 to 7.29 ± 4.15 after treatment (p = 0.000). Seventy percent of patients got moderate to good improvements after all the treatment. Mean MI decreased significantly from 56.52 ± 23.35 to 32.75 ± 12.91 (p = 0.000). L value increased from 59.21 ± 2.22 before treatment to 61.60 ± 2.40 (p = 0.000) after therapy. The mean score of PGA was 3.76 ± 0.71, indicating a "moderate" clearance of the lesion. In patients' self-evaluations, 70 % of the patients rated the result as "good" to

  2. Induction of melasma by 1064-nm Q-switched neodymium:yttrium-aluminum-garnet laser therapy for acquired bilateral nevus of Ota-like macules (Hori nevus): A study on related factors in the Chinese population.

    Science.gov (United States)

    Wang, Ben; Xie, Hong-Fu; Tan, Jun; Xie, Hong-Ju; Xu, Lin-Yong; Ding, Rong; Liu, Fang-Fen; Chen, Xiang; Jian, Dan; Li, Ji

    2016-06-01

    Laser treatment has emerged as a common treatment modality for acquired bilateral nevus of Ota-like macules (ABNOM). To identify the ratio of melasma induction and exacerbation before and after laser therapy for ABNOM and to observe the risk factors related to the induction and exacerbation of melasma by laser therapy, we analyzed related factors of 1268 adult Chinese patients who underwent 1064-nm Q-switched neodymium:yttrium-aluminum-garnet (Nd:YAG) laser (QNYL) treatment using case series and case-control studies. Overall, 24.0% of the ABNOM patients had mixed melasma. Among the ABNOM patients without melasma, after laser therapy the development of melasma was more frequently noted in patients older than 35 years (P < 0.0001), as well in patients whose ABNOM was less than 10 cm(2) (P = 0.027), ABNOM were light (similar to yellow-brown) in color (P = 0.021) and skin types were closer to type IV (P < 0.0001). New melasma lesions also appeared most frequently in the zygomatic region (P < 0.0001). Among the ABNOM patients with melasma, 89.5% experienced worsening of their melasma, irrespective of their related factors above. We concluded that the risk of inducing melasma is great after 1064-nm QNYL treatment in ABNOM patients, and particularly in the patients with both ABNOM and melasma. ABNOM patients should be treated as early as possible and before the age of 35 years.

  3. Prospective Comparison of Dual Wavelength Long-Pulsed 755-nm Alexandrite/1,064-nm Neodymium:Yttrium-Aluminum-Garnet Laser versus 585-nm Pulsed Dye Laser Treatment for Rosacea

    Science.gov (United States)

    Seo, Hyun-Min; Kim, Jung-In; Kim, Han-Saem; Choi, Young-Jun

    2016-01-01

    Background Rosacea treatments including oral/topical medications and laser therapy are numerous but unsatisfactory. Objective To compare the effectiveness of the dual wavelength long-pulsed 755-nm alexandrite/1,064-nm neodymium: yttrium-aluminum-garnet laser (LPAN) with that of 585-nm pulsed dye laser (PDL) for rosacea. Methods This was a randomized, single-blinded, comparative study. Full face received four consecutive monthly treatments with LPAN or PDL, followed-up for 6 months after the last treatment. Erythema index was measured by spectrophotometer, and digital photographs were evaluated by consultant dermatologists for physician's global assessment. Subjective satisfaction surveys and adverse effects were recorded. Results Forty-nine subjects with rosacea enrolled and 12 dropped out. There were no significant differences between LPAN and PDL in the mean reduction of the erythema index (p=0.812; 3.6% vs. 2.8%), improvement of physician's global assessment (p=1.000; 88.9% vs. 89.5%), and subject-rated treatment satisfaction (p=0.842; 77.8% vs. 84.2%). PDL showed more adverse effects including vesicles than LPAN (p=0.046; 26.3% vs. 0.0%). No other serious or permanent adverse events were observed in both treatments. Conclusion Both LPAN and PDL may be effective and safe treatments for rosacea. PMID:27746641

  4. An in vitro evaluation of the responses of human osteoblast-like SaOs-2 cells to SLA titanium surfaces irradiated by erbium:yttrium-aluminum-garnet (Er:YAG) lasers.

    Science.gov (United States)

    Ayobian-Markazi, Nader; Fourootan, Tahereh; Zahmatkesh, Atieh

    2014-01-01

    Erbium:yttrium-aluminum-garnet (Er:YAG) laser treatment is an effective option for the removal of bacterial plaques. Many studies have shown that Er:YAG lasers cannot re-establish the biocompatibility of titanium surfaces. The aim of this study was to evaluate the responses of the human osteoblast-like cell line, SaOs-2, to sand-blasted and acid-etched (SLA) titanium surface irradiation using different energy settings of an Er:YAG laser by examining cell viability and morphology. Forty SLA titanium disks were irradiated with an Er:YAG laser at a pulse energy of either 60 or 100 mJ with a pulse frequency of 10 Hz under water irrigation and placed in a 24-well plate. Human osteoblast-like SaOs-2 cells were seeded onto the disks in culture media. Cells were then kept in an incubator with 5% carbon dioxide at 37 °C. Each experimental group was divided into two smaller groups to evaluate cell morphology by scanning electron microscope and cell viability using 3-4,5-dimethylthiazol 2,5-diphenyltetrazolium bromide test. In both the 60 and the 100 mJ experimental groups, spreading morphologies, with numerous cytoplasmic extensions, were observed prominently. Similarly, a majority of cells in the control group exhibited spreading morphologies with abundant cytoplasmic extensions. There were no significant differences among the laser and control groups. The highest cell viability rate was observed in the 100 mJ laser group. No significant differences were observed between the cell viability rates of the two experimental groups (p = 1.00). In contrast, the control group was characterized by a significantly lower cell viability rate (p SLA titanium surfaces. In fact, modifying SLA surfaces with Er:YAG lasers improved the biocompatibility of these surfaces.

  5. Effects of two erbium-doped yttrium aluminum garnet lasers and conventional treatments as composite surface abrasives on the shear bond strength of metal brackets bonded to composite resins

    Science.gov (United States)

    Sobouti, Farhad; Dadgar, Sepideh; Sanikhaatam, Zahra; Nateghian, Nazanin; Saravi, Mahdi Gholamrezaei

    2016-01-01

    Background: Bonding brackets to dental surfaces restored with composites are increasing. No studies to date have assessed the efficacy of laser irradiation in roughening of composite and the resulted shear bond strength (SBS) of the bonded bracket. We assessed, for the 1st time, the efficacy of two laser beams compared with conventional methods. Materials and Methods: Sixty-five discs of light-cured composite resin were stored in deionized distilled water for 7 days. They were divided into five groups of 12 plus a group of five for scanning electron microscopy (SEM): Bur-abrasion followed by phosphoric acid etching (bur-PA), hydrofluoric acid conditioning (HF), sandblasting, 3 W and 2 W erbium-doped yttrium aluminum garnet laser irradiation for 12 s. After bracket bonding, specimens were water-stored (24 h) and thermocycled (500 cycles), respectively. SBS was tested at 0.5 mm/min crosshead speed. The adhesive remnant index (ARI) was scored under ×10 magnification. SEM was carried out as well. Data were analyzed using analysis of variance (ANOVA), Kruskal–Wallis, Tukey, Dunn, one-sample t-test/Wilcoxon tests, and Weibull analysis (α =0.05). Results: The SBS values (megapascal) were bur-PA (11.07 ± 1.95), HF (19.70 ± 1.91), sandblasting (7.75 ± 1.10), laser 2 W (15.38 ± 1.38), and laser 3 W (20.74 ± 1.73) (compared to SBS = 6, all P = 0.000). These differed significantly (ANOVA P = 0.000) except HF versus 3 W laser (Tukey P > 0.05). ARI scores differed significantly (Kruskal–Wallis P = 0.000), with sandblasting and 2 W lasers having scores inclined to the higher end (safest debonding). Weibull analysis implied successful clinical outcome for all groups, except for sandblasting with borderline results. Conclusion: Considering its high efficacy and the lack of adverse effects bound with other methods, the 3 W laser irradiation is recommended for clinical usage. PMID:26998473

  6. Clinical observation on treatment of acute wisdom tooth pericoronitis with neodymium:Yttrium-Aluminum-garnet Laser%Nd:YAG激光治疗急性局限性智齿冠周炎的临床观察

    Institute of Scientific and Technical Information of China (English)

    栗洪师; 李冬霞; 柯杰

    2015-01-01

    Objective:To study the efficacy of neodymium:yttrium- aluminum-garnet laser of curing acutewisdom tooth pericoronitis,comparing with iodine glycerine. Method:57 cases of acute wisdom tooth pericoronitis were selected and randomly separated into 3 groups,whose local parts were washed with 3 % hydrogen peroxide,and physiological saline consecutively,and dried clearly. For patients in group A test sides were treated with the Nd:YAG laser(1064 nm,MSP,1.5 W,100 mJ,15 Hz). Clinical assessments (total effective rate of local treatment and visual analog scale of pain) were performed pre-treatment and at 4 days post treatment,B,minocycline hydrochloride ointment was injected on their infected areas once. Patients in Group C were treated with 2%iodine glycerine once everyday in 3 days. Efficacy of all experimental treatments were observed at the 4th day. Result:The symptoms of group A an B were mitigated obviously,whose ratio of effectiveness was 89.47%and 78.95 %respectively,without significant difference(P>0.05),and were all better than that of group C(63.16%,P<0.01 P<0.05.). Conclusion:Nd:YAG laser is good in curing acute wisdom tooth pericoronitis.%目的:观察口腔钕激光(neodymium:yttrium-aluminum-garnet,Nd:YAG)治疗急性局限性智齿冠周炎的临床疗效。方法:选取114例急性局限性智齿冠周炎患者,局部用3%过氧化氢和生理盐水交替冲洗后棉球擦干,随机分为3组,A组Nd:YAG激光组(n=38):Nd:YAG激光低强度治疗(LLLT)模式,具体选择参数:MSP,1.5 W,100 mJ,15 Hz,非接触局部移动照射病变区肿胀软组织10 min,B组(n=38):局部肿胀龈袋注人适量盐酸米诺环素软膏1次;C组(n=38):局部龈袋置入2%碘甘油,1次/d×3 d。所有治疗组均未全身用药,第4 d观察疗效。结果:和C组比较,A,B组局部炎性肿胀症状均有明显改善,总有效率分别为89.47%和78.95%,A,B两组间

  7. Carbochlorination of yttrium oxide

    Energy Technology Data Exchange (ETDEWEB)

    Gaviria, J.P., E-mail: gaviriaj@cab.cnea.gov.ar [Division Cinetica Quimica - Complejo Tecnologico Pilcaniyeu, Centro Atomico Bariloche - Comision Nacional de Energia Atomica, Av. Bustillo km 9500 (8400), S.C. de Bariloche, Rio Negro (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (Argentina); Bohe, A.E. [Division Cinetica Quimica - Complejo Tecnologico Pilcaniyeu, Centro Atomico Bariloche - Comision Nacional de Energia Atomica, Av. Bustillo km 9500 (8400), S.C. de Bariloche, Rio Negro (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas (Argentina); Centro Regional Universitario Bariloche, Universidad Nacional del Comahue (Argentina)

    2010-09-20

    The reaction of chlorination of a mixture composed by Y{sub 2}O{sub 3} and sucrose carbon was studied by thermogravimetry over a temperature range of 550-950 {sup o}C. The reaction proceeds through several successive stages. The first of them is the formation of solid yttrium oxychloride (YOCl) and subsequently the YOCl is carbochlorinated to produce YCl{sub 3} (solid or liquid, depending on the temperature) in two stages. The stoichiometries of the first stage and the global reaction were estimated by mass balances, taking into account the chlorine adsorbed by the remainder carbon. The results showed that the reactions involved progress with the formation of CO{sub 2} and CO in the temperature range of 600-775 {sup o}C. The interaction between sucrose carbon and chlorine was analyzed by thermogravimetry in order to quantify the amount of chlorine which is adsorbed on its surface. It was studied the effect of the temperature and initial mass of carbon. The morphological analysis performed by SEM of partially reacted samples showed that the formation of YOCl proceeds through a mechanism of nucleation and growth. For temperatures above 715 {sup o}C the final product of the carbochlorination is liquid YCl{sub 3}, whose evaporation is observed in the thermogravimetry. The evaporation kinetics was analyzed in argon atmosphere and from the thermogravimetric curves was determined a value of 250 kJ/mol for the heat of evaporation of YCl{sub 3}. This value is consistent with a partial dimerization of the gaseous chloride.

  8. Preparation of nanometer yttrium oxide

    Institute of Scientific and Technical Information of China (English)

    HUO; Cheng-zhang; LIU; Zhi-qiang; LIANG; Zhen-feng; LI; Xing-ying

    2005-01-01

    The nanometer yttrium oxides were obtained through precipitation in aqueous solution by reaction with ammonium bicarbonate. The reaction between yttrium chloride and ammonium bicarbonate, the effect of surfactants on particle size and the methods of controlling agglomeration were studied. Compared to other methods, the method of controlling the agglomeration by adding surfactant is one of the best methods for controlling the agglomeration of nanometer particles in wetchemical process. Increasing surfactants in process of precipitation deduced particle size, obtained narrow size distribution of primary particles. As for the concentration range studied, excess surfactants increased the particle size on the contrary. Characteristics of the thermal decomposition of yttrium carbonate were studied. It indicated that the approximate chemical composition of the precipi tate was Y(OH)Clx (CO3)(1-x/2) · 3H2O,the cubic Y2O3 was obtained above 600℃ , the specific surface and the remain chloride of nanometer Y2O3 was decreased with calcinating temperature rising. The spherical nanometer yttrium oxide was gained with primary particles<50 nm,agglomerate distribution D50 < 150 nm, BET> 35 m2/g, agglomerate constant (D50/DBET ) <6.

  9. Preliminary results on a new method for producing yttrium phosphorous microspheres.

    Science.gov (United States)

    Ghahramani, M R; Garibov, A A; Agayev, T N

    2014-09-01

    This paper reports on a new method to embed phosphorus particles into the matrix of yttrium aluminum silicate microspheres. Yttrium phosphorus glass microspheres about 20µm in size were obtained when an aqueous solution of YCl3 and AlCl3 were added to tetraethyl orthosilicate (TEOS) (phosphoric acid was used to catalyze the hydrolysis and condensation of TEOS) and was pumped into silicone oil under constant stirring. The shapes of the particles produced by this method are regular and nearly spheric in shape. Paper chromatography was used to determine the radiochemical impurity of radioactive microspheres. Radionuclide purity was determined using a gamma spectrometry system and an ultra-low level liquid scintillation spectrometer. The P(+) ions implantation stage was eliminated by embedding phosphorus particles in the matrix of the glass microspheres. This paper shows that a high temperature is not required to produce yttrium phosphorus aluminum silicate microspheres. The result shows that the silicone oil spheroidization method is a very suitable way to produce yttrium phosphorus glass microspheres. The topographical analysis of microspheres shows that the Y, P, Si, and Al elements are distributed in the microspheres and the distribution of elements in the samples is homogenous.

  10. Mechanical Properties, Purifying Techniques and Processing Methods of Metal Yttrium

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The mechanical properties of metal yttrium such as strength, plasticity, hardness and elasticity were introduced. The purifying techniques of yttrium were discussed in detail. The processing methods for metal yttrium including extruding, forging, rolling, wiredrawing and welding were also introduced. Finally, the potential use of yttrium and its alloys were prospected.

  11. Oxidation behavior of nickel-chromium-aluminum-yttrium - Magnesium oxide and nickel-chromium-aluminum-yttrium - zirconate type of cermets

    Science.gov (United States)

    Zaplatynsky, I.

    1976-01-01

    The 1100 and 1200 C cyclic oxidation resistance of dense Ni-Cr-Al-Y - MgO, Ni-Cr-Al-Y - CaZrO3, Ni-Cr-Al-Y - SrZrO3, Ni-Cr-Al-Y - MgZro3 cermets and a 70 percent dense Ni-Cr-Al-Y developmental material was determined. The cermets contained 60 and 50 volume percent of Ni-Cr-Al-Y which formed a matrix with the oxide particles imbedded in it. The cermets containing MgO were superior to cermets based on zirconates and to the porous Ni-Cr-Al-Y material.

  12. The effect of yttrium and thorium on the oxidation behavior of Ni-Cr-Al alloys

    Science.gov (United States)

    Kumar, A.; Nasrallah, M.; Douglass, D. L.

    1974-01-01

    The effect of quaternary additions of 0.5% Y, 0.5 and 1.0% Th to a base alloy of Ni-10CR-5Al on the oxidation behavior and mechanism was studied during oxidation in air over the range of 1000 to 1200 C. The presence of yttrium decreased the oxidation kinetics slightly, whereas, the addition of thorium caused a slight increase. Oxide scale adherence was markedly improved by the addition of the quaternary elements. Although a number of oxides formed on yttrium containing alloys, quantitative X-ray diffraction clearly showed that the rate-controlling step was the diffusion of aluminum through short circuit paths in a thin layer of alumina that formed parabolically with time. Although the scale adherence of the yttrium containing alloy was considerably better than the base alloys, spalling did occur that was attributed to the formation of the voluminous YAG particles which grew in a mushroom-like manner, lifting the protective scale off the subrate locally. The YAG particles formed primarily at grain boundaries in the substrate in which the yttrium originally existed as YNi9.

  13. Low-aluminum content iron-aluminum alloys

    Energy Technology Data Exchange (ETDEWEB)

    Sikka, V.K.; Goodwin, G.M.; Alexander, D.J. [and others

    1995-06-01

    The low-aluminum-content iron-aluminum program deals with the development of a Fe-Al alloy with aluminum content such as a produce the minimum environmental effect at room temperature. The FAPY is an Fe-16 at. % Al-based alloy developed at the Oak Ridge National Laboratory as the highest aluminum-containing alloy with essentially no environmental effect. The chemical composition for FAPY in weight percent is: aluminum = 8.46, chromium = 5.50, zirconium = 0.20, carbon = 0.03, molybdenum = 2.00, yttrium = 0.10 and iron = 83.71. The ignots of the alloy can be hot worked by extrusion, forging, and rolling processes. The hot-worked cast structure can be cold worked with intermediate anneals at 800{degrees}C. Typical room-temperature ductility of the fine-grained wrought structure is 20 to 25% for this alloy. In contrast to the wrought structure, the cast ductility at room temperature is approximately 1% with a transition temperature of approximately 100 to 150{degrees}C, above which ductility values exceed 20%. The alloy has been melted and processed into bar, sheet, and foil. The alloy has also been cast into slabs, step-blocks of varying thicknesses, and shapes. The purpose of this section is to describe the welding response of cast slabs of three different thicknesses of FAPY alloy. Tensile, creep, and Charpy-impact data of the welded plates are also presented.

  14. Interaction of oxygen vacancies in yttrium germanates

    KAUST Repository

    Wang, Hao

    2012-01-01

    Forming a good Ge/dielectric interface is important to improve the electron mobility of a Ge metal oxide semiconductor field-effect transistor. A thin yttrium germanate capping layer can improve the properties of the Ge/GeO 2 system. We employ electronic structure calculations to investigate the effect of oxygen vacancies in yttrium-doped GeO 2 and the yttrium germanates Y 2Ge 2O 7 and Y 2GeO 5. The calculated densities of states indicate that dangling bonds from oxygen vacancies introduce in-gap states, but the system remains insulating. However, yttrium-doped GeO 2 becomes metallic under oxygen deficiency. Y-doped GeO 2, Y 2Ge 2O 7 and Y 2GeO 5 are calculated to be oxygen substoichiometric under low Fermi energy conditions. The use of yttrium germanates is proposed as a way to effectively passivate the Ge/dielectric interface. This journal is © 2012 the Owner Societies.

  15. Lattice contraction in photochromic yttrium hydride

    Energy Technology Data Exchange (ETDEWEB)

    Maehlen, Jan Petter, E-mail: jepe@ife.no; Mongstad, Trygve T.; You, Chang Chuan; Karazhanov, Smagul

    2013-12-15

    Highlights: •Photochromic yttrium hydride films (YH:O) were prepared by reactive sputtering. •Black and transparent YH:O films were studied by time-resolved synchrotron XRD. •Both YH:O samples showed a lattice contraction upon illumination. •Also exposure to the X-ray beam itself results in a lattice contraction. -- Abstract: A strong photochromic effect was recently discovered in thin films of oxygen-containing yttrium hydride taking place at room temperature and reacting to ultraviolet and visible light. In this paper, we report on a lattice contraction upon illumination observed for thin-film samples of photochromic yttrium hydride, recorded by time-resolved X-ray diffraction using synchrotron radiation. The time dependence of the lattice contraction is consistent with the observed photochromic response of the samples.

  16. Yttrium doped BSCF membranes for oxygen separation

    DEFF Research Database (Denmark)

    Haworth, P.; Smart, S.; Glasscock, Julie;

    2011-01-01

    (x = 0.2) for iron resulted in a non-cubic crystal structure that did not exhibit oxygen permeation. The yttrium partial substitution in BSCFY discs (1.2 mm thick) delivered best results for x = 0.025, as oxygen fluxes reached 2.05 ml cm−2 min−1 at 900 °C, an increase of 160% as compared to a blank...... BSCF (x = 0) membrane. This was attributed to the combined effect of the formation of a greater number of oxygen vacancies, together with improved ion mobility, associated with the beneficial yttrium substitution into the BSCF perovskite structure which stemmed from the crystal lattice expansion....

  17. Magnetic structure of holmium-yttrium superlattices

    DEFF Research Database (Denmark)

    Jehan, D.A.; McMorrow, D.F.; Cowley, R.A.;

    1993-01-01

    that the superlattices have high crystallographic integrity: the structural coherence length parallel to the growth direction is typically almost-equal-to 2000 angstrom, while the interfaces between the two elements are well defined and extend over approximately four lattice planes. The magnetic structures were......We present the results of a study of the chemical and magnetic structures of a series of holmium-yttrium superlattices and a 5000 angstrom film of holmium, all grown by molecular-beam epitaxy. By combining the results of high-resolution x-ray diffraction with detailed modeling, we show...... determined using neutron-scattering techniques. The moments on the Ho3+ ions in the superlattices form a basal-plane helix. From an analysis of the superlattice structure factors of the primary magnetic satellites, we are able to determine separately the contributions made by the holmium and yttrium...

  18. Aluminum alloy

    Science.gov (United States)

    Blackburn, Linda B. (Inventor); Starke, Edgar A., Jr. (Inventor)

    1989-01-01

    This invention relates to aluminum alloys, particularly to aluminum-copper-lithium alloys containing at least about 0.1 percent by weight of indium as an essential component, which are suitable for applications in aircraft and aerospace vehicles. At least about 0.1 percent by weight of indium is added as an essential component to an alloy which precipitates a T1 phase (Al2CuLi). This addition enhances the nucleation of the precipitate T1 phase, producing a microstructure which provides excellent strength as indicated by Rockwell hardness values and confirmed by standard tensile tests.

  19. Thermal Spin Dynamics of Yttrium Iron Garnet

    Science.gov (United States)

    Barker, Joseph; Bauer, Gerrit E. W.

    2016-11-01

    The magnetic insulator yttrium iron garnet can be grown with near perfection and is therefore and ideal conduit for spin currents. It is a complex material with 20 magnetic moments in the unit cell. In spite of being a ferrimagnet, YIG is almost always modeled as a simple ferromagnet with a single spin wave mode. We use the method of atomistic spin dynamics to study the temperature evolution of the full spin wave spectrum, in quantitative agreement with neutron scattering experiments. The antiferromagnetic or optical mode is found to suppress the spin Seebeck effect at room temperature and beyond due to thermally pumped spin currents with opposite polarization to the ferromagnetic mode.

  20. Nonlinear FMR spectra in yttrium iron garnet

    Directory of Open Access Journals (Sweden)

    Yu.M. Bunkov, P.M. Vetoshko, I.G. Motygullin, T.R. Safin, M.S. Tagirov, N.A. Tukmakova

    2015-12-01

    Full Text Available Results of demagnetizing effect studies in yttrium iron garnet Y3Fe5O12 thin films are reported. Experiments were performed on X-Band of electron paramagnetic resonance spectrometer at room temperature. The ferromagnetic resonance (FMR spectra were obtained for one-layer single crystal YIG films for different values of the applied microwave power. Nonlinear FMR spectra transformation by the microwave power increasing in various directions of magnetic field sweep was observed. It is explained by the influence of the demagnetization action of nonequilibrium magnons.

  1. Unconventional Superfluidity in Yttrium Iron Garnet Films

    Science.gov (United States)

    Sun, Chen; Nattermann, Thomas; Pokrovsky, Valery L.

    2016-06-01

    We argue that the magnon condensate in yttrium iron garnet may display experimentally observable superfluidity at room temperature despite the 100 times dominance of the normal density over superfluid ones. The superfluidity has a more complicated nature than in known superfluids since the U(1) symmetry of the global phase shift is violated by the dipolar interaction leading to the exchange of spin moment between the condensate and the crystal lattice. It produces periodic inhomogeneity in the stationary superfluid flow. We discuss the manner of observation and possible applications of magnon superfluidity. It may strongly enhance the spin-torque effects and reduce the energy consumption of the magnonic devices.

  2. Ferroelectricity in yttrium-doped hafnium oxide

    OpenAIRE

    Müller, J.; Schröder, U; Böscke, T. S.; Müller, I.; U. Böttger; De Wilde, L; Sundqvist, J.; Lemberger, M.; Kücher, P.; Mikolajick, T; Frey, Lothar

    2012-01-01

    Structural and electrical evidence for a ferroelectric phase in yttrium doped hafnium oxide thin films is presented. A doping series ranging from 2.3 to 12.3 mol% YO1.5 in HfO2 was deposited by a thermal atomic layer deposition process. Grazing incidence X-ray diffraction of the 10 nm thick films revealed an orthorhombic phase close to the stability region of the cubic phase. The potential ferroelectricity of this orthorhombic phase was confirmed by polarization hysteresis measurements on tit...

  3. Morphology controllable synthesis of yttrium oxide-based phosphors from yttrium citrate precursors

    Institute of Scientific and Technical Information of China (English)

    HUANG Manlian; GUO Kai; MAN Zhenyong; CHEN Haohong; YANG Xinxin; XU Fangfang; ZHAO Jingtai

    2011-01-01

    A novel yttrium citrate-templated conversion method for morphology controlled synthesis ofY2O3 microspheres,microflowers and microsheets was reported for the first time.The precursors with controllable morphologies were synthesized with a homogenous precipitation method in aqueous solution without any surfactant.Y2O3 samples with well-preserved morphological architectures were obtained by a subsequent thermal transformation strategy.The chemical formula of the precursor was identified and a two-stage growth mechanism was proposed.The effects of the aging time,reaction temperature,reactant concentration and molar ratio of yttrium nitrate to sodium citrate were discussed.The photoluminescence properties of the Y2O3∶Eu3+ microspheres,microflowers and microsheets prepared were also studied.

  4. Ferroelectricity in yttrium-doped hafnium oxide

    Science.gov (United States)

    Müller, J.; Schröder, U.; Böscke, T. S.; Müller, I.; Böttger, U.; Wilde, L.; Sundqvist, J.; Lemberger, M.; Kücher, P.; Mikolajick, T.; Frey, L.

    2011-12-01

    Structural and electrical evidence for a ferroelectric phase in yttrium doped hafnium oxide thin films is presented. A doping series ranging from 2.3 to 12.3 mol% YO1.5 in HfO2 was deposited by a thermal atomic layer deposition process. Grazing incidence X-ray diffraction of the 10 nm thick films revealed an orthorhombic phase close to the stability region of the cubic phase. The potential ferroelectricity of this orthorhombic phase was confirmed by polarization hysteresis measurements on titanium nitride based metal-insulator-metal capacitors. For 5.2 mol% YO1.5 admixture the remanent polarization peaked at 24 μC/cm2 with a coercive field of about 1.2 MV/cm. Considering the availability of conformal deposition processes and CMOS-compatibility, ferroelectric Y:HfO2 implies high scaling potential for future, ferroelectric memories.

  5. Influences of Yttrium on Cyclic Oxidation Behavior of Fe-Cr-Al Alloy

    Institute of Scientific and Technical Information of China (English)

    辛丽; 李美栓; 钱余海; 李铁藩

    2001-01-01

    The 1100 ℃ cyclic oxidation behavior of Fe-23Cr-5Al alloy modified by yttrium was studied. Yttrium was added to this alloy in the form of (1) metallic addition, (2) yttrium oxide dispersion and (3) ion implantation. Cracking and spalling occurred on the convoluted scale formed on Y-free alloy and the substrate was exposed. A flat dense scale without spallation was formed on the yttrium alloying addition or yttrium oxide dispersion alloy. Spallation mainly occurred between two layers of the scale on the 1×1017Y ions/cm2-implanted alloy. The results indicate the main reason that the adhesion of alumina scale was improved by yttrium addition lies in that yttrium is liable to form a stable yttrium sulfide with sulfur in the alloy and prevent sulfur interface segregation. Another reason is that the growth mechanism of alumina scale was changed by yttrium addition.

  6. Neurobehavioral Assessment of Rats Exposed to Yttrium Nitrate during Development

    Institute of Scientific and Technical Information of China (English)

    LI Chen Xi; MA Chuan; FANG Hai Qin; ZHI Yuan; YU Zhou; XU Hai Bin; JIA Xu Dong

    2015-01-01

    Objective The aim of this study was to assess the effects of yttrium nitrate on neurobehavioral development in Sprague-Dawley rats. Methods Dams were orally exposed to 0, 5, 15, or 45 mg/kg daily of yttrium nitrate from gestation day (GD) 6 to postnatal day (PND) 21. Body weight and food consumption were monitored weekly. Neurobehavior was assessed by developmental landmarks and reflexes, motor activity, hot plate, Rota-rod and cognitive tests. Additionally, brain weights were measured on PND 21 and 70. Results No significant difference was noted among all groups for maternal body weight and food consumption. All yttrium-exposed offspring showed an increase in body weight on PND 21;however, no significant difference in body weight for exposed pups versus controls was observed 2 weeks or more after the yttrium solution was discontinued. The groups given 5 mg/kg daily decreased significantly in the duration of female forelime grip strength and ambulation on PND 13. There was no significant difference between yttrium-exposed offspring and controls with respect to other behavioral ontogeny parameters and postnatal behavioral test results. Conclusion Exposure of rats to yttrium nitrate in concentrations up to 45 mg/kg daily had no adverse effects on their neurobehavioral development.

  7. Influence of Yttrium and Ytterbium on Reaction Performance of Platinum-Rhenium Reforming Catalyst

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The influence of yttrium and ytterbium on the catalytic performance of Pt-Re reforming cata-lysts was studied in a continuous flow pressurized microreactor-chromatograph system and pilot unit. Theresults of micro-reactor test showed that both yttrium and ytterbium could improve the selectivity of Pt-Recatalysts for the conversion ofn-heptane as well as MCP into aromatics, but also suppressed their activityas well. Pilot test results showed that yttrium and ytterbium enhanced both the selectivity and activity ofPt-Re catalysts for naphtha reforming. Yttrium showed more improvement than ytterbium. The perfor-mance difference between microreactor test and pilot test might be due to the difference in improvement ofcatalytic stability of yttrium or ytterbium modified Pt-Re catalysts. Yttrium and ytterbium improved thecoking resistance of yttrium or ytterbium modified Pt-Re catalysts. TEM determination results indicatedthat both yttrium and ytterbium had improved the thermal stability of Pt-Re catalysts.

  8. Yttrium-90 microsphere induced gastrointestinal tract ulceration

    Directory of Open Access Journals (Sweden)

    Rikabi Ali A

    2008-09-01

    Full Text Available Abstract Background Radiomicrosphere therapy (RT utilizing yttrium-90 (90Y microspheres has been shown to be an effective regional treatment for primary and secondary hepatic malignancies. We sought to determine a large academic institution's experience regarding the extent and frequency of gastrointestinal complications. Methods Between 2004 and 2007, 27 patients underwent RT for primary or secondary hepatic malignancies. Charts were subsequently reviewed to determine the incidence and severity of GI ulceration. Results Three patients presented with gastrointestinal bleeding and underwent upper endoscopy. Review of the pretreatment angiograms showed normal vascular anatomy in one patient, sclerosed hepatic vasculature in a patient who had undergone prior chemoembolization in a second, and an aberrant left hepatic artery in a third. None had undergone prophylactic gastroduodenal artery embolization. Endoscopic findings included erythema, mucosal erosions, and large gastric ulcers. Microspheres were visible on endoscopic biopsy. In two patients, gastric ulcers were persistent at the time of repeat endoscopy 1–4 months later despite proton pump inhibitor therapy. One elderly patient who refused surgical intervention died from recurrent hemorrhage. Conclusion Gastrointestinal ulceration is a known yet rarely reported complication of 90Y microsphere embolization with potentially life-threatening consequences. Once diagnosed, refractory ulcers should be considered for aggressive surgical management.

  9. Mechanical properties of lanthanum and yttrium chromites

    Energy Technology Data Exchange (ETDEWEB)

    Paulik, S.W.; Armstrong, T.R. [Pacific Northwest National Lab., Richland, WA (United States)

    1996-12-31

    In an operating high-temperature (1000{degrees}C) solid oxide fuel cell (SOFC), the interconnect separates the fuel (P(O{sub 2}){approx}10{sup -16} atm) and the oxidant (P(O2){approx}10{sup 0.2} atm), while being electrically conductive and connecting the cells in series. Such severe atmospheric and thermal demands greatly reduce the number of viable candidate materials. Only two materials, acceptor substituted lanthanum chromite and yttrium chromite, meet these severe requirements. In acceptor substituted chromites (Sr{sup 2+} or Ca{sup 2+} for La{sup 3+}), charge compensation is primarily electronic in oxidizing conditions (through the formation of Cr{sup 4+}). Under reducing conditions, ionic charge compensation becomes significant as the lattice becomes oxygen deficient. The formation of oxygen vacancies is accompanied by the reduction of Cr{sup 4+} ions to Cr{sup 3+} and a resultant lattice expansion. The lattice expansion observed in large chemical potential gradients is not desirable and has been found to result in greatly reduced mechanical strength.

  10. Evidence of yttrium silicate inclusions in YSZ-porcelain veneers.

    Science.gov (United States)

    Stoner, Brian R; Griggs, Jason A; Neidigh, John; Piascik, Jeffrey R

    2014-04-01

    This report introduces the discovery of crystalline defects that can form in the porcelain veneering layer when in contact with yttria-stabilized zirconia (YSZ). The focus was on dental prostheses and understanding the defects that form in the YSZ/porcelain system; however the data reported herein may have broader implications toward the use and stability of YSZ-based ceramics in general. Specimens were cut from fully sintered YSZ plates and veneering porcelain was applied (porcelain veneer. Local EDAX (SEM) was performed in the regions of visible inclusions and showed significant increases in yttrium concentration. TEM specimens also showed apparent inclusions in the porcelain and selected area electron diffraction was performed on these regions and found the inclusions to be crystalline and identified as either yttrium-silicate (Y2 SiO5 ) or yttrium-disilicate (Y2 Si2 O7 ). Micro-CT data showed that yttrium-silicate precipitates were distributed throughout the thickness of the porcelain veneer. Future studies are needed to determine whether many of the premature failures associated with this materials system may be the result of crystalline flaws that form as a result of high temperature yttrium diffusion near the surfaces of YSZ.

  11. Enhancement of Superconductivity of Lanthanum and Yttrium Sesquicarbide

    Science.gov (United States)

    Krupka, M. C.; Giorgi, A. L.; Krikorian, N. H.; Szklarz, E. G.

    1972-06-22

    A method of enhancing the superconductivity of body-centered cubic lanthanum and yttrium sesquicarbide through formation of the sesquicarbides from ternary alloys of novel composition (N/sub x/M/sub 1-x/)C/sub z/, where N is yttrium or lanthanum, M is thorium, any of the Group IV and VI transition metals, or gold, germanium or silicon, and z is approximately 1.2 to 1.6. These ternary sesquicarbides have superconducting transition temperatures as high as 17.0/sup 0/K.

  12. Interfacial Behavior of Sulfur and Yttrium in Yttrium Modified Ni3Al-Based Alloy IC6 during High Temperature Oxidation Process

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The interfacial behavior of sulfur and yttrium in the yttrium-modified Ni3Al-based alloy IC6 during oxidation at 1100 ℃ was analyzed by X-ray line scan of electron probe microstructural analysis(EPMA). The results show that the migration and segregation of sulfur to the interface between oxide scale and the substrate at high temperature is retarded owing to the presence of yttrium. This is attributed to the desulfurization by yttrium in the melt and the trapping of sulfur by yttrium rich phases during oxidation, which leads to improving the coherence between oxide scale and substrate. Another reason of increasing the high temperature oxidation resistance of alloy IC6 by the addition of yttrium is that yttrium migrates to the grain boundaries of oxides during oxidation and hence improve their strength. This results in the transformation of the oxide scale spallation cracks from intergranular cracks for alloy without yttrium to transgranular ones for yttrium-modified alloy.

  13. Hereditary haemorrhagic telangiectasia treated by pulsed neodymium:yttrium-aluminium-garnet (Nd:YAG) laser (1,064 nm).

    Science.gov (United States)

    Werner, A; Bäumler, W; Zietz, S; Kühnel, T; Hohenleutner, U; Landthaler, M

    2008-10-01

    Hereditary haemorrhagic telangiectasia (HHT) is a familial, autosomal, dominant, multi-system, vascular, dysplasia. Besides repetitive epistaxis, cutaneous eruptive macules and nodules lead to recurring bleeding and cosmetic problems. We report on a pilot study of four cases of HHT in which cutaneous lesions were treated with a pulsed neodymium:yttrium-aluminum-garnet (Nd:YAG) laser (1,064 nm). Pulsed Nd:YAG laser treatment, without anaesthesia, was performed several times on eruptive angiomas on palmar and facial skin. Lesions on fingers and face mostly showed very good, or even complete, clearing after the first laser treatment. Several macules required multiple treatment; only a few lesions showed no effect. Pulsed Nd:YAG laser therapy (1,064 nm) appears to be an effective and safe treatment option for hereditary haemorrhagic telangiectasia on the skin of face and extremities.

  14. Thermal decomposition of Yttrium(III) isovalerate in argon

    DEFF Research Database (Denmark)

    Grivel, Jean-Claude; Yue, Zhao; Tang, Xiao;

    2016-01-01

    The thermal behaviour of yttrium(III) isovalerate (Y(C4H9CO2)3) was studied in argon by means of thermogravimetry, differential thermal analysis, FTIR-spectroscopy, hot-stage optical microscopy and X-ray diffraction with a laboratory Cu-tube source as well as with a synchrotron radiation source...

  15. Thermal decomposition of yttrium(III) valerate in argon

    DEFF Research Database (Denmark)

    Grivel, Jean-Claude; Yue, Zhao; Tang, Xiao;

    2014-01-01

    The thermal decomposition of yttrium(III) valerate (Y(C4H9CO2)3) was studied in argon by means of thermogravimetry, differential thermal analysis, IR-spectroscopy, X-ray diffraction, in-situ synchrotron diffraction and hot-stage microscopy as well as room temperature optical microscopy. Melting...

  16. High performance yttrium-doped BSCF hollow fibre membranes

    DEFF Research Database (Denmark)

    Haworth, P.; Smart, S.; Glasscock, Julie;

    2012-01-01

    Oxygen production from BSCF (Ba0.5Sr0.5Co0.8Fe0.2O3−δ) and yttrium-doped BSCF (Ba0.5Sr0.5Co0.8Fe0.175Y0.025O3−δ) hollow fibres was investigated, and the role of yttrium in the crystal structure was further explored using high-temperature X-ray diffraction. Yttrium substitution acted to increase...... the oxygen flux significantly, from 4.9 to 7.0mlcm−2min−1 at 900°C for the BSCF and the BSCFY membranes, respectively. Permeation was particularly enhanced at lower temperatures, between 66% and 92% over the range 650–800°C. The lattice expansion determined from high temperature X-ray diffraction.......3mm) hollow fibres operating below the critical length (i.e. limited surface kinetics regime) indicates that yttrium has enhanced the surface exchange rates. XRD patterns showed split peaks around 2θ 31° and 56° above 200°C, likely corresponding to a coexisting hexagonal perovskite phase. This peak...

  17. ALUMINUM BOX BUNDLING PRESS

    Directory of Open Access Journals (Sweden)

    Iosif DUMITRESCU

    2015-05-01

    Full Text Available In municipal solid waste, aluminum is the main nonferrous metal, approximately 80- 85% of the total nonferrous metals. The income per ton gained from aluminum recuperation is 20 times higher than from glass, steel boxes or paper recuperation. The object of this paper is the design of a 300 kN press for aluminum box bundling.

  18. Application of Stereology on Neodymium-Doped Yttrium Aluminum Garnet (Nd: YAG) Transparent Ceramics

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Nd: YAG precursor powders were synthesized by homogeneous precipitation, and Nd: YAG transparent ceramics were prepared by vacuum sintering at 1700 ℃ for 5 h. The ceramic materials were characterized by light transmittance and field emission gun-environment scanning microscope. Using statistics and stereology theory, study was carried out on the quantitative relationships between light transmittance and stereological parameters in three-dimensional Euclidean space. It is found that the transmittance of Nd:YAG with 1 mm in thickness is about 45% and 58% in visible and near-infrared wavelength, respectively. The transmittance linearly increases with increasing equivalent sphere diameter and reaches the theoretical value of single crystal when the equivalent sphere diameter is 20μm. The transmittance decreases with the increasing of mean specific area per unit volume of grain and discrete grains, and the transmittance decreases with increasing mean free distance of grains in Nd:YAG ceramics.

  19. Repair of Damaged M-Chromium-Aluminum-Yttrium Coatings Targeting Petroleum Industry Applications

    Science.gov (United States)

    Farhat, Rabab

    The increase in efficiency of furnace and refinery components in petroleum industries has been the target of many studies. However, the repair technology for damaged pieces is still to be developed. During prolonged service, a degradation of developed coatings occurs as a result of the harsh environment. Therefore, a repair technology, which can extend the life of the coatings, is now under consideration. In this work, electrospark deposition (ESD) has been investigated to understand the solidification behavior and its possibility to repair damaged MCrAlY coatings. Ni-based alloys with different compositions were deposited on Ni substrate using ESD to understand crystal structure of the solidified deposit and the effect of the dissimilar weld composition on dilution. The electrode samples were prepared by spark plasma sintering (SPS). Firstly, different coatings with single and bi-phase microstructure were deposited on pure Ni substrate. Secondly, NiCoCrAlY and CoNiCrAlY were deposited on the damaged spot of the oxidized NiCoCrAlY and CoNiCrAlY respectively. A fine microstructure of metastable phases obtained from each deposit. Also, it was found that an epitaxial growth of NiCoCrAlY and CoNiCrAlY were obtained on the damaged spots. In addition, α-Al 2O3 was obtained on the surface of the deposit after 24hr oxidation at 1000°C.

  20. Processing and Characterization of Polycrystalline Yag (Yttrium Aluminum Garnet) Core-Clad Fibers - Postprint

    Science.gov (United States)

    2015-01-01

    Nicholas Usechak, Hyun Jun Kim, Santeri Potticary, and Matthew O’Malley Optoelectronics Technology Branch Aerospace Components & Subsystems Division... Aerospace Components & Subsystems Division Air Force Research Laboratory, Sensors Directorate Wright-Patterson Air Force Base, OH 45433-7320 Air Force...clad fiber, ceramic processing 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT: SAR 8. NUMBER OF PAGES 10 19a. NAME OF

  1. Percutaneous yttrium aluminum garnet-laser lithotripsy of intrahepatic stones and casts after liver transplantation

    DEFF Research Database (Denmark)

    Schlesinger, Nis Hallundbaek; Svenningsen, Peter; Frevert, Susanne;

    2015-01-01

    % needed additional interventions in the form of percutaneous transhepatic cholangiography and dilation (17%), re-PTCSL (11%), self-expandable metallic stents (22%), or hepaticojejunostomy (6%); and 22% eventually underwent retransplantation. The overall liver graft survival rate was 78%. Two patients died......Bile duct stones and casts (BDSs) contribute importantly to morbidity after liver transplantation (LT). The purpose of this study was to estimate the clinical efficacy, safety, and long-term results of percutaneous transhepatic cholangioscopic lithotripsy (PTCSL) in transplant recipients......, prevented graft failure in 78% of the cases....

  2. Aluminum-Free Semiconductors and Packaging

    Energy Technology Data Exchange (ETDEWEB)

    Emanuel, M.A.

    2000-02-03

    The use of laser diodes instead of flashlamps to pump solid state lasers generally results in lighter weight, more compact systems with improved efficiency and reliability. These traits are important to a wide variety of applications in military, industrial and other areas. Common solid state laser systems such as yttrium aluminum garnet doped with neodymium or ytterbium (Nd:YAG and Yb:YAG, respectively) require pump light in the 800 to 1000 nm range, and such laser diodes have typically been fabricated in the AlGaAs material system on a GaAs substrate. Unfortunately, the presence of aluminum in or near the light-generating regions of these devices appears to limit their high-power performance, so for improved performance attention has turned to the aluminum-free (''Al-free'') material system of InGaAsP on a GaAs substrate. Laser diodes in this system offer the wavelength coverage similar to the AlGaAs/GaAs material system, and early results suggest that they may offer improved high-power performance. However, such Al-free diodes are more challenging to manufacture than AlGaAs-based devices. The goal of this LDRD project has been to evaluate Al-free diode technology in comparison with conventional AlGaAs-based structures for use in diode-pumped solid state lasers. This has been done by testing commercially available devices, surveying the literature, developing in-house capability in order to explore new device designs, and by engaging a leading university research group in the field.

  3. Yttrium-90 DOTATOC: first clinical results

    Energy Technology Data Exchange (ETDEWEB)

    Otte, A. [Basel Univ. (Switzerland). Nuklearmedizinische Abt.; Herrmann, R. [University Hospital, School of Medicine, Basel (Switzerland). Dept. of Oncology; Heppeler, A.; Behe, M.; Jermann, E.; Powell, P.; Maecke, H.R.; Muller, J. [University Hospital, School of Medicine, Basel (Switzerland). Inst. of Radiochemistry

    1999-11-01

    In a pilot study, DOTA-d-Phe{sup 1}-Tyr{sup 3}-octreotide (DOTATOC), which can be labelled with the {beta}-emitting radioisotope yttrium-90, has recently been used for the treatment of patients with advanced somatostatin receptor-positive tumours who had no other treatment option. The aim of the present study was to elucidate the therapeutic potential of {sup 90}Y-DOTATOC in a larger number of patients employing a standardized treatment protocol. Careful attention was paid to any side-effects (renal and/or haematological toxicity). Of 44 patients with advanced somatostatin receptor-positive tumours of different histology, 29 could be included in the study. The 15 patients who were excluded from the study protocol were assigned to our institution for purely compassionate reasons. The 29 patients who were included received four or more single doses of {sup 90}Y-DOTATOC with ascending activity at intervals of approximately 6 weeks (cumulative dose 6120{+-}1347 MBq/m{sup 2}) with the aim of performing an intra-patient dose escalation study. In total, 127 single treatments were given. In eight of these 127 single treatments, total doses of {>=}3700 MBq were administered. In an effort to prevent renal toxicity, two patients received Hartmann-Hepa 8% solution during all therapy cycles, while 13 patients did so during some but not all therapy cycles; in 14 patients no solution was administered during the therapy cycles. The treatment was monitored by computed tomography and indium-111 DOTATOC scintigraphy. Blood parameters were controlled weekly, while tumour markers and liver enzymes were controlled 6-weekly. Of the 29 patients, 24 patients showed no severe renal or haematological toxicity (toxicity {<=} grade 2 according to the National Cancer Institute grading criteria). These 24 patients received a cumulative dose of {<=}7400 MBq/m{sup 2}. Five patients developed renal and/or haematological toxicity. All of these five patients received a cumulative dose of >7400 MBq

  4. Yttrium aluminium garnet under pressure: Structural, elastic, and vibrational properties from ab initio studies

    Energy Technology Data Exchange (ETDEWEB)

    Monteseguro, V. [Departamento de Física and MALTA Consolider Team, Universidad de La Laguna, 38200 San Cristóbal de La Laguna, Santa Cruz de Tenerife (Spain); Rodríguez-Hernández, P.; Muñoz, A., E-mail: amunoz@ull.es [Departamento de Física and MALTA Consolider Team, Universidad de La Laguna, 38200 San Cristóbal de La Laguna, Santa Cruz de Tenerife (Spain); Instituto de Materiales y Nanotecnología. Universidad de La Laguna, 38200 San Cristóbal de La Laguna, Santa Cruz de Tenerife (Spain)

    2015-12-28

    The structural, elastic, and vibrational properties of yttrium aluminum garnet Y{sub 3}Al{sub 5}O{sub 12} are studied under high pressure by ab initio calculations in the framework of the density functional theory. The calculated ground state properties are in good agreement with the available experimental data. Pressure dependences of bond length and bulk moduli of the constituent polyhedra are reported. The evolution of the elastic constants and the major elastic properties, Young and shear modulus, Poisson's ratios, and Zener anisotropy ratio, are described. The mechanical stability is analyzed, on the light of “Born generalized stability criteria,” showing that the garnet is mechanically unstable above 116 GPa. Symmetries, frequencies, and pressure coefficients of the Raman-active modes are discussed on the basis of the calculated total and partial phonon density of states, which reflect the dynamical contribution of each atom. The relations between the phonon modes of Y{sub 3}Al{sub 5}O{sub 12} and the internal and external molecular modes of the different polyhedra are discussed. Infrared-active modes, as well as the silent modes, and their pressure dependence are also investigated. No dynamical instabilities were found below 116 GPa.

  5. Fabrication of independent nickel microstructures with anodizing of aluminum,laser irradiation, and electrodeposition

    Institute of Scientific and Technical Information of China (English)

    T. Kikuchi; M. Sakairi; H. Takahashi

    2003-01-01

    Independent microstructures made of Ni metal were fabricated by five sequential processes: porous anodic oxide film for-mation, pore sealing, laser irradiation, Ni electroplating, and removal of the aluminum substrate and anodic oxide films. Aluminumplates and rods were anodized in an oxalic acid solution to form porous type anodic oxide films, and then immersed in boiling dis-tilled water for pore sealing. The anodized and pore-sealed specimens were irradiated with a pulsed neodymium-doped yttrium alu-minum garnet (Nd-YAG) laser beam in a Ni plating solution to remove anodic oxide film locally by rotating and moving up / downwith an XYZθ-stage. Nickel was deposited at the area where film had been removed by cathodic polarization in the solution beforeremoving the aluminum substrate and anodic oxide films in NaOH solutions. Cylindrical or plain network structures were fabricated successfully.

  6. Thermal decomposition of yttrium(III) propionate and butyrate

    DEFF Research Database (Denmark)

    Grivel, Jean-Claude

    2013-01-01

    The thermal decompositions of yttrium(III) propionate monohydrate (Y(C2H5CO2)3·H2O) and yttrium(III) butyrate dihydrate (Y(C3H7CO2)3·2H2O) were studied in argon by means of thermogravimetry, differential thermal analysis, IR-spectroscopy, X-ray diffraction and hot-stage microscopy. These two...... of CO2 and a symmetrical ketone consisting of 3-pentanone and 4-heptanone respectively. Final conversion to Y2O3 takes pace with release of CO2. Elemental carbon that is left as a by-product is finally slowly burned by the residual oxygen present in the Ar atmosphere. Fusion is observed at ≈110°C...

  7. Hydrocarbon cracking with yttrium exchanged zeolite y catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Lochow, C.F.; Kovacs, D.B.

    1987-05-12

    A process is described for cracking a gas oil boiling range hydrocarbon feedstock comprising the step of contacting the feedstock in a catalytic cracking zone under catalytic cracking conditions to produce convulsion products comprising gasoline with a catalyst composition. The process comprises: a Y crystalline aluminosilicate zeolite, having the structure of faujasite and having uniform pore diameters and a silica to alumina mole ratio of at least about 5; an inorganic oxide matrix; and the zeolite having been ion exchanged with a mixture of rare earths prior to compositing with the matrix; and the zeolite having been subsequently further ion exchanged with yttrium following compositing with the matrix, whereby the catalyst composition contains 0.30 to 3.0 wt% yttrium.

  8. Determination of Trace Amount of Yttrium with Bromopyrogallol Red by Solid-phase Spectrophotometry

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A simple and sensitive method for the determination of trace amount of yttrium by solid-phase spectrophotometry has been studied. Yttrium can form a 1∶1 complex with bromopyrogallol red (BPR) on resin, which was determined directly at 605 nm, pH=6.5. It has a highly sensitivity ( = 6.3€?06) which is 300-fold higher than the corresponding spectrophotometry in solution. The method was applied to the determination of yttrium in churchite.

  9. Aspects of aluminum toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Hewitt, C.D.; Savory, J.; Wills, M.R. (Univ. of Virginia Health Sciences Center, Charlottesville (USA))

    1990-06-01

    Aluminum is the most abundant metal in the earth's crust. The widespread occurrence of aluminum, both in the environment and in foodstuffs, makes it virtually impossible for man to avoid exposure to this metal ion. Attention was first drawn to the potential role of aluminum as a toxic metal over 50 years ago, but was dismissed as a toxic agent as recently as 15 years ago. The accumulation of aluminum, in some patients with chronic renal failure, is associated with the development of toxic phenomena; dialysis encephalopathy, osteomalacic dialysis osteodystrophy, and an anemia. Aluminum accumulation also occurs in patients who are not on dialysis, predominantly infants and children with immature or impaired renal function. Aluminum has also been implicated as a toxic agent in the etiology of Alzheimer's disease, Guamiam amyotrophic lateral sclerosis, and parkinsonism-dementia. 119 references.

  10. Collectivity of the neutron-deficient odd yttrium isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Bucurescu, D.; Cata, G.; Ivascu, M.; Zamfir, N.V.; Liang, C.F.; Paris, P.

    1988-08-01

    Multishell IBFM-1 calculations are reported for the neutron-deficient odd yttrium isotopes (79-85), which give a good description of both the positive and negative parity levels known experimentally. An exchange force whose intensity varies with the mass number is required. This phenomenological variation reflects qualitatively the microscopic origin of the exchange term, and also points to possible systematics of the model parameters in the ALPHA approx. = 80 region of the Nsub(p)Nsub(n) type.

  11. Acromegaly with sleep disturbances relieved by yttrium-90 pituitary implantation

    Energy Technology Data Exchange (ETDEWEB)

    Rosenstock, J.; Doyle, F.H.; Joplin, G.F.; Jung, R.T.; Mashiter, K. (Hammersmith Hospital, London (UK). Postgraduate Medical School)

    1982-03-01

    A brief case history is presented of a patient, who, after yttrium-90 implantation, showed a complete clinical and hormonal remission of her acromegaly, maintaining normal pituitary function. The remarkable feature was the rapid disappearance of her attacks of somnolence within 96 hours of pituitary implantation, despite persistence of nocturnal snoring and well before any remodelling of soft tissues could have occurred. This response suggests that her daytime somnolence had a narcoleptic component.

  12. Aluminum powder metallurgy processing

    Energy Technology Data Exchange (ETDEWEB)

    Flumerfelt, J.F.

    1999-02-12

    The objective of this dissertation is to explore the hypothesis that there is a strong linkage between gas atomization processing conditions, as-atomized aluminum powder characteristics, and the consolidation methodology required to make components from aluminum powder. The hypothesis was tested with pure aluminum powders produced by commercial air atomization, commercial inert gas atomization, and gas atomization reaction synthesis (GARS). A comparison of the GARS aluminum powders with the commercial aluminum powders showed the former to exhibit superior powder characteristics. The powders were compared in terms of size and shape, bulk chemistry, surface oxide chemistry and structure, and oxide film thickness. Minimum explosive concentration measurements assessed the dependence of explosibility hazard on surface area, oxide film thickness, and gas atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization processing conditions. The GARS aluminum powders were exposed to different relative humidity levels, demonstrating the effect of atmospheric conditions on post-atomization oxidation of aluminum powder. An Al-Ti-Y GARS alloy exposed in ambient air at different temperatures revealed the effect of reactive alloy elements on post-atomization powder oxidation. The pure aluminum powders were consolidated by two different routes, a conventional consolidation process for fabricating aerospace components with aluminum powder and a proposed alternative. The consolidation procedures were compared by evaluating the consolidated microstructures and the corresponding mechanical properties. A low temperature solid state sintering experiment demonstrated that tap densified GARS aluminum powders can form sintering necks between contacting powder particles, unlike the total resistance to sintering of commercial air atomization aluminum powder.

  13. Influences of Yttrium on Adhesion of Oxide Scale of Fe-Cr-Al Alloy

    Institute of Scientific and Technical Information of China (English)

    辛丽; 李美栓; 周龙江; 王福会; 李铁藩

    2001-01-01

    The 1100 ℃ isothermal oxidation behavior of Fe-23Cr-5Al alloy modified by yttrium addition was studied by means of thermogravimetric analysis, scanning electron microscopy and energy dispersive X-ray analysis. Yttrium was added to this alloy in the forms of metallic addition, yttrium oxide and ion implant. Cracking and spalling occurred on the convoluted scale formed on Y-free alloy and exposed the substrate. A flat dense scale without spallation was formed on the yttrium alloying addition or yttrium oxide dispersion alloy. The scale adhesion was also improved by 1×1017Y+/cm2-implantation. The results indicate the convoluted morphology of the scale on Fe-23Cr-5Al-0.21Ti alloy is related to the growth mechanism of the alumina scale, and the spallation of the scale is related to sulfur segregation at the scale/alloy interface. The main reason that the adhesion of alumina scale is improved by yttrium addition lies in the following. Yttrium is liable to form a stable yttrium sulfide with sulfur in the alloy and prevent sulfur interface from segregation. Another reason is that the growth mechanism of alumina scale is changed by yttrium addition.

  14. Is the Aluminum Hypothesis Dead?

    OpenAIRE

    Lidsky, Theodore I.

    2014-01-01

    The Aluminum Hypothesis, the idea that aluminum exposure is involved in the etiology of Alzheimer disease, dates back to a 1965 demonstration that aluminum causes neurofibrillary tangles in the brains of rabbits. Initially the focus of intensive research, the Aluminum Hypothesis has gradually been abandoned by most researchers. Yet, despite this current indifference, the Aluminum Hypothesis continues to attract the attention of a small group of scientists and aluminum continues to be viewed w...

  15. High energy density aluminum battery

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Gilbert M.; Paranthaman, Mariappan Parans; Dai, Sheng; Dudney, Nancy J.; Manthiram, Arumugan; McIntyre, Timothy J.; Sun, Xiao-Guang; Liu, Hansan

    2016-10-11

    Compositions and methods of making are provided for a high energy density aluminum battery. The battery comprises an anode comprising aluminum metal. The battery further comprises a cathode comprising a material capable of intercalating aluminum or lithium ions during a discharge cycle and deintercalating the aluminum or lithium ions during a charge cycle. The battery further comprises an electrolyte capable of supporting reversible deposition and stripping of aluminum at the anode, and reversible intercalation and deintercalation of aluminum or lithium at the cathode.

  16. Is the Aluminum Hypothesis dead?

    Science.gov (United States)

    Lidsky, Theodore I

    2014-05-01

    The Aluminum Hypothesis, the idea that aluminum exposure is involved in the etiology of Alzheimer disease, dates back to a 1965 demonstration that aluminum causes neurofibrillary tangles in the brains of rabbits. Initially the focus of intensive research, the Aluminum Hypothesis has gradually been abandoned by most researchers. Yet, despite this current indifference, the Aluminum Hypothesis continues to attract the attention of a small group of scientists and aluminum continues to be viewed with concern by some of the public. This review article discusses reasons that mainstream science has largely abandoned the Aluminum Hypothesis and explores a possible reason for some in the general public continuing to view aluminum with mistrust.

  17. Anodizing Aluminum with Frills.

    Science.gov (United States)

    Doeltz, Anne E.; And Others

    1983-01-01

    "Anodizing Aluminum" (previously reported in this journal) describes a vivid/relevant laboratory experience for general chemistry students explaining the anodizing of aluminum in sulfuric acid and constrasting it to electroplating. Additions to this procedure and the experiment in which they are used are discussed. Reactions involved are…

  18. The aluminum smelting process.

    Science.gov (United States)

    Kvande, Halvor

    2014-05-01

    This introduction to the industrial primary aluminum production process presents a short description of the electrolytic reduction technology, the history of aluminum, and the importance of this metal and its production process to modern society. Aluminum's special qualities have enabled advances in technologies coupled with energy and cost savings. Aircraft capabilities have been greatly enhanced, and increases in size and capacity are made possible by advances in aluminum technology. The metal's flexibility for shaping and extruding has led to architectural advances in energy-saving building construction. The high strength-to-weight ratio has meant a substantial reduction in energy consumption for trucks and other vehicles. The aluminum industry is therefore a pivotal one for ecological sustainability and strategic for technological development.

  19. Fluorescent lighting with aluminum nitride phosphors

    Energy Technology Data Exchange (ETDEWEB)

    Cherepy, Nerine J.; Payne, Stephen A.; Seeley, Zachary M.; Srivastava, Alok M.

