Color stable phosphors for LED lamps and methods for preparing them

DOEpatents

Murphy, James Edward; Setlur, Anant Achyut; Camardello, Samuel Joseph

2013-11-26

An LED lamp includes a light source configured to emit radiation with a peak intensity at a wavelength between about 250 nm and about 550 nm; and a phosphor composition configured to be radiationally coupled to the light source. The phosphor composition includes particles of a phosphor of formula I, said particles having a coating composition disposed on surfaces thereof; ((Sr.sub.1-zM.sub.z).sub.1-(x+w)A.sub.wCe.sub.x).sub.3(Al.sub.1-ySi.sub.y-)O.sub.4+y+3(x-w)F.sub.1-y-3(x-w) I wherein the coating composition comprises a material selected from aluminum oxide, magnesium oxide, calcium oxide, barium oxide, strontium oxide, zinc oxide, aluminum hydroxide, magnesium hydroxide, calcium hydroxide, barium hydroxide, strontium hydroxide, zinc hydroxide, aluminum phosphate, magnesium phosphate, calcium phosphate, barium phosphate, strontium phosphate, and combinations thereof; and A is Li, NA, K, or Rb, or a combination thereof; M is Ca, Ba, Mg, Zn, or a combination thereof; and 0

Experiments On Transparent Conductive Films For Spacecraft

NASA Technical Reports Server (NTRS)

Perez-Davis, Marla E.; Rutledge, Sharon K.; De Groh, Kim K.; Hung, Ching-Cheh; Malave-Sanabria, Tania; Hambourger, Paul; Roig, David

1995-01-01

Report describes experiments on thin, transparent, electrically conductive films made, variously, of indium tin oxide covered by magnesium fluoride (ITO/MgF2), aluminum-doped zinc oxide (AZO), or pure zinc oxide (ZnO). Films are candidates for application to such spacecraft components, including various optoelectronic devices and window surfaces that must be protected against buildup of static electric charge. On Earth, such films useful on heat mirrors, optoelectronic devices, gas sensors, and automotive and aircraft windows.

High Stability Performance of Quinary Indium Gallium Zinc Aluminum Oxide Films and Thin-Film Transistors Deposited Using Vapor Cooling Condensation Method

NASA Astrophysics Data System (ADS)

Lin, Yung-Hao; Lee, Ching-Ting

2017-08-01

High-quality indium gallium zinc aluminum oxide (IGZAO) thin films with various Al contents have been deposited using the vapor cooling condensation method. The electron mobility of the IGZAO films was improved by 89.4% on adding Al cation to IGZO film. The change in the electron concentration and mobility of the IGZAO films was 7.3% and 7.0%, respectively, when the temperature was changed from 300 K to 225 K. These experimental results confirm the high performance and stability of the IGZAO films. The performance stability mechanisms of IGZAO thin-film transistors (TFTs) were investigated in comparison with IGZO TFTs.

21 CFR 82.2051 - Lakes (Ext. D&C).

Code of Federal Regulations, 2010 CFR

2010-04-01

..., titanium dioxide, zinc oxide, talc, rosin, aluminum benzoate, calcium carbonate, or on any combination of... is a salt in which is combined the basic radical sodium, potassium, barium, or calcium; or (ii) a... color with the basic radical sodium, potassium, aluminum, barium, calcium, strontium, or zirconium. (2...

21 CFR 82.2051 - Lakes (Ext. D&C).

Code of Federal Regulations, 2012 CFR

2012-04-01

..., titanium dioxide, zinc oxide, talc, rosin, aluminum benzoate, calcium carbonate, or on any combination of... is a salt in which is combined the basic radical sodium, potassium, barium, or calcium; or (ii) a... color with the basic radical sodium, potassium, aluminum, barium, calcium, strontium, or zirconium. (2...

21 CFR 82.2051 - Lakes (Ext. D&C).

Code of Federal Regulations, 2013 CFR

2013-04-01

..., titanium dioxide, zinc oxide, talc, rosin, aluminum benzoate, calcium carbonate, or on any combination of... is a salt in which is combined the basic radical sodium, potassium, barium, or calcium; or (ii) a... color with the basic radical sodium, potassium, aluminum, barium, calcium, strontium, or zirconium. (2...

21 CFR 82.2051 - Lakes (Ext. D&C).

Code of Federal Regulations, 2014 CFR

2014-04-01

..., titanium dioxide, zinc oxide, talc, rosin, aluminum benzoate, calcium carbonate, or on any combination of... is a salt in which is combined the basic radical sodium, potassium, barium, or calcium; or (ii) a... color with the basic radical sodium, potassium, aluminum, barium, calcium, strontium, or zirconium. (2...

21 CFR 82.2051 - Lakes (Ext. D&C).

Code of Federal Regulations, 2011 CFR

2011-04-01

..., titanium dioxide, zinc oxide, talc, rosin, aluminum benzoate, calcium carbonate, or on any combination of... is a salt in which is combined the basic radical sodium, potassium, barium, or calcium; or (ii) a... color with the basic radical sodium, potassium, aluminum, barium, calcium, strontium, or zirconium. (2...

Method for making an aluminum or copper substrate panel for selective absorption of solar energy

NASA Technical Reports Server (NTRS)

Roberts, M. L.; Sharpe, M. H.; Krupnick, A. C. (Inventor)

1978-01-01

A panel is described for selectively absorbing solar energy comprising an aluminum substrate. A zinc layer was covered by a layer of nickel and an outer layer of solar energy absorbing nickel oxide or a copper substrate with a nickel layer. A layer of solar energy absorbing nickel oxide distal from the copper substrate was included. A method for making these panels is disclosed.

Viscosity, density, and thermal conductivity of aluminum oxide and zinc oxide nanolubricants

PubMed Central

Kedzierski, M.A.; Brignoli, R.; Quine, K.T.; Brown, J.S.

2017-01-01

This paper presents liquid kinematic viscosity, density, and thermal conductivity measurements of eleven different synthetic polyolester-based nanoparticle nanolubricants (dispersions) at atmospheric pressure over the temperature range 288 K to 318 K. Aluminum oxide (Al2O3) and zinc oxide (ZnO) nanoparticles with nominal diameters of 127 nm and 135 nm, respectively, were investigated. A good dispersion of the spherical and non-spherical nanoparticles in the lubricant was maintained with a surfactant. Viscosity, density, and thermal conductivity measurements were made for the neat lubricant along with eleven nanolubricants with differing nanoparticle and surfactant mass fractions. Existing models were used to predict kinematic viscosity (±20%), thermal conductivity (±1%), and specific volume (±6%) of the nanolubricant as a function of temperature, nanoparticle mass fraction, surfactant mass fraction, and nanoparticle diameter. The liquid viscosity, density and thermal conductivity were shown to increase with respect to increasing nanoparticle mass fraction. PMID:28736463

Aluminium or copper substrate panel for selective absorption of solar energy

NASA Technical Reports Server (NTRS)

Roberts, M. L.; Sharpe, M. H.; Krupnick, A. C. (Inventor)

1979-01-01

A method for making panels which selectively absorb solar energy is disclosed. The panels are comprised of an aluminum substrate, a layer of zinc thereon, a layer of nickel over the zinc layer and an outer layer of solar energy absorbing nickel oxide or a copper substrate with a layer of nickel thereon and a layer of solar energy absorbing nickel oxide distal from the copper substrate.

Hybrid Co-deposition of Mixed-Valent Molybdenum-Germanium Oxides (MoxGeyOz): A Route to Tunable Optical Transmission (Postprint)

DTIC Science & Technology

2015-08-05

to increased doping levels in indirect semiconductors [84]. The slope, and magnitude of the transmission curves continue to decrease alongside UL...periodically aluminium- doped zinc oxide thin films, Thin Solid Films 519 (2011) 2280–2286. [2] T. Minami, H. Nanto, S. Takata, Highly conductive and...transparent aluminum doped zinc oxide thin films prepared by RF magnetron sputtering, Jpn. J. Appl. Phys. 23 (1984) L280. [3] T. Minami, Present status of

Improvement of Self-Heating of Indium Gallium Zinc Aluminum Oxide Thin-Film Transistors Using Al2O3 Barrier Layer

NASA Astrophysics Data System (ADS)

Jian, Li-Yi; Lee, Hsin-Ying; Lin, Yung-Hao; Lee, Ching-Ting

2018-02-01

To study the self-heating effect, aluminum oxide (Al2O3) barrier layers of various thicknesses have been inserted between the channel layer and insulator layer in bottom-gate-type indium gallium zinc aluminum oxide (IGZAO) thin-film transistors (TFTs). Each IGZAO channel layer was deposited on indium tin oxide (ITO)-coated glass substrate by using a magnetron radiofrequency cosputtering system with dual targets composed of indium gallium zinc oxide (IGZO) and Al. The 3 s orbital of Al cation provided an extra transport pathway and widened the conduction-band bottom, thus increasing the electron mobility of the IGZAO films. The Al-O bonds were able to sustain the oxygen stability of the IGZAO films. The self-heating behavior of the resulting IGZAO TFTs was studied by Hall measurements on the IGZAO films as well as the electrical performance of the IGZAO TFTs with Al2O3 barrier layers of various thicknesses at different temperatures. IGZAO TFTs with 50-nm-thick Al2O3 barrier layer were stressed by positive gate bias stress (PGBS, at gate-source voltage V GS = 5 V and drain-source voltage V DS = 0 V); at V GS = 5 V and V DS = 10 V, the threshold voltage shifts were 0.04 V and 0.2 V, respectively, much smaller than for the other IGZAO TFTs without Al2O3 barrier layer, which shifted by 0.2 V and 1.0 V when stressed under the same conditions.

77 FR 64311 - Potential Market Impact of the Proposed Fiscal Year 2014 Annual Materials Plan; National Defense...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-10-19

...,000 (5) Cadmium Zinc Tellurium (CZT) substrates.. cm\\2\\ 24,000 (6) Lithium Cobalt Oxide (LCO) Kg 750 (6) Lithium Nickel Cobalt Aluminum Oxide kg 540 (6) (NCA). Mesocarbon Microbeads (MCMB) kg 648 (6...

Relative SHG measurements of metal thin films: Gold, silver, aluminum, cobalt, chromium, germanium, nickel, antimony, titanium, titanium nitride, tungsten, zinc, silicon and indium tin oxide

NASA Astrophysics Data System (ADS)

Che, Franklin; Grabtchak, Serge; Whelan, William M.; Ponomarenko, Sergey A.; Cada, Michael

We have experimentally measured the surface second-harmonic generation (SHG) of sputtered gold, silver, aluminum, zinc, tungsten, copper, titanium, cobalt, nickel, chromium, germanium, antimony, titanium nitride, silicon and indium tin oxide thin films. The second-harmonic response was measured in reflection using a 150 fs p-polarized laser pulse at 1561 nm. We present a clear comparison of the SHG intensity of these films relative to each other. Our measured relative intensities compare favorably with the relative intensities of metals with published data. We also report for the first time to our knowledge the surface SHG intensity of tungsten and antimony relative to that of well known metallic thin films such as gold and silver.

New CVD-based method for the growth of high-quality crystalline zinc oxide layers

NASA Astrophysics Data System (ADS)

Huber, Florian; Madel, Manfred; Reiser, Anton; Bauer, Sebastian; Thonke, Klaus

2016-07-01

High-quality zinc oxide (ZnO) layers were grown using a new chemical vapour deposition (CVD)-based low-cost growth method. The process is characterized by total simplicity, high growth rates, and cheap, less hazardous precursors. To produce elementary zinc vapour, methane (CH4) is used to reduce a ZnO powder. By re-oxidizing the zinc with pure oxygen, highly crystalline ZnO layers were grown on gallium nitride (GaN) layers and on sapphire substrates with an aluminum nitride (AlN) nucleation layer. Using simple CH4 as precursor has the big advantage of good controllability and the avoidance of highly toxic gases like nitrogen oxides. In photoluminescence (PL) measurements the samples show a strong near-band-edge emission and a sharp line width at 5 K. The good crystal quality has been confirmed in high resolution X-ray diffraction (HRXRD) measurements. This new growth method has great potential for industrial large-scale production of high-quality single crystal ZnO layers.

Use Of New Industrial Coatings for the U.S. Navy Waterfront Structures

DTIC Science & Technology

2008-01-01

as a coating for the interior and exterior of piping systems, which either are located in harsh environments or are transporting substances with...SSPC SP 10 Surfaces) (5). SyslCm Coating Sys\\~m A Zinc -rich urethane/MIOa·filled urethane/urethane 314/315/314 B Zinc -rich urethane/MIO-filled...urethanc/MIO-urethane 336/3361336 C Zinc -rich urethancl1vfiO & Alb-fined urethaneiMIO-fiIled 337/3401336 ,1 MicaceQus iron oxide. b Aluminum. urethane

Low-Frequency Noise in Amorphous Indium Zinc Oxide Thin Film Transistors with Aluminum Oxide Gate Insulator

NASA Astrophysics Data System (ADS)

Chen, Ya-Yi; Liu, Yuan; Wu, Zhao-Hui; Wang, Li; Li, Bin; En, Yun-Fei; Chen, Yi-Qiang

2018-04-01

Not Available Supported by the National Natural Science Foundation of China under Grant No 61574048, the Science and Technology Research Project of Guangdong Province under Grant Nos 2015B090912002 and 2015B090901048, and the Pearl River S&T Nova Program of Guangzhou under Grant No 201710010172.

Characterizing and simulation the scintillation properties of zinc oxide nanowires in AAO membrane for medical imaging applications

NASA Astrophysics Data System (ADS)

Esfandi, F.; Saramad, S.; Rezaei Shahmirzadi, M.

2017-07-01

In this work, a new method is proposed for extracting some X-ray detection properties of ZnO nanowires electrodeposited on Anodized Aluminum Oxide (AAO) nanoporous template. The results show that the detection efficiency for 12μm thickness of zinc oxide nano scintillator at an energy of 9.8 keV, near the K-edge of ZnO (9.65 keV), is 24%. The X-rays that interact with AAO can also generate electrons that reach the nano scintillator. The scintillation events of these electrons are seen as a low energy tail in the spectrum. In addition, it is found that all the X-rays that are absorbed in 300 nm thickness of the gold layer on the top of the zinc oxide nanowires can participate in the scintillation process with an efficiency of 6%. Hence, the scintillation detection efficiency of the whole detector for 9.8 keV X-ray energy is 30%. The simulation results from Geant4 and the experimental detected photons per MeV energy deposition are also used to extract the light yield of the zinc oxide nano scintillator. The results show that the light yield of the zinc oxide nanowires deposited by the electrochemical method is approximately the same as for single crystal zinc oxide scintillator (9000). Much better spatial resolution of this nano scintillator in comparison to the bulk ones is an advantage which candidates this nano scintillator for medical imaging applications.

Effect of Al2O3 insulator thickness on the structural integrity of amorphous indium-gallium-zinc-oxide based thin film transistors.

PubMed

Kim, Hak-Jun; Hwang, In-Ju; Kim, Youn-Jea

2014-12-01

The current transparent oxide semiconductors (TOSs) technology provides flexibility and high performance. In this study, multi-stack nano-layers of TOSs were designed for three-dimensional analysis of amorphous indium-gallium-zinc-oxide (a-IGZO) based thin film transistors (TFTs). In particular, the effects of torsional and compressive stresses on the nano-sized active layers such as the a-IGZO layer were investigated. Numerical simulations were carried out to investigate the structural integrity of a-IGZO based TFTs with three different thicknesses of the aluminum oxide (Al2O3) insulator (δ = 10, 20, and 30 nm), respectively, using a commercial code, COMSOL Multiphysics. The results are graphically depicted for operating conditions.

Low Temperature Film Growth of the Oxides of Zinc, Aluminum, and Vanadium (and Related Systems, Oxides of Gold and Germanium, Nitrides of Aluminum and Tungsten) by Reactive Sputter Deposition.

DTIC Science & Technology

1988-02-01

the optical behavior of the material in its preswitched, or A Perkin-Elmer Model 330 UV - Visible -IR double beam ,% spectrophotometer with a specular...S ~ * ." at.* U a * . a. *%~ ~9g 0 ~ --- a.. ’ a * ~ .r~vaa- *a,~ * ~ * ~****.,*a,* *** UV - Visible -IR Optical Behavior of Sputter Deposited Gee x...Films deposited in 0 to 60% Ar were nominally germania. However, transmission in the UV - visible , the strength of the 245nm defect center, the optical

Fabrication and RF characterization of zinc oxide based Film Bulk Acoustic Resonator

NASA Astrophysics Data System (ADS)

Patel, Raju; Bansal, Deepak; Agrawal, Vimal Kumar; Rangra, Kamaljit; Boolchandani, Dharmendar

2018-06-01

This work reports fabrication and characterization of Film Bulk Acoustic Resonator (FBAR) to improve the performance characteristics for RF filter and sensing application. Zinc oxide as a piezoelectric (PZE) material was deposited on an aluminum bottom electrode using an RF magnetron sputtering, at room temperature, and gold as top electrode for the resonator. Tetramethyl ammonium hydroxide (TMAH) setup was used for bulk silicon etching to make back side cavity to confine the acoustic signals. The transmission characteristics show that the FBARs have a central frequency at 1.77 GHz with a return loss of -10.7 dB.

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

NASA Astrophysics Data System (ADS)

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.

Zinc Supplementation Alters Plasma Aluminum and Selenium Status of Patients Undergoing Dialysis: A Pilot Study

PubMed Central

Guo, Chih-Hung; Chen, Pei-Chung; Hsu, Guoo-Shyng W.; Wang, Chia-Liang

2013-01-01

End stage renal disease patients undergoing long-term dialysis are at risk for abnormal concentrations of certain essential and non-essential trace metals and high oxidative stress. We evaluated the effects of zinc (Zn) supplementation on plasma aluminum (Al) and selenium (Se) concentrations and oxidative stress in chronic dialysis patients. Zn-deficient patients receiving continuous ambulatory peritoneal dialysis or hemodialysis were divided into two groups according to plasma Al concentrations (HA group, Al > 50 μg/L; and MA group, Al > 30 to ≤ 50 μg/L). All patients received daily oral Zn supplements for two months. Age- and gender-matched healthy individuals did not receive Zn supplement. Clinical variables were assessed before, at one month, and after the supplementation period. Compared with healthy subjects, patients had significantly lower baseline plasma Se concentrations and higher oxidative stress status. After two-month Zn treatment, these patients had higher plasma Zn and Se concentrations, reduced plasma Al concentrations and oxidative stress. Furthermore, increased plasma Zn concentrations were related to the concentrations of Al, Se, oxidative product malondialdehyde (MDA), and antioxidant enzyme superoxide dismutase activities. In conclusion, Zn supplementation ameliorates abnormally high plasma Al concentrations and oxidative stress and improves Se status in long-term dialysis patients. PMID:23609777

Large Scale Laser Crystallization of Solution-based Alumina-doped Zinc Oxide (AZO) Nanoinks for Highly Transparent Conductive Electrode

PubMed Central

Nian, Qiong; Callahan, Michael; Saei, Mojib; Look, David; Efstathiadis, Harry; Bailey, John; Cheng, Gary J.

2015-01-01

A new method combining aqueous solution printing with UV Laser crystallization (UVLC) and post annealing is developed to deposit highly transparent and conductive Aluminum doped Zinc Oxide (AZO) films. This technique is able to rapidly produce large area AZO films with better structural and optoelectronic properties than most high vacuum deposition, suggesting a potential large-scale manufacturing technique. The optoelectronic performance improvement attributes to UVLC and forming gas annealing (FMG) induced grain boundary density decrease and electron traps passivation at grain boundaries. The physical model and computational simulation developed in this work could be applied to thermal treatment of many other metal oxide films. PMID:26515670

Electro-thermal control of aluminum-doped zinc oxide/vanadium dioxide multilayered thin films for smart-device applications

PubMed Central

Skuza, J. R.; Scott, D. W.; Mundle, R. M.; Pradhan, A. K.

2016-01-01

We demonstrate the electro-thermal control of aluminum-doped zinc oxide (Al:ZnO) /vanadium dioxide (VO2) multilayered thin films, where the application of a small electric field enables precise control of the applied heat to the VO2 thin film to induce its semiconductor-metal transition (SMT). The transparent conducting oxide nature of the top Al:ZnO film can be tuned to facilitate the fine control of the SMT of the VO2 thin film and its associated properties. In addition, the Al:ZnO film provides a capping layer to the VO2 thin film, which inhibits oxidation to a more energetically favorable and stable V2O5 phase. It also decreases the SMT of the VO2 thin film by approximately 5–10 °C because of an additional stress induced on the VO2 thin film and/or an alteration of the oxygen vacancy concentration in the VO2 thin film. These results have significant impacts on technological applications for both passive and active devices by exploiting this near-room-temperature SMT. PMID:26884225

ALLOY COATINGS AND METHOD OF APPLYING

DOEpatents

Eubank, L.D.; Boller, E.R.

1958-08-26

A method for providing uranium articles with a pro tective coating by a single dip coating process is presented. The uranium article is dipped into a molten zinc bath containing a small percentage of aluminum. The resultant product is a uranium article covered with a thin undercoat consisting of a uranium-aluminum alloy with a small amount of zinc, and an outer layer consisting of zinc and aluminum. The article may be used as is, or aluminum sheathing may then be bonded to the aluminum zinc outer layer.

Synthesis and characterization of single-crystalline zinc tin oxide nanowires

NASA Astrophysics Data System (ADS)

Shi, Jen-Bin; Wu, Po-Feng; Lin, Hsien-Sheng; Lin, Ya-Ting; Lee, Hsuan-Wei; Kao, Chia-Tze; Liao, Wei-Hsiang; Young, San-Lin

2014-05-01

Crystalline zinc tin oxide (ZTO; zinc oxide with heavy tin doping of 33 at.%) nanowires were first synthesized using the electrodeposition and heat treatment method based on an anodic aluminum oxide (AAO) membrane, which has an average diameter of about 60 nm. According to the field emission scanning electron microscopy (FE-SEM) results, the synthesized ZTO nanowires are highly ordered and have high wire packing densities. The length of ZTO nanowires is about 4 μm, and the aspect ratio is around 67. ZTO nanowires with a Zn/(Zn + Sn) atomic ratio of 0.67 (approximately 2/3) were observed from an energy dispersive spectrometer (EDS). X-ray diffraction (XRD) and corresponding selected area electron diffraction (SAED) patterns demonstrated that the ZTO nanowire is hexagonal single-crystalline. The study of ultraviolet/visible/near-infrared (UV/Vis/NIR) absorption showed that the ZTO nanowire is a wide-band semiconductor with a band gap energy of 3.7 eV.

Synthesis and characterization of single-crystalline zinc tin oxide nanowires.

PubMed

Shi, Jen-Bin; Wu, Po-Feng; Lin, Hsien-Sheng; Lin, Ya-Ting; Lee, Hsuan-Wei; Kao, Chia-Tze; Liao, Wei-Hsiang; Young, San-Lin

2014-01-01

Crystalline zinc tin oxide (ZTO; zinc oxide with heavy tin doping of 33 at.%) nanowires were first synthesized using the electrodeposition and heat treatment method based on an anodic aluminum oxide (AAO) membrane, which has an average diameter of about 60 nm. According to the field emission scanning electron microscopy (FE-SEM) results, the synthesized ZTO nanowires are highly ordered and have high wire packing densities. The length of ZTO nanowires is about 4 μm, and the aspect ratio is around 67. ZTO nanowires with a Zn/(Zn + Sn) atomic ratio of 0.67 (approximately 2/3) were observed from an energy dispersive spectrometer (EDS). X-ray diffraction (XRD) and corresponding selected area electron diffraction (SAED) patterns demonstrated that the ZTO nanowire is hexagonal single-crystalline. The study of ultraviolet/visible/near-infrared (UV/Vis/NIR) absorption showed that the ZTO nanowire is a wide-band semiconductor with a band gap energy of 3.7 eV.

RECONDITIONING FUEL ELEMENTS

DOEpatents

Brandt, H.L.

1962-02-20

A process is given for decanning fuel elements that consist of a uranium core, an intermediate section either of bronze, silicon, Al-Si, and uranium silicide layers or of lead, Al-Si, and uranium silicide layers around said core, and an aluminum can bonded to said intermediate section. The aluminum can is dissolved in a solution of sodium hydroxide (9 to 20 wt%) and sodium nitrate (35 to 12 wt %), and the layers of the intermediate section are dissolved in a boiling sodium hydroxide solution of a minimum concentration of 50 wt%. (AEC) A method of selectively reducing plutonium oxides and the rare earth oxides but not uranium oxides is described which comprises placing the oxides in a molten solvent of zinc or cadmium and then adding metallic uranium as a reducing agent. (AEC)

Zinc-aluminum oxide solid solution nanosheets obtained by pyrolysis of layered double hydroxide as the photoanodes for dye-sensitized solar cells.

PubMed

Xu, Zhiyuan; Shi, Jingjing; Haroone, Muhammad Sohail; Chen, Wenpeng; Zheng, Shufang; Lu, Jun

2018-04-01

Due to the superiority of metal-doped ZnO compared to TiO 2 , the Zn-M (M = Al 3+ , Ga 3+ , Cr 3+ , Ti 4+ , Ce 4+ ) mixed metal oxide solid solutions have been extensively studied for photocatalytic and photovoltaic applications. In this work, a systematic research has proceeded for the preparation of a zinc-aluminum oxide semiconductor as a photoanode for the dye-sensitized solar cells (DSSCs) by a simple pyrolysis route with the Zn-Al layered double hydroxide (LDH) as a precursor. The Zn-Al oxide solid solution has been applied for DSSCs as an electron acceptor, which is used to study the influence of different Al content and sintering temperature on the device efficiency. Finally, the Zn-Al oxide solid solution with calcination temperature 600 °C and Al 27 at.% content exhibits the best performance. The photoelectric efficiency improved 100 times when the Al 3+ content decreased from 44 to 27 at.%. The Zn x Al y O solid solution show a reasonable efficiency as photoanode materials in DSSCs, with the best preliminary performance reported so far, and shows its potential application for the photovoltaic devices. Copyright © 2018 Elsevier Inc. All rights reserved.

Optimization of the optical and electrical properties of electron beam evaporated aluminum-doped zinc oxide films for opto-electronic applications

NASA Astrophysics Data System (ADS)

Ali, H. M.; Abd El-Raheem, M. M.; Megahed, N. M.; Mohamed, H. A.

2006-08-01

Aluminum-doped zinc oxide (AZO) thin films have been deposited by electron beam evaporation technique on glass substrates. The structural, electrical and optical properties of AZO films have been investigated as a function of annealing temperature. It was observed that the optical properties such as transmittance, reflectance, optical band gap and refractive index of AZO films were strongly affected by annealing temperature. The transmittance values of 84% in the visible region and 97% in the NIR region were obtained for AZO film annealed at 475 °C. The room temperature electrical resistivity of 4.6×10-3 Ω cm has been obtained at the same temperature of annealing. It was found that the calculated refractive index has been affected by the packing density of the thin films, whereas, the high annealing temperature gave rise to improve the homogeneity of the films. The single-oscillator model was used to analyze the optical parameters such as the oscillator and dispersion energies.

Developmental phytotoxicity of metal oxide nanoparticles to Arabidopsis thaliana.

PubMed

Lee, Chang Woo; Mahendra, Shaily; Zodrow, Katherine; Li, Dong; Tsai, Yu-Chang; Braam, Janet; Alvarez, Pedro J J

2010-03-01

Phytotoxicity is an important consideration to understand the potential environmental impacts of manufactured nanomaterials. Here, we report on the effects of four metal oxide nanoparticles, aluminum oxide (nAl(2)O(3)), silicon dioxide (nSiO(2)), magnetite (nFe(3)O(4)), and zinc oxide (nZnO), on the development of Arabidopsis thaliana (Mouse-ear cress). Three toxicity indicators (seed germination, root elongation, and number of leaves) were quantified following exposure to each nanoparticle at three concentrations: 400, 2,000, and 4,000 mg/L. Among these particles, nZnO was most phytotoxic, followed by nFe(3)O(4), nSiO(2), and nAl(2)O(3), which was not toxic. Consequently, nZnO was further studied to discern the importance of particle size and zinc dissolution as toxicity determinants. Soluble zinc concentrations in nanoparticle suspensions were 33-fold lower than the minimum inhibitory concentration of dissolved zinc salt (ZnCl(2)), indicating that zinc dissolution could not solely account for the observed toxicity. Inhibition of seed germination by ZnO depended on particle size, with nanoparticles exerting higher toxicity than larger (micron-sized) particles at equivalent concentrations. Overall, this study shows that direct exposure to nanoparticles significantly contributed to phytotoxicity and underscores the need for eco-responsible disposal of wastes and sludge containing metal oxide nanoparticles.

Evaluation of metallized paint coatings for composite spacecraft structures

NASA Technical Reports Server (NTRS)

Brzuskiewicz, John E.

1990-01-01

The extreme temperature excursions of composite spacecraft structures in LEO must be minimized through the use of thermal-control coatings. Attention is presently given to tests of silicone resin coatings which were pigmented with either leafing aluminum or combinations of leafing aluminum with silicate-treated zinc oxide pigment. Atomic oxygen, UV/vacuum, and outgassing screening tests were conducted on several such coating formulations in order to characterize the performance characteristics of this coating concept. Performance was found to depend on pigment volume concentration.

Use of New Industrial Coatings for the U.S. Navy Waterfront Structures

DTIC Science & Technology

2008-12-01

utilized as a coating for the interior and exterior of piping systems, which either are located in harsh environments or are transporting substances with...typical application process, a separate set of test Table 7. MCU Coating Systems (SSPC SP 10 Surfaces) (5). SystelD CoatiIli System A Zinc -rich urethane...urethane/MID & AI-filled Urethane/MIO-filled urethane 315/315/314 336/336/336 340/340/336 ~ Micaceous iron oxide. \\) Aluminum. C Zinc . 12 as well as an

Simulation, optimization and testing of a novel high spatial resolution X-ray imager based on Zinc Oxide nanowires in Anodic Aluminium Oxide membrane using Geant4

NASA Astrophysics Data System (ADS)

Esfandi, F.; Saramad, S.

2015-07-01

In this work, a new generation of scintillator based X-ray imagers based on ZnO nanowires in Anodized Aluminum Oxide (AAO) nanoporous template is characterized. The optical response of ordered ZnO nanowire arrays in porous AAO template under low energy X-ray illumination is simulated by the Geant4 Monte Carlo code and compared with experimental results. The results show that for 10 keV X-ray photons, by considering the light guiding properties of zinc oxide inside the AAO template and suitable selection of detector thickness and pore diameter, the spatial resolution less than one micrometer and the detector detection efficiency of 66% are accessible. This novel nano scintillator detector can have many advantages for medical applications in the future.

I-III-VI.sub.2 based solar cell utilizing the structure CuInGaSe.sub.2 CdZnS/ZnO

DOEpatents

Chen, Wen S.; Stewart, John M.

1992-01-07

A thin film I-III-VI.sub.2 based solar cell having a first layer of copper indium gallium selenide, a second layer of cadmium zinc sulfide, a double layer of zinc oxide, and a metallization structure comprised of a layer of nickel covered by a layer of aluminum. An optional antireflective coating may be placed on said metallization structure. The cadmium zinc sulfide layer is deposited by means of an aqueous solution growth deposition process and may actually consist of two layers: a low zinc content layer and a high zinc content layer. Photovoltaic efficiencies of 12.5% at Air Mass 1.5 illumination conditions and 10.4% under AMO illumination can be achieved.

Hydrothermal synthesis and characterization of hybrid Al/ZnO-GO composite for significant photodegrdation of dyes

NASA Astrophysics Data System (ADS)

Lellala, Kashinath; Namratha, K.; Sudhakar, K.; Byrappa, K.

2016-05-01

In the present work, undoped and doped Aluminum/Zinc Oxide - graphene oxide (Al/ZnO-GO) nanocomposite have been successfully synthesized by hydrothermal method from zinc acetate and aluminum nitrate solutions without using of any surfactant/stabilizing agents. The results show that the composites of GO nanosheets are decorated densely by Al/ZnO nanoparticles, which displays a good morphology and blend between GO and Al/ZnO. Hybrid composites exhibit an enhanced photocatalytic performance in reduction of dyes under UV-Vis radiation better than bare ZnO-GO and GO for methylene blue dye. The hydrothermal method leads to particles with a higher crystalline due to ambient temperature of the reaction and autogenously pressure conditions, which alters the phases and crystallizations of the nanocomposite. The optical band gap is narrowed to lower energy values due to controlled addition of aluminum and GO in the composite. The improved optical property in Al-doped ZnO flower decorated on GO can be attributed to the decrease in oxygen deficiency after Al doping. XRD, FTIR, UV-Vis spectroscopy, Raman, and Field Emission Scanning Electron Microscopy characterized the effects of Al doping on the structural characteristics and optical properties on the ZnO-GO.

Hydrothermal synthesis and characterization of hybrid Al/ZnO-GO composite for significant photodegrdation of dyes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lellala, Kashinath; Namratha, K.; Byrappa, K., E-mail: kashinathlellala@gmail.com, E-mail: kbyrappa@gmail.com

In the present work, undoped and doped Aluminum/Zinc Oxide - graphene oxide (Al/ZnO-GO) nanocomposite have been successfully synthesized by hydrothermal method from zinc acetate and aluminum nitrate solutions without using of any surfactant/stabilizing agents. The results show that the composites of GO nanosheets are decorated densely by Al/ZnO nanoparticles, which displays a good morphology and blend between GO and Al/ZnO. Hybrid composites exhibit an enhanced photocatalytic performance in reduction of dyes under UV-Vis radiation better than bare ZnO-GO and GO for methylene blue dye. The hydrothermal method leads to particles with a higher crystalline due to ambient temperature of themore » reaction and autogenously pressure conditions, which alters the phases and crystallizations of the nanocomposite. The optical band gap is narrowed to lower energy values due to controlled addition of aluminum and GO in the composite. The improved optical property in Al-doped ZnO flower decorated on GO can be attributed to the decrease in oxygen deficiency after Al doping. XRD, FTIR, UV-Vis spectroscopy, Raman, and Field Emission Scanning Electron Microscopy characterized the effects of Al doping on the structural characteristics and optical properties on the ZnO-GO.« less

Influence of annealing temperature on optical properties of Al doped ZnO nanoparticles via sol-gel methods

NASA Astrophysics Data System (ADS)

Rashid, Affa Rozana Abd; Hazwani, Tuan Nur; Mukhtar, Wan Maisarah; Taib, Nur Athirah Mohd

2018-06-01

Zinc oxide (ZnO) thin films have become technologically important materials due to their wide range of electrical and optical properties. The characteristics can be further adjusted by adequate doping processes. The effect of dopant concentration of Al, heating treatment and annealing in reducing atmosphere on the optical properties of the thin films is discussed. Undoped and aluminum-doped zinc oxide (AZO) thin films are prepared by the sol-gel method. Zinc acetate dihydrate, 2-methoxyethanol and monoethanolamine are used as precursor, solvent and stabilizer. In the case of AZO, aluminum nitrate nanohydrate is added to the precursor solution with an atomic percentage equal to 0 %, 1 %, 2 % and 3 % of Al. The multi thin layers are transformed into ZnO upon annealing at 450 °C and 500 °C. The optical properties such as transmittance, absorbance, band gap and refractive index of the thin films have been investigated by using UV-Visible Spectroscopy (UV-Vis). The results show that the effect of aluminium dopant concentration on the optical properties is depend on the post-heat treatment of the films. By doping with Al, the transmittance spectra in visible range increased and widen the band gap of ZnO which might due to Burstein-moss effects.

Understanding and Quantifying the Reactivity of Energetic NanoParticles and NanoComposites

DTIC Science & Technology

2015-01-05

Aerosol Synthesis and Reactivity of Thin Oxide Shell Aluminum Nanoparticles via Fluorocarboxylic Acid Functional Coating, Particle & Particle...Received Paper 3.00 9.00 8.00 7.00 6.00 5.00 4.00 X. Ma and M.R. Zachariah. " Oxidation Anisotropy and Size Dependent Reaction Kinetics of Zinc ...in the reaction. Experiments also conducted for neat Al, CuO, Fe2O3 and ZnO powders show that the oxygen are produced by decomposition of oxidizer

Corrosion-resistant uranium

DOEpatents

Hovis, V.M. Jr.; Pullen, W.C.; Kollie, T.G.; Bell, R.T.

1981-10-21

The present invention is directed to the protecting of uranium and uranium alloy articles from corrosion by providing the surfaces of the articles with a layer of an ion-plated metal selected from aluminum and zinc to a thickness of at least 60 microinches and then converting at least the outer surface of the ion-plated layer of aluminum or zinc to aluminum chromate or zinc chromate. This conversion of the aluminum or zinc to the chromate form considerably enhances the corrosion resistance of the ion plating so as to effectively protect the coated article from corrosion.

Corrosion-resistant uranium

DOEpatents

Hovis, Jr., Victor M.; Pullen, William C.; Kollie, Thomas G.; Bell, Richard T.

1983-01-01

The present invention is directed to the protecting of uranium and uranium alloy articles from corrosion by providing the surfaces of the articles with a layer of an ion-plated metal selected from aluminum and zinc to a thickness of at least 60 microinches and then converting at least the outer surface of the ion-plated layer of aluminum or zinc to aluminum chromate or zinc chromate. This conversion of the aluminum or zinc to the chromate form considerably enhances the corrosion resistance of the ion plating so as to effectively protect the coated article from corrosion.

Quadrupolar magic angle spinning NMR spectra fitted using the Pearson IV function.

PubMed

Mironenko, Roman M; Belskaya, Olga B; Talsi, Valentin P; Likholobov, Vladimir A

2014-01-01

The Pearson IV function was used to fit the asymmetric solid-state (27)Al NMR spectra of alumina based catalysts. A high convergence (correlation coefficient is no less than 0.997) between experimental and simulated spectra was achieved. The decomposition of the (27)Al NMR spectra of zinc/aluminum mixed oxides with different Zn/Al molar ratio revealed an increased fraction (6-9%) of pentacoordinated aluminum atoms in these oxides as compared to γ-Al2O3. As the Zn/Al ratio is raised, the fraction of [AlO6] octahedral units decreases, while the fraction of [AlO4] tetrahedra increases. Copyright © 2014 Elsevier Inc. All rights reserved.

Effect of Zinc Oxide Doping on Electroluminescence and Electrical Behavior of Metalloporphyrins-Doped Samarium Complex

NASA Astrophysics Data System (ADS)

Janghouri, Mohammad; Amini, Mostafa M.

2018-02-01

Samarium complex [(Sm(III)] as a new host material was used for preparation of red organic light-emitting diodes (OLEDs). Devices with configurations of indium-doped tin oxide (ITO)/poly(3,4-ethylenedioxythiophene):(poly(styrenesulfonate) (PEDOT:PSS (50 nm)/polyvinyl carbazole (PVK):[zinc oxide (ZnO)] (50 nm)/[(Sm(III)]:[zinc(II) 2,3-tetrakis(dihydroxyphenyl)-porphyrin and Pt(II) 2,3-dimethoxyporphyrin] (60 nm)/2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) (15 nm)/Al (150 nm) have been fabricated and investigated. An electroplex occurring at the (PVK/Sm: Pt(II) 2,3-dimethoxyporphyrin) interface has been suggested when ZnO nanoparticles were doped in PVK. OLED studies have revealed that the photophysical characteristics and electrical behavior of devices with ZnO nanoparticles are much better than those of devices with pure PVK. The efficiency of devices based on [(Sm(III)] was superior than that of known aluminum tris(8-hydroxyquinoline) (Alq3) and also our earlier reports on red OLEDs under the same conditions.

Facile Route to Rare Heterobimetallic Aluminum-Copper and Aluminum-Zinc Selenide Clusters.

PubMed

Li, Bin; Li, Jiancheng; Liu, Rui; Zhu, Hongping; Roesky, Herbert W

2017-03-20

Heterobimetallic aluminum-copper and aluminum-zinc clusters were prepared from the reaction of LAl(SeH) 2 [1; L = HC(CMeNAr) 2 and Ar = 2,6-iPr 2 C 6 H 3 ] with (MesCu) 4 and ZnEt 2 , respectively. The resulting clusters with the core structures of Al 2 Se 4 Cu 4 and Al 2 Se 4 Zn 3 exhibit unique metal-organic frameworks. This is a novel pathway for the synthesis of aluminum-copper and aluminum-zinc selenides. The products have been characterized by spectroscopic methods and single-crystal X-ray structural characterization.

High-Performance Flexible Perovskite Solar Cells on Ultrathin Glass: Implications of the TCO

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dou, Benjia; Miller, Elisa M.; Christians, Jeffrey A.

For halide perovskite solar cells (PSCs) to fulfill their vast potential for combining low-cost, high efficiency, and high throughput production they must be scaled using a truly transformative method, such as roll-to-roll processing. Bringing this reality closer to fruition, the present work demonstrates flexible perovskite solar cells with 18.1% power conversion efficiency on flexible Willow Glass substrates. Here, we highlight the importance of the transparent conductive oxide (TCO) layers on device performance by studying various TCOs. And while tin-doped indium oxide (ITO) and indium zinc oxide (IZO) based PSC devices demonstrate high photovoltaic performances, aluminum-doped zinc oxide (AZO) based devicesmore » underperformed in all device parameters. Analysis of X-ray photoemission spectroscopy data shows that the stoichiometry of the perovskite film surface changes dramatically when it is fabricated on AZO, demonstrating the importance of the substrate in perovskite film formation.« less

High-Performance Flexible Perovskite Solar Cells on Ultrathin Glass: Implications of the TCO

DOE PAGES

Dou, Benjia; Miller, Elisa M.; Christians, Jeffrey A.; ...

2017-09-27

For halide perovskite solar cells (PSCs) to fulfill their vast potential for combining low-cost, high efficiency, and high throughput production they must be scaled using a truly transformative method, such as roll-to-roll processing. Bringing this reality closer to fruition, the present work demonstrates flexible perovskite solar cells with 18.1% power conversion efficiency on flexible Willow Glass substrates. Here, we highlight the importance of the transparent conductive oxide (TCO) layers on device performance by studying various TCOs. And while tin-doped indium oxide (ITO) and indium zinc oxide (IZO) based PSC devices demonstrate high photovoltaic performances, aluminum-doped zinc oxide (AZO) based devicesmore » underperformed in all device parameters. Analysis of X-ray photoemission spectroscopy data shows that the stoichiometry of the perovskite film surface changes dramatically when it is fabricated on AZO, demonstrating the importance of the substrate in perovskite film formation.« less

Optical properties of aluminum-doped zinc oxide films deposited by direct-current pulse magnetron reactive sputtering

NASA Astrophysics Data System (ADS)

Gao, Xiao-Yong; Chen, Chao; Zhang, Sa

2014-03-01

A series of <103>-oriented aluminum-doped zinc oxide (AZO) films were deposited on glass substrates via direct-current pulse magnetron reactive sputtering at different O2-to-Ar gas flow ratios (GFRs). The optical properties of the films were characterized using the fitted optical constants in the general oscillator model (which contains two Psemi-Tri oscillators) through the use of measured ellipsometric parameters. The refractive index dispersion data below the interband absorption edge were analyzed using a single-oscillator model. The fitted optical energy gap obtained using the single-oscillator model clearly shows a blue shift, followed by a red shift, as the GFR increases from 0.9/18 to 2.1/18. This shift can be attributed to the change in the free electron concentration of the film, which is closely related to the film stress. In addition, the fitted β value indicates that the AZO film falls under the ionic class. The photoluminescence spectrum indicates a photoluminescence mechanism of the direct and wide energy gap semiconductor.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sweet, William J.; Oldham, Christopher J.; Parsons, Gregory N., E-mail: parsons@ncsu.edu

Flexible electronics and wearable technology represent a novel and growing market for next generation devices. In this work, the authors deposit conductive zinc oxide films by atomic layer deposition onto nylon-6 nonwoven fiber mats and spun-cast films, and quantify the impact that deposition temperature, coating thickness, and aluminum doping have on the conductivity of the coated substrates. The authors produce aluminum doped zinc oxide (AZO) coated fibers with conductivity of 230 S/cm, which is ∼6× more conductive than ZnO coated fibers. Furthermore, the authors demonstrate AZO coated fibers maintain 62% of their conductivity after being bent around a 3 mm radius cylinder.more » As an example application, the authors fabricate an “all-fiber” pressure sensor using AZO coated nylon-6 electrodes. The sensor signal scales exponentially under small applied force (<50 g/cm{sup 2}), yielding a ∼10{sup 6}× current change under 200 g/cm{sup 2}. This lightweight, flexible, and breathable touch/force sensor could function, for example, as an electronically active nonwoven for personal or engineered system analysis and diagnostics.« less

Investigation of the role of α-lipoic acid on fatty acids profile, some minerals (zinc, copper, iron) and antioxidant activity against aluminum-induced oxidative stress in the liver of male rats.

PubMed

Sahin, Zafer; Ozkaya, Ahmet; Yilmaz, Okkes; Yuce, Abdurrauf; Gunes, Mehmet

2017-07-26

We have investigated the effects of α-lipoic acid (LA), a powerful antioxidant, on the fatty acid (FA) profiles, aluminum accumulation, antioxidant activity and some minerals such as zinc, copper and iron against aluminum chloride (AlCl3)-induced oxidative stress in rat liver. Twenty-eight male Wistar rats were divided into four groups as control, LA, AlCl3 and LA+AlCl3. For 30 days, LA was intraperitoneally administrated (50 mg/kg) and AlCl3 was given via orogastric gavage (1600 ppm) every other day. AlCl3-treated animals exhibited higher hepatic malondialdehyde concentration and lower glutathione peroxidase and catalase activity, whereas these alterations were restored by the LA supplementation. Total saturated FA of the AlCl3-treated group was higher than the LA supplementation groups. Moreover, total unsaturated FA level of the LA+AlCl3 group was higher than the AlCl3-treated group. Hepatic zinc level of the AlCl3-treated group was lower than the control group, whereas it was higher in the LA and the LA+AlCl3 groups. Hepatic copper levels did not significantly change in the experimental groups. Iron level was lower in the LA and LA+AlCl3 groups compared with the AlCl3-treated group. Moreover, the liver Al concentration was found to be lower in the LA and LA+AlCl3 groups compared to the AlCl3 group. These results indicate that AlCl3 treatment can induce oxidative stress in the liver. LA supplementation has a beneficial effect on the AlCl3-induced alterations such as high lipid peroxidation, Al accumulation, FA profile ratios and mineral concentrations.

Inert anode containing oxides of nickel, iron and zinc useful for the electrolytic production of metals

DOEpatents

Ray, Siba P.; Weirauch, Jr., Douglas A.; Liu, Xinghua

2002-01-01

An inert anode for the electrolytic production of metals such as aluminum is disclosed. The inert anode includes a ceramic oxide material preferably made from NiO, Fe.sub.2 O.sub.3 and ZnO. The inert anode composition may comprise the following mole fractions of NiO, Fe.sub.2 O.sub.3 and ZnO: 0.2 to 0.99 NiO; 0.0001 to 0.8 Fe.sub.2 O.sub.3 ; and 0.0001 to 0.3 ZnO. The inert anode may optionally include other oxides and/or at least one metal phase, such as Cu, Ag, Pd, Pt, Au, Rh, Ru, Ir and/or Os. The Ni--Fe--Co--O ceramic material exhibits very low solubility in Hall cell baths used to produce aluminum.

Structure and Corrosion Behavior of Arc-Sprayed Zn-Al Coatings on Ductile Iron Substrate

NASA Astrophysics Data System (ADS)

Bonabi, Salar Fatoureh; Ashrafizadeh, Fakhreddin; Sanati, Alireza; Nahvi, Saied Mehran

2018-02-01

In this research, four coatings including pure zinc, pure aluminum, a double-layered coating of zinc and aluminum, and a coating produced by simultaneous deposition of zinc and aluminum were deposited on a cast iron substrate using electric arc-spraying technique. The coatings were characterized by XRD, SEM and EDS map and spot analyses. Adhesion strength of the coatings was evaluated by three-point bending tests, where double-layered coating indicated the lowest bending angle among the specimens, with detection of cracks at the coating-substrate interface. Coatings produced by simultaneous deposition of zinc and aluminum possessed a relatively uniform distribution of both metals. In order to evaluate the corrosion behavior of the coatings, cyclic polarization and salt spray tests were conducted. Accordingly, pure aluminum coating showed susceptibility to pitting corrosion and other coatings underwent uniform corrosion. For double-layered coating, SEM micrographs revealed zinc corrosion products as flaky particles in the pores formed by pitting on the surface, an indication of penetration of corrosion products from the lower layer (zinc) to the top layer (aluminum). All coatings experienced higher negative corrosion potentials than the iron substrate, indicative of their sacrificial behavior.

Biodiscovery of Aluminum Binding Peptides

DTIC Science & Technology

2013-08-01

et al., "Biomimetic synthesis and patterning of silver nanoparticles ," Nat. Mater. 1(3), 169-172 (2002). [5] Van Dorst, B., et al., "Phage display...34Sequestration of zinc oxide by fimbrial designer chelators," Appl. Environ. Microbiol. 66(1), 10-14 (2000). [26] Hnilova, M., et al., "Peptide-directed co...biomaterial synthesis . Peptides have been developed that bind to a variety of inorganic materials, including metals1-6, oxides7, 8, alloys9, metal salts10

Rapid Thermal Annealing for Solution Synthesis of Transparent Conducting Aluminum Zinc Oxide Thin Films

NASA Astrophysics Data System (ADS)

Ullah, Sana; De Matteis, Fabio; Davoli, Ivan

2017-11-01

Transparent conducting oxide films with optimized dopant molar ratio have been prepared with limited pre- and postdeposition annealing duration of 10 min. Multiple aluminum zinc oxide (AZO) layers were spin-coated on ordinary glass substrates. The predeposition consolidation temperature and dopant molar ratio were optimized for electrical conductivity and optical transparency. Next, a group of films were deposited on Corning glass substrates from precursor solutions with the optimized dopant ratio, followed by postdeposition rapid thermal annealing (RTA) at different temperatures and in controlled environments. The lowest resistivity of 10.1 × 10-3 Ω cm was obtained for films receiving RTA at 600°C for 10 min each in vacuum then in N2-5%H2 environment, while resistivity of 20.3 × 10-3 Ω cm was obtained for films subjected to RTA directly in N2-5%H2. Optical measurements revealed average total transmittance of about 85% in the visible region. A direct allowed transition bandgap was determined based on the absorption edge with a value slightly above 3.0 eV, within the typical range for semiconductors. RTA resulted in desorption of oxygen with enhanced carrier concentration and crystallinity, which increased the carrier mobility with decreased bulk resistivity while maintaining the required optical transparency.

Reconnaissance for determining effects of land use and surficial geology on concentrations of selected elements on streambed materials from the coal-mining region, southwestern Indiana, October 1979 to March 1980

USGS Publications Warehouse

Wilber, W.G.; Boje, Rita R.

1982-01-01

Streambed materials were collected in October 1979 from 69 watersheds in Southwest Indiana having predominantly forested, agricultural, reclaimed, and unreclaimed mined land use to determine whether concentrations of sorbed and acid-soluble metals and trace elements were affected by land use and surficial geology. Analysis of variance indicated that 10% or more of the total variation in aluminum, arsenic, cobalt, iron, nickel, selenium, and zinc concentrations on streambed materials was accounted for by differences in land use. Concentrations of aluminum, cobalt, iron, nickel, selenium, and zinc on streambed materials smaller than 0.062-millimeter from mined watersheds were significantly greater than the concentrations of these elements on streambed materials from agricultural and forested watersheds. The greater concentrations of these elements on streambed materials are due to (1) their concentrations in mine drainage and their subsequent absorption and (or) copecipitation with the oxides and hydroxides of aluminum and iron and (2) their concentrations in coal and pyritic material in streambed materials. (USGS)

40 CFR 467.15 - Pretreatment standards for existing sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... aluminum rolled with neat oils Chromium 0.036 0.015 Cyanide 0.024 0.010 Zinc 0.119 0.050 TTO 0.057 Oil and... off-lbs) of aluminum rolled with neat oils Chromium 0.025 0.010 Cyanide 0.016 0.007 Zinc 0.081 0.034... (lb/million off-lbs) of aluminum cast Chromium 0.00086 0.00035 Cyanide 0.00057 0.00024 Zinc 0.0029 0...

Questa baseline and pre-mining ground-water quality investigation. 12. Geochemical and reactive-transport modeling based on tracer injection-synoptic sampling studies for the Red River, New Mexico, 2001-2002

USGS Publications Warehouse

Ball, James W.; Runkel, Robert L.; Nordstrom, D. Kirk

2005-01-01

Reactive-transport processes in the Red River, downstream from the town of Red River in north-central New Mexico, were simulated using the OTEQ reactive-transport model. The simulations were calibrated using physical and chemical data from synoptic studies conducted during low-flow conditions in August 2001 and during March/April 2002. Discharge over the 20-km reach from the town of Red River to the USGS streamflow-gaging station near the town of Questa ranged from 395 to 1,180 L/s during the 2001 tracer and from 234 to 421 L/s during the 2002 tracer. The pH of the Red River ranged from 7.4 to 8.5 during the 2001 tracer and from 7.1 to 8.7 during the 2002 tracer, and seep and tributary samples had pH values of 2.8 to 9.0 during the 2001 tracer and 3.8 to 7.2 during the 2002 tracer. Mass-loading calculations allowed identification of several specific locations where elevated concentrations of potential contaminants entered the Red River . These locations, characterized by features on the north side of the Red River that are known to be sources of low-pH water containing elevated metal and sulfate concentrations, are: the initial 2.4 km of the study reach, including Bitter Creek, the stream section from 6.2 to 7.8 km, encompassing La Bobita well and the Hansen debris fan, Sulphur Gulch, at about 10.5 km, the area near Portal Springs, from 12.2 to 12.6 km, and the largest contributors of mass loading, the 13.7 to 13.9 km stream section near Cabin Springs and the 14.7 to 17.5 km stream section from Shaft Spring to Thunder Bridge, Goathill Gulch, and Capulin Canyon. Speciation and saturation index calculations indicated that although solubility limits the concentration of aluminum above pH 5.0, at pH values above 7 and aluminum concentrations below 0.3 mg/L inorganic speciation and mineral solubility controls no longer dominate and aluminum-organic complexing may occur. The August 2001 reactive-transport simulations included dissolved iron(II) oxidation, constrained using measured concentrations of dissolved iron(II) and dissolved iron(total). Both simulations included precipitation of amorphous Al(OH)3 and hydrous ferric oxide as Fe(OH)3, and sorption of copper and zinc to the precipitated hydrous ferric oxide. Simulations revealed that hydrogen, iron, aluminum, copper, and zinc were non-conservative and that mineral precipitation can account for iron and aluminum concentrations. Copper and zinc concentrations can be accounted for by simulating their sorption to hydrous ferric oxide forming in the water column of the Red River , although hydrous manganese oxides also may be important sorption substrates.

Effect of growth time to the properties of Al-doped ZnO nanorod arrays

NASA Astrophysics Data System (ADS)

Ismail, A. S.; Mamat, M. H.; Malek, M. F.; Saidi, S. A.; Yusoff, M. M.; Mohamed, R.; Sin, N. D. Md; Suriani, A. B.; Rusop, M.

2018-05-01

Aluminum (Al)-doped zinc oxide (ZnO) nanorod array films were successfully deposited at different growth time on zinc oxide (ZnO) seed layer coated glass substrate using sol-gel immersion method. The morphology images of the films showed that the thicknesses of the films were increased parallel with the increment of growth period. The surface topology of the films displayed an increment of roughness as the growth period increased. Optical properties of the samples exposed that the percentage of transmittances reduced at higher growth time. Besides, the Urbach energy of the films slightly increased as the immersion time increased. The current-voltage (I-V) measurement indicated that the resistance increased as the immersion time increased owing to the appearance of intrinsic layer on top of the nanorods.

REGENERATION OF REACTOR FUEL ELEMENTS

DOEpatents

Lyon, W.L.

1960-04-01

A process is described for concentrating uranium and/or plutonium metal in aluminum alloys in which the actinide content was partially consumed by neutron bombardinent. Two embodiments are claimed: Either the alloy is heated, together with zinc chloride to at least 1000 deg C whereby some aluminum, in the form of aluminum chloride, and any zinc formed volatilize; or else aluminum fluoride is added and reacted at 800 to 1000 deg O and substmospheric pressure whereby pant of the aluminum volatilizes and aluminum subfluoride.

High Transparent Conductive Aluminum-Doped Zinc Oxide Thin Films by Reactive Co-Sputtering (Postprint)

DTIC Science & Technology

2016-03-30

wavelength where n = k) is 1605 nm from the film (f). Figure 1 XRD patterns of the AZO films on quartz substrate Figure 2 UV-Vis-NIR...71.6 1605 9.87 x10 -4 Figure 3 Refractive index n (left) and extinction coefficient k of (right) the AZO films. 4. Conclusions AZO films were

Optical and structural properties of Al-doped ZnO thin films by sol gel process.

PubMed

Jun, Min-Chul; Koh, Jung-Hyuk

2013-05-01

Transparent conducting oxide (TCO) materials with high transmittance and good electrical conductivity have been attracted much attention due to the development of electronic display and devices such as organic light emitting diodes (OLEDs), and dye-sensitized solar cells (DSSCs). Aluminum doped zinc oxide thin films (AZO) have been well known for their use as TCO materials due to its stability, cost-effectiveness, good optical transmittance and electrical properties. Especially, AZO thin film, which have low resistivity of 2-4 x 10(-4) omega x cm which is similar to that of ITO films with wide band gap semiconductors. The AZO thin films were deposited on glass substrates by sol-gel spin-coating process. As a starting material, zinc acetate dihydrate (Zn(CH3COO)2 x 2H2O) and aluminum chloride hexahydrate (AlCl3 6H2O) were used. 2-methoxyethanol and monoethanolamine (MEA) were used as solvent and stabilizer, respectively. After deposited, the films were preheated at 300 degrees C on a hotplate and post-heated at 650 degrees C for 1.5 hrs in the furnace. We have studied the structural and optical properties as a function of Al concentration (0-2.5 mol.%).

Fabrication and characteristics of high-performance and high-stability aluminum-doped zinc oxide thin-film transistors

NASA Astrophysics Data System (ADS)

Shan, Dongfang; Han, Dedong; Huang, Fuqing; Tian, Yu; Zhang, Suoming; Qi, Lin; Cong, Yingying; Zhang, Shengdong; Zhang, Xing; Wang, Yi

2014-01-01

Fully transparent aluminum-doped zinc oxide (AZO) thin-film transistors (TFTs) were successfully fabricated on glass substrates at room temperature. Superior properties, such as a high saturation mobility of 59.3 cm2 V-1 s-1, a positive threshold voltage of 1.3 V, a steep subthreshold swing of 122.9 mV/dec, an off-state current on the order of 10-12 A, and an on/off ratio of 2.7 × 108, were obtained. The electrical properties of the AZO TFTs were successively studied within a period of six months. Small property degenerations could be observed from the test results obtained within the study period, which proved the high-performance and high-stability characteristics of AZO TFTs. Furthermore, hysteresis loop scanning of AZO TFTs was performed, and a small hysteresis could be detected in the scanning curves, which suggested the superior properties of a dielectric and a channel-insulator interface. Lastly, we succeeded in manufacturing an organic LED (OLED) flat panel display panel driven by AZO TFTs and obtained an excellent display effect from it. We believe that AZO TFTs are a promising candidate successor to Si-based TFTs in next-generation flat panel displays.

