Photochemical Copper Coating on 3D Printed Thermoplastics

NASA Astrophysics Data System (ADS)

Yung, Winco K. C.; Sun, Bo; Huang, Junfeng; Jin, Yingdi; Meng, Zhengong; Choy, Hang Shan; Cai, Zhixiang; Li, Guijun; Ho, Cheuk Lam; Yang, Jinlong; Wong, Wai Yeung

2016-08-01

3D printing using thermoplastics has become very popular in recent years, however, it is challenging to provide a metal coating on 3D objects without using specialized and expensive tools. Herein, a novel acrylic paint containing malachite for coating on 3D printed objects is introduced, which can be transformed to copper via one-step laser treatment. The malachite containing pigment can be used as a commercial acrylic paint, which can be brushed onto 3D printed objects. The material properties and photochemical transformation processes have been comprehensively studied. The underlying physics of the photochemical synthesis of copper was characterized using density functional theory calculations. After laser treatment, the surface coating of the 3D printed objects was transformed to copper, which was experimentally characterized by XRD. 3D printed prototypes, including model of the Statue of Liberty covered with a copper surface coating and a robotic hand with copper interconnections, are demonstrated using this painting method. This composite material can provide a novel solution for coating metals on 3D printed objects. The photochemical reduction analysis indicates that the copper rust in malachite form can be remotely and photo-chemically reduced to pure copper with sufficient photon energy.

Photochemical Copper Coating on 3D Printed Thermoplastics

PubMed Central

Yung, Winco K. C.; Sun, Bo; Huang, Junfeng; Jin, Yingdi; Meng, Zhengong; Choy, Hang Shan; Cai, Zhixiang; Li, Guijun; Ho, Cheuk Lam; Yang, Jinlong; Wong, Wai Yeung

2016-01-01

3D printing using thermoplastics has become very popular in recent years, however, it is challenging to provide a metal coating on 3D objects without using specialized and expensive tools. Herein, a novel acrylic paint containing malachite for coating on 3D printed objects is introduced, which can be transformed to copper via one-step laser treatment. The malachite containing pigment can be used as a commercial acrylic paint, which can be brushed onto 3D printed objects. The material properties and photochemical transformation processes have been comprehensively studied. The underlying physics of the photochemical synthesis of copper was characterized using density functional theory calculations. After laser treatment, the surface coating of the 3D printed objects was transformed to copper, which was experimentally characterized by XRD. 3D printed prototypes, including model of the Statue of Liberty covered with a copper surface coating and a robotic hand with copper interconnections, are demonstrated using this painting method. This composite material can provide a novel solution for coating metals on 3D printed objects. The photochemical reduction analysis indicates that the copper rust in malachite form can be remotely and photo-chemically reduced to pure copper with sufficient photon energy. PMID:27501761

Photochemical Copper Coating on 3D Printed Thermoplastics.

PubMed

Yung, Winco K C; Sun, Bo; Huang, Junfeng; Jin, Yingdi; Meng, Zhengong; Choy, Hang Shan; Cai, Zhixiang; Li, Guijun; Ho, Cheuk Lam; Yang, Jinlong; Wong, Wai Yeung

2016-08-09

3D printing using thermoplastics has become very popular in recent years, however, it is challenging to provide a metal coating on 3D objects without using specialized and expensive tools. Herein, a novel acrylic paint containing malachite for coating on 3D printed objects is introduced, which can be transformed to copper via one-step laser treatment. The malachite containing pigment can be used as a commercial acrylic paint, which can be brushed onto 3D printed objects. The material properties and photochemical transformation processes have been comprehensively studied. The underlying physics of the photochemical synthesis of copper was characterized using density functional theory calculations. After laser treatment, the surface coating of the 3D printed objects was transformed to copper, which was experimentally characterized by XRD. 3D printed prototypes, including model of the Statue of Liberty covered with a copper surface coating and a robotic hand with copper interconnections, are demonstrated using this painting method. This composite material can provide a novel solution for coating metals on 3D printed objects. The photochemical reduction analysis indicates that the copper rust in malachite form can be remotely and photo-chemically reduced to pure copper with sufficient photon energy.

Line focus concentrating collector for Copper Mountain Ski Resort, Colorado (Engineering Materials)

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

Not Available

1983-06-02

The present invention is a device which develops an accurate line focus concentrating collector by flexural bending of thin reflective materials. This method avoids the need for expensive tooling and support frame fabrication. The technical work conducted during this quarter included completion of designs for the prototype system for the Copper Mountain Ski Resort in Colorado. Evaluation of alternate tracking and drive systems and final design of the support system. These drawings accompany DOE/CS/15072--T4.

Test of 60 kA coated conductor cable prototypes for fusion magnets

NASA Astrophysics Data System (ADS)

Uglietti, D.; Bykovsky, N.; Sedlak, K.; Stepanov, B.; Wesche, R.; Bruzzone, P.

2015-12-01

Coated conductors could be promising materials for the fabrication of the large magnet systems of future fusion devices. Two prototype conductors (flat cables in steel conduits), each about 2 m long, were manufactured using coated conductor tapes (4 mm wide) from Super Power and SuperOx, with a total tape length of 1.6 km. Each flat cable is assembled from 20 strands, each strand consisting of a stack of 16 tapes surrounded by two half circular copper profiles, twisted and soldered. The tapes were measured at 12 T and 4.2 K and the results of the measurements were used for the assessment of the conductor electromagnetic properties at low temperature and high field. The two conductors were assembled together in a sample that was tested in the European Dipole (EDIPO) facility. The current sharing temperatures of the two conductors were measured at background fields from 8 T up to 12 T and for currents from 30 kA up to 70 kA: the measured values are within a few percent of the values expected from the measurements on tapes (short samples). After electromagnetic cycling, T cs at 12 T and 50 kA decreased from about 12 K to 11 K (about 10%), corresponding to less than 3% of I c.

Uv Spectroscopy on Gas Phase Cu(I)-BIPYRIDYL Complexes

NASA Astrophysics Data System (ADS)

Xu, Shuang; Christopher, Casey; Weber, J. Mathias

2015-06-01

Transition metal complexes with bipyridine ligands are of great interest in metal-organic chemistry, since they are prototypes for many applications in photochemistry and homogeneous catalysis. Under-coordinated bipyridyl complexes are elusive species in the condensed phase, and the ligand-induced changes in electronic structure are of fundamental interest. We present UV photodissociation spectra of mass-selected monocationic copper(I)-bipyridyl complexes [bpy-Cu-L]+ with different ligands (L = H2O, D2, N2, MeOH, Cl). Complexes were prepared via electrospray ionization of copper/bipyridine solutions followed by accumulation and buffer gas cooling in a cryogenic Paul trap. In addition, we show spectra of similar species based on copper oxide, [bpy-CuO-L]+.

Remote Stabilization of Copper Paddlewheel Based Molecular Building Blocks in Metal-Organic Frameworks

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

Gao, Wen-Yang; Cai, Rong; Pham, Tony

Copper paddlewheel based molecular building blocks (MBBs) are ubiquitous and have been widely employed for the construction of highly porous metal–organic frameworks (MOFs). However, most copper paddlewheel based MOFs fail to retain their structural integrity in the presence of water. This instability is directly correlated to the plausible displacement of coordinating carboxylates in the copper paddlewheel MBB, [Cu₂(O₂C-)₄], by the strongly coordinating water molecules. In this comprehensive study, we illustrate the chemical stability control in the rht-MOF platform via strengthening the coordinating bonds within the triangular inorganic MBB, [Cu₃O(N 4–x(CH) xC-)₃] (x = 0, 1, or 2). Remotely, the chemicalmore » stabilization propagated into the paddlewheel MBB to afford isoreticular rht-MOFs with remarkably enhanced water/chemical stabilities compared to the prototypal rht-MOF-1.« less

Additive and Photochemical Manufacturing of Copper

PubMed Central

Yung, Winco K. C.; Sun, Bo; Meng, Zhengong; Huang, Junfeng; Jin, Yingdi; Choy, Hang Shan; Cai, Zhixiang; Li, Guijun; Ho, Cheuk Lam; Yang, Jinlong; Wong, Wai Yeung

2016-01-01

In recent years, 3D printing technologies have been extensively developed, enabling rapid prototyping from a conceptual design to an actual product. However, additive manufacturing of metals in the existing technologies is still cost-intensive and time-consuming. Herein a novel platform for low-cost additive manufacturing is introduced by simultaneously combining the laser-induced forward transfer (LIFT) method with photochemical reaction. Using acrylonitrile butadiene styrene (ABS) polymer as the sacrificial layer, sufficient ejection momentum can be generated in the LIFT method. A low-cost continuous wave (CW) laser diode at 405 nm was utilized and proved to be able to transfer the photochemically synthesized copper onto the target substrate. The wavelength-dependent photochemical behaviour in the LIFT method was verified and characterized by both theoretical and experimental studies compared to 1064 nm fiber laser. The conductivity of the synthesized copper patterns could be enhanced using post electroless plating while retaining the designed pattern shapes. Prototypes of electronic circuits were accordingly built and demonstrated for powering up LEDs. Apart from pristine PDMS materials with low surface energies, the proposed method can simultaneously perform laser-induced forward transfer and photochemical synthesis of metals, starting from their metal oxide forms, onto various target substrates such as polyimide, glass and thermoplastics. PMID:28000733

Additive and Photochemical Manufacturing of Copper

NASA Astrophysics Data System (ADS)

Yung, Winco K. C.; Sun, Bo; Meng, Zhengong; Huang, Junfeng; Jin, Yingdi; Choy, Hang Shan; Cai, Zhixiang; Li, Guijun; Ho, Cheuk Lam; Yang, Jinlong; Wong, Wai Yeung

2016-12-01

In recent years, 3D printing technologies have been extensively developed, enabling rapid prototyping from a conceptual design to an actual product. However, additive manufacturing of metals in the existing technologies is still cost-intensive and time-consuming. Herein a novel platform for low-cost additive manufacturing is introduced by simultaneously combining the laser-induced forward transfer (LIFT) method with photochemical reaction. Using acrylonitrile butadiene styrene (ABS) polymer as the sacrificial layer, sufficient ejection momentum can be generated in the LIFT method. A low-cost continuous wave (CW) laser diode at 405 nm was utilized and proved to be able to transfer the photochemically synthesized copper onto the target substrate. The wavelength-dependent photochemical behaviour in the LIFT method was verified and characterized by both theoretical and experimental studies compared to 1064 nm fiber laser. The conductivity of the synthesized copper patterns could be enhanced using post electroless plating while retaining the designed pattern shapes. Prototypes of electronic circuits were accordingly built and demonstrated for powering up LEDs. Apart from pristine PDMS materials with low surface energies, the proposed method can simultaneously perform laser-induced forward transfer and photochemical synthesis of metals, starting from their metal oxide forms, onto various target substrates such as polyimide, glass and thermoplastics.

Neutron measurements from beam-target reactions at the ELISE neutral beam test facility

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

Xufei, X., E-mail: xiexufei@pku.edu.cn; Fan, T.; Nocente, M.

2014-11-15

Measurements of 2.5 MeV neutron emission from beam-target reactions performed at the ELISE neutral beam test facility are presented in this paper. The measurements are used to study the penetration of a deuterium beam in a copper dump, based on the observation of the time evolution of the neutron counting rate from beam-target reactions with a liquid scintillation detector. A calculation based on a local mixing model of deuterium deposition in the target up to a concentration of 20% at saturation is used to evaluate the expected neutron yield for comparison with data. The results are of relevance to understandmore » neutron emission associated to beam penetration in a solid target, with applications to diagnostic systems for the SPIDER and MITICA Neutral Beam Injection prototypes.« less

In situ antimicrobial behavior of materials with copper-based additives in a hospital environment.

PubMed

Palza, Humberto; Nuñez, Mauricio; Bastías, Roberto; Delgado, Katherine

2018-06-01

Copper and its alloys are effective antimicrobial surface materials in the laboratory and in clinical trials. Copper has been used in the healthcare setting to reduce environmental contamination, and thus prevent healthcare-associated infections, complementing traditional protocols. The addition of copper nanoparticles to polymer/plastic matrices can also produce antimicrobial materials, as confirmed under laboratory conditions. However, there is a lack of studies validating the antimicrobial effects of these nanocomposite materials in clinical trials. To satisfy this issue, plastic waiting room chairs with embedded metal copper nanoparticles, and metal hospital IV pools coated with an organic paint with nanostructured zeolite/copper particles were produced and tested in a hospital environment. These prototypes were sampled once weekly for 10 weeks and the viable microorganisms were analysed and compared with the copper-free materials. In the waiting rooms, chairs with copper reduced by around 73% the total viable microorganisms present, showing activity regardless of the microorganism tested. Although there were only low levels of microorganisms in the IV pools installed in operating rooms because of rigorous hygiene protocols, samples with copper presented lower total viable microorganisms than unfilled materials. Some results did not have statistical significance because of the low load of microorganisms; however, during at least three weeks the IV pools with copper had reduced levels of microorganisms by a statistically significant 50%. These findings show for the first time the feasibility of utilizing the antimicrobial property of copper by adding nanosized fillers to other materials in a hospital environment. Copyright © 2018 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

Ferrite HOM Absorber for the RHIC ERL

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

Hahn,H.; Choi, E.M.; Hammons, L.

A superconducting Energy Recovery Linac is under construction at Brookhaven National Laboratory to serve as test bed for RHIC upgrades. The damping of higher-order modes in the superconducting five-cell cavity for the Energy-Recovery linac at RHIC is performed exclusively by two ferrite absorbers. The ferrite properties have been measured in ferrite-loaded pill box cavities resulting in the permeability values given by a first-order Debye model for the tiled absorber structure and an equivalent permeability value for computer simulations with solid ring dampers. Measured and simulated results for the higher-order modes in the prototype copper cavity are discussed. First room-temperature measurementsmore » of the finished niobium cavity are presented which confirm the effective damping of higher-order modes in the ERL. by the ferrite absorbers.« less

WE-DE-BRA-06: Evaluation of the Imaging Performance of a Novel Water-Equivalent EPID

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

Blake, SJ; The Ingham Institute, Liverpool, NSW; Cheng, J

Purpose: To evaluate the megavoltage imaging performance of a novel, water-equivalent electronic portal imaging device (EPID) developed for simultaneous imaging and dosimetry applications in radiotherapy. Methods: A novel EPID prototype based on active matrix flat panel imager technology has been developed by our group and previously reported to exhibit a water-equivalent dose response. It was constructed by replacing all components above the photodiode detector in a standard clinical EPID (including the copper plate and phosphor screen) with a 15 × 15 cm{sup 2} array of plastic scintillator fibers. Individual fibers measured 0.5 × 0.5 × 30 mm{sup 3}. Spatial resolutionmore » was evaluated experimentally relative to that of a standard EPID with the thin slit technique to measure the modulation transfer function (MTF) for 6 MV x-ray beams. Monte Carlo (MC) EPID models were used to benchmark simulated MTFs against the measurements. The zero spatial frequency detective quantum efficiency (DQE(0)) was simulated for both EPID configurations and a preliminary optimization of the prototype was performed by evaluating DQE(0) as a function of fiber length up to 50 mm. Results: The MC-simulated DQE(0) for the prototype EPID configuration was ∼7 times greater than that of the standard EPID. The prototype’s DQE(0) also increased approximately linearly with fiber length, from ∼1% at 5 mm length to ∼11% at 50 mm length. The standard EPID MTF was greater than the prototype EPID’s for all spatial frequencies, reflecting the trade off between x-ray detection efficiency and spatial resolution with thick scintillators. Conclusion: This study offers promising evidence that a water-equivalent EPID previously demonstrated for radiotherapy dosimetry may also be used for radiotherapy imaging applications. Future studies on optimising the detector design will be performed to develop a next-generation prototype that offers improved megavoltage imaging performance, with the aim to at least match that of current clinical EPIDs. Funding for this project was provided by an Australian Research Council Linkage Project grant (2015) between The University of Sydney, South Western Sydney Local Health District and Perkin-Elmer Pty Ltd.« less

Phase-compensated metasurface for a conformal microwave antenna

NASA Astrophysics Data System (ADS)

Germain, Dylan; Seetharamdoo, Divitha; Nawaz Burokur, Shah; de Lustrac, André

2013-09-01

The in-phase radiation from a conformal metamaterial surface is numerically and experimentally reported. The LC-resonant metasurface is composed of a simultaneously capacitive and an inductive grid constituted by copper strips printed on both sides of a dielectric board. The metasurface is designed to fit a curved surface by modifying its local phase. The latter phase-compensated metasurface is used as a reflector in a conformal Fabry-Pérot resonant cavity designed to operate at microwave frequencies. Far-field measurements performed on a fabricated prototype allow showing the good performances of such a phase-compensated metasurface in restoring in-phase emissions from the conformal surface and producing a directive emission in the desired direction.

Design development and construction of the RFX field shaping winding

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

Chitarin, G.; Guarnieri, M.; Stella, A.

1989-03-01

The paper describes the development work on the design and the manufacture of the RFX Field Shaping Winding, from the preliminary analysis and the tests on prototypes to the final design. The winding consists of 16 coils, with 24 copper turns each and of diameters up to 5.5 m. The maximum current is 6.25 kA and the maximum voltage to earth is 35 kV. Each coil is supported in 24 radial locations and the electrodynamic load on a single coil is approximately 40 kN/m in normal operation. Fiberglass impregnated with epoxy resin, reinforced in places with polymide tape, has beenmore » used for the insulation. The high levels of the electrical and mechanical strength specified present conflicting constraints, which have required some care in the structural design and the definition of insulation system and impregnation technology. Although the use of copper coils with this kid of insulation may seem obvious and well established, indeed the stringent operational requirements have posed a number of problems which have demanded extensive work on the design and prototype development.« less

Kilopixel X-Ray Microcalorimeter Arrays for Astrophysics: Device Performance and Uniformity

NASA Technical Reports Server (NTRS)

Eckart, M. E.; Adams, J. S.; Bailey, C. N.; Bandler, S. R.; Busch, S. E.; Chervenak, J. A.; Finkbeiner, F. M.; Kelley, R. L.; Kilbourne, C. A.; Porter, F. S.;

Polarization Control via He-Ion Beam Induced Nanofabrication in Layered Ferroelectric Semiconductors

DOE PAGES

Belianinov, Alex; Iberi, Vighter; Tselev, Alexander; ...

2016-02-23

Rapid advanced in nanoscience rely on continuous improvements of matter manipulation at near atomic scales. Currently, well characterized, robust, resist-based lithography carries the brunt of the nanofabrication process. However, use of local electron, ion and physical probe methods is also expanding, driven largely by their ability to fabricate without the multi-step preparation processes that can result in contamination from resists and solvents. Furthermore, probe based methods extend beyond nanofabrication to nanomanipulation and imaging, vital ingredients to rapid transition to prototyping and testing of layered 2D heterostructured devices. In this work we demonstrate that helium ion interaction, in a Helium Ionmore » Microscope (HIM), with the surface of bulk copper indium thiophosphate CuM IIIP 2X 6 (M = Cr, In; X= S, Se), (CITP) results in the control of ferroelectric domains, and growth of cylindrical nanostructures with enhanced conductivity; with material volumes scaling with the dosage of the beam. The nanostructures are oxygen rich, sulfur poor, and with the copper concentration virtually unchanged as confirmed by Energy Dispersive X-ray (EDX). Scanning Electron Microscopy (SEM) imaging contrast as well as Scanning Microwave Microscopy (SMM) measurements suggest enhanced conductivity in the formed particle, whereas Atomic Force Microscopy (AFM) measurements indicate that the produced structures have lower dissipation and a lower Young s modulus.« less

POLOCAM: a millimeter wavelength cryogenic polarimeter prototype for MUSIC-POL

NASA Astrophysics Data System (ADS)

Laurent, Glenn T.; Vaillancourt, John E.; Savini, Giorgio; Ade, Peter A. R.; Beland, Stephane; Glenn, Jason; Hollister, Matthew I.; Maloney, Philip R.; Sayers, Jack

2012-09-01

As a proof-of-concept, we have constructed and tested a cryogenic polarimeter in the laboratory as a prototype for the MUSIC instrument (Multiwavelength Sub/millimeter Kinetic Inductance Camera). The POLOCAM instrument consists of a rotating cryogenic polarization modulator (sapphire half-waveplate) and polarization analyzer (lithographed copper polarizers deposited on a thin film) placed into the optical path at the Lyot stop (4K cold pupil stop) in a cryogenic dewar. We present an overview of the project, design and performance results of the POLOCAM instrument (including polarization efficiencies and instrumental polarization), as well as future application to the MUSIC-POL instrument.

Polarimetric performance of a Laue lens gamma-ray CdZnTe focal plane prototype

NASA Astrophysics Data System (ADS)

Curado da Silva, R. M.; Caroli, E.; Stephen, J. B.; Pisa, A.; Auricchio, N.; Del Sordo, S.; Frontera, F.; Honkimäki, V.; Schiavone, F.; Donati, A.; Trindade, A. M. F.; Ventura, G.

2008-10-01

A gamma-ray telescope mission concept [gamma ray imager (GRI)] based on Laue focusing techniques has been proposed in reply to the European Space Agency call for mission ideas within the framework of the next decade planning (Cosmic Vision 2015-2025). In order to optimize the design of a focal plane for this satellite mission, a CdZnTe detector prototype has been tested at the European Synchrotron Radiation Facility under an ~100% polarized gamma-ray beam. The spectroscopic, imaging, and timing performances were studied and in particular its potential as a polarimeter was evaluated. Polarization has been recognized as being a very important observational parameter in high energy astrophysics (>100 keV) and therefore this capability has been specifically included as part of the GRI mission proposal. The prototype detector tested was a 5 mm thick CdZnTe array with an 11×11 active pixel matrix (pixel area of 2.5×2.5 mm2). The detector was irradiated by a monochromatic linearly polarized beam with a spot diameter of about 0.5 mm over the energy range between 150 and 750 keV. Polarimetric Q factors of 0.35 and double event relative detection efficiency of 20% were obtained. Further measurements were performed with a copper Laue monochromator crystal placed between the beam and the detector prototype. In this configuration we have demonstrated that a polarized beam does not change its polarization level and direction after undergoing a small angle (<1°) Laue diffraction inside a crystal.

Negative ion beam characterisation in BATMAN by mini-STRIKE: Improved design and new measurements

NASA Astrophysics Data System (ADS)

Serianni, G.; Bonomo, F.; Brombin, M.; Cervaro, V.; Chitarin, G.; Cristofaro, S.; Delogu, R.; De Muri, M.; Fasolo, D.; Fonnesu, N.; Franchin, L.; Franzen, P.; Ghiraldelli, R.; Molon, F.; Muraro, A.; Pasqualotto, R.; Ruf, B.; Schiesko, L.; Tollin, M.; Veltri, P.

2015-04-01

The ITER project requires additional heating provided by two injectors of neutral beams resulting from the neutralisation of accelerated negative ions. To study and optimise negative ion production, the SPIDER test facility (particle energy 100keV; beam current 50A) is under construction in Padova, with the aim of testing beam characteristics and to verify the source proper operation. The SPIDER beam will be characterised by the instrumented calorimeter STRIKE, whose main components are one-directional carbon fibre carbon composite tiles. Some prototype tiles have been employed in 2012 as a small-scale version (mini-STRIKE) of the entire system to investigate the features of the beam from BATMAN at IPP-Garching. As the BATMAN beamlets are superposed at the measurement position, about 1m from the grounded grid, an actively cooled copper mask is located in front of the tiles; holes in the mask create an artificial beamlet structure. Recently the mini-STRIKE has been updated, taking into account the results obtained in the first campaign. In particular the spatial resolution of the system has been improved by increasing the number of the copper mask holes. Moreover a custom measurement system has been realized for the thermocouple signals and employed in BATMAN in view of its use in SPIDER. The present contribution gives a description of the new design of the system as well as of the thermocouple measurements system and its field test. A new series of measurements has been carried out in BATMAN. The BATMAN beam characterisation in different experimental conditions is presented.

Negative ion beam characterisation in BATMAN by mini-STRIKE: Improved design and new measurements

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

Serianni, G., E-mail: gianluigi.serianni@igi.cnr.it; Brombin, M.; Cervaro, V.

The ITER project requires additional heating provided by two injectors of neutral beams resulting from the neutralisation of accelerated negative ions. To study and optimise negative ion production, the SPIDER test facility (particle energy 100keV; beam current 50A) is under construction in Padova, with the aim of testing beam characteristics and to verify the source proper operation. The SPIDER beam will be characterised by the instrumented calorimeter STRIKE, whose main components are one-directional carbon fibre carbon composite tiles. Some prototype tiles have been employed in 2012 as a small-scale version (mini-STRIKE) of the entire system to investigate the features ofmore » the beam from BATMAN at IPP-Garching. As the BATMAN beamlets are superposed at the measurement position, about 1m from the grounded grid, an actively cooled copper mask is located in front of the tiles; holes in the mask create an artificial beamlet structure. Recently the mini-STRIKE has been updated, taking into account the results obtained in the first campaign. In particular the spatial resolution of the system has been improved by increasing the number of the copper mask holes. Moreover a custom measurement system has been realized for the thermocouple signals and employed in BATMAN in view of its use in SPIDER. The present contribution gives a description of the new design of the system as well as of the thermocouple measurements system and its field test. A new series of measurements has been carried out in BATMAN. The BATMAN beam characterisation in different experimental conditions is presented.« less

Large-area copper indium diselenide (CIS) process, control and manufacturing

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

Gillespie, T.J.; Lanning, B.R.; Marshall, C.H.

1997-12-31

Lockheed Martin Astronautics (LMA) has developed a large-area (30x30cm) sequential CIS manufacturing approach amenable to low-cost photovoltaics (PV) production. A prototype CIS manufacturing system has been designed and built with compositional uniformity (Cu/In ratio) verified within {+-}4 atomic percent over the 30x30cm area. CIS device efficiencies have been measured by the National Renewable Energy Laboratory (NREL) at 7% on a flexible non-sodium-containing substrate and 10% on a soda-lime-silica (SLS) glass substrate. Critical elements of the manufacturing capability include the CIS sequential process selection, uniform large-area material deposition, and in-situ process control. Details of the process and large-area manufacturing approach aremore » discussed and results presented.« less

Improved electroacoustic dewatering (EAD) belt press for food products. Phase 3, Technical progress report

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

Not Available

1994-02-01

Battelle`s electroacoustic dewatering (EAD) process improves the performance of mechanical dewatering processes for several food products (such as corn fiber) by superimposing electric and ultrasonic fields. EAD has the potential to save 0.027 to 0.035 quad/yr energy by 1995 in the food processing industry, which consumed 0.15 to 0.18 quad in 1986. This report covers Phase III for demonstrating the EAD prototype on corn wet milling products (corn fiber and gluten); only Task 1 (prototype preparation and planning) was completed. EAD performance was examined in the laboratory; availability of a test site was examined. The single-roll, postdewatering EAD belt pressmore » prototype can accept material predewatered by a screw press, centrifuge, or any other mechanical dewatering device. The two-belt system, utilizing a copper-polymer cathode belt, performed as well as the three-belt system used in Phase II.« less

Design and prototype fabrication of a 30 tesla cryogenic magnet

NASA Technical Reports Server (NTRS)

Prok, G. M.; Swanson, M. C.; Brown, G. V.

1977-01-01

A liquid neon cooled magnet was designed to produce 30 teslas in steady operation. To ensure the correctness of the heat transfer relationships used, supercritical neon heat transfer tests were made. Other tests made before the final design included tests on the effect of the magnetic field on pump motors, tensile shear tests on the cryogenic adhesives, and simulated flow studies for the coolant. The magnet will consist of two pairs of coils, cooled by forced convection of supercritical neon. Heat from the supercritical neon will be rejected through heat exchangers which are made of roll bonded copper panels and are submerged in a pool of saturated liquid neon. A partial mock up coil was wound to identify the tooling required to wind the magnet. This was followed by winding a prototype pair of coils. The prototype winding established procedures for fabricating the final magnet and revealed slight changes needed in the final design.

NiAl Coatings Investigated for Use in Reusable Launch Vehicles

NASA Technical Reports Server (NTRS)

Raj, Sai V.; Ghosn, Louis J.; Barrett, Charles A.

2003-01-01

As part of its major investment in the area of advanced space transportation, NASA is developing new technologies for use in the second- and third-generation designs of reusable launch vehicles. Among the prototype rocket engines being considered for these launch vehicles are those designed to use liquid hydrogen as the fuel and liquid oxygen as the oxidizer. Advanced copper alloys, such as copper-chromium-niobium (Cu-8(at.%)Cr- 4(at.%)Nb, also referred to as GRCop-84), which was invented at the NASA Glenn Research Center, are being considered for use as liner materials in the combustion chambers and nozzle ramps of these engines. However, previous experience has shown that, in rocket engines using liquid hydrogen and liquid oxygen, copper alloys are subject to a process called blanching, where the material undergoes environmental attack under the action of the combustion gases. In addition, the copper alloy liners undergo thermomechanical fatigue, which often results in an initially square cooling channel deforming into a dog-house shape. Clearly, there is an urgent need to develop new coatings to protect copper liners from environmental attack inside rocket chambers and to lower the temperature of the liners to reduce the probability of deformation and failure by thermomechanical fatigue.

Development of a Standard Platinum Resistance Thermometer for Use up to the Copper Point

NASA Astrophysics Data System (ADS)

Tavener, J. P.

2015-08-01

The international temperature scale of 1990 defines temperatures in the range from 13.8 K to 1234.93 K () using a standard platinum resistance thermometer (SPRT) as an interpolating instrument. For temperatures above , the current designs of an SPRT require extreme care to avoid contamination, especially by metallic impurities, which can cause rapid and irreversible drift. This study investigates the performance of a new design of a high-temperature SPRT with the aim of improving the stability of the SPRTs and extending their temperature range. The prototype SPRTs have an alumina sheath, a sapphire support for the sensing element, which are aspirated with dry air and operated with a dc bias voltage to suppress the diffusion of metal-ion contaminants. Three prototype thermometers were exposed to temperatures near or above the copper freezing point, , for total exposure times in excess of 500 h and exhibited drifts in the triple-point resistance of less than 10 mK. The new design eliminates some of the problems associated with fused-silica sheaths and sensor-support structures and is a viable option for a high-accuracy thermometer for temperatures approaching.

Multi-dimensional modeling of atmospheric copper-sulfidation corrosion on non-planar substrates.

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

Chen, Ken Shuang

2004-11-01

This report documents the author's efforts in the deterministic modeling of copper-sulfidation corrosion on non-planar substrates such as diodes and electrical connectors. A new framework based on Goma was developed for multi-dimensional modeling of atmospheric copper-sulfidation corrosion on non-planar substrates. In this framework, the moving sulfidation front is explicitly tracked by treating the finite-element mesh as a pseudo solid with an arbitrary Lagrangian-Eulerian formulation and repeatedly performing re-meshing using CUBIT and re-mapping using MAPVAR. Three one-dimensional studies were performed for verifying the framework in asymptotic regimes. Limited model validation was also carried out by comparing computed copper-sulfide thickness with experimentalmore » data. The framework was first demonstrated in modeling one-dimensional copper sulfidation with charge separation. It was found that both the thickness of the space-charge layers and the electrical potential at the sulfidation surface decrease rapidly as the Cu{sub 2}S layer thickens initially but eventually reach equilibrium values as Cu{sub 2}S layer becomes sufficiently thick; it was also found that electroneutrality is a reasonable approximation and that the electro-migration flux may be estimated by using the equilibrium potential difference between the sulfidation and annihilation surfaces when the Cu{sub 2}S layer is sufficiently thick. The framework was then employed to model copper sulfidation in the solid-state-diffusion controlled regime (i.e. stage II sulfidation) on a prototypical diode until a continuous Cu{sub 2}S film was formed on the diode surface. The framework was also applied to model copper sulfidation on an intermittent electrical contact between a gold-plated copper pin and gold-plated copper pad; the presence of Cu{sub 2}S was found to raise the effective electrical resistance drastically. Lastly, future research needs in modeling atmospheric copper sulfidation are discussed.« less

Experience of 12 kA / 16 V SMPS during the HTS Current Leads Test

NASA Astrophysics Data System (ADS)

Panchal, P.; Christian, D.; Panchal, R.; Sonara, D.; Purwar, G.; Garg, A.; Nimavat, H.; Singh, G.; Patel, J.; Tanna, V.; Pradhan, S.

2017-04-01

As a part of up gradation plans in SST-1 Tokamak, one pair of 3.3 kA rated prototype hybrid current leads were developed using Di-BSCCO as High Temperature Superconductors (HTS) and the copper heat exchanger. In order to validate the manufacturing procedure prior to go for series production of such current leads, it was recommended to test these current leads using dedicated and very reliable DC switch mode power supply (SMPS). As part of test facility, 12 kA, 16 VDC programmable SMPS was successfully installed, commissioned and tested. This power supply has special features such as modularity, N+1 redundancy, very low ripple voltage, precise current measurements with Direct Current Current Transformer, CC/CV modes with auto-crossover and auto-sequence programming. As a part of acceptance of this converter, A 5.8 mΩ water-cooled resistive dummy load and PLC based SCADA system is designed, developed for commissioning of power supply. The same power supply was used for the testing of the prototype HTS current leads. The paper describes the salient features and experience of state-of-art of power supply and results obtained from this converter during the HTS current leads test.

Dynamic "Scanning-Mode" Meniscus Confined Electrodepositing and Micropatterning of Individually Addressable Ultraconductive Copper Line Arrays.

PubMed

Lei, Yu; Zhang, Xianyun; Xu, Dingding; Yu, Minfeng; Yi, Zhiran; Li, Zhixiang; Sun, Aihua; Xu, Gaojie; Cui, Ping; Guo, Jianjun

2018-05-03

Micro- and nanopatterning of cost-effective addressable metallic nanostructures has been a long endeavor in terms of both scientific understanding and industrial needs. Herein, a simple and efficient dynamic meniscus-confined electrodeposition (MCED) technique for precisely positioned copper line micropatterns with superior electrical conductivity (greater than 1.57 × 10 4 S/cm) on glass, silicon, and gold substrates is reported. An unexpected higher printing speed in the evaporative regime is realized for precisely positioned copper lines patterns with uniform width and height under horizontal scanning-mode. The final line height and width depend on the typical behavior of traditional flow coating process, while the surface morphologies and roughness are mainly governed by evaporation-driven electrocrystallization dynamics near the receding moving contact line. Integrated 3D structures and a rapid prototyping of 3D hot-wire anemometer are further demonstrated, which is very important for the freedom integration applications in advanced conceptual devices, such as miniaturized electronics and biomedical sensors and actuators.

Electromagnetic crystal based terahertz thermal radiators and components

NASA Astrophysics Data System (ADS)

Wu, Ziran

This dissertation presents the investigation of thermal radiation from three-dimensional electromagnetic crystals (EMXT), as well as the development of a THz rapid prototyping fabrication technique and its application in THz EMXT components and micro-system fabrication and integration. First, it is proposed that thermal radiation from a 3-D EMXT would be greatly enhanced at the band gap edge frequency due to the redistribution of photon density of states (DOS) within the crystal. A THz thermal radiator could thus be built upon a THz EMXT by utilizing the exceptional emission peak(s) around its band gap frequency. The thermal radiation enhancement effects of various THz EMXT including both silicon and tungsten woodpile structures (WPS) and cubic photonic cavity (CPC) array are explored. The DOS of all three structures are calculated, and their thermal radiation intensities are predicted using Planck's Equation. These calculations show that the DOS of the silicon and tungsten WPS can be enhanced by a factor of 11.8 around 364 GHz and 2.6 around 406 GHz respectively, in comparison to the normal blackbody radiation at same frequencies. An enhancement factor of more than 100 is obtained in calculation from the CPC array. A silicon WPS with a band gap around 200 GHz has been designed and fabricated. Thermal emissivity of the silicon WPS sample is measured with a control blackbody as reference. And enhancements of the emission from the WPS over the control blackbody are observed at several frequencies quite consistent with the theoretical predictions. Second, the practical challenge of THz EMXT component and system fabrication is met by a THz rapid prototyping technique developed by us. Using this technique, the fabrications of several EMXTs with 3D electromagnetic band gaps in the 100-400 GHz range are demonstrated. Characterization of the samples via THz Time-domain Spectroscopy (THz-TDS) shows very good agreement with simulation, confirming the build accuracy of this prototyping approach. Third, an all-dielectric THz waveguide is designed, fabricated and characterized. The design is based on hollow-core EMXT waveguide, and the fabrication is implemented with the THz prototyping method. Characterization results of the waveguide power loss factor show good consistency with the simulation, and waveguide propagation loss as low as 0.03 dB/mm at 105 GHz is demonstrated. Several design parameters are also varied and their impacts on the waveguide performance investigated theoretically. Finally, a THz EMXT antenna based on expanding the defect radius of the EMXT waveguide to a horn shape is proposed and studied. The boresight directivity and main beam angular width of the optimized EMXT horn antenna is comparable with a copper horn antenna of the same dimensions at low frequencies, and much better than the copper horn at high frequencies. The EMXT antenna has been successfully fabricated via the same THz prototyping, and we believe this is the first time an EMXT antenna of this architecture is fabricated. Far-field measurement of the EMXT antenna radiation pattern is undergoing. Also, in order to integrate planar THz solid-state devices (especially source and detector) and THz samples under test with the potential THz micro-system fabricate-able by the prototyping approach, an EMXT waveguide-to-microstrip line transition structure is designed. The structure uses tapered solid dielectric waveguides on both ends to transit THz energy from the EMXT waveguide defect onto the microstrip line. Simulation of the transition structure in a back-to-back configuration yields about -15 dB insertion loss mainly due to the dielectric material loss. The coupling and radiation loss of the transition structure is estimated to be -2.115 dB. The fabrication and characterization of the transition system is currently underway. With all the above THz components realized in the future, integrated THz micro-systems manufactured by the same prototyping technique will be achieved, with low cost, high quality, self-sufficiency, and great customizability.