    2016-05-10

    A fluorescent lamp includes a glass envelope; at least two electrodes connected to the glass envelope; mercury vapor and an inert gas within the glass envelope; and a phosphor within the glass envelope, wherein the phosphor blend includes aluminum nitride. The phosphor may be a wurtzite (hexagonal) crystalline structure Al.sub.(1-x)M.sub.xN phosphor, where M may be drawn from beryllium, magnesium, calcium, strontium, barium, zinc, scandium, yttrium, lanthanum, cerium, praseodymium, europium, gadolinium, terbium, ytterbium, bismuth, manganese, silicon, germanium, tin, boron, or gallium is synthesized to include dopants to control its luminescence under ultraviolet excitation. The disclosed Al.sub.(1-x)M.sub.xN:Mn phosphor provides bright orange-red emission, comparable in efficiency and spectrum to that of the standard orange-red phosphor used in fluorescent lighting, Y.sub.2O.sub.3:Eu. Furthermore, it offers excellent lumen maintenance in a fluorescent lamp, and does not utilize "critical rare earths," minimizing sensitivity to fluctuating market prices for the rare earth elements.

  20. Effect of Yttrium on High Temperature Oxidation Resistance of a Directionally Solidified Superalloy

    Institute of Scientific and Technical Information of China (English)

    宋立国; 李树索; 郑运荣; 韩雅芳

    2004-01-01

    The effect of rare earth element yttrium on the high temperature oxidation resistance of a directionally solidified Ni-base superalloy was studied with scanning electron microscopy(SEM), energy dispersive spectrum(EDS)and X-ray diffraction(XRD)techniques. The results show that the oxidation resistance of the alloy is substantially improved by adding proper amount of yttrium.

  1. Infrared spectra of oxygen-rich yttrium and lanthanum dioxygen/ozonide complexes in solid argon.

    Science.gov (United States)

    Gong, Yu; Ding, Chuanfan; Zhou, Mingfei

    2009-07-30

    The reactions of yttrium and lanthanum atoms with O(2) have been reinvestigated using matrix isolation infrared spectroscopy and theoretical calculations. The ground-state yttrium and lanthanum atoms react with O(2) to produce the inserted yttrium and lanthanum dioxide molecules as the initial products. The yttrium dioxide molecule interacts spontaneously with additional O(2) molecules to form the oxygen-rich OY(eta(2)-O(3)) complex and possibly the (eta(2)-O(2))Y(eta(2)-O(3))(2) complexes upon sample annealing, which can be regarded as the side-on bonded yttrium monoxide ozonide complex and the superoxo yttrium bisozonide complex, respectively. Visible irradiation induces the isomerization of the OY(eta(2)-O(3)) complex to the superoxo yttrium peroxide Y(eta(2)-O(2))(2) isomer, in which both the superoxo and peroxo ligands are side-on bonded to the yttrium center. The lanthanum dioxide molecule reacts with additional O(2) molecules to form the lanthanum dioxide-dioxygen complex with planar C(2v) symmetry, which rearranges to the lanthanum monoxide ozonide complex, OLa(eta(2)-O(3)), under near-infrared excitation.

  2. 40 CFR 721.10177 - Phosphoric acid, yttrium(3+) salt (1:1).

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Phosphoric acid, yttrium(3+) salt (1:1... Specific Chemical Substances § 721.10177 Phosphoric acid, yttrium(3+) salt (1:1). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as...

  3. Crystal field and magnetism with Wannier functions:rare-earth doped aluminum garnets

    Institute of Scientific and Technical Information of China (English)

    Eva Mihóková; Pavel Novák; Valentin V. Laguta

    2015-01-01

    Using the recently developed method we calculated the crystal field parameters in yttrium and lutetium aluminum garnets doped with seven trivalent Kramers rare-earth ions. We then inserted calculated parameters into the atomic-like Hamiltonian taking into account the electron-electron, spin-orbit and Zeeman interactions and determined the multiplet splitting by the crystal field as well as magneticĝ tensors. We compared calculated results with available experimental data. Very good agreement with the spectro-scopic data and qualitative agreement with experimentalĝ tensors was found.

  4. Clinical biochemistry of aluminum

    Energy Technology Data Exchange (ETDEWEB)

    King, S.W.; Savory, J.; Wills, M.R.

    1981-05-01

    Aluminum toxicity has been implicated in the pathogenesis of a number of clinical disorders in patients with chronic renal failure on long-term intermittent hemodialysis treatment. The predominant disorders have been those involving either bone (osteomalacic dialysis osteodystrophy) or brain (dialysis encephalopathy). In nonuremic patients, an increased brain aluminum concentration has been implicated as a neurotoxic agent in the pathogenesis of Alzheimer's disease and was associated with experimental neurofibrillary degeneration in animals. The brain aluminum concentrations of patients dying with the syndrome of dialysis encephalopathy (dialysis dementia) are significantly higher than in dialyzed patients without the syndrome and in nondialyzed patients. Two potential sources for the increased tissue content of aluminum in patients on hemodialysis have been proposed: (1) intestinal absorption from aluminum containing phosphate-binding gels, and (2) transfer across the dialysis membrane from aluminum in the water used to prepare the dialysate. These findings, coupled with our everyday exposure to the ubiquitous occurrence of aluminum in nature, have created concerns over the potential toxicity of this metal.

  5. Advances in aluminum pretreatment

    Energy Technology Data Exchange (ETDEWEB)

    Sudour, Michel; Maintier, Philippe [PPG Industries France, 3 Z.A.E. Les Dix Muids, B.P. 89, F-59583 Marly (France); Simpson, Mark [PPG Industries Inc., 1200 Piedmont Troy, Michigan 48083 (United States); Quaglia, Paolo [PPG Industries Italia, Via Garavelli 21, I-15028 Quattordio (Italy)

    2004-07-01

    As automotive manufacturers continue to look for ways to reduce vehicle weight, aluminum is finding more utility as a body panel component. The substitution of cold-rolled steel and zinc-coated substrates with aluminum has led to new challenges in vehicle pretreatment. As a result, changes to traditional pretreatment chemistries and operating practices are necessary in order to produce an acceptable coating on aluminum body panels. These changes result in increased sludging and other undesirable characteristics. In addition to the chemistry changes, there are also process-related problems to consider. Many existing automotive pretreatment lines simply were not designed to handle aluminum and its increased demands on filtration and circulation equipment. To retrofit such a system is capital intensive and in addition to requiring a significant amount of downtime, may not be totally effective. Thus, the complexities of pre-treating aluminum body panels have actually had a negative effect on efforts to introduce more aluminum into new vehicle design programs. Recent research into ways of reducing the negative effects has led to a new understanding of the nature of zinc phosphate bath -aluminum interactions. Many of the issues associated with the pretreatment of aluminum have been identified and can be mitigated with only minor changes to the zinc phosphate bath chemistry. The use of low levels of soluble Fe ions, together with free fluoride, has been shown to dramatically improve the efficiency of a zinc phosphate system processing aluminum. Appearance of zinc phosphate coatings, coating weights and sludge are all benefited by this chemistry change. (authors)

  6. Treatment of exhaust fluorescent lamps to recover yttrium: experimental and process analyses.

    Science.gov (United States)

    De Michelis, Ida; Ferella, Francesco; Varelli, Ennio Fioravante; Vegliò, Francesco

    2011-12-01

    The paper deals with recovery of yttrium from fluorescent powder coming from dismantling of spent fluorescent tubes. Metals are leached by using different acids (nitric, hydrochloric and sulphuric) and ammonia in different leaching tests. These tests show that ammonia is not suitable to recover yttrium, whereas HNO(3) produces toxic vapours. A full factorial design is carried out with HCl and H(2)SO(4) to evaluate the influence of operating factors. HCl and H(2)SO(4) leaching systems give similar results in terms of yttrium extraction yield, but the last one allows to reduce calcium extraction with subsequent advantage during recovery of yttrium compounds in the downstream. The greatest extraction of yttrium is obtained by 20% w/v S/L ratio, 4N H(2)SO(4) concentration and 90°C. Yttrium and calcium yields are nearly 85% and 5%, respectively. The analysis of variance shows that acid concentration alone and interaction between acid and pulp density have a significant positive effect on yttrium solubilization for both HCl and H(2)SO(4) medium. Two models are empirically developed to estimate yttrium and calcium concentration during leaching. Precipitation tests demonstrate that at least the stoichiometric amount of oxalic acid is necessary to recover yttrium efficiently and a pure yttrium oxalate n-hydrate can be produced (99% grade). The process is economically feasible if other components of the fluorescent lamps (glass, ferrous and non-ferrous scraps) are recovered after the equipment dismantling and valorized, besides the cost that is usually paid to recycling companies for collection, treatment or final disposal of such fluorescent powders.

  7. Spectroscopic properties of trivalent praseodymium in barium yttrium fluoride

    Energy Technology Data Exchange (ETDEWEB)

    Di Bartolo, B. E-mail: dibartob@bc.edurinodiba@attbi.com; Bowlby, B.E

    2003-05-01

    We have conducted a spectroscopic investigation of Pr{sup 3+} in barium yttrium fluoride (BaY{sub 2}O{sub 8}). Two doping concentrations were used: BaY{sub 2}F{sub 8}:Pr{sup 3+} (0.3%) and BaY{sub 2}F{sub 8}:Pr{sup 3+} (1%). The measurements included absorption, luminescence under continuous and pulsed excitations, and thermal effects on some sharp lines. The experimental results were used to characterize this system.

  8. Childhood acromegaly successfully treated with interstitial irradiation using Yttrium-90

    Energy Technology Data Exchange (ETDEWEB)

    Rosenstock, J.; Doyle, F.H.; Mashiter, K.; Joplin, G.F. (Royal Postgraduate Medical School, Hammersmith Hospital, London (UK). Dept. of Medicine and Radiology); Hall, R. (Royal Victoria Infirmary, Newcastle upon Tyne (UK))

    1982-01-01

    A child with a growth hormone producing tumour presented at the age of 4 1/2 years. The onset of the disease was at 18 months of age. Treatment was given with three doses of interstitial irradiation using Yttrium-90 implants. There were no local complications from the procedures. Now, 11 years after diagnosis, she is asymptomatic, of normal appearance, and her height and the size of the pituitary fossa are normal. Growth hormone levels are almost normal, thyroid function is intact, and she is maintained on prednisone and sex hormones.

  9. Corrosion Inhibitors for Aluminum.

    Science.gov (United States)

    Muller, Bodo

    1995-01-01

    Describes a simple and reliable test method used to investigate the corrosion-inhibiting effects of various chelating agents on aluminum pigments in aqueous alkaline media. The experiments that are presented require no complicated or expensive electronic equipment. (DDR)

  10. Advances in aluminum anodizing

    Science.gov (United States)

    Dale, K. H.

    1969-01-01

    White anodize is applied to aluminum alloy surfaces by specific surface preparation, anodizing, pigmentation, and sealing techniques. The development techniques resulted in alloys, which are used in space vehicles, with good reflectance values and excellent corrosive resistance.

  11. CORROSION PROTECTION OF ALUMINUM

    Science.gov (United States)

    Dalrymple, R.S.; Nelson, W.B.

    1963-07-01

    Treatment of aluminum-base metal surfaces in an autoclave with an aqueous chromic acid solution of 0.5 to 3% by weight and of pH below 2 for 20 to 50 hrs at 160 to 180 deg C produces an extremely corrosion-resistant aluminum oxidechromium film on the surface. A chromic acid concentration of 1 to 2% and a pH of about 1 are preferred. (D.C.W.)

  12. Theoretical investigation on homoleptic Yttrium tri-guanidinates

    Directory of Open Access Journals (Sweden)

    Salima Lakehal

    2014-12-01

    Full Text Available The electronic and molecular structures of the homoleptic Yttrium tris-guanidinates complexes Y[(NiPr2CNR1R2]3, [R1 = R2 = Me, Et and iPr] have been investigated employing DFT calculations in order to understand the structures, bonding and energies of the interactions between Yttrium metal and guanidinate ligands. The effect of the substitution on nitrogen position of guanidinate in these complexes has been also investigated employing DFT and TDDFT calculations for six kinds of models obtained by alternative substitution of alkyl on nitrogen of the guanidinate ligands. The results reveal that the substitution position plays a crucial role in the geometric structure by affecting the torsion angle and the HOMO–LUMO transitions. The energy decomposition analysis indicates a majority of ionic bonding in all systems; the exception is in the M4 (Y[(NYR2CNCR1R2]3; R = Et and R1 = R2 = H which present a significant degree of covalency.

  13. Yttrium oxide based three dimensional metamaterials for visible light cloaking

    Science.gov (United States)

    Rai, Pratyush; Kumar, Prashanth S.; Varadan, Vijay K.; Ruffin, Paul; Brantley, Christina; Edwards, Eugene

    2014-04-01

    Metamaterial with negative refractive index is the key phenomenon behind the concept of a cloaking device to hide an object from light in visible spectrum. Metamaterials made of two and three dimensional lattices of periodically placed electromagnetic resonant cells can achieve absorption and propagation of incident electromagnetic radiation as confined electromagnetic fields confined to a waveguide as surface plasmon polaritons, which can be used for shielding an object from in-tune electromagnetic radiation. The periodicity and dimensions of resonant cavity determine the frequency, which are very small as compared to the wavelength of incident light. Till now the phenomena have been demonstrated only for lights in near infrared spectrum. Recent advancements in fabrication techniques have made it possible to fabricate array of three dimensional nanostructures with cross-sections as small as 25 nm that are required for negative refractive index for wavelengths in visible light spectrum of 400-700 nm and for wider view angle. Two types of metamaterial designs, three dimensional concentric split ring and fishnet, are considered. Three dimensional structures consisted of metal-dielectric-metal stacks. The metal is silver and dielectric is yttrium oxide, other than conventional materials such as FR4 and Duroid. High κ dielectric and high refractive index as well as large crystal symmetry of Yttrium oxide has been investigated as encapsulating medium. Dependence of refractive index on wavelength and bandwidth of negative refractive index region are analyzed for application towards cloaking from light in visible spectrum.

  14. Recovery of yttrium from cathode ray tubes and lamps' fluorescent powders: experimental results and economic simulation.

    Science.gov (United States)

    Innocenzi, V; De Michelis, I; Ferella, F; Vegliò, F

    2013-11-01

    In this paper, yttrium recovery from fluorescent powder of lamps and cathode ray tubes (CRTs) is described. The process for treating these materials includes the following: (a) acid leaching, (b) purification of the leach liquors using sodium hydroxide and sodium sulfide, (c) precipitation of yttrium using oxalic acid, and (d) calcinations of oxalates for production of yttrium oxides. Experimental results have shown that process conditions necessary to purify the solutions and recover yttrium strongly depend on composition of the leach liquor, in other words, whether the powder comes from treatment of CRTs or lamp. In the optimal experimental conditions, the recoveries of yttrium oxide are about 95%, 55%, and 65% for CRT, lamps, and CRT/lamp mixture (called MIX) powders, respectively. The lower yields obtained during treatments of MIX and lamp powders are probably due to the co-precipitation of yttrium together with other metals contained in the lamps powder only. Yttrium loss can be reduced to minimum changing the experimental conditions with respect to the case of the CRT process. In any case, the purity of final products from CRT, lamps, and MIX is greater than 95%. Moreover, the possibility to treat simultaneously both CRT and lamp powders is very important and interesting from an industrial point of view since it could be possible to run a single plant treating fluorescent powder coming from two different electronic wastes.

  15. Recovery of yttrium from fluorescent powder of cathode ray tube, CRT: Zn removal by sulphide precipitation.

    Science.gov (United States)

    Innocenzi, Valentina; De Michelis, Ida; Ferella, Francesco; Beolchini, Francesca; Kopacek, Bernd; Vegliò, Francesco

    2013-11-01

    This work is focused on the recovery of yttrium and zinc from fluorescent powder of cathode ray tube (CRT). Metals are extracted by sulphuric acid in the presence of hydrogen peroxide. Leaching tests are carried out according to a 2(2) full factorial plan and the highest extraction yields for yttrium and zinc equal to 100% are observed under the following conditions: 3M of sulphuric acid, 10% v/v of H2O2 concentrated solution at 30% v/v, 10% w/w pulp density, 70°C and 3h of reaction. Two series of precipitation tests for zinc are carried out: a 2(2) full factorial design and a completely randomized factorial design. In these series the factors investigated are pH of solution during the precipitation and the amount of sodium sulphide added to precipitate zinc sulphide. The data of these tests are used to describe two empirical mathematical models for zinc and yttrium precipitation yields by regression analysis. The highest precipitation yields for zinc are obtained under the following conditions: pH equal to 2-2.5% and 10-12%v/v of Na2S concentrated solution at 10%w/v. In these conditions the coprecipitation of yttrium is of 15-20%. Finally further yttrium precipitation experiments by oxalic acid on the residual solutions, after removing of zinc, show that yttrium could be recovered and calcined to obtain the final product as yttrium oxide. The achieved results allow to propose a CRT recycling process based on leaching of fluorescent powder from cathode ray tube and recovery of yttrium oxide after removing of zinc by precipitation. The final recovery of yttrium is 75-80%.

  16. Aluminum, parathyroid hormone, and osteomalacia

    Energy Technology Data Exchange (ETDEWEB)

    Burnatowska-Hledin, M.A.; Kaiser, L.; Mayor, G.H.

    1983-01-01

    Aluminum exposure in man is unavoidable. The occurrence of dialysis dementia, vitamin D-resistant osteomalacia, and hypochromic microcytic anemia in dialysis patients underscores the potential for aluminum toxicity. Although exposure via dialysate and hyperalimentation leads to significant tissue aluminum accumulation, the ubiquitous occurrence of aluminum and the severe pathology associated with large aluminum burdens suggest that smaller exposures via the gastrointestinal tract and lungs could represent an important, though largely unrecognized, public health problem. It is clear that some aluminum absorption occurs with the ingestion of small amounts of aluminum in the diet and medicines, and even greater aluminum absorption is seen in individuals consuming large amounts of aluminum present in antacids. Aluminum absorption is enhanced in the presence of elevated circulating parathyroid hormone. In addition, elevated PTH leads to the preferential deposition of aluminum in brain and bone. Consequently, PTH is likely to be involved in the pathogenesis of toxicities in those organs. PTH excess also seems to lead to the deposition of aluminum in the parathyroid gland. The in vitro demonstration that aluminum inhibits parathyroid hormone release is consistent with the findings of a euparathyroid state in dialysis patients with aluminum related vitamin D-resistant osteomalacia. Nevertheless, it seems likely that hyperparathyroidism is at least initially involved in the pathogenesis of aluminum neurotoxicity and osteomalacia; the increases in tissue aluminum stores are followed by suppression of parathyroid hormone release, which is required for the evolution of osteomalacia. Impaired renal function is not a prerequisite for increased tissue aluminum burdens, nor for aluminum-related organ toxicity. Consequently, it is likely that these diseases will be observed in populations other than those with chronic renal disease.

  17. Transport of yttrium metal ions through fibers supported liquid membrane solvent extraction

    Institute of Scientific and Technical Information of China (English)

    A.G.Gaikwad; A.M.Rajput

    2010-01-01

    A novel idea of transport of yttrium(Ⅲ) metal ions through fibers supported liquid membrane in two stage processes namely source to membrane and membrane to receiving phase has been proposed.The fibers supported liquid membrane was impregnated with different concentrations carrier.The experimental variables explored were concentration of yttrium(Ⅲ) ions,pH of source phase,PC-88A concentration in membrane phase,acid concentration in receiving phase and stirring speed.The pre-concentration of yttrium(Ⅲ) ions ...

  18. Development of Yttrium alloy ion source and its application in nanofabrication

    CERN Document Server

    Kukharchyk, Nadezhda; Mazarov, Swetlana; Bushev, Pavel; Wieck, Andreas; Mazarov, Paul

    2016-01-01

    We present a new YAuSi Liquid Metal Alloy Ion Source (LMAIS), generating focused ion beams of yttrium ions, and its prospective applications for nanofabrication, sample preparation, lithographic and implantation processes. Working parameters of the AuSiY LMAIS are similar to other gold-silicon based LMAIS. We found anomalously high emission current of triple charged Yttrium ions. Influence of Yttrium implantation on optical qualities of the implanted ion-ensembles is shown in luminescence of co-implanted Erbium ions.

  19. Synthesis and Characterization of Yttrium Doped Nano-zirconia by a Cationic Surfactant-assisted Route

    Institute of Scientific and Technical Information of China (English)

    YU Jian-Chang; HU Shen-Wei

    2006-01-01

    Recently, more and more interest has been focused on zirconia for its unique characteristics. In this paper, via the preceding preparation technique, yttrium can be successfully incorporated into nano-zirconia by a cationic surfactant-assisted route. The methods of XRD, TEM, EDS, Uv-vis and N2 adsorption-desorption are adopted to characterize the synthesized samples. The results show that the yttrium has been successfully incorporated into the zirconia lattice, and the thermal stability of yttrium doped zirconia has been enhanced remarkably.

  20. Development of yttrium alloy ion source and its application in nanofabrication

    Science.gov (United States)

    Kukharchyk, Nadezhda; Neumann, Ronna; Mazarov, Swetlana; Bushev, Pavel; Wieck, Andreas D.; Mazarov, Paul

    2016-12-01

    We present a new YAuSi Liquid Metal Alloy Ion Source (LMAIS) generating focused ion beams of yttrium ions, and its prospective applications for nanofabrication, sample preparation, lithographic and implantation processes. Working parameters of the AuSiY LMAIS are similar to other gold-silicon based LMAIS. We found anomalously high emission current of triple charged yttrium ions. Influence of yttrium implantation on optical qualities of the implanted ion-ensembles is shown in luminescence of co-implanted Erbium ions.

  1. Sol-Gel Synthesis and Antioxidant Properties of Yttrium Oxide Nanocrystallites Incorporating P-123

    OpenAIRE

    Rebeca Mellado-Vázquez; Margarita García-Hernández; Arturo López-Marure; Perla Yolanda López-Camacho; Ángel de Jesús Morales-Ramírez; Hiram Isaac Beltrán-Conde

    2014-01-01

    Yttrium oxide (Y2O3) nanocrystallites were synthesized by mean of a sol-gel method using two different precursors. Raw materials used were yttrium nitrate and yttrium chloride, in methanol. In order to promote oxygen vacancies, P-123 poloxamer was incorporated. Synthesized systems were heat-treated at temperatures from 700 °C to 900 °C. Systems at 900 °C were prepared in the presence and absence of P-123 using different molar ratios (P-123:Y = 1:1 and 2:1). Fourier transform infrared spectros...

  2. Antibacterial and antibiofilm properties of yttrium fluoride nanoparticles

    Directory of Open Access Journals (Sweden)

    Lellouche J

    2012-11-01

    Full Text Available Jonathan Lellouche,1,2 Alexandra Friedman,2 Aharon Gedanken,2 Ehud Banin11Biofilm Research Laboratory, The Mina and Everard Goodman Faculty of Life Sciences, 2Kanbar Laboratory for Nanomaterials, Department of Chemistry, Institute for Nanotechnology and Advanced Materials, Bar-Ilan University, Ramat-Gan, IsraelAbstract: Antibiotic resistance has prompted the search for new agents that can inhibit bacterial growth. Moreover, colonization of abiotic surfaces by microorganisms and the formation of biofilms is a major cause of infections associated with medical implants, resulting in prolonged hospitalization periods and patient mortality. In this study we describe a water-based synthesis of yttrium fluoride (YF3 nanoparticles (NPs using sonochemistry. The sonochemical irradiation of an aqueous solution of yttrium (III acetate tetrahydrate [Y(Ac3 • (H2O4], containing acidic HF as the fluorine ion source, yielded nanocrystalline needle-shaped YF3 particles. The obtained NPs were characterized by scanning electron microscopy and X-ray elemental analysis. NP crystallinity was confirmed by electron and powder X-ray diffractions. YF3 NPs showed antibacterial properties against two common bacterial pathogens (Escherichia coli and Staphylococcus aureus at a µg/mL range. We were also able to demonstrate that antimicrobial activity was dependent on NP size. In addition, catheters were surface modified with YF3 NPs using a one-step synthesis and coating process. The coating procedure yielded a homogeneous YF3 NP layer on the catheter, as analyzed by scanning electron microscopy and energy dispersive spectroscopy. These YF3 NP-modified catheters were investigated for their ability to restrict bacterial biofilm formation. The YF3 NP-coated catheters were able to significantly reduce bacterial colonization compared to the uncoated surface. Taken together, our results highlight the potential to further develop the concept of utilizing these metal fluoride NPs

  3. Fabrication of aluminum foam from aluminum scrap Hamza

    Directory of Open Access Journals (Sweden)

    O. A. Osman1 ,

    2015-02-01

    Full Text Available In this study the optimum parameters affecting the preparation of aluminum foam from recycled aluminum were studied, these parameters are: temperature, CaCO3 to aluminum scrap wt. ratio as foaming agent, Al2O3 to aluminum scrap wt. ratio as thickening agent, and stirring time. The results show that, the optimum parameters are the temperature ranged from 800 to 850oC, CaCO3 to aluminum scrap wt. ratio was 5%, Al2O3 to aluminum scrap wt. ratio was 3% and stirring time was 45 second with stirring speed 1200 rpm. The produced foam apparent densities ranged from 0.40-0.60 g/cm3. The microstructure of aluminum foam was examined by using SEM, EDX and XRD, the results show that, the aluminum pores were uniformly distributed along the all matrices and the cell walls covered by thin oxide film.

  4. Synthesis and characterization of yttrium aluminium garnet (YAG powders

    Directory of Open Access Journals (Sweden)

    Magdalena Zarzecka-Napierala

    2007-12-01

    Full Text Available In this paper synthesis and characterization of YAG powders, prepared by a process based on complexing properties of citric acid, was reported. Influence of citric acid estrification induced by 2-propanol or ethylene glycol on the system homogeneity was investigated. These reagents were introduced to aqueous solution of yttrium and aluminium nitrates. A variety of powders from Al2O3-Y2O3 system with different phase composition were obtained by altering the citrate to nitrate ratio. Evolution of the powders phase composition vs. temperature was investigated using DTA/TG, XRD, and FT-IR methods. The most interesting results were observed in case of the citric acid–propanol–relative nitrates system. The mole ratio of these reagents equal to 1:2.5:2.5 (nitrates (Al,Y:citric acid:2-propanol allowed to synthesize pure YAG phase powders at temperature as low as 950°C.

  5. Yttrium-90 Radioembolization of Hepatic Metastases from Colorectal Cancer

    Directory of Open Access Journals (Sweden)

    Raval eMihir

    2014-07-01

    Full Text Available Liver metastases from colorectal cancer (CRC result in substantial morbidity and mortality. The primary treatment is systemic chemotherapy, and in selected patients, surgical resection; however, for patients who are not surgical candidates and/or fail systemic chemotherapy, liver-directed therapies are increasingly being utilized. Yttrium-90 (Y-90 microsphere therapy, also known as selective internal radiation therapy (SIRT or radioembolization, has proven to be effective in terms of extending time to progression of disease and also providing survival benefit. This review focuses on the use of Y-90 microsphere therapy in the treatment of liver metastases from CRC, including a comprehensive review of published clinical trials and prospective studies conducted thus far. We review the methodology, outcomes and side effects of Y-90 microsphere therapy for metastatic CRC

  6. Thermal decomposition of yttrium(III) hexanoate in argon

    DEFF Research Database (Denmark)

    Grivel, Jean-Claude; Suarez Guevara, Maria Josefina; Attique, Fahmida;

    2015-01-01

    The thermal decomposition of yttrium(III) hexanoate (Y(C5H11CO2)3)·xH2O in argon was studied by means of thermogravimetry, differential thermal analysis, IR-spectroscopy, X-ray diffraction at a laboratory Cu-tube source and in-situ experiments at a synchrotron radiation source as well as hot...... into Y2O2CO3 with release of CO2 and 6-undecanone between 280°C and 490°C. A side reaction appears to yield elemental carbon and volatile decane (C10H22). Y2O2CO3 is converted to Y2O3 with release of CO2 between 500°C and 975°C....

  7. Biosynthesis of Yttrium oxide nanoparticles using Acalypha indica leaf extract

    Indian Academy of Sciences (India)

    S K Kannan; M Sundrarajan

    2015-08-01

    In this study, the synthesis of Yttrium oxide (Y2O3) nanoparticles was carried out from Acalypha indica leaf extract. The synthesized nanoparticles were characterized by using X-ray diffraction, scanning electron microscope, energy-dispersive X-ray spectrometer and transmission electron microscope for structural confirmation. The studies clearly indicate that the synthesized Y2O3 nanoparticle is a crystalline material with a particle size from 23 to 66 nm. Further analysis was carried out by Fourier transform infrared spectroscopy, to provide the evidence for the presence of Y–O–Y and O–Y–O stretchings in the synthesized Y2O3 nanoparticles. Thermogravimetric and differential scanning calorimetry analyses gave the thermal stability of Y2O3 nanoparticles. The results of the antibacterial studies conducted by using the synthesized Y2O3 revealed an increasing rate of antibacterial behaviour with pathogens.

  8. Local structure of oxygen-deficient Yttrium oxide

    Institute of Scientific and Technical Information of China (English)

    CHENG Xue-Rui; DAI Hai-Yang; QI Ze-Ming; WANG Yu-Yin; ZHANG Guo-Bin

    2013-01-01

    Yttrium oxide thin films have been deposited on Si (100) substrate by using pulsed laser deposition (PLD) method.X-ray diffraction (XRD),hard and soft X-ray absorption spectroscopy (XAFS) are employed to investigate the origin of oxygen vacancies and their influence on the structure and atomic distributions.The XRD results indicate that the Y2O3 thin films strongly orient the (111) axis of the cubic structure.Analyses on the Y K-edge extended X-ray absorption fine structures reveal that the coordination number of Y atoms decreases and the bond length of Y-O contracts due to the loss of oxygen atoms.The X-ray absorption near edge structure analysis together with a theoretical approach further confirms the oxygen vacancies formation and their possible location.

  9. Photocatalysis of Yttrium Doped BaTiO3 Nanofibres Synthesized by Electrospinning

    Directory of Open Access Journals (Sweden)

    Zhenjiang Shen

    2015-01-01

    Full Text Available Yttrium doped barium titanate (BT nanofibres (NFs with significant photocatalytic effect were successfully synthesized by electrospinning. Considering the necessary factors for semiconductor photocatalysts, a well-designed procedure was carried out to produce yttrium doped BT (BYT NFs. In contrast to BYT ceramics powders and BT NFs, BYT NFs with pure perovskite phase showed much enhanced performance of photocatalysis. The surface modification in electrospinning and subsequent annealing, the surface spreading of transition metal yttrium, and the narrowed band gap energy in yttrium doping were all contributed to the final novel photocatalytic effect. This work provides a direct and efficient route to obtain doped NFs, which has a wide range of potential applications in areas based on complex compounds with specific surface and special doping effect.

  10. Synthesis,structure and catalytic behavior of yttrium complexes bearing a diaminobis(phenolate) ligand

    Institute of Scientific and Technical Information of China (English)

    SONG FengKui; YAN ChunHui; SUN HongMei; YAO YingMing; SHEN Qi; ZHANG Yong

    2009-01-01

    Yttrium complexes stabilized by a diaminobis(phenolate) ligand were synthesized and their catalytic behavior was explored. Reaction of YCI3 with 1 equiv of LNa2 [L=Me2NCH2CH2N{CH2-(2-O-C6H2-tBu2-3,5)}2]gave the yttrium chloride LYCI(THF) (1) in 92% yield. Complex 1 can be used as starting material to prepare the yttrium amido derivative. Complex 1 reacted with 1 equiv of LiNPh2 in THF to afford the expected yttrium amido complex LYNPh2 (2) in high yield. Both of complexes 1 and 2 have been well detected by elemental analysis,NMR spectra and single-crystal X-ray analysis. It was found that complex 2 can efficiently initiate the ring-opening polymerization of L-lactide and ε-caprolactone,and a controlled manner is observed in the former case.

  11. Sorptive separation of yttrium and cerium on a weakly basic anionite

    Science.gov (United States)

    Cheremisina, O. V.; Ponomareva, M. A.; Chirkst, D. E.; Lobacheva, O. L.; Shul'gin, I. A.

    2015-01-01

    The sorption of complex yttrium ions with Trilon B onto the weakly basic anionite D-403 in nitrate form from an acidic medium at pH 3 with constant ionic strength (NaNO3, 1 mol/kg) is investigated. A thermodynamic evaluation of the sorption isotherm of anionic yttrium complexes is performed using a method based on the linearization of the equation of the law of active mass, modified for ionic exchange reactions. The ionic exchange constant, the Gibbs free energy of ionic exchange, the capacity of the anionite, and the sorption limit of ethylenediaminetetraacetatoyttrate ions (EDTA yttrate ions) are calculated. Using a frontal version of ion exchange chromatography, cerium and yttrium are separated on D-403 anionite with a fraction of pure yttrium at the column outlet of no less than 30%.

  12. Polymer Derived Yttrium Silicate Ablative TPS Materials for Next-Generation Exploration Missions Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Through the proposed NASA SBIR program, NanoSonic will optimize its HybridSil® derived yttrium silicates to serve as next-generation reinforcement for carbon...

  13. Structural study of nanosized yttrium-doped CaMnO3 perovskites

    Indian Academy of Sciences (India)

    J Zagorac; A Zarubica; A Radosavljevic-Mihajlovic; D Zagorac; B Matovic

    2014-05-01

    Nanostructured compounds with general formula Ca1-YMnO3 (0 ≤ ≤ 1) were synthesized by modified glycine nitrate procedure. In the next step, we have investigated crystal structure and microstructure of the synthesized samples using X-ray methods and Rietveld analysis. Focus of this research was the structural stability of the yttrium-doped CaMnO3 perovskite phases, which crystallize in orthorhombic space group Pnma. We observed that the unit cell volumes of the investigated compounds increase proportionally with yttrium amount. Furthermore, we investigated the influence of yttrium amount on Mn–O bond angles and distances, tilting of MnO6 octahedra and deformation due to the presence of Jahn–Teller distortion around Mn3+ cation. In order to estimate effective coordination of and sites, bond valence calculations (BVC) were performed for and site cations. Finally, the photoelectron spectroscopy (XPS) method was applied in order to follow yttrium concentration in the perovskite phases.

  14. Recovery of yttrium from fluorescent powder of cathode ray tube, CRT: Zn removal by sulphide precipitation

    Energy Technology Data Exchange (ETDEWEB)

    Innocenzi, Valentina, E-mail: valentina.innocenzi1@univaq.it [Department of Industrial Engineering and Information and Economy, University of L’Aquila, Via Giovanni Gronchi n.18, Nucleo Ind.le di Pile, 67100 L’Aquila (Italy); De Michelis, Ida; Ferella, Francesco [Department of Industrial Engineering and Information and Economy, University of L’Aquila, Via Giovanni Gronchi n.18, Nucleo Ind.le di Pile, 67100 L’Aquila (Italy); Beolchini, Francesca [Department of Marine Sciences, Polytechnic Institute of Marche, Via Brecce Bianche, 60131 Ancona (Italy); Kopacek, Bernd [SAT, Austrian Society for Systems Engineering and Automation, Gurkasse 43/2, A-1140 Vienna (Austria); Vegliò, Francesco [Department of Industrial Engineering and Information and Economy, University of L’Aquila, Via Giovanni Gronchi n.18, Nucleo Ind.le di Pile, 67100 L’Aquila (Italy)

    2013-11-15

    Highlights: • Treatment of fluorescent powder of CRT waste. • Factorial experimental designs to study acid leaching of fluorescent powder and the purification of leach liquors. • Recover of yttrium by precipitation using oxalic acid. • Suitable flowsheet to recover yttrium from fluorescent powder. - Abstract: This work is focused on the recovery of yttrium and zinc from fluorescent powder of cathode ray tube (CRT). Metals are extracted by sulphuric acid in the presence of hydrogen peroxide. Leaching tests are carried out according to a 2{sup 2} full factorial plan and the highest extraction yields for yttrium and zinc equal to 100% are observed under the following conditions: 3 M of sulphuric acid, 10% v/v of H{sub 2}O{sub 2} concentrated solution at 30% v/v, 10% w/w pulp density, 70 °C and 3 h of reaction. Two series of precipitation tests for zinc are carried out: a 2{sup 2} full factorial design and a completely randomized factorial design. In these series the factors investigated are pH of solution during the precipitation and the amount of sodium sulphide added to precipitate zinc sulphide. The data of these tests are used to describe two empirical mathematical models for zinc and yttrium precipitation yields by regression analysis. The highest precipitation yields for zinc are obtained under the following conditions: pH equal to 2–2.5% and 10–12% v/v of Na{sub 2}S concentrated solution at 10% w/v. In these conditions the coprecipitation of yttrium is of 15–20%. Finally further yttrium precipitation experiments by oxalic acid on the residual solutions, after removing of zinc, show that yttrium could be recovered and calcined to obtain the final product as yttrium oxide. The achieved results allow to propose a CRT recycling process based on leaching of fluorescent powder from cathode ray tube and recovery of yttrium oxide after removing of zinc by precipitation. The final recovery of yttrium is 75–80%.

  15. Optical constants of yttrium-iron garnet single-crystal film structures

    Science.gov (United States)

    Sobol, V. R.; Volchik, T. V.; Arabei, S. M.; Korzun, B. V.; Kalanda, N. A.

    2009-03-01

    Light-attenuation spectra of yttrium-iron garnet single-crystal film structures grown on a gallium-gadolinium garnet substrate by liquid-phase epitaxy from the undercooled solution in the melt have been studied and compared with those of bulk yttrium-iron garnet samples. The calculated optical constants are discussed taking into account the influence of crystal field on the splitting of the energy states of iron ions in the film samples.

  16. Pulsed Laser Deposition of YBCO With Yttrium Oxide Buffer Layers (Postprint)

    Science.gov (United States)

    2012-02-01

    AFRL-RZ-WP-TP-2012-0092 PULSED LASER DEPOSITION OF YBCO WITH YTTRIUM OXIDE BUFFER LAYERS (POSTPRINT) Paul N. Barnes, Timothy J. Haugan...Paper Postprint 01 January 2002 – 01 January 2004 4. TITLE AND SUBTITLE PULSED LASER DEPOSITION OF YBCO WITH YTTRIUM OXIDE BUFFER LAYERS (POSTPRINT...Textured metallic substrate based HTS coated conductors with the YBCO /CeO2/YSZ/CeO2/Ni architecture have already been shown to exhibit high current

  17. Morpho-structural and luminescent investigations of niobium activated yttrium tantalate powders

    Energy Technology Data Exchange (ETDEWEB)

    Hristea, Amalia [' Raluca Ripan' Institute for Research in Chemistry, Fantanele 30, R-400294 Cluj-Napoca (Romania); Faculty of Chemistry and Chemical Engineering, ' Babes-Bolyai' University, 11 Arany Janos, 400028 Cluj-Napoca (Romania)], E-mail: amaliahristea@gmail.com; Popovici, Elisabeth-Jeanne; Muresan, Laura [' Raluca Ripan' Institute for Research in Chemistry, Fantanele 30, R-400294 Cluj-Napoca (Romania); Stefan, Maria [' Raluca Ripan' Institute for Research in Chemistry, Fantanele 30, R-400294 Cluj-Napoca (Romania); Faculty of Chemistry and Chemical Engineering, ' Babes-Bolyai' University, 11 Arany Janos, 400028 Cluj-Napoca (Romania); Grecu, Rodica [' Raluca Ripan' Institute for Research in Chemistry, Fantanele 30, R-400294 Cluj-Napoca (Romania); Johansson, Anders [Angstrom Laboratory, Department of Materials Chemistry, Uppsala University, Box 538, 751 21 Uppsala (Sweden); Boman, Mats [Angstrom Laboratory, Department of Materials Chemistry, Uppsala University, Box 538, 751 21 Uppsala (Sweden)], E-mail: mats.boman@mkem.uu.se

    2009-03-05

    Yttrium tantalate-based phosphors are a class of efficient luminescent materials used in medical imaging applications. The paper presents the influence of activator concentration, firing regime and flux nature on the crystalline structure, morphology and luminescent characteristics of niobium activated yttrium tantalate powders. Phosphors samples were prepared by solid-state reaction route and their properties were investigated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), photoluminescence (PL) measurements and scanning electron microscopy (SEM)

  18. Electrically conductive anodized aluminum coatings

    Science.gov (United States)

    Alwitt, Robert S. (Inventor); Liu, Yanming (Inventor)

    2001-01-01

    A process for producing anodized aluminum with enhanced electrical conductivity, comprising anodic oxidation of aluminum alloy substrate, electrolytic deposition of a small amount of metal into the pores of the anodized aluminum, and electrolytic anodic deposition of an electrically conductive oxide, including manganese dioxide, into the pores containing the metal deposit; and the product produced by the process.

  19. China’s Aluminum Resources

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    <正> The aluminum industry makes one of the keyindustries in China’s industrial and agriculturalmodernization and features a high degree ofrelevance with all industries.Of all the 124existing industries in China,113 use aluminum,representing an industrial relevance rate of91%.The consumption of aluminum is also ofhigh relevance with China’s GDP.

  20. Aluminum for Plasmonics

    Science.gov (United States)

    2014-01-01

    in plasmon-enhanced light harvesting,14 photocatalysis ,511 surface- enhanced spectroscopies,1216 optics-based sensing,1722 nonlinear optics,2326...optical response of Al nanoparticles has appeared inconsistent relative to calculated spectra, even forwell-characterized geometries. Some studies have...model- ing their optical response. These results pro- vide a method for estimating the metallic purity of aluminum nanoparticles directly from their

  1. Strengthening and Toughening Effect of Yttrium on Al2O3/TiCN Ceramic Tool Material

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The strengthening and toughening effect of yttrium on an advanced Al2O3/TiCN ceramic tool material was studied by means of SEM, TEM and energy spectrum analysis. Results showed that yttrium can react with the impurity elements such as W, Fe, Cr, etc. Thus, the interfaces between ceramic phases are purified and the interfacial binding strength is increased. As a result, the mechanical properties of the Al2O3/TiCN ceramic tool material reinforced with yttrium are improved significantly. In addition, the effect of yttrium on particle strengthening of the solid solution TiCN may partly contribute to the improvement of the mechanical properties.

  2. Impacts of yttrium substitution on FMR line-width and magnetic properties of nickel spinel ferrites

    Energy Technology Data Exchange (ETDEWEB)

    Ishaque, M., E-mail: ishaqdgk1@gmail.com [Department of Physics, Bahauddin Zakariya University, Multan 60800 (Pakistan); Khan, Muhammad Azhar, E-mail: azhar.khan@iub.edu.pk [Department of Physics, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan); Ali, Irshad; Khan, Hasan M. [Department of Physics, Bahauddin Zakariya University, Multan 60800 (Pakistan); Iqbal, M. Asif [Department of Physics, Bahauddin Zakariya University, Multan 60800 (Pakistan); College of E & ME, National University of Science and Technology, Islamabad (Pakistan); Islam, M.U. [Department of Physics, Bahauddin Zakariya University, Multan 60800 (Pakistan); Warsi, Muhammad Farooq [Department of Chemistry, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan)

    2015-05-15

    The influence of yttrium (Y) substitution on ferromagnetic resonance (FMR), initial permeability, and magnetic properties of NiFe{sub 2}O{sub 4} ferrites were investigated. It was observed that the FMR line-width decreases with yttrium contents for the substitution level 0≤×≤0.06. Beyond this, the FMR line-width increases with yttrium contents. The nominal composition NiY{sub 0.12}Fe{sub 1.88}O{sub 4} exhibited the smallest FMR line-width ~282 Oe. A significant change in FMR position of nickel–yttrium (Ni–Y) ferrites was observed and it found to exist between 4150 and 4600 Oe. The saturation magnetization was observed to decrease with the increase of yttrium contents and this was referred to the redistribution of cations on octahedral. The coercivity increased from 15 Oe to 59 Oe by increasing the yttrium concentration. The initial permeability decreased from 110 to 35 at 1 MHz by the incorporation of yttrium and this was attributed to the smaller grains which may obstruct the domain wall movement and impede the domain wall motion. The magnetic loss factors of substituted samples exhibit decreasing behavior in the frequency range 1 kHz to 10 MHz. The smaller FMR line-width and reduced magnetic loss factor of the investigated samples suggest the possible use of these materials in high frequency applications. - Highlights: • Influence of Y{sup 3+} substitution on the properties of nickel ferrites is investigated. • Very small FMR line-width (282 Oe) is exhibited by these substituted ferrites. • Fourfold increase in coercivity was observed for NiY{sub 0.24}Fe{sub 1.76}O{sub 4} ferrites.

  3. Aluminum microstructures on anodic alumina for aluminum wiring boards.

    Science.gov (United States)

    Jha, Himendra; Kikuchi, Tatsuya; Sakairi, Masatoshi; Takahashi, Hideaki

    2010-03-01

    The paper demonstrates simple methods for the fabrication of aluminum microstructures on the anodic oxide film of aluminum. The aluminum sheets were first engraved (patterned) either by laser beam or by embossing to form deep grooves on the surface. One side of the sheet was then anodized, blocking the other side by using polymer mask to form the anodic alumina. Because of the lower thickness at the bottom part of the grooves, the part was completely anodized before the complete oxidation of the other parts. Such selectively complete anodizing resulted in the patterns of metallic aluminum on anodic alumina. Using the technique, we fabricated microstructures such as line patterns and a simple wiring circuit-board-like structure on the anodic alumina. The aluminum microstructures fabricated by the techniques were embedded in anodic alumina/aluminum sheet, and this technique is promising for applications in electronic packaging and devices.

  4. A thermodynamic assessment of the iron–yttrium system

    Energy Technology Data Exchange (ETDEWEB)

    Kardellass, S., E-mail: saidkardellass@yahoo.fr [Laboratoire de Thermodynamique et Energétique, LTE, Université Ibn-Zohr, B.P. 8106 Agadir (Morocco); Servant, C., E-mail: colette.servant@orange.fr [Laboratoire de Physicochimie de l’Etat Solide, ICMMO, Université Paris-Sud, 91405 Orsay Cedex (France); Selhaoui, N.; Iddaoudi, A.; Amar, M. Ait; Bouirden, L. [Laboratoire de Thermodynamique et Energétique, LTE, Université Ibn-Zohr, B.P. 8106 Agadir (Morocco)

    2014-01-15

    Highlights: • Rare earth elements are increasingly used in advanced materials (permanent magnets, hydrogen storage alloys, luminescent materials…). • To our knowledge, this system was not previously optimized. • Two formalisms were compared for the excess terms of the solution phases. • A consistent set of thermodynamic parameters was optimized (good agreement between calculation and experiments). • This work is the start point for the study of ternary systems with RE. -- Abstract: The thermodynamic modeling of the Iron–Yttrium binary system was carried out with the help of the CALPHAD (CALculation of PHAse Diagram) method. The excess term of the Gibbs energy of the solution phases (liquid, b.c.c., f.c.c. and h.c.p.) was assessed with the recent exponential temperature dependence of the interaction energies by Kaptay [1–3] and compared with the linear temperature dependence of Redlich–Kister [4] polynomial equation results. The intermetallic compounds Fe{sub 23}Y{sub 6} and Fe{sub 2}Y in this binary system which have a homogeneity range, were treated by a two-sublattice model with convenient substitution in each sublattice [5,6]. The others were considered as stoichiometric compounds. A consistent set of thermodynamic parameters leading to a reasonable agreement between the calculated results and literature data was obtained for this system which has not been previously optimized.

  5. Ab initio calculations of yttrium nitride: structural and electronic properties

    Energy Technology Data Exchange (ETDEWEB)

    Zerroug, S.; Ali Sahraoui, F. [Universite Ferhat Abbas, Laboratoire d' Optoelectronique et Composants, Departement de Physique, Setif (Algeria); Bouarissa, N. [King Khalid University, Department of Physics, Faculty of Science, P.O. Box 9004, Abha (Saudi Arabia)

    2009-11-15

    Using first principles total energy calculations within the full-potential linearized augmented plane wave method, we have studied the structural and electronic properties of yttrium nitride (YN) in the three phases, namely wurtzite, caesium chloride and rocksalt structures. The calculations are performed at zero and under hydrostatic pressure. In agreement with previous findings, it is found that the favored phase for YN is the rocksalt-like structure. We predict that at zero pressure YN in the rocksalt structure is a semiconductor with an indirect bandgap of 0.8 eV. A phase transition from a rocksalt to a caesium chloride structure is found to occur at {proportional_to}134 GPa. Besides, a transition from an indirect ({gamma}-X) bandgap semiconductor to a direct (X-X) one is predicted at pressure of {proportional_to}84 GPa. For the electron effective mass of rocksalt YN, these are the first results, to our knowledge. The information derived from the present study may be useful for the use of YN as an active layer in electronic devices such as diodes and transistors. (orig.)

  6. Optical and structural characterization of yttrium calcium borate glasses

    Science.gov (United States)

    Santos, Cristiane; Meneses, Domingos D. S.; Echegut, Patrick; Neuville, Daniel R.; Hernandes, Antonio C.; Ibanez, Alain

    2010-03-01

    Structural and optical properties of new stable glasses in the Y2O3 -- CaO -- B2O3 system, containing the same Y/Ca ratio as the YCa4O(BO3)3 (YCOB) crystal, were determined from Raman and reflectance infrared spectroscopy [1]. We have obtained the optical functions using a dielectric function model and their evolution with composition are associated with an increase in the number of non-bridging oxygen and to calcium/yttrium oxides content with the formation of pentaborate, metaborate, orthoborate and pyroborate groups. The orthoborate and pyroborate signatures increase with increasing the modifier cations. Refractive indexes values (from 1.597 to 1.627 at λ = 2 μm) are in good agreement with those of the YCOB crystal, an indication that these glasses are potential candidates for doping with rare-earth ions for optical applications. [4pt] [1] C. N. Santos, D.D.S. Meneses, P. Echegut, D. R. Neuville, A. C. Hernandes, A. Ibanez, Appl. Phys. Lett. 94, 151901(2009).

  7. MCrAlY bond coat with enhanced yttrium

    Energy Technology Data Exchange (ETDEWEB)

    Jablonski, Paul D.; Hawk, Jeffrey A.

    2016-08-30

    One or more embodiments relates to a method of producing an MCrAlY bond coat comprising an MCrAlY layer in contact with a Y--Al.sub.2O.sub.3 layer. The MCrAlY layer is comprised of a .gamma.-M solid solution, a .beta.-MAl intermetallic phase, and Y-type intermetallics. The Y--Al.sub.2O.sub.3 layer is comprised of Yttrium atoms coordinated with oxygen atoms comprising the Al.sub.2O.sub.3 lattice. The method comprises depositing an MCrAlY material on a substrate, applying an Y.sub.2O.sub.3 paste, and heating the substrate in a non-oxidizing atmosphere at a temperature between 400-1300.degree. C. for a time sufficient to generate the Y--Al.sub.2O.sub.3 layer. Both the MCrAlY layer and the Y--Al.sub.2O.sub.3 layer have a substantial absence of Y.sub.2O.sub.3, YAG, and YAP phases.

  8. Aluminum Carbothermic Technology

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, Marshall J.

    2005-03-31

    This report documents the non-proprietary research and development conducted on the Aluminum Carbothermic Technology (ACT) project from contract inception on July 01, 2000 to termination on December 31, 2004. The objectives of the program were to demonstrate the technical and economic feasibility of a new carbothermic process for producing commercial grade aluminum, designated as the ''Advanced Reactor Process'' (ARP). The scope of the program ranged from fundamental research through small scale laboratory experiments (65 kW power input) to larger scale test modules at up to 1600 kW power input. The tasks included work on four components of the process, Stages 1 and 2 of the reactor, vapor recovery and metal alloy decarbonization; development of computer models; and economic analyses of capital and operating costs. Justification for developing a new, carbothermic route to aluminum production is defined by the potential benefits in reduced energy, lower costs and more favorable environmental characteristics than the conventional Hall-Heroult process presently used by the industry. The estimated metrics for these advantages include energy rates at approximately 10 kWh/kg Al (versus over 13 kWh/kg Al for Hall-Heroult), capital costs as low as $1250 per MTY (versus 4,000 per MTY for Hall-Heroult), operating cost reductions of over 10%, and up to 37% reduction in CO2 emissions for fossil-fuel power plants. Realization of these benefits would be critical to sustaining the US aluminum industries position as a global leader in primary aluminum production. One very attractive incentive for ARP is its perceived ability to cost effectively produce metal over a range of smelter sizes, not feasible for Hall-Heroult plants which must be large, 240,000 TPY or more, to be economical. Lower capacity stand alone carbothermic smelters could be utilized to supply molten metal at fabrication facilities similar to the mini-mill concept employed by the steel industry

  9. Studies on the synthesis of europium activated yttrium oxide by wet-chemical method

    Energy Technology Data Exchange (ETDEWEB)

    Muresan, Laura [Raluca Ripan Institute for Research in Chemistry, Fantanele 30, 400294 Cluj-Napoca (Romania)], E-mail: laura_muresan2003@yahoo.com; Popovici, Elisabeth-Jeanne; Grecu, Rodica [Raluca Ripan Institute for Research in Chemistry, Fantanele 30, 400294 Cluj-Napoca (Romania); Tudoran, Lucian Barbu [Electronic Microscopy Center, Babes-Bolyai University, 400028 Cluj-Napoca (Romania)

    2009-03-05

    Europium activated yttrium oxide phosphor powders (Y{sub 2}O{sub 3}:Eu{sup 3+}) were prepared from yttrium-europium precursors obtained by wet-chemical method. With this purpose in view, precursors were prepared using the reagent simultaneous addition SimAdd technique from yttrium-europium nitrate and chloride as rare-earth supplier and urea, ammonium oxalate, ammonium carbonate and oxalic acid as precipitating agents. Precursors, obtained under controlled concentration, temperature and pH conditions, were fired at 1200 deg. C in order to generate Y{sub 2}O{sub 3}:Eu{sup 3+} phosphor powders. Yttrium-europium precursors and Y{sub 2}O{sub 3}:Eu{sup 3+} phosphor powders were investigated by FTIR, TGA-DTA, X-ray diffraction (XRD), scanning electronic microscopy (SEM) and photoluminescence spectroscopy (PL) in order to put in evidence the influence of the quality of yttrium-europium precursors obtained by wet-chemical method, using the SimAdd technique on the properties of Y{sub 2}O{sub 3}:Eu{sup 3+} phosphor powders.

  10. Laser assisted foaming of aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Kathuria, Y.P. [Laser X Co. Ltd., Aichi (Japan)

    2001-09-01

    Recently aluminum foams have evoked considerable interest as an alternative material owing to their wide range of applications ranging from microelectronics, through automobiles to aerospace industries. The manufacturing techniques and characterization methods for aluminum foams require further development to achieve effective and economical use of this material. In this communication the authors demonstrate the feasibility of unidirectional and localized expansion of the aluminum foam using the Nd-YAG/CO{sub 2} laser and powder metallurgy. (orig.)

  11. Preparation of nanosized yttrium doped CeO2 catalyst used for photocatalytic application

    Directory of Open Access Journals (Sweden)

    A. Akbari-Fakhrabadi

    2015-09-01

    Full Text Available In the present work, the pure CeO2 and yttrium doped CeO2 nanopowders were synthesized by the nitrate-fuel self-sustaining combustion method and calcined at 700 °C for 2 h. X-ray diffraction (XRD and high resolution electron transmission microscopy (HRTEM results demonstrated a cubic fluorite with high purity and the crystallite sizes less than 20 nm calculated from Scherrer’s formula. The BET specific surface area of yttrium doped CeO2 samples showed high values than those of pure CeO2. The photocatalytic activity of yttrium doped CeO2 showed high degradation of Rhodamine B solution under visible light illumination.

  12. Synthesis of yttrium doped nanocrystalline ZnO and its photocatalytic activity in methylene blue degradation

    OpenAIRE

    2016-01-01

    Yttrium doped zinc oxide was prepared by microwave irradiation of Y (NO3)3·6H2O and Zn(NO3)2·4H2O as precursors, in ethanol–water medium. Highly polar ethanol–water medium (30/70, v/v) with hexamine and urea assist the formation of ZnO nuclei very rapidly in a specific fashion. Furthermore, Y3+ ions infiltration into Zn(OH)2 precipitate was facilitated by microwaves (2.45 GHz, 950 W). Yttrium doped nanocrystalline ZnO (ZnO-99 and ZnO-95) was formed with 1 and 5 mol% yttrium precursor. The pow...

  13. Analysis on insulator–metal transition in yttrium doped LSMO from electron density distribution

    Indian Academy of Sciences (India)

    S Israel; S Saravana Kumar; R Renuretson; R A J R Sheeba; R Saravanan

    2012-02-01

    Yttrium doped LSMO (La1−SrMnO3) was prepared using sol–gel technique and analysed for the insulator–metal transition fromcharge density variation in the unit cell with respect to different stoichiometric inclusion of yttrium. X-ray powder diffraction profiles of the samples were obtained and the well known Rietveld method and a versatile tool called maximum entropy method (MEM) were used for structural and profile refinement. The charge density in the unit cell was constructed using refined structure factors and was analysed. The charge ordering taking place in the insulator–metal transition was investigated and quantified. The insulator–metal transition was found to occur when 20% of La/Sr atoms were replaced by yttrium. The changes in the charge environment have also been analysed.

  14. Influence of Yttrium Implantation on Oxidation Behavior of Pure Nickel at 1 000℃

    Institute of Scientific and Technical Information of China (English)

    JIANG Shi-hang; JIN Hui-ming; YAN Kun; GONG Ze-xiang

    2005-01-01

    Isothermal and cyclic oxidation behaviors of pure and yttrium-implanted nickel were studied at 1000℃ in air. The oxide scales formed on nickel substrates were performed using SEM and TEM. It was found that Yimplantation greatly improved the anti-oxidation ability of nickel both in isothermal and cyclic oxidizing experiments. Laser Raman microscopy was also used to study the stress status of oxide scales formed on nickel with and without yttrium. The main reason for the improvement in antioxidation and adhesion of oxide scale was Y-implantation greatly reduced the grain size of NiO and lowered the compressive stress within the scale. Yttrium implantation enhanced the adhesion of protective NiO oxide scale formed on nickel substrate.

  15. Fractionation of yttrium and holmium during basaltic soil weathering

    Science.gov (United States)

    Thompson, Aaron; Amistadi, Mary Kay; Chadwick, Oliver A.; Chorover, Jon

    2013-10-01

    The anomalously low affinity of yttrium (Y) for iron (Fe) (oxyhydr)oxides relative to lanthanides with similar ionic radius (e.g., Ho) has been demonstrated in experiments with isolated Fe minerals and in a variety of marine systems that contain high concentrations of solid phase Fe. However, it has not previously been demonstrated to occur during soil genesis, despite the common observation that many soils become enriched in Fe over time. We hypothesized that Y would become progressively depleted in soils relative to Ho with increased weathering. Since, trivalent Y has an anomalously low Misono softness relative to other trivalent ions included in the rare earth element and yttrium group (REY3+), we also investigated whether soil REY fractionation reflects variation in Misono softness. To test this, we measured trends in total REY concentrations for Hawaiian soils derived from basaltic parent materials aged 0.3-4100 ky, and measured REYs released from the same samples during short-time (3 h) dissolution experiments conducted as part of a previous investigation linking dissolution with surface charge properties (Chorover et al., 2004). The chondrite-normalized Y/Ho ratios in the parent Hawaiian basalt (Chond[Y/Ho] = 0.998) and continental dust (Chond[Y/Ho] = 0.994) inputs are remarkably similar, and thus we can interpret deviations from Chond[Y/Ho] ∼ 1.0 to result from soil biogeochemical processes and not source mixing. Between 0.3 and 20 ky, the Chond[Y/Ho] ratio of the subsurface soils decreased from 0.96 ± 0.07(2σ) to 0.71 ± 0.05, and then remained unchanged across the rest of the weathering sequence. In contrast, the Chond[Y/Ho] ratio of the surface soils decreased from 0.99 ± 0.07 to 0.76 ± 0.05 at 150 ky and then, most likely due to continued dust inputs, increased to 1.04 ± 0.07 in the oldest soils. Analysis of the short-time dissolution experiments revealed preferential release of Y relative to Ho (and also La relative Pr) at intermediate pH where

  16. Synthesis of Neodymium-Doped Yttrium Aluminum Garnet (Nd∶YAG) Nano-Sized Powders by Low Temperature Combustion

    Institute of Scientific and Technical Information of China (English)

    Zhang Huashan; Su Chunhui; Han Hui; Hou Zhaoxia

    2005-01-01

    The homogeneously dispersed, less agglomerated (Nd0.01Y0.99)3Al5O12 nano-sized powders were synthesized by the low temperature combustion (LCS), using Nd2O3, Y2O3, Al(NO3)3·9H2O, ammonia water and citric acid as starting materials. This method effectively solves the problems caused by solid-state reaction at high temperature and hard agglomerates brought by the chemical precipitation method. The powders were characterized by TG-DTA, XRD, FT-IR, TEM respectively and the photoluminescence (PL) spectra of (Nd0.01Y0.99)3Al5O12 green and sintered ceramic disks were measured. The results show that the forming temperature of YAG crystal phase is 850 ℃ and YAP crystal phase appearing during the calcinations transforms to pure YAG at 1050 ℃. The particle size of the powders synthesized by the LCS is in a range of 20~50 nm depending on the thermal treatment temperatures. The effectively induced cross section (σin) with the value 4.03×10-19 cm2 of (Nd0.01Y0.99)3Al5O12 ceramics is about 44% higher than that of single crystal.