Selective oxidation of dual phase steel after annealing at different dew points

NASA Astrophysics Data System (ADS)

Lins, Vanessa de Freitas Cunha; Madeira, Laureanny; Vilela, Jose Mario Carneiro; Andrade, Margareth Spangler; Buono, Vicente Tadeu Lopes; Guimarães, Juliana Porto; Alvarenga, Evandro de Azevedo

2011-04-01

Hot galvanized steels have been extensively used in the automotive industry. Selective oxidation on the steel surface affects the wettability of zinc on steel and the grain orientation of inhibition layer (Fe-Al-Zn alloy) and reduces the iron diffusion to the zinc layer. The aim of this work is to identify and quantify selective oxidation on the surface of a dual phase steel, and an experimental steel with a lower content of manganese, annealed at different dew points. The techniques employed were atomic force microscopy, X-ray photoelectron spectroscopy, and glow discharge optical emission spectroscopy. External selective oxidation was observed for phosphorus on steel surface annealed at 0 °C dp, and for manganese, silicon, and aluminum at a lower dew point. The concentration of manganese was higher on the dual phase steel surface than on the surface of the experimental steel. The concentration of molybdenum on the surface of both steels increased as the depth increased.

Radiopacity of portland cement associated with different radiopacifying agents.

PubMed

Húngaro Duarte, Marco Antonio; de Oliveira El Kadre, Guâniara D'arc; Vivan, Rodrigo Ricci; Guerreiro Tanomaru, Juliane Maria; Tanomaru Filho, Mário; de Moraes, Ivaldo Gomes

2009-05-01

This study evaluated the radiopacity of Portland cement associated with the following radiopacifying agents: bismuth oxide, zinc oxide, lead oxide, bismuth subnitrate, bismuth carbonate, barium sulfate, iodoform, calcium tungstate, and zirconium oxide. A ratio of 20% radiopacifier and 80% white Portland cement by weight was used for analysis. Pure Portland cement and dentin served as controls. Cement/radiopacifier and dentin disc-shaped specimens were fabricated, and radiopacity testing was performed according to the ISO 6876/2001 standard for dental root sealing materials. Using Insight occlusal films, the specimens were radiographed near to a graduated aluminum stepwedge varying from 2 to 16 mm in thickness. The radiographs were digitized and radiopacity compared with the aluminum stepwedge using Digora software (Orion Corporation Soredex, Helsinki, Finland). The radiographic density data were converted into mmAl and analyzed statistically by analysis of variance and Tukey-Kramer test (alpha = 0.05). The radiopacity of pure Portland cement was significantly lower (p < 0.05) than that of dentin, whereas all cement/radiopacifier mixtures were significantly more radiopaque than dentin and Portland cement alone (p < 0.05). Portland cement/bismuth oxide and Portland cement/lead oxide presented the highest radiopacity values and differed significantly from the other materials (p < 0.05), whereas Portland cement/zinc oxide presented the lowest radiopacity values of all mixtures (p < 0.05). All tested substances presented higher radiopacity than that of dentin and may potentially be added to the Portland cement as radiopacifying agents. However, the possible interference of the radiopacifiers with the setting chemistry, biocompatibility, and physical properties of the Portland cement should be further investigated before any clinical recommendation can be done.

78 FR 57630 - Information Collection Request Submitted to OMB for Review and Approval; Comment Request; NSPS...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-09-19

..., Primary Copper Smelters, Primary Zinc Smelters, Primary Lead Smelters, Primary Aluminum Reduction Plants...), Primary Copper Smelters (40 CFR Part 60, Subpart P), Primary Zinc Smelters (40 CFR Part 60, Subpart Q... zinc smelters, primary lead smelters, primary aluminum reduction plants, and ferroalloy production...

Effect of commercial metals (Al, Cu, carbon steel, and Zn) on the oxidation of soy-biodiesel

NASA Astrophysics Data System (ADS)

Díaz-Ballote, L.; Castillo-Atoche, A.; Maldonado, L.; Ruiz-Gómez, M. A.; Hernández, E.

2016-09-01

The effect of aluminum, copper, low carbon steel and zinc on the oxidation of biodiesel derived from soybean oil is studied using residual mass curves from thermogravimetry. Biodiesel is oxidized in the presence and absence of each metal in static conditions and exposed to ambient air. Oxidized biodiesel parameters are confirmed by viscosity measurements, nuclear magnetic resonance and Fourier transform infrared spectroscopy. The results showed that the metals do not negatively influence the oxidative stability of biodiesel and it can even be considered that they slightly inhibit the oxidation process. This behavior was ascribed to a depletion of dissolved oxygen in biodiesel due to oxidation of the metal and the low solubility of oxygen at high temperature.

Atomic layer deposition of nanoporous biomaterials.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Narayan, R. J.; Adiga, S. P.; Pellin, M. J.

2010-03-01

Due to its chemical stability, uniform pore size, and high pore density, nanoporous alumina is being investigated for use in biosensing, drug delivery, hemodialysis, and other medical applications. In recent work, we have examined the use of atomic layer deposition for coating the surfaces of nanoporous alumina membranes. Zinc oxide coatings were deposited on nanoporous alumina membranes using atomic layer deposition. The zinc oxide-coated nanoporous alumina membranes demonstrated antimicrobial activity against Escherichia coli and Staphylococcus aureus bacteria. These results suggest that atomic layer deposition is an attractive technique for modifying the surfaces of nanoporous alumina membranes and other nanostructured biomaterials.more » Nanoporous alumina, also known as anodic aluminum oxide (AAO), is a nanomaterial that exhibits several unusual properties, including high pore densities, straight pores, small pore sizes, and uniform pore sizes. In 1953, Keller et al. showed that anodizing aluminum in acid electrolytes results in a thick layer of nearly cylindrical pores, which are arranged in a close-packed hexagonal cell structure. More recently, Matsuda & Fukuda demonstrated preparation of highly ordered platinum and gold nanohole arrays using a replication process. In this study, a negative structure of nanoporous alumina was initially fabricated and a positive structure of a nanoporous metal was subsequently fabricated. Over the past fifteen years, nanoporous alumina membranes have been used as templates for growth of a variety of nanostructured materials, including nanotubes, nanowires, nanorods, and nanoporous membranes.« less

Determination of small and large amounts of fluorine in rocks

USGS Publications Warehouse

Grimaldi, F.S.; Ingram, B.; Cuttitta, F.

1955-01-01

Gelatinous silica and aluminum ions retard the distillation of fluorine in the Willard and Winter distillation method. A generally applicable, simple method for the determination of fluorine in rocks containing aluminum or silicon or both as major constituents was desired. In the procedure developed, the sample is fused with a mixture of sodium carbonate and zinc oxide, leached with water, and filtered. The residue is granular and retains nearly all of the silica. The fluorine in the filtrate is distilled directly from a perchloric acid-phosphoric acid mixture. Phosphoric acid permits the quantitative distillation of fluorine in the presence of much aluminum at the usual distillation temperature and without the collection of large volumes of distillate. The fluorine is determined either by microtitration with thorium nitrate or colorimetrically with thoron. The procedure is rapid and has yielded excellent results on silicate rocks and on samples from the aluminum phosphate (leached) zone of the Florida phosphate deposits.

Influence of various thickness metallic interlayers on opto-electric and mechanical properties of AZO thin films on PET substrates

NASA Astrophysics Data System (ADS)

Chang, R. C.; Li, T. C.; Lin, C. W.

2012-02-01

Various thickness metallic interlayers to improve the opto-electric and mechanical properties of aluminum-doped zinc oxide (AZO) thin films deposited on flexible polyethylene terephtalate (PET) substrates are studied. The effects of the interlayers on the resistance and transmittance of the AZO thin films are discussed. The result shows that the metallic interlayers effectively improve the electric resistance but reduce the optical transmittance of the AZO thin films. These phenomena become more obvious as the interlayer thickness increases. However, the AZO with an aluminum interlayer still behaves an acceptable transmittance. Moreover, mechanical tests indicate that the aluminum interlayer increases the hardness and modulus, and reduce the residual stress of the AZO thin films. In contrast, the silver and copper interlayers decrease the AZO's mechanical properties. Comparing to those without any interlayer, the results show that the best interlayer is the 6 nm thick aluminum film.

21 CFR 73.1646 - Bronze powder.

Code of Federal Regulations, 2012 CFR

2012-04-01

... electrolytic copper and zinc with small amounts of the virgin metals aluminum and tin. It contains small... part per million Aluminum (as Al), not more than 0.5 percent. Tin (as Sn), not more than 0.5 percent... percent. Maximum particle size 45µ (95 percent minimum). Aluminum, zinc, tin, and copper content shall be...

21 CFR 73.1646 - Bronze powder.

Code of Federal Regulations, 2011 CFR

2011-04-01

... electrolytic copper and zinc with small amounts of the virgin metals aluminum and tin. It contains small... part per million Aluminum (as Al), not more than 0.5 percent. Tin (as Sn), not more than 0.5 percent... percent. Maximum particle size 45µ (95 percent minimum). Aluminum, zinc, tin, and copper content shall be...

21 CFR 73.1646 - Bronze powder.

Code of Federal Regulations, 2014 CFR

2014-04-01

... electrolytic copper and zinc with small amounts of the virgin metals aluminum and tin. It contains small... part per million Aluminum (as Al), not more than 0.5 percent. Tin (as Sn), not more than 0.5 percent... percent. Maximum particle size 45µ (95 percent minimum). Aluminum, zinc, tin, and copper content shall be...

21 CFR 73.1646 - Bronze powder.

Code of Federal Regulations, 2013 CFR

2013-04-01

... electrolytic copper and zinc with small amounts of the virgin metals aluminum and tin. It contains small... part per million Aluminum (as Al), not more than 0.5 percent. Tin (as Sn), not more than 0.5 percent... percent. Maximum particle size 45µ (95 percent minimum). Aluminum, zinc, tin, and copper content shall be...

21 CFR 73.1646 - Bronze powder.

Code of Federal Regulations, 2010 CFR

2010-04-01

... electrolytic copper and zinc with small amounts of the virgin metals aluminum and tin. It contains small... part per million Aluminum (as Al), not more than 0.5 percent. Tin (as Sn), not more than 0.5 percent... percent. Maximum particle size 45µ (95 percent minimum). Aluminum, zinc, tin, and copper content shall be...

Wood surface modification by in-situ sol-gel deposition of hybrid inorganic-organic thin films

Treesearch

Mandla A. Tshabalala; Li-Piin Sung

2007-01-01

Interest in the use of nanoparticles of iron, titanium, aluminum, and zinc oxides in transparent coatings for wood is increasing. Such nano-composite coatings have the potential of not only preserving the natural color of the wood, but also stabilizing the wood surface against the combined degradative effects of sunlight and moisture. The nanoparticles can be used as...

Toxicity of Military Unique Compounds in Aquatic Organisms: An Annotated Bibliography (Studies Published Through 1996)

DTIC Science & Technology

1998-04-01

containing zinc, cadmium , arsenic, lead, aluminum, carbon tetrachloride, perchloroethylene, hexachloroethane, hexachlorobenzene, and hydrochloric...Siphonaptera/Solvent Dyes/Toxicity/Trout/Water/Zinc/SmokeMunitions/Propellants/Water Pollution/ Cadmium /Lead(Metal)/Carbon Tetrachloride/Aquatic Biology...combustion products that are a complex mixture containing zinc, cadmium , arsenic, lead, aluminum, carbon tetrachloride, perchloroethylene

Zinc alloy enhances strength and creep resistance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Machler, M.

1996-10-01

A family of high-performance ternary zinc-copper-aluminum alloys has been developed that provides higher strength, hardness, and creep resistance than the traditional zinc-aluminum alloys Zamak 3, Zamak 5, and ZA-8. Designated ACuZinc, mechanical properties comparable to those of more expensive materials make it suitable for high-load applications and those at elevated temperatures. This article describes the alloy`s composition, properties, and historical development.

Fabrication of ZnO Nanowires Arrays by Anodization and High-Vacuum Die Casting Technique, and Their Piezoelectric Properties.

PubMed

Kuo, Chin-Guo; Chang, Ho; Wang, Jian-Hao

2016-03-24

In this investigation, anodic aluminum oxide (AAO) with arrayed and regularly arranged nanopores is used as a template in the high-vacuum die casting of molten zinc metal (Zn) into the nanopores. The proposed technique yields arrayed Zn nanowires with an aspect ratio of over 600. After annealing, arrayed zinc oxide (ZnO) nanowires are obtained. Varying the anodizing time yields AAO templates with thicknesses of approximately 50 μm, 60 μm, and 70 μm that can be used in the fabrication of nanowires of three lengths with high aspect ratios. Experimental results reveal that a longer nanowire generates a greater measured piezoelectric current. The ZnO nanowires that are fabricated using an alumina template are anodized for 7 h and produce higher piezoelectric current of up to 69 pA.

PROCESS OF MAKING SHAPED FUEL FOR NUCLEAR REACTORS

DOEpatents

O'Leary, W.J.; Fisher, E.A.

1964-02-11

A process for making uranium dioxide fuel of great strength, density, and thermal conductivity by mixing it with 0.1 to 1% of a densifier oxide (tin, aluminum, zirconium, ferric, zinc, chromium, molybdenum, titanium, or niobium oxide) and with a plasticizer (0.5 to 3% of bentonite and 0.05 to 2% of methylcellulose, propylene glycol alginate, or ammonium alginate), compacting the mixture obtained, and sintering the bodies in an atmosphere of carbon monoxide or carbon dioxide, with or without hydrogen, or of a nitrogen-hydrogen mixture is described. (AEC)

Material morphology and electrical resistivity differences in EPDM rubbers.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Nancy Y. C.; Domeier, Linda A.

2008-03-01

Electrical resistance anomalies noted in EPDM gaskets have been attributed to zinc-enriched surface sublayers, about 10-{micro}m thick, in the sulfur cured rubber material. Gasket over-compression provided the necessary connector pin contact and was also found to cause surprising morphological changes on the gasket surfaces. These included distributions of zinc oxide whiskers in high pressure gasket areas and cone-shaped features rich in zinc, oxygen, and sulfur primarily in low pressure protruding gasket areas. Such whiskers and cones were only found on the pin side of the gaskets in contact with a molded plastic surface and not on the back side inmore » contact with an aluminum surface. The mechanisms by which such features are formed have not yet been defined.« less

Percentage of different aluminum doping influence the morphological and optical properties of ZnO nanostructured growth for sensor application

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mohamed, R., E-mail: ruziana12@gmail.com; NANO-SciTech Centre, Institue of Science, Universiti Teknologi MARA, 40450 Shah Alam, Selangor; Faculty of Applied Sciences, Universiti Teknologi MARA Pahang, 26400 Bandar Tun Razak Jengka, Pahang

In this work, Zinc Oxide (ZnO) with different aluminum (Al) doping percentage was synthesis by sol gel immersion method. Al doped ZnO at various doping percentage from 1, 2, 3, 4 and 5. It was found that with different Al percentage influence the morphological and optical properties of ZnO growth. Field Emission Scanning Electron Microscope (FESEM) image showed the use of different Al doping causes the difference in geometry and size of ZnO nanorods growth. Based on UV-Vis spectroscopy, the transmittance at 1% Al doping has the highest spectrum.

Modification of optical and electrical properties of zinc oxide-coated porous silicon nanostructures induced by swift heavy ion

PubMed Central

2012-01-01

Morphological and optical characteristics of radio frequency-sputtered zinc aluminum oxide over porous silicon (PS) substrates were studied before and after irradiating composite films with 130 MeV of nickel ions at different fluences varying from 1 × 1012 to 3 × 1013 ions/cm2. The effect of irradiation on the composite structure was investigated by scanning electron microscopy, X-ray diffraction (XRD), photoluminescence (PL), and cathodoluminescence spectroscopy. Current–voltage characteristics of ZnO-PS heterojunctions were also measured. As compared to the granular crystallites of zinc oxide layer, Al-doped zinc oxide (ZnO) layer showed a flaky structure. The PL spectrum of the pristine composite structure consists of the emission from the ZnO layer as well as the near-infrared emission from the PS substrate. Due to an increase in the number of deep-level defects, possibly oxygen vacancies after swift ion irradiation, PS-Al-doped ZnO nanocomposites formed with high-porosity PS are shown to demonstrate a broadening in the PL emission band, leading to the white light emission. The broadening effect is found to increase with an increase in the ion fluence and porosity. XRD study revealed the relative resistance of the film against the irradiation, i.e., the irradiation of the structure failed to completely amorphize the structure, suggesting its possible application in optoelectronics and sensing applications under harsh radiation conditions. PMID:22748164

Cadmiun and Zinc Adsorption by Acric Soils

NASA Astrophysics Data System (ADS)

da Silva, Luiz Gabriel; Colato, Alexandre; Casagrande, José Carlos; Soares, Marcio Roberto

2017-04-01

Acrodox soils are very weathered soils, characterized by having buildup of iron and aluminum oxides and hydroxides. These soils are present in extensive productive regions in the state of São Paulo. This work aimed at verifying the adequacy of constant capacitance model in describing the adsorption of cadmium and zinc in Anionic Rhodic Acrudox, Anionic Xanthic Acrudox and Rhodic Hapludalf. The chemical, mineralogical and physical attributes of these soils were determined in the layers 0-20 cm and 20-40 cm. Adsorption data of cadmium and zinc were also previously determined for samples of both layers of each soil. Were applied 5 mg dm-3 of cadmium and zinc to 2,0 g of soil to ample pH range (3 to 10) to build the adsorption envelops to three ionic strength. The constant capacitance model was adequate to simulate the adsorption of zinc and cadmium. It was not possible to make appropriate distinctions between measurements and simulations for two soil layers studied, neither between the three concentrations of background electrolyte.

40 CFR 467.12 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2010 CFR

2010-07-01

... rolled with neat oils Chromium 0.0360 0.0147 Cyanide 0.0237 0.0098 Zinc 0.119 0.0498 Aluminum 0.525 0.257... aluminum rolled with neat oils Chromium 0.0244 0.010 Cyanide 0.0161 0.0067 Zinc 0.0808 0.0338 Aluminum 0... off-lbs) of aluminum sheet cast by continuous methods Chromium 0.00086 0.00035 Cyanide 0.00057 0.00024...

Biomedical application of hierarchically built structures based on metal oxides

NASA Astrophysics Data System (ADS)

Korovin, M. S.; Fomenko, A. N.

2017-12-01

Nowadays, the use of hierarchically built structures in biology and medicine arouses much interest. The aim of this work is to review and summarize the available literature data about hierarchically organized structures in biomedical application. Nanoparticles can serve as an example of such structures. Medicine holds a special place among various application methods of similar systems. Special attention is paid to inorganic nanoparticles based on different metal oxides and hydroxides, such as iron, zinc, copper, and aluminum. Our investigations show that low-dimensional nanostructures based on aluminum oxides and hydroxides have an inhibitory effect on tumor cells and possess an antimicrobial activity. At the same time, it is obvious that the large-scale use of nanoparticles by humans needs to thoroughly study their properties. Special attention should be paid to the study of nanoparticle interaction with living biological objects. The numerous data show that there is no clear understanding of interaction mechanisms between nanoparticles and various cell types.

Influence of sputtering deposition parameters on electrical and optical properties of aluminium-doped zinc oxide thin films for photovoltaic applications

NASA Astrophysics Data System (ADS)

Krawczak, Ewelina; Agata, Zdyb; Gulkowski, Slawomir; Fave, Alain; Fourmond, Erwann

2017-11-01

Transparent Conductive Oxides (TCOs) characterized by high visible transmittance and low electrical resistivity play an important role in photovoltaic technology. Aluminum doped zinc oxide (AZO) is one of the TCOs that can find its application in thin film solar cells (CIGS or CdTe PV technology) as well as in other microelectronic applications. In this paper some optical and electrical properties of ZnO:Al thin films deposited by RF magnetron sputtering method have been investigated. AZO layers have been deposited on the soda lime glass substrates with use of variable technological parameters such as pressure in the deposition chamber, power applied and temperature during the process. The composition of AZO films has been investigated by EDS method. Thickness and refraction index of the deposited layers in dependence on certain technological parameters of sputtering process have been determined by spectroscopic ellipsometry. The measurements of transmittance and sheet resistance were also performed.

Transparent conducting thin films for spacecraft applications

NASA Technical Reports Server (NTRS)

Perez-Davis, Marla E.; Malave-Sanabria, Tania; Hambourger, Paul; Rutledge, Sharon K.; Roig, David; Degroh, Kim K.; Hung, Ching-Cheh

1994-01-01

Transparent conductive thin films are required for a variety of optoelectronic applications: automotive and aircraft windows, and solar cells for space applications. Transparent conductive coatings of indium-tin-oxide (ITO)-magnesium fluoride (MgF2) and aluminum doped zinc oxide (AZO) at several dopant levels are investigated for electrical resistivity (sheet resistance), carrier concentration, optical properties, and atomic oxygen durability. The sheet resistance values of ITO-MgF2 range from 10(exp 2) to 10(exp 11) ohms/square, with transmittance of 75 to 86 percent. The AZO films sheet resistances range from 10(exp 7) to 10(exp 11) ohms/square with transmittances from 84 to 91 percent. It was found that in general, with respect to the optical properties, the zinc oxide (ZnO), AZO, and the high MgF2 content ITO-MgF2 samples, were all durable to atomic oxygen plasma, while the low MgF2 content of ITO-MgF2 samples were not durable to atomic oxygen plasma exposure.

Transparent conducting thin films for spacecraft applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Perez-Davis, M.E.; Malave-Sanabria, T.; Hambourger, P.

1994-01-01

Transparent conductive thin films are required for a variety of optoelectronic applications: automotive and aircraft windows, and solar cells for space applications. Transparent conductive coatings of indium-tin-oxide (ITO)-magnesium fluoride (MgF2) and aluminum doped zinc oxide (AZO) at several dopant levels are investigated for electrical resistivity (sheet resistance), carrier concentration, optical properties, and atomic oxygen durability. The sheet resistance values of ITO-MgF2 range from 10[sup 2] to 10[sup 11] ohms/square, with transmittance of 75 to 86 percent. The AZO films sheet resistances range from 10[sup 7] to 10[sup 11] ohms/square with transmittances from 84 to 91 percent. It was found thatmore » in general, with respect to the optical properties, the zinc oxide (ZnO), AZO, and the high MgF2 content ITO-MgF2 samples, were all durable to atomic oxygen plasma, while the low MgF2 content of ITO-MgF2 samples were not durable to atomic oxygen plasma exposure.« less

High temperature regenerative H.sub.2 S sorbents

NASA Technical Reports Server (NTRS)

Flytani-Stephanopoulos, Maria (Inventor); Gavalas, George R. (Inventor); Tamhankar, Satish S. (Inventor)

1988-01-01

Efficient, regenerable sorbents for removal of H.sub.2 S from high temperature gas streams comprise porous, high surface area particles. A first class of sorbents comprise a thin film of binary oxides that form a eutectic at the temperature of the gas stream coated onto a porous, high surface area refractory support. The binary oxides are a mixture of a Group VB or VIB metal oxide with a Group IB, IIB or VIII metal oxide such as a film of V-Zn-O, V-Cu-O, Cu-Mo-O, Zn-Mo-O or Fe-Mo-O coated on an alumina support. A second class of sorbents consist of particles of unsupported mixed oxides in the form of highly dispersed solid solutions of solid compounds characterized by small crystallite size, high porosity and relatively high surface area. The mixed oxide sorbents contain one Group IB, IIB or VIIB metal oxide such as copper, zinc or manganese and one or more oxides of Groups IIIA, VIB or VII such as aluminum, iron or molybdenum. The presence of iron or aluminum maintains the Group IB, IIB or VIIB metal in its oxidized state. Presence of molybdenum results in eutectic formation at sulfidation temperature and improves the efficiency of the sorbent.

40 CFR 467.33 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2011 CFR

2011-07-01

.../million off-lbs) of aluminum extruded Chromium 0.15 0.061 Cyanide 0.098 0.041 Zinc 0.49 0.21 Aluminum 2.19... Chromium 0.65 0.27 Cyanide 0.43 0.18 Zinc 2.16 0.90 Aluminum 9.51 4.73 Subpart C Direct Chill Casting... Maximum for monthly average mg/off-kg (lb/million off-lbs) of aluminum cast Chromium 0.59 0.24 Cyanide 0...

The Corrosion Protection of 2219-T87 Aluminum by Organic and Inorganic Zinc-Rich Primers

NASA Technical Reports Server (NTRS)

Danford, M. D.; Mendrek, M. J.; Walsh, D. W.

1995-01-01

The behavior of zinc-rich primer-coated 2219-T87 aluminum in a 3.5-percent Na-Cl was investigated using electrochemical techniques. The alternating current (ac) method of electrochemical impedance spectroscopy (EIS), in the frequency range of 0.001 to 40,000 Hz, and the direct current (dc) method of polarization resistance (PR) were used to evaluate the characteristics of an organic, epoxy zinc-rich primer and an inorganic, ethyl silicate zinc-rich primer. A dc electrochemical galvanic corrosion test was also used to determine the corrosion current of each zinc-rich primer anode coupled to a 2219-T87 aluminum cathode. Duration of the EIS/PR and galvanic testing was 21 days and 24 h, respectively. The galvanic test results demonstrated a very high galvanic current between the aluminum cathode and both zinc-rich primer anodes (37.9 pA/CM2 and 23.7 pA/CM2 for the organic and inorganic primers, respectively). The PR results demonstrated a much higher corrosion rate of the zinc in the inorganic primer than in the organic primer, due primarily to the higher porosity in the former. Based on this investigation, the inorganic zinc-rich primer appears to provide superior galvanic protection and is recommended for additional study for application in the solid rocket booster aft skirt.

The corrosion protection of 2219-T87 aluminum by organic and inorganic zinc-rich primers

NASA Technical Reports Server (NTRS)

Danford, M. D.; Mendrek, M. J.; Walsh, D. W.

1995-01-01

The behavior of zinc-rich primer-coated 2219-T87 aluminum in a 3.5-percent Na-Cl was investigated using electrochemical techniques. The alternating current (ac) method of electro-chemical impedance spectroscopy (EIS), in the frequency range of 0.001 to 40,000 Hz, and the direct current (dc) method of polarization resistance (PR) were used to evaluate the characteristics of an organic, epoxy zinc-rich primer and an inorganic, ethyl silicate zinc-rich primer. A dc electrochemical galvanic corrosion test was also used to determine the corrosion current of each zinc-rich primer anode coupled to a 2219-T87 aluminum cathode. Duration of the EIS/PR and galvanic testing was 21 days and 24 h, respectively. the galvanic test results demonstrated a very high galvanic current between the aluminum cathode and both zinc-rich primer anodes (37.9 micro A/cm(exp 2) and 23.7 micro A/cm(exp 2) for the organic and inorganic primers, respectively). The PR results demonstrated a much higher corrosion rate of the zinc in the inorganic primer than in the organic primer, due primarily to the higher porosity in the former. Based on this investigation, the inorganic zinc-rich primer appears to provide superior galvanic protection and is recommended for additional study for application in the solid rocket booster aft skirt.

REFRACTORY DIE FOR EXTRUDING URANIUM

DOEpatents

Creutz, E.C.

1959-08-11

A die is presented for the extrusion of metals, said die being formed of a refractory complex oxide having the composition M/sub n/O/sub m/R/sub x/O/sub y/ where M is magnesium, zinc, manganese, or iron, R is aluminum, chromic chromium, ferric iron, or manganic manganese, and m, n, x, and y are whole numbers. Specific examples are spinel, magnesium aluminate, magnetite, magnesioferrite, chromite, and franklinite.

Testing piezoelectric sensors in a nuclear reactor environment

NASA Astrophysics Data System (ADS)

Reinhardt, Brian T.; Suprock, Andy; Tittmann, Bernhard

2017-02-01

Several Department of Energy Office of Nuclear Energy (DOE-NE) programs, such as the Fuel Cycle Research and Development (FCRD), Advanced Reactor Concepts (ARC), Light Water Reactor Sustainability, and Next Generation Nuclear Power Plants (NGNP), are investigating new fuels, materials, and inspection paradigms for advanced and existing reactors. A key objective of such programs is to understand the performance of these fuels and materials during irradiation. In DOE-NE's FCRD program, ultrasonic based technology was identified as a key approach that should be pursued to obtain the high-fidelity, high-accuracy data required to characterize the behavior and performance of new candidate fuels and structural materials during irradiation testing. The radiation, high temperatures, and pressure can limit the available tools and characterization methods. In this work piezoelectric transducers capable of making these measurements are developed. Specifically, three piezoelectric sensors (Bismuth Titanate, Aluminum Nitride, and Zinc Oxide) are tested in the Massachusetts Institute of Technology Research reactor to a fast neutron fluence of 8.65×1020 nf/cm2. It is demonstrated that Bismuth Titanate is capable of transduction up to 5 × 1020 nf/cm2, Zinc Oxide is capable of transduction up to at least 6.27 × 1020 nf/cm2, and Aluminum Nitride is capable of transduction up to at least 8.65 × 1020 nf/cm2.

Simulation the spatial resolution of an X-ray imager based on zinc oxide nanowires in anodic aluminium oxide membrane by using MCNP and OPTICS Codes

NASA Astrophysics Data System (ADS)

Samarin, S. N.; Saramad, S.

2018-05-01

The spatial resolution of a detector is a very important parameter for x-ray imaging. A bulk scintillation detector because of spreading of light inside the scintillator does't have a good spatial resolution. The nanowire scintillators because of their wave guiding behavior can prevent the spreading of light and can improve the spatial resolution of traditional scintillation detectors. The zinc oxide (ZnO) scintillator nanowire, with its simple construction by electrochemical deposition in regular hexagonal structure of Aluminum oxide membrane has many advantages. The three dimensional absorption of X-ray energy in ZnO scintillator is simulated by a Monte Carlo transport code (MCNP). The transport, attenuation and scattering of the generated photons are simulated by a general-purpose scintillator light response simulation code (OPTICS). The results are compared with a previous publication which used a simulation code of the passage of particles through matter (Geant4). The results verify that this scintillator nanowire structure has a spatial resolution less than one micrometer.

Electrochemical behavior of tube-fin assembly for an aluminum automotive condenser with improved corrosion resistance

NASA Astrophysics Data System (ADS)

Pech-Canul, M. A.; Guía-Tello, J. C.; Pech-Canul, M. I.; Aguilar, J. C.; Gorocica-Díaz, J. A.; Arana-Guillén, R.; Puch-Bleis, J.

An aluminum automotive condenser was designed to exhibit high corrosion resistance in the seawater acetic acid test (SWAAT) combining zinc coated microchannel tubes and fins made with AA4343/AA3003(Zn)/AA4343 brazing sheet. Electrochemical measurements in SWAAT solution were carried out under laboratory conditions using tube-fin assembly and individual fin and tube samples withdrawn from the condenser core. The aim was to gain information on the protective role of the zinc sacrificial layer and about changes in corrosion behavior as a function of immersion time. External corrosion of the tube-fin system was simulated by immersion of mini-core samples under open circuit conditions. The corrosion rate increased rapidly during the first 6 h and slowly afterwards. The short time behavior was related to the dissolution of the oxide film and fast dissolution of the outermost part of the zinc diffusion layer. With the aid of cross-sectional depth corrosion potential profiles, it was shown that as the sacrificial layer gets dissolved, the surface concentration of zinc decreases and the potential shifts to less negative values. The results of galvanic coupling of tube and fins in a mini-cell showed that the tube became the anode while the fins exhibited cathodic behavior. An evolution in the galvanic interaction was observed, due to the progressive dissolution of the sacrificial zinc layer. The difference of uncoupled potentials between tube and fins decreased from 71 mV to 32 mV after 84 h of galvanic coupling. At the end of such period there was still a part of the zinc sacrificial layer remaining which would serve for protection of the tube material for even longer periods and there were indications of slight corrosion in the fins.

Fabrication of ZnO Nanowires Arrays by Anodization and High-Vacuum Die Casting Technique, and Their Piezoelectric Properties

PubMed Central

Kuo, Chin-Guo; Chang, Ho; Wang, Jian-Hao

2016-01-01

In this investigation, anodic aluminum oxide (AAO) with arrayed and regularly arranged nanopores is used as a template in the high-vacuum die casting of molten zinc metal (Zn) into the nanopores. The proposed technique yields arrayed Zn nanowires with an aspect ratio of over 600. After annealing, arrayed zinc oxide (ZnO) nanowires are obtained. Varying the anodizing time yields AAO templates with thicknesses of approximately 50 μm, 60 μm, and 70 μm that can be used in the fabrication of nanowires of three lengths with high aspect ratios. Experimental results reveal that a longer nanowire generates a greater measured piezoelectric current. The ZnO nanowires that are fabricated using an alumina template are anodized for 7 h and produce higher piezoelectric current of up to 69 pA. PMID:27023546

A comparison of corrosion inhibition of magnesium aluminum and zinc aluminum vanadate intercalated layered double hydroxides on magnesium alloys

NASA Astrophysics Data System (ADS)

Guo, Lian; Zhang, Fen; Lu, Jun-Cai; Zeng, Rong-Chang; Li, Shuo-Qi; Song, Liang; Zeng, Jian-Min

2018-04-01

The magnesium aluminum and zinc aluminum layered double hydroxides intercalated with NO3 -(MgAl-NO3-LDH and ZnAl-NO3-LDH) were prepared by the coprecipitation method, and the magnesium aluminum and the zinc aluminum layered double hydroxides intercalated with VO x -(MgAl-VO x -LDH and ZnAl-VO x -LDH) were prepared by the anion-exchange method. Morphologies, microstructures and chemical compositions of LDHs were investigated by SEM, EDS, XRD, FTIR, Raman and TG analyses. The immersion tests were carried to determine the corrosion inhibition properties of MgAl-VO x -LDH and ZnAl-VO x -LDH on AZ31 Mg alloys. The results showed that ZnAl-VO x -LDH possesses the best anion-exchange and inhibition abilities. The influence of treatment parameters on microstructures of LDHs were discussed. Additionally, an inhibition mechanism for ZnAl-VO x -LDH on the AZ31 magnesium alloy was proposed and discussed.

Effect of Zinc Coatings on Joint Properties and Interfacial Reactions in Aluminum to Steel Ultrasonic Spot Welding

NASA Astrophysics Data System (ADS)

Haddadi, F.; Strong, D.; Prangnell, P. B.

2012-03-01

Dissimilar joining of aluminum to steel sheet in multimaterial automotive structures is an important potential application of ultrasonic spot welding (USW). Here, the weldability of different zinc-coated steels with aluminum is discussed, using a 2.5-kW USW welder. Results show that soft hot-dipped zinc (DX56-Z)-coated steel results in better weld performance than hard (galv-annealed) zinc coatings (DX53-ZF). For Al to hard galv-annealed-coated steel welds, lap shear strengths reached a maximum of ~80% of the strength of an Al-Al joint after a 1.0 s welding time. In comparison, welds between Al6111-T4 and hot dipped soft zinc-coated steel took longer to achieve the same maximum strength, but nearly matched the Al-Al joint properties. The reasons for these different behaviors are discussed in terms of the interfacial reactions between the weld members.

Development of high-efficiency solar cells on silicon web

NASA Technical Reports Server (NTRS)

Rohatgi, A.; Meier, D. L.; Campbell, R. B.; Seidensticker, R. G.; Rai-Choudhury, P.

1985-01-01

High-efficiency dendritic cells were discussed. The influence of twin planes and heat treatment on the location and effect of trace impurities was of particular interest. Proper heat treatment often increases efficiency by causing impurities to pile up at twin planes. Oxide passivation had a beneficial effect on efficiency. A very efficient antireflective (AR) coating of zinc selenide and magnesium fluoride was designed and fabricated. An aluminum back-surface reflector was also effective.

Thin-film transistors with a graphene oxide nanocomposite channel.

PubMed

Jilani, S Mahaboob; Gamot, Tanesh D; Banerji, P

2012-12-04

Graphene oxide (GO) and graphene oxide-zinc oxide nanocomposites (GO-ZnO) were used as channel materials on SiO(2)/Si to fabricate thin-film transistors (TFT) with an aluminum source and drain. Pure GO-based TFT showed poor field-effect characteristics. However, GO-ZnO-nanocomposite-based TFT showed better field-effect performance because of the anchoring of ZnO nanostructures in the GO matrix, which causes a partial reduction in GO as is found from X-ray photoelectron spectroscopic data. The field-effect mobility of charge carriers at a drain voltage of 1 V was found to be 1.94 cm(2)/(V s). The transport of charge carriers in GO-ZnO was explained by a fluctuation-induced tunneling mechanism.

All-Aluminum Thin Film Transistor Fabrication at Room Temperature.

PubMed

Yao, Rihui; Zheng, Zeke; Zeng, Yong; Liu, Xianzhe; Ning, Honglong; Hu, Shiben; Tao, Ruiqiang; Chen, Jianqiu; Cai, Wei; Xu, Miao; Wang, Lei; Lan, Linfeng; Peng, Junbiao

2017-02-23

Bottom-gate all-aluminum thin film transistors with multi conductor/insulator nanometer heterojunction were investigated in this article. Alumina (Al₂O₃) insulating layer was deposited on the surface of aluminum doping zinc oxide (AZO) conductive layer, as one AZO/Al₂O₃ heterojunction unit. The measurements of transmittance electronic microscopy (TEM) and X-ray reflectivity (XRR) revealed the smooth interfaces between ~2.2-nm-thick Al₂O₃ layers and ~2.7-nm-thick AZO layers. The devices were entirely composited by aluminiferous materials, that is, their gate and source/drain electrodes were respectively fabricated by aluminum neodymium alloy (Al:Nd) and pure Al, with Al₂O₃/AZO multilayered channel and AlO x :Nd gate dielectric layer. As a result, the all-aluminum TFT with two Al₂O₃/AZO heterojunction units exhibited a mobility of 2.47 cm²/V·s and an I on / I off ratio of 10⁶. All processes were carried out at room temperature, which created new possibilities for green displays industry by allowing for the devices fabricated on plastic-like substrates or papers, mainly using no toxic/rare materials.

Effects of size and surface of zinc oxide and aluminum-doped zinc oxide nanoparticles on cell viability inferred by proteomic analyses.

PubMed

Pan, Chih-Hong; Liu, Wen-Te; Bien, Mauo-Ying; Lin, I-Chan; Hsiao, Ta-Chih; Ma, Chih-Ming; Lai, Ching-Huang; Chen, Mei-Chieh; Chuang, Kai-Jen; Chuang, Hsiao-Chi

2014-01-01

Although the health effects of zinc oxide nanoparticles (ZnONPs) on the respiratory system have been reported, the fate, potential toxicity, and mechanisms in biological cells of these particles, as related to particle size and surface characteristics, have not been well elucidated. To determine the physicochemical properties of ZnONPs that govern cytotoxicity, we investigated the effects of size, electronic properties, zinc concentration, and pH on cell viability using human alveolar-basal epithelial A549 cells as a model. We observed that a 2-hour or longer exposure to ZnONPs induced changes in cell viability. The alteration in cell viability was associated with the zeta potentials and pH values of the ZnONPs. Proteomic profiling of A549 exposed to ZnONPs for 2 and 4 hours was used to determine the biological mechanisms of ZnONP toxicity. p53-pathway activation was the core mechanism regulating cell viability in response to particle size. Activation of the Wnt and TGFβ signaling pathways was also important in the cellular response to ZnONPs of different sizes. The cadherin and Wnt signaling pathways were important cellular mechanisms triggered by surface differences. These results suggested that the size and surface characteristics of ZnONPs might play an important role in their observed cytotoxicity. This approach facilitates the design of more comprehensive systems for the evaluation of nanoparticles.

Degradation studies of transparent conductive electrodes on electroactive poly(vinylidene fluoride) for uric acid measurements

NASA Astrophysics Data System (ADS)

Cardoso, Vanessa F.; Martins, Pedro; Botelho, Gabriela; Rebouta, Luis; Lanceros-Méndez, Senentxu; Minas, Graca

2010-08-01

Biochemical analysis of physiological fluids using, for example, lab-on-a-chip devices requires accurate mixing of two or more fluids. This mixing can be assisted by acoustic microagitation using a piezoelectric material, such as the β-phase of poly(vinylidene fluoride) (β-PVDF). If the analysis is performed using optical absorption spectroscopy and β-PVDF is located in the optical path, the material and its conductive electrodes must be transparent. Moreover, if, to improve the transmission of the ultrasonic waves to the fluids, the piezoelectric transducer is placed inside the fluidic structures, its degradation must be assessed. In this paper, we report on the degradation properties of transparent conductive oxides, namely, indium tin oxide (ITO) and aluminum-doped zinc oxide, when they are used as electrodes for providing acoustic microagitation. The latter promotes mixing of chemicals involved in the measurement of uric acid concentration in physiological fluids. The results are compared with those for aluminum electrodes. We find that β-PVDF samples with ITO electrodes do not degrade either with or without acoustic microagitation.

The precipitation of aluminum, iron and manganese at the junction of Deer Creek with the Snake River in Summit County, Colorado

USGS Publications Warehouse

Theobald, P.K.; Lakin, H.W.; Hawkins, D.B.

1963-01-01

The oxidation of disseminated pyrite in relatively acid schists and gneisses of the Snake River drainage basin provides abundant iron sulfate and sulfuric acid to ground and surface water. This acid water dissolves large quantities of many elements, particularly aluminum and surprisingly large quantities of elements, such as magnesium and zinc, not expected to be abundant in the drainage basin. The adjoining drainage to the west, Deer Creek, is underlain by basic rocks, from which the water inherits a high pH. Despite the presence of base- and precious- metal veins in the drainage basin of Deer Creek, it carries less metal than the Snake River. The principal precipitate on the bed of the Snake River is hydrated iron oxide with small quantities of the other metals. In Deer Creek manganese oxide is precipitated with iron oxide and large quantities of other metals are carried down with this precipitate. Below the junction of these streams the pH stabilizes at a near-neutral value. Iron is removed from the Snake River water at the junction, and aluminum is precipitated for some distance downstream. The aluminum precipitate carries down other metals in concentrations slightly less than that in the manganese precipitate on Deer Creek. The natural processes observed in this junction if carried to a larger scale could provide the mechanism described by Ansheles (1927) for the formation of bauxite. In the environment described, geochemical exploration by either water or stream sediment techniques is difficult because of (1) the extreme pH differential between the streams above their junction and (2) the difference in the precipitates formed on the streambeds. ?? 1963.

75 FR 55745 - Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea: Preliminary Results...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-09-14

... with corrosion-resistant metals such as zinc, aluminum, or zinc-, aluminum-, nickel- or iron-based... medium-sized company, or any large company that is not included in the five largest conglomerates based... property tax based on the location of its manufacturing facilities, Suncheon Works, in the Yulchon...

Catalyst for cracking kerosene

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hsie, C. H.

1985-06-04

A catalyst capable of cracking kerosene under lower pressure and temperature comprising kerosene; metal powder mixture of chromium powder, copper powder, lead powder, zinc powder, nickel powder, manganese powder in an amount of 12 to 13 parts by weight per 100 parts by weight of said kerosene; sulfuric acid in an amount of 15 to 30 parts by weight per 100 parts by weight of said kerosene; inorganic powder mixture of aluminum oxide powder, serpentine powder, alum powder, magnesium oxide powder, limestone powder, slake lime powder, silica powder, and granite powder in an amount of 150 to 170 parts bymore » weight per 100 parts by weight of said kerosene.« less

Selected Metals in Sediments and Streams in the Oklahoma Part of the Tri-State Mining District, 2000-2006

USGS Publications Warehouse

Andrews, William J.; Becker, Mark F.; Mashburn, Shana L.; Smith, S. Jerrod

2009-01-01

The abandoned Tri-State mining district includes 1,188 square miles in northeastern Oklahoma, southeastern Kansas, and southwestern Missouri. The most productive part of the Tri-State mining district was the 40-square mile part in Oklahoma, commonly referred to as 'the Picher mining district' in north-central Ottawa County, Oklahoma. The Oklahoma part of the Tri-State mining district was a primary producing area of lead and zinc in the United States during the first half of the 20th century. Sulfide minerals of cadmium, iron, lead, and zinc that remained in flooded underground mine workings and in mine tailings on the land surface oxidized and dissolved with time, forming a variety of oxide, hydroxide, and hydroxycarbonate metallic minerals on the land surface and in streams that drain the district. Metals in water and sediments in streams draining the mining district can potentially impair the habitat and health of many forms of aquatic and terrestrial life. Lakebed, streambed and floodplain sediments and/or stream water were sampled at 30 sites in the Oklahoma part of the Tri-State mining district by the U.S. Geological Survey and the Oklahoma Department of Environmental Quality from 2000 to 2006 in cooperation with the U.S. Environmental Protection Agency, and the Quapaw and Seneca-Cayuga Tribes of Oklahoma. Aluminum and iron concentrations of several thousand milligrams per kilogram were measured in sediments collected from the upstream end of Grand Lake O' the Cherokees. Manganese and zinc concentrations in those sediments were several hundred milligrams per kilogram. Lead and cadmium concentrations in those sediments were about 10 percent and 0.1 percent of zinc concentrations, respectively. Sediment cores collected in a transect across the floodplain of Tar Creek near Miami, Oklahoma, in 2004 had similar or greater concentrations of those metals than sediment cores collected at the upstream end of Grand Lake O' the Cherokees. The greatest concentrations of cadmium, iron, lead, and zinc were detected in sediments beneath an intermittent tributary to Tar Creek, a slough which drains mined areas near Commerce, Oklahoma. In surface water, aluminum and iron concentrations were greatest in the Neosho River, perhaps a result of runoff from areas underlain by shales. The greatest aqueous concentrations of cadmium, lead, manganese, and zinc were measured in water from Tar Creek, the primary small stream draining the Picher mining district with the largest proportion of mined area. Water from the Spring River had greater zinc concentrations than water from the Neosho River, perhaps as a result of a greater proportion of mined area in the Spring River Basin. Dissolved metals concentrations were generally much less than total metals concentrations, except for manganese and zinc at sites on Tar Creek, where seepage of ground water from the mine workings, saturated mine tailings, and/or metalliferous streambed sediments may be sources of these dissolved metals. Iron and lead concentrations generally decreased with increasing streamflow in upstream reaches of Tar Creek, indicating dilution of metals-rich ground water by runoff. Farther downstream in Tar Creek, and in the Neosho and Spring Rivers, metals concentrations tended to increase with increasing streamflow, indicating that most metals in these parts of these streams were associated with runoff and re-suspension of metals precipitated as oxide, hydroxide, and hydroxycarbonate minerals on land surface and streambeds. Estimated total aluminum, cadmium, iron, manganese, and zinc loads generally were greatest in water from the Neosho and Spring Rivers, primarily because of comparatively large streamflows in those rivers. Slight increases in metal loads in the downstream directions on those rivers indicated contributions of metals from inflows of small tributaries such as Tar Creek and from runoff.

40 CFR 466.33 - New source performance standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... GUIDELINES AND STANDARDS PORCELAIN ENAMELING POINT SOURCE CATEGORY Aluminum Basis Material Subcategory § 466....11 Nickel 5.35 0.69 3.60 0.47 Zinc 9.92 1.29 4.09 0.53 Aluminum 29.46 3.82 12.06 1.56 Iron 11.96 1.55... 0.03 0.18 0.20 Nickel 1.10 0.14 0.74 0.10 Zinc 2.03 0.27 0.84 0.11 Aluminum 6.03 0.78 2.47 0.32 Iron...

Study on performance of waterborne anticorrosive coatings on steel rebars

NASA Astrophysics Data System (ADS)

Ramaswamy, S. N.; Varalakshmi, R.; Selvaraj, R.

2017-12-01

Durability of reinforced cement concrete structures is mainly affected by corrosion of steel reinforcements. In order to protect the reinforcing bars from corrosion and to enhance the lifetime of reinforced cement concrete structural members, anticorrosive treatment to steel is of prime importance. Conventional coatings are solvent based. In this study, water based Latex was used to formulate anticorrosive coating. Latex is applied to steel specimen substrates such as plates and rods and their mechanical properties such as flexibility, abrasion, bendability, adhesive strength, impact resistance, etc. were studied. It was inferred that coating containing latex, micro silica, zinc phosphate, ferric oxide, aluminum oxide, titanium oxide and silica fume was found to possess more corrosion resistance under marine exposure conditions.

The efficacy of deferiprone on tissues aluminum removal and copper, zinc, manganese level in rabbits.

PubMed

Liu, Ping; Yao, Yu-Na; Wu, Shi-De; Dong, Huai-Jun; Feng, Guo-Chang; Yuan, Xiao-Yan

2005-08-01

The effect of 1,2-dimethyl-3-hydroxypyrid-4-one [deferiprone (DE)] on aluminum mobilization and elimination from tissues and serum as well as the influence on the excretion of trace elements, copper, zinc and manganese in rabbits was investigated. Sixteen New Zealand rabbits were randomly divided into three groups: control, Al-only and Al+DE. The Al-only and Al+DE animals received injections of Al2(SO43.18H2O 600 micromol Al/kg 5 days per week for 3 weeks. One week after the last Al injection the Al+DE rabbits were given deferiprone 750 micromol/kg/day intragastrically for 2 weeks. At the 42nd day the animals were sacrificed and the organs were taken and digested. Blood was taken from the ear artery three times (at the initiation of the experiment, before and after deferiprone administration). The aluminum and copper, zinc, manganese were determined by atomic absorption spectrophotometry. Our results showed that deferiprone could highly mobilize aluminum stores from tissues. At the end of experiment the aluminum contents of bone, kidney, liver and brain in Al+DE were significantly lower than that in Al-only rabbits. The copper, zinc, manganese contents were not affected by deferiprone administration.

Solder for oxide layer-building metals and alloys

DOEpatents

Kronberg, James W.

1992-01-01

A low temperature solder and method for soldering an oxide layer-building metal such as aluminum, titanium, tantalum or stainless steel. The comosition comprises tin and zinc; germanium as a wetting agent; preferably small amounts of copper and antimony; and a grit, such as silicon carbide. The grit abrades any oxide layer formed on the surface of the metal as the germanium penetrates beneath and loosens the oxide layer to provide good metal-to-metal contact. The germanium comprises less than aproximatley 10% by weight of the solder composition so that it provides sufficient wetting action but does not result in a melting temperature above approximately 300.degree. C. The method comprises the steps rubbing the solder against the metal surface so the grit in the solder abrades the surface while heating the surface until the solder begins to melt and the germanium penetrates the oxide layer, then brushing aside any oxide layer loosened by the solder.

Solder for oxide layer-building metals and alloys

DOEpatents

Kronberg, J.W.

1992-09-15

A low temperature solder and method for soldering an oxide layer-building metal such as aluminum, titanium, tantalum or stainless steel is disclosed. The composition comprises tin and zinc; germanium as a wetting agent; preferably small amounts of copper and antimony; and a grit, such as silicon carbide. The grit abrades any oxide layer formed on the surface of the metal as the germanium penetrates beneath and loosens the oxide layer to provide good metal-to-metal contact. The germanium comprises less than approximately 10% by weight of the solder composition so that it provides sufficient wetting action but does not result in a melting temperature above approximately 300 C. The method comprises the steps rubbing the solder against the metal surface so the grit in the solder abrades the surface while heating the surface until the solder begins to melt and the germanium penetrates the oxide layer, then brushing aside any oxide layer loosened by the solder.

77 FR 13093 - Corrosion-Resistant Carbon Steel Flat Products From the Republic of Korea: Final Results of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-05

...-resistant metals such as zinc, aluminum, or zinc-, aluminum-, nickel- or iron-based alloys, whether or not... Special Taxation Act (RSTA) Article 26 II. Programs That Provided No Benefits During the POR A. Research and Development Grants Under the Industrial Development Act (IDA) B. Research and Development Grants...

All-Aluminum Thin Film Transistor Fabrication at Room Temperature

PubMed Central

Yao, Rihui; Zheng, Zeke; Zeng, Yong; Liu, Xianzhe; Ning, Honglong; Hu, Shiben; Tao, Ruiqiang; Chen, Jianqiu; Cai, Wei; Xu, Miao; Wang, Lei; Lan, Linfeng; Peng, Junbiao

2017-01-01

Bottom-gate all-aluminum thin film transistors with multi conductor/insulator nanometer heterojunction were investigated in this article. Alumina (Al2O3) insulating layer was deposited on the surface of aluminum doping zinc oxide (AZO) conductive layer, as one AZO/Al2O3 heterojunction unit. The measurements of transmittance electronic microscopy (TEM) and X-ray reflectivity (XRR) revealed the smooth interfaces between ~2.2-nm-thick Al2O3 layers and ~2.7-nm-thick AZO layers. The devices were entirely composited by aluminiferous materials, that is, their gate and source/drain electrodes were respectively fabricated by aluminum neodymium alloy (Al:Nd) and pure Al, with Al2O3/AZO multilayered channel and AlOx:Nd gate dielectric layer. As a result, the all-aluminum TFT with two Al2O3/AZO heterojunction units exhibited a mobility of 2.47 cm2/V·s and an Ion/Ioff ratio of 106. All processes were carried out at room temperature, which created new possibilities for green displays industry by allowing for the devices fabricated on plastic-like substrates or papers, mainly using no toxic/rare materials. PMID:28772579

Mass loading of selected major and trace elements in Lake Fork Creek near Leadville, Colorado, September-October 2001

USGS Publications Warehouse

Walton-Day, Katherine; Flynn, Jennifer L.; Kimball, Briant A.; Runkel, Robert L.

2005-01-01

A mass-loading study of Lake Fork Creek of the Arkansas River between Sugarloaf Dam and the mouth was completed in September-October 2001 to help ascertain the following: (1) variation of pH and aqueous constituent concentrations (calcium, sulfate, alkalinity, aluminum, cadmium, copper, iron, manganese, lead, and zinc) and their relation to toxicity standards along the study reach; (2) location and magnitude of sources of metal loading to Lake Fork Creek; (3) amount and locations of metal attenuation; (4) the effect of streamside wetlands on metal transport from contributing mine tunnels; and (5) the effect of organic-rich inflow from the Leadville National Fish Hatchery on water quality in Lake Fork Creek. The study was done in cooperation with the Bureau of Land Management, U.S. Department of Agriculture Forest Service, and U.S. Fish and Wildlife Service. Constituent concentrations and pH showed variable patterns over the study reach. Hardness-based acute and chronic toxicity standards were exceeded for some inflows and some constituents. However, stream concentrations did not exceed standards except for zinc starting in the upper parts of the study reach and extending to just downstream from the inflow from the Leadville National Fish Hatchery. Dilution from that inflow lowered stream zinc concentrations to less than acute and chronic toxicity standards. The uppermost 800 meters of the study reach that contained inflow from the Bartlett, Dinero, and Nelson mine tunnels and the Dinero wetland was the greatest source of loading for manganese and zinc. A middle section of the study reach that extended approximately 2 kilometers upstream from the National Fish Hatchery inflow to just downstream from that inflow was the largest source of aluminum, copper, iron, and lead loading. The loading was partially from the National Fish Hatchery inflow but also from unknown sources upstream from that inflow, possibly ground water. The largest sources for calcium and sulfate load to the stream were the parts of the study reach containing inflow from the tribu-taries Halfmoon Creek (calcium) and Willow Creek (sulfate). The Arkansas River and its tributaries upstream from Lake Fork Creek were the source of most of the calcium (70 percent), sulfate (82 percent), manganese (77 percent), lead (78 percent), and zinc (95 percent) loads in the Arkansas River downstream from the Lake Fork confluence. In contrast, Lake Fork Creek was the major source of aluminum (68 percent), copper (65 percent), and iron (87 percent) loads to the Arkansas River downstream from the confluence. Attenuation was not important for calcium, sulfate, or iron. However, other metals loads were reduced up to 81 percent over the study reach (aluminum, 25 percent; copper, 20 percent; manganese, 81 percent; lead, 30 percent; zinc, 72 percent). Metal attenuation in the stream occurred primarily in three locations (1) the irrigation diversion ditch; (2) the beaver pond complex extending from upstream from the Colorado Gulch inflow to just downstream from that inflow; and (3) the stream reach that included the inflow from Willow Creek. The most likely attenuation mechanism is precipitation of metal oxides and hydroxides (primarily manganese), and sorption or coprecipitation of trace elements with the precipitating phase. A mass-balance calculation indicated that the wetland between the Dinero Tunnel and Lake Fork Creek removed iron, had little effect on zinc mass load, and was a source for, or was releasing, aluminum and manganese. In contrast, the wetland that occurred between the Siwatch Tunnel and Lake Fork Creek removed aluminum, iron, manganese, and zinc from the tunnel drainage before it entered the creek. Inflow from the National Fish Hatchery increased dissolved organic carbon concentrations in Lake Fork Creek and slightly changed the composition of the dissolved organic carbon. However, dissolved organic carbon loads increased in the stream reach downs

Alternatives To Cadmium Plated Military Connectors

DTIC Science & Technology

2011-08-30

from Feb 2011 Asets Defense conference  Amphenol Aerospace Operations report. 9/21/2011 10 Chromate finish  Hexavalent chrome was targeted by DOD...Fluorocarbon Zinc-Nickel Pure Dense Aluminum  Zinc-Nickel and Aluminum currently contain hexavalent chromate. Nickel-Fluorocarbon requires no...to lack of available drop in replacements, but this will change as alternatives become available.  Trivalent chrome and other non- chrome

Aluminum-doped zinc oxide thin films grown on various substrates using facing target sputtering system

NASA Astrophysics Data System (ADS)

Kim, Hwa-Min; Lee, Chang Hyun; Shon, Sun Young; Kim, Bong Hwan

2017-11-01

Aluminum-doped zinc oxide (AZO) films were fabricated on various substrates, such as glass, polyethylene naphthalate (PEN), and polyethylene terephthalate (PET), at room temperature using a facing target sputtering (FTS) system with hetero ZnO and Al2O3 targets, and their electrical and optical properties were investigated. The AZO film on glass exhibited compressive stress while the films on the plastic substrates showed tensile stress. These stresses negatively affected the crystalline quality of the AZO films, and it is suggested that the poor crystalline quality of the films may be related to the neutral Al-based defect complexes formed in the films; these complexes act as neutral impurity scattering centers. AZO films with good optoelectronic properties could be formed on the glass and plastic substrates by the FTS technique using the hetero targets. The AZO films deposited on the glass, PEN, and PET substrates showed very low resistivities, of 5.0 × 10-4 Ω cm, 7.0 × 10-4 Ω cm, and 7.4 × 10-4 Ω cm, respectively. Further, the figure merit of the AZO film formed on the PEN substrate in the visible range (400-700 nm) was significantly higher than that of the AZO film on PET and similar to that of the AZO film on glass. Finally, the average transmittances of the films in the visible range (400-700 nm) were 83.16% (on glass), 76.3% (on PEN), and 78.16% (on PET).