Performance and results of the LBNE 35 ton membrane cryostat prototype

DOE PAGES

Montanari, David; Adamowski, Mark; Hahn, Alan; ...

2015-07-15

We report on the performance and commissioning of the first membrane cryostat to be used for scientific application. The Long Baseline Neutrino Experiment (LBNE) has designed and fabricated a membrane cryostat prototype in collaboration with Ishikawajima-Harima Heavy Industries Co., Ltd. (IHI). LBNE has designed and fabricated the supporting cryogenic system infrastructure and successfully commissioned and operated the first membrane cryostat. Original goals of the prototype are: to demonstrate the membrane cryostat technology in terms of thermal performance, feasibility for liquid argon and leak tightness; to demonstrate that we can remove all the impurities from the vessel and achieve the puritymore » requirements in a membrane cryostat without evacuation; to demonstrate that we can achieve and maintain the purity requirements of the liquid argon using mol sieve and copper filters. The purity requirements of a large liquid argon detector such as LBNE are contaminants below 200 parts per trillion (ppt) oxygen equivalent. LBNE is planning the design and construction of a large liquid argon detector. This presentation will present requirements, design and construction of the LBNE 35 ton membrane cryostat prototype, and detail the commissioning and performance. The experience and results of this prototype are extremely important for the development of the LBNE detector.« less

Development of Prototype Production ESR Facilities

DTIC Science & Technology

1977-07-01

CJISTHIBUTION STATEMENT (ot (he aUxIr&cl entnred in lil^ck 21), If ctlfferert from Wfv.rtj 18. SiJPPi EMENTARV NOTES M9. Kfc y WORDS...Unlike in conventional foundry methods, electroslag castings are made in water-cooled metal molds by remelting of consumable electrodes in... CONSUMABLE ELECTRODE TOP MOLD SLAQ POOL MOLTEN METAL POOL LEVEL DETECTOR MOLTEN METAL POOL ESP INCrOT COPPER LINER mTER JACKET

Twin-Axial Wire Antenna

DTIC Science & Technology

2015-08-06

12 and 14 can be of differing gauges and can be either stranded or solid. In a prototype, both conductors were made from #22 solid copper wire ...08-2015 Publication Twin-Axial Wire Antenna David A. Tonn Naval Under Warfare Center Division, Newport 1176 Howell St., Code 00L, Bldg 102T...Approved for Public Release Distribution is unlimited Attorney Docket No. 300030 1 of 10 TWIN-AXIAL WIRE ANTENNA STATEMENT OF GOVERNMENT INTEREST

Experiment study on an inductive superconducting fault current limiter using no-insulation coils

NASA Astrophysics Data System (ADS)

Qiu, D.; Li, Z. Y.; Gu, F.; Huang, Z.; Zhao, A.; Hu, D.; Wei, B. G.; Huang, H.; Hong, Z.; Ryu, K.; Jin, Z.

2018-03-01

No-insulation (NI) coil made of 2 G high temperature superconducting (HTS) tapes has been widely used in DC magnet due to its excellent performance of engineering current density, thermal stability and mechanical strength. However, there are few AC power device using NI coil at present. In this paper, the NI coil is firstly applied into inductive superconducting fault current limiter (iSFCL). A two-winding structure air-core iSFCL prototype was fabricated, composed of a primary copper winding and a secondary no-insulation winding using 2 G HTS coated conductors. Firstly, in order to testify the feasibility to use NI coil as the secondary winding, the impedance variation of the prototype at different currents and different cycles was tested. The result shows that the impedance increases rapidly with the current rises. Then the iSFCL prototype was tested in a 40 V rms/ 3.3 kA peak short circuit experiment platform, both of the fault current limiting and recovery property of the iSFCL are discussed.

Design and prototype fabrication of a 30 tesla cryogenic magnet

NASA Technical Reports Server (NTRS)

Prok, G. M.; Swanson, M. C.; Brown, G. V.

1977-01-01

A liquid-neon-cooled magnet has been designed to produce 30 teslas in steady operation. Its feasibility was established by a previously reported parametric study. To ensure the correctness of the heat transfer relationships used, supercritical neon heat transfer tests were made. Other tests made before the final design included tests on the effect of the magnetic field on pump motors; tensile-shear tests on the cryogenic adhesives; and simulated flow studies for the coolant. The magnet will be made of two pairs of coils, cooled by forced convection of supercritical neon. Heat from the supercritical neon will be rejected through heat exchangers which are made of roll-bonded copper panels and are submerged in a pool of saturated liquid neon. A partial mock-up coil was wound to identify the tooling required to wind the magnet. This was followed by winding a prototype pair of coils. The prototype winding established procedures for fabricating the final magnet and revealed slight changes needed in the final design.

Metallographic autopsies of full-scale ITER prototype cable-in-conduit conductors after full testing in SULTAN: 1. The mechanical role of copper strands in a CICC

DOE PAGES

Sanabria, Carlos; Lee, Peter J.; Starch, William; ...

2015-06-22

Cables made with Nb 3Sn-based superconductor strands will provide the 13 T maximum peak magnetic field of the ITER Central Solenoid (CS) coils and they must survive up to 60,000 electromagnetic cycles. Accordingly, prototype designs of CS cable-in-conduit-conductors (CICC) were electromagnetically tested over multiple magnetic field cycles and warm-up-cool-down scenarios in the SULTAN facility at CRPP. We report here a post mortem metallographic analysis of two CS CICC prototypes which exhibited some rate of irreversible performance degradation during cycling. The standard ITER CS CICC cable design uses a combination of superconducting and Cu strands, and because the Lorentz force onmore » the strand is proportional to the transport current in the strand, removing the copper strands (while increasing the Cu:SC ratio of the superconducting strands) was proposed as one way of reducing the strand load. In this study we compare the two alternative CICCs, with and without Cu strands, keeping in mind that the degradation after SULTAN test was lower for the CICC without Cu strands. The post mortem metallographic evaluation revealed that the overall strand transverse movement was 20% lower in the CICC without Cu strands and that the tensile filament fractures found were less, both indications of an overall reduction in high tensile strain regions. Furthermore, it was interesting to see that the Cu strands in the mixed cable design (with higher degradation) helped reduce the contact stresses on the high pressure side of the CICC, but in either case, the strain reduction mechanisms were not enough to suppress cyclic degradation. Advantages and disadvantages of each conductor design are discussed here aimed to understand the sources of the degradation.« less

Development of x-ray laminography under an x-ray microscopic condition

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

Hoshino, Masato; Uesugi, Kentaro; Takeuchi, Akihisa

2011-07-15

An x-ray laminography system under an x-ray microscopic condition was developed to obtain a three-dimensional structure of laterally-extended planar objects which were difficult to observe by x-ray tomography. An x-ray laminography technique was introduced to an x-ray transmission microscope with zone plate optics. Three prototype sample holders were evaluated for x-ray imaging laminography. Layered copper grid sheets were imaged as a laminated sample. Diatomite powder on a silicon nitride membrane was measured to confirm the applicability of this method to non-planar micro-specimens placed on the membrane. The three-dimensional information of diatom shells on the membrane was obtained at a spatialmore » resolution of sub-micron. Images of biological cells on the membrane were also obtained by using a Zernike phase contrast technique.« less

Timing and charge measurement of single gap resistive plate chamber detectors for INO-ICAL experiment

NASA Astrophysics Data System (ADS)

Gaur, Ankit; Kumar, Ashok; Naimuddin, Md.

2018-01-01

The recently approved India-based Neutrino Observatory will use the world's largest magnet to study atmospheric muon neutrinos. The 50 kiloton Iron Calorimeter consists of iron alternating with single-gap resistive plate chambers. A uniform magnetic field of ∼1.5 T is produced in the iron using toroidal-shaped copper coils. Muon neutrinos interact with the iron target to produce charged muons, which are detected by the resistive plate chambers, and tracked using orthogonal pick up strips. Timing information for each layer is used to discriminate between upward and downward traveling muons. The design of the readout electronics for the detector depends critically on an accurate model of the charge induced by the muons, and the dependence on bias voltages. In this paper, we present timing and charge response measurements using prototype detectors under different operating conditions. We also report the effect of varying gas mixture, particularly SF6, on the timing response.

Storm water runoff measurements of copper from a naturally patinated roof and from a parking space. Aspects on environmental fate and chemical speciation.

PubMed

Odnevall Wallinder, I; Hedberg, Y; Dromberg, P

2009-12-01

Release of copper from a naturally aged copper roof on a shopping centre building in a suburban site of Stockholm has been measured during different rain events after its interaction with the internal drainage system and storm drains made of cast iron and concrete. Concentrations of copper removed by means of urban storm water from a nearby parking space have been determined for comparison. Predictions and measurements of the chemical speciation of released copper are discussed compared to the total concentration, and to threshold values for freshwater and drinking water. The results clearly illustrate that the major part of the released copper from the roof is readily retained already during transport through the internal drainage system of the building, a pathway that also changes the chemical speciation of released copper and its bioavailable fraction. Most copper, not retained by cast iron and concrete surfaces, was strongly complexed to organic matter. The median concentration of free cupric ions and weak copper complexes was less than, or within the range of reported no effect concentrations, NOECs, of copper in surface waters. The parking space contributed with significantly higher and time-dependent concentrations of total copper compared to measured concentrations of copper from the roof after the interaction with the drainage system. Most copper in the surface runoff water was strongly complexed with organic matter, hence reducing the bioavailable fraction significantly to concentrations within the NOEC range. Dilution with other sources of urban storm water will reduce the released concentration of copper even further. The results illustrate that already the internal drainage system and the storm drains made of cast iron and concrete act as efficient sinks for released copper which means that any installation of additional infiltration devices is redundant.

Rapid Prototyping: State of the Art Review

DTIC Science & Technology

2003-10-23

Steel H13 Tool Steel CP Ti, Ti-6Al-4V Titanium Tungsten Copper Aluminum Nickel...The company’s LENS 750 and LENS 850 machines (both $440,000 to $640,000) are capable of producing parts in 16 stainless steel , H13 tool steel ...machining. 20 The Arcam EBM S12 model sells for $500,000 and is capable of processing two materials. One is H13 tool steel , while the other

Energy Harvesting from the Stray Electromagnetic Field around the Electrical Power Cable for Smart Grid Applications

PubMed Central

2016-01-01

For wireless sensor node (WSN) applications, this paper presents the harvesting of energy from the stray electromagnetic field around an electrical power line. Inductive and capacitive types of electrodynamic energy harvesters are developed and reported. For the produced energy harvesters, solid core and split-core designs are adopted. The inductive energy harvester comprises a copper wound coil which is produced on a mild steel core. However, the capacitive prototypes comprise parallel, annular discs separated by Teflon spacers. Moreover, for the inductive energy harvesters' wound coil and core, the parametric analysis is also performed. A Teflon housing is incorporated to protect the energy harvester prototypes from the harsh environmental conditions. Among the inductive energy harvesters, prototype-5 has performed better than the other harvesters and produces a maximum rms voltage of 908 mV at the current level of 155 A in the power line. However, at the same current flow, the capacitive energy harvesters produce a maximum rms voltage of 180 mV. The alternating output of the prototype-5 is rectified, and a super capacitor (1 F, 5.5 V) and rechargeable battery (Nickel-Cadmium, 3.8 V) are charged with it. Moreover, with the utilization of a prototype-5, a self-powered wireless temperature sensing and monitoring system for an electrical transformer is also developed and successfully implemented. PMID:27579343

Energy Harvesting from the Stray Electromagnetic Field around the Electrical Power Cable for Smart Grid Applications.

PubMed

Khan, Farid Ullah

For wireless sensor node (WSN) applications, this paper presents the harvesting of energy from the stray electromagnetic field around an electrical power line. Inductive and capacitive types of electrodynamic energy harvesters are developed and reported. For the produced energy harvesters, solid core and split-core designs are adopted. The inductive energy harvester comprises a copper wound coil which is produced on a mild steel core. However, the capacitive prototypes comprise parallel, annular discs separated by Teflon spacers. Moreover, for the inductive energy harvesters' wound coil and core, the parametric analysis is also performed. A Teflon housing is incorporated to protect the energy harvester prototypes from the harsh environmental conditions. Among the inductive energy harvesters, prototype-5 has performed better than the other harvesters and produces a maximum rms voltage of 908 mV at the current level of 155 A in the power line. However, at the same current flow, the capacitive energy harvesters produce a maximum rms voltage of 180 mV. The alternating output of the prototype-5 is rectified, and a super capacitor (1 F, 5.5 V) and rechargeable battery (Nickel-Cadmium, 3.8 V) are charged with it. Moreover, with the utilization of a prototype-5, a self-powered wireless temperature sensing and monitoring system for an electrical transformer is also developed and successfully implemented.

Measurement of labile copper in wine by medium exchange stripping potentiometry utilising screen printed carbon electrodes.

PubMed

Clark, Andrew C; Kontoudakis, Nikolaos; Barril, Celia; Schmidtke, Leigh M; Scollary, Geoffrey R

2016-07-01

The presence of copper in wine is known to impact the reductive, oxidative and colloidal stability of wine, and techniques enabling measurement of different forms of copper in wine are of particular interest in understanding these spoilage processes. Electrochemical stripping techniques developed to date require significant pretreatment of wine, potentially disturbing the copper binding equilibria. A thin mercury film on a screen printed carbon electrode was utilised in a flow system for the direct analysis of labile copper in red and white wine by constant current stripping potentiometry with medium exchange. Under the optimised conditions, including an enrichment time of 500s and constant current of 1.0μA, the response range was linear from 0.015 to 0.200mg/L. The analysis of 52 red and white wines showed that this technique generally provided lower labile copper concentrations than reported for batch measurement by related techniques. Studies in a model system and in finished wines showed that the copper sulfide was not measured as labile copper, and that loss of hydrogen sulfide via volatilisation induced an increase in labile copper within the model wine system. Copyright © 2016 Elsevier B.V. All rights reserved.

Systems design of transformation toughened blast-resistant naval hull steels

NASA Astrophysics Data System (ADS)

Saha, Arup

A systems approach to computational materials design has demonstrated a new class of ultratough, weldable secondary hardened plate steels combining new levels of strength and toughness while meeting processability requirements. A first prototype alloy has achieved property goals motivated by projected naval hull applications requiring extreme fracture toughness (Cv > 85 ft-lbs (115 J) corresponding to KId > 200 ksi.in1/2 (220 MPa.m1/2)) at strength levels of 150--180 ksi (1034--1241 MPa) yield strength in weldable, formable plate steels. A theoretical design concept was explored integrating the mechanism of precipitated nickel-stabilized dispersed austenite for transformation toughening in an alloy strengthened by combined precipitation of M2C carbides and BCC copper both at an optimal ˜3nm particle size for efficient strengthening. This concept was adapted to plate steel design by employing a mixed bainitic/martensitic matrix microstructure produced by air-cooling after solution-treatment and constraining the composition to low carbon content for weldability. With optimized levels of copper and M2C carbide formers based on a quantitative strength model, a required alloy nickel content of 6.5 wt% was predicted for optimal austenite stability for transformation toughening at the desired strength level of 160 ksi (1100 MPa) yield strength. A relatively high Cu level of 3.65 wt% was employed to allow a carbon limit of 0.05 wt% for good weldability. Hardness and tensile tests conducted on the designed prototype confirmed predicted precipitation strengthening behavior in quench and tempered material. Multi-step tempering conditions were employed to achieve the optimal austenite stability resulting in significant increase of impact toughness to 130 ft-lb (176 J) at a strength level of 160 ksi (1100 MPa). Comparison with the baseline toughness-strength combination determined by isochronal tempering studies indicates a transformation toughening increment of 60% in Charpy energy. Predicted Cu particle number densities and the heterogeneous nucleation of optimal stability high Ni 5 nm austenite on nanometer-scale copper precipitates in the multi-step tempered samples was confirmed using three-dimensional atom probe microscopy. Charpy impact tests and fractography demonstrate ductile fracture with C v > 90 ft-lbs (122 J) down to -40°C, with a substantial toughness peak at 25°C consistent with designed transformation toughening behavior. The properties demonstrated in this first prototype represent a substantial advance over existing naval hull steels.

355 nm UV laser patterning and post-processing of FR4 PCB for fine pitch components integration

NASA Astrophysics Data System (ADS)

Dupont, F.; Stoukatch, S.; Laurent, P.; Dricot, S.; Kraft, M.

2018-01-01

Laser direct patterning of fine pitch features on standard PCB (Printed Circuit Board) was investigated. As a feasibility study, eight parameter sets were selected and the smallest achievable grooves and tracks were determined. Three regular FR4 (Flame Resistant 4) PCB substrates have been experimented with. The first two have respectively 18 μm and 35 μm bare copper conductive layer without finish while the third one has a 18 μm copper layer with ENIG (Electroless Nickel Immersion Gold) finish. Laser patterning of PCB conductive structure is a single step, maskless and purely dry operation expected to allow reaching fine pitch features, even on thick copper layers (≥ 18 μm) for which the traditional chemical wet processes encounter underetch problems. Aside PCB complete structuring, a second objective is to evaluate laser post-processing of standard patterned PCB as an economically viable technique to integrate a few fine pitch components on low cost PCBs. This process is suitable for prototyping and for small and medium series. The widths of the smallest grooves and tracks that we achieved were measured about 11 μm and 19 μm on 18 μm thick cooper layer, 13 μm and 39 μm on 35 μm thick cooper layer, and 11 μm and 38 μm on 18 μm cooper layer with ENIG finish. These values are well below what can be achieved with a wet process. Etching results are presented at high magnification both from the top and from a cross-sectioning perspective. The latter allows observation of the TAZ (Thermal Affected Zone) in the conductive layer and the damages in the FR4.

Deficient copper concentrations in dried-defatted hepatic tissue from ob/ob mice: A potential model for study of defective copper regulation in metabolic liver disease.

PubMed

Church, Stephanie J; Begley, Paul; Kureishy, Nina; McHarg, Selina; Bishop, Paul N; Bechtold, David A; Unwin, Richard D; Cooper, Garth J S

2015-05-08

Ob/ob mice provide an animal model for non-alcoholic fatty liver disease/non-alcoholic steatohepatitis (NAFLD/NASH) in patients with obesity and type-2 diabetes. Low liver copper has been linked to hepatic lipid build-up (steatosis) in animals with systemic copper deficiency caused by low-copper diets. However, hepatic copper status in patients with NAFLD or NASH is uncertain, and a validated animal model useful for the study of hepatic copper regulation in common forms of metabolic liver disease is lacking. Here, we report parallel measurements of essential metal levels in whole-liver tissue and defatted-dried liver tissue from ob/ob and non-obese control mice. Measurements in whole-liver tissue from ob/ob mice at an age when they have developed NAFLD/NASH, provide compelling evidence for factitious lowering of copper and all other essential metals by steatosis, and so cannot be used to study hepatic metal regulation in this model. By marked contrast, metal measurements in defatted-dried liver samples reveal that most essential metals were actually normal and indicate specific lowering of copper in ob/ob mice, consistent with hepatic copper deficiency. Thus ob/ob mice can provide a model useful for the study of copper regulation in NAFLD and NASH, provided levels are measured in defatted-dried liver tissue. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

The influence of EI-21 redox ion-exchange resins on the secondary-coolant circuit water chemistry of vehicular nuclear power installations

NASA Astrophysics Data System (ADS)

Moskvin, L. N.; Rakov, V. T.

2015-06-01

The results obtained from testing the secondary-coolant circuit water chemistry of full-scale land-based prototype bench models of vehicular nuclear power installations equipped with water-cooled water-moderated and liquid-metal reactor plants are presented. The influence of copper-containing redox ionexchange resins intended for chemically deoxygenating steam condensate on the working fluid circulation loop's water chemistry is determined. The influence of redox ion-exchange resins on the water chemistry is evaluated by generalizing an array of data obtained in the course of extended monitoring using the methods relating to physicochemical analysis of the quality of condensate-feedwater path media and the methods relating to metallographic analysis of the state of a faulty steam generator's tube system surfaces. The deoxygenating effectiveness of the normal state turbine condensate vacuum deaeration system is experimentally determined. The refusal from applying redox ion-exchange resins in the condensate polishing ion-exchange filters is formulated based on the obtained data on the adverse effect of copper-containing redox ionexchange resins on the condensate-feedwater path water chemistry and based on the data testifying a sufficient effect from using the normal state turbine condensate vacuum deaeration system. Data on long-term operation of the prototype bench model of a vehicular nuclear power installation without subjecting the turbine condensate to chemical deoxygenation are presented.

Effects of chronic copper exposure during early life in rhesus monkeys.

PubMed

Araya, Magdalena; Kelleher, Shannon L; Arredondo, Miguel A; Sierralta, Walter; Vial, María Teresa; Uauy, Ricardo; Lönnerdal, Bo

2005-05-01

Whether infants regulate copper absorption and the potential effects of excess copper in early life remain poorly defined. The objective of the study was to assess copper retention, liver copper content, and liver function in infant rhesus monkeys fed infant formula containing 6.6 mg Cu/L. From birth to 5 mo of age, infant rhesus monkeys were fed formula that was supplemented with copper (0.6 mg Cu/L; n = 5) or not supplemented (n = 4). In all animals, weight and crown-rump length (by anthropometry), hemoglobin, hematocrit, plasma ceruloplasmin activity, and zinc and copper concentrations were measured monthly (birth to 6 mo) and at 8 and 12 mo. When the animals were 1, 5, and 8 mo old, liver copper and metallothionein concentrations, liver histology (by light and electron microscopy), and the number of Kupffer cells were assessed, and 67Cu retention was measured. Liver function was assessed by measurement of plasma alanine aminotransferase, aspartate aminotransferase, gamma-glutamyl transferase, and alkaline phosphatase activities and protein, albumin, bilirubin, and blood urea nitrogen concentrations. 67Cu retention was 19.2% and 10.9% after 1 and 5 mo of copper treatment, respectively, compared with approximately 75% in controls at age 2 mo. At age 8 mo, 67Cu retention was 22.9% in copper-treated animals and 31.5% in controls. Liver histology remained normal by light microscopy, with mild ultrastructural signs of cell damage at 5 mo. Liver copper concentration was 4711, 1139, and 498 microg/g dry tissue at 1, 5, and 8 mo, respectively, in copper-treated animals and 250 microg/g at 2 mo in controls. Measurements could not be completed in all animals. No clinical evidence of copper toxicity was observed. Copper absorption was down-regulated; increases in liver copper content at ages 1 and 5 mo did not result in histologic damage. Ultrastructural changes at age 5 mo could signal early cellular damage.

Comparison of ultrafiltration and solid phase extraction for the separation of free and protein-bound serum copper for the Wilson's disease diagnosis.

PubMed

Bohrer, Denise; Do Nascimento, Paulo Cícero; Ramirez, Adrian G; Mendonça, Jean Karlo A; De Carvalho, Leandro M; Pomblum, Solange Cristina G

2004-07-01

The determination of the ratio free/protein-bound serum copper along with urinary copper can be used as a preliminary test for the Wilson's Disease diagnosis. In this work, the determination of these copper fractions in serum samples was carried out in two different ways; after separation of the copper bound to proteins from the free fraction by a column for protein adsorption and by ultrafiltration. As proteins can be adsorbed onto plastic polymeric surfaces, polyethylene (PE) with different molecular weights in powder form was investigated for protein adsorption. A small column was adapted in a flow system to carry out a solid-phase extraction (SPE) on-line. Preliminary experiments defined conditions for protein retention and elution and column saturation. Good performance was achieved using Mg(NO3)2 solution as carrier and methanol as eluent. The presence of proteins in both fraction (column effluent and eluate) was checked by the Coomassie Brilliant Blue test. Copper was measured by graphite furnace atomic absorption spectrometry. The measurement in the column effluent furnished the free-fraction of copper while the copper measured in the eluate the bound-fraction. The method was compared with ultrafiltration (20 kDa), measuring the free-copper in the ultrafiltrate. For the determination of protein-bound copper, the copper found in the ultrafitrate was discounted from the total copper measured in the sample. Serum samples of 10 individuals were analyzed by both methods with good agreement of the results. The regression plots, obtained by analysing the samples by both methods, presented r2 and slope of 0.97 and 0.96 for free copper and 1.00 and 1.00 for bound copper, respectively. Protein-bound copper (PB) concentrations ranged from 74 to 2074 microg/l and free-copper (F) from 22 to 54 microg/l. The ratio F/PB, calculated from SPE data, was 29.7% for one individual, with Wilson Disease well-characterized, and ranged from 1.2% to 5.2% for the others. The SPE method performed well in terms of accuracy and precision, and showed good agreement with the UF. Advantages of SPE are small sample volume (50 microl), separation carried out in 10 min, and the use of the same column for several analyses. Copyright 2004 Elsevier B.V.

First scientific application of the membrane cryostat technology

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

Montanari, David; Adamowski, Mark; Baller, Bruce R.

2014-01-29

We report on the design, fabrication, performance and commissioning of the first membrane cryostat to be used for scientific application. The Long Baseline Neutrino Experiment (LBNE) has designed and fabricated a membrane cryostat prototype in collaboration with IHI Corporation (IHI). Original goals of the prototype are: to demonstrate the membrane cryostat technology in terms of thermal performance, feasibility for liquid argon, and leak tightness; to demonstrate that we can remove all the impurities from the vessel and achieve the purity requirements in a membrane cryostat without evacuation and using only a controlled gaseous argon purge; to demonstrate that we canmore » achieve and maintain the purity requirements of the liquid argon during filling, purification, and maintenance mode using mole sieve and copper filters from the Liquid Argon Purity Demonstrator (LAPD) R and D project. The purity requirements of a large liquid argon detector such as LBNE are contaminants below 200 parts per trillion oxygen equivalent. This paper gives the requirements, design, construction, and performance of the LBNE membrane cryostat prototype, with experience and results important to the development of the LBNE detector.« less

Carbohydrate metabolism in erythrocytes of copper deficient rats.

PubMed

Brooks, S P J; Cockell, K A; Dawson, B A; Ratnayake, W M N; Lampi, B J; Belonje, B; Black, D B; Plouffe, L J

2003-11-01

Dietary copper deficiency is known to adversely affect the circulatory system of fructose-fed rats. Part of the problem may lie in the effect of copper deficiency on intermediary metabolism. To test this, weanling male Long-Evans rats were fed for 4 or 8 weeks on sucrose-based diets containing low or adequate copper content. Copper deficient rats had significantly lower plasma and tissue copper as well as lower plasma copper, zinc-superoxide dismutase activity. Copper deficient rats also had a significantly higher heart:body weight ratio when compared to pair-fed controls. Direct measurement of glycolysis and pentose phosphate pathway flux in erythrocytes using (13)C NMR showed no differences in carbon flux from glucose or fructose to pyruvate but a significantly higher flux through the lactate dehydrogenase locus in copper deficient rats (approximately 1.3 times, average of glucose and glucose + fructose measurements). Copper-deficient animals had significantly higher erythrocyte concentrations of glucose, fructose, glyceraldehyde 3-phosphate and NAD(+). Liver metabolite levels were also affected by copper deficiency being elevated in glycogen and fructose 1-phosphate content. The results show small changes in carbohydrate metabolism of copper deficient rats.

7 CFR 1755.406 - Shield or armor ground resistance measurements.

Code of Federal Regulations, 2012 CFR

2012-01-01

... or armor ground resistance measurements shall be made on completed lengths of copper cable and wire... measurement shall be made between the copper cable and wire shield and ground and between the fiber optic... instructions. (d) Applicable results. (1) For all new copper cable and wire facilities and all new fiber optic...

7 CFR 1755.406 - Shield or armor ground resistance measurements.

Code of Federal Regulations, 2013 CFR

2013-01-01

... or armor ground resistance measurements shall be made on completed lengths of copper cable and wire... measurement shall be made between the copper cable and wire shield and ground and between the fiber optic... instructions. (d) Applicable results. (1) For all new copper cable and wire facilities and all new fiber optic...

7 CFR 1755.406 - Shield or armor ground resistance measurements.

Code of Federal Regulations, 2014 CFR

2014-01-01

... or armor ground resistance measurements shall be made on completed lengths of copper cable and wire... measurement shall be made between the copper cable and wire shield and ground and between the fiber optic... instructions. (d) Applicable results. (1) For all new copper cable and wire facilities and all new fiber optic...

Absolute measurement of the Hugoniot and sound velocity of liquid copper at multimegabar pressures

DOE PAGES

McCoy, Chad August; Knudson, Marcus David; Root, Seth

2017-11-13

Measurement of the Hugoniot and sound velocity provides information on the bulk modulus and Grüneisen parameter of a material at extreme conditions. The capability to launch multilayered (copper/aluminum) flyer plates at velocities in excess of 20 km/s with the Sandia Z accelerator has enabled high-precision sound-velocity measurements at previously inaccessible pressures. For these experiments, the sound velocity of the copper flyer must be accurately known in the multi-Mbar regime. Here we describe the development of copper as an absolutely calibrated sound-velocity standard for high-precision measurements at pressures in excess of 400 GPa. Using multilayered flyer plates, we performed absolute measurementsmore » of the Hugoniot and sound velocity of copper for pressures from 500 to 1200 GPa. These measurements enabled the determination of the Grüneisen parameter for dense liquid copper, clearly showing a density dependence above the melt transition. As a result, combined with earlier data at lower pressures, these results constrain the sound velocity as a function of pressure, enabling the use of copper as a Hugoniot and sound-velocity standard for pressures up to 1200 GPa.« less

Absolute measurement of the Hugoniot and sound velocity of liquid copper at multimegabar pressures

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

McCoy, Chad August; Knudson, Marcus David; Root, Seth

Measurement of the Hugoniot and sound velocity provides information on the bulk modulus and Grüneisen parameter of a material at extreme conditions. The capability to launch multilayered (copper/aluminum) flyer plates at velocities in excess of 20 km/s with the Sandia Z accelerator has enabled high-precision sound-velocity measurements at previously inaccessible pressures. For these experiments, the sound velocity of the copper flyer must be accurately known in the multi-Mbar regime. Here we describe the development of copper as an absolutely calibrated sound-velocity standard for high-precision measurements at pressures in excess of 400 GPa. Using multilayered flyer plates, we performed absolute measurementsmore » of the Hugoniot and sound velocity of copper for pressures from 500 to 1200 GPa. These measurements enabled the determination of the Grüneisen parameter for dense liquid copper, clearly showing a density dependence above the melt transition. As a result, combined with earlier data at lower pressures, these results constrain the sound velocity as a function of pressure, enabling the use of copper as a Hugoniot and sound-velocity standard for pressures up to 1200 GPa.« less

Development of a Conductivity Sensor for Monitoring Groundwater Resources to Optimize Water Management in Smart City Environments.

PubMed

Parra, Lorena; Sendra, Sandra; Lloret, Jaime; Bosch, Ignacio

2015-08-26

The main aim of smart cities is to achieve the sustainable use of resources. In order to make the correct use of resources, an accurate monitoring and management is needed. In some places, like underground aquifers, access for monitoring can be difficult, therefore the use of sensors can be a good solution. Groundwater is very important as a water resource. Just in the USA, aquifers represent the water source for 50% of the population. However, aquifers are endangered due to the contamination. One of the most important parameters to monitor in groundwater is the salinity, as high salinity levels indicate groundwater salinization. In this paper, we present a specific sensor for monitoring groundwater salinization. The sensor is able to measure the electric conductivity of water, which is directly related to the water salinization. The sensor, which is composed of two copper coils, measures the magnetic field alterations due to the presence of electric charges in the water. Different salinities of the water generate different alterations. Our sensor has undergone several tests in order to obtain a conductivity sensor with enough accuracy. First, several prototypes are tested and are compared with the purpose of choosing the best combination of coils. After the best prototype was selected, it was calibrated using up to 30 different samples. Our conductivity sensor presents an operational range from 0.585 mS/cm to 73.8 mS/cm, which is wide enough to cover the typical range of water salinities. With this work, we have demonstrated that it is feasible to measure water conductivity using solenoid coils and that this is a low cost application for groundwater monitoring.

Development of a Conductivity Sensor for Monitoring Groundwater Resources to Optimize Water Management in Smart City Environments

PubMed Central

Parra, Lorena; Sendra, Sandra; Lloret, Jaime; Bosch, Ignacio

2015-01-01

The main aim of smart cities is to achieve the sustainable use of resources. In order to make the correct use of resources, an accurate monitoring and management is needed. In some places, like underground aquifers, access for monitoring can be difficult, therefore the use of sensors can be a good solution. Groundwater is very important as a water resource. Just in the USA, aquifers represent the water source for 50% of the population. However, aquifers are endangered due to the contamination. One of the most important parameters to monitor in groundwater is the salinity, as high salinity levels indicate groundwater salinization. In this paper, we present a specific sensor for monitoring groundwater salinization. The sensor is able to measure the electric conductivity of water, which is directly related to the water salinization. The sensor, which is composed of two copper coils, measures the magnetic field alterations due to the presence of electric charges in the water. Different salinities of the water generate different alterations. Our sensor has undergone several tests in order to obtain a conductivity sensor with enough accuracy. First, several prototypes are tested and are compared with the purpose of choosing the best combination of coils. After the best prototype was selected, it was calibrated using up to 30 different samples. Our conductivity sensor presents an operational range from 0.585 mS/cm to 73.8 mS/cm, which is wide enough to cover the typical range of water salinities. With this work, we have demonstrated that it is feasible to measure water conductivity using solenoid coils and that this is a low cost application for groundwater monitoring. PMID:26343653

Commissioning and experimental validation of SST-1 plasma facing components

NASA Astrophysics Data System (ADS)

Paravastu, Yuvakiran; Raval, Dilip; Khan, Ziauddin; Patel, Hitesh; Biswas, Prabal; Parekh, Tejas; George, Siju; Santra, Prosenjit; Ramesh, Gattu; ArunPrakash, A.; Thankey, Prashant; Semwal, Pratibha; Dhanani, Kalpeshkumar R.; Jaiswal, Snehal; Chauhan, Pradeep; Pradhan, Subrata

2017-04-01

Plasma facing components of SST-1 are designed to withstand an input heat load of 1.0 MW/m2. They protect vacuum vessel, auxiliary heating source i.e. RF antennas, NBI and other in-vessel diagnostic from the plasma particles and high radiative heat loads. PFC’s are positioned symmetric to mid-plane to accommodate with circular, single and double null configuration. Graphite is used as plasma facing material, back made of copper alloy and SS cooling/baking tubes are brazed on copper alloy back plates for efficient heat removal of incident heat flux. Benchmarking of PFC assembly was first carried out in prototype vacuum vessel of SST-1 to develop understanding and methodology of co-ordinate measurements. Based on such hands-on-experience, the final assembly of PFC’s in vacuum vessel of SST-1 was carried out. Initially, PFC’s are to be baked at 250 °C for wall conditioning followed with cooling for heat removal of incident heat flux during long pulse plasma operation. For this purpose, the supply and return headers are designed and installed inside the vacuum vessel in such a way that it will cater water as well as hot nitrogen gas depending up on the cycle. This paper will discuss the successful installation of PFC’s and its plasma operation respecting all design criteria.

24-hour urine copper test

MedlinePlus

... medlineplus.gov/ency/article/003604.htm 24-hour urine copper test To use the sharing features on this page, please enable JavaScript. The 24-hour urine copper test measures the amount of copper in ...

Activated-Carbon Sorbent With Integral Heat-Transfer Device

NASA Technical Reports Server (NTRS)

Jones, Jack A.; Yavrouian, Andre

1996-01-01

Prototype adsorption device used, for example, in adsorption heat pump, to store natural gas to power automobile, or to separate components of fluid mixtures. Device includes activated carbon held together by binder and molded into finned heat-transfer device providing rapid heating or cooling to enable rapid adsorption or desorption of fluids. Concepts of design and fabrication of device equally valid for such other highly thermally conductive devices as copper-finned tubes, and for such other high-surface-area sorbents as zeolites or silicates.

Oxygen-Free Welding Contact Tips

NASA Technical Reports Server (NTRS)

Pike, James F.

1993-01-01

Contact tips for gas/metal arc welding (GMAW) fabricated from oxygen-free copper. Prototype tips tested in robotic welding, for which application intended. Reduces electrical erosion, increases electrical conductivity, and reduces mechanical wear. Productivity of robotic welding increases while time during welding interrupted for removal and replacement of contact tips minimal. Improves alignment of joints and filler metal, reducing rate of rejection and repair of unacceptable weldments. Utility extends beyond aerospace industry to mass production of various types of hardware, including heavy off-highway construction equipment.

High Power Intermodulation Measurements up to 30 W of High Temperature Superconducting Filters

NASA Technical Reports Server (NTRS)

Wilker, Charles; Carter, Charles F., III; Shen, Zhi-Yuan

1999-01-01

We have demonstrated a high power intermodulation measurement set-up capable of delivering 30 W in each of two fundamental tones. For closely spaced frequencies (less than 35 MHz), the dynamic range of the measurement is limited by the nonlinear performance of the mixer in the front end of the HP71210C spectrum analyzer. A tunable TE(sub 011) mode copper cavity was fabricated in which one of the endwalls could be adjusted shifting its resonant frequency between 5.7 and 6.6 GHz. Since the Q-value of this cavity is high, greater than 10(exp 4), and its bandwidth is small, less than 1 MHz, it can be used to attenuate the two fundamental tones relative to one of the harmonic tones, which greatly enhances the dynamic range of the measurement. This set-up can be used to measure the two-tone intermodulation distortion of any passive microwave device, e.g. a HTS filter, a connector, a cable, etc., over a frequency range of 5.9 to 6.4 GHz and a power range of 0.1 to 30 W. The third order intercept (TOI) of a prototype HTS filter measured at powers up to 30 W was +81.3 dBm.