  17. Generation of Ultrashort Optical Pulses from Chromium - Forsterite and Chromium-Doped Yttrium Aluminum Garnet Tunable Solid-State Lasers.

    Science.gov (United States)

    Sennaroglu, Alphan

    In this thesis, experimental results of ultrashort pulse generation from the Cr:forsterite and Cr:YAG laser systems are presented. Ultrashort pulses from these coherent light sources are potentially important in such technological applications as fiber-optic communications, time-resolved spectroscopy of narrow-bandgap semiconductors, and medical imaging of tissues. Additive-pulse mode-locked operation of a Cr:forsterite laser was first pursued. By using a single-mode optical fiber for pulse shaping, 150-fs pulses were produced at 1.23 μm with 60 mW of average output power. However, pulse-train instabilities, cryogenic operation, and the overall complexity of the experimental setup hindered ready commercialization of this ultrashort pulse source. Regeneratively initiated self-mode-locked operation of the same laser system was then investigated. Regenerative initiation, where synchronization of the rf signal driving the modulator and the pulse repetition rate obviated the need for stringent cavity-length control, gave rise to the formation of a very stable, uninterrupted train of femtosecond pulses. Nearly transform-limited, 48-fs pulses, tunable from 1.21 to 1.27 mum, were produced with useful output powers of 360 mW at 1.23 mum. By employing the high-peak-power pulses generated from the Cr:forsterite laser in external second harmonic generation experiments, red pulses of 116 fs duration, tunable in the wavelength range from 605 to 635 nm, were obtained with power conversion efficiencies approaching 10%. In the next set of experiments, the continuous -wave (cw) power performance of a Cr:YAG laser was characterized as a function of various operating laser parameters. As high as 1.9 W of useful cw output power was obtained at 1.45 μm with a 2% transmitting output coupler when the gain medium was thermoelectrically cooled at 3 ^circC, significantly exceeding the results previously reported in the literature. Self -mode-locked operation of this laser system was also achieved for the first time. Using both regenerative initiation and continuous-wave self-mode-locking techniques, nearly transform-limited, 120-fs pulses were produced at 1.52 mum, with as high as 440 mW of useful output power.

  18. Fast signal processing of a yttrium-aluminum-perovskite:Ce detector for synchrotron x-ray experiments

    Science.gov (United States)

    Harada, Masaaki; Sakurai, Kenji; Saitoh, Kazuhiro; Kishimoto, Shunji

    2001-11-01

    An amplifier has been developed to form narrow pulses of less than 100 ns for a YAP:Ce scintillator, which appears promising as a detector for high-counting rate x-ray measurements. The performance of the detector system has been evaluated with monochromatic 8, 16.5, and 25 keV synchrotron x-ray photons at the Photon Factory. The whole deadtime obtained was 84 ns, which is around 3.5 times the decay time of the scintillation (25 ns), indicating that the present system is almost optimum. It has been found that the counting loss for 1 M counts/s is only 8%-9%, and that the detector can count extremely strong photons up to 5 M counts/s.

  19. Rare earth activated yttrium aluminate phosphors with modulated luminescence.

    Science.gov (United States)

    Muresan, L E; Popovici, E J; Perhaita, I; Indrea, E; Oro, J; Casan Pastor, N

    2016-06-01

    Yttrium aluminate (Y3 A5 O12 ) was doped with different rare earth ions (i.e. Gd(3+) , Ce(3+) , Eu(3+) and/or Tb(3+) ) in order to obtain phosphors (YAG:RE) with general formula,Y3-x-a Gdx REa Al5 O12 (x = 0; 1.485; 2.97 and a = 0.03). The synthesis of the phosphor samples was done using the simultaneous addition of reagents technique. This study reveals new aspects regarding the influence of different activator ions on the morpho-structural and luminescent characteristics of garnet type phosphor. All YAG:RE phosphors are well crystallized powders containing a cubic-Y3 Al5 O12 phase as major component along with monoclinic-Y4 Al2 O9 and orthorhombic-YAlO3 phases as the impurity. The crystallites dimensions of YAG:RE phosphors vary between 38 nm and 88 nm, while the unit cell slowly increase as the ionic radius of the activator increases. Under UV excitation, YAG:Ce exhibits yellow emission due to electron transition in Ce(3+) from the 5d level to the ground state levels ((2) F5/2 , (2) F7/2 ). The emission intensity of Ce(3+) is enhanced in the presence of the Tb(3+) ions and is decreased in the presence of Eu(3+) ions due to some radiative or non-radiative processes that take place between activator ions. By varying the rare earth ions, the emission colour can be modulated from green to white and red. Copyright © 2015 John Wiley & Sons, Ltd.

  20. Root Cause Analysis of Gastroduodenal Ulceration After Yttrium-90 Radioembolization

    Energy Technology Data Exchange (ETDEWEB)

    Lam, Marnix G. E. H. [Stanford University School of Medicine, Division of Interventional Radiology (United States); Banerjee, Subhas [Stanford University School of Medicine, Division of Gastroenterology and Hepatology (United States); Louie, John D.; Abdelmaksoud, Mohamed H. K. [Stanford University School of Medicine, Division of Interventional Radiology (United States); Iagaru, Andrei H. [Stanford University School of Medicine, Division of Nuclear Medicine and Molecular Imaging (United States); Ennen, Rebecca E.; Sze, Daniel Y., E-mail: dansze@stanford.edu [Stanford University School of Medicine, Division of Interventional Radiology (United States)

    2013-12-15

    IntroductionA root cause analysis was performed on the occurrence of gastroduodenal ulceration after hepatic radioembolization (RE). We aimed to identify the risk factors in the treated population and to determine the specific mechanism of nontarget RE in individual cases. Methods: The records of 247 consecutive patients treated with yttrium-90 RE for primary (n = 90) or metastatic (n = 157) liver cancer using either resin (n = 181) or glass (n = 66) microspheres were reviewed. All patients who developed a biopsy-proven microsphere-induced gastroduodenal ulcer were identified. Univariate and multivariate analyses were performed on baseline parameters and procedural data to determine possible risk factors in the total population. Individual cases were analyzed to ascertain the specific cause, including identification of the culprit vessel(s) leading to extrahepatic deposition of the microspheres. Results: Eight patients (3.2 %) developed a gastroduodenal ulcer. Stasis during injection was the strongest independent risk factor (p = 0.004), followed by distal origin of the gastroduodenal artery (p = 0.004), young age (p = 0.040), and proximal injection of the microspheres (p = 0.043). Prolonged administrations, pain during administration, whole liver treatment, and use of resin microspheres also showed interrelated trends in multivariate analysis. Retrospective review of intraprocedural and postprocedural imaging showed a probable or possible culprit vessel, each a tiny complex collateral vessel, in seven patients. Conclusion: Proximal administrations and those resulting in stasis of flow presented increased risk for gastroduodenal ulceration. Patients who had undergone bevacizumab therapy were at high risk for developing stasis.

  1. Yttrium bismuth titanate pyrochlore mixed oxides for photocatalytic hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Merka, Oliver

    2012-10-18

    In this work, the sol-gel synthesis of new non-stoichiometric pyrochlore titanates and their application in photocatalytic hydrogen production is reported. Visible light response is achieved by introducing bismuth on the A site or by doping the B site by transition metal cations featuring partially filled d orbitals. This work clearly focusses on atomic scale structural changes induced by the systematical introduction of non-stoichiometry in pyrochlore mixed oxides and the resulting influence on the activity in photocatalytic hydrogen production. The materials were characterized in detail regarding their optical properties and their atomic structure. The pyrochlore structure tolerates tremendous stoichiometry variations. The non-stoichiometry in A{sub 2}O{sub 3} rich compositions is compensated by distortions in the cationic sub-lattice for the smaller Y{sup 3+} cation and by evolution of a secondary phase for the larger Bi{sup 3+} cation on the A site. For TiO{sub 2} rich compositions, the non-stoichiometry leads to a special vacancy formation in the A and optionally O' sites. It is shown that pyrochlore mixed oxides in the yttrium bismuth titanate system represent very active and promising materials for photocatalytic hydrogen production, if precisely and carefully tuned. Whereas Y{sub 2}Ti{sub 2}O{sub 7} yields stable hydrogen production rates over time, the bismuth richer compounds of YBiTi{sub 2}O{sub 7} and Bi{sub 2}Ti{sub 2}O{sub 7} are found to be not stable under irradiation. This drawback is overcome by applying a special co-catalyst system consisting of a precious metal core and a Cr{sub 2}O{sub 3} shell on the photocatalysts.

  2. Hanford isotope project strategic business analysis yttrium-90 (Y-90)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-10-01

    The purpose of this analysis is to address the short-term direction for the Hanford yttrium-90 (Y-90) project. Hanford is the sole DOE producer of Y-90, and is the largest repository for its source in this country. The production of Y-90 is part of the DOE Isotope Production and Distribution (IP and D) mission. The Y-90 is ``milked`` from strontium-90 (Sr-90), a byproduct of the previous Hanford missions. The use of Sr-90 to produce Y-90 could help reduce the amount of waste material processed and the related costs incurred by the clean-up mission, while providing medical and economic benefits. The cost of producing Y-90 is being subsidized by DOE-IP and D due to its use for research, and resultant low production level. It is possible that the sales of Y-90 could produce full cost recovery within two to three years, at two curies per week. Preliminary projections place the demand at between 20,000 and 50,000 curies per year within the next ten years, assuming FDA approval of one or more of the current therapies now in clinical trials. This level of production would incentivize private firms to commercialize the operation, and allow the government to recover some of its sunk costs. There are a number of potential barriers to the success of the Y-90 project, outside the control of the Hanford Site. The key issues include: efficacy, Food and Drug Administration (FDA) approval and medical community acceptance. There are at least three other sources for Y-90 available to the US users, but they appear to have limited resources to produce the isotope. Several companies have communicated interest in entering into agreements with Hanford for the processing and distribution of Y-90, including some of the major pharmaceutical firms in this country.

  3. Neurofibrillary pathology and aluminum in Alzheimer's disease

    OpenAIRE

    Shin, R. W.; Lee, V.M.Y.; Trojanowski, J.Q.

    1995-01-01

    Since the first reports of aluminum-induced neurofibrillary degeneration in experimental animals, extensive studies have been performed to clarify the role played by aluminum in the pathogenesis of Alzheimer's disease (AD). Additional evidence implicating aluminum in AD includes elevated levels of aluminum in the AD brain, epidemiological data linking aluminum exposure to AD, and interactions between aluminum and protein components in the pathological lesions o...

  4. Selective Adsorption of Sodium Aluminum Fluoride Salts from Molten Aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Leonard S. Aubrey; Christine A. Boyle; Eddie M. Williams; David H. DeYoung; Dawid D. Smith; Feng Chi

    2007-08-16

    Aluminum is produced in electrolytic reduction cells where alumina feedstock is dissolved in molten cryolite (sodium aluminum fluoride) along with aluminum and calcium fluorides. The dissolved alumina is then reduced by electrolysis and the molten aluminum separates to the bottom of the cell. The reduction cell is periodically tapped to remove the molten aluminum. During the tapping process, some of the molten electrolyte (commonly referred as “bath” in the aluminum industry) is carried over with the molten aluminum and into the transfer crucible. The carryover of molten bath into the holding furnace can create significant operational problems in aluminum cast houses. Bath carryover can result in several problems. The most troublesome problem is sodium and calcium pickup in magnesium-bearing alloys. Magnesium alloying additions can result in Mg-Na and Mg-Ca exchange reactions with the molten bath, which results in the undesirable pickup of elemental sodium and calcium. This final report presents the findings of a project to evaluate removal of molten bath using a new and novel micro-porous filter media. The theory of selective adsorption or removal is based on interfacial surface energy differences of molten aluminum and bath on the micro-porous filter structure. This report describes the theory of the selective adsorption-filtration process, the development of suitable micro-porous filter media, and the operational results obtained with a micro-porous bed filtration system. The micro-porous filter media was found to very effectively remove molten sodium aluminum fluoride bath by the selective adsorption-filtration mechanism.

  5. Lack of rise in serum prolactin following yttrium-90 interstitial irradiation for acromegaly

    Energy Technology Data Exchange (ETDEWEB)

    Clark, A.J.L.; Chahal, P.; Mashiter, K.; Joplin, G.F. (Royal Postgraduate Medical School, London (UK))

    1983-11-01

    The authors have investigated the possibility that the increase in serum PRL levels observed in patients with acromegaly treated with external irradiation could be due to damage to the hypothalamus or portal vessels, by comparing the effects of yttrium-90 interstitial irradiation, which is highly localised and does not normally extend to the hypothalamus, in a similar series of patients. These results are consistent with the hypothesis; a less likely explanation is that an overgrowth of radio-resistant PRL-secreting tumour cells is occurring after external irradiation, but not after yttrium-90 implantation.

  6. The nature of photoinduced changes in the magnetostriction of yttrium-iron garnet single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Vorob' eva, N. V., E-mail: vnv@anrb.ru [Russian Academy of Sciences, Institute of Molecular and Crystals Physics (Russian Federation)

    2011-05-15

    A model of the occurrence of photoinduced changes in linear magnetostriction is proposed based on a complex experimental study of magnetostrictive strains in yttrium-iron garnets Y{sub 3}Fe{sub 5}O{sub 12} with low contents of different impurities. Analytical expressions for calculating the magnetostriction in yttrium-iron garnet single crystals with different types of doping are presented. The correlation of the photoinduced change in the magnetostriction with the crystallographic features of the samples is demonstrated. The changes in the magnetostriction constants are analyzed quantitatively for samples prepared in different ways.

  7. EXTRACTION KINETICS OF YTTRIUM WITH PURIFIED CYANEX 923 FROM NITRATE MEDIUM

    Institute of Scientific and Technical Information of China (English)

    H. Tong; Y.G. Wang; J.H. Lei; D.Q. Li; P. Tang

    2003-01-01

    Mass transfer and extraction kinetics of yttrium with the purified Cyanex 923 in nheptane from nitrate medium have been investigated by using a constant interfacial cell with laminar flow at 298K. The interfacial adsorption properties of purified Cyanex 923-heptane-0. 20mol/L (H, Na)NO3 were studied at 298K. The experimental results show that the mass transfer is controlled by diffusion and the chemical reactions are carried out in the interfacial zone. The extraction rates of yttrium were measured at different chemical compositions by varying ionic strength, pH values and the purified Cyanex 923 concentrations. The initial extraction rate equations were obtained.

  8. Magnetophotonic crystal with cerium substituted yttrium iron garnet and enhanced Faraday rotation angle.

    Science.gov (United States)

    Yoshimoto, Takuya; Goto, Taichi; Isogai, Ryosuke; Nakamura, Yuichi; Takagi, Hiroyuki; Ross, C A; Inoue, M

    2016-04-18

    Magnetophotonic crystals (MPCs) comprising cerium-substituted yttrium iron garnet (CeYIG) sandwiched by two Bragg mirrors were fabricated by vacuum annealing. CeYIG was deposited on Bragg mirrors at room temperature and annealed in 5 Pa of residual air. No ceria or other non-garnet phases were detected. Cerium 3 + ions substituted on the yttrium sites and no cerium 4 + ions were found. The Faraday rotation angle of the MPC was -2.92° at a wavelength of λ = 1570 nm was 30 times larger than that of the CeYIG film. These results showed good agreement with calculated values derived using a matrix approach.

  9. Aluminum Nanoholes for Optical Biosensing

    Directory of Open Access Journals (Sweden)

    Carlos Angulo Barrios

    2015-07-01

    Full Text Available Sub-wavelength diameter holes in thin metal layers can exhibit remarkable optical features that make them highly suitable for (biosensing applications. Either as efficient light scattering centers for surface plasmon excitation or metal-clad optical waveguides, they are able to form strongly localized optical fields that can effectively interact with biomolecules and/or nanoparticles on the nanoscale. As the metal of choice, aluminum exhibits good optical and electrical properties, is easy to manufacture and process and, unlike gold and silver, its low cost makes it very promising for commercial applications. However, aluminum has been scarcely used for biosensing purposes due to corrosion and pitting issues. In this short review, we show our recent achievements on aluminum nanohole platforms for (biosensing. These include a method to circumvent aluminum degradation—which has been successfully applied to the demonstration of aluminum nanohole array (NHA immunosensors based on both, glass and polycarbonate compact discs supports—the use of aluminum nanoholes operating as optical waveguides for synthesizing submicron-sized molecularly imprinted polymers by local photopolymerization, and a technique for fabricating transferable aluminum NHAs onto flexible pressure-sensitive adhesive tapes, which could facilitate the development of a wearable technology based on aluminum NHAs.

  10. Ballistic Evaluation of 2060 Aluminum

    Science.gov (United States)

    2016-05-24

    experiments in Experimental Facilities (EFs) 108 and 106, as well as John Hogan of ARL/AMB, Hugh Walter of Bowhead Science and Technology, and David Handshoe...new aluminum (Al)-based monocoque armored-vehicle hulls such as those of the M2 Bradley Infantry Fighting Vehicles. Also in 2012 the Aluminum

  11. Wettability of Aluminum on Alumina

    Science.gov (United States)

    Bao, Sarina; Tang, Kai; Kvithyld, Anne; Tangstad, Merete; Engh, Thorvald Abel

    2011-12-01

    The wettability of molten aluminum on solid alumina substrate has been investigated by the sessile drop technique in a 10-8 bar vacuum or under argon atmosphere in the temperature range from 1273 K to 1673 K (1000 °C to 1400 °C). It is shown that the reduction of oxide skin on molten aluminum is slow under normal pressures even with ultralow oxygen potential, but it is enhanced in high vacuum. To describe the wetting behavior of the Al-Al2O3 system at lower temperatures, a semiempirical calculation was employed. The calculated contact angle at 973 K (700 °C) is approximately 97 deg, which indicates that aluminum does not wet alumina at aluminum casting temperatures. Thus, a priming height is required for aluminum to infiltrate a filter. Wetting in the Al-Al2O3 system increases with temperature.

  12. Hualu Aluminum Will Construct Large Coal-Power-Aluminum Aluminum Processing Industrial Chain

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    The reporter learned from relevant departments of Baiyin City that in order to further push forward industrial upgrading,fulfill expansion and consolidation of the enterprise,Gansu Hualu Aluminum Co.,Ltd(Hualu Aluminum)will implement Out-Of-City-Into-Park project,

  13. Selection of crucible oxides in molten titanium and titanium aluminum alloys by thermo-chemistry calculations

    Directory of Open Access Journals (Sweden)

    Kostov A.

    2005-01-01

    Full Text Available Titanium and its alloys interstitially dissolve a large amount of impurities such as oxygen and nitrogen, which degrade the mechanical and physical properties of alloys. On the other hand crucible oxides based on CaO, ZrO2 Y2O3, etc., and their spinels (combination of two or more oxides can be used for melting titanium and its alloys. However, the thermodynamic behavior of calcium, zirconium, yttrium on the one side, and oxygen on the other side, in molten Ti and Ti-Al alloys have not been made clear and because of that, it is very interesting for research. Owing of literature data, as well as these crucibles are cheaper than standard crucibles for melting titanium and titanium alloys, in this paper will be presented the results of selection of thermo-chemistry analysis with the aim to determine the crucible oxide stability in contact with molten titanium and titanium-aluminum alloys.

  14. Application of diffusion barriers to the refractory fibers of tungsten, columbium, carbon and aluminum oxide

    Science.gov (United States)

    Douglas, F. C.; Paradis, E. L.; Veltri, R. D.

    1973-01-01

    A radio frequency powered ion-plating system was used to plate protective layers of refractory oxides and carbide onto high strength fiber substrates. Subsequent overplating of these combinations with nickel and titanium was made to determine the effectiveness of such barrier layers in preventing diffusion of the overcoat metal into the fibers with consequent loss of fiber strength. Four substrates, five coatings, and two metal matrix materials were employed for a total of forty material combinations. The substrates were tungsten, niobium, NASA-Hough carbon, and Tyco sapphire. The diffusion-barrier coatings were aluminum oxide, yttrium oxide, titanium carbide, tungsten carbide with 14% cobalt addition, and zirconium carbide. The metal matrix materials were IN 600 nickel and Ti 6/4 titanium. Adhesion of the coatings to all substrates was good except for the NASA-Hough carbon, where flaking off of the oxide coatings in particular was observed.

  15. Effect of yttrium addition on water-gas shift reaction over CuO/CeO2 catalysts

    Institute of Scientific and Technical Information of China (English)

    SHE Yusheng; LI Lei; ZHAN Yingying; LIN Xingyi; ZHENG Qi; WEI Kemei

    2009-01-01

    This paper presented a study on the role of yttrium addition to CuO/CeO2 catalyst for water-gas shift reaction. A single-step co-precipitation method was used for preparation of a series of yttrium doped CuO/CeO2 catalysts with yttrium content in the range of 0-5wt.%. Properties of the obtained samples were characterized and analyzed by X-ray diffraction (XRD), Raman spectroscopy, H2-TPR, cyclic voltammetry (CV) and the BET method. The results revealed that catalytic activity was increased with the yttrium content at first, but then decreased with the further increase of yttrium content. Herein, CuO/CeO2 catalyst doped with 2wt.% of yttrium showed the highest catalytic activity (CO conversion reaches 93.4% at 250℃) and thermal stability for WGS reaction. The catalytic activity was correlated with the surface area, the area of peak y of H2-TPR profile (I.e., the reduction of surface copper oxide (crystalline forms) interacted with surface oxygen vacancies on ceria), and the area of peak C2 and A1 (Cu0→Cu2+ in cyclic voltammetry process), respectively. Besides, Raman spectra provided evidences for a synergistic Cu-Ovacancy interaction, and it was indicated that doping yttrium may facilitate the formation of oxygen vacancies on ceria.

  16. Growth and hydrogenation of epitaxial yttrium switchable mirrors on CaF2

    NARCIS (Netherlands)

    Kooij, E.S.; Rector, J.H.; Nagengast, D.G.; Kerssemakers, J.W.J.; Dam, B.; Griessen, R.; Remhof, A.; Zabel, H.

    2002-01-01

    Rutherford backscattering (RBS) ion channeling measurements and X-ray diffraction experiments are performed to study the epitaxial nature of as-deposited yttrium on CaF2111 substrates and the effect of hydrogenation on the crystalline quality. The RBS and X-ray results clearly demonstrate the unique

  17. Controlled synthesis and formation mechanism of sodium yttrium fluoride nanotube arrays

    Institute of Scientific and Technical Information of China (English)

    TIAN Li; TAN Li; SUN Qiliang; XIANG Shaobin; XIAO Qiuguo; TANG Jianting; ZHU Guangshan

    2012-01-01

    Cubic and hexagonal sodium yttrium fluoride were successfully synthesized from yttrium nitrate,sodium fluoride and polyethanediol in propanetriol solvent under a facile hydrothermal route.By regulating the molar ratio of yttrium and fluoride,hydrothermal temperature and reaction time,the phase and shape of sodium yttrium fluoride were commendably controlled.The as-prepared products were characterized by X-ray diffraction (XRD),scanning electron microscopy (SEM) and energy dispersive X-ray spectrum (EDS) techniques.It was revealed that the hollow-structured Na(Y1.5Na0.5)F6 nanotubes self-assembled and arrayed orientedly to be bamboo raft-shaped.The formation of hexagonal Na(Y1.5Na0.5)F6 nanotube arrays was attributed to solid-liquid-solid process and Oswald ripening.This study provided a simple method to prepare hexagonal bamboo raft-shaped Na(Y1.5Na0.5)F6 on a large scale,which broadened their practical applications.

  18. Yttrium recovery from primary and secondary sources: A review of main hydrometallurgical processes

    Energy Technology Data Exchange (ETDEWEB)

    Innocenzi, Valentina, E-mail: valentina.innocenzi1@univaq.it [Department of Industrial Engineering, of Information and Economy, University of L’Aquila, Via Giovanni Gronchi 18, Zona industriale di Pile, 67100 L’Aquila (Italy); De Michelis, Ida [Department of Industrial Engineering, of Information and Economy, University of L’Aquila, Via Giovanni Gronchi 18, Zona industriale di Pile, 67100 L’Aquila (Italy); Kopacek, Bernd [SAT, Austrian Society for Systems Engineering and Automation, Gurkasse 43/2, A-1140 Vienna (Austria); Vegliò, Francesco [Department of Industrial Engineering, of Information and Economy, University of L’Aquila, Via Giovanni Gronchi 18, Zona industriale di Pile, 67100 L’Aquila (Italy)

    2014-07-15

    Highlights: • Review of the main hydrometallurgical processes to recover yttrium. • Recovery of yttrium from primary sources. • Recovery of yttrium from e-waste and other types of waste. - Abstract: Yttrium is important rare earths (REs) used in numerous fields, mainly in the phosphor powders for low-energy lighting. The uses of these elements, especially for high-tech products are increased in recent years and combined with the scarcity of the resources and the environmental impact of the technologies to extract them from ores make the recycling waste, that contain Y and other RE, a priority. The present review summarized the main hydrometallurgical technologies to extract Y from ores, contaminated solutions, WEEE and generic wastes. Before to discuss the works about the treatment of wastes, the processes to retrieval Y from ores are discussed, since the processes are similar and derived from those already developed for the extraction from primary sources. Particular attention was given to the recovery of Y from WEEE because the recycle of them is important not only for economical point of view, considering its value, but also for environmental impact that this could be generated if not properly disposal.

  19. Sol-Gel Synthesis and Antioxidant Properties of Yttrium Oxide Nanocrystallites Incorporating P-123

    Directory of Open Access Journals (Sweden)

    Rebeca Mellado-Vázquez

    2014-09-01

    Full Text Available Yttrium oxide (Y2O3 nanocrystallites were synthesized by mean of a sol-gel method using two different precursors. Raw materials used were yttrium nitrate and yttrium chloride, in methanol. In order to promote oxygen vacancies, P-123 poloxamer was incorporated. Synthesized systems were heat-treated at temperatures from 700 °C to 900 °C. Systems at 900 °C were prepared in the presence and absence of P-123 using different molar ratios (P-123:Y = 1:1 and 2:1. Fourier transform infrared spectroscopy (FTIR results revealed a characteristic absorption band of Y–O vibrations typical of Y2O3 matrix. The structural phase was analyzed by X-ray diffraction (XRD, showing the characteristic cubic phase in all systems. The diffraction peak that presented the major intensity corresponded to the sample prepared from yttrium chloride incorporating P-123 in a molar ratio of P-123:Y = 2:1 at 900 °C. Crystallites sizes were determined by Scherrer equation as between 21 nm and 32 nm. Antioxidant properties were estimated by 2,2-diphenyl-1-picrylhydrazyl (DPPH• assays; the results are discussed.

  20. Spray Rolling Aluminum Strip

    Energy Technology Data Exchange (ETDEWEB)

    Lavernia, E.J.; Delplanque, J-P; McHugh, K.M.

    2006-05-10

    Spray forming is a competitive low-cost alternative to ingot metallurgy for manufacturing ferrous and non-ferrous alloy shapes. It produces materials with a reduced number of processing steps, while maintaining materials properties, with the possibility of near-net-shape manufacturing. However, there are several hurdles to large-scale commercial adoption of spray forming: 1) ensuring strip is consistently flat, 2) eliminating porosity, particularly at the deposit/substrate interface, and 3) improving material yield. Through this program, a new strip/sheet casting process, termed spray rolling, has been developed, which is an innovative manufacturing technique to produce aluminum net-shape products. Spray rolling combines the benefits of twin-roll casting and conventional spray forming, showing a promising potential to overcome the above hurdles associated with spray forming. Spray rolling requires less energy and generates less scrap than conventional processes and, consequently, enables the development of materials with lower environmental impacts in both processing and final products. Spray Rolling was developed as a collaborative project between the University of California-Davis, the Colorado School of Mines, the Idaho National Engineering and Environmental Laboratory, and an industry team. The following objectives of this project were achieved: (1) Demonstration of the feasibility of the spray rolling process at the bench-scale level and evaluation of the materials properties of spray rolled aluminum strip alloys; and (2) Demonstration of 2X scalability of the process and documentation of technical hurdles to further scale up and initiate technology transfer to industry for eventual commercialization of the process.

  1. Subsurface Aluminum Nitride Formation in Iron-Aluminum Alloys

    Science.gov (United States)

    Bott, June H.

    Transformation-induced plasticity (TRIP) steels containing higher amounts of aluminum than conventional steels are ideal for structural automotive parts due to their mechanical properties. However, the aluminum tends to react with any processing environment at high temperatures and therefore presents significant challenges during manufacturing. One such challenge occurs during secondary cooling, reheating, and hot-rolling and is caused by a reaction with nitrogen-rich atmospheres wherein subsurface aluminum nitride forms in addition to internal and external oxides. The nitrides are detrimental to mechanical properties and cause surface cracks. It is important to understand how these nitrides and oxides form and their consequences for the quality of steel products. This study looks at model iron-aluminum (up to 8 wt.% aluminum) alloys and uses confocal laser scanning microscopy, x-ray diffraction, scanning electron microscopy with energy dispersive x-ray spectrometry, and transmission electron microscopy to study the effect of various conditions on the growth and development of these precipitates in a subsurface oxygen-depleted region. By using model alloys and controlling the experimental atmosphere, this study is able to understand some of the more fundamental materials science behind aluminum nitride formation in aluminum-rich iron alloys and the relationship between internal nitride and oxide precipitation and external oxide scale morphology and composition. The iron-aluminum alloys were heated in N2 atmospheres containing oxygen impurities. It was found that nitrides formed when bulk aluminum content was below 8 wt.% when oxygen was sufficiently depleted due to the internal oxidation. In the samples containing 1 wt.% aluminum, the depth of the internal oxide and nitride zones were in agreement with a diffusion-based model. Increasing aluminum content to 3 and 5 wt% had the effects of modifying the surface-oxide scale composition and increasing its continuity

  2. The effects of yttrium on the hydrogenation performance and surface properties of a ruthenium-supported catalyst

    Directory of Open Access Journals (Sweden)

    LAITAO LUO

    2005-12-01

    Full Text Available The effects of yttrium on the hydrogenation performance and surface properties of a Ru/sepiolite catalyst were studied. With CO2 methanation and CS2 poisoning as the testing reactons, TPR, TPD, XRD and CO chemisorption as the characterizations, the results showed that the presence of yttrium can increase the hydrogenation activity and anti-poisoning capacity of the Ru/sepiolite catalyst, which is due to a change of surface properties of the Ru/sepiolite. In the process of the catalytic reaction, the adjusting behavior of yttrium for the Ru/sepiolite catalyst aids in increasing the catalytic activity and anti-poisoning capacity of the catalyst.

  3. Yttrium (III chloride catalyzed Mannich reaction: An efficient procedure for the synthesis of β-amino carbonyl compounds

    Directory of Open Access Journals (Sweden)

    Venkateswarlu Yekkirala

    2014-12-01

    Full Text Available Yttrium (III chloride catalyzed Mannich reaction of aldehydes with ketones and amines in acetonitrile at reflux temperature to give various β-amino carbonyl compounds in very good yields.

  4. Invisible Display in Aluminum

    DEFF Research Database (Denmark)

    Prichystal, Jan Phuklin; Hansen, Hans Nørgaard; Bladt, Henrik Henriksen

    2005-01-01

    Bang & Olufsen a/s has been working with ideas for invisible integration of displays in metal surfaces. Invisible integration of information displays traditionally has been possible by placing displays behind transparent or semitransparent materials such as plastic or glass. The wish for an integ...... be obtained by shining light from the backside of the workpiece. When there is no light from the backside, the front surface seems totally untouched. This was achieved by laser ablation with ultra-short pulses.......Bang & Olufsen a/s has been working with ideas for invisible integration of displays in metal surfaces. Invisible integration of information displays traditionally has been possible by placing displays behind transparent or semitransparent materials such as plastic or glass. The wish...... for an integrated display in a metal surface is often ruled by design and functionality of a product. The integration of displays in metal surfaces requires metal removal in order to clear the area of the display to some extent. The idea behind an invisible display in Aluminum concerns the processing of a metal...

  5. Anodized aluminum on LDEF

    Science.gov (United States)

    Golden, Johnny L.

    1993-01-01

    A compilation of reported analyses and results obtained for anodized aluminum flown on the Long Duration Exposure Facility (LDEF) was prepared. Chromic acid, sulfuric acid, and dyed sulfuric acid anodized surfaces were exposed to the space environment. The vast majority of the anodized surface on LDEF was chromic acid anodize because of its selection as a thermal control coating for use on the spacecraft primary structure, trays, tray clamps, and space end thermal covers. Reports indicate that the chromic acid anodize was stable in solar absorptance and thermal emittance, but that contamination effects caused increases in absorptance on surfaces exposed to low atomic oxygen fluences. There were some discrepancies, however, in that some chromic acid anodized specimens exhibited significant increases in absorptance. Sulfuric acid anodized surfaces also appeared stable, although very little surface area was available for evaluation. One type of dyed sulfuric acid anodize was assessed as an optical baffle coating and was observed to have improved infrared absorptance characteristics with exposure on LDEF.

  6. Gas evolution behavior of aluminum in mortar

    Energy Technology Data Exchange (ETDEWEB)

    Hashizume, Shuji; Matsumoto, Junko; Banba, Tsunetaka [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1996-10-01

    As a part of study of leaching behavior for solidified dry low level radioactive waste, gas evolution behavior of aluminum in mortar was investigated, and a plan of our research was proposed. The effect of pH on corrosion rate of aluminum, corrosion product, time dependency of corrosion rate of aluminum in mortar, change of corrosion mechanism, the effects of Na, Ca and Cl ions on corrosion rate of aluminum in mortar and corrosion behavior of aluminum when aluminum was used as sacrificed anode in reinforced concrete were previously clarified. Study of the effects of environmental factors such as pH, kind of ions and temperature on gas evolution behavior of aluminum and the effect of aluminum/carbon steel surface ratio no gas evolution behavior of aluminum were planed. (author). 75 refs.

  7. Yttrium and lanthanum recovery from low cerium carbonate, yttrium carbonate and yttrium concentrate; Aproveitamento de itrio e lantanio de um carbonato de terras raras de baixo teor em cerio, de um carbonato de itrio e de um oxido de terras itricas

    Energy Technology Data Exchange (ETDEWEB)

    Vasconcelos, Mari Estela de

    2006-07-01

    In this work, separation, enrichment and purification of lanthanum and yttrium were performed using as raw material a commercial low cerium rare earth concentrate named LCC (low cerium carbonate), an yttrium concentrate named 'yttrium carbonate', and a third concentrated known as 'yttrium earths oxide. The first two were industrially produced by the late NUCLEMON - NUCLEBRAS de Monazita e Associados Ltda, using Brazilian monazite. The 'yttrium earths oxide' come from a process for preparation of lanthanum during the course of the experimental work for the present thesis. The following techniques were used: fractional precipitation with urea; fractional leaching of the LCC using ammonium carbonate; precipitation of rare earth peroxycarbonates starting from the rare earth complex carbonates. Once prepared the enriched rare earth fractions the same were refined using the ion exchange chromatography with strong cationic resin without the use of retention ion and elution using the ammonium salt of ethylenediaminetetraacetic acid. With the association of the above mentioned techniques were obtained pure oxides of yttrium (>97,7%), lanthanum (99,9%), gadolinium (96,6%) and samarium (99,9%). The process here developed has technical and economic viability for the installation of a large scale unity. (author)

  8. Demonstrating the potential of yttrium-doped barium zirconate electrolyte for high-performance fuel cells

    Science.gov (United States)

    Bae, Kiho; Jang, Dong Young; Choi, Hyung Jong; Kim, Donghwan; Hong, Jongsup; Kim, Byung-Kook; Lee, Jong-Ho; Son, Ji-Won; Shim, Joon Hyung

    2017-02-01

    In reducing the high operating temperatures (>=800 °C) of solid-oxide fuel cells, use of protonic ceramics as an alternative electrolyte material is attractive due to their high conductivity and low activation energy in a low-temperature regime (fuel cells. However, poor sinterability of yttrium-doped barium zirconate discourages its fabrication as a thin-film electrolyte and integration on porous anode supports, both of which are essential to achieve high performance. Here we fabricate a protonic-ceramic fuel cell using a thin-film-deposited yttrium-doped barium zirconate electrolyte with no impeding grain boundaries owing to the columnar structure tightly integrated with nanogranular cathode and nanoporous anode supports, which to the best of our knowledge exhibits a record high-power output of up to an order of magnitude higher than those of other reported barium zirconate-based fuel cells.

  9. A yttrium-containing high-temperature titanium alloy additively manufactured by selective electron beam melting

    Institute of Scientific and Technical Information of China (English)

    逯圣路; 汤慧萍; 马前; 洪权; 曾立英

    2015-01-01

    A yttrium-containing high-temperature titanium alloy (Ti-6Al-2.7Sn-4Zr-0.4Mo-0.45Si-0.1Y, mass fraction, %) has been additively manufactured using selective electron beam melting (SEBM). The resulting microstructure and textures were studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and electron backscattered diffraction (EBSD) and compared with the conventionally manufactured form. A notable distinct difference of microstructures is that additive manufacturing by SEBM enables homogeneous precipitation of fine Y2O3 dispersoids in the size range of 50−250 nm throughout the as-fabricated alloy, despite the presence of just trace levels of oxygen (7×10−4, mass fraction) and yttrium (10−3, mass fraction) in the alloy. In contrast, the conventionally manufactured alloy shows inhomogeneously distributed coarse Y2O3 precipitates, including cracked or debonded Y2O3 particles.

  10. Effect of sintering on electrical properties of yttrium doped Li-based NASICON compounds

    Energy Technology Data Exchange (ETDEWEB)

    Kothari, Dharmesh H.; Kanchan, D. K., E-mail: dkkanchan.ssi@gmail.com; Dave, Gargi [Solid State Ionics & Glass Research Laboratory, Department of Physics, Faculty of Science, The M. S. University of Baroda, Vadodara, Gujarat-390002 (India)

    2015-08-28

    Electrical properties of Lithium based Li{sub 1.3}Al{sub 0.3-x}Y{sub x}Ti{sub 1.7}(PO{sub 4}){sub 3} (LAYTP) system was prepared using solid state reaction route. The samples were subjected to differing duration of sintering. X-ray diffraction was used to investigate the microstructure while density measurement was performed to determine the effect of sintering on the density of the prepared samples. Electrical properties of the material were studied using impedance spectroscopy, in frequency range 20 MHz to 1 Hz and in temperature range 303 K to 423 K. It was found that sample with least amount of yttrium and which was sintered for least duration had superior conductivity over other samples. It was also found that grain boundary conductivity improved marginally for sample with higher proportion of yttrium heat treated for longer duration.

  11. Co-sputtering yttrium into hafnium oxide thin films to produce ferroelectric properties

    Science.gov (United States)

    Olsen, T.; Schröder, U.; Müller, S.; Krause, A.; Martin, D.; Singh, A.; Müller, J.; Geidel, M.; Mikolajick, T.

    2012-08-01

    Thin film capacitors were fabricated by sputtering TiN-Y doped HfO2-TiN stacks on silicon substrates. Yttrium was incorporated into the HfO2 layers by simultaneously sputtering from Y2O3 and HfO2 sources. Electric polarization and relative permittivity measurements yield distinct ferroelectric properties as a result of low yttrium dopant concentrations in the range of 0.9-1.9 mol. %. Grazing incidence x-ray diffraction measurements show the formation of an orthorhombic phase in this range. Compared to atomic layer deposition films, the highest remanent polarization and the highest relative permittivity were obtained at significantly lower doping concentrations in these sputtered films.

  12. Preparation and Characterization of Porous Yttrium Oxide Powders with High Specific Surface Area

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The porous cubic yttrium oxides with high specific surface area were prepared by the explosive decomposition of yttrium nitrate and its complex formed with methyl salicylate. The specific surface area and properties of powders synthesized at various temperatures were characterized using BET, X-ray diffraction (XRD), infrared spectra (IR), and scanning electron microscopy (SEM). The results indicate that the highest specific surface area is found to be 65.37 m2*g-1 at the calcination temperature of 600 ℃, and then decreases to 20.33 m2*g-1 with the calcination temperature rising from 600 to 900 ℃. The powders show strong surface activity for adsorping water and carbon dioxide in air, which also decreases with the rising calcination temperature. The drop both on the surface area and surface activity of samples at higher temperatures may be due to pore-narrowing(sintering) effects.

  13. Effect of Yttrium on Microstructure and Properties of High Temperature Alloys

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The effect of yttrium on the microstructure and properties of Ti-5.5Al-3.5Sn-3.0Zr-1Nb-0.3Mo-0.3Si (IMI 829) and Ti-14Al-21Nb high temperature alloys was studied by using optical microscope, SEM and mechanical property testing devices. The results show that the microstructure and grains of the two alloys can be fined by adding yttrium. For IMI829-0.2Y alloy, the favorable mechanical properties at room temperature and creep properties at 550℃ are obtained, and the high temperature mechanical properties of Ti-14Al-21Nb-0.1Y alloy are improved as well.

  14. First principles DFT investigation of yttrium-doped graphene: Electronic structure and hydrogen storage

    Energy Technology Data Exchange (ETDEWEB)

    Desnavi, Sameerah, E-mail: sameerah-desnavi@zhcet.ac.in [Department of Electronic Engineering, ZHCET, Aligarh Muslim University, Aligarh-202002 (India); Chakraborty, Brahmananda; Ramaniah, Lavanya M. [High Pressure and Synchrotron Radiation Physics Division, Bhabha Atomic Research Centre, Mumbai-400085 (India)

    2014-04-24

    The electronic structure and hydrogen storage capability of Yttrium-doped grapheme has been theoretically investigated using first principles density functional theory (DFT). Yttrium atom prefers the hollow site of the hexagonal ring with a binding energy of 1.40 eV. Doping by Y makes the system metallic and magnetic with a magnetic moment of 2.11 μ{sub B}. Y decorated graphene can adsorb up to four hydrogen molecules with an average binding energy of 0.415 eV. All the hydrogen atoms are physisorbed with an average desorption temperature of 530.44 K. The Y atoms can be placed only in alternate hexagons, which imply a wt% of 6.17, close to the DoE criterion for hydrogen storage materials. Thus, this system is potential hydrogen storage medium with 100% recycling capability.

  15. Scaleable Clean Aluminum Melting Systems

    Energy Technology Data Exchange (ETDEWEB)

    Han, Q.; Das, S.K. (Secat, Inc.)

    2008-02-15

    The project entitled 'Scaleable Clean Aluminum Melting Systems' was a Cooperative Research and Development Agreements (CRADAs) between Oak Ridge National Laboratory (ORNL) and Secat Inc. The three-year project was initially funded for the first year and was then canceled due to funding cuts at the DOE headquarters. The limited funds allowed the research team to visit industrial sites and investigate the status of using immersion heaters for aluminum melting applications. Primary concepts were proposed on the design of furnaces using immersion heaters for melting. The proposed project can continue if the funding agency resumes the funds to this research. The objective of this project was to develop and demonstrate integrated, retrofitable technologies for clean melting systems for aluminum in both the Metal Casting and integrated aluminum processing industries. The scope focused on immersion heating coupled with metal circulation systems that provide significant opportunity for energy savings as well as reduction of melt loss in the form of dross. The project aimed at the development and integration of technologies that would enable significant reduction in the energy consumption and environmental impacts of melting aluminum through substitution of immersion heating for the conventional radiant burner methods used in reverberatory furnaces. Specifically, the program would couple heater improvements with furnace modeling that would enable cost-effective retrofits to a range of existing furnace sizes, reducing the economic barrier to application.

  16. Nano metric particles of yttrium ferrite; Particulas nanometricas de ferritas de itrio

    Energy Technology Data Exchange (ETDEWEB)

    Godoi, Ricardo H.M.; Jafelicci Junior, Miguel; Marques, Rodrigo F.C.; Varanda, Laudemir C. [UNESP, Araraquara, SP (Brazil). Inst. de Quimica. Dept. de Fisico-Quimica; Lima, Roberto C. [Instituto de Pesquisas da Marinha, Rio de Janeiro, RJ (Brazil)

    1999-12-01

    Nanoparticles of yttrium iron garnet (YIG) were obtained by coprecipitation. The particles were prepared by hydrolysis in acid medium with addition of ammonia or urea, for homogeneous nucleation, at 90 deg C. Different compositions and spherical morphologies were achieved by changing reactants concentrations and precipitation agent. X-ray diffractometry, transmission electron microscopy, differential thermal analysis and electrophoretic mobility were carried out on these particles to investigate the obtained phase, phase transition temperature, morphology, particle size and zeta potential, respectively. (author)

  17. Peripheral Blood Lymphocyte Depletion After Hepatic Arterial {sup 90}Yttrium Microsphere Therapy for Hepatocellular Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Carr, Brian I., E-mail: brianicarr@hotmail.com [Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA and Department of Nutrition and Exptl Biology, Saverio De Bellis Medical Research Institute, Castellana Grotte, Bari (Italy); Metes, Diana M. [Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA and Department of Nutrition and Exptl Biology, Saverio De Bellis Medical Research Institute, Castellana Grotte, Bari (Italy)

    2012-03-01

    Purpose: The short- and long-term effects of {sup 90}Yttrium microspheres therapy for hepatocellular carcinoma (HCC) on peripheral blood lymphocytes are unknown and were therefore examined. Methods and Materials: Ninety-two HCC patients were enrolled in a {sup 90}Yttrium therapy study and routine blood counts were examined as part of standard clinical monitoring. Results: We found an early, profound, and prolonged lymphopenia. In a subsequent cohort of 25 additional HCC patients, prospective flow cytometric immune-monitoring analysis was performed to identify specific changes on distinct lymphocyte subsets (i.e., CD3, CD4, CD8 T, and CD19 B lymphocytes) and NK cells absolute numbers, in addition to the granulocytes and platelets subsets. We found that the pretreatment lymphocyte subset absolute numbers (with the exception of NK cells) had a tendency to be lower compared with healthy control values, but no significant differences were detected between groups. Posttherapy follow-up revealed that overall, all lymphocyte subsets, except for NK cells, were significantly (>50% from pretherapy values), promptly (as early as 24 h) and persistently (up to 30 months) depleted post-{sup 90}Yttrium microspheres therapy. In contrast, granulocytes increased rapidly (24 h) to compensate for lymphocyte depletion, and remained increased at 1-year after therapy. We further stratified patients into two groups, according to survival at 1 year. We found that lack of recovery of CD19, CD3, CD8, and especially CD4 T cells was linked to poor patient survival. No fungal or bacterial infections were noted during the 30-month follow-up period. Conclusions: The results show that lymphocytes (and not granulocytes, platelets, or NK cells) are sensitive to hepatic arterial {sup 90}Yttrium without associated clinical toxicity, and lack of lymphocyte recovery (possibly leading to dysregulation of adaptive cellular immunity) posttherapy indicates poor survival.

  18. Yttrium-90 Radioembolization of Hepatocellular Carcinoma-Performance, Technical Advances, and Future Concepts.

    Science.gov (United States)

    Molvar, Christopher; Lewandowski, Robert

    2015-12-01

    Hepatocellular carcinoma (HCC) is a lethal tumor, claiming over half a million lives per year. Treatment of HCC is commonly performed without curative intent, and palliative options dominate, including catheter-based therapies, namely, transarterial chemoembolization and yttrium-90 ((90)Y) radioembolization. This review will showcase the performance of (90)Y radioembolization for the treatment of HCC, focusing on recent seminal data and technical advances. In particular, novel radioembolization treatment concepts are discussed and compared with conventional HCC therapy.

  19. The effect of yttrium substitution on the magnetic properties of magnetite nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Mozaffari, M., E-mail: mozafari@sci.ui.ac.ir; Amighian, J.; Tavakoli, R.

    2015-04-01

    Superparamagnetic Y-substituted magnetite (Y{sub x}Fe{sub 3–x}O{sub 4},with x=0.00, 0.10, 0.15, 0.20 and 0.40) nanoparticles were synthesized via hydrothermal reduction route in the presence of citric acid. The synthesized nanoparticles were characterized by X-ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), vibrating sample magnetometry (VSM) and gradient field thermomagnetic measurement. The results showed that a minimum amount of citric acid is required to obtain single phase Y-substituted magnetite nanoparticles. Citric acid acts as a modulator and reducing agent in the formation of spinel structure and controls nanoparticle size and crystallinity. Mean crystallite sizes of the single-phase powders were estimated by Williamson–Hall method. Curie temperature measurement of the samples shows that as yttrium content increases, the Curie temperature decreases. Magnetic measurements show that the saturation magnetization of the samples decreases as x increases up to 0.15 and then increases to x=0.20 and finally decreases again for x=0.40. - Highlights: • Single phase yttrium substituted magnetite nanoparticles were synthesized by hydrothermal-reduction route. • Citric acid plays a key role in reduction of Fe{sup 3+} to Fe{sup 2+}, which is necessary for the formation of magnetite phase. • It is possible to substitute yttrium ions for iron ones as high as x=0.4 by hydrothermal reduction route. • Pure magnetite nanoparticles prepared by this route has a high saturation magnetization. • Yttrium substituted magnetite nanoparticles are superparamagnet at room temperature.

  20. Effects of minor yttrium addition on hot deformability of lamellar Ti-45Al-5Nb alloy

    Institute of Scientific and Technical Information of China (English)

    CHEN Yu-yong; LI Bao-hui; KONG Fan-tao

    2007-01-01

    The effects of 0.3%(molar fraction, the same below) yttrium addition on hot deformability of lamellar Ti-45Al-5Nb alloy were investigated by simulated isothermal forging tests. The ingots with the nominal compositions of Ti-45Al-5Nb and Ti-45Al-5Nb-0.3Y were prepared by induction skull melting. Simulated isothermal forging tests were conducted on Gleeble 1500D thermo-simulation machine using a 6 mm in diameter and 10 mm in length compressive specimen at the deformation temperatures of 1 100, 1 150, 1 200 ℃ and strain rates of 1.0, 0.1, 0.01 s-1. The results show that yttrium addition remarkably improves hot deformability of Ti-45Al-5Nb alloy. An appropriate hot deformation processing parameter of Ti-45Al-5Nb-0.3Y alloy is determined as 1 200 ℃, 0.01 s-1. The flow stresses are decreased by yttrium addition under the same compressive conditions. The activation energies of deformation Q are calculated as 448.6 and 399.5 kJ/mol for Y-free and Y-containing alloys, respectively. The deformed microstructure observation under 1 200 ℃, 0.01 s-1 condition indicates that Ti-45Al-5Nb-0.3Y alloy shows more dynamic recrystallization. The improvement of hot deformability of Ti-45Al-5Nb-0.3Y alloy induced by yttrium addition should be attributed to that the smaller the original lamellar colonies, the lower the deformation resistance and activation energy of deformation are, and the more the dynamic recrystallization is.

  1. Yttrium deposition on mesoporous TiO2: textural design and UV decolourization of organic dyes

    Indian Academy of Sciences (India)

    M L Ojeda; C Velasquez; V Renteria; A Campero; M A García-Sánchez; F Rojas

    2015-02-01

    This study discusses about the photochemical, topological and textural properties of yttrium-doped titanium dioxide (TiO2) photocatalysts. The mesoporous yttrium-doped TiO2 substrates prepared in this research work operate efficiently via low-cost commercial 13-W UV lamps. A quantity of 2 wt% yttrium deposition on TiO2 accelerates methyl orange UV decolourization kinetics. When Y content increases to 8 wt%, besides anatase, rutile is formed from 600°C. The Y2Ti2O7 photoinactive compound emerges at 800°C. The P-123 surfactant mesopore templating treatment of TiO2 xerogels (when concurrent with the sol–gel Y-doping of Ti alkoxides) features the following two correlated phenomena: (i) The surface area increases while the access to the inner porosity of the substrate becomes much easier, so that a larger portion of the surface is made accessible to the dye molecules as well as to the yttrium dopant; (ii) the inclusion of tubular instead of ink-bottle pores facilitates the transport of organic species in and out of the pore structure. The most active mesoporous substrate resulted to be made of 2 wt% Y; contrastingly, when Y= 8 wt%, photoinactivity arose because of Y2Ti2O7 formation. The involvement of P123 was not the sole factor influencing the efficiency of TiO2 mesoporous photocatalysts. There were additional key factors, such as the surging of co-ordination and nucleophilic species, during the dye photodegradation process, which were also induced by the presence of Y species on the surface of these substrates.

  2. Extraction of Yttrium (Ⅲ) into [C8mim][PF6] Containing Cyanex 923

    Institute of Scientific and Technical Information of China (English)

    Peng Bo; Sun Xiaoqi; Chen Ji; Ma Jiutong

    2007-01-01

    The extraction of Yttrium (Ⅲ) into [Cnmim] [PF6] (n=4,6,8) containing Cyanex 923 was studied in this paper. The mechanism of this extraction was indicated to be cation exchange. In addition, the extraction process is an endothermic reaction. The RTILs with shorter alkyl chain behave higher extraction efficiency during the extraction, however, which has also more loss to aqueous phase since the cation exchange mechanism.

  3. Engineering of the band gap and optical properties of thin films of yttrium hydride

    Energy Technology Data Exchange (ETDEWEB)

    You, Chang Chuan; Mongstad, Trygve; Maehlen, Jan Petter; Karazhanov, Smagul, E-mail: smagulk@ife.no [Institute for Energy Technology, P.O. Box 40, NO-2027 Kjeller (Norway)

    2014-07-21

    Thin films of oxygen-containing yttrium hydride show photochromic effect at room temperature. In this work, we have studied structural and optical properties of the films deposited at different deposition pressures, discovering the possibility of engineering the optical band gap by variation of the oxygen content. In sum, the transparency of the films and the wavelength range of photons triggering the photochromic effect can be controlled by variation of the deposition pressure.

  4. Observation of spin rectification in Pt/yttrium iron garnet bilayer

    Energy Technology Data Exchange (ETDEWEB)

    Rao, Jinwei; Fan, Xiaolong, E-mail: fanxiaolong@lzu.edu.cn; Zhou, Hengan; Zhao, Xiaobing; Zhao, Jing; Zhang, Fengzhen; Xue, Desheng [The Key Lab for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Ma, Li; Zhou, Shiming [Shanghai Key Laboratory of Special Artificial Microstructure and Technology and Pohl Institute of Solid State Physics and School of Physics Science and Engineering, Tongji University, Shanghai 200092 (China)

    2015-05-07

    We used the ferromagnetic resonance (FMR) to study the dc voltage generation in Pt 20 nm layer deposited on yttrium iron garnet. Although the main contribution to the FMR voltage comes from the inverse spin Hall effect associated with spin pumping, the spin rectification would also contribute the resonance signal via the “new” magnetoresistance effect in Pt layer. Based on a symmetry consideration, we can separate those two effects through angular dependent resonance amplitude.

  5. Synthesis and characterization of branched yttrium hydroxide fluoride microcrystals with hierarchical tubular structure

    Institute of Scientific and Technical Information of China (English)

    TIAN Li; JIANG Wentao; SUN Qiliang; LIU Jin

    2012-01-01

    Hexagonal yttrium hydroxide fluoride microcrystals were prepared by a two-step hydrothermal route using yttrium nitrate,sodium hydroxide and sodium fluoride as raw materials to react in propanetriol solvent.The samples were characterized by powder X-ray diffraction (XRD),energy dispersive spectrum (EDS),scanning electron microscopy (SEM),transmission electron microscopy (TEM),Fourier transform infrared spectroscopy (FT-IR),thermogravimetre and differential-thermogravimetric analysis (TG-DTA),which revealed that Y(OH)2.14F0.86 microcrystals were multi-branched and that the branches of Y(OH)2.14F0.86 microcrystals were composed of hierarchical tubes.This novel multi-branched and intriguing hierarchical tubular structure of yttrium hydroxide fluoride maybe has a potential application in photoelectric crystals.The formation of branched Y(OH)2.14F0.86 microcrystals with hierarchical tubular structure were due to the substitution reaction and Oswald ripening.

  6. Effect of yttrium on the mechanical and magnetostrictive properties of Fe83Ga17 alloy

    Institute of Scientific and Technical Information of China (English)

    李纪恒; 肖锡铭; 袁超; 高学绪; 包小倩

    2015-01-01

    Polycrystalline rod samples of (Fe83Ga17)100–xYx(x=0, 0.16, 0.32, 0.48, 0.64) were prepared by induction melting under ar-gon atmosphere. Effect of yttrium on the mechanical and magnetostrictive properties of Fe83Ga17 alloy was investigated. Small amount of yttrium (0.16 at.%) increased the tensile strength of as-cast Fe83Ga17 alloys to 674 MPa and improved the ductility with elongation of 4.2% at room temperature. The Y2Fe17?xGax (6≤x≤7) phase was formed in the Y-doped Fe83Ga17 alloy since yttrium was hardly dissolved into theα-Fe lattice. Y2(FeGa)17 secondary phase dispersed along the grain boundaries and inside the grains played an important role for the enhancement of mechanical property. The 0.64 at.% Y-doped alloy had magnetostriction of 133 ppm, which was thought to be associated with the alteration of the grain shape and preferential orientation along the axial direction of rods.

  7. Demonstrating the potential of yttrium-doped barium zirconate electrolyte for high-performance fuel cells.

    Science.gov (United States)

    Bae, Kiho; Jang, Dong Young; Choi, Hyung Jong; Kim, Donghwan; Hong, Jongsup; Kim, Byung-Kook; Lee, Jong-Ho; Son, Ji-Won; Shim, Joon Hyung

    2017-02-23

    In reducing the high operating temperatures (≥800 °C) of solid-oxide fuel cells, use of protonic ceramics as an alternative electrolyte material is attractive due to their high conductivity and low activation energy in a low-temperature regime (≤600 °C). Among many protonic ceramics, yttrium-doped barium zirconate has attracted attention due to its excellent chemical stability, which is the main issue in protonic-ceramic fuel cells. However, poor sinterability of yttrium-doped barium zirconate discourages its fabrication as a thin-film electrolyte and integration on porous anode supports, both of which are essential to achieve high performance. Here we fabricate a protonic-ceramic fuel cell using a thin-film-deposited yttrium-doped barium zirconate electrolyte with no impeding grain boundaries owing to the columnar structure tightly integrated with nanogranular cathode and nanoporous anode supports, which to the best of our knowledge exhibits a record high-power output of up to an order of magnitude higher than those of other reported barium zirconate-based fuel cells.

  8. Off-line studies of the laser ionization of yttrium at the IGISOL facility

    CERN Document Server

    Kessler, T; Kudryavtsev, Y; Peräjärvi, K; Popov, A; Ronkanen, P; Sonoda, T; Tordoff, B; Wendt, K D A; Äystö, J

    2007-01-01

    A laser ion source is under development at the IGISOL facility, Jyvaskyla, in order to address deficiencies in the ion guide technique. The key elements of interest are those of a refractory nature, whose isotopes and isomers are widely studied using both laser spectroscopic and high precision mass measurement techniques. Yttrium has been the first element of choice for the new laser ion source. In this work we present a new coupled dye-Ti:Sapphire laser scheme and give a detailed discussion of the results obtained from laser ionization of yttrium atoms produced in an ion guide via joule heating of a filament. The importance of not only gas purity, but indeed the baseline vacuum pressure in the environment outside the ion guide is discussed in light of the fast gas phase chemistry seen in the yttrium system. A single laser shot model is introduced and is compared to the experimental data in order to extract the level of impurities within the gas cell.

  9. Crystal structure and switchable optical properties of yttrium hydride films covered by palladium layer

    Institute of Scientific and Technical Information of China (English)

    张文魁; 甘永平; 杨晓光; 黄辉; 余厉阳

    2003-01-01

    The palladium/yttrium films were prepared using magnetron sputtering technique.The changes of crystal structure,morphology and optical properties of the films during the hydrogen absorption/desorption process were investigated.The results of SEM and AFM analysis show that yttrium films have columnar structure,and the Pd cover layers on the surface of the yttrium films are composed of nanometer-sized Pd particles,which contain a large amount of smaller crystalline grains.During the gas hydrogen absorption/desorption process,YH3 and YH2 hydrides form on the sites of Pd grains contacting with Y grains.Upon hydrogenation,YH3 hydride forms and the switchable optical properties can be observed.The light transparency of the films increases with the increasing of hydrogen loading time and the light wavelength,and the absorption limitation occurs at λ=400 nm.Upon dehydrogenation,YH3 hydride dissociates into YH2 hydride,and the maximum transparency occurs at λ=689 nm.