40 CFR 467.46 - Pretreatment standards for new sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... off-lbs) of aluminum forged Chromium 0.019 0.008 Cyanide 0.010 0.004 Zinc 0.051 0.021 TTO 0.035 Oil and grease (alternate monitoring parameter) 0.50 0.50 Subpart D Forging Scrubber Liquor Pollutant or... aluminum forged Chromium 0.035 0.014 Cyanide 0.019 0.008 Zinc 0.096 0.040 TTO 0.065 Oil and grease...

40 CFR 467.16 - Pretreatment standards for new sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Maximum for monthly average mg/off-kg (lb/million off-lbs) of aluminum rolled with neat oils Chromium 0... rolled with neat oils Chromium 0.021 0.009 Cyanide 0.011 0.005 Zinc 0.057 0.024 TTO 0.038 Oil and grease... aluminum cast Chromium 0.00073 0.00029 Cyanide 0.00039 0.00016 Zinc 0.0020 0.00082 TTO 0.0014 Oil and...

Preparation and testing of corrosion and spallation-resistant coatings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hurley, John P.; Cavalli, Matthew N.

2016-06-30

The goal of this project was to take a recently developed method of bonding oxide dispersion-strengthened (ODS) FeCrAl plating to nickel superalloys closer to commercial use in syngas-fired turbines. The project was designed to better understand and develop the bonding process and to determine if plating APMT®, a specific highly oxidation-resistant ODS FeCrAl alloy made by Kanthal, onto nickel-based superalloy turbine parts is a viable method for substantially improving the lifetimes and maximum use temperatures of the parts. The superalloys investigated for protection were CM247LC and Rene® 80, both alumina scale-forming alloys. The method for bonding the APMT plate tomore » the superalloys is called evaporative metal bonding, which involves placing a thin foil of zinc between the plate and the superalloy, clamping them together, and heating in an atmosphere-controlled furnace. Upon heating, the zinc melts and dissolves the oxide skins of the alloys at the bond line, allowing the two alloys to diffuse into each other. The zinc then diffuses through the alloys and evaporates from their surfaces, creating a bond between the APMT and the superalloy that is stronger than the APMT itself. Testing showed that the diffusivity of zinc in both APMT and CM247LC is quite similar at 700°C but 15 times higher in the APMT at 1214°C. Coefficients of thermal expansion were determined for each of the alloys as a function of temperature. This information was entered into a finite-element model using ANSYS, which was used to design a clamping jig for pressing the APMT to the superalloys at the bonding temperature. Scanning electron microscopy analyses of representative joints showed that no zinc remained in the alloys after bonding Unfortunately, the analyses also showed some small pieces of broken aluminum oxide scale near the bond lines, indicating that its scale was not sufficiently removed during prebonding cleaning. Samples from each of the bonded blocks were sent to Siemens for its standard oxidation, spallation, and corrosion testing, which was scheduled for completion in the spring of 2016. However, because of commercial demands, the tests were not completed by the time of this report except some initial spallation tests at 1150°C. In those tests, several of the APMT plates separated from the CM247LC, likely because of the remaining aluminum oxide scale on the surface of the CM247LC. This implies that surface preparation may need to include machining to remove the oxide scale before bonding rather than just sandblasting. In previous tensile testing at 950°C, the breaks in the tensile samples always occurred in the APMT and not at the joints. Gasifier sampling was completed to determine what types of trace contaminants may occur in cleaned and combusted syngas and that could lead to corrosion or deposition in turbines firing coal syngas. The sampling was done from a pressurized fluidized-bed gasifier and a pressurized entrained-flow gasifier. The particles captured on a filter from syngas were typically 0.2 to 0.5 μm in diameter, whereas those captured from the combusted syngas were slightly larger and more spherical. X-ray photoelectron spectroscopy done at Oak Ridge National Laboratory showed that the particles do not contain any metals and have an atomic composition almost identical to that of the polycarbonate filter. This indicates that the particles are primarily soot-based and not formed from volatilization of metals in the gasifiers.« less

Effect of Precursors on Key Opto-electrical Properties of Successive Ion Layer Adsorption and Reaction-Prepared Al:ZnO Thin Films

NASA Astrophysics Data System (ADS)

Kumar, K. Deva Arun; Valanarasu, S.; Ganesh, V.; Shkir, Mohd.; Kathalingam, A.; AlFaify, S.

2018-02-01

Aluminum-doped zinc oxide (Al:ZnO) thin films were deposited on glass substrates by successive ion layer adsorption and reaction (SILAR) method using different precursors. This inexpensive SILAR method involves dipping of substrate sequentially in zinc solution, de-ionized water and ethylene glycol in multiple cycles. Prepared films were investigated by x-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscope (AFM), optical absorption, photoluminescence (PL), Raman spectroscopy and electrical studies. XRD study confirmed incorporation of aluminum in ZnO lattice with a polycrystalline hexagonal wurtzite structure of the films. The crystallite size determined by the Scherrer equation showed an increase from 28 nm to 35 nm for samples S1 to S4, respectively. SEM study showed smooth morphology with homogeneous distribution of particles. From the AFM images, the surface roughness was found to change according to precursors. For the optical analysis, the zinc chloride precursor showed high optical transmittance of about 90% in the visible range with a band gap value 3.15 eV. The room-temperature PL spectra exhibited a stronger violet emission peak at 420 nm for all the prepared samples. The Raman spectra showed a peak around 435 cm-1 which could be assigned to non-polar optical phonons (E2-high) mode AZO films of a ZnO wurtzite structure. Hall effect measurements showed n-type conductivity with low resistivity ( ρ) and high carrier concentrations ( n) of 2.39 × 10-3 Ω-cm and 8.96 × 1020 cm-3, respectively, for the film deposited using zinc chloride as precursor. The above properties make the prepared AZO film to be regarded as a very promising electrode material for fabrication of optoelectronic devices.

Laser Overlap Welding of Zinc-coated Steel on Aluminum Alloy

NASA Astrophysics Data System (ADS)

Kashani, Hamed Tasalloti; Kah, Paul; Martikainen, Jukka

Local reinforcement of aluminum with laser welded patches of zinc-coated steel can effectively contribute to crashworthiness, durability and weight reduction of car body. However, the weld between Zn-coated steel and aluminum is commonly susceptible to defects such as spatter, cavity and crack. The vaporization of Zn is commonly known as the main source of instability in the weld pool and cavity formation, especially in a lap joint configuration. Cracks are mainly due to the brittle intermetallic compounds growing at the weld interface of aluminum and steel. This study provides a review on the main metallurgical and mechanical concerns regarding laser overlap welding of Zn-coated steel on Al-alloy and the methods used by researchers to avoid the weld defects related to the vaporization of Zn and the poor metallurgical compatibility between steel and aluminum.

Advanced Zinc Phosphate Conversion and Pre-Ceramic Polymetallosiloxane Coatings for Corrosion Protection of Steel and Aluminum, and Characteristics of Polyphenyletheretherketone-Based Materials

DTIC Science & Technology

1992-09-24

which the trivalent ion is the principal oxidation state, preferentially reacts with hydroxylated organosilane to form the Al-O-Si linkage at a low... tig front the carboxylic acid, COOH, in the p(AA) [6j. The spectra for all of the cobalt- and nickel-incorporated Zn-Ph samples show a slight...to study bonding in chromium , manganese, iron, and cobalt compounds J Chem Phys 57 (1972) pp 973-982 1 1 Lindberg, B.J. et at. Molecular

Investigating the Mechanisms and Potential of Silk Fiber Metallization

DTIC Science & Technology

2013-09-30

in an ALD process, when using the modified metal infiltration process as outlined by Lee et al., the titanium isopropoxide (TIP) precursor...these fibers exhibited >2-fold increase in strain to breakage, and >4.5-fold increase in strength when infiltrated with zinc, titanium , or aluminum...fibers exhibited >2-fold increase in strain to breakage, and >4.5-fold increase in strength when infiltrated with zinc, titanium , or aluminum

Transparent Conducting Oxides—An Up-To-Date Overview

PubMed Central

Stadler, Andreas

2012-01-01

Transparent conducting oxides (TCOs) are electrical conductive materials with comparably low absorption of electromagnetic waves within the visible region of the spectrum. They are usually prepared with thin film technologies and used in opto-electrical apparatus such as solar cells, displays, opto-electrical interfaces and circuitries. Here, based on a modern database-system, aspects of up-to-date material selections and applications for transparent conducting oxides are sketched, and references for detailed information are given. As n-type TCOs are of special importance for thin film solar cell production, indium-tin oxide (ITO) and the reasonably priced aluminum-doped zinc oxide (ZnO:Al), are discussed with view on preparation, characterization and special occurrences. For completion, the recently frequently mentioned typical p-type delafossite TCOs are described as well, providing a variety of references, as a detailed discussion is not reasonable within an overview publication. PMID:28817002

Bacterial toxicity comparison between nano- and micro-scaled oxide particles.

PubMed

Jiang, Wei; Mashayekhi, Hamid; Xing, Baoshan

2009-05-01

Toxicity of nano-scaled aluminum, silicon, titanium and zinc oxides to bacteria (Bacillus subtilis, Escherichia coli and Pseudomonas fluorescens) was examined and compared to that of their respective bulk (micro-scaled) counterparts. All nanoparticles but titanium oxide showed higher toxicity (at 20 mg/L) than their bulk counterparts. Toxicity of released metal ions was differentiated from that of the oxide particles. ZnO was the most toxic among the three nanoparticles, causing 100% mortality to the three tested bacteria. Al(2)O(3) nanoparticles had a mortality rate of 57% to B. subtilis, 36% to E. coli, and 70% to P. fluorescens. SiO(2) nanoparticles killed 40% of B. subtilis, 58% of E. coli, and 70% of P. fluorescens. TEM images showed attachment of nanoparticles to the bacteria, suggesting that the toxicity was affected by bacterial attachment. Bacterial responses to nanoparticles were different from their bulk counterparts; hence nanoparticle toxicity mechanisms need to be studied thoroughly.

Three dimensional-stacked complementary thin-film transistors using n-type Al:ZnO and p-type NiO thin-film transistors.

PubMed

Lee, Ching-Ting; Chen, Chia-Chi; Lee, Hsin-Ying

2018-03-05

The three dimensional inverters were fabricated using novel complementary structure of stacked bottom n-type aluminum-doped zinc oxide (Al:ZnO) thin-film transistor and top p-type nickel oxide (NiO) thin-film transistor. When the inverter operated at the direct voltage (V DD ) of 10 V and the input voltage from 0 V to 10 V, the obtained high performances included the output swing of 9.9 V, the high noise margin of 2.7 V, and the low noise margin of 2.2 V. Furthermore, the high performances of unskenwed inverter were demonstrated by using the novel complementary structure of the stacked n-type Al:ZnO thin-film transistor and p-type nickel oxide (NiO) thin-film transistor.

Energy and Process Optimization and Benchmarking of Army Industrial Processes

DTIC Science & Technology

2006-09-01

casting is a metal part formed by pouring molten iron, steel, aluminum, zinc , titanium, magnesium, copper, brass, bronze or cobalt, in nearly all...blanketing techniques. The loss of high-priced alloys is also mini- mized, while slag or dross rates are cut in half to help decrease disposal costs...fabricated of iron and steel; hot dip coating such items with aluminum, lead, or zinc ; retin- ning cans and utensils; (3) engraving, chasing and

Demonstration of Al:ZnO as a plasmonic component for near-infrared metamaterials

PubMed Central

Naik, Gururaj V.; Liu, Jingjing; Kildishev, Alexander V.; Shalaev, Vladimir M.; Boltasseva, Alexandra

2012-01-01

Noble metals such as gold and silver are conventionally used as the primary plasmonic building blocks of optical metamaterials. Making subwavelength-scale structural elements from these metals not only seriously limits the optical performance of a device due to high absorption, it also substantially complicates the manufacturing process of nearly all metamaterial devices in the optical wavelength range. As an alternative to noble metals, we propose to use heavily doped oxide semiconductors that offer both functional and fabrication advantages in the near-infrared wavelength range. In this letter, we replace a metal with aluminum-doped zinc oxide as a new plasmonic material and experimentally demonstrate negative refraction in an Al:ZnO/ZnO metamaterial in the near-infrared range. PMID:22611188

Characteristics of joining and hybrid composite forging of aluminum solid parts and galvanized steel sheets

NASA Astrophysics Data System (ADS)

Wesling, V.; Treutler, K.; Bick, T.; Stonis, M.; Langner, J.; Kriwall, M.

2018-06-01

In lightweight construction, light metals like aluminum are used in addition to high-strength steels. However, a welded joint of aluminum and steel leads to the precipitation of brittle, intermetallic phases and contact corrosion. Nevertheless, to use the advantages of this combination in terms of weight saving composite hybrid forging has been developed. In this process, an aluminum solid part and a steel sheet were formed in a single step and joined at the same time with zinc as brazing material. For this purpose, the zinc was applied by hot dipping on the aluminum in order to produce a connection via this layer in a forming process, under pressure and heat. Due to the formed intermediate layer of zinc, the formation of the Fe-Al intermetallic phases and the contact corrosion are excluded. By determining the mathematical relationships between joining parameters and the connection properties the strength of a specific joint geometry could be adjusted to reach the level of conventional joining techniques. In addition to the presentation of the joint properties, the influence of the joining process on the structure of the involved materials is also shown. Furthermore, the failure behavior under static tensile and shear stress will be shown.

NAVAIR Progress in Assessing, Validating and Implementing Non-Chromate Primers (Briefing charts)

DTIC Science & Technology

2011-02-09

logistics for any new coating or coating system NAVAIR Application Areas for Hexavalent Chromium Alternatives: Status Components/ Structure... Hexavalent chromium alternatives Sacrificial Coating Post Treatment MIL-A-8625 Anodize Avionics/ Electronics Magnesium/Titanium Conversion Aluminum Anodizing...Aluminum Pretreatment Type IC Seal Type IIB Seal Type II Seal Phosphating Rinse (Aluminum)Rinse (Steel) Cadmium Zinc-Nickel Aluminum Bonding Chrome

Dust Explosion Characteristics of Aluminum, Titanium, Zinc, and Iron-Based Alloy Powders Used in Cold Spray Processing

NASA Astrophysics Data System (ADS)

Sakata, K.; Tagomori, K.; Sugiyama, N.; Sasaki, S.; Shinya, Y.; Nanbu, T.; Kawashita, Y.; Narita, I.; Kuwatori, K.; Ikeda, T.; Hara, R.; Miyahara, H.

2014-01-01

Compared to conventional thermal spray coating, cold spray processing typically employs finer, smaller-diameter metal powders. Furthermore, cold-sprayed particles exhibit fewer surface oxides than thermally sprayed particles due to the absence of particle melting during spraying. For these reasons, it is important to consider the potential for dust explosions or fires during cold spray processing, for both industrial and R&D applications. This work examined the dust explosion characteristics of metal powders typically used in cold spray coating, for the purpose of preventing dust explosions and fires and thus protecting the health and safety of workers and guarding against property damage. In order to safely make use of the new cold spray technology in industrial settings, it is necessary to manage the risks based on an appropriate assessment of the hazards. However, there have been few research reports focused on such risk management. Therefore, in this study, the dust explosion characteristics of aluminum, titanium, zinc, carbonyl iron, and eutectoid steel containing chromium at 4 wt.% (4 wt.% Cr-eutectoid steel) powders were evaluated according to the standard protocols JIS Z 8818, IEC61241-2-3(1994-09) section 3, and JIS Z 8817. This paper reports our results concerning the dust explosion properties of the above-mentioned metal powders.

Model for determination of mid-gap states in amorphous metal oxides from thin film transistors

NASA Astrophysics Data System (ADS)

Bubel, S.; Chabinyc, M. L.

2013-06-01

The electronic density of states in metal oxide semiconductors like amorphous zinc oxide (a-ZnO) and its ternary and quaternary oxide alloys with indium, gallium, tin, or aluminum are different from amorphous silicon, or disordered materials such as pentacene, or P3HT. Many ZnO based semiconductors exhibit a steep decaying density of acceptor tail states (trap DOS) and a Fermi level (EF) close to the conduction band energy (EC). Considering thin film transistor (TFT) operation in accumulation mode, the quasi Fermi level for electrons (Eq) moves even closer to EC. Classic analytic TFT simulations use the simplification EC-EF> `several'kT and cannot reproduce exponential tail states with a characteristic energy smaller than 1/2 kT. We demonstrate an analytic model for tail and deep acceptor states, valid for all amorphous metal oxides and include the effect of trap assisted hopping instead of simpler percolation or mobility edge models, to account for the observed field dependent mobility.

Aluminum concentration and substrate temperature in chemical sprayed ZnO:Al thin solid films

NASA Astrophysics Data System (ADS)

Lozada, Erick Velázquez; Castañeda, L.; Aguilar, E. Austria

2018-02-01

The continuous interest in the synthesis and properties study of materials has permitted the development of semiconductor oxides. Zinc oxide (ZnO) with hexagonal wurzite structure is a wide band gap n-type semiconductor and interesting material over a wide range. Chemically sprayed aluminium-doped zinc oxide thin films (ZnO:Al) were deposited on soda-lime glass substrates starting from zinc pentanedionate and aluminium pentanedionate. The influence of both the dopant concentration in the starting solution and the substrate temperature on the composition, morphology, and transport properties of the ZnO:Al thin films were studied. The structure of all the ZnO:Al thin films was polycrystalline, and variation in the preferential growth with the aluminium content in the solution was observed: from an initial (002) growth in films with low Al content, switching to a predominance of (101) planes for heavily dopant regime. The crystallite size was found to decrease with doping concentration and range from 33 to 20 nm. First-order Raman scattering from ZnO:Al, all having the wurtzite structure. The assignments of the E2 mode in ZnO:Al differ from previous investigations. The film composition and the dopant concentration were determined by Auger Electron Spectroscopy (AES); these results showed that the films are almost stoichiometric ZnO. The optimum deposition conditions leading to conductive and transparent ZnO:Al thin films were also found. In this way a resistivity of 0.03 Ω-cm with a (002) preferential growth, were obtained in optimized ZnO:Al thin films.

Zinc Oxide/TiO2 Bilayer Heterojunction as a Working Electrode in Quasi Solid Dye Sensitized Solar Cells

NASA Astrophysics Data System (ADS)

Aprilia, A.; Safriani, L.; Arsyad, Wa Ode S.; Syakir, N.; Susilawati, T.; Mulyana, C.; Fitrilawati; Hidayat, R.

2017-07-01

Bilayer heterojunction of aluminium doped zinc oxide (AZO) and titanium dioxide (TiO2) mesoporous has been successfully deposited on fluorine tin oxide (FTO) substrate as working electrode in dye sensitized solar cell. This layer was used as working electrode in quasi solid dye sensitized solar cell. The solar cell structure is FTO/ZnO/TiO2/PGE/Pt/FTO using polymer gel electrolyte (PGE). In polymer gel electrolyte system, hybrid copolymer based on poly-TMSPMA (3-methoxysilyl propyl methacrylate) was used as a matrix to trap ionic liquid. An addition of aluminum as atom dopant also studied to observe the physical properties changes of photoanode related to solar cell performance. AlCl3 was used as dopant material with the concentrations at 0.5 weight % and 1.0 weight% of zinc acetate dehydrate as raw material. Based on our previous result, the existence of Al dopant would decrease the surface roughness of ZnO layer, reduce the grain size of ZnO particles, transmittance at visible light increase and also change the charge carrier density. Nevertheless, the highest efficiency was achieved for undoped ZnO/TiO2 photoanode (η=0.67%). Based on current-voltage measurement data analysis (using diode model equation) the ideality factor (n) of device using undoped ZnO was smaller (n=2.96) than AZO 0.5 wt% and 1.0 wt% (n=∼4), indicate better quality of undoped ZnO/TiO2 interfaces rather than AZO/TiO2.

Protective conversion coating on mixed-metal substrates and methods thereof

DOEpatents

O'Keefe, Matthew J.; Maddela, Surender

2016-09-06

Mixed-metal automotive vehicle bodies-in-white comprising ferrous metal surfaces, zinc surfaces, aluminum alloy surfaces, and magnesium alloy surfaces are cleaned and immersed in an aqueous bath comprising an adhesion promoter and an aqueous electrocoat bath (the adhesion promoter may be in the electrocoat bath. The adhesion promoter, which may be a cerium salt, is selected to react with each metal in the body surfaces to form an oxide layer that provides corrosion resistance for the surface and adherence for the deposited polymeric paint coating. The body is cathodic in the electrocoat deposition.

Localized surface plasmon polariton resonance in holographically structured Al-doped ZnO

DOE Office of Scientific and Technical Information (OSTI.GOV)

George, David; Lowell, David; Mao, Michelle

2016-07-28

In this paper, we studied the localized surface plasmon polariton (SPP) resonance in hole arrays in transparent conducting aluminum-doped zinc oxide (AZO). CMOS-compatible fabrication process was demonstrated for the AZO devices. The localized SPP resonance was observed and confirmed by electromagnetic simulations. Using a standing wave model, the observed SPP was dominated by the standing-wave resonance along (1,1) direction in square lattices. This research lays the groundwork for a fabrication technique that can contribute to the core technology of future integrated photonics through its extension into tunable conductive materials.

21 CFR 582.80 - Trace minerals added to animal feeds.

Code of Federal Regulations, 2011 CFR

2011-04-01

.... Manganese phosphate (dibasic). Manganese sulfate. Manganous oxide. Zinc Zinc acetate. Zinc carbonate. Zinc chloride. Zinc oxide. Zinc sulfate. ... Cobalt Cobalt acetate. Cobalt carbonate. Cobalt chloride. Cobalt oxide. Cobalt sulfate. Copper Copper...

21 CFR 582.80 - Trace minerals added to animal feeds.

Code of Federal Regulations, 2010 CFR

2010-04-01

.... Manganese phosphate (dibasic). Manganese sulfate. Manganous oxide. Zinc Zinc acetate. Zinc carbonate. Zinc chloride. Zinc oxide. Zinc sulfate. ... Cobalt Cobalt acetate. Cobalt carbonate. Cobalt chloride. Cobalt oxide. Cobalt sulfate. Copper Copper...

Metastable Phases of Dross Particles Formed in a Molten Zinc Bath and Prediction of Soluble Aluminum During Galvannealing Processes

NASA Astrophysics Data System (ADS)

Paik, Doo-Jin; Hong, Moon-Hi; Huh, Yoon; Park, Joo Hyun; Chae, Hong-Kook; Park, Seok-Ho; Choun, Si-Youl

2012-06-01

The morphology, chemistry, and crystallographic characteristics of metastable dross particles were identified. These particles are formed during the initial stage of precipitation. The particles had aluminum concentrations of 15 to 80 mass pct, with values that decreased gradually as particle size increased. These metastable dross particles were a mixture of the crystalline phase of FeZn10, which is called the "delta phase," and the high-aluminum amorphous phase, which covered the surface of the crystalline phase. The new "meta Q" concept was proposed to predict the amount of soluble aluminum in the zinc bath by considering nucleation kinetics and particle growth. The results calculated using the "meta Q" concept were compared with the values measured by the aluminum sensor, which were taken during the same period at the commercial galvanizing line. The mean of the absolute values of the differences between the calculated and measured values was 9.7 ppm.

Oceanic corrosion test of bare and zinc-protected aluminum alloys for seawater heat exchangers

NASA Technical Reports Server (NTRS)

Sasscer, D. S.; Morgan, T. O.; Rivera, C.; Ernst, R.; Scott, A. C.; Summerson, T. J.

1982-01-01

Bare 3004 tubes, 7072 Alclad 3004 tubes, and bare and zinc diffusion treated 3003 extrusions from a brazed aluminum, plate-fin heat exchanger were exposed to 1.8 m/sec flowing seawater aboard an open ocean test facility moored 3.4 km off the southeast coast of Puerto Rico. After six months exposure, the average corrosion rates for most varieties of aluminum materials converged to a low value of 0.015 mm/yr (0.6 mils/yr). Pitting did not occur in bare 3003 and 3004 samples during the six month test. Pitting did occur to varying degrees in the Alclad and zinc diffusion treated material, but did not penetrate to the base metal. Biofouling countermeasures (intermittent chlorination and brushing) did not affect the corrosion rates to any significant extent. Intermittent chlorination at a level of 0.5 ppm for 28 minutes daily controlled microbiofouling of the samples but did not prevent the development of a macrobiofouling community in areas of the plumbing with low flow.

Technology for High Pure Aluminum Oxide Production from Aluminum Scrap

NASA Astrophysics Data System (ADS)

Ambaryan, G. N.; Vlaskin, M. S.; Shkolnikov, E. I.; Zhuk, A. Z.

2017-10-01

In this study a simple ecologically benign technology of high purity alumina production is presented. The synthesis process consists of three steps) oxidation of aluminum in water at temperature of 90 °C) calcinations of Al hydroxide in atmosphere at 1100 °C) high temperature vacuum processing of aluminum alpha oxide at 1750 °C. Oxidation of aluminum scrap was carried out under intensive mixing in water with small addition of KOH as a catalyst. It was shown that under implemented experimental conditions alkali was continuously regenerated during oxidation reaction and synergistic effect of low content alkali aqueous solution and intensive mixing worked. The product of oxidation of aluminum scrap is the powder of Al(OH)3. Then it can be preliminary granulated or directly subjected to thermal treatment deleting the impurities from the product (aluminum oxide). It was shown the possibility to produce the high-purity aluminum oxide of 5N grade (99.999 %). Aluminum oxide, synthesized by means of the proposed method, meets the requirements of industrial manufacturers of synthetic sapphire (aluminum oxide monocrystals). Obtained high pure aluminum oxide can be also used for the manufacture of implants, artificial joints, microscalpels, high-purity ceramics and other refractory shapes for manufacture of ultra-pure products.

Selective Sensitization of Zinc Finger Protein Oxidation by Reactive Oxygen Species through Arsenic Binding*

PubMed Central

Zhou, Xixi; Cooper, Karen L.; Sun, Xi; Liu, Ke J.; Hudson, Laurie G.

2015-01-01

Cysteine oxidation induced by reactive oxygen species (ROS) on redox-sensitive targets such as zinc finger proteins plays a critical role in redox signaling and subsequent biological outcomes. We found that arsenic exposure led to oxidation of certain zinc finger proteins based on arsenic interaction with zinc finger motifs. Analysis of zinc finger proteins isolated from arsenic-exposed cells and zinc finger peptides by mass spectrometry demonstrated preferential oxidation of C3H1 and C4 zinc finger configurations. C2H2 zinc finger proteins that do not bind arsenic were not oxidized by arsenic-generated ROS in the cellular environment. The findings suggest that selectivity in arsenic binding to zinc fingers with three or more cysteines defines the target proteins for oxidation by ROS. This represents a novel mechanism of selective protein oxidation and demonstrates how an environmental factor may sensitize certain target proteins for oxidation, thus altering the oxidation profile and redox regulation. PMID:26063799

Substrate Selection for Fundamental Studies of Electrocatalysts and Photoelectrodes: Inert Potential Windows in Acidic, Neutral, and Basic Electrolyte

PubMed Central

Gorlin, Yelena; Jaramillo, Thomas F.

2014-01-01

The selection of an appropriate substrate is an important initial step for many studies of electrochemically active materials. In order to help researchers with the substrate selection process, we employ a consistent experimental methodology to evaluate the electrochemical reactivity and stability of seven potential substrate materials for electrocatalyst and photoelectrode evaluation. Using cyclic voltammetry with a progressively increased scan range, we characterize three transparent conducting oxides (indium tin oxide, fluorine-doped tin oxide, and aluminum-doped zinc oxide) and four opaque conductors (gold, stainless steel 304, glassy carbon, and highly oriented pyrolytic graphite) in three different electrolytes (sulfuric acid, sodium acetate, and sodium hydroxide). We determine the inert potential window for each substrate/electrolyte combination and make recommendations about which materials may be most suitable for application under different experimental conditions. Furthermore, the testing methodology provides a framework for other researchers to evaluate and report the baseline activity of other substrates of interest to the broader community. PMID:25357131

Substrate Selection for Fundamental Studies of Electrocatalysts and Photoelectrodes: Inert Potential Windows in Acidic, Neutral, and Basic Electrolyte

DOE PAGES

Benck, Jesse D.; Pinaud, Blaise A.; Gorlin, Yelena; ...

2014-10-30

The selection of an appropriate substrate is an important initial step for many studies of electrochemically active materials. In order to help researchers with the substrate selection process, we employ a consistent experimental methodology to evaluate the electrochemical reactivity and stability of seven potential substrate materials for electrocatalyst and photoelectrode evaluation. Using cyclic voltammetry with a progressively increased scan range, we characterize three transparent conducting oxides (indium tin oxide, fluorine-doped tin oxide, and aluminum-doped zinc oxide) and four opaque conductors (gold, stainless steel 304, glassy carbon, and highly oriented pyrolytic graphite) in three different electrolytes (sulfuric acid, sodium acetate, andmore » sodium hydroxide). Here, we determine the inert potential window for each substrate/electrolyte combination and make recommendations about which materials may be most suitable for application under different experimental conditions. Furthermore, the testing methodology provides a framework for other researchers to evaluate and report the baseline activity of other substrates of interest to the broader community.« less

Organosilane self-assembled layers (SAMs) and hybrid silicate magnesium-rich primers for the corrosion protection of aluminum alloy 2024 T3

NASA Astrophysics Data System (ADS)

Wang, Duhua

Although current chromate coatings function very well in corrosion protection for aircraft alloys, such as aluminum alloy 2024 T3, the U.S. Environmental Protection Agency is planning to totally ban the use of chromates as coating materials in the next decade or so because of their extremely toxic effect. For this purpose, both self-assembled layers and silicate magnesium-rich primers were tested to provide the corrosion protection for aluminum alloy. The long-term goal of this research is to develop a coating system to replace the current chromate coating for aircraft corrosion protection. Aluminum alloy 2024 T3 substrates were modified with self-assembled monolayer or multilayer thin films from different alkylsilane compounds. Mono-functional silanes, such as octadecyltrichlorosilane (C18SiCl3), can form a mixed hydrophobic monolayer or multilayer thin film on the aluminum oxide surface to provide a barrier to water and other electrolytes, so the corrosion resistance of the SAMs modified surface was increased significantly. On the other hand, the bi-functional silane self-assembly could attach the aluminum surface through the silicon headgroup while using its functional tailgroup to chemically bond the polymer coating, thus improving the adhesion between the aluminum substrate and coating substantially, and seems to contribute more to corrosion protection of aluminum substrate. Organosilanes were also combined with tetraethyl orthosilicate (TEOS) in propel ratios to form a sol-gel binder to make silicate magnesium-rich primers. Analogue to the inorganic zinc-rich coatings, the silicate magnesium-rich primers also showed excellent adhesion and solvent resistance. The sacrificial magnesium pigments and the chemically inert silicate binder both contribute to the anti-corrosion properties. Future studies will be focused on the formula optimization for better toughness, chemical resistance and anticorrosion performance.

Improved electrical performance and bias stability of solution-processed active bilayer structure of indium zinc oxide based TFT.

PubMed

Seo, Jin-Suk; Bae, Byeong-Soo

2014-09-10

We fabricated active single- and bilayer structure thin film transistors (TFTs) with aluminum or gallium doped (IZO:Al or IZO:Ga) and undoped indium zinc oxide (IZO) thin film layers using an aqueous solution process. The electrical performance and bias stability of these active single- and bilayer structure TFTs were investigated and compared to reveal the effects of Al/Gal doping and bilayer structure. The single-layer structure IZO TFT shows a high mobility of 19 cm(2)/V · s with a poor positive bias stability (PBS) of ΔVT + 3.4 V. However, Al/Ga doped in IZO TFT reduced mobility to 8.5-9.9 cm(2)/V · s but improved PBS to ΔVT + 1.6-1.7 V due to the reduction of oxygen vacancy. Thus, it is found the bilayer structure TFTs with a combination of bottom- and top-layer compositions modify both the mobility and bias stability of the TFTs to be optimized. The bilayer structure TFT with an IZO:X bottom layer possess high mobility and an IZO bottom layer improves the PBS.

Plasmonic Three-Dimensional Transparent Conductor Based on Al-Doped Zinc Oxide-Coated Nanostructured Glass Using Atomic Layer Deposition

DOE PAGES

Malek, Gary A.; Aytug, Tolga; Liu, Qingfeng; ...

2015-04-02

Transparent nanostructured glass coatings, fabricated on glass substrates, with a unique three-dimensional (3D) architecture were utilized as the foundation for the design of plasmonic 3D transparent conductors. Transformation of the non-conducting 3D structure to a conducting 3D network was accomplished through atomic layer deposition of aluminum-doped zinc oxide (AZO). After AZO growth, gold nanoparticles (AuNPs) were deposited by electronbeam evaporation to enhance light trapping and decrease the overall sheet resistance. Field emission scanning electron microscopy and atomic force microcopy images revealed the highly porous, nanostructured morphology of the AZO coated glass surface along with the in-plane dimensions of the depositedmore » AuNPs. Sheet resistance measurements conducted on the coated samples verified that the electrical properties of the 3D network are comparable to that of the untextured two-dimensional AZO coated glass substrates. In addition, transmittance measurements of the glass samples coated with various AZO thicknesses showed preservation of the highly transparent nature of each sample, while the AuNPs demonstrated enhanced light scattering as well as light-trapping capability.« less

Plasmonic Three-Dimensional Transparent Conductor Based on Al-Doped Zinc Oxide-Coated Nanostructured Glass Using Atomic Layer Deposition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Malek, Gary A.; Aytug, Tolga; Liu, Qingfeng

Transparent nanostructured glass coatings, fabricated on glass substrates, with a unique three-dimensional (3D) architecture were utilized as the foundation for the design of plasmonic 3D transparent conductors. Transformation of the non-conducting 3D structure to a conducting 3D network was accomplished through atomic layer deposition of aluminum-doped zinc oxide (AZO). After AZO growth, gold nanoparticles (AuNPs) were deposited by electronbeam evaporation to enhance light trapping and decrease the overall sheet resistance. Field emission scanning electron microscopy and atomic force microcopy images revealed the highly porous, nanostructured morphology of the AZO coated glass surface along with the in-plane dimensions of the depositedmore » AuNPs. Sheet resistance measurements conducted on the coated samples verified that the electrical properties of the 3D network are comparable to that of the untextured two-dimensional AZO coated glass substrates. In addition, transmittance measurements of the glass samples coated with various AZO thicknesses showed preservation of the highly transparent nature of each sample, while the AuNPs demonstrated enhanced light scattering as well as light-trapping capability.« less

Evaluation and control of environmental corrosion for aluminum and steel alloys

NASA Technical Reports Server (NTRS)

Franklin, D. B.

1977-01-01

Corrosion protection systems for aerospace application and the effects of surface treatments and methods of controlling stress corrosion are evaluated. Chromate pigmented systems were found to be most effective for aluminum alloys; zinc-rich coatings gave the greatest protection to steel alloys. Various steel and aluminum alloys are rated for stress corrosion resistance.

Results of a preimpoundment water-quality study of Swatara Creek, Pennsylvania

USGS Publications Warehouse

Fishel, David K.; Richardson, J.E.

1986-01-01

The impoundment will act as a sediment trap and thus reduce the concentrations of total phosphorus, iron, aluminum, lead, copper, and zinc immediately downstream from the impoundment. Large storm discharges and releases from the hypolimnion of the reservoir to attain the winter-pool level may contain low oxygen concentrations and elevated concentrations of iron, aluminum, lead, copper, and zinc. Unless conservation releases from the multi-level release gates are carefully controlled, low dissolved-oxygen levels and high metal concentrations may degrade the downstream water quality and be detrimental to the aquatic community.

Fabrication of visible light-triggered photocatalytic materials from the coupling of n-type zinc oxide and p-type copper oxide

NASA Astrophysics Data System (ADS)

Gorospe, A. B.; Herrera, M. U.

2017-04-01

Coupling of copper oxide (CuO) and zinc oxide (ZnO) was done by chemical precipitation method. In this method, copper sulfate pentahydrate and zinc sulfate heptahydrate salt precursors were separately dissolved in distilled water; then were mixed together. The copper sulfate-zinc sulfate solution was then combined with a sodium hydroxide solution. The precipitates were collected and washed in distilled water and ethanol several times, then filtered and dried. The dried sample was grounded, and then undergone heat treatment. After heating, the sample was grounded again. Zinc oxide powder and copper oxide powder were also fabricated using chemical precipitation method. X-Ray Diffraction measurements of the coupled CuO/ZnO powder showed the presence of CuO and ZnO in the fabricated sample. Furthermore, other peaks shown by XRD were also identified corresponding to copper, copper (II) oxide, copper sulfate and zinc sulfate. Results of the photocatalytic activity investigation show that the sample exhibited superior photocatalytic degradation of methyl orange under visible light illumination compared to copper oxide powder and zinc oxide powder. This may be attributed to the lower energy gap at the copper oxide-zinc oxide interface, compared to zinc oxide, allowing visible light to trigger its photocatalytic activity.

Zinc-Dependent Protection of Tobacco and Rice Cells From Aluminum-Induced Superoxide-Mediated Cytotoxicity

PubMed Central

Lin, Cun; Hara, Ayaka; Comparini, Diego; Bouteau, François; Kawano, Tomonori

2015-01-01

Al3+ toxicity in growing plants is considered as one of the major factors limiting the production of crops on acidic soils worldwide. In the last 15 years, it has been proposed that Al3+ toxicity are mediated with distortion of the cellular signaling mechanisms such as calcium signaling pathways, and production of cytotoxic reactive oxygen species (ROS) causing oxidative damages. On the other hand, zinc is normally present in plants at high concentrations and its deficiency is one of the most widespread micronutrient deficiencies in plants. Earlier studies suggested that lack of zinc often results in ROS-mediated oxidative damage to plant cells. Previously, inhibitory action of Zn2+ against lanthanide-induced superoxide generation in tobacco cells have been reported, suggesting that Zn2+ interferes with the cation-induced ROS production via stimulation of NADPH oxidase. In the present study, the effect of Zn2+ on Al3+-induced superoxide generation in the cell suspension cultures of tobacco (Nicotiana tabacum L., cell-line, BY-2) and rice (Oryza sativa L., cv. Nipponbare), was examined. The Zn2+-dependent inhibition of the Al3+-induced oxidative burst was observed in both model cells selected from the monocots and dicots (rice and tobacco), suggesting that this phenomenon (Al3+/Zn2+ interaction) can be preserved in higher plants. Subsequently induced cell death in tobacco cells was analyzed by lethal cell staining with Evans blue. Obtained results indicated that presence of Zn2+ at physiological concentrations can protect the cells by preventing the Al3+-induced superoxide generation and cell death. Furthermore, the regulation of the Ca2+ signaling, i.e., change in the cytosolic Ca2+ ion concentration, and the cross-talks among the elements which participate in the pathway were further explored. PMID:26648960

Specific features of aluminum nanoparticle water and wet air oxidation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lozhkomoev, Aleksandr S., E-mail: asl@ispms.tsc.ru; Glazkova, Elena A., E-mail: eagl@ispms.tsc.ru; Svarovskaya, Natalia V., E-mail: nvsv@ispms.tsc.ru

2015-10-27

The oxidation processes of the electrically exploded aluminum nanopowders in water and in wet air are examined in the paper. The morphology of the intermediate reaction products of aluminum oxidation has been studied using the transmission electron microscopy. It was shown that the aluminum nanopowder water oxidation causes the formation of the hollow spheres with mesoporous boehmite nanosheets coating. The wedge-like bayerite particles are formed during aluminum nanopowder wet air oxidation.

Contour mode resonators with acoustic reflectors

DOEpatents

Olsson, Roy H [Albuquerque, NM; Fleming, James G [Albuquerque, NM; Tuck, Melanie R [Albuquerque, NM

2008-06-10

A microelectromechanical (MEM) resonator is disclosed which has a linear or ring-shaped acoustic resonator suspended above a substrate by an acoustic reflector. The acoustic resonator can be formed with a piezoelectric material (e.g. aluminum nitride, zinc oxide or PZT), or using an electrostatically-actuated material. The acoustic reflector (also termed an acoustic mirror) uses alternating sections of a relatively low acoustic impedance Z.sub.L material and a relatively high acoustic impedance Z.sub.H material to isolate the acoustic resonator from the substrate. The MEM resonator, which can be formed on a silicon substrate with conventional CMOS circuitry, has applications for forming oscillators, rf filters, and acoustic sensors.

40 CFR 421.35 - Pretreatment standards for existing sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... (pounds per million pounds) of aluminum scrap dried Lead .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000... .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000 (c) Subpart C—Dross Washing. PSES Pollutant or... dross washed Lead 3.043 1.413 Zinc 11.090 4.565 Ammonia (as N) 1,449.000 636.000 (d) Subpart C—Demagging...

40 CFR 421.35 - Pretreatment standards for existing sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... (pounds per million pounds) of aluminum scrap dried Lead .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000... .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000 (c) Subpart C—Dross Washing. PSES Pollutant or... dross washed Lead 3.043 1.413 Zinc 11.090 4.565 Ammonia (as N) 1,449.000 636.000 (d) Subpart C—Demagging...

40 CFR 421.35 - Pretreatment standards for existing sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (pounds per million pounds) of aluminum scrap dried Lead .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000... .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000 (c) Subpart C—Dross Washing. PSES Pollutant or... dross washed Lead 3.043 1.413 Zinc 11.090 4.565 Ammonia (as N) 1,449.000 636.000 (d) Subpart C—Demagging...

40 CFR 421.35 - Pretreatment standards for existing sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... (pounds per million pounds) of aluminum scrap dried Lead .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000... .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000 (c) Subpart C—Dross Washing. PSES Pollutant or... dross washed Lead 3.043 1.413 Zinc 11.090 4.565 Ammonia (as N) 1,449.000 636.000 (d) Subpart C—Demagging...

40 CFR 421.35 - Pretreatment standards for existing sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (pounds per million pounds) of aluminum scrap dried Lead .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000... .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000 (c) Subpart C—Dross Washing. PSES Pollutant or... dross washed Lead 3.043 1.413 Zinc 11.090 4.565 Ammonia (as N) 1,449.000 636.000 (d) Subpart C—Demagging...

METAL COATED ARTICLES AND METHOD OF MAKING

DOEpatents

Eubank, L.D.

1958-08-26

A method for manufacturing a solid metallic uranium body having an integral multiple layer protective coating, comprising an inner uranium-aluminum alloy firmly bonded to the metallic uranium is presented. A third layer of silver-zinc alloy is bonded to the zinc-aluiminum layer and finally a fourth layer of lead-silver alloy is firmly bonded to the silver-zinc layer.

Determination of instream metal loads using tracer-injection and synoptic-sampling techniques in Wightman Fork, southwestern Colorado, September 1997

USGS Publications Warehouse

Ortiz, Roderick F.; Bencala, Kenneth E.

2001-01-01

Spatial determinations of the metal loads in Wightman Fork can be used to identify potential source areas to the stream. In September 1997, a chloride tracer-injection study was done concurrently with synoptic water-quality sampling in Wightman Fork near the Summitville Mine site. Discharge was determined and metal concentrations at 38 sites were used to generate mass-load profiles for dissolved aluminum, copper, iron, manganese, and zinc. The U.S. Environmental Protection Agency had previously identified these metals as contaminants of concern.Metal loads increased substantially in Wightman Fork near the Summitville Mine. A large increase occurred along a 60-meter reach that is north of the North Waste Dump and generally corresponds to a region of radial faults. Metal loading from this reach was equivalent to 50 percent or more of the dissolved aluminum, copper, iron, manganese, and zinc load upstream from the outfall of the Summitville Water Treatment Facility (SWTF). Overall, sources along the entire reach upstream from the SWTF were equivalent to 15 percent of the iron, 33 percent of the copper and manganese, 58 percent of the zinc, and 66 percent of the aluminum load leaving the mine site. The largest increases in metal loading to Wightman Fork occurred as a result of inflow from Cropsy Creek. Aluminum, iron, manganese, and zinc loads from Cropsy Creek were equivalent to about 40 percent of the specific metal load leaving the mine site. Copper, iron, and manganese loads from Cropsy Creek were nearly as large or larger than the load from sources upstream from the SWTF.

Zinc oxide nanoparticles decrease the expression and activity of plasma membrane calcium ATPase, disrupt the intracellular calcium homeostasis in rat retinal ganglion cells.

PubMed

Guo, Dadong; Bi, Hongsheng; Wang, Daoguang; Wu, Qiuxin

2013-08-01

Zinc oxide nanoparticle is one of the most important materials with diverse applications. However, it has been reported that zinc oxide nanoparticles are toxic to organisms, and that oxidative stress is often hypothesized to be an important factor in cytotoxicity mediated by zinc oxide nanoparticles. Nevertheless, the mechanism of toxicity of zinc oxide nanoparticles has not been completely understood. In this study, we investigated the cytotoxic effect of zinc oxide nanoparticles and the possible molecular mechanism involved in calcium homeostasis mediated by plasma membrane calcium ATPase in rat retinal ganglion cells. Real-time cell electronic sensing assay showed that zinc oxide nanoparticles could exert cytotoxic effect on rat retinal ganglion cells in a concentration-dependent manner; flow cytometric analysis indicated that zinc oxide nanoparticles could lead to cell damage by inducing the overproduction of reactive oxygen species. Furthermore, zinc oxide nanoparticles could also apparently decrease the expression level and their activity of plasma membrane calcium ATPase, which finally disrupt the intracellular calcium homeostasis and result in cell death. Taken together, zinc oxide nanoparticles could apparently decrease the plasma membrane calcium ATPase expression, inhibit their activity, cause the elevated intracellular calcium ion level and disrupt the intracellular calcium homeostasis. Further, the disrupted calcium homeostasis will trigger mitochondrial dysfunction, generate excessive reactive oxygen species, and finally initiate cell death. Thus, the disrupted calcium homeostasis is involved in the zinc oxide nanoparticle-induced rat retinal ganglion cell death. Copyright © 2013 Elsevier Ltd. All rights reserved.

Zinc and the modulation of redox homeostasis

PubMed Central

Oteiza, Patricia I.

2012-01-01

Zinc, a redox inactive metal, has been long viewed as a component of the antioxidant network, and growing evidence points to its involvement in redox-regulated signaling. These actions are exerted through several mechanisms based on the unique chemical and functional properties of zinc. Overall, zinc contributes to maintain the cell redox balance through different mechanisms including: i) the regulation of oxidant production and metal-induced oxidative damage; ii) the dynamic association of zinc with sulfur in protein cysteine clusters, from which the metal can be released by nitric oxide, peroxides, oxidized glutathione and other thiol oxidant species; iii) zinc-mediated induction of the zinc-binding protein metallothionein, which releases the metal under oxidative conditions and act per se scavenging oxidants; iv) the involvement of zinc in the regulation of glutathione metabolism and of the overall protein thiol redox status; and v) a direct or indirect regulation of redox signaling. Findings of oxidative stress, altered redox signaling, and associated cell/tissue disfunction in cell and animal models of zinc deficiency, stress the relevant role of zinc in the preservation of cell redox homeostasis. However, while the participation of zinc in antioxidant protection, redox sensing, and redox-regulated signaling is accepted, the involved molecules, targets and mechanisms are still partially known and the subject of active research. PMID:22960578

40 CFR 467.62 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ALUMINUM FORMING POINT SOURCE CATEGORY Drawing With Emulsions... off-lbs) of aluminum drawn with emulsions or soaps Chromium 0.205 0.084 Cyanide 0.135 0.056 Zinc 0.680...

40 CFR 467.62 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ALUMINUM FORMING POINT SOURCE CATEGORY Drawing With Emulsions... off-lbs) of aluminum drawn with emulsions or soaps Chromium 0.205 0.084 Cyanide 0.135 0.056 Zinc 0.680...

40 CFR 467.22 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ALUMINUM FORMING POINT SOURCE CATEGORY Rolling With Emulsions...-lbs) of aluminum rolled with emulsions Chromium 0.057 0.024 Cyanide 0.038 0.016 Zinc 0.19 0.079...

40 CFR 467.22 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2011 CFR

2011-07-01

... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ALUMINUM FORMING POINT SOURCE CATEGORY Rolling With Emulsions...-lbs) of aluminum rolled with emulsions Chromium 0.057 0.024 Cyanide 0.038 0.016 Zinc 0.19 0.079...

40 CFR 467.63 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2012 CFR

2012-07-01

...) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ALUMINUM FORMING POINT SOURCE CATEGORY Drawing With Emulsions...-lbs) of aluminum drawn with emulsions or soaps Chromium 0.205 0.084 Cyanide 0.135 0.056 Zinc 0.681 0...

40 CFR 467.63 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2014 CFR

2014-07-01

...) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ALUMINUM FORMING POINT SOURCE CATEGORY Drawing With Emulsions...-lbs) of aluminum drawn with emulsions or soaps Chromium 0.205 0.084 Cyanide 0.135 0.056 Zinc 0.681 0...

Surface-Water Hydrology and Quality at the Pike Hill Superfund Site, Corinth, Vermont, October 2004 to December 2005

USGS Publications Warehouse

Kiah, Richard G.; Deacon, Jeffrey R.; Piatak, Nadine M.; Seal, Robert R.; Coles, James F.; Hammarstrom, Jane M.

2007-01-01

The hydrology and quality of surface water in and around the Pike Hill Brook watershed, in Corinth, Vermont, was studied from October 2004 to December 2005 by the U.S. Geological Survey in cooperation with the U.S. Environmental Protection Agency (USEPA). Pike Hill was mined intermittently for copper from 1847 to 1919 and the site is known to be contributing trace elements and acidity to Pike Hill Brook and an unnamed tributary to Cookville Brook. The site has been listed as a Superfund site since 2004. Streamflow, specific conductance, pH, and water temperature were measured continuously and monthly at three sites on Pike Hill Brook to determine the variation in these parameters over an annual cycle. Synoptic water-quality sampling was done at 10 stream sites in October 2004, April 2005, and June 2005 and at 13 stream sites in August 2005 to characterize the quality of surface water in the watershed on a seasonal and spatial basis, as well as to assess the effects of wetlands on water quality. Samples for analysis of benthic macroinvertebrate populations were collected at 11 stream sites in August 2005. Water samples were analyzed for 5 major ions and 32 trace elements. Concentrations of trace elements at sites in the Pike Hill Brook watershed exceeded USEPA National Recommended Water Quality Criteria acute and chronic toxicity standards for aluminum, iron, cadmium, copper, and zinc. Concentrations of copper exceeded the chronic criteria in an unnamed tributary to Cookville Brook in one sample. Concentrations of sulfate, calcium, aluminum, iron, cadmium, copper, and zinc decreased with distance from a site directly downstream from the mine (site 1), as a result of dilution and through sorption and precipitation of the trace elements. Maximum concentrations of aluminum, iron, cadmium, copper, and zinc were observed during spring snowmelt. Concentrations of sulfate, calcium, cadmium, copper, and zinc, and instantaneous loads of calcium and aluminum were statistically different (p<0.05) among the three continuously monitored sites (sites 1, 4, and 5). Instantaneous loads of aluminum, iron, and copper decreased by one to three orders of magnitude from site 1 to a site 1.1 mi downstream (site 4). Instantaneous loads of sulfate were similar between sites 1, 4, and at a site 3 mi downstream (site 5). Instantaneous loads of cadmium and zinc were similar between sites 1 and 4, and loads of iron and copper were similar between sites 4 and 5. Loads of chemical constituents were compared at site 1 (closest to the mine waste piles) and site 5 (near the mouth of Pike Hill Brook and below a majority of the wetlands). Annually, the loads of dissolved cadmium and zinc at site 1 were about five times greater than loads at site 5, and the load of dissolved copper at site 1 was about 17 times greater than at site 5. The ratio of loads for dissolved cadmium, copper, and zinc to total cadmium, copper, and zinc at site 1 was about 1. Samples collected in Pike Hill Brook upstream and downstream from the wetlands during low flows in August 2005 showed that oxidation of ferrous iron and precipitation of iron-hydroxides were probably not affecting trace metals in the wetlands through sorption; however, a significant portion of the iron entering the wetlands was in particulate form and may have transported sorbed copper and other trace metals. Thus, aerobic activity in the wetlands was probably not affecting metal cycling in the watershed. Concentrations and loads of sulfate may be unlikely to define unequivocally the role of the wetlands with regard to anaerobic bacterial sulfate reduction; however, bacterial sulfate removal may have affected loads of sulfate. Loads of copper increased downstream from the wetlands and may reflect the reductive dissolution of ferric hydroxide particulates in anaerobic parts of the wetlands.Concentrations of dissolved iron increased downstream from the wetlands. The most apparent effects on the macroinvertebr

Incorporation of zinc oxide nanoparticles into chitosan-collagen 3D porous scaffolds: Effect on morphology, mechanical properties and cytocompatibility of 3D porous scaffolds.

PubMed

Ullah, Saleem; Zainol, Ismail; Idrus, Ruszymah Hj

2017-11-01

The zinc oxide nanoparticles (particles size <50nm) incorporated into chitosan-collagen 3D porous scaffolds and investigated the effect of zinc oxide nanoparticles incorporation on microstructure, mechanical properties, biodegradation and cytocompatibility of 3D porous scaffolds. The 0.5%, 1.0%, 2.0% and 4.0% zinc oxide nanoparticles chitosan-collagen 3D porous scaffolds were fabricated via freeze-drying technique. The zinc oxide nanoparticles incorporation effects consisting in chitosan-collagen 3D porous scaffolds were investigated by mechanical and swelling tests, and effect on the morphology of scaffolds examined microscopically. The biodegradation and cytocompatibility tests were used to investigate the effects of zinc oxide nanoparticles incorporation on the ability of scaffolds to use for tissue engineering application. The mean pore size and swelling ratio of scaffolds were decreased upon incorporation of zinc oxide nanoparticles however, the porosity, tensile modulus and biodegradation rate were increased upon incorporation of zinc oxide nanoparticles. In vitro culture of human fibroblasts and keratinocytes showed that the zinc oxide nanoparticles facilitated cell adhesion, proliferation and infiltration of chitosan-collagen 3D porous scaffolds. It was found that the zinc oxide nanoparticles incorporation enhanced porosity, tensile modulus and cytocompatibility of chitosan-collagen 3D porous scaffolds. Copyright © 2017 Elsevier B.V. All rights reserved.

Oocyte exposure to ZnO nanoparticles inhibits early embryonic development through the γ-H2AX and NF-κB signaling pathways.

PubMed

Liu, Jing; Zhao, Yong; Ge, Wei; Zhang, Pengfei; Liu, Xinqi; Zhang, Weidong; Hao, Yanan; Yu, Shuai; Li, Lan; Chu, Meiqiang; Min, Lingjiang; Zhang, Hongfu; Shen, Wei

2017-06-27

The impacts of zinc oxide nanoparticles on embryonic development following oocyte stage exposure are unknown and the underlying mechanisms are sparsely understood. In the current investigation, intact nanoparticles were detected in ovarian tissue in vivo and cultured cells in vitro under zinc oxide nanoparticles treatment. Zinc oxide nanoparticles exposure during the oocyte stage inhibited embryonic development. Notably, in vitro culture data closely matched in vivo embryonic data, in that the impairments caused by Zinc oxide nanoparticles treatment passed through cell generations; and both gamma-H2AX and NF-kappaB pathways were involved in zinc oxide nanoparticles caused embryo-toxicity. Copper oxide and silicon dioxide nanoparticles have been used to confirm that particles are important for the toxicity of zinc oxide nanoparticles. The toxic effects of zinc oxide nanoparticles emanate from both intact nanoparticles and Zn2+. Our investigation along with others suggests that zinc oxide nanoparticles are toxic to the female reproductive system [ovaries (oocytes)] and subsequently embryo-toxic and that precaution should be taken regarding human exposure to their everyday use.

Oocyte exposure to ZnO nanoparticles inhibits early embryonic development through the γ-H2AX and NF-κB signaling pathways

PubMed Central

Liu, Jing; Zhao, Yong; Ge, Wei; Zhang, Pengfei; Liu, Xinqi; Zhang, Weidong; Hao, Yanan; Yu, Shuai; Li, Lan; Chu, Meiqiang; Min, Lingjiang; Zhang, Hongfu; Shen, Wei

2017-01-01

The impacts of zinc oxide nanoparticles on embryonic development following oocyte stage exposure are unknown and the underlying mechanisms are sparsely understood. In the current investigation, intact nanoparticles were detected in ovarian tissue in vivo and cultured cells in vitro under zinc oxide nanoparticles treatment. Zinc oxide nanoparticles exposure during the oocyte stage inhibited embryonic development. Notably, in vitro culture data closely matched in vivo embryonic data, in that the impairments caused by Zinc oxide nanoparticles treatment passed through cell generations; and both gamma-H2AX and NF-kappaB pathways were involved in zinc oxide nanoparticles caused embryo-toxicity. Copper oxide and silicon dioxide nanoparticles have been used to confirm that particles are important for the toxicity of zinc oxide nanoparticles. The toxic effects of zinc oxide nanoparticles emanate from both intact nanoparticles and Zn2+. Our investigation along with others suggests that zinc oxide nanoparticles are toxic to the female reproductive system [ovaries (oocytes)] and subsequently embryo-toxic and that precaution should be taken regarding human exposure to their everyday use. PMID:28487501

Augmentation of aluminum-induced oxidative stress in rat cerebrum by presence of pro-oxidant (graded doses of ethanol) exposure.

PubMed

Nayak, Prasunpriya; Sharma, Shiv Bhushan; Chowdary, Nadella Vijaya Subbaraya

2010-11-01

Both aluminum and ethanol are pro-oxidants and neurotoxic. Considering the possibilities of co-exposure and sharing mechanisms of producing neurotoxicity, the present study was planned to identify the level of aluminum-induced oxidative stress in altered pro-oxidant (ethanol exposure) status of cerebrum. Male rats were coexposed to aluminum and ethanol for 4 weeks. After the exposure period, cerebral levels of protein, reduced glutathione (GSH), lipid peroxidation (TBARS) were measured. Activities of catalase, superoxide dismutase (SOD), glutathione reductase (GR) and glutathione perioxidase (GPx) of cerebrum were estimated. In most of the cases significant correlations were observed between the alterations and graded ethanol doses, suggesting a dose-dependency in pushing the oxidant equilibrium toward pro-oxidants. Aluminum is found to influence significantly all the studied parameters of oxidative stress. Likewise, ethanol also influenced these parameters significantly, except GR, while the interaction between ethanol and aluminum could significantly influence only the GSH content and GR activity of cerebrum. Present study demonstrate that coexposure of aluminum with pro-oxidant might favor development of aluminum-induced oxidative stress in cerebrum. This observation might be helpful in understanding of mechanism of neurodegenerative disorders and ameliorate them.

21 CFR 182.8991 - Zinc oxide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Zinc oxide. 182.8991 Section 182.8991 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8991 Zinc oxide. (a) Product. Zinc oxide. (b) Conditions of use...

21 CFR 182.8991 - Zinc oxide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Zinc oxide. 182.8991 Section 182.8991 Food and... CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8991 Zinc oxide. (a) Product. Zinc oxide. (b) Conditions of use. This substance is generally recognized as safe when used in...

21 CFR 582.5991 - Zinc oxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Zinc oxide. 582.5991 Section 582.5991 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5991 Zinc oxide. (a) Product. Zinc oxide. (b) Conditions of use. This substance is generally...