Development of a solar receiver for an organic Rankine cycle engine

NASA Astrophysics Data System (ADS)

Haskins, H. J.; Taylor, R. M.; Osborn, D. B.

A prototype power conversion assembly (PCA) developed by an American aerospace company is considered. The PCA will be mounted at the focal point of a 12 meter parabolic dish and will produce approximately 20 kW of 3 kHz ac power to a ground-mounted rectifier. The PCA includes a cavity receiver coupled to an organic Rankine cycle engine. The engine working fluid is toluene. The performance goals of the receiver design are to maximize both the thermal efficiency and the heat capacity of the core. The latter goal is desired for stabilizing the PCA operation during intermittent cloud cover. The receiver design is based upon the utilization of a direct-heated copper shell. It was necessary to develop a feasible manufacturing process for assuring a good braze joint between the stainless steel, containing the toluene, and the copper shell.

Synthesis of alkyl- and aryl-amino-substituted anthraquinone derivatives by microwave-assisted copper(0)-catalyzed Ullmann coupling reactions.

PubMed

Baqi, Younis; Müller, Christa E

2010-05-01

This protocol describes the efficient, generally applicable Ullmann coupling reaction of bromaminic acid with alkyl- or aryl-amines in phosphate buffer under microwave irradiation using elemental copper as a catalyst. The reaction leads to a number of biologically active compounds. As a prototypical example, the synthesis of a new, potent antagonist of human platelet P2Y(12) receptors, which has potential as an antithrombotic drug, is described in detail. The optimized protocol includes a description of an appropriate reaction setup, thin layer chromatography for monitoring the reaction and a procedure for the isolation, purification and characterization of the anticipated product. The reaction is performed without the use of a glove box and there is no requirement for an inert atmosphere. The reaction typically proceeds within 2-30 min, the protocol, including workup, generally takes 1-3 h to complete.

Development of a solar receiver for an organic Rankine cycle engine

NASA Technical Reports Server (NTRS)

Haskins, H. J.; Taylor, R. M.; Osborn, D. B.

1981-01-01

A prototype power conversion assembly (PCA) developed by an American aerospace company is considered. The PCA will be mounted at the focal point of a 12 meter parabolic dish and will produce approximately 20 kW of 3 kHz ac power to a ground-mounted rectifier. The PCA includes a cavity receiver coupled to an organic Rankine cycle engine. The engine working fluid is toluene. The performance goals of the receiver design are to maximize both the thermal efficiency and the heat capacity of the core. The latter goal is desired for stabilizing the PCA operation during intermittent cloud cover. The receiver design is based upon the utilization of a direct-heated copper shell. It was necessary to develop a feasible manufacturing process for assuring a good braze joint between the stainless steel, containing the toluene, and the copper shell.

Twin-Screw Extruder Development for the ITER Pellet Injection System

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

Meitner, Steven J; Baylor, Larry R; Combs, Stephen Kirk

The ITER pellet injection system is comprised of devices to form and accelerate pellets, and will be connected to inner wall guide tubes for fueling, and outer wall guide tubes for ELM pacing. An extruder will provide a stream of solid hydrogen isotopes to a secondary section, where pellets are cut and accelerated with a gas gun into the plasma. The ITER pellet injection system is required to provide a plasma fueling rate of 120 Pa-m3/s (900 mbar-L/s) and durations of up to 3000 s. The fueling pellets will be injected at a rate up to 10 Hz and pelletsmore » used to trigger ELMs will be injected at higher rates up to 20 Hz. A twin-screw extruder for the ITER pellet injection system is under development at the Oak Ridge National Laboratory. A one-fifth ITER scale prototype has been built and has demonstrated the production of a continuous solid deuterium extrusion. The 27 mm diameter, intermeshed, counter-rotating extruder screws are rotated at a rate up to ≈5 rpm. Deuterium gas is pre-cooled and liquefied and solidified in separate extruder barrels. The precooler consists of a deuterium gas filled copper coil suspended in a separate stainless steel vessel containing liquid nitrogen. The liquefier is comprised of a copper barrel connected to a Cryomech AL330 cryocooler, which has a machined helical groove surrounded by a copper jacket, through which the pre-cooled deuterium condenses. The lower extruder barrel is connected to a Cryomech GB-37 cryocooler to solidify the deuterium (at ≈15 K) before it is forced through the extruder die. The die forms the extrusion to a 3 mm x 4 mm rectangular cross section. Design improvements have been made to improve the pre-cooler and liquefier heat exchangers, to limit the loss of extrusion through gaps in the screws. This paper will describe the design improvements for the next iteration of the extruder prototype.« less

Evolution of a plant-specific copper chaperone family for chloroplast copper homeostasis

DOE PAGES

Blaby-Haas, Crysten E.; Padilla-Benavides, Teresita; Stübe, Roland; ...

2014-12-02

Metallochaperones traffic copper (Cu +) from its point of entry at the plasma membrane to its destination. In plants, one destination is the chloroplast, which houses plastocyanin, a Cu-dependent electron transfer protein involved in photosynthesis. In this paper, we present a previously unidentified Cu + chaperone that evolved early in the plant lineage by an alternative-splicing event of the pre-mRNA encoding the chloroplast P-type ATPase in Arabidopsis 1 (PAA1). In several land plants, recent duplication events created a separate chaperone-encoding gene coincident with loss of alternative splicing. The plant-specific Cu + chaperone delivers Cu + with specificity for PAA1, whichmore » is flipped in the envelope relative to prototypical bacterial ATPases, compatible with a role in Cu + import into the stroma and consistent with the canonical catalytic mechanism of these enzymes. The ubiquity of the chaperone suggests conservation of this Cu +-delivery mechanism and provides a unique snapshot into the evolution of a Cu + distribution pathway. Finally, we also provide evidence for an interaction between PAA2, the Cu +-ATPase in thylakoids, and the Cu +-chaperone for Cu/Zn superoxide dismutase (CCS), uncovering a Cu + network that has evolved to fine-tune Cu + distribution.« less

Non-resonant electromagnetic energy harvester for car-key applications

NASA Astrophysics Data System (ADS)

Li, X.; Hehn, T.; Thewes, M.; Kuehne, I.; Frey, A.; Scholl, G.; Manoli, Y.

2013-12-01

This paper presents a novel non-resonant electromagnetic energy harvester for application in a remote car-key, to extend the lifetime of the battery or even to realize a fully energy autonomous, maintenance-free car-key product. Characteristic for a car-key are low frequency and large amplitude motions during normal daily operation. The basic idea of this non-resonant generator is to use a round flat permanent magnet moving freely in a round flat cavity, which is packaged on both sides by printed circuit boards embedded with multi-layer copper coils. The primary goal of this structure is to easily integrate the energy harvester with the existing electrical circuit module into available commercial car-key designs. The whole size of the energy harvester is comparable to a CR2032 coin battery. To find out the best power-efficient and optimal design, several magnets with different dimensions and magnetizations, and various layouts of copper coils were analysed and built up for prototype testing. Experimental results show that with an axially magnetized NdFeB magnet and copper coils of design variant B a maximum open circuit voltage of 1.1V can be observed.

Multi-Pulse Excitation for Underwater Analysis of Copper-Based Alloys Using a Novel Remote Laser-Induced Breakdown Spectroscopy (LIBS) System.

PubMed

Guirado, Salvador; Fortes, Francisco J; Laserna, J Javier

2016-04-01

In this work, the use of multi-pulse excitation has been evaluated as an effective solution to mitigate the preferential ablation of the most volatile elements, namely Sn, Pb, and Zn, observed during laser-induced breakdown spectroscopy (LIBS) analysis of copper-based alloys. The novel remote LIBS prototype used in this experiments featured both single-pulse (SP-LIBS) and multi-pulse excitation (MP-LIBS). The remote instrument is capable of performing chemical analysis of submersed materials up to a depth of 50 m. Laser-induced breakdown spectroscopy analysis was performed at air pressure settings simulating the conditions during a real subsea analysis. A set of five certified bronze standards with variable concentration of Cu, As, Sn, Pb, and Zn were used. In SP-LIBS, signal emission is strongly sensitive to ambient pressure. In this case, fractionation effect was observed. Multi-pulse excitation circumvents the effect of pressure over the quantitative analysis, thus avoiding the fractionation phenomena observed in single pulse LIBS. The use of copper as internal standard minimizes matrix effects and discrepancies due to variation in ablated mass. © The Author(s) 2016.

Mechanical testing and development of the helical field coil joint for the Advanced Toroidal Facility

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

Nelson, B.E.; Bryan, W.E.; Goranson, P.L.

1985-01-01

The helical field (HF) coil set for the Advanced Toroidal Facility (ATF) is an M = 12, l = 2, constant-ratio torsatron winding consisting of 2 coils, each with 14 turns of heavy copper conductor. The coils are divided into 24 identical segments to facilitate fabrication and minimize the assembly schedule. The segments are connected across through-bolted lap joints that must carry up to 124,000 A per turn for 5 s or 62,500 A steady-state. In addition, the joints must carry the high magnetic and thermal loads induced in the conductor and still fit within the basic 140- by 30-mmmore » copper envelope. Extensive testing and development were undertaken to verify and refine the basic joint design. Tests included assembly force and clamping force for various types of misalignment; joint resistance as a function of clamping force; clamp bolt relaxation due to thermal cycling; fatigue testing of full-size, multiturn joint prototypes; and low-cycle fatigue and tensile tests of annealed CDA102 copper. The required performance parameters and actual test results, as well as the final joint configuration, are presented. 2 refs., 9 figs., 4 tabs.« less

Propagation distance-resolved characteristics of filament-induced copper plasma

DOE PAGES

Ghebregziabher, Isaac; Hartig, Kyle C.; Jovanovic, Igor

2016-03-02

Copper plasma generated at different filament-copper interaction points was characterized by spectroscopic, acoustic, and imaging measurements. The longitudinal variation of the filament intensity was qualitatively determined by acoustic measurements in air. The maximum plasma temperature was measured at the location of peak filament intensity, corresponding to the maximum mean electron energy during plasma formation. The highest copper plasma density was measured past the location of the maximum electron density in the filament, where spectral broadening of the filament leads to enhanced ionization. Acoustic measurements in air and on solid target were correlated to reconstructed plasma properties. Lastly, optimal line emissionmore » is measured near the geometric focus of the lens used to produce the filament.« less

Multiple harmonic frequencies resonant cavity design and half-scale prototype measurements for a fast kicker

DOE PAGES

Huang, Yulu; Wang, Haipeng; Wang, Shaoheng; ...

2016-12-09

Quarter wavelength resonator (QWR) based deflecting cavities with the capability of supporting multiple odd-harmonic modes have been developed for an ultrafast periodic kicker system in the proposed Jefferson Lab Electron Ion Collider (JLEIC, formerly MEIC). Previous work on the kicking pulse synthesis and the transverse beam dynamics tracking simulations show that a flat-top kicking pulse can be generated with minimal emittance growth during injection and circulation of the cooling electron bunches. This flat-top kicking pulse can be obtained when a DC component and 10 harmonic modes with appropriate amplitude and phase are combined together. To support 10 such harmonic modes,more » four QWR cavities are used with 5, 3, 1, and 1 modes, respectively. In the multiple-mode cavities, several slightly tapered segments of the inner conductor are introduced to tune the higher order deflecting modes to be harmonic, and stub tuners are used to fine tune each frequency to compensate for potential errors. In this paper, we summarize the electromagnetic design of the five-mode cavity, including the geometry optimization to get high transverse shunt impedance, the frequency tuning and sensitivity analysis, and the single loop coupler design for coupling to all of the harmonic modes. In particular we report on the design and fabrication of a half-scale copper prototype of this proof-of-principle five-odd-mode cavity, as well as the rf bench measurements. Lastly, we demonstrate mode superposition in this cavity experimentally, which illustrates the kicking pulse generation concept.« less

Electrochemical characterization of bulk and thin film copper in ammonia- and nitric acid-based slurries for chemical mechanical planarization of interconnects

NASA Astrophysics Data System (ADS)

Sainio, Carlyn Anne

Copper will be replacing aluminum as the interconnect material in silicon integrated circuits. Chemical mechanical planarization (CMP) in combination with an inlaid metal interconnection scheme has been utilized to pattern copper interconnects. The thesis describes an attempt to understand the electrochemistry of copper in slurries used for CMP. Steady-state electrochemical potential measurements, linear polarization resistance determinations, and potentiodynamic and potentiostatic polarization scans have been used in order to characterize the mechanism by which copper is removed during CMP. Electrochemical measurements were implemented on a rotating disk assembly to simulate conditions during CMP. Experiments were performed on both bulk copper samples and blanket copper thin films sputter deposited onto silicon wafers. Electrochemical potential measurements have been used in conjunction with potential-pH diagrams to determine the possible copper species which are stable during CMP. Electrochemical results were correlated to CMP experiments to determine slurry compositions with optimum potential-pH ranges for copper planarization. The results indicate that such studies present an opportunity to isolate the electrochemical and chemical effects from the mechanical effects in the CMP of metals and to determine the dependencies of each of these effects on the other. CMP of copper was controlled by the removal of native or non-native surface films. High CMP rates were achieved by matching the rates of film formation and copper and film dissolution. During CMP, surface films are abraded, allowing increased dissolution of copper until the surface film reforms. When the surface was indented by abrasive particles, the corrosion rate of the exposed copper increased by two orders of magnitude. Etchants (i.e. ammonia or nitric acid) were necessary for high CMP rates (120-240 nm/min) and to minimize scratching. CMP rates of copper in 1 volume percent NHsb4OH and 0.7 volume percent HNOsb3 with 0.0016 weight percent KMnOsb4 were comparable. Electrochemical characterization can narrow the possible slurry compositions that may be used for polishing. Also, the possibility of implementing electrochemical techniques to detect the endpoint of polishing was investigated. Although electrochemical measurements in ammonia-based slurries did not indicate when tantalum was exposed, similar measurements may be used to determine when polishing pads should be replaced.

Cell density dependence of Microcystis aeruginosa responses to copper algaecide concentrations: Implications for microcystin-LR release.

PubMed

Kinley, Ciera M; Iwinski, Kyla J; Hendrikse, Maas; Geer, Tyler D; Rodgers, John H

2017-11-01

Along with mechanistic models, predictions of exposure-response relationships for copper are often derived from laboratory toxicity experiments with standardized experimental exposures and conditions. For predictions of copper toxicity to algae, cell density is a critical factor often overlooked. For pulse exposures of copper-based algaecides in aquatic systems, cell density can significantly influence copper sorbed by the algal population, and consequent responses. A cyanobacterium, Microcystis aeruginosa, was exposed to a copper-based algaecide over a range of cell densities to model the density-dependence of exposures, and effects on microcystin-LR (MC-LR) release. Copper exposure concentrations were arrayed to result in a gradient of MC-LR release, and masses of copper sorbed to algal populations were measured following exposures. While copper exposure concentrations eliciting comparable MC-LR release ranged an order of magnitude (24-h EC50s 0.03-0.3mg Cu/L) among cell densities of 10 6 through 10 7 cells/mL, copper doses (mg Cu/mg algae) were similar (24-h EC50s 0.005-0.006mg Cu/mg algae). Comparisons of MC-LR release as a function of copper exposure concentrations and doses provided a metric of the density dependence of algal responses in the context of copper-based algaecide applications. Combined with estimates of other site-specific factors (e.g. water characteristics) and fate processes (e.g. dilution and dispersion, sorption to organic matter and sediments), measuring exposure-response relationships for specific cell densities can refine predictions for in situ exposures and algal responses. These measurements can in turn decrease the likelihood of amending unnecessary copper concentrations to aquatic systems, and minimize risks for non-target aquatic organisms. Copyright © 2017 Elsevier Inc. All rights reserved.

Copper(II) binding by dissolved organic matter: Importance of the copper-to-dissolved organic matter ratio and implications for the Biotic Ligand Model

USGS Publications Warehouse

Craven, Alison M.; Aiken, George R.; Ryan, Joseph N.

2012-01-01

The ratio of copper to dissolved organic matter (DOM) is known to affect the strength of copper binding by DOM, but previous methods to determine the Cu2+–DOM binding strength have generally not measured binding constants over the same Cu:DOM ratios. In this study, we used a competitive ligand exchange–solid-phase extraction (CLE-SPE) method to determine conditional stability constants for Cu2+–DOM binding at pH 6.6 and 0.01 M ionic strength over a range of Cu:DOM ratios that bridge the detection windows of copper-ion-selective electrode and voltammetry measurements. As the Cu:DOM ratio increased from 0.0005 to 0.1 mg of Cu/mg of DOM, the measured conditional binding constant (cKCuDOM) decreased from 1011.5 to 105.6 M–1. A comparison of the binding constants measured by CLE-SPE with those measured by copper-ion-selective electrode and voltammetry demonstrates that the Cu:DOM ratio is an important factor controlling Cu2+–DOM binding strength even for DOM isolates of different types and different sources and for whole water samples. The results were modeled with Visual MINTEQ and compared to results from the biotic ligand model (BLM). The BLM was found to over-estimate Cu2+ at low total copper concentrations and under-estimate Cu2+ at high total copper concentrations.

Study of sintering behavior of vapor forms of 1-octanethiol coated copper nanoparticles for application to ink-jet printing technology.

PubMed

Kwon, Jinhyeong; Park, Shinyoung; Haque, Md Mominul; Kim, Young-Seok; Lee, Caroline Sunyong

2012-04-01

Sub-50 nm copper nanoparticles coated with sub-5 nm 1-octanethiol layer for oxidation inhibition were examined to confirm the 1-octanethiol removal temperature as the sub-50 nm copper nanoparticles are sintered. As a result, 1-octanethiol Self-Assembled Multi-layers (SAMs) on sub-50 nm copper nanoparticles were successfully removed before sintering of copper nanoparticles so that a high density of copper line could be obtained. Finally, the line resistivity was measured and compared to verify the effect of sintering in different atmospheres. As a result, electrical resistivity of the copper pattern sintered in hydrogen atmosphere was measured at 6.96 x 10(-6) ohm-cm whereas that of the copper pattern sintered in mixed gas atmosphere was measured at 2.62 x 10(-5) ohm-cm. Thus, sintering of copper patterns was successfully done to show low electrical resistivity values. Moreover, removal of 1-octanethiol coating after sintering process was confirmed using X-ray photoelectron spectroscopy (XPS) analysis. By showing no sulfur content, XPS results indicate that 1-octanethiol is completely removed. Therefore, the vapor form of 1-octanethiol coating layers can be safely used as an oxidation inhibition layer for low temperature sintering processes and ink-jet applications.

Implementing a prototyping network for injection moulded imaging lenses in Finland

NASA Astrophysics Data System (ADS)

Keränen, K.; Mäkinen, J.-T.; Pääkkönen, E. J.; Koponen, M.; Karttunen, M.; Hiltunen, J.; Karioja, P.

2005-10-01

A network for prototyping imaging lenses using injection moulding was established in Finland. The network consists of several academic and industrial partners capable of designing, processing and characterising imaging lenses produced by injection moulding technology. In order to validate the operation of the network a demonstrator lens was produced. The process steps included in the manufacturing were lens specification, designing and modelling, material selection, mould tooling, moulding process simulation, injection moulding and characterisation. A magnifying imaging singlet lens to be used as an add-on in a camera phone was selected as a demonstrator. The design of the add-on lens proved to be somewhat challenging, but a double aspheric singlet lens design fulfilling nearly the requirement specification was produced. In the material selection task the overall characteristics profile of polymethyl methacrylate (PMMA) material was seen to be the most fitting to the pilot case. It is a low cost material with good moulding properties and therefore it was selected as a material for the pilot lens. Lens mould design was performed using I-DEAS and tested by using MoldFlow 3D injection moulding simulation software. The simulations predicted the achievable lens quality in the processing, when using a two-cavity mould design. First cavity was tooled directly into the mould plate and the second cavity was made by tooling separate insert pieces for the mould. Mould material was steel and the inserts were made from Moldmax copper alloy. Parts were tooled with high speed milling machines. Insert pieces were hand polished after tooling. Prototype lenses were injection moulded using two PMMA grades, namely 6N and 7N. Different process parameters were also experimented in the injection moulding test runs. Prototypes were characterised by measuring mechanical dimensions, surface profile, roughness and MTF of the lenses. Characterisations showed that the lens surface RMS roughness was 30-50 nm and the profile deviation was 5 μm from the design at a distance of 0.3 mm from the lens vertex. These manufacturing defects caused that the measured MTF values were lower than designed. The lens overall quality, however, was adequate to demonstrate the concept successfully. Through the implementation of the demonstrator lens we could test effectively different stages of the manufacturing process and get information about process component weight and risk factors and validate the overall performance of the network.

Testing the Underlying Chemical Principles of the Biotic Ligand Model (BLM) to Marine Copper Systems: Measuring Copper Speciation Using Fluorescence Quenching.

PubMed

Tait, Tara N; McGeer, James C; Smith, D Scott

2018-01-01

Speciation of copper in marine systems strongly influences the ability of copper to cause toxicity. Natural organic matter (NOM) contains many binding sites which provides a protective effect on copper toxicity. The purpose of this study was to characterize copper binding with NOM using fluorescence quenching techniques. Fluorescence quenching of NOM with copper was performed on nine sea water samples. The resulting stability constants and binding capacities were consistent with literature values of marine NOM, showing strong binding with [Formula: see text] values from 7.64 to 10.2 and binding capacities ranging from 15 to 3110 nmol mg [Formula: see text] Free copper concentrations estimated at total dissolved copper concentrations corresponding to previously published rotifer effect concentrations, in the same nine samples, were statistically the same as the range of free copper calculated for the effect concentration in NOM-free artificial seawater. These data confirms the applicability of fluorescence spectroscopy techniques for NOM and copper speciation characterization in sea water and demonstrates that such measured speciation is consistent with the chemical principles underlying the biotic ligand model approach for bioavailability-based metals risk assessment.

Copper induces vasorelaxation and antagonizes noradrenaline-induced vasoconstriction in rat mesenteric artery.

PubMed

Wang, Yu-Chun; Hu, Chao-Wei; Liu, Ming-Yu; Jiang, Hong-Chao; Huo, Rong; Dong, De-Li

2013-01-01

Copper is an essential trace element for normal cellular function and contributes to critical physiological or pathological processes. The aim of the study was to investigate the effects of copper on vascular tone of rat mesenteric artery and compare the effects of copper on noradrenaline (NA) and high K(+) induced vasoconstriction. The rat mesenteric arteries were isolated and the vessel tone was measured by using multi wire myograph system in vitro. Blood pressure of carotid artery in rabbits was measured by using physiological data acquisition and analysis system in vivo. Copper dose-dependently blunted NA-induced vasoconstriction of rat mesenteric artery. Copper-induced vasorelaxation was inhibited when the vessels were pretreated with NG-nitro-L-arginine methyl ester (L-NAME). Copper did not blunt high K(+)-induced vasoconstriction. Copper preincubation inhibited NA-evoked vasoconstriction and the inhibition was not affected by the presence of L-NAME. Copper preincubation showed no effect on high K(+)-evoked vasoconstriction. Copper chelator diethyldithiocarbamate trihydrate (DTC) antagonized the vasoactivity induced by copper in rat mesenteric artery. In vivo experiments showed that copper injection (iv) significantly decreased blood pressure of rabbits and NA or DTC injection (iv) did not rescue the copper-induced hypotension and animal death. Copper blunted NA but not high K(+)-induced vasoconstriction of rat mesenteric artery. The acute effect of copper on NA-induced vasoconstriction was depended on nitric oxide (NO), but the effect of copper pretreatment on NA-induced vasoconstriction was independed on NO, suggesting that copper affected NA-induced vasoconstriction by two distinct mechanisms. © 2013 S. Karger AG, Basel.

HOM identification by bead pulling in the Brookhaven ERL cavity

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

Hahn H.; Calaga, R.; Jain, P.

2012-06-25

Several past measurements of the Brookhaven ERL at superconducting temperature produced a long list of higher order modes (HOMs). The Niobium 5-cell cavity is terminated with HOM ferrite dampers that successfully reduce the Q-factors to tolerable levels. However, a number of undamped resonances with Q {ge} 10{sup 6} were found at 4 K and their mode identification remained as a goal for this paper. The approach taken here consists in taking different S{sub 21} measurements on a copper cavity replica of the ERL which can be compared with the actual data and also with Microwave Studio computer simulations. Several differentmore » S{sub 21} transmission measurements are used, including those taken from the fundamental input coupler to the pick-up probe across the cavity, between probes in a single cell, and between beam-position monitor probes in the beam tubes. Mode identification is supported by bead pulling with a metallic needle or a dielectric sphere that are calibrated in the fundamental mode. This paper presents results for HOMs in the first two dipole bands with the prototypical 958 MHz trapped mode, the lowest beam tube resonances, and high-Q modes in the first quadrupole band and beyond.« less

Aberrant expression of copper associated genes after copper accumulation in COMMD1-deficient dogs.

PubMed

Favier, Robert P; Spee, Bart; Fieten, Hille; van den Ingh, Ted S G A M; Schotanus, Baukje A; Brinkhof, Bas; Rothuizen, Jan; Penning, Louis C

2015-01-01

COMMD1-deficient dogs progressively develop copper-induced chronic hepatitis. Since high copper leads to oxidative damage, we measured copper metabolism and oxidative stress related gene products during development of the disease. Five COMMD1-deficient dogs were studied from 6 months of age over a period of five years. Every 6 months blood was analysed and liver biopsies were taken for routine histological evaluation (grading of hepatitis), rubeanic acid copper staining and quantitative copper analysis. Expression of genes involved in copper metabolism (COX17, CCS, ATOX1, MT1A, CP, ATP7A, ATP7B, ) and oxidative stress (SOD1, catalase, GPX1 ) was measured by qPCR. Due to a sudden death of two animals, the remaining three dogs were treated with d-penicillamine from 43 months of age till the end of the study. Presented data for time points 48, 54, and 60 months was descriptive only. A progressive trend from slight to marked hepatitis was observed at histology, which was clearly preceded by an increase in semi-quantitative copper levels starting at 12 months until 42 months of age. During the progression of hepatitis most gene products measured were transiently increased. Most prominent was the rapid increase in the copper binding gene product MT1A mRNA levels. This was followed by a transient increase in ATP7A and ATP7B mRNA levels. In the sequence of events, copper accumulation induced progressive hepatitis followed by a transient increase in gene products associated with intracellular copper trafficking and temporal activation of anti-oxidative stress mechanisms. Copyright © 2014 Elsevier GmbH. All rights reserved.

Juvenile roach (Rutilus rutilus) increase their anaerobic metabolism in response to copper exposure in laboratory conditions.

PubMed

Maes, Virginie; Betoulle, Stéphane; Jaffal, Ali; Dedourge-Geffard, Odile; Delahaut, Laurence; Geffard, Alain; Palluel, Olivier; Sanchez, Wilfried; Paris-Palacios, Séverine; Vettier, Aurélie; David, Elise

2016-07-01

This study aims to determine the potential impairment of cell energy synthesis processes (glycolysis and respiratory chain pathways) by copper in juvenile roach at different regulation levels by using a multi-marker approach. Juvenile roach were exposed to 0, 10, 50, and 100 µg/L of copper for 7 days in laboratory conditions. The glycolysis pathway was assessed by measuring the relative expression levels of 4 genes encoding glycolysis enzymes. The respiratory chain was studied by assessing the electron transport system and cytochrome c oxidase gene expression. Muscle mitochondria ultrastructure was studied, and antioxidant responses were measured. Furthermore, the main energy reserves-carbohydrates, lipids, and proteins-were measured, and cellular energy was evaluated by measuring ATP, ADP, AMP and IMP concentrations. This study revealed a disturbance of the cell energy metabolism due to copper exposure, with a significant decrease in adenylate energy charge in roach exposed to 10 μg/L of copper after 1 day. Moreover, ATP concentrations significantly decreased in roach exposed to 10 μg/L of copper after 1 day. This significant decrease persisted in roach exposed to 50 µg/L of copper after 7 days. AMP concentrations increased in all contaminated fish after 1 day of exposure. In parallel, the relative expression of 3 genes encoding for glycolysis enzymes increased in all contaminated fish after 1 day of copper exposure. Focusing on the respiratory chain, cytochrome c oxidase gene expression also increased in all contaminated fish at the two time-points. The activity of the electron transport system was not disturbed by copper, except in roach exposed to 100 µg/L of copper after 1 day. Copper induced a metabolic stress. Juvenile roach seemed to respond to the ensuing high energy demand by increasing their anaerobic metabolism, but the energy produced by the anaerobic metabolism is unable to compensate for the stress induced by copper after 7 days. This multi-marker approach allows us to reach a greater understanding of the effects of copper on the physiological responses of juvenile roach.

Detection of Genetically Altered Copper Levels in Drosophila Tissues by Synchrotron X-Ray Fluorescence Microscopy

PubMed Central

Lye, Jessica C.; Hwang, Joab E. C.; Paterson, David; de Jonge, Martin D.; Howard, Daryl L.; Burke, Richard

2011-01-01

Tissue-specific manipulation of known copper transport genes in Drosophila tissues results in phenotypes that are presumably due to an alteration in copper levels in the targeted cells. However direct confirmation of this has to date been technically challenging. Measures of cellular copper content such as expression levels of copper-responsive genes or cuproenzyme activity levels, while useful, are indirect. First-generation copper-sensitive fluorophores show promise but currently lack the sensitivity required to detect subtle changes in copper levels. Moreover such techniques do not provide information regarding other relevant biometals such as zinc or iron. Traditional techniques for measuring elemental composition such as inductively coupled plasma mass spectroscopy are not sensitive enough for use with the small tissue amounts available in Drosophila research. Here we present synchrotron x-ray fluorescence microscopy analysis of two different Drosophila tissues, the larval wing imaginal disc, and sectioned adult fly heads and show that this technique can be used to detect changes in tissue copper levels caused by targeted manipulation of known copper homeostasis genes. PMID:22053217

Development of the ITER ICH Transmission Line and Matching System

NASA Astrophysics Data System (ADS)

Rasmussen, D. A.; Goulding, R. H.; Pesavento, P. V.; Peters, B.; Swain, D. W.; Fredd, E. H.; Hosea, J.; Greenough, N.

2011-10-01

The ITER Ion Cyclotron Heating (ICH) System is designed to couple 20 MW of heating power for ion and electron heating. Prototype components for the ITER Ion Cyclotron Heating (ICH) transmission line and matching system are being designed and tested. The ICH transmission lines are pressurized 300 mm diameter coaxial lines with water-cooled aluminum outer conductor and gas-cooled and water-cooled copper inner conductor. Each ICH transmission line is designed to handle 40-55 MHz power at up to 6 MW/line. A total of 8 lines split to 16 antenna inputs on two ICH antennas. Industrial suppliers have designed coaxial transmission line and matching components and prototypes will be manufactured. The prototype components will be qualified on a test stand operating at the full power and pulse length needed for ITER. The matching system must accommodated dynamic changes in the plasma loading due to ELMS and the L to H-mode transition. Passive ELM tolerance will be performed using hybrid couplers and loads, which can absorb the transient reflected power. The system is also designed to compensate for the mutual inductances of the antenna current straps to limit the peak voltages on the antenna array elements.

Binding of copper to lysozyme: Spectroscopic, isothermal titration calorimetry and molecular docking studies

NASA Astrophysics Data System (ADS)

Jing, Mingyang; Song, Wei; Liu, Rutao

2016-07-01

Although copper is essential to all living organisms, its potential toxicity to human health have aroused wide concerns. Previous studies have reported copper could alter physical properties of lysozyme. The direct binding of copper with lysozyme might induce the conformational and functional changes of lysozyme and then influence the body's resistance to bacterial attack. To better understand the potential toxicity and toxic mechanisms of copper, the interaction of copper with lysozyme was investigated by biophysical methods including multi-spectroscopic measurements, isothermal titration calorimetry (ITC), molecular docking study and enzyme activity assay. Multi-spectroscopic measurements proved that copper quenched the intrinsic fluorescence of lysozyme in a static process accompanied by complex formation and conformational changes. The ITC results indicated that the binding interaction was a spontaneous process with approximately three thermodynamical binding sites at 298 K and the hydrophobic force is the predominant driven force. The enzyme activity was obviously inhibited by the addition of copper with catalytic residues Glu 35 and Asp 52 locating at the binding sites. This study helps to elucidate the molecular mechanism of the interaction between copper and lysozyme and provides reference for toxicological studies of copper.

Extracellular and circulating redox- and metalloregulated eRNA and eRNP: copper ion-structured RNA cytokines (angiotropin ribokines) and bioaptamer targets imparting RNA chaperone and novel biofunctions to S100-EF-hand and disease-associated proteins.

PubMed

Wissler, Josef H

2004-06-01

Bioassays for cellular differentiation and tissue morphogenesis were used to design methods for isolation of bioactive redox- and metalloregulated nucleic acids and copper ion complexes with proteins from extracellular, circulating, wound, and supernatant fluids of cultured cells. In extracellular biospheres, diversities of nucleic acids were found to be secreted by cells upon activation. They may reflect nucleic acid biolibraries with molecular imprints of cellular history. After removal of protein components, eRNA prototypes exuded by activated cells were sequenced. They are small, endogenous, highly modified and edited, redox- and metalloregulated 5'-end phosphorylated extracellular eRNA (approximately 2-200 bases) with cellular, enzymic, and bioaptamer functions. Fenton-type OH* radical redox reactions may form modified nucleotides in RNA as wobbles eRNA per se, or as copper ion-complex with protein (e.g., S100A12-EF-hand protein, angiotropin-related protein, calgranulin-C, hippocampal neurite differentiation factor) are shown to be bioactive in vivo and in vitro as cytokines (ribokines) and as nonmitogenic angiomorphogens for endothelial cell differentiation in the formation of organoid supracellular capillary structures. As bioaptamers, copper ion-structured eRNA imparts novel biofunctions to proteins that they do not have on their own. The origin of extracellular RNA and intermediate precursors (up to 500 bases) was traced to intracellular parent nucleic acids. Intermediate precursors with and without partial homology were found. This suggests that bioaptamers are not directly retranslatable gene products. Metalloregulated eRNA bioaptamer function was investigated by domains (e.g. 5'...CUG...3' hairpin loop) for folding, bioactivity, and binding of protein with copper, calcium, and alkali metal ion affinity. Vice versa, metalloregulated nucleic acid-binding domains (K3H, R3H) in proteins were identified. Interaction of protein and eRNA docking potentials were visualized by 3D-rapid prototyping of accurate molecular image models based on crystallographic or NMR data. For S100A12-homologous proteins, receptor- and metalloregulated RNA chaperone-shaped protein assemblies were investigated. They suggest insight into signaling cascades as to how eRNA transmits its cytokine (ribokine) bioinformation from the extracellular RNA biosphere into cells. Proteomics of the extracellular RNA biosphere demonstrate the presence of nucleic acid-binding domain homologies in defense-, aging-, and disease-associated neuronal and other proteins as targets for RNA orphans. By structural relationships found to transmissible processes, proteinaceous transfer ("infectivity") and feedback of bioinformation beyond the central dogma of molecular biology are considered in terms of metalloregulated RNA bioaptamer function, nucleic acid-binding domains, and protein conformation.

40 CFR 141.80 - General requirements.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) NATIONAL PRIMARY DRINKING WATER REGULATIONS Control of Lead and Copper § 141.80 General requirements. (a... drinking water regulations for lead and copper. Unless otherwise indicated, each of the provisions of this... and copper action levels measured in samples collected at consumers' taps. (c) Lead and copper action...

Trace copper measurements and electrical effects in LPE HgCdTe

NASA Astrophysics Data System (ADS)

Tower, J. P.; Tobin, S. P.; Norton, P. W.; Bollong, A. B.; Socha, A.; Tregilgas, J. H.; Ard, C. K.; Arlinghaus, H. F.

1996-08-01

Recent improvements in sputter initiated resonance ionization spectroscopy (SIRIS) have now made it possible to measure copper in HgCdTe films into the low 1013 cm-3 range. We have used this technique to show that copper is responsible for type conversion in n-type HgCdTe films. Good n-type LPE films were found to have less than 1 x 1014 cm-3 copper, while converted p-type samples were found to have copper concentrations approximately equal to the hole concentrations. Some compensated n-type samples with low mobilities have copper concentrations too low to account for the amount of compensation and the presence of a deep acceptor level is suggested. In order to study diffusion of copper from substrates into LPE layers, a CdTe boule was grown intentionally spiked with copper at approximately 3 x 1016 cm-3. Annealing HgCdTe films at 360°C was found to greatly increase the amount of copper that diffuses out of the substrates and a substrate screening technique was developed based on this phenomenon. SIRIS depth profiles showed much greater copper in HgCdTe films than in the substrates, indicating that copper is preferentially attracted to HgCdTe over Cd(Zn)Te. SIRIS spatial mapping showed that copper is concentrated in substrate tellurium inclusions 5 25 times greater than in the surrounding CdZnTe matrix.

Photoresponses in Gold Nanoparticle Single-Electron Transistors with Molecular Floating Gates

NASA Astrophysics Data System (ADS)

Noguchi, Yutaka; Yamamoto, Makoto; Ishii, Hisao; Ueda, Rieko; Terui, Toshifumi; Imazu, Keisuke; Tamada, Kaoru; Sakano, Takeshi; Matsuda, Kenji

2013-11-01

We have proposed a simple method of activating advanced functions in single-electron transistors (SETs) based on the specific properties of individual molecules. As a prototype, we fabricated a copper phthalocyanine (CuPc)-doped SET. The device consists of a gold-nanoparticle (GNP)-based SET doped with CuPc as a photoresponsive floating gate. In this paper, we report the details of the photoresponses of the CuPc-doped SET, such as conductance switching, sensitivity to the wavelength of the incident light, and multiple induced states.