  10. Decreasing residual aluminum level in drinking water

    Institute of Scientific and Technical Information of China (English)

    王志红; 崔福义

    2004-01-01

    The relativity of coagulant dosage, residual turbidity, temperature, pH etc. with residual aluminum concentration were investigated, and several important conclusions were achieved. Firstly, dosage of alum-coagulant or PAC1 influences residual aluminum concentration greatly. There is an optimal-dosage-to-aluminum, a bit less than the optimal-dosage-to-turbidity. Secondly, it proposes that decreasing residual aluminum concentration can be theoretically divided into two methods, either decreasing (even removing) the concentration of particulate aluminum component, or decreasing dissolved aluminum. In these tests there is an optimal value of residual turbidity of postprecipitation at 7.0 NTU. Thirdly, residual aluminum level will increase while water temperature goes higher. At the last, optimal pH value corresponds a minimum dissolved aluminum at a given turbidity. Data shows the optimal pH value decreases with water temperature's increasing.

  11. 21 CFR 172.310 - Aluminum nicotinate.

    Science.gov (United States)

    2010-04-01

    ... Special Dietary and Nutritional Additives § 172.310 Aluminum nicotinate. Aluminum nicotinate may be safely... additive, expressed as niacin, shall appear on the label of the food additive container or on that of...

  12. Environmental Control over the Primary Aluminum Industry

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    <正> To strengthen environmental control over theprimary aluminum industry,the State Environ-mental Protection Administration of China hasrecently issued a notice addressing the follow-ing points:Strengthening environmental control over theexisting primary aluminum companies

  13. OPTIMIZING AN ALUMINUM EXTRUSION PROCESS

    Directory of Open Access Journals (Sweden)

    Mohammed Ali Hajeeh

    2013-01-01

    Full Text Available Minimizing the amount of scrap generated in an aluminum extrusion process. An optimizing model is constructed in order to select the best cutting patterns of aluminum logs and billets of various sizes and shapes. The model applied to real data obtained from an existing extrusion factory in Kuwait. Results from using the suggested model provided substantial reductions in the amount of scrap generated. Using sound mathematical approaches contribute significantly in reducing waste and savings when compared to the existing non scientific techniques.

  14. The effect of zinc on the aluminum anode of the aluminum-air battery

    Science.gov (United States)

    Tang, Yougen; Lu, Lingbin; Roesky, Herbert W.; Wang, Laiwen; Huang, Baiyun

    Aluminum is an ideal material for batteries, due to its excellent electrochemical performance. Herein, the effect of zinc on the aluminum anode of the aluminum-air battery, as an additive for aluminum alloy and electrolytes, has been studied. The results show that zinc can decrease the anodic polarization, restrain the hydrogen evolution and increase the anodic utilization rate.

  15. Electrochemical Behavior of Aluminum in Nitric Acid

    Institute of Scientific and Technical Information of China (English)

    CHEN; Hui; ZHU; Li-yang; LIN; Ru-shan; TAN; Hong-bin; HE; Hui

    2013-01-01

    Aluminum is one of cladding materials for nuclear fuel,it is important to investigate the electrolytic dissolution of aluminum in nitric acid.The electrochemical impedance spectroscopy,polarization curve and cyclic voltammetry cure of anodic aluminum electrode in nitric acid under various conditions were collected(Fig.1).It turns out,under steady state,the thickness of the passivated film of aluminum

  16. 76 FR 23490 - Aluminum tris (O

    Science.gov (United States)

    2011-04-27

    ... AGENCY 40 CFR Part 180 Aluminum tris (O-ethylphosphonate), Butylate, Chlorethoxyfos, Clethodim, et al..., fosthiazate, propetamphos, and tebufenozide; the fungicide aluminum tris (O-ethylphosphonate); the herbicides.... Also, EPA is revoking the tolerances for aluminum tris (O-ethylphosphonate) on pineapple fodder...

  17. Guangxi Aluminum Giant Made Investment in Changfeng

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    <正>A aluminum processing and supporting project (450,000 tons) of Hefei Guangyin Aluminum Company kicked off in Xiatang Town of Changfeng County recently. It is a project jointly invested by Guangxi Investment Group and Guangxi Baise Guangyin Aluminum in Xiatang Town of Changfeng County.

  18. Luminescent properties of aluminum hydride

    Energy Technology Data Exchange (ETDEWEB)

    Baraban, A.P.; Gabis, I.E.; Dmitriev, V.A. [Saint-Petersburg State University, Department of Physics, Saint-Petersburg 198504 (Russian Federation); Dobrotvorskii, M.A., E-mail: mstislavd@gmail.com [Saint-Petersburg State University, Department of Physics, Saint-Petersburg 198504 (Russian Federation); Kuznetsov, V.G. [Saint-Petersburg State University, Department of Physics, Saint-Petersburg 198504 (Russian Federation); Matveeva, O.P. [National Mineral Resources University, Saint Petersburg 199106 (Russian Federation); Titov, S.A. [Petersburg State University of Railway Transport, Saint-Petersburg 190031 (Russian Federation); Voyt, A.P.; Elets, D.I. [Saint-Petersburg State University, Department of Physics, Saint-Petersburg 198504 (Russian Federation)

    2015-10-15

    We studied cathodoluminescence and photoluminescence of α-AlH{sub 3}– a likely candidate for use as possible hydrogen carrier in hydrogen-fueled vehicles. Luminescence properties of original α-AlH{sub 3} and α-AlH{sub 3} irradiated with ultraviolet were compared. The latter procedure leads to activation of thermal decomposition of α-AlH{sub 3} and thus has a practical implementation. We showed that the original and UV-modified aluminum hydride contain luminescence centers ‐ structural defects of the same type, presumably hydrogen vacancies, characterized by a single set of characteristic bands of radiation. The observed luminescence is the result of radiative intracenter relaxation of the luminescence center (hydrogen vacancy) excited by electrons or photons, and its intensity is defined by the concentration of vacancies, and the area of their possible excitation. UV-activation of the dehydrogenation process of aluminum hydride leads to changes in the spatial distribution of the luminescence centers. For short times of exposure their concentration increases mainly in the surface regions of the crystals. At high exposures, this process extends to the bulk of the aluminum hydride and ends with a decrease in concentration of luminescence centers in the surface region. - Highlights: • Aluminum hydride contains hydrogen vacancies which serve as luminescence centers. • The luminescence is the result of radiative relaxation of excited centers. • Hydride UV-irradiation alters distribution and concentration of luminescence centers.

  19. Aluminum break-point contacts

    NARCIS (Netherlands)

    Heinemann, Martina; Groot, R.A. de

    1997-01-01

    Ab initio molecular dynamics is used to study the contribution of a single Al atom to an aluminum breakpoint contact during the final stages of breaking and the initial stages of the formation of such a contact. A hysteresis effect is found in excellent agreement with experiment and the form of the

  20. Mössbauer Spectral Properties of Yttrium Iron Garnet, Y3Fe5O12, and its Isovalent and Nonisovalent Yttrium-Substituted Solid Solutions

    Energy Technology Data Exchange (ETDEWEB)

    Long, Gary J.; Grandjean, Fernande; Guo, Xiaofeng; Navrotsky, Alexandra; Kukkadapu, Ravi K.

    2016-03-21

    Several high-resolution Mössbauer spectra of yttrium iron garnet, Y3Fe5O12, have been fit as a function of temperature with a new model based on a detailed analysis of the spectral changes that result from a reduction from the cubic Ia–3d space group to the trigonal R–3 space group. These spectral fits, which are all statistically identical, indicate that the magnetic sextet arising from the 16a site in cubic symmetry is subdivided into three sextets arising from the 6f, and the 3d, 3d, and the 1a, 1b, and 2c sites in rhombohedral-axis trigonal symmetry. The 24d site in cubic symmetry is subdivided into four sextets arising from four different 6f sites in R–3 rhombohedral-axis trigonal symmetry, sites that differ only by the angles between the principal axis of the electric field gradient tensor and the magnetic hyperfine field assumed to be parallel with the magnetic easy axis. This analysis, when applied to the potential nuclear waste storage compounds, Y3-xCa0.5xTh0.5xFe5O12 and Y3- xCa0.5xCe0.5xFe5O12, indicates virtually no perturbation of the structural, electronic, and magnetic properties upon substitution of small amounts of calcium(II) and thorium(IV) or cerium(IV) onto the yttrium(III) 24c site as compared with Y3Fe5O12. The observed broadening of the four different 6f sites derived from the 24d site results from the substitution of yttrium(III) by calcium(II) and thorium(IV) or cerium(IV) cations on the next-nearest neighbor 24c site. In contrast, the same analysis, when applied to Y2.8Ce0.2Fe5O12, indicates a local perturbation of the magnetic exchange pathways as a result of the presence of cerium(IV) in the 24c next-nearest neighbor site of the iron(III) 24d site.

  1. Determination of micro yttrium in an ytterbium matrix by inductively coupled plasma atomic emission spectrometry and wavelet transform

    Institute of Scientific and Technical Information of China (English)

    MA Xiaoguo

    2005-01-01

    In the determination of trace yttrium (Y) in an ytterbium (Yb) matrix by inductively coupled plasma atomic emission spectrometry (ICP-AES), the most prominent line of yttrium, Y 371.030 nm line, suffers from strong interference due to an emission line of ytterbium. In this work, a method based on wavelet transform was proposed for the spectral interference correction. Haar wavelet was selected as the mother wavelet. The discrete detail after the third decomposition, D3,was chosen for quantitative analysis based on the consideration of both separation degree and peak height. The linear correlation coefficient between the height of the left positive peak in D3 and the concentration of Y was calculated to be 0.9926.Six synthetic samples were analyzed, and the recovery for yttrium varied from 96.3% to 110.0%. The amounts of yttrium in three ytterbium metal samples were determined by the proposed approach with an average relative standard deviation (RSD)of 2.5%, and the detection limit for yttrium was 0.016%. This novel correction technique is fast and convenient, since neither complicated model assumption nor time-consuming iteration is required. Furthermore, it is not affected by the wavelength drift inherent in monochromators that will severely reduce the accuracy of results obtained by some chemometric methods.

  2. Multilayer Clad Plate of Stainless Steel/Aluminum/Aluminum Alloy

    Institute of Scientific and Technical Information of China (English)

    YUAN Jiawei; PANG Yuhua; LI Ting

    2011-01-01

    The 3, 5, 20 layer clad plate from austenitic stainless steel, pure aluminum and aluminum alloy sheets were fabricated in different ways. The stretch and interface properties were measured. The result shows that 20 layer clad plate is better than the others. Well-bonded clad plate was successfully obtained in the following procedure: Basic clad sheet from 18 layer A11060/A13003sheets was firstly obtained with an initial rolling reduction of 44% at 450 ℃, followed by annealing at 300 ℃, and then with reduction of 50% at 550 ℃ from STS304 on each side. The best 20 layer clad plate was of 129 MPa bonding strength and 225 MPa stretch strength.

  3. Electrodeposition of aluminum on aluminum surface from molten salt

    Institute of Scientific and Technical Information of China (English)

    Wenmao HUANG; Xiangyu XIA; Bin LIU; Yu LIU; Haowei WANG; Naiheng MA

    2011-01-01

    The surface morphology,microstructure and composition of the aluminum coating of the electrodeposition plates in AlC13-NaC1-KC1 molten salt with a mass ratio of 8:1:1 were investigated by SEM and EDS.The binding force was measured by splat-cooling method and bending method.The results indicate that the coatings with average thicknesses of 12 and 9 μm for both plates treated by simple grinding and phosphating are compacted,continuous and well adhered respectively. Tetramethylammonium chloride (TMAC) can effectively prevent the growth of dendritic crystal,and the anode activation may improve the adhesion of the coating. Binding force analysis shows that both aluminum coatings are strongly adhered to the substrates.

  4. Modeling dissolution in aluminum alloys

    Science.gov (United States)

    Durbin, Tracie Lee

    2005-07-01

    Aluminum and its alloys are used in many aspects of modern life, from soda cans and household foil to the automobiles and aircraft in which we travel. Aluminum alloy systems are characterized by good workability that enables these alloys to be economically rolled, extruded, or forged into useful shapes. Mechanical properties such as strength are altered significantly with cold working, annealing, precipitation-hardening, and/or heat-treatments. Heat-treatable aluminum alloys contain one or more soluble constituents such as copper, lithium, magnesium, silicon and zinc that individually, or with other elements, can form phases that strengthen the alloy. Microstructure development is highly dependent on all of the processing steps the alloy experiences. Ultimately, the macroscopic properties of the alloy depend strongly on the microstructure. Therefore, a quantitative understanding of the microstructural changes that occur during thermal and mechanical processing is fundamental to predicting alloy properties. In particular, the microstructure becomes more homogeneous and secondary phases are dissolved during thermal treatments. Robust physical models for the kinetics of particle dissolution are necessary to predict the most efficient thermal treatment. A general dissolution model for multi-component alloys has been developed using the front-tracking method to study the dissolution of precipitates in an aluminum alloy matrix. This technique is applicable to any alloy system, provided thermodynamic and diffusion data are available. Treatment of the precipitate interface is explored using two techniques: the immersed-boundary method and a new technique, termed here the "sharp-interface" method. The sharp-interface technique is based on a variation of the ghost fluid method and eliminates the need for corrective source terms in the characteristic equations. In addition, the sharp-interface method is shown to predict the dissolution behavior of precipitates in aluminum

  5. Yttrium doped TiO2 porous film photoanode for dye-sensitized solar cells with enhanced photovoltaic performance

    Science.gov (United States)

    Qu, Xiaofei; Hou, Yuchen; Liu, Meihua; Shi, Liang; Zhang, Mingqian; Song, Hongbing; Du, Fanglin

    In this paper, TiO2 photoanodes were doped with yttrium under different doping concentrations via hydrothermal method and further employed to assemble dye-sensitized solar cells (DSSCs). XRD, XPS, SEM, TEM, UV-Vis DRS and PL measurements were carried out to investigate the yttrium doping effects on crystal structure, chemical status, optical properties and dye loading capacity of the photoanodes. The photovoltaic performance of the photoanodes with various yttrium doping concentration was measured by recording the photocurrent-photovoltaic curves, and the result indicated that TiO2:0.006 Y exhibited the best power conversion efficiency with high short circuit current density (Jsc) and open circuit voltage (Voc). This improvement may be due to the enhanced visible light harvesting, increased dye loading capacity and reduced photoelectron recombination.

  6. Corrosion Behavior of Mg-6Al-1Zn+XRE Magnesium Alloy with Minor Addition of Yttrium

    Science.gov (United States)

    Manivannan, S.; Babu, S. P. Kumaresh; Sundarrajan, Srinivasan

    2015-04-01

    The effect of yttrium addition on the microstructure of Mg-6Al-1Zn alloy was investigated by optical microscopy, x-ray diffraction analysis, and scanning electron microscopy. The experimental alloys were prepared by melting high-purity Mg, Al, Zn, and Y, respectively. Melting was carried out in a Inconel 718 crucible under SF6 and ultra pure Ar (99.999%) gas mixture environment using electric arc furnace. The corrosion behavior of Mg-6Al-1Zn+ xYttrium ( x = 0.5, 1.0 and 1.5 wt.% Y) magnesium alloy with different levels of yttrium additions was studied in 3.5 wt.% NaCl solution. Microstructure of yttrium-added alloy shows that higher grainrefinement is obtained in Mg-6Al-1Zn+0.5wt.%Y. Increasing yttrium content reduces the size of α-grain and alters the distribution of the β-phase (Mg17Al12) from continuous network morphology to small and dispersive distribution. It forms secondary intermetallic phase Al2Y which has high melting point along the grain boundary. The corrosion resistance of Mg-6Al-1Zn magnesium alloy improved with addition of Yttrium. It was confirmed by the results of electrochemical polarization test. Based on the polarization curves, it is seen that fine precipitates of Al-Y intermetallic phase in Mg-6Al-1Zn alloy decrease the corrosion current density, thereby improving the corrosion resistance of the Mg-6Al-1Zn magnesium alloy.

  7. PET imaging of soluble yttrium-86-labeled carbon nanotubes in mice.

    Directory of Open Access Journals (Sweden)

    Michael R McDevitt

    Full Text Available The potential medical applications of nanomaterials are shaping the landscape of the nanobiotechnology field and driving it forward. A key factor in determining the suitability of these nanomaterials must be how they interface with biological systems. Single walled carbon nanotubes (CNT are being investigated as platforms for the delivery of biological, radiological, and chemical payloads to target tissues. CNT are mechanically robust graphene cylinders comprised of sp(2-bonded carbon atoms and possessing highly regular structures with defined periodicity. CNT exhibit unique mechanochemical properties that can be exploited for the development of novel drug delivery platforms. In order to evaluate the potential usefulness of this CNT scaffold, we undertook an imaging study to determine the tissue biodistribution and pharmacokinetics of prototypical DOTA-functionalized CNT labeled with yttrium-86 and indium-111 ((86Y-CNT and (111In-CNT, respectively in a mouse model.The (86Y-CNT construct was synthesized from amine-functionalized, water-soluble CNT by covalently attaching multiple copies of DOTA chelates and then radiolabeling with the positron-emitting metal-ion, yttrium-86. A gamma-emitting (111In-CNT construct was similarly prepared and purified. The constructs were characterized spectroscopically, microscopically, and chromatographically. The whole-body distribution and clearance of yttrium-86 was characterized at 3 and 24 hours post-injection using positron emission tomography (PET. The yttrium-86 cleared the blood within 3 hours and distributed predominantly to the kidneys, liver, spleen and bone. Although the activity that accumulated in the kidney cleared with time, the whole-body clearance was slow. Differential uptake in these target tissues was observed following intravenous or intraperitoneal injection.The whole-body PET images indicated that the major sites of accumulation of activity resulting from the administration of (86Y-CNT were

  8. Synthesis and Characterization of Large Surface Area Yttrium Oxide by Precipitation Method

    Institute of Scientific and Technical Information of China (English)

    崔大立; 龙志奇; 张顺利; 崔梅生; 黄小卫

    2004-01-01

    The method for preparing yttrium oxide with large specific surface area was introduced. By means of BET, SEM, TG and DTA analysis, the effects of precipitant, stirring velocity, non-RE impurity in solution, calcination temperature, on the surface area were studied respectively. The Y2O3 sample with specific surface area of more than 60 m2*g-1 and L.O.I less than 1% was prepared in the suitable precipitation condition and calcinations temperature when the ammonia used as precipitant. The SEM shows that the Y2O3 prepared with large surface area is the aggregation of about 50 nm particles.

  9. Structure degradation and conducting properties of the perovskite phase of yttrium ceramics

    CERN Document Server

    Kalanov, M U

    2002-01-01

    It is shown, that under normal conditions the perovskite phase of the yttrium ceramics of the [(Y,Ba)CuO sub 3 sub - subDELTA sub / sub 3] sub 3 is metastable and degrades in time. The degradation results in the YBa sub 2 Cu sub 3 O sub 7 sub - subdelta orthorhombic phase with transition into the superconducting state at T sub c = 91 K. The conductivity type changes thereby from the mixed metal-semiconductor character to the metallic one within the temperature interval of 100-300 K

  10. A nonreciprocal racetrack resonator based on vacuum-annealed magnetooptical cerium-substituted yttrium iron garnet.

    Science.gov (United States)

    Goto, Taichi; Onbasli, Mehmet C; Kim, Dong Hun; Singh, Vivek; Inoue, M; Kimerling, Lionel C; Ross, C A

    2014-08-11

    Vacuum annealed polycrystalline cerium substituted yttrium iron garnet (CeYIG) films deposited by radio frequency magnetron sputtering on non-garnet substrates were used in nonreciprocal racetrack resonators. CeYIG annealed at 800°C for 30 min provided a large Faraday rotation angle, close to the single crystal value. Crystallinity, magnetic properties, refractive indices and absorption coefficients were measured. The resonant transmission peak of the racetrack resonator covered with CeYIG was non-reciprocally shifted by applying an in-plane magnetic field.

  11. Highly Sensitive Fiber-Optic Faraday-Effect Magnetic Field Sensor Based on Yttrium Iron Garnet

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The principle and performance of a fiber-optic Faraday-effect magnetic-field sensor based on an yttrium iron garnet (YIG) and two flux concentrations are described. A single polarization maintaining optical fiber links the sensor head to the source and detection system, in which the technique of phase shift cancellation is used to cancel the phase shift that accumulate in the optical fiber. Flux concentrators were exploited to enhance the YIG crystal magneto optic sensitivity .The sensor system exhibited a noise-equivalent field of 8 and a 3 dB bandwidth of ~10 MHz.

  12. 钇的光度分析进展%Advancement of Spectrophotometric Analysis for Determining Yttrium

    Institute of Scientific and Technical Information of China (English)

    杨乡珍

    2001-01-01

    The advancement of spectrophotometry for determining yttrium has been reviewed.There are conventional spectrophotometry ,chemiluminescence method,flow-injection kinetic photometry and fluorophotometry.52 references are quoted.%对钇的光度分析方法,包括常规光度法、化学发光法、流动注射动力学法和荧光光度法等近些年的进展进行了综述。参考文献52篇。

  13. Erbium-doped yttrium aluminium garnet ablative laser treatment for endogenous ochronosis.

    Science.gov (United States)

    Chaptini, Cassandra; Huilgol, Shyamala C

    2015-08-01

    Ochronosis is a rare disease characterised clinically by bluish-grey skin discolouration and histologically by yellow-brown pigment deposits in the dermis. It occurs in endogenous and exogenous forms. Endogenous ochronosis, also known as alkaptonuria, is an autosomal recessive disease of tyrosine metabolism, resulting in the accumulation and deposition of homogentisic acid in connective tissue. We report a case of facial endogenous ochronosis and coexistent photodamage, which was successfully treated with erbium-doped yttrium aluminium garnet laser resurfacing and deep focal point treatment to remove areas of residual deep pigment.

  14. The Effect of Chelating Copolymer Additive on the Yttrium Iron Garnet Nanoparticle Formation

    Institute of Scientific and Technical Information of China (English)

    Wang; Cheng-chien

    2007-01-01

    1 Results Yttrium iron garnet (YIG) is a well-known ferromagnetic garnet material and has widely used in electronic devices[1].A new acrylic chelating polymer was developed to act as the additive of the preparation of YIG precursor in our previous study[2].The sintering temperature of YIG nanocrystal obtained by this YIG precursor (ACP) was magnificently descended from 1 000 to 600 ℃.In this study,we were further to study the effect of amount of chelating polymer and the compositions of chelating polyme...

  15. Superconductivity in fluorine and yttrium co-doped SmFeAsO

    Science.gov (United States)

    Lai, K. T.; Kwong, F. L.; Ng, Dickon H. L.

    2012-05-01

    Polycrystalline fluorine and yttrium co-doped SmFeAsO samples are synthesized by solid state sintering and their physical properties are studied. The lattice parameters of the Sm1-yYyFeAsO0.8F0.2 samples decrease with the increasing y due to the smaller Y ions and the stiffness of the Y-O bond. The maximum critical temperature Tc of the samples is at y = 0.05. This may be due to the fact that the strong interaction between Sm and Fe of the Fe-As bond is being re-disturbed by the doped Y ions.

  16. Scaling at the Mott-Hubbard metal-insulator transition in yttrium hydride

    CERN Document Server

    Hoekstra, A F T; Rosenbaum, T F

    2003-01-01

    A single yttrium hydride thin film is conveniently driven through the T 0 metal-insulator transition by fine-tuning the charge carrier density n via persistent photoconductivity at low temperature. Simultaneously, electrical conductivity and Hall measurements are performed for temperatures T down to 350 mK and magnetic fields up to 14 T. A scaling analysis is applied and critical exponents, resolved separately on the metallic and insulating sides of the critical region, are determined consistently. We introduce corrections to scaling to invoke collapse of the data onto a single master curve over an extended region of the (n, T) phase diagram.

  17. Preparation, characterization and dielectric behaviour of some yttrium doped strontium stannates

    Indian Academy of Sciences (India)

    P K Bajpai; Kuldeep Ratre; Mukul Pastor; T P Sinha

    2003-08-01

    Samples of Sr$_{(1–3x/2)}$Y$_x$SnO3 are prepared by usual solid state reaction route. X-ray diffraction studies confirm the formation of single cubic perovskite single phase. The dielectric constant and dielectric loss at 1 kHz were measured in the temperature range from room temperature up to ≅ 150°C. The dielectric constant decreases and losses increase with increased yttrium content in the samples. The percentage porosity and unit cell parameters are also calculated for the samples.

  18. Diffusion-bonded beryllium aluminum optical structures

    Science.gov (United States)

    Grapes, Thomas F.

    2003-12-01

    Beryllium aluminum material can present significant advantages for optical support structures. A likely advantage of beryllium aluminum compared to aluminum or titanium for such structures is its higher specific stiffness. However, beryllium aluminum material is significantly more expensive than most competing materials. The cost problem with beryllium aluminum is exacerbated if fabrication methods that result in near net shape parts are not used. Near net shape methods result in the least amount of material "thrown away" in the fabrication process. Casting is a primary example of near net shape manufacturing that is appropriate for some optical support structures. Casting aluminum, and other materials as well, is common. Casting of beryllium aluminum is very difficult, however, and has not had significant success. Diffusion bonding - a different approach for achieving near net shape beryllium aluminum optical support structures, was pursued and accomplished. Diffusion bonding is a term used to describe the joining of solid metal pieces under high temperature and pressure, but without melting. Three different optical support structures were designed and built of beryllium aluminum using diffusion bonding. Relatively small solid beryllium aluminum pieces were arranged together and then joined under hot isostatic pressure conditions. The resulting relatively large pressure bonded part was then machined to achieve the final product. Significant cost savings as compared to machining the part from a solid block were realized. Difficulties achieving diffusion bonds in complex joints were experienced and addressed.

  19. Aluminum/air electrochemical cells

    OpenAIRE

    Wang, Lei; 王雷

    2014-01-01

    Aluminum (Al) is a very promising energy carrier given its high capacity and energy density, low cost, earth abundance and environmental benignity. The Al/air battery as a kind of metal/air electrochemical cell attracts tremendous attention. Traditional Al/air batteries suffer from the self-corrosion and related safety problems. In this work, three new approaches were investigated to tackle these challenges and to develop high-performance Al/air cells: (1) incorporate an additional hydrogen/a...

  20. Electrically Conductive Anodized Aluminum Surfaces

    Science.gov (United States)

    Nguyen, Trung Hung

    2006-01-01

    Anodized aluminum components can be treated to make them sufficiently electrically conductive to suppress discharges of static electricity. The treatment was conceived as a means of preventing static electric discharges on exterior satin-anodized aluminum (SAA) surfaces of spacecraft without adversely affecting the thermal-control/optical properties of the SAA and without need to apply electrically conductive paints, which eventually peel off in the harsh environment of outer space. The treatment can also be used to impart electrical conductivity to anodized housings of computers, medical electronic instruments, telephoneexchange equipment, and other terrestrial electronic equipment vulnerable to electrostatic discharge. The electrical resistivity of a typical anodized aluminum surface layer lies between 10(exp 11) and 10(exp 13) Omega-cm. To suppress electrostatic discharge, it is necessary to reduce the electrical resistivity significantly - preferably to anodized surface becomes covered and the pores in the surface filled with a transparent, electrically conductive metal oxide nanocomposite. Filling the pores with the nanocomposite reduces the transverse electrical resistivity and, in the original intended outer-space application, the exterior covering portion of the nanocomposite would afford the requisite electrical contact with the outer-space plasma. The electrical resistivity of the nanocomposite can be tailored to a value between 10(exp 7) and 10(exp 12) Omega-cm. Unlike electrically conductive paint, the nanocomposite becomes an integral part of the anodized aluminum substrate, without need for adhesive bonding material and without risk of subsequent peeling. The electrodeposition process is compatible with commercial anodizing production lines. At present, the electronics industry uses expensive, exotic, electrostaticdischarge- suppressing finishes: examples include silver impregnated anodized, black electroless nickel, black chrome, and black copper. In

  1. The enhanced visible light photocatalytic activity of yttrium-doped BiOBr synthesized via a reactable ionic liquid

    Energy Technology Data Exchange (ETDEWEB)

    He, Minqiang; Li, Weibing [School of Chemistry and Chemical Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013 (China); Xia, Jiexiang, E-mail: xjx@ujs.edu.cn [School of Chemistry and Chemical Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013 (China); Xu, Li; Di, Jun [School of Chemistry and Chemical Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013 (China); Xu, Hui [School of the Environment, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013 (China); Yin, Sheng [School of Chemistry and Chemical Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013 (China); Li, Huaming, E-mail: lhm@ujs.edu.cn [School of Chemistry and Chemical Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013 (China); Li, Mengna [School of Chemistry and Chemical Engineering, Jiangsu University, 301 Xuefu Road, Zhenjiang 212013 (China)

    2015-03-15

    Graphical abstract: Yttrium (Y)-doped BiOBr with different Y doping concentrations has been synthesized via solvothermal method in the presence of reactable ionic liquid 1-hexadecyl-3-methylimidazolium bromide ([C16mim]Br). The photocatalytic activities of the yttrium doped BiOBr samples were evaluated by the degradation of ciprofloxacin (CIP) and rhodamine B (RhB) under visible-light irradiation. The yttrium doped BiOBr exhibited enhanced photocatalytic activity for the degradation of the two types of pollutants, and the 5wt%Y-doped BiOBr showed the highest photocatalytic activity. The enhanced photocatalytic performance could be attributed to the reduced band gap and improved separation of electron–hole pairs. - Highlights: • Yttrium (Y)-doped BiOBr composites have been synthesized via solvothermal method in the presence of reactable ionic liquid [C16mim]Br. • The yttrium doped BiOBr exhibited enhanced photocatalytic activity for the degradation of ciprofloxacin (CIP) and rhodamine B (RhB). • The enhanced photocatalytic performance could be attributed to the reduced band gap and improved separation of electron–hole pairs. - Abstract: Yttrium (Y)-doped BiOBr with different Y doping concentrations has been synthesized via solvothermal method in the presence of reactable ionic liquid 1-hexadecyl-3-methylimidazolium bromide ([C{sub 16}mim]Br). Their structures, morphologies and optical properties were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS) and UV–vis diffuse reflectance spectroscopy (DRS). The photocatalytic activities of the yttrium doped BiOBr samples were evaluated by the degradation of ciprofloxacin (CIP) and rhodamine B (RhB) under visible-light irradiation. The yttrium doped BiOBr exhibited enhanced photocatalytic activity for the degradation of the two types of pollutants, and the 5wt%Y-doped BiOBr showed the highest

  2. Purification technology of molten aluminum

    Institute of Scientific and Technical Information of China (English)

    孙宝德; 丁文江; 疏达; 周尧和

    2004-01-01

    Various purification methods were explored to eliminate the dissolved hydrogen and nonmetallic inclusions from molten aluminum alloys. A novel rotating impeller head with self-oscillation nozzles or an electromagnetic valve in the gas circuit was used to produce pulse gas currents for the rotary impeller degassing method. Water simulation results show that the size of gas bubbles can be decreased by 10%-20% as compared with the constant gas current mode. By coating ceramic filters or particles with active flux or enamels, composite filters were used to filter the scrap A356 alloy and pure aluminum. Experimental results demonstrate that better filtration efficiency and operation performance can be obtained. Based on numerical calculations, the separation efficiency of inclusions by high frequency magnetic field can be significantly improved by using a hollow cylinder-like separator or utilizing the effects of secondary flow of the melt in a square separator. A multi-stage and multi-media purification platform based on these methods was designed and applied in on-line processing of molten aluminum alloys. Mechanical properties of the processed scrap A356 alloy are greatly improved by the composite purification.

  3. COMPARATIVE ANALYSIS OF STEEL AND ALUMINUM STRUCTURES

    Directory of Open Access Journals (Sweden)

    Josip Peko

    2016-12-01

    Full Text Available This study examined steel and aluminum variants of modern exhibition structures in which the main design requirements include low weight (increased span/depth ratio, transportation, and construction and durability (resistance to corrosion. This included a design situation in which the structural application of aluminum alloys provided an extremely convenient and practical solution. Viability of an aluminum structure depends on several factors and requires a detailed analysis. The overall conclusion of the study indicated that aluminum can be used as a structural material and as a viable alternative to steel for Croatian snow and wind load values and evidently in cases in which positive properties of aluminum are required for structural design. Furthermore, a structural fire analysis was conducted for an aluminum variant structure by using a zone model for realistic fire analysis. The results suggested that passive fire protection for the main structural members was not required in the event of areal fire with duration of 60 min.

  4. [Link between aluminum neurotoxicity and neurodegenerative disorders].

    Science.gov (United States)

    Kawahara, Masahiro

    2016-07-01

    Aluminum is an old element that has been known for a long time, but some of its properties are only now being discovered. Although environmentally abundant, aluminum is not essential for life; in fact, because of its specific chemical properties, aluminum inhibits more than 200 biologically important functions and exerts various adverse effects in plants, animals, and humans. Aluminum is a widely recognized neurotoxin. It has been suggested that there is a relationship between exposure to aluminum and neurodegenerative diseases, including dialysis encephalopathy, amyotrophic lateral sclerosis and parkinsonism dementia in the Kii Peninsula and Guam, as well as Alzheimer' s disease: however, this claim remains to be verified. In this chapter, we review the detailed characteristics of aluminum neurotoxicity and the link between Alzheimer' s disease and other neurodegenerative diseases, based on recent findings on metal-metal interactions and the functions of metalloproteins in synapses.

  5. Optical Transmittance of Anodically Oxidized Aluminum Alloy

    Science.gov (United States)

    Saito, Mitsunori; Shiga, Yasunori; Miyagi, Mitsunobu; Wada, Kenji; Ono, Sachiko

    1995-06-01

    Optical transmittance and anisotropy of anodic oxide films that were made from pure aluminum and an aluminum alloy (A5052) were studied. The alloy oxide film exhibits an enhanced polarization function, particularly when anodization is carried out at a large current density. It was revealed by chemical analysis that the alloy oxide film contains a larger amount of unoxidized aluminum than the pure-aluminum oxide film. The polarization function can be elucidated by considering unoxidized aluminum particles that are arranged in the columnar structure of the alumina film. Electron microscope observation showed that many holes exist in the alloy oxide film, around which columnar cells are arranged irregularly. Such holes and irregular cell arrangement cause the increase in the amount of unoxidized aluminum, and consequently induces scattering loss.

  6. Structure of Liquid Aluminum and Hydrogen Absorption

    Institute of Scientific and Technical Information of China (English)

    LIU Yang; DAI Yongbing; WANG Jun; SHU Da; SUN Baode

    2011-01-01

    The hydrogen content in aluminum melts at different temperature was detected. The structure in aluminum melts was investigated by molecular dynamics simulation. The first peak position of pair correlation function, atomic coordination number and viscosity of aluminum melts were calculated and they changed abnormally in the same temperature range. The mechanism of hydrogen absorption has been discussed. From molecular dynamics calculations, the interdependence between melt structural properties and hydrogen absorption were obtained.

  7. Precision Wavelength Measurements And Identifications Of EUV Lines From Highly Charged L-Shell yttrium Ions

    Science.gov (United States)

    Silwal, Roshani; Dreiling, Joan; Gillaspy, John; Takacs, Endre; Ralchenko, Yuri

    2016-05-01

    We present the measurements of extreme-ultraviolet spectra of the L-shell ions of highly charged yttrium (Y29+- Y36+) created and trapped in the electron beam ion trap (EBIT) of the National Institute of Standards and Technology. Few Na-like, Mg-like and Al-like yttrium lines (Y26+- Y28+) are reported as well. In order to reach the desired ionization stages, the beam energy was systematically varied from 2.3 keV to 6 keV during the experiment. A flat-field grazing-incidence spectrometer was used to record the spectra in the wavelength range of 4.022 nm to 19.957 nm. The wavelength calibration was provided by the previously measured lines of neon, xenon, oxygen and iron. A total of 63 new spectral lines (allowed and forbidden) corresponding to the Δn = 0 transitions within n = 2 and 3 have been identified using collisional-radiative simulations of the non-Maxwellian EBIT plasma. The total uncertainties assigned to the measured wavelengths vary between 0.001 nm to 0.003 nm and include contributions from calibration uncertainties, statistical uncertainties from the line fits, and estimated systematic uncertainties.

  8. Thermally stable yttrium-scandium oxide high-k dielectrics deposited by a solution process

    Science.gov (United States)

    Hu, Wenbing; Frost, Bradley; Peterson, Rebecca L.

    2016-03-01

    We investigated the thermal stability of electrical properties in ternary alloy (Y x Sc1-x )2O3 high-k oxides as a function of yttrium fraction, x. The yttrium-scandium oxide dielectric films are deposited using a facile ink-based process. The oxides have a stoichiometry-dependent relative dielectric constant of 26.0 to 7.7 at 100 kHz, low leakage current density of 10-8 A·cm-2, high breakdown field of 4 MVṡcm-1, and interface trap density of 1012 cm-2·eV-1 with silicon. Compared with binary oxides, ternary alloys exhibit less frequency dispersion of the dielectric constant and a higher crystallization temperature. After crystallization is induced through a 900 °C anneal, ternary (Y0.6Sc0.4)2O3 films maintain their low leakage current and high breakdown field. In contrast, the electrical performance of the binary oxides significantly degrades following the same treatment. The solution-processed ternary oxide dielectrics demonstrated here may be used as high-k gate insulators in complementary metal-oxide semiconductor (CMOS) technologies, in novel electronic material systems and devices, and in printed, flexible thin film electronics, and as passivation layers for high power devices. These oxides may also be used as insulators in fabrication process flows that require a high thermal budget.

  9. Studies on Characterization, Optical Absorption, and Photoluminescence of Yttrium Doped ZnS Nanoparticles

    Directory of Open Access Journals (Sweden)

    Ranganaik Viswanath

    2014-01-01

    Full Text Available Pure ZnS and ZnS:Y nanoparticles were synthesized by a chemical coprecipitation route using EDTA-ethylenediamine as a stabilizing agent. X-ray diffraction (XRD, high resolution transmission electron microscopy (HRTEM, field emission scanning electron microscopy (FE-SEM, Fourier transform infrared spectrometry (FTIR, thermogravimetric-differential scanning calorimetry (TG-DSC, and UV-visible and photoluminescence (PL spectroscopy were employed to characterize the as-synthesized ZnS and ZnS:Y nanoparticles, respectively. XRD and TEM studies show the formation of cubic ZnS:Y particles with an average size of ~4.5 nm. The doping did not alter the phase of the zinc sulphide, as a result the sample showed cubic zincblende structure. The UV-visible spectra of ZnS and ZnS:Y nanoparticles showed a band gap energy value, 3.85 eV and 3.73 eV, which corresponds to a semiconductor material. A luminescence characteristics such as strong and stable visible-light emissions in the orange region alone with the blue emission peaks were observed for doped ZnS nanoparticles at room temperature. The PL intensity of orange emission peak was found to be increased with an increase in yttrium ions concentration by suppressing blue emission peaks. These results strongly propose that yttrium doped zinc sulphide nanoparticles form a new class of luminescent material.

  10. Yttrium scandate thin film as alternative high-permittivity dielectric for germanium gate stack formation

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Cimang, E-mail: cimang@adam.t.u-tokyo.ac.jp; Lee, Choong Hyun; Nishimura, Tomonori; Toriumi, Akira [Department of Materials Engineering, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8656 (Japan); JST, CREST, 7-3-1 Hongo, Tokyo 113-8656 (Japan)

    2015-08-17

    We investigated yttrium scandate (YScO{sub 3}) as an alternative high-permittivity (k) dielectric thin film for Ge gate stack formation. Significant enhancement of k-value is reported in YScO{sub 3} comparing to both of its binary compounds, Y{sub 2}O{sub 3} and Sc{sub 2}O{sub 3}, without any cost of interface properties. It suggests a feasible approach to a design of promising high-k dielectrics for Ge gate stack, namely, the formation of high-k ternary oxide out of two medium-k binary oxides. Aggressive scaling of equivalent oxide thickness (EOT) with promising interface properties is presented by using YScO{sub 3} as high-k dielectric and yttrium-doped GeO{sub 2} (Y-GeO{sub 2}) as interfacial layer, for a demonstration of high-k gate stack on Ge. In addition, we demonstrate Ge n-MOSFET performance showing the peak electron mobility over 1000 cm{sup 2}/V s in sub-nm EOT region by YScO{sub 3}/Y-GeO{sub 2}/Ge gate stack.

  11. Aluminum-stabilized NB3SN superconductor

    Science.gov (United States)

    Scanlan, Ronald M.

    1988-01-01

    An aluminum-stabilized Nb.sub.3 Sn superconductor and process for producing same, utilizing ultrapure aluminum. Ductile components are co-drawn with aluminum to produce a conductor suitable for winding magnets. After winding, the conductor is heated to convert it to the brittle Nb.sub.3 Sn superconductor phase, using a temperature high enough to perform the transformation but still below the melting point of the aluminum. This results in reaction of substantially all of the niobium, while providing stabilization and react-in-place features which are beneficial in the fabrication of magnets utilizing superconducting materials.

  12. Silicon reduces aluminum accumulation in rats: relevance to the aluminum hypothesis of Alzheimer disease.

    Science.gov (United States)

    Bellés, M; Sánchez, D J; Gómez, M; Corbella, J; Domingo, J L

    1998-06-01

    In recent years, a possible relation between the aluminum and silicon levels in drinking water and the risk of Alzheimer disease (AD) has been established. It has been suggested that silicon may have a protective effect in limiting oral aluminum absorption. The present study was undertaken to examine the influence of supplementing silicon in the diet to prevent tissue aluminum retention in rats exposed to oral aluminum. Three groups of adult male rats were given by gavage 450 mg/kg/day of aluminum nitrate nonahydrate 5 days a week for 5 weeks. Concurrently, animals received silicon in the drinking water at 0 (positive control), 59, and 118 mg Si/L. A fourth group (-Al, - Si) was designated as a negative control group. At the end of the period of aluminum and silicon administration, urines were collected for 4 consecutive days, and the urinary aluminum levels were determined. The aluminum concentrations in the brain (various regions), liver, bone, spleen, and kidney were also measured. For all tissues, aluminum levels were significantly lower in the groups exposed to 59 and 118 mg Si/L than in the positive control group; significant reductions in the urinary aluminum levels of the same groups were also found. The current results corroborate that silicon effectively prevents gastrointestinal aluminum absorption, which may be of concern in protecting against the neurotoxic effects of aluminum.

  13. The Aluminum Deep Processing Project of North United Aluminum Landed in Qijiang

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>On April 10,North United Aluminum Company respectively signed investment cooperation agreements with Qijiang Industrial Park and Qineng Electricity&Aluminum Co.,Ltd,signifying the landing of North United Aluminum’s aluminum deep processing project in Qijiang.

  14. Structure and morphological analysis of various composition of yttrium doped-zirconia prepared from local zircon sand

    Science.gov (United States)

    Rahmawati, F.; Permadani, I.; Heraldy, E.; Syarif, D. G.; Soepriyanto, S.

    2016-11-01

    Yttrium ions, Y3+ were doped into ZrO2 that was synthesized from zircon sand. Zircon sand is a side product of tin mining plant in Bangka Island, Indonesia. Solid state reaction was chosen as the method to dope yttrium ions from Y2O3 into ZrO2 at various % mol of 4.5; 8 and 10. This research aims to understand the crystal structure, morphological analysis and particle size analysis. The X-ray diffraction analysis equipped with Le Bail refinement found that the prepared ZrO2 is in two phases of the monoclinic and tetragonal structure, and the structure changed to cubic after yttrium ions doping. However, the monoclinic and tetragonal still exist. Various yttrium concentrations provide different morphology, in which 4.5 YSZ shows a blocking phase indicated as the presence of impurities. The blocking phase seems to prevent sintering and allows a line crack on the material layer. Meanwhile, 8YSZ and 10YSZ show homogeneous morphology and without provides a line crack. The mean particle size after sintering is in between 1.1 - 1.5 μm.

  15. Pengaruh Penambahan Yttrium Terhadap Struktur Mikro, Sifat Mekanik Dan Ketahanan Termal Pada Paduan Mg-6zn Sebagai Aplikasi Engine Block

    Directory of Open Access Journals (Sweden)

    Indra Bagas Pramasta

    2015-03-01

    Full Text Available Penelitian ini bertujuan untuk menganalisis pengaruh variasi penambahan Yttrium (Y terhadap struktur mikro, kekerasan dan ketahanan termal pada paduan magnesium – zinc. Magnesium (Mg telah menjadi solusi untuk pengembangan material ringan. Paduan magnesium yang memiliki rasio kekuatan material berbanding massa material yang tinggi membuatnya baik digunakan pada aplikasi otomotif seperti steering wheel, gearbox house, seat frames dan cylinder block. Penelitian ini memadukan magnesium-zinc-yttrium dalam komposisi yang berbeda. Komposisi yttriumnya adalah 0,5% wt ; 2% wt dan 4% wt. Pengecoran yang dilakukan adalah pengecoan konvensional dengan temperatur melting 750°C dengan waktu penahanan 60 menit. Pengujian yang dilakukan yaitu pengujian struktur mikro, identifikasi fasa, komposisi fasa, ketahanan termal dan kekerasan. Berdasarkan pengujian yang dilakukan menunjukkan bahwa yttrium dapat menyebabkan berubahnya struktur mikro dan fasa serta meningkatkan kekerasan dan ketahanan termal pada sampel. Hasil analisa menunjukkan 4 fasa dominan yang muncul pada sampel yaitu α-Mg, MgZn, Mg3YZn6 dan Mg3Y2Zn3. Kekerasan tertinggi adalah 74 BHN pada sampel 4% wt yttrium dan rata-rata sampel dapat digunakan sampai temperatur dibawah 250 ͦC.

  16. Influence of yttrium iron garnet thickness and heater opacity on the nonlocal transport of electrically and thermally excited magnons

    NARCIS (Netherlands)

    Shan, Juan; Cornelissen, Ludo J.; Vlietstra, Nynke; Ben Youssef, Jamal; Kuschel, Timo; Duine, Rembert; Van Wees, Bart J.

    2016-01-01

    We studied the nonlocal transport behavior of both electrically and thermally excited magnons in yttrium iron garnet (YIG) as a function of its thickness. For electrically injected magnons, the nonlocal signals decrease monotonically as the YIG thickness increases. For the nonlocal behavior of the t

  17. Distribution and fractionation of rare earth elements and Yttrium in suspended and bottom sediments of the Kali estuary, western India

    Digital Repository Service at National Institute of Oceanography (India)

    Suja, S.; Fernandes, L.L.; Rao, V.P.

    References Barrat Jean-Alix, Zanda B, Moynier F, Bollinger C, Liorzou C, Bayon G (2012) Geochemistry of CI chondrites: Major and trace elements, and Cu and Zn Isotopes. Geochim Cosmochim Acta 83: 79- 92. Bau M (1999) Scavenging of yttrium and rare earths...

  18. Effect of surface composition of yttrium-stabilized zirconia on partial oxidation of methane to synthesis gas.

    NARCIS (Netherlands)

    Zhu, Jianjun; Ommen, van Jan G.; Knoester, A.; Lefferts, Leon

    2005-01-01

    Catalytic partial oxidation of methane to synthesis gas (CPOM) over yttrium-stabilized zirconia (YSZ) was studied within a wide temperature window (500¿1100 °C). The catalysts were characterized by X-ray fluorescence (XRF) and low-energy ion scattering (LEIS). The influence of calcination temperatur

  19. Sign of inverse spin Hall voltages generated by ferromagnetic resonance and temperature gradients in yttrium iron garnet platinum bilayers

    NARCIS (Netherlands)

    Schreier, Michael; Bauer, Gerrit E. W.; Vasyuchka, Vitaliy I.; Flipse, Joost; Uchida, Ken-ichi; Lotze, Johannes; Lauer, Viktor; Chumak, Andrii V.; Serga, Alexander A.; Daimon, Shunsuke; Kikkawa, Takashi; Saitoh, Eiji; van Wees, Bart J.; Hillebrands, Burkard; Gross, Rudolf; Goennenwein, Sebastian T. B.

    2015-01-01

    We carried out a concerted effort to determine the absolute sign of the inverse spin Hall effect voltage generated by spin currents injected into a normal metal. We focus on yttrium iron garnet (YIG)vertical bar platinum bilayers at room temperature, generating spin currents by microwaves and temper

  20. Pemisahan Unsur Samarium dan Yttrium dari Mineral Tanah Jarang dengan Teknik Membran Cair Berpendukung (Supported Liquid Membrane

    Directory of Open Access Journals (Sweden)

    Amri Amin

    2009-06-01

    Full Text Available he increasing use of rare earth elements in high technology industries needs to be supported by developmental work for the separation of elements. The research objective is fiercely attracting and challenging considering the similarity of bath physical and chemical properties among these elements. The rate separation of samarium and yttrium elements using supported liquid membrane has been studied. Polytetrafluoroethylene (PTFE with pore size of 0.45 µm has been used as the membrane and di(2-ethylhexyl phosphate (D2EHP in hexane has been used as a carrier and nitric acid solution has been used as receiving phase. Result of experiments showed that the best separation rate of samarium and yttrium elements could be obtained at feeding phase of pH 3.0, di(2-ethylhexyl phosphate (D2EHP concentration of 0.3 M, agitation rate of 700 rpm, agitation time of 2 hours, and nitric acid and its solution concentrations of 1.0 M and 0.1 M, respectively. At this condition, separation rates of samarium and yttrium were 64.4 and 67.6%, respectively.   Keywords: liquid membrane, rare earth elements, samarium, yttrium

  1. Long-Term Palliative Effect of Stenting in Gastric Outlet Obstruction Due to Transarterial Chemoembolization with Yttrium-90 in a Patient with Metastatic Neuroendocrine Tumor

    Science.gov (United States)

    Caglar, Erkan; Doğusoy, Gulen; Kabasakal, Levent; Dobrucali, Ahmet

    2016-01-01

    Internal radioembolization with yttrium-90 is a promising treatment method, predominantly for liver tumors. However, the shifting of yttrium-90-loaded spherules into the arteries and veins that supply the duodenum and stomach, leading to ulceration, hemorrhage, perforation, and outlet obstruction of these organs, is one of the major undesirable consequences of this technique. We report a case of gastric outlet obstruction (GOO) due to antropyloric stenosis with ulceration, edema, and inflammation following transarterial yttrium-90 treatment for a metastatic neuroendocrine tumor in a 58-year-old man. Stenting was used for palliation in this case. GOO improved after stenting and recovery of oral intake was permanent after stent removal. PMID:27353368

  2. Effect of Yttrium Pre-Implantation on Implantation Behavior of Ti-6Al-4V Alloy in Nitrogen Plasma Immersion Ion Implantation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    In order to increase the peak depth of nitrogen atoms during the nitrogen plasma immersion ion implantation of Ti-6Al-4V alloy, the rare earth metal yttrium was applied. In the experiment, yttrium and nitrogen ions were implanted under the voltage of 20 and 30 kV, respectively. In the samples with yttrium pre-implantation for 30 min, the Auger electron spectroscopy(AES) analysis shows that the peak depth of the nitrogen atoms increases from 50 up to 100 nm. It can also be seen from the tribological tests that the wear resistance of these samples is increased remarkably.

  3. Laboratory Powder Metallurgy Makes Tough Aluminum Sheet

    Science.gov (United States)

    Royster, D. M.; Thomas, J. R.; Singleton, O. R.

    1993-01-01

    Aluminum alloy sheet exhibits high tensile and Kahn tear strengths. Rapid solidification of aluminum alloys in powder form and subsequent consolidation and fabrication processes used to tailor parts made of these alloys to satisfy such specific aerospace design requirements as high strength and toughness.

  4. Sanmenxia strives to create aluminum industrial base

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>Contradiction between rich alumina resource and relatively weak electrolytic aluminum production capacity is the "bottleneck" inhibiting development of aluminum industry in San-menxia. During the period of "11th Five-Year Development", Sanmenxia will relay on its

  5. Wilson's disease; increased aluminum in liver.

    Science.gov (United States)

    Yasui, M; Yoshimasu, F; Yase, Y; Uebayashi, Y

    1979-01-01

    Interaction of trace metal metabolism was studied in a patient with Wilson's dease. Atomic absorption analysis showed markedly increased urinary excretion of copper and aluminum and an increased aluminum content was found in the biopsied liver by neutron activation analysis. These findings suggest a complicated pathogenetic mechanism involving other metals besides copper in the Wilson's disease.

  6. Recrystallization in Commercially Pure Aluminum

    DEFF Research Database (Denmark)

    Bay, Bent; Hansen, Niels

    1984-01-01

    Recrystallization behavior in commercial aluminum with a purity of 99.4 pct was studied by techniques such as high voltage electron microscopy, 100 kV transmission electron microscopy, and light microscopy. Sample parameters were the initial grain size (290 and 24 microns) and the degree of defor......Recrystallization behavior in commercial aluminum with a purity of 99.4 pct was studied by techniques such as high voltage electron microscopy, 100 kV transmission electron microscopy, and light microscopy. Sample parameters were the initial grain size (290 and 24 microns) and the degree...... (FeAl3), which start to become operative when the degree of deformation is raised from 15 to 30 pct. The temperature of nucleation and of recrystallization decreases when the degree of deformation is increased and the initial grain size is decreased. The recrystallized grain size follows the same...... trend and it is observed that the refinement of the recrystallized grain size caused by an increasing degree of deformation and decreasing initial grain size is enhanced by the FeAl3 particles (when the degree of deformation is raised from 15 to 30 pct). Finally, the structural and kinetic observations...

  7. Aluminum honeycomb impact limiter study

    Energy Technology Data Exchange (ETDEWEB)

    Yaksh, M.C.; Thompson, T.C. (Nuclear Assurance Corp., Norcross, GA (United States)); Nickell, R.E. (Applied Science and Technology, Inc., Poway, CA (United States))

    1991-07-01

    Design requirements for a cask transporting radioactive materials must include the condition of the 30-foot free fall of the cask onto an unyielding surface. To reduce the deceleration loads to a tolerable level for all the components of the cask, a component (impact limiter) is designed to absorb the kinetic energy. The material, shape, and method of attachment of the impact limiter to the cask body comprises the design of the impact limiter. The impact limiter material of interest is honeycomb aluminum, and the particular design examined was for the NAC Legal Weight Truck cask (NAC-LWT) for spent fuel from light water reactors. The NAC-LWT has a design weight of 52,000 pounds, and it has a nominal length of 200 inches. The report describes the numerical calculations embodied in the FADE program to determine the accelerations and crush strain resulting from an arbitrary height and angle of orientation. Since the program serves as a design tool, static tests are performed to assess the effect of the shell containing the honeycomb aluminum. The static tests and their results are contained in the study. The static tests are used to demonstrate for licensing purposes the level of accelerations imposed on the cask during a 30-foot drop. 3 refs., 41 figs., 15 tabs.

  8. Aluminum corrosion product release kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, Matt, E-mail: Matthew.Edwards@cnl.ca; Semmler, Jaleh; Guzonas, Dave; Chen, Hui Qun; Toor, Arshad; Hoendermis, Seanna

    2015-07-15

    Highlights: • Release of Al corrosion product was measured in simulated post-LOCA sump solutions. • Increased boron was found to enhance Al release kinetics at similar pH. • Models of Al release as functions of time, temperature, and pH were developed. - Abstract: The kinetics of aluminum corrosion product release was examined in solutions representative of post-LOCA sump water for both pressurized water and pressurized heavy-water reactors. Coupons of AA 6061 T6 were exposed to solutions in the pH 7–11 range at 40, 60, 90 and 130 °C. Solution samples were analyzed by inductively coupled plasma atomic emission spectroscopy, and coupon samples were analyzed by secondary ion mass spectrometry. The results show a distinct “boron effect” on the release kinetics, expected to be caused by an increase in the solubility of the aluminum corrosion products. New models were developed to describe both sets of data as functions of temperature, time, and pH (where applicable)

  9. Gating of Permanent Molds for ALuminum Casting

    Energy Technology Data Exchange (ETDEWEB)

    David Schwam; John F. Wallace; Tom Engle; Qingming Chang

    2004-03-30

    This report summarizes a two-year project, DE-FC07-01ID13983 that concerns the gating of aluminum castings in permanent molds. The main goal of the project is to improve the quality of aluminum castings produced in permanent molds. The approach taken was determine how the vertical type gating systems used for permanent mold castings can be designed to fill the mold cavity with a minimum of damage to the quality of the resulting casting. It is evident that somewhat different systems are preferred for different shapes and sizes of aluminum castings. The main problems caused by improper gating are entrained aluminum oxide films and entrapped gas. The project highlights the characteristic features of gating systems used in permanent mold aluminum foundries and recommends gating procedures designed to avoid common defects. The study also provides direct evidence on the filling pattern and heat flow behavior in permanent mold castings.

  10. Gelling nature of aluminum soaps in oils.

    Science.gov (United States)

    Wang, Xiaorong; Rackaitis, Mindaugas

    2009-03-15

    Aluminum soaps are notable for their ability to form soap-hydrocarbon gels of high viscosity. For more than half a century, it has been believed that the gelling mechanism is due to a formation of polymeric chains of aluminum molecules with the aluminum atoms linking along the axis and with the fatty acid chain extended sideways. Here we report results from an investigation using high-resolution electron microscopy and rheology measurements that clearly resolve the ambiguity. Our results reveal that the gelling mechanism stems from the formation of spherical nano-sized micelles from aluminum soap molecules, and those colloidal micelle particles then aggregate into networks of highly fractal and jammed structures. The earlier proposed polymer chain-like structure is definitely incorrect. The discovery of aluminum soap particles could expand application of these materials to new technologies.

  11. Aluminum-based metal-air batteries

    Energy Technology Data Exchange (ETDEWEB)

    Friesen, Cody A.; Martinez, Jose Antonio Bautista

    2016-01-12

    Provided in one embodiment is an electrochemical cell, comprising: (i) a plurality of electrodes, comprising a fuel electrode that comprises aluminum and an air electrode that absorbs gaseous oxygen, the electrodes being operable in a discharge mode wherein the aluminum is oxidized at the fuel electrode and oxygen is reduced at the air electrode, and (ii) an ionically conductive medium, comprising an organic solvent; wherein during non-use of the cell, the organic solvent promotes formation of a protective interface between the aluminum of the fuel electrode and the ionically conductive medium, and wherein at an onset of the discharge mode, at least some of the protective interface is removed from the aluminum to thereafter permit oxidation of the aluminum during the discharge mode.

  12. Proposal of recycling system for waste aluminum

    Directory of Open Access Journals (Sweden)

    Š. Valenčík

    2008-04-01

    Full Text Available Introduced work is focused on waste aluminum recycling process with objective to propose complex production system for recovering of aluminum and some aluminum alloys. Solution is supported by extended analysis concerning purpose, basis and system sequences for recyclation. Based on that, sources, possibilities and conditions for recycling are formed. This has been used in proposal of manufacturing system. The principle is the structural proposal of manufacturing system, which does not only differentiate the stage of aluminum melting process, but also related stages as gross separation, sizing, containerisation and batching, palletisation, stacking and some related operations. Production system respects technological specifications, requirements for rationalisation of manufacturing systems, technical and economical feasibility conditions and is considered in lower automation level. However production system solves complex problem of recycling of some types of aluminum, it improves flexibility, production, quality (melting by high enforcements and in protective atmosphere and extention of production (final products production.

  13. Trends in the global aluminum fabrication industry

    Science.gov (United States)

    Das, Subodh; Yin, Weimin

    2007-02-01

    The aluminum fabrication industry has become more vital to the global economy as international aluminum consumption has grown steadily in the past decades. Using innovation, value, and sustainability, the aluminum industry is strengthening its position not only in traditional packaging and construction applications but also in the automotive and aerospace markets to become more competitive and to face challenges from other industries and higher industrial standards. The aluminum fabrication industry has experienced a significant geographical shift caused by rapid growth in emerging markets in countries such as Brazil, Russia, India, and China. Market growth and distribution will vary with different patterns of geography and social development; the aluminum industry must be part of the transformation and keep pace with market developments to benefit.

  14. Aluminum phosphate shows more adjuvanticity than Aluminum hydroxide in recombinant hepatitis –B vaccine formulation

    Directory of Open Access Journals (Sweden)

    2008-08-01

    Full Text Available Background: Although a number of investigation have been carried out to find alternative adjuvants to aluminum salts in vaccine formulations, they are still extensively used due to their good track record of safety, low cost and proper adjuvanticity with a variety of antigens. Adsorption of antigens onto aluminum compounds depends heavily on electrostatic forces between adjuvant and antigen. Commercial recombinant protein hepatitis B vaccines containing aluminum hydroxide as adjuvant is facing low induction of immunity in some sections of the vaccinated population. To follow the current global efforts in finding more potent hepatitis B vaccine formulation, adjuvanticity of aluminum phosphate has been compared to aluminum hydroxide. Materials and methods: The adjuvant properties of aluminum hydroxide and aluminum phosphate in a vaccine formulation containing a locally manufactured hepatitis B (HBs surface antigen was evaluated in Balb/C mice. The formulations were administered intra peritoneally (i.p. and the titers of antibody which was induced after 28 days were determined using ELISA technique. The geometric mean of antibody titer (GMT, seroconversion and seroprotection rates, ED50 and relative potency of different formulations were determined. Results: All the adjuvanicity markers obtained in aluminum phosphate formulation were significantly higher than aluminum hydroxide. The geometric mean of antibody titer of aluminum phosphate was approximately three folds more than aluminum hydroxide. Conclusion: Aluminum phosphate showed more adjuvanticity than aluminum hydroxide in hepatitis B vaccine. Therefore the use of aluminum phosphate as adjuvant in this vaccine may lead to higher immunity with longer duration of effects in vaccinated groups.