21 CFR 182.8991 - Zinc oxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Zinc oxide. 182.8991 Section 182.8991 Food and... CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8991 Zinc oxide. (a) Product. Zinc oxide. (b) Conditions of use. This substance is generally recognized as safe when used in...

21 CFR 582.5991 - Zinc oxide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Zinc oxide. 582.5991 Section 582.5991 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS... 1 § 582.5991 Zinc oxide. (a) Product. Zinc oxide. (b) Conditions of use. This substance is generally...

40 CFR 421.33 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2011 CFR

2011-07-01

... .000 .000 Aluminum .000 .000 Ammonia (as N) .000 .000 (b) Subpart C—Scrap Screening and Milling. BAT... Aluminum .000 .000 Ammonia (as N) .000 .000 (c) Subpart C—Dross Washing. BAT Effluent Limitations Pollutant... pounds) of dross washed Lead 3.043 1.413 Zinc 11.090 4.565 Aluminum 66.410 29.450 Ammonia (as N) 1,449...

40 CFR 421.33 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2012 CFR

2012-07-01

... .000 .000 Aluminum .000 .000 Ammonia (as N) .000 .000 (b) Subpart C—Scrap Screening and Milling. BAT... Aluminum .000 .000 Ammonia (as N) .000 .000 (c) Subpart C—Dross Washing. BAT Effluent Limitations Pollutant... pounds) of dross washed Lead 3.043 1.413 Zinc 11.090 4.565 Aluminum 66.410 29.450 Ammonia (as N) 1,449...

40 CFR 421.33 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... .000 .000 Aluminum .000 .000 Ammonia (as N) .000 .000 (b) Subpart C—Scrap Screening and Milling. BAT... Aluminum .000 .000 Ammonia (as N) .000 .000 (c) Subpart C—Dross Washing. BAT Effluent Limitations Pollutant... pounds) of dross washed Lead 3.043 1.413 Zinc 11.090 4.565 Aluminum 66.410 29.450 Ammonia (as N) 1,449...

40 CFR 467.23 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2013 CFR

2013-07-01

...) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ALUMINUM FORMING POINT SOURCE CATEGORY Rolling With Emulsions... rolled with emulsions Chromium 0.057 0.024 Cyanide 0.038 0.016 Zinc 0.19 0.079 Aluminum 0.84 0.42 Subpart...

40 CFR 467.23 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2011 CFR

2011-07-01

...) EFFLUENT GUIDELINES AND STANDARDS ALUMINUM FORMING POINT SOURCE CATEGORY Rolling With Emulsions Subcategory... rolled with emulsions Chromium 0.057 0.024 Cyanide 0.038 0.016 Zinc 0.19 0.079 Aluminum 0.84 0.42 Subpart...

40 CFR 467.23 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2012 CFR

2012-07-01

...) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ALUMINUM FORMING POINT SOURCE CATEGORY Rolling With Emulsions... rolled with emulsions Chromium 0.057 0.024 Cyanide 0.038 0.016 Zinc 0.19 0.079 Aluminum 0.84 0.42 Subpart...

40 CFR 467.23 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2014 CFR

2014-07-01

...) EFFLUENT GUIDELINES AND STANDARDS (CONTINUED) ALUMINUM FORMING POINT SOURCE CATEGORY Rolling With Emulsions... rolled with emulsions Chromium 0.057 0.024 Cyanide 0.038 0.016 Zinc 0.19 0.079 Aluminum 0.84 0.42 Subpart...

ZnO nanorod arrays and direct wire bonding on GaN surfaces for rapid fabrication of antireflective, high-temperature ultraviolet sensors

NASA Astrophysics Data System (ADS)

So, Hongyun; Senesky, Debbie G.

2016-11-01

Rapid, cost-effective, and simple fabrication/packaging of microscale gallium nitride (GaN) ultraviolet (UV) sensors are demonstrated using zinc oxide nanorod arrays (ZnO NRAs) as an antireflective layer and direct bonding of aluminum wires to the GaN surface. The presence of the ZnO NRAs on the GaN surface significantly reduced the reflectance to less than 1% in the UV and 4% in the visible light region. As a result, the devices fabricated with ZnO NRAs and mechanically stable aluminum bonding wires (pull strength of 3-5 gf) showed higher sensitivity (136.3% at room temperature and 148.2% increase at 250 °C) when compared with devices with bare (uncoated) GaN surfaces. In addition, the devices demonstrated reliable operation at high temperatures up to 300 °C, supporting the feasibility of simple and cost-effective UV sensors operating with higher sensitivity in high-temperature conditions, such as in combustion, downhole, and space exploration applications.

21 CFR 73.2991 - Zinc oxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Zinc oxide. 73.2991 Section 73.2991 Food and Drugs... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2991 Zinc oxide. (a) Identity and specifications. The color additive zinc oxide shall conform in identity and specifications to the requirements of § 73.1991...

Electrocontact material based on silver dispersion-strengthened by nickel, titanium, and zinc oxides

NASA Astrophysics Data System (ADS)

Zeer, G. M.; Zelenkova, E. G.; Belousov, O. V.; Beletskii, V. V.; Nikolaev, S. V.; Ledyaeva, O. N.

2017-09-01

Samples of a composite electrocontact material based on silver strengthened by the dispersed phases of zinc and titanium oxides have been investigated by the electron microscopy and energy dispersive X-ray spectroscopy. A uniform distribution of the oxide phases containing 2 wt % zinc oxide in the initial charge has been revealed. The increase in the amount of zinc oxide leads to an increase of the size of the oxide phases. It has been shown that at the zinc oxide content of 2 wt %, the minimum wear is observed in the process of electroerosion tests; at 3 wt %, an overheating and welding of the contacts are observed.

Time-resolved fluorescence and ultrafast energy transfer in a zinc (hydr)oxide-graphite oxide mesoporous composite

NASA Astrophysics Data System (ADS)

Secor, Jeff; Narinesingh, Veeshan; Seredych, Mykola; Giannakoudakis, Dimitrios A.; Bandosz, Teresa; Alfano, Robert R.

2015-01-01

Ultrafast energy decay kinetics of a zinc (hydr)oxide-graphite oxide (GO) composite is studied via time-resolved fluorescence spectroscopy. The time-resolved emission is spectrally decomposed into emission regions originating from the zinc (hydr)oxide optical gap, surface, and defect states of the composite material. The radiative lifetime of deep red emission becomes an order of magnitude longer than that of GO alone while the radiative lifetime of the zinc optical gap is shortened in the composite. An energy transfer scheme from the zinc (hydr)oxide to GO is considered.

Formulation and method for preparing gels comprising hydrous aluminum oxide

DOEpatents

Collins, Jack L.

2014-06-17

Formulations useful for preparing hydrous aluminum oxide gels contain a metal salt including aluminum, an organic base, and a complexing agent. Methods for preparing gels containing hydrous aluminum oxide include heating a formulation to a temperature sufficient to induce gel formation, where the formulation contains a metal salt including aluminum, an organic base, and a complexing agent.

Active sites for CO 2 hydrogenation to methanol on Cu/ZnO catalysts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kattel, Shyam; Ramírez, Pedro J.; Chen, Jingguang G.

The active sites over commercial copper/zinc oxide/aluminum oxide (Cu/ZnO/Al 2O 3) catalysts for carbon dioxide (CO 2) hydrogenation to methanol, the Zn-Cu bimetallic sites or ZnO-Cu interfacial sites, have recently been the subject of intense debate. Here, we report a direct comparison between the activity of ZnCu and ZnO/Cu model catalysts for methanol synthesis. By combining x-ray photoemission spectroscopy, density functional theory, and kinetic Monte Carlo simulations, we can identify and characterize the reactivity of each catalyst. Both experimental and theoretical results agree that ZnCu undergoes surface oxidation under the reaction conditions so that surface Zn transforms into ZnO andmore » allows ZnCu to reach the activity of ZnO/Cu with the same Zn coverage. These results highlight a synergy of Cu and ZnO at the interface that facilitates methanol synthesis via formate intermediates.« less

Active sites for CO 2 hydrogenation to methanol on Cu/ZnO catalysts

DOE PAGES

Kattel, Shyam; Ramírez, Pedro J.; Chen, Jingguang G.; ...

2017-03-23

The active sites over commercial copper/zinc oxide/aluminum oxide (Cu/ZnO/Al 2O 3) catalysts for carbon dioxide (CO 2) hydrogenation to methanol, the Zn-Cu bimetallic sites or ZnO-Cu interfacial sites, have recently been the subject of intense debate. Here, we report a direct comparison between the activity of ZnCu and ZnO/Cu model catalysts for methanol synthesis. By combining x-ray photoemission spectroscopy, density functional theory, and kinetic Monte Carlo simulations, we can identify and characterize the reactivity of each catalyst. Both experimental and theoretical results agree that ZnCu undergoes surface oxidation under the reaction conditions so that surface Zn transforms into ZnO andmore » allows ZnCu to reach the activity of ZnO/Cu with the same Zn coverage. These results highlight a synergy of Cu and ZnO at the interface that facilitates methanol synthesis via formate intermediates.« less

Morphological Control of Metal Oxide-Doped Zinc Oxide and Application to Cosmetics

NASA Astrophysics Data System (ADS)

Goto, Takehiro; Yin, Shu; Sato, Tsugio; Tanaka, Takumi

2012-06-01

Zinc oxide shows excellent transparency and ultraviolet radiation shielding ability, and is used for various cosmetics.1-3 However, it possesses high catalytic activity and lower dispersibility. Therefore, spherical particles of zinc oxide have been synthesized by soft solution reaction using zinc nitrate, ethylene glycol, sodium hydroxide and triethanolamine as starting materials. After dissolving these compounds in water, the solution was heated at 90°C for 1 h to form almost mono-dispersed spherical zinc oxide particles. The particle size changed depending on zinc ion concentration, ethylene glycol concentration and so on. Furthermore, with doping some metal ions, the phtocatalytic activity could be decreased. The obtained monodispersed metal ion-doped spherical zinc oxides showed excellent UV shielding ability and low photocatalytic activity. Therefore, they are expected to be used as cosmetics ingredients.

40 CFR 467.63 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2011 CFR

2011-07-01

...) EFFLUENT GUIDELINES AND STANDARDS ALUMINUM FORMING POINT SOURCE CATEGORY Drawing With Emulsions or Soaps... emulsions or soaps Chromium 0.205 0.084 Cyanide 0.135 0.056 Zinc 0.681 0.285 Aluminum 3.00 1.49 Subpart F...

40 CFR 467.52 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) EFFLUENT GUIDELINES AND STANDARDS ALUMINUM FORMING POINT SOURCE CATEGORY Drawing With Neat Oils... drawn with neat oils Chromium 0.022 0.0090 Cyanide 0.015 0.0050 Zinc 0.073 0.031 Aluminum 0.32 0.160 Oil...

Aluminum-dependent regulation of intracellular silicon in the aquatic invertebrate Lymnaea stagnalis

PubMed Central

Desouky, Mahmoud; Jugdaohsingh, Ravin; McCrohan, Catherine R.; White, Keith N.; Powell, Jonathan J.

2002-01-01

Silicon is essential for some plants, diatoms, and sponges but, in higher animals, its endogenous regulation has not been demonstrated. Silicate ions may be natural ligands for aluminum and here we show that, in the freshwater snail (Lymnaea stagnalis), intracellular silicon seems specifically up-regulated in response to sublethal aluminum exposure. X-ray microanalysis showed that exposure of snails to low levels of aluminum led to its accumulation in lysosomal granules, accompanied by marked up-regulation of silicon. Increased lysosomal levels of silicon were a specific response to aluminum because cadmium and zinc had no such effect. Furthermore, intra-lysosomal sulfur from metallothionein and other sulfur-containing ligands was increased after exposure to cadmium and zinc but not aluminum. To ensure that these findings indicated a specific in vivo response, and not ex vivo formation of hydroxy-aluminosilicates (HAS) from added aluminum (555 μg/liter) and water-borne silicon (43 μg/liter), two further studies were undertaken. In a ligand competition assay the lability of aluminum (527 μg/liter) was completely unaffected by the presence of silicon (46 μg/liter), suggesting the absence of HAS. In addition, exogenous silicon (6.5 mg/liter), added to the water column to promote formation of HAS, caused a decrease in lysosomal aluminum accumulation, showing that uptake of HAS would not explain the loading of aluminum into lysosomal granules. These findings, and arguments on the stability, lability, and kinetics of aluminum–silicate interactions, suggest that a silicon-specific mechanism exists for the in vivo detoxification of aluminum, which provides regulatory evidence of silicon in a multicellular organism. PMID:11891333

21 CFR 73.2991 - Zinc oxide.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Zinc oxide. 73.2991 Section 73.2991 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2991 Zinc oxide. (a) Identity and specifications. The color additive zinc oxide shall conform in...

21 CFR 73.2991 - Zinc oxide.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Zinc oxide. 73.2991 Section 73.2991 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2991 Zinc oxide. (a) Identity and specifications. The color additive zinc oxide shall conform in...

21 CFR 73.1991 - Zinc oxide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Zinc oxide. 73.1991 Section 73.1991 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1991 Zinc oxide. (a) Identity. (1) The color additive zinc oxide is a white or yellow-white amorphous...

21 CFR 73.1991 - Zinc oxide.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Zinc oxide. 73.1991 Section 73.1991 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1991 Zinc oxide. (a) Identity. (1) The color additive zinc oxide is a white or yellow-white amorphous...

21 CFR 73.1991 - Zinc oxide.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Zinc oxide. 73.1991 Section 73.1991 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1991 Zinc oxide. (a) Identity. (1) The color additive zinc oxide is a white or yellow-white amorphous...

Analysis of cellular responses of macrophages to zinc ions and zinc oxide nanoparticles: a combined targeted and proteomic approach.

PubMed

Triboulet, Sarah; Aude-Garcia, Catherine; Armand, Lucie; Gerdil, Adèle; Diemer, Hélène; Proamer, Fabienne; Collin-Faure, Véronique; Habert, Aurélie; Strub, Jean-Marc; Hanau, Daniel; Herlin, Nathalie; Carrière, Marie; Van Dorsselaer, Alain; Rabilloud, Thierry

2014-06-07

Two different zinc oxide nanoparticles, as well as zinc ions, are used to study the cellular responses of the RAW 264 macrophage cell line. A proteomic screen is used to provide a wide view of the molecular effects of zinc, and the most prominent results are cross-validated by targeted studies. Furthermore, the alteration of important macrophage functions (e.g. phagocytosis) by zinc is also investigated. The intracellular dissolution/uptake of zinc is also studied to further characterize zinc toxicity. Zinc oxide nanoparticles dissolve readily in the cells, leading to high intracellular zinc concentrations, mostly as protein-bound zinc. The proteomic screen reveals a rather weak response in the oxidative stress response pathway, but a strong response both in the central metabolism and in the proteasomal protein degradation pathway. Targeted experiments confirm that carbohydrate catabolism and proteasome are critical determinants of sensitivity to zinc, which also induces DNA damage. Conversely, glutathione levels and phagocytosis appear unaffected at moderately toxic zinc concentrations.

Air-Impregnated Nanoporous Anodic Aluminum Oxide Layers for Enhancing the Corrosion Resistance of Aluminum.

PubMed

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.

The Proof of the ``Vortex Theory of Matter''

NASA Astrophysics Data System (ADS)

Moon, Russell

2009-11-01

According to the Vortex Theory, protons and electrons are three-dimensional holes connected by fourth-dimensional vortices. It was further theorized that when photons are absorbed then readmitted by atoms, the photon is absorbed into the proton, moves through the fourth-dimensional vortex, then reemerges back into three-dimensional space through the electron. To prove this hypothesis, an experiment was conducted using a hollow aluminum sphere containing a powerful permanent magnet suspended directly above a zinc plate. Ultraviolet light was then shined upon the zinc. The zinc emits electrons via the photoelectric effect that are attracted to the surface of the aluminum sphere. The sphere was removed from above the zinc plate and repositioned above a sensitive infrared digital camera in another room. The ball and camera were placed within a darkened box inside a Faraday cage. Light was shined upon the zinc plate and the picture taken by the camera was observed. When the light was turned on above the zinc plate in one room, the camera recorded increased light coming from the surface of the sphere within the other room; when the light was turned off, the intensity of the infrared light coming from the surface of the sphere was suddenly diminished. Five other tests were then performed to eliminate other possible explanations such as quantum-entangled electrons.

The Proof of the ``Vortex Theory of Matter''

NASA Astrophysics Data System (ADS)

Gridnev, Konstantin; Moon, Russell; Vasiliev, Victor

2009-11-01

According to the Vortex Theory, protons and electrons are three-dimensional holes connected by fourth-dimensional vortices. It was further theorized that when photons are absorbed then readmitted by atoms, the photon is absorbed into the proton, moves through the fourth-dimensional vortex, then reemerges back into three-dimensional space through the electron^2. To prove this hypothesis, an experiment was conducted using a hollow aluminum sphere containing a powerful permanent magnet suspended directly above a zinc plate. Ultraviolet light was then shined upon the zinc. The zinc emits electrons via the photoelectric effect that are attracted to the surface of the aluminum sphere. The sphere was removed from above the zinc plate and repositioned above a sensitive infrared digital camera in another room. The ball and camera were placed within a darkened box inside a Faraday cage. Light was shined upon the zinc plate and the picture taken by the camera was observed. When the light was turned on above the zinc plate in one room, the camera recorded increased light coming from the surface of the sphere within the other room; when the light was turned off, the intensity of the infrared light coming from the surface of the sphere was suddenly diminished. Five other tests were then performed to eliminate other possible explanations such as quantum-entangled electrons.

The Proof of the ``Vortex Theory of Matter''

NASA Astrophysics Data System (ADS)

Gridnev, Konstantin; Moon, Russell; Vasiliev, Victor

2009-10-01

According to the Vortex Theory, protons and electrons are three-dimensional holes connected by fourth-dimensional vortices. It was further theorized that when photons are absorbed then readmitted by atoms, the photon is absorbed into the proton, moves through the fourth-dimensional vortex, then reemerges back into three-dimensional space through the electron^2. To prove this hypothesis, an experiment was conducted using a hollow aluminum sphere containing a powerful permanent magnet suspended directly above a zinc plate. Ultraviolet light was then shined upon the zinc. The zinc emits electrons via the photoelectric effect that are attracted to the surface of the aluminum sphere. The sphere was removed from above the zinc plate and repositioned above a sensitive infrared digital camera in another room. The ball and camera were placed within a darkened box inside a Faraday cage. Light was shined upon the zinc plate and the picture taken by the camera was observed. When the light was turned on above the zinc plate in one room, the camera recorded increased light coming from the surface of the sphere within the other room; when the light was turned off, the intensity of the infrared light coming from the surface of the sphere was suddenly diminished. Five other tests were then performed to eliminate other possible explanations such as quantum-entangled electrons.

The Proof of the ``Vortex Theory of Matter''

NASA Astrophysics Data System (ADS)

Moon, Russell; Gridnev, Konstantin; Vasiliev, Victor

2010-02-01

According to the Vortex Theory, protons and electrons are three-dimensional holes connected by fourth-dimensional vortices. It was further theorized that when photons are absorbed then readmitted by atoms, the photon is absorbed into the proton, moves through the fourth-dimensional vortex, then reemerges back into three-dimensional space through the electron. To prove this hypothesis, an experiment was conducted using a hollow aluminum sphere containing a powerful permanent magnet suspended directly above a zinc plate. Ultraviolet light was then shined upon the zinc. The zinc emits electrons via the photoelectric effect that are attracted to the surface of the aluminum sphere. The sphere was removed from above the zinc plate and repositioned above a sensitive infrared digital camera in another room. The ball and camera were placed within a darkened box inside a Faraday cage. Light was shined upon the zinc plate and the picture taken by the camera was observed. When the light was turned on above the zinc plate in one room, the camera recorded increased light coming from the surface of the sphere within the other room; when the light was turned off, the intensity of the infrared light coming from the surface of the sphere was suddenly diminished. Five other tests were then performed to eliminate other possible explanations such as quantum-entangled electrons. )

Zinc Absorption by Young Adults from Supplemental Zinc Citrate Is Comparable with That from Zinc Gluconate and Higher than from Zinc Oxide123

PubMed Central

Wegmüller, Rita; Tay, Fabian; Zeder, Christophe; Brnić, Marica; Hurrell, Richard F.

2014-01-01

The water-soluble zinc salts gluconate, sulfate, and acetate are commonly used as supplements in tablet or syrup form to prevent zinc deficiency and to treat diarrhea in children in combination with oral rehydration. Zinc citrate is an alternative compound with high zinc content, slightly soluble in water, which has better sensory properties in syrups but no absorption data in humans. We used the double-isotope tracer method with 67Zn and 70Zn to measure zinc absorption from zinc citrate given as supplements containing 10 mg of zinc to 15 healthy adults without food and compared absorption with that from zinc gluconate and zinc oxide (insoluble in water) using a randomized, double-masked, 3-way crossover design. Median (IQR) fractional absorption of zinc from zinc citrate was 61.3% (56.6–71.0) and was not different from that from zinc gluconate with 60.9% (50.6–71.7). Absorption from zinc oxide at 49.9% (40.9–57.7) was significantly lower than from both other supplements (P < 0.01). Three participants had little or no absorption from zinc oxide. We conclude that zinc citrate, given as a supplement without food, is as well absorbed by healthy adults as zinc gluconate and may thus be a useful alternative for preventing zinc deficiency and treating diarrhea. The more insoluble zinc oxide is less well absorbed when given as a supplement without food and may be minimally absorbed by some individuals. This trial was registered at clinicaltrials.gov as NCT01576627. PMID:24259556

Novel Nanometric Superstructures for Radiation and Magnetic Sensing

DTIC Science & Technology

2007-05-22

AAO Anodic aluminum oxide AFM Atomic force microscope AFRL Air...Ni nanowires in a 2 µm AAO film after aluminum oxide was partially dissolved; (c) part of the Bi nanowires in a 25 µm AAO template after aluminum ...conditions [R3]. In this process, after removing the thick aluminum oxide film obtained from the first long anodization , the aluminum surface

Morphology and Mechanism of Benign Inhibitors

DTIC Science & Technology

2012-07-01

AAO resulting in much lower SLD. ....... 84 xiv List of Acronyms AA: Aluminum alloy; AAO : Anodic aluminum oxide ; AMCC: Advanced Materials...shown, we achieved excellent vanadate, trivalent chromium process (TCP) and anodic aluminum oxide ( AAO ) films. We also tried Ce but Ce did not form a...we also initiated the study of anodizing of aluminum . According to the literature anodic aluminum oxide

Near-perfect broadband absorption from hyperbolic metamaterial nanoparticles

NASA Astrophysics Data System (ADS)

Riley, Conor T.; Smalley, Joseph S. T.; Brodie, Jeffrey R. J.; Fainman, Yeshaiahu; Sirbuly, Donald J.; Liu, Zhaowei

2017-02-01

Broadband absorbers are essential components of many light detection, energy harvesting, and camouflage schemes. Current designs are either bulky or use planar films that cause problems in cracking and delamination during flexing or heating. In addition, transferring planar materials to flexible, thin, or low-cost substrates poses a significant challenge. On the other hand, particle-based materials are highly flexible and can be transferred and assembled onto a more desirable substrate but have not shown high performance as an absorber in a standalone system. Here, we introduce a class of particle absorbers called transferable hyperbolic metamaterial particles (THMMP) that display selective, omnidirectional, tunable, broadband absorption when closely packed. This is demonstrated with vertically aligned hyperbolic nanotube (HNT) arrays composed of alternating layers of aluminum-doped zinc oxide and zinc oxide. The broadband absorption measures >87% from 1,200 nm to over 2,200 nm with a maximum absorption of 98.1% at 1,550 nm and remains large for high angles. Furthermore, we show the advantages of particle-based absorbers by transferring the HNTs to a polymer substrate that shows excellent mechanical flexibility and visible transparency while maintaining near-perfect absorption in the telecommunications region. In addition, other material systems and geometries are proposed for a wider range of applications.

Regeneration of zinc halide catalyst used in the hydrocracking of polynuclear hydrocarbons

DOEpatents

Gorin, Everett

1978-01-01

Improved recovery of spent molten zinc halide hydro-cracking catalyst is achieved in the oxidative vapor phase regeneration thereof by selective treatment of the zinc oxide carried over by the effluent vapors from the regeneration zone with hydrogen halide gas under conditions favoring the reaction of the zinc oxide with the hydrogen halide, whereby regenerated zinc halide is recovered in a solids-free state with little loss of zinc values.

40 CFR 467.33 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2012 CFR

2012-07-01

... 1.25 Aluminum 13.10 6.52 Subpart C Solution Heat Treatment Contact Cooling Water Pollutant or....24 Cyanide 0.39 0.16 Zinc 1.94 0.81 Aluminum 8.55 4.26 Subpart C Press Heat Treatment Contact Cooling...

40 CFR 467.33 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2014 CFR

2014-07-01

... 1.25 Aluminum 13.10 6.52 Subpart C Solution Heat Treatment Contact Cooling Water Pollutant or....24 Cyanide 0.39 0.16 Zinc 1.94 0.81 Aluminum 8.55 4.26 Subpart C Press Heat Treatment Contact Cooling...

40 CFR 467.33 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2013 CFR

2013-07-01

... 1.25 Aluminum 13.10 6.52 Subpart C Solution Heat Treatment Contact Cooling Water Pollutant or....24 Cyanide 0.39 0.16 Zinc 1.94 0.81 Aluminum 8.55 4.26 Subpart C Press Heat Treatment Contact Cooling...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Herkovits, J.; Herkovits, F.D.; Perez-Coll

As a result of their aquatic embryonic and larval development, many species of amphibians are potentially affected by adverse environmental conditions. In this study the possibility of reducing the lethal effect of aluminum (ALC13, Mallinckrodt) in Bufo arenarum embryos by means of simultaneous zinc (ZnSO4) treatment is reported. The aluminum hazard was evaluated in a 7 day renewal toxicity testing study conducted with batches of 10 individuals (by quadruplicate) in six concentrations of aluminum plus the control at 20 C. The pH of the experimental solutions were measured. The LC100 expressed as Al(3 +) mg/L at 24 and up tillmore » 168 hours of treatment were 0.9 (the pH of the solution was 6.2 while in control Holtfreter solution the pH was 6.8). Therefore, aluminum exert a lethal effect on amphibian embryos in concentrations which reduce only slightly the pH of the maintaining solution. The lethal effect of aluminum could be reduced 100% by means of simultaneous treatment with 2 mg Zn(2 +)/L. The results point out the high sensibility of the amphibian embryos to aluminum (LC100/24hs:0.9mg Al(3 +)/L) and therefore, episodic increases in dissolved aluminum, usually concomitant with surface water pH decreases, could produce very harmful effects during embryonic stages of amphibians. The noteworthy beneficial effect of zinc against the lethal effect of aluminum could be of practical value in reducing the harmful effects exerted by aluminum. The conspicuous Al-Zn antagonism points out the need of biological test systems for recording the integrated effects of substances released to the environment.« less

A light-stimulated synaptic transistor with synaptic plasticity and memory functions based on InGaZnO{sub x}–Al{sub 2}O{sub 3} thin film structure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Li, H. K.; Chen, T. P., E-mail: echentp@ntu.edu.sg; Liu, P.

In this work, a synaptic transistor based on the indium gallium zinc oxide (IGZO)–aluminum oxide (Al{sub 2}O{sub 3}) thin film structure, which uses ultraviolet (UV) light pulses as the pre-synaptic stimulus, has been demonstrated. The synaptic transistor exhibits the behavior of synaptic plasticity like the paired-pulse facilitation. In addition, it also shows the brain's memory behaviors including the transition from short-term memory to long-term memory and the Ebbinghaus forgetting curve. The synapse-like behavior and memory behaviors of the transistor are due to the trapping and detrapping processes of the holes, which are generated by the UV pulses, at the IGZO/Al{submore » 2}O{sub 3} interface and/or in the Al{sub 2}O{sub 3} layer.« less

Application of thin dielectric films in low coherence fiber-optic Fabry-Pérot sensing interferometers: comparative study

NASA Astrophysics Data System (ADS)

Hirsch, Marzena; Wierzba, Paweł; Jedrzejewska-Szczerska, Małgorzata

2016-11-01

We examine the application of selected thin dielectric films, deposited by atomic layer deposition (ALD), in a low coherence fiber-optic Fabry-Pérot interferometer designed for sensing applications. Such films can be deposited on the end-face of a single mode optical fiber (SMF-28) in order to modify the reflectivity of the Fabry-Pérot cavity, to provide protection of the fibers from aggressive environments or to create a multi-cavity interferometric sensor. Spectral reflectance of films made from zinc oxide (ZnO), titanium dioxide (TiO2), aluminum oxide (Al2O3) and boron nitride (BN) was calculated for various thickness of the films and compared. The results show that the most promising materials for use in fiber-optic Fabry-Pérot interferometer are TiO2 and ZnO, although Al2O3 is also suitable for this application.

21 CFR 73.1991 - Zinc oxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

... amounts consistent with good manufacturing practice. (d) Labeling. The color additive and any mixtues... ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1991 Zinc oxide. (a) Identity. (1) The color additive zinc...). It is principally composed of Zn. (2) Color additive mixtures for drug use made with zinc oxide may...

Pulsed metallic-plasma generators.

NASA Technical Reports Server (NTRS)

Gilmour, A. S., Jr.; Lockwood, D. L.

1972-01-01

A pulsed metallic-plasma generator is described which utilizes a vacuum arc as the plasma source. The arc is initiated on the surface of a consumable cathode which can be any electrically conductive material. Ignition is accomplished by using a current pulse to vaporize a portion of a conductive film on the surface of an insulator separating the cathode from the ignition electrode. The film is regenerated during the ensuing arc. Over 100 million ignition cycles have been accomplished by using four 0.125-in. diameter zinc cathodes operating in parallel and high-density aluminum-oxide insulators. Among the applications being investigated for the generator are metal deposition, vacuum pumping, electric propulsion, and high-power dc arc interruption.

Effect of AZO deposition on antireflective property of Si subwavelength grating structures

NASA Astrophysics Data System (ADS)

Leem, J. W.; Song, Y. M.; Lee, Y. T.; Yu, J. S.

2011-12-01

We investigate the effect of the aluminum-doped zinc oxide (AZO) deposition on the fabricated Si SWG structure on its antireflection characteristics for solar cell applications. The Si SWGs with the two-dimensional periodic nanostructure are fabricated by using holographic lithography and subsequent ICP etching process in SiCl4 plasma. For the antireflection analysis of AZO thin-film on the Si SWG structure, the optical reflectivity is measured experimentally. The maxima reflectance and its oscillation of the structure are significantly decreased on average than those of AZO thin-film on Si substrate over a wide wavelength range of 300-1100 nm, indicating average reflectance less than 4.5% with the maxima of <10%.

Zinc oxide overdose

MedlinePlus

Zinc oxide is an ingredient in many products. Some of these are certain creams and ointments used ... prevent or treat minor skin burns and irritation. Zinc oxide overdose occurs when someone eats one of ...

ELECTRO-DEPOSITION OF NICKEL ALLOYS FROM THE PYROPHOSPHATE BATH: NICKEL- ZINC AND NICKEL-MOLYBDENUM ALLOYS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Panikkar, S.K.; Char, T.L.R.

1958-02-01

Results of studies on the electrodeposition of nickel-zinc and nickel-- molybdenum alloys in a pyrophosphate bath using platinium electrodes are presented. The fects of varying current density and metal contents of the electrolyte on alloy deposit composition, cathode efficiency, and cathode potential are presented in tabular form. (J.R.D.) l2432 A study was made of the effect of homogenization on the mechanical properties of solution-treated and aged aluminum and the quantitative effects of several variables on hardness. The effect of alloying elements on the increase in hardness of aluminum is shown. (J.E.D.)

Viscous properties of aluminum oxide nanotubes and aluminium oxide nanoparticles - silicone oil suspensions

NASA Astrophysics Data System (ADS)

Thapa, Ram; French, Steven; Delgado, Adrian; Ramos, Carlos; Gutierrez, Jose; Chipara, Mircea; Lozano, Karen

2010-03-01

Electrorheological (ER) fluids consisting of γ-aluminum oxide nanotubes and γ-aluminum oxide nanoparticles dispersed within silicone oil were prepared. The relationship between shear stress and shear rate was measured and theoretically simulated by using an extended Bingham model for both the rheological and electrorheological features of these systems. Shear stress and viscosity showed a sharp increase for the aluminum oxide nanotubes suspensions subjected to applied electric fields whereas aluminum oxide nanoparticles suspensions showed a moderate change. It was found that the transition from liquid to solid state (mediated by the applied electric field) can be described by a power law and that for low applied voltages the relationship is almost linear.

Carbothermic reduction and prereduced charge for producing aluminum-silicon alloys

DOEpatents

Stevenson, David T.; Troup, Robert L.

1985-01-01

Disclosed is a method for the carbothermic reduction of aluminum oxide to form an aluminum alloy including producing silicon carbide by heating a first mix of carbon and silicon oxide in a combustion reactor to an elevated temperature sufficient to produce silicon carbide at an accelerated rate, the heating being provided by an in situ combustion with oxygen gas, and then admixing the silicon carbide with carbon and aluminum oxide to form a second mix and heating the second mix in a second reactor to an elevated metal-forming temperature sufficient to produce aluminum-silicon alloy. The prereduction step includes holding aluminum oxide substantially absent from the combustion reactor. The metal-forming step includes feeding silicon oxide in a preferred ratio with silicon carbide.

Critical Role of Zinc as Either an Antioxidant or a Prooxidant in Cellular Systems

PubMed Central

2018-01-01

Zinc is recognized as an essential trace metal required for human health; its deficiency is strongly associated with neuronal and immune system defects. Although zinc is a redox-inert metal, it functions as an antioxidant through the catalytic action of copper/zinc-superoxide dismutase, stabilization of membrane structure, protection of the protein sulfhydryl groups, and upregulation of the expression of metallothionein, which possesses a metal-binding capacity and also exhibits antioxidant functions. In addition, zinc suppresses anti-inflammatory responses that would otherwise augment oxidative stress. The actions of zinc are not straightforward owing to its numerous roles in biological systems. It has been shown that zinc deficiency and zinc excess cause cellular oxidative stress. To gain insights into the dual action of zinc, as either an antioxidant or a prooxidant, and the conditions under which each role is performed, the oxidative stresses that occur in zinc deficiency and zinc overload in conjunction with the intracellular regulation of free zinc are summarized. Additionally, the regulatory role of zinc in mitochondrial homeostasis and its impact on oxidative stress are briefly addressed. PMID:29743987

Organofunctional Silane Modification of Aluminum-Doped Zinc Oxide Surfaces as a Route to Stabilization

DOE PAGES

Matthews, Rachael; Glasser, Emily; Sprawls, Samuel C.; ...

2017-05-01

Aluminum-doped zinc oxide (AZO) is a low-temperature processed transparent conductive oxide (TCO) made of earth abundant elements; its applications are currently limited by instability to heat, moisture, and acidic conditions. We demonstrate that the application of an organofunctional silane modifier mitigates AZO degradation, and explore the interplay between performance and material composition and morphology. Specifically, we evaluate degradation of bare AZO and APTES (3-aminopropyltriethoxysilane)-modified AZO in response to damp heat (DH, 85 °C, 85 % relative humidity) exposure over 1000 h, then demonstrate how surface modification impacts changes in electrical and optical properties, and chemical composition in one of themore » most thorough studies to date. Hall measurements show that the resistivity of AZO increases due to a decrease in electron mobility, with no commensurate change in carrier concentration. APTES decelerates this electrical degradation, without affecting AZO optical properties. Percent transmission and yellowness index of an ensemble of bare and modified AZO are stable upon DH exposure, but haze increases slightly for a discrete sample of modified AZO. Atomic force microscopy (AFM) and optical profilometer (OP) measurements do not show evidence of pitting or delamination after 1000 h DH exposure, but indicate a slight increase in surface roughness on both the nanometer and micron length scales. X-ray photoelectron spectroscopy data (XPS) reveal that the surface composition of bare and silanized AZO is stable over this time frame; oxygen vacancies, as measured by XPS, are also stable with DH exposure, which, together with transmission and Hall measurements, indicate stable carrier concentrations. However, after 1500 h of DH exposure, only bare AZO shows signs of catastrophic destruction. Comparison of the data presented herein to previous reports indicates that the initial AZO composition and microstructure dictate the degradation profile. Furthermore, this work demonstrates that surface modification slows the bulk degradation of AZO, and provides insight into how the material can be more widely used as a transparent electrode in the next generation of optoelectronic devices.« less

Organofunctional Silane Modification of Aluminum-Doped Zinc Oxide Surfaces as a Route to Stabilization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Matthews, Rachael; Glasser, Emily; Sprawls, Samuel C.

Aluminum-doped zinc oxide (AZO) is a low-temperature processed transparent conductive oxide (TCO) made of earth abundant elements; its applications are currently limited by instability to heat, moisture, and acidic conditions. We demonstrate that the application of an organofunctional silane modifier mitigates AZO degradation, and explore the interplay between performance and material composition and morphology. Specifically, we evaluate degradation of bare AZO and APTES (3-aminopropyltriethoxysilane)-modified AZO in response to damp heat (DH, 85 °C, 85 % relative humidity) exposure over 1000 h, then demonstrate how surface modification impacts changes in electrical and optical properties, and chemical composition in one of themore » most thorough studies to date. Hall measurements show that the resistivity of AZO increases due to a decrease in electron mobility, with no commensurate change in carrier concentration. APTES decelerates this electrical degradation, without affecting AZO optical properties. Percent transmission and yellowness index of an ensemble of bare and modified AZO are stable upon DH exposure, but haze increases slightly for a discrete sample of modified AZO. Atomic force microscopy (AFM) and optical profilometer (OP) measurements do not show evidence of pitting or delamination after 1000 h DH exposure, but indicate a slight increase in surface roughness on both the nanometer and micron length scales. X-ray photoelectron spectroscopy data (XPS) reveal that the surface composition of bare and silanized AZO is stable over this time frame; oxygen vacancies, as measured by XPS, are also stable with DH exposure, which, together with transmission and Hall measurements, indicate stable carrier concentrations. However, after 1500 h of DH exposure, only bare AZO shows signs of catastrophic destruction. Comparison of the data presented herein to previous reports indicates that the initial AZO composition and microstructure dictate the degradation profile. Furthermore, this work demonstrates that surface modification slows the bulk degradation of AZO, and provides insight into how the material can be more widely used as a transparent electrode in the next generation of optoelectronic devices.« less

Human skin penetration and local effects of topical nano zinc oxide after occlusion and barrier impairment.

PubMed

Leite-Silva, V R; Sanchez, W Y; Studier, H; Liu, D C; Mohammed, Y H; Holmes, A M; Ryan, E M; Haridass, I N; Chandrasekaran, N C; Becker, W; Grice, J E; Benson, H A E; Roberts, M S

2016-07-01

Public health concerns continue to exist over the safety of zinc oxide nanoparticles that are commonly used in sunscreen formulations. In this work, we assessed the effects of two conditions which may be encountered in everyday sunscreen use, occlusion and a compromised skin barrier, on the penetration and local toxicity of two topically applied zinc oxide nanoparticle products. Caprylic/capric triglyceride (CCT) suspensions of commercially used zinc oxide nanoparticles, either uncoated or with a silane coating, were applied to intact and barrier impaired skin of volunteers, without and with occlusion for a period of six hours. The exposure time was chosen to simulate normal in-use conditions. Multiphoton tomography with fluorescence lifetime imaging was used to noninvasively assess zinc oxide penetration and cellular metabolic changes that could be indicative of toxicity. We found that zinc oxide nanoparticles did not penetrate into the viable epidermis of intact or barrier impaired skin of volunteers, without or with occlusion. We also observed no apparent toxicity in the viable epidermis below the application sites. These findings were validated by ex vivo human skin studies in which zinc penetration was assessed by multiphoton tomography with fluorescence lifetime imaging as well as Zinpyr-1 staining and toxicity was assessed by MTS assays in zinc oxide treated skin cryosections. In conclusion, applications of zinc oxide nanoparticles under occlusive in-use conditions to volunteers are not associated with any measurable zinc oxide penetration into, or local toxicity in the viable epidermis below the application site. Copyright © 2016 Elsevier B.V. All rights reserved.

Symposium P: Three-Dimensional Architectures for Energy Generation and Storage

DTIC Science & Technology

2010-09-02

anodic oxidation of aluminum to produce anodic aluminum oxide ( AAO ). The nanopores have diameters 15-100nm and depths 1-30um... aluminum oxide ( AAO ) template which can be successfully applied for fabrication of vertically aligned SiNWs. Then, we have investigated the electrical...performed in quiescent and rotating disc electrode (RDE) experiments. PSJfl Lateral Growth of Deep Nanopores in Anodic Aluminum Oxide as a Platform

Temperature-Driven Structural and Morphological Evolution of Zinc Oxide Nano-Coalesced Microstructures and Its Defect-Related Photoluminescence Properties

PubMed Central

Lim, Karkeng; Abdul Hamid, Muhammad Azmi; Shamsudin, Roslinda; Al-Hardan, N.H.; Mansor, Ishak; Chiu, Weesiong

2016-01-01

In this paper, we address the synthesis of nano-coalesced microstructured zinc oxide thin films via a simple thermal evaporation process. The role of synthesis temperature on the structural, morphological, and optical properties of the prepared zinc oxide samples was deeply investigated. The obtained photoluminescence and X-ray photoelectron spectroscopy outcomes will be used to discuss the surface structure defects of the prepared samples. The results indicated that the prepared samples are polycrystalline in nature, and the sample prepared at 700 °C revealed a tremendously c-axis oriented zinc oxide. The temperature-driven morphological evolution of the zinc oxide nano-coalesced microstructures was perceived, resulting in transformation of quasi-mountain chain-like to pyramidal textured zinc oxide with increasing the synthesis temperature. The results also impart that the sample prepared at 500 °C shows a higher percentage of the zinc interstitial and oxygen vacancies. Furthermore, the intensity of the photoluminescence emission in the ultraviolet region was enhanced as the heating temperature increased from 500 °C to 700 °C. Lastly, the growth mechanism of the zinc oxide nano-coalesced microstructures is discussed according to the reaction conditions. PMID:28773425

Synthesis, characterization and application of two-dimensional layered metal hydroxides for environmental remediation purposes

NASA Astrophysics Data System (ADS)

Machingauta, Cleopas

Two-dimensional layered nano composites, which include layered double hydroxides (LDHs), hydroxy double salts (HDSs) and layered hydroxide salts (LHSs) are able to intercalate different molecular species within their gallery space. These materials have a tunable structural composition which has made them applicable as fire retardants, adsorbents, catalysts, catalyst support materials, and ion exchangers. Thermal treatment of these materials results in destruction of the layers and formation of mixed metal oxides (MMOs) and spinels. MMOs have the ability to adsorb anions from solution and may also regenerate layered structures through a phenomenon known as memory effect. Zinc-nickel hydroxy nitrate was used for the uptake of a series of halogenated acetates (HAs). HAs are pollutants introduced into water systems as by-products of water chlorination and pesticide degradation; their sequestration from water is thus crucial. Optimization of layered materials for controlled uptake requires an understanding of their ion-exchange kinetics and thermodynamics. Exchange kinetics of these anions was monitored using ex-situ PXRD, UV-vis, HPLC and FTIR. It was revealed that exchange rates and uptake efficiencies are related to electronic spatial extents and the charge on carboxyl-oxygen atoms. In addition, acetate and nitrate-based HDSs were used to explore how altering the hydroxide layer affects uptake of acetate/nitrate ions. Changing the metal identities affects the interaction of the anions with the layers. From FTIR, we observed that nitrates coordinate in a D3h and Cs/C 2v symmetry; the nitrates in D3h symmetry were easily exchangeable. Interlayer hydrogen bonding was also revealed to be dependent on metal identity. Substituting divalent cations with trivalent cations produces materials with a higher charge density than HDSs and LHSs. A comparison of the uptake efficiency of zinc-aluminum, zinc-gallium and zinc-nickel hydroxy nitrates was performed using trichloroacetic acid as target anion. Uptake efficiency was better for LDHs than HDS, and between the LDHs, zinc-aluminum hydroxy nitrate was the best material for the uptake of tClAc. Calcined LDHs were applied for the uptake of methyl-orange, model azo-dye. The ability to regenerate the layered structures was helpful for improving adsorption efficiency. It has been reveal that calcined LDHs are also better adsorbents than calcined HDSs.

Effect of morphology and solvent on two-photon absorption of nano zinc oxide

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kavitha, M.K.; Haripadmam, P.C.; Gopinath, Pramod

Highlights: ► ZnO nanospheres and triangular structures synthesis by novel precipitation technique. ► The effect of precursor concentration on the size and shape of nano ZnO. ► Open aperture Z-scan measurements of the ZnO nanoparticle dispersions. ► Nanospheres exhibit higher two photon absorption coefficient than triangular nanostructures. ► Nanospheres dispersed in water exhibit higher two photon absorption coefficient than its dispersion in 2-propanol. - Abstract: In this paper, we report the effect of morphology and solvent on the two-photon absorption of nano zinc oxide. Zinc oxide nanoparticles in two different morphologies like nanospheres and triangular nanostructures are synthesized by novelmore » precipitation technique and their two-photon absorption coefficient is measured using open aperture Z-scan technique. Experimental results show that the zinc oxide nanospheres exhibit higher two-photon absorption coefficient than the zinc oxide triangular nanostructures. The zinc oxide nanospheres dispersed in water exhibit higher two-photon absorption coefficient than that of its dispersion in 2-propanol. The zinc oxide nanospheres dispersed in water shows a decrease in two-photon absorption coefficient with an increase in on-axis irradiance. The result confirms the dependence of shape and solvent on the two-photon absorption of nano zinc oxide.« less

Bioavailability of zinc oxide added to corn tortilla is similar to that of zinc sulfate and is not affected by simultaneous addition of iron

PubMed Central

Rosado, Jorge L.; Díaz, Margarita; Muñoz, Elsa; Westcott, Jamie L.; González, Karla E.; Krebs, Nancy F.; Caamaño, María C.; Hambidge, Michael

2013-01-01

Background Corn tortilla is the staple food of Mexico and its fortification with zinc, iron, and other micronutrients is intended to reduce micronutrient deficiencies. However, no studies have been performed to determine the relative amount of zinc absorbed from the fortified product and whether zinc absorption is affected by the simultaneous addition of iron. Objective To compare zinc absorption from corn tortilla fortified with zinc oxide versus zinc sulfate and to determine the effect of simultaneous addition of two doses of iron on zinc bioavailability. Methods A randomized, double-blind, crossover design was carried out in two phases. In the first phase, 10 adult women received corn tortillas with either 20 mg/kg of zinc oxide added, 20 mg/kg of zinc sulfate added, or no zinc added. In the second phase, 10 adult women received corn tortilla with 20 mg/kg of zinc oxide added and either with no iron added or with iron added at one of two different levels. Zinc absorption was measured by the stable isotope method. Results The mean (± SEM) fractional zinc absorption from unfortified tortilla, tortilla fortified with zinc oxide, and tortilla fortified with zinc sulfate did not differ among treatments: 0.35 ± 0.07, 0.36 ± 0.05, and 0.37 ± 0.07, respectively. The three treatment groups with 0, 30, and 60 mg/kg of added iron had similar fractional zinc absorption (0.32 ± 0.04, 0.33 ± 0.02, and 0.32 ± 0.05, respectively) and similar amounts of zinc absorbed (4.8 ± 0.7, 4.5 ± 0.3, and 4.8 ± 0.7 mg/day, respectively). Conclusions Since zinc oxide is more stable and less expensive and was absorbed equally as well as zinc sulfate, we suggest its use for corn tortilla fortification. Simultaneous addition of zinc and iron to corn tortilla does not modify zinc bioavailability at iron doses of 30 and 60 mg/kg of corn flour. PMID:23424892

40 CFR 421.36 - Pretreatment standards for new sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... dried Lead .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000 (b) Subpart C—Scrap Screening and Milling... per million pounds) of aluminum scrap screened and milled Lead .000 .000 Zinc .000 .000 Ammonia (as N... .000 Ammonia (as N) .000 .000 (d) Subpart C—Demagging Wet Air Pollution Control. PSNS Pollutant or...

40 CFR 421.36 - Pretreatment standards for new sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... dried Lead .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000 (b) Subpart C—Scrap Screening and Milling... per million pounds) of aluminum scrap screened and milled Lead .000 .000 Zinc .000 .000 Ammonia (as N... .000 Ammonia (as N) .000 .000 (d) Subpart C—Demagging Wet Air Pollution Control. PSNS Pollutant or...

40 CFR 421.36 - Pretreatment standards for new sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... dried Lead .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000 (b) Subpart C—Scrap Screening and Milling... per million pounds) of aluminum scrap screened and milled Lead .000 .000 Zinc .000 .000 Ammonia (as N... .000 Ammonia (as N) .000 .000 (d) Subpart C—Demagging Wet Air Pollution Control. PSNS Pollutant or...

40 CFR 421.36 - Pretreatment standards for new sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... dried Lead .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000 (b) Subpart C—Scrap Screening and Milling... per million pounds) of aluminum scrap screened and milled Lead .000 .000 Zinc .000 .000 Ammonia (as N... .000 Ammonia (as N) .000 .000 (d) Subpart C—Demagging Wet Air Pollution Control. PSNS Pollutant or...

40 CFR 421.36 - Pretreatment standards for new sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... dried Lead .000 .000 Zinc .000 .000 Ammonia (as N) .000 .000 (b) Subpart C—Scrap Screening and Milling... per million pounds) of aluminum scrap screened and milled Lead .000 .000 Zinc .000 .000 Ammonia (as N... .000 Ammonia (as N) .000 .000 (d) Subpart C—Demagging Wet Air Pollution Control. PSNS Pollutant or...

SIMS depth profiling of rubber-tyre cord bonding layers prepared using 64Zn depleted ZnO

NASA Astrophysics Data System (ADS)

Fulton, W. S.; Sykes, D. E.; Smith, G. C.

2006-07-01

Zinc oxide and copper/zinc sulphide layers are formed during vulcanisation and moulding of rubber to brass-coated steel tyre reinforcing cords. Previous studies have described how zinc diffuses through the rubber-brass interface to form zinc sulphide, and combines with oxygen to create zinc oxide during dezincification. The zinc is usually assumed to originate in the brass of the tyre cord, however, zinc oxide is also present in the rubber formulation. We reveal how zinc from these sources is distributed within the interfacial bonding layers, before and after heat and humidity ageing. Zinc oxide produced using 64Zn-isotope depleted zinc was mixed in the rubber formulation in place of the natural ZnO and the zinc isotope ratios within the interfacial layers were followed by secondary ion mass spectroscopy (SIMS) depth profiling. Variations in the relative ratios of the zinc isotopes during depth profiling were measured for unaged, heat-aged and humidity-aged wire samples and in each case a relatively large proportion of the zinc incorporated into the interfacial layer as zinc sulphide was shown to have originated from ZnO in the rubber compound.

Carbothermic reduction and prereduced charge for producing aluminum-silicon alloys

DOEpatents

Stevenson, D.T.; Troup, R.L.

1985-01-01

Disclosed is a method for the carbothermic reduction of aluminum oxide to form an aluminum alloy including producing silicon carbide by heating a first mix of carbon and silicon oxide in a combustion reactor to an elevated temperature sufficient to produce silicon carbide at an accelerated rate, the heating being provided by an in situ combustion with oxygen gas, and then admixing the silicon carbide with carbon and aluminum oxide to form a second mix and heating the second mix in a second reactor to an elevated metal-forming temperature sufficient to produce aluminum-silicon alloy. The prereduction step includes holding aluminum oxide substantially absent from the combustion reactor. The metal-forming step includes feeding silicon oxide in a preferred ratio with silicon carbide. 1 fig.

Mechanical properties of bioplastics cassava starch film with Zinc Oxide nanofiller as reinforcement

NASA Astrophysics Data System (ADS)

Harunsyah; Yunus, M.; Fauzan, Reza

2017-06-01

This study focuses on investigating the influence of zinc oxide nanofiller on the mechanical properties of bioplastic cassava starch films. Bioplastic cassava starch film-based zinc oxide reinforced composite biopolymeric films were prepared by casting technique. The content of zinc oxide in the bioplastic films was varied from 0.2%, 0.4%, 0.6%, 0.8% and 1.0% (w/w) by weight of starch. Surface morphologies of the composites bioplastic films were examined by scanning electron microscope (SEM).The result showed that the Tensile strength (TS) was improved significantly with the additional of zinc oxide but the elongation at break (EB %) of the composites was decreased. The maximum tensile strength obtained was 22.30 kgf / mm on the additional of zinc oxide by 0.6% and plastilizer by 25%. Based on data of FTIR, the produced film plastic did not change the group function and it can be concluded that theinteraction in film plastic produced was only a physical interaction. Biodegradable plastic film based on cassava starch-zinc oxide and plasticizer glycerol showed that interesting mechanical properties being transparent, clear, homogeneous, flexible, and easily handled.

Improved synthesis of fine zinc borate particles using seed crystals

NASA Astrophysics Data System (ADS)

Gürhan, Deniz; Çakal, Gaye Ö.; Eroğlu, İnci; Özkar, Saim

2009-03-01

Zinc borate is a flame retardant additive used in polymers, wood applications and textile products. There are different types of zinc borate having different chemical compositions and structures. In this study, the production of zinc borate having the molecular formula of 2ZnO·3B 2O 3·3.5H 2O was reexamined by studying the effects of reaction parameters on the properties of product as well as the reaction kinetics. Production of zinc borate from the reaction of boric acid and zinc oxide in the presence of seed crystals was performed in a continuously stirred, temperature-controlled batch reactor having a volume of 1.5 L. Samples taken in regular time intervals during the experiments were analyzed for the concentration of zinc oxide and boron oxide in the solid as well as for the conversion of zinc oxide to zinc borate versus time. The zinc borate production reaction was fit to the logistic model. The reaction rate, reaction completion time, composition and particle size distribution of zinc borate product were determined by varying the following parameters: the boric acid to zinc oxide ratio (H 3BO 3:ZnO=3:1, 3.5:1, 5:1 and 7:1), the particle size of zinc oxide (10 and 25 μm), stirring rate (275, 400, 800 and 1600 rpm), temperature (75, 85 and 95 °C) and the size of seed crystals (10 and 2 μm). The products were also analyzed for particle size distribution. The experimental results showed that the reaction rate increases with the increase in H 3BO 3:ZnO ratio, particle size of zinc oxide, stirring rate and temperature. Concomitantly, the reaction completion time is decreased by increasing the H 3BO 3:ZnO ratio, stirring rate and temperature. The average particle sizes of the zinc borate products are in the range 4.3-16.6 μm (wet dispersion analysis).

MTBE OXIDATION BY BIFUNCTIONAL ALUMINUM

EPA Science Inventory

Bifunctional aluminum, prepared by sulfating zero-valent aluminum with sulfuric acid, has a dual functionality of simultaneously decomposing both reductively- and oxidatively-degradable contaminants. In this work, the use of bifunctional aluminum for the degradation of methyl te...

Atomic-Scale Insights into the Oxidation of Aluminum.

PubMed

Nguyen, Lan; Hashimoto, Teruo; Zakharov, Dmitri N; Stach, Eric A; Rooney, Aidan P; Berkels, Benjamin; Thompson, George E; Haigh, Sarah J; Burnett, Tim L

2018-01-24

The surface oxidation of aluminum is still poorly understood despite its vital role as an insulator in electronics, in aluminum-air batteries, and in protecting the metal against corrosion. Here we use atomic resolution imaging in an environmental transmission electron microscope (TEM) to investigate the mechanism of aluminum oxide formation. Harnessing electron beam sputtering we prepare a pristine, oxide-free metal surface in the TEM. This allows us to study, as a function of crystallographic orientation and oxygen gas pressure, the full oxide growth regime from the first oxide nucleation to a complete saturated, few-nanometers-thick surface film.

A review of zinc oxide mineral beneficiation using flotation method.

PubMed

Ejtemaei, Majid; Gharabaghi, Mahdi; Irannajad, Mehdi

2014-04-01

In recent years, extraction of zinc from low-grade mining tailings of oxidized zinc has been a matter of discussion. This is a material which can be processed by flotation and acid-leaching methods. Owing to the similarities in the physicochemical and surface chemistry of the constituent minerals, separation of zinc oxide minerals from their gangues by flotation is an extremely complex process. It appears that selective leaching is a promising method for the beneficiation of this type of ore. However, with the high consumption of leaching acid, the treatment of low-grade oxidized zinc ores by hydrometallurgical methods is expensive and complex. Hence, it is best to pre-concentrate low-grade oxidized zinc by flotation and then to employ hydrometallurgical methods. This paper presents a critical review on the zinc oxide mineral flotation technique. In this paper, the various flotation methods of zinc oxide minerals which have been proposed in the literature have been detailed with the aim of identifying the important factors involved in the flotation process. The various aspects of recovery of zinc from these minerals are also dealt with here. The literature indicates that the collector type, sulfidizing agent, pH regulator, depressants and dispersants types, temperature, solid pulp concentration, and desliming are important parameters in the process. The range and optimum values of these parameters, as also the adsorption mechanism, together with the resultant flotation of the zinc oxide minerals reported in the literature are summarized and highlighted in the paper. This review presents a comprehensive scientific guide to the effectiveness of flotation strategy. Copyright © 2013 Elsevier B.V. All rights reserved.

Attrition resistant, zinc titanate-containing, reduced sulfur sorbents and methods of use thereof

DOEpatents

Vierheilig, Albert A.; Gupta, Raghubir P.; Turk, Brian S.

2006-06-27

Reduced sulfur gas species (e.g., H.sub.2S, COS and CS.sub.2) are removed from a gas stream by compositions wherein a zinc titanate ingredient is associated with a metal oxide-aluminate phase material in the same particle species. Nonlimiting examples of metal oxides comprising the compositions include magnesium oxide, zinc oxide, calcium oxide, nickel oxide, etc.

Sulfur-Doped Zinc Oxide (ZnO) Nanostars: Synthesis and Simulation of Growth Mechanism

DTIC Science & Technology

2011-10-01

Zinc Oxide ( ZnO ) Nanostars: Synthesis and Simulation of Growth Mechanism Jinhyun Cho1, Qiubao Lin2,3, Sungwoo...characterization, and ab initio simulations of star-shaped hexagonal zinc oxide ( ZnO ) nanowires. The ZnO nanostructures were synthesized by a low...Introduction Zinc oxide ( ZnO ) is a wide bandgap (3.37 eV), Ⅱ–Ⅵ semiconductor of great interest for optoelectronic applications [1–3]. Its

High resolution masks for ion milling pores through substrates of biological interest

NASA Technical Reports Server (NTRS)

Donovan, S. S.

1978-01-01

The feasibility was investigated of electrochemically oxidizing vapor deposited aluminum coatings to produce porous aluminum oxide coatings with submicron pore diameters and with straight channels normal to the substrate surface. Porous aluminum oxide coatings were produced from vapor deposited aluminum coatings on thin stainless steel (304), copper, Teflon (FEP) and Kapton substrates and also on pure aluminum substrates. Scanning electron microscope examination indicated that porous oxide coatings can be produced with straight channels, appropriate pore diameters and none or minimal intervening residual aluminum. The oxide coatings on the copper and Kapton substrates had the straightest channels and in general were superior to those fabricated on the other substrate materials. For oxide coatings fabricated at 600 V and 300 V, pore diameters were 0.4-0.6, and 0.3 micron with center-to-center spacing of 0.7-0.8, and 0.4 micron, respectively. Estimated direct labor and materials costs to prepare an oxide mask is anticipated to be about $4-$6 per square foot.