Nanostructures formed by displacement of porous silicon with copper: from nanoparticles to porous membranes

PubMed Central

2012-01-01

The application of porous silicon as a template for the fabrication of nanosized copper objects is reported. Three different types of nanostructures were formed by displacement deposition of copper on porous silicon from hydrofluoric acid-based solutions of copper sulphate: (1) copper nanoparticles, (2) quasi-continuous copper films, and (3) free porous copper membranes. Managing the parameters of porous silicon (pore sizes, porosity), deposition time, and wettability of the copper sulphate solution has allowed to achieve such variety of the copper structures. Elemental and structural analyses of the obtained structures are presented. Young modulus measurements of the porous copper membrane have been carried out and its modest activity in surface enhanced Raman spectroscopy is declared. PMID:22916840

Determining the Amount of Copper(II) Ions in a Solution Using a Smartphone

ERIC Educational Resources Information Center

Montangero, Marc

2015-01-01

When dissolving copper in nitric acid, copper(II) ions produce a blue-colored solution. It is possible to determine the concentration of copper(II) ions, focusing on the hue of the color, using a smartphone camera. A free app can be used to measure the hue of the solution, and with the help of standard copper(II) solutions, one can graph a…

Diffusive Milli-Gels (DMG) for in situ assessment of metal bioavailability: A comparison with labile metal measurement using Chelex columns and acute toxicity to Ceriodaphnia dubia for copper in freshwaters.

PubMed

Perez, Magali; Simpson, Stuart L; Lespes, Gaëtane; King, Josh J; Adams, Merrin S; Jarolimek, Chad V; Grassl, Bruno; Schaumlöffel, Dirk

2016-12-01

Fluctuations in concentrations of bioavailable metals occur in most natural waters. In situ measurements are desirable to predict risks of adverse effects to aquatic organisms. We evaluated Diffusive Milli-Gels (DMG), a new in situ passive sampler, for assessing the bioavailability and toxicity of copper in waters exhibiting a wide range of characteristics. The performance was compared to an established Chelex-column method that measures labile copper concentrations by discrete sampling, and the ability to predict acute toxicity to the cladoceran, Ceriodaphnia dubia. The labile copper concentrations measured by the DMG and Chelex-column methods decreased with increasing dissolved organic carbon (DOC) (1.9-15 mg L -1 ) and hardness (21-270 mg CaCO 3  L -1 hardness), with 20-70% of total dissolved copper being present as labile copper. Toxicity decreased with increasing DOC and hardness. Strong linear relationships existed between the EC50 for C. dubia and DOC, and when the EC50 was related to either the labile copper concentrations measured by DMG (r 2  = 0.874) or the Chelex column (0.956) methods. The study demonstrates that the DMG passive sampler is a relevant tool for the in situ assessment of environmental risks posed by metals whose toxicity is strongly influenced by speciation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Magnetic Catheter Manipulation in the Interventional MRI Environment

PubMed Central

Wilson, Mark W.; Martin, Alastair B.; Lillaney, Prasheel; Losey, Aaron D.; Yee, Erin J.; Bernhardt, Anthony; Malba, Vincent; Evans, Lee; Sincic, Ryan; Saeed, Maythem; Arenson, Ronald L.; Hetts, Steven W.

2013-01-01

Purpose To evaluate deflection capability of a prototype endovascular catheter, which is remotely magnetically steerable, for use in the interventional MRI environment. Materials and Methods Copper coils were mounted on the tips of commercially available 2.3 – 3.0 Fr microcatheters. The coils were fabricated in a novel manner by plasma vapor deposition of a copper layer followed by laser lithography of the layer into coils. Orthogonal helical (solenoid) and saddle-shaped (Helmholtz) coils were mounted on a single catheter tip. Microcatheters were tested in water bath phantoms in a 1.5T clinical MRI scanner, with variable simultaneous currents applied to the coils. Catheter tip deflection was imaged in the axial plane utilizing a “real-time” steady-state free precession (SSFP) MRI sequence. Degree of deflection and catheter tip orientation were measured for each current application. Results The catheter tip was clearly visible in the longitudinal and axial planes. Magnetic field artifacts were visible when the orthogonal coils at the catheter tip were energized. Variable amounts of current applied to a single coil demonstrated consistent catheter deflection in all water bath experiments. Changing current polarity reversed the observed direction of deflection, whereas current applied to two different coils resulted in deflection represented by the composite vector of individual coil activations. Microcatheter navigation through the vascular phantom was successful through control of applied current to one or more coils. Conclusion Controlled catheter deflection is possible with laser lithographed multi-axis coil tipped catheters in the MRI environment. PMID:23707097

Formation of Copper Sulfide Precipitate in Solid Iron

NASA Astrophysics Data System (ADS)

Urata, Kentaro; Kobayashi, Yoshinao

The growth rate of copper sulfide precipitates has been measured in low carbon steel samples such as Fe-0.3mass%Cu-0.03mass%S-0.1mass%C and Fe-0.1mass%Cu-0.01mass%S- 0.1mass%C. Heat-treatment of the samples was conducted at 1273, 1423 and 1573 K for 100 s - 14.4 ks for precipitation of copper sulfides and then the samples were observed by a scanning electron microscope and a transmission electron microscope to measure the diameter of copper sulfides precipitated in the samples. The growth rate of copper sulfide has been found to be well described by the Ostwald growth model, as follows: R\

Verification and calibration of laser Doppler flowmetry (LDF) prototype for measurement of microcirculation

NASA Astrophysics Data System (ADS)

Li, Yung-Hui; Hu, Chia-Ming; Tsai, Ming-Lun

2017-10-01

Laser Doppler Flowmetry (LDF), a non-invasive microcirculation measurement equipment, is designed to be used in measuring microcirculation and perfusion in the skin. LDF is very applicable to healthcare. However, the cost of commercial LDF prevents its prevalence and popularity. In this paper, continuing previous researches, a LDF prototype was built from the combination of the off-the-shelf electronic components. The raw signals acquired from the proposed LDF prototype is validated to be relevant to the microcirculation flux. Furthermore, we would like to verify the consistency between the signals measured from both model, and find an implicit transformation rule to transform the LDF prototype signals. For the purpose of verification and calibration of the LDF prototype signal feature, we first collected a parallel database consisting of flux signals measured by commercial and prototype LDF at the same time. Second, we extract signals with specific frequency of normalized signals as features and use these features to establish a model to allow us to map signals measured by LDF prototype to the commercial model. The result of the experiment showed that after we used the linear regression models to calibrate physiological feature, the correlation coefficient reached nearly 0.9999, which is close to a perfect positive correlation. The overall evaluation results showed that the proposed method can verify and ensure the validity of the LDF prototype. Through the proposed transformation, the flux signals measured by the proposed LDF prototype can successfully be transformed to its parallel form as if it is measured by commercial LDF.

Identification of 210Pb and 210Po in the bulk of copper samples with a low-background alpha particle counter

NASA Astrophysics Data System (ADS)

Abe, K.; Hiraide, K.; Ichimura, K.; Kishimoto, Y.; Kobayashi, K.; Kobayashi, M.; Moriyama, S.; Nakahata, M.; Norita, T.; Ogawa, H.; Sato, K.; Sekiya, H.; Takachio, O.; Takeda, A.; Tasaka, S.; Yamashita, M.; Yang, B. S.; Kim, N. Y.; Kim, Y. D.; Itow, Y.; Kanzawa, K.; Kegasa, R.; Masuda, K.; Takiya, H.; Fushimi, K.; Kanzaki, G.; Martens, K.; Suzuki, Y.; Xu, B. D.; Fujita, R.; Hosokawa, K.; Miuchi, K.; Oka, N.; Takeuchi, Y.; Kim, Y. H.; Lee, K. B.; Lee, M. K.; Fukuda, Y.; Miyasaka, M.; Nishijima, K.; Nakamura, S.

2018-03-01

We established a method to assay 210Pb and 210Po contaminations in the bulk of copper samples using a low-background alpha particle counter. The achieved sensitivity for the 210Pb and 210Po contaminations reaches a few mBq/kg. Due to this high sensitivity, the 210Pb and 210Po contaminations in oxygen free copper bulk were identified and measured for the first time. The 210Pb contaminations of our oxygen free copper samples were 17-40 mBq/kg. Based on our investigation of copper samples in each production step, the 210Pb in oxygen free copper was understood to be a small residual of an electrolysis process. This method to measure bulk contaminations of 210Pb and 210Po could be applied to other materials.

Identification of 210Pb and 210Po in the bulk of copper samples with a low-background alpha particle counter

NASA Astrophysics Data System (ADS)

Kobayashi, Kazuyoshi

2018-01-01

We established a method to assay 210Pb and 210Po contaminations in the bulk of copper samples using a low-background alpha particle counter. The achieved sensitivity for the 210Pb and 210Po contaminations reaches a few mBq/kg. Due to this high sensitivity, the 210Pb and 210Po contaminations in oxygen free copper bulk were identified and measured for the first time. The 210Pb contaminations of our oxygen free copper samples were 17-40 mBq/kg. Based on our investigation of copper samples in each production step, the 210Pb in oxygen free copper was understood to be a small residual of an electrolysis process. This method to measure bulk contaminations of 210Pb and 210Po could be applied to other materials.

Chronic copper poisoning in Angora kids.

PubMed

Belford, C J; Raven, C R; Black, H

1989-12-01

The investigation of five field cases of chronic copper poisoning in a group of 100 Angora kids is reported. Toxicity was confirmed by the demonstration of Heinz body anaemias, necrotizing liver disease, haemoglobinuric nephrosis and excessive levels of copper in blood, livers and kidneys. The dietary history of the kids is described. Tissue levels of copper and reported interactions between selenium, zinc and copper are discussed. Therapeutic and preventative measures are suggested.

Calculation of extracted ion beam particle distribution including within-extractor collisions from H-alpha Doppler shift measurements.

PubMed

Kim, Tae-Seong; Kim, Jinchoon; In, Sang Ryul; Jeong, Seung Ho

2008-02-01

Prototype long pulse ion sources are being developed and tested toward the goal of a deuterium beam extraction of 120 keV/65 A. The latest prototype source consists of a magnetic bucket plasma generator and a four-grid copper accelerator system with multicircular apertures of 568 holes. To measure the angular divergence and the ion species of the ion beam, an optical multichannel analyzer (OMA) system for a Doppler-shifted H-alpha lights was set up at the end of a gas-cell neutralizer. But the OMA data are very difficult to analyze due to a large background level on the top of the three energy peaks (coming from H(+), H(2) (+), and H(3) (+)). These background spectra in the OMA signals seem to result from partially accelerated ion beams in the accelerator. Extracted ions could undergo a premature charge exchange as the accelerator column tends to have a high hydrogen partial pressure from the unused gas from the plasma generator, resulting in a continuous background of partially accelerated beam particles at the accelerator exit. This effect is calculated by accounting for all the possible atomic collision processes and numerically summing up three ion species across the accelerator column. The collection of all the atomic reaction cross sections and the numerical summing up will be presented. The result considerably depends on the background pressure and the ion beam species ratio (H(+), H(2) (+), and H(3) (+)). This effect constitutes more than 20% of the whole particle distribution. And the energy distribution of those suffering from collisions is broad and shows a broad maximum in the vicinity of the half and the third energy region.

Second generation crystals for Laue lens applications

NASA Astrophysics Data System (ADS)

Barrière, N.; von Ballmoos, P.; Bastie, P.; Courtois, P.; Abrosimov, N. V.; Andersen, K.; Halloin, H.; Skinner, G.; Smither, R. K.

2006-06-01

A Laue lens gamma-ray telescope represents an exciting concept for a future high-energy mission. The feasibility of such a lens has been demonstrated by the CLAIRE lens prototype; since then various mission concepts featuring a Laue lens are being developed. The latest, which is also the most ambitious, is the European Gamma-Ray Imager (GRI). However, advancing from the CLAIRE prototype to a scientifically exploitable Laue lens requires still substantial research and development. First and foremost, diffracting elements (crystals) that constitute the Laue lens have to be optimized to offer the best efficiency and imaging capabilities for the resulting telescope. The characteristics of selected candidate crystals were measured at the European Synchrotron Radiation Facility on the high-energy beamline ID 15A using a beam tuned at 292 keV. The studied low mosaicity copper crystals have shown absolute reflectivity reaching 30%. These crystals are promising for the realization of a Laue lens, despite the fact that they produce a diffracted beam featuring a Gaussian intensity profile, which contributes to the spread of the focal spot. A composition gradient Si 1-x-Ge x crystal has been investigated as well, which showed a diffraction efficiency reaching 50% (disregarding absorption) - half of the theoretical maximum - that represents an absolute reflectivity around 39 %, the best that we measured at this energy to date. This gradient crystal also showed a square-shaped rocking curve that is almost the best case to minimize the spread of the focal spot. We also show that bending a gradient crystal could still enhance the focusing. Thanks to the better focusing, a factor of 2 in sensitivity improvement may be achieved.

Differentially Fed Metal Frame Antenna With Common Mode Suppression for Biomedical Smartband Applications

NASA Astrophysics Data System (ADS)

Xu, Li-Jie; Duan, Zhu

2018-04-01

This paper proposes a differentially fed metal frame antenna for biomedical smartband applications. It occupies a planar area of 40 × 20 mm, operating at 2.45-GHz industrial, scientific, and medical band. The proposed antenna is composed of an external metal frame and an internal metal box acting as ground for electronics. Through a differential feeding to two copper strips located between the metal frame and the metal box, a rectangular ring slot is excited with common mode suppression capability. The antenna prototype is designed in free space, and then adapted to on-body scenario for both repeater and transmitter cases. Additionally, the proposed differential feeding is modified to the traditional single port, demonstrating the half-size miniaturization technique. Finally, the simulated results are verified by measurement. The proposed antenna's simple structure and satisfactory performance makes it a perfect candidate for future medical smartband applications, monitoring the physiological parameters of humans for health-care purposes.

Thermal conductance modeling and characterization of the SuperCDMS-SNOLAB sub-Kelvin cryogenic system

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

Dhuley, R. C.; Hollister, M. I.; Ruschman, M. K.

The detectors of the Super Cryogenic Dark Matter Search experiment at SNOLAB (SuperCDMS SNOLAB) will operate in a seven-layered cryostat with thermal stages between room temperature and the base temperature of 15 mK. The inner three layers of the cryostat, which are to be nominally maintained at 1 K, 250 mK, and 15 mK, will be cooled by a dilution refrigerator via conduction through long copper stems. Bolted and mechanically pressed contacts, at and cylindrical, as well as exible straps are the essential stem components that will facilitate assembly/dismantling of the cryostat. These will also allow for thermal contractions/movements duringmore » cooldown of the sub-Kelvin system. To ensure that these components and their contacts meet their design thermal conductance, prototypes were fabricated and cryogenically tested. The present paper gives an overview of the SuperCDMS SNOLAB sub-Kelvin architecture and its conductance requirements. Results from the conductance measurements tests and from sub-Kelvin thermal modeling are discussed.« less

A dual-band reconfigurable Yagi-Uda antenna with diverse radiation patterns

NASA Astrophysics Data System (ADS)

Saurav, Kushmanda; Sarkar, Debdeep; Srivastava, Kumar Vaibhav

2017-07-01

In this paper, a dual-band pattern reconfigurable antenna is proposed. The antenna comprises of a dual-band complementary split ring resonators (CSRRs) loaded dipole as the driven element and two copper strips with varying lengths as parasitic segments on both sides of the driven dipole. PIN diodes are used with the parasitic elements to control their electrical length. The CSRRs loading provide a lower order mode in addition to the reference dipole mode, while the parasitic elements along with the PIN diodes are capable of switching the omni-directional radiation of the dual-band driven element to nine different configurations of radiation patterns which include bi-directional end-fire, broadside, and uni-directional end-fire in both the operating bands. A prototype of the designed antenna together with the PIN diodes and DC bias lines is fabricated to validate the concept of dual-band radiation pattern diversity. The simulation and measurement results are in good agreement. The proposed antenna can be used in wireless access points for PCS and WLAN applications.

Development of a Portable Muon Witness System

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

Aguayo Navarrete, Estanislao; Kouzes, Richard T.; Orrell, John L.

2011-01-01

Since understanding and quantifying cosmic ray induced radioactive backgrounds in copper and germanium are important to the MAJORANA DEMONSTRATOR, methods are needed for monitoring the levels of such backgrounds produced in materials being transported and processed for the experiment. This report focuses on work conducted at Pacific Northwest National Laboratory to develop a muon witness system as a one way of monitoring induced activities. The operational goal of this apparatus is to characterize cosmic ray exposure of materials. The cosmic ray flux at the Earth’s surface is composed of several types of particles, including neutrons, muons, gamma rays and protons.more » These particles induce nuclear reactions, generating isotopes that contribute to the radiological background. Underground, the main mechanism of activation is by muon produced spallation neutrons since the hadron component of cosmic rays is removed at depths greater than a few tens of meters. This is a sub-dominant contributor above ground, but muons become predominant in underground experiments. For low-background experiments cosmogenic production of certain isotopes, such as 68Ge and 60Co, must be accounted for in the background budgets. Muons act as minimum ionizing particles, depositing a fixed amount of energy per unit length in a material, and have a very high penetrating power. Using muon flux measurements as a “witness” for the hadron flux, the cosmogenic induced activity can be quantified by correlating the measured muon flux and known hadronic production rates. A publicly available coincident muon cosmic ray detector design, the Berkeley Lab Cosmic Ray Detector (BLCRD), assembled by Juniata College, is evaluated in this work. The performance of the prototype is characterized by assessing its muon flux measurements. This evaluation is done by comparing data taken in identical scenarios with other cosmic ray telescopes. The prototype is made of two plastic scintillator paddles with associated electronics to measure energy depositions in coincidence in the two paddles. For this particular application of the prototype, the measurements performed concentrated on a broad investigation of the dependence of the muon flux on depth underground. These tests were conducted inside at Building 3420/1307 and underground at Building 3425 at the Pacific Northwest National Laboratory. The second half of this report analyzes modifications to the electronics of the BLCRD to make this detector portable. Among other modifications, a battery powered version of these electronics is proposed for the final Muon Witness design.« less

Development of graphite/copper composites utilizing engineered interfaces. M.S. Thesis Final Report

NASA Technical Reports Server (NTRS)

Devincent, Sandra M.

1991-01-01

In situ measurements of graphite/copper alloy contact angles were made using the sessile drop method. The interfacial energy values obtained from these measurements were then applied to a model for the fiber matrix interfacial debonding phenomenon found in graphite/copper composites. The formation obtained from the sessile drop tests led to the development of a copper alloy that suitably wets graphite. Characterization of graphite/copper alloy interfaces subjected to elevated temperatures was conducted using Scanning Electron Microscopy, Energy Dispersive Spectroscopy, Auger Electron Spectroscopy, and X Ray Diffraction analyses. These analyses indicated that during sessile drop tests conducted at 1130 C for 1 hour, copper alloys containing greater than 0.98 at pct chromium form continuous reaction layers of approx. 10 microns in thickness. The reaction layers are adherent to the graphite surface. The copper wets the reaction layer to form a contact angle of 60 deg or less. X ray diffraction results indicate that the reaction layer is Cr3C2.

Friction Stir Welding of GR-Cop 84 for Combustion Chamber Liners

NASA Technical Reports Server (NTRS)

Russell, Carolyn K.; Carter, Robert; Ellis, David L.; Goudy, Richard

2004-01-01

GRCop-84 is a copper-chromium-niobium alloy developed by the Glenn Research Center for liquid rocket engine combustion chamber liners. GRCop-84 exhibits superior properties over conventional copper-base alloys in a liquid hydrogen-oxygen operating environment. The Next Generation Launch Technology program has funded a program to demonstrate scale-up production capabilities of GR-Cop 84 to levels suitable for main combustion chamber production for the prototype rocket engine. This paper describes a novel method of manufacturing the main combustion chamber liner. The process consists of several steps: extrude the GR-Cop 84 powder into billets, roll the billets into plates, bump form the plates into cylinder halves and friction stir weld the halves into a cylinder. The cylinder is then metal spun formed to near net liner dimensions followed by finish machining to the final configuration. This paper describes the friction stir weld process development including tooling and non-destructive inspection techniques, culminating in the successful production of a liner preform completed through spin forming.

Quench propagation in the superconducting 6 kA flexible busbars of the LHC

NASA Astrophysics Data System (ADS)

Herzog, R.; Calvi, M.; Sonnemann, F.; Pelegrin-Carcelen, J. M.

2002-05-01

Flexible superconducting cables with currents up to 6 kA will be used to power magnets individually in the insertion regions of the LHC. In case of a quench, the currents in these circuits will decay very fast (with time constants of about 200 ms) such that relatively small copper cross sections are sufficient for these busbars. Quench propagation experiments on a prototype cable and corresponding simulations led to a detailed understanding of the quench behavior of these busbars and to recommendations for the design and application of the cable. Simulations of the quench process in a multi-strand conductor led to a detailed understanding of the way current crosses from superconducting to pure copper strands and how this affects the quench propagation velocity. At nominal current (6 kA), the quench propagation velocities are high (10 m/s) and the hot spot temperature increases rapidly. In this situation, timely quench detection and energy extraction (current reduction) are vital to prevent damage of circuit components.

Direct Metal Deposition of H13 Tool Steel on Copper Alloy Substrate: Parametric Investigation

NASA Astrophysics Data System (ADS)

Imran, M. Khalid; Masood, S. H.; Brandt, Milan

2015-12-01

Over the past decade, researchers have demonstrated interest in tribology and prototyping by the laser aided material deposition process. Laser aided direct metal deposition (DMD) enables the formation of a uniform clad by melting the powder to form desired component from metal powder materials. In this research H13 tool steel has been used to clad on a copper alloy substrate using DMD. The effects of laser parameters on the quality of DMD deposited clad have been investigated and acceptable processing parameters have been determined largely through trial-and-error approaches. The relationships between DMD process parameters and the product characteristics such as porosity, micro-cracks and microhardness have been analysed using scanning electron microscope (SEM), image analysis software (ImageJ) and microhardness tester. It has been found that DMD parameters such as laser power, powder mass flow rate, feed rate and focus size have an important role in clad quality and crack formation.

R and D progress on second-generation crystals for Laue lens applications

NASA Astrophysics Data System (ADS)

Barrière, N.; von Ballmoos, P.; Bastie, P.; Courtois, P.; Abrosimov, N. V.; Andersen, K.; Buslaps, T.; Camus, T.; Halloin, H.; Jentschel, M.; Knödlseder, J.; Roudil, G.; Serre, D.; Skinner, G.

2007-09-01

The concept of a gamma-ray telescope based on a Laue lens offers the possibility to increase the sensitivity by more than an order of magnitude with respect to existing instruments. Laue lenses have been developed by our collaboration for several years : the main achievement of this R&D program was the CLAIRE lens prototype, which has successfully demonstrated the feasibility of the concept in astrophysical conditions. Since then, the endeavour has been oriented towards the development of efficient diffracting elements (crystal slabs) in order to increase both the effective area and the width of the energy bandpass focused, the aim being to step from a technological Laue lens to a scientifically exploitable lens. The latest mission concept featuring a gamma-ray lens is the European Gamma- Ray Imager (GRI) which intends to make use of the Laue lens to cover energies from 200 keV to 1300 keV. Investigations of two promising materials, low mosaicity copper and gradient concentration silicongermanium are presented in this paper. The measurements have been performed during three runs: 6 + 4 days at the European Synchrotron Radiation Facility (Grenoble, France), on beamline ID15A, using a 500 keV monochromatic beam, and 14 days on the GAMS 4 instrument of the Institute Laue Langevin (Grenoble, France) featuring a highly monochromatic beam of 517 keV. Despite it was not perfectly homogeneous, the presented copper crystal has exhibited peak reflectivity of 25 % in accordance with theoretical predictions, and a mosaicity around 26 arcsec, the ideal range for the realization of a Laue lens such as GRI. Silicon-germanium featuring a constant gradient have been measured for the very first time at 500 keV. Two samples showed a quite homogeneous reflectivity reaching 26%, which is far from the 48 % already observed in experimental crystals but a very encouraging beginning. The measured results have been used to estimate the performance of the GRI Laue lens design.

Laser-induced selective copper plating of polypropylene surface

NASA Astrophysics Data System (ADS)

Ratautas, K.; Gedvilas, M.; Stankevičiene, I.; JagminienÄ--, A.; Norkus, E.; Li Pira, N.; Sinopoli, S.; Emanuele, U.; Račiukaitis, G.

2016-03-01

Laser writing for selective plating of electro-conductive lines for electronics has several significant advantages, compared to conventional printed circuit board technology. Firstly, this method is faster and cheaper at the prototyping stage. Secondly, material consumption is reduced, because it works selectively. However, the biggest merit of this method is potentiality to produce moulded interconnect device, enabling to create electronics on complex 3D surfaces, thus saving space, materials and cost of production. There are two basic techniques of laser writing for selective plating on plastics: the laser-induced selective activation (LISA) and laser direct structuring (LDS). In the LISA method, pure plastics without any dopant (filler) can be used. In the LDS method, special fillers are mixed in the polymer matrix. These fillers are activated during laser writing process, and, in the next processing step, the laser modified area can be selectively plated with metals. In this work, both methods of the laser writing for the selective plating of polymers were investigated and compared. For LDS approach, new material: polypropylene with carbon-based additives was tested using picosecond and nanosecond laser pulses. Different laser processing parameters (laser pulse energy, scanning speed, the number of scans, pulse durations, wavelength and overlapping of scanned lines) were applied in order to find out the optimal regime of activation. Areal selectivity tests showed a high plating resolution. The narrowest width of a copper-plated line was less than 23 μm. Finally, our material was applied to the prototype of the electronic circuit board on a 2D surface.

The use of nutshell carbons in drinking water filters for removal of trace metals.

PubMed

Ahmedna, Mohamed; Marshall, Wayne E; Husseiny, Abdo A; Rao, Ramu M; Goktepe, Ipek

2004-02-01

Filtration of drinking water by point-of-use (POU) or point-of-entry (POE) systems is becoming increasingly popular in the United States. Drinking water is filtered to remove both organic and inorganic contaminants. The objective of this study was to evaluate the use of granular activated carbon from nutshells (almond, English walnut, pecan) in a POU water filtration system to determine its effectiveness in removing select, potentially toxic metal ions, namely, copper (Cu2+), lead (Pb2+) or zinc (Zn2+) found in drinking water. The nutshell-based carbon system was designated "Envirofilter" and was compared to four commercial POU systems with brand names of BRITA, Omni Filter, PUR and Teledyne Water Pik. Eight prototype "Envirofilters", consisting of individual or binary mixtures of carbons made from acid-activated almond or pecan shells and steam-activated pecan or walnut shells were constructed and evaluated for adsorption of the three metal ions. The results indicated that a binary mixture of carbons from acid-activated almond and either steam-activated pecan or walnut shells were the most effective in removing these metals from drinking water of all the POU systems evaluated. Binary mixtures of acid-activated almond shell-based carbon with either steam-activated pecan shell- or walnut shell-based carbon removed nearly 100% of lead ion, 90-95% of copper ion and 80-90% of zinc ion. Overall the performance data on the "Envirofilters" suggest that these prototypes require less carbon than commercial filters to achieve the same metal adsorption efficiency and may also be a less expensive product.

Surface structure influences contact killing of bacteria by copper

PubMed Central

Zeiger, Marco; Solioz, Marc; Edongué, Hervais; Arzt, Eduard; Schneider, Andreas S

2014-01-01

Copper kills bacteria rapidly by a mechanism that is not yet fully resolved. The antibacterial property of copper has raised interest in its use in hospitals, in place of plastic or stainless steel. On the latter surfaces, bacteria can survive for days or even weeks. Copper surfaces could thus provide a powerful accessory measure to curb nosocomial infections. We here investigated the effect of the copper surface structure on the efficiency of contact killing of Escherichia coli, an aspect which so far has received very little attention. It was shown that electroplated copper surfaces killed bacteria more rapidly than either polished copper or native rolled copper. The release of ionic copper was also more rapid from electroplated copper compared to the other materials. Scanning electron microscopy revealed that the bacteria nudged into the grooves between the copper grains of deposited copper. The findings suggest that, in terms of contact killing, more efficient copper surfaces can be engineered. PMID:24740976

Thermal conductivity and thermal expansion of graphite fiber/copper matrix composites

NASA Technical Reports Server (NTRS)

Ellis, David L.; Mcdanels, David L.

1991-01-01

The high specific conductivity of graphite fiber/copper matrix (Gr/Cu) composites offers great potential for high heat flux structures operating at elevated temperatures. To determine the feasibility of applying Gr/Cu composites to high heat flux structures, composite plates were fabricated using unidirectional and cross-plied pitch-based P100 graphite fibers in a pure copper matrix. Thermal conductivity of the composites was measured from room temperature to 1073 K, and thermal expansion was measured from room temperature to 1050 K. The longitudinal thermal conductivity, parallel to the fiber direction, was comparable to pure copper. The transverse thermal conductivity, normal to the fiber direction, was less than that of pure copper and decreased with increasing fiber content. The longitudinal thermal expansion decreased with increasing fiber content. The transverse thermal expansion was greater than pure copper and nearly independent of fiber content.

Thermal conductivity and thermal expansion of graphite fiber-reinforced copper matrix composites

NASA Technical Reports Server (NTRS)

Ellis, David L.; Mcdanels, David L.

1993-01-01

The high specific conductivity of graphite fiber/copper matrix (Gr/Cu) composites offers great potential for high heat flux structures operating at elevated temperatures. To determine the feasibility of applying Gr/Cu composites to high heat flux structures, composite plates were fabricated using unidirectional and cross-plied pitch-based P100 graphite fibers in a pure copper matrix. Thermal conductivity of the composites was measured from room temperature to 1073 K, and thermal expansion was measured from room temperature to 1050 K. The longitudinal thermal conductivity, parallel to the fiber direction, was comparable to pure copper. The transverse thermal conductivity, normal to the fiber direction, was less than that of pure copper and decreased with increasing fiber content. The longitudinal thermal expansion decreased with increasing fiber content. The transverse thermal expansion was greater than pure copper and nearly independent of fiber content.

The effects of grooming on a copper ablative coating: a six year study.

PubMed

Tribou, Melissa; Swain, Geoffrey

2017-07-01

More than 90% of US Navy Ships are coated with copper ablative paint. These ships may spend long periods of time pier-side, which makes them vulnerable to fouling. Hull grooming has been proposed as a means of maintaining the coatings in an operational condition. This study investigated the effect of grooming on a copper ablative coating exposed statically for six years. Grooming was performed weekly or monthly with controls left ungroomed. The fouling community was visually assessed, dry film thickness measurements were taken to monitor coating loss, and the copper leaching rates were measured. It was found that weekly and monthly groomed surfaces reduced fouling, and the ungroomed surfaces became fully fouled. Coating loss was similar for weekly, monthly and ungroomed surfaces. The results suggest that grooming is a viable method for maintaining copper ablative coatings in a fouling-free condition without adverse increases in the total copper output.

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

Emanuela Barzi et al.

Fermilab is developing 11 T superconducting dipole magnets for future accelerators based on Nb{sub 3}Sn conductor. Within the High Field Magnet Project, the first prototypes feature 1 meter long two-layer shell-type coils and common coils. For the former, keystoned Rutherford-type cable made of 28 Nb{sub 3}Sn strands 1 mm in diameter are used, whereas for the latter a 60-strand flat cable was chosen. Multifilamentary Nb{sub 3}Sn strands produced with various technologies by industry were used for the development and testing of the prototype cable. An experimental cabling machine with up to 28-strand capacity that has been recently purchased, installed andmore » commissioned at Fermilab, has allowed further advances in strand and cable studies. Cables of 27 and 28 strands of various structures (single strands or assemblies of sub-strands), with aspect ratios from 7 to 17, packing factors from 85 to 95%, with and without a stainless steel core were made out of Copper, NbTi, and Modified Jelly Roll (OST), Powder-in-Tube (SMI) and Internal Tin (Mitsubishi) Nb{sub 3}Sn strands. optimal parameters were determined with respect to mechanical and electrical properties, including critical current degradation, interstrand resistance, etc. Round strands of the same billets used in the cables were deformed by rolling them down to various thicknesses. Their critical current Ic was then measured and compared with that of the strands extracted from cables having different packing factors. This paper summarizes the results of such R and D efforts at Fermilab.« less

Surface Wave Metrology for Copper/Low-k Interconnects

NASA Astrophysics Data System (ADS)

Gostein, M.; Maznev, A. A.; Mazurenko, A.; Tower, J.

2005-09-01

We review recent advances in the application of laser-induced surface acoustic wave metrology to issues in copper/low-k interconnect development and manufacturing. We illustrate how the metrology technique can be used to measure copper thickness uniformity on a range of features from solid pads to arrays of lines, focusing on specific processing issues in copper electrochemical deposition (ECD) and chemical-mechanical polishing (CMP). In addition, we review recent developments in surface wave metrology for the characterization of low-k dielectric elastic modulus, including the ability to measure within-wafer uniformity of elastic modulus and to characterize porous, anisotropic films.

Role of copper oxides in contact killing of bacteria.

PubMed

Hans, Michael; Erbe, Andreas; Mathews, Salima; Chen, Ying; Solioz, Marc; Mücklich, Frank

2013-12-31

The potential of metallic copper as an intrinsically antibacterial material is gaining increasing attention in the face of growing antibiotics resistance of bacteria. However, the mechanism of the so-called "contact killing" of bacteria by copper surfaces is poorly understood and requires further investigation. In particular, the influences of bacteria-metal interaction, media composition, and copper surface chemistry on contact killing are not fully understood. In this study, copper oxide formation on copper during standard antimicrobial testing was measured in situ by spectroscopic ellipsometry. In parallel, contact killing under these conditions was assessed with bacteria in phosphate buffered saline (PBS) or Tris-Cl. For comparison, defined Cu2O and CuO layers were thermally generated and characterized by grazing incidence X-ray diffraction. The antibacterial properties of these copper oxides were tested under the conditions used above. Finally, copper ion release was recorded for both buffer systems by inductively coupled plasma atomic absorption spectroscopy, and exposed copper samples were analyzed for topographical surface alterations. It was found that there was a fairly even growth of CuO under wet plating conditions, reaching 4-10 nm in 300 min, but no measurable Cu2O was formed during this time. CuO was found to significantly inhibit contact killing, compared to pure copper. In contrast, thermally generated Cu2O was essentially as effective in contact killing as pure copper. Copper ion release from the different surfaces roughly correlated with their antibacterial efficacy and was highest for pure copper, followed by Cu2O and CuO. Tris-Cl induced a 10-50-fold faster copper ion release compared to PBS. Since the Cu2O that primarily forms on copper under ambient conditions is as active in contact killing as pure copper, antimicrobial objects will retain their antimicrobial properties even after oxide formation.

Determination of formal redox potentials in aqueous solution of copper(II) complexes with ligands having nitrogen and oxygen donor atoms and comparison with their EPR and UV-Vis spectral features.

PubMed

Tabbì, Giovanni; Giuffrida, Alessandro; Bonomo, Raffaele P

2013-11-01

Formal redox potentials in aqueous solution were determined for copper(II) complexes with ligands having oxygen and nitrogen as donor atoms. All the chosen copper(II) complexes have well-known stereochemistries (pseudo-octahedral, square planar, square-based pyramidal, trigonal bipyramidal or tetrahedral) as witnessed by their reported spectroscopic, EPR and UV-visible (UV-Vis) features, so that a rough correlation between the measured redox potential and the typical geometrical arrangement of the copper(II) complex could be established. Negative values have been obtained for copper(II) complexes in tetragonally elongated pseudo-octahedral geometries, when measured against Ag/AgCl reference electrode. Copper(II) complexes in tetrahedral environments (or flattened tetrahedral geometries) show positive redox potential values. There is a region, always in the field of negative redox potentials which groups the copper(II) complexes exhibiting square-based pyramidal arrangements. Therefore, it is suggested that a measurement of the formal redox potential could be of great help, when some ambiguities might appear in the interpretation of spectroscopic (EPR and UV-Vis) data. Unfortunately, when the comparison is made between copper(II) complexes in square-based pyramidal geometries and those in square planar environments (or a pseudo-octahedral) a little perturbed by an equatorial tetrahedral distortion, their redox potentials could fall in the same intermediate region. In this case spectroscopic data have to be handled with great care in order to have an answer about a copper complex geometrical characteristics. © 2013.

Mechanisms of charge transfer in human copper ATPases ATP7A and ATP7B.

PubMed

Tadini-Buoninsegni, Francesco; Smeazzetto, Serena

2017-04-01

ATP7A and ATP7B are Cu + -transporting ATPases of subclass IB and play a fundamental role in intracellular copper homeostasis. ATP7A/B transfer Cu + ions across the membrane from delivery to acceptor proteins without establishing a free Cu + gradient. Transfer of copper across the membrane is coupled to ATP hydrolysis. Current measurements on solid supported membranes (SSM) were performed to investigate the mechanism of copper-related charge transfer across ATP7A and ATP7B. SSM measurements demonstrated that electrogenic copper displacement occurs within ATP7A/B following addition of ATP and formation of the phosphorylated intermediate. Comparison of the time constants for cation displacement in ATP7A/B and sarcoplasmic reticulum Ca 2+ -ATPase is consistent with the slower phosphoenzyme formation in copper ATPases. Moreover, ATP-dependent copper transfer in ATP7A/B is not affected by varying the pH, suggesting that net proton counter-transport may not occur in copper ATPases. Platinum anticancer drugs activate ATP7A/B and are subjected to ATP-dependent vectorial displacement with a mechanism analogous to that of copper. © 2016 IUBMB Life, 69(4):218-225, 2017. © 2017 International Union of Biochemistry and Molecular Biology.