  15. Characterization of aluminum surfaces: Sorption and etching

    Science.gov (United States)

    Polkinghorne, Jeannette Clera

    Aluminum, due to its low density and low cost, is a key material for future lightweight applications. However, like other structural materials, aluminum is subject to various forms of corrosion damage that annually costs the United States approximately 5% of its GNP [1]. The main goal is to investigate the effects of various solution anions on aluminum surfaces, and specifically probe pit initiation and inhibition. Using surface analysis techniques including X-ray photoelectron spectroscopy, Auger electron spectroscopy, and scanning electron microscopy, results have been correlated with those obtained from electrochemical methods and a radiolabeling technique developed in the Wieckowski laboratory. Analysis of data has indicated that important variables include type of anion, solution pH, and applied electrode potential. While aggressive anions such as chloride are usually studied to elucidate corrosion processes to work ultimately toward inhibition, its corrosive properties can be successfully utilized in the drive for higher energy and smaller-scale storage devices. Fundamental information gained regarding anion interaction with the aluminum surface can be applied to tailor etch processes. Standard electrochemical techniques and SEM are respectively used to etch and analyze the aluminum substrate. Aluminum electrolytic capacitors are comprised of aluminum anode foil covered by an anodically grown aluminum oxide dielectric film, electrolytic paper impregnated with electrolyte, and aluminum cathode foil. Two main processes are involved in the fabrication of aluminum electrolytic capacitors, namely etching and anodic oxide formation. Etching of the anode foil results in a higher surface area (up to 20 times area enlargement compared to unetched foil) that translates into a higher capacitance gain, permitting more compact and lighter capacitor manufacture. Anodic oxide formation on the anode, creates the required dielectric to withstand high voltage operation. A

  16. Crystal Structure of Lithium Yttrium Borate LiY6O5(BO3)3

    Institute of Scientific and Technical Information of China (English)

    GAO Jian-Hua

    2006-01-01

    Single crystals of LiY6O5(BO3)3 were obtained by the flux method and its structure was determined by a four-circle automatic diffractometer with a MoKa radiation. It crystallizes in monoclinic, space group P21/n with a = 8.330(3), b = 15.444(4), c = 8.780(3) (A), β = 91.85(3)°, V =1129.0(6) (A)3, Z = 4, Mr= 796.83, F(000) = 1456, μ = 30.567 mm-1, Dc = 4.688 g/cm3, the final R =0.0722 and wR = 0.1304. It exhibits a three-dimensional framework of yttrium-oxygen polyhedra interconnected by common edges and corners. B and Li atoms are located in the planes and cavities formed by oxygen atoms, respectively.

  17. Chemoembolic Hepatopulmonary Shunt Reduction to Allow Safe Yttrium-90 Radioembolization Lobectomy of Hepatocellular Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Gaba, Ron C., E-mail: rgaba@uic.edu [University of Illinois Medical Center at Chicago, Department of Radiology, Section in Interventional Radiology (United States); VanMiddlesworth, Kyle A. [Midwestern University School of Medicine (United States)

    2012-12-15

    Yttrium-90 ({sup 90}Y) radioembolization represents an emerging transcatheter treatment option for the management of hepatocellular carcinoma (HCC). Elevation of the hepatopulmonary shunt fraction risks nontarget radiation to the lungs and may limit the use of {sup 90}Y therapy in patients with locally advanced disease with vascular invasion, who often demonstrate increased shunting. We present two cases in which patients with HCC and portal vein invasion resulting in elevated hepatopulmonary shunt fractions underwent chemoembolic shunt closure to allow safe {sup 90}Y radioembolization. Both patients demonstrated excellent tumor response and patient survival. On this basis, we propose a role for chemoembolic reduction of the lung shunt fraction before {sup 90}Y radioembolization in patients with extensive tumor-related hepatopulmonary shunting.

  18. Light emission of double-walled carbon nanotube filaments doped with yttrium and europium

    Institute of Scientific and Technical Information of China (English)

    SHU QinKe; WU DeHai; WANG KunLin; WEI JinQuan; ZHU HongWei; LI XinMing; CHEN Xi; JIA Yi; GUI XuChun; XU ErYang

    2009-01-01

    As the potential applications of carbon nanotubes in the field of electroluminescence, elements yttrium and europium were introduced to modify the emission properties of double-walled carbon nanotubes (DWNTs) to obtain higher efficacy and other properties. The light emission spectrum of the Y-Eu-doped DWNT filament is suppressed in the near-infrared range, while enhanced in the mid-infrared range. The doped DWNT filament can reach higher efficacy than that of the pure DWNT filament at the same input power and can work stably as long as 5000 h at 12 V. These filaments could be useful for the light sources with special functions, such as infrared light sources operated at low input power.

  19. Spin valve effect of the interfacial spin accumulation in yttrium iron garnet/platinum bilayers

    Science.gov (United States)

    Jin, Lichuan; Zhang, Dainan; Zhang, Huaiwu; Tang, Xiaoli; Bai, Feiming; Zhong, Zhiyong; Fan, Xin; Xiao, John Q.

    2014-09-01

    We report the spin valve effect in yttrium iron garnet/platinum (YIG/Pt) bilayers. The spin Hall effect (SHE) generates spin accumulation at the YIG/Pt interface and can be opened/closed by magnetization switching in the electrical insulator YIG. The interfacial spin accumulation was measured in both YIG/Pt and YIG/Cu/Pt structures using a planar Hall configuration. The spin valve effect remained, even after a 2 nm thick Cu layer was inserted between the YIG and Pt layers, which aimed to exclude the induced magnetization at the YIG/Pt interface. The transverse Hall voltage and switching field were dependent on the applied charge current density. The origin of this behavior can be explained by the SHE induced torque exerted on the domain wall, caused by the transfer of the spin angular momentum from the spin-polarized current to the YIG magnetic moment.

  20. Complete eradication of hepatic metastasis from colorectal cancer by Yttrium-90 SIRT

    Institute of Scientific and Technical Information of China (English)

    Sean Garrean; Amanda Muhs; James T Bui; Michael J Blend; Charles Owens; William S Helton; N Joseph Espat

    2007-01-01

    Yttrium-90 (Y-90) radioembolization, also known as selective internal radiation therapy (SIRT), is a regional hepatic therapy used in the treatment of unresectable colorectal cancer (CRC) liver metastases. In SIRT,Y-90 impregnated microspheres are injected into the VASCULAR SUPPLY of hepatic tumor, leading to selective irradiation and necrosis of tumor TISSUE. While several studies demonstrate improved local control and survival with SIRT, the specific indications for this therapy have yet to be defined. Typically, SIRT is given in combination with chemotherapy as multimodal treatment for unresectable hepatic CRC. However, it HAS ALSO FOUND INCREASING USE as a salvage therapy in chemorefractory patients. Herein, the authors describe their experience with SIRT as "stand alone" therapy in a surgically-prohibitive, chemotherapy naive patient with hepatic CRC metastasis. The results suggest that Y-90 SIRT may have potential applications beyond its usual role as a palliative or salvage therapy for unresectable hepatic CRC.

  1. Complete eradication of hepatic metastasis from colorectal cancer by Yttrium-90 SIRT.

    Science.gov (United States)

    Garrean, Sean; Muhs, Amanda; Bui, James T; Blend, Michael J; Owens, Charles; Helton, William S; Espat, N Joseph

    2007-06-07

    Yttrium-90 (Y-90) radioembolization, also known as selective internal radiation therapy (SIRT), is a regional hepatic therapy used in the treatment of unresectable colorectal cancer (CRC) liver metastases. In SIRT, Y-90 impregnated microspheres are injected into the VASCULAR SUPPLY of hepatic tumor, leading to selective irradiation and necrosis of tumor TISSUE. While several studies demonstrate improved local control and survival with SIRT, the specific indications for this therapy have yet to be defined. Typically, SIRT is given in combination with chemotherapy as multimodal treatment for unresectable hepatic CRC. However, it has also found increasing use as a salvage therapy in chemo-refractory patients. Herein, the authors describe their experience with SIRT as "stand alone" therapy in a surgically-prohibitive, chemotherapy naive patient with hepatic CRC metastasis. The results suggest that Y-90 SIRT may have potential applications beyond its usual role as a palliative or salvage therapy for unresectable hepatic CRC.

  2. Flux-gate magnetic field sensor based on yttrium iron garnet films for magnetocardiography investigations

    Science.gov (United States)

    Vetoshko, P. M.; Gusev, N. A.; Chepurnova, D. A.; Samoilova, E. V.; Syvorotka, I. I.; Syvorotka, I. M.; Zvezdin, A. K.; Korotaeva, A. A.; Belotelov, V. I.

    2016-08-01

    A new type of f lux-gate vector magnetometer based on epitaxial yttrium iron garnet films has been developed and constructed for magnetocardiography (MCG) investigations. The magnetic field sensor can operate at room temperature and measure MCG signals at a distance of about 1 mm from the thoracic cage. The high sensitivity of the sensor, better than 100 fT/Hz1/2, is demonstrated by the results of MCG measurements on rats. The main MCG pattern details and R-peak on a level of 10 pT are observed without temporal averaging, which allows heart rate anomalies to be studied. The proposed magnetic sensors can be effectively used in MCG investigations.

  3. Evidence of dilute ferromagnetism in rare-earth doped yttrium aluminium garnet

    Energy Technology Data Exchange (ETDEWEB)

    Farr, Warrick G.; Goryachev, Maxim; Le Floch, Jean-Michel; Tobar, Michael E. [ARC Centre of Excellence for Engineered Quantum Systems, University of Western Australia, 35 Stirling Highway, Crawley, Western Australia 6009 (Australia); Bushev, Pavel [Experimentalphysik, Universität des Saarlandes, D-66123 Saarbrücken (Germany)

    2015-09-21

    This work demonstrates strong coupling regime between an erbium ion spin ensemble and microwave hybrid cavity-whispering gallery modes in a yttrium aluminium garnet dielectric crystal. Coupling strengths of 220 MHz and mode quality factors in excess of 10{sup 6} are demonstrated. Moreover, the magnetic response of high-Q modes demonstrates behaviour which is unusual for paramagnetic systems. This behaviour includes hysteresis and memory effects. Such qualitative change of the system's magnetic field response is interpreted as a phase transition of rare earth ion impurities. This phenomenon is similar to the phenomenon of dilute ferromagnetism in semiconductors. The clear temperature dependence of the phenomenon is demonstrated.

  4. Bismuth Substituted Yttrium Iron Garnet Single Crystal Films Prepared by Sol-gel Method

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Magneto-optic Faraday rotation effect and the amount of bismuth substituted in yttrium iron garnet single crystal films prepared by gel-coating on modified gadolinium-gallium garnet substrates are investigated, where the gel is synthesized by a sol-gel reaction of nitrates and ethylene glycol. The coated gel is annealed in air at temperatures up to 660℃ for 4h, which is about 300℃ lower than that of liquid-phase epitaxy. The maximum amount of Bi substitution is x=2.7 and the crystallization temperature of garnet phase decreases with the increase of x down to 520℃ for x=2.7. In this film, a huge Faraday rotation of -8.1×104 (°)/cm at λ=0.633μm is obtained.

  5. Energy and average power scalable optical parametric chirped-pulse amplification in yttrium calcium oxyborate.

    Science.gov (United States)

    Liao, Zhi M; Jovanovic, Igor; Ebbers, Chris A; Fei, Yiting; Chai, Bruce

    2006-05-01

    Optical parametric chirped-pulse amplification (OPCPA) in nonlinear crystals has the potential to produce extremes of peak and average power but is limited either in energy by crystal growth issues or in average power by crystal thermo-optic characteristics. Recently, large (7.5 cm diameter x 25 cm length) crystals of yttrium calcium oxyborate (YCOB) have been grown and utilized for high-average-power second-harmonic generation. Further, YCOB has the necessary thermo-optic properties required for scaling OPCPA systems to high peak and average power operation for wavelengths near 1 microm. We report what is believed to be the first use of YCOB for OPCPA. Scalability to higher peak and average power is addressed.

  6. Effect of yttrium on the microstructure of a semi-solid A356 Al alloy

    Institute of Scientific and Technical Information of China (English)

    LIU Zheng; HU Yongmei

    2008-01-01

    The semi-solid slurry of an A356 Al alloy,which was grain-freed by yttrium,was manufactured by low temperature pouring.The effects of grain-refining on the morphology and the grain size of the primary α phase in the semi-solid A356 Al alloy were researched.The results indicate that the semi-solid A356 Al alloy with particle-like and rosette-like primary α-Al can be prepared by low temperature pouring from a liquid grain-refined A356 alloy.The grain size and particle morphology of primary α-Al in the A356 Al alloy are markedly improved by the addition of 0.5 wt.% Y.The fining mechanism of Y on the morphology and grain size of the primary α-Al in the semi-solid A356 Al alloy was delved.

  7. Hydrogen gas sensor based on palladium and yttrium alloy ultrathin film

    Science.gov (United States)

    Yi, Liu; You-ping, Chen; Han, Song; Gang, Zhang

    2012-12-01

    Compared with the other hydrogen sensors, optical fiber hydrogen sensors based on thin films exhibits inherent safety, small volume, immunity to electromagnetic interference, and distributed remote sensing capability, but slower response characteristics. To improve response and recovery rate of the sensors, a novel reflection-type optical fiber hydrogen gas sensor with a 10 nm palladium and yttrium alloy thin film is fabricated. The alloy thin film shows a good hydrogen sensing property for hydrogen-containing atmosphere and a complete restorability for dry air at room temperature. The variation in response value of the sensor linearly increases with increased natural logarithm of hydrogen concentration (ln[H2]). The shortest response time and recovery response time to 4% hydrogen are 6 and 8 s, respectively. The hydrogen sensors based on Pd0.91Y0.09 alloy ultrathin film have potential applications in hydrogen detection and measurement.

  8. Hybrid yttrium iron garnet-ferromagnet structures for spin-wave devices

    Energy Technology Data Exchange (ETDEWEB)

    Papp, A., E-mail: apapp@nd.edu [Center for Nano Science and Technology and Department of Electrical Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States); Pázmány Péter Catholic University, Faculty of Information Technology, Budapest 1088 (Hungary); Porod, W., E-mail: porod@nd.edu; Csaba, G., E-mail: gcsaba@nd.edu [Center for Nano Science and Technology and Department of Electrical Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States)

    2015-05-07

    We study coupled ferromagnetic layers, which could facilitate low loss, sub 100 nm wavelength spin-wave propagation and manipulation. One of the layers is a low-loss garnet film (such as yttrium iron garnet (YIG)) that enables long-distance, coherent spin-wave propagation. The other layer is made of metal-based (Permalloy, Co, and CoFe) magnetoelectronic structures that can be used to generate, manipulate, and detect the spin waves. Using micromagnetic simulations, we analyze the interactions between the spin waves in the YIG and the metallic nanomagnet structures and demonstrate the components of a scalable spin-wave based signal processing device. We argue that such hybrid-metallic ferromagnet structures can be the basis of potentially high-performance, ultra low-power computing devices.

  9. Investigation of nanostructural, thermal and magnetic properties of yttrium iron garnet synthesized by mechanochemical method

    Science.gov (United States)

    Karami, M. A.; Shokrollahi, H.; Hashemi, B.

    2012-09-01

    This paper focuses on the magnetic, structural and thermal properties of mechanically alloyed Y2O3/α-Fe2O3 mixed powders and investigates the effects of the mechanical milling and heat treatment on the synthesis of yttrium iron garnet from the primary materials. The morphological and structural studies were carried out by scanning electron microscope and X-ray diffraction, respectively. The thermal activities were measured by differential thermal analysis. The magnetic properties were studied by vibrating sample magnetometer. The results showed that high-energy milling does not lead to the garnet formation and even does not decrease the temperature of the garnet formation. Furthermore, the orthoferrite phase can be achieved slightly during the milling process (up to 96 h) and completely by the heat treatment at lower temperatures (850 °C).

  10. Phase Analysis of Cemented Carbide WC—Co Boronised with Yttrium

    Institute of Scientific and Technical Information of China (English)

    刘寿荣; 郝建民; 等

    2002-01-01

    Phase analysis for the coated surface with B4Cand Y2O3of cemented carbide WC-20Co in vacuum-heating was carried out by high-temperature X-ray diffraction from ambient temperature to 1300℃,The results show that,the high-concentration active boron atoms are released from the boron-supply agent B4Clocated on the alloy surface and diffused into the γphase,leading to forming the three-element boron-bearing compound W2Co21B6beside forming boron-bearins compounds on the blank surface.By contrast with boronising only,the element yttrium in boronization broadens the boronising temperature range during vacuum-sistering,catalyzes the decarbonisation decomposition of B4C and promotes diffusion of active boron atoms into the bulk of WC-Co.

  11. Phase Analysis of Cemented Carbide WC-Co Boronised with Yttrium

    Institute of Scientific and Technical Information of China (English)

    刘寿荣; 郝建民; 褚连青; 宋俊亭

    2002-01-01

    Phase analysis for the coated surface with B4C and Y2O3 of cemented carbid e WC-20Co in vacuum-heating was carried out by high-temperature X-ray diffra ction from ambient temperature to 1300 ℃. The results show that, the high-conc entration active boron atoms are released from the boron-supply agent B4C loc ated on the alloy surface and diffused into the γ-phase, leading to forming th e three-element boron-bearing compound W2Co21B6 beside forming boron -bearing compounds on the blank surface. By contrast with boronising only, the element yttrium in boronization broadens the boronising temperature range during vacuum-sintering, catalyzes the decarbonisation decomposition of B4C and prom otes diffusion of active boron atoms into the bulk of WC-Co.

  12. Nonlinear dynamics of three-magnon process driven by ferromagnetic resonance in yttrium iron garnet

    Energy Technology Data Exchange (ETDEWEB)

    Cunha, R. O. [Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE (Brazil); Centro Interdisciplinar de Ciências da Natureza, Universidade Federal da Integração Latino-Americana, 85867-970 Foz do Iguaçu, PR (Brazil); Holanda, J.; Azevedo, A.; Rezende, S. M., E-mail: rezende@df.ufpe.br [Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE (Brazil); Vilela-Leão, L. H. [Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE (Brazil); Centro Acadêmico do Agreste, Universidade Federal de Pernambuco, 55002-970 Caruaru, PE (Brazil); Rodríguez-Suárez, R. L. [Facultad de Física, Pontificia Universidad Católica de Chile, Casilla 306, Santiago (Chile)

    2015-05-11

    We report an investigation of the dynamics of the three-magnon splitting process associated with the ferromagnetic resonance (FMR) in films of the insulating ferrimagnet yttrium iron garnet (YIG). The experiments are performed with a 6 μm thick YIG film close to a microstrip line fed by a microwave generator operating in the 2–6 GHz range. The magnetization precession is driven by the microwave rf magnetic field perpendicular to the static magnetic field, and its dynamics is observed by monitoring the amplitude of the FMR absorption peak. The time evolution of the amplitude reveals that if the frequency is lowered below a critical value of 3.3 GHz, the FMR mode pumps two magnons with opposite wave vectors that react back on the FMR, resulting in a nonlinear dynamics of the magnetization. The results are explained by a model with coupled nonlinear equations describing the time evolution of the magnon modes.

  13. Chemical solution deposition of ferroelectric yttrium-doped hafnium oxide films on platinum electrodes

    Science.gov (United States)

    Starschich, S.; Griesche, D.; Schneller, T.; Waser, R.; Böttger, U.

    2014-05-01

    Ferroelectric hafnium oxide films were fabricated by chemical solution deposition with a remnant polarization of >13 μC/cm2. The samples were prepared with 5.2 mol. % yttrium-doping and the thickness varied from 18 nm to 70 nm. The hafnium oxide layer was integrated into a metal-insulator-metal capacitor using platinum electrodes. Due to the processing procedure, no thickness dependence of the ferroelectric properties was observed. To confirm the ferroelectric nature of the deposited samples, polarization, capacitance, and piezoelectric displacement measurements were performed. However, no evidence of the orthorhombic phase was found which has been proposed to be the non-centrosymmetric, ferroelectric phase in HfO2.

  14. Valence Control of Ce Ions in Cerium-substituted Yttrium Iron Garnet

    Institute of Scientific and Technical Information of China (English)

    SONG Fengbing; LI Qiang; ZHONG Zhifeng

    2005-01-01

    Cerium-substituted yttrium iron garnet(CexY3-xFe5O12, Ce∶YIG) was prepared via coprecipitation. The structure, morphology, valence state and constituent of Ce ions were investigated respectively. X-ray powder diffraction(XRD) analysis shows that Ce∶YIG was of single cubic YIG phase. The result of X-ray photoelectron spectroscopy(XPS) indicates the Ce ions in Ce∶YIG were in the state of trivalence. Scanning electron microscope(SEM) demonstrates the conglobation of Ce∶YIG particles about 0.2μm scale.The magnetic properties were studied by a vibrating sample magnetometer(VSM) and the result exhibits that substitution of Ce3+ changes the magnetic parameters of YIG. The effects of doping content of Ce ions and synthesis temperature on valence control were discussed in detail.

  15. Thermo-transferred thermoluminescence (TTTl) in potassium-yttrium double fluoride doped with terbium

    Energy Technology Data Exchange (ETDEWEB)

    Gallegos, A.; Rivera, T.; Diaz G, J. A. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Legaria 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico); Azorin, J. [Universidad Autonoma Metropolitana, Unidad Iztapalapa, San Rafael Atlixco No. 186, Col. Vicentina, 09340 Mexico D. F. (Mexico); Azorin, J. C. [Universidad de Guanajuato, Division de Ciencias e Ingenierias-Campus Leon, Lomas del Bosque No. 103, Col. Lomas del Campestre, 37000 Leon, Guanajuato (Mexico); Licona, R.; Rivas, F.; Hernandez C, G. [Benemerita Universidad Autonoma de Puebla, Facultad de Ciencias Quimicas, 14 Sur y San Claudio, Ciudad Universitaria, Puebla de Zaragoza, Puebla (Mexico); Khaidukov, N. [Institute of General and Inorganic Chemistry, Lenin SK 11 Prospect 31, Moscow 117907 (Russian Federation)

    2011-02-15

    This paper presents results of studying the thermo-transferred thermoluminescence (TTTl) phenomenon in potassium-yttrium double fluoride doped with terbium (K{sub 2}YF{sub 5:}Tb) at different impurity concentrations (0.8%, 0.95% and 0.99%). Previously to study the TTTl phenomenon, structural characterization and chemical composition of the materials were determined. The structural studies were conducted using a scanning electron microscope; meanwhile, chemical composition was analyzed using energy dispersive X-ray spectroscopy. Thermoluminescence kinetics was studied irradiating the samples with {sup 137}Cs gamma rays as well as with {sup 90}Sr/{sup 90}Y beta rays, analyzing the glow curves by the deconvolution method for obtaining the kinetic parameters. (Author)

  16. Luminescent Properties of Eu3+-Doped Yttrium Oxide Chloride Embedded in Nanoporous Glass

    Institute of Scientific and Technical Information of China (English)

    曾小青; 林凤英; 干福熹; 袁绥华

    2002-01-01

    The photoluminescence of Eu3+-doped yttrium oxide chloride embedded in nanoporous glass has been observed. In comparison with those in the powder phosphor, the emission lines of Eu3+ ions become much broader and blueshift was observed in the lines due to 5D0 → 7F2 transitions and the Eu-O charge transfer excitation band. The ratio intensities of the 5 D0 → 7 F1 transitions to the 5Do → 7 F2 transitions of Eu3+ ion become higher and change at different excitation wavelengths, such as 393nm and 254nm. The two excitation wavelengths belong to the 4f → 4f transition of the Eus+ ion and the Eu-O charge transfer, respectively. This material may be developed into a new luminescent glass.

  17. Structural and electrical studies of sol-gel synthesized nanocrystalline hexagonal yttrium iron manganite ceramics

    Science.gov (United States)

    Touthang, Jangkhohao; Maisnam, Mamata

    2017-03-01

    Hexagonal yttrium manganites, YMnO3, are interesting materials for their multiferroic behavior. Substituting suitable cations either at the Y-site or Mn-site offers great opportunities to produce a variety of manganites and tune their properties. Nanocrystalline yttrium iron manganites with the compositional formula Y1‑xFexMnO3, x = 0.0, 0.10, 0.15, 0.20 and 0.25, were synthesized by sol-gel autocombustion method. The prepared samples were heated at 1100∘C for 1 h. Another set of samples with compositional formula YFexMn1‑xO3, x = 0.0, 0.10, 0.15, 0.20 and 0.25, were also synthesized by the same method and heated at 1100∘C for 1 h. Various characterizations were done on these manganite systems synthesized by substituting iron at different sites. X-ray diffraction (XRD) technique studied the structure of the samples and analysis of XRD patterns confirmed the formation of hexagonal phase in the samples. Structural parameters such as lattice constants, crystallite size, theoretical density, etc. were determined using the XRD data. The unit cell dimensions have been found to agree with the standard data and the Debye-Scherrer crystallite size obtained from XRD data ranges from 42 nm to 77 nm. The room temperature frequency variations of electrical properties such as dielectric constant, dielectric loss and AC conductivity were measured in the range of 100 Hz-2 MHz and the variations showed a dispersive behavior for all the samples. The various measurements and the results obtained were studied and discussed in the paper.

  18. Availability of yttrium-90 from strontium-90: a nuclear medicine perspective.

    Science.gov (United States)

    Chakravarty, Rubel; Dash, Ashutosh; Pillai, M R A

    2012-12-01

    Yttrium-90 (T(½) 64.1 hours, E(βmax)=2.28 MeV) is a pure β⁻ particle emitting radionuclide with well-established applications in targeted therapy. There are several advantages of ⁹⁰Y as a therapeutic radionuclide. It has a suitable physical half-life (∼64 hours) and decays to a stable daughter product ⁹⁰Zr by emission of high-energy β⁻ particles. Yttrium has a relatively simple chemistry and its suitability for forming complexes with a variety of chelating agents is well established. The ⁹⁰Sr/⁹⁰Y generator is an ideal source for the long-term continuous availability of no-carrier-added ⁹⁰Y suitable for the preparation of radiopharmaceuticals for radionuclide therapy. The parent radionuclide ⁹⁰Sr, which is a long-lived fission product, is available in large quantities from spent fuel. Several useful technologies have been developed for the preparation of ⁹⁰Sr/⁹⁰Y generators. There are several well-established radiopharmaceuticals based on monoclonal antibodies, peptides, and particulates labeled with ⁹⁰Y, that are in regular use for the treatment of some forms of primary cancers and arthritis. At present, there are no generators for the elution of ⁹⁰Y that can be set up in a hospital radiopharmacy. The radionuclide is procured from manufacturers and the radiopharmaceuticals are formulated on site. This article reviews the development of ⁹⁰Sr/⁹⁰Y generator and the development of ⁹⁰Y radiopharmaceuticals.

  19. Development of Alcoa aluminum foam products

    Energy Technology Data Exchange (ETDEWEB)

    Bryant, J.D.; Crowley, M.D.; Wang, W.; Wilhelmy, D.M.; Hunter, D.E. [Alcoa Technical Center, Alcoa Center, PA (United States)

    2007-07-01

    A new lightweight aluminum foam product was described. The foam was made through the controlled decomposition of carbonate powders within molten aluminum and was able to resist both coalescence and drainage. The fine-celled aluminum foam derived its physical and mechanical properties from the properties of the aluminum alloy matrix from which they were produced. The rheology of the molten aluminum was modified to provide a superior mesostructure. Stabilization was achieved by creating a solid-gas-liquid suspension initiated by the addition of carbonates into an aluminum alloy melt. A cascade of chemical reactions then occurred within the melt to create a foamable suspension. Carbon monoxide (CO) was generated to initiate an additional sequence of chemical reactions which resulted in the formation of solid particles within the liquid metal. CO reacted with liquid Al to form graphite. The graphite then reacted with Al to form aluminum carbide (Al{sub 4}C{sub 3}). The microstructural, mesostructural, and mechanical character of the foams produced under different processing conditions were examined. Details of experimental test procedures were also described. It was concluded that the specific crush energy absorption was as high as 20 kJ/kg. The foam exhibited a bending stiffness that was approximately 20 to 30 times higher than balsa and polymer foams. 14 refs., 2 tabs., 7 figs.

  20. Lead exposure from aluminum cookware in Cameroon

    Energy Technology Data Exchange (ETDEWEB)

    Weidenhamer, Jeffrey D.; Kobunski, Peter A. [Department of Chemistry, Geology and Physics, 401 College Ave., Ashland University, Ashland, OH 44805 (United States); Kuepouo, Gilbert [Research and Education Centre for Development (CREPD), Yaounde (Cameroon); Corbin, Rebecca W. [Department of Chemistry, Geology and Physics, 401 College Ave., Ashland University, Ashland, OH 44805 (United States); Gottesfeld, Perry, E-mail: pgottesfeld@okinternational.org [Occupational Knowledge International, San Francisco, CA (United States)

    2014-10-15

    Blood lead levels have decreased following the removal of lead from gasoline in most of the world. However, numerous recent studies provide evidence that elevated blood lead levels persist in many low and middle-income countries around the world at much higher prevalence than in the more developed countries. One potential source of lead exposure that has not been widely investigated is the leaching of lead from artisanal aluminum cookware, which is commonly used in the developing world. Twenty-nine samples of aluminum cookware and utensils manufactured by local artisans in Cameroon were collected and analyzed for their potential to release lead during cooking. Source materials for this cookware included scrap metal such as engine parts, radiators, cans, and construction materials. The lead content of this cookware is relatively low (< 1000 ppm by X-ray fluorescence), however significant amounts of lead, as well as aluminum and cadmium were released from many of the samples using dilute acetic acid extractions at boiling and ambient temperatures. Potential exposures to lead per serving were estimated to be as high as 260 μg, indicating that such cookware can pose a serious health hazard. We conclude that lead, aluminum and cadmium can migrate from this aluminum cookware during cooking and enter food at levels exceeding recommended public health guidelines. Our results support the need to regulate lead content of materials used to manufacture these pots. Artisanal aluminum cookware may be a major contributor to lead poisoning throughout the developing world. Testing of aluminum cookware in other developing countries is warranted. - Highlights: • Cookware is manufactured in Cameroon from scrap aluminum including car parts. • Twenty-nine cookware samples were evaluated for their potential to leach lead. • Boiling extractions to simulate the effects of cooking released significant lead. • Potential lead exposures per serving are estimated as high as 260 μg.

  1. Fatigue analysis of aluminum drill pipes

    Directory of Open Access Journals (Sweden)

    João Carlos Ribeiro Plácido

    2005-12-01

    Full Text Available An experimental program was performed to investigate the fundamental fatigue mechanisms of aluminum drill pipes. Initially, the fatigue properties were determined through small-scale tests performed in an optic-mechanical fatigue apparatus. Additionally, full-scale fatigue tests were carried out with three aluminum drill pipe specimens under combined loading of cyclic bending and constant axial tension. Finally, a finite element model was developed to simulate the stress field along the aluminum drill pipe during the fatigue tests and to estimate the stress concentration factors inside the tool joints. By this way, it was possible to estimate the stress values in regions not monitored during the fatigue tests.

  2. Nanshan Aluminum Reached Strategic Cooperation with CSR Corporation Limited

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    As a key supplier of aluminum profiles and aluminum plate,sheet and trip products for CSR Corporation Limited,Nanshan Aluminum will join hands with CSR Corporation Limited to reach strategic cooperation.On January 5,Nanshan Aluminum signed strategic cooperation agreement with CSR Sifang Locomotive&Rolling; Stock Co.,Ltd,both

  3. Changes in porosity of foamed aluminum during solidification

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In order to control the porosity of foamed aluminum, the changes in the porosity of foamed aluminum melt in the processes of foaming and solidification, the distribution of the porosity of foamed aluminum, and the relationship between them were studied. The results indicated that the porosity of foamed aluminum coincides well with the foaming time.

  4. Coordination Structure of Aluminum in Magnesium Aluminum Hydroxide Studied by 27Al NMR

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The coordination structure of aluminum in magnesium aluminum hydroxide was studiedby 27Al NMR. The result showed that tetrahedral aluminum (AlⅣ) existed in magnesiumaluminum hydroxide, and the contents of AlⅣ increased with the increase of the ratio of Al/Mg andwith the peptizing temperature. AlⅣ originated from the so-called Al13 polymer with the structureof one Al tetrahedron surrounded by twelve Al octahedrons.

  5. Influence of cyclic frequency on oxidation behavior of K38 superalloy with yttrium additions at 1 273 K

    Institute of Scientific and Technical Information of China (English)

    YU Ping; WANG Wen; WANG Fuhui

    2011-01-01

    Cyclic oxidation test is a fundamental method to assess lifetime of materials in high temperature environment. Cycle length or cyclic frequency is one important variable in cyclic oxidation testing. In present work, cyclic oxidation tests were performed on cast K38 alloys with 0 wt.%, 0.1 wt.%, and 0.5 wt.% yttrium additions at 1 273 K respectively. Two cyclic frequencies were used to investigate the influence of cycle length (1 h vs. 20 h) on the high temperature oxidation behavior of superalloy. The results showed that the degradation of cast K38alloy critically was dependent on the cyclic frequency. The yttrium addition was beneficial to reducing scale-growth rate, improving the scale adhesion and stress releasing, thereby increased the spallation resistance. It could be drawn that the effect of cyclic frequency was highly dependent on the scale adherence to the substrate.

  6. Microstructural characteristics and second-phase particles in yttrium-bearing Fe-10Ni-7Mn martensitic steels

    Institute of Scientific and Technical Information of China (English)

    F. Forghani; M. Nili-Ahmadabadi

    2014-01-01

    In this study, the microstructure and second-phase particles in yttrium (0.05 wt.%and 0.8 wt.%) bearing Fe-10Ni-7Mn steels were characterized. The results of X-ray analysis as well as scanning electron microscopy coupled with energy dispersive X-ray spectroscopy indicated the formation of (Fe, Ni, Mn)17Y2 precipitates with hexagonal structure in a Fe-10Ni-7Mn-0.8Y (wt.%) alloy. Lattice parameters of these precipitates were calculated as follows:a=0.8485 nm and c=0.8274 nm. Formation of Y2O3 sub-micron particles was also confirmed in both yttrium bearing steels via electrolytic phase extraction method. The effect of these precipitates on the prior austenite grain size was investigated. The results revealed that these precipitates had an effective role in controlling the prior austenite grain size.

  7. The Influence of Yttrium Isopropoxide on the Mechanical Properties of SiCW-reinforced AlN Ceramics

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    By using self-made metal-alkoxide yttrium isopropoxide as a sintering additive and disperser of whisker,the SiC whisker reinforced AlN ceramics was prepared.Its apparent density is 99.5 percent of the theoretical density;its flexural strength and fracture toughness are 681 MPa and 5.21 MPa*m1/2 respectively.Comparing the result with that by applying Y2O3 powder as a sintering additive,the flexural strength is increased by 25% and the fracture toughness is increased by 33%.The dispersity of whisker by increased yttrium isopropoxide is significantly better than that by Triton X-100.

  8. South West Aluminum: Next year The Capacity of Auto-use Aluminum Sheet will Reach 5000 Tonnes

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    Following supplying supporting aluminum products for"Shenzhou"spacecraft,"Long March"rocket,Boeing and Airbus,South West Aluminum again tapped new economic growth points,i.e.automobile-use aluminum products.According to what the reporter has learned from South West Aluminum Group recently,this group has finished early stage

  9. Aluminum recovery as a product with high added value using aluminum hazardous waste.

    Science.gov (United States)

    David, E; Kopac, J

    2013-10-15

    The samples of hazardous aluminum solid waste such as dross were physically and chemically characterized. A relationship between density, porosity and metal content of dross was established. The paper also examines the chemical reactions involving aluminum dross in landfill and the negative consequences. To avoid environmental problems and to recovery the aluminum, a processing method was developed and aluminum was recovered as an added value product such as alumina. This method refers to a process at low temperature, in more stages: acid leaching, purification, precipitation and calcination. At the end of this process aluminum was extracted, first as Al(3+) soluble ions and final as alumina product. The composition of the aluminum dross and alumina powder obtained were measured by applying the leaching tests, using atomic absorption spectrometry (AAS) and chemical analysis. The mineralogical composition of aluminum dross samples and alumina product were determined by X-ray diffraction (XRD) and the morphological characterization was performed by scanning electron microscopy (SEM). The method presented in this work allows the use of hazardous aluminum solid waste as raw material to recover an important fraction from soluble aluminum content as an added value product, alumina, with high grade purity (99.28%).

  10. Preliminary Study on Aluminum Content of Foods and Aluminum Intake of Residents in Tianjin

    Institute of Scientific and Technical Information of China (English)

    XUGe-Sheng; JINRng-Pei; 等

    1993-01-01

    Aluminum contents of 64 kinds of foods in Tianjin were detrmined.The results showed that the aluminum levels in diffeent kinds of foods varied greatly,and most foodstuffs from natural sources(including contamination from food processing)contained less than 10mg/kg,Aluminum contents were higher in foodstuffs of plant origin,especiallydry beans containing large amounts of aluminum naturally.Lower concentration of aluminum seemed to be present in foodstuffs of animal origin.It was estimated that the potential daily intake of aluminum per person from natural dietary sources in Tianjin was about 3.79 mg.This estimated figure of dietary aluminum intake was very close to the measured data from 24 daily diets of college students.which was 4.86±1.72mg.Considering all the potential sources of natural aluminum in foods.water and the individual habitual food,it would apear that most residents in Tianjin would consume 3-10mg aluminum daily from natural dietary sources.

  11. Southwest Aluminum Increase Two Production Lines and May Become the Largest Aluminum Fabricator In the World

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    <正>Recently,Wu Bing,Director of Chongqing Economic Committee,announced at the"Industrial Economy Meeting"that the city will"facilitate the technical upgrade and capacity expansion of the existing production lines at Southwest Aluminum with great efforts on the construction of one additional hot continuous rolling line and one cold continuous rolling line so as to have a comprehensive production ca- pacity of 1.2 million tons on aluminum processing profiles for the achievement of building Southwest Aluminum into the world largest aluminum processing enterprise".

  12. Over-heated Investment in Aluminum Hub Industry

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>Aluminum hub is one of typical products with the comparative advantages.China’s aluminum hub industry is very competitive.In recent years,the value of export for the aluminum hub soared,increasing from USD130 millions in 1999 up to nearly USD1 billion in 2004.The main exporter are Wanfeng Auto Holding Group,Shanghai Fervent Alloy Wheel MFG Co.,Ltd.,Nanhai Zhongnan Aluminum Co., Ltd.,Taian Huatai Aluminum Hub Co.,Ltd.

  13. Aluminum-CNF Lightweight Radiator Components Project

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal relates to a new materials concept for an aluminum-carbon nanofiber composite, high thermal conductivity ultra lightweight material that will form the...

  14. Profit of Aluminum Industry Dropped Sharply

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>On August 2nd,the Ministry of Industry and Information Technology published the performance of nonferrous metal industry in the first half of 2011.Relevant data showed that due to cost increase,aluminum smelting enter

  15. Inhibition of aluminum corrosion using Opuntia extract

    Energy Technology Data Exchange (ETDEWEB)

    El-Etre, A.Y

    2003-11-01

    The inhibitive action of the mucilage extracted from the modified stems of prickly pears, toward acid corrosion of aluminum, is tested using weight loss, thermometry, hydrogen evolution and polarization techniques. It was found that the extract acts as a good corrosion inhibitor for aluminum corrosion in 2.0 M HCl solution. The inhibition action of the extract was discussed in view of Langmuir adsorption isotherm. It was found that the adsorption of the extract on aluminum surface is a spontaneous process. The inhibition efficiency (IE) increases as the extract concentration is increased. The effect of temperature on the IE was studied. It was found that the presence of extract increases the activation energy of the corrosion reaction. Moreover, the thermodynamic parameters of the adsorption process were calculated. It was found also that the Opuntia extract provides a good protection to aluminum against pitting corrosion in chloride ion containing solutions.

  16. Aluminum plasmonic multicolor meta-hologram.

    Science.gov (United States)

    Huang, Yao-Wei; Chen, Wei Ting; Tsai, Wei-Yi; Wu, Pin Chieh; Wang, Chih-Ming; Sun, Greg; Tsai, Din Ping

    2015-05-13

    We report a phase-modulated multicolor meta-hologram (MCMH) that is polarization-dependent and capable of producing images in three primary colors. The MCMH structure is made of aluminum nanorods that are arranged in a two-dimensional array of pixels with surface plasmon resonances in red, green, and blue. The aluminum nanorod array is patterned on a 30 nm thick SiO2 spacer layer sputtered on top of a 130 nm thick aluminum mirror. With proper design of the structure, we obtain resonances of narrow bandwidths to allow for implementation of the multicolor scheme. Taking into account of the wavelength dependence of the diffraction angle, we can project images to specific locations with predetermined size and order. With tuning of aluminum nanorod size, we demonstrate that the image color can be continuously varied across the visible spectrum.

  17. Masking of aluminum surface against anodizing

    Science.gov (United States)

    Crawford, G. B.; Thompson, R. E.

    1969-01-01

    Masking material and a thickening agent preserve limited unanodized areas when aluminum surfaces are anodized with chromic acid. For protection of large areas it combines well with a certain self-adhesive plastic tape.

  18. Shock wave compression behavior of aluminum foam

    Institute of Scientific and Technical Information of China (English)

    程和法; 黄笑梅; 薛国宪; 韩福生

    2003-01-01

    The shock wave compression behavior of the open cell aluminum foam with relative density of 0. 396 was studied through planar impact experiments. Using polyvinylidene fluoride(PVDF) piezoelectric gauge technique, the stress histories and propagation velocities of shock wave in the aluminum foam were measured and analyzed. The results show that the amplitude of shock wave attenuates rapidly with increasing the propagation distance in the aluminum foam, and an exponential equation of the normalized peak stress vs propagation distance of shock wave is established, the attenuation factor in the equation is 0. 286. Furthermore, the Hugoniot relation, νs = 516.85+ 1.27νp,for the aluminum foam is determined by empirical fit to the experimental Hugoniot data.

  19. China Aluminum Processing Industry Development Report 2011

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    <正>In 2011,China’s aluminum processing industry maintained a high growth rate,with the aluminum output reaching 23,456,000tons,up 20.6% y-o-y.Overshadowed by complicated situation both at home and abroad,China’seconomy slowed down and declined by2.2% y-o-y.In 2011,China’s aluminum processing industry showed a downward tendency,that is,it grew at a high speed before the3rd quarter,but suffered from a shortage of orders in the remaining time of the year and the growth rate fell increasingly.Between January and August,China’s aluminum output rose by 26% y-o-y;

  20. Er:YAG激光治疗对牙髓的作用%Effects of Erbium:Yttrium-Aluminum-Garnet (Er:YAG) Laser on Dental Pulp

    Institute of Scientific and Technical Information of China (English)

    郭怡丹; 张笋

    2013-01-01

    Er:YAG激光作为第一种被美国食品药品监管总局批准用于口腔硬组织的激光,以其高效、无痛和对牙髓组织损伤小等特点越来越受到人们的关注.Er:YAG激光在对恒牙和乳牙备洞及直接作用于牙髓时,产生的热效应小,不会给牙髓组织带来不可逆损伤.还可以降低炎症反应程度,促进牙本质桥的快速生成.%With many advantages such as painlessness,low thermal effects and effective cutting of enamel and dentin without damaging the pulp,Er:YAG laser,the first type of the lasers approved to treat hard dental tissues by FDA in 1997,has gained more and more attention in handling dental diseases.It will not cause irreversible damage by virtue of its low thermal effect when used for permanent or primary tooth cavity preparation or on pulp directly.Furthermore,the inflammation response can be weakened and the formation of reparative dentin accelerated with Er:YAG laser.

  1. Effect of Gallium and Indium Co-Substituting on Upconversion Properties of Er/Yb:Yttrium Aluminum Garnet Powders Prepared by the Co-Precipitation Method.

    Science.gov (United States)

    Zhang, Wei; Liang, Yun-Ling; Hu, Zheng-Fa; Feng, Zu-Yong; Lun, Ma; Zhang, Xiu-ping; Sheng, Xia; Liu, Qian; Luo, Jie

    2016-04-01

    Gallium and Indium co-substituted Yb, Er:YAG was fabricated through the chemical co-precipitation method. The formation process and structure of the Ga3+ and In3+ substituted phosphor powders were characterized by the X-ray diffraction, thermo-gravimetry analyzer, infrared spectra, and X-ray photoelectron spectroscopy, and the effects of Ga3+ and In3+ concentration on the luminescence properties were investigated by spectrum. The results showed that the blue shift occurred after the substitution of Ga3+ and In3+ for Al3+ in matrix, and the intensity of emission spectrum was affected by the concentration of Ga3+ and In3+.

  2. Efficiency of ablative fractional Er: YAG (Erbium: Yttrium-Aluminum-Garnet laser treatment of epidermal and dermal benign skin lesions: A retrospective study

    Directory of Open Access Journals (Sweden)

    Erol Koç

    2014-03-01

    Full Text Available Background: Er: YAG lasers are precise ablation systems used in the treatment epidermal and dermal benign skin lesions. In this study, we restrospectively analysed efficiency of Er: YAG laser therapy in the treatment of epidermal and dermal benign skin lesions. Materials and Methods: We retrospectively investigated our clinical records of 116 patients treated with Er: YAG laser between April 2011 and April 2013. The clinical records of 103 patients (47 men, 56 women were included in our study. Of these 103 patients included in the study were xanthelasma, solar lentigo, epidermal nevus, seborrheic keratosis, nevus of ota, syringoma, cafe au lait macules (CALM and other than these. Treatment parameters, demographic features and before and after photographs of the lesions were investigated from patients’ records in order to evaluate efficiency of Er: YAG laser therapy. Results: Of these 103 patients included in the study were evaluated in 8 groups, described as xanthelasma (n=21, syringoma (n=17, solar lentigo (n=16, epidermal nevus (n=11, seborrheic keratosis (n=9, nevus of ota (n=5, CALM (n=3 and other than these (n=21. In the Er: YAG laser treatment, the average energy flow was 3-7 J/cm2, the average pulse duration was 300 ms, the average number of passes was 3-5 repeat, and the average pulse frequency was 3-7 Hz. While 4.9% of the patients showed no improvement, 59.2% showed marked improvement, 26.2% showed moderate improvement and 9.7% showed mild improvement. Treatment responses in xanthelasma, syringoma, epidermal nevus, solar lentigo and CALM lesions were statistically significant. Observed side effects were hyperpigmentation in 4 patients, hypopigmentation in 3 patients, hypertrophic scar in 2 patients and persistent erythema in one patient and the treatment was well tolerated by all the patients. Conclusion: Er: YAG laser is an effective and safe treatment option in the treatment of benign skin lesions especially in epidermal lesions.

  3. Coupling of erbium dopants to yttrium orthosilicate photonic crystal cavities for on-chip optical quantum memories

    CERN Document Server

    Miyazono, Evan; Craiciu, Ioana; Kindem, Jonathan M; Faraon, Andrei

    2016-01-01

    Erbium dopants in crystals exhibit highly coherent optical transitions well suited for solid-state optical quantum memories operating in the telecom band. Here we demonstrate coupling of erbium dopant ions in yttrium orthosilicate to a photonic crystal cavity fabricated directly in the host crystal using focused ion beam milling. The coupling leads to reduction of the photoluminescence lifetime and enhancement of the optical depth in microns-long devices, which will enable on-chip quantum memories.

  4. Separation of yttrium (III) from lanthanoids (III) by solvent extraction with substituted N-Alkylcarbonyl-N-phenylhydroxylamines

    Energy Technology Data Exchange (ETDEWEB)

    Haraguchi, K.; Ogata, T.; Nakagawa, K. [Hokkaido National Industrial Research Institute, Sapporo (Japan); Saitoh, T.; Kamidate, T.; Watanabe, H. [Hokkaido University, Sapporo, (Japan). Faculty of Engineering

    1996-12-31

    A series of substituted N-alkylcarbonyl-N-phenylhydroxylamines(R-PHAs) were synthesized and utilized for the extraction of yttrium(III) and lanthanoids(III) in order to obtain effective extractants for the separation of yttrium(III) from the lanthanoids(III) and the mutual separation of the lanthanoids(III). The distribution ratio of yttrium(III) and the lanthanoids(III) between the carbon tetrachloride and the aqueous phases was measured as functions of the pH and the extractant concentration at 298 K at an ionic strength of 0.1 (NaNO{sub 3}). Yttrium(III) and the lanthanoids(III) were extracted with R-PHAs(HL) as self-adducted chelates of the form, ML{sub 3}(HL){sub x}, where `x` is 1, 2 or 3 depending on the extraction system. The extractability of the metal ions decreased in the order of R-PHA having a primary, a secondary and a tertiary alkyl substituent attached to the carbonyl group because of the steric hindrance of the alkyl group. The separation factors for both Yb/Eu and Yb/Y pairs increased with increasing branching of the alkyl group of R-PHA. The excellent selectivity of R-PHAs having a tertiary alkyl group was attributable to a greater inductive effect of the tertiary alkyl group than those of the primary and secondary alkyl groups. The substituents at the phenyl group of R-PHAs gave no significant effect on the selectivity, while the extractability was enhanced considerably by introduction of electron withdrawing substituents at appropriate positions of the phenyl group of R-PHAs. (authors) 10 refs., 3 tabs., 1 fig.

  5. Bonding mechanism of a yttrium iron garnet film on Si without the use of an intermediate layer

    Energy Technology Data Exchange (ETDEWEB)

    Pantzas, Konstantinos, E-mail: konstantinos.pantzas@lpn.cnrs.fr [CNRS-LPN, Route de Nozay, F-91460 Marcoussis (France); Institut P' , CNRS-Université de Poitiers - ENSMA - UPR 3346, SP2MI - Téléport 2 Bd Marie Pierre Curie, B.P. 30179, F-86962, Futuroscope Chasseneuil Cedex (France); Patriarche, Gilles; Talneau, Anne [CNRS-LPN, Route de Nozay, F-91460 Marcoussis (France); Youssef, Jamal Ben [Laboratoire de Magnetisme de Bretagne, 6 avenue Le Gorgeu, 29238 Brest Cedex 3 (France)

    2014-10-06

    Direct bonding of yttrium iron garnet (YIG) on silicon without the use of an intermediate bonding layer is demonstrated and characterized using scanning transmission electron microscopy and energy-dispersive x-ray spectroscopy. During the bonding experiment, the garnet is reduced in the presence of oxide-free silicon. As a result, a 5 nm thick SiO{sub 2}/amorphous-YIG bilayer is formed and welds the garnet to silicon.

  6. Coupling of erbium dopants to yttrium orthosilicate photonic crystal cavities for on-chip optical quantum memories

    Energy Technology Data Exchange (ETDEWEB)

    Miyazono, Evan; Zhong, Tian; Craiciu, Ioana; Kindem, Jonathan M.; Faraon, Andrei, E-mail: faraon@caltech.edu [T. J. Watson Laboratory of Applied Physics, California Institute of Technology, 1200 E California Blvd, Pasadena, California 91125 (United States)

    2016-01-04

    Erbium dopants in crystals exhibit highly coherent optical transitions well suited for solid-state optical quantum memories operating in the telecom band. Here, we demonstrate coupling of erbium dopant ions in yttrium orthosilicate to a photonic crystal cavity fabricated directly in the host crystal using focused ion beam milling. The coupling leads to reduction of the photoluminescence lifetime and enhancement of the optical depth in microns-long devices, which will enable on-chip quantum memories.

  7. Advanced powder metallurgy aluminum alloys and composites

    Science.gov (United States)

    Lisagor, W. B.; Stein, B. A.

    1982-01-01

    The differences between powder and ingot metallurgy processing of aluminum alloys are outlined. The potential payoff in the use of advanced powder metallurgy (PM) aluminum alloys in future transport aircraft is indicated. The national program to bring this technology to commercial fruition and the NASA Langley Research Center role in this program are briefly outlined. Some initial results of research in 2000-series PM alloys and composites that highlight the property improvements possible are given.

  8. Fast LIBS Identification of Aluminum Alloys

    Directory of Open Access Journals (Sweden)

    Tawfik W.

    2007-04-01

    Full Text Available Laser-induced breakdown spectroscopy (LIBS has been applied to analysis aluminum alloy targets. The plasma is generated by focusing a 300 mJ pulsed Nd: YAG laser on the target in air at atmospheric pressure. Such plasma emission spectrum was collected using a one-meter length wide band fused-silica optical fiber connected to a portable Echelle spectrometer with intensified CCD camera. Spectroscopic analysis of plasma evolution of laser produced plasmas has been characterized in terms of their spectra, electron density and electron temperature assuming the LTE and optically thin plasma conditions. The LIBS spectrum was optimized for high S/N ratio especially for trace elements. The electron temperature and density were determined using the emission intensity and stark broadening, respectively, of selected aluminum spectral lines. The values of these parameters were found to change with the aluminum alloy matrix, i.e. they could be used as a fingerprint character to distinguish between different aluminum alloy matrices using only one major element (aluminum without needing to analysis the rest of elements in the matrix. Moreover, It was found that the values of T(e and N(e decrease with increasing the trace elements concentrations in the aluminum alloy samples. The obtained results indicate that it is possible to improve the exploitation of LIBS in the remote on-line industrial monitoring application, by following up only the values of T(e and N(e for the aluminum in aluminum alloys using an optical fiber probe.

  9. Fast LIBS Identification of Aluminum Alloys

    Directory of Open Access Journals (Sweden)

    Tawfik W.

    2007-04-01

    Full Text Available Laser-induced breakdown spectroscopy (LIBS has been applied to analysis aluminum alloy targets. The plasma is generated by focusing a 300 mJ pulsed Nd: YAG laser on the target in air at atmospheric pressure. Such plasma emission spectrum was collected using a one-meter length wide band fused-silica optical fiber connected to a portable Echelle spectrometer with intensified CCD camera. Spectroscopic analysis of plasma evolution of laser produced plasmas has been characterized in terms of their spectra, electron density and electron temperature assuming the LTE and optically thin plasma conditions. The LIBS spectrum was optimized for high S/N ratio especially for trace elements. The electron temperature and density were determined using the emission intensity and stark broadening, respectively, of selected aluminum spectral lines. The values of these parameters were found to change with the aluminum alloy matrix, i.e. they could be used as a fingerprint character to distinguish between different aluminum alloy matrices using only one major element (aluminum without needing to analysis the rest of elements in the matrix. Moreover, It was found that the values of T e and N e decrease with increasing the trace elements concentrations in the aluminum alloy samples. The obtained results indicate that it is possible to improve the exploitation of LIBS in the remote on-line industrial monitoring application, by following up only the values of T e and N e for aluminum in aluminum alloys as a marker for the correct alloying using an optical fiber probe.

  10. Transfer and transport of aluminum in filtration unit

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Aluminum salt coagulants were used prevalently in various water works. In this article, the effects of filtration on residual aluminum concentration and species distribution were researched by determining the concentration of different Aluminum species before and after single layer filter, double layer filter, and membrane filtration units. In the research, size exclusion chromatography (SEC) was used to separate colloidal and soluble aluminum, ion exchange chromatography (IEC) was used to separate organic and inorganic aluminum, and inductivity coupled plasma-atomic emission spectrometry (ICP-AES) was used to determine the aluminum concentration. The results showed that the rapid filtration process had the ability of removing residual aluminum from coagulant effluent water, and that double layer filtration was more effective in residual aluminum removal than single layer filtration, while Nano filtration was more effective than micro filtration. It was found that when the residual aluminum concentration was below 1mg/L in sediment effluent, the residual aluminum concentration in treated water was above 0.2 mg/L. The direct rapid filtration process mainly removed the suspended aluminum. The removal of soluble and colloidal aluminum was always less than 10% and the natural small particles that adsorbed the amount of soluble or small particles aluminum on their surface were difficult to be removed in this process. Micro filtration and nano filtration were good technologies for removing aluminum; the residual aluminum concentration in the effluent was less than 0.05 mg/L.

  11. Visible to near-infrared supercontinuum generation in yttrium orthosilicate bulk crystal and ion implanted planar waveguide

    Science.gov (United States)

    Xiang, Bingxi; Ren, Xikui; Ruan, Shuangchen; Wang, Lei; Yan, Peiguang; Han, Huangpu; Wang, Meng; Yin, Jinde

    2016-08-01

    This paper reports on the supercontinuum generation in yttrium orthosilicate bulk crystal and 6-mm-long ion implanted planar waveguide. The waveguide is fabricated by 6 MeV oxygen ions implantation with fluence of 5 × 1014 ions/cm2 at room temperature. The yttrium orthosilicate bulk crystal and waveguide are pumped using a mode-locked Ti:Sapphire laser with a center wavelength of 800 nm. The generated broadest supercontinuum spans 720 nm (at ‑30 dB points) from 380 to 1100 nm in bulk crystal and 510 nm (at ‑30 dB points) from 490 to 1000 nm in ion implanted waveguide, respectively. Compared to the bulk crystal, the ion implanted waveguide requires almost three orders of magnitude lower pump power to achieve a similar level of broadening. The supercontinuum is generated in the normal dispersion regime and exhibits a relatively smooth spectral shape. Our research findings indicate that ion implantation is an efficient method to produce waveguide in yttrium orthosilicate crystal for low-threshold supercontinuum generation.

  12. Influence of Yttrium Ion-Implantation on the Growth Kinetics and Micro-Structure of NiO Oxide Film

    Institute of Scientific and Technical Information of China (English)

    JIN Huiming; Adriana FELIX; Majorri AROYAVE

    2008-01-01

    Isothermal and cyclic oxidation behaviours of pure and yttrium-implanted nickel were studied at 1000℃ in air. Scanning electronic microscopy (SEM) and transmission electronic microscopy (TEM) were used to examine the micro-morphology and structure of oxide scales formed on the nickel substrate. It was found that Y-implantation significantly improved the anti-oxidation ability of nickel in both isothermal and cyclic oxidizing experiments. Laser Raman microscopy was also used to study the stress status of oxide scales formed on nickel with and without yttrium. The main reason for the improvement in anti-oxidation of nickel was that Y-implantation greatly reduced the growing speed and grain size of NiO. This fine-grained NiO oxide film might have better high temperature plasticity and could relieve parts of compressive stress by means of creeping, and maintained a ridge character and a relatively low internal stress level. Hence yttrium ion-implantation remarkably enhanced the adhesion of protective NiO oxide scale formed on the nickel substrate.

  13. Visible to near-infrared supercontinuum generation in yttrium orthosilicate bulk crystal and ion implanted planar waveguide.

    Science.gov (United States)

    Xiang, Bingxi; Ren, Xikui; Ruan, Shuangchen; Wang, Lei; Yan, Peiguang; Han, Huangpu; Wang, Meng; Yin, Jinde

    2016-08-16

    This paper reports on the supercontinuum generation in yttrium orthosilicate bulk crystal and 6-mm-long ion implanted planar waveguide. The waveguide is fabricated by 6 MeV oxygen ions implantation with fluence of 5 × 10(14) ions/cm(2) at room temperature. The yttrium orthosilicate bulk crystal and waveguide are pumped using a mode-locked Ti:Sapphire laser with a center wavelength of 800 nm. The generated broadest supercontinuum spans 720 nm (at -30 dB points) from 380 to 1100 nm in bulk crystal and 510 nm (at -30 dB points) from 490 to 1000 nm in ion implanted waveguide, respectively. Compared to the bulk crystal, the ion implanted waveguide requires almost three orders of magnitude lower pump power to achieve a similar level of broadening. The supercontinuum is generated in the normal dispersion regime and exhibits a relatively smooth spectral shape. Our research findings indicate that ion implantation is an efficient method to produce waveguide in yttrium orthosilicate crystal for low-threshold supercontinuum generation.

  14. Studies of aluminum in rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Lipman, J.J.; Brill, A.B.; Som, P.; Jones, K.W.; Colowick, S.; Cholewa, M.

    1985-01-01

    The effects of high aluminum concentrations in rat brains were studied using /sup 14/C autoradiography to measure the uptake of /sup 14/C 2-deoxy-D-glucose (/sup 14/C-2DG) and microbeam proton-induced x-ray emission (microPIXE) with a 20-..mu..m resolution to measure concentrations of magnesium, aluminum, potassium, and calcium. The aluminum was introduced intracisternally in the form of aluminum tartrate (Al-T) while control animals were given sodium tartrate (Na-T). The /sup 14/C was administered intravenously. The animals receiving Al-T developed seizure disorders and had pathological changes that included cerebral cortical atrophy. The results showed that there was a decreased uptake of /sup 14/C-2DG in cortical regions in which increased aluminum levels were measured, i.e., there is a correlation between the aluminum in the rat brain and decreased brain glucose metabolism. A minimum detection limit of about 16 ppM (mass fraction) or 3 x 10/sup 9/ Al atoms was obtained for Al under the conditions employed. 14 refs., 4 figs., 1 tab.

  15. Nanostructures Using Anodic Aluminum Oxide

    Science.gov (United States)

    Valmianski, Ilya; Monton, Carlos M.; Pereiro, Juan; Basaran, Ali C.; Schuller, Ivan K.