Liquid-Like, Self-Healing Aluminum Oxide during Deformation at Room Temperature.

PubMed

Yang, Yang; Kushima, Akihiro; Han, Weizhong; Xin, Huolin; Li, Ju

2018-04-11

Effective protection from environmental degradation relies on the integrity of oxide as diffusion barriers. Ideally, the passivation layer can repair its own breaches quickly under deformation. While studies suggest that the native aluminum oxide may manifest such properties, it has yet to be experimentally proven because direct observations of the air-environmental deformation of aluminum oxide and its initial formation at room temperature are challenging. Here, we report in situ experiments to stretch pure aluminum nanotips under O 2 gas environments in a transmission electron microscope (TEM). We discovered that aluminum oxide indeed deforms like liquid and can match the deformation of Al without any cracks/spallation at moderate strain rate. At higher strain rate, we exposed fresh metal surface, and visualized the self-healing process of aluminum oxide at atomic resolution. Unlike traditional thin-film growth or nanoglass consolidation processes, we observe seamless coalescence of new oxide islands without forming any glass-glass interface or surface grooves, indicating greatly accelerated glass kinetics at the surface compared to the bulk.

Ni/metal hydride secondary element

DOEpatents

Bauerlein, Peter

2005-04-19

A Ni/metal hydride secondary element having a positive nickel hydroxide electrode, a negative electrode having a hydrogen storage alloy, and an alkaline electrolyte, the positive electrode, provided with a three-dimensional metallic conductive structure, also contains an aluminum compound which is soluble in the electrolyte, in addition to nickel hydroxide and cobalt oxide. The aluminum compound is aluminum hydroxide and/or aluminum oxide, and the mass of the aluminum compound which is present in the positive bulk material mixture is 0.1 to 2% by weight relative to the mass of the nickel hydroxide which is present. In combination with aluminum hydroxide or aluminum oxide, the positive electrode further contains lanthanoid oxidic compounds Y.sub.2 O.sub.3, La.sub.2 O.sub.3 and Ca(OH).sub.2, as well as mixtures of these compounds.

21 CFR 582.5991 - Zinc oxide.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Zinc oxide. 582.5991 Section 582.5991 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary Supplements 1 § 582.5991 Zinc oxide. (a) Product. Zinc...

21 CFR 582.5991 - Zinc oxide.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Zinc oxide. 582.5991 Section 582.5991 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients and/or Dietary Supplements 1 § 582.5991 Zinc oxide. (a) Product. Zinc...

Effect of temperature on the adsorption of sulfanilamide onto aluminum oxide and its molecular dynamics simulations

NASA Astrophysics Data System (ADS)

Ji, Ying-xue; Wang, Feng-he; Duan, Lun-chao; Zhang, Fan; Gong, Xue-dong

2013-11-01

The effect of temperature on the adsorption of sulfanilamide (SA) onto aluminum oxide was researched through batch adsorption experiments, and was then simulated using the molecular dynamics (MD) method. The results show that SA can be adsorbed effectively by the adsorbent of aluminum oxide due to their interactions between SA molecule and the surface of aluminum oxide crystal, and temperature is a key factor which influences the adsorption efficiency obviously. The removal ratio of SA at 298 K is the highest among the selected temperatures (293 K, 298 K, 303 K). MD simulations revealed the interactions between SA molecules and (0 1 2) surface of aluminum oxide crystal at molecular level. The SA molecule has clung to the (0 1 2) face of aluminum oxide crystal, and its structure is deformed during its combining process with the surface. Both binding energies (Eb) and deformation energies (ΔEdeform) in the SA-aluminum oxide system follow the same order as: SA-Al2O3 (298 K) > SA-Al2O3 (293 K) > SA-Al2O3 (303 K). Their deformation energies are far less than their non-bonding energies. Analysis of radial distribution functions (RDFs) indicates that SA can be adsorbed effectively by aluminum oxide crystal mainly through non-bond interactions. The simulation results agree well with the experimental results, which verify the rationality and reliability of the MD simulation. The further MD simulations provide theoretically optimal temperature (301 K) for the adsorption of SA onto aluminum oxide. The molecular dynamics simulation will be useful for better understanding the adsorption mechanism of antibiotics onto metal oxides, which will also be helpful for optimizing experimental conditions to improve the adsorptive removal efficiency of antibiotics.

Analysis of Zinc Oxide Thin Films Synthesized by Sol-Gel via Spin Coating

NASA Astrophysics Data System (ADS)

Wolgamott, Jon Carl

Transparent conductive oxides are gaining an increasingly important role in optoelectronic devices such as solar cells. Doped zinc oxide is a candidate as a low cost and nontoxic alternative to tin doped indium oxide. Lab results have shown that both n-type and p-type zinc oxide can be created on a small scale. This can allow zinc oxide to be used as either an electrode as well as a buffer layer to increase efficiency and protect the active layer in solar cells. Sol-gel synthesis is emerging as a low temperature, low cost, and resource efficient alternative to producing transparent conducting oxides such as zinc oxide. For sol-gel derived zinc oxide thin films to reach their potential, research in this topic must continue to optimize the known processing parameters and expand to new parameters to tighten control and create novel processing techniques that improve performance. The processing parameters of drying and annealing temperatures as well as cooling rate were analyzed to see their effect on the structure of the prepared zinc oxide thin films. There were also preliminary tests done to modify the sol-gel process to include silver as a dopant to produce a p-type thin film. The results from this work show that the pre- and post- heating temperatures as well as the cooling rate all play their own unique role in the crystallization of the film. Results from silver doping show that more work needs to be done to create a sol-gel derived p-type zinc oxide thin film.

Zinc and redox signaling: perturbations associated with cardiovascular disease and diabetes mellitus.

PubMed

Foster, Meika; Samman, Samir

2010-11-15

Cellular signal transduction pathways are influenced by the zinc and redox status of the cell. Numerous chronic diseases, including cardiovascular disease (CVD) and diabetes mellitus (DM), have been associated with impaired zinc utilization and increased oxidative stress. In humans, mutations in the MT-1A and ZnT8 genes, both of which are involved in the maintenance of zinc homeostasis, have been linked with DM development. Changes in levels of intracellular free zinc may exacerbate oxidative stress in CVD and DM by impacting glutathione homeostasis, nitric oxide signaling, and nuclear factor-kappa B-dependent cellular processes. Zinc ions have been shown to influence insulin and leptin signaling via the phosphoinositide 3′-kinase/Akt pathway, potentially linking an imbalance of zinc at the cellular level to insulin resistance and dyslipidemia. The oxidative modification of cysteine residues in zinc coordination sites in proteins has been implicated in cellular signaling and regulatory pathways. Despite the many interactions between zinc and cellular stress responses, studies investigating the potential therapeutic benefit of zinc supplementation in the prevention and treatment of oxidative stress-related chronic disease in humans are few and inconsistent. Further well-designed randomized controlled trials are needed to determine the effects of zinc supplementation in populations at various stages of CVD and DM progression.

In vitro shear bond strength of cementing agents to fixed prosthodontic restorative materials.

PubMed

Piwowarczyk, Andree; Lauer, Hans-Christoph; Sorensen, John A

2004-09-01

Durable bonding to fixed prosthodontic restorations is desirable; however, little information is available on the strength of the bond between different cements and fixed prosthodontic restorative materials. This study determined the shear-bond strength of cementing agents to high-gold-content alloy castings and different dental ceramics: high-strength aluminum oxide (Procera AllCeram), leucite-reinforced (IPS Empress), and lithium disilicate glass-ceramic (IPS Empress 2). Prepolymerized resin composite cylinders (5.5 mm internal diameter, n=20) were bonded to the pretreated surfaces of prosthodontic materials. High-gold-content alloy and high-strength aluminum oxide surfaces were airborne-particle-abraded, and pressable ceramics were hydrofluoric acid-etched and silanized prior to cementing. The cementing agents tested were a zinc-phosphate cement (Fleck's zinc cement), glass ionomer cements (Fuji I, Ketac-Cem), resin-modified glass ionomer cements (Fuji Plus, Fuji Cem, RelyX Luting), resin cements (RelyX ARC, Panavia F, Variolink II, Compolute), and a self-adhesive universal resin cement (RelyX Unicem). Half the specimens (n=10) were tested after 30 minutes; the other half (n=10) were stored in distilled water at 37 degrees C for 14 days and then thermal cycled 1000 times between 5 degrees C and 55 degrees C prior to testing. Shear-bond strength tests were performed using a universal testing machine at a constant crosshead speed of 0.5 mm/min. Statistical analysis was performed by multifactorial analysis of variance taking interactions between effects into account. For multiple paired comparisons, the Tukey method was used (alpha=.05). In a 3-way ANOVA model, the main factors substrate, cement, time, and all corresponding interactions were statistically significant (all P <.0001). In subsequent separate 1-way or 2-way ANOVA models for each substrate type, significant differences between cement types and polymerizing modes were found (all P <.001). None of the cement types provided the highest bonding values with all substrate types. After 14 days of water storage followed by thermal cycling, only the self-adhesive universal resin cement (RelyX Unicem) and 2 of the resin cements (Panavia F and Compolute) exhibited strong bond strengths to specific prosthodontic materials. In contrast, zinc-phosphate, glass ionomer, and resin-modified glass ionomer cements showed the lowest values of all tested cementing agents after 14 days of water storage followed by thermal cycling.

Method And Reactor For Production Of Aluminum By Carbothermic Reduction Of Alumina

DOEpatents

Aune, Jan Arthur; Johansen, Kai

2004-10-19

A hollow partition wall is employed to feed carbon material to an underflow of a carbothermic reduction furnace used to make aluminum. The partition wall divides a low temperature reaction zone where aluminum oxide is reacted with carbon to form aluminum carbide and a high temperature reaction zone where the aluminum carbide and remaining aluminum oxide are reacted to form aluminum and carbon monoxide.

40 CFR 63.11167 - What definitions apply to this subpart?

Code of Federal Regulations, 2011 CFR

2011-07-01

... melt cadmium or produce cadmium oxide from the cadmium recovered in the zinc production process... engaged in the production, or any intermediate process in the production, of zinc or zinc oxide from zinc... Sources-Zinc, Cadmium, and Beryllium Other Requirements and Information § 63.11167 What definitions apply...

Aluminum powder metallurgy processing

NASA Astrophysics Data System (ADS)

Flumerfelt, Joel Fredrick

In recent years, the aluminum powder industry has expanded into non-aerospace applications. However, the alumina and aluminum hydroxide in the surface oxide film on aluminum powder require high cost powder processing routes. A driving force for this research is to broaden the knowledge base about aluminum powder metallurgy to provide ideas for fabricating low cost aluminum powder components. 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). The commercial atomization methods are bench marks of current aluminum powder technology. The GARS process is a laboratory scale inert gas atomization facility. A benefit of using pure aluminum powders is an unambiguous interpretation of the results without considering the effects of alloy elements. 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 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.

Modeling the ignition of a copper oxide aluminum thermite

NASA Astrophysics Data System (ADS)

Lee, Kibaek; Stewart, D. Scott; Clemenson, Michael; Glumac, Nick; Murzyn, Christopher

2017-01-01

An experimental "striker confinement" shock compression experiment was developed in the Glumac-group at the University of Illinois to study ignition and reaction in composite reactive materials. These include thermitic and intermetallic reactive powders. Sample of materials such as a thermite mixture of copper oxide and aluminum powders are initially compressed to about 80 percent full density. Two RP-80 detonators simultaneously push steel bars into the reactive material and the resulting compression causes shock compaction of the material and rapid heating. At that point one observes significant reaction and propagation of fronts. But the fronts are peculiar in that they are comprised of reactive events that can be traced to the reaction of the initially separated reactants of copper oxide and aluminum that react at their mutual interfaces, that nominally make copper liquid and aluminum oxide products. We discuss our model of the ignition of the copper oxide aluminum thermite in the context of the striker experiment and how a Gibbs formulation model [1], that includes multi-components for liquid and solid phases of aluminum, copper oxide, copper and aluminum oxide, can predict the events observed at the particle scale in the experiments.

Method of coating an iron-based article

DOE Office of Scientific and Technical Information (OSTI.GOV)

Magdefrau, Neal; Beals, James T.; Sun, Ellen Y.

A method of coating an iron-based article includes a first heating step of heating a substrate that includes an iron-based material in the presence of an aluminum source material and halide diffusion activator. The heating is conducted in a substantially non-oxidizing environment, to cause the formation of an aluminum-rich layer in the iron-based material. In a second heating step, the substrate that has the aluminum-rich layer is heated in an oxidizing environment to oxidize the aluminum in the aluminum-rich layer.

40 CFR 467.55 - Pretreatment standards for existing sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... any 1 day Maximum for monthly average mg/off-kg (lb/million off-lbs) of aluminum drawn with neat oils Chromium 0.022 0.009 Cyanide 0.015 0.006 Zinc 0.073 0.031 TTO 0.035 Oil and grease (alternate monitoring...) EFFLUENT GUIDELINES AND STANDARDS ALUMINUM FORMING POINT SOURCE CATEGORY Drawing With Neat Oils Subcategory...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aleman, S.E.

The task was to compute the maximum aluminum-oxide and oxide-coolant temperatures of assemblies cladded in 99+ percent aluminum. The assemblies considered were the Mark VB, VE, V5, 15 and 25. These assemblies consist of nested slug columns with individual uranium slugs cladded in aluminum cans. The CREDIT code was modified to calculate the oxide film thickness and the aluminum-oxide temperature at each axial increment. This information in this report will be used to evaluate the potential for cladding corrosion of the Mark 25 assembly.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aleman, S.E.

The task was to compute the maximum aluminum-oxide and oxide-coolant temperatures of assemblies cladded in 99 plus percent aluminum. The assemblies considered were the Mark VB, VE, V5, 15 and 25. These assemblies consist of nested slug columns with individual uranium slugs cladded in aluminum cans. The CREDIT code was modified to calculate the oxide film thickness and the aluminum-oxide temperature at each axial increment. The information in this report will be used to evaluate the potential for cladding corrosion of the Mark 25 assembly.

Synthesis, characterization, and evaluation of simple aluminum-based adsorbents for fluoride removal from drinking water.

PubMed

Du, Junyi; Sabatini, David A; Butler, Elizabeth C

2014-04-01

Simple aluminum (hydr)oxides and layered double hydroxides were synthesized using common chemicals and equipment by varying synthesis temperature, concentrations of extra sulfate and citrate, and metal oxide amendments. Aluminum (hydr)oxide samples were aged at either 25 or 200°C during synthesis and, in some cases, calcined at 600 °C. Despite yielding increased crystallinity and mineral phase changes, higher temperatures had a generally negative effect on fluoride adsorption. Addition of extra sulfate during synthesis of aluminum (hydr)oxides led to significantly higher fluoride adsorption capacity compared to aluminum (hydr)oxides prepared with extra citrate or no extra ligands. X-ray diffraction results suggest that extra sulfate led to the formation of both pseudoboehmite (γ-AlOOH) and basaluminite (Al4SO4(OH)10⋅4H2O) at 200 °C; energy dispersive X-ray spectroscopy confirmed the presence of sulfur in this solid. Treatment of aluminum (hydr)oxides with magnesium, manganese, and iron oxides did not significantly impact fluoride adsorption. While layered double hydroxides exhibited high maximum fluoride adsorption capacities, their adsorption capacities at dissolved fluoride concentrations close to the World Health Organization drinking water guideline of 1.5 mg L(-1) were much lower than those for the aluminum (hydr)oxides. Copyright © 2013 Elsevier Ltd. All rights reserved.

Cadmium Alternatives High Strength Steel JTP

DTIC Science & Technology

2005-03-01

Cadmium Alternatives HSS JTP Alternative Coatings Selected by JCAT: Primary Repair LHE Cadmium (control) IVD Aluminum (control) Zinc-Nickel, acid...Tin-Zinc Cadmium Alternatives HSS JTP Demonstration Tests Selected by JCAT: Phase I Phase II Hydrogen Embrittlement Hydrogen Re-Embrittlement (NRB...immersion, exposed C-ring (Army)) Bend Adhesion (Q/A) Appearance Throwing Power Composition Uniformity Strippability Galvanic Potential Bend Adhesion

Cesium recovery from aqueous solutions

DOEpatents

Goodhall, C. A.

1960-09-13

A process for recovering cesium from aqueous solutions is given in which precipitation on zinc ferricyanide is used. The precipitation is preferably carried out in solutions containing at least 0.0004M zinc ferricyanide, an acidity ranging from 0.2N mineral acid to 0.61N acid deficiency, and 1 to 2.5M aluminum nitrate. (D.L.C.)

Failure Analysis of Alumina Reinforced Aluminum Microtruss and Tube Composites

NASA Astrophysics Data System (ADS)

Chien, Hsueh Fen (Karen)

The energy absorption capacity of cellular materials can be dramatically increased by applying a structural coating. This thesis examined the failure mechanisms of alumina reinforced 3003 aluminum alloy microtrusses and tubes. Alumina coatings were produced by hard anodizing and by plasma electrolytic oxidation (PEO). The relatively thin and discontinuous oxide coating at the hinge acted as a localized weak spot which triggered a chain reaction of failure, including oxide fracture, oxide spallation, oxide penetration to the aluminum core and severe local plastic deformation of the core. For the PEO microtrusses, delamination occurred within the oxide coating resulting in a global strut buckling failure mode. A new failure mode for the anodized tubes was observed: (i) axisymmetric folding of the aluminum core, (ii) longitudinal fracture, and (iii) alumina pulverization. Overall, the alumina coating enhanced the buckling resistance of the composites, while the aluminum core supported the oxide during the damage propagation.

40 CFR 466.32 - Effluent limitations representing the degree of effluent reduction attainable by the application...

Code of Federal Regulations, 2010 CFR

2010-07-01

...) EFFLUENT GUIDELINES AND STANDARDS PORCELAIN ENAMELING POINT SOURCE CATEGORY Aluminum Basis Material....19 5.06 0.16 Nickel 54.85 1.78 38.90 1.26 Zinc 51.74 1.68 21.79 1.71 Aluminum 176.98 5.74 72.35 2.35... Aluminum 36.25 1.18 14.82 0.48 Iron 9.80 0.32 5.02 0.16 [47 FR 53184, Nov. 24, 1982, as amended at 50 FR...

Synthesis of Hybrid Conducting Nanowire Using AAO Template

DTIC Science & Technology

2006-09-28

oxide and alujminum oxide in anodized aluminum oxide ( AAO ) template with various aspect ratio and...than 3 nm. 2. Experimentals Anodized aluminum oxide ( AAO ) template was prepared from 99.999% purity aluminum foil by performing the following...to prepare uniform dimension of nanomaterials is to use anodized alumina membrane as template. The work emphasized self-organized arrangement of

System for trapping and storing gases for subsequent chemical reduction to solids

DOEpatents

Vogel, John S [San Jose, CA; Ognibene, Ted J [Oakland, CA; Bench, Graham S [Livermore, CA; Peaslee, Graham F [Holland, MI

2009-11-03

A system for quantitatively reducing oxide gases. A pre-selected amount of zinc is provided in a vial. A tube is provided in the vial. The zinc and the tube are separated. A pre-selected amount of a catalyst is provided in the tube. Oxide gases are injected into the vial. The vial, tube, zinc, catalyst, and the oxide gases are cryogenically cooled. At least a portion of the vial, tube, zinc, catalyst, and oxide gases are heated.

High temperature resistant cermet and ceramic compositions

NASA Technical Reports Server (NTRS)

Phillips, W. M. (Inventor)

1978-01-01

Cermet compositions having high temperature oxidation resistance, high hardness and high abrasion and wear resistance, and particularly adapted for production of high temperature resistant cermet insulator bodies are presented. The compositions are comprised of a sintered body of particles of a high temperature resistant metal or metal alloy, preferably molybdenum or tungsten particles, dispersed in and bonded to a solid solution formed of aluminum oxide and silicon nitride, and particularly a ternary solid solution formed of a mixture of aluminum oxide, silicon nitride and aluminum nitride. Also disclosed are novel ceramic compositions comprising a sintered solid solution of aluminum oxide, silicon nitride and aluminum nitride.

Astaxanthin ameliorates aluminum chloride-induced spatial memory impairment and neuronal oxidative stress in mice.

PubMed

Al-Amin, Md Mamun; Reza, Hasan Mahmud; Saadi, Hasan Mahmud; Mahmud, Waich; Ibrahim, Abdirahman Adam; Alam, Musrura Mefta; Kabir, Nadia; Saifullah, A R M; Tropa, Sarjana Tarannum; Quddus, A H M Ruhul

2016-04-15

Aluminum chloride induces neurodegenerative disease in animal model. Evidence suggests that aluminum intake results in the activation of glial cells and generation of reactive oxygen species. By contrast, astaxanthin is an antioxidant having potential neuroprotective activity. In this study, we investigate the effect of astaxanthin on aluminum chloride-exposed behavioral brain function and neuronal oxidative stress (OS). Male Swiss albino mice (4 months old) were divided into 4 groups: (i) control (distilled water), (ii) aluminum chloride, (iii) astaxanthin+aluminum chloride, and (iv) astaxanthin. Two behavioral tests; radial arm maze and open field test were conducted, and OS markers were assayed from the brain and liver tissues following 42 days of treatment. Aluminum exposed group showed a significant reduction in spatial memory performance and anxiety-like behavior. Moreover, aluminum group exhibited a marked deterioration of oxidative markers; lipid peroxidation (MDA), nitric oxide (NO), glutathione (GSH) and advanced oxidation of protein products (AOPP) in the brain. To the contrary, co-administration of astaxanthin and aluminum has shown improved spatial memory, locomotor activity, and OS. These results indicate that astaxanthin improves aluminum-induced impaired memory performances presumably by the reduction of OS in the distinct brain regions. We suggest a future study to determine the underlying mechanism of astaxanthin in improving aluminum-exposed behavioral deficits. Copyright © 2016 Elsevier B.V. All rights reserved.

Self-focused ZnO transducers for ultrasonic biomicroscopy

NASA Astrophysics Data System (ADS)

Cannata, J. M.; Williams, J. A.; Zhou, Q. F.; Sun, L.; Shung, K. K.; Yu, H.; Kim, E. S.

2008-04-01

A simple fabrication technique was developed to produce high frequency (100MHz) self-focused single element transducers with sputtered zinc oxide (ZnO) crystal films. This technique requires the sputtering of a ZnO film directly onto a curved backing substrate. Transducers were fabricated by sputtering an 18μm thick ZnO layer on 2mm diameter aluminum rods with ends shaped and polished to produce a 2mm focus or f-number equal to one. The aluminum rod served a dual purpose as the backing layer and positive electrode for the resultant transducers. A 4μm Parylene matching layer was deposited on the transducers after housing and interconnect. This matching layer was used to protect the substrate and condition the transfer of acoustic energy between the ZnO film and the load medium. The pulse-echo response for a representative transducer was centered at 101MHz with a -6dB bandwidth of 49%. The measured two way insertion loss was 44dB. A tungsten wire phantom and an adult zebrafish eye were imaged to show the capability of these transducers.

Nanoscale lamellar photoconductor hybrids and methods of making same

DOEpatents

Stupp, Samuel I; Goldberger, Josh; Sofos, Marina

2013-02-05

An article of manufacture and methods of making same. In one embodiment, the article of manufacture has a plurality of zinc oxide layers substantially in parallel, wherein each zinc oxide layer has a thickness d.sub.1, and a plurality of organic molecule layers substantially in parallel, wherein each organic molecule layer has a thickness d.sub.2 and a plurality of molecules with a functional group that is bindable to zinc ions, wherein for every pair of neighboring zinc oxide layers, one of the plurality of organic molecule layers is positioned in between the pair of neighboring zinc oxide layers to allow the functional groups of the plurality of organic molecules to bind to zinc ions in the neighboring zinc oxide layers to form a lamellar hybrid structure with a geometric periodicity d.sub.1+d.sub.2, and wherein d.sub.1 and d.sub.2 satisfy the relationship of d.sub.1.ltoreq.d.sub.2.ltoreq.3d.sub.1.

Facile hydrothermal growth graphene/ZnO nanocomposite for development of enhanced biosensor.

PubMed

Low, Sze Shin; Tan, Michelle T T; Loh, Hwei-San; Khiew, Poi Sim; Chiu, Wee Siong

2016-01-15

Graphene/zinc oxide nanocomposite was synthesised via a facile, green and efficient approach consisted of novel liquid phase exfoliation and solvothermal growth for sensing application. Highly pristine graphene was synthesised through mild sonication treatment of graphite in a mixture of ethanol and water at an optimum ratio. The X-ray diffractometry (XRD) affirmed the hydrothermal growth of pure zinc oxide nanoparticles from zinc nitrate hexahydrate precursor. The as-prepared graphene/zinc oxide (G/ZnO) nanocomposite was characterised comprehensively to evaluate its morphology, crystallinity, composition and purity. All results clearly indicate that zinc oxide particles were homogenously distributed on graphene sheets, without any severe aggregation. The electrochemical performance of graphene/zinc oxide nanocomposite-modified screen-printed carbon electrode (SPCE) was evaluated using cyclic voltammetry (CV) and amperometry analysis. The resulting electrode exhibited excellent electrocatalytic activity towards the reduction of hydrogen peroxide (H2O2) in a linear range of 1-15 mM with a correlation coefficient of 0.9977. The sensitivity of the graphene/zinc oxide nanocomposite-modified hydrogen peroxide sensor was 3.2580 μAmM(-1) with a limit of detection of 7.4357 μM. An electrochemical DNA sensor platform was then fabricated for the detection of Avian Influenza H5 gene based on graphene/zinc oxide nanocomposite. The results obtained from amperometry study indicate that the graphene/zinc oxide nanocomposite-enhanced electrochemical DNA biosensor is significantly more sensitive (P < 0.05) and efficient than the conventional agarose gel electrophoresis. Copyright © 2015 Elsevier B.V. All rights reserved.

Metals in wine--impact on wine quality and health outcomes.

PubMed

Tariba, Blanka

2011-12-01

Metals in wine can originate from both natural and anthropogenic sources, and its concentration can be a significant parameter affecting consumption and conservation of wine. Since metallic ions have important role in oxide-reductive reactions resulting in wine browning, turbidity, cloudiness, and astringency, wine quality depends greatly on its metal composition. Moreover, metals in wine may affect human health. Consumption of wine may contribute to the daily dietary intake of essential metals (i.e., copper, iron, and zinc) but can also have potentially toxic effects if metal concentrations are not kept under allowable limits. Therefore, a strict analytical control of metal concentration is required during the whole process of wine production. This article presents a critical review of the existing literature regarding the measured metal concentration in wine, methods applied for their determination, and possible sources, as well as their impact on wine quality and human health. The main focus is set on aluminum, arsenic, cadmium, chromium, copper, iron, manganese, nickel, lead, and zinc, as these elements most often affect wine quality and human health.

Ceramic microstructure and adhesion

NASA Technical Reports Server (NTRS)

Buckley, D. H.

1984-01-01

When a ceramic is brought into contact with a ceramic, a polymer, or a metal, strong bond forces can develop between the materials. The bonding forces will depend upon the state of the surfaces, cleanliness and the fundamental properties of the two solids, both surface and bulk. Adhesion between a ceramic and another solid are discussed from a theoretical consideration of the nature of the surfaces and experimentally by relating bond forces to interface resulting from solid state contact. Surface properties of ceramics correlated with adhesion include, orientation, reconstruction and diffusion as well as the chemistry of the surface specie. Where a ceramic is in contact with a metal their interactive chemistry and bond strength is considered. Bulk properties examined include elastic and plastic behavior in the surficial regions, cohesive binding energies, crystal structures and crystallographic orientation. Materials examined with respect to interfacial adhesive interactions include silicon carbide, nickel zinc ferrite, manganese zinc ferrite, and aluminum oxide. The surfaces of the contacting solids are studied both in the atomic or molecularly clean state and in the presence of selected surface contaminants.

Ceramic microstructure and adhesion

NASA Technical Reports Server (NTRS)

Buckley, D. H.

1985-01-01

When a ceramic is brought into contact with a ceramic, a polymer, or a metal, strong bond forces can develop between the materials. The bonding forces will depend upon the state of the surfaces, cleanliness and the fundamental properties of the two solids, both surface and bulk. Adhesion between a ceramic and another solid are discussed from a theoretical consideration of the nature of the surfaces and experimentally by relating bond forces to interface resulting from solid state contact. Surface properties of ceramics correlated with adhesion include, orientation, reconstruction and diffusion as well as the chemistry of the surface specie. Where a ceramic is in contact with a metal their interactive chemistry and bond strength is considered. Bulk properties examined include elastic and plastic behavior in the surficial regions, cohesive binding energies, crystal structures and crystallographic orientation. Materials examined with respect to interfacial adhesive interactions include silicon carbide, nickel zinc ferrite, manganese zinc ferrite, and aluminum oxide. The surfaces of the contacting solids are studied both in the atomic or molecularly clean state and in the presence of selected surface contaminants.

Possibilities of practical usage of dispersed aluminim oxidation by liquid water

NASA Astrophysics Data System (ADS)

Larichev, M. N.; Laricheva, O. O.; Shaitura, N. S.; Shkolnikov, E. I.

2012-12-01

The goal of this work is to show the possibility of practical usage of the environmentally pure oxidation process of preliminarily dispersed aluminum (aluminum powders of the ASD or PAD grade according to TU (Technical Specifications) 48-5-226-87, which are serially produced in industry) with liquid water in order to obtain gaseous hydrogen in volumes sufficient to provide the operation of energizers based on airhydrogen fuel cells (AHFC) for portable and stationary devices (up to 3 kW). It is shown that the synthesis of aluminum oxides-hydroxides with the specified phase and chemical compositions as well as the particle shape and size can be provided simultaneously with producing commercial hydrogen. The practical usage of hydrogen, which is formed in the oxidation reaction of metallic aluminum with liquid water at pressures close to atmospheric (particularly, to service AHFCs), requires reaction intensification to increase the oxidation rate of aluminum. In this work, we considered the aspects of practical implementation of thermal, ultrasonic, and chemical activation as well as their combinations for this purpose. As the chemical activator of oxidation, we used the additives of calcium oxide (<5% of the mass of oxidized aluminum). Application of each activation method affects the phase and chemical compositions as well as the structure of formed aluminum hydroxides, which provides the possibility of their reproducible production. Thus, simultaneously with the production of commercial hydrogen, solid oxidation products satisfying the needs of industry in aluminum oxides and having the specified composition, purity, and particle shape and size can be synthesized. The acquired experimental results and elements of the design of specially developed industrial apparatuses, which were used when performing this work, can be applied when designing the model of the hydrogen generator—the prototype of the hydrogen generator for portable and stationary devices or devices of the corresponding productivity for manufacturing commercial aluminum oxides.

Liquid-Like, Self-Healing Aluminum Oxide during Deformation at Room Temperature

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Yang; Kushima, Akihiro; Han, Weizhong

Effective protection from environmental degradation relies on the integrity of oxide as diffusion barriers. Ideally, the passivation layer can repair its own breaches quickly under deformation. While studies suggest that the native aluminum oxide may manifest such properties, it has yet to be experimentally proven because direct observations of the air-environmental deformation of aluminum oxide and its initial formation at room temperature are challenging. In this letter, we report in situ experiments to stretch pure aluminum nanotips under O 2 gas environments in a transmission electron microscope (TEM). We discovered that aluminum oxide indeed deforms like liquid and can matchmore » the deformation of Al without any cracks/spallation at moderate strain rate. At higher strain rate, we exposed fresh metal surface, and visualized the self-healing process of aluminum oxide at atomic resolution. Unlike traditional thin-film growth or nanoglass consolidation processes, we observe seamless coalescence of new oxide islands without forming any glass–glass interface or surface grooves, indicating greatly accelerated glass kinetics at the surface compared to the bulk.« less

Liquid-Like, Self-Healing Aluminum Oxide during Deformation at Room Temperature

DOE PAGES

Yang, Yang; Kushima, Akihiro; Han, Weizhong; ...

2018-02-28

Effective protection from environmental degradation relies on the integrity of oxide as diffusion barriers. Ideally, the passivation layer can repair its own breaches quickly under deformation. While studies suggest that the native aluminum oxide may manifest such properties, it has yet to be experimentally proven because direct observations of the air-environmental deformation of aluminum oxide and its initial formation at room temperature are challenging. In this letter, we report in situ experiments to stretch pure aluminum nanotips under O 2 gas environments in a transmission electron microscope (TEM). We discovered that aluminum oxide indeed deforms like liquid and can matchmore » the deformation of Al without any cracks/spallation at moderate strain rate. At higher strain rate, we exposed fresh metal surface, and visualized the self-healing process of aluminum oxide at atomic resolution. Unlike traditional thin-film growth or nanoglass consolidation processes, we observe seamless coalescence of new oxide islands without forming any glass–glass interface or surface grooves, indicating greatly accelerated glass kinetics at the surface compared to the bulk.« less

Effects of stress from mine drainage on diversity, biomass, and function of primary producers in mountain streams

USGS Publications Warehouse

Niyogi, Dev K.; Lewis, William M.; McKnight, Diane M.

2002-01-01

This paper proposes a hypothesis that relates biodi- versity, community biomass, and ecosystem func- tion to a gradient of stress. According to this hy- pothesis, biodiversity has a low threshold of response to stress, whereas biomass and function are stable or increase under low to moderate stress and decrease only under high stress. This hypothe- sis was tested by examining communities of pri- mary producers in streams under stress from mine drainage in the Rocky Mountains of Colorado, USA. Mine drainage exerts chemical stress (low pH, dis- solved metals) as well as physical stress (deposition of metal oxides) on stream biota. Diversity of pri- mary producers was usually more sensitive to stress from mine drainage than community biomass (chlorophyll a) or primary production. Diversity was negatively related to all stresses from mine drainage, but it was especially low in streams with low pH or high concentration of dissolved zinc. Biomass and production were high in streams with only chemical stress, but they were often low in streams with physical stress caused by metal oxide deposition. Stream sites with aluminum oxide dep- osition usually had very little algal biomass. The rate of metal oxide deposition, presence of alumi- num oxides, and pH together explained 65% of the variation in biomass. The rate of net primary pro- duction was highly correlated with biomass and had a similar response to stress from mine drainage. Overall, chemical stresses (low pH, high concentra- tion of zinc) generally led to the hypothesized trends in our model of ecosystems under stress. Physical stress (deposition of metal oxides), how- ever, led to variable responses, and often decreased biomass and function even at low intensity, con- trary to the original hypothesis. Thus, the nature of ecosystem response to stress may differ for chemical and physical stresses

Topical zinc oxide vs. salicylic acid-lactic acid combination in the treatment of warts.

PubMed

Khattar, Joe A; Musharrafieh, Umayya M; Tamim, Hala; Hamadeh, Ghassan N

2007-04-01

Warts are a common dermatologic problem. Treatment is painful, prolonged, and can cause scarring. To evaluate topical zinc oxide for the treatment of warts. This was a randomized, double-blind controlled trial of 44 patients. Twenty-two patients were given topical zinc oxide 20% ointment, and the other 22 received salicylic acid 15% + lactic acid 15% ointment twice daily. All patients were followed up for 3 months or until cure, whichever occurred first. All patients were observed for side-effects. Sixteen patients in the zinc group and 19 in the salicylic acid-lactic acid group completed the study. In the zinc oxide-treated group, 50% of the patients showed complete cure and 18.7% failed to respond, compared with 42% and 26%, respectively, in the salicylic acid-lactic acid-treated group. No patients developed serious side-effects. Topical zinc oxide is an efficacious, painless, and safe therapeutic option for wart treatment.

Heterostructured nanohybrid of zinc oxide-montmorillonite clay.

PubMed

Hur, Su Gil; Kim, Tae Woo; Hwang, Seong-Ju; Hwang, Sung-Ho; Yang, Jae Hun; Choy, Jin-Ho

2006-02-02

We have synthesized heterostructured zinc oxide-aluminosilicate nanohybrids through a hydrothermal reaction between the colloidal suspension of exfoliated montmorillonite nanosheets and the sol solution of zinc acetate. According to X-ray diffraction, N2 adsorption-desorption isotherm, and field emission-scanning electron microscopic analyses, it was found that the intercalation of zinc oxide nanoparticles expands the basal spacing of the host montmorillonite clay, and the crystallites of the nanohybrids are assembled to form a house-of-cards structure. From UV-vis spectroscopic investigation, it becomes certain that calcined nanohybrid contains two kinds of the zinc oxide species in the interlayer space of host lattice and in mesopores formed by the house-of-cards type stacking of the crystallites. Zn K-edge X-ray absorption near-edge structure/extended X-ray absorption fine structure analyses clearly demonstrate that guest species in the nanohybrids exist as nanocrystalline zinc oxides with wurzite-type structure.

Model for thickness dependence of mobility and concentration in highly conductive zinc oxide

NASA Astrophysics Data System (ADS)

Look, David C.; Leedy, Kevin D.; Kiefer, Arnold; Claflin, Bruce; Itagaki, Naho; Matsushima, Koichi; Surhariadi, Iping

2013-03-01

The dependences of the 294 and 10 K mobility μ and volume carrier concentration n on thickness (d=25 to 147 nm) are examined in aluminum-doped zinc oxide (AZO). Two AZO layers are grown at each thickness, one with and one without a 20-nm-thick ZnON buffer layer. Plots of the 10 K sheet concentration ns versus d for buffered (B) and unbuffered (UB) samples give straight lines of similar slope, n=8.36×1020 and 8.32×1020 cm-3, but different x-axis intercepts, δd=-4 and +13 nm, respectively. Plots of ns versus d at 294 K produce substantially the same results. Plots of μ versus d can be well fitted with the equation μ(d)=μ(∞)/[1+d*/(d-δd)], where d* is the thickness for which μ(∞) is reduced by a factor 2. For the B and UB samples, d*=7 and 23 nm, respectively, showing the efficacy of the ZnON buffer. Finally, from n and μ(∞) we can use degenerate electron scattering theory to calculate bulk donor and acceptor concentrations of 1.23×1021 cm-3 and 1.95×1020 cm-3, respectively, and Drude theory to predict a plasmonic resonance at 1.34 μm. The latter is confirmed by reflectance measurements.

Trace metals and oxidative status in soft tissues of caged mussels (Aulacomya atra) on the North Patagonian coastline.

PubMed

Ruiz, M D; Iriel, A; Yusseppone, M S; Ortiz, N; Di Salvatore, P; Fernández Cirelli, A; Ríos de Molina, M C; Calcagno, J A; Sabatini, S E

2018-07-15

This study investigated metal accumulation and oxidative effects in mantle, gill and digestive gland of the ribbed mussel Aulacomya atra from the Argentinean North Patagonian coastline. Mussels were transplanted over an 18-month period from a site with low anthropogenic impact to a harbor site with higher seawater concentration of aluminum, chromium, copper, manganese, nickel and zinc. Total trace metal concentration in seawater did not change throughout the 18-month transplant in either site. A. atra bioaccumulated metals in digestive gland, gills and mantle at different levels. Digestive gland had the highest concentration of metals, especially towards the end of the transplant experiment in the harbor area. Mussels transplanted to the harbor site experienced an upregulation in their antioxidant system, which likely explains the lack of oxidative damage to lipids despite higher metal accumulation. These results demonstrate that A. atra selectively accumulates metals from the water column and their prooxidant effects depend on the tissue antioxidant defenses and the exposure time. Copyright © 2018 Elsevier Inc. All rights reserved.

Fabrication of silver nanowires and metal oxide composite transparent electrodes and their application in UV light-emitting diodes

NASA Astrophysics Data System (ADS)

Yan, Xingzhen; Ma, Jiangang; Xu, Haiyang; Wang, Chunliang; Liu, Yichun

2016-08-01

In this paper, we prepared the silver nanowires (AgNWs)/aluminum-doped zinc oxide (AZO) composite transparent conducting electrodes for n-ZnO/p-GaN heterojunction light emitting-diodes (LEDs) by drop casting AgNW networks and subsequent atomic layer deposition (ALD) of AZO at 150 °C. The contact resistances between AgNWs were dramatically reduced by pre-annealing in the vacuum chamber before the ALD of AZO. In this case, AZO works not only as the conformal passivation layer that protects AgNWs from oxidation, but also as the binding material that improves AgNWs adhesion to substrates. Due to the localized surface plasmons (LSPs) of the AgNWs resonant coupling with the ultraviolet (UV) light emission from the LEDs, a higher UV light extracting efficiency is achieved from LEDs with the AgNWs/AZO composite electrodes in comparison with the conventional AZO electrodes. Additionally, the antireflective nature of random AgNW networks in the composite electrodes caused a broad output light angular distribution, which could be of benefit to certain optoelectronic devices like LEDs and solar cells.

Immobilization of Acidithiobacillus ferrooxidans on Cotton Gauze for the Bioleaching of Waste Printed Circuit Boards.

PubMed

Nie, Hongyan; Zhu, Nengwu; Cao, Yanlan; Xu, Zhiguo; Wu, Pingxiao

2015-10-01

The bioleaching parameters of metal concentrates from waste printed circuit boards by Acidithiobacillus ferrooxidans immobilized on cotton gauze in a two-step reactor were investigated in this study. The results indicated that an average ferrous iron oxidation rate of 0.54 g/(L·h) and a ferrous iron oxidation ratio of 96.90 % were obtained after 12 h at aeration rate of 1 L/min in bio-oxidation reactor. After 96 h, the highest leaching efficiency of copper reached 91.68 % under the conditions of the content of the metal powder 12 g/L, the retention time 6 h, and the aeration rate 1 L/min. The bioleaching efficiency of copper could be above 91.12 % under repeated continuous batch operation. Meanwhile, 95.32 % of zinc, 90.32 % of magnesium, 86.31 % of aluminum, and 59.07 % of nickel were extracted after 96 h. All the findings suggested that the recovery of metal concentrates from waste printed circuit boards via immobilization of A. ferrooxidans on cotton gauze was feasible.

Limonia acidissima L. leaf mediated synthesis of zinc oxide nanoparticles: A potent tool against Mycobacterium tuberculosis.

PubMed

Taranath, Tarikere C; Patil, Bheemanagouda N

2016-06-01

The present investigation was undertaken to synthesize zinc oxide nanoparticles using Limonia acidissima L. and to test their efficacy against the growth of Mycobacterium tuberculosis. The formation of zinc oxide nanoparticles was confirmed with UV-visible spectrophotometry. Fourier transform infrared spectroscopy shows the presence of bio-molecules involved in the stabilization of zinc oxide nanoparticles. The shape and size was confirmed with atomic force microscope, X-ray diffraction, and high resolution transmission electron microscope. These nanoparticles were tested for their effect on the growth of M. tuberculosis through the microplate alamar blue assay technique. The UV-visible data reveal that an absorbance peak at 374nm confirms formation of zinc oxide nanoparticles and they are spherical in shape with sizes between 12nm and 53nm. These nanoparticles control the growth of M. tuberculosis at 12.5μg/mL. Phytosynthesis of zinc oxide nanoparticles is a green, eco-friendly technology because it is inexpensive and pollution free. In the present investigation, based on our results we conclude that the aqueous extract of leaves of L. acidissima can be used for the synthesis of zinc oxide nanoparticles. These nanoparticles control the growth of M. tuberculosis and this was confirmed with the microplate alamar blue method. The potential of biogenic zinc oxide nanoparticles may be harnessed as a novel medicine ingredient to combat tuberculosis disease. Copyright © 2016 Asian-African Society for Mycobacteriology. Published by Elsevier Ltd. All rights reserved.

Zinc oxide crystal whiskers as a novel sorbent for solid-phase extraction of flavonoids.

PubMed

Wang, Licheng; Shangguan, Yangnan; Hou, Xiudan; Jia, Yong; Liu, Shujuan; Sun, Yingxin; Guo, Yong

2017-08-15

As a novel solid-phase extraction material, zinc oxide crystal whiskers were used to extract flavonoid compounds and showed good extraction abilities. X-ray diffraction, scanning electron microscopy with energy dispersive X-ray spectroscopy and surface area/pore volume characterized the sorbent. The zinc oxide was packed into a solid-phase extraction micro-column and its extraction ability was evaluated by four model flavonoid compounds. The sample loading and elution parameters were optimized and the zinc oxide based analytical method for flavonoids was established. It showed that the method has wide linearities from 1 to 150μg/L and low limits of detection at 0.25μg/L. The relative standard deviations of a single column repeatability and column to column reproducibility were less than 6.8% and 10.6%. Several real samples were analyzed by the established method and satisfactory results were obtained. The interactions between flavonoids and zinc oxide were calculated and proved to be from the Van der Waals' forces between the 4p and 5d orbitals from zinc atom and the neighboring π orbitals from flavonoid phenyl groups. Moreover, the zinc oxide crystal whiskers showed good stability and could be reused more than 50 times under the operation conditions. This work proves that the zinc oxide crystal whiskers are a good candidate for flavonoids enrichment. Copyright © 2017. Published by Elsevier B.V.

ZnO nanoparticle catalysts for use in biodiesel production and method of making

DOEpatents

Yan, Shuli; Salley, Steven O; Ng, K. Y. Simon

2014-11-25

A method of forming a biodiesel product and a heterogeneous catalyst system used to form said product that has a high tolerance for the presence of water and free fatty acids (FFA) in the oil feedstock is disclosed. This catalyst system may simultaneously catalyze both the esterification of FAA and the transesterification of triglycerides present in the oil feedstock. The catalyst system is comprised of a mixture of zinc oxide and a second metal oxide. The zinc oxide includes a mixture of amorphous zinc oxide and zinc oxide nanocrystals, the zinc nanocrystals having a mean grain size between about 20 and 80 nanometers with at least one of the nanocrystals including a mesopore having a diameter of about 5 to 15 nanometers. Preferably, the second metal oxide is a lanthanum oxide, the lanthanum oxide being selected as one from the group of La.sub.2CO.sub.5, LaOOH, and combinations or mixtures thereof.

21 CFR 73.1991 - Zinc oxide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Zinc oxide. 73.1991 Section 73.1991 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... coloring externally applied drugs. (b) Specifications. Zinc oxide shall conform to the following...

21 CFR 73.2991 - Zinc oxide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2991 Zinc oxide. (a) Identity and specifications. The... (a)(1) and (b). (b) Uses and restrictions. Zinc oxide may be safely used in cosmetics, including cosmetics intended for use in the area of the eye, in amounts consistent with good manufacturing practice...

Cadmium plating replacements

NASA Technical Reports Server (NTRS)

Nelson, Mary J.; Groshart, Earl C.

1995-01-01

The Boeing Company has been searching for replacements to cadmium plate. Two alloy plating systems seem close to meeting the needs of a cadmium replacement. The two alloys, zinc-nickel and tin-zinc are from alloy plating baths; both baths are neutral pH. The alloys meet the requirements for salt fog corrosion resistance, and both alloys excel as a paint base. Currently, tests are being performed on standard fasteners to compare zinc-nickel and tin-zinc on threaded hardware where cadmium is heavily used. The Hydrogen embrittlement propensity of the zinc-nickel bath has been tested, and just beginning for the tin-zinc bath. Another area of interest is the electrical properties on aluminum for tin-zinc and will be discussed. The zinc-nickel alloy plating bath is in production in Boeing Commercial Airplane Group for non-critical low strength steels. The outlook is promising that these two coatings will help The Boeing Company significantly reduce its dependence on cadmium plating.

Hydrothermal synthesis of zinc oxide nanoparticles using rice as soft biotemplate.

PubMed

Ramimoghadam, Donya; Bin Hussein, Mohd Zobir; Taufiq-Yap, Yun Hin

2013-01-01

Rice as a renewable, abundant bio-resource with unique characteristics can be used as a bio-template to synthesize various functional nanomaterials. Therefore, the effect of uncooked rice flour as bio-template on physico-chemical properties, especially the morphology of zinc oxide nanostructures was investigated in this study. The ZnO particles were synthesized through hydrothermal-biotemplate method using zinc acetate-sodium hydroxide and uncooked rice flour at various ratios as precursors at 120°C for 18 hours. The results indicate that rice as a bio-template can be used to modify the shape and size of zinc oxide particles. Different morphologies, namely flake-, flower-, rose-, star- and rod-like structures were obtained with particle size at micro- and nanometer range. Pore size and texture of the resulting zinc oxide particles were found to be template-dependent and the resulting specific surface area enhanced compared to the zinc oxide synthesized without rice under the same conditions. However, optical property particularly the band gap energy is generally quite similar. Pure zinc oxide crystals were successfully synthesized using rice flour as biotemplate at various ratios of zinc salt to rice. The size- and shape-controlled capability of rice to assemble the ZnO particles can be employed for further useful practical applications.

Effects of sub-acute exposure to TiO2, ZnO and Al2O3 nanoparticles on oxidative stress and histological changes in mouse liver and brain.

PubMed

Shrivastava, Rupal; Raza, Saimah; Yadav, Abhishek; Kushwaha, Pramod; Flora, Swaran J S

2014-07-01

Nanomaterials are at the leading edge of the rapidly developing field of nanotechnology. However the information regarding toxicity of these nanoparticles on humans and environment is still deficient. The present study investigated the toxic effects of three metal oxide nanoparticles, TiO2, ZnO and Al2O3 on mouse erythrocytes, brain and liver. Male mice were administered a single oral dose of 500 mg/kg of each nanoparticles for 21 consecutive days. The results suggest that exposure to these nano metallic particles produced a significant oxidative stress in erythrocyte, liver and brain as evident from enhanced levels of Reactive Oxygen Species (ROS) and altered antioxidant enzymes activities. A significant increase in dopamine and norepinephrine levels in brain cerebral cortex and increased brain oxidative stress suggest neurotoxic potential of these nanoparticles. Transmission electron microscopic (TEM) analysis indicated the presence of these nanoparticles inside the cytoplasm and nucleus. These changes were also supported by the inhibition of CuZnSOD and MnSOD, considered as important biomarkers of oxidative stress. The toxic effects produced by these nanoparticles were more pronounced in the case of zinc oxide, followed by aluminum oxide and titanium dioxide, respectively. The present results further suggest the involvement of oxidative stress as one of the main mechanisms involved in nanoparticles induced toxic manifestations.

21 CFR 73.1015 - Chromium-cobalt-aluminum oxide.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 1 2013-04-01 2013-04-01 false Chromium-cobalt-aluminum oxide. 73.1015 Section 73.1015 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1015 Chromium-cobalt-aluminum oxide. (a...

21 CFR 73.1015 - Chromium-cobalt-aluminum oxide.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 1 2012-04-01 2012-04-01 false Chromium-cobalt-aluminum oxide. 73.1015 Section 73.1015 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1015 Chromium-cobalt-aluminum oxide. (a...

21 CFR 73.1015 - Chromium-cobalt-aluminum oxide.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 1 2014-04-01 2014-04-01 false Chromium-cobalt-aluminum oxide. 73.1015 Section 73.1015 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR ADDITIVES EXEMPT FROM CERTIFICATION Drugs § 73.1015 Chromium-cobalt-aluminum oxide. (a...

The Integration of Nanoscale Techniques for an Improved Battery Technology

DTIC Science & Technology

2012-06-08

anodized aluminum oxide ( AAO ) membranes that were 13...nanoporous anodized aluminum oxide ( AAO ) substrate [13]. During sputtering, thickened columnar growths form around the pores of the substrate...investigates an interpenetrating network structure where ―tubes‖ of polymer electrolyte are placed in the nanopores of anodic aluminum oxide ( AAO

Structured Nanowires for Spectra-Tuned and Spectra-Multiplexed Sensing THZ Generation

DTIC Science & Technology

2015-04-08

anodic aluminum oxide membranes ( AAO ) as templates. We...nanowires were fabricated by direct current electrochemical deposition technique using diameter-modulated anodic aluminum oxide membranes ( AAO ) as...throughout this project was the technique of atomic layer deposition (ALD) into anodized alumina oxide ( AAO ) templates. Aluminum , when

21 CFR 73.1015 - Chromium-cobalt-aluminum oxide.

Code of Federal Regulations, 2010 CFR

2010-04-01

...) Identity. The color additive chromium-cobalt-aluminum oxide is a blue-green pigment obtained by calcining a... percent each) of oxides of barium, boron, silicon, and nickel. (b) Specifications. Chromium-cobalt... milliliters of 0.5 N hydrochloric acid. (c) Uses and restrictions. The color additive chromium-cobalt-aluminum...

A survey of the concentrations of eleven metals in vaccines, allergenic extracts, toxoids, blood, blood derivatives and other biological products.

PubMed

May, J C; Rains, T C; Maienthal, F J; Biddle, G N; Progar, J J

1986-10-01

Approximately 85 samples of injectable biological products regulated by the Center for Drugs and Biologics of the United States Food and Drug Administration were surveyed for the presence of 11 elements, namely aluminum, arsenic, barium, cadmium, chromium, lead, mercury, selenium, thallium and zinc, by flame and flameless methods of atomic absorption spectrometry and flame emission spectrometry. The range of products tested included whole blood, red cells, plasma, normal serum albumin, antihemophilic factor, and other products derived from blood; allergenic extracts including honey bee venom and house dust allergenic extracts; vaccines such as measles virus vaccine and typhoid vaccine; and tetanus toxoid. The metal concentrations found in the majority of these products were low or undetectable. The metal levels varied from manufacturer to manufacturer, product and lot-to-lot of the same manufacturer's products. House dust allergenic extracts had the highest concentrations of arsenic (2.4 ppm), cadmium (0.28 ppm), chromium (0.6 ppm) and lead (1.5 ppm) found in the study. A high zinc concentration (24 ppm) in an immune serum globulin was attributed to the zinc-containing rubber stopper in contact with the product. A range of 0.36-3.30 ppm aluminum was found for seven 25% normal serum albumin samples from seven manufacturers. Values of 8.2, 17 and 18 ppm aluminum were found in one manufacturer's 25% normal serum albumin. These aluminum values appeared to be the result of an anomaly in this manufacturer's production that has not been repeated to date.

Dynamics of Oxidation of Aluminum Nanoclusters using Variable Charge Molecular-Dynamics Simulations on Parallel Computers

NASA Astrophysics Data System (ADS)

Campbell, Timothy; Kalia, Rajiv K.; Nakano, Aiichiro; Vashishta, Priya; Ogata, Shuji; Rodgers, Stephen

1999-06-01

Oxidation of aluminum nanoclusters is investigated with a parallel molecular-dynamics approach based on dynamic charge transfer among atoms. Structural and dynamic correlations reveal that significant charge transfer gives rise to large negative pressure in the oxide which dominates the positive pressure due to steric forces. As a result, aluminum moves outward and oxygen moves towards the interior of the cluster with the aluminum diffusivity 60% higher than that of oxygen. A stable 40 Å thick amorphous oxide is formed; this is in excellent agreement with experiments.

Analysis of “Favorable Growth Element” Based on Rare Earth-aluminum Composite Mechanism of Compound Process

NASA Astrophysics Data System (ADS)

Hao, Baohong; Zeng, Qihui; Zhao, Jin

2018-01-01

Under the background that failure resulted in by high temperature once only aluminum oxide is used as the gasoline additive. This paper, with the purpose to solve this problem, is to synthesize AcAl oxide for gasoline additive. In order to get the rare-earth-aluminum oxide, first, a complex model of rare earth oxide based on theories about ion coordination is established. Then, by the complex model, the type of “compound growth unit” when rare earth elements join the hydrothermal conditions and the inclination that “diversification” might probably happen are deduced. Depending on the results got by complex model, this paper introduces the type of compound and its existence conditions of “Compound growth unit” owned by stable rare-earth-aluminum oxide. By adjusting the compositions of modifier, compound materials of rare earth-aluminum oxide used for gasoline additive is made. By XRD test, aperture test, adsorption test and desorption test, the theoretical deduction is proved to be right. From the experiment, it is concluded that: a dense environment is the pre-condition to form rare-earth-aluminum polymer, which is also an essential condition for the polymer to update to a favorable growth unit and produce mesoporous rare-earth-aluminum oxide with high activity.

Modeling the Shock Ignition of a Copper Oxide Aluminum Thermite

NASA Astrophysics Data System (ADS)

Lee, Kibaek; Stewart, D. Scott; Clemenson, Michael; Glumac, Nick; Murzyn, Christopher

2015-06-01

An experimental ``striker confinement'' shock compression test was developed in the Glumac-group at the University of Illinois to study ignition and reaction in composite reactive materials. These include thermitic and intermetallic reactive powders. The test places a sample of materials such as a thermite mixture of copper oxide and aluminum powders that are initially compressed to about 80 percent full density. Two RP-80 detonators simultaneously push steel bars into reactive material and the resulting compression causes shock compaction of the material and rapid heating. At that point one observes significant reaction and propagation of fronts. But the fronts are peculiar in that they are comprised of reactive events that can be traced to the reaction/diffusion of the initially separated reactants of copper oxide and aluminum that react at their mutual interfaces that nominally make copper liquid and aluminum oxide products. We discuss our model of the shock ignition of the copper oxide aluminum thermite in the context of the striker experiment and how a Gibbs formulation model, that includes multi-components for liquid and solid phases of aluminum, copper oxide, copper and aluminum oxide can predict the events observed at the particle scale in the experiments. Supported by HDTRA1-10-1-0020 (DTRA), N000014-12-1-0555 (ONR).

Zinc, a neuroprotective agent against aluminum-induced oxidative DNA injury.

PubMed

Singla, Neha; Dhawan, D K

2013-08-01

Aluminum (Al) has been considered as one of the most abundant elements and comprises nearly 8 % of the Earth's crust. Despite of its immense presence, studies regarding the molecular basis of its interaction with the physiological system are rather sparse. On the other hand, zinc (Zn), an essential micronutrient, has been regarded as the second most important metal for brain functioning. The objective of the present study was to investigate the protective potential of Zn, if any, during Al-induced detrimental effects on DNA, tritiated thymidine uptake as well as expression of stress marker genes and proteins in rat brain. Male Sprague-Dawley rats weighing 140-160 g were divided into four different groups viz.: normal control, Al treated (100 mg/kg b wt/day via oral gavage), Zn treated (227 mg/l in drinking water), and combined Al and Zn treated. All the treatments were carried out for a total duration of 8 weeks. Agarose gel electrophoresis revealed DNA laddering pattern and comets in the rat brain following Al treatment, which however, were attenuated upon Zn treatment. Further, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL)-positive cells, number of apoptotic brain cells, and uptake of tritiated thymidine were increased after Al treatment but were decreased upon Zn supplementation. Western blot and mRNA expressions of p53 and nuclear factor κB (NF-κB) were also found to be significantly elevated after Al treatment, which however, were reversed following Zn treatment. Hence, Zn shall prove to be an effective agent in mitigating the detrimental effects caused by Al in the rat brain.