Forensic discrimination of copper wire using trace element concentrations.

PubMed

Dettman, Joshua R; Cassabaum, Alyssa A; Saunders, Christopher P; Snyder, Deanna L; Buscaglia, JoAnn

2014-08-19

Copper may be recovered as evidence in high-profile cases such as thefts and improvised explosive device incidents; comparison of copper samples from the crime scene and those associated with the subject of an investigation can provide probative associative evidence and investigative support. A solution-based inductively coupled plasma mass spectrometry method for measuring trace element concentrations in high-purity copper was developed using standard reference materials. The method was evaluated for its ability to use trace element profiles to statistically discriminate between copper samples considering the precision of the measurement and manufacturing processes. The discriminating power was estimated by comparing samples chosen on the basis of the copper refining and production process to represent the within-source (samples expected to be similar) and between-source (samples expected to be different) variability using multivariate parametric- and empirical-based data simulation models with bootstrap resampling. If the false exclusion rate is set to 5%, >90% of the copper samples can be correctly determined to originate from different sources using a parametric-based model and >87% with an empirical-based approach. These results demonstrate the potential utility of the developed method for the comparison of copper samples encountered as forensic evidence.

Cool or Fool? The Association Between Drinker Prototypes and Alcohol Consumption Using Multiple Time-Point Diary Assessments in Adolescent Males.

PubMed

Teunissen, Hanneke A; Spijkerman, Renske; Kuntsche, Emmanuel; Engels, Rutger C M E; Scholte, Ron H J

2017-04-16

There is still limited understanding of how different kinds of drinker prototypes are associated with adolescent drinking. This study uses the strengths of multiple time-point diary measures (enhanced validity of alcohol use measurement) to test the predictive value of abstainer, moderate and heavy drinker prototypes in social situations. We examined whether the favorability of these prototypes (i.e., "prototype evaluation"), the perceived similarity of these prototypes to one's self-image (i.e., "prototype similarity") assessed at baseline, and their interaction predict alcohol use assessed in social situations. Drinker prototypes were assessed in a baseline sample of 599 adolescents. Subsequently, a sample of 77 alcohol-using 16 to 18-year-old males reported their Friday and Saturday evening drinking behavior the next day during eight weeks (resulting in 495 daily measures). Alcohol use was assessed in the company of peers. The more adolescents perceived themselves as similar to heavy drinker prototypes the higher their alcohol consumption in social situations. The more adolescents held favorable abstainer prototypes, the lower their alcohol consumption. The interaction between prototype evaluation and similarity was not significant. By using a more reliable and valid method to assess adolescents' alcohol use, the present study showed that more "extreme" drinker prototypes (i.e., heavy drinker and abstainer prototypes) are most predictive of adolescent alcohol use in social situations. Increasing the perceived dissimilarity to heavy drinker prototypes and the favorability of abstainer prototypes may therefore be important targets in interventions aimed at reducing adolescents' alcohol consumption.

Rapid Prototyping of a High Sensitivity Graphene Based Glucose Sensor Strip.

PubMed

Tehrani, Farshad; Reiner, Lisa; Bavarian, Behzad

2015-01-01

A rapid prototyping of an inexpensive, disposable graphene and copper nanocomposite sensor strip using polymeric flexible substrate for highly sensitive and selective nonenzymatic glucose detection has been developed and tested for direct oxidization of glucose. The CuNPs were electrochemically deposited on to the graphene sheets to improve electron transfer rates and to enhance electrocatalytic activity toward glucose. The graphene based electrode with CuNPs demonstrated a high degree of sensitivity (1101.3 ± 56 μA/mM.cm2), excellent selectivity (without an interference with Ascorbic Acid, Uric Acid, Dopamine, and Acetaminophen), good stability with a linear response to glucose ranging from 0.1 mM to 0.6 mM concentration, and detection limits of 0.025 mM to 0.9 mM. Characterization of the electrodes was performed by scanning electron microscopy (FESEM and SEM). The electrochemical properties of the modified graphene electrodes were inspected by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and amperometry.

Wireless data transmission for high energy physics applications

NASA Astrophysics Data System (ADS)

Dittmeier, Sebastian; Brenner, Richard; Dancila, Dragos; Dehos, Cedric; De Lurgio, Patrick; Djurcic, Zelimir; Drake, Gary; Gonzalez Gimenez, Jose Luis; Gustafsson, Leif; Kim, Do-Won; Locci, Elizabeth; Pfeiffer, Ullrich; Röhrich, Dieter; Rydberg, Anders; Schöning, André; Siligaris, Alexandre; Soltveit, Hans Kristian; Ullaland, Kjetil; Vincent, Pierre; Rodriguez Vazquez, Pedro; Wiedner, Dirk; Yang, Shiming

2017-08-01

Silicon tracking detectors operated at high luminosity collider experiments pose a challenge for current and future readout systems regarding bandwidth, radiation, space and power constraints. With the latest developments in wireless communications, wireless readout systems might be an attractive alternative to commonly used wired optical and copper based readout architectures. The WADAPT group (Wireless Allowing Data and Power Transmission) has been formed to study the feasibility of wireless data transmission for future tracking detectors. These proceedings cover current developments focused on communication in the 60 GHz band. This frequency band offers a high bandwidth, a small form factor and an already mature technology. Motivation for wireless data transmission for high energy physics application and the developments towards a demonstrator prototype are summarized. Feasibility studies concerning the construction and operation of a wireless transceiver system have been performed. Data transmission tests with a transceiver prototype operating at even higher frequencies in the 240 GHz band are described. Data transmission at rates up to 10 Gb/s have been obtained successfully using binary phase shift keying.

Design of high-activity single-atom catalysts via n-p codoping

NASA Astrophysics Data System (ADS)

Wang, Xiaonan; Zhou, Haiyan; Zhang, Xiaoyang; Jia, Jianfeng; Wu, Haishun

2018-03-01

The large-scale synthesis of stable single-atom catalysts (SACs) in experiments remains a significant challenge due to high surface free energy of metal atom. Here, we propose a concise n-p codoping approach, and find it can not only disperse the relatively inexpensive metal, copper (Cu), onto boron (B)-doped graphene, but also result in high-activity SACs. We use CO oxidation on B/Cu codoped graphene as a prototype example, and demonstrate that: (1) a stable SAC can be formed by stronger electrostatic attraction between the metal atom (n-type Cu) and support (p-type B-doped graphene). (2) the energy barrier of the prototype CO oxidation on B/Cu codoped graphene is 0.536 eV by the Eley-Rideal mechanism. Further analysis shows that the spin selection rule can provide well theoretical insight into high activity of our suggested SAC. The concept of n-p codoping may lead to new strategy in large-scale synthesis of stable single-atom catalysts.

Design, fabrication, and high-gradient testing of an X -band, traveling-wave accelerating structure milled from copper halves

NASA Astrophysics Data System (ADS)

Argyropoulos, Theodoros; Catalan-Lasheras, Nuria; Grudiev, Alexej; Mcmonagle, Gerard; Rodriguez-Castro, Enrique; Syrachev, Igor; Wegner, Rolf; Woolley, Ben; Wuensch, Walter; Zha, Hao; Dolgashev, Valery; Bowden, Gorden; Haase, Andrew; Lucas, Thomas Geoffrey; Volpi, Matteo; Esperante-Pereira, Daniel; Rajamäki, Robin

2018-06-01

A prototype 11.994 GHz, traveling-wave accelerating structure for the Compact Linear Collider has been built, using the novel technique of assembling the structure from milled halves. The use of milled halves has many advantages when compared to a structure made from individual disks. These include the potential for a reduction in cost, because there are fewer parts, as well as a greater freedom in choice of joining technology because there are no rf currents across the halves' joint. Here we present the rf design and fabrication of the prototype structure, followed by the results of the high-power test and post-test surface analysis. During high-power testing the structure reached an unloaded gradient of 100 MV /m at a rf breakdown rate of less than 1.5 ×10-5 breakdowns /pulse /m with a 200 ns pulse. This structure has been designed for the CLIC testing program but construction from halves can be advantageous in a wide variety of applications.

Rapid Prototyping of a High Sensitivity Graphene Based Glucose Sensor Strip

PubMed Central

Tehrani, Farshad; Reiner, Lisa; Bavarian, Behzad

2015-01-01

A rapid prototyping of an inexpensive, disposable graphene and copper nanocomposite sensor strip using polymeric flexible substrate for highly sensitive and selective nonenzymatic glucose detection has been developed and tested for direct oxidization of glucose. The CuNPs were electrochemically deposited on to the graphene sheets to improve electron transfer rates and to enhance electrocatalytic activity toward glucose. The graphene based electrode with CuNPs demonstrated a high degree of sensitivity (1101.3±56 μA/mM.cm2), excellent selectivity (without an interference with Ascorbic Acid, Uric Acid, Dopamine, and Acetaminophen), good stability with a linear response to glucose ranging from 0.1 mM to 0.6 mM concentration, and detection limits of 0.025 mM to 0.9 mM. Characterization of the electrodes was performed by scanning electron microscopy (FESEM and SEM). The electrochemical properties of the modified graphene electrodes were inspected by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and amperometry. PMID:26678700

CO2 Sensors Based on Nanocrystalline SnO2 Doped with CuO

NASA Technical Reports Server (NTRS)

Xu, Jennifer C.; Hunter, Gary W.; Liu, Chung Chiun; Ward, Benjamin J.

2008-01-01

Nanocrystalline tin oxide (SnO2) doped with copper oxide (CuO) has been found to be useful as an electrical-resistance sensory material for measuring the concentration of carbon dioxide in air. SnO2 is an n-type semiconductor that has been widely used as a sensing material for detecting such reducing gases as carbon monoxide, some of the nitrogen oxides, and hydrocarbons. Without doping, SnO2 usually does not respond to carbon dioxide and other stable gases. The discovery that the electrical resistance of CuO-doped SnO2 varies significantly with the concentration of CO2 creates opportunities for the development of relatively inexpensive CO2 sensors for detecting fires and monitoring atmospheric conditions. This discovery could also lead to research that could alter fundamental knowledge of SnO2 as a sensing material, perhaps leading to the development of SnO2-based sensing materials for measuring concentrations of oxidizing gases. Prototype CO2 sensors based on CuO-doped SnO2 have been fabricated by means of semiconductor-microfabrication and sol-gel nanomaterial-synthesis batch processes that are amendable to inexpensive implementation in mass production.

Idiopathic hyperzincemia with associated copper deficiency anemia: a diagnostic dilemma.

PubMed

Merza, Hussein; Sood, Neha; Sood, Raman

2015-10-01

Prompt serum copper and zinc in addition to vitamin B12 levels should be measured in patients suffering from refractory anemia with neurological symptoms. A timely copper supplementation can help revert the hematological and possibly the neurological manifestations.

Characterization of Copper Corrosion Products in Drinking Water by Combining Electrochemical and Surface Analyses

EPA Science Inventory

This study focuses on the application of electrochemical approaches to drinking water copper corrosion problems. Applying electrochemical approaches combined with copper solubility measurements, and solid surface analysis approaches were discussed. Tafel extrapolation and Electro...

Characterization of Copper Corrosion Products Formed in Drinking Water by Combining Electrochemical and Surface Analyses

EPA Science Inventory

This study focuses on the application of electrochemical approaches to drinking water copper corrosion problems. Applying electrochemical approaches combined with copper solubility measurements, and solid surface analysis approaches were discussed. Tafel extrapolation and Electro...

Replication of self-centering optical fiber alignment structures using hot embossing

NASA Astrophysics Data System (ADS)

Ebraert, Evert; Wissmann, Markus; Barié, Nicole; Guttmann, Markus; Schneider, Marc; Kolew, Alexander; Worgull, Matthias; Beri, Stefano; Watté, Jan; Thienpont, Hugo; Van Erps, Jürgen

2016-04-01

With the demand for broadband connectivity on the rise due to various services like video-on-demand and cloud computing becoming more popular, the need for better connectivity infrastructure is high. The only future- proof option to supply this infrastructure is to deploy "fiber to the home" (FTTH) networks. One of the main difficulties with the deployment of FTTH is the vast amount of single-mode fiber (SMF) connections that need to be made. Hence there is a strong need for components which enable high performance, robust and easy-to- use SMF connectors. Since large-scale deployment is the goal, these components should be mass-producible at low cost. We discuss a rapid prototyping process on the basis of hot embossing replication of a self-centering alignment system (SCAS) based on three micro-springs, which can position a SMF independently of its diameter. This is beneficial since there is a fabrication tolerance of up to +/-1 μm on a standard G.652 SMF's diameter that can lead to losses if the outer diameter is used as a reference for alignment. The SCAS is first prototyped with deep proton writing (DPW) in polymethylmethacrylate (PMMA) after which it is glued to a copper substrate with an adhesive. Using an electroforming process, a nickel block is grown over the PMMA prototype followed by mechanical finishing to fabricate a structured nickel mould insert. Even though the mould insert shows non- ideal and rounded features it is used to create PMMA replicas of the SCAS by means of hot embossing. The SCAS possesses a central opening in which a bare SMF can be clamped, which is designed with a diameter of 121 μm. PMMA replicas are dimensionally characterized using a multisensor coordinate measurement machine and show a central opening diameter of 128.3 +/- 2.8 μm. This should be compared to the central opening diameter of the DPW prototype used for mould formation which was measured to be 120.5 μm. This shows that the electroforming and subsequent replication process is possible for complex micro-scale components and could be accurate after optimisation. We characterized the sidewall roughness of PMMA replicas using a non- contact optical profiler, resulting in a root-mean-square roughness of 48 nm over an area of 63.7 μm×47.8 μm. This low sidewall roughness is especially important in the replication of high aspect ratio structures to facilitate demoulding since the sidewalls cause the most friction with the mould insert.

Laser-Induced, Local Oxidation of Copper Nanoparticle Films During Raman Measurements

NASA Astrophysics Data System (ADS)

Hight Walker, Angela R.; Cheng, Guangjun; Calizo, Irene

2011-03-01

The optical properties of gold and silver nanoparticles and their films have been thoroughly investigated as surface enhanced Raman scattering (SERS) substrates and chemical reaction promoters. Similar to gold and silver nanoparticles, copper nanoparticles exhibit distinct plasmon absorptions in the visible region. The work on copper nanoparticles and their films is limited due to their oxidization in air. However, their high reactivity actually provides an opportunity to exploit the laser-induced thermal effect and chemical reactions of these nanoparticles. Here, we present our investigation of the local oxidation of a copper nanoparticle film induced by a visible laser source during Raman spectroscopic measurements. The copper nanoparticle film is prepared by drop-casting chemically synthesized copper colloid onto silicon oxide/silicon substrate. The local oxidation induced by visible lasers in Raman spectroscopy is monitored with the distinct scattering peaks for copper oxides. Optical microscopy and scanning electron microscopy have been used to characterize the laser-induced morphological changes in the film. The results of this oxidation process with different excitation wavelengths and different laser powers will be presented.

A study of the effects of phosphates on copper corrosion in drinking water: Copper release, electrochemical, and surface analysis approach

NASA Astrophysics Data System (ADS)

Kang, Young C.

The following work is the study to evaluate the impact of corrosion inhibitors on the copper metal in drinking water and to investigate the corrosion mechanism in the presence and absence of inhibitors. Electrochemical experiments were conducted to understand the effect of specific corrosion inhibitors in synthetic drinking water which was prepared with controlled specific water quality parameters. Water chemistry was studied by Inductively Coupled Plasma--Atomic Emission Spectroscopy (ICP--AES) to investigate the copper leaching rate with time. Surface morphology, crystallinity of corrosion products, copper oxidation status, and surface composition were characterized by various solid surface analysis methods, such as Scanning Electron Microscopy/Energy--Dispersive Spectrometry (SEM/EDS), Grazing-Incidence-angle X-ray Diffraction (GIXRD), X-ray Photoelectron Spectroscopy (XPS), and Time-of-Flight Secondary Ions Mass Spectrometry (ToF-SIMS). The purpose of the first set of experiments was to test various electrochemical techniques for copper corrosion for short term before studying a long term loop system. Surface analysis techniques were carried out to identify and study the corrosion products that form on the fresh copper metal surface when copper coupons were exposed to test solutions for 2 days of experiments time. The second phase of experiments was conducted with a copper pipe loop system in a synthetic tap water over an extended period of time, i.e., 4 months. Copper release and electrochemically measured corrosion activity profiles were monitored carefully with and without corrosion inhibitor, polyphosphate. A correlation between the copper released into the solution and the electrochemically measured corrosion activities was also attempted. To investigate corrosion products on the copper pipe samples, various surface analysis techniques were applied in this study. Especially, static mass spectra acquisition and element distribution mapping were carried out by ToF-SIMS. Dynamic SIMS provided shallow depth profile of corroded copper sample. The third set of the experiments was related to electrochemical noise (EN) measurement through copper coupons to pipes. Calculating corrosion rate of a metal and predicting exactly how long it lasts are problematic since the metal corrosion may be caused by combined corrosion types. Many other metals undergo not only uniform corrosion, but localized corrosion. Uniform corrosion may be conducive for copper pipe to prevent it from further severe corrosion and form passivated film, but localized corrosion causes pinhole leaks and limits the copper pipe applications. The objective of this set of experiment is to discuss the application of electrochemical noise approaches to drinking water copper corrosion problems. Specially, a fundamental description of EN is presented including a discussion of how to interpret the results and technique limitations. Although it was indicated with electrochemical analysis that the corrosion activity was affected by orthophosphate addition in the short-term test, no copper-phosphate complex or compound was found by copper surface characterization. Apparently, orthophosphate can inhibit corrosion by adsorption on the copper surface, but cannot form solid complexes with copper in such a short time, 2 days. When polyphosphate was added into recirculating copper pipe system, copper level increased and polarization resistance decreased. Greenish blue residue on the copper pipe was suspected as copper phosphate complex and corrosion inhibition mechanism was proposed.

Tear copper and its association with liver copper concentrations in six adult ewes.

PubMed Central

Schoster, J V; Stuhr, C; Kiorpes, A

1995-01-01

Tear and liver copper concentrations from 6 clinically healthy adult mixed-breed ewes were measured by Atomic Absorption Electrothermal Atomization (graphite furnace) Spectrometry and Flame Absorption Spectrometry, respectively, 7 times over 227 d to determine if their tears contained copper and if so, whether tear copper concentrations could reliably predict liver copper concentrations. To produce changes in liver copper concentration, the diet was supplemented with copper at concentrations that increased from 23 mg to 45 mg Cu/kg feed/day/sheep during the study. This regimen raised liver copper for all sheep to potentially toxic hepatic tissue concentration of greater than 500 mg/kg dry (DM) matter (tissue). The results of the study showed that copper was present in the tears of all sheep. The mean tear copper concentration showed a positive correlation with liver copper concentration (P = 0.003), increasing from 0.07 mg/kg DM at the start to 0.44 mg/kg DM at the end of the study, but could not reliably predict liver copper concentration (R2 = 0.222). PMID:7648525

Validation of a Piezoelectric Sensor Array-Based Device for Measurement of Carotid-Femoral Pulse Wave Velocity: The Philips Prototype.

PubMed

Xu, Shao-Kun; Hong, Xiang-Fei; Cheng, Yi-Bang; Liu, Chang-Yuan; Li, Yan; Yin, Bin; Wang, Ji-Guang

2018-03-01

Multiple piezoelectric pressure mechanotransducers topologized into an array might improve efficiency and accuracy in collecting arterial pressure waveforms for measurement of pulse wave velocity (PWV). In the present study, we validated a piezoelectric sensor array-based prototype (Philips) against the validated and clinically widely used Complior device (Alam Medical). We recruited 33 subjects with a wide distribution of PWV. For the validation, PWV was measured sequentially with the Complior device (four times) and the Philips prototype (three times). With the 99 paired PWV values, we investigated the agreement between the Philips prototype and the Complior device using Pearson correlation analysis and Bland-Altman plot. We also performed analysis on the determinants and reproducibility of PWV measured with both devices. The correlation coefficient for PWV measured with the two devices was 0.92 ( p < 0.0001). Compared with the Complior device, the Philips prototype slightly overestimated PWV by 0.24 (± 2 standard deviations, ± 1.91) m/s, especially when PWV was high. The correlation coefficient between the difference and the average of the Philips and Complior measurements was 0.21 ( p = 0.035). Nonetheless, they had similar determinants. Age, mean arterial pressure, and sex altogether explained 81.6 and 83.9% of the variance of PWV values measured with the Philips prototype and Complior device, respectively. When the two extremes of the three PWV values measured with the Philips prototype and the Complior device were investigated, the coefficients of variation were 8.26 and 3.26%, respectively. Compared with the Complior device, the Philips prototype had similar accuracy, determinants, and reproducibility in measuring PWV.

Local structural order and relaxation effects in metal-chalcogenide glasses

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

Saleh, Z.M.

1990-01-01

Nuclear quadrupole resonance (NQR) and nuclear magnetic resonance (NMR) have been employed to study the local structural order and the relaxation mechanisms in metal-arsenic-chalcogenide glasses for metal concentrations within the glass forming region. The glass forming region in the Cu-As-S and Cu-As-se glassy systems extends approximately to 6 and 25 at. % copper, respectively. In the composition Cu[sub x](As[sub 2/5]Ch[sub 3/5])[sub 1[minus]x], where Ch = S or Se, there is evidence of dramatic changes in the local structure as copper is added to the system. One important change is the formation of As-As bonds which are absent in As[sub 2]Ch[submore » 3]. The [sup 75]As NQR measurements indicate that the density of these bonds increases with copper concentration x. These results are consistent with the predictions of a model proposed recently to explain the local structural order in glassy metal chalcogenides. While NQR data show that arsenic atoms are threefold coordinated, EXAFs measurements have shown that copper is fourfold coordinated within the glass forming ranges in both systems. The NMR measurements confirm this result and quantitatively determine the local environment around the copper nuclei. For the naturally occurring mineral luzonite (Cu[sub 3]AsS[sub 4]) copper is fourfold coordinated. The known structure of this mineral has been used as a guide to understanding the local structure in the glasses. Copper and arsenic nuclear relaxation measurements were used to study the dynamics of these systems. The temperature and frequency dependence of the spin-lattice and spin-spin relaxation times have been carefully measured to determine the relaxation mechanisms.« less

A low complexity wireless microbial fuel cell monitor using piezoresistive sensors and impulse-radio ultra-wide-band

NASA Astrophysics Data System (ADS)

Crepaldi, M.; Chiolerio, A.; Tommasi, T.; Hidalgo, D.; Canavese, G.; Stassi, S.; Demarchi, D.; Pirri, F. C.

2013-05-01

Microbial Fuel Cells (MFCs) are energy sources which generate electrical charge thanks to bacteria metabolism. Although functionally similar to chemical fuel cells (both including reactants and two electrodes, and anode and cathode), they have substantial advantages, e.g. 1) operation at ambient temperature and pressure; 2) use of neutral electrolytes and avoidance of expensive catalysts (e.g. platinum); 3) operation using organic wastes. An MFC can be effectively used in environments where ubiquitous networking requires the wireless monitoring of energy sources. We then report on a simple monitoring system for MFC comprising an ultra-low-power Impulse-Radio Ultra-Wide-Band Transmitter (TX) operating in the low 0-960MHz band and a nanostructured piezoresistive pressure sensor connected to a discrete component digital read-out circuit. The sensor comprises an insulating matrix of polydimethylsiloxane and nanostructured multi-branched copper microparticles as conductive filler. Applied mechanical stress induces a sample deformation that modulates the mean distance between particles, i.e. the current flow. The read-out circuit encodes pressure as a pulse rate variation, with an absolute sensitivity to the generated MFC voltage. Pulses with variable repetition frequency can encode battery health: the pressure sensor can be directly connected to the cells membrane to read excessive pressure. A prototype system comprises two MFCs connected in series to power both the UWB transmitter which consumes 40μW and the read-out circuit. The two MFC generate an open circuit voltage of 1.0+/-0.1V. Each MFC prototype has a total volume of 0.34L and is formed by two circular Poly(methyl methacrylate) (PMMA) chambers (anode and cathode) separated by a cation exchange membrane. The paper reports on the prototype and measurements towards a final solution which embeds all functionalities within a MFC cell. Our solution is conceived to provide energy sources integrating energy management and health monitoring capabilities to sensor nodes which are not connected to the energy grid.

Assessing the release of copper from nanocopper-treated and conventional copper-treated lumber into marine waters I: Concentrations and rates.

PubMed

Parks, Ashley N; Cantwell, Mark G; Katz, David R; Cashman, Michaela A; Luxton, Todd P; Ho, Kay T; Burgess, Robert M

2018-03-25

Little is known about the release of metal engineered nanomaterials (ENMs) from consumer goods, including lumber treated with micronized copper. Micronized copper is a recent form of antifouling wood preservative containing nanosized copper particles for use in pressure-treated lumber. The present study investigated the concentrations released and the release rate of total copper over the course of 133 d under freshwater, estuarine, and marine salinity conditions (0, 1, 10, and 30‰) for several commercially available pressure-treated lumbers: micronized copper azole (MCA) at 0.96 and 2.4 kg/m 3 , alkaline copper quaternary (ACQ) at 0.30 and 9.6 kg/m 3 , and chromated copper arsenate (CCA) at 40 kg/m 3 . Lumber was tested as blocks and as sawdust. Overall, copper was released from all treated lumber samples. Under leaching conditions, total release ranged from 2 to 55% of the measured copper originally in the lumber, with release rate constants from the blocks of 0.03 to 2.71 (units per day). Generally, measured release and modeled equilibrium concentrations were significantly higher in the estuarine conditions compared with freshwater or marine salinities, whereas rate constants showed very limited differences between salinities. Furthermore, organic carbon was released during the leaching and demonstrated a significant relationship with released copper concentrations as a function of salinity. The results indicate that copper is released into estuarine/marine waters from multiple wood treatments including lumber amended with nanoparticle-sized copper. Environ Toxicol Chem 2018;9999:1-13. Published 2018 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America. Published 2018 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.

Idiopathic hyperzincemia with associated copper deficiency anemia: a diagnostic dilemma

PubMed Central

Merza, Hussein; Sood, Neha; Sood, Raman

2015-01-01

Key Clinical Message Prompt serum copper and zinc in addition to vitamin B12 levels should be measured in patients suffering from refractory anemia with neurological symptoms. A timely copper supplementation can help revert the hematological and possibly the neurological manifestations. PMID:26509015

Synthesis and characterization of conducting polyaniline-copper composites.

PubMed

Liu, Aijie; Bac, Luong Huu; Kim, Ji-Soon; Kim, Byoung-Kee; Kim, Jin-Chun

2013-11-01

Conducting polymer composites have many interesting physical properties and important application potentials. Suitable combinations of metal nanoparticles with conductive polymers can result in composite materials having unique physical and chemical properties that can have wide application potential in diverse areas. In this work, copper nanoparticles were fabricated by electrical explosion of wire (EEW) in solution of polyacrylic acid (PAA) and ethanol. Conductive polyaniline-copper (PANI-Cu) composites have been synthesized by in-situ polymerization of aniline in the fabricated copper suspension. Optical absorption in the UV-visible region of these suspensions was measured in the range of 200-900 nm. Morphology and structure of the composites were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier-transform infrared spectra (FTIR). Pure copper nanoparticles were uniformly dispersed into the polymer matrix. Thermal stability of the composites was characterized by thermogravimetric analysis (TGA). Electrical conductivity measurements indicated that the conductivity of the composites was higher than that of pure polyaniline and increased with increasing content of copper.

Measurements of copper ground-state and metastable level population densities in a copper-chloride laser

NASA Technical Reports Server (NTRS)

Nerheim, N. M.

1977-01-01

The population densities of both the ground and the 2D(5/2) metastable states of copper atoms in a double-pulsed copper-chloride laser are correlated with laser energy as a function of time after the dissociation current pulse. Time-resolved density variations of the ground and excited copper atoms were derived from measurements of optical absorption at 324.7 and 510.6 nm, respectively, over a wide range of operating conditions in laser tubes with diameters of 4 to 40 mm. The minimum delay between the two current pulses at which lasing was observed is shown to be a function of the initial density and subsequent decay of the metastable state. Similarly, the maximum delay is shown to be a function of the initial density and decay of the ground state.

Magnetic catheter manipulation in the interventional MR imaging environment.

PubMed

Wilson, Mark W; Martin, Alastair B; Lillaney, Prasheel; Losey, Aaron D; Yee, Erin J; Bernhardt, Anthony; Malba, Vincent; Evans, Lee; Sincic, Ryan; Saeed, Maythem; Arenson, Ronald L; Hetts, Steven W

2013-06-01

To evaluate deflection capability of a prototype endovascular catheter, which is remotely magnetically steerable, for use in the interventional magnetic resonance (MR) imaging environment. Copper coils were mounted on the tips of commercially available 2.3-3.0-F microcatheters. The coils were fabricated in a novel manner by plasma vapor deposition of a copper layer followed by laser lithography of the layer into coils. Orthogonal helical (ie, solenoid) and saddle-shaped (ie, Helmholtz) coils were mounted on a single catheter tip. Microcatheters were tested in water bath phantoms in a 1.5-T clinical MR scanner, with variable simultaneous currents applied to the coils. Catheter tip deflection was imaged in the axial plane by using a "real-time" steady-state free precession MR imaging sequence. Degree of deflection and catheter tip orientation were measured for each current application. The catheter tip was clearly visible in the longitudinal and axial planes. Magnetic field artifacts were visible when the orthogonal coils at the catheter tip were energized. Variable amounts of current applied to a single coil demonstrated consistent catheter deflection in all water bath experiments. Changing current polarity reversed the observed direction of deflection, whereas current applied to two different coils resulted in deflection represented by the composite vector of individual coil activations. Microcatheter navigation through the vascular phantom was successful through control of applied current to one or more coils. Controlled catheter deflection is possible with laser lithographed multiaxis coil-tipped catheters in the MR imaging environment. Copyright © 2013 SIR. Published by Elsevier Inc. All rights reserved.

Microstructural Evolution and Mechanical Property Development of Selective Laser Melted Copper Alloys

NASA Astrophysics Data System (ADS)

Ventura, Anthony Patrick

Selective Laser Melting (SLM) is an additive manufacturing technology that utilizes a high-power laser to melt metal powder and form a part layer-by-layer. Over the last 25 years, the technology has progressed from prototyping polymer parts to full scale production of metal component. SLM offers several advantages over traditional manufacturing techniques; however, the current alloy systems that are researched and utilized for SLM do not address applications requiring high electrical and thermal conductivity. This work presents a characterization of the microstructural evolution and mechanical property development of two copper alloys fabricated via SLM and post-process heat treated to address this gap in knowledge. Tensile testing, conductivity measurement, and detailed microstructural characterization was carried out on samples in the as-printed and heat treated conditions. A single phase solid solution strengthened binary alloy, Cu-4.3Sn, was the first alloy studied. Components were selectively laser melted from pre-alloyed Cu-4.3Sn powder and heat treated at 873 K (600 °C) and 1173 K (900 °C) for 1 hour. As-printed samples were around 97 percent dense with a yield strength of 274 MPa, an electrical conductivity of 24.1 %IACS, and an elongation of 5.6%. Heat treatment resulted in lower yield strength with significant increases in ductility due to recrystallization and a decrease in dislocation density. Tensile sample geometry and surface finish also showed a significant effect on measured yield strength but a negligible change in measured ductility. Microstructural characterization indicated that grains primarily grow epitaxially with a sub-micron cellular solidification sub-structure. Nanometer scale tin dioxide particles identified via XRD were found throughout the structure in the tin-rich intercellular regions. The second alloy studied was a high-performance precipitation hardening Cu-Ni-Si alloy, C70250. Pre-alloyed powder was selectively laser melted to produce components around 98 percent dense with high mechanical strength and electrical conductivity. Aging heat treatments were carried out at 723 K (450 °C) directly on as-printed samples up to 128 hours. A peak yield strength of around 590 MPa could be attained with an electrical conductivity of 34.2 %IACS after 8 hours of aging. Conductivity continues to increase with further aging while the peak strength appears to be less sensitive to aging time exhibiting a broad range of time where near-peak properties exist. Nanometer-scale silicon-rich oxide particles exist throughout the material and persist during aging. Deformation twinning is observed in the peak age condition after tensile testing and several strengthening mechanisms appear to be active to varying degrees throughout aging, which accounts for the broad range of aging time where nearly the peak mechanical properties exist. The findings of this research are integral to understanding SLM copper alloys and serve as a foundation for future development of new copper alloys tailored to the SLM process.

Hepatic concentrations of copper and other metals in dogs with and without chronic hepatitis.

PubMed

Cedeño, Y; López-Alonso, M; Miranda, M

2016-12-01

Defects in copper metabolism have been described in several dog breeds, and recently, it has been suggested that changes in other essential trace elements could be involved in the pathogenesis of hepatic disease. This study measured hepatic copper accumulation and its interactions with other essential trace and toxic metals in dogs diagnosed with chronic hepatitis. Liver samples of 20 chronic hepatitis and 20 healthy dogs were collected. Samples were acid digested, and essential metals (cobalt, copper, iron, manganese, molibdenum, selenium and zinc) and toxic metals (arsenic, cadmium, mercury and lead) were analysed by inductively-coupled plasma mass spectrometry. Copper concentrations were significantly higher in dogs affected by hepatic disease than in controls. Dogs having chronic hepatitis with liver copper concentration greater than 100 mg/kg wet weight showed statistically higher cobalt, manganese and zinc concentrations than dogs having chronic hepatitis with liver copper concentrations less than 100 mg/kg wet weight and controls. Toxic metal concentrations were low - in all cases below the threshold associated with toxicity in dogs. Dogs with chronic hepatitis not only have increased concentrations of copper in the liver but also increased concentrations of cobalt, manganese and zinc; measurement of these elements may perhaps aid in diagnosis of liver disease in dogs. © 2016 British Small Animal Veterinary Association.

Role of plastic deformation in wear of copper and copper - 10-percent-aluminum alloy in cryogenic fuels

NASA Technical Reports Server (NTRS)

Bill, R. C.; Wisander, D. W.

1973-01-01

High-purity copper specimens and a copper-aluminum (10%) alloy specimen were subjected to sliding against Type 440 C in cryogenic fuel environments. It was found that virtually all wear occurred by the plastic deformation of a recrystallized layer extending to about 10 micrometers below the wear scar surface of the copper or copper alloy. The wear debris was in the form of a layered structure adhering to the exit region of the wear scar. Measurements on the high purity copper specimens indicated that the wear rate was proportional to the applied load and to the sliding velocity squared. A physical model of the wear process is proposed to account for these observations.

Prototype of NASA's Global Precipitation Measurement Mission Ground Validation System

NASA Technical Reports Server (NTRS)

Schwaller, M. R.; Morris, K. R.; Petersen, W. A.

2007-01-01

NASA is developing a Ground Validation System (GVS) as one of its contributions to the Global Precipitation Mission (GPM). The GPM GVS provides an independent means for evaluation, diagnosis, and ultimately improvement of GPM spaceborne measurements and precipitation products. NASA's GPM GVS consists of three elements: field campaigns/physical validation, direct network validation, and modeling and simulation. The GVS prototype of direct network validation compares Tropical Rainfall Measuring Mission (TRMM) satellite-borne radar data to similar measurements from the U.S. national network of operational weather radars. A prototype field campaign has also been conducted; modeling and simulation prototypes are under consideration.

Speciation and leachability of copper in mine tailings from porphyry copper mining: influence of particle size.

PubMed

Hansen, Henrik K; Yianatos, Juan B; Ottosen, Lisbeth M

2005-09-01

Mine tailing from the El Teniente-Codelco copper mine situated in VI Region of Chile was analysed in order to evaluate the mobility and speciation of copper in the solid material. Mine tailing was sampled after the rougher flotation circuits, and the copper content was measured to 1150 mg kg (-1) dry matter. This tailing was segmented into fractions of different size intervals: 0-38, 38-45, 45-53, 53-75, 75-106, 106-150, 150-212, and >212 microm, respectively. Copper content determination, sequential chemical extraction, and desorption experiments were carried out for each size interval in order to evaluate the speciation of copper. It was found that the particles of smallest size contained 50-60% weak acid leachable copper, whereas only 32% of the copper found in largest particles could be leached in weak acid. Copper oxides and carbonates were the dominating species in the smaller particles, and the larger particles contained considerable amounts of sulphides.

[Copper intake and blood levels as risk factors for atheromatous disease].

PubMed

Albala, C; Salazar, G; Vío, F; Araya, F; Feuerhacke, W; Olivares, S; Alvarez, G

1997-08-01

Copper is part of antioxidant enzymes and could have a cardiovascular protective effect. A higher cardiovascular risk has been associated with high as well as low plasma copper levels. To search for differences in copper intake and plasma levels between patients with coronary artery or cerebrovascular diseases and normal subjects. Zinc and copper intake, plasma levels and serum lipid levels were measured in 20 patients with cerebrovascular disease, 20 patients with an acute myocardial infarction and 40 subjects hospitalized for elective surgery, that served as controls. Copper and zinc intake was below recommended allowances in all subjects. Serum zinc and copper levels did not differ in the three study groups. In patients with myocardial infarction a weak correlation was found between serum copper and total cholesterol (r = 0.24; p < 0.05) and LDL cholesterol (r = 0.31; p < 0.05). No differences in copper levels were found in subjects with atherosclerosis and controls. The correlation between serum copper and cholesterol deserves further investigation.

Copper deficiency in the preterm infant of very low birthweight. Four cases and a reference range for plasma copper.