    2013-03-01

    We present two fabrication methods for asymmetric mesoscopic dot arrays over macroscopic areas using anodic aluminum oxide templates. In the first approach, metal is deposited at 45o to the template axis to partially close the pores and produce an elliptical shadow-mask. In the second approach, now underway, nanoimprint lithography on a polymer intermediary layer is followed by reactive ion etching to generate asymmetric pore seeds. Both these techniques are quantified by an analysis of the lateral morphology and lattice of the pores or dots using scanning electron microscopy and a newly developed MATLAB based code (available for free download at http://ischuller.ucsd.edu). The code automatically provides a segmentation of the measured area and the statistics of morphological properties such as area, diameter, and eccentricity, as well as the lattice properties such as number of nearest neighbors, and unbiased angular and radial two point correlation functions. Furthermore, novel user defined statistics can be easily obtained. We will additionally present several applications of these methods to superconducting, ferromagnetic, and organic nanostructures. This work is supported by AFOSR FA9550-10-1-0409

  16. Yttrium-90 resin microspheres as an adjunct to sorafenib in patients with unresectable hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Mahvash A

    2016-02-01

    Full Text Available Armeen Mahvash,1 Ravi Murthy,1 Bruno C Odisio,1 Kanwal Pratap Raghav,2 Lauren Girard,2 Sheree Cheung,1 Van Nguyen,3 Joe Ensor,4 Sameer Gadani,5 Khaled M Elsayes,6 Reham Abdel-Wahab,1,7 Manal Hassan,1 Ahmed S Shalaby,1 James C Yao,1 Michael J Wallace,1 Ahmed O Kaseb2 1Department of Interventional Radiology, 2Department of Gastrointestinal Medical Oncology, 3Department of Pharmacy, 4Department of Statistics, The University of Texas MD Anderson Cancer Center, Houston, TX, 5Department of Radiology, Saint Louis University Hospital, St Louis, MO, 6Department of Diagnostic Radiology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; 7Department of Clinical Oncology, Assiut University Hospital, Assiut, Egypt Purpose: The safety and efficacy of the combined use of sorafenib and yttrium-90 resin microspheres (Y90 RMS to treat advanced hepatocellular carcinoma (HCC is not well established. We determined the incidence of adverse events with this combination therapy in patients with advanced HCC at our institution and analyzed the treatment and survival outcomes. Materials and methods: We reviewed the records of 19 patients with Barcelona Clinic Liver Cancer class B or C HCC who underwent treatment with Y90 RMS (for 21 sessions while receiving full or reduced doses of sorafenib between January 2008 and May 2010. Therapy response was evaluated using Response Evaluation Criteria in Solid Tumors. We evaluated median overall survival (OS and progression-free survival (PFS as well as hepatic and extrahepatic disease PFS and incidence of adverse events. Results: The median patient age was 67 years, and portal or hepatic venous invasion was present in eight patients (42%. Ten patients received reduced doses of sorafenib. The median Y90 radiation activity delivered was 41.2 mCi. The partial response of Response Evaluation Criteria in Solid Tumors was observed in four patients (19%. The median hepatic disease PFS was 7.82 months, extrahepatic

  17. Combustion Synthesis of Yttrium BARIUM(2) COPPER(3) OXYGEN(6+X) Superconductor.

    Science.gov (United States)

    Lin, Sy-Chyi

    YBa_2Cu_3 O_{rm 6 + x} was produced from copper, barium peroxide, and yttrium oxide by Self-propagating High-temperature Synthesis (SHS) and thermal explosion methods. The SHS process was conducted in two modes: a horizontal combustion and a vertical combustion. The influence of copper particle size on the stability of the reaction front was studied. In contrast to previous studies, a stable reaction front could be maintained even when relatively large copper particles (smaller than 325 mesh) were used. In the horizontal SHS process, large diameter pellets (larger than 22 mm in diameter) enabled stable combustion at room temperature. Elevated ambient temperatures (400 {~} 500^circ C) were needed to stabilize the combustion front movement in small diameter pellets. The product had an average concentration of 84 wt% YBa_2Cu _3O_{rm 6 + x}. In the vertical SHS process, with the aid of a booster, the combustion front moved more rapidly and smoothly than that in the horizontal SHS process and gave a product concentration of about 90 wt% YBa _2Cu_3O_ {rm 6 + x}. High quality product (above 95 wt% YBa_2Cu_3 O_{rm 6 + x}) may be obtained by sintering/calcining the SHS product in an oxygen atmosphere. Three different sintering/calcining processes were studied and the required temperature and the time for each process were determined. The temperature at the center of the pellet in a vertical SHS was measured by thermocouples. The pellet temperature rise is a two step process. The first temperature rise is caused by the oxidation of the copper and the second is caused by the reaction between yttrium oxide and barium cuprate. A reaction mechanism is proposed to explain this behavior. A thermal explosion process was conducted in a continuous rotary kiln. In this mode a pellet was introduced suddenly into a heated rotary kiln causing it to be combusted. After the combustion, the pellet was sintered at 900 to 980 ^circC and a product containing about 95 wt% YBa_2Cu_3 O_{rm 6 + x

  18. Cytotoxicity and genotoxicity caused by yttrium oxide nanoparticles in HEK293 cells

    Directory of Open Access Journals (Sweden)

    Selvaraj V

    2014-03-01

    Full Text Available Vellaisamy Selvaraj,1 Sravanthi Bodapati,1 Elizabeth Murray,2 Kevin M Rice,1 Nicole Winston,1,3 Tolou Shokuhfar,4 Yu Zhao,4 Eric Blough1,3,5 1Center for Diagnostic Nanosystems, 2Department of Integrated Science and Technology, 3Department of Pharmaceutical Sciences and Research, School of Pharmacy, Marshall University, Huntington, WV, USA; 4Department of Mechanical Engineering and Engineering Mechanics, Michigan Technological University, Houghton, MI, USA; 5Department of Pharmacology, Physiology and Toxicology, School of Medicine, Marshall University, Huntington, WV, USA Background: The increased use of engineered nanoparticles (NPs has caused new concerns about the potential exposure to biological systems and the potential risk that these materials may pose on human health. Here, we examined the effects of exposure to different concentrations (0–50 µg/mL and incubation times (10 hours, 24 hours, or 48 hours of yttrium oxide (Y2O3 NPs on human embryonic kidney (HEK293 cells. Changes in cellular morphology, cell viability, cell membrane integrity, reactive oxygen species levels, mitochondrial membrane potential, cell death (apoptosis and necrosis, and the DNA damage after NP exposure were compared to the effects seen following incubation with paraquat, a known toxicant. Results: The 24-hour inhibitory concentration 50 (IC50 of Y2O3 NPs (41±5 nm in size in the HEK293 cells was found to be 108 µg/mL. Incubation with Y2O3 NPs (12.25–50 µg/mL increased the ratio of Bax/Bcl-2, caspase-3 expression and promoted apoptotic- and necrotic-mediated cell death in both a concentration and a time-dependent manner. Decreases in cell survivability were associated with elevations in cellular reactive oxygen species levels, increased mitochondrial membrane permeability, and evidence of DNA damage, which were consistent with the possibility that mitochondria impairment may play an important role in the cytotoxic response. Conclusion: These data demonstrate

  19. Anodized aluminum on LDEF: A current status of measurements on chromic acid anodized aluminum

    Science.gov (United States)

    Golden, Johnny L.

    1992-01-01

    Chromic acid anodize was used as the exterior coating for aluminum surfaces on LDEF to provide passive thermal control. Chromic acid anodized aluminum was also used as test specimens in thermal control coatings experiments. The following is a compilation and analysis of the data obtained thus far.

  20. Deposition of aluminum-magnesium alloys from electrolytes containing organo-aluminum complexes

    Energy Technology Data Exchange (ETDEWEB)

    Lehmkuhl, H.; Mehler, K.; Bongard, H.; Tesche, B. [Max-Planck-Inst. fuer Kohlenforschung, Muelheim an der Ruhr (Germany); Reinhold, B. [Audi AG Technische Entwicklung, Ingolstadt (Germany)

    2001-06-01

    Organo-aluminum compounds have been used for many years as electrolytes in the coating industry. In this communication the development of a galvanic process for generating aluminum-magnesium coatings from organometallic electrolyte systems is reported as well as results on physical properties like adhesion, ductility and corrosion resistance. (orig.)

  1. Polarization properties of real aluminum mirrors; I. Influence of the aluminum oxide layer

    CERN Document Server

    van Harten, G; Keller, C U

    2009-01-01

    In polarimetry it is important to characterize the polarization properties of the instrument itself to disentangle real astrophysical signals from instrumental effects. This article deals with the accurate measurement and modeling of the polarization properties of real aluminum mirrors, as used in astronomical telescopes. Main goals are the characterization of the aluminum oxide layer thickness at different times after evaporation and its influence on the polarization properties of the mirror. The full polarization properties of an aluminum mirror are measured with Mueller matrix ellipsometry at different incidence angles and wavelengths. The best fit of theoretical Mueller matrices to all measurements simultaneously is obtained by taking into account a model of bulk aluminum with a thin aluminum oxide film on top of it. Full Mueller matrix measurements of a mirror are obtained with an absolute accuracy of ~1% after calibration. The determined layer thicknesses indicate logarithmic growth in the first few hou...

  2. Progress in Aluminum Electrolysis Control and Future Direction for Smart Aluminum Electrolysis Plant

    Science.gov (United States)

    Zhang, Hongliang; Li, Tianshuang; Li, Jie; Yang, Shuai; Zou, Zhong

    2016-10-01

    The industrial aluminum reduction cell is an electrochemistry reactor that operates under high temperatures and highly corrosive conditions. However, these conditions have restricted the measurement of key control parameters, making the control of aluminum reduction cells a difficult problem in the industry. Because aluminum electrolysis control systems have a significant economic influence, substantial research has been conducted on control algorithms, control systems and information systems for aluminum reduction cells. This article first summarizes the development of control systems and then focuses on the progress made since 2000, including alumina concentration control, temperature control and electrolyte molecular ratio control, fault diagnosis, cell condition prediction and control system expansion. Based on these studies, the concept of a smart aluminum electrolysis plant is proposed. The frame construction, key problems and current progress are introduced. Finally, several future directions are discussed.

  3. Methods for both coating a substrate with aluminum oxide and infusing the substrate with elemental aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jung-Pyung; Weil, Kenneth Scott

    2016-11-01

    Methods of aluminizing the surface of a metal substrate. The methods of the present invention do not require establishment of a vacuum or a reducing atmosphere, as is typically necessary. Accordingly, aluminization can occur in the presence of oxygen, which greatly simplifies and reduces processing costs by allowing deposition of the aluminum coating to be performed, for example, in air. Embodiments of the present invention can be characterized by applying a slurry that includes a binder and powder granules containing aluminum to the metal substrate surface. Then, in a combined step, a portion of the aluminum is diffused into the substrate and a portion of the aluminum is oxidized by heating the slurry to a temperature greater than the melting point of the aluminum in an oxygen-containing atmosphere.

  4. Induced magnetism in exfoliated graphene via proximity effect with yttrium iron garnet thin films

    Science.gov (United States)

    Amado, Mario; Li, Yang; di Bernardo, Angelo; Lombardo, Antonio; Ferrari, Andrea C.; Robinson, Jason

    The recent discovery of the quantum anomalous Hall effect (QAHE) in magnetically doped topological insulators cooled below in the milikelvin regime represents breakthrough in the field of spintronics. Theoretically, the QAHE should occur in graphene proximity coupled to a ferromagnetic insulato but with the promise of much higher operating temperatures for practical applications. Hints of proximity-induced magnetism in graphene coupled to yttrium iron garnet (YIG) films have been reported although the QAHE remains unobserved; the lack of a fully developed plateau in graphene/YIG devices can be attributed to poor interfacial coupling and therefore a dramatically reduced magnetic proximity effect. Here we report the deposition and characterisation of epitaxial thin-films of YIG on lattice-matched gadolinium gallium garnet substrates by pulsed laser deposition. Pristine exfoliated graphene flakes transferred mechanically onto the YIG are reported alongside results that correlate the effects of YIG morphology on the electronic and crystal properties of graphene by electrical (low temperature magnetoresistance measurements in Hall-bar-like configuration) and optical (Raman) means.

  5. Investigation of high-k yttrium copper titanate thin films as alternative gate dielectrics

    Science.gov (United States)

    Grazia Monteduro, Anna; Ameer, Zoobia; Rizzato, Silvia; Martino, Maurizio; Caricato, Anna Paola; Tasco, Vittorianna; Chaitanya Lekshmi, Indira; Hazarika, Abhijit; Choudhury, Debraj; Sarma, D. D.; Maruccio, Giuseppe

    2016-10-01

    Nearly amorphous high-k yttrium copper titanate thin films deposited by laser ablation were investigated in both metal-oxide-semiconductor (MOS) and metal-insulator-metal (MIM) junctions in order to assess the potentialities of this material as a gate oxide. The trend of dielectric parameters with film deposition shows a wide tunability for the dielectric constant and AC conductivity, with a remarkably high dielectric constant value of up to 95 for the thick films and conductivity as low as 6  ×  10-10 S cm-1 for the thin films deposited at high oxygen pressure. The AC conductivity analysis points out a decrease in the conductivity, indicating the formation of a blocking interface layer, probably due to partial oxidation of the thin films during cool-down in an oxygen atmosphere. Topography and surface potential characterizations highlight differences in the thin film microstructure as a function of the deposition conditions; these differences seem to affect their electrical properties.

  6. Spatial evolution of multipeaked microwave magnetic envelope solitons in yttrium iron garnet thin films

    Science.gov (United States)

    Wu, Mingzhong; Kraemer, Michael A.; Scott, Mark M.; Patton, Carl E.; Kalinikos, Boris A.

    2004-08-01

    The spatial evolution of multi-peaked microwave magnetic envelope solitons in a thin yttrium iron garnet (YIG) film has been measured and analyzed. The experiments were done on a long and narrow 5-μm -thick single-crystal YIG film strip. Double-peaked and triple-peaked magnetostatic backward volume wave soliton pulses were excited at a nominal carrier frequency of 7.0GHz . The measurements utilized a movable inductive magnetodynamic probe detection system. The formation of these multi-peaked soliton (MPS) pulses is a two step process. First, an initial single large amplitude pulse gradually separates into two or more nonsolitonic peaks. After a certain propagation time, these nonsolitonic peaks evolve, in sequence, into solitonic peaks with constant phase (CP) and an overall stair-like profile. Typically, the larger amplitude peaks lead in time and become solitonic first. As the MPS signals propagate and decay, the peaks lose their CP character in reverse sequence. The region of existence for the “fully formed” MPS pulses for which all the individual peaks have CP character is extremely narrow, typically on the order of a few tenths of a millimeter. The velocities of the individual peaks scale linearly with the peak powers. A nonlinear response analysis of the peak velocity based on the method of envelopes gives a reasonable match to the data.

  7. Yttrium recovery from primary and secondary sources: a review of main hydrometallurgical processes.

    Science.gov (United States)

    Innocenzi, Valentina; De Michelis, Ida; Kopacek, Bernd; Vegliò, Francesco

    2014-07-01

    Yttrium is important rare earths (REs) used in numerous fields, mainly in the phosphor powders for low-energy lighting. The uses of these elements, especially for high-tech products are increased in recent years and combined with the scarcity of the resources and the environmental impact of the technologies to extract them from ores make the recycling waste, that contain Y and other RE, a priority. The present review summarized the main hydrometallurgical technologies to extract Y from ores, contaminated solutions, WEEE and generic wastes. Before to discuss the works about the treatment of wastes, the processes to retrieval Y from ores are discussed, since the processes are similar and derived from those already developed for the extraction from primary sources. Particular attention was given to the recovery of Y from WEEE because the recycle of them is important not only for economical point of view, considering its value, but also for environmental impact that this could be generated if not properly disposal.

  8. Photocatalytic degradation of methyl orange by polyoxometalates supported on yttrium-doped TiO2

    Institute of Scientific and Technical Information of China (English)

    WANG Yajun; LU Kecheng; FENG Changgen

    2011-01-01

    A series of novel photocatalysts,H3PW12O40-Y-TiO2 nanocomposites with different H3PW12O40 loading levels (10%-40%) were prepared by impregnation method.And the Y-TiO2 support,doped with yttrium,was synthesized via sol-gel technique.The prepared catalysts were characterized by Fourier transform infrared spectroscopy (FT-IR),powder X-ray diffraction (XRD),nitrogen adsorption-desorption analysis and scanning electron microscopy (SEM).The processes allowed obtaining Keggin structure and crystallized anatase with large BET surface area as well as uniform distribution.The effects of H3PW12O40 loadings,catalyst dose,initial pH and concentration of dye solution on the degradation kinetics of methyl orange under UV light (λ≥365 nm) were discussed.Kinetics studies showed that the photocatalytic degradation of methyl orange fitted the apparent first-order reaction.Methyl orange was totally degraded in 21 min under optimum conditions:20% loading,0.03 g dose and pH 1.0.The catalyst was stable and easily to be separated from reaction system for recovery.

  9. Yttrium-90 Radioembolization for Colorectal Cancer Liver Metastases: A Single Institution Experience

    Directory of Open Access Journals (Sweden)

    Gary W. Nace

    2011-01-01

    Full Text Available Purpose. We sought to evaluate our experience using yttrium-90 (90Y resin microsphere hepatic radioembolization as salvage therapy for liver-dominant metastatic colorectal cancer (mCRC. Methods. A retrospective review of consecutive patients with unresectable mCRC who were treated with 90Y after failing first and second line systemic chemotherapy. Demographics, treatment dose, biochemical and radiographic response, toxicities, and survival were examined. Results. Fifty-one patients underwent 90Y treatments of which 69% were male. All patients had previously undergone extensive chemotherapy, 31% had undergone previous liver-directed therapy and 24% had a prior liver resection. Using RECIST criteria, either stable disease or a partial response was seen in 77% of patients. Overall median survival from the time of first 90Y treatment was 10.2 months (95% CI = 7.5–13.0. The absence of extrahepatic disease at the time of treatment with 90Y was associated with an improved survival, median survival of 17.0 months (95% CI = 6.4–27.6, compared to those with extrahepatic disease at the time of treatment with 90Y, 6.7 months (95% CI = 2.7–10.6 Conclusion: 90Y therapy is a safe locoregional therapy that provides an important therapeutic option to patients who have failed first and second line chemotherapy and have adequate liver function and performance status.

  10. Yttrium-90 radioembolization for the treatment of unresectable liver cancer: Results of a single center

    Directory of Open Access Journals (Sweden)

    Özhan Özgür

    2014-03-01

    Full Text Available Objective: To determine the effects of yttrium-90 (Y-90 resin microsphere radioembolization therapy on patients with unresectable liver cancer who do not benefit from chemotherapy. Methods: Fifty-five patients underwent radioembolization therapy included in the study whose had unresectable primary or metastatic liver cancer originating from the gastrointestinal tract. Three were excluded from the study after pre-evaluation angiography. Thirteen (23.6% of the remaining 52 patients had hepatocellular carcinoma and 39 (76.4% had metastatic liver cancer. Fifty-two patients underwent Y-90 radioembolization treatment. Each patient's response to the administered treatment was evaluated using the Response Evaluation Criteria in Solid Tumors (RECIST and the overall probability of survival was displayed graphically by the Kaplan-Meier method. Results: After Y-90 therapy, 47 patients were follow-up. While 57% of the patients responded to treatment as clinical benefit, the disease progressed in 43%. The median hepatic progression-free survival time of the patients was 3.4 months (95% confidence interval (ci:1.4-5.3 and the overall survival time was 11.3 months (95%, CI:8.7-14.03. Conclusion: This study emphasizes that Y-90 resin microsphere radioembolization treatment is effective in patients with unresectable liver cancer.

  11. Characterization of Erbium Substituted Yttrium Iron Garnet Films Prepared by Sol-Gel Method

    Directory of Open Access Journals (Sweden)

    Ramadan E. Shaiboub

    2014-01-01

    Full Text Available Yttrium iron garnet (YIG thin films substituted erbium ions (Er+3 Er0.4Y2.6Fe5O12 films were prepared by a sol-gel method at different temperatures which varied from 800 to 1000°C for 2 hours in air. Magnetic and microstructural properties of the films were characterized with X-ray diffraction (XRD, the field emission scanning electron microscopy (FESEM, and vibrating sample magnetometer (VSM. The XRD patterns of the sample have only peaks of the garnet structure. The lattice constants decrease, while the particle size increases from 51 to 85 nm as the annealing temperature increases with average in thickness of 300 nm. The saturation magnetization and the coercivity of the samples increased from 26 (emu/cc and 28 Oe for the film annealed at 800°C to 76 (emu/cc and 45 Oe for film annealed at 1000°C, respectively.

  12. Patient Selection and Activity Planning Guide for Selective Internal Radiotherapy With Yttrium-90 Resin Microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Lau, Wan-Yee, E-mail: josephlau@surgery.cuhk.edu.hk [Faculty of Medicine, Chinese University of Hong Kong, Shatin, New Territories (Hong Kong); Kennedy, Andrew S. [Wake Radiology Oncology, Cary, NC (United States); Department of Biomedical Engineering, North Carolina State University, Raleigh, NC (United States); Kim, Yun Hwan [Department of Radiology, Anam Hospital, Korea University College of Medicine, Seoul (Korea, Republic of); Lai, Hee Kit [Nuclear Medicine and PET Centre, Mount Elizabeth Hospital, Singapore (Singapore); Lee, Rheun-Chuan [Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan (China); Leung, Thomas W.T. [Comprehensive Oncology Centre, Hong Kong Sanatorium and Hospital (Hong Kong); Liu, Ching-Sheng [Department of Nuclear Medicine, Taipei Veterans General Hospital, Taipei, Taiwan (China); Salem, Riad [Division of Interventional Radiology, Northwestern University, Chicago, IL (United States); Sangro, Bruno [Liver Unit, Clinica Universitaria de Navarra and Centro de Investigacion Biomedica en Red de Enfermedades Hepaticas y Digestivas, Pamplona (Spain); Shuter, Borys [Department of Diagnostic Imaging, National University Hospital, Singapore (Singapore); Wang, Shih-Chang [Parker-Hughes Professor of Diagnostic Radiology, University of Sydney, Sydney, NSW (Australia)

    2012-01-01

    Purpose: Selective internal radiotherapy (SIRT) with yttrium-90 ({sup 90}Y) resin microspheres can improve the clinical outcomes for selected patients with inoperable liver cancer. This technique involves intra-arterial delivery of {beta}-emitting microspheres into hepatocellular carcinomas or liver metastases while sparing uninvolved structures. Its unique mode of action, including both {sup 90}Y brachytherapy and embolization of neoplastic microvasculature, necessitates activity planning methods specific to SIRT. Methods and Materials: A panel of clinicians experienced in {sup 90}Y resin microsphere SIRT was convened to integrate clinical experience with the published data to propose an activity planning pathway for radioembolization. Results: Accurate planning is essential to minimize potentially fatal sequelae such as radiation-induced liver disease while delivering tumoricidal {sup 90}Y activity. Planning methods have included empiric dosing according to degree of tumor involvement, empiric dosing adjusted for the body surface area, and partition model calculations using Medical Internal Radiation Dose principles. It has been recommended that at least two of these methods be compared when calculating the microsphere activity for each patient. Conclusions: Many factors inform {sup 90}Y resin microsphere SIRT activity planning, including the therapeutic intent, tissue and vasculature imaging, tumor and uninvolved liver characteristics, previous therapies, and localization of the microsphere infusion. The influence of each of these factors has been discussed.

  13. Yttrium-90 microsphere radioembolization for the treatment of liver malignancies: a structured meta-analysis

    Energy Technology Data Exchange (ETDEWEB)

    Vente, M.A.D.; Wondergem, M.; Bosch, M.A.A.J. van den; Lam, M.G.E.H.; Schip, A.D. van het; Nijsen, J.F.W. [University Medical Center Utrecht, Department of Radiology and Nuclear Medicine, Utrecht (Netherlands); Tweel, I. van der [Utrecht University, Centre for Biostatistics, Utrecht (Netherlands); Zonnenberg, B.A. [University Medical Center Utrecht, Department of Internal Medicine, Utrecht (Netherlands)

    2009-04-15

    Radioembolization with yttrium-90 microspheres ({sup 90}Y-RE), either glass- or resin-based, is increasingly applied in patients with unresectable liver malignancies. Clinical results are promising but overall response and survival are not yet known. Therefore a meta-analysis on tumor response and survival in patients who underwent {sup 90}Y-RE was conducted. Based on an extensive literature search, six groups were formed. Determinants were cancer type, microsphere type, chemotherapy protocol used, and stage (deployment in first-line or as salvage therapy). For colorectal liver metastases (mCRC), in a salvage setting, response was 79% for {sup 90}Y-RE combined with 5-fluorouracil/leucovorin (5-FU/LV), and 79% when combined with 5-FU/LV/oxaliplatin or 5-FU/LV/irinotecan, and in a first-line setting 91% and 91%, respectively. For hepatocellular carcinoma (HCC), response was 89% for resin microspheres and 78% for glass microspheres. No statistical method is available to assess median survival based on data presented in the literature. In mCRC, {sup 90}Y-RE delivers high response rates, especially if used neoadjuvant to chemotherapy. In HCC, {sup 90}Y-RE with resin microspheres is significantly more effective than {sup 90}Y-RE with glass microspheres. The impact on survival will become known only when the results of phase III studies are published. (orig.)

  14. Marine Phosphorites as Potential Resources for Heavy Rare Earth Elements and Yttrium

    Directory of Open Access Journals (Sweden)

    James R. Hein

    2016-08-01

    Full Text Available Marine phosphorites are known to concentrate rare earth elements and yttrium (REY during early diagenetic formation. Much of the REY data available are decades old and incomplete, and there has not been a systematic study of REY distributions in marine phosphorite deposits that formed over a range of oceanic environments. Consequently, we initiated this study to determine if marine phosphorite deposits found in the global ocean host REY concentrations of high enough grade to be of economic interest. This paper addresses continental-margin (CM and open-ocean seamount phosphorites. All 75 samples analyzed are composed predominantly of carbonate fluorapatite and minor detrital and authigenic minerals. CM phosphorites have low total REY contents (mean 161 ppm and high heavy REY (HREY complements (mean 49%, while seamount phosphorites have 4–6 times higher individual REY contents (except for Ce, which is subequal; mean ΣREY 727 ppm, and very high HREY complements (mean 60%. The predominant causes of higher concentrations and larger HREY complements in seamount phosphorites compared to CM phosphorites are age, changes in seawater REY concentrations over time, water depth of formation, changes in pH and complexing ligands, and differences in organic carbon content in the depositional environments. Potential ore deposits with high HREY complements, like the marine phosphorites analyzed here, could help supply the HREY needed for high-tech and green-tech applications without creating an oversupply of the LREY.

  15. Synthesis and characterization of pyrochlore-type yttrium titanate nanoparticles by modified sol–gel method

    Indian Academy of Sciences (India)

    Z S Chen; W P Gong; T F Chen; S L Li

    2011-06-01

    Pyrochlore-type yttrium titanate (Y2Ti2O7) nanoparticles were successfully synthesized by a simple soft-chemistry technique viz. citric acid sol–gel method (CAM). The preparation process was monitored by X-ray diffraction, thermogravimetric–differential thermal analysis and Fourier transform–infrared experiments and the microstructures and average size of as-prepared products were characterized by transmission electron microscopy and high resolution transmission electron microscopy images. It was found that compared with traditional solid state reaction (SSR), Y2Ti2O7 nanopowders were synthesized at a relatively low temperature (750°C) for shortened reaction time. Detailed analysis showed that the as-prepared Y2Ti2O7 with good dispersibility and narrow size distribution were quasi-spherical; the average size was about 20–30 nm, also, the obtained products had higher BET surface area (50 m2/g). These properties are very helpful for a photocatalyst to achieve excellent activity and may result in better behaviour in hydrogen storage.

  16. Structural and spectroscopic analyses of europium doped yttrium oxyfluoride powders prepared by combustion synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Rakov, Nikifor [PG-Ciência dos Materiais, Universidade Federal do Vale do São Francisco, 48902-300 Juazeiro, BA (Brazil); Guimarães, R. B.; Maciel, Glauco S. [Instituto de Física, Universidade Federal Fluminense, 24210-346 Niterói, RJ (Brazil); Lozano B, W. [Departamento de Física, Universidade Federal de Pernambuco, 50670-901 Recife, PE (Brazil)

    2013-07-28

    A facile widely spread technique employed to produce low-cost high-yield oxide powders, combustion synthesis, was used to prepare yttrium oxyfluoride crystalline ceramic powders. The structure of the powders was analyzed by X-ray powder diffraction and Rietveld refinement. Samples heat treated at 700 °C had a predominance of vernier orthorhombic Y{sub 6}O{sub 5}F{sub 8} phase, while samples heat treated at 800 °C crystallized in stoichiometric rhombohedral YOF phase. The samples were doped with luminescent europium trivalent ions (Eu{sup 3+}) in different concentrations (1–15 wt.%) and Judd-Ofelt theory was used to probe the distortion from the inversion symmetry of the local crystal field and the degree of covalency between the rare-earth ion and the surrounding ligands. The luminescence lifetime was measured and the luminescence quantum efficiency (LQE) was estimated. We observed that Eu{sup 3+}:Y{sub 6}O{sub 5}F{sub 8} samples presented higher LQE in spite of the larger local crystal field anisotropy found for Eu{sup 3+}:YOF samples.

  17. Prediction of yttrium, lanthanum, cerium, and neodymium leaching recovery from apatite concentrate using artificial neural networks

    Institute of Scientific and Technical Information of China (English)

    E. Jorjani; A.H. Bagherieh; Sh. Mesroghli; S. Chehreh Chelgani

    2008-01-01

    The assay and recovery of rare earth elements (REEs) in the leaching process is being determined using expensive analytical methods: inductively coupled plasma atomic emission spectroscopy (ICP-AES) and inductively coupled plasma mass spectroscopy (ICP-MS). A neural network model to predict the effects of operational variables on the lanthanum, cerium, yttrium, and neodymium recovery in the leaching of apatite concentrate is presented in this article. The effects of leaching time (10 to 40 min),pulp densities (30% to 50%), acid concentrations (20% to 60%), and agitation rates (100 to 200 r/min), were investigated and optimized on the recovery of REEs in the laboratory at a leaching temperature of 60οC. The obtained data in the laboratory optimization process were used for training and testing the neural network. The feed-forward artificial neural network with a 4-5-5-1 arrangement was capable of estimating the leaching recovery of REEs. The neural network predicted values were in good agreement with the experimental results. The correlations of R=1 in training stages, and R=0.971, 0.952, 0.985, and 0.98 in testing stages were a result of Ce, Nd, La, and Y recovery prediction respectively, and these values were usually acceptable. It was shown that the proposed neural network model accurately reproduced all the effects of the operation variables, and could be used in the simulation of a leaching plant for REEs.

  18. Synthesis of nanocrystalline yttrium iron garnet by low temperature solid state reaction

    Energy Technology Data Exchange (ETDEWEB)

    Yu Hongtao, E-mail: yuhongtao@swust.edu.cn; Zeng Liwen; Lu Chao; Zhang Wenbo; Xu Guangliang

    2011-04-15

    In this work, nanocrystalline yttrium iron garnet powders were produced by low temperature solid state reaction. The phase evolution during the procedure was determined from the thermogravimetric and differential thermal analysis, and the x-ray diffraction patterns. The results of transmission electron microscopy indicated that the prepared powders exhibited grain size at the nano-level of 20 {approx} 40 nm. Dense ceramics with a theoretical density of around 98% were obtained from the prepared powders after sintering at 1280 deg. C, a relative low sintering temperature compared with conventional ceramic processes, and the saturation magnetizations of sintered samples were also determined. - Research Highlights: {yields}No sol or gel form during the synthesis processing using nitrates and citric acid as raw materials. {yields}The synthesis method needs a low heating temperature (700 deg. C) compared with conventional solid state reaction. {yields}The product is a single phase with homogeneous size distribution and nano grains (20 {approx} 40 nm) confirmed by TEM. {yields}Dense YIG ceramic can be sintered at a low temperature (1280 deg. C) compared with that in conventional processing.

  19. Effective fingerprint recognition technique using doped yttrium aluminate nano phosphor material.

    Science.gov (United States)

    Darshan, G P; Premkumar, H B; Nagabhushana, H; Sharma, S C; Prashanth, S C; Prasad, B Daruka

    2016-02-15

    First time the yttrium aluminate nanoparticles are used to improve the fingerprint quality. Eco-friendly green combustion process is used to synthesize YAlO3:Sm(3+) (0.5-11mol%) nanophosphor using green tea leaf extract as non-toxic and eco-friendly fuel. Powder X-ray diffraction study confirms the orthorhombic phase. The average sizes of the crystallites were found to be in the range 20-35nm. The emission peaks centered at 564, 601 and 647nm is attributed to 4f-4f (4)G5/2→(6)HJ=5/2,7/2,9/2 forbidden transitions of Sm(3+) ions. Judd-Ofelt theory is applied to experimental data for providing qualitative support by determining J-O intensity parameters. The Commission International De I-Eclairage chromaticity co-ordinates are very close to National Television System Committee standard value of white emission (x=0.296, y=0.237). Further, correlated color temperature is found to be ∼11,900K. A simple, fast, highly sensitive and low-cost method for the detection and enhancement of fingermarks in a broad range of surfaces is developed and constitutes an alternative to traditional luminescent powders.

  20. X-ray analysis of the actual structure of yttrium orthoborate YBO3

    Science.gov (United States)

    Shmyt'ko, I. M.; Ganeeva, G. R.

    2016-12-01

    Detailed X-ray analysis of variations in the structure of yttrium orthoborate in the process of successive high-temperature isothermal anneals of an originally amorphous precursor state is performed. It is established that the diffraction reflex intensity distribution of YBO3 measured at room temperature, obtained in the initial stages of crystallization, corresponds to the known low-temperature vaterite phase with the space group (sp. gr.) P63/ m and, after a series of high-temperature anneals, it transforms into a distribution known for the vaterite modification with the sp. gr. P63/ mmc and the same lattice parameters. This result is explained on the basis of the sphericity of X-ray waves and is connected with the transformation of the crystallites from a spherical shape upon low-temperature anneals to a dumbbell shape upon high-temperature anneals. As a result of in situ experiments conducted at 1250°C, it was established that the initial low-temperature hexagonal vaterite cell transforms above 1000°C into a monoclinic cell.

  1. Research on cathode material of Li-ion battery by yttrium doping

    Institute of Scientific and Technical Information of China (English)

    TIAN Yanwen; KANG Xiaoxue; LIU Liying; XU Chaqing; QU Tao

    2008-01-01

    Modification of LiFePO4, LiMn2O4 and Li1+xV3O8 by doping yttrium was investigated. The influences of doping Y on structure, morphology and electrochemical performance of cathode materials were investigated systematically. The results indicated that the mechanisms of Y doping in three cathode materials were different, so the influences on the material performance were different. The crystal structure of the three materials was not changed by Y doping. However, the crystal parameters were influenced. The crystal parameters of LiMn2O4 became smaller, and the interlayer distance of (100) crystal plane of Li1+xV3O8 was lengthened after Y doping. The grain size of Y-doped LiFePO4 became smaller and grain morphology became more regular than that of undoped LiFePO4. It indicated that Y doping had no influence on crystal particle and morphology of LiMn2O4. The morphology of Li1+xV3O8 became irregular and its size became larger with the increase of Y. For LiFePO4 and Li1+xV3O8, both the initial discharge capacities and the cyclic performance were improved by Y doping. For LiMn2O4, the cyclic performance became better and the initial discharge capacities declined with increasing Y doping.

  2. Effect of mischmetal and yttrium on microstructures and mechanical properties of Mg-Al alloy

    Institute of Scientific and Technical Information of China (English)

    张诗昌; 魏伯康; 蔡启舟; 王立世

    2003-01-01

    The effect of yttrium and mischmetal(MMs) on the as-cast and solid solution treated structures of Mg-Al alloys with different Al-contents was investigated. The results show that the MMs in Mg-Al alloy existed in rodAl4 (Ce, La)compound while Y in Mg-Al alloy in polygonal Al2 Y compound. The amount of Mg17 Al12 in Mg-Al al-loy is decreased with increasing Y or MMs addition, and Mg17 Al12 intermetallic compound is changed from continu-ous network to discontinuous one. The Al4 (Ce, La) and Al2 Y compounds are not dissolved into Mg-Al alloy matrixduring solid solution treatment so that their high heat stability can be exhibited. The experiment of mechanical prop-erties indicate that elongation and impact toughness of the Mg-Al-Y alloy with polygonal Al2 Y compound are higherthan those of Mg-Al-MMs alloy with rod Al4 (Ce, La) compound.

  3. Structural and spectroscopic analyses of europium doped yttrium oxyfluoride powders prepared by combustion synthesis

    Science.gov (United States)

    Rakov, Nikifor; Guimarães, R. B.; Lozano B., W.; Maciel, Glauco S.

    2013-07-01

    A facile widely spread technique employed to produce low-cost high-yield oxide powders, combustion synthesis, was used to prepare yttrium oxyfluoride crystalline ceramic powders. The structure of the powders was analyzed by X-ray powder diffraction and Rietveld refinement. Samples heat treated at 700 °C had a predominance of vernier orthorhombic Y6O5F8 phase, while samples heat treated at 800 °C crystallized in stoichiometric rhombohedral YOF phase. The samples were doped with luminescent europium trivalent ions (Eu3+) in different concentrations (1-15 wt.%) and Judd-Ofelt theory was used to probe the distortion from the inversion symmetry of the local crystal field and the degree of covalency between the rare-earth ion and the surrounding ligands. The luminescence lifetime was measured and the luminescence quantum efficiency (LQE) was estimated. We observed that Eu3+:Y6O5F8 samples presented higher LQE in spite of the larger local crystal field anisotropy found for Eu3+:YOF samples.

  4. Toxicological effects of rare earth yttrium on wheat seedlings (Triticum aestivum)

    Institute of Scientific and Technical Information of China (English)

    冯秀娟; 朱国才; 李亚宁

    2013-01-01

    This study examined the biochemical responses of wheat (Triticum aestivum) to the stress of rare earth yttrium (Y) and showed that 25-100 mg/kg Y treatments evidently increased the biomass (root mass, shoot mass and leaf mass), accompanied by a significant (p<0.05) increase in the chlorophyll (CHL) content in wheat leaves. Increased malondialdehyde (MDA) levels were de-tected in wheat shoots (stem and leaf) and roots too, indicating the presence of poisoning active oxygen species (AOS). The MDA content in wheat roots increased with the augmentation of Y concentration. These results indicated that there was a dose-dependent effect of Y on the changes of MDA content in wheat roots. Although the activities of superoxide dismutases (SOD), peroxidases (POD) and catalases (CAT) in wheat shoots and roots irregularly fluctuated with the increase in Y concentration, 25-100 mg/kg Y significantly (p<0.01) increased the activities of SOD and POD. In general, the dose-dependent effects of Y on the activity of anti-oxidant enzymes were insignificant. Our data also indicated that the increase in SOD and POD activities could be used as a good bio-marker for the stress induced by low concentrations of Y.

  5. Marine phosphorites as potential resources for heavy rare earth elements and yttrium

    Science.gov (United States)

    Hein, James; Koschinsky, Andrea; Mikesell, Mariah; Mizell, Kira; Glenn, Craig R.; Wood, Ray

    2016-01-01

    Marine phosphorites are known to concentrate rare earth elements and yttrium (REY) during early diagenetic formation. Much of the REY data available are decades old and incomplete, and there has not been a systematic study of REY distributions in marine phosphorite deposits that formed over a range of oceanic environments. Consequently, we initiated this study to determine if marine phosphorite deposits found in the global ocean host REY concentrations of high enough grade to be of economic interest. This paper addresses continental-margin (CM) and open-ocean seamount phosphorites. All 75 samples analyzed are composed predominantly of carbonate fluorapatite and minor detrital and authigenic minerals. CM phosphorites have low total REY contents (mean 161 ppm) and high heavy REY (HREY) complements (mean 49%), while seamount phosphorites have 4–6 times higher individual REY contents (except for Ce, which is subequal; mean ΣREY 727 ppm), and very high HREY complements (mean 60%). The predominant causes of higher concentrations and larger HREY complements in seamount phosphorites compared to CM phosphorites are age, changes in seawater REY concentrations over time, water depth of formation, changes in pH and complexing ligands, and differences in organic carbon content in the depositional environments. Potential ore deposits with high HREY complements, like the marine phosphorites analyzed here, could help supply the HREY needed for high-tech and green-tech applications without creating an oversupply of the LREY.

  6. Non-local thermal spin injection to study spin diffusion in yttrium iron garnet

    Science.gov (United States)

    Giles, Brandon; Yang, Zihao; Jamison, John; Myers, Roberto

    Understanding the generation, detection, and manipulation of spin current is critical for the development of devices that depend on spin transport for information processing and storage. Recent studies have shown that spin transport over long distances is possible in the magnetic insulator yttrium iron garnet (YIG) through the diffusion of non-equilibrium magnons. Electrically excited magnons have been shown to diffuse up to 40um at room temperature, while thermally injected magnons were detected at ranges greater than 125um at 23K. However, much work is still required to fully understand the processes responsible for magnon diffusion. Here, we present an in-depth study of the diffusion of magnons in YIG. By using the non-local thermal spin detection method, we analyze spin transport as a function of temperature. Spin diffusion maps, which can be used to experimentally determine the spin diffusion length in YIG as a function of temperature, are presented Work supported by the Army Research Office MURI W911NF-14-1-0016.

  7. Precision mass measurements of neutron-rich yttrium and niobium isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Hager, U. [Department of Physics, University of Jyvaeskylae, PO Box 35 (YFL), FIN-40014 (Finland)], E-mail: ulrike.hager@phys.jyu.fi; Jokinen, A.; Elomaa, V.-V.; Eronen, T.; Hakala, J.; Kankainen, A.; Rahaman, S.; Rissanen, J.; Moore, I.D.; Rinta-Antila, S.; Saastamoinen, A.; Sonoda, T.; Aystoe, J. [Department of Physics, University of Jyvaeskylae, PO Box 35 (YFL), FIN-40014 (Finland)

    2007-09-01

    The atomic masses of neutron-rich {sup 95-101}Y and {sup 101-107}Nb produced in proton-induced fission of uranium were determined using the JYFLTRAP double Penning trap setup. Accuracies of better than 10 keV could be reached for most nuclides. The masses of {sup 106,107}Nb were measured for the first time. The energies of the isomeric states in {sup 96}Y and {sup 100}Y were measured as 1541(10) keV and 145(15) keV. The niobium isotopes appear to be systematically less bound than the values given in the latest Atomic Mass Evaluation. The new data lie in a region of the nuclear chart characterised by the transition from spherical to strongly deformed shapes. These structural changes are explored by studying different systematic trends. The data are also compared to several model predictions to test their ability to reproduce the structural changes along the isotopic chains of yttrium and niobium.

  8. Investigation of nanostructural, thermal and magnetic properties of yttrium iron garnet synthesized by mechanochemical method

    Energy Technology Data Exchange (ETDEWEB)

    Karami, M.A. [Materials Science and Engineering Department, School of Engineering, Shiraz University, Shiraz (Iran, Islamic Republic of); Shokrollahi, H., E-mail: shokrollahi@sutech.ac.ir [Electroceramics Group, Materials Science and Engineering Department, Shiraz University of Technology, 71555-313 Shiraz (Iran, Islamic Republic of); Hashemi, B. [Materials Science and Engineering Department, School of Engineering, Shiraz University, Shiraz (Iran, Islamic Republic of)

    2012-09-15

    This paper focuses on the magnetic, structural and thermal properties of mechanically alloyed Y{sub 2}O{sub 3}/{alpha}-Fe{sub 2}O{sub 3} mixed powders and investigates the effects of the mechanical milling and heat treatment on the synthesis of yttrium iron garnet from the primary materials. The morphological and structural studies were carried out by scanning electron microscope and X-ray diffraction, respectively. The thermal activities were measured by differential thermal analysis. The magnetic properties were studied by vibrating sample magnetometer. The results showed that high-energy milling does not lead to the garnet formation and even does not decrease the temperature of the garnet formation. Furthermore, the orthoferrite phase can be achieved slightly during the milling process (up to 96 h) and completely by the heat treatment at lower temperatures (850 Degree-Sign C). - Highlights: Black-Right-Pointing-Pointer The results showed that high energy milling did not lead to the garnet formation. Black-Right-Pointing-Pointer The milling process did not decrease the temperature of the garnet formation. Black-Right-Pointing-Pointer The orthoferrite phase can be achieved slightly during the mechanical milling. Black-Right-Pointing-Pointer The milling process can lower the temperature of orthoferrite formation. Black-Right-Pointing-Pointer The milled powder for 96 h completely transforms to orthoferrite below 700 Degree-Sign C.

  9. Fatigue mechanism of yttrium-doped hafnium oxide ferroelectric thin films fabricated by pulsed laser deposition.

    Science.gov (United States)

    Huang, Fei; Chen, Xing; Liang, Xiao; Qin, Jun; Zhang, Yan; Huang, Taixing; Wang, Zhuo; Peng, Bo; Zhou, Peiheng; Lu, Haipeng; Zhang, Li; Deng, Longjiang; Liu, Ming; Liu, Qi; Tian, He; Bi, Lei

    2017-02-01

    Owing to their prominent stability and CMOS compatibility, HfO2-based ferroelectric films have attracted great attention as promising candidates for ferroelectric random-access memory applications. A major reliability issue for HfO2 based ferroelectric devices is fatigue. So far, there have been a few studies on the fatigue mechanism of this material. Here, we report a systematic study of the fatigue mechanism of yttrium-doped hafnium oxide (HYO) ferroelectric thin films deposited by pulsed laser deposition. The influence of pulse width, pulse amplitude and temperature on the fatigue behavior of HYO during field cycling is studied. The temperature dependent conduction mechanism is characterized after different fatigue cycles. Domain wall pinning caused by carrier injection at shallow defect centers is found to be the major fatigue mechanism of this material. The fatigued device can fully recover to the fatigue-free state after being heated at 90 °C for 30 min, confirming the shallow trap characteristic of the domain wall pinning defects.

  10. Luminescence studies of rare earth doped yttrium gadolinium mixed oxide phosphor

    Energy Technology Data Exchange (ETDEWEB)

    Som, S.; Choubey, A. [Department of Applied Physics, Indian School of Mines, Dhanbad, Jharkhand 826004 (India); Sharma, S.K., E-mail: sksharma_ism@yahoo.co.in [Department of Applied Physics, Indian School of Mines, Dhanbad, Jharkhand 826004 (India)

    2012-09-01

    This paper reports the photoluminescence and thermoluminescence properties of gamma ray induced rare earth doped yttrium gadolinium mixed oxide phosphor. The europium (Eu{sup 3+}) was used as rare earth dopant. The phosphor was prepared by chemical co-precipitation method according to the formula (Y{sub 2-x-y}Gd{sub x}) O{sub 3}: Eu{sub y}{sup 3+} (x=0.5; y=0.05). The photoluminescence emission spectrum of the prepared phosphor shows intense peaks in the red region at 615 nm for {sup 5}D{sub 0}{yields}{sup 7}F{sub 2} transitions and the photoluminescence excitation spectra show a broad band located around 220-270 nm for the emission wavelength fixed at 615 nm. The thermoluminescence studies were carried out after irradiating the phosphor by gamma rays in the dose range from 100 Gy to 1 KGy. In the thermoluminescence glow curves, one single peak was observed at about 300 Degree-Sign C of which the intensity increases linearly in the studied dose range of gamma rays. The glow peak was deconvoluted by GlowFit program and the kinetic parameters associated with the deconvoluted peaks were calculated. The kinetic parameters were also calculated by various glow curve shape and heating rate methods.

  11. Luminescence studies of rare earth doped yttrium gadolinium mixed oxide phosphor

    Science.gov (United States)

    Som, S.; Choubey, A.; Sharma, S. K.

    2012-09-01

    This paper reports the photoluminescence and thermoluminescence properties of gamma ray induced rare earth doped yttrium gadolinium mixed oxide phosphor. The europium (Eu3+) was used as rare earth dopant. The phosphor was prepared by chemical co-precipitation method according to the formula (Y2-x-yGdx) O3: Euy3+ (x=0.5; y=0.05). The photoluminescence emission spectrum of the prepared phosphor shows intense peaks in the red region at 615 nm for 5D0→7F2 transitions and the photoluminescence excitation spectra show a broad band located around 220-270 nm for the emission wavelength fixed at 615 nm. The thermoluminescence studies were carried out after irradiating the phosphor by gamma rays in the dose range from 100 Gy to 1 KGy. In the thermoluminescence glow curves, one single peak was observed at about 300 °C of which the intensity increases linearly in the studied dose range of gamma rays. The glow peak was deconvoluted by GlowFit program and the kinetic parameters associated with the deconvoluted peaks were calculated. The kinetic parameters were also calculated by various glow curve shape and heating rate methods.

  12. Synthesis and optical characteristics of yttrium-doped zinc oxide nanorod arrays grown by hydrothermal method.

    Science.gov (United States)

    Park, Hyunggil; Kim, Younggyu; Ji, Iksoo; Lee, Sang-Heon; Kim, Jin Soo; Kim, Jin Soo; Leem, Jae-Young

    2014-11-01

    Yttrium-doped ZnO (YZO) nanorods were synthesized by hydrothermal growth on a quartz substrate with various post-annealing temperatures. To investigate the effects of post-annealing on the optical properties and parameters of the nanorods, X-ray diffractometry (XRD), photoluminescence (PL) measurement, and ultraviolet (UV)-visible spectroscopy were used. From the XRD investigation, the full width at half maximum (FWHM) and the dislocation density of the nanorods was found to increase with an increase in the post-annealing temperature. In the PL spectra, the intensity of the near band edge (NBE) emission peak in the UV region also increases with an increase in the temperature of post-annealing. The deep level emission (DLE) peak in the visible region changes with various post-annealing temperatures, and its intensity increases remarkably with post-annealing at 800 degrees C. In this paper, changes in the optical parameters of the nanorods caused by variation in the behavior of Y during post-annealing was investigated, with properties such as absorption coefficients, refractive indices, and dispersion parameters being obtained from transmittance and reflectance analysis.

  13. Giant Zeeman shifts in the optical transitions of yttrium iron garnet thin films

    Science.gov (United States)

    Vidyasagar, R.; Alves Santos, O.; Holanda, J.; Cunha, R. O.; Machado, F. L. A.; Ribeiro, P. R. T.; Rodrigues, A. R.; Mendes, J. B. S.; Azevedo, A.; Rezende, S. M.

    2016-09-01

    We report the observation of giant Zeeman shifts in the optical transitions of high-quality very thin films of yttrium iron garnet (YIG) grown by rf sputtering on gadolinium gallium garnet substrates. The optical absorption profile measured with magneto-optical absorption spectroscopy shows dual optical transition in the UV-visible frequency region attributed to transitions from the O-2p valence band to the Fe-3d conduction band and from the O-2p valence band to Fe-2p53d6 excitonic states at the Γ-symmetry point of the YIG band structure. The application of a static magnetic field of only 0.6 kOe produces giant Zeeman shifts of ˜100 meV in the YIG band structure and ˜60 meV in the excitonic states corresponding to effective g-factors on the order of 104. The giant Zeeman effects are attributed to changes in energy levels by the large exchange fields of the Fe-3d orbitals during the magnetization process.

  14. Thermally induced transparency for short spin wave pulses in yttrium iron garnet (YIG) films

    Science.gov (United States)

    Ordonez Romero, Cesar Leonardo; Kolokoltsev, Oleg; Gomez Arista, Ivan; Qureshi, Naser; Monsiváis Galindo, Guillermo; Vargas Hernández, Hesiquio

    2014-03-01

    The compensation of spin wave propagation losses plays a very important role in the development of novel magnonic devices. Up to now, however, most of the known amplification methods present relative narrow frequency bandwidths due to their resonant nature. In this work, we present compensation of the propagation losses or pseudo-amplification of travelling spin waves by tailoring the bias magnetic field profile. The thermally-induced non-uniform profile of the magnetization introduced on an Yttrium Iron Garnet (YIG) thin film by a localized spot of a cw argon-ion laser creates the conditions to observe the complete compensation of the spin wave propagation losses. The spin wave evolution was mapped with a time and spaced resolved inductive magneto-dynamic prove system. The experiment was carried out using a uniform sample of single-crystal YIG film grown on a gallium-gadolinium garnet (GGG) substrate. The 2mm-wide, 20mm-long and 6microns-thick YIG strip was saturated with an external magnetic field enabling the set up for the propagation of magneto-static surface waves. This work was supported by the UNAM-DGAPA-PAPIIT IA100413.

  15. Effect of the magnon dispersion on the longitudinal spin Seebeck effect in yttrium iron garnets

    Science.gov (United States)

    Jin, Hyungyu; Boona, Stephen R.; Yang, Zihao; Myers, Roberto C.; Heremans, Joseph P.

    2015-08-01

    We study the temperature dependence of the longitudinal spin Seebeck effect (LSSE) in an yttrium iron garnet Y3F e5O12 (YIG)/Pt system for samples of different thicknesses. In this system, the thermal spin torque is magnon driven. The LSSE signal peaks at a specific temperature that depends on the YIG sample thickness. We also observe freeze-out of the LSSE signal at high magnetic fields, which we attribute to the opening of an energy gap in the magnon dispersion. We observe partial freeze-out of the LSSE signal even at room temperature, where kBT is much larger than the gap. This suggests that a subset of the magnon population with an energy below kBTC (TC˜40 K ) contributes disproportionately to the LSSE; at temperatures above TC, we label these magnons subthermal magnons. The T dependence of the LSSE at temperatures below the maximum is interpreted in terms of an empirical model that ascribes most of the temperature dependence to that of the thermally driven magnon flux, which is related to the details of the magnon dispersion.

  16. Subthermal-magnon-driven longitudinal spin Seebeck effect in yttrium iron garnets (YIG)

    Science.gov (United States)

    Jin, Hyungyu; Boona, Stephen; Yang, Zihao; Myers, Roberto; Heremans, Joseph

    2015-03-01

    Since its discovery in 2008, the spin Seebeck effect (SSE) has intrigued many interesting research all around the world, which has led to the birth of a new field of research, called ``spin-caloritronics''. Of the two different experimental configurations used for detecting SSE, the longitudinal geometry (LSSE) seems to be generally accepted. The yttrium iron garnet (YIG) / Pt bilayer structure has been most commonly used for LSSE experiments because absence of electrons in YIG excludes contaminations from other thermomagnetic effects. The dependence of the LSSE on YIG film thickness and on temperature have been reported, but not yet both together. Here we present experimental data on the temperature dependence of LSSE in Pt/YIG below room temperature in systems in which the thickness of YIG varies. Detailed discussion is given on the experimental results, with emphasis on the role of subthermal-magnons in the temperature dependence of LSSE in the YIG/Pt system. Work supported by the AFOSR-MURI #FA9550-10-1-0533 and the ARO-MURI #W911NF-14-1-0016.

  17. Thermalization of magnons in yttrium-iron garnet: nonequilibrium functional renormalization group approach

    Energy Technology Data Exchange (ETDEWEB)

    Hick, Johannes; Rueckriegel, Andreas; Kopietz, Peter [Institut fuer Theoretische Physik, Goethe Universitaet Frankfurt am Main (Germany); Kloss, Thomas [Laboratoire de Physique et Modelisation des Milieux Condense, CNRS and Universite Joseph Fourier, Grenoble (France)

    2013-07-01

    Using a nonequilibrium functional renormalization group (FRG) approach we calculate the time evolution of the momentum distribution of a magnon gas in contact with a thermal phonon bath. As a cutoff for the FRG procedure we use a hybridization parameter Λ giving rise to an artificial damping of the phonons. Within our truncation of the FRG flow equations the time evolution of the magnon distribution is obtained from a rate equation involving cutoff-dependent nonequilibrium self-energies, which in turn satisfy FRG flow equations depending on cutoff-dependent transition rates. Our approach goes beyond the Born collision approximation and takes the feedback of the magnons on the phonons into account. We use our method to calculate the thermalization of a quasi two-dimensional magnon gas in the magnetic insulator yttrium-iron garnet after a highly excited initial state has been generated by an external microwave field. In this material interactions which do not conserve the magnon particle number are present and are considered in our approach.

  18. The effect of yttrium substitution on the magnetic properties of magnetite nanoparticles

    Science.gov (United States)

    Mozaffari, M.; Amighian, J.; Tavakoli, R.

    2015-04-01

    Superparamagnetic Y-substituted magnetite (YxFe3-xO4,with x=0.00, 0.10, 0.15, 0.20 and 0.40) nanoparticles were synthesized via hydrothermal reduction route in the presence of citric acid. The synthesized nanoparticles were characterized by X-ray diffraction (XRD) analysis, Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FESEM), vibrating sample magnetometry (VSM) and gradient field thermomagnetic measurement. The results showed that a minimum amount of citric acid is required to obtain single phase Y-substituted magnetite nanoparticles. Citric acid acts as a modulator and reducing agent in the formation of spinel structure and controls nanoparticle size and crystallinity. Mean crystallite sizes of the single-phase powders were estimated by Williamson-Hall method. Curie temperature measurement of the samples shows that as yttrium content increases, the Curie temperature decreases. Magnetic measurements show that the saturation magnetization of the samples decreases as x increases up to 0.15 and then increases to x=0.20 and finally decreases again for x=0.40.

  19. Yttrium Iron Garnet Thin Films with Very Low Damping Obtained by Recrystallization of Amorphous Material.

    Science.gov (United States)

    Hauser, Christoph; Richter, Tim; Homonnay, Nico; Eisenschmidt, Christian; Qaid, Mohammad; Deniz, Hakan; Hesse, Dietrich; Sawicki, Maciej; Ebbinghaus, Stefan G; Schmidt, Georg

    2016-02-10

    We have investigated recrystallization of amorphous Yttrium Iron Garnet (YIG) by annealing in oxygen atmosphere. Our findings show that well below the melting temperature the material transforms into a fully epitaxial layer with exceptional quality, both structural and magnetic. In ferromagnetic resonance (FMR) ultra low damping and extremely narrow linewidth can be observed. For a 56 nm thick layer a damping constant of α = (6.15 ± 1.50) · 10(-5) is found and the linewidth at 9.6 GHz is as small as 1.30 ± 0.05 Oe which are the lowest values for PLD grown thin films reported so far. Even for a 20 nm thick layer a damping constant of α = (7.35 ± 1.40) · 10(-5) is found which is the lowest value for ultrathin films published so far. The FMR linewidth in this case is 3.49 ± 0.10 Oe at 9.6 GHz. Our results not only present a method of depositing thin film YIG of unprecedented quality but also open up new options for the fabrication of thin film complex oxides or even other crystalline materials.

  20. Microstructural evolution and some mechanical properties of nanosized yttrium oxide dispersion strengthened 13Cr steel

    Science.gov (United States)

    Tich Nguyen, Van; Phuong Doan, Dinh; BaoTrung Tran, Tran; Duong Luong, Van; Nguyen, Van An; Phan, Anh Tu

    2010-09-01

    Oxide dispersion strengthened (ODS) steels, manufactured by a mechanical alloying method, during the past few years, appear to be promising candidates for structural applications in nuclear power plants. The purpose of this work is to elaborate the manufacturing processes of ODS 13Cr steel with the addition of 1.0 wt% yttrium oxide through the powder metallurgy route using the high energy ball mill. Microstructural analysis by scanning electron microscopy (SEM), x-ray diffraction (XRD) and hardness testing have been used to optimize the technological parameters of milling, hot isostatic pressing and heat-treatment processes. The steel hardness increases with decreasing particle size of 13Cr ODS steel. The best hardness was obtained from more than 70 h of milling in the two tanks planetary ball mill or 30 h of milling in the one tank planetary ball mill and hot isostatic pressing at 1150 °C . The particle size of the steel is less than 100 nm, and the density and hardness are about 7.3 g cm-3 and 490 HB, respectively. Report submitted to the 5th International Workshop on Advanced Materials Science and Nanotechnology IWAMSN, Hanoi, 9-12 November 2010.

  1. Synthesis and Characterization of A Polynuclear Yttrium Trifluoroethoxide and Its Activity for Oligomerization of Phenyl Isocyanate

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A polynuclear yttrium trifluoroethoxide was synthesized and its activity for the oligomerization of phenyl isocyanate was tested. Reaction of anhydrous YCl3 with CF3CH2ONa in a 1:3 molar ratio in THF at room temperature, after workup, gave complex 1 as colorless crystals. The composition of complex 1 is [Y(OCH2CF3)3]6ONa2(THF)12, which was identified by elemental analysis and 1H NMR. Further X-ray structure determination reveals that complex 1 is a polynuclear ion pair compound, [Y6(μ6-O)(OCH2CF3)18]2-[Na(THF)6]+2 (1). The crystal data of complex 1 are trigonal, P-3 space group, a=1.78440(14) nm, b=1.78440(14) nm, c=1.27395(12) nm, γ=120°, V=3.5129(5) nm3, Z=1, Dc=1.607 mg·m-3, μ=2.591 mm-1 (Mo Kα), F(000)=1710, R=0.067, wR=0.182. Preliminary results demonstrated that complex 1 is a highly effective catalyst for the oligomerization of phenyl isocyanate.