Comparative studies on acid leaching of zinc waste materials

NASA Astrophysics Data System (ADS)

Rudnik, Ewa; Włoch, Grzegorz; Szatan, Leszek

2017-11-01

Three industrial waste materials were characterized in terms of their elemental and phase compositions, leaching behaviour in 10% sulfuric acid solution as well as leaching thermal effects. Slag from melting of mixed metallic scrap contained about 50% Zn and 10% Pb. It consisted mainly of various oxides and oxy-chlorides of metals. Zinc spray metallizing dust contained about 77% Zn in form of zinc and/or zinc-iron oxides, zinc metal and Zn-Fe intermetallic. Zinc ash from hot dip galvanizing was a mixture of zinc oxide, metallic zinc and zinc hydroxide chloride and contained about 80% Zn. Dissolution efficiency of zinc from the first material was 80% (independently on the solid to liquid ratio, 50-150 kg/m3), while decrease of the efficacy from 80% to 60% with increased solid to liquid ratio for the two remaining materials was observed. Both increase in the temperature (20 °C to 35 °C) and agitation rate (300 rpm to 900 rpm) did not improve seriously the leaching results. In all cases, transfer of zinc ions to the leachate was accompanied by different levels of solution contamination, depending on the type of the waste. Leaching of the materials was exothermic with the similar reaction heats for two high oxide-type products (slag, zinc ash) and higher values for the spray metallizing dust.

The Oxidation Products of Aluminum Hydride and Boron Aluminum Hydride Clusters

DTIC Science & Technology

2016-01-04

AFRL-AFOSR-VA-TR-2016-0075 The Oxidation Products of Aluminum Hydride and Boron Aluminum Hydride Clusters KIT BOWEN JOHNS HOPKINS UNIV BALTIMORE MD...Hydride and Boron Aluminum Hydride Clusters 5a.  CONTRACT NUMBER 5b.  GRANT NUMBER FA9550-14-1-0324 5c.  PROGRAM ELEMENT NUMBER 61102F 6. AUTHOR(S) KIT...of both Aluminum Hydride Cluster Anions and Boron Aluminum Hydride Cluster Anions with Oxygen: Anionic Products The anionic products of reactions

High temperature resistant cermet and ceramic compositions. [for thermal resistant insulators and refractory coatings

NASA Technical Reports Server (NTRS)

Phillips, W. M. (Inventor)

1978-01-01

High temperature oxidation resistance, high hardness and high abrasion and wear resistance are properties of cermet compositions particularly to provide high temperature resistant refractory coatings on metal substrates, for use as electrical insulation seals for thermionic converters. The compositions comprise a sintered body of particles of a high temperature resistant metal or metal alloy, preferably molybdenum or tungsten particles, dispersed in and bonded to a solid solution formed of aluminum oxide and silicon nitride, and particularly a ternary solid solution formed of a mixture of aluminum oxide, silicon nitride and aluminum nitride. Ceramic compositions comprising a sintered solid solution of aluminum oxide, silicon nitride and aluminum nitride are also described.

Effect of grit-blasting on substrate roughness and coating adhesion

NASA Astrophysics Data System (ADS)

Varacalle, Dominic J.; Guillen, Donna Post; Deason, Douglas M.; Rhodaberger, William; Sampson, Elliott

2006-09-01

Statistically designed experiments were performed to compare the surface roughness produced by grit blasting A36/1020 steel using different abrasives. Grit blast media, blast pressure, and working distance were varied using a Box-type statistical design of experiment (SDE) approach. The surface textures produced by four metal grits (HG16, HG18, HG25, and HG40) and three conventional grits (copper slag, coal slag, and chilled iron) were compared. Substrate roughness was measured using surface profilometry and correlated with operating parameters. The HG16 grit produced the highest surface roughness of all the grits tested. Aluminum and zinc-aluminum coatings were deposited on the grit-blasted substrates using the twin-wire electric are (TWEA) process. Bond strength of the coatings was measured with a portable adhesion tester in accordance with ASTM standard D 4541. The coatings on substrates roughened with steel grit exhibit superior bond strength to those prepared with conventional grit. For aluminum coatings sprayed onto surfaces prepared with the HG16 grit, the bond strength was most influenced by current, spray distance, and spray gun pressure (in that order). The highest bond strength for the zinc-aluminum coatings was attained on surfaces prepared using the metal grits.

The development of latent fingerprints by zinc oxide and tin oxide nanoparticles prepared by precipitation technique

NASA Astrophysics Data System (ADS)

Luthra, Deepali; Kumar, Sacheen

2018-05-01

Fingerprints are the very important evidence at the crime scene which must be developed clearly with shortest duration of time to solve the case. Metal oxide nanoparticles could be the mean to develop the latent fingerprints. Zinc oxide and Tin Oxide Nanoparticles were prepared by using chemical precipitation technique which were dried and characterized by X-ray diffraction, UV-Visible spectroscopy and FTIR. The size of zinc oxide crystallite was found to be 14.75 nm with minimum reflectance at 360 nm whereas tin oxide have the size of 90 nm and reflectance at minimum level 321 nm. By using these powdered samples on glass, plastic and glossy cardboard, latent fingerprints were developed. Zinc oxide was found to be better candidate than tin oxide for the fingerprint development on all the three types of substrates.

Cadmium-free junction fabrication process for CuInSe.sub.2 thin film solar cells

DOEpatents

Ramanathan, Kannan V.; Contreras, Miguel A.; Bhattacharya, Raghu N.; Keane, James; Noufi, Rommel

1999-01-01

The present invention provides an economical, simple, dry and controllable semiconductor layer junction forming process to make cadmium free high efficiency photovoltaic cells having a first layer comprised primarily of copper indium diselenide having a thin doped copper indium diselenide n-type region, generated by thermal diffusion with a group II(b) element such as zinc, and a halide, such as chlorine, and a second layer comprised of a conventional zinc oxide bilayer. A photovoltaic device according the present invention includes a first thin film layer of semiconductor material formed primarily from copper indium diselenide. Doping of the copper indium diselenide with zinc chloride is accomplished using either a zinc chloride solution or a solid zinc chloride material. Thermal diffusion of zinc chloride into the copper indium diselenide upper region creates the thin n-type copper indium diselenide surface. A second thin film layer of semiconductor material comprising zinc oxide is then applied in two layers. The first layer comprises a thin layer of high resistivity zinc oxide. The second relatively thick layer of zinc oxide is doped to exhibit low resistivity.

21 CFR 73.2991 - Zinc oxide.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 1 2011-04-01 2011-04-01 false Zinc oxide. 73.2991 Section 73.2991 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... color additive zinc oxide shall conform in identity and specifications to the requirements of § 73.1991...

21 CFR 182.8991 - Zinc oxide.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Zinc oxide. 182.8991 Section 182.8991 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8991 Zinc oxide. (a) Product...

21 CFR 182.8991 - Zinc oxide.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Zinc oxide. 182.8991 Section 182.8991 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) SUBSTANCES GENERALLY RECOGNIZED AS SAFE Nutrients § 182.8991 Zinc oxide. (a) Product...

Zinc oxide nanorod clusters deposited seaweed cellulose sheet for antimicrobial activity.

PubMed

Bhutiya, Priyank L; Mahajan, Mayur S; Abdul Rasheed, M; Pandey, Manoj; Zaheer Hasan, S; Misra, Nirendra

2018-06-01

Seaweed cellulose was isolated from green seaweed Ulva fasciata using a common bleaching agent. Sheet containing porous mesh was prepared from the extracted seaweed crystalline cellulose along with zinc oxide (ZnO) nanorod clusters grown over the sheet by single step hydrothermal method. Seaweed cellulose and zinc oxide nanorod clusters deposited seaweed cellulose sheet was characterized by FT-IR, XRD, TGA, and SEM-EDX. Morphology showed that the diameter of zinc oxide nanorods were around 70nm. Zinc oxide nanorod clusters deposited on seaweed cellulose sheet gave remarkable antibacterial activity towards gram-positive (Staphylococcus aureus, Bacillus ceresus, Streptococcus thermophilis) and gram-negative (Escherichia coli, Pseudomonas aeruginous) microbes. Such deposited sheet has potential applications in pharmaceutical, biomedical, food packaging, water treatment and biotechnological industries. Copyright © 2018 Elsevier B.V. All rights reserved.

Electron spectroscopy imaging and surface defect configuration of zinc oxide nanostructures under different annealing ambient

NASA Astrophysics Data System (ADS)

Ann, Ling Chuo; Mahmud, Shahrom; Bakhori, Siti Khadijah Mohd

2013-01-01

In this study, electron spectroscopy imaging was used to visualize the elemental distribution of zinc oxide nanopowder. Surface modification in zinc oxide was done through annealing treatment and type of surface defect was also inferred from the electron spectroscopy imaging investigation. The micrographs revealed the non-stoichiometric distribution of the elements in the unannealed samples. Annealing the samples in nitrogen and oxygen ambient at 700 °C would alter the density of the elements in the samples as a result of removal or absorption of oxygen. The electrical measurement showed that nitrogen annealing treatment improved surface electrical conductivity, whereas oxygen treatment showed an adverse effect. Observed change in the photoluminescence green emission suggested that oxygen vacancies play a significant role as surface defects. Structural investigation carried out through X-ray diffraction revealed the polycrystalline nature of both zinc oxide samples with hexagonal phase whereby annealing process increased the crystallinity of both zinc oxide specimens. Due to the different morphologies of the two types of zinc oxide nanopowders, X-ray diffraction results showed different stress levels in their structures and the annealing treatment give significant effect to the structural stress. Electron spectroscopy imaging was a useful technique to identify the elemental distribution as well as oxygen defect in zinc oxide nanopowder.

Utilization of Aluminum Waste with Hydrogen and Heat Generation

NASA Astrophysics Data System (ADS)

Buryakovskaya, O. A.; Meshkov, E. A.; Vlaskin, M. S.; Shkolnokov, E. I.; Zhuk, A. Z.

2017-10-01

A concept of energy generation via hydrogen and heat production from aluminum containing wastes is proposed. The hydrogen obtained by oxidation reaction between aluminum waste and aqueous solutions can be supplied to fuel cells and/or infrared heaters for electricity or heat generation in the region of waste recycling. The heat released during the reaction also can be effectively used. The proposed method of aluminum waste recycling may represent a promising and cost-effective solution in cases when waste transportation to recycling plants involves significant financial losses (e.g. remote areas). Experiments with mechanically dispersed aluminum cans demonstrated that the reaction rate in alkaline solution is high enough for practical use of the oxidation process. In theexperiments aluminum oxidation proceeds without any additional aluminum activation.

Template-Growth of Highly Ordered Carbon Nanotube Arrays on Silicon POSTPRINT

DTIC Science & Technology

2006-09-01

packed uni- form CNTs that are spatially isolated from each other is to use a growth template. Highly ordered anodic aluminum oxide ( AAO ) template can...process for evaporating thick aluminum of high quality and good adhesion. 15. SUBJECT TERMS Anodic Aluminum Oxide Template, Carbon Nanotubes (CNTs...within the highly ordered nanopores of an alumina oxide template, which is in turn formed on silicon through anodization of aluminum of unprecedented

Relations of benthic macroinvertebrates to concentrations of trace elements in water, streambed sediments, and transplanted bryophytes and stream habitat conditions in nonmining and mining areas of the upper Colorado River basin, Colorado, 1995-98

USGS Publications Warehouse

Mize, Scott V.; Deacon, Jeffrey R.

2002-01-01

Intensive mining activity and highly mineralized rock formations have had significant impacts on surface-water and streambed-sediment quality and aquatic life within the upper reaches of the Uncompahgre River in western Colorado. A synoptic study by the U.S. Geological Survey National Water-Quality Assessment Program was completed in the upper Uncompahgre River Basin in 1998 to better understand the relations of trace elements (with emphasis on aluminum, arsenic, copper, iron, lead, and zinc concentrations) in water, streambed sediment, and aquatic life. Water-chemistry, streambed-sediment, and benthic macroinvertebrate samples were collected during low-flow conditions between October 1995 and July 1998 at five sites on the upper Uncompahgre River, all downstream from historical mining, and at three sites in drainage basins of the Upper Colorado River where mining has not occurred. Aquatic bryophytes were transplanted to all sites for 15 days of exposure to the water column during which time field parameters were measured and chemical water-quality and benthic macroinvertebrate samples were collected. Stream habitat characteristics also were documented at each site. Certain attributes of surface-water chemistry among streams were significantly different. Concentrations of total aluminum, copper, iron, lead, and zinc in the water column and concentrations of dissolved aluminum, copper, and zinc were significantly different between nonmining and mining sites. Some sites associated with mining exceeded Colorado acute aquatic-life standards for aluminum, copper, and zinc and exceeded Colorado chronic aquatic-life standards for aluminum, copper, iron, lead, and zinc. Concentrations of copper, lead, and zinc in streambed sediments were significantly different between nonmining and mining sites. Generally, concentrations of arsenic, copper, lead, and zinc in streambed sediments at mining sites exceeded the Canadian Sediment Quality Guidelines probable effect level (PEL), except at two mining sites where concentrations of copper and zinc were below the PEL. Concentrations of arsenic, copper, iron, and lead in transplanted bryophytes were significantly different between nonmining and mining sites. Bioconcentration factors calculated for 15-day exposure using one-half of the minimum reporting level were significantly different between nonmining and mining sites. In general, concentrations of trace elements in streambed sediment and transplanted bryophytes were more closely correlated than were the concentrations of trace elements in the water column with streambed sediments or concentrations in the water column with transplanted bryophytes. Stream habitat was rated as optimal to suboptimal using the U.S. Environmental Protection Agency Rapid Bioassessment Protocols for all sites in the study area. Generally, stream habitat conditions were similar at nonmining compared to mining sites and were suitable for diverse macroinvertebrate communities. All study sites had optimal instream habitat except two mining sites with suboptimal instream habitat because of disturbances in stream habitat. The benthic macroinvertebrate community composition at nonmining sites and mining sites differed. Mining sites had significantly lower total abundance of macroinvertebrates, fewer numbers of taxa, and lower dominance of Ephemeroptera (mayflies), Plecoptera (stoneflies), and Trichoptera (caddisflies), and a larger percentage of tolerant species than did nonmining sites. The predominance of Baetis sp. (mayflies), Hydropsychidae (caddisflies), and large percentage of Orthocladiinae chironomids (midges) at mining sites indicated that these species may be tolerant to elevated trace-element concentrations. The absence of Heptageniidae (mayflies), Chloroperlidae (stoneflies), and Rhyacophila sp. (caddisflies) at mining sites indicated that these species may be sensitive to elevated trace-element concentrations. Comparison of field parameters and

Plasma in-liquid method for reduction of zinc oxide in zinc nanoparticle synthesis

NASA Astrophysics Data System (ADS)

Amaliyah, Novriany; Mukasa, Shinobu; Nomura, Shinfuku; Toyota, Hiromichi; Kitamae, Tomohide

2015-02-01

Metal air-batteries with high-energy density are expected to be increasingly applied in electric vehicles. This will require a method of recycling air batteries, and reduction of metal oxide by generating plasma in liquid has been proposed as a possible method. Microwave-induced plasma is generated in ethanol as a reducing agent in which zinc oxide is dispersed. Analysis by energy-dispersive x-ray spectrometry (EDS) and x-ray diffraction (XRD) reveals the reduction of zinc oxide. According to images by transmission electron microscopy (TEM), cubic and hexagonal metallic zinc particles are formed in sizes of 30 to 200 nm. Additionally, spherical fiber flocculates approximately 180 nm in diameter are present.

Formation of ZnO at zinc oxidation by near- and supercritical water under the constant electric field

NASA Astrophysics Data System (ADS)

Shishkin, A. V.; Sokol, M. Ya.; Shatrova, A. V.; Fedyaeva, O. N.; Vostrikov, A. A.

2014-12-01

The work has detected an influence of a constant electric field (up to E = 300 kV/m) on the structure of a nanocrystalline layer of zinc oxide, formed on the surface of a planar zinc anode in water under supercritical (673 K and 23 MPa) and near-critical (673 K and 17. 5 MPa) conditions. The effect of an increase of zinc oxidation rate with an increase in E is observed under supercritical conditions and is absent at near-critical ones. Increase in the field strength leads to the formation of a looser structure in the inner part of the zinc oxide layer.

Nuclear microprobe investigation of the penetration of ultrafine zinc oxide into intact and tape-stripped human skin

NASA Astrophysics Data System (ADS)

Szikszai, Z.; Kertész, Zs.; Bodnár, E.; Major, I.; Borbíró, I.; Kiss, Á. Z.; Hunyadi, J.

2010-06-01

Ultrafine metal oxides, such as titanium dioxide and zinc oxide are widely used in cosmetic and health products like sunscreens. These oxides are potent UV filters and the small particle size makes the product more transparent compared to formulations containing coarser particles. In the present work the penetration of ultrafine zinc oxide into intact and tape-stripped human skin was investigated using nuclear microprobe techniques, such as proton induced X-ray spectroscopy and scanning transmission ion microscopy. Our results indicate that the penetration of ultrafine zinc oxide, in a hydrophobic basis gel with 48 h application time, is limited to the stratum corneum layer of the intact skin. Removing the stratum corneum partially or entirely by tape-stripping did not cause the penetration of the particles into the deeper dermal layers; the zinc particles remained on the surface of the skin.

Assessment of metal transport into and out of Terrace Reservoir, Conejos County, Colorado, April 1994 through March 1995; interim report

USGS Publications Warehouse

Ferguson, Sheryl; Edelmann, Patrick

1996-01-01

Terrace Reservoir is the primary source of water for crops and livestock in the southwestern part of the San Luis Valley in southern Colorado. Mining activities have occurred in the basin for more than 100 years, and substantial mining of gold has occurred intermittently at the Summitville Mine.Historically, the Summitville Mine site has produced highly acidic, metal-enriched water that drained from the mine site into Wightman Fork and flowed to the Alamosa River and Terrace Reservoir. In 1994, a study was begun as part of risk-assessment and remediation efforts and to evaluate metal transport into and out of Terrace Reservoir. During the study period, the pH immediately upstream from Terrace Reservoir ranged from 4.3 to 7.8. The highest pH occurred during the pre-peak snowmelt period; the lowest pH occurred during storm runoff during summer. Downstream from Terrace Reservoir, the pH ranged from 4.6 to 7.6. The highest pH occurred during the pre-peak snowmelt period, and the lowest pH occurred during summer in mid-July. A comparison of the streamflow hydrographs upstream and downstream from Terrace Reservoir indicated that there was only a small difference between the annual volume of water that entered the reservoir and the annual volume of water that was released from the reservoir. Large spatial and temporal variations in concentrations of the metals of concern occurred during the study.The median and maximum concentrations of dissolved and total aluminum, iron, copper, cadmium, manganese, and zinc were larger upstream from the reservoir than downstream from the reservoir. The largest concentrations of dissolved aluminum, iron, copper, cadmium, manganese, and zinc generally occurred between mid-June and November. Throughout the study, aluminum was transported into the reservoir predominantly in the particulate or suspended form. Downstream from the reservoir, the suspended-aluminum fraction was predominant only during the pre-peak snowmelt and peak snowmelt periods. The temporal variations in the percentage of dissolved and suspended fraction of iron and copper downstream from Terrace Reservoir were similar to the temporal variations that occurred upstream from the reservoir. During the study period, cadmium, manganese, and zinc generally were transported into and out of the reservoir predominantly in the dissolved form. Metal loads varied considerably as a result of changes in streamflow or changes in metal concentrations, or both. The largest daily loads of aluminum, iron, and manganese were transported into and out of Terrace Reservoir during the peak snowmelt period.The reservoir was a sink for an estimated 294 tons of aluminum and 596 tons of iron. However, about 68.5 tons of total aluminum and about 194 tons of total iron were transported out of the reservoir during the study period. During the study period, about 22\\x11tons of total copper remained in the reservoir, and 39 tons was transported downstream from the reservoir. About 47 tons of total manganese and 18 tons of total-zinc loads were transported out of the reservoir; the reservoir was a sink for only a small fraction of total-manganese and -zinc.

Method for the regeneration of spent molten zinc chloride

DOEpatents

Zielke, Clyde W.; Rosenhoover, William A.

1981-01-01

In a process for regenerating spent molten zinc chloride which has been used in the hydrocracking of coal or ash-containing polynuclear aromatic hydrocarbonaceous materials derived therefrom and which contains zinc chloride, zinc oxide, zinc oxide complexes and ash-containing carbonaceous residue, by incinerating the spent molten zinc chloride to vaporize the zinc chloride for subsequent condensation to produce a purified molten zinc chloride: an improvement comprising the use of clay in the incineration zone to suppress the vaporization of metals other than zinc. Optionally water is used in conjunction with the clay to further suppress the vaporization of metals other than zinc.

40 CFR 143.4 - Monitoring.

Code of Federal Regulations, 2012 CFR

2012-07-01

.... Criteria for analyzing aluminum, copper, iron, manganese, silver and zinc samples with digestion or directly without digestion, and other analytical test procedures are contained in Technical Notes on...

40 CFR 143.4 - Monitoring.

Code of Federal Regulations, 2014 CFR

2014-07-01

.... Criteria for analyzing aluminum, copper, iron, manganese, silver and zinc samples with digestion or directly without digestion, and other analytical test procedures are contained in Technical Notes on...

40 CFR 143.4 - Monitoring.

Code of Federal Regulations, 2011 CFR

2011-07-01

.... Criteria for analyzing aluminum, copper, iron, manganese, silver and zinc samples with digestion or directly without digestion, and other analytical test procedures are contained in Technical Notes on...

40 CFR 143.4 - Monitoring.

Code of Federal Regulations, 2013 CFR

2013-07-01

.... Criteria for analyzing aluminum, copper, iron, manganese, silver and zinc samples with digestion or directly without digestion, and other analytical test procedures are contained in Technical Notes on...

Development of Pinhole-Free Amorphous Aluminum Oxide Protective Layers for Biomedical Device Applications

PubMed Central

Litvinov, Julia; Wang, Yi-Ju; George, Jinnie; Chinwangso, Pawilai; Brankovic, Stanko; Willson, Richard C.; Litvinov, Dmitri

2013-01-01

This paper describes synthesis of ultrathin pinhole-free insulating aluminum oxide layers for electronic device protection in corrosive liquid environments, such as phosphate buffered saline (PBS) or clinical fluids, to enable emerging biomedical applications such as biomolecular sensors. A pinhole-free 25-nm thick amorphous aluminum oxide layer has been achieved using ultra-high vacuum DC magnetron reactive sputtering of aluminum in oxygen/argon plasma followed by oxygen plasma post-processing. Deposition parameters were optimized to achieve the best corrosion protection of lithographically defined device structures. Electrochemical deposition of copper through the aluminum oxide layers was used to detect the presence (or absence) of pinholes. FTIR, XPS, and spectroscopic ellipsometry were used to characterize the material properties of the protective layers. Electrical resistance of the copper device structures protected by the aluminum oxide layers and exposed to a PBS solution was used as a metric to evaluate the long-term stability of these device structures. PMID:23682201

Zinc-The key to preventing corrosion

USGS Publications Warehouse

Kropschot, S.J.; Doebrich, Jeff L.

2011-01-01

Centuries before it was identified as an element, zinc was used to make brass (an alloy of zinc and copper) and for medicinal purposes. Metallic zinc and zinc oxide were produced in India sometime between the 11th and 14th centuries and in China in the 17th century, although the discovery of pure metallic zinc is credited to the German chemist Andreas Marggraf, who isolated the element in 1746. Refined zinc metal is bluish-white when freshly cast; it is hard and brittle at most temperatures and has relatively low melting and boiling points. Zinc alloys readily with other metals and is chemically active. On exposure to air, it develops a thin gray oxide film (patina), which inhibits deeper oxidation (corrosion) of the metal. The metal's resistance to corrosion is an important characteristic in its use.

OP-AMPS on Flexible Substrates with Printable Materials

DTIC Science & Technology

2011-08-10

Zinc Tin Oxide Thin - Film - Transistor Enhancement...II196, 2010. [3] D. Geng, D. H. Kang, and J. Jang, "High-Performance Amorphous Indium-Gallium- Zinc - Oxide Thin - Film Transistor With a Self-Aligned...B., Dodabalapur, A., “Band transport and mobility edge in amorphous solution-processed zinc tin oxide thin - film transistors ”, Applied

Determining adaptive and adverse oxidative stress responses in human bronical epithelial cells exposed to zinc

EPA Science Inventory

Determining adaptive and adverse oxidative stress responses in human bronchial epithelial cells exposed to zincJenna M. Currier1,2, Wan-Yun Cheng1, Rory Conolly1, Brian N. Chorley1Zinc is a ubiquitous contaminant of ambient air that presents an oxidant challenge to the human lung...

Ultrasound irradiation based in-situ synthesis of star-like Tragacanth gum/zinc oxide nanoparticles on cotton fabric.

PubMed

Ghayempour, Soraya; Montazer, Majid

2017-01-01

Application of natural biopolymers for green and safe synthesis of zinc oxide nanoparticles on the textiles is a novel and interesting approach. The present study offers the use of natural biopolymer, Tragacanth gum, as the reducing, stabilizing and binding agent for in-situ synthesis of zinc oxide nanoparticles on the cotton fabric. Ultrasonic irradiation leads to clean and easy synthesis of zinc oxide nanoparticles in short-time at low-temperature. FESEM/EDX, XRD, FT-IR spectroscopy, DSC, photocatalytic activities and antimicrobial assay are used to characterize Tragacanth gum/zinc oxide nanoparticles coated cotton fabric. The analysis confirmed synthesis of star-like zinc oxide nanoparticles with hexagonal wurtzite structure on the cotton fabric with the average particle size of 62nm. The finished cotton fabric showed a good photocatalytic activity on degradation of methylene blue and 100% antimicrobial properties with inhibition zone of 3.3±0.1, 3.1±0.1 and 3.0±0.1mm against Staphylococcus aureus, Escherichia coli and Candida albicans. Copyright © 2016 Elsevier B.V. All rights reserved.

Transparent resistive switching memory using aluminum oxide on a flexible substrate

NASA Astrophysics Data System (ADS)

Yeom, Seung-Won; Shin, Sang-Chul; Kim, Tan-Young; Ha, Hyeon Jun; Lee, Yun-Hi; Shim, Jae Won; Ju, Byeong-Kwon

2016-02-01

Resistive switching memory (ReRAM) has attracted much attention in recent times owing to its fast switching, simple structure, and non-volatility. Flexible and transparent electronic devices have also attracted considerable attention. We therefore fabricated an Al2O3-based ReRAM with transparent indium-zinc-oxide (IZO) electrodes on a flexible substrate. The device transmittance was found to be higher than 80% in the visible region (400-800 nm). Bended states (radius = 10 mm) of the device also did not affect the memory performance because of the flexibility of the two transparent IZO electrodes and the thin Al2O3 layer. The conduction mechanism of the resistive switching of our device was explained by ohmic conduction and a Poole-Frenkel emission model. The conduction mechanism was proved by oxygen vacancies in the Al2O3 layer, as analyzed by x-ray photoelectron spectroscopy analysis. These results encourage the application of ReRAM in flexible and transparent electronic devices.

Interfacial Modifiers

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martin, Ina; French, Roger H.

Our project objective in the first and only Budget Period was to demonstrate the potential of nm-scale organofunctional silane coatings as a method of extending the lifetime of PV materials and devices. Specifically, the target was to double the lifetime performance of a laminated Cu(In,Ga)Se2 (CIGS) cell under real-world and accelerated aging exposure conditions. Key findings are that modification of aluminum-doped zinc oxide (AZO) films (materials used as transparent conductive oxide (TCO) top contacts) resulted in decreased degradation of optical and electrical properties under damp heat (DH) exposure compared to un-modified AZO. The most significant finding is that modification ofmore » the AZO top contact of full CIGS devices resulted in significantly improved properties under DH exposure compared to un-modified devices, by a factor of 4 after 1000 h. Results of this one-year project have demonstrated that surface functionalization is a viable pathway for extending the lifetime of state-of-the-art CIGS devices.« less

Thickness dependence of the MoO3 blocking layers on ZnO nanorod-inverted organic photovoltaic devices

PubMed Central

Wang, Mingjun; Li, Yuan; Huang, Huihui; Peterson, Eric D.; Nie, Wanyi; Zhou, Wei; Zeng, Wei; Huang, Wenxiao; Fang, Guojia; Sun, Nanhai; Zhao, Xingzhong; Carroll, David L.

2011-01-01

Organic solar cells based on vertically aligned zinc oxide nanorod arrays (ZNR) in an inverted structure of indium tin oxide (ITO)∕ZNR∕poly(3-hexylthiophene): (6,6)-phenyl C61 butyric acid methyl ester(P3HT:PCBM)∕MoO3∕aluminum(Al) were studied. We found that the optimum MoO3 layer thickness condition of 20 nm, the MoO3 can effectively decrease the probability of bimolecular recombination either at the Al interface or within the active layer itself. For this optimum condition we get a power conversion efficiency of 2.15%, a short-circuit current density of 9.02 mA∕cm2, an open-circuit voltage of 0.55V, and a fill factor of 0.44 under 100 mW∕cm2 irradiation. Our investigations also show that the highly crystallized ZNR can create short and continuous pathways for electron transport and increase the contact area between the ZNR and the organic materials. PMID:21464889

W-containing oxide layers obtained on aluminum and titanium by PEO as catalysts in thiophene oxidation

NASA Astrophysics Data System (ADS)

Rudnev, V. S.; Lukiyanchuk, I. V.; Vasilyeva, M. S.; Morozova, V. P.; Zelikman, V. M.; Tarkhanova, I. G.

2017-11-01

W-containing oxide layers fabricated on titanium and aluminum alloys by Plasma electrolytic oxidation (PEO) have been tested in the reaction of the peroxide oxidation of thiophene. Samples with two types of coatings have been investigated. Coatings I contained tungsten oxide in the matrix and on the surface of amorphous silica-titania or silica-alumina layers, while coatings II comprised crystalline WO3 and/or Al2(WO4)3. Aluminum-supported catalyst containing a smallest amount of transition metals in the form of tungsten oxides and manganese oxides in low oxidation levels showed high activity and stability.

High-Temperature, Oxidation-Resistant Thermocouples

NASA Technical Reports Server (NTRS)

Smialek, James L.; Gedwill, Michael A.

1994-01-01

Aluminum substituted for rhodium, which is scarce and expensive. Electromotive force increases with aluminum content in Pt/Al leg of Pt(Pt/Al) thermocouple. Wires baked longer in aluminizing bed produce larger voltages. Thermocouples containing platinum/aluminum legs used instead of thermocouples of type R in furnaces, heat engines, and chemical reactors. Expecially suited to high-velocity oxidizing environments. Constructed as thin-film sensors on turbine blades and vanes, where pre-oxidation provides insulating film needed between thermocouple legs. Because aluminum content slowly depleted by oxidation, long-term use recommended only where maximum temperature is 1,200 degrees C or less.

Oxidation and Condensation of Zinc Fume From Zn-CO 2-CO-H 2O Streams Relevant to Steelmaking Off-Gas Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bronson, Tyler Mark; Ma, Naiyang; Zhu, Liang Zhu

Here the objective of this research was to study the condensation of zinc vapor to metallic zinc and zinc oxide solid under varying environments to investigate the feasibility of in-process separation of zinc from steelmaking off-gas dusts. Water vapor content, temperature, degree of cooling, gas composition, and initial zinc partial pressure were varied to simulate the possible conditions that can occur within steelmaking off-gas systems, limited to Zn-CO 2-CO-H 2O gas compositions. The temperature of deposition and the effect of rapidly quenching the gas were specifically studied. A homogeneous nucleation model for applicable experiments was applied to the analysis of the experimental data. It was determined that under the experimental conditions, oxidation of zinc vapor by H 2O or CO 2 does not occur above 1108 K (835 °C) even for highly oxidizing streams (CO 2/CO = 40/7). Rate expressions that correlate CO 2 and H 2O oxidation rates to gas composition, partial pressure of water vapor, temperature, and zinc partial pressure were determined to be as follows: Ratemore » $$ \\left(\\frac{mol}{m^2s}\\right) $$ = 406 exp $$ \\left(\\frac{-50.2 kJ/mol}{RT}\\right) $$ (pZnpCO 2 $-$ PCO/K eqCO 2) $$\\frac{mol}{m^2 x s}$$ Rate $$ \\left(\\frac{mol}{m^2s}\\right) $$ = 32.9 exp $$ \\left(\\frac{-13.7 kJ/mol}{RT}\\right) $$ (pZnPH 2O $-$ PH 2/K eqH 2O) $$\\frac{mol}{m^2 x s}$$. It was proven that a rapid cooling rate (500 K/s) significantly increases the ratio of metallic zinc to zinc oxide as opposed to a slow cooling rate (250 K/s). SEM analysis found evidence of heterogeneous growth of ZnO as well as of homogeneous formation of metallic zinc. The homogeneous nucleation model fit well with experiments where only metallic zinc deposited. An expanded model with rates of oxidation by CO 2 and H 2O as shown was combined with the homogenous nucleation model and then compared with experimental data. The calculated results based on the model gave a reasonable fit to the measured data. For the conditions used in this study, the rate equations for the oxidation of zinc by carbon dioxide and water vapor as well as the homogeneous nucleation model of metallic zinc were applicable for various temperatures, zinc partial pressures, CO 2:CO ratios, and H 2O partial pressures.« less

Oxidation and Condensation of Zinc Fume From Zn-CO 2-CO-H 2O Streams Relevant to Steelmaking Off-Gas Systems

DOE PAGES

Bronson, Tyler Mark; Ma, Naiyang; Zhu, Liang Zhu; ...

2017-01-23

Here the objective of this research was to study the condensation of zinc vapor to metallic zinc and zinc oxide solid under varying environments to investigate the feasibility of in-process separation of zinc from steelmaking off-gas dusts. Water vapor content, temperature, degree of cooling, gas composition, and initial zinc partial pressure were varied to simulate the possible conditions that can occur within steelmaking off-gas systems, limited to Zn-CO 2-CO-H 2O gas compositions. The temperature of deposition and the effect of rapidly quenching the gas were specifically studied. A homogeneous nucleation model for applicable experiments was applied to the analysis of the experimental data. It was determined that under the experimental conditions, oxidation of zinc vapor by H 2O or CO 2 does not occur above 1108 K (835 °C) even for highly oxidizing streams (CO 2/CO = 40/7). Rate expressions that correlate CO 2 and H 2O oxidation rates to gas composition, partial pressure of water vapor, temperature, and zinc partial pressure were determined to be as follows: Ratemore » $$ \\left(\\frac{mol}{m^2s}\\right) $$ = 406 exp $$ \\left(\\frac{-50.2 kJ/mol}{RT}\\right) $$ (pZnpCO 2 $-$ PCO/K eqCO 2) $$\\frac{mol}{m^2 x s}$$ Rate $$ \\left(\\frac{mol}{m^2s}\\right) $$ = 32.9 exp $$ \\left(\\frac{-13.7 kJ/mol}{RT}\\right) $$ (pZnPH 2O $-$ PH 2/K eqH 2O) $$\\frac{mol}{m^2 x s}$$. It was proven that a rapid cooling rate (500 K/s) significantly increases the ratio of metallic zinc to zinc oxide as opposed to a slow cooling rate (250 K/s). SEM analysis found evidence of heterogeneous growth of ZnO as well as of homogeneous formation of metallic zinc. The homogeneous nucleation model fit well with experiments where only metallic zinc deposited. An expanded model with rates of oxidation by CO 2 and H 2O as shown was combined with the homogenous nucleation model and then compared with experimental data. The calculated results based on the model gave a reasonable fit to the measured data. For the conditions used in this study, the rate equations for the oxidation of zinc by carbon dioxide and water vapor as well as the homogeneous nucleation model of metallic zinc were applicable for various temperatures, zinc partial pressures, CO 2:CO ratios, and H 2O partial pressures.« less

A room temperature strategy towards enhanced performance and bias stability of oxide thin film transistor with a sandwich structure channel layer

NASA Astrophysics Data System (ADS)

Zeng, Yong; Ning, Honglong; Zheng, Zeke; Zhang, Hongke; Fang, Zhiqiang; Yao, Rihui; Xu, Miao; Wang, Lei; Lan, Linfeng; Peng, Junbiao; Lu, Xubing

2017-04-01

Thermal annealing is a conventional and effective way to improve the bias stress stability of oxide thin film transistors (TFT) on solid substrates. However, it is still a challenge for enhancing the bias stress stability of oxide TFTs on flexible substrates by high-temperature post-treatment due to the thermal sensitivity of flexible substrates. Here, a room temperature strategy is presented towards enhanced performance and bias stability of oxide TFTs by intentionally engineering a sandwich structure channel layer consisting of a superlattice with aluminum doped zinc oxide (AZO) and Al2O3 thin films. The Al2O3/AZO/Al2O3-TFTs not only exhibit a saturation mobility of 9.27 cm2 V-1 s-1 and a linear mobility of 11.38 cm2 V-1 s-1 but also demonstrate a better bias stress stability than AZO/Al2O3-TFT. Moreover, the underlying mechanism of this enhanced electrical performance of TFTs with a sandwich structure channel layer is that the bottom Al2O3 thin films can obviously improve the crystalline phase of AZO films while decreasing electrical trapping centers and adsorption sites for undesirable molecules such as water and oxygen.

Green synthesis and characterization of zinc oxide nanoparticle using insulin plant (Costus pictus D. Don) and investigation of its antimicrobial as well as anticancer activities

NASA Astrophysics Data System (ADS)

Suresh, Joghee; Pradheesh, Ganeshan; Alexramani, Vincent; Sundrarajan, Mahalingam; Hong, Sun Ig

2018-03-01

In this work we aim to synthesize biocompatible ZnO nanoparticles from the zinc nitrate via green process using leaf extracts of the Costus pictus D. Don medicinal plant. FTIR studies confirm the presence of biomolecules and metal oxides. X-ray diffraction (XRD) structural analysis reveals the formation of pure hexagonal phase structures of ZnO nanoparticles. The surface morphologies of ZnO nanoparticles observed under a scanning electron microscope (SEM) suggest that most ZnO crystallites are hexagonal. EDX analysis confirms the presence of primarily zinc and oxygen. TEM images show that biosynthesized zinc oxide nanoparticles are hexagonal and spherical. The plausible formation mechanisms of zinc oxide nanoparticles are also predicted. The biosynthesized zinc oxide nanoparticles exhibit strong antimicrobial behavior against bacterial and fungal species when employing the agar diffusion method. Synthesized ZnO nanoparticles exhibit anticancer activity against Daltons lymphoma ascites (DLA) cells as well as antimicrobial activity against some bacterial and fungal strains.

Directed spatial organization of zinc oxide nanostructures

DOEpatents

Hsu, Julia [Albuquerque, NM; Liu, Jun [Richland, WA

2009-02-17

A method for controllably forming zinc oxide nanostructures on a surface via an organic template, which is formed using a stamp prepared from pre-defined relief structures, inking the stamp with a solution comprising self-assembled monolayer (SAM) molecules, contacting the stamp to the surface, such as Ag sputtered on Si, and immersing the surface with the patterned SAM molecules with a zinc-containing solution with pH control to form zinc oxide nanostructures on the bare Ag surface.

Electrically conductive anodized aluminum coatings

NASA Technical Reports Server (NTRS)

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.

Zinc is an Antioxidant and Anti-Inflammatory Agent: Its Role in Human Health

PubMed Central

Prasad, Ananda S.

2014-01-01

Zinc supplementation trials in the elderly showed that the incidence of infections was decreased by approximately 66% in the zinc group. Zinc supplementation also decreased oxidative stress biomarkers and decreased inflammatory cytokines in the elderly. In our studies in the experimental model of zinc deficiency in humans, we showed that zinc deficiency per se increased the generation of IL-1β and its mRNA in human mononuclear cells following LPS stimulation. Zinc supplementation upregulated A20, a zinc transcription factor, which inhibited the activation of NF-κB, resulting in decreased generation of inflammatory cytokines. Oxidative stress and chronic inflammation are important contributing factors for several chronic diseases attributed to aging, such as atherosclerosis and related cardiac disorders, cancer, neurodegeneration, immunologic disorders and the aging process itself. Zinc is very effective in decreasing reactive oxygen species (ROS). In this review, the mechanism of zinc actions on oxidative stress and generation of inflammatory cytokines and its impact on health in humans will be presented. PMID:25988117

Isomerization of Cyclooctadiene to Cyclooctyne with a Zinc/Zirconium Heterobimetallic Complex.

PubMed

Butler, Michael J; White, Andrew J P; Crimmin, Mark R

2016-06-06

Reaction of a zinc/zirconium heterobimetallic complex with 1,5-cyclooctadiene (1,5-COD) results in slow isomerization to 1,3-cyclooctadiene (1,3-COD), along with the formation of a new complex that includes a cyclooctyne ligand bridging two metal centers. While analogous magnesium/zirconium and aluminum/zirconium heterobimetallic complexes are competent for the catalytic isomerization of 1,5-COD to 1,3-COD, only in the case of the zinc species is the cyclooctyne adduct observed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Isomerization of Cyclooctadiene to Cyclooctyne with a Zinc/Zirconium Heterobimetallic Complex

PubMed Central

Butler, Michael J.; White, Andrew J. P.

2016-01-01

Abstract Reaction of a zinc/zirconium heterobimetallic complex with 1,5‐cyclooctadiene (1,5‐COD) results in slow isomerization to 1,3‐cyclooctadiene (1,3‐COD), along with the formation of a new complex that includes a cyclooctyne ligand bridging two metal centers. While analogous magnesium/zirconium and aluminum/zirconium heterobimetallic complexes are competent for the catalytic isomerization of 1,5‐COD to 1,3‐COD, only in the case of the zinc species is the cyclooctyne adduct observed. PMID:27071992

Electrical properties of aluminum contacts deposited by DC sputtering method for photovoltaic applications

NASA Astrophysics Data System (ADS)

Krawczak, Ewelina; Gułkowski, Sławomir

2017-10-01

The use of aluminum contacts is common in the process of silicon solar cells production because of low contact resistivity. It has also a great importance in thin film technology for photovoltaics, especially in copper-indium-gallium-diselenide (CIGS) devices. The final stage of CIGS cell production is the top contact deposition of high conductivity layer for lateral current collection. Such material has to be highly optically transparent as well. In order to make a contact, metal is deposited onto TCO layer with minimum shadowing to allow as much light as possible into device. The metal grid contact is being made by deposition of few microns of aluminum. The resistivity of the deposited material as well as resistance between the metal grid and TCO layer plays a great role in high quality solar cell production. This paper presents the results of four point probe conductivity analysis of Al thin films deposited by direct current (DC) magnetron sputtering method. Influence of technological parameters of the Al deposition process on sheet resistance of deposited layers has been showed. In order to obtain the lowest resistivity of the thin contact layer, optimal set of sputtering parameters, i.e. power applied, deposition time and deposition pressure was found. The resistivity of the contact between two adjacent Al metal fingers deposited onto transparent conductive Al-doped zinc oxide film has been also examined.

Study of physical properties of metal oxide nanoparticles obtained in acoustoplasma discharge

NASA Astrophysics Data System (ADS)

Bulychev, N. A.; Kazaryan, M. A.; Zakharyan, A. R.; Bodryshev, V. V.; Kirichenko, M. N.; Shevchenko, S. N.; Yakunin, V. G.; Timoshenko, V. Y.; Bychenko, A. B.

2018-04-01

Nanoparticles of tungsten, copper, iron, and zinc oxides were synthesized in acoustoplasma discharge. Their size distribution was studied by electron microscopy and laser correlation spectroscopy. Ultrasound was found to narrow significantly the size distribution width of zinc oxide nanoparticles. Water suspensions of zinc oxide nanoparticles showed photoluminescence in red and near infrared spectral ranges, which makes them a promising material for luminescent diagnostics of biological systems.

Nanoscale Probing of Electrical Signals in Biological Systems

DTIC Science & Technology

2012-03-18

Membranes Anodized aluminum oxide ( AAO ) is an ideal prototype substrate for studying ion transport through nanoporous membranes . For optimal...electrochemical microscopy, scanning ion conductance microscopy, nanoporous membranes , anodized aluminum oxide , atomic layer deposition, focused ion beam...capacity. This approach utilizes atomic layer deposition (ALD) of a thin conformal Ir film into a nanoporous anodized aluminum oxide (

Compositions of doped, co-doped and tri-doped semiconductor materials

DOEpatents

Lynn, Kelvin [Pullman, WA; Jones, Kelly [Colfax, WA; Ciampi, Guido [Watertown, MA

2011-12-06

Semiconductor materials suitable for being used in radiation detectors are disclosed. A particular example of the semiconductor materials includes tellurium, cadmium, and zinc. Tellurium is in molar excess of cadmium and zinc. The example also includes aluminum having a concentration of about 10 to about 20,000 atomic parts per billion and erbium having a concentration of at least 10,000 atomic parts per billion.

Corrosion Behavior of Sacrificial Coatings on Grade 10.9 Fasteners for Multimetal Armor Applications

DTIC Science & Technology

2013-08-01

hexavalent chromium , immersion, magniplate, trivalent chromium (TCP), bolts nonchromate, hexavalent chrome, grade 10.9 fasteners, bolt-on armor...for Testing and Materials (ASTM) B633 (4) electroplated zinc with hexavalent chromium conversion coating 2. Trivalent Chromium Process (TCP): ASTM...B633 (4) electroplated zinc with trivalent chromium conversion coating 3. AlumiPlate: Process details, entire surface electroplated with aluminum (Al

Controllable growth of aluminum nanorods using physical vapor deposition

PubMed Central

2014-01-01

This letter proposes and experimentally demonstrates that oxygen, through action as a surfactant, enables the growth of aluminum nanorods using physical vapor deposition. Based on the mechanism through which oxygen acts, the authors show that the diameter of aluminum nanorods can be controlled from 50 to 500 nm by varying the amount of oxygen present, through modulating the vacuum level, and by varying the substrate temperature. When grown under medium vacuum, the nanorods are in the form of an aluminum metal - aluminum oxide core-shell. The thickness of the oxide shell is ~2 nm as grown and is stable when maintained in ambient for 30 days or annealed in air at 475 K for 1 day. As annealing temperature is increased, the nanorod morphology remains stable while the ratio of oxide shell to metallic core increases, resulting in a fully aluminum oxide nanorod at 1,475 K. PMID:25170334

The route of liquid precursor to ZnO nanoparticles in premixed combustion spray pyrolysis

NASA Astrophysics Data System (ADS)

Widiyastuti, W.; Machmudah, Siti; Nurtono, Tantular; Winardi, Sugeng

2018-04-01

Zinc oxide nanoparticles had been successfully synthesized by premixed combustion spray pyrolysis. Zinc acetate was dissolved in distilled water was selected as a liquid precursor. Zinc nitrate was also used for comparison the effect of precursor type on the generated particles morphology and the crystallinity. The premixed combustion reaction used liquefied petroleum gas (LPG) mainly consisting of butane and propane as a fuel and compressed air used as an oxidizer. The liquid precursor was atomized using a custom two fluid nozzle to generate droplets. Then, the droplets were sprayed by the flow of air as a carrier gas into the premixed combustion reactor. The zinc precursor was decomposed to zinc oxide due to the high temperature as a result of combustion reaction inside the reactor resulting in nanoparticles formation. The particle size decreased with the increase of the fuel flow rate. In addition, it can be found that at the same flow rate of fuel, the particle size of zinc oxide synthesized using zinc nitrate is larger than that of the use of zinc acetate as a precursor.

Improvements to the strength and corrosion resistance of aluminum-magnesium-manganese alloys of near-AA5083 chemistry

NASA Astrophysics Data System (ADS)

Carroll, Mark Christopher

Aluminum alloys of the 5000 series (AI-Mg-Mn) are extremely popular in a wide range of applications that call for a balance of moderately high strength, good corrosion resistance, and light weight, all at a moderate cost. One of the most popular 5000 series alloys is designated A1-5083, containing, in addition to aluminum, approximately 4 wt% magnesium and 0.7 wt% manganese. In order to increase the range of versatility of this particular alloy, a number of modifications have been examined that will potentially improve the strength and corrosion resistance characteristics while maintaining a chemical composition that is very close to the proven 5083 alloy. The strength of the 5083-based alloys under study are investigated with two goals in mind---to maximize the potential strength characteristics in a "standard" 5083 form through changes in minor processing parameters or through minor alloying additions. Increasing the standard alloy's potential is possible through improved efficiency of "preprocessing" heat treatments that maximize the homogeneous dispersion of secondary manganese-based particles. For the modified alloy study, additions of scandium and zirconium are shown to improve strength not only by forming secondary particles in the alloy, but also through substitutional solid solution strengthening, even when added at very small levels. Corrosion resistance of these 5083-based alloys is investigated once again through minor alloying additions; specifically zinc, copper, and silver. Zinc is particularly effective in that it changes the corrosion-susceptible binary aluminum-magnesium phase that would otherwise form on grain boundaries following exposure to moderately elevated temperatures for extended periods of time to a ternary aluminum-magnesium-zinc phase. This chemical composition of this ternary phase that forms following zinc additions can be further altered through minor additions of copper and silver. By determining threshold levels for these modifications while maintaining a chemical composition that is very near that of standard Al-5083, it can be shown that even minor modifications to processing and alloying parameters can have a favorable effect on the final bulk properties of the alloy. The increased range of strength and corrosion resistance of these lightly modified alloys make them more attractive in a broadened range of potential applications.

Determination of the Mineral Composition and Toxic Element Contents of Propolis by Near Infrared Spectroscopy

PubMed Central

González-Martín, M. Inmaculada; Escuredo, Olga; Revilla, Isabel; Vivar-Quintana, Ana M.; Coello, M. Carmen; Palacios Riocerezo, Carlos; Wells Moncada, Guillermo

2015-01-01

The potential of near infrared spectroscopy (NIR) with remote reflectance fiber-optic probes for determining the mineral composition of propolis was evaluated. This technology allows direct measurements without prior sample treatment. Ninety one samples of propolis were collected in Chile (Bio-Bio region) and Spain (Castilla-León and Galicia regions). The minerals measured were aluminum, calcium, iron, potassium, magnesium, phosphorus, and some potentially toxic trace elements such as zinc, chromium, nickel, copper and lead. The modified partial least squares (MPLS) regression method was used to develop the NIR calibration model. The determination coefficient (R2) and root mean square error of prediction (RMSEP) obtained for aluminum (0.79, 53), calcium (0.83, 94), iron (0.69, 134) potassium (0.95, 117), magnesium (0.70, 99), phosphorus (0.94, 24) zinc (0.87, 10) chromium (0.48, 0.6) nickel (0.52, 0.7) copper (0.64, 0.9) and lead (0.70, 2) in ppm. The results demonstrated that the capacity for prediction can be considered good for wide ranges of potassium, phosphorus and zinc concentrations, and acceptable for aluminum, calcium, magnesium, iron and lead. This indicated that the NIR method is comparable to chemical methods. The method is of interest in the rapid prediction of potentially toxic elements in propolis before consumption. PMID:26540058

Zinc supplementation alleviates the progression of diabetic nephropathy by inhibiting the overexpression of oxidative-stress-mediated molecular markers in streptozotocin-induced experimental rats.

PubMed

Barman, Susmita; Pradeep, Seetur R; Srinivasan, Krishnapura

2018-04-01

Zinc deficiency during diabetes projects a role for zinc nutrition in the management of diabetic nephropathy. The current study explored whether zinc supplementation protects against diabetic nephropathy through modulation of kidney oxidative stress and stress-induced expression related to the inflammatory process in streptozotocin-induced diabetic rats. Groups of hyperglycemic rats were exposed to dietary interventions for 6 weeks with zinc supplementation (5 times and 10 times the normal level). Supplemental-zinc-fed diabetic groups showed a significant reversal of increased kidney weight and creatinine clearance. There was a significant reduction in hyperlipidemic condition along with improved PUFA:SFA ratio in the renal tissue. Expression of the lipid oxidative marker and expression of inflammatory markers, cytokines, fibrosis factors and apoptotic regulatory proteins observed in diabetic kidney were beneficially modulated by zinc supplementation, the ameliorative effect being concomitant with elevated antiapoptosis. There was a significant reduction in advanced glycation, expression of the receptor of the glycated products and oxidative stress markers. Zinc supplementation countered the higher activity and expression of polyol pathway enzymes in the kidney. Overexpression of the glucose transporters, as an adaptation to the increased need for glucose transport in diabetic condition, was minimized by zinc treatment. The pathological abnormalities in the renal architecture of diabetic animals were corrected by zinc intervention. Thus, dietary zinc supplementation has a significant beneficial effect in the control of diabetic nephropathy. This was exerted through a protective influence on oxidative-stress-induced cytokines, inflammatory proliferation and consequent renal injury. Copyright © 2017 Elsevier Inc. All rights reserved.

Low-temperature solution-processed zinc oxide field effect transistor by blending zinc hydroxide and zinc oxide nanoparticle in aqueous solutions

NASA Astrophysics Data System (ADS)

Shin, Hyeonwoo; Kang, Chan-mo; Baek, Kyu-Ha; Kim, Jun Young; Do, Lee-Mi; Lee, Changhee

2018-05-01

We present a novel methods of fabricating low-temperature (180 °C), solution-processed zinc oxide (ZnO) transistors using a ZnO precursor that is blended with zinc hydroxide [Zn(OH)2] and zinc oxide hydrate (ZnO • H2O) in an ammonium solution. By using the proposed method, we successfully improved the electrical performance of the transistor in terms of the mobility (μ), on/off current ratio (I on/I off), sub-threshold swing (SS), and operational stability. Our new approach to forming a ZnO film was systematically compared with previously proposed methods. An atomic forced microscopic (AFM) image and an X-ray photoelectron spectroscopy (XPS) analysis showed that our method increases the ZnO crystallite size with less OH‑ impurities. Thus, we attribute the improved electrical performance to the better ZnO film formation using the blending methods.

X-ray photoelectron spectroscopy study of the stability of Fomblin Z25 on the native oxide of aluminum

NASA Technical Reports Server (NTRS)

Herrera-Fierro, Pilar; Pepper, Stephen V.; Jones, William R.

1992-01-01

Thin films of Fomblin Z25, a perfluoropolyalkylether lubricant, were vapor deposited onto clean, oxidized aluminum, and onto sapphire surfaces, and their behavior at different temperatures was studied using X-ray photoelectron spectroscopy and temperature desorption spectroscopy (TDS). The interfacial fluid molecules decompose on the native oxide at room temperature, and continue to decompose at elevated temperatures, as previous studies had shown to occur on the clean metal. TDS indicated that different degradation mechanisms were operative for clean and oxidized aluminum. On sapphire substrates, no reaction was observed at room temperature. The native oxide of aluminum is neither passive nor protective towards Fomblin Z25. At higher temperatures (150 C), degradation of the polymer on sapphire produced a debris layer at the interface with a chemical composition similar to the one formed on aluminum oxide. Rubbing a Fomblin film on a single crystal sapphire also induced the decomposition of the lubricant in contact with the interface and the formation of a debris layer.

Properties of Zinc Oxide Nanoparticles and Their Activity Against Microbes

NASA Astrophysics Data System (ADS)

Siddiqi, Khwaja Salahuddin; ur Rahman, Aziz; Tajuddin; Husen, Azamal

2018-05-01

Zinc oxide is an essential ingredient of many enzymes, sun screens, and ointments for pain and itch relief. Its microcrystals are very efficient light absorbers in the UVA and UVB region of spectra due to wide bandgap. Impact of zinc oxide on biological functions depends on its morphology, particle size, exposure time, concentration, pH, and biocompatibility. They are more effective against microorganisms such as Bacillus subtilis, Bacillus megaterium, Staphylococcus aureus, Sarcina lutea, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, Pseudomonas vulgaris, Candida albicans, and Aspergillus niger. Mechanism of action has been ascribed to the activation of zinc oxide nanoparticles by light, which penetrate the bacterial cell wall via diffusion. It has been confirmed from SEM and TEM images of the bacterial cells that zinc oxide nanoparticles disintegrate the cell membrane and accumulate in the cytoplasm where they interact with biomolecules causing cell apoptosis leading to cell death.

Properties of Zinc Oxide Nanoparticles and Their Activity Against Microbes.

PubMed

Siddiqi, Khwaja Salahuddin; Ur Rahman, Aziz; Tajuddin; Husen, Azamal

2018-05-08

Zinc oxide is an essential ingredient of many enzymes, sun screens, and ointments for pain and itch relief. Its microcrystals are very efficient light absorbers in the UVA and UVB region of spectra due to wide bandgap. Impact of zinc oxide on biological functions depends on its morphology, particle size, exposure time, concentration, pH, and biocompatibility. They are more effective against microorganisms such as Bacillus subtilis, Bacillus megaterium, Staphylococcus aureus, Sarcina lutea, Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumonia, Pseudomonas vulgaris, Candida albicans, and Aspergillus niger. Mechanism of action has been ascribed to the activation of zinc oxide nanoparticles by light, which penetrate the bacterial cell wall via diffusion. It has been confirmed from SEM and TEM images of the bacterial cells that zinc oxide nanoparticles disintegrate the cell membrane and accumulate in the cytoplasm where they interact with biomolecules causing cell apoptosis leading to cell death.

Experimental investigation on photoelectric properties of ZAO thin film deposited on flexible substrate by magnetron sputtering

NASA Astrophysics Data System (ADS)

Hao, Ming; Liu, Kun; Liu, Xinghua; Wang, Dongyang; Ba, Dechun; Xie, Yuanhua; Du, Guangyu; Ba, Yaoshuai

2016-12-01

Transparent conductive ZAO (Zinc Aluminum Oxide) films on flexible substrates have a great potential for low-cost mass-production solar cells. ZAO thin films were achieved on flexible PET (polyethylene terephthalate) substrates by RF magnetron sputtering technology. The surface morphology and element content, the transmittance and the sheet resistance of the films were measured to determine the optical process parameters. The results show that the ZAO thin film shows the best parameters in terms of photoelectric performance including sputtering power, working pressure, sputtering time, substrate temperature (100 W, 1.5 Pa, 60 min, 125 °C). The sheet resistance of 510 Ω and transmittance in visible region of 92% were obtained after characterization. Surface morphology was uniform and compact with a good crystal grain.

Lead zirconate titanate-nickel zink ferrite thick-film composites: obtaining by the screen printing technique and magnetoelectric properties

NASA Astrophysics Data System (ADS)

Bush, A. A.; Shkuratov, V. Ya.; Chernykh, I. A.; Fetisov, Y. K.

2010-03-01

Layered thick-film composites containing one lead zirconate titanate (PZT) layer, one nickel zinc ferrite (NZF) layer, two PZT-NZF layers, or three PZT-NZF-PZT layers each 40-50 μm thick are prepared. The layers are applied by screen printing on a ceramic aluminum oxide substrate with a preformed contact (conducting) layer. The dielectric properties of the composites are studied in the temperature interval 80-900 K and the frequency interval 25 Hz-1 MHz. Polarized samples exhibit piezoelectric, pyroelectric, and magnetoelectric effects. In tangentially magnetized two- and three-layer composites, the magnetoelectric conversion factor equals 57 kV/(m T) at low frequencies and reaches 2000 kV/(m T) at the mechanical resonance frequency.