PubMed Central

Sutton, A M; Harvie, A; Cockburn, F; Farquharson, J; Logan, R W

1985-01-01

Four preterm infants of very low birthweight (less than 1500 g) developed signs of copper deficiency between age 8 and 10 weeks. All had required prolonged ventilatory support, parenteral nutrition, and nasojejunal feeding. The clinical features, which included osteoporosis, oedema, anaemia, neutropenia, and late apnoea improved when the oral copper intake was increased. Diagnosis was made more difficult because a suitable reference range for plasma copper was not available. Serial measurements of plasma copper in 39 preterm infants who had no important medical problems were used to produce a reference range for plasma copper from 30 weeks' gestation to term plus seven weeks. This information will aid recognition of hypocupraemia in the very low birthweight infant who is particularly at risk of copper deficiency. PMID:4026360

The measurement of the stacking fault energy in copper, nickel and copper-nickel alloys

NASA Technical Reports Server (NTRS)

Leighly, H. P., Jr.

1982-01-01

The relationship of hydrogen solubility and the hydrogen embrittlement of high strength, high performance face centered cubic alloys to the stacking fault energy of the alloys was investigated. The stacking fault energy is inversely related to the distance between the two partial dislocations which are formed by the dissociation of a perfect dislocation. The two partial dislocations define a stacking fault in the crystal which offers a region for hydrogen segregation. The distance between the partial dislocations is measured by weak beam, dark field transmission electron microscopy. The stacking fault energy is calculated. Pure copper, pure nickel and copper-nickel single crystals are used to determine the stacking fault energy.

Front-end Electronics for Unattended Measurement (FEUM). Prototype Test Plan

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

Conrad, Ryan C.; Morris, Scott J.; Smith, Leon E.

2015-09-16

The IAEA has requested that PNNL perform an initial set of tests on front-end electronics for unattended measurement (FEUM) prototypes. The FEUM prototype test plan details the tests to be performed, the criteria for evaluation, and the procedures used to execute the tests.

A bubble column evaporator with basic flat-plate condenser for brackish and seawater desalination.

PubMed

Schmack, Mario; Ho, Goen; Anda, Martin

2016-01-01

This paper describes the development and experimental evaluation of a novel bubble column-based humidification-dehumidification system, for small-scale desalination of saline groundwater or seawater in remote regions. A bubble evaporator prototype was built and matched with a simple flat-plate type condenser for concept assessment. Consistent bubble evaporation rates of between 80 and 88 ml per hour were demonstrated. Particular focus was on the performance of the simple condenser prototype, manufactured from rectangular polyvinylchlorid plastic pipe and copper sheet, a material with a high thermal conductivity that quickly allows for conduction of the heat energy. Under laboratory conditions, a long narrow condenser model of 1500 mm length and 100 mm width achieved condensate recovery rates of around 73%, without the need for external cooling. The condenser prototype was assessed under a range of different physical conditions, that is, external water cooling, partial insulation and aspects of air circulation, via implementing an internal honeycomb screen structure. Estimated by extrapolation, an up-scaled bubble desalination system with a 1 m2 condenser may produce around 19 l of distilled water per day. Sodium chloride salt removal was found to be highly effective with condensate salt concentrations between 70 and 135 µS. Based on findings and with the intent to reduce material cost of the system, a shorter condenser length of 750 mm for the non-cooled (passive) condenser and of 500 mm for the water-cooled condenser was considered to be equally efficient as the experimentally evaluated prototype of 1500 mm length.

Reflectometry-Ellipsometry Reveals Thickness, Growth Rate, and Phase Composition in Oxidation of Copper.

PubMed

Diaz Leon, Juan J; Fryauf, David M; Cormia, Robert D; Zhang, Min-Xian Max; Samuels, Kathryn; Williams, R Stanley; Kobayashi, Nobuhiko P

2016-08-31

The oxidation of copper is a complicated process. Copper oxide develops two stable phases at room temperature and standard pressure (RTSP): cuprous oxide (Cu2O) and cupric oxide (CuO). Both phases have different optical and electrical characteristics that make them interesting for applications such as solar cells or resistive switching devices. For a given application, it is necessary to selectively control oxide thickness and cupric/cuprous oxide phase volume fraction. The thickness and composition of a copper oxide film growing on the surface of copper widely depend on the characteristics of as-deposited copper. In this Research Article, two samples, copper films prepared by two different deposition techniques, electron-beam evaporation and sputtering, were studied. As the core part of the study, the formation of the oxidized copper was analyzed routinely over a period of 253 days using spectroscopic polarized reflectometry-spectroscopic ellipsometry (RE). An effective medium approximation (EMA) model was used to fit the RE data. The RE measurements were complemented and validated by using X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM) and X-ray diffraction (XRD). Our results show that the two samples oxidized under identical laboratory ambient conditions (RTSP, 87% average relative humidity) developed unique oxide films following an inverse-logarithmic growth rate with thickness and composition different from each other over time. Discussion is focused on the ability of RE to simultaneously extract thickness (i.e., growth rate) and composition of copper oxide films and on plausible physical mechanisms responsible for unique oxidation habits observed in the two copper samples. It appears that extended surface characteristics (i.e., surface roughness and grain boundaries) and preferential crystalline orientation of as-deposited polycrystalline copper films control the growth kinetics of the copper oxide film. Analysis based on a noncontact and nondestructive measurement, such as RE, to extract key material parameters is beneficial for conveniently understanding the oxidation process that would ultimately enable copper oxide-based devices at manufacturing scales.

Limits of the copper decoration technique for delineating of the V I boundary

NASA Astrophysics Data System (ADS)

Válek, L.; Stehlík, Š.; Orava, J.; Ďurík, M.; Šik, J.; Wágner, T.

2007-05-01

Copper decoration technique was used for detection of the vacancy interstitial (V I) boundary in Czochralski silicon crystal. We used the technique for delineating defects in silicon previously reported by Mule’Stagno [Solid State Phenom. 82 84 (2002) 753] and we enriched it by an upgraded application of copper on the silicon surface. The new procedure is based on the deposition of elementary copper on the silicon surface from the copper nitrate solution. The new method is more efficient contrary to Mule’Stagno (2002) and it also decreases environmental drain. We compared five etchants in order to optimize the delineation of the V I boundary. A defect region of the same diameter was detected by all the used etchants, supreme sensitivity was obtained with Wright's etchant. The outer diameter of the defect region observed by the copper decoration technique coincides with the V I boundary diameter measured by OISF testing and approximately coincides with the V I boundary diameter measured by COP testing. We found that the copper decoration technique delineates oxygen precipitates in silicon and we observed the dependence of V I boundary detectability on the size of the oxygen precipitates.

Properties of thermal air plasma with admixing of copper and carbon

NASA Astrophysics Data System (ADS)

Fesenko, S.; Veklich, A.; Boretskij, V.; Cressault, Y.; Gleizes, A.; Teulet, Ph

2014-11-01

This paper deals with investigations of air plasma with admixing of copper and carbon. Model plasma source unit with real breaking arc was used for the simulation of real discharges, which can be occurred during sliding of Cu-C composite electrodes on copper wire at electromotive vehicles. The complex technique of plasma property studies is developed. From one hand, the radial profiles of temperature and electron density in plasma of electric arc discharge in air between Cu-C composite and copper electrodes in air flow were measured by optical spectroscopy techniques. From another hand, the radial profiles of electric conductivity of plasma mixture were calculated by solution of energy balance equation. It was assumed that the thermal conductivity of air plasma is not depending on copper or carbon vapor admixtures. The electron density is obtained from electric conductivity profiles by calculation in assumption of local thermodynamic equilibrium in plasma. Computed in such way radial profiles of electron density in plasma of electric arc discharge in air between copper electrodes were compared with experimentally measured profiles. It is concluded that developed techniques of plasma diagnostics can be reasonably used in investigations of thermal plasma with copper and carbon vapors.

Preparation and characterization of copper oxide nanoparticles decorated carbon nanoparticles using laser ablation in liquid

NASA Astrophysics Data System (ADS)

Khashan, K. S.; Jabir, M. S.; Abdulameer, F. A.

2018-05-01

Carbon nanoparticles CNPs ecorated by copper oxide nano-sized particles would be successfully equipped using technique named pulsed laser ablation in liquid. The XRD pattern proved the presence of phases assigned to carbon and different phases of copper oxide. The chemical structure of the as-prepared nanoparticles samples was decided by Energy Dispersive Spectrum (EDS) measurement. EDS analysis results show the contents of Carbon, Oxygen and Copper in the final product. These nanoparticles were spherical shaped with a size distribution 10 to 80 nm or carbon nanoparticles and 5 to 50 nm for carbon decorated copper oxide nanoparticles, according to Transmission Electron Microscopy (TEM) images and particle-size distribution histogram. It was found that after doping with copper oxide, nanoparticles become smaller and more regular in shape. Optical absorption spectra of prepared nanoparticles were measured using UV–VIS spectroscopy. The absorption spectrum of carbon nanoparticles without doping indicates absorption peak at about 228 nm. After doping with copper oxide, absorption shows appearance of new absorption peak at about (254-264) nm, which is referred to the movement of the charge between 2p and 4s band of Cu2+ ions.

Accuracy of the radioactive copper incorporation test in the diagnosis of Wilson disease.

PubMed

Członkowska, Anna; Rodo, Maria; Wierzchowska-Ciok, Agata; Smolinski, Lukasz; Litwin, Tomasz

2018-02-08

In Wilson disease (WD), copper accumulates in the liver and other tissues because of mutations in the ATP7B copper transporter gene. Early and effective anticopper treatment is crucial. However, routine diagnostic methods based on clinical findings, copper metabolism tests, liver biopsies and DNA analyses do not always provide a conclusive diagnosis. The aim was to evaluate radioactive copper incorporation as a diagnostic test. We included cases with a diagnosis of WD supported by radiocopper testing and later, when available, confirmed by DNA analysis. Incorporation of 64 Cu was measured at 2, 24 and 48 hours following intravenous injection. Diagnostic accuracy (area under the receiver operating characteristic curve [AUC]), sensitivity, specificity and predictive value were assessed for 24 hours/2 hours and 48 hours/2 hours 64 Cu ratios and compared with serum measurements of ceruloplasmin, copper, non-ceruloplasmin-bound copper and urinary 24-hours copper excretion. Patients having two pathogenic ATP7B mutations (homozygotes/compound heterozygotes) (n = 74) had significantly lower 24 hours/2 hours and 48 hours/2 hours 64 Cu ratios than heterozygote controls (n = 21) (mean 0.14 and 0.12 vs 0.49 and 0.63, respectively; both P < .001). Of note, 24 hours/2 hours and 48 hours/2 hours 64 Cu ratios had excellent diagnostic accuracy, with AUCs approaching 1, and only 24-hours urinary copper excretion displayed similar positive features. Other copper metabolism tests studied had lower accuracy, specificity and sensitivity. The radioactive copper test had excellent diagnostic accuracy and may be useful in the evaluation of new therapies aimed at restoring ATP7B function. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Al2O3 and TiO2 atomic layer deposition on copper for water corrosion resistance.

PubMed

Abdulagatov, A I; Yan, Y; Cooper, J R; Zhang, Y; Gibbs, Z M; Cavanagh, A S; Yang, R G; Lee, Y C; George, S M

2011-12-01

Al(2)O(3) and TiO(2) atomic layer deposition (ALD) were employed to develop an ultrathin barrier film on copper to prevent water corrosion. The strategy was to utilize Al(2)O(3) ALD as a pinhole-free barrier and to protect the Al(2)O(3) ALD using TiO(2) ALD. An initial set of experiments was performed at 177 °C to establish that Al(2)O(3) ALD could nucleate on copper and produce a high-quality Al(2)O(3) film. In situ quartz crystal microbalance (QCM) measurements verified that Al(2)O(3) ALD nucleated and grew efficiently on copper-plated quartz crystals at 177 °C using trimethylaluminum (TMA) and water as the reactants. An electroplating technique also established that the Al(2)O(3) ALD films had a low defect density. A second set of experiments was performed for ALD at 120 °C to study the ability of ALD films to prevent copper corrosion. These experiments revealed that an Al(2)O(3) ALD film alone was insufficient to prevent copper corrosion because of the dissolution of the Al(2)O(3) film in water. Subsequently, TiO(2) ALD was explored on copper at 120 °C using TiCl(4) and water as the reactants. The resulting TiO(2) films also did not prevent the water corrosion of copper. Fortunately, Al(2)O(3) films with a TiO(2) capping layer were much more resilient to dissolution in water and prevented the water corrosion of copper. Optical microscopy images revealed that TiO(2) capping layers as thin as 200 Å on Al(2)O(3) adhesion layers could prevent copper corrosion in water at 90 °C for ~80 days. In contrast, the copper corroded almost immediately in water at 90 °C for Al(2)O(3) and ZnO films by themselves on copper. Ellipsometer measurements revealed that Al(2)O(3) films with a thickness of ~200 Å and ZnO films with a thickness of ~250 Å dissolved in water at 90 °C in ~10 days. In contrast, the ellipsometer measurements confirmed that the TiO(2) capping layers with thicknesses of ~200 Å on the Al(2)O(3) adhesion layers protected the copper for ~80 days in water at 90 °C. The TiO(2) ALD coatings were also hydrophilic and facilitated H(2)O wetting to copper wire mesh substrates. © 2011 American Chemical Society

Bioaccumulation Using Surrogate Samplers (Bass): Evaluation Of A Passive Sampler As An Alternative Monitoring Tool For Environmental Contaminants At The Savannah River Site

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

Paller, M.; Knox, A.; Kuhne, W.

2015-10-15

DOE sites conduct traditional environmental monitoring programs that require collecting, processing, and analyzing water, sediment, and fish samples. However, recently developed passive sampling technologies, such as Diffusive Gradient in Thin films (DGT), may measure the chemical phases that are available and toxic to organisms (the bioavailable fraction), thereby producing more accurate and economical results than traditional methods.  Our laboratory study showed that dissolved copper concentrations measured by DGT probes were strongly correlated with the uptake of copper by Lumbriculus variegatus, an aquatic worm, and with concentrations of copper measured by conventional methods.  Dissolved copper concentrations in DGT probes increased with timemore » of exposure, paralleling the increase in copper with time that ocurred in Lumbriculus.  Additional studies with a combination of seven dissolved metals showed similar results.  These findings support the use of DGT as a biomimetic monitoring tool and provide a basis for refinement of these methods for cost-effective environmental monitoring at DOE sites.« less

Lenticular nucleus hyperechogenicity in Wilson's disease reflects local copper, but not iron accumulation.

PubMed

Walter, Uwe; Skowrońska, Marta; Litwin, Tomasz; Szpak, Grażyna Maria; Jabłonka-Salach, Katarzyna; Skoloudík, David; Bulska, Ewa; Członkowska, Anna

2014-10-01

In patients with Wilson's disease (WD) transcranial brain sonography typically reveals areas of increased echogenicity (hyperechogenicity) of the lenticular nucleus (LN). Correlation with T2-hypointensity on magnetic resonance images suggested that LN hyperechogenicity in WD is caused by trace metal accumulation. Accumulation of both, copper and iron, in the brain of WD patients has been reported. The present study was designed to elucidate whether LN hyperechogenicity in WD reflects accumulation of copper or iron. Post-mortem brains of 15 WD patients and one non-WD subject were studied with ultrasonography in an investigator-blinded fashion. LN hyperechogenicity was measured planimetrically by manual tracing as well as using digitized image analysis. The putaminal copper content was determined in samples of 11 WD brains and the non-WD brains using inductively coupled plasma mass spectrometry, and iron content was assessed using flame atomic absorption spectroscopy. LN was normal on ultrasonography only in the non-WD brain, but abnormal (hyperechogenic) in all WD brains. Digitized image analysis measures of LN hyperechogenicity and, by trend, manual measures correlated with putaminal copper content (Pearson test; digitized: r = 0.77, p = 0.04; manual: r = 0.57, p = 0.051) but not with iron content (each, p > 0.18). LN hyperechogenicity measures were unrelated to age at death of patients, age at onset of WD, WD duration, age of brain specimen, serum copper or serum ceruloplasmin (each, p > 0.1). We conclude that LN hyperechogenicity in WD reflects copper, but not iron accumulation. Further studies are warranted to elucidate the use of transcranial brain sonography for monitoring therapeutic effects of chelating agents in WD patients.

Electrical wire explosion process of copper/silver hybrid nano-particle ink and its sintering via flash white light to achieve high electrical conductivity.

PubMed

Chung, Wan-Ho; Hwang, Yeon-Taek; Lee, Seung-Hyun; Kim, Hak-Sung

2016-05-20

In this work, combined silver/copper nanoparticles were fabricated by the electrical explosion of a metal wire. In this method, a high electrical current passes through the metal wire with a high voltage. Consequently, the metal wire evaporates and metal nanoparticles are formed. The diameters of the silver and copper nanoparticles were controlled by changing the voltage conditions. The fabricated silver and copper nano-inks were printed on a flexible polyimide (PI) substrate and sintered at room temperature via a flash light process, using a xenon lamp and varying the light energy. The microstructures of the sintered silver and copper films were observed using a scanning electron microscope (SEM) and a transmission electron microscope (TEM). To investigate the crystal phases of the flash-light-sintered silver and copper films, x-ray diffraction (XRD) was performed. The absorption wavelengths of the silver and copper nano-inks were measured using ultraviolet-visible spectroscopy (UV-vis). Furthermore, the resistivity of the sintered silver and copper films was measured using the four-point probe method and an alpha step. As a result, the fabricated Cu/Ag film shows a high electrical conductivity (4.06 μΩcm), which is comparable to the resistivity of bulk copper (1.68 μΩcm). In addition, the fabricated Cu/Ag nanoparticle film shows superior oxidation stability compared to the Cu nanoparticle film.

Advanced hair damage model from ultra-violet radiation in the presence of copper.

PubMed

Marsh, J M; Davis, M G; Flagler, M J; Sun, Y; Chaudhary, T; Mamak, M; McComb, D W; Williams, R E A; Greis, K D; Rubio, L; Coderch, L

2015-10-01

Damage to hair from UV exposure has been well reported in the literature and is known to be a highly complex process involving initiation via absorption of UV light followed by formation and propagation of reactive oxygen species (ROS). The objective of this work was to understand these mechanisms, explain the role of copper in accelerating the formation of ROS and identify strategies to reduce the hair damage caused by these reactive species. The location of copper in hair was measured by Transmission electron microscopy-(TEM) X-ray energy dispersive spectroscopy (XEDS) and levels measured by ICP-OES. Protein changes were measured as total protein loss via the Lowry assay, and MALDI ToF was used to identify the biomarker protein fragments. TBARS assay was used to measure lipid peroxide formation. Sensory methods and dry combing friction were used to measure hair damage due to copper and UV exposure and to demonstrate the efficacy of N,N' ethylenediamine disuccinic acid (EDDS) and histidine chelants to reduce this damage. In this work, a biomarker protein fragment formed during UV exposure is identified using mass spectrometry. This fragment originates from the calcium-binding protein S100A3. Also shown is the accelerated formation of this peptide fragment in hair containing low levels of copper absorbed from hair during washing with tap water containing copper ions. Transmission electron microscopy (TEM) X-ray energy dispersive spectroscopy (XEDS) studies indicate copper is located in the sulphur-poor endo-cuticle region, a region where the S100A3 protein is concentrated. A mechanism for formation of this peptide fragment is proposed in addition to the possible role of lipids in UV oxidation. A shampoo and conditioner containing chelants (EDDS in shampoo and histidine in conditioner) is shown to reduce copper uptake from tap water and reduce protein loss and formation of S100A3 protein fragment. In addition, the long-term consequences of UV oxidation and additional damage induced by copper are illustrated in a four-month wear study where hair was treated with a consumer relevant protocol of hair colouring treatments, UV exposure and regular shampoo and conditioning. The role of copper in accelerating UV damage to hair has been demonstrated as well as the ability of chelants such as EDDS and histidine in shampoo and conditioner products to reduce this damage. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Extraction-spectrophotometric determination of traces of gold in copper in silver, lead, blister copper, copper concentrate and anode slime with 4,4'-bis(dimethylamino)-thiobenzophenone.

PubMed

Tsukahara, I

1977-10-01

A sensitive spectrophotometric method has been developed for the determination of gold in copper, silver, lead, blister copper, copper concentrate and anode slime. Optimal conditions have been established for the extraction and determination of gold. Gold is extracted as its bromo complex with tri-n-octylamine and determined photometrically with 4,4'-bis(dimethylamino)thiobenzophenone; the absorbance of the organic phase is measured at 540 nm and the apparent molar absorptivity is about 1.2 x 10(5) 1.mole(-1). cm(-1). As little as 0.1 or 0.2 ppm of gold in these materials can be determined.

Intracellular Copper Does Not Catalyze the Formation of Oxidative DNA Damage in Escherichia coli▿

PubMed Central

Macomber, Lee; Rensing, Christopher; Imlay, James A.

2007-01-01

Because copper catalyzes the conversion of H2O2 to hydroxyl radicals in vitro, it has been proposed that oxidative DNA damage may be an important component of copper toxicity. Elimination of the copper export genes, copA, cueO, and cusCFBA, rendered Escherichia coli sensitive to growth inhibition by copper and provided forcing circumstances in which this hypothesis could be tested. When the cells were grown in medium supplemented with copper, the intracellular copper content increased 20-fold. However, the copper-loaded mutants were actually less sensitive to killing by H2O2 than cells grown without copper supplementation. The kinetics of cell death showed that excessive intracellular copper eliminated iron-mediated oxidative killing without contributing a copper-mediated component. Measurements of mutagenesis and quantitative PCR analysis confirmed that copper decreased the rate at which H2O2 damaged DNA. Electron paramagnetic resonance (EPR) spin trapping showed that the copper-dependent H2O2 resistance was not caused by inhibition of the Fenton reaction, for copper-supplemented cells exhibited substantial hydroxyl radical formation. However, copper EPR spectroscopy suggested that the majority of H2O2-oxidizable copper is located in the periplasm; therefore, most of the copper-mediated hydroxyl radical formation occurs in this compartment and away from the DNA. Indeed, while E. coli responds to H2O2 stress by inducing iron sequestration proteins, H2O2-stressed cells do not induce proteins that control copper levels. These observations do not explain how copper suppresses iron-mediated damage. However, it is clear that copper does not catalyze significant oxidative DNA damage in vivo; therefore, copper toxicity must occur by a different mechanism. PMID:17189367

Colour-Difference Measurement Method for Evaluation of Quality of Electrolessly Deposited Copper on Polymer after Laser-Induced Selective Activation

PubMed Central

Gedvilas, Mindaugas; Ratautas, Karolis; Kacar, Elif; Stankevičienė, Ina; Jagminienė, Aldona; Norkus, Eugenijus; Li Pira, Nello; Račiukaitis, Gediminas

2016-01-01

In this work a novel colour-difference measurement method for the quality evaluation of copper deposited on a polymer is proposed. Laser-induced selective activation (LISA) was performed onto the surface of the polycarbonate/acrylonitrile butadiene styrene (PC/ABS) polymer by using nanosecond laser irradiation. The laser activated PC/ABS polymer was copper plated by using the electroless copper plating (ECP) procedure. The sheet resistance measured by using a four-point probe technique was found to decrease by the power law with the colour-difference of the sample images after LISA and ECP procedures. The percolation theory of the electrical conductivity of the insulator conductor mixture has been adopted in order to explain the experimental results. The new proposed method was used to determine an optimal set of the laser processing parameters for best plating conditions. PMID:26960432

Studies on copper alloys containing chromium on the copper side phase diagram

NASA Technical Reports Server (NTRS)

Doi, T.

1984-01-01

Specimens were prepared from vacuum melted alloys of high purity vacuum melted copper and electrolytic chromium. The liquidus and eutectic point were determined by thermal analysis. The eutectic temperature is 1974.8 F and its composition is 1.28 wt% of chromium. The determination of solid solubility of chromium in copper was made by microscopic observation and electrical resistivity measurement. The solubility of chromium in solid copper is 0.6 wt% at 1050 F, 0.4 wt% at 1000 F, 0.25 wt% at 950 F, 0.17 wt% at 900 F, and 0.30 wt% at 840 F.

40 CFR 141.80 - General requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

... and copper action levels measured in samples collected at consumers' taps. (c) Lead and copper action levels. (1) The lead action level is exceeded if the concentration of lead in more than 10 percent of tap... action level is exceeded if the concentration of copper in more than 10 percent of tap water samples...

HPG operating experience at CEM-UT

NASA Astrophysics Data System (ADS)

Gully, J. H.; Aanstoos, T. A.; Nalty, K.; Walls, W. A.

1986-11-01

Design and functional features are presented for three homopolar generators (HPG) used in experiments during the last decade at the Center for Electromechanics at the University of Texas. The first, a disk-type, 10 MJ HPG, was built in 1973 as a prototype power source for fusion experiments. A second, compact HPG was built in 1980 for opening switch experiments as part of railgun research. The third device is an iron-core, full-scale, high speed bearing and brush test facility for supplying an energy density of 60 MJ/cu m. Engineering data obtained during studies of armature reactions actively cooled brushes morganite-copper graphite rim brushes, and peak currents, are summarized.

Rapid prototyping of versatile atom chips for atom interferometry applications.

NASA Astrophysics Data System (ADS)

Kasch, Brian; Squires, Matthew; Olson, Spencer; Kroese, Bethany; Imhof, Eric; Kohn, Rudolph; Stuhl, Benjamin; Schramm, Stacy; Stickney, James

2016-05-01

We present recent advances in the manipulation of ultracold atoms with ex-vacuo atom chips (i.e. atom chips that are not inside to the UHV chamber). Details will be presented of an experimental system that allows direct bonded copper (DBC) atom chips to be removed and replaced in minutes, requiring minimal re-optimization of parameters. This system has been used to create Bose-Einstein condensates, as well as magnetic waveguides with precisely tunable axial parameters, allowing double wells, pure harmonic confinement, and modified harmonic traps. We investigate the effects of higher order magnetic field contributions to the waveguide, and the implications for confined atom interferometry.

Study of High-Efficiency Motors Using Soft Magnetic Cores

NASA Astrophysics Data System (ADS)

Tokoi, Hirooki; Kawamata, Shoichi; Enomoto, Yuji

We have been developed a small and highly efficient axial gap motor whose stator core is made of a soft magnetic core. First, the loss sensitivities to various motor design parameters were evaluated using magnetic field analysis. It was found that the pole number and core dimensions had low sensitivity (≤ 2.2dB) in terms of the total loss, which is the sum of the copper loss and the iron losses in the stator core and the rotor yoke respectively. From this, we concluded that to improve the motor efficiency, it is essential to reduce the iron loss in the rotor yoke and minimize other losses. With this in mind, a prototype axial gap motor is manufactured and tested. The motor has four poles and six slots. The motor is 123mm in diameter and the axial length is 47mm. The rotor has parallel magnetized magnets and a rotor yoke with magnetic steel sheets. The maximum measured motor efficiency is 93%. This value roughly agrees with the maximum calculated efficiency of 95%.

Performance of timing resistive plate chambers with relativistic neutrons from 300 to 1500 MeV

NASA Astrophysics Data System (ADS)

Blanco, A.; Adamczewski-Musch, J.; Boretzky, K.; Cabanelas, P.; Cartegni, L.; Ferreira Marques, R.; Fonte, P.; Fruehauf, J.; Galaviz, D.; Heil, M.; Henriques, A.; Ickert, G.; Körper, D.; Lopes, L.; Palka, M.; Pereira, A.; Rossi, D.; Simon, H.; Teubig, P.; Traxler, M.; Velho, P.; Altstadt, S.; Atar, L.; Aumann, T.; Bemmerer, D.; Caesar, C.; Charpy, A.; Elekes, Z.; Fiori, E.; Gasparic, I.; Gerbig, J.; Göbel, K.; Heftrich, T.; Heine, M.; Heinz, A.; Holl, M.; Ignatov, A.; Isaak, J.; Johansson, H.; Kelic-Heil, A.; Lederer, C.; Lindberg, S.; Löher, B.; Machado, J.; Marganiec, J.; Martensson, M.; Nilsson, T.; Panin, V.; Paschalis, S.; Petri, M.; Plag, R.; Pohl, M.; Rastrepina, G.; Reifarth, R.; Reinhardt, T. P.; Röder, M.; Savran, D.; Scheit, H.; Schrock, P.; Silva, J.; Stach, D.; Strannerdahl, F.; Thies, R.; Wagner, A.; Wamers, F.; Weigand, M.

2015-02-01

A prototype composed of four resistive plate chamber layers has been exposed to quasi-monoenergetic neutrons produced from a deuteron beam of varying energy (300 to 1500 AMeV) in experiment S406 at GSI, Darmstad, Germany. Each layer, with an active area of about 2000 × 500 mm2, is made of modules containing the active gaps, all in multigap construction. Each gap is defined by 0.3 mm nylon mono-filaments positioned between 2.85 mm thick float glass electrodes. The modules are operated in avalanche mode with a non-flammable gas mixture composed of 90% C2H2F4 and 10% SF6. The signals are readout by a pick-up electrode formed by 15 copper strips (per layer), spaced at a pitch of 30 mm, connected at both sides to timing front end electronics. Measurements of the time of flight jitter of neutrons, in the mentioned energy range, point to a contribution of the resistive plate chamber in the order of 150 ps, independent of the neutron energy.

Direct measurement of adhesion energy of monolayer graphene as-grown on copper and its application to renewable transfer process.

PubMed

Yoon, Taeshik; Shin, Woo Cheol; Kim, Taek Yong; Mun, Jeong Hun; Kim, Taek-Soo; Cho, Byung Jin

2012-03-14

Direct measurement of the adhesion energy of monolayer graphene as-grown on metal substrates is important to better understand its bonding mechanism and control the mechanical release of the graphene from the substrates, but it has not been reported yet. We report the adhesion energy of large-area monolayer graphene synthesized on copper measured by double cantilever beam fracture mechanics testing. The adhesion energy of 0.72 ± 0.07 J m(-2) was found. Knowing the directly measured value, we further demonstrate the etching-free renewable transfer process of monolayer graphene that utilizes the repetition of the mechanical delamination followed by the regrowth of monolayer graphene on a copper substrate. © 2012 American Chemical Society

Study of inkjet printing as an ultra-low-cost antenna prototyping method and its application to conformal wraparound antennas for sounding rocket sub-payload

NASA Astrophysics Data System (ADS)

Maimaiti, Maimaitirebike

Inkjet printing is an attractive patterning technology that has received tremendous interest as a mass fabrication method for a variety of electronic devices due to its manufacturing exibility and low-cost feature. However, the printing facilities that are being used, especially the inkjet printer, are very expensive. This thesis introduces an extremely cost-friendly inkjet printing method using a printer that costs less than $100. In order to verify its reliability, linearly and circularly polarized (CPd) planar and conformal microstrip antennas were fabricated using this printing method, and their measurement results were compared with copper microstrip antennas. The result shows that the printed microstrip antennas have similar performances to those of the copper antennas except for lower efficiency. The effects of the conductivity and thickness of the ink layer on the antenna properties were studied, and it is found that the conductivity is the main factor affecting the radiation efficiency, though thicker ink yields more effective antennas. This thesis also presents the detailed antenna design for a sub-payload. The sub-payload is a cylindrical structure with a diameter of six inches and a height of four inches. It has four booms coming out from the surface, which are used to measure the variations of the energy flow into the upper atmosphere in and around the aurora. The sub-payload has two types of antennas: linearly polarized (LPd) S-band antennas and right-hand circularly polarized (RHCPd) GPS antennas. Each type of antenna has various requirements to be fully functional for specific research tasks. The thesis includes the design methods of each type of antenna, challenges that were confronted, and the possible solutions that were proposed. As a practical application, the inkjet printing method was conveniently applied in validating some of the antenna designs.

Effect of radiator position and mass flux on the dryer room heat transfer rate

NASA Astrophysics Data System (ADS)

Mirmanto, M.; Sulistyowati, E. D.; Okariawan, I. D. K.

A room radiator as usually used in cold countries, is actually able to be used as a heat source to dry goods, especially in the rainy season where the sun seldom shines due to much rain and cloud. Experiments to investigate effects of radiator position and mass flux on heat transfer rate were performed. This study is to determine the best position of the radiator and the optimum mass flux. The radiator used was a finned radiator made of copper pipes and aluminum fins with an overall dimension of 220 mm × 50 mm × 310 mm. The prototype room was constructed using plywood and wood frame with an overall size of 1000 mm × 1000 mm × 1000 mm. The working fluid was heated water flowing inside the radiator and air circulating naturally inside the prototype room. The nominal mass fluxes employed were 800, 900 and 1000 kg/m2 s. The water was kept at 80 °C at the radiator entrance, while the initial air temperature inside the prototype room was 30 °C. Three positions of the radiator were examined. The results show that the effect of the mass flux on the forced and free convection heat transfer rate is insignificant but the radiator position strongly affects the heat transfer rate for both forced and free convection.

An extended X-Ray absorption fine structure (exafs) study of copper (II) sulphate pentahydrate

NASA Astrophysics Data System (ADS)

Joyner, Richard W.

1980-05-01

The EXAFS spectrum of copper (II) sulphate pentahydrate has been measured using synchrotron radiation. Comparison with the results of ab initio calculation gives a mean copper-oxygen distance of 1.95 Å, in reasonable agreement with the known value of 1.97 Å. The relation between the EXAFS Debye-Waller factor and thermal parameters measured by neutron diffraction is discussed. Absence in the EXAFS spectrum of evidence for the second-nearest neighbour oxygen atoms, at Cu-O ≈ 2.4 Å, is discussed.

Assessment of the Bioaccessibility of Micronized Copper Wood on Simulated Stomach Fluid

EPA Pesticide Factsheets

The widespread use of copper-treated lumber has increased the potential for human exposure. Moreover, there is a lack of information on the fate and behavior of copper-treated wood particles following oral ingestion. In this study, the in vitro bioaccessibility of copper from copper-treated wood dust in simulated stomach fluid and DI water was determined. Three copper-treated wood products, liquid alkali copper quaternary and two micronized copper quarternary from different manufacturers, were incubated in the extraction media then fractionated by centrifugation and filtration through 0.45 ?m and 10 kDa filters. The copper concentrations from isolated fractions were measured using Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES). Total amounts of copper from each wood product were also determined using microwave-assisted acid digestion of dried wood samples and quantification using ICP-OES. The percent in vitro bioaccessible copper was between 83 and 90 % for all treated wood types. However, the percent of copper released in DI water was between 14 and 25 % for all wood products. This data suggests that copper is highly bioaccessible at low pH and may pose a potential human exposure risk upon ingestion. This dataset is associated with the following publication:Santiago-Rodrigues, L., J.L. Griggs, K. Bradham , C. Nelson , T. Luxton , W. Platten , and K. Rogers. Assessment of the bioaccessibility of micronized copper wood in synthetic stomach flu

Prototype instrument for noninvasive ultrasonic inspection and identification of fluids in sealed containers

NASA Astrophysics Data System (ADS)

Tucker, Brian J.; Diaz, Aaron A.; Eckenrode, Brian A.

2006-05-01

Government agencies and homeland security related organizations have identified the need to develop and establish a wide range of unprecedented capabilities for providing scientific and technical forensic services to investigations involving hazardous chemical, biological, and radiological materials, including extremely dangerous chemical and biological warfare agents. Pacific Northwest National Laboratory (PNNL) has developed a prototype portable, handheld, hazardous materials acoustic inspection prototype that provides noninvasive container interrogation and material identification capabilities using nondestructive ultrasonic velocity and attenuation measurements. Due to the wide variety of fluids as well as container sizes and materials encountered in various law enforcement inspection activities, the need for high measurement sensitivity and advanced ultrasonic measurement techniques were identified. The prototype was developed using a versatile electronics platform, advanced ultrasonic wave propagation methods, and advanced signal processing techniques. This paper primarily focuses on the ultrasonic measurement methods and signal processing techniques incorporated into the prototype. High bandwidth ultrasonic transducers combined with an advanced pulse compression technique allowed researchers to 1) obtain high signal-to-noise ratios and 2) obtain accurate and consistent time-of-flight (TOF) measurements through a variety of highly attenuative containers and fluid media. Results of work conducted in the laboratory have demonstrated that the prototype experimental measurement technique also provided information regarding container properties, which will be utilized in future container-independent measurements of hidden liquids.

The presence of algae mitigates the toxicity of copper-based algaecides to a nontarget organism.

PubMed

Bishop, West M; Willis, Ben E; Richardson, Robert J; Cope, W Gregory

2018-05-07

Copper-based algaecides are routinely applied to target noxious algal blooms in freshwaters. Standard toxicity testing data with copper suggest that typical concentrations used to control algae can cause deleterious acute impacts to nontarget organisms. These "clean" water experiments lack algae, which are specifically targeted in field applications of algaecides and contain competing ligands. The present research measured the influence of algae on algaecide exposure and subsequent response of the nontarget species Daphnia magna to copper sulfate and an ethanolamine-chelated copper algaecide (Captain®). Significant shifts (p < 0.05) in D. magna 48-h median lethal concentration (LC50) values were found when algae were present in exposures along with a copper salt or a chelated copper formulation. Copper sulfate 48-h LC50 values shifted from 75.3 to 317.8 and 517.8 μg Cu/L, whereas Captain increased from 353.8 to 414.2 and 588.5 μg Cu/L in no algae, 5 × 10 5 , and 5 × 10 6 cells/mL algae treatments, respectively. Larger shifts were measured with copper sulfate exposures, although Captain was less toxic to D. magna in all corresponding treatments. Captain was more effective at controlling Scenedesmus dimorphus at most concentrations, and control was inversely proportional to toxicity to D. magna. Overall, incorporating target competing ligands (i.e., algae) into standard toxicity testing is important for accurate risk assessment, and copper formulation can significantly alter algaecidal efficacy and risks to nontarget organisms. Environ Toxicol Chem 2018;9999:1-11. © 2018 SETAC. © 2018 SETAC.