  2. Effect of Low Concentration of Yttrium on Physiological Characteristics of Cucumber (Cucumis Sativus L.)

    Institute of Scientific and Technical Information of China (English)

    Wang Shuo; Chen Dan; Qin Zhaojiang; Dong Zhenyu; Ju Mingchao; Xie Bingning

    2007-01-01

    There is no doubt that rare earth elements stand an important position among the essential elements of plant growth and it is long time since they are first used as plant growth promoters. Given their effects on microstructure, most reports are focused on the toxicology rather than promotion. Using cucumis sativus L. (Jin Chun No.5) as experiment material, we try to find out the nutritional effects of low Y3+ concentrations on cucumber seedlings' leaves. The present paper suggests that the rare earth elements act as micronutrients at low concentrations while they give rise to toxicity at high concentration. Benefits defeat toxicity with concentration ranging from 5 to 25μmol·L-1. Through careful study, at the Y (N03)3 concentration of 10μmol·L1 the content of chlorophyll as well as the activities of SOD, Cu-Zn SOD and the POD are the highest. It indicates 10μmol·L-1 is the optimum concentration of yttrium for promoting the cucumber growth.

  3. Epitaxial and non-epitaxial platinum, palladium and silver films on yttrium-stabilised zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Beck, Gesa, E-mail: gesa.beck@physik.uni-augsburg.de [Institute of Physics, University Augsburg, Universitaetsstrasse 1a, 86159 Augsburg (Germany); Bachmann, Christoph [Institute of Physical Chemistry, Justus-Liebig-University Giessen, Heinrich-Buff-Ring 58, 35392 Giessen (Germany); Bretzler, Rita [Research Institute Precious Metals & Metals Chemistry, Katharinenstrasse 17, 73525 Schwaebisch Gmuend (Germany); Kmeth, Ralf [Institute of Physics, University Augsburg, Universitaetsstrasse 1a, 86159 Augsburg (Germany)

    2015-05-05

    Platinum, palladium and silver films have been prepared on differently orientated YSZ (yttrium-stabilised zirconia) substrates by PLD (pulsed laser deposition). The deposition temperatures for platinum were 200 °C and 400 °C, whereas palladium and silver were deposited only at 200 °C. The microstructure of the films depends on the particular metal, on the orientation of the substrate and on the deposition temperature. Platinum – deposited at 400 °C – forms single crystalline, epitaxial (111), (311) and (110) orientated as well as (111) orientated polycrystalline films. Platinum, palladium and silver – deposited at 200 °C – always form (111) orientated and polycrystalline films, in some cases also with a fraction of epitaxial grown grains. The formed microstructures were discussed on the basis of interface and surface energy minimization and structure zone models. - Highlights: • Pt, Pd and Ag films are prepared on differently orientated YSZ. • Substrate orientation and deposition temperature influences the microstructure. • Pt forms epitaxial and polycrystalline films. • Pd and Ag form polycrystalline films, sometimes with epitaxial grown grains. • The formed microstructures are described by energy minimization.

  4. Oxidation kinetics of aluminum diboride

    Energy Technology Data Exchange (ETDEWEB)

    Whittaker, Michael L., E-mail: michaelwhittaker2016@u.northwestern.edu [Department of Materials Science and Engineering, University of Utah, 122S. Central Campus Drive, Salt Lake City, UT 84112 (United States); Sohn, H.Y. [Department of Metallurgical Engineering, University of Utah, 135S 1460 E, Rm 00412, Salt Lake City, UT 84112 (United States); Cutler, Raymond A. [Ceramatec, Inc., 2425S. 900W., Salt Lake City, UT 84119 (United States)

    2013-11-15

    The oxidation characteristics of aluminum diboride (AlB{sub 2}) and a physical mixture of its constituent elements (Al+2B) were studied in dry air and pure oxygen using thermal gravimetric analysis to obtain non-mechanistic kinetic parameters. Heating in air at a constant linear heating rate of 10 °C/min showed a marked difference between Al+2B and AlB{sub 2} in the onset of oxidation and final conversion fraction, with AlB{sub 2} beginning to oxidize at higher temperatures but reaching nearly complete conversion by 1500 °C. Kinetic parameters were obtained in both air and oxygen using a model-free isothermal method at temperatures between 500 and 1000 °C. Activation energies were found to decrease, in general, with increasing conversion for AlB{sub 2} and Al+2B in both air and oxygen. AlB{sub 2} exhibited O{sub 2}-pressure-independent oxidation behavior at low conversions, while the activation energies of Al+2B were higher in O{sub 2} than in air. Differences in the composition and morphology between oxidized Al+2B and AlB{sub 2} suggested that Al{sub 2}O{sub 3}–B{sub 2}O{sub 3} interactions slowed Al+2B oxidation by converting Al{sub 2}O{sub 3} on aluminum particles into a Al{sub 4}B{sub 2}O{sub 9} shell, while the same Al{sub 4}B{sub 2}O{sub 9} developed a needle-like morphology in AlB{sub 2} that reduced oxygen diffusion distances and increased conversion. The model-free kinetic analysis was critical for interpreting the complex, multistep oxidation behavior for which a single mechanism could not be assigned. At low temperatures, moisture increased the oxidation rate of Al+2B and AlB{sub 2}, but both appear to be resistant to oxidation in cool, dry environments. - Graphical abstract: Isothermal kinetic data for AlB{sub 2} in air, showing a constantly decreasing activation energy with increasing conversion. Model-free analysis allowed for the calculation of global kinetic parameters despite many simultaneous mechanisms occurring concurrently. (a) Time

  5. Wastewater sludge dewaterability enhancement using hydroxyl aluminum conditioning: Role of aluminum speciation.

    Science.gov (United States)

    Cao, Bingdi; Zhang, Weijun; Wang, Qiandi; Huang, Yangrui; Meng, Chenrui; Wang, Dongsheng

    2016-11-15

    Chemical conditioning is one of the most important processes for improve the performance of sludge dewatering device. Aluminum salt coagulant has been widely used in wastewater and sludge treatment. It is generally accepted that pre-formed speciation of aluminum salt coagulants (ASC) has an important influence on coagulation/flocculation performance. In this study, the interaction mechanisms between sludge particles and aluminum salt coagulants with different speciation of hydroxy aluminum were investigated by characterizing the changes in morphological and EPS properties. It was found that middle polymer state aluminum (Alb) and high polymer state aluminum (Alc) performed better than monomer aluminum and oligomeric state aluminum (Ala) in reduction of specific resistance to filtration (SRF) and compressibility of wastewater sludge due to their higher charge neutralization and formed more compact flocs. Sludge was significantly acidified after addition Ala, while pH was much more stable under Alb and Alc conditioning due to their hydrolysis stability. The size of sludge flocs conditioned with Alb and Alc was small but flocs structure was denser and more compact, and floc strength is higher, while that formed from Ala is relatively large, but floc structure was loose, floc strength is relatively lower. Scanning environmental microscope analysis revealed that sludge flocs conditioned by Alb and Alc (especially PAC2.5 and Al13) exhibited obvious botryoidal structure, this is because sludge flocs formed by Alb and Alc were more compact and floc strength is high, it was easy generated plentiful tiny channels for water release. In addition, polymeric aluminum salt coagulant (Alb, Alc) had better performance in compressing extracellular polymeric substances (EPS) structure and removing sticky protein-like substances from soluble EPS fraction, contributing to improvement of sludge filtration performance. Therefore, this study provides a novel solution for improving sludge

  6. Kinetics of aluminum lithium alloys

    Science.gov (United States)

    Pletcher, Ben A.

    2009-12-01

    Aluminum lithium alloys are increasingly used in aerospace for their high strength-to-weight ratio. Additions of lithium, up to 4.2 wt% decrease the alloy density while increasing the modulus and yield strength. The metastable, second phase Al3Li or delta' is intriguing, as it remains spherical and coherent with the matrix phase, alpha, well into the overaged condition. Small interfacial strain energy allows these precipitates to remain spherical for volume fractions (VV ) of delta' less than 0.3, making this alloy system ideal for investigation of late-stage coarsening phenomena. Experimental characterization of three binary Al-Li alloys are presented as a critical test of diffusion screening theory and multi-particle diffusion simulations. Quantitative transmission electron microscopy is used to image the precipitates directly using the centered dark-field technique. Images are analyzed autonomously within a novel Matlab function that determines the center and size of each precipitate. Particle size distribution, particle growth kinetics, and maximum particle size are used to track the precipitate growth and correlate with the predictions of screening theory and multi-particle diffusion simulations. This project is the first extensive study of Al-Li alloys, in over 25 years, applying modern transmission electron microscopy and image analysis techniques. Previous studies sampled but a single alloy composition, and measured far fewer precipitates. This study investigates 3 alloys with volume fractions of the delta precipitates, VV =0.1-0.27, aged at 225C for 1 to 10 days. More than 1000 precipitates were sampled per aging time, creating more statistically significant data. Experimental results are used to test the predictions based on diffusion screening theory and multi-particle aging simulations. (Full text of this dissertation may be available via the University of Florida Libraries web site. Please check http://www.uflib.ufl.edu/etd.html)

  7. Geochemistry of rare earth elements and yttrium in a Ge-poor coal from the Wulantuga ore deposit, Inner Mongolia, North China

    Institute of Scientific and Technical Information of China (English)

    Jingjing Liu; Yaofa Jiang; Panpan Xie; Qingqian Li

    2014-01-01

    This paper reports data of yttrium and rare earth (REY, or REE if Y is considered) in a Ge-poor (the average value of Ge is 0.57μg/g) coal from the Wulantuga ore deposit, middle Inner Mongolia, northern China. The contents of yttrium and rare earth in six coal samples of the Wulantuga ore deposit were detected by inductively coupled plasma mass spectrometry. The content of yttrium and rare earth in the study area varies from 5.88 to 119.19μg/g, with an average of 61.85μg/g, similar to the average value for world coals. The light-REY and heavy-REY enrichments are the two major REY-enrichment types of the Ge-poor coal from the Wulantuga ore deposit, and the top and bottom parts of the coal seam have a higher content of REY than the middle part. The sources of yttrium and rare earth in the Ge-poor coal of Wulantuga may be mainly associated with terrigenous materials and natural waters enriched in yttrium and rare earth.

  8. Formation and properties of stabilized aluminum nanoparticles.

    Science.gov (United States)

    Meziani, Mohammed J; Bunker, Christopher E; Lu, Fushen; Li, Heting; Wang, Wei; Guliants, Elena A; Quinn, Robert A; Sun, Ya-Ping

    2009-03-01

    The wet-chemical synthesis of aluminum nanoparticles was investigated systematically by using dimethylethylamine alane and 1-methylpyrrolidine alane as precursors and molecules with one or a pair of carboxylic acid groups as surface passivation agents. Dimethylethylamine alane was more reactive, capable of yielding well-defined and dispersed aluminum nanoparticles. 1-Methylpyrrolidine alane was less reactive and more complex in the catalytic decomposition reaction, for which various experimental parameters and conditions were used and evaluated. The results suggested that the passivation agent played dual roles of trapping aluminum particles to keep them nanoscale during the alane decomposition and protecting the aluminum nanoparticles postproduction from surface oxidation and that an appropriate balance between the rate of alane decomposition (depending more sensitively on the reaction temperature) and the timing in the introduction of the passivation agent into the reaction mixture was critical to the desired product mixes and/or morphologies. Some fundamental and technical issues on the alane decomposition and the protection of the resulting aluminum nanoparticles are discussed.

  9. Evaluation of Aluminum in Iranian Consumed Tea

    Directory of Open Access Journals (Sweden)

    Alireza Asgari

    2008-01-01

    Full Text Available Introduction: Black tea leaf is one of the most important sources of Aluminum in dietary. Therefore this research was conducted to assess the amount of Aluminum in Iranian tea infusion. Methods: To assess Aluminum in Iranian consumed tea, 27 tea samples were analyzed for Al concentration for 10 and 60 min infusion, aluminum concentration was measured with atomic absorption and the results were analyzed by SPSS.13 version. Results: The results showed that minimum and maximum concentration of Al in tea infusion for 10 min infusion was 1.59 and 18.60 mg.L-1 respectively in this regard Baroti and Bamdad tea show the highest and lowest concentration respectively in term of Al, Also Statistical analysis with pair T-test showed that infusion time doesn,t significantly effects on aluminum leaching into infusion (P>0.05. Calculation of percentage "available" Al to the human system showed that 1 L of tea can provide 17.68 % of the daily dietary intake of Al, the percentage "available" for absorption in the intestine is only 8.49 % for overall mean Al concentration. Conclusion: Therefore based on our results, tea consumption in medium values cannot cause toxic effects on human. Although it is necessary to note that tea consumption might be toxic because of effects on people with absorption or secretion problems

  10. ALUMINUM AND CHROMIUM LEACHING WORKSHOP WHITEPAPER

    Energy Technology Data Exchange (ETDEWEB)

    McCabe, D; Jeff Pike, J; Bill Wilmarth, B

    2007-04-25

    A workshop was held on January 23-24, 2007 to discuss the status of processes to leach constituents from High Level Waste (HLW) sludges at the Hanford and Savannah River Sites. The objective of the workshop was to examine the needs and requirements for the HLW flowsheet for each site, discuss the status of knowledge of the leaching processes, communicate the research plans, and identify opportunities for synergy to address knowledge gaps. The purpose of leaching of non-radioactive constituents from the sludge waste is to reduce the burden of material that must be vitrified in the HLW melter systems, resulting in reduced HLW glass waste volume, reduced disposal costs, shorter process schedules, and higher facility throughput rates. The leaching process is estimated to reduce the operating life cycle of SRS by seven years and decrease the number of HLW canisters to be disposed in the Repository by 1000 [Gillam et al., 2006]. Comparably at Hanford, the aluminum and chromium leaching processes are estimated to reduce the operating life cycle of the Waste Treatment Plant by 20 years and decrease the number of canisters to the Repository by 15,000-30,000 [Gilbert, 2007]. These leaching processes will save the Department of Energy (DOE) billions of dollars in clean up and disposal costs. The primary constituents targeted for removal by leaching are aluminum and chromium. It is desirable to have some aluminum in glass to improve its durability; however, too much aluminum can increase the sludge viscosity, glass viscosity, and reduce overall process throughput. Chromium leaching is necessary to prevent formation of crystalline compounds in the glass, but is only needed at Hanford because of differences in the sludge waste chemistry at the two sites. Improving glass formulations to increase tolerance of aluminum and chromium is another approach to decrease HLW glass volume. It is likely that an optimum condition can be found by both performing leaching and improving

  11. Aluminum phosphate ceramics for waste storage

    Science.gov (United States)

    Wagh, Arun; Maloney, Martin D

    2014-06-03

    The present disclosure describes solid waste forms and methods of processing waste. In one particular implementation, the invention provides a method of processing waste that may be particularly suitable for processing hazardous waste. In this method, a waste component is combined with an aluminum oxide and an acidic phosphate component in a slurry. A molar ratio of aluminum to phosphorus in the slurry is greater than one. Water in the slurry may be evaporated while mixing the slurry at a temperature of about 140-200.degree. C. The mixed slurry may be allowed to cure into a solid waste form. This solid waste form includes an anhydrous aluminum phosphate with at least a residual portion of the waste component bound therein.

  12. NASA-427: A New Aluminum Alloy

    Science.gov (United States)

    Nabors, Sammy A.

    2015-01-01

    NASA's Marshall Space Flight Center researchers have developed a new, stronger aluminum alloy, ideal for cast aluminum products that have powder or paint-baked thermal coatings. With advanced mechanical properties, the NASA-427 alloy shows greater tensile strength and increased ductility, providing substantial improvement in impact toughness. In addition, this alloy improves the thermal coating process by decreasing the time required for heat treatment. With improvements in both strength and processing time, use of the alloy provides reduced materials and production costs, lower product weight, and better product performance. The superior properties of NASA-427 can benefit many industries, including automotive, where it is particularly well-suited for use in aluminum wheels.

  13. Dynamic recrystallization behavior of commercial pure aluminum

    Institute of Scientific and Technical Information of China (English)

    LI Hui-zhong; ZHANG Xin-ming; CHEN Ming-an; LIU Zi-juan

    2006-01-01

    The flow stress feature and microstructure evolvement of a commercial pure aluminum were investigated by compression on Gleeble-1500 dynamic materials test machine. Optical microscopy (OM) and transmission electron microscopy (TEM) were applied to analyze the deformation microstructure of the commercial pure aluminum.The results show that the flow stress tends to be constant after a peak value and the dynamic recovery occurs when the deformation temperatures is 220 ℃ with the strain rate of 0.01 s-1; while the dynamic recrystallization occurs when the deformation temperature is higher than 380 ℃, and the flow stress exhibits a single peak at 460 ℃ with different strain rates from 0.001 s-1 to 1 s-1, and continuous dynamic recrystallization and geometric dynamic recrystallization occur during the hot compression of the commercial pure aluminum.

  14. Lithium-aluminum-magnesium electrode composition

    Science.gov (United States)

    Melendres, Carlos A.; Siegel, Stanley

    1978-01-01

    A negative electrode composition is presented for use in a secondary, high-temperature electrochemical cell. The cell also includes a molten salt electrolyte of alkali metal halides or alkaline earth metal halides and a positive electrode including a chalcogen or a metal chalcogenide as the active electrode material. The negative electrode composition includes up to 50 atom percent lithium as the active electrode constituent and a magnesium-aluminum alloy as a structural matrix. Various binary and ternary intermetallic phases of lithium, magnesium, and aluminum are formed but the electrode composition in both its charged and discharged state remains substantially free of the alpha lithium-aluminum phase and exhibits good structural integrity.

  15. Air-Impregnated Nanoporous Anodic Aluminum Oxide Layers for Enhancing the Corrosion Resistance of Aluminum.

    Science.gov (United States)

    Jeong, Chanyoung; Lee, Junghoon; Sheppard, Keith; Choi, Chang-Hwan

    2015-10-13

    Nanoporous anodic aluminum oxide layers were fabricated on aluminum substrates with systematically varied pore diameters (20-80 nm) and oxide thicknesses (150-500 nm) by controlling the anodizing voltage and time and subsequent pore-widening process conditions. The porous nanostructures were then coated with a thin (only a couple of nanometers thick) Teflon film to make the surface hydrophobic and trap air in the pores. The corrosion resistance of the aluminum substrate was evaluated by a potentiodynamic polarization measurement in 3.5 wt % NaCl solution (saltwater). Results showed that the hydrophobic nanoporous anodic aluminum oxide layer significantly enhanced the corrosion resistance of the aluminum substrate compared to a hydrophilic oxide layer of the same nanostructures, to bare (nonanodized) aluminum with only a natural oxide layer on top, and to the latter coated with a thin Teflon film. The hydrophobic nanoporous anodic aluminum oxide layer with the largest pore diameter and the thickest oxide layer (i.e., the maximized air fraction) resulted in the best corrosion resistance with a corrosion inhibition efficiency of up to 99% for up to 7 days. The results demonstrate that the air impregnating the hydrophobic nanopores can effectively inhibit the penetration of corrosive media into the pores, leading to a significant improvement in corrosion resistance.

  16. The Effect of Anodic Oxide Films on the Nickel-Aluminum Reaction in Aluminum Braze Sheet

    Science.gov (United States)

    Tadgell, Colin A.; Wells, Mary A.; Corbin, Stephen F.; Colley, Leo; Cheadle, Brian; Winkler, Sooky

    2017-03-01

    The influence of an anodic oxide surface film on the nickel-aluminum reaction at the surface of aluminum brazing sheet has been investigated. Samples were anodized in a barrier-type solution and subsequently sputtered with nickel. Differential scanning calorimetry (DSC) and metallography were used as the main investigative techniques. The thickness of the anodic film was found to control the reaction between the aluminum substrate and nickel coating. Solid-state formation of nickel-aluminum intermetallic phases occurred readily when a relatively thin oxide film (13 to 25 nm) was present, whereas intermetallic formation was suppressed in the presence of thicker oxides ( 60 nm). At an intermediate oxide film thickness of 35 nm, the Al3Ni phase formed shortly after the initiation of melting in the aluminum substrate. Analysis of DSC traces showed that formation of nickel-aluminum intermetallic phases changed the melting characteristics of the aluminum substrate, and that the extent of this change can be used as an indirect measure of the amount of nickel incorporated into the intermetallic phases.

  17. Reducing aluminum dust explosion hazards: case study of dust inerting in an aluminum buffing operation.

    Science.gov (United States)

    Myers, Timothy J

    2008-11-15

    Metal powders or dusts can represent significant dust explosion hazards in industry, due to their relatively low ignition energy and high explosivity. The hazard is well known in industries that produce or use aluminum powders, but is sometimes not recognized by facilities that produce aluminum dust as a byproduct of bulk aluminum processing. As demonstrated by the 2003 dust explosion at aluminum wheel manufacturer Hayes Lemmerz, facilities that process bulk metals are at risk due to dust generated during machining and finishing operations [U.S. Chemical Safety and Hazard Investigation Board, Investigation Report, Aluminum Dust Explosion Hayes Lemmerz International, Inc., Huntington, Indiana, Report No. 2004-01-I-IN, September 2005]. Previous studies have shown that aluminum dust explosions are more difficult to suppress with flame retardants or inerting agents than dust explosions fueled by other materials such as coal [A.G. Dastidar, P.R. Amyotte, J. Going, K. Chatrathi, Flammability limits of dust-minimum inerting concentrations, Proc. Saf. Progr., 18-1 (1999) 56-63]. In this paper, an inerting method is discussed to reduce the dust explosion hazard of residue created in an aluminum buffing operation as the residue is generated. This technique reduces the dust explosion hazard throughout the buffing process and within the dust collector systems making the process inherently safer. Dust explosion testing results are presented for process dusts produced during trials with varying amounts of flame retardant additives.

  18. Interaction of catechins with aluminum in vitro

    Institute of Scientific and Technical Information of China (English)

    唐德松; 沈生荣; 陈勋; 张玉艳; 许重阳

    2004-01-01

    Tea is one of the most popular beverages, consumed by over two thirds of the world's population; but the aluminum accumulation property of tea plant is becoming the focus of many researches because of aluminum's known adverse effect on human health. Investigation of the interactions of catechins with A13+ showed that during the interaction of catechins with A13+, the UV-vis spectrum of catechins was changed. Absorption of EGCG at 274 nm decreased and increased at 322 nm; EC and C's at 278 nm changed little. The ratio of A13+ to EGCG was 1:1 in pH 5.0 buffer solution; in pH 6.2 buffer solution, the ratio in the A1-EGCG complex was 1:1. Interestingly, while the ratio reached to over 2, after the complex of A1-EGCG started polymerization, the ratio in the polymer was 2:1. In pH 6.2 buffer solution, the complex behavior of C with A13+ was the same as that of EGCG, with a little difference for EC. When the ratio of A13+ to EC was1. It was found that the ratio of A13+ to EC in the polymer was 1:1. Polymerization of A1-catechin complexes might reduce aluminum absorption in the intestine. Kow value was also employed to study the properties of aluminum species in tea infusion (at gastric and intestine pH condition) and the effect of catechins and tea polyphenols on Kow in buffer solution. Results showed that Kow value rose much higher at the intestine pH than at the gastric pH. Tea polyphenols and catechins could greatly reduce aluminum Kow value in acetic buffer,indicating that these compounds may reduce aluminum absorption during tea intake.

  19. Interaction of catechins with aluminum in vitro

    Institute of Scientific and Technical Information of China (English)

    唐德松; 沈生荣; 陈勋; 张玉艳; 许重阳

    2004-01-01

    Tea is one of the most popular beverages, consumed by over two thirds of the world's population; but the aluminum accumulation property of tea plant is becoming the focus of many researches because of aluminum's known adverse effect on human health. Investigation of the interactions of catechins with Al3+ showed that during the interaction of catechins with Al3+, the UV-vis spectrum of catechins was changed. Absorption of EGCG at 274 nm decreased and increased at 322 nm; EC and C's at 278 nm changed little. The ratio of Al3+ to EGCG was 1:1 in pH 5.0 buffer solution; in pH 6.2 buffer solution, the ratio in the Al-EGCG complex was 1:1. Interestingly, while the ratio reached to over 2, after the complex of Al-EGCG started polymerization, the ratio in the polymer was 2:1. In pH 6.2 buffer solution, the complex behavior of C with Al3+ was the same as that of EGCG, with a little difference for EC. When the ratio of Al3+ to EC was 1. It was found that the ratio of Al3+ to EC in the polymer was 1:1. Polymerization of Al-catechin complexes might reduce aluminum absorption in the intestine. Kow value was also employed to study the properties of aluminum species in tea infusion (at gastric and intestine pH condition) and the effect of catechins and tea polyphenols on Kow in buffer solution. Results showed that Kow value rose much higher at the intestine pH than at the gastric pH. Tea polyphenols and catechins could greatly reduce aluminum Kow value in acetic buffer, indicating that these compounds may reduce aluminum absorption during tea intake.

  20. Effect of Electrolyte on the Dissolution of Aluminum from Acid Sois and the Distribution of Aluminum Forms in Soil Solution

    Institute of Scientific and Technical Information of China (English)

    XURENKOU; JIGUOLIANG

    1997-01-01

    KCl,CaCl2,NH4Cl,NaCl,K2SO4 and KF solutions were used for studying the effects of cations and anions on the dissolution of aluminum and the distribution of aluminum forms respectively.Power of exchanging and releasing aluminum of four kinds of cations was in the decreasing order Ca2+>K+>NH4+>Na+,The dissolution of aluminum increased with the cation concentration.The adsorption affinity of various soils fro aluminum was different.The aluminum in the soil with a stronger adsorption affinity was diffcult to be exchanged and released by cations.The Al-F complexes were main species of inorganic aluminum at a low concentration of cations,while Al3+ became major species of inorganic aluminum at a hiht concentration of cations .The results on the effct of anions indicated that the concentrations of total aluminum,three kinds of inorganc aluminum(Al3+,Al-F and Al-OH complexes) and organic aluminum complexes(Al-OM) when SO42- was added into soil suspension were lower than those when Cl- was added.The dissolution of aluminum from soils and the distribution of aluminum forms in solution were affected by the adsorption of F- on the soil.For soils with strong affinity for F-,the concentrations of the three inorganic aluminum species in soil solution after addition of F- were lower than those after addition of Cl-;but for soils with weak affinity for F-,the concentrations of Al3+ and Al-OM were lower and the concentrations of Al-F complexes and total inorganic aluminum after addition of F- were higher than those after addition of Cl- .The increase of F- concentration in soil solution accelerated the dissolution of aluminum from soils.

  1. Composite purification technology and mechanism of recycled aluminum alloys

    Institute of Scientific and Technical Information of China (English)

    房文斌; 耿耀宏; 安阁英; 叶荣茂

    2002-01-01

    Iron-rich inclusions in aluminum alloys can be effectively removed by composite purification of sedimentation and filtration technology.The results show that the purposed method has no negative effects on aluminum alloys and obviously improve their mechanical properties.

  2. Understanding Aspects of Aluminum Exposure in Alzheimer's Disease Development.

    Science.gov (United States)

    Kandimalla, Ramesh; Vallamkondu, Jayalakshmi; Corgiat, Edwin B; Gill, Kiran Dip

    2016-03-01

    Aluminum is a ubiquitously abundant nonessential element. Aluminum has been associated with neurodegenerative diseases such as Alzheimer's disease (AD), amyotrophic lateral sclerosis, and dialysis encephalopathy. Many continue to regard aluminum as controversial although increasing evidence supports the implications of aluminum in the pathogenesis of AD. Aluminum causes the accumulation of tau protein and Aβ protein in the brain of experimental animals. Aluminum induces neuronal apoptosis in vivo and in vitro, either by endoplasmic stress from the unfolded protein response, by mitochondrial dysfunction, or a combination of them. Some, people who are exposed chronically to aluminum, either from through water and/or food, have not shown any AD pathology, apparently because their gastrointestinal barrier is more effective. This article is written keeping in mind mechanisms of action of aluminum neurotoxicity with respect to AD.

  3. [Aluminum induces chromosome aberrations in wheat root meristem cells].

    Science.gov (United States)

    Bulanova, N V; Synzynys, B I; Koz'min, G V

    2001-12-01

    The yield and pattern of chromosome structure aberrations in wheat seedlings treated with aluminum nitrate and aluminum sulfate at various concentrations have been determined by the anaphase method. Aluminum has a genotoxic effect causing genome, chromatid, and chromosome aberrations in apical root meristem cells. The relationship between the total yield of structural mutations and the aluminum concentration follows a bell-shaped curve. The mutagenic activity of aluminum nitrate peaks at 10(-3) mg/ml, which is twice as high as the permissible concentration limit (PCL) of aluminum in potable water. The maximum of the mutagenic activity of aluminum sulfate is observed at 5 x 10(-4) mg/ml, i.e., one PCL. Tap water boiled for 2 h in an aluminum vessel has virtually no genotoxic effect on wheat cells.

  4. Method of winning aluminum metal from aluminous ore

    Science.gov (United States)

    Loutfy, Raouf O.; Keller, Rudolf; Yao, Neng-Ping

    1981-01-01

    Aluminous ore such as bauxite containing alumina is blended with coke or other suitable form of carbon and reacted with sulfur gas at an elevated temperature. For handling, the ore and coke can be extruded into conveniently sized pellets. The reaction with sulfur gas produces molten aluminum sulfide which is separated from residual solid reactants and impurities. The aluminum sulfide is further increased in temperature to cause its decomposition or sublimation, yielding aluminum subsulfide liquid (AlS) and sulfur gas that is recycled. The aluminum monosulfide is then cooled to below its disproportionation temperature to again form molten aluminum sulfide and aluminum metal. A liquid-liquid or liquid-solid separation, depending on the separation temperature, provides product aluminum and aluminum sulfide for recycle to the disproportionation step.

  5. Anodization process produces opaque, reflective coatings on aluminum

    Science.gov (United States)

    1965-01-01

    Opaque, reflective coatings are produced on aluminum articles by an anodizing process wherein the anodizing bath contains an aqueous dispersion of finely divided insoluble inorganic compounds. These particles appear as uniformly distributed occlusions in the anodic deposit on the aluminum.

  6. Low Mass, Aluminum NOFBX Combustion Chamber Development Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Our team proposes to define a diffusion bonding process for aluminum as an enabling step to ultimately develop an innovative, lightweight, long life, aluminum...

  7. Refined Aluminum Industry Suffers From Deficit and Western Investment Accelerates

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    <正>Under the backdrop of loss of the entire refined aluminum industry,the investment in electrolytic aluminum accelerates.The reporter learnt from a recent survey that,many companies including Shandong Xinfa Group,East Hope

  8. Iron and aluminum in Alzheimer's disease.

    Science.gov (United States)

    Di Lorenzo, Francesco; Di Lorenzo, Berardino

    2013-01-01

    In this case presentation, a woman with high serum levels of aluminum was treated with chelation therapy with deferoxamine and ascorbic acid. This patient was initially bedridden and the clinical situation was complicated by epileptic seizures. After the chelation therapy, the clinical condition was ameliorated and the therapy continued without the correlation to aluminum serum levels. The role of metals in neurodegenerative disorders and the correlation between iron metabolism and amyloid beta peptide are described. This case suggests chelation therapy could represent a promising therapeutic option for this dramatic disease.

  9. Sound absorption property of openpore aluminum foams

    Directory of Open Access Journals (Sweden)

    WANG Fang

    2007-02-01

    Full Text Available This paper presents a study on sound absorption property of aluminum foam by evaluating its sound absorption coefficients using standing wave tube method. Experimental results showed that the average values of sound absorption coefficients (over the test frequency range are all above 0.4, which indicate very good sound absorption property of the aluminum foams. The sound absorption coefficient is affected by frequency and pore structure, and reaches its maximum value at around 1 000 Hz. With the increase of porosity and decrease of cell diameter, the sound absorption coefficient values increase.

  10. Aluminum plasmonic metamaterials for structural color printing.

    Science.gov (United States)

    Cheng, Fei; Gao, Jie; Stan, Liliana; Rosenmann, Daniel; Czaplewski, David; Yang, Xiaodong

    2015-06-01

    We report a structural color printing platform based on aluminum plasmonic metamaterials supporting near perfect light absorption and narrow-band spectral response tunable across the visible spectrum to realize high-resolution, angle-insensitive color printing with high color purity and saturation. Additionally, the fabricated metamaterials can be protected by a transparent polymer thin layer for ambient use with further improved color performance. The demonstrated structural color printing with aluminum plasmonic metamaterials offers great potential for relevant applications such as security marking and information storage.

  11. Development of deep drawn aluminum piston tanks

    Energy Technology Data Exchange (ETDEWEB)

    Whitehead, J.C.; Bronder, R.L.; Kilgard, L.W.; Evans, M.C.; Ormsby, A.E.; Spears, H.R.; Wilson, J.D.

    1990-06-08

    An aluminum piston tank has been developed for applications requiring lightweight, low cost, low pressure, positive-expulsion liquid storage. The 3 liter (183 in{sup 3}) vessel is made primarily from aluminum sheet, using production forming and joining operations. The development process relied mainly on pressurizing prototype parts and assemblies to failure, as the primary source of decision making information for driving the tank design toward its optimum minimum-mass configuration. Critical issues addressed by development testing included piston operation, strength of thin-walled formed shells, alloy choice, and joining the end cap to the seamless deep drawn can. 9 refs., 8 figs.

  12. Modern trends and challenges of development of global aluminum industry

    Directory of Open Access Journals (Sweden)

    M. N. Dudin

    2017-12-01

    Full Text Available This article overviews complex study into modern trends and challenges of development of global aluminum industry. Dynamics, structure, and segmentation of global aluminum market are discussed in terms of systematic analysis. On this basis strategic map of the industry has been plotted and five forces of competition on global aluminum market have been determined which will influence directly on functioning and development of aluminum producing companies.

  13. Sunshine Group Builds High-End Aluminum Product Industrial Base

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    In order to propel development of the aluminum industry to move toward featured,specialized,and ecological directions,Sunlight Sanyuan Aluminum Company plans to expropriate 300 mu of land in Hanjiang District of Putian City,Fujian province,where it plans to construct high-end aluminum product industrial park,introduce the world’s most advanced fully automatic production equipment and technologies for aluminum profile and

  14. Treating and Downstaging Hepatocellular Carcinoma in the Caudate Lobe with Yttrium-90 Radioembolization

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, Saad M. [Northwestern University Feinberg School of Medicine, Robert H. Lurie Comprehensive Cancer Center, Department of Radiology, Section of Interventional Radiology (United States); Kulik, Laura [Northwestern University Feinberg School of Medicine, Department of Medicine, Division of Hepatology (United States); Baker, Talia [Northwestern University Feinberg School of Medicine, Division of Transplant Surgery (United States); Ryu, Robert K. [Northwestern University Feinberg School of Medicine, Robert H. Lurie Comprehensive Cancer Center, Department of Radiology, Section of Interventional Radiology (United States); Mulcahy, Mary F. [Northwestern University Feinberg School of Medicine, Department of Medicine, Division of Hematology and Oncology, Robert H. Lurie Comprehensive Cancer Center (United States); Abecassis, Michael [Northwestern University Feinberg School of Medicine, Division of Transplant Surgery (United States); Salem, Riad; Lewandowski, Robert J., E-mail: r-lewandowski@northwestern.edu [Northwestern University Feinberg School of Medicine, Robert H. Lurie Comprehensive Cancer Center, Department of Radiology, Section of Interventional Radiology (United States)

    2012-10-15

    Purpose: This study was designed to determine the technical feasibility, safety, efficacy, and potential to downstage patients to within transplantation criteria when treating patients with hepatocellular carcinoma (HCC) of the caudate lobe using Y90 radioembolization. Methods: During a 4-year period, 8 of 291 patients treated with radioembolization for unresectable HCC had disease involving the caudate lobe. All patients were followed for treatment-related clinical/biochemical toxicities, serum tumor marker response, and treatment response. Imaging response was assessed with the World Health Organization (WHO) and European Association for the Study of the Liver (EASL) classification schemes. Pathologic response was reported as percent necrosis at explantation. Results: Caudate lobe radioembolization was successfully performed in all eight patients. All patients presented with both cirrhosis and portal hypertension. Half were United Network for Organ Sharing (UNOS) stage T3 (n = 4, 50%). Fatigue was reported in half of the patients (n = 4, 50%). One (13%) grade 3/4 bilirubin toxicity was reported. One patient (13%) showed complete tumor response by WHO criteria, and three patients (38%) showed complete response using EASL guidelines. Serum AFP decreased by more than 50% in most patients (n = 6, 75%). Four patients (50%) were UNOS downstaged from T3 to T2, three of who underwent transplantation. One specimen showed histopathologic evidence of 100% complete necrosis, and two specimens demonstrated greater than 50% necrosis. Conclusions: Radioembolization with yttrium-90 appears to be a feasible, safe, and effective treatment option for patients with unresectable caudate lobe HCC. It has the potential to downstage patients to transplantation.

  15. Yttrium-90 resin microspheres as an adjunct to sorafenib in patients with unresectable hepatocellular carcinoma

    Science.gov (United States)

    Mahvash, Armeen; Murthy, Ravi; Odisio, Bruno C; Raghav, Kanwal Pratap; Girard, Lauren; Cheung, Sheree; Nguyen, Van; Ensor, Joe; Gadani, Sameer; Elsayes, Khaled M; Abdel-Wahab, Reham; Hassan, Manal; Shalaby, Ahmed S; Yao, James C; Wallace, Michael J; Kaseb, Ahmed O

    2016-01-01

    Purpose The safety and efficacy of the combined use of sorafenib and yttrium-90 resin microspheres (Y90 RMS) to treat advanced hepatocellular carcinoma (HCC) is not well established. We determined the incidence of adverse events with this combination therapy in patients with advanced HCC at our institution and analyzed the treatment and survival outcomes. Materials and methods We reviewed the records of 19 patients with Barcelona Clinic Liver Cancer class B or C HCC who underwent treatment with Y90 RMS (for 21 sessions) while receiving full or reduced doses of sorafenib between January 2008 and May 2010. Therapy response was evaluated using Response Evaluation Criteria in Solid Tumors. We evaluated median overall survival (OS) and progression-free survival (PFS) as well as hepatic and extrahepatic disease PFS and incidence of adverse events. Results The median patient age was 67 years, and portal or hepatic venous invasion was present in eight patients (42%). Ten patients received reduced doses of sorafenib. The median Y90 radiation activity delivered was 41.2 mCi. The partial response of Response Evaluation Criteria in Solid Tumors was observed in four patients (19%). The median hepatic disease PFS was 7.82 months, extrahepatic disease PFS was 8.94 months, OS was 19.52 months, and PFS was 6.63 months. Ninety days after treatment with Y90 RMS, five patients (26%) had grade II adverse events and four patients (21%) had grade III adverse events. Conclusion OS and PFS outcomes were superior to those observed in prior studies evaluating sorafenib alone in patients with a similar disease status, warranting further study of this treatment combination. PMID:27574586

  16. Spectrofluorimetric quantification of bilirubin using yttrium-norfloxacin complex as a fluorescence probe in serum samples

    Energy Technology Data Exchange (ETDEWEB)

    Kamruzzaman, Mohammad; Alam, Al-Mahmnur [Department of Chemistry, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Hak Lee, Sang, E-mail: shlee@knu.ac.kr [Department of Chemistry, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Ho Kim, Young, E-mail: youngkim@knu.ac.kr [Research Institute of Advanced Energy Technology, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Kim, Gyu-Man [School of Mechanical Engineering, Kyungpook National University, Daegu 702-701 (Korea, Republic of); Hyub Oh, Sang [Center for Gas Analysis, Korea Research Institute of Standards and Science, Daejeon 305-600 (Korea, Republic of)

    2012-11-15

    A simple and sensitive spectrofluorimetric method was developed to determine trace amounts of bilirubin (BR) using yttrium (Y{sup 3+})-norfloxacin (NFLX) complex as a fluorescence (FL) probe. NFLX can form a stable binary complex with Y{sup 3+} and markedly enhances the weak FL signal of the NFLX. The FL intensity of the Y{sup 3+}-NFLX complex decreased significantly in the presence of BR in a buffer solution at pH=7.2. Under optimal conditions, the FL intensity decreased according to the BR concentration and showed a good linear relationship in the range of 0.03-2.3 {mu}g mL{sup -1} of BR with a correlation coefficient of 0.9988. The limit of detection for the determination of BR was 2.8 ng mL{sup -1} with a relative standard deviation (RSD) of 1.55% for five replicate determination of 0.05 {mu}g mL{sup -1} BR. The presented method offers higher sensitivity with simple instrumentation and was applied successfully in detecting BR at low concentrations. Highlights: Black-Right-Pointing-Pointer Weak FL signal of NFLX was enhanced at 419 nm by forming binary complex with Y{sup 3+}. Black-Right-Pointing-Pointer The FL intensity of Y{sup 3+}-NFLX complex was quenched markedly in the presence of ATP. Black-Right-Pointing-Pointer NFLX can transfer energy to Y{sup 3+} and BR and form the Y{sup 3+}-NFLX-ATP ternary complex. Black-Right-Pointing-Pointer The reduced FL intensity of the system was correlated with the concentration of BR. Black-Right-Pointing-Pointer The method is applied to determine BR at low concentration (2.8 ng mL{sup -1}) in serum.

  17. Biodistribution of Yttrium-90-Labeled Anti-CD45 Antibody in a Nonhuman Primate Model

    Energy Technology Data Exchange (ETDEWEB)

    Nemecek, Eneida; Hamlin, Donald K.; Fisher, Darrell R.; Krohn, Kenneth A.; Pagel, John M.; Applebaum, F. R.; Press, Oliver W.; Matthews, Dana C.

    2005-01-15

    Radioimmunotherapy may improve the outcome of hematopoietic cell transplantation for hematologic malignancies by delivering targeted radiation to hematopoietic organs while relatively sparing nontarget organs. We evaluated the organ localization of yttrium-90-labeled anti-CD45 (90Y-anti-CD45) antibody in macaques, a model that had previously predicted iodine-131-labeled anti-CD-45 (131I-anti-CD45) antibody biodistribution in humans. Experimental Design: Twelve Macaca nemestrina primates received anti-CD45 antibody labeled with 1 to 2 mCi of 90Y followed by serial blood sampling and marrow and lymph node biopsies, and necropsy. The content of 90Y per gram of tissue was determined by liquid scintillation spectrometry. Time-activity curves were constructed using average isotope concentrations in each tissue at measured time points to yield the fractional residence time and estimate radiation absorbed doses for each organ per unit of administered activity. The biodistribution of 90Y-anti-CD45 antibody was then compared with that previously obtained with 131I-anti-CD45 antibody in macaques. Results: The spleen received 2,120, marrow 1,060, and lymph nodes 315 cGy/mCi of 90Y injected. The liver and lungs were the nontarget organs receiving the highest radiation absorbed doses (440 and 285 cGy/mCi, respectively). Ytrrium-90-labeled anti-CD45 antibody delivered 2.5- and 3.7-fold more radiation to marrow than to liver and lungs, respectively. The ratios previously observed with 131I-antiCD45 antibody were 2.5-and 2.2-fold more radiation to marrow than to liver and lungs, respectively. Conclusions: This study shows that 90Y-anti-CD45 antibody can deliver relatively selective radiation to hematopoietic tissues, with similar ratios of radiation delivered to target versus nontarget organs, as compared with the 131I immunoconjugate in the same animal model.

  18. Swift heavy ion-beam induced amorphization and recrystallization of yttrium iron garnet.

    Science.gov (United States)

    Costantini, Jean-Marc; Miro, Sandrine; Beuneu, François; Toulemonde, Marcel

    2015-12-16

    Pure and (Ca and Si)-substituted yttrium iron garnet (Y3Fe5O12 or YIG) epitaxial layers and amorphous films on gadolinium gallium garnet (Gd3Ga5O12, or GGG) single crystal substrates were irradiated by 50 MeV (32)Si and 50 MeV (or 60 MeV) (63)Cu ions for electronic stopping powers larger than the threshold value (~4 MeV μm(-1)) for amorphous track formation in YIG crystals. Conductivity data of crystalline samples in a broad ion fluence range (10(11)-10(16) cm(-2)) are modeled with a set of rate equations corresponding to the amorphization and recrystallization induced in ion tracks by electronic excitations. The data for amorphous layers confirm that a recrystallization process takes place above ~10(14) cm(-2). Cross sections for both processes deduced from this analysis are discussed in comparison to previous determinations with reference to the inelastic thermal-spike model of track formation. Micro-Raman spectroscopy was also used to follow the related structural modifications. Raman spectra show the progressive vanishing and randomization of crystal phonon modes in relation to the ion-induced damage. For crystalline samples irradiated at high fluences (⩾10(14) cm(-2)), only two prominent broad bands remain like for amorphous films, thereby reflecting the phonon density of states of the disordered solid, regardless of samples and irradiation conditions. The main band peaked at ~660 cm(-1) is assigned to vibration modes of randomized bonds in tetrahedral (FeO4) units.

  19. Yttrium-90 Radioembolization for Unresectable Standard-chemorefractory Intrahepatic Cholangiocarcinoma: Survival, Efficacy, and Safety Study

    Energy Technology Data Exchange (ETDEWEB)

    Rafi, Shoaib; Piduru, Sarat M. [Emory University School of Medicine, Division of Interventional Radiology and Image Guided Medicine, Department of Radiology (United States); El-Rayes, Bassel; Kauh, John S. [Emory University School of Medicine, Department of Hematology and Medical Oncology (United States); Kooby, David A.; Sarmiento, Juan M. [Emory University School of Medicine, Department of Surgical Oncology in Surgery (United States); Kim, Hyun S., E-mail: kevin.kim@emory.edu [Emory University School of Medicine, Division of Interventional Radiology and Image Guided Medicine, Department of Radiology (United States)

    2013-04-15

    To assess the overall survival, efficacy, and safety of radioembolization with yttrium-90 (Y90) for unresectable standard-chemorefractory intrahepatic cholangiocarcinoma (ICC). Patients with unresectable standard-chemorefractory ICC treated with Y90 were studied. Survival was calculated from the date of first Y90 procedure. Tumor response was assessed with the Response Evaluation Criteria in Solid Tumors criteria on follow-up computed tomography or magnetic resonance imaging scans. National Cancer Institute Common Terminology Criteria (NCI CTCAE), version 3, were used for complications. Statistical analysis was performed by the Kaplan-Meier estimator by the log rank test. Nineteen patients underwent a total of 24 resin-based Y90 treatments. Median survival from the time of diagnosis and first Y90 procedure was 752 {+-} 193 [95 % confidence interval (CI) 374-1130] and 345 {+-} 128 (95 % CI 95-595) days, respectively. Median survival with Eastern Cooperative Oncology Group (ECOG) performance status 1 (n = 15) and ECOG performance status 2 (n = 4) was 450 {+-} 190 (95 % CI 78-822) and 345 {+-} 227 (95 % CI 0-790) days, respectively (p = .214). Patients with extrahepatic metastasis (n = 11) had a median survival of 404 {+-} 309 (95 % CI 0-1010) days versus 345 {+-} 117 (95 % CI 115-575) days for patients without metastasis (n = 8) (p = .491). No mortality was reported within 30 days from first Y90 radioembolization. One patient developed grade 3 thrombocytopenia as assessed by NCI CTCAE. Fatigue and transient abdominal pain were observed in 4 (21 %) and 6 (32 %) patients, respectively. Y90 radioembolization is effective for unresectable standard-chemorefractory ICC.

  20. Shanxi Zhaofeng Aluminum Industry is Planning Oversea Listing

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    <正>Shanxi Yangquan Coal Industry(Group)Co., Ltd.intends to promote its subsidiary company Shanxi Zhaofeng Aluminum Metallurgy Co Ltd (hereinafter referred to as Zhaofeng Aluminum Metallurgy)to seek oversea listing.If its effort succeeds,Zhaofeng Aluminum Metallurgy will become the third public listed company under Yangquan Group.

  1. 21 CFR 582.1781 - Sodium aluminum phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sodium aluminum phosphate. 582.1781 Section 582.1781 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Additives § 582.1781 Sodium aluminum phosphate. (a) Product. Sodium aluminum phosphate. (b) Conditions...

  2. 21 CFR 182.1781 - Sodium aluminum phosphate.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Sodium aluminum phosphate. 182.1781 Section 182.1781 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... Food Substances § 182.1781 Sodium aluminum phosphate. (a) Product. Sodium aluminum phosphate....

  3. [Science and Technology and Recycling: Instructional Materials on Aluminum.

    Science.gov (United States)

    Aluminum Association, New York, NY.

    Educational materials on the manufacture and use of aluminum are assembled in this multi-media unit for use by junior high and secondary school students. Student booklets and brochures include: "The Story of Aluminum,""Uses of Aluminum,""Independent Study Guide for School Research Projects,""Questions and Answers About Litter, Solid Waste, and…

  4. 2009 China’s Aluminum Fabrication Industrial Development Report

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    <正>1 Overview of Aluminum Fabrication Industry Despite the impact of 2008’s financial crisis on China’s aluminum fabrication industry, China’s output of aluminum products remained the world’s largest in 2009, against overall steady

  5. New Tax Rebate Policy Favorable to Aluminum Processing Industry

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    <正>China has made the decision to increase export tax rebate rate for part of the non-ferrous products from April 1, 2009, among which the export tax rebate for aluminum alloy hollow profiles and other aluminum alloy profiles goes up to 13%. The new policy is a piece of good news for aluminum processing

  6. 21 CFR 73.1015 - Chromium-cobalt-aluminum oxide.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Chromium-cobalt-aluminum oxide. 73.1015 Section 73... LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1015 Chromium-cobalt-aluminum oxide. (a) Identity. The color additive chromium-cobalt-aluminum oxide is a blue-green pigment obtained by calcining...

  7. Shanxi Will Build Aluminum Deep Processing Industrial Park

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    As a province with high coal output,Shanx boasts rich electrolytic aluminum resources.On January 7,the reporter learned from the Provincial Commission of Economy and Information Technology that in order to continually expand the size of aluminum industry,extend aluminum industrial chain,so

  8. Status Quo of China’s Aluminum Sheet & Strip Industry

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    <正>Aluminum sheet & strip products are one of the major product varieties in the aluminum processing industry, they also provide indis-pensable basic materials for the development of national economy. In recent years, driven by rapid economic growth, China’s investment in aluminum sheet & strip industry continued to

  9. Pregnancies in women with hyperprolactinaemia: clinical course and obstetric complications of 41 pregnancies in 27 women. [Yttrium 90

    Energy Technology Data Exchange (ETDEWEB)

    Kelly, W.F.; Doyle, F.H.; Mashiter, K.; Banks, L.M.; Gordon, H.; Joplin, G.F.

    1979-09-01

    Observations are reported on 41 pregnancies in 27 patients who initially had infertility and raised serum prolactin concentrations. Associated symptoms were secondary amenorrhoea and galactorrhoea. All patients were at risk of pituitary expansion during pregnancy, especially these 19 (70 per cent) with radiological evidence of pituitary tumors. Fifteen patients had 21 pregnancies after pituitary implantation with 90 yttrium; 14 patients had 20 pegnancies without prior pituitary implantation or any other attempt to prevent tumor expansion. The induction and Cesarean section rates were about 30 per cent in 32 term pregnancies in 25 patients. Details of how pregnancy was achieved and the associated obstetric problems are given.

  10. Dielectric relaxation in double potassium yttrium orthophosphate K 3Y(PO 4) 2 doped by praseodymium and dysprosium ions

    Science.gov (United States)

    Szulia, S.; Kosmowska, M.; Kołodziej, H. A.; Mizer, D.; Czupińska, G.

    2011-12-01

    We report the paper presents the results of electric properties of double potassium yttrium orthophosphates doped by lanthanide ions K 3Y( 1-x)Ln x(PO 4) 2 ( x = 0.01, 0.05, Ln = Pr 3+, Dy 3+). Electric permittivity and dielectric loss measurements have been performed on polycrystalline samples in the temperature range -50-120 °C and frequency range 1 kHz-1 MHz by means of HP 4282A impedance meter. The frequency and temperature dependence of electric properties were analyzed by theoretical models of dielectric relaxation in order to obtain information abut molecular dynamic of our solids in external electric field.

  11. Laser MBE-grown yttrium iron garnet films on GaN: characterization of the crystal structure and magnetic properties

    Science.gov (United States)

    Kaveev, A. K.; Bursian, V. E.; Gastev, S. V.; Krichevtsov, B. B.; Suturin, S. M.; Volkov, M. P.; Sokolov, N. S.

    2016-07-01

    Yttrium iron garnet (YIG) films were grown on GaN substrates using the laser molecular beam epitaxy method. X-ray diffraction data showed polycrystalline YIG layers without additional structural modifications. The magnetic properties of the YIG films were studied at room temperature with the aid of a vibration sample magnetometer, the magneto-optical Kerr effect and ferromagnetic resonance methods. ‘Easy-plane’-type magnetic anisotropy was found in the films. The gyromagnetic ratio and 4 πMS value were calculated.

  12. Spectrographic determination of strontium in yttrium-90 solutions; Determinacion espectrografica de estroncio en soluciones de itrio-90

    Energy Technology Data Exchange (ETDEWEB)

    Roca, M.; Capdevila, C.

    1970-07-01

    The copper spark method has been used for determining strontium in the concentration range 1-100 g/ml in yttrium-90 solutions containing 0,5 % or thereabouts of ammonium citrate. The influence of the citric acid as well as the ammonium citrate with regard to 2N HCL solutions has been studied: the citric acid enhances the line intensities of strontium. The employment of either barium or lanthanum as reference element compensates for this enhancement. Because of the increase in sensitivity mentioned above, the study of influence of the citric acid has been extended and several impurities usually determined in radioisotope solutions have been considered. (Author) 4 refs.

  13. Analysis of inner filter effect on the up-conversion spectra of erbium doped yttrium oxide close-packed powders

    Science.gov (United States)

    Rakov, Nikifor; Maciel, Glauco S.

    2012-11-01

    We observed that the up-conversion (UC) emission profiles of erbium (Er3+) doped yttrium oxide (Y2O3) close-packed powders prepared by combustion synthesis are different when the luminescence reflected from the sample is compared to the luminescence transmitted through the sample (thickness: ˜0.1 mm). The effect was identified as a combination of scattering and an inner filter effect (IFE). The IFE reduces the transmitted UC luminescence bandwidths up to 50%. The IFE was suppressed by the inclusion of free-standing undoped Y2O3 particles.

  14. Spin Seebeck effect and spin Hall magnetoresistance at high temperatures for a Pt/yttrium iron garnet hybrid structure

    Science.gov (United States)

    Wang, Shuanhu; Zou, Lvkuan; Zhang, Xu; Cai, Jianwang; Wang, Shufang; Shen, Baogen; Sun, Jirong

    2015-10-01

    Based on unique experimental setups, the temperature dependences of the longitudinal spin Seebeck effect (LSSE) and spin Hall magnetoresistance (SMR) of the Pt/yttrium iron garnet (Pt/YIG) hybrid structure are determined in a wide temperature range up to the Curie temperature of YIG. From a theoretical analysis of the experimental relationship between the SMR and temperature, the spin mixing conductance of the Pt/YIG interface is deduced as a function of temperature. Adopting the deduced spin mixing conductance, the temperature dependence of the LSSE is well reproduced based on the magnon spin current theory. Our research sheds new light on the controversy about the theoretical models for the LSSE.

  15. Observation of two-dimensional yttrium oxide nanoparticles in mealworm beetles (Tenebrio molitor).

    Science.gov (United States)

    Chen, Yunyun; Sanchez, Carlos; Yue, Yuan; González, Jorge M; Parkinson, Dilworth Y; Liang, Hong

    2016-09-01

    Nanomaterials are being used in medicine, manufacturing and consumer products, but their effects on organisms and the environment are not well understood because of the difficulty in detecting them. Here dual-energy X-ray K-edge subtraction was used to track two-dimensional yttrium oxide nanoparticles (which can be found in such household objects as color televisions) in adult mealworms (Tenebrio molitor). The insects ingested nanoparticle-infused feed for different time periods, up to 24 h, and the nanoparticles could then be identified at several locations in the insects' head, thorax and abdomen, mostly within the digestive tract. In time, all particles were excreted.

  16. Controlled preparation of aluminum borate powders for the development of defect-related phosphors for warm white LED lighting

    Science.gov (United States)

    Guimarães, Vinicius F.; Salaün, Mathieu; Burner, Pauline; Maia, Lauro J. Q.; Ferrier, Alban; Viana, Bruno; Gautier-Luneau, Isabelle; Ibanez, Alain

    2017-03-01

    The optimization of the elaboration conditions of a new family of highly emissive white phosphors based on glassy yttrium aluminum borates (g-YAB) compositions is presented. Their preparation from solutions is based on the polymeric precursor method (modified Pechini process), involving non-toxic and low cost precursors. The resulting resins were first dried at moderate temperatures followed by two-step annealing treatments of the obtain powders under controlled atmospheres: a first pyrolysis under nitrogen followed by a calcination under oxygen. This favored the gradual oxidation of organic moieties coming from starting materials, avoiding uncontrolled self-combustion reactions, which generate localized hot spots. This prevented phase segregations and the formation of pyrolytic carbon or carbonates, which are strongly detrimental to the luminescence properties. Thus, coupled chemical analyses and luminescence characterizations showed the high chemical homogeneity of the resulting powders and their intense emissions in the whole visible range. These emissions can be tuned from blue to warm white by adjusting the calcination temperature that is an important advantage for the development of LED devices. We showed that impurities of monovalent and divalent cations act as quenching emission centers for these phosphors. Therefore, by increasing the purity grade, we significantly enhanced the PL emissions leading to high internal quantum yields (80-90%). Finally, cathodoluminescence emissions showed the homogeneous dispersion of emitting centers in the g-YAB matrix.

  17. Loften Aluminum Aluminum Foil Output to Reach 120,000 Tons in 2012

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    <正>Loften Aluminum Co., Ltd. was founded in 2000 Boxing County, Shandong Province. On 31 March 2010, Loften became an A-share listed company, creating favorable conditions for raising funds to expand its operations.

  18. CPI Challenges CHINALCO in Aluminum Business

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>China Power Investment Corporation (hereinafter referred to as CPI),one of the top 5 power generation groups,grows rapidly in aluminum business,making CHINALCO (hereinafter re-ferred to as CHINALCO),the traditional No.1

  19. Inelastic Deformation Analysis of Aluminum Bending Members

    Institute of Scientific and Technical Information of China (English)

    CHENG Ming; SHI Yongjiu; WANG Yuanqing

    2006-01-01

    Aluminum alloys are typical nonlinear materials, and consequently bending members made of this material exhibit a nonlinear behavior. Most design codes do not pay much attention to such deformations and adopt a simple linear analysis for the calculation of deflections. This paper presents an investigation of the nonlinear deformation of aluminum bending members using the finite-element analysis (FEA). The plastic adaptation coefficient, which can be used to limit the residual deflection, is introduced, and the influence of residual deflection is investigated. A method for evaluating the plastic adoption coefficient is proposed. This paper also shows the load-deflection curve of aluminum bending members and the influence of several parameters. A semi-empirical formula is derived, and some numerical examples are given by FEA. The coefficients of the semi-empirical formula are modified by the FEA results using the nonlinear fitting method. Based on these results, two improved design methods for strength and deformation of aluminum bending members are proposed. Through the comparison with test data, these methods are proved to be suitable for structural design.

  20. 75 FR 80527 - Aluminum Extrusions From China

    Science.gov (United States)

    2010-12-22

    ... Republic of China: Postponement of Final Determination of Sales at Less Than Fair Value, 75 FR 73041... Sales at Less Than Fair Value, and Preliminary Determination of Targeted Dumping, 75 FR 69403, November... Affirmative Countervailing Duty Determination, 75 FR 54302, September 7, 2010, and Aluminum Extrusions...

  1. Absorptive coating for aluminum solar panels

    Science.gov (United States)

    Desmet, D.; Jason, A.; Parr, A.

    1979-01-01

    Method for coating forming coating of copper oxide from copper component of sheet aluminum/copper alloy provides strong durable solar heat collector panels. Copper oxide coating has solar absorption characteristics similar to black chrome and is much simpler and less costly to produce.

  2. Molybdate Coatings for Protecting Aluminum Against Corrosion

    Science.gov (United States)

    Calle, Luz Marina; MacDowell, Louis G.

    2005-01-01

    Conversion coatings that comprise mixtures of molybdates and several additives have been subjected to a variety of tests to evaluate their effectiveness in protecting aluminum and alloys of aluminum against corrosion. Molybdate conversion coatings are under consideration as replacements for chromate conversion coatings, which have been used for more than 70 years. The chromate coatings are highly effective in protecting aluminum and its alloys against corrosion but are also toxic and carcinogenic. Hexavalent molybdenum and, hence, molybdates containing hexavalent molybdenum, have received attention recently as replacements for chromates because molybdates mimic chromates in a variety of applications but exhibit significantly lower toxicity. The tests were performed on six proprietary formulations of molybdate conversion coatings, denoted formulations A through F, on panels of aluminum alloy 2024-T3. A bare alloy panel was also included in the tests. The tests included electrochemical impedance spectroscopy (EIS), measurements of corrosion potentials, scanning electron microscopy (SEM) with energy-dispersive spectroscopy (EDS), and x-ray photoelectron spectroscopy (XPS).