Low oxidation state aluminum-containing cluster anions: Cp{sup ∗}Al{sub n}H{sup −}, n = 1–3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Xinxing; Ganteför, Gerd; Bowen, Kit, E-mail: AKandalam@wcupa.edu, E-mail: kbowen@jhu.edu

Three new, low oxidation state, aluminum-containing cluster anions, Cp*Al{sub n}H{sup −}, n = 1–3, were prepared via reactions between aluminum hydride cluster anions, Al{sub n}H{sub m}{sup −}, and Cp*H ligands. These were characterized by mass spectrometry, anion photoelectron spectroscopy, and density functional theory based calculations. Agreement between the experimentally and theoretically determined vertical detachment energies and adiabatic detachment energies validated the computed geometrical structures. Reactions between aluminum hydride cluster anions and ligands provide a new avenue for discovering low oxidation state, ligated aluminum clusters.

REMOVAL OF RADIOACTIVE IONS FROM WATERS

DOEpatents

Silker, W.B.

1962-04-10

A process for removing neutron-reaction products, such as phosphorus, arsenic, manganese, copper, zinc, lanthanides, and actinides, from aqueous solutions by sorption on particles of aluminum metal is described. (AEC)

Microwave Synthesis of Zinc Hydroxy Sulfate Nanoplates and Zinc Oxide Nanorods in the Classroom

ERIC Educational Resources Information Center

Dziedzic, Rafal M.; Gillian-Daniel, Anne Lynn; Peterson, Greta M.; Martínez-Herna´ndez, Kermin J.

2014-01-01

In this hands-on, inquiry-based lab, high school and undergraduate students learn about nanotechnology by synthesizing their own nanoparticles in a single class period. This simple synthesis of zinc oxide nanorods and zinc hydroxy sulfate nanoplates can be done in 15 min using a household microwave oven. Reagent concentration, reaction…

The effect of surface oxide layer on the rate of hydrogen emission from aluminum and its alloys in a high vacuum

NASA Technical Reports Server (NTRS)

Makarova, V. I.; Zyabrev, A. A.

1979-01-01

The influence of surface oxide layers on the kinetics of hydrogen emission at the high vacuum of 10 to the minus 8th power torr was investigated at temperatures from 20 to 450 C using samples of pure AB00 aluminum and the cast alloy AMg. Cast and deformed samples of AMts alloy were used to study the effect of oxide film thickness on the rate of hydrogen emission. Thermodynamic calculations of the reactions of the generation and dissociation of aluminum oxide show that degasification at elevated temperatures (up to 600 C) and high vacuum will not reduce the thickness of artificially-generated surface oxide layers on aluminum and its alloys.

Photoemission study of tris(8-hydroxyquinoline) aluminum/aluminum oxide/tris(8-hydroxyquinoline) aluminum interface

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ding Huanjun; Zorba, Serkan; Gao Yongli

2006-12-01

The evolution of the interface electronic structure of a sandwich structure involving aluminum oxide and tris(8-hydroxyquinoline) aluminum (Alq), i.e. (Alq/AlO{sub x}/Alq), has been investigated with photoemission spectroscopy. Strong chemical reactions have been observed due to aluminum deposition onto the Alq substrate. The subsequent oxygen exposure releases some of the Alq molecules from the interaction with aluminum. Finally, the deposition of the top Alq layer leads to an asymmetry in the electronic energy level alignment with respect to the AlO{sub x} interlayer.

Rambutan peels promoted biomimetic synthesis of bioinspired zinc oxide nanochains for biomedical applications

NASA Astrophysics Data System (ADS)

Yuvakkumar, R.; Suresh, J.; Saravanakumar, B.; Joseph Nathanael, A.; Hong, Sun Ig; Rajendran, V.

2015-02-01

A naturally occurring rambutan peel waste was employed to synthesis bioinspired zinc oxide nanochains. Rambutan peels has the ability of ligating zinc ions as a natural ligation agent resulting in zinc oxide nanochains formation due to its extended polyphenolic system over incubation period. Successful formation of zinc oxide nanochains was confirmed employing transmission electron microscopy studies. About 60% and ∼40% cell viability was lost and 50% and 10% morphological change was observed in 7 and 4 days incubated ZnO treated cells compared with control. Moreover, 50% and 55% of cell death was observed at 24 and 48 h incubation with 7 days treated ZnO cells and hence alters and disturbs the growth of cancer cells and could be used for liver cancer cell treatment.

Atomic-Scale Insights into the Oxidation of Aluminum

DOE PAGES

Nguyen, Lan; Hashimoto, Teruo; Zakharov, Dmitri N.; ...

2018-01-10

Here, the surface oxidation of aluminum is still poorly understood despite its vital role as an insulator in electronics, in aluminum–air batteries, and in protecting the metal against corrosion. Here we use atomic resolution imaging in an environmental transmission electron microscope (TEM) to investigate the mechanism of aluminum oxide formation. Harnessing electron beam sputtering we prepare a pristine, oxide-free metal surface in the TEM. This allows us to study, as a function of crystallographic orientation and oxygen gas pressure, the full oxide growth regime from the first oxide nucleation to a complete anometers-thick surface film.

Investigation of ZnO Nanowire Interfaces for Multi-Scale Composites

DTIC Science & Technology

2012-03-06

growth of zinc oxide ( ZnO ) nanowires on the surface of the...through the growth of zinc oxide ( ZnO ) nanowires on the surface of the reinforcing fibers. The nanowires functionally grade the interface, improve bonding...bulk composite. This has been accomplished through the growth of zinc oxide ( ZnO ) nanowires on the surface of the reinforcing fibers. ZnO

Anticancer activity of fungal L-asparaginase conjugated with zinc oxide nanoparticles.

PubMed

Baskar, G; Chandhuru, J; Sheraz Fahad, K; Praveen, A S; Chamundeeswari, M; Muthukumar, T

2015-01-01

Demand for developing novel delivery system for cancer treatment has increased due to the side effects present in intravenous injection of L-asparaginase. Nanoparticles are used for delivering the drugs to its destination in cancer cure. Nanobiocomposite of zinc oxide nanoparticles conjugated with L-asparaginase was produced by Aspergillus terreus and was confirmed using maximum UV-Vis absorption at 340 nm in the present work. The presence of functional groups like OH, C-H, -C=N and C=O on the surface of nanobiocomposite was found from Fourier transform infrared spectrum analysis. Size of the produced nanocomposite was found in the range of 28-63 nm using scanning electron microscope. The crystalline nature of the synthesized nanobiocomposites was confirmed by X-ray diffraction analysis. The presence of zinc oxide on synthesized nanobiocomposite was confirmed by energy dispersive spectrum analysis. The anti-cancerous nature of the synthesized zinc oxide conjugated L-asparaginase nanobiocomposite on MCF-7 cell line was studied using MTT assay. The viability of the MCF-7 cells was decreased to 35.02 % when it was treated with L-asparaginase conjugated zinc oxide nanobiocomposite. Hence it is proved that the synthesized nanobiocomposites of zinc oxide conjugated L-asparaginase has good anti-cancerous activity.

Crystal Structure Characterization of Thin Layer Zinc Oxide

NASA Astrophysics Data System (ADS)

Doyan, Aris; Susilawati; Azizatul Fitri, Siti; Ahzan, Sukainil

2017-05-01

In this research the characterization of the crystal structure of a thin layer of ZnO (zinc oxide) were synthesized by sol - gel method and spin coating deposited on a glass substrate. The samples were divided into three sol concentrations of 0.1, 0.3, 0.5 Molar and two deposition temperature is 350 °C, and 550 °C. UV-Vis. spectrophotometer results showed that in the spectrum of visible light (wavelength range 300-800 nm) has a transmittance value of which increases with increasing concentration and temperature deposition of zinc oxide, otherwise the value of the absorption and the band gap energy decreases with the addition of concentration and deposition temperature. The transmittances value of the highest and lowest absorption was 93.5% and 0.03 is at a concentration of 0.1 M and zinc oxide deposition temperature of 550 °C, with a value of band gap energy of 2.98 eV. The XRD results showed that the zinc oxide crystal orientation in the field of 013 with a crystal grain size 14.4472 nm. SEM results showed the surface morphology of zinc oxide such as rod-like.

Targeted Zinc Delivery: A Novel Treatment for Prostate Cancer

DTIC Science & Technology

2010-06-01

aconitase, which normally functions to oxidize citrate during the Krebs cycle . Because citrate is a principle component of seminal fluid, prostate...tissue, likely due to the metabolic effects of zinc in the Krebs cycle . That is, because zinc inhibits m- aconitase, loss of zinc allows for greater...secretory cells do not complete the oxidation of citrate in the mitochondria and the zinc-mediated inhibition of m-aconitase is crucial for the

Adsorption of poly(vinyl formamide-co-vinyl amine) (PVFA-co-PVAm) polymers on zinc, zinc oxide, iron, and iron oxide surfaces.

PubMed

Seifert, Susan; Simon, Frank; Baumann, Giesela; Hietschold, Michael; Seifert, Andreas; Spange, Stefan

2011-12-06

The adsorption of poly(vinyl formamide) (PVFA) and the statistic copolymers poly(vinyl formamide-co-vinyl amine) (PVFA-co-PVAm) onto zinc and iron metal particles as well as their oxides was investigated. The adsorbates were characterized by means of XPS, DRIFT spectroscopy, wet chemical analysis, and solvatochromic probes. Dicyano-bis-(1,10-phenanthroline)-iron(II) (1), 3-(4-amino-3-methylphenyl)-7-phenyl-benzo-[1,2-b:4,5-b']difuran-2,6-dione (2), and 4-tert-butyl-2-(dicyano-methylene)-5-[4-(diethylamino)-benzylidene]-Δ(3)-thiazoline (3) as solvatochromic probes were coadsorbed onto zinc oxide to measure various effects of surface polarity. The experimental findings showed that the adsorption mechanism of PVFA and PVFA-co-PVAm strongly depends on the degree of hydrolysis of PVFA and pH values and also on the kind of metal or metal oxide surfaces that were employed as adsorbents. The adsorption mechanism of PVFA/PVFA-co-PVAm onto zinc oxide and iron oxide surfaces is mainly affected by electrostatic interactions. Particularly in the region of pH 5, the adsorption of PVFA/PVFA-co-PVAm onto zinc and iron metal particles is additionally influenced by redox processes, dissolution, and complexation reactions. © 2011 American Chemical Society

Addressing the Limit of Detectability of Residual Oxide Discontinuities in Friction Stir Butt Welds of Aluminum using Phased Array Ultrasound

NASA Technical Reports Server (NTRS)

Johnston, P. H.

2008-01-01

This activity seeks to estimate a theoretical upper bound of detectability for a layer of oxide embedded in a friction stir weld in aluminum. The oxide is theoretically modeled as an ideal planar layer of aluminum oxide, oriented normal to an interrogating ultrasound beam. Experimentally-measured grain scattering level is used to represent the practical noise floor. Echoes from naturally-occurring oxides will necessarily fall below this theoretical limit, and must be above the measurement noise to be potentially detectable.

Assessment of methane production from shredder waste in landfills: The influence of temperature, moisture and metals.

PubMed

Fathi Aghdam, Ehsan; Scheutz, Charlotte; Kjeldsen, Peter

2017-05-01

In this study, methane (CH 4 ) production rates from shredder waste (SW) were determined by incubation of waste samples over a period of 230days under different operating conditions, and first-order decay kinetic constants (k-values) were calculated. SW and sterilized SW were incubated under different temperatures (20-25°C, 37°C, and 55°C), moisture contents (35% and 75% w/w) and amounts of inoculum (5% and 30% of the samples wet weight). The biochemical methane potential (BMP) from different types of SW (fresh, old and sieved) was determined and compared. The ability of metals (iron, aluminum, zinc, and copper) contained in SW to provide electrons for methanogens resulting in gas compositions with high CH 4 contents and very low CO 2 contents was investigated. The BMP of SW was 1.5-6.2kg CH 4 /ton waste. The highest BMP was observed in fresh SW samples, while the lowest was observed in sieved samples (fine fraction of SW). Abiotic production of CH 4 was not observed in laboratory incubations. The biotic experiments showed that when the moisture content was 35% w/w and the temperature was 20-25°C, CH 4 production was extremely low. Increasing the temperature from 20-25°C to 37°C resulted in significantly higher CH 4 production while increasing the temperature from 37°C to 55°C resulted in higher CH 4 production, but to a lower extent. Increasing the moisture and inoculum content also increased CH 4 production. The k-values were 0.033-0.075yr -1 at room temperature, 0.220-0.429yr -1 at 37°C and 0.235-0.488yr -1 at 55°C, indicating that higher temperatures resulted in higher k-values. It was observed that H 2 can be produced by biocorrosion of iron, aluminum, and zinc and it was shown that produced H 2 can be utilized by hydrogenotrophic methanogens to convert CO 2 to CH 4 . Addition of iron and copper to SW resulted in inhibition of CH 4 production, while addition of aluminum and zinc resulted in higher CH 4 production. This suggested that aluminum and zinc contribute to high CH 4 production from SW by providing H 2 for hydrogenotrophic methanogens. Gas compositions with higher CH 4 and lower CO 2 observed in landfilled SW are thus most likely due to the consumption of existing CO 2 in the produced biogas and the produced H 2 by biocorrosion of aluminum and zinc by methanogens. Copyright © 2016 Elsevier Ltd. All rights reserved.

Experimental Investigation of Performance and emission characteristics of Various Nano Particles with Bio-Diesel blend on Di Diesel Engine

NASA Astrophysics Data System (ADS)

Karthik, N.; Goldwin Xavier, X.; Rajasekar, R.; Ganesh Bairavan, P.; Dhanseelan, S.

2017-05-01

Present study provides the effect of Zinc Oxide (ZnO) and Cerium Oxide (CeO2) nanoparticles additives on the Performance and emission uniqueness of Jatropha. Jatropha blended fuel is prepared by the emulsification technique with assist of mechanical agitator. Nano particles (Zinc Oxide (ZnO)) and Cerium Oxide (CeO2)) mixed with Jatropha blended fuel in mass fraction (100 ppm) with assist of an ultrasonicator. Experiments were conducted in single cylinder constant speed direct injection diesel engine for various test fuels. Performance results revealed that Brake Thermal Efficiency (BTE) of Jatropha blended Cerium Oxide (B20CE) is 3% and 11% higher than Jatropha blended zinc oxide (B20ZO) and Jatropha blended fuel (B20) and 4% lower than diesel fuel (D100) at full load conditions. Emission result shows that HC and CO emissions of Jatropha blended Cerium Oxide (B20CE) are (6%, 22%, 11% and 6%, 15%, 12%) less compared with Jatropha blended Zinc Oxide (B20ZO), diesel (D100) and Jatropha blended fuel (B20) at full load conditions. NOx emissions of Jatropha blended Cerium Oxide is 1 % higher than diesel fuel (D100) and 2% and 5% lower than Jatropha blended Zinc Oxide, and jatropha blended fuel.

Mild zinc deficiency in male and female rats: early postnatal alterations in renal nitric oxide system and morphology.

PubMed

Tomat, Analia Lorena; Veiras, Luciana Cecilia; Aguirre, Sofía; Fasoli, Héctor; Elesgaray, Rosana; Caniffi, Carolina; Costa, María Ángeles; Arranz, Cristina Teresa

2013-03-01

Fetal and postnatal zinc deficiencies induce an increase in arterial blood pressure and impair renal function in male adult rats. We therefore hypothesized that these renal alterations are present in early stages of life and that there are sexual differences in the adaptations to this nutritional injury. The aim was to study the effects of moderate zinc deficiency during fetal life and lactation on renal morphology, oxidative stress, apoptosis, and the nitric oxide system in male and female rats at 21 d of life. Female Wistar rats received low (8 ppm) or control (30 ppm) zinc diets from the beginning of pregnancy to weaning. Glomerulus number, morphology, oxidative stress, apoptotic cells, nitric oxide synthase activity, and protein expression were evaluated in the kidneys of offspring at 21 d. Zinc deficiency decreased the nephron number, induced glomerular hypertrophy, increased oxidative damage, and decreased nitric oxide synthase activity in the male and female rat kidneys. Nitric oxide synthase activity was not affected by inhibitors of the neuronal or inducible isoforms, so nitric oxide was mainly generated by the endothelial isoenzyme. Gender differences were observed in glomerular areas and antioxidant enzyme activities. Zinc deficiency during fetal life and lactation induces an early decrease in renal functional units, associated with a decrease in nitric oxide activity and an increase in oxidative stress, which would contribute to increased arterial blood pressure and renal dysfunction in adulthood. The sexual differences observed in this model may explain the dissimilar development of hypertension and renal diseases in adult life. Copyright © 2013 Elsevier Inc. All rights reserved.

JACKETED FUEL ELEMENT

DOEpatents

Wigner, E.P.; Szilard, L.; Creutz, E.C.

1959-02-01

These fuel elements are comprised of a homogeneous metallic uranium body completely enclosed and sealed in an aluminum cover. The uranium body and aluminum cover are bonded together by a layer of zinc located between them. The bonding layer serves to improve transfer of heat, provides an additional protection against corrosion of the uranium by the coolant, and also localizes any possible corrosion by preventing travel of corrosive material along the surface of the fuel element.

Wastewater Characterization Survey, Edwards Air Force Base, California

DTIC Science & Technology

1992-08-01

sampling, 23 and 24 Feb 92, concentrations of aluminum, chromium , copper, and iron were found to be slightly elevated when compared to average...concentrations of these metals detected during the other 6 sampling days. Detectable concentrations of aluminum, chromium , and zinc could be the result of...35.00 Cyanide .......................... 30.00 23.00 49.00 Chemical Oxygen Demand ........ 25.00 13.00 40.00 Chromium VI ...................... 25.00

Trace elements in sera from patients with renal disease

NASA Astrophysics Data System (ADS)

Miura, Yoshinori; Nakai, Keiko; Sera, Kouichiro; Sato, Michirou

1999-04-01

In hemodialysis (HD) patients, an accumulation of trace elements such as aluminum, copper, silicon and vanadium has been reported. Aluminum-caused encephalopathy and aluminum-related bone diseases are important trace element-related complications. Using particle induced X-ray emission (PIXE) we determined concentrations of aluminum, silicon, copper, zinc, selenium and bromine in sera of 29 patients with HD, 14 nondialysis patients with renal disease (RD) and 27 normal controls. The concentration of serum silicon of the patients with HD was 107.4 ± 61.3 μmol/l, which is markedly higher than that of normal controls (48.3 ± 25.8 μmol/l, p < 0.0001). The serum concentrations of zinc and bromine in patients with HD were 11.9 ± 1.7 and 21.3 ± 3.0 μmol/l, respectively. Both were markedly lower than those of normal controls (15.6 ± 2.6, 69.2 ± 8.3 μmol/l, p < 0.0001). The concentrations of aluminium and bromine in the serum of patients with RD were 171.9 ± 64.3 and 81.9 ± 11.6 μmol/l, which were markedly higher than those of normal controls ( p < 0.0001, p < 0.001). No significant differences were observed in the concentration of copper and selenium among three groups.

Spectroscopic characterization of zinc oxide nanorods synthesized by solid-state reaction

NASA Astrophysics Data System (ADS)

Prasad, Virendra; D'Souza, Charlene; Yadav, Deepti; Shaikh, A. J.; Vigneshwaran, Nadanathangam

2006-09-01

Well-crystallized zinc oxide nanorods have been fabricated by single step solid-state reaction using zinc acetate and sodium hydroxide, at room temperature. The sodium lauryl sulfate (SLS) stabilized zinc oxide nanorods were characterized by using X-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy and photoluminescence spectroscopy. The X-ray diffraction revealed the wurtzite structure of zinc oxide. The size estimation by XRD and TEM confirmed that the ZnO nanorods are made of single crystals. The growth of zinc oxide crystals into rod shape was found to be closely related to its hexagonal nature. The mass ratio of SLS:ZnO in the nanorods was found to be 1:10 based on the thermogravimetric analysis. Blue shift of photoluminescence emission was noticed in the ZnO nanorods when compared to that of ZnO bulk. FT-IR analysis confirmed the binding of SLS with ZnO nanorods. Apart from ease of preparation, this method has the advantage of eco-friendliness since the solvent and other harmful chemicals were eliminated in the synthesis protocol.

Zinc protects HepG2 cells against the oxidative damage and DNA damage induced by ochratoxin A

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zheng, Juanjuan; Zhang, Yu; Xu, Wentao, E-mail: xuwentaoboy@sina.com

Oxidative stress and DNA damage are the most studied mechanisms by which ochratoxin A (OTA) induces its toxic effects, which include nephrotoxicity, hepatotoxicity, immunotoxicity and genotoxicity. Zinc, which is an essential trace element, is considered a potential antioxidant. The aim of this paper was to investigate whether zinc supplement could inhibit OTA-induced oxidative damage and DNA damage in HepG2 cells and the mechanism of inhibition. The results indicated that that exposure of OTA decreased the intracellular zinc concentration; zinc supplement significantly reduced the OTA-induced production of reactive oxygen species (ROS) and decrease in superoxide dismutase (SOD) activity but did notmore » affect the OTA-induced decrease in the mitochondrial membrane potential (Δψ{sub m}). Meanwhile, the addition of the zinc chelator N,N,N′,N′-tetrakis(2-pyridylmethyl)ethylenediamine (TPEN) strongly aggravated the OTA-induced oxidative damage. This study also demonstrated that zinc helped to maintain the integrity of DNA through the reduction of OTA-induced DNA strand breaks, 8-hydroxy-2′-deoxyguanosine (8-OHdG) formation and DNA hypomethylation. OTA increased the mRNA expression of metallothionein1-A (MT1A), metallothionein2-A (MT2A) and Cu/Zn superoxide dismutase (SOD1). Zinc supplement further enhanced the mRNA expression of MT1A and MT2A, but it had no effect on the mRNA expression of SOD1 and catalase (CAT). Zinc was for the first time proven to reduce the cytotoxicity of OTA through inhibiting the oxidative damage and DNA damage, and regulating the expression of zinc-associated genes. Thus, the addition of zinc can potentially be used to reduce the OTA toxicity of contaminated feeds. - Highlights: ► OTA decreased the intracellular zinc concentration. ► OTA induced the formation of 8-OHdG in HepG2 cells. ► It was testified for the first time that OTA induced DNA hypomethylation. ► Zinc protects against the oxidative damage and DNA damage induced by OTA in vitro.« less

Water Quality Conditions in the Missouri River Mainstem System: 2008 Report

DTIC Science & Technology

2009-09-01

aluminum, arsenic, cadmium , chromium, copper, cyanide, lead, nickel, selenium, silver, and zinc . The acute and chronic water quality standards criteria for... adipose , etc.) tend to accumulate toxicants at different rates. Therefore, when used as an indicator, fish tissue analysis typically uses whole...for metals (i.e., cadmium , chromium, copper, lead, nickel, silver, and zinc ) are based on hardness. Criteria shown for those metals were calculated

Modern steels for light automobiles (review)

NASA Astrophysics Data System (ADS)

Tikhonov, A. K.

1994-10-01

The article considers the directions of work at VAZ together with metallurgists of the CIS for creating highly efficient economically-alloyed and microalloyed steels; highly ductile forged steels with improved corrosion resistance coated with zinc and with good stamping, welding, and painting capacity. Steels are created for petrol tanks with aluminum-zinc coatings instead of lead, and new heat and corrosion-resistant steels are developed for automobile exhaust gas systems.

Oxidation resistant, thoria-dispersed nickel-chromium-aluminum alloy

NASA Technical Reports Server (NTRS)

Baranow, S.; Klingler, L. J.

1973-01-01

Modified thoria-dispersed nickel-chromium alloy has been developed that exhibits greatly improved resistance to high-temperature oxidation. Additions of aluminum have been made to change nature of protective oxide scale entirely and to essentially inhibit oxidation at temperatures up to 1260 C.

Effects of aluminum and extremely low frequency electromagnetic radiation on oxidative stress and memory in brain of mice.

PubMed

Deng, Yuanxin; Zhang, Yanwen; Jia, Shujie; Liu, Junkang; Liu, Yanxia; Xu, Weiwei; Liu, Lei

2013-12-01

This study was aimed to investigate the effect of aluminum and extremely low-frequency magnetic fields (ELF-MF) on oxidative stress and memory of SPF Kunming mice. Sixty male SPF Kunming mice were divided randomly into four groups: control group, ELF-MF group (2 mT, 4 h/day), load aluminum group (200 mg aluminum/kg, 0.1 ml/10 g), and ELF-MF + aluminum group (2 mT, 4 h/day, 200 mg aluminum/kg). After 8 weeks of treatment, the mice of three experiment groups (ELF-MF group, load aluminum group, and ELF-MF + aluminum group) exhibited firstly the learning memory impairment, appearing that the escaping latency to the platform was prolonged and percentage in the platform quadrant was reduced in the Morris water maze (MWM) task. Secondly are the pathologic abnormalities including neuronal cell loss and overexpression of phosphorylated tau protein in the hippocampus and cerebral cortex. On the other hand, the markers of oxidative stress were determined in mice brain and serum. The results showed a statistically significant decrease in superoxide dismutase activity and increase in the levels of malondialdehyde in the ELF-MF group (P < 0.05 or P < 0.01), load aluminum group (P < 0.01), and ELF-MF + aluminum group (P < 0.01). However, the treatment with ELF-MF + aluminum induced no more damage than ELF-MF and aluminum did, respectively. In conclusion, both aluminum and ELF-MF could impact on learning memory and pro-oxidative function in Kunming mice. However, there was no evidence of any association between ELF-MF exposure with aluminum loading.

Method of fabricating a catalytic structure

DOEpatents

Rollins, Harry W [Idaho Falls, ID; Petkovic, Lucia M [Idaho Falls, ID; Ginosar, Daniel M [Idaho Falls, ID

2009-09-22

A precursor to a catalytic structure comprising zinc oxide and copper oxide. The zinc oxide has a sheet-like morphology or a spherical morphology and the copper oxide comprises particles of copper oxide. The copper oxide is reduced to copper, producing the catalytic structure. The catalytic structure is fabricated by a hydrothermal process. A reaction mixture comprising a zinc salt, a copper salt, a hydroxyl ion source, and a structure-directing agent is formed. The reaction mixture is heated under confined volume conditions to produce the precursor. The copper oxide in the precursor is reduced to copper. A method of hydrogenating a carbon oxide using the catalytic structure is also disclosed, as is a system that includes the catalytic structure.

A zinc finger transcription factor ART1 regulates multiple genes implicated in aluminum tolerance in rice.

PubMed

Yamaji, Naoki; Huang, Chao Feng; Nagao, Sakiko; Yano, Masahiro; Sato, Yutaka; Nagamura, Yoshiaki; Ma, Jian Feng

2009-10-01

Aluminum (Al) toxicity is the major limiting factor of crop production on acid soils, but some plant species have evolved ways of detoxifying Al. Here, we report a C2H2-type zinc finger transcription factor ART1 (for Al resistance transcription factor 1), which specifically regulates the expression of genes related to Al tolerance in rice (Oryza sativa). ART1 is constitutively expressed in the root, and the expression level is not affected by Al treatment. ART1 is localized in the nucleus of all root cells. A yeast one-hybrid assay showed that ART1 has a transcriptional activation potential and interacts with the promoter region of STAR1, an important factor in rice Al tolerance. Microarray analysis revealed 31 downstream transcripts regulated by ART1, including STAR1 and 2 and a couple of homologs of Al tolerance genes in other plants. Some of these genes were implicated in both internal and external detoxification of Al at different cellular levels. Our findings shed light on comprehensively understanding how plants detoxify aluminum to survive in an acidic environment.

Cathodic Protection Deployment on Space Shuttle Solid Rocket Boosters

NASA Technical Reports Server (NTRS)

Zook, Lee M.

1998-01-01

Corrosion protection of the space shuttle solid rocket boosters incorporates the use of cathodic protection(anodes) in concert with several coatings systems. The SRB design has large carbon/carbon composites(motor nozzle) electrically connected to an aluminum alloy structure. Early in the STS program, the aluminum structures incurred tremendous corrosive attack due primarily to the galvanic couple to the carbon/carbon nozzle at coating damage locations. Also contributing to the galvanic corrosion problem were stainless steel and titanium alloy components housed within the aluminum structures and electrically connected to the aluminum structures. This paper will highlight the evolution in the protection of the aluminum structures, providing historical information and summary data from the operation of the corrosion protection systems. Also, data and information will be included regarding the evaluation and deployment of inorganic zinc rich primers as anode area on the aluminum structures.

Sorption behavior of microamounts of zinc on titanium oxide from aqueous solutions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hasany, S.M.; Ghaffar, A.; Chughtai, F.A.

1991-08-01

To correlate soil response toward zinc, it is necessary to study its adsorption in detail on soils or on their constituents. The adsorption of microamounts of zinc on titanium oxide, prepared and characterized in this laboratory, has been studied in detail. Zinc adsorption has been found to be dependent on the pH of the aqueous solution, amount of oxide, and zinc concentration. Maximum adsorption is from pH 10 buffer. EDTA and cyanide ions inhibit adsorption significantly. The adsorption of other elements under optimal conditions has also been measured on this oxide. Sc(III) and Cs(I) show almost negligible adsorption. Zinc adsorptionmore » follows the linear form of the Freundlich adsorption isotherm: log C{sub Ads} = log A + (1/n) log C{sub Bulk} with A = 0.48 mol/g and n = 1. Except at a very low bulk concentration (3 {times} 10{sup {minus}5} mol/dm{sup 3}), Langmuir adsorption isotherm is also linear for the entire zinc concentration investigated. The limiting adsorbed concentration is estimated to be 0.18 mol/g.« less

Sulfur dioxide leaching of spent zinc-carbon-battery scrap

NASA Astrophysics Data System (ADS)

Avraamides, J.; Senanayake, G.; Clegg, R.

Zinc-carbon batteries, which contain around 20% zinc, 35% manganese oxides and 10% steel, are currently disposed after use as land fill or reprocessed to recover metals or oxides. Crushed material is subjected to magnetic separation followed by hydrometallurgical treatment of the non-magnetic material to recover zinc metal and manganese oxides. The leaching with 2 M sulfuric acid in the presence of hydrogen peroxide recovers 93% Zn and 82% Mn at 25 °C. Alkaline leaching with 6 M NaOH recovers 80% zinc. The present study shows that over 90% zinc and manganese can be leached in 20-30 min at 30 °C using 0.1-1.0 M sulfuric acid in the presence of sulfur dioxide. The iron extraction is sensitive to both acid concentration and sulfur dioxide flow rate. The effect of reagent concentration and particle size on the extraction of zinc, manganese and iron are reported. It is shown that the iron and manganese leaching follow a shrinking core kinetic model due to the formation of insoluble metal salts/oxides on the solid surface. This is supported by (i) the decrease in iron and manganese extraction from synthetic Fe(III)-Mn(IV)-Zn(II) oxide mixtures with increase in acid concentration from 1 M to 2 M, and (ii) the low iron dissolution and re-precipitation of dissolved manganese and zinc during prolonged leaching of battery scrap with low sulfur dioxide.

Ultrafast dynamics of Al-doped zinc oxide under optical excitation (Presentation Recording)

NASA Astrophysics Data System (ADS)

Kinsey, Nathaniel; DeVault, Clayton T.; Kim, Jongbum; Ferrera, Marcello; Kildishev, Alexander V.; Shalaev, Vladimir M.; Boltasseva, Alexandra

2015-09-01

There is a continual need to explore new and promising dynamic materials to power next-generation switchable devices. In recent years, transparent conducting oxides have been shown to be vital materials for such systems, allowing for both optical and electrical tunability. Using a pump-probe technique, we investigate the optical tunability of CMOS-compatible, highly aluminum doped zinc oxide (AZO) thin films. The sample was pumped at 325 nm and probed with a weak beam at 1.3 μm to determine the timescale and magnitude of the changes by altering the temporal delay between the pulses with a delay line. For an incident fluence of 3.9 mJ/cm2 a change of 40% in reflection and 30% (max 6.3dB/μm modulation depth) in transmission is observed which is fully recovered within 1ps. Using a computational model, the experimental results were fitted for the given fluence allowing the recombination time and induced carrier density to be extracted. For a fluence of 3.9 mJ/cm2 the average excess carrier density within the material is 0.7×10^20cm-3 and the recombination time is 88fs. The ultrafast temporal response is the result of Auger recombination due to the extremely high carrier concentration present in our films, ~10^21 cm-3. By measuring and fitting the results at several incident fluence levels, the recombination time versus carrier density was determined and fitted with an Auger model resulting in an Auger coefficient of C = 1.03×10^20cm6/sec. Consequently, AZO is shown to be a unique, promising, and CMOS-compatible material for high performance dynamic devices in the near future.

Structural Transitions in Nanosized Zn0.97Al0.03O Powders under High Pressure Analyzed by in Situ Angle-Dispersive X-ray Diffraction

PubMed Central

Lin, Chih-Ming; Liu, Hsin-Tzu; Zhong, Shi-Yao; Hsu, Chia-Hung; Chiu, Yi-Te; Tai, Ming-Fong; Juang, Jenh-Yih; Chuang, Yu-Chun; Liao, Yen-Fa

2016-01-01

Nanosized aluminum-doped zinc oxide Zn1−xAlxO (AZO) powders (AZO-NPs) with x = 0.01, 0.03, 0.06, 0.09 and 0.11 were synthesized by chemical precipitation method. The thermogravimetric analysis (TGA) indicated that the precursors were converted to oxides from hydroxides near 250 °C, which were then heated to 500 °C for subsequent thermal processes to obtain preliminary powders. The obtained preliminary powders were then calcined at 500 °C for three hours. The structure and morphology of the products were measured and characterized by angle-dispersive X-ray diffraction (ADXRD) and scanning electron microscopy (SEM). ADXRD results showed that AZO-NPs with Al content less than 11% exhibited würtzite zinc oxide structure and there was no other impurity phase in the AZO-NPs, suggesting substitutional doping of Al on Zn sites. The Zn0.97Al0.03O powders (A3ZO-NPs) with grain size of about 21.4 nm were used for high-pressure measurements. The in situ ADXRD measurements revealed that, for loading run, the pressure-induced würtzite (B4)-to-rocksalt (B1) structural phase transition began at 9.0(1) GPa. Compared to the predicted phase-transition pressure of ~12.7 GPa for pristine ZnO nanocrystals of similar grain size (~21.4 nm), the transition pressure for the present A3ZO-NPs exhibited a reduction of ~3.7 GPa. The significant reduction in phase-transition pressure is attributed to the effects of highly selective site occupation, namely Zn2+ and Al3+, were mainly found in tetrahedral and octahedral sites, respectively. PMID:28773683

Subtractive Plasma-Assisted-Etch Process for Developing High Performance Nanocrystalline Zinc-Oxide Thin-Film-Transistors

DTIC Science & Technology

2015-03-26

THIN - FILM - TRANSISTORS THESIS Thomas M. Donigan, First Lieutenant, USAF AFIT-ENG-MS-15-M-027 DEPARTMENT OF THE AIR FORCE AIR UNIVERSITY AIR...DEVELOPING HIGH PERFORMANCE NANOCRYSTALLINE ZINC-OXIDE THIN - FILM - TRANSISTORS THESIS Presented to the Faculty Department of Electrical and...15-M-027 SUBTRACTIVE PLASMA-ASSISTED-ETCH PROCESS FOR DEVELOPING HIGH PERFORMANCE NANOCRYSTALLINE ZINC-OXIDE THIN - FILM - TRANSISTORS

Studies of Peptide-Mineral Interactions and Biosilicification

DTIC Science & Technology

2010-07-16

His). The effect of zinc oxide -binding peptides ( ZnO -BPs) on the morphology and formation of ZnO were studied using G-12 (GLHVMHKVAPPR) and EM-12...interactions with silica and zinc oxide . Detailed quantitative experimental studies together with molecular modeling studies have shown that G12 (GLHVMHKVAPPR...studies of a primitive 15. SUBJECT TERMS Peptides, zinc oxide , silica, silver, peptide-mineral interactions, computational chemistry, molecular

Thermodynamic Analysis for the Refining Ability of Salt Flux for Aluminum Recycling

PubMed Central

Hiraki, Takehito; Miki, Takahiro; Nakajima, Kenichi; Matsubae, Kazuyo; Nakamura, Shinichiro; Nagasaka, Tetsuya

2014-01-01

The removability of impurities during the aluminum remelting process by oxidation was previously investigated by our research group. In the present work, alternative impurity removal with chlorination has been evaluated by thermodynamic analysis. For 43 different elements, equilibrium distribution ratios among metal, chloride flux and oxide slag phases in the aluminum remelting process were calculated by assuming the binary systems of aluminum and an impurity element. It was found that the removability of impurities isn’t significantly affected by process parameters such as chloride partial pressure, temperature and flux composition. It was shown that Ho, Dy, Li, La, Mg, Gd, Ce, Yb, Ca and Sr can be potentially eliminated into flux by chlorination from the remelted aluminum. Chlorination and oxidation are not effective to remove other impurities from the melting aluminum, due to the limited parameters which can be controlled during the remelting process. It follows that a proper management of aluminum scrap such as sorting based on the composition of the products is important for sustainable aluminum recycling. PMID:28788144

In vitro assessment of the antimicrobial activity of silver and zinc oxide nanoparticles against fish pathogens.

PubMed

Shaalan, Mohamed Ibrahim; El-Mahdy, Magdy Mohamed; Theiner, Sarah; El-Matbouli, Mansour; Saleh, Mona

2017-07-21

Antibiotic resistance is a global issue that threatens public health. The excessive use of antibiotics contributes to this problem as the genes of antibiotic resistance can be transferred between the bacteria in humans, animals and aquatic organisms. Metallic nanoparticles could serve as future substitutes for some conventional antibiotics because of their antimicrobial activity. The aim of this study was to evaluate the antimicrobial effects of silver and zinc oxide nanoparticles against major fish pathogens and assess their safety in vitro. Silver nanoparticles were synthesized by chemical reduction and characterized with UV-Vis spectroscopy, transmission electron microscopy and zeta sizer. The concentrations of silver and zinc oxide nanoparticles were measured using inductively coupled plasma-mass spectrometry. Subsequently, silver and zinc oxide nanoparticles were tested for their antimicrobial activity against Aeromonas hydrophila, Aeromonas salmonicida subsp. salmonicida, Edwardsiella ictaluri, Edwardsiella tarda, Francisella noatunensis subsp. orientalis, Yersinia ruckeri and Aphanomyces invadans and the minimum inhibitory concentrations were determined. MTT assay was performed on eel kidney cell line (EK-1) to determine the cell viability after incubation with nanoparticles. The interaction between silver nanoparticles and A. salmonicida was investigated by transmission electron microscopy. The tested nanoparticles exhibited marked antimicrobial activity. Silver nanoparticles inhibited the growth of both A. salmonicida and A. invadans at a concentration of 17 µg/mL. Zinc oxide nanoparticles inhibited the growth of A. salmonicida, Y. ruckeri and A. invadans at concentrations of 15.75, 31.5 and 3.15 µg/mL respectively. Silver nanoparticles showed higher cell viability when compared to zinc oxide nanoparticles in the MTT assay. Transmission electron microscopy showed the attachment of silver nanoparticles to the bacterial membrane and disruption of its integrity. This is the first study on inhibitory effects of silver and zinc oxide nanoparticles towards A. salmonicida and A. invadans. Moreover, zinc oxide nanoparticles inhibited the growth of Y. ruckeri. In low concentrations, silver nanoparticles were less cytotoxic than zinc oxide nanoparticles and represent an alternative antimicrobial compound against A. hydrophila, A. salmonicida and A. invadans.

Efficacy assessment of acid mine drainage treatment with coal mining waste using Allium cepa L. as a bioindicator.

PubMed

Geremias, Reginaldo; Bortolotto, Tiago; Wilhelm-Filho, Danilo; Pedrosa, Rozangela Curi; de Fávere, Valfredo Tadeu

2012-05-01

The aim of this study was to evaluate the efficacy of the treatment of acid mine drainage (AMD) with calcinated coal mining waste using Allium cepa L. as a bioindicator. The pH values and the concentrations of aluminum, iron, manganese, zinc, copper, lead and sulfate were determined before and after the treatment of the AMD with calcinated coal mining waste. Allium cepa L. was exposed to untreated and treated AMD, as well as to mineral water as a negative control (NC). At the end of the exposure period, the inhibition of root growth was measured and the mean effective concentration (EC(50)) was determined. Oxidative stress biomarkers such as lipid peroxidation (TBARS), protein carbonyls (PC), catalase activity (CAT) and reduced glutathione levels (GSH) in the fleshy leaves of the bulb, as well as the DNA damage index (ID) in meristematic cells, were evaluated. The results indicated that the AMD treatment with calcinated coal mining waste resulted in an increase in the pH and an expressive removal of aluminum, iron, manganese and zinc. A high sub-chronic toxicity was observed when Allium cepa L. was exposed to the untreated AMD. However, after the treatment no toxicity was detected. Levels of TBARS and PC, CAT activity and the DNA damage index were significantly increased (P<0.05) in Allium cepa L. exposed to untreated AMD when compared to treated AMD and also to negative controls. No significant alteration in the GSH content was observed. In conclusion, the use of calcinated coal mining waste associated with toxicological tests on Allium cepa L. represents an alternative system for the treatment and biomonitoring of these types of environmental contaminants. Copyright © 2011 Elsevier Inc. All rights reserved.

Preparation of Aluminum Nanomesh Thin Films from an Anodic Aluminum Oxide Template as Transparent Conductive Electrodes

NASA Astrophysics Data System (ADS)

Li, Yiwen; Chen, Yulong; Qiu, Mingxia; Yu, Hongyu; Zhang, Xinhai; Sun, Xiao Wei; Chen, Rui

2016-02-01

We have employed anodic aluminum oxide as a template to prepare ultrathin, transparent, and conducting Al films with a unique nanomesh structure for transparent conductive electrodes. The anodic aluminum oxide template is obtained through direct anodization of a sputtered Al layer on a glass substrate, and subsequent wet etching creates the nanomesh metallic film. The optical and conductive properties are greatly influenced by experimental conditions. By tuning the anodizing time, transparent electrodes with appropriate optical transmittance and sheet resistance have been obtained. The results demonstrate that our proposed strategy can serve as a potential method to fabricate low-cost TCEs to replace conventional indium tin oxide materials.

Preparation of Aluminum Nanomesh Thin Films from an Anodic Aluminum Oxide Template as Transparent Conductive Electrodes

PubMed Central

Li, Yiwen; Chen, Yulong; Qiu, Mingxia; Yu, Hongyu; Zhang, Xinhai; Sun, Xiao Wei; Chen, Rui

2016-01-01

We have employed anodic aluminum oxide as a template to prepare ultrathin, transparent, and conducting Al films with a unique nanomesh structure for transparent conductive electrodes. The anodic aluminum oxide template is obtained through direct anodization of a sputtered Al layer on a glass substrate, and subsequent wet etching creates the nanomesh metallic film. The optical and conductive properties are greatly influenced by experimental conditions. By tuning the anodizing time, transparent electrodes with appropriate optical transmittance and sheet resistance have been obtained. The results demonstrate that our proposed strategy can serve as a potential method to fabricate low-cost TCEs to replace conventional indium tin oxide materials. PMID:26831759

Preparation of Aluminum Nanomesh Thin Films from an Anodic Aluminum Oxide Template as Transparent Conductive Electrodes.

PubMed

Li, Yiwen; Chen, Yulong; Qiu, Mingxia; Yu, Hongyu; Zhang, Xinhai; Sun, Xiao Wei; Chen, Rui

2016-02-02

We have employed anodic aluminum oxide as a template to prepare ultrathin, transparent, and conducting Al films with a unique nanomesh structure for transparent conductive electrodes. The anodic aluminum oxide template is obtained through direct anodization of a sputtered Al layer on a glass substrate, and subsequent wet etching creates the nanomesh metallic film. The optical and conductive properties are greatly influenced by experimental conditions. By tuning the anodizing time, transparent electrodes with appropriate optical transmittance and sheet resistance have been obtained. The results demonstrate that our proposed strategy can serve as a potential method to fabricate low-cost TCEs to replace conventional indium tin oxide materials.

Aluminum, iron, lead, cadmium, copper, zinc, chromium, magnesium, strontium, and calcium content in bone of end-stage renal failure patients.

PubMed

D'Haese, P C; Couttenye, M M; Lamberts, L V; Elseviers, M M; Goodman, W G; Schrooten, I; Cabrera, W E; De Broe, M E

1999-09-01

Little is known about trace metal alterations in the bones of dialysis patients or whether particular types of renal osteodystrophy are associated with either increased or decreased skeletal concentrations of trace elements. Because these patients are at risk for alterations of trace elements as well as for morbidity from skeletal disorders, we measured trace elements in bone of patients with end-stage renal disease. We analyzed bone biopsies of 100 end-stage renal failure patients enrolled in a hemodialysis program. The trace metal contents of bone biopsies with histological features of either osteomalacia, adynamic bone disease, mixed lesion, normal histology, or hyperparathyroidism were compared with each other and with the trace metal contents of bone of subjects with normal renal function. Trace metals were measured by atomic absorption spectrometry. The concentrations of aluminum, chromium, and cadmium were increased in bone of end-stage renal failure patients. Comparing the trace metal/calcium ratio, significantly higher values were found for the bone chromium/calcium, aluminum/calcium, zinc/calcium, magnesium/calcium, and strontium/calcium ratios. Among types of renal osteodystrophy, increased bone aluminum, lead, and strontium concentrations and strontium/calcium and aluminum/calcium ratios were found in dialysis patients with osteomalacia vs the other types of renal osteodystrophy considered as one group. Moreover, the concentrations of several trace elements in bone were significantly correlated with each other. Bone aluminum was correlated with the time on dialysis, whereas bone iron, aluminum, magnesium, and strontium tended to be associated with patient age. Bone trace metal concentrations did not depend on vitamin D intake nor on the patients' gender. The concentration of several trace elements in bone of end-stage renal failure patients is disturbed, and some of the trace metals under study might share pathways of absorption, distribution, and accumulation. The clinical significance of the increased/decreased concentrations of several trace elements other than aluminum in bone of dialysis patients deserves further investigation.

Effect of oxide layer formation on deformation of aluminum alloys under fire conditions

DOE PAGES

Yilmaz, Nadir; Vigil, Francisco M.; Tolendino, Greg; ...

2015-05-14

The purpose of this study is to investigate the structural behavior of aluminum alloys used in the aerospace industry when exposed to conditions similar to those of an accident scenario, such as a fuel fire. This study focuses on the role that the aluminum oxide layer plays in the deformation and the strength of the alloy above melting temperature. To replicate some of the thermal and atmospheric conditions that the alloys might experience in an accident scenario, aluminum rod specimens were subjected to temperatures near to or above their melting temperature in air, nitrogen, and vacuum environments. The characteristics ofmore » their deformation, such as geometry and rate of deformation, were observed. Tests were conducted by suspending aluminum rods vertically from an enclosure. This type of experiment was performed in two different environments: air and nitrogen. The change in environments allowed the effects of the oxide layer on the material strength to be analyzed by inhibiting the growth of the oxide layer. Observations were reported from imaging taken during the experiment showing creep behavior of aluminum alloys at elevated temperatures and time to failure. In addition, an example of tensile load–displacement data obtained in air and vacuum was reported to understand the effect of oxide layer on aluminum deformation and strength.« less

Metal | polypyrrole battery with the air regenerated positive electrode

NASA Astrophysics Data System (ADS)

Grgur, Branimir N.

2014-12-01

Recharge characteristics of the battery based on the electrochemically synthesized polypyrrole cathode and aluminum, zinc, or magnesium anode in 2 M NH4Cl are investigated. It is shown that polypyrrole electrode can be regenerated by the reoxidation with the dissolved oxygen from the air. Using the polypyrrole synthesized on high surface graphite-felt electrode under modest discharge conditions, stable discharge voltage of 1.1 V is obtained. Such behavior is explained by the complex interaction of polypyrrole and hydrogen peroxide produced by the oxygen reduction reaction. The electrochemical characteristics are compared with the zinc-manganese dioxide and zinc-air systems.

Rambutan peels promoted biomimetic synthesis of bioinspired zinc oxide nanochains for biomedical applications.

PubMed

Yuvakkumar, R; Suresh, J; Saravanakumar, B; Joseph Nathanael, A; Hong, Sun Ig; Rajendran, V

2015-02-25

A naturally occurring rambutan peel waste was employed to synthesis bioinspired zinc oxide nanochains. Rambutan peels has the ability of ligating zinc ions as a natural ligation agent resulting in zinc oxide nanochains formation due to its extended polyphenolic system over incubation period. Successful formation of zinc oxide nanochains was confirmed employing transmission electron microscopy studies. About 60% and ∼40% cell viability was lost and 50% and 10% morphological change was observed in 7 and 4 days incubated ZnO treated cells compared with control. Moreover, 50% and 55% of cell death was observed at 24 and 48 h incubation with 7 days treated ZnO cells and hence alters and disturbs the growth of cancer cells and could be used for liver cancer cell treatment. Copyright © 2014 Elsevier B.V. All rights reserved.

Methods for collection and analysis of geopressured geothermal and oil field waters

USGS Publications Warehouse

Lico, Michael S.; Kharaka, Yousif K.; Carothers, William W.; Wright, Victoria A.

1982-01-01

Present methods are described for the collection, preservation, and chemical analysis of waters produced from geopressured geothermal and petroleum wells. Detailed procedures for collection include precautions and equipment necessary to ensure that the sample is representative of the water produced. Procedures for sample preservation include filtration, acidification, dilution for silica, methyl isobutyl ketone (MIBK) extraction of aluminum, addition of potassium permanganate to preserve mercury, and precipitation of carbonate species as strontium carbonate for stable carbon isotopes and total dissolved carbonate analysis. Characteristics determined at the well site are sulfide, pH, ammonia, and conductivity. Laboratory procedures are given for the analysis of lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, iron, manganese, zinc, lead, aluminum, .and mercury by atomic absorption and flame emission spectroscopy. Chloride is determined by silver nitrate titration and fluoride by ion-specific electrode. Bromide and iodide concentrations are determined by the hypochlorite oxidation method. Sulfate is analyzed by titration using barium chloride with thorin indicator after pretreatment with alumina. Boron and silica are determined colorimetrically by the carmine and molybdate-blue methods, respectively. Aliphatic acid anions (C2 through C5) are determined by gas chromatography after separation and concentration in a chloroform-butanol mixture.

Oxidation and corrosion resistance of candidate Stirling engine heater-head-tube alloys

NASA Technical Reports Server (NTRS)

Stephens, J. R.; Barrett, C. A.

1984-01-01

Sixteen candidate iron base Stirling engine heater head tube alloys are evaluated in a diesel fuel fired simulator materials test rig to determine their oxidation and corrosion resistance. Sheet specimens are tested at 820 C for 3500 hr in 5 hr heating cycles. Specific weight change data and an attack parameter are used to categorize the alloys into four groups; 10 alloys show excellent for good oxidation and corrosion resistance and six alloys exhibit poor or catastrophic resistance. Metallographic, X-ray, and electron microprobe analyses aid in further characterizing the oxidation and corrosion behavior of the alloys. Alloy compositions, expecially the reactive elements aluminum, titanium, and chromium, play a major role in the excellent oxidation and corrosion behavior of the alloys. The best oxidation resistance is associated with the formation of an iron nickel aluminum outer oxide scale, an intermediate oxide scale rich in chromium and titanium, and an aluminum outer oxide scale adjacent to the metallic substrate, which exhibits a zone of internal oxidation of aluminum and to some extent titanium.

An XPS study of the stability of Fomblin Z25 on the native oxide of aluminum. [x ray photoelectron spectroscopy

NASA Technical Reports Server (NTRS)

Herrera-Fierro, Pilar; Pepper, Stephen V.; Jones, William R.

1991-01-01

Thin films of Fomblin Z25, a perfluoropolyalkylether lubricant, were vapor deposited onto clean, oxidized aluminum and sapphire surfaces, and their behavior at different temperatures was studied using x ray photoelectron spectroscopy (XPS) and thermal desorption spectroscopy (TDS). It was found that the interfacial fluid molecules decompose on the native oxide at room temperature, and continue to decompose at elevated temperatures, as previous studies had shown to occur on clean metal. TDS indicated that different degradation mechanisms were operative for clean and oxidized aluminum. On sapphire substrates, no reaction was observed at room temperature. Our conclusion is that the native oxide of aluminum is neither passive nor protective towards Fomblin Z25. At high temperatures (150 C) degradation of the polymer on sapphire produced a debris layer at the interface with a chemical composition similar to the one formed on aluminum oxide. Rubbing a Fomblin film on a single crystal sapphire also induced the decomposition of the lubricant in contact with the interface and the formulation of a debris layer.

Properties of ZnO nanocrystals prepared by radiation method

NASA Astrophysics Data System (ADS)

Čuba, Václav; Gbur, Tomáš; Múčka, Viliam; Nikl, Martin; Kučerková, Romana; Pospíšil, Milan; Jakubec, Ivo

2010-01-01

Zinc oxide nanoparticles were prepared by irradiation of aqueous solutions containing zinc(II) ions, propan-2-ol, polyvinyl alcohol, and hydrogen peroxide. Zinc oxide was found in solid phase either directly after irradiation, or after additional heat treatment. Various physicochemical parameters, including scintillation properties of prepared materials, were studied. After decomposition of impurities and annealing of oxygen vacancies, the samples showed intensive emission in visible spectral range and well-shaped exciton luminescence at 390-400 nm. The best scintillating properties had zinc oxide prepared from aqueous solutions containing zinc formate as initial precursor and hydrogen peroxide. Size of the crystalline particles ranged from tens to hundreds nm, depending on type of irradiated solution and post-irradiation thermal treatment.

Nonlinear Ultrasonic Measurements in Nuclear Reactor Environments

NASA Astrophysics Data System (ADS)

Reinhardt, Brian T.

Several Department of Energy Office of Nuclear Energy (DOE-NE) programs, such as the Fuel Cycle Research and Development (FCRD), Advanced Reactor Concepts (ARC), Light Water Reactor Sustainability, and Next Generation Nuclear Power Plants (NGNP), are investigating new fuels, materials, and inspection paradigms for advanced and existing reactors. A key objective of such programs is to understand the performance of these fuels and materials during irradiation. In DOE-NE's FCRD program, ultrasonic based technology was identified as a key approach that should be pursued to obtain the high-fidelity, high-accuracy data required to characterize the behavior and performance of new candidate fuels and structural materials during irradiation testing. The radiation, high temperatures, and pressure can limit the available tools and characterization methods. In this thesis, two ultrasonic characterization techniques will be explored. The first, finite amplitude wave propagation has been demonstrated to be sensitive to microstructural material property changes. It is a strong candidate to determine fuel evolution; however, it has not been demonstrated for in-situ reactor applications. In this thesis, finite amplitude wave propagation will be used to measure the microstructural evolution in Al-6061. This is the first demonstration of finite amplitude wave propagation at temperatures in excess of 200 °C and during an irradiation test. Second, a method based on contact nonlinear acoustic theory will be developed to identify compressed cracks. Compressed cracks are typically transparent to ultrasonic wave propagation; however, by measuring harmonic content developed during finite amplitude wave propagation, it is shown that even compressed cracks can be characterized. Lastly, piezoelectric transducers capable of making these measurements are developed. Specifically, three piezoelectric sensors (Bismuth Titanate, Aluminum Nitride, and Zinc Oxide) are tested in the Massachusetts Institute of Technology Research reactor to a fast neutron fluence of 8.65x10 20 n/cm2. It is demonstrated that Bismuth Titanate is capable of transduction up to 5 x1020 n/cm2, Zinc Oxide is capable of transduction up to 6.27 x1020 n/cm 2, and Aluminum Nitride is capable of transduction up to 8.65x x10 20 n/cm2.

Chemical stability and electrical performance of dual-active-layered zinc-tin-oxide/indium-gallium-zinc-oxide thin-film transistors using a solution process.

PubMed

Kim, Chul Ho; Rim, You Seung; Kim, Hyun Jae

2013-07-10

We investigated the chemical stability and electrical properties of dual-active-layered zinc-tin-oxide (ZTO)/indium-gallium-zinc-oxide (IGZO) structures (DALZI) with the durability of the chemical damage. The IGZO film was easily corroded or removed by an etchant, but the DALZI film was effectively protected by the high chemical stability of ZTO. Furthermore, the electrical performance of the DALZI thin-film transistor (TFT) was improved by densification compared to the IGZO TFT owing to the passivation of the pin holes or pore sites and the increase in the carrier concentration due to the effect of Sn(4+) doping.

In situ observation of the formation of hollow zinc oxide shells

DOE PAGES

Tringe, J. W.; Levie, H. W.; El-Dasher, B. S.; ...

2011-06-14

Single crystal zinc particles, 1–2 μm1–2 μm in diameter, were observed in situ with transmission electron microscopy during sublimation. The rate of sublimation is strongly dependent on the presence of a surface oxide layer. Near 375°, minimally oxidized Zn surfaces sublime in tens of seconds, consistent with a model in which the particle behaves similarly to an isolated microscale effusion cell. By contrast, zinc particles fully enclosed by oxide sublime less than one-tenth as quickly. Here these results provide new insight into the synthesis mechanisms of hollow ZnO microspheres and related structures formed from metallic zinc at elevated temperatures.

Scientific Background for Processing of Aluminum Waste

NASA Astrophysics Data System (ADS)

Kononchuk, Olga; Alekseev, Alexey; Zubkova, Olga; Udovitsky, Vladimir

2017-11-01

Changing the source of raw materials for producing aluminum and the emergence of a huge number of secondary alumina waste (foundry slag, sludge, spent catalysts, mineral parts of coal and others that are formed in various industrial enterprises) require the creation of scientific and theoretical foundations for their processing. In this paper, the aluminum alloys (GOST 4784-97) are used as an aluminum raw material component, containing the aluminum component produced as chips in the machine-building enterprises. The aluminum waste is a whole range of metallic aluminum alloys including elements: magnesium, copper, silica, zinc and iron. Analysis of the aluminum waste A1- Zn-Cu-Si-Fe shows that depending on the content of the metal the dissolution process of an aluminum alloy should be treated as the result of the chemical interaction of the metal with an alkaline solution. It is necessary to consider the behavior of the main components of alloys in an alkaline solution as applied to the system Na2O - Al2O3 - SiO2 - CO2 - H2O.

Ketamine-induced behavioural and brain oxidative changes in mice: an assessment of possible beneficial effects of zinc as mono- or adjunct therapy.

PubMed

Onaolapo, Olakunle James; Ademakinwa, Olayemi Quyyom; Olalekan, Temitayo Opeyemi; Onaolapo, Adejoke Yetunde

2017-09-01

We studied the influence of zinc, haloperidol or olanzapine on neurobehaviour (open-field, radial arm maze and elevated plus maze) and brain antioxidant status in vehicle- or ketamine-treated mice, with the aim of ascertaining the potentials of zinc in counteracting ketamine's effects. Experiment 1 assessed the effects of zinc in healthy animals and the relative degrees of modulation of ketamine's effects by zinc, haloperidol or olanzapine, respectively. Experiment 2 assessed the modulation of ketamine's effects following co-administration of zinc with haloperidol or olanzapine. Male mice weighing 18-20 g each were used. Animals were pretreated with ketamine (except vehicle, zinc, haloperidol and olanzapine controls) for 10 days before commencement of 14-day treatment (day 11-24) with vehicle, zinc, haloperidol or olanzapine (alone or in combination). Ketamine injection also continued alongside zinc and/or standard drugs in the ketamine-treated groups. Zinc, haloperidol and olanzapine were administered by gavage. Treatments were given daily and behaviours assessed on days 11 and 24. On day 24, animals were sacrificed and whole brain homogenates used for estimation of glutathione, nitric oxide and malondialdehyde (MDA) levels. Ketamine increased open-field behaviours, nitric oxide and MDA levels, while it decreased working memory, social interaction and glutathione. Administration of zinc alone or in combination with haloperidol or olanzapine was associated with variable degrees of reversal of these effects. Zinc may have the potential of a possible therapeutic agent and/or adjunct in the reversal of schizophrenia-like changes in behaviour and brain oxidative status.