Developing radiopure copper alloys for high strength low background applications

NASA Astrophysics Data System (ADS)

Suriano, A. M.; Howard, S. M.; Christofferson, C. D.; Arnquist, I. J.; Hoppe, E. W.

2018-01-01

High purity copper continues to play an important role for ultra-low-background detectors. Measurements of rare nuclear decays, e.g. neutrinoless double-beta decay, and searches for dark matter can require construction materials that have high thermal and electrical conductivity with bulk radiopurity less than one micro-Becquerel per kilogram. However, experiments currently using components constructed of radiopure electroformed copper struggle with design of structural and mechanical parts due to the physical properties of pure copper. A higher strength material which possesses many of the favorable attributes of copper yet remains radiopure is desired. A number of copper alloying candidates which may provide improved mechanical performance and adequate radiopurity were considered. Development of an electrodeposited copper-chrome alloy from additive-free electrolyte systems is discussed. The resulting material is shown to possess high strength and meets the aforementioned radiopurity goals.

Effects of copper supplement on growth and viability of strains used as starters and adjunct cultures for Emmental cheese manufacture.

PubMed

Rodríguez, L Mato; Alatossava, T

2008-10-01

To determine the effects of supplemented copper (Cu2+) on growth and viability of strains used as starters and adjunct cultures for Emmental cheese manufacture. Thirteen strains belonging to Lactobacillus delbrueckii, Lactobacillus helveticus, Lactobacillus rhamnosus, Streptococcus thermophilus or Propionibacterium freudenreichii species were exposed to various copper concentrations in the proper growth medium at relevant growth temperatures, and the effects of supplemented copper on bacterial growth and cell viability were determined by optical density and pH measurements, also by platings. Among the species considered, L. delbrueckii was the most copper resistant and S. thermophilus the most sensitive to copper. Anaerobic conditions increased this sensitivity significantly. There was also a considerable amount of variation in copper resistance at strain level. Copper resistance is both a species- and strain-dependent property and may reflect variability in copper-binding capacities by cell wall components among species and strains. In addition, the chemical state of copper may be involved. This study revealed that copper resistance is a highly variable property among starter and adjunct strains, and this variability should be considered when strains are selected for Emmental cheese manufacture.

Simulation and measurement of nanometer-scale resistivity of copper films for interconnect applications

NASA Astrophysics Data System (ADS)

Yarimbiyik, Arif Emre

2007-12-01

A highly versatile simulation program is developed and used to examine how the resistivity of thin metal films and lines increases as their dimensions approach and become smaller than the mean fee path of electrons in metals such as copper (size effect). The simulation program: (1) provides a more accurate calculation of surface scattering effects than that obtained from the usual formulation of Fuchs' theory, (2) calculates grain-boundary effects that are consistent with the theory of Mayadas and Shatzkes, (3) includes the effects of surface and grain-boundary scattering either separately or together, and (4) simulates the effect on resistivity if a surface of a film or line has a different value for the scattering parameter. The increase in resistivity with decreasing thickness of thin, evaporated copper films (approximately 10 nm to 150 nm thick) was determined from sheet resistance and film thickness measurements. Good agreement between the experimental results with those of the simulation program was obtained when the measured mean grain sizes were used by the simulation program. The mean of the grain sizes tend to decrease with decreasing film thickness and thereby increase the impact of grain-boundary scattering on the effective resistivity of the film. Estimates of the mean grain size for each film were determined from using, in combination, the electron backscatter diffraction (EBSD) and the X-ray diffraction (XRD) methods. With values for the measured change in sheet resistance with temperature of these films, it is shown that measurements of the electrical film thickness, using Matthiessen's rule, agreed to within 3 nm of the physical measurements (profilometer) of these films. Hence, Matthiessen's rule can continue to be used to measure the thickness of a copper film and, by inference, the cross-sectional area of a copper line for dimensions well below the mean free path of electrons in copper at room temperature (39 nm).

Shock induced spall fracture in polycrystalline copper

NASA Astrophysics Data System (ADS)

Mukherjee, D.; Rav, Amit; Sur, Amit; Joshi, K. D.; Gupta, Satish C.

2014-04-01

The plate impact experiments have been conducted on commercially available 99.99% pure polycrystalline samples of copper using single stage gas gun facility. The free surface velocity history of the sample plate measured using VISAR instrument is utilized to determine the dynamic yield strength and spall strength of copper. The dynamic yield strength and spall strength of polycrystalline copper sample has been determined to be 0.14 GPa and 1.32 GPa, respectively with corresponding strain rates of the order of 104/s.

The effect of copper, MDA, and accelerated aging on jet fuel thermal stability as measured by the gravimetric JFTOT

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

Pande, S.G.; Hardy, D.R.

1995-05-01

Thermally unstable jet fuels pose operational problems. In order to adequately identify such fuels, factors that realistically impact on thermal stability were examined. Evaluation was based on a quantitative method of measuring thermal stability, viz., NRL`s recently developed gravimetric JFTOT. This method gives a quantitative measurement of both the strip deposit and filterables formed. The pertinent factors examined, included the individual and interactive effects of: soluble copper, MDA (metal deactivator), and aging. The latter was accelerated to simulate field conditions of approximately six months aging at ambient temperature and pressure. The results indicate that the individual and interactive effects ofmore » copper, MDA, and accelerated aging appear to be fuel dependent. Based on the results, the three test fuels examined (one JP-8 and two JP-5s) were categorized as exhibiting very good, typical, and poor thermal stabilities, respectively. For both the very good and poor thermal stability fuels, the effect of copper in conjunction with accelerated aging did not significantly increase the total thermal deposits of the neat fuels. In contrast, for the typical thermal stability fuel, the combined effects of copper and accelerated aging, did. Furthermore, the addition of MDA prior to aging of the copper-doped, typical stability fuel significantly counteracted the adverse effect of copper and aging. A similar beneficial effect of MDA was not observed for the poor stability fuel. These results focus on the compositional differences among fuels and the need to elucidate these differences (physical and chemical) for a better understanding and prediction of their performance.« less

A Cuprous Oxide Thin Film Non-Enzymatic Glucose Sensor Using Differential Pulse Voltammetry and Other Voltammetry Methods and a Comparison to Different Thin Film Electrodes on the Detection of Glucose in an Alkaline Solution

PubMed Central

Molazemhosseini, Alireza; Liu, Chung Chiun

2018-01-01

A cuprous oxide (Cu2O) thin layer served as the base for a non-enzymatic glucose sensor in an alkaline medium, 0.1 NaOH solution, with a linear range of 50–200 mg/dL using differential pulse voltammetry (DPV) measurement. An X-ray photoelectron spectroscopy (XPS) study confirmed the formation of the cuprous oxide layer on the thin gold film sensor prototype. Quantitative detection of glucose in both phosphate-buffered saline (PBS) and undiluted human serum was carried out. Neither ascorbic acid nor uric acid, even at a relatively high concentration level (100 mg/dL in serum), interfered with the glucose detection, demonstrating the excellent selectivity of this non-enzymatic cuprous oxide thin layer-based glucose sensor. Chronoamperometry and single potential amperometric voltammetry were used to verify the measurements obtained by DPV, and the positive results validated that the detection of glucose in a 0.1 M NaOH alkaline medium by DPV measurement was effective. Nickel, platinum, and copper are commonly used metals for non-enzymatic glucose detection. The performance of these metal-based sensors for glucose detection using DPV were also evaluated. The cuprous oxide (Cu2O) thin layer-based sensor showed the best sensitivity for glucose detection among the sensors evaluated. PMID:29316652

SU-F-I-06: Evaluation of Imaging Dose for Modulation Layer Based Dual Energy Cone-Beam CT

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

Ju, Eunbin; Ahn, SoHyun; Cho, Samju

Purpose: Dual energy cone beam CT system is finding a variety of promising applications in diagnostic CT, both in imaging of endogenous materials and exogenous materials across a range of body sites. Dual energy cone beam CT system to suggest in this study acquire image by rotating 360 degree with half of the X-ray window covered using copper modulation layer. In the region that covered by modulation layer absorb the low energy X-ray by modulation layer. Relative high energy X-ray passes through the layer and contributes to image reconstruction. Dose evaluation should be carried out in order to utilize suchmore » an imaging acquirement technology for clinical use. Methods: For evaluating imaging dose of modulation layer based dual energy cone beam CT system, Prototype cone beam CT that configured X-ray tube (D054SB, Toshiba, Japan) and detector (PaxScan 2520V, Varian Medical Systems, Palo Alto, CA) is used. A range of 0.5–2.0 mm thickness of modulation layer is implemented in Monte Carlo simulation (MCNPX, ver. 2.6.0, Los Alamos National Laboratory, USA) with half of X-ray window covered. In-house phantom using in this study that has 3 cylindrical phantoms configured water, Teflon air with PMMA covered for verifying the comparability the various material in human body and is implemented in Monte Carlo simulation. The actual dose with 2.0 mm copper covered half of X-ray window is measured using Gafchromic EBT3 film with 5.0 mm bolus for compared with simulative dose. Results: Dose in phantom reduced 33% by copper modulation layer of 2.0 mm. Scattering dose occurred in modulation layer by Compton scattering effect is 0.04% of overall dose. Conclusion: Modulation layer of that based dual energy cone beam CT has not influence on unnecessary scatter dose. This study was supported by the Radiation Safety Research Programs (1305033) through the Nuclear Safety and Security Commission.« less

Cephradine as corrosion inhibitor for copper in 0.9% NaCl solution

NASA Astrophysics Data System (ADS)

Tasić, Žaklina Z.; Petrović Mihajlović, Marija B.; Radovanović, Milan B.; Simonović, Ana T.; Antonijević, Milan M.

2018-05-01

The effect of (6R,7R)-7-[[(2R)-2-amino-2-cyclohexa-1,4-dien-1-ylacetyl]amino]-3-methyl-8-oxo-5-thia-1-azobicyclo[4.2.0]oct-2-ene-2-carboxylic acid (cephradine) on corrosion behavior of copper in 0.9% NaCl solution was investigated. The electrochemical methods including the open circuit potential measurements, potentiodynamic polarization and electrochemical impedance spectroscopy measurements, scanning electron microscopy with energy dispersive X-ray spectroscopy and quantum chemical calculations were used for this investigation. According to the results obtained by potentiodynamic polarization, cephradine acts as mixed type inhibitor. Also, the results obtained by electrochemical impedance spectroscopy indicate that cephradine provides good copper protection in 0.9% NaCl solution. The inhibition efficiency of cephradine increases with increasing its concentration. The scanning electron microscopy with energy dispersive X-ray spectroscopy confirms that a protective layer is formed on the copper surface due to the adsorption of cephradine on the active sites on the copper surface. Adsorption of cephradine in 0.9% NaCl solution follows the Langmuir adsorption isotherm. Quantum chemical calculations are in agreement with results obtained by electrochemical measurements.

Interfacial thermal resistance and thermal rectification in carbon nanotube film-copper systems.

PubMed

Duan, Zheng; Liu, Danyang; Zhang, Guang; Li, Qingwei; Liu, Changhong; Fan, Shoushan

2017-03-02

Thermal rectification occurring at interfaces is an important research area, which contains deep fundamental physics and has extensive application prospects. In general, the measurement of interfacial thermal rectification is based on measuring interfacial thermal resistance (ITR). However, ITRs measured via conventional methods cannot avoid extra thermal resistance asymmetry due to the contact between the sample and the thermometer. In this study, we employed a non-contact infrared thermal imager to monitor the temperature of super-aligned carbon nanotube (CNT) films and obtain the ITRs between the CNT films and copper. The ITRs along the CNT-copper direction and the reverse direction are in the ranges of 2.2-3.6 cm 2 K W -1 and 9.6-11.9 cm 2 K W -1 , respectively. The obvious difference in the ITRs of the two directions shows a significant thermal rectification effect, and the rectifying coefficient ranges between 0.57 and 0.68. The remarkable rectification factor is extremely promising for the manufacture of thermal transistors with a copper/CNT/copper structure and further thermal logic devices. Moreover, our method could be extended to other 2-dimensional materials, such as graphene and MoS 2 , for further explorations.

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

Ovchinnikova, E. N.; Rogalev, A.; Wilhelm, F.

The local electronic structure of copper ions in a copper metaborate CuB{sub 2}O{sub 4} crystal is studied on the ESRF synchrotron using X-ray absorption polarization-dependent spectroscopy. The X-ray natural circular dichroism near the K absorption edge of copper is measured in the direction that is perpendicular to crystal axis c. The data obtained indicate the presence of hybridized p–d electronic states of copper. Theoretical calculations are used to separate the contributions of the two crystallographically nonequivalent positions of copper atoms in the unit cell of CuB{sub 2}O{sub 4} to the absorption and X-ray circular dichroism spectra of the crystal.

Radon daughter plate-out measurements at SNOLAB for polyethylene and copper

NASA Astrophysics Data System (ADS)

Stein, Matthew; Bauer, Dan; Bunker, Ray; Calkins, Rob; Cooley, Jodi; Loer, Ben; Scorza, Silvia

2018-02-01

Polyethylene and copper samples were exposed to the underground air at SNOLAB for approximately three months while several environmental factors were monitored. Predictions of the radon-daughter plate-out rate are compared to the resulting surface activities, obtained from high-sensitivity measurements of alpha emissivity using the XIA UltraLo-1800 spectrometer at Southern Methodist University. From these measurements, we determine an average 210Pb plate-out rate of 249 and 423 atoms/day/cm2 for polyethylene and copper, respectively, when exposed to radon activity concentration of 135 Bq/m3 at SNOLAB. A time-dependent model of alpha activity is discussed for these materials placed in similar environmental conditions.

Radon daughter plate-out measurements at SNOLAB for polyethylene and copper

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

Stein, Matthew; Bauer, Dan; Bunker, Ray

2018-02-01

Polyethylene and copper samples were exposed to the underground air at SNOLAB for approximately three months while several environmental factors were monitored. Predictions of the radon-daughter plate-out rate are compared to the resulting surface activities, obtained from high-sensitivity measurements of alpha emissivity using the XIA UltraLo-1800 spectrometer at SMU. From these measurements, we determine an averagemore » $$^{210}$$Pb plate-out rate of 249 and 423~atoms/day/cm$$^{2}$$ for polyethylene and copper, respectively, when exposed to radon activity of 135 Bq/m$$^{3}$$ at SNOLAB. A time-dependent model of alpha activity is discussed for these materials placed in similar environmental conditions.« less

Shock Hugoniot of single crystal copper

NASA Astrophysics Data System (ADS)

Chau, R.; Stölken, J.; Asoka-Kumar, P.; Kumar, M.; Holmes, N. C.

2010-01-01

The shock Hugoniot of single crystal copper is reported for stresses below 66 GPa. Symmetric impact experiments were used to measure the Hugoniots of three different crystal orientations of copper, [100], [110], and [111]. The photonic doppler velocimetry (PDV) diagnostic was adapted into a very high precision time of arrival detector for these experiments. The measured Hugoniots along all three crystal directions were nearly identical to the experimental Hugoniot for polycrystalline Cu. The predicted orientation dependence of the Hugoniot from molecular dynamics calculations was not observed. At the lowest stresses, the sound speed in Cu was extracted from the PDV data. The measured sound speeds are in agreement with values calculated from the elastic constants for Cu.

Effect of substituent of terpyridines on the in vitro antioxidant, antitubercular, biocidal and fluorescence studies of copper(II) complexes with clioquinol

NASA Astrophysics Data System (ADS)

Kharadi, G. J.

2014-01-01

An octahedral complexes of copper with clioquinol(CQ) and substituted terpyridine have been synthesized. The Cu(II) complexes have been characterized by elemental analyses, thermogravimetric analyses, magnetic moment measurements, FT-IR, electronic, 1H NMR and FAB mass spectra. Antimycobacterial screening of ligand and its copper compound against Mycobacterium tuberculosis shows clear enhancement in the antitubercular activity upon copper complexation. Ferric-reducing anti-oxidant power of all complexes were measured. The fluorescence spectra of complexes show red shift, which may be due to the chelation by the ligands to the metal ion. It enhances ligand ability to accept electrons and decreases the electron transition energy. The antimicrobial efficiency of the complexes were tested on five different microorganisms and showed good biological activity.

Method of accurate thickness measurement of boron carbide coating on copper foil

DOEpatents

Lacy, Jeffrey L.; Regmi, Murari

2017-11-07

A method is disclosed of measuring the thickness of a thin coating on a substrate comprising dissolving the coating and substrate in a reagent and using the post-dissolution concentration of the coating in the reagent to calculate an effective thickness of the coating. The preferred method includes measuring non-conducting films on flexible and rough substrates, but other kinds of thin films can be measure by matching a reliable film-substrate dissolution technique. One preferred method includes determining the thickness of Boron Carbide films deposited on copper foil. The preferred method uses a standard technique known as inductively coupled plasma optical emission spectroscopy (ICPOES) to measure boron concentration in a liquid sample prepared by dissolving boron carbide films and the Copper substrates, preferably using a chemical etch known as ceric ammonium nitrate (CAN). Measured boron concentration values can then be calculated.

Polyelectrolyte-mediated assembly of copper-phthalocyanine tetrasulfonate multilayers and the subsequent production of nanoparticulate copper oxide thin films.

PubMed

Chickneyan, Zarui Sara; Briseno, Alejandro L; Shi, Xiangyang; Han, Shubo; Huang, Jiaxing; Zhou, Feimeng

2004-07-01

An approach to producing films of nanometer-sized copper oxide particulates, based on polyelectrolyte-mediated assembly of the precursor, copper(II)phthalocyanine tetrasulfonate (CPTS), is described. Multilayered CPTS and polydiallyldimethylammonium chloride (PDADMAC) were alternately assembled on different planar substrates via the layer-by-layer (LbL) procedure. The growth of CPTS multilayers was monitored by UV-visible spectrometry and quartz crystal microbalance (QCM) measurements. Both the UV-visible spectra and the QCM data showed that a fixed amount of CPTS could be attached to the substrate surface for a given adsorption cycle. Cyclic voltammograms at the CPTS/PDADMAC-covered gold electrode exhibited a decrease in peak currents with the layer number, indicating that the permeability of CPTS multilayers on the electrodes had diminished. When these CPTS multilayered films were calcined at elevated temperatures, uniform thin films composed of nanoparticulate copper oxide could be produced. Ellipsometry showed that the thickness of copper oxide nanoparticulate films could be precisely tailored by varying the thickness of CPTS multilayer films. The morphology and roughness of CPTS multilayer and copper oxide thin films were characterized by atomic force microscopy. X-ray diffraction (XRD) measurements indicated that these thin films contained both CuO and Cu2O nanoparticles. The preparation of such copper oxide thin films with the use of metal complex precursors represents a new route for the synthesis of inorganic oxide films with a controlled thickness.

Thermal Measurements of Packed Copper Wire Enables Better Electric Motor

Science.gov Websites

transmittance characterization methods both parallel and perpendicular to the axis. A measurement of apparent from all three test methods indicated that the k_app of the packed copper wire was significantly higher methods for examining the thermal impact of new materials for winding structures relevant to motor

Effects of copper source and concentration on in vitro phytate phosphorus hydrolysis by phytase.

PubMed

Pang, Yanfang; Applegate, Todd J

2006-03-08

Five copper (Cu) sources were studied at pH 2.5, 5.5, and 6.5 to determine how Cu affects phytate phosphorus (PP) hydrolysis by phytase at concentrations up to 500 mg/kg diet (60 min, 40-41 degrees C). Subsequently, Cu solubility with and without sodium phytate was measured. Adding Cu inhibited PP hydrolysis at pH 5.5 and pH 6.5 (P < 0.05). This inhibition was greater with higher concentrations of Cu. Tri-basic copper chloride and copper lysinate inhibited PP hydrolysis much less than copper sulfate pentahydrate, copper chloride, and copper citrate (P < 0.05). A strong negative relationship was observed between PP hydrolysis and soluble Cu at pH 5.5 (r = -0.76, P < 0.0001) and 6.5 (r = -0.54, P < 0.0001). In conclusion, pH, Cu concentration, and source influenced PP hydrolysis by phytase in vitro and were related to the amount of soluble Cu and the formation of insoluble copper-phytin complexes.

Neutron-induced 63Ni activity and microscopic observation of copper samples exposed to the Hiroshima atomic bomb

NASA Astrophysics Data System (ADS)

Shizuma, Kiyoshi; Endo, Satoru; Shinozaki, Kenji; Fukushima, Hiroshi

2013-05-01

Fast neutron activation data for 63Ni in copper samples exposed to the Hiroshima atomic bomb are important in evaluating neutron doses to the survivors. Up to until now, accelerator mass spectrometry and liquid scintillation counting methods have been applied in 63Ni measurements and data were accumulated within 1500 m from the hypocenter. The slope of the activation curve versus distance shows reasonable agreement with the calculation result, however, data near the hypocenter are scarce. In the present work, two copper samples obtained from the Atomic bomb dome (155 m from the hypocenter) and the Bank of Japan building (392 m) were utilized in 63Ni beta-ray measurement with a Si surface barrier detector. Additionally, microscopic observation of the metal surfaces was performed for the first time. Only upper limit of 63Ni production was obtained for copper sample of the Atomic bomb dome. The result of the 63Ni measurement for Bank of Japan building show reasonable agreement with the AMS measurement and to fast neutron activation calculations based on the Dosimetry System 2002 (DS02) neutrons.

Preparation and characterization of copper-graphite composites by electrical explosion of wire in liquid.

PubMed

Bien, T N; Gul, W H; Bac, L H; Kim, J C

2014-11-01

Copper-graphite nanocomposites containing 5 vol.% graphite were prepared by a powder metallurgy route using an electrical wire explosion (EEW) in liquid method and spark plasma sintering (SPS) process. Graphite rods with a 0.3 mm diameter and copper wire with a 0.2 mm diameter were used as raw materials for EEWin liquid. To compare, a pure copper and copper-graphite mixture was also prepared. The fabricated graphite was in the form of a nanosheet, onto which copper particles were coated. Sintering was performed at 900 degrees C at a heating rate of 30 degrees C/min for 10 min and under a pressure of 70 MPa. The density of the sintered composite samples was measured by the Archimedes method. A wear test was performed by a ball-on-disc tribometer under dry conditions at room temperature in air. The presence of graphite effectively reduced the wear of composites. The copper-graphite nanocomposites prepared by EEW had lower wear rates than pure copper material and simple mixed copper-graphite.

Synthesis of polymer-stabilized monometallic Cu and bimetallic Cu/Ag nanoparticles and their surface-enhanced Raman scattering properties

NASA Astrophysics Data System (ADS)

Zhang, Danhui; Liu, Xiaoheng

2013-03-01

The present study demonstrates a facile process for the production of spherical-shaped Cu and Ag nanoparticles synthesized and stabilized by hydrazine and gelatin, respectively. Advantages of the synthetic method include its production of water dispersible copper and copper/silver nanoparticles at room temperature under no inert atmosphere. The resulting nanoparticles (copper or copper/silver) are investigated by X-ray diffraction (XRD), UV-vis spectroscopy, and transmission electron microscopy (TEM). The nanometallic dispersions were characterized by surface plasmon absorbance measuring at 420 and 572 nm for Ag and Cu nanoparticles, respectively. Transmission electron microscopy showed the formation of nanoparticles in the range of ˜10 nm (silver), and ˜30 nm (copper). The results also demonstrate that the reducing order of Cu2+/Ag+ is important for the formation of the bimetallic nanoparticles. The surface-enhanced Raman scattering effects of copper and copper/silver nanoparticles were also displayed. It was found that the enhancement ability of copper/silver nanoparticles was little higher than the copper nanoparticles.

Rapid Copper Acquisition by Developing Murine Mesothelioma: Decreasing Bioavailable Copper Slows Tumor Growth, Normalizes Vessels and Promotes T Cell Infiltration

PubMed Central

Crowe, Andrew; Jackaman, Connie; Beddoes, Katie M.; Ricciardo, Belinda; Nelson, Delia J.

2013-01-01

Copper, an essential trace element acquired through nutrition, is an important co-factor for pro-angiogenic factors including vascular endothelial growth factor (VEGF). Decreasing bioavailable copper has been used as an anti-angiogenic and anti-cancer strategy with promising results. However, the role of copper and its potential as a therapy in mesothelioma is not yet well understood. Therefore, we monitored copper levels in progressing murine mesothelioma tumors and analyzed the effects of lowering bioavailable copper. Copper levels in tumors and organs were assayed using atomic absorption spectrophotometry. Mesothelioma tumors rapidly sequestered copper at early stages of development, the copper was then dispersed throughout growing tumor tissues. These data imply that copper uptake may play an important role in early tumor development. Lowering bioavailable copper using the copper chelators, penicillamine, trientine or tetrathiomolybdate, slowed in vivo mesothelioma growth but did not provide any cures similar to using cisplatin chemotherapy or anti-VEGF receptor antibody therapy. The impact of copper lowering on tumor blood vessels and tumor infiltrating T cells was measured using flow cytometry and confocal microscopy. Copper lowering was associated with reduced tumor vessel diameter, reduced endothelial cell proliferation (reduced Ki67 expression) and lower surface ICAM/CD54 expression implying reduced endothelial cell activation, in a process similar to endothelial normalization. Copper lowering was also associated with a CD4+ T cell infiltrate. In conclusion, these data suggest copper lowering is a potentially useful anti-mesothelioma treatment strategy that slows tumor growth to provide a window of opportunity for inclusion of other treatment modalities to improve patient outcomes. PMID:24013775

Pressure pulsation in Kaplan turbines: Prototype-CFD comparison

NASA Astrophysics Data System (ADS)

Rivetti, A.; Lucino1, C.; Liscia, S.; Muguerza, D.; Avellan, F.

2012-11-01

Pressure pulsation phenomena in a large Kaplan turbine are investigated by means of numerical simulations (CFD) and prototype measurements in order to study the dynamic behavior of flow due to the blade passage and its interaction with other components of the turbine. Numerical simulations are performed with the commercial software Ansys CFX code, solving the incompressible Unsteady Reynolds-Averaged-Navier Stokes equations under a finite volume scheme. The computational domain involves the entire machine at prototype scale. Special care is taken in the discretization of the wicket gate overhang and runner blade gap. Prototype measurements are performed using pressure transducers at different locations among the wicket gate outlet and the draft tube inlet. Then, CFD results are compared with temporary signals of prototype measurements at identical locations to validate the numerical model. A detailed analysis was focused on the tip gap flow and the pressure field at the discharge ring. From a rotating reference frame perspective, it is found that the mean pressure fluctuates accordingly the wicket gate passage. Moreover, in prototype measurements the pressure frequency that reveals the presence of modulated cavitation at the discharge ring is distinguished, as also verified from the shape of erosion patches in concordance with the number of wicket gates.

Comparison of orbital volume obtained by tomography and rapid prototyping.

PubMed

Roça, Guilherme Berto; Foggiatto, José Aguiomar; Ono, Maria Cecilia Closs; Ono, Sergio Eiji; da Silva Freitas, Renato

2013-11-01

This study aims to compare orbital volume obtained by helical tomography and rapid prototyping. The study sample was composed of 6 helical tomography scans. Eleven healthy orbits were identified to have their volumes measured. The volumetric analysis with the helical tomography utilized the same protocol developed by the Plastic Surgery Unit of the Federal University of Paraná. From the CT images, 11 prototypes were created, and their respective volumes were analyzed in 2 ways: using software by SolidWorks and by direct analysis, when the prototype was filled with saline solution. For statistical analysis, the results of the volumes of the 11 orbits were considered independent. The average orbital volume measurements obtained by the method of Ono et al was 20.51 cm, the average obtained by the SolidWorks program was 20.64 cm, and the average measured using the prototype method was 21.81 cm. The 3 methods demonstrated a strong correlation between the measurements. The right and left orbits of each patient had similar volumes. The tomographic method for the analysis of orbital volume using the Ono protocol yielded consistent values, and by combining this method with rapid prototyping, both reliability validations of results were enhanced.

Thermodynamic Temperature Measurement to the Indium Point Based on Radiance Comparison

NASA Astrophysics Data System (ADS)

Yamaguchi, Y.; Yamada, Y.

2017-04-01

A multi-national project (the EMRP InK project) was completed recently, which successfully determined the thermodynamic temperatures of several of the high-temperature fixed points above the copper point. The National Metrology Institute of Japan contributed to this project with its newly established absolute spectral radiance calibration capability. In the current study, we have extended the range of thermodynamic temperature measurement to below the copper point and measured the thermodynamic temperatures of the indium point (T_{90} = 429.748 5 K), tin point (505.078 K), zinc point (692.677 K), aluminum point (933.473 K) and the silver point (1 234.93 K) by radiance comparison against the copper point, with a set of radiation thermometers having center wavelengths ranging from 0.65 μm to 1.6 μm. The copper-point temperature was measured by the absolute radiation thermometer which was calibrated by radiance method traceable to the electrical substitution cryogenic radiometer. The radiance of the fixed-point blackbodies was measured by standard radiation thermometers whose spectral responsivity and nonlinearity are precisely evaluated, and then the thermodynamic temperatures were determined from radiance ratios to the copper point. The values of T-T_{90} for the silver-, aluminum-, zinc-, tin- and indium-point cells were determined as -4 mK (U = 104 mK, k=2), -99 mK (88 mK), -76 mK (76 mK), -68 mK (163 mK) and -42 mK (279 mK), respectively.

Zinc and copper balances in healthy adult males during and after 17 wk of bed rest

NASA Technical Reports Server (NTRS)

Krebs, J. M.; Schneider, V. S.; LeBlanc, A. D.; Kuo, M. C.; Spector, E.; Lane, H. W.

1993-01-01

The effects of long-term bed rest on zinc and copper balances were measured in seven healthy men. Volunteers aged 22-54 y (mean +/- SD, 34 +/- 12 y), 168-185 cm in height (173 +/- 5 cm), and 64-86 kg in weight (74 +/- 9 kg) remained on a metabolic ward for 29 wk. Subjects were ambulatory during weeks 1-5, remained in continuous bed rest for weeks 6-22, and were reambulated during weeks 23-29. Copper and zinc were measured in weekly urine and fecal composites. Dietary intakes provided (mean +/- SD) 19.2 +/- 1.2 mumol Cu (1.22 +/- 0.08 mg), 211 +/- 11 mumol Zn (13.81 +/- 0.72 mg), 25.2 +/- 1.2 mmol Ca (1011 +/- 46 mg), 1086 +/- 46 mmol N (15.21 +/- 0.65 g), and 48.1 +/- 1.4 mmol K (1489 +/- 44 mg)/d. Bed rest increased fecal zinc excretion and decreased zinc balance, whereas copper balance was unchanged. Reambulation decreased fecal zinc excretion and increased both zinc and copper balances. These results suggest that during long-term bed rest or space flight, individuals will lose total body zinc and will retain more zinc and copper when they reambulate.

Influence of oxygen, albumin and pH on copper dissolution in a simulated uterine fluid.

PubMed

Bastidas, D M; Cano, E; Mora, E M

2005-06-01

The aim of this paper is to study the influence of albumin content, from 5 to 45 g/L, on copper dissolution and compounds composition in a simulated uterine solution. Experiments were performed in atmospheric pressure conditions and with an additional oxygen pressure of 0.2 atmospheres, at 6.3 and 8.0 pH values, and at a temperature of 37 +/- 0.1 degrees C for 1, 3, 7, and 30 days experimentation time. The copper dissolution rate has been determined using absorbance measurements, finding the highest value for pH 8.0, 35 g/L albumin, and with an additional oxygen pressure of 0.2 atmospheres: 674 microg/day for 1 day, and 301 microg/day for 30 days. X-ray photoelectron spectroscopy (XPS) results show copper(II) as the main copper oxidation state at pH 8.0; and copper(I) and metallic copper at pH 6.3. The presence of albumin up to 35 g/L, accelerates copper dissolution. For high albumin content a stabilisation on the copper dissolution takes place. Corrosion product layer morphology is poorly protective, showing paths through which copper ions can release.

Reduction of the "burst release" of copper ions from copper-based intrauterine devices by organic inhibitors.

PubMed

Alvarez, Florencia; Schilardi, Patricia L; de Mele, Monica Fernández Lorenzo

2012-01-01

The copper intrauterine device is a contraceptive method that is based on the release of copper ions from a copper wire. Immediately after insertion, the dissolution of copper in the uterine fluid is markedly higher ("burst release") than that necessary for contraception action, leading to a variety of harmful effects. Pretreatments with organic compounds [thiourea (TU) and purine (PU), 10(-4)-10(-2) M concentration range, 1- and 3-h immersion times] were tested. The dissolution of copper with and without pretreatments in TU and PU solutions was analyzed by conventional electrochemical techniques and surface analysis. Pretreatments in PU solutions reduced the initial corrosion rate of copper in simulated uterine solutions, with inhibitory efficiencies that depend on the PU concentration and on the immersion time assayed. Inhibitory efficiency values higher than 98% for pretreatments with ≥10(-3) M PU were found. Conversely, after TU pretreatments, a high copper release was measured. It was concluded that 10(-3) M PU pretreatment is a promising strategy able to reduce the "burst release" of copper and to ensure contraceptive action. Copyright © 2012 Elsevier Inc. All rights reserved.

Serum ceruloplasmin protein expression and activity increases in iron-deficient rats and is further enhanced by higher dietary copper intake

PubMed Central

Ranganathan, Perungavur N.; Lu, Yan; Jiang, Lingli; Kim, Changae

2011-01-01

Increases in serum and liver copper content are noted during iron deficiency in mammals, suggesting that copper-dependent processes participate during iron deprivation. One point of intersection between the 2 metals is the liver-derived, multicopper ferroxidase ceruloplasmin (Cp) that is important for iron release from certain tissues. The current study sought to explore Cp expression and activity during physiologic states in which hepatic copper loading occurs (eg, iron deficiency). Weanling rats were fed control or low iron diets containing low, normal, or high copper for ∼ 5 weeks, and parameters of iron homeostasis were measured. Liver copper increased in control and iron-deficient rats fed extra copper. Hepatic Cp mRNA levels did not change; however, serum Cp protein was higher during iron deprivation and with higher copper consumption. In-gel and spectrophotometric ferroxidase and amine oxidase assays demonstrated that Cp activity was enhanced when hepatic copper loading occurred. Interestingly, liver copper levels strongly correlated with Cp protein expression and activity. These observations support the possibility that liver copper loading increases metallation of the Cp protein, leading to increased production of the holo enzyme. Moreover, this phenomenon may play an important role in the compensatory response to maintain iron homeostasis during iron deficiency. PMID:21768302

Micro determination of plasma and erythrocyte copper by atomic absorption spectrophotometry

PubMed Central

Blomfield, Jeanette; Macmahon, R. A.

1969-01-01

The free and total plasma copper and total erythrocyte copper levels have been determined by simple, yet sensitive and highly specific methods, using atomic absorption spectrophotometry. For total copper determination, the copper was split from its protein combination in plasma or red cells by the action of hydrochloric acid at room temperature. The liberated copper was chelated by ammonium pyrrolidine dithiocarbamate and extracted into n-butyl acetate by shaking and the organic extract was aspirated into the atomic absorption spectrophotometer flame. The entire procedure was carried out in polypropylene centrifuge tubes, capped during shaking. For the free plasma copper measurement the hydrochloric acid step was omitted. Removal of the plasma or erythrocyte proteins was found to be unnecessary, and, in addition, the presence of trichloracetic acid caused an appreciable lowering of absorption. Using a double-beam atomic absorption spectrophotometer and scale expansion × 10, micro methods have been derived for determining the total copper of plasma or erythrocytes with 0·1 ml of sample, and the free copper of plasma with 0·5 ml. The macro plasma copper method requires 2 ml of plasma and is suitable for use with single-beam atomic absorption spectrophotometers. With blood from 50 blood donors, normal ranges of plasma and erythrocyte copper have been determined. PMID:5776543

Experimental investigation and numerical simulation of a copper micro-channel heat exchanger with HFE-7200 working fluid

NASA Astrophysics Data System (ADS)

Borquist, Eric

Ever increasing cost and consumption of global energy resources has inspired the development of energy harvesting techniques which increase system efficiency, sustainability, and environmental impact by using waste energy otherwise lost to the surroundings. As part of a larger effort to produce a multi-energy source prototype, this study focused on the fabrication and testing of a waste heat recovery micro-channel heat exchanger. Reducing cost and facility requirements were a priority for potential industry and commercial adoption of such energy harvesting devices. During development of the micro-channel heat exchanger, a new fabrication process using mature technologies was created that reduced cost, time, and required equipment. Testing involved filling the micro-channel heat exchanger with 3MTM NovecTM HFE-7200 working fluid. The working fluid was chosen for appropriate physical and environmental properties for the prototypes intended application. Using a dry heat exchanger as the baseline, the addition of the working fluid proved advantageous by increasing energy output by 8% while decreasing overall device temperatures. Upon successful experimental testing of the physical device, internal operation was determined based on implementation of the lattice Boltzmann method, a physics-based statistical method that actively tracked the phase change occurring in a simulated micro-channel. The simulation demonstrated three primary areas of phase change occurring, surfaces adjacent to where the heat source and heat sink were located and the bulk vapor-liquid interface, which agreed with initial device design intentions. Condensation film thickness grew to 5microm over the time interval, while the bulk interface tracked from initial 12microm from the lid to 20microm from the lid. Surface tension effects dominating vapor pressure kept the liquid near the heat source; however, the temperature and pressure VLE data suggested vapor interface growth from the heated surface to 5microm above the heated copper plate. Reinforcing the simulation results, including location and movement of phase interfaces, was accomplished through a thorough ten dimensionless number analyses. These specialized ratios indicated dominant fluid and heat transfer behavior including phase change conditions. Thus, fabrication and empirical results for the heat energy harvesting prototype were successful and computational modeling provided understanding of applicable internal system behavior.