  3. High Energy Density aluminum/oxygen cell

    Science.gov (United States)

    Rudd, E. J.; Gibbons, D. W.

    An alternative to a secondary battery as the power source for vehicle propulsion is a fuel cell, an example of which is the metal/air cell using metals such as aluminum, zinc, or iron. Aluminum is a particularly attractive candidate, with high energy and power densities, environmentally acceptable and having a large, established industrial base for production and distribution. An aluminum/oxygen system is currently under development for a prototype unmanned, undersea vehicle (UUV) for the US navy and recent work has focussed upon low corrosion aluminum alloys, and an electrolyte management system for processing the by-products of the energy-producing reactions. This paper summarizes the progress made in both areas. Anode materials capable of providing high utilization factors over current densities ranging from 5 to 150 mA/cm 2 have been identified, such materials being essential to realize mission life for the UUV. With respect to the electrolyte management system, a filter/precipitator unit has been successfully operated for over 250 h in a large scale, half-cell system.

  4. Friction Stir Welding of Aluminum Alloys

    Institute of Scientific and Technical Information of China (English)

    FU Zhi-hong; HE Di-qiu; WANG Hong

    2004-01-01

    Friction stir welding(FSW), a new solid-state welding technology invited in the early 1990s,enables us weld aluminum alloys and titanium alloys etc. The processing of FSW, the microstructure in FSW alloysand the factors influencing weld quality are introduced. The complex factors affecting the properties are researched.

  5. Laser micro welding of copper and aluminum

    Science.gov (United States)

    Mys, Ihor; Schmidt, Michael

    2006-02-01

    Aluminum combines comparably good thermal and electrical properties with a low price and a low material weight. These properties make aluminum a promising alternative to copper for a large number of electronic applications, especially when manufacturing high volume components. However, a main obstacle for a wide use of this material is the lack of a reliable joining process for the interconnection of copper and aluminum. The reasons for this are a large misalignment in the physical properties and even more a poor metallurgical affinity of both materials that cause high crack sensitivity and the formation of brittle intermetallic phases during fusion welding. This paper presents investigations on laser micro welding of copper and aluminum with the objective to eliminate brittle intermetallic phases in the welding structure. For these purposes a combination of spot welding, a proper beam offset and special filler material are applied. The effect of silver, nickel and tin filler materials in the form of thin foils and coatings in a thickness range 3-100 μm has been investigated. Use of silver and tin filler materials yields to a considerable improvement of the static and dynamic mechanical stability of welded joints. The analysis of the weld microstructure shows that an application even of small amounts of suitable filler materials helps to avoid critical, very brittle intermetallic phases on the interface between copper and solidified melt in the welded joints.

  6. UV fluorescence enhancement from nanostructured aluminum materials

    Science.gov (United States)

    Montanari, Danielle E.; Dean, Nathan; Poston, Pete E.; Blair, Steve; Harris, Joel M.

    2016-09-01

    Interest in label-free detection of biomolecules has given rise to the need for UV plasmonic materials. DNA bases and amino acid residues have electronic resonances in the UV which allow for sensitive detection of these species by surface-enhanced UV fluorescence spectroscopy. Electrochemical roughening has been used extensively to generate plasmonically-active metal surfaces that produce localized enhancement of excitation and emission of electromagnetic radiation from surface-bound molecules. Electrochemically roughened gold and silver surfaces produce enhancement in the visible and near-IR regions, but to the best of our knowledge, application of this technique for producing UV-enhancing substrates has not been reported. Using electropolishing of aluminum, we are able to generate nanostructured surfaces that produce enhanced spectroscopic detection of molecules in the UV. Aluminum is a natural choice for substrate composition as it exhibits a relatively large quality factor in the UV. We have fabricated electropolished aluminum films with nanometer scale roughness and have studied UV-excited fluorescence enhancement from submonolayer coverage of tryptophan on these substrates using a UV-laser based spectrometer. Quantitative dosing by dip-coating was used to deposit known surface concentrations of the aromatic amino acid tryptophan, so that fluorescence enhancement could be evaluated. Compared to a dielectric substrate (surface-oxidized silicon), we observe a 180-fold enhancement in the total fluorescence emitted by tryptophan on electropolished aluminum under photobleaching conditions, allowing detection of sub-monolayer coverages of molecules essential for development of biosensor technologies.

  7. Low absorptance porcelain-on-aluminum coating

    Science.gov (United States)

    Leggett, H.

    1979-01-01

    Porcelain thermal-control coating for aluminum sheet and foil has solar absorptance of 0.22. Specially formulated coating absorptance is highly stable, changing only 0.03 after 1,000 hours of exposure to simulated sunlight and can be applied by standard commercial methods.

  8. Optical properties of ALON (aluminum oxynitride)

    Science.gov (United States)

    Hartnett, T. M.; Bernstein, S. D.; Maguire, E. A.; Tustison, R. W.

    1998-06-01

    The optical properties of ALON (aluminum oxynitride) are presented. Optical scatter and index of refraction, and absorption of several different compositions of ALON are compared. The temperature dependence of emissivity of ALON was measured in the temperature range 46°C to 1200°C.

  9. Aluminum Foil and Aluminum Sheet Project with the Total Investment of RMB 1 billion Officially Launched in Wanshan

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    <正>According the news report on February 25,Wanshan district and Galaxy Aluminum Co.,Ltd. in Shengzhou,Zhejiang province signed an agreement on aluminum foil and aluminum sheet production on February 19 in Sanya,Hainan province,a sign that the project is offi- cially established in Wanshan.

  10. Hangzhou Jinjiang Group Shanxi Fusheng Aluminum Phase I 800,000 t/a Aluminum Oxide Project Started Operation

    Institute of Scientific and Technical Information of China (English)

    2014-01-01

    <正>On October 19,the Shanxi Province Pinglu County Phase I 800,000t/a Aluminum Oxide Project of Shanxi Fusheng Aluminum Co.,Ltd,a subordinate of Hangzhou Jinjiang Group,started operation.This is the fourth Aluminum oxide project constructed and operated by Jinjiang Group.

  11. Investigation of Methods for Selectively Reinforcing Aluminum and Aluminum-Lithium Materials

    Science.gov (United States)

    Bird, R. Keith; Alexa, Joel A.; Messick, Peter L.; Domack, Marcia S.; Wagner, John A.

    2013-01-01

    Several studies have indicated that selective reinforcement offers the potential to significantly improve the performance of metallic structures for aerospace applications. Applying high-strength, high-stiffness fibers to the high-stress regions of aluminum-based structures can increase the structural load-carrying capability and inhibit fatigue crack initiation and growth. This paper discusses an investigation into potential methods for applying reinforcing fibers onto the surface of aluminum and aluminum-lithium plate. Commercially-available alumina-fiber reinforced aluminum alloy tapes were used as the reinforcing material. Vacuum hot pressing was used to bond the reinforcing tape to aluminum alloy 2219 and aluminum-lithium alloy 2195 base plates. Static and cyclic three-point bend testing and metallurgical analysis were used to evaluate the enhancement of mechanical performance and the integrity of the bond between the tape and the base plate. The tests demonstrated an increase in specific bending stiffness. In addition, no issues with debonding of the reinforcing tape from the base plate during bend testing were observed. The increase in specific stiffness indicates that selectively-reinforced structures could be designed with the same performance capabilities as a conventional unreinforced structure but with lower mass.

  12. Removal of Aluminum from Water and Industrial Waste Water

    Directory of Open Access Journals (Sweden)

    Parisa Ghashghaiee pour

    2014-09-01

    Full Text Available This study attempts to introduce a procedure to remove Aluminum ions from drinking water and industrial effluents by using active carbon with different grading as absorbent. Absorption of Aluminum ions were discussed in different conditions of Aluminum concentration, contact time, impact of electrolytes and pH on Aluminum ions absorbency. Both Freundlich and Langmuir isotherms used to investigate the adsorption. Thermodynamics relations governing process, such as specification of ( , ( and the enthalpy of adsorption, were calculated, which showed that Aluminum absorption on active carbon is an endothermic and spontaneous process.

  13. Preparation of Ultra-fine Aluminum Nitride in Thermal Plasma

    Institute of Scientific and Technical Information of China (English)

    漆继红; 罗义文; 印永祥; 代晓雁

    2002-01-01

    Ultra-fine aluminum nitride has been synthesized by the evaporation of aluminum powder at atmospheric-pressure nitrogen plasma in a hot-wall reactor. The average size of aluminum nitride particle is 0.11μm measured by scanning electric mirror (SEM), and the purity is at least over 90% evaluated by X-Ray diffraction (XRD). The conversion of Al powder to aluminum nitride is strongly depended on the injection of NH3. Typical experimental parameters such as the feed rate of raw material, the flow rate of ammonia and the position of injecting aluminum powder into the reactor are given.

  14. Predicting the residual aluminum level in water treatment process

    OpenAIRE

    J. Tomperi; M. Pelo; K. Leiviskä

    2012-01-01

    In water treatment processes, aluminum salts are widely used as coagulation chemical. High dose of aluminum has been proved to be at least a minor health risk and some evidence points out that aluminum could increase the risk of Alzheimer's disease thus it is important to minimize the amount of residual aluminum in drinking water and water used at food industry. In this study, the data of a water treatment plant (WTP) was analyzed and the residual aluminum in drinking water was predicted usin...

  15. Predicting the residual aluminum level in water treatment process

    OpenAIRE

    J. Tomperi; M. Pelo; K. Leiviskä

    2013-01-01

    In water treatment processes, aluminum salts are widely used as coagulation chemical. High dose of aluminum has been proved to be at least a minor health risk and some evidence points out that aluminum could increase the risk of Alzheimer's disease. Thus it is important to minimize the amount of residual aluminum in drinking water and water used at food industry. In this study, the data of a water treatment plant (WTP) was analyzed and the residual aluminum in drinking water was predicted usi...

  16. Rheology of suspensions with aluminum nano-particles

    Directory of Open Access Journals (Sweden)

    Ulrich Teipel

    2009-01-01

    Full Text Available Nano-scale aluminum particles are innovative materials increasingly used in energetic formulations. In this contribution, the rheological behavior of suspensions with either paraffin oil or HTPB as the matrix fluid and nano-scale aluminum (ALEX as the dispersed phase is described and discussed. The paraffin oil/aluminum suspensions exhibit non-Newtonian flow behavior over a wide range of concentrations, whereas the HTPB/aluminum suspensions exhibitNewtonian behavior (i.e. the viscosity is independent of shear stress up to a concentration of 50 vol.% aluminum. Both systems have unusual viscoelastic properties in that their elastic moduli are independent of the solids concentration.

  17. Aluminum Target Dissolution in Support of the Pu-238 Program

    Energy Technology Data Exchange (ETDEWEB)

    McFarlane, Joanna [ORNL; Benker, Dennis [ORNL; DePaoli, David W [ORNL; Felker, Leslie Kevin [ORNL; Mattus, Catherine H [ORNL

    2014-09-01

    Selection of an aluminum alloy for target cladding affects post-irradiation target dissolution and separations. Recent tests with aluminum alloy 6061 yielded greater than expected precipitation in the caustic dissolution step, forming up to 10 wt.% solids of aluminum hydroxides and aluminosilicates. We present a study to maximize dissolution of aluminum metal alloy, along with silicon, magnesium, and copper impurities, through control of temperature, the rate of reagent addition, and incubation time. Aluminum phase transformations have been identified as a function of time and temperature, using X-ray diffraction. Solutions have been analyzed using wet chemical methods and X-ray fluorescence. These data have been compared with published calculations of aluminum phase diagrams. Temperature logging during the transients has been investigated as a means to generate kinetic and mass transport data on the dissolution process. Approaches are given to enhance the dissolution of aluminum and aluminosilicate phases in caustic solution.

  18. CATALOG INFORMATION ON THE PERFORMANCE OF ALUMINUM IN SEA WATER

    Energy Technology Data Exchange (ETDEWEB)

    RH. Wagner and RA. Bonewitz

    1978-04-01

    To help evaluate aluminum alloys for OTEC heat exchanger tubes data on the performance of aluminum in surface and deep sea water has been assembled and computer cataloged. Pitting and crevice corrosion proved to be the types of attack that predominated. The cataloged data are the results of many static tests conducted under natural conditions of marine fouling, hence, they must be used carefully in qualifying aluminum for OTEC purposes. These data can serve the OTEC program best as a basis for selecting aluminum alloys that appear promising as candidates for further evaluation. The aluminum alloys 5052 and Alclad {7072) 3003 fall into this category. Available service histories also proved inadequate for qualifying aluminum alloys for the OTEC application, but they do support the selection of Alclad (7072) 3003 as a tubing alloy worthy of further consideration. Performance data covering areas of investigation peculiar to OTEC power plants is needed to permit a firm decision for or against aluminum alloy tubes.

  19. Lobar Hepatocellular Carcinoma with Ipsilateral Portal Vein Tumor Thrombosis Treated with Yttrium-90 Glass Microsphere Radioembolization: Preliminary Results

    Directory of Open Access Journals (Sweden)

    M. Pracht

    2013-01-01

    Full Text Available Portal vein tumor thrombosis (PVTT is a common complication of hepatocellular carcinoma (HCC and has a negative impact on prognosis. This characteristic feature led to the rationale of the present trial designed to assess the efficacy and the safety of yttrium-90 glass-microsphere treatment for advanced-stage lobar HCC with ipsilateral PVTT. 18 patients with unresectable lobar HCC and ipsilateral PVTT were treated in our institution with 90Y-microS radioembolization. Patients were evaluated every 3 to 6 months for response, survival, and toxicity. Mean follow-up was 13.0 months (2.2–50.6. Outcomes were: complete response (n=2, partial response (n=13, stable disease (n=1, and progressive disease (n=2 giving a disease control rate of 88.9%. Four patients were downstaged. Treating lobar hepatocellular carcinoma with ipsilateral portal vein thrombosis with yttrium-90 glass-microsphere radioembolization is safe and efficacious. Further clinical trials are warranted to confirm these results and to compare 90Y-microS with sorafenib, taking into account not only survival but also the possibility of secondary surgery for putative curative intention after downstaging.

  20. Measurement of cross-sections of yttrium (n,xn) threshold reactions by means of gamma spectroscopy

    CERN Document Server

    Chudoba, Petr; Wagner, V; Vrzalova, J; Svoboda, O; Majerle, M; Stefanik, M; Suchopar, M; Kugler, A; Bielewicz, M; Strugalska-Gola, E; Szuta, M; Hervas, D; Herman, T; Geier, B

    2014-01-01

    Neutron activation and gamma spectrometry are usable also f or the determination of cross-sections of different neutron reactions. We have studied the cross-sections of yttrium (n, x n) threshold reactions using quasi-monoenergetic neutron source based on the reaction on 7 Li target at Nuclear Physics Institute of ASCR in Rez. Yttrium (n, x n) threshold reactions are suitable candidates for fast neutron field measurement by activation detectors. Fast neutron field monitoring is necessary already today at a wide range of accelerator facilities and will gain on importance in future fast reactors of generation IV, accelerator transmutation systems or fusion reactors. The knowledge of the cross-sections is crucial for such purpose. Unfortunately, the cross-section is sufficiently known only for 89 Y(n,2n) 88 Y reaction. For higher orders of reactions there are almost no experimental data. Special attention was paid to t he 89 Y(n,3n) 87 Y reaction. The cross-sections of both 89 Y(n,2n) 88 Y and 89 Y(n,3n) 87 Y re...

  1. Thickness and component distributions of yttrium-titanium alloy films in electron-beam physical vapor deposition

    Institute of Scientific and Technical Information of China (English)

    LI ShuaiHui; SHU YongHua; FAN Jing

    2008-01-01

    Thickness and component distributions of large-area thin films are an issue of in-ternational concern in the field of material processing. The present wor0k employs experiments and direct simulation Monte Carlo (DSMC) method to investigate three-dimensional low-density, non-equilibrium jets of yttrium and titanium vapor atoms in an electron-beams physical vapor deposition (EBPVD) system furnished with two or three electron-beams, and obtains their deposition thickness and component distributions onto 4-inch and 6-inch mono-crystal silicon wafers. The DSMC results are found in excellent agreement with our measurements, such as evaporation rates of yttrium and titanium measured in-situ by quartz crystal reso-nators, deposited film thickness distribution measured by Rutherford backscat-tering spectrometer (RBS) and surface profilometer and deposited film molar ratio distribution measured by RBS and inductively coupled plasma atomic emission spectrometer (ICP-AES). This can be taken as an indication that a combination of DSMC method with elaborate measurements may be satisfactory for predicting and designing accurately the transport process of EBPVD at the atomic level.

  2. Measurement of Cross-sections of Yttrium (n,xn) Threshold Reactions by Means of Gamma Spectroscopy

    Science.gov (United States)

    Chudoba, P.; Kilim, S.; Wagner, V.; Vrzalova, J.; Svoboda, O.; Majerle, M.; Stefanik, M.; Suchopar, M.; Kugler, A.; Bielewicz, M.; Strugalska-Gola, E.; Szuta, M.; Hervas, D.; Herman, T.; Geier, B.

    Neutron activation and gamma spectrometry are usable also for the determination of cross-sections of different neutron reactions. We have studied the cross-section of yttrium (n,xn) threshold reactions using quasi mono-energetic neutron source based on the reaction on 7Li target at Nuclear Physics Institute of ASCR in Rez. Yttrium (n,xn) threshold reactions are suitable candidates for fast neutron field measurement by activation detectors. Fast neutron field monitoring is necessary already today at a wide range of accelerator facilities and will gain on importance in future fast reactors of generation IV, accelerator transmutation systems or fusion reactors. The knowledge of the cross-sections is crucial for such purpose. Unfortunately, the cross-section is sufficiently known only for 89Y(n,2n)88Y reaction. For higher orders of reactions there are almost no experimental data. Special attention was paid to the 89Y(n,3n)87Y reaction. The nuclei are produced, both in the ground state with half-life 79.8 hours and in the isomeric state with half-life 13.38 hours. The isomer decays mainly through the gamma transition to the ground state, the beta decay of the excited state is negligible within our accuracy. The cross-sections of both 87Y productions were analyzed.

  3. Linear optical properties and their bond length dependence of yttrium bromide from ab initio and density functional theory calculations

    Energy Technology Data Exchange (ETDEWEB)

    Alipour, Mojtaba, E-mail: malipour@shirazu.ac.ir [Department of Chemistry, College of Sciences, Shiraz University, Shiraz 71454 (Iran, Islamic Republic of); Mohajeri, Afshan, E-mail: amohajeri@shirazu.ac.ir [Department of Chemistry, College of Sciences, Shiraz University, Shiraz 71454 (Iran, Islamic Republic of)

    2011-08-25

    Graphical abstract: The electronic properties such as the static dipole polarizability, anisotropy of the polarizability, and dipole moment of yttrium bromide, YBr (X{sup 1}{Sigma}) have been theoretically studied. Highlights: {yields} Conventional ab initio and density functional theory methods were employed to study linear optical properties of YBr molecule. {yields} Properties derivatives and their level of theory dependence were studied. {yields} Electron correlation effects and rovibrational corrections have also been discussed. - Abstract: We have employed conventional ab initio and density functional theory methods to study the electronic properties such as the mean static dipole polarizability, {alpha}-bar, anisotropy of the polarizability, {Delta}{alpha}, and dipole moment, {mu}, of yttrium bromide. The bond length dependence of properties is determined at different levels of theory and appropriate expansions around experimental internuclear distance have been presented. Moreover, the first and second geometrical derivatives for each property are quantified and their level of theory dependence has been analyzed. To study the effect of molecular rotation and vibration on the electronic properties, the rovibrational corrections have also been carried out. It is found that these corrections are less pronounced for considered properties of YBr. In all calculations, the electron correlation effects have been considered and discussed. The obtained results show that the electron correlation is more significant in the calculation of the mean and the anisotropy of dipole polarizability.

  4. Thickness and component distributions of yttrium-titanium alloy films in electron-beam physical vapor deposition

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Thickness and component distributions of large-area thin films are an issue of in-ternational concern in the field of material processing. The present work employs experiments and direct simulation Monte Carlo (DSMC) method to investigate three-dimensional low-density, non-equilibrium jets of yttrium and titanium vapor atoms in an electron-beams physical vapor deposition (EBPVD) system furnished with two or three electron-beams, and obtains their deposition thickness and component distributions onto 4-inch and 6-inch mono-crystal silicon wafers. The DSMC results are found in excellent agreement with our measurements, such as evaporation rates of yttrium and titanium measured in-situ by quartz crystal reso-nators, deposited film thickness distribution measured by Rutherford backscat-tering spectrometer (RBS) and surface profilometer and deposited film molar ratio distribution measured by RBS and inductively coupled plasma atomic emission spectrometer (ICP-AES). This can be taken as an indication that a combination of DSMC method with elaborate measurements may be satisfactory for predicting and designing accurately the transport process of EBPVD at the atomic level.

  5. Quantitative and qualitative assessment of Yttrium-90 PET/CT imaging.

    Directory of Open Access Journals (Sweden)

    Ali Asgar Attarwala

    Full Text Available Yttrium-90 is known to have a low positron emission decay of 32 ppm that may allow for personalized dosimetry of liver cancer therapy with (90Y labeled microspheres. The aim of this work was to image and quantify (90Y so that accurate predictions of the absorbed dose can be made. The measurements were performed within the QUEST study (University of Sydney, and Sirtex Medical, Australia. A NEMA IEC body phantom containing 6 fillable spheres (10-37 mm ∅ was used to measure the 90Y distribution with a Biograph mCT PET/CT (Siemens, Erlangen, Germany with time-of-flight (TOF acquisition. A sphere to background ratio of 8:1, with a total (90Y activity of 3 GBq was used. Measurements were performed for one week (0, 3, 5 and 7 d. he acquisition protocol consisted of 30 min-2 bed positions and 120 min-single bed position. Images were reconstructed with 3D ordered subset expectation maximization (OSEM and point spread function (PSF for iteration numbers of 1-12 with 21 (TOF and 24 (non-TOF subsets and CT based attenuation and scatter correction. Convergence of algorithms and activity recovery was assessed based on regions-of-interest (ROI analysis of the background (100 voxels, spheres (4 voxels and the central low density insert (25 voxels. For the largest sphere, the recovery coefficient (RC values for the 30 min -2-bed position, 30 min-single bed and 120 min-single bed were 1.12 ± 0.20, 1.14 ± 0.13, 0.97 ± 0.07 respectively. For the smaller diameter spheres, the PSF algorithm with TOF and single bed acquisition provided a comparatively better activity recovery. Quantification of Y-90 using Biograph mCT PET/CT is possible with a reasonable accuracy, the limitations being the size of the lesion and the activity concentration present. At this stage, based on our study, it seems advantageous to use different protocols depending on the size of the lesion.

  6. Effect of yttrium on photosynthesis and water relations in young maize plants

    Institute of Scientific and Technical Information of China (English)

    Ivana Maksimovi; Rudolf Kastori; Marina Putnik-Deli; Milan Boriev

    2014-01-01

    Despite an increase in spectrum of industrial applications of yttrium (Y) and the fact that it is widely present in the soils and plants, some of which are agronomically important crops, its effects on plant growth and metabolism are still obscure. Therefore, the aim of this work was to examine the effect of different concentrations of Y on its accumulation and distribution, photosynthetic responses, water relations, free proline concentration and growth of young maize plants. The experiment was done with maize (Zea mays L., hybrid NS-640), in water cultures, under semi-controlled conditions of a greenhouse. Plants were supplied with half-strength complete Hoagland nutrient solution, to which was added either 0 (control), 10-5, 10-4 or 10-3 mol/L Y, in the form of Y(NO)3·5H2O. Each variant was set in thirteen replications, with six plants in each replication. Plants were grown for 21 d and they were at the stage of 3 and 4 leaves when they were analyzed. The presence of Y reduced maize growth and photosynthetic performance. Dimensions of stomata significantly decreased while their density significantly increased on both adaxial and abaxial epidermis. Plant height, root length, total leaf area and dry mass also declined. Concentration of photosynthetic pigments (chl a and b and carotenoids) and free proline decreased. Photosynthesis and transpiration were impaired in the presence of Y-their intensities were also reduced, and the same stands for stomatal conductance of water vapor, photosynthetic water use efficiency (WUE) and water content. Although the highest concentration of Y was found in maize roots in each treatment, Y concentration in the second leaf and shoot also significantly increased with an increase in Y concentration in the nutrient solution. Albeit Y concentration was much higher in roots than in shoots, shoot metabolism and growth were much more disrupted. The results demonstrated that young maize plants accumulated significant amount of Y and that

  7. Robust Multifunctional Yttrium-Based Metal-Organic Frameworks with Breathing Effect.

    Science.gov (United States)

    Firmino, Ana D G; Mendes, Ricardo F; Antunes, Margarida M; Barbosa, Paula C; Vilela, Sérgio M F; Valente, Anabela A; Figueiredo, Filipe M L; Tomé, João P C; Paz, Filipe A Almeida

    2017-02-06

    Phosphonate- and yttrium-based metal-organic frameworks (MOFs), formulated as [Y(H5btp)]·5.5H2O (1), [Y(H5btp)]·2.5H2O (2), (H3O)[Y2(H5btp)(H4btp)]·H2O (3), and [Y(H5btp)]·H2O·0.5(MeOH) (4), were prepared using a "green" microwave-assisted synthesis methodology which promoted the self-assembly of the tetraphosphonic organic linker [1,1'-biphenyl]-3,3',5,5'-tetrayltetrakis(phosphonic acid) (H8btp) with Y(3+) cations. This new family of functional materials, isolated in bulk quantities, exhibits a remarkable breathing effect. Structural flexibility was thoroughly studied by means of X-ray crystallography, thermogravimetry, variable-temperature X-ray diffraction, and dehydration and rehydration processes, ultimately evidencing a remarkable reversible single-crystal to single-crystal (SC-SC) transformation solely through the loss and gain of crystallization solvent molecules. Topologically, frameworks remained unaltered throughout this interconversion mechanism, with all compounds being binodal 6,6-connected network with a Schäfli symbol of {4(13).6(2)}{4(8).6(6).8}. Results show that this is one of the most stable and thermally robust families of tetraphosphonate-based MOFs synthesized reported to date. Porous materials 2 and 3 were further studied to ascertain their performance as heterogeneous catalysts and proton conductors, respectively, with outstanding results being registered for both materials. Compound 2 showed a 94% conversion of benzaldehyde into (dimethoxymethyl)benzene after just 1 h of reaction, among the best results registered to date for MOF materials. On the other hand, the protonic conductivity of compound 3 at 98% of relative humidity (2.58 × 10(-2) S cm(-1)) was among the highest registered among MOFs, with the great advantage of the material to be prepared using a simpler and sustainable synthesis methodology, as well as exhibiting a good stability at ambient conditions (temperature and humidity) over time when compared to others.

  8. Bose–Einstein condensation and superfluidity of magnons in yttrium iron garnet films

    Science.gov (United States)

    Sun, Chen; Nattermann, Thomas; Pokrovsky, Valery L.

    2017-04-01

    A brief review of the theory of quasi-equilibrium Bose–Einstein condensation and superfluidity of magnons in a film of yttrium iron garnet is presented. The Bose–Einstein condensation of magnons in YIG film at room temperature under rf pumping was discovered in 2006 by the Münster experimental team led by Demokritov. There are two symmetric minima in the magnon spectrum of a ferromagnetic film, and therefore two condensates. In 2012 the same experimental group discovered the interference of these two condensates, thus proving their coherence. The reviewed theory that explains these experimental observations predicts that the reflection symmetry of the magnon gas is spontaneously violated at Bose–Einstein condensation in thick films. In thin films the condensate is symmetric at low magnetic field and transits to the non-symmetric state at higher field. Dipolar interaction energy depends on the phase of the condensate wave function. In quasi-equilibrium it traps the phase. All these features are due to the interaction between magnons Since the magnon condensate is coherent, a logical question is whether the condensate is superfluid. Two obstacles for superfluidity are the dominance of the normal magnon density over the condensate (approximately 100-fold) and the phase trapping. We show that the velocity of the superfluid part is by 5–7 decimal orders larger than that of the normal part at typical values of the field gradients. Thus, the spin current is mainly superfluid. The phase trapping violates the U(1) symmetry, reducing it to a discrete symmetry. Stationary superfluid flow is still possible, but it becomes inhomogeneous. In 1-d stationary flow at low kinetic energy the condensate phase over long intervals of length remains close to the trapped values and changes by 2π within comparatively short intervals (phase solitons). The current and number of magnons are conserved globally but not locally, since they transfer spin momentum to the lattice. These

  9. Thermal stability of platinum, palladium and silver films on yttrium-stabilised zirconia

    Energy Technology Data Exchange (ETDEWEB)

    Beck, Gesa, E-mail: gesa.beck@physik.uni-augsburg.de [Chair of Resource Strategy, Institute of Physics, University Augsburg, Universitaetsstrasse 1a, 86159 Augsburg (Germany); Bachmann, Christoph [Institute of Physical Chemistry, Justus-Liebig-University Giessen, Heinrich-Buff-Ring 58, 35392 Giessen (Germany); Bretzler, Rita [Research Institute Precious Metals and Metals Chemistry, Katharinenstrasse 17, 73525 Schwaebisch Gmuend (Germany); Kmeth, Ralf [Chair of Resource Strategy, Institute of Physics, University Augsburg, Universitaetsstrasse 1a, 86159 Augsburg (Germany)

    2014-12-31

    Platinum, palladium and silver films with different microstructures have been prepared on differently orientated yttrium-stabilised zirconia (YSZ) substrates by pulsed laser deposition and then annealed at temperatures between 200 °C and 850 °C. Thereby, an influence of the type of metal, of the microstructure of the as-prepared film and of the orientation of the substrate on the annealing behaviour could be determined. The following annealing effects were observed for platinum, palladium and silver films: i) sharpening of the film boundary, ii) smoothing of the film surfaces, iii) sharpening of the texture [thereby: reduction of the fraction of small angle and twin grain boundaries], iv) grain growth and accordingly reduction of the fraction of grains as well as v) grooving at grain boundaries, vi) void formation at the metal|YSZ-interface, vii) hole formation within the films and viii) reduction of the fraction of droplets. In the case of palladium films also ix) oxidation [between 300 °C ≤ T < 750 °C] and stronger de-wetting phenomena than for platinum [with x) waving of the film and xi) island formation at T ≥ 750 °C] have been found. Silver films are not oxidised, but show stronger de-wetting phenomena than platinum and palladium, with xi) island formation and xii) evaporation of the silver at T ≥ 550 °C. Interestingly, silver films on (111) orientated YSZ are thermally much more stable than silver films on the other orientated substrates up to 750 °C. The annealing effects were described by interface, grain boundary and surface energy minimization. - Highlights: • The thermal stability of Pt, Pd and Ag films has been investigated up to 850 °C. • Annealing effects are e.g. reduction of the fraction of twins and island formation. • Pd is also oxidised between 300 °C ≤ T < 750 °C. • Annealing effects depend on type of metal and on its initial microstructure. • Annealing effects depend also on the orientation of substrate.

  10. ALUMINUM CONTENT OF TEA LEAVES AND FACTORS AFFECTING THE UPTAKE OF ALUMINUM FROM SOIL INTO TEA LEAVES

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Numerous studies indicated that aluminum, the most abundant metallic element within the lithosphere, was considered to be related to some human diseases especially the Alzheimer's disease. Tea, economically an important beverage in the world, has been found to contain higher concentration of aluminum than many other drinks and foods. Therefore, tea would be a potentially important source of dietary aluminum. In order to understand the sources of aluminum in tea leaves and factors related with aluminum content of tea leaves, an experiment was designed to investigate the relationships of aluminum in tea leaves with leaf age, soil properties and forms of aluminum in soils. The results showed that there were great distinctions in the concentration of aluminum in tea leaves with different leaf age (Alold leaf> Almature leaf> Alyoung leaf). Moreover, soil pH was the major factor controlling the uptake of aluminum from soil into tea leaves. Furthermore, the content of aluminum in tea leaves was better predicated by the soluble aluminum extracted by 0. 02mol/L CaCl2.

  11. Activation of O2 and CH4 on yttrium-stabilized zircoma for the partial oxidation of methane to synthesis gas.

    NARCIS (Netherlands)

    Zhu, Jianjun; Ommen, van Jan G.; Bouwmeester, Henny J.M.; Lefferts, Leon

    2005-01-01

    The isotopic exchange reaction on ZrO2 and yttrium-stabilized ZrO2 (YSZ) during catalytic partial oxidation of methane to synthesis gas (CPOM) was studied with transient pulse experiments. The results reveal, surprisingly, that CPOM over both oxides proceeds via a Mars¿van Krevelen mechanism. Despit

  12. Platinum thickness dependence of the inverse spin-Hall voltage from spin pumping in a hybrid yttrium iron garnet/platinum system

    NARCIS (Netherlands)

    Castel, V.; Vlietstra, N.; Ben Youssef, J.; van Wees, B. J.

    2012-01-01

    We show the experimental observation of the platinum thickness dependence in a hybrid yttrium iron garnet/platinum system of the inverse spin-Hall effect from spin pumping, over a large frequency range and for different radio-frequency powers. From the measurement of the voltage at the resonant cond

  13. Influence of Yttrium Ion-implantation on Oxidation Kinetics of Co-40Cr Alloy and Property of Oxide/Substrate Interface

    Institute of Scientific and Technical Information of China (English)

    JIN Huiming; WU Dan; FELIX Congrado; AROYAVE Hayara

    2007-01-01

    The isothermal and cyclic oxidizing kinetics of Co-40Cr alloy and its yttrium ion-implanted samples were studied at 1000℃ in air by thermal-gravity analysis (TGA). Scanning electronic microscopy (SEM) was used to examine the Cr2O3 oxide film's morphology after oxidation. Secondary ion mass spectroscopy (SIMS) method was used to examine the binding energy change of chromium caused by yttrium doping. Acoustic emission (AE) method was used in situ to monitor the cracking and spalling of oxide films formed on both samples during oxidizing and subsequent air-cooling stages. It is found that yttrium implantation remarkably reduces the isothermal oxidizing rate of Co-40Cr and improves the anti-cracking and anti-spalling properties of Cr2O3 oxide film. The reasons for the improvements are mainly that implanted yttrium reduces the grain size of Cr2O3 oxide, increases the high temperature plasticity of oxide film, and remarkably reduces the number and size of Cr2O3/Co-40Cr interfacial defects.

  14. Synthesis, characterization, and activity of yttrium(III) nitrate complexes bearing tripodal phosphine oxide and mixed phosphine-phosphine oxide ligands.

    Science.gov (United States)

    Sues, Peter E; Lough, Alan J; Morris, Robert H

    2012-09-03

    A series of four tripodal phosphine oxide ligands, (OPR(2))(2)CHCH(2)POR(2) (1a-1d), and four mixed phosphine-phosphine oxide ligands, (OPR(2))(2)CHCH(2)PR(2) (3a-3d), were synthesized and coordinated to yttrium to produce Y(NO(3))(3)[(OPR(2))(2)CHCH(2)POR(2)] (2a-2d) and Y(NO(3))(3)[(OPR(2))(2)CHCH(2)PR(2)](OPPh(3)) (4a-4d) complexes. The previously reported ligand 1a and unknown phosphine oxide ligands 1b-1d were generated in an unprecedented trisubstitution reaction of bromoacetaldehyde diethyl acetal, while the novel partially reduced ligands 3a-3d were synthesized from 1a-1d according to a known literature protocol for the selective monoreduction of bisphosphine oxides. The neutral yttrium complexes 2a-2d are nine-coordinate and display a tricapped trigonal-prismatic geometry. Complexes 4a-4d are also neutral, nine-coordinate species and have a pendant phosphine functionality, which provides the potential to form bimetallic early-late transition-metal complexes. Additionally, yttrium complexes 2a-2d were activated with base and tested for the ring-opening polymerization of ε-caprolactone, but the results showed that base by itself was significantly more effective than the yttrium species investigated.

  15. Spin-Hall magnetoresistance in platinum on yttrium iron garnet : Dependence on platinum thickness and in-plane/out-of-plane magnetization

    NARCIS (Netherlands)

    Vlietstra, N.; Shan, J.; Castel, V.; van Wees, B. J.; Ben Youssef, J.

    2013-01-01

    The occurrence of spin-Hall magnetoresistance (SMR) in platinum (Pt) on top of yttrium iron garnet (YIG) has been investigated, for both in-plane and out-of-plane applied magnetic fields and for different Pt thicknesses [3, 4, 8, and 35 nm]. Our experiments show that the SMR signal directly depends

  16. Simultaneous detection of the spin-Hall magnetoresistance and the spin-Seebeck effect in platinum and tantalum on yttrium iron garnet

    NARCIS (Netherlands)

    Vlietstra, N.; Shan, J.; van Wees, B. J.; Isasa, M.; Casanova, F.; Ben Youssef, J.

    2014-01-01

    The spin-Seebeck effect (SSE) in platinum (Pt) and tantalum (Ta) on yttrium iron garnet has been investigated by both externally heating the sample (using an on-chip Pt heater on top of the device) and by current-induced heating. For SSE measurements, external heating is the most common method to ob

  17. Influence of potassium on the competition between methane and ethane in steam reforming over Pt supported on yttrium-stabilized zirconia

    NARCIS (Netherlands)

    Graf, Patrick O.; Mojet, Barbara L.; Lefferts, Leon

    2008-01-01

    effect of addition of potassium to Pt supported on yttrium-stabilized zirconia (PtYSZ) catalyst for steam reforming of methane, ethane and methane/ethane mixtures was explored. Addition of potassium has a positive effect on preferential steam reforming of methane in mixtures of methane and ethane ov

  18. Synthesis and characterization of a novel acryl amide-based yttrium imprinted sorbent via the ATRP approach for the preparation of medical-grade {sup 90}Y

    Energy Technology Data Exchange (ETDEWEB)

    Abedi, Mahvash [Nuclear Schience and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of); Shahid Beheshti Univ., Tehran (Iran, Islamic Republic of). Dept. of Chemistry; Shirvani-Arani, Simindokht; Bahrami-Samani, Ali [Nuclear Schience and Technology Research Institute (NSTRI), Tehran (Iran, Islamic Republic of); Nabid, Mohammad Reza [Shahid Beheshti Univ., Tehran (Iran, Islamic Republic of). Dept. of Chemistry

    2016-05-01

    Because of its favorable radionuclidic properties (pure beta emitter, E{sub βmax} = 2.28 MeV, T{sub 1/2} = 64.1 h), the preparation of carrier free {sup 90}Y is of a great importance in radiopharmacy. Herein, we report the synthesis, characterization, and application of a novel yttrium sorbent prepared on the basis of the ion-imprinting concept. The ion-imprinted polymer (IIP) was prepared by atom transfer radical copolymerization of acryl amide (AAm, functional monomer) and N,N'-methylenebisacrylamide (MBAAm) crosslinking agent in the presence of a complex of yttrium ions (template ions) with a homemade chelator, i.e., 2,2-bis(2-bromo-2-methylpropanoate)propane-1,3-disuccinate (also as initiator). For elimination of yttrium ions, which act as the template, the prepared particles were treated with 50% v:v HCl: H{sub 2}O to produce yttrium-imprinted polymeric sorbent. To control the imprinting effect, corresponding non-imprinted particles (NIP) were prepared in a similar manner except that yttrium ions were not used. The synthesized chemicals for the preparation of the chelator-initiator compound and the product itself were assessed in every step using {sup 1}H-NMR analysis. NIP and YIP were subjected to X-ray diffraction (XRD), infra-red spectroscopy (IR) and BET surface area analysis for characterization studies. Sorption/desorption studies were conducted, and the effects of potentially interfering ions, such as Sr{sup 2+} (α = 119.69) and Zr{sup 4+} (α = 73.01) in presence of radio-yttrium, were investigated (particle size: 50-100 μm, resultant recovery of > 99% within 60 min and a capacity of 33.33 mg Y(III) per gram of sorbent). The results showed that amounts of radio-yttrium as low as 250 μg could be extracted effectively with high radionuclidic and radiochemical purity from macro-gram amounts of strontium.

  19. [Analysis of tartrazine aluminum lake and sunset yellow aluminum lake in foods by capillary zone electrophoresis].

    Science.gov (United States)

    Zhang, Yiding; Chang, Cuilan; Guo, Qilei; Cao, Hong; Bai, Yu; Liu, Huwei

    2014-04-01

    A novel analytical method for tartrazine aluminum lake and sunset yellow aluminum lake using capillary zone electrophoresis (CZE) was studied. The pigments contained in the color lakes were successfully separated from the aluminum matrix in the pre-treatment process, which included the following steps: dissolve the color lakes in 0.1 mol/L H2SO4, adjust the pH of the solution to 5.0, then mix it with the solution of EDTA x 2Na and heat it in a water bath, then use polyamide powder as the stationary phase of solid phase extraction to separate the pigments from the solution, and finally elute the pigments with 0.1 mol/L NaOH. The CZE conditions systematically optimized for tartrazine aluminum lake were: 48.50 cm of a fused silica capillary with 40.00 cm effective length and 50 microm i. d., the temperature controlled at 20.0 degrees C, 29.0 kV applied, HPO4(2-)-PO4(3-) (0.015 mol/L, pH 11.45) solution as running buffer, detection at 263 nm. The conditions for sunset yellow aluminum lake were: the same capillary and temperature, 25.0 kV applied, HPO4(2-)-PO4(3-) (0.025 mol/L, pH 11.45) solution as running buffer, detection at 240 nm. The limits of detection were 0.26 mg/L and 0.27 mg/L, and the linear ranges were 0.53-1.3 x 10(2) mg/L and 0.54-1.4 x 10(2) mg/L for tartrazine aluminum lake and sunset yellow aluminum lake, respectively. The RSDs were 4.3% and 5.7% (run to run, n = 6), 5.6% and 6.0% (day to day, n = 6) for tartrazine aluminum lake and sunset yellow aluminum lake, respectively. Further developments for this method could make it a routinely used method analyzing color lakes in foods.

  20. Aluminum nanocomposites for elevated temperature applications

    Science.gov (United States)

    Borgonovo, C.; Apelian, D.; Makhlouf, M. M.

    2011-02-01

    Aluminum casting alloys conventionally used in the automotive and aerospace industries (i.e., Al-Zn-Mg, and Al-Cu-Mg systems) are able to achieve excellent tensile strength at room temperature. At high temperatures, such alloys lose dimensional stability and their mechanical properties rapidly degrade. Aluminum-based nanocomposites show the potential for enhanced performance at high temperatures. The manufacturing process, however, is difficult; a viable and effective method for large-scale applications has not been developed. In the current study, an innovative and cost-effective approach has been adopted to manufacture Al/AlN composites. A nitrogen-bearing gas is injected into the melt and AlN particles synthesize in-situ via chemical reaction. In a preliminary stage, a model able to predict the amount of reinforcement formed has been developed. AlN dispersoids have been succesfully synthesized in the matrix and the model has been experimentally validated.

  1. Generation and structural characterization of aluminum cyanoacetylide

    Energy Technology Data Exchange (ETDEWEB)

    Cabezas, Carlos; Peña, Isabel; Alonso, José L., E-mail: alargo@qf.uva.es, E-mail: jlalonso@qf.uva.es [Grupo de Espectroscopia Molecular (GEM), Edificio Quifima, Laboratorios de Espectroscopia y Bioespectroscopia, Unidad Asociada CSIC, Parque Científico Uva, Universidad de Valladolid, Paseo de Belén 5, 47011 Valladolid (Spain); Barrientos, Carmen; Largo, Antonio, E-mail: alargo@qf.uva.es, E-mail: jlalonso@qf.uva.es [Departamento de Química Física y Química Inorgánica, Facultad de Ciencias, Universidad de Valladolid, Campus Miguel Delibes, Paseo de Belén 7, 47011 Valladolid (Spain); Guillemin, Jean-Claude [Institut des Sciences Chimiques de Rennes, École Nationale Supérieure de Chimie de Rennes, CNRS, UMR 6226, 11 Allée de Beaulieu, CS 50837, 35708 Rennes Cedex 7 (France); Cernicharo, José [Group of Molecular Astrophysics, ICMM C/Sor Juana Ines de la Cruz N3 Cantoblanco, 28049 Madrid (Spain)

    2014-09-14

    Combined spectroscopy measurements and theoretical calculations bring to light a first investigation of a metallic cyanoacetylide, AlC{sub 3}N, using laser ablation molecular beam Fourier transform microwave spectroscopy. This molecule was synthesized in a supersonic expansion by the reaction of aluminum vapour with C{sub 3}N, produced from solid aluminum rods and BrCCCN in a newly constructed ablation-heating nozzle device. A set of accurate rotational and {sup 27}Al and {sup 14}N nuclear quadrupole coupling constants have been determined from the analysis of the rotational spectrum and compared with those predicted in a high-level ab initio study, conducting to the assignment of the observed species to linear AlCCCN. We have searched for this species towards the carbon-rich evolved star IRC + 10216 but only an upper limit to its abundance has been obtained.

  2. Generation and structural characterization of aluminum cyanoacetylide

    Science.gov (United States)

    Cabezas, Carlos; Barrientos, Carmen; Largo, Antonio; Guillemin, Jean-Claude; Cernicharo, José; Peña, Isabel; Alonso, José L.

    2015-01-01

    Combined spectroscopy measurements and theoretical calculations bring to light a first investigation of a metallic cyanoacetylide, AlC3N, using laser ablation molecular beam Fourier transform microwave spectroscopy. This molecule was synthesized in a supersonic expansion by the reaction of aluminum vapour with C3N, produced from solid aluminum rods and BrCCCN in a newly constructed ablation-heating nozzle device. A set of accurate rotational and 27Al and 14N nuclear quadrupole coupling constants have been determined from the analysis of the rotational spectrum and compared with those predicted in a high-level ab initio study, conducting to the assignment of the observed species to linear AlCCCN. We have searched for this species towards the carbon-rich evolved star IRC + 10216 but only an upper limit to its abundance has been obtained. PMID:25217914

  3. Fluorescence energy transfer enhancement in aluminum nanoapertures

    CERN Document Server

    de Torres, Juan; Moparthi, Satish Babu; Grigoriev, Victor; Wenger, Jérome

    2015-01-01

    Zero-mode waveguides (ZMWs) are confining light into attoliter volumes, enabling single molecule fluorescence experiments at physiological micromolar concentrations. Among the fluorescence spectroscopy techniques that can be enhanced by ZMWs, F\\"{o}rster resonance energy transfer (FRET) is one of the most widely used in life sciences. Combining zero-mode waveguides with FRET provides new opportunities to investigate biochemical structures or follow interaction dynamics at micromolar concentration with single molecule resolution. However, prior to any quantitative FRET analysis on biological samples, it is crucial to establish first the influence of the ZMW on the FRET process. Here, we quantify the FRET rates and efficiencies between individual donor-acceptor fluorophore pairs diffusing in aluminum zero-mode waveguides. Aluminum ZMWs are important structures thanks to their commercial availability and the large literature describing their use for single molecule fluorescence spectroscopy. We also compare the ...

  4. Etching Behavior of Aluminum Alloy Extrusions

    Science.gov (United States)

    Zhu, Hanliang

    2014-11-01

    The etching treatment is an important process step in influencing the surface quality of anodized aluminum alloy extrusions. The aim of etching is to produce a homogeneously matte surface. However, in the etching process, further surface imperfections can be generated on the extrusion surface due to uneven materials loss from different microstructural components. These surface imperfections formed prior to anodizing can significantly influence the surface quality of the final anodized extrusion products. In this article, various factors that influence the materials loss during alkaline etching of aluminum alloy extrusions are investigated. The influencing variables considered include etching process parameters, Fe-rich particles, Mg-Si precipitates, and extrusion profiles. This study provides a basis for improving the surface quality in industrial extrusion products by optimizing various process parameters.

  5. Generation and structural characterization of aluminum cyanoacetylide

    Science.gov (United States)

    Cabezas, Carlos; Barrientos, Carmen; Largo, Antonio; Guillemin, Jean-Claude; Cernicharo, José; Peña, Isabel; Alonso, José L.

    2014-09-01

    Combined spectroscopy measurements and theoretical calculations bring to light a first investigation of a metallic cyanoacetylide, AlC3N, using laser ablation molecular beam Fourier transform microwave spectroscopy. This molecule was synthesized in a supersonic expansion by the reaction of aluminum vapour with C3N, produced from solid aluminum rods and BrCCCN in a newly constructed ablation-heating nozzle device. A set of accurate rotational and 27Al and 14N nuclear quadrupole coupling constants have been determined from the analysis of the rotational spectrum and compared with those predicted in a high-level ab initio study, conducting to the assignment of the observed species to linear AlCCCN. We have searched for this species towards the carbon-rich evolved star IRC + 10216 but only an upper limit to its abundance has been obtained.

  6. Aluminum matrix composites reinforced with alumina nanoparticles

    CERN Document Server

    Casati, Riccardo

    2016-01-01

    This book describes the latest efforts to develop aluminum nanocomposites with enhanced damping and mechanical properties and good workability. The nanocomposites exhibited high strength, improved damping behavior and good ductility, making them suitable for use as wires. Since the production of metal matrix nanocomposites by conventional melting processes is considered extremely problematic (because of the poor wettability of the nanoparticles), different powder metallurgy routes were investigated, including high-energy ball milling and unconventional compaction methods. Special attention was paid to the structural characterization at the micro- and nanoscale, as uniform nanoparticle dispersion in metal matrix is of prime importance. The aluminum nanocomposites displayed an ultrafine microstructure reinforced with alumina nanoparticles produced in situ or added ex situ. The physical, mechanical and functional characteristics of the materials produced were evaluated using different mechanical tests and micros...

  7. Novel routes to metalloorganics containing aluminum from minerals

    Science.gov (United States)

    Narayanan, Ramasubramanian

    Novel pathways for synthesizing Al metalloorganics directly from widely available oxides and oxo-hydroxides of aluminum are developed. The Al metalloorganics are then used to produce low-cost precursors for ceramics and polymers containing Al. Alumatrane, an unique, air-stable, aluminum alkoxide is prepared in one step from aluminum hydroxide in quantitative yields. Subsequently, alumatrane was used to prepare and characterize all group II dialuminate ceramics (MAlsb2Osb4, M = Mg, Ca, Sr, Ba). Similarly, an air-stable alkoxide of silicon was synthesized directly from SiOsb2, and is used in conjunction with alumatrane to produce precursors for aluminosilicate ceramics (MAlSiOsb4, M = K, Li, Na). Aluminum formate is synthesized, in differing efficiencies, from different crystalline minerals of Al, by direct dissolution in formic acid. A few other aluminum carboxylates are also synthesized, either directly from minerals or from aluminum formates, thus expanding the scope of the acid dissolution of aluminum hydroxides. Aluminum allyloxypropanoate (AAP) (Al(Osb2CCHsb2CHsb2OCH{=}CHsb2)sb2(OH)), an aluminum carboxylate with a polymerizable group has been synthesized from aluminum formate. This, has been incorporated into methyl methacrylate (MMA) polymers to impart fire retardancy. The increase in char yields as a result of AAP incorporation, indicate improved fire retardancy. Fire retardant characteristics of alumatrane has also been investigated, in MMA polymers and in a polyurethane polymer, taking char yields as a measure of fire retardance efficiency.

  8. A Positron Annihilation Study of Corrosion of Aluminum and Aluminum Alloy by NaOH

    Science.gov (United States)

    Wu, Y. C.; Zhai, T.; Coleman, P. G.

    2012-08-01

    Corrosion of fully-annealed pure aluminum and a continuous-cast AA2037 aluminum alloy (solutionized and water quenched) in a 1M NaOH solution for various periods of time were analyzed with positron beam-based Doppler broadening spectroscopy. By varying the energy of the incident positron beam, corrosion-induced defects at different depths from the surface were detected. It was found that the Doppler-broadened annihilation line-width parameter was significantly increased near the surface of pure aluminum after corrosion, probably due to the interaction between positrons and nanometer-sized voids formed near the aluminum surface during corrosion. Examination by atomic force microscopy indicated that many pits were formed on the aluminum surface after corrosion. In contrast, a significant decrease in the line-width parameter was observed in AA2037 alloy after corrosion and interpreted as being caused by copper enrichment at the metal-oxide interface during corrosion; such enrichment at large cavity sites was confirmed by energy dispersion spectrometry.

  9. Aluminum alloy nanosecond vs femtosecond laser marking

    Indian Academy of Sciences (India)

    S Rusu; A Buzaianu; D G Galusca; L Ionel; D Ursescu

    2013-11-01

    Based on the lack of consistent literature publications that analyse the effects of laser marking for traceability on various materials, the present paper proposes a study of the influence of such radiation processing on an aluminum alloy, a vastly used material base within several industry fields. For the novelty impact, femtolaser marking has been carried out, besides the standard commercial nanosecond engraving. All the marks have been analysed using profilometry, overhead and cross-section SEM microscopy, respectively and EDAX measurements.

  10. Testing conformal mapping with kitchen aluminum foil

    CERN Document Server

    Haas, S; Crivelli, P

    2016-01-01

    We report an experimental verification of conformal mapping with kitchen aluminum foil. This experiment can be reproduced in any laboratory by undergraduate students and it is therefore an ideal experiment to introduce the concept of conformal mapping. The original problem was the distribution of the electric potential in a very long plate. The correct theoretical prediction was recently derived by A. Czarnecki (Can. J. Phys. 92, 1297 (2014)).

  11. Spin Forming of Aluminum Metal Matrix Composites

    Science.gov (United States)

    Lee, Jonathan A.; Munafo, Paul M. (Technical Monitor)

    2001-01-01

    An exploratory effort between NASA-Marshall Space Flight Center (MSFC) and SpinCraft, Inc., to experimentally spin form cylinders and concentric parts from small and thin sheets of aluminum Metal Matrix Composites (MMC), successfully yielded good microstructure data and forming parameters. MSFC and SpinCraft will collaborate on the recent technical findings and develop strategy to implement this technology for NASA's advanced propulsion and airframe applications such as pressure bulkheads, combustion liner assemblies, propellant tank domes, and nose cone assemblies.

  12. Why Electrolytic Aluminum Overcapacity Lingering for Years

    Institute of Scientific and Technical Information of China (English)

    Yan Manman

    2009-01-01

    @@ According to the Opinions on Restraining Overcapacity and Redundant Construction in Parts of Industries and Leading the Healthy Development of Industries" (Hereafter short for OPINIONS) promulgated by ten ministries and emphasized by the State Council,the electrolytic aluminum capacity in China is 18 million tons,accounting for 42.9% of the global capacity,and the capacity utility rate is only 73.2%.

  13. Composite hydrophilic coating for conditioner aluminum fins

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    To solve the so-called "white rust" and 'water bridge" problems of the aluminum fins for heat exchanger of automobile air conditioner, aimed at nationalizing the art of hydrophilic coating technology, the choice of coating forming and curing materials was investigated. By measuring the water contact angle, SEM surface scanning and ingredients analysis of the coating, optimal parameters and composition are acquired. The coating forming mechanisms of the composition was also expatiated. The coating obtained has good hydrophilic and other properties.

  14. Anodizing And Sealing Aluminum In Nonchromated Solutions

    Science.gov (United States)

    Emmons, John R.; Kallenborn, Kelli J.

    1995-01-01

    Improved process for anodizing and sealing aluminum involves use of 5 volume percent sulfuric acid in water as anodizing solution, and 1.5 to 2.0 volume percent nickel acetate in water as sealing solution. Replaces process in which sulfuric acid used at concentrations of 10 to 20 percent. Improved process yields thinner coats offering resistance to corrosion, fatigue life, and alloy-to-alloy consistency equal to or superior to those of anodized coats produced with chromated solutions.

  15. Electrochemical Studies in Aluminum Chloride Melts

    Science.gov (United States)

    1976-07-31

    Molten Salt Systems", Symposium on Molten Salts, Symposium Volume, The Electrochemical Society , in press (1976). Manuscripts in Preparation--Related to...Fused Salt Technology, Electrochemical Society Meeting, Chicaao, May 8-13, 1973. R. A. Osteryoung, R. H. Abel, L. G. Boxall and B. H. Vassos, "An...aluminate Melts", Electrochemical Society , San Francisco, CA, May, 1974. R. A. Osteryoung, "Chemistry in Aluminum Chloride Melts", Fifth International

  16. Preparation and characterization of aluminum stearate

    Directory of Open Access Journals (Sweden)

    Lončar Eva S.

    2003-01-01

    Full Text Available Preparation of aluminum stearate by the precipitation method was examined under various conditions of stearic acid saponification with sodium hydroxide. It was proved that the most favorable ratio of acid/alkali was 1:1.5 and that the obtained soap was very similar to the commercial product. Endothermic effects determined by differential scanning calorimetry and also the other parameters showed that the soaps consisted mono-, di-, tristearates and non-reacted substances, where distearate was the dominant form.

  17. Magnesium Aluminum Borides as Explosive Materials

    Science.gov (United States)

    2011-12-20

    Figure 1). Hsia argued that compounds that do not undergo decomposition reactions are better choices for rocket propellants since the endothermic ...decomposition reaction is undesired. The endotherm for AlB2 decomposition, however, is small[13], especially when compared to the heat of combustion... exotherms for the boron carbide materials are comparable to those of Al + 2B and AlB2. 40 Figure 23. TGA of silicon borides vs . aluminum borides

  18. One-step synthesis of layered yttrium hydroxides in immiscible liquid–liquid systems: Intercalation of sterically-bulky hydrophobic organic anions and doping of europium ions

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Mebae; Fujihara, Shinobu, E-mail: shinobu@applc.keio.ac.jp

    2014-02-15

    Inorganic–organic layered rare-earth compounds were synthesized on the basis of a biphasic liquid–liquid system in one pot. Layered yttrium hydroxides (LYHs) were chosen as a host material for the intercalation of hydrophobic organic guest anions such as benzoate, sebacate, or laurate. In a typical synthesis, an organic phase dissolving carboxylic acid was placed in contact with an equal amount of an aqueous phase dissolving yttrium nitrate n-hydrate and urea. At elevated temperatures up to 80 °C, urea was hydrolyzed to release hydroxyl anions which were used to form yttrium hydroxide layers. LYHs were then precipitated with the intercalation of carboxylate anions delivered from the organic phase under the distribution law. The structure and the morphology of the LYHs could be modulated by the intercalated anions. Doped with Eu{sup 3+} ions, the LYHs exhibited red photoluminescence which was enhanced by the intercalated anions due to the antenna effect. - Graphical abstract: The Eu{sup 3+}-doped layered yttrium hydroxide exhibits intense red photoluminescence after intercalation of benzoate ions. Display Omitted - Highlights: • Immiscible biphasic liquid systems were introduced to synthesize layered yttrium hydroxides. • The temperature of the biphasic systems does not exceed 80 °C in one step of the synthesis. • Hydrophobic organic anions were intercalated between the hydroxide layers in one pot. • Structure and morphology of the hydroxides were modulated by changing the kind of organic anions. • Eu{sup 3+}-doping led to red luminescence from the hydroxides in association with the intercalated organic anions.

  19. Fatigue performance of welded aluminum deck structures

    Energy Technology Data Exchange (ETDEWEB)

    Haagensen, P.J.; Ranes, M.; Kluken, A.O.; Kvale, I.

    1996-12-01

    Aluminum alloys are used increasingly in load carrying structures where low weight and low maintenance costs are at a premium. Helicopter decks, structures for living quarters and personnel transfer bridges between platforms are examples of offshore applications. While these structures are not usually subjected to high fatigue loads, the increasing use of aluminum in high speed ships, and more recently in highway bridge structures, makes the question of fatigue performance more important. In this paper the fatigue properties of small scale weldments in an AA6005 alloy are compared with the results of fatigue tests on full scale sections of welded extrusions in the same material, which were used in an aluminum bridge deck structure. The fatigue performance is also compared with the fatigue clauses in the new British design code BS8118 for aluminium structures and the proposed Eurocode 9. The prospects of using a new joining technique, friction stir welding (FSW), in the production of large scale panels for deck and ship hull structures is discussed. The FSW process is described briefly, and some fatigue test data are presented.

  20. Chromic acid anodizing of aluminum foil

    Science.gov (United States)

    Dursch, H.

    1988-01-01

    The success of the Space Station graphite/epoxy truss structure depends on its ability to endure long-term exposure to the LEO environment, primarily the effects of atomic oxygen and the temperture cycling resulting from the 94 minute orbit. This report describes the development and evaluation of chromic acid anodized (CAA) aluminum foil as protective coatings for these composite tubes. Included are: development of solar absorptance and thermal emittance properties required of Al foil and development of CAA parameters to achieve these optical properties; developing techniques to CAA 25 ft lengths of Al foil; developing bonding processes for wrapping the Al foil to graphite/epoxy tubes; and atomic oxygen testing of the CAA Al foil. Two specifications were developed and are included in the report: Chromic Acid Anodizing of Aluminum Foil Process Specification and Bonding of Anodized Aluminum Foil to Graphite/Epoxy Tubes. Results show that CAA Al foil provides and excellent protective and thermal control coating for the Space Station truss structure.