21 CFR 82.3 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-04-01

...) The term mixed oxides means the sum of the quantities of aluminum, iron, calcium, and magnesium (in whatever combination they may exist in a coal-tar color) calculated as aluminum trioxide, ferric oxide, calcium oxide, and magnesium oxide. (k)-(m) [Reserved] (n) The term externally applied drugs and cosmetics...

21 CFR 82.3 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-04-01

...) The term mixed oxides means the sum of the quantities of aluminum, iron, calcium, and magnesium (in whatever combination they may exist in a coal-tar color) calculated as aluminum trioxide, ferric oxide, calcium oxide, and magnesium oxide. (k)-(m) [Reserved] (n) The term externally applied drugs and cosmetics...

Nano-Material and Structural Engineering for Thermal Highways

DTIC Science & Technology

2013-06-14

which are covered with a porous anodized aluminum oxide ( AAO ) membrane that is compatible to most if not all semiconductor electronics chips and has... aluminum oxide ( AAO ) templates as hard masks for fabrication of nanomesh thermoelectric structures. Both USPI’s and KPI’s laboratories have accumulated...T. Bigioni, M. Moskovits, and J. M. Xu, “Electrochemical fabrication of CdS nano-wire arrays in porous anodic aluminum oxide templates”, J. Phys

US-Korea Nanotechnology, Biotechnology, and Information Technology (NBIT) Symbiosys Program - Phase 1

DTIC Science & Technology

2010-10-01

diameter, length, and spacing. Fabrication Technology: Synthesis of self-organized AAO ( Anodic aluminum oxide ) templates with controlled diameter...nanowires arrayed in anodized aluminum oxide ( AAO ) templates and the diameter is precisely controlled by using atomic layer deposition (ALD) process...Jin, “Highly Self-assembled Nanotubular Aluminum Oxide by Hard Anodization ”, J. Mater. Res. (in press, December 2010). 3. J.Y. Kim, K. Noh, C. Choi

Silicon Nanostructures, Excitonic Interactions, Laser Consequences

DTIC Science & Technology

2008-07-11

etching using an anodized aluminum oxide membrane as mask. The results described here lay a solid foundation for the next phase of development aimed at...achieved though reactive-ion-etching using an anodized aluminum oxide membrane as mask. The results described here lay a solid foundation for the next...Materials, April 4, 2006 issue). 6. Aijun Yin, Marian Tzolov, David Cardimona and Jimmy Xu, "Fabrication of Highly Ordered Anodic Aluminum Oxide

Process of making supported catalyst

DOEpatents

Schwarz, James A.; Subramanian, Somasundaram

1992-01-01

Oxide supported metal catalysts have an additional metal present in intimate association with the metal catalyst to enhance catalytic activity. In a preferred mode, iridium or another Group VIII metal catalyst is supported on a titania, alumina, tungsten oxide, silica, or composite oxide support. Aluminum ions are readsorbed onto the support and catalyst, and reduced during calcination. The aluminum can be added as aluminum nitrate to the iridium impregnate solution, e.g. chloroiridic acid.

Violent oxidation of lithium-containing aluminum alloys in liquid oxygen

NASA Astrophysics Data System (ADS)

Dalins, Ilmars; Karimi, Majid; Ila, Daryush

1991-06-01

A strong exothermic and quite well known thermite reaction involving aluminum, oxygen and transition metals (Fe, Cr, Ni, etc.) has apparently been initiated during impact testing of Alcoa aluminum alloy #2090 in liquid oxygen at NASA-MSFC. In some instances, this reaction, essentially an oxidation process, has been so intense that the Inconel 718 cup containing the aluminum alloy disk and associated impacter has melted raising certain safety concerns in the use of this alloy. Reaction products as well as the test specimen surfaces have been studied with surface science techniques like XPS/ESCA, SIMS and AES. Typically, in order to initiate the thermite reaction a temperature of approximately 1000°C is necessary. The mechanism responsible for this oxidation is of great interest. The analysis of the reaction products together with a theoretical analysis, including digital modeling has been pursued. There is strong evidence that the large relaxation energy of the aluminum oxide coating, formed during the aluminum alloy cleaning process, is causing a highly localized energy release during fracture or lattice deformation which is enhancing the oxidation process to a runaway condition. The presence of alkali atoms (Li) enhances the likelihood and intensity of the oxidation reaction. The details of the surface studies will be discussed.

Auger electron spectroscopy study of initial stages of oxidation in a copper - 19.6-atomic-percent-aluminum alloy

NASA Technical Reports Server (NTRS)

Ferrante, J.

1973-01-01

Auger electron spectroscopy was used to examine the initial stages of oxidation of a polycrystalline copper - 19.6 a/o-aluminum alloy. The growth of the 55-eV aluminum oxide peak and the decay of the 59-, 62-, and 937-eV copper peaks were examined as functions of temperature, exposure, and pressure. Pressures ranged from 1x10 to the minus 7th power to 0.0005 torr of O2. Temperatures ranged from room temperature to 700 C. A completely aluminum oxide surface layer was obtained in all cases. Complete disappearance of the underlying 937-eV copper peak was obtained by heating at 700 C in O2 at 0.0005 torr for 1 hr. Temperature studies indicated that thermally activated diffusion was important to the oxidation studies. The initial stages of oxidation followed a logarithmic growth curve.

Ternary and coupled binary zinc tin oxide nanopowders: Synthesis, characterization, and potential application in photocatalytic processes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ivetić, T.B., E-mail: tamara.ivetic@df.uns.ac.rs; Finčur, N.L.; Đačanin, Lj. R.

2015-02-15

Highlights: • Mechanochemically synthesized nanocrystalline zinc tin oxide (ZTO) powders. • Photocatalytic degradation of alprazolam in the presence of ZTO water suspensions. • Coupled binary ZTO exhibits enhanced photocatalytic activity compared to ternary ZTO. - Abstract: In this paper, ternary and coupled binary zinc tin oxide nanocrystalline powders were prepared via simple solid-state mechanochemical method. X-ray diffraction, scanning electron microscopy, Raman and reflectance spectroscopy were used to study the structure and optical properties of the obtained powder samples. The thermal behavior of zinc tin oxide system was examined through simultaneous thermogravimetric-differential scanning calorimetric analysis. The efficiencies of ternary (Zn{sub 2}SnO{submore » 4} and ZnSnO{sub 3}) and coupled binary (ZnO/SnO{sub 2}) zinc tin oxide water suspensions in the photocatalytic degradation of alprazolam, short-acting anxiolytic of the benzodiazepine class of psychoactive drugs, under UV irradiation were determined and compared with the efficiency of pure ZnO and SnO{sub 2}.« less

Fabrication of Vertically Aligned Carbon Nanotube or Zinc Oxide Nanorod Arrays for Optical Diffraction Gratings.

PubMed

Kim, Jeong; Kim, Sun Il; Cho, Seong-Ho; Hwang, Sungwoo; Lee, Young Hee; Hur, Jaehyun

2015-11-01

We report on new fabrication methods for a transparent, hierarchical, and patterned electrode comprised of either carbon nanotubes or zinc oxide nanorods. Vertically aligned carbon nanotubes or zinc oxide nanorod arrays were fabricated by either chemical vapor deposition or hydrothermal growth, in combination with photolithography. A transparent conductive graphene layer or zinc oxide seed layer was employed as the transparent electrode. On the patterned surface defined using photoresist, the vertically grown carbon nanotubes or zinc oxides could produce a concentrated electric field under applied DC voltage. This periodic electric field was used to align liquid crystal molecules in localized areas within the optical cell, effectively modulating the refractive index. Depending on the material and morphology of these patterned electrodes, the diffraction efficiency presented different behavior. From this study, we established the relationship between the hierarchical structure of the different electrodes and their efficiency for modulating the refractive index. We believe that this study will pave a new path for future optoelectronic applications.

Comparative Study of Antidiabetic Activity and Oxidative Stress Induced by Zinc Oxide Nanoparticles and Zinc Sulfate in Diabetic Rats.

PubMed

Nazarizadeh, Ali; Asri-Rezaie, Siamak

2016-08-01

In the current study, antidiabetic activity and toxic effects of zinc oxide nanoparticles (ZnO) were investigated in diabetic rats compared to zinc sulfate (ZnSO4) with particular emphasis on oxidative stress parameters. One hundred and twenty male Wistar rats were divided into two healthy and diabetic groups, randomly. Each major group was further subdivided into five subgroups and then orally supplemented with various doses of ZnO (1, 3, and 10 mg/kg) and ZnSO4 (30 mg/kg) for 56 consecutive days. ZnO showed greater antidiabetic activity compared to ZnSO4 evidenced by improved glucose disposal, insulin levels, and zinc status. The altered activities of erythrocyte antioxidant enzymes as well as raised levels of lipid peroxidation and a marked reduction of total antioxidant capacity were observed in rats receiving ZnO. ZnO nanoparticles acted as a potent antidiabetic agent, however, severely elicited oxidative stress particularly at higher doses.

Green Synthesis of Formulated Zinc Oxide Nanoparticles for Chemical Protection of Skin Care and Related Applications

NASA Astrophysics Data System (ADS)

Koppolu, Ramya

Nanomaterials have diversified applications based on the unique properties. These nanoparticles and functionalized nanocomposites have been studied in the health care filed. Nanoparticles are mostly used in sunscreens which are a part of human life. These sunscreens consist of titanium dioxide and zinc oxide nanoparticles. Due to the higher band crevices, they help the skin to protect from ultraviolet rays, for instance, ultraviolet B and ultraviolet A. A series of nanostructured zinc oxide nanoparticles were prepared by cost-effective chemical and bioinspired methods and variables were optimized. Highly stable and spherical zinc oxide nanoparticles were formulated by aloe vera ( Aloe barbadensis) plant extract and avocado (Persea americana Mill) fruit extract. The state-of-the-art instrumentation was used to characterize the morphology, elemental composition, and particle size distribution. X-ray diffraction data indicated highly crystalline and ultrafine nanoparticles were obtained from the colloidal methods. The X-ray photoelectron spectroscopy results showed the chemical state of zinc, carbon, and oxygen atoms were well-indexed and are used as fingerprint identification of the elements. Transmission electron microscopy images show the shape of particles were cubic and fiber shape contingent upon the protecting operators and heat treatment conditions. The toxicity studies of zinc oxide nanoparticles were found to cause an increase in nitric oxide, which is protecting against further oxidative stress and appears to be nontoxic.

Copper Doping of Zinc Oxide by Nuclear Transmutation

DTIC Science & Technology

2014-03-27

Copper Doping of Zinc Oxide by Nuclear Transmutation THESIS Matthew C. Recker, Captain, USAF AFIT-ENP-14-M-30 DEPARTMENT OF THE AIR FORCE AIR...NUCLEAR TRANSMUTATION THESIS Presented to the Faculty Department of Engineering Physics Graduate School of Engineering and Management Air Force...COPPER DOPING OF ZINC OXIDE BY NUCLEAR TRANSMUTATION Matthew C. Recker, BS Captain, USAF Approved: //signed// 27 February 2014 John W. McClory, PhD

Effect of annealing temperature on optical properties of binary zinc tin oxide nano-composite prepared by sol-gel route using simple precursors: structural and optical studies by DRS, FT-IR, XRD, FESEM investigations.

PubMed

Habibi, Mohammad Hossein; Mardani, Maryam

2015-02-25

Binary zinc tin oxide nano-composite was synthesized by a facile sol-gel method using simple precursors from the solutions consisting of zinc acetate, tin(IV) chloride and ethanol. Effect of annealing temperature on optical and structural properties was investigated using X-ray diffraction (XRD), diffuse reflectance spectra (DRS), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). XRD results revealed the existence of the ZnO and SnO2 phases. FESEM results showed that binary zinc tin oxide nano-composites ranges from 56 to 60 nm in diameter at 400°C and 500°C annealing temperatures respectively. The optical band gap was increased from 2.72 eV to 3.11 eV with the increasing of the annealing temperature. FTIR results confirmed the presence of zinc oxide and tin oxide and the broad absorption peaks at 3426 and 1602 cm(-1) can be ascribed to the vibration of absorptive water, and the absorption peaks at 546, 1038 and 1410 cm(-1) are due to the vibration of Zn-O or Sn-O groups in binary zinc tin oxide. Copyright © 2014 Elsevier B.V. All rights reserved.

Enhancement in sensitivity of graphene-based zinc oxide assisted bimetallic surface plasmon resonance (SPR) biosensor

NASA Astrophysics Data System (ADS)

Kumar, Rajeev; Kushwaha, Angad S.; Srivastava, Monika; Mishra, H.; Srivastava, S. K.

2018-03-01

In the present communication, a highly sensitive surface plasmon resonance (SPR) biosensor with Kretschmann configuration having alternate layers, prism/zinc oxide/silver/gold/graphene/biomolecules (ss-DNA) is presented. The optimization of the proposed configuration has been accomplished by keeping the constant thickness of zinc oxide (32 nm), silver (32 nm), graphene (0.34 nm) layer and biomolecules (100 nm) for different values of gold layer thickness (1, 3 and 5 nm). The sensitivity of the proposed SPR biosensor has been demonstrated for a number of design parameters such as gold layer thickness, number of graphene layer, refractive index of biomolecules and the thickness of biomolecules layer. SPR biosensor with optimized geometry has greater sensitivity (66 deg/RIU) than the conventional (52 deg/RIU) as well as other graphene-based (53.2 deg/RIU) SPR biosensor. The effect of zinc oxide layer thickness on the sensitivity of SPR biosensor has also been analysed. From the analysis, it is found that the sensitivity increases significantly by increasing the thickness of zinc oxide layer. It means zinc oxide intermediate layer plays an important role to improve the sensitivity of the biosensor. The sensitivity of SPR biosensor also increases by increasing the number of graphene layer (upto nine layer).

Demonstration and Validation of a Regenerated Cellulose Dialysis Membrane Diffusion Sampler for Monitoring Groundwater Quality and Remediation Progress at DoD Sites

DTIC Science & Technology

2007-02-01

years if kept refrigerated in its preservative solution of ethanol, sodium benzoate , and ethylene diamine tetra-acetic acid (EDTA). Alternatively... sodium bicarbonate solution, EDTA, and sodium azide solution to remove residual gylcerol, sulfide, cadmium, chromium, copper, iron, nickel, zinc, and lead...Magnesium Cadmium Nickel Potassium Chromium Selenium Sodium Copper Vanadium Aluminum Iron Zinc Arsenic Lead Antimony Manganese Anions (1-3 days

The Properties of Fluorine, Oxygen Bifluoride, and Chlorine Trifluoride

DTIC Science & Technology

1949-09-06

they should be of forg€;d steel. Welded joints are excellent provided the welds are slag -free. Cast iron or any ether material containing silica cannot...400°C brilliant light Manganese powder form; 500°C formation of fluoride with glowing Zinc Cadmium powder form; heating glowing and flashing...reaction upon heating Magnesium at first, no reaction; explosive reaction Aluminum after ignition with carbon Zinc TV „ 1X11 Lead Cupfier L

Effect of Chromate and Chromate-Free Organic Coatings on Corrosion Fatigue of an Aluminum Alloy

DTIC Science & Technology

2012-02-20

Investigations of alloy AA7075 corrosion in acid rain solution, inhibited by chromate-free blends of zinc phosphate with bentonite, zeolite and calcium...with solution components. Single use of zinc phosphate and these ion exchanged pigments for corrosion inhibition do not provide desired effect...primer performance against corrosion fatigue cracking under a commercial polyurethane topcoat. As a control , they used samples of chromated AA2024

Synthesis of (Hexaconazole-Zinc/Aluminum-Layered Double Hydroxide Nanocomposite) Fungicide Nanodelivery System for Controlling Ganoderma Disease in Oil Palm.

PubMed

Mustafa, Isshadiba F; Hussein, Mohd Zobir; Saifullah, Bullo; Idris, Abu Seman; Hilmi, Nur Hailini Z; Fakurazi, Sharida

2018-01-31

A fungicide, hexaconazole was successfully intercalated into the intergalleries of zinc/aluminum-layered double hydroxide (ZALDH) using the ion-exchange method. Due to the intercalation of hexaconazole, the basal spacing of the ZALDH was increased from 8.7 Å in ZALDH to 29.4 Å in hexaconazole-intercalated ZALDH (HZALDH). The intercalation of hexaconazole into the interlayer of the nanocomposite was confirmed using the Fourier-transform infrared (FTIR) study. This supramolecular chemistry intercalation process enhanced the thermal stability of the hexaconazole moiety. The fungicide loading was estimated to be 51.8%. The nanodelivery system also shows better inhibition toward the Ganoderma boninense growth than the counterpart, free hexaconazole. The results from this work have a great potential to be further explored for combating basal stem rot (BSR) disease in oil palm plantation.

Titanium, aluminum and zinc complexes containing diamine-bis(benzotriazole phenolate) ligands: Synthesis, structural characterization and catalytic studies for ring-opening polymerization of ε-caprolactone

NASA Astrophysics Data System (ADS)

Liu, Zheng-Tang; Li, Chen-Yu; Chen, Jhy-Der; Liu, Wan-Ling; Tsai, Chen-Yen; Ko, Bao-Tsan

2017-04-01

Structurally diverse metal complexes bearing diamine-bis(benzotriazole phenolate) (DiBTP) ligands have been synthesized and fully characterized by single crystal X-ray crystallography. The reaction of Ti(OiPr)4 with C8MEADiBTP-H2 or C8BEADiBTP-H2 (1.0 mol equiv.) generated the monomeric titanium alkoxy complexes [(C8MEADiBTP)Ti(OiPr)2] (1) and [(C8BEADiBTP)Ti(OiPr)2] (2), respectively. Moreover, C8BEADiBTP-H2 reacted with 2.0 molar equiv. of AlMe3 to give the tetra-coordinated di-aluminum complex [(C8BEADiBTP)Al2Me4] (3). Zinc complex [(C8BEADiBTP)Zn2Et2] (4) could be obtained by the alkane elimination of ZnEt2 (2.0 equiv.) with C8BEADiBTP-H2 as the pro-ligand under similar synthetic methods in good yield. Single-crystal X-ray diffraction indicates that 3 is a bimetallic aluminum dimethyl complex with a tetradentate C8BEADiBTP moiety chelating two metal atoms, whereas complex 4 displays the dinuclear feature containing both tetra- and penta-coordinated zinc atoms bonded by one ONNON-pentadentate C8BEADiBTP ligand. Catalytic studies for ring-opening polymerization of ε-caprolactone of complex 1-4 were systematic explored; the comparative studies of such polymerization were also discussed.

Corrosion Protection of Al/Au/ZnO Anode for Hybrid Cell Application

PubMed Central

Slaughter, Gymama; Stevens, Brian

2015-01-01

Effective protection of power sources from corrosion is critical in the development of abiotic fuel cells, biofuel cells, hybrid cells and biobateries for implantable bioelectronics. Corrosion of these bioelectronic devices result in device inability to generate bioelectricity. In this paper Al/Au/ZnO was considered as a possible anodic substrate for the development of a hybrid cell. The protective abilities of corrosive resistant aluminum hydroxide and zinc phosphite composite films formed on the surface of Al/Au/ZnO anode in various electrolyte environments were examined by electrochemical methods. The presence of phosphate buffer and physiological saline (NaCl) buffer allows for the formation of aluminum hyrdroxide and zinc phosphite composite films on the surface of the Al/Au/ZnO anode that prevent further corrosion of the anode. The highly protective films formed on the Al/Au/ZnO anode during energy harvesting in a physiological saline environment resulted in 98.5% corrosion protective efficiency, thereby demonstrating that the formation of aluminum hydroxide and zinc phosphite composite films are effective in the prevention of anode corrosion during energy harvesting. A cell assembly consisting of the Al/Au/ZnO anode and platinum cathode resulted in an open circuit voltage of 1.03 V. A maximum power density of 955.3 μW/ cm2 in physiological saline buffer at a cell voltage and current density of 345 mV and 2.89 mA/ cm2, respectively. PMID:26580661

Corrosion Protection of Al/Au/ZnO Anode for Hybrid Cell Application.

PubMed

Slaughter, Gymama; Stevens, Brian

2015-11-16

Effective protection of power sources from corrosion is critical in the development of abiotic fuel cells, biofuel cells, hybrid cells and biobateries for implantable bioelectronics. Corrosion of these bioelectronic devices result in device inability to generate bioelectricity. In this paper Al/Au/ZnO was considered as a possible anodic substrate for the development of a hybrid cell. The protective abilities of corrosive resistant aluminum hydroxide and zinc phosphite composite films formed on the surface of Al/Au/ZnO anode in various electrolyte environments were examined by electrochemical methods. The presence of phosphate buffer and physiological saline (NaCl) buffer allows for the formation of aluminum hyrdroxide and zinc phosphite composite films on the surface of the Al/Au/ZnO anode that prevent further corrosion of the anode. The highly protective films formed on the Al/Au/ZnO anode during energy harvesting in a physiological saline environment resulted in 98.5% corrosion protective efficiency, thereby demonstrating that the formation of aluminum hydroxide and zinc phosphite composite films are effective in the prevention of anode corrosion during energy harvesting. A cell assembly consisting of the Al/Au/ZnO anode and platinum cathode resulted in an open circuit voltage of 1.03 V. A maximum power density of 955.3 mW/ cm² in physiological saline buffer at a cell voltage and current density of 345 mV and 2.89 mA/ cm², respectively.

AFM AND XPS Characterization of Zinc-Aluminum Alloy Coatings with Attention to Surface Dross and Flow Lines

NASA Astrophysics Data System (ADS)

Harding, Felipe A.; Alarcon, Nelson A.; Toledo, Pedro G.

Surfaces of various zinc-aluminum alloy (Zn-Al) coated steel samples are studied with attention to foreign surface dross by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS/ESCA). AFM topographic maps of zinc-aluminum alloy surfaces free of dross reveal the perfect nanoscale details of two kinds of dendrites: branched and globular. In all magnifications the dendrites appear smooth and, in general, very clean. XPS analysis of the extreme surface of a Zn-Al sample reveals Al, Zn, Si and O as the main components. The XPS results show no segregation or separation of phases other than those indicated by the ternary Al-Zn-Si diagram. For surfaces of Zn-Al plagued with impurities, high resolution AFM topographic maps reveal three situations: (1) areas with well-defined dendrites, relatively free of dross; (2) areas with small, millimeter-sized black spots known as dross; and (3) areas with large black stains, known as flow lines. Dendrite deformation and dross accumulation increase notably in the neighborhood, apparently clean to the naked eye, of dross or flow lines. XPS results of areas with dross and flow lines indicate unacceptable high concentration of Si and important Si phase separation. These results, in the light of AFM work, reveal that dross and flow lines are a consequence of a high local concentration of Si from high melting point silica and silicate impurities in the Zn-Al alloy source.

Metallic Thin-Film Bonding and Alloy Generation

NASA Technical Reports Server (NTRS)

Peotter, Brian S. (Inventor); Fryer, Jack Merrill (Inventor); Campbell, Geoff (Inventor); Droppers, Lloyd (Inventor)

2016-01-01

Diffusion bonding a stack of aluminum thin films is particularly challenging due to a stable aluminum oxide coating that rapidly forms on the aluminum thin films when they are exposed to atmosphere and the relatively low meting temperature of aluminum. By plating the individual aluminum thin films with a metal that does not rapidly form a stable oxide coating, the individual aluminum thin films may be readily diffusion bonded together using heat and pressure. The resulting diffusion bonded structure can be an alloy of choice through the use of a carefully selected base and plating metals. The aluminum thin films may also be etched with distinct patterns that form a microfluidic fluid flow path through the stack of aluminum thin films when diffusion bonded together.

Immobilization Effect of Morphological, Thermal and Optical Properties in Biotemplate on Zinc Oxide Nanocomposite from Chitosan

NASA Astrophysics Data System (ADS)

Karpuraranjith, M.; Thambidurai, S.

Biotemplate-based zinc oxide nanocomposite was effectively prepared via simple chemical precipitation route. The functional groups of amino (-NH2), hydroxyl (-OH) and O-Zn-O were confirmed and characterized by FTIR spectroscopy. The structural and morphological properties were confirmed by XRD, UV-Vis DRS, HR-SEM and TEM analyses. The elemental composition of carbon, nitrogen, zinc and oxygen was confirmed by energy-dispersive X-ray analysis (EDAX) and Brunauer-Emmett-Teller high surface area of materials was estimated to be 52.49m2/g, respectively. Thermogravimetric analysis (TGA) shows that biotemplate on zinc oxide nanocomposite has higher thermal stability than chitosan matrix. The results demonstrate that biotemplate on zinc oxide matrix causes immobilization effect among the two components. Therefore, chitosan-ZnO nanocomposite has a microcrystalline morphological structure and also good thermal stability, so it can be a promising material for sensors, medical, tissue engineering and wastewater treatment applications.

Novel green synthetic strategy to prepare ZnO nanocrystals using rambutan (Nephelium lappaceum L.) peel extract and its antibacterial applications.

PubMed

Yuvakkumar, R; Suresh, J; Nathanael, A Joseph; Sundrarajan, M; Hong, S I

2014-08-01

In the present investigation, we report a sustainable novel green synthetic strategy to synthesis zinc oxide nanocrystals. This is the first report on sustainable biosynthesis of zinc oxide nanocrystals employing Nephelium lappaceum L., peel extract as a natural ligation agent. Green synthesis of zinc oxide nanocrystals was carried out via zinc-ellagate complex formation using rambutan peel wastes. The successful formation of zinc oxide nanocrystals was confirmed employing standard characterisation studies. A possible mechanism for the formation of ZnO nanocrystals with rambutan peel extract was also proposed. The prepared ZnO nanocrystals were coated on the cotton fabric and their antibacterial activity were analyzed. ZnO nanocrystals coated cotton showed good antibacterial activity towards Escherichia coli (E. coli), gram negative bacteria and Staphylococcus aureus (S. aureus), gram positive bacteria. Copyright © 2014 Elsevier B.V. All rights reserved.

Concentrations and bioaccessibility of metals in vegetation and dust near a mining haul road, Cape Krusenstern National Monument, Alaska

USGS Publications Warehouse

Brumbaugh, William G.; Morman, Suzette A.; May, Thomas W.

2011-01-01

Vegetation, sub-surface peat, and road dust were sampled near the Delong Mountain Transportation System (DMTS) haul road in northwest Alaska in 2005-2006 to document aluminum, barium, cadmium, lead, and zinc concentrations, and to evaluate bioaccessibility of these metals. The DMTS haul road is the transport corridor between Red Dog Mine (a large-scale, lead-zinc mine and mill) and the coastal shipping port, and it traverses National Park Service lands. Compared to reference locations, total metal concentrations in four types of vegetation (birch, cranberry, and willow leaves, and cotton grass blades/stalks) collected 25 m from the haul road were enriched on average by factors of 3.5 for zinc, 8.0 for barium, 20 for cadmium, and 150 for lead. Triple rinsing of vegetation with a water/methanol mixture reduced metals concentrations by at most 50%, and cadmium and zinc concentrations were least affected by rinsing. Cadmium and zinc bioaccessibility was greater in vegetation (50% to 100%) than in dust (15% to 20%); whereas the opposite pattern was observed for lead bioaccessibility (<30% in vegetation; 50% in dust). Barium exhibited low-to-intermediate bioaccessibility in dust and vegetation (20% to 40%), whereas aluminum bioaccessibility was relatively low (<6%) in all sample types. Our reconnaissance-level study indicates that clean-up and improvements in lead/zinc concentrate transfer activities have been effective; however, as of 2006, metal dispersion from past and/or present releases of fugitive dusts along the DMTS road still may have been contributing to elevated metals in surface vegetation. Vegetation was most enriched in lead, but because bioaccessibility of cadmium was greater, any potential risks to animals that forage near the haul road might be equally important for both of these metals.

Proceedings of the International Pyrotechnics Seminar (6th) Held at Estes Park, Colorado, 17-21 July 1978

DTIC Science & Technology

1978-06-01

in metal form, and not as an oxide , as with conventional HC compositions. "That verified the fact that the aluminum did not take part in the chemical...the melting of the protective oxide layer on the aluminum particle with an attendant increase in surface reaction rate leading to ignition. Oxide ...detonation 5 aluminum BrF5 partial detonation 6 propylene oxide ClF3 partial detonation 621 041 IR! Each teat used about 5 kg of fuel, about 400 g

Effects of various additives on sintering of aluminum nitride

NASA Technical Reports Server (NTRS)

Komeya, K.; Inoue, H.; Tsuge, A.

1982-01-01

Effects of thirty additives on sintering A/N were investigated. The addition of alkali earth oxides and rare earth oxides gave fully densified aluminum nitride. This is due to the formation of nitrogen-containing aluminate liquid in the system aluminum nitride-alkali earth oxides or rare earth oxides. Microstructural studies of the sintered specimens with the above two types of additives suggested that the densification was due to the liquid phase sintering. Additions of silicon compounds resulted in poor densification by the formation of highly refractory compounds such as A/N polytypes.

Niobium-aluminum base alloys having improved, high temperature oxidation resistance

NASA Technical Reports Server (NTRS)

Hebsur, Mohan G. (Inventor); Stephens, Joseph R. (Inventor)

1991-01-01

A niobium-aluminum base alloy having improved oxidation resistance at high temperatures and consisting essentially of 48%-52% niobium, 36%-42% aluminum, 4%-10% chromium, 0%-2%, more preferably 1%-2%, silicon and/or tungsten with tungsten being preferred, and 0.1%-2.0% of a rare earth selected from the group consisting of yttrium, ytterbium and erbium. Parabolic oxidation rates, k.sub.p, at 1200.degree. C. range from about 0.006 to 0.032 (mg/cm.sup.2).sup.2 /hr. The new alloys also exhibit excellent cyclic oxidation resistance.

High specific heat superconducting composite

DOEpatents

Steyert, Jr., William A.

1979-01-01

A composite superconductor formed from a high specific heat ceramic such as gadolinium oxide or gadolinium-aluminum oxide and a conventional metal conductor such as copper or aluminum which are insolubly mixed together to provide adiabatic stability in a superconducting mode of operation. The addition of a few percent of insoluble gadolinium-aluminum oxide powder or gadolinium oxide powder to copper, increases the measured specific heat of the composite by one to two orders of magnitude below the 5.degree. K. level while maintaining the high thermal and electrical conductivity of the conventional metal conductor.

Application of nanodimensional particles and aluminum hydroxide nanostructures for cancer diagnosis and therapy

NASA Astrophysics Data System (ADS)

Korovin, M. S.; Fomenko, A. N.

2017-09-01

Nanoparticles and nanostructured materials are one of the most promising developments for cancer therapy. Gold nanoparticles, magnetic nanoparticles based on iron and its oxides and other metal oxides have been widely used in diagnosis and treatment of cancer. Much less researchers' attention has been paid to nanoparticles and nanostructures based on aluminum oxides and hydroxides as materials for cancer diagnosis and treatment. However, recent investigations have shown promising results regarding these objects. Here, we review the antitumor results obtained with different aluminum oxide/hydroxide nanoparticles and nanostructures.

Fullerene Derivatives and Aluminum-based Nanothermites as Potential New Ammunition Primers

DTIC Science & Technology

2013-03-01

such as RDX. In a thermite type reaction, a metal oxide is the oxidant and the fuel is aluminum. The nanothermites are generally composed of aluminum...and metal oxide nanopowders, unlike conventional thermite used for several years, which are composed of micron sized powders. The rate of release of...energy in conventional thermite is relatively slow in comparison with conventional energetic materials. The typical velocity of propagation of combustion

Investigation of Dispersion, Stability, and Tribological Performance of Oil-Based Aluminum Oxide Nanofluids

DTIC Science & Technology

2012-01-01

protection of the 4140 steel using the alumina nanoparticles. This means that the alumina particles primarily acted as third body abrasives in this...INVESTIGATION OF DISPERSION, STABILITY, AND TRIBOLOGICAL PERFORMANCE OF OIL-BASED ALUMINUM OXIDE NANOFLUIDS THESIS FOR THE... TRIBOLOGICAL PERFORMANCE OF OIL-BASED ALUMINUM OXIDE NANOFLUIDS 5a. CONTRACT NUMBER W56H2V-08-C-0236 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6

Ginkgo biloba extract alleviates oxidative stress and some neurotransmitters changes induced by aluminum chloride in rats.

PubMed

Mohamed, Naglaa El-Shahat; Abd El-Moneim, Ahmed E

2017-03-01

In the present study, twenty four adult male albino rats were classified into four groups. The control group received normal diet and water; the second group was treated daily with oral dose of Ginkgo biloba (200 mg/kg body weight [b.wt]) for 3 mo; the third group was treated daily with oral dose of aluminum chloride (10 mg/kg b.wt) for 3 mo; and the fourth group was treated with both Ginkgo biloba and aluminum chloride (200 and 10 mg/kg b.wt, respectively) using a stomach tube for 3 mo. The results showed that administration of AlCl 3 to rats induced significant increase (P < 0.05) in thiobarbituric acid reactive substance and decrease (P < 0.05) in glutathione, catalase, and superoxide dismutase in brain and testis homogenates. The data also showed significant decrease (P < 0.05) in noradrenaline, dopamine, and serotonin (5-HT) levels in brain tissue. The rats administered AlCl 3 showed significant decrease (P < 0.05) in serum zinc (Zn) and copper (Cu), significant increase (P < 0.05) in serum iron (Fe), and non-significant decrease in magnesium (Mg). Furthermore, significant increase (P < 0.05) in serum alkaline phosphatase and acid phosphatase and significant decrease (P < 0.05) in testosterone were recorded. The histologic examination showed some degenerative changes in both brain and testis tissues while significant improvement in biochemical and histologic changes were observed in the aluminum chloride plus Ginkgo biloba group. It could be concluded that the protective effect of Ginkgo biloba may be attributed to its antioxidant properties. Copyright © 2017 Elsevier Inc. All rights reserved.

Bioavailability of Zinc in Wistar Rats Fed with Rice Fortified with Zinc Oxide

PubMed Central

Della Lucia, Ceres Mattos; Santos, Laura Luiza Menezes; Rodrigues, Kellen Cristina da Cruz; Rodrigues, Vivian Cristina da Cruz; Martino, Hércia Stampini Duarte; Pinheiro Sant’Ana, Helena Maria

2014-01-01

The study of zinc bioavailability in foods is important because this mineral intake does not meet the recommended doses for some population groups. Also, the presence of dietary factors that reduce zinc absorption contributes to its deficiency. Rice fortified with micronutrients (Ultra Rice®) is a viable alternative for fortification since this cereal is already inserted into the population habit. The aim of this study was to evaluate the bioavailability of zinc (Zn) in rice fortified with zinc oxide. During 42 days, rats were divided into four groups and fed with diets containing two different sources of Zn (test diet: UR® fortified with zinc oxide, or control diet: zinc carbonate (ZnCO3)), supplying 50% or 100%, respectively, of the recommendations of this mineral for animals. Weight gain, food intake, feed efficiency ratio, weight, thickness and length of femur; retention of zinc, calcium (Ca) and magnesium (Mg) in the femur and the concentrations of Zn in femur, plasma and erythrocytes were evaluated. Control diet showed higher weight gain, feed efficiency ratio, retention of Zn and Zn concentration in the femur (p < 0.05). However, no differences were observed (p > 0.05) for dietary intake, length and thickness of the femur, erythrocyte and plasmatic Zn between groups. Although rice fortified with zinc oxide showed a lower bioavailability compared to ZnCO3, this food can be a viable alternative to be used as a vehicle for fortification. PMID:24932657

Scale-up synthesis of zinc borate from the reaction of zinc oxide and boric acid in aqueous medium

NASA Astrophysics Data System (ADS)

Kılınç, Mert; Çakal, Gaye Ö.; Yeşil, Sertan; Bayram, Göknur; Eroğlu, İnci; Özkar, Saim

2010-11-01

Synthesis of zinc borate was conducted in a laboratory and a pilot scale batch reactor to see the influence of process variables on the reaction parameters and the final product, 2ZnO·3B 2O 3·3.5H 2O. Effects of stirring speed, presence of baffles, amount of seed, particle size and purity of zinc oxide, and mole ratio of H 3BO 3:ZnO on the zinc borate formation reaction were examined at a constant temperature of 85 °C in a laboratory (4 L) and a pilot scale (85 L) reactor. Products obtained from the reaction in both reactors were characterized by chemical analysis, X-ray diffraction, particle size distribution analysis, thermal gravimetric analysis and scanning electron microscopy. The kinetic data for the zinc borate production reaction was fit by using the logistic model. The results revealed that the specific reaction rate, a model parameter, decreases with increase in particle size of zinc oxide and the presence of baffles, but increases with increase in stirring speed and purity of zinc oxide; however, it is unaffected with the changes in the amount of seed and reactants ratio. The reaction completion time is unaffected by scaling-up.

Investigations into Recycling Zinc from Used Metal Oxide Varistors via pH Selective Leaching: Characterization, Leaching, and Residue Analysis

PubMed Central

Gutknecht, Toni; Gustafsson, Anna; Forsgren, Christer; Steenari, Britt-Marie

2015-01-01

Metal oxide varistors (MOVs) are a type of resistor with significantly nonlinear current-voltage characteristics commonly used in power lines to protect against overvoltages. If a proper recycling plan is developed MOVs can be an excellent source of secondary zinc because they contain over 90 weight percent zinc oxide. The oxides of antimony, bismuth, and to a lesser degree cobalt, manganese, and nickel are also present in varistors. Characterization of the MOV showed that cobalt, nickel, and manganese were not present in the varistor material at concentrations greater than one weight percent. This investigation determined whether a pH selective dissolution (leaching) process can be utilized as a starting point for hydrometallurgical recycling of the zinc in MOVs. This investigation showed it was possible to selectively leach zinc from the MOV without coleaching of bismuth and antimony by selecting a suitable pH, mainly higher than 3 for acids investigated. It was not possible to leach zinc without coleaching of manganese, cobalt, and nickel. It can be concluded from results obtained with the acids used, acetic, hydrochloric, nitric, and sulfuric, that sulfate leaching produced the most desirable results with respect to zinc leaching and it is also used extensively in industrial zinc production. PMID:26421313

Anodic Behavior of the Aluminum Current Collector in Imide-Based Electrolytes: Influence of Solvent, Operating Temperature, and Native Oxide-Layer Thickness.

PubMed

Meister, Paul; Qi, Xin; Kloepsch, Richard; Krämer, Elisabeth; Streipert, Benjamin; Winter, Martin; Placke, Tobias

2017-02-22

The inability of imide salts to form a sufficiently effective passivation layer on aluminum current collectors is one of the main obstacles that limit their broad application in electrochemical energy-storage systems. However, under certain circumstances, the use of electrolytes with imide electrolyte salts in combination with the aluminum current collector is possible. In this contribution, the stability of the aluminum current collector in electrolytes containing either lithium bis(trifluoromethanesulfonyl) imide (LiTFSI) or lithium fluorosulfonyl-(trifluoromethanesulfonyl) imide (LiFTFSI) as conductive salt was investigated by electrochemical techniques, that is, cyclic voltammetry (CV) and chronocoulometry (CC) in either room-temperature ionic liquids or in ethyl methyl sulfone. In particular, the influence of the solvent, operating temperature, and thickness of the native oxide layer of aluminum on the pit formation at the aluminum current collector surface was studied by means of scanning electron microscopy. In general, a more pronounced aluminum dissolution and pit formation was found at elevated temperatures as well as in solvents with a high dielectric constant. An enhanced thickness of the native aluminum oxide layer increases the oxidative stability versus dissolution. Furthermore, we found a different reaction rate depending on dwell time at the upper cut-off potential for aluminum dissolution in TFSI- and FTFSI-based electrolytes during the CC measurements; the use of LiFTFSI facilitated the dissolution of aluminum compared to LiTFSI. Overall, the mechanism of anodic aluminum dissolution is based on: i) the attack of the Al 2 O 3 surface by acidic species and ii) the dissolution of bare aluminum into the electrolyte, which, in turn, is influenced by the electrolyte's dielectric constant. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Acetone sensor based on zinc oxide hexagonal tubes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hastir, Anita, E-mail: anitahastir@gmail.com; Singh, Onkar, E-mail: anitahastir@gmail.com; Anand, Kanika, E-mail: anitahastir@gmail.com

2014-04-24

In this work hexagonal tubes of zinc oxide have been synthesized by co-precipitation method. For structural, morphological, elemental and optical analysis synthesized powders were characterized by using x-ray diffraction, field emission scanning microscope, EDX, UV-visible and FTIR techniques. For acetone sensing thick films of zinc oxide have been deposited on alumina substrate. The fabricated sensors exhibited maximum sensing response towards acetone vapour at an optimum operating temperature of 400°C.

Bandgap-Engineered Zinc-Tin-Oxide Thin Films for Ultraviolet Sensors.

PubMed

Cheng, Tien-Hung; Chang, Sheng-Po; Chang, Shoou-Jinn

2018-07-01

Zinc-tin-oxide thin-film transistors were prepared by radio frequency magnetron co-sputtering, while an identical zinc-tin-oxide thin film was deposited simultaneously on a clear glass substrate to facilitate measurements of the optical properties. When we adjusted the deposition power of ZnO and SnO2, the bandgap of the amorphous thin film was dominated by the deposition power of SnO2. Since the thin-film transistor has obvious absorption in the ultraviolet region owing to the wide bandgap, the drain current increases with the generation of electron-hole pairs. As part of these investigations, a zinc-tin-oxide thin-film transistor has been fabricated that appears to be very promising for ultraviolet applications.

Determining the Effect of Aluminum Oxide Nanoparticles on the Aggregation of Amyloid-Beta in Transgenic Caenorhabditis elegans

NASA Astrophysics Data System (ADS)

Patel, Suhag; Matticks, John; Howell, Carina

2014-03-01

The cause of Alzheimer's disease has been linked partially to genetic factors but the predicted environmental components have yet to be determined. In Alzheimer's, accumulation of amyloid-beta protein in the brain forms plaques resulting in neurodegeneration and loss of mental functions. It has been postulated that aluminum influences the aggregation of amyloid-beta. To test this hypothesis, transgenic Caenorhabditis elegans, CL2120, was used as a model organism to observe neurodegeneration in nematodes exposed to aluminum oxide nanoparticles. Behavioral testing, fluorescent staining, and fluorescence microscopy were used to test the effects of aggregation of amyloid-beta in the nervous systems of effected nematodes exposed to aluminum oxide nanoparticles. Energy-dispersive x-ray spectroscopy was used to quantify the total concentration of aluminum oxide that the worms were exposed to during the experiment. Exposure of transgenic and wild type worms to a concentration of 4 mg mL-1 aluminum oxide showed a decrease in the sinusoidal motion, as well as an infirmity of transgenic worms when compared to control worms. These results support the hypothesis that aluminum may play a role in neurodegeneration in C. elegans, and may influence and increase the progression of Alzheimer's disease. This work was supported by National Science Foundation grants DUE-1058829, DMR-0923047 DUE-0806660 and Lock Haven FPDC grants.

Electrical characterization of anodic alumina substrate with via-in-pad structure

NASA Astrophysics Data System (ADS)

Kim, Moonjung

2013-10-01

An anodic alumina substrate has been developed as a package substrate for dynamic random access memory devices. Unlike the conventional package substrates commonly made by laminating an epoxy-based core and cladding with copper, this substrate is fabricated using aluminum anodization technology. The anodization process produces a thick aluminum oxide layer on the aluminum substrate to be used as a dielectric layer. Placing copper patterns on the anodic aluminum oxide layer forms a new substrate structure that consists of a layered structure of aluminum, anodic aluminum oxide, and copper. Using selective anodization in the fabrication process, a via structure connecting the top copper layer and bottom aluminum layer is demonstrated. Additionally, by putting vias directly in the bond and ball pads in the substrate design, the via-in-pad structure is applied in this work. These two-layer metal structures and via-in-pad arrangements make routing easier and thus provide more design flexibility. Additionally, this new package substrate has improved the power distribution network impedance given the characteristics of these structures.

Lead-free precussion primer mixes based on metastable interstitial composite (MIC) technology

DOEpatents

Dixon, George P.; Martin, Joe A.; Thompson, Don

1998-01-01

A lead-free percussion primer composition and a percussion cup containing e composition. The lead-free percussion primer composition is comprised of a mixture of about 45 wt % aluminum powder having an outer coating of aluminum oxide and molybdenum trioxide powder or a mixture of about 50 wt % aluminum powder having an outer coating of aluminum oxide and polytetrafluoroethylene powder. The aluminum powder, molybdenum trioxide powder and polytetrafluoroethylene powder has a particle size of 0.1 .mu.m or less, more preferably a particle size of from about 200-500 angstroms.

Surface enhanced Raman scattering of biospecies on anodized aluminum oxide films

NASA Astrophysics Data System (ADS)

Zhang, C.; Smirnov, A. I.; Hahn, D.; Grebel, H.

2007-06-01

Traditionally, aluminum and anodized aluminum oxide films (AAO) are not the platforms of choice for surface-enhanced raman scattering (SERS) experiments despite of the aluminum's large negative permittivity value. Here we examine the usefulness of aluminum and nanoporous alumina platforms for detecting soft biospecies ranging from bacterial spores to protein markers. We used these flat platforms to examine SERS of a model protein (cytochrome c from bovine heart tissue) and bacterial cells (spores of Bacillus subtilis ATCC13933 used as Anthrax simulant) and demonstrated clear Raman amplification.

Zirconium-based conversion film formation on zinc, aluminium and magnesium oxides and their interactions with functionalized molecules

NASA Astrophysics Data System (ADS)

Fockaert, L. I.; Taheri, P.; Abrahami, S. T.; Boelen, B.; Terryn, H.; Mol, J. M. C.

2017-11-01

Zirconium-based conversion treatment of zinc, aluminium and magnesium oxides have been studied in-situ using ATR-FTIR in a Kretschmann geometry. This set-up was coupled to an electrochemical cell, which allowed to obtain chemical and electrochemical information simultaneously as a function of conversion time. This elucidated the strong relation between physico-chemical surface properties and zirconium-based conversion kinetics. Whereas the surface hydroxyl density of zinc and aluminium increased during conversion, magnesium (hydr)oxide was shown to dissolve in the acid solution. Due to this dissolution, strong surface alkalization can be expected, explaining the rapid conversion kinetics. AES depth profiling was used to determine the final oxide thickness and elemental composition. This confirmed that magnesium is most active and forms a zirconium oxide layer approximately 10 times thicker than zinc. On the other hand, the presence of zirconium oxide on aluminium is very low and can be considered as not fully covering the metal oxide. Additionally, the converted oxide chemistry was related to the bonding mechanisms of amide functionalized molecules using ATR-FTIR and XPS. It was shown that inclusion of zirconium altered the acid-base properties, increasing the substrate proton donating capabilities in case of magnesium oxide and increasing hydrogen bonding and Bronsted interactions due to increased surface hydroxide fractions on zinc and aluminium substrates.

Selective Metallization of Well Aligned PS-b-P2VP Block Copolymers in Thin Films and in Confined Geometries

NASA Astrophysics Data System (ADS)

Sievert, James D.; Watkins, James J.; Russell, Thomas P.

2006-03-01

Well aligned, microphase-separated structures of styrene-2-vinylpyridine block copolymers are being used as templates for macromolecule-metal nanocomposites. These composites are either prepared as thin films or confined in nanoporous aluminum oxide membranes. Under optimal conditions, templates are prepared as thin films or confined nanorods and metallized without disturbing the ordered structure. We have developed a procedure that deposits metal within the polymer using supercritical carbon dioxide-soluble metal precursors. The use of supercritical carbon dioxide allows for selective metallization of the polymer at or below the glass transition, without disrupting the morphology. In addition, similar procedures have been investigated using metal salts and acids. Using these techniques, metals and metal-sulfides including silver, gold, platinum and zinc sulfide have been selectively deposited.

Formulation procedures, rationale, and preliminary IMP-H flight data for silicone paints with improved stability

NASA Technical Reports Server (NTRS)

Schutt, J. B.; Shai, C. M.

1973-01-01

Results are given of a class of silicone paints undergoing space qualification on IMP-H. In addition to ultraviolet irradiation, samples are presently reclining about 10 to the 16th power solar wind protons per year. Preliminary data, covering the time span of the first anniversary, give incremental solar absorptances of 0.03 for two white paints, and 0.01 for leafing aluminum and a green tinted white paint. Complementing these data are complete descriptions of techniques used in making these paints, stabilizing the zinc oxide pigment, and choosing a solvent. Outgassing characteristics of finished coatings are also included. An attempt toward unification of these various aspects of the aerospace paint problem is provided through documented photochemical reactions, and a generalized band representation of the problem and its solutions.

Effect of different coating layer on the topography and optical properties of ZnO nanostructured

NASA Astrophysics Data System (ADS)

Mohamed, R.; Mamat, M. H.; Malek, M. F.; Ismail, A. S.; Yusoff, M. M.; Asiah, M. N.; Khusaimi, Z.; Rusop, M.

2018-05-01

Magnesium (Mg) and aluminum (Al) co-doped zinc oxide (MAZO) thin films were synthesized on glass substrate by sol-gel spin coating method. MAZO thin films were prepared at different coating layers range from 1 to 9. Atomic Force Microscopy (AFM) was used to investigate the topography of the thin films. According to the AFM results, Root Means Square (RMS) of MAZO thin films was increased from 0.747 to 6.545 nm, with increase of number coating layer from 1 to 9, respectively. The results shown the variation on structural and topography properties of MAZO seed film when it's deposited at different coating layers on glass substrate. The optical properties was analyzed using UV-Vis spectroscopy. The obtained results show that the transmittance spectra was increased as thin films coating layer increases.

Low Plasma Zinc Is Associated with Higher Mitochondrial Oxidative Stress and Faster Liver Fibrosis Development in the Miami Adult Studies in HIV Cohort.

PubMed

Martinez, Sabrina S; Campa, Adriana; Li, Yinghui; Fleetwood, Christina; Stewart, Tiffanie; Ramamoorthy, Venkataraghavan; Baum, Marianna K

2017-04-01

Background: Oxidative stress and reduced antioxidants may be a trigger for liver fibrogenesis. Reducing oxidative stress through higher antioxidant concentration may be a potential antifibrotic target. Objective: We aimed to investigate longitudinally whether plasma zinc, an antioxidant, is related to mitochondrial oxidative stress and the progression of liver fibrosis in the Miami Adult Studies in HIV (MASH) cohort. Methods: A prospective observational cohort study was conducted in 487 predominantly African American HIV-monoinfected and HIV/hepatitis C virus (HCV)-coinfected adults with a mean ± SD age of 47.08 ± 7.67 y from the MASH cohort and followed for a median of 34 mo. Blood was collected for plasma zinc and measures were used to calculate the fibrosis-4 (FIB-4) score (aspartate amino transferase, alanine aminotransferase, and platelets). Plasma zinc deficiency was defined as <0.75 mg/L. Total DNA was extracted from peripheral blood mononuclear cells and mitochondrial DNA (mtDNA) 8-hydroxyguanosine (8-oxo-dG) was determined. Adjusted mixed models were used to assess the relations between zinc, stage of liver disease, and oxidative stress over time and compared between HIV and HIV/HCV groups. Results: Zinc concentrations (β: -0.368, SE = 0.172; P = 0.033) and deficiency were associated with lower FIB-4 scores over time (β: 0.381, SE = 0.118; P = 0.001). Compared with those who were not zinc deficient, zinc-deficient participants had an increased risk of having more-progressed liver disease (OR: 1.91; 95% CI: 1.15, 3.16; P = 0.012). Higher mtDNA 8-oxo-dG was associated with zinc deficiency (β: 0.049, SE = 0.024; P = 0.044) and higher FIB-4 scores over time (β: 0.597, SE = 0.168, P < 0.001). Conclusions: Lower plasma zinc concentrations were associated with liver fibrosis progression and mitochondrial oxidative stress in the HIV and HIV/HCV groups. Zinc may play a role in the impact of liver disease outcomes. © 2017 American Society for Nutrition.

Low Plasma Zinc Is Associated with Higher Mitochondrial Oxidative Stress and Faster Liver Fibrosis Development in the Miami Adult Studies in HIV Cohort1234

PubMed Central

Martinez, Sabrina S; Campa, Adriana; Li, Yinghui; Fleetwood, Christina; Stewart, Tiffanie; Ramamoorthy, Venkataraghavan; Baum, Marianna K

2017-01-01

Background: Oxidative stress and reduced antioxidants may be a trigger for liver fibrogenesis. Reducing oxidative stress through higher antioxidant concentration may be a potential antifibrotic target. Objective: We aimed to investigate longitudinally whether plasma zinc, an antioxidant, is related to mitochondrial oxidative stress and the progression of liver fibrosis in the Miami Adult Studies in HIV (MASH) cohort. Methods: A prospective observational cohort study was conducted in 487 predominantly African American HIV-monoinfected and HIV/hepatitis C virus (HCV)–coinfected adults with a mean ± SD age of 47.08 ± 7.67 y from the MASH cohort and followed for a median of 34 mo. Blood was collected for plasma zinc and measures were used to calculate the fibrosis-4 (FIB-4) score (aspartate amino transferase, alanine aminotransferase, and platelets). Plasma zinc deficiency was defined as <0.75 mg/L. Total DNA was extracted from peripheral blood mononuclear cells and mitochondrial DNA (mtDNA) 8-hydroxyguanosine (8-oxo-dG) was determined. Adjusted mixed models were used to assess the relations between zinc, stage of liver disease, and oxidative stress over time and compared between HIV and HIV/HCV groups. Results: Zinc concentrations (β: −0.368, SE = 0.172; P = 0.033) and deficiency were associated with lower FIB-4 scores over time (β: 0.381, SE = 0.118; P = 0.001). Compared with those who were not zinc deficient, zinc-deficient participants had an increased risk of having more-progressed liver disease (OR: 1.91; 95% CI: 1.15, 3.16; P = 0.012). Higher mtDNA 8-oxo-dG was associated with zinc deficiency (β: 0.049, SE = 0.024; P = 0.044) and higher FIB-4 scores over time (β: 0.597, SE = 0.168, P < 0.001). Conclusions: Lower plasma zinc concentrations were associated with liver fibrosis progression and mitochondrial oxidative stress in the HIV and HIV/HCV groups. Zinc may play a role in the impact of liver disease outcomes. PMID:28228506

Revisiting the Corrosion of the Aluminum Current Collector in Lithium-Ion Batteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, Tianyuan; Xu, Gui-Liang; Li, Yan

The corrosion of aluminum current collectors and the oxidation of solvents at a relatively high potential have been widely investigated with an aim to stabilize the electrochemical performance of lithium-ion batteries using such components. The corrosion behavior of aluminum current collectors was revisited using a home-build high-precision electrochemical measurement system, and the impact of electrolyte components and the surface protection layer on aluminum foil was systematically studied. The electrochemical results showed that the corrosion of aluminum foil was triggered by the electrochemical oxidation of solvent molecules, like ethylene carbonate, at a relative high potential. The organic radical cations generated frommore » the electrochemical oxidation are energetically unstable, and readily undergo a deprotonation reaction that generates protons and promote the dissolution of Al3+ from the aluminum foil. This new reaction mechanism can also shed light on the dissolution of transitional metal at high potentials.« less

Revisiting the Corrosion of the Aluminum Current Collector in Lithium-Ion Batteries

DOE PAGES

Ma, Tianyuan; Xu, Gui -Liang; Li, Yan; ...

2017-02-16

The corrosion of aluminum current collectors and the oxidation of solvents at a relatively high potential have been widely investigated with an aim to stabilize the electrochemical performance of lithium-ion batteries using such components. The corrosion behavior of aluminum current collectors was revisited using a home-build high-precision electrochemical measurement system, and the impact of electrolyte components and the surface protection layer on aluminum foil was systematically studied. The electrochemical results showed that the corrosion of aluminum foil was triggered by the electrochemical oxidation of solvent molecules, like ethylene carbonate, at a relative high potential. The organic radical cations generated frommore » the electrochemical oxidation are energetically unstable, and readily undergo a deprotonation reaction that generates protons and promote the dissolution of Al 3+ from the aluminum foil. Finally, this new reaction mechanism can also shed light on the dissolution of transitional metal at high potentials.« less

Revisiting the Corrosion of the Aluminum Current Collector in Lithium-Ion Batteries.

PubMed

Ma, Tianyuan; Xu, Gui-Liang; Li, Yan; Wang, Li; He, Xiangming; Zheng, Jianming; Liu, Jun; Engelhard, Mark H; Zapol, Peter; Curtiss, Larry A; Jorne, Jacob; Amine, Khalil; Chen, Zonghai

2017-03-02

The corrosion of aluminum current collectors and the oxidation of solvents at a relatively high potential have been widely investigated with an aim to stabilize the electrochemical performance of lithium-ion batteries using such components. The corrosion behavior of aluminum current collectors was revisited using a home-build high-precision electrochemical measurement system, and the impact of electrolyte components and the surface protection layer on aluminum foil was systematically studied. The electrochemical results showed that the corrosion of aluminum foil was triggered by the electrochemical oxidation of solvent molecules, like ethylene carbonate, at a relative high potential. The organic radical cations generated from the electrochemical oxidation are energetically unstable and readily undergo a deprotonation reaction that generates protons and promotes the dissolution of Al 3+ from the aluminum foil. This new reaction mechanism can also shed light on the dissolution of transitional metal at high potentials.

Revisiting the Corrosion of the Aluminum Current Collector in Lithium-Ion Batteries

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ma, Tianyuan; Xu, Gui -Liang; Li, Yan

The corrosion of aluminum current collectors and the oxidation of solvents at a relatively high potential have been widely investigated with an aim to stabilize the electrochemical performance of lithium-ion batteries using such components. The corrosion behavior of aluminum current collectors was revisited using a home-build high-precision electrochemical measurement system, and the impact of electrolyte components and the surface protection layer on aluminum foil was systematically studied. The electrochemical results showed that the corrosion of aluminum foil was triggered by the electrochemical oxidation of solvent molecules, like ethylene carbonate, at a relative high potential. The organic radical cations generated frommore » the electrochemical oxidation are energetically unstable, and readily undergo a deprotonation reaction that generates protons and promote the dissolution of Al 3+ from the aluminum foil. Finally, this new reaction mechanism can also shed light on the dissolution of transitional metal at high potentials.« less

Ferrous Analysis.

ERIC Educational Resources Information Center

Straub, William A.

1989-01-01

Elements covered in this review include: aluminum, antimony, arsenic, bismuth, boron, calcium, carbon, chromium, cobalt, copper, hydrogen, iron, lead, magnesium, manganese, molybdenum, nickel, niobium, nitrogen, oxygen, phosphorus, platinum, rare earths, silicons, sulfur, tin, titanium, tungsten, vanadium, zinc, and zirconium. Analytical methods…