Second Generation Prototype Design and Testing for a High Altitude Venus Balloon

NASA Technical Reports Server (NTRS)

Hall, J. L.; Kerzhanovich, V. V.; Yavrouian, A. H.; Plett, G. A.; Said, M.; Fairbrother, D.; Sandy, C.; Frederickson, T.; Sharpe, G.; Day, S.

2008-01-01

This paper describes the development of a second generation prototype balloon intended for flight in the upper atmosphere of Venus. The design of this new prototype incorporates lessons learned from the construction and testing of the first generation prototype, including finite element analyses of the balloon stresses and deformations, measured leak performance after handling and packaging, permeability and optical property measurements on material samples, and sulfuric acid testing. An improved design for the second generation prototype was formulated based on these results, although the spherical shape and 5.5 m diameter size were retained. The resulting balloon has a volume of 87 cubic meters and is capable of carrying a 45 kg payload at a 55 km altitude at Venus. The design and fabrication of the new prototype is described, along with test data for inflation and leakage performance.

Development of a prototype fluid volume measurement system. [for urine volume measurement on space missions

NASA Technical Reports Server (NTRS)

Poppendiek, H. F.; Sabin, C. M.; Meckel, P. T.

1974-01-01

The research is reported in applying the axial fluid temperature differential flowmeter to a urine volume measurement system for space missions. The fluid volume measurement system is described along with the prototype equipment package. Flowmeter calibration, electronic signal processing, and typical void volume measurements are also described.

Closely Coupled Multi-Mode Radiators: A New Concept for Improving the Perfomance of Electrically Small Antennas

DTIC Science & Technology

2015-11-23

realized gain values of−5.0 dBiC and 3.1 dBiC, respectively. Details of the design, optimization, simulation, and the measured results of the fabricated...prototype of this Fig. 4. The measured input VSWR of the antenna prototype shown in Fig. 3. 7    antenna were published in IEEE Transactions on...suppressed. Other prototypes of these types of MEFSSs were also designed and fabricated and characterized. Details of the design and measurement

Development of Composite Spectrophotometric Procedures for the Analysis of Low-Alloy Steels and of Aluminum and Its Alloys

DTIC Science & Technology

1952-11-01

COPPER lb Although copper can be determined by measurement of the blue cupric ammonia complex, the reaction is not very sensitive and is subject to...alkaline solution of the sample con- taining tartrate , provided a means of separation of copper by extraction of WADO TR 52-246 1 the copper bensoinoximate...potassium tartrate ), and sodium hydroxide solution added to ad- just the pH within the range ll3 to 12-3. After adding alpha-benzoinoxime the mixture was

Thermal conductance measurements of bolted copper joints for SuperCDMS

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

Schmitt, R.; Tatkowski, Greg; Ruschman, M.

2015-09-01

Joint thermal conductance testing has been undertaken for bolted copper to copper connections from 60 mK to 26 K. This testing was performed to validate an initial design basis for the SuperCDMS experiment, where a dilution refrigerator will be coupled to a cryostat via multiple bolted connections. Copper used during testing was either gold plated or passivated with citric acid to prevent surface oxidation. Results obtained are well fit by a power law regression of joint thermal conductance to temperature and match well with data collected during a literature review.

Line x-ray source for diffraction enhanced imaging in clinical and industrial applications

NASA Astrophysics Data System (ADS)

Wang, Xiaoqin

Mammography is one type of imaging modalities that uses a low-dose x-ray or other radiation sources for examination of breasts. It plays a central role in early detection of breast cancers. The material similarity of tumor-cell and health cell, breast implants surgery and other factors, make the breast cancers hard to visualize and detect. Diffraction enhanced imaging (DEI), first proposed and investigated by D. Chapman is a new x-ray radiographic imaging modality using monochromatic x-rays from a synchrotron source, which produced images of thick absorbing objects that are almost completely free of scatter. It shows dramatically improved contrast over standard imaging when applied to the same phantom. The contrast is based not only on attenuation but also on the refraction and diffraction properties of the sample. This imaging method may improve image quality of mammography, other medical applications, industrial radiography for non-destructive testing and x-ray computed tomography. However, the size, and cost, of a synchrotron source limits the application of the new modality to be applicable at clinical levels. This research investigates the feasibility of a designed line x-ray source to produce intensity compatible to synchrotron sources. It is composed of a 2-cm in length tungsten filament, installed on a carbon steel filament cup (backing plate), as the cathode and a stationary oxygen-free copper anode with molybdenum coating on the front surface serves as the target. Characteristic properties of the line x-ray source were computationally studied and the prototype was experimentally investigated. SIMIION code was used to computationally study the electron trajectories emanating from the filament towards the molybdenum target. A Faraday cup on the prototype device, proof-of-principle, was used to measure the distribution of electrons on the target, which compares favorably to computational results. The intensities of characteristic x-ray for molybdenum, tungsten and rhodium targets were investigated with different window materials for -30kV to -100kV applied potential. Heat loading and thermal management of the target has been investigated computationally using COMSOL code package, and experimental measurements of target temperature rise was taken via thermocouples attached to the target. Temperature measurements for low voltage, low current regime without active cooling were compared to computational results for code-experiment benchmarking. Two different phantoms were used in the simulation of DEI images, which showed that the designed x-ray source with DEI setup could produce images with significant improved contrast. The computational results, along with experimental measurements on the prototype setup, indicate the possibility of scale up to larger area x-ray source adequate for DEI applications.

Copper ions stimulate the proliferation of hepatic stellate cells via oxygen stress in vitro.

PubMed

Xu, San-qing; Zhu, Hui-yun; Lin, Jian-guo; Su, Tang-feng; Liu, Yan; Luo, Xiao-ping

2013-02-01

This study examined the effect of copper ions on the proliferation of hepatic stellate cells (HSCs) and the role of oxidative stress in this process in order to gain insight into the mechanism of hepatic fibrosis in Wilson's disease. LX-2 cells, a cell line of human HSCs, were cultured in vitro and treated with different agents including copper sulfate, N-acetyl cysteine (NAC) and buthionine sulfoximine (BSO) for different time. The proliferation of LX-2 cells was measured by non-radioactive cell proliferation assay. Real-time PCR and Western blotting were used to detect the mRNA and protein expression of platelet-derived growth factor receptor β subunit (PDGFβR), ELISA to determine the level of glutathione (GSH) and oxidized glutathione (GSSG), dichlorofluorescein assay to measure the level of reactive oxygen species (ROS), and lipid hydroperoxide assay to quantify the level of lipid peroxide (LPO). The results showed that copper sulfate over a certain concentration range could promote the proliferation of LX-2 cells in a time- and dose-dependent manner. The effect was most manifest when LX-2 cells were treated with copper sulfate at a concentration of 100 μmol/L for 24 h. Additionally, copper sulfate could dose-dependently increase the levels of ROS and LPO, and decrease the ratio of GSH/GSSG in LX-2 cells. The copper-induced increase in mRNA and protein expression of PDGFβR was significantly inhibited in LX-2 cells pre-treated with NAC, a precursor of GSH, and this phenomenon could be reversed by the intervention of BSO, an inhibitor of NAC. It was concluded that copper ions may directly stimulate the proliferation of HSCs via oxidative stress. Anti-oxidative stress therapies may help suppress the copper-induced activation and proliferation of HSCs.

Identifying Marine Copper-Binding Ligands in Seawater

NASA Astrophysics Data System (ADS)

Whitby, H.; Hollibaugh, J. T.; Maldonado, M. T.; Ouchi, S.; van den Berg, S. M.

2016-02-01

Complexation reactions are important because they affect the bioavailability of trace metals such as copper and iron. For example, organic complexation can determine whether copper is a limiting or a toxic micronutrient at natural levels. Copper competes with iron for complexing ligands, and when iron is limiting, copper can also substitute for iron in some metabolic pathways. The speciation of copper can be measured using complexing capacity titrations, which provide the concentration of individual ligand classes (L1, L2 etc.) and the complex stabilities (log K). Using methods recently developed in our laboratory, we show that the ligands within these classes can be measured independently of titrations, thus confirming the titration method and simultaneously identifying the ligands within each class. Thiols were identified as the L1 ligand class and humic compounds as the weaker L2 class in samples from coastal Georgia, USA, collected monthly from April to December. Log K values of the ligand complexes were consistent with values expected for thiols and humic substances. Recent results from culture studies and from samples collected along Line P, a coastal - oceanic transect in the HNLC region of the NE subarctic Pacific, will be presented in comparison to the estuarine results. This comparison will help to broaden our perspective on copper complexation and the ligands responsible, furthering our understanding of ligand sources and life cycles.

The preparation of copper fine particle paste and its application as the inner electrode material of a multilayered ceramic capacitor

NASA Astrophysics Data System (ADS)

Yonezawa, Tetsu; Takeoka, Shinsuke; Kishi, Hiroshi; Ida, Kiyonobu; Tomonari, Masanori

2008-04-01

Well size-controlled copper fine particles (diameter: 100-300 nm) were used as the inner electrode material of multilayered ceramic capacitors (MLCCs). The particles were dispersed in terpineol to form a printing paste with 50 wt% copper particles. The MLCC precursor modules prepared by the layer-by-layer printing of copper and BaTiO3 particles were cosintered. Detailed observation of the particles, paste, and MLCCs before and after sintering was carried out by electron microscopy. The sintering temperature of Cu-MLCC was as low as 960 °C. The permittivity of these MLCCs was successfully measured with the copper inner layers.

Prototype Systems for Measuring Outdoor Air Intake Rates in Rooftop Air Handlers

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

Fisk, William J.; Chan, Wanyu R.; Hotchi, Toshifumi

2015-01-01

The widespread absence of systems for real-time measurement and feedback control, of minimum outdoor air intake rates in HVAC systems contributes to the poor control of ventilation rates in commercial buildings. Ventilation rates affect building energy consumption and influence occupant health. The project designed fabricated and tested four prototypes of systems for measuring rates of outdoor air intake into roof top air handlers. All prototypes met the ±20% accuracy target at low wind speeds, with all prototypes accurate within approximately ±10% after application of calibration equations. One prototype met the accuracy target without a calibration. With two of four prototypemore » measurement systems, there was no evidence that wind speed or direction affected accuracy; however, winds speeds were generally below usually 3.5 m s -1 (12.6 km h -1) and further testing is desirable. The airflow resistance of the prototypes was generally less than 35 Pa at maximum RTU air flow rates. A pressure drop of this magnitude will increase fan energy consumption by approximately 4%. The project did not have resources necessary to estimate costs of mass produced systems. The retail cost of components and materials used to construct prototypes ranged from approximately $1,200 to $1,700. The test data indicate that the basic designs developed in this project, particularly the designs of two of the prototypes, have considerable merit. Further design refinement, testing, and cost analysis would be necessary to fully assess commercial potential. The designs and test results will be communicated to the HVAC manufacturing community.« less

Purity test for copper-plating solutions

NASA Technical Reports Server (NTRS)

Mansfeld, F. B.

1977-01-01

Electrode configuration can be used to measure extent of impurities in acid-copper plating solution. It can be inserted into any plating tank and will show whether bath is clean or contaminated, within fifteen minutes.

Electrochemical Behavior of Pure Copper in Phosphate Buffer Solutions: A Comparison Between Micro- and Nano-Grained Copper

NASA Astrophysics Data System (ADS)

Imantalab, O.; Fattah-alhosseini, A.; Keshavarz, M. K.; Mazaheri, Y.

2016-02-01

In this work, electrochemical behavior of annealed (micro-) and nano-grained pure copper (fabricated by accumulative roll bonding process) in phosphate buffer solutions of various pH values ranging from 10.69 to 12.59 has been studied. Before any electrochemical measurements, evaluation of microstructure was obtained by optical microscope and transmission electron microscopy. To investigate the electrochemical behavior of the samples, the potentiodynamic polarization, Mott-Schottky analysis, and electrochemical impedance spectroscopy (EIS) were carried out. Potentiodynamic polarization plots and EIS measurements revealed that as a result of grain refinement, the passive behavior of the nano-grained sample was improved compared to that of annealed pure copper. Also, Mott-Schottky analysis indicated that the passive films behaved as p-type semiconductors and grain refinement did not change the semiconductor type of passive films.

Radon daughter plate-out measurements at SNOLAB for polyethylene and copper

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

Stein, Matthew; Bauer, Dan; Bunker, Ray

We report that polyethylene and copper samples were exposed to the underground air at SNOLAB for approximately three months while several environmental factors were monitored. Predictions of the radon-daughter plate-out rate are compared to the resulting surface activities, obtained from high-sensitivity measurements of alpha emissivity using the XIA UltraLo-1800 spectrometer at Southern Methodist University. From these measurements, we determine an average 210Pb plate-out rate of 249 and 423 atoms/day/cm 2 for polyethylene and copper, respectively, when exposed to radon activity concentration of 135 Bq/m 3 at SNOLAB. Finally, a time-dependent model of alpha activity is discussed for these materials placedmore » in similar environmental conditions.« less

Radon daughter plate-out measurements at SNOLAB for polyethylene and copper

DOE PAGES

Stein, Matthew; Bauer, Dan; Bunker, Ray; ...

2017-11-04

We report that polyethylene and copper samples were exposed to the underground air at SNOLAB for approximately three months while several environmental factors were monitored. Predictions of the radon-daughter plate-out rate are compared to the resulting surface activities, obtained from high-sensitivity measurements of alpha emissivity using the XIA UltraLo-1800 spectrometer at Southern Methodist University. From these measurements, we determine an average 210Pb plate-out rate of 249 and 423 atoms/day/cm 2 for polyethylene and copper, respectively, when exposed to radon activity concentration of 135 Bq/m 3 at SNOLAB. Finally, a time-dependent model of alpha activity is discussed for these materials placedmore » in similar environmental conditions.« less

“In vitro” Implantation Technique Based on 3D Printed Prosthetic Prototypes

NASA Astrophysics Data System (ADS)

Tarnita, D.; Boborelu, C.; Geonea, I.; Malciu, R.; Grigorie, L.; Tarnita, D. N.

2018-06-01

In this paper, Rapid Prototyping ZCorp 310 system, based on high-performance composite powder and on resin-high strength infiltration system and three-dimensional printing as a manufacturing method are used to obtain physical prototypes of orthopaedic implants and prototypes of complex functional prosthetic systems directly from the 3D CAD data. These prototypes are useful for in vitro experimental tests and measurements to optimize and obtain final physical prototypes. Using a new elbow prosthesis model prototype obtained by 3D printing, the surgical technique of implantation is established. Surgical implantation was performed on male corpse elbow joint.

rf breakdown measurements in electron beam driven 200 GHz copper and copper-silver accelerating structures

DOE PAGES

Dal Forno, Massimo; Dolgashev, Valery; Bowden, Gordon; ...

2016-11-30

This study explores the physics of vacuum rf breakdowns in subterahertz high-gradient traveling-wave accelerating structures. We present the experimental results of rf tests of 200 GHz metallic accelerating structures, made of copper and copper-silver. These experiments were carried out at the Facility for Advanced Accelerator Experimental Tests (FACET) at the SLAC National Accelerator Laboratory. The rf fields were excited by the FACET ultrarelativistic electron beam. The traveling-wave structure is an open geometry, 10 cm long, composed of two halves separated by a gap. The rf frequency of the fundamental accelerating mode depends on the gap size and can be changedmore » from 160 to 235 GHz. When the beam travels off axis, a deflecting field is induced in addition to the longitudinal field. We measure the deflecting forces by observing the displacement of the electron bunch and use this measurement to verify the expected accelerating gradient. Furthermore, we present the first quantitative measurement of rf breakdown rates in 200 GHz metallic accelerating structures. The breakdown rate of the copper structure is 10 –2 per pulse, with a peak surface electric field of 500 MV/m and a rf pulse length of 0.3 ns, which at a relatively large gap of 1.5 mm, or one wavelength, corresponds to an accelerating gradient of 56 MV/m. For the same breakdown rate, the copper-silver structure has a peak electric field of 320 MV/m at a pulse length of 0.5 ns. For a gap of 1.1 mm, or 0.74 wavelengths, this corresponds to an accelerating gradient of 50 MV/m.« less

Evaluation of UV-fs-LA-MC-ICP-MS for precise in situ copper isotopic microanalysis of cubanite.

PubMed

Ikehata, Kei; Hirata, Takafumi

2013-01-01

We evaluated the capabilities of an in situ method for measuring copper isotopes of cubanite using UV-fs-LA-MC-ICP-MS. A comparison of the UV-fs laser results with those obtained from the NIR-fs laser system shows that there is obviously an improvement in the precision (<0.10‰, 2SE) when using the UV-fs laser. In both wavelength modes, matrix-matched standards are required for reliable in situ copper isotope analysis of cubanite. This method was applied to determinations for copper isotopes of minute cubanite grains in a skarn ore. Copper isotopic ratios of cubanite grains near a weathered surface of the sample are lower than those of intact cubanite grains within the sample, suggesting that selective leaching of heavier copper isotope in primary minerals occurred during weathering.

Affinity and Efficacy of Copper Following an Algicide Exposure: Application of the Critical Burden Concept for Lyngbya wollei Control in Lay Lake, AL

NASA Astrophysics Data System (ADS)

Bishop, West M.; Willis, Ben E.; Horton, C. Todd

2015-04-01

Accurate predictions of nuisance algae responses to algicide exposures are needed to guide management decisions. Copper sorption and responses of Lyngbya wollei (Farlow ex Gomont) Speziale and Dyck were measured in the laboratory and two areas in Lay Lake (AL, USA) to treatments of Captain® XTR (SePRO Corporation; chelated copper algicide) and a sequential treatment of GreenClean® Liquid (BioSafe Systems, LLC; peroxygen algicide) combined with Hydrothol® 191 (United Phosphorus, Inc.; endothall algicide) followed by Captain XTR. Measured filament viability in laboratory exposures predicted Captain XTR alone could control L. wollei in Lay Lake, with 2 mg Cu/g algae EC75. This produced a targeted field treatment of 9.7 kg Cu/ha which was divided into three applications of 0.3 mg Cu/L as Captain XTR in the treatment areas. Laboratory and field experiments indicated treatments of Captain XTR alone and the combination treatment resulted in comparable copper sorption and responses of L. wollei. Copper adsorbed greater to L. wollei in laboratory experiments than in the treated areas of Lay Lake with comparable exposures (2 mg Cu/g L. wollei). However, responses and infused copper were similar and correlated in laboratory experiments and treated areas of Lay Lake indicating infused copper is critical for governing toxicity. Laboratory exposures as mg Cu/g algae accurately predicted the necessary algicide exposure required to attain the critical burden of infused copper and elicit desired responses of L. wollei in treated areas of Lay Lake.

Electrochemical fabrication and optoelectronic properties of hybrid heterostructure of CuPc/porous GaN

NASA Astrophysics Data System (ADS)

Peng, Fei; Qin, Shuang-Jiao; Hu, Li-Feng; Wang, Juan-Ye; Yang, Jia-Mei; Chen, Xue-Qing; Pan, Ge-Bo

2016-05-01

A new hybrid heterostructure of p-type copper phthalocyanine (CuPc) and n-type porous GaN (PGaN) has been fabricated by electrophoretic deposition. The influence of CuPc concentration, electric field intensity, and deposition time on the growth of CuPc film has been explored. The as-prepared CuPc films are made of numerous nanorods. The X-ray diffraction (XRD) spectra revealed that the CuPc films are the β phase and amorphous type on pristine and porous GaN, respectively. Moreover, the prototype devices were fabricated on the basis of the CuPc/PGaN heterostructures. The devices exhibited excellent photodetector performance under ultraviolet (UV) light illumination.

20 kHz, 25 kVA node power transformer

NASA Technical Reports Server (NTRS)

Hussey, S.

1989-01-01

The electrical and mechanical design information and the electrical and thermal testing performed on the 440-208-V rms, 20-kHz, 25-kVa prototype node transformer are summarized. The calculated efficiency of the node transformer is 99.3 percent based on core loss and copper loss test data, and its maximum calculated load regulation is 0.7 percent. The node transformer has a weight of 19.7 lb and has a power density of 0.8 lb/kW. The hot-spot temperature rise is estimated to be 33 C above the cold plate mounting base. This proof-of-concept transformer design is a viable candidate for the space station Freedom application.

Integration of ZnO and CuO nanowires into a thermoelectric module

PubMed Central

Dalola, Simone; Faglia, Guido; Comini, Elisabetta; Ferroni, Matteo; Soldano, Caterina; Ferrari, Vittorio; Sberveglieri, Giorgio

2014-01-01

Summary Zinc oxide (ZnO, n-type) and copper oxide (CuO, p-type) nanowires have been synthesized and preliminarily investigated as innovative materials for the fabrication of a proof-of-concept thermoelectric device. The Seebeck coefficients, electrical conductivity and thermoelectric power factors (TPF) of both semiconductor materials have been determined independently using a custom experimental set-up, leading to results in agreement with available literature with potential improvement. Combining bundles of ZnO and CuO nanowires in a series of five thermocouples on alumina leads to a macroscopic prototype of a planar thermoelectric generator (TEG) unit. This demonstrates the possibility of further integration of metal oxide nanostructures into efficient thermoelectric devices. PMID:24991531

Integration of ZnO and CuO nanowires into a thermoelectric module.

PubMed

Zappa, Dario; Dalola, Simone; Faglia, Guido; Comini, Elisabetta; Ferroni, Matteo; Soldano, Caterina; Ferrari, Vittorio; Sberveglieri, Giorgio

2014-01-01

Zinc oxide (ZnO, n-type) and copper oxide (CuO, p-type) nanowires have been synthesized and preliminarily investigated as innovative materials for the fabrication of a proof-of-concept thermoelectric device. The Seebeck coefficients, electrical conductivity and thermoelectric power factors (TPF) of both semiconductor materials have been determined independently using a custom experimental set-up, leading to results in agreement with available literature with potential improvement. Combining bundles of ZnO and CuO nanowires in a series of five thermocouples on alumina leads to a macroscopic prototype of a planar thermoelectric generator (TEG) unit. This demonstrates the possibility of further integration of metal oxide nanostructures into efficient thermoelectric devices.

Responses of Lyngbya wollei to exposures of copper-based algaecides: the critical burden concept.

PubMed

Bishop, W M; Rodgers, J H

2012-04-01

The formulation of a specific algaecide can greatly influence the bioavailability, uptake, and consequent control of the targeted alga. In this research, three copper-based algaecide formulations were evaluated in terms of copper sorption to a specific problematic alga and amount of copper required to achieve control. The objectives of this study were (1) to compare the masses of copper required to achieve control of Lyngbya wollei using the algaecide formulations Algimycin-PWF, Clearigate, and copper sulfate pentahydrate in laboratory toxicity experiments; (2) to relate the responses of L. wollei to the masses of copper adsorbed and absorbed (i.e., dose) as well as the concentrations of copper in the exposure water; and (3) to discern the relation between the mass of copper required to achieve control of a certain mass of L. wollei among different algaecide formulations. The critical burden of copper (i.e., threshold algaecide concentration that must be absorbed or adsorbed to achieve control) for L. wollei averaged 3.3 and 1.9 mg Cu/g algae for Algimycin-PWF and Clearigate, respectively, in experiments with a series of aqueous copper concentrations, water volumes, and masses of algae. With reasonable exposures in these experiments, control was not achieved with single applications of copper sulfate despite copper sorption >13 mg Cu/g algae in one experiment. Factors governing the critical burden of copper required for control of problematic cyanobacteria include algaecide formulation and concentration, volume of water, and mass of algae. By measuring the critical burden of copper from an algaecide formulation necessary to achieve control of the targeted algae, selection of an effective product and treatment rate can be calculated at a given field site.

Optical performance of prototype horn-coupled TES bolometer arrays for SAFARI

NASA Astrophysics Data System (ADS)

Audley, Michael D.; de Lange, Gert; Gao, Jian-Rong; Khosropanah, Pourya; Hijmering, Richard; Ridder, Marcel L.

2016-07-01

The SAFARI Detector Test Facility is an ultra-low background optical testbed for characterizing ultra-sensitive prototype horn-coupled TES bolmeters for SAFARI, the grating spectrometer on board the proposed SPICA satellite. The testbed contains internal cold and hot black-body illuminators and a light-pipe for illumination with an external source. We have added reimaging optics to facilitate array optical measurements. The system is now being used for optical testing of prototype detector arrays read out with frequency-domain multiplexing. We present our latest optical measurements of prototype arrays and discuss these in terms of the instrument performance.

Role of Copper and Homocysteine in Pressure Overload Heart Failure

PubMed Central

Hughes, William M.; Rodriguez, Walter E.; Rosenberger, Dorothea; Chen, Jing; Sen, Utpal; Tyagi, Neetu; Moshal, Karni S.; Vacek, Thomas; Kang, Y. James

2009-01-01

Elevated levels of homocysteine (Hcy) (known as hyperhomocysteinemia HHcy) are involved in dilated cardiomyopathy. Hcy chelates copper and impairs copper-dependent enzymes. Copper deficiency has been linked to cardiovascular disease. We tested the hypothesis that copper supplement regresses left ventricular hypertrophy (LVH), fibrosis and endothelial dysfunction in pressure overload DCM mice hearts. The mice were grouped as sham, sham + Cu, aortic constriction (AC), and AC + Cu. Aortic constriction was performed by transverse aortic constriction. The mice were treated with or without 20 mg/kg copper supplement in the diet for 12 weeks. The cardiac function was assessed by echocardiography and electrocardiography. The matrix remodeling was assessed by measuring matrix metalloproteinase (MMP), tissue inhibitor of metalloproteinases (TIMPs), and lysyl oxidase (LOX) by Western blot analyses. The results suggest that in AC mice, cardiac function was improved with copper supplement. TIMP-1 levels decreased in AC and were normalized in AC + Cu. Although MMP-9, TIMP-3, and LOX activity increased in AC and returned to baseline value in AC + Cu, copper supplement showed no significant effect on TIMP-4 activity after pressure overload. In conclusion, our data suggest that copper supplement helps improve cardiac function in a pressure overload dilated cardiomyopathic heart. PMID:18679830

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.

Production of brown and black pigments by using flotation waste from copper slag.

PubMed

Ozel, Emel; Turan, Servet; Coruh, Semra; Ergun, Osman Nuri

2006-04-01

One of the major problems in copper-producing countries is the treatment of the large amount of copper slag or copper flotation waste generated from copper slag which contains significant amounts of heavy metals such as Cu, Zn, Pb and Co. Dumping or disposal of such large quantities of flotation waste from copper slag causes environmental and space problems. In this study, the treatment of flotation waste from copper slag by a thermal method and its use as an iron source in the production of inorganic brown and black pigments that are used in the ceramic industry were investigated. The pigments were produced by calcining different amounts of flotation waste and chromite, Cr2O3, ZnO and CoO mixtures. The pigments obtained were added to transparent ceramic glazes and porcelainized tile bodies. Their colours were defined by L*a*b* measurements with a spectrophotometer. The results showed that flotation waste from copper slag could be used as an iron source to produce brown and black pigments in both ceramic body and glazes.

Advanced ultrasonic measurement methodology for non-invasive interrogation and identification of fluids in sealed containers

NASA Astrophysics Data System (ADS)

Tucker, Brian J.; Diaz, Aaron A.; Eckenrode, Brian A.

2006-03-01

Government agencies and homeland security related organizations have identified the need to develop and establish a wide range of unprecedented capabilities for providing scientific and technical forensic services to investigations involving hazardous chemical, biological, and radiological materials, including extremely dangerous chemical and biological warfare agents. Pacific Northwest National Laboratory (PNNL) has developed a prototype portable, hand-held, hazardous materials acoustic inspection prototype that provides noninvasive container interrogation and material identification capabilities using nondestructive ultrasonic velocity and attenuation measurements. Due to the wide variety of fluids as well as container sizes and materials encountered in various law enforcement inspection activities, the need for high measurement sensitivity and advanced ultrasonic measurement techniques were identified. The prototype was developed using a versatile electronics platform, advanced ultrasonic wave propagation methods, and advanced signal processing techniques. This paper primarily focuses on the ultrasonic measurement methods and signal processing techniques incorporated into the prototype. High bandwidth ultrasonic transducers combined with an advanced pulse compression technique allowed researchers to 1) obtain high signal-to-noise ratios and 2) obtain accurate and consistent time-of-flight (TOF) measurements through a variety of highly attenuative containers and fluid media. Results of work conducted in the laboratory have demonstrated that the prototype experimental measurement technique also provided information regarding container properties, which will be utilized in future container-independent measurements of hidden liquids.

A novel EPID design for enhanced contrast and detective quantum efficiency

NASA Astrophysics Data System (ADS)

Rottmann, Joerg; Morf, Daniel; Fueglistaller, Rony; Zentai, George; Star-Lack, Josh; Berbeco, Ross

2016-09-01

Beams-eye-view imaging applications such as real-time soft-tissue motion estimation are hindered by the inherently low image contrast of electronic portal imaging devices (EPID) currently available for clinical use. We introduce and characterize a novel EPID design that provides substantially increased detective quantum efficiency (DQE), contrast-to-noise ratio (CNR) and sensitivity without degradation in spatial resolution. The prototype design features a stack of four conventional EPID layers combined with low noise integrated readout electronics. Each layer consists of a copper plate, a scintillator (\\text{G}{{\\text{d}}2}{{\\text{O}}2}{{\\text{S}}{}}\\text{:Tb} ) and a photodiode/TFT-switch (aSi:H). We characterize the prototype’s signal response to a 6 MV photon beam in terms of modulation transfer function (MTF), DQE and CNR. The presampled MTF is estimated using a slanted slit technique, the DQE is calculated from measured normalized noise power spectra (nNPS) and the MTF and CNR is estimated using a Las Vegas contrast phantom. The prototype has been designed and built to be interchangeable with the current clinical EPID on the Varian TrueBeam platform (AS-1200) in terms of size and data output specifications. Performance evaluation is conducted in absolute values as well as in relative terms using the Varian AS-1200 EPID as a reference detector. A fivefold increase of DQE(0) to about 6.7% was observed by using the four-layered design versus the AS-1200 reference detector. No substantial differences are observed between each layer’s individual MTF and the one for all four layers operating combined indicating that defocusing due to beam divergence is negligible. Also, using four layers instead of one increases the signal to noise ratio by a factor of 1.7.

An electronic nose for reliable measurement and correct classification of beverages.

PubMed

Mamat, Mazlina; Samad, Salina Abdul; Hannan, Mahammad A

2011-01-01

This paper reports the design of an electronic nose (E-nose) prototype for reliable measurement and correct classification of beverages. The prototype was developed and fabricated in the laboratory using commercially available metal oxide gas sensors and a temperature sensor. The repeatability, reproducibility and discriminative ability of the developed E-nose prototype were tested on odors emanating from different beverages such as blackcurrant juice, mango juice and orange juice, respectively. Repeated measurements of three beverages showed very high correlation (r > 0.97) between the same beverages to verify the repeatability. The prototype also produced highly correlated patterns (r > 0.97) in the measurement of beverages using different sensor batches to verify its reproducibility. The E-nose prototype also possessed good discriminative ability whereby it was able to produce different patterns for different beverages, different milk heat treatments (ultra high temperature, pasteurization) and fresh and spoiled milks. The discriminative ability of the E-nose was evaluated using Principal Component Analysis and a Multi Layer Perception Neural Network, with both methods showing good classification results.

An Electronic Nose for Reliable Measurement and Correct Classification of Beverages

PubMed Central

Mamat, Mazlina; Samad, Salina Abdul; Hannan, Mahammad A.

2011-01-01

This paper reports the design of an electronic nose (E-nose) prototype for reliable measurement and correct classification of beverages. The prototype was developed and fabricated in the laboratory using commercially available metal oxide gas sensors and a temperature sensor. The repeatability, reproducibility and discriminative ability of the developed E-nose prototype were tested on odors emanating from different beverages such as blackcurrant juice, mango juice and orange juice, respectively. Repeated measurements of three beverages showed very high correlation (r > 0.97) between the same beverages to verify the repeatability. The prototype also produced highly correlated patterns (r > 0.97) in the measurement of beverages using different sensor batches to verify its reproducibility. The E-nose prototype also possessed good discriminative ability whereby it was able to produce different patterns for different beverages, different milk heat treatments (ultra high temperature, pasteurization) and fresh and spoiled milks. The discriminative ability of the E-nose was evaluated using Principal Component Analysis and a Multi Layer Perception Neural Network, with both methods showing good classification results. PMID:22163964

Highly selective plasma-activated copper catalysts for carbon dioxide reduction to ethylene

DOE PAGES

Mistry, Hemma; Varela, Ana Sofia; Bonifacio, Cecile S.; ...

2016-06-30

There is an urgent need to develop technologies that use renewable energy to convert waste products such as carbon dioxide into hydrocarbon fuels. Carbon dioxide can be electrochemically reduced to hydrocarbons over copper catalysts, although higher efficiency is required. We have developed oxidized copper catalysts displaying lower overpotentials for carbon dioxide electroreduction and record selectivity towards ethylene (60%) through facile and tunable plasma treatments. Herein we provide insight into the improved performance of these catalysts by combining electrochemical measurements with microscopic and spectroscopic characterization techniques. Operando X-ray absorption spectroscopy and cross-sectional scanning transmission electron microscopy show that copper oxides aremore » surprisingly resistant to reduction and copper + species remain on the surface during the reaction. Furthermore, our results demonstrate that the roughness of oxide-derived copper catalysts plays only a partial role in determining the catalytic performance, while the presence of copper + is key for lowering the onset potential and enhancing ethylene selectivity.« less

EPDM Based Double Slope Triangular Enclosure Solar Collector: A Novel Approach

PubMed Central

Qureshi, Shafiq R.; Khan, Waqar A.

2014-01-01

Solar heating is one of the important utilities of solar energy both in domestic and industrial sectors. Evacuated tube heaters are a commonly used technology for domestic water heating. However, increasing cost of copper and nickel has resulted in huge initial cost for these types of heaters. Utilizing solar energy more economically for domestic use requires new concept which has low initial and operating costs together with ease of maintainability. As domestic heating requires only nominal heating temperature to the range of 60–90°C, therefore replacing nickel coated copper pipes with any cheap alternate can drastically reduce the cost of solar heater. We have proposed a new concept which utilizes double slope triangular chamber with EPDM based synthetic rubber pipes. This has reduced the initial and operating costs substantially. A detailed analytical study was carried out to design a novel solar heater. On the basis of analytical design, a prototype was manufactured. Results obtained from the experiments were found to be in good agreement with the analytical study. A maximum error of 10% was recorded at noon. However, results show that error is less than 5% in early and late hours. PMID:24688407

EPDM based double slope triangular enclosure solar collector: a novel approach.

PubMed

Qureshi, Shafiq R; Khan, Waqar A; Sarwar, Waqas

2014-01-01

Solar heating is one of the important utilities of solar energy both in domestic and industrial sectors. Evacuated tube heaters are a commonly used technology for domestic water heating. However, increasing cost of copper and nickel has resulted in huge initial cost for these types of heaters. Utilizing solar energy more economically for domestic use requires new concept which has low initial and operating costs together with ease of maintainability. As domestic heating requires only nominal heating temperature to the range of 60-90 °C, therefore replacing nickel coated copper pipes with any cheap alternate can drastically reduce the cost of solar heater. We have proposed a new concept which utilizes double slope triangular chamber with EPDM based synthetic rubber pipes. This has reduced the initial and operating costs substantially. A detailed analytical study was carried out to design a novel solar heater. On the basis of analytical design, a prototype was manufactured. Results obtained from the experiments were found to be in good agreement with the analytical study. A maximum error of 10% was recorded at noon. However, results show that error is less than 5% in early and late hours.

Study and development of CW room temperature rebuncher for SARAF accelerator

NASA Astrophysics Data System (ADS)

Kaizer, B.; Rodnizki, J.; Farber, E.; Perry, A.; Danon, L.; Horvitz, Z.; Mazor, O.; Friedman, A.; Di Giacomo, M.; Leyge, J.-F.; Michel, M.; Toussaint, P.

2017-11-01

The SARAF 176 MHz accelerator is designed to provide CW proton/deuteron beams up to 5 mA current and 40 MeV accelerated ion energy. Phase I of SARAF (up to 4-5 MeV) has been installed, commissioned, and is available for experimental work. Phase II of SARAF is currently in the design and first prototyping stage and will contain longer MEBT with three rebunchers and four cryomodules, each consisting of SC HWRs and solenoids. Phase II MEBT line is designed to follow a 1.3 MeV/u RFQ, is 4.5 m long, and contains three 176 MHz rebunchers providing a field integral of 105 kV. Different rebuncher configurations have been studied in order to minimize the RF losses and maximize the shunt impedance. Different apertures have also been tested with the 40 mm diameter required by beam dynamics. The simulations were done using CST Microwave Studio. CEA leads the design for SARAF phase II linac including the MEBT rebunchers and has studied a mixed solid copper and Cu plated stainless steel, 3-gap cavity. SNRC is developing a 4-gap OFHC copper rebuncher as a risk reduction. Both designs are presented and discussed in the paper.

Definition study for an advanced cosmic ray experiment utilizing the long duration exposure facility

NASA Astrophysics Data System (ADS)

Price, P. B.

1982-06-01

To achieve the goals of cosmic ray astrophysics, an ultraheavy cosmic ray experiment on an LDEF reflight should be in an orbit with high inclination (approximately 57 deg) at approximately 230 nm for approximately 2 years near solar minimum (approximately 1986). It should fill 61 trays. Each tray should contain 4 modules of total active area 0.7 sq m, with a thermal blanket, thermal labyrinth mounts, aluminum honeycomb mechanical support, and total weight approximately 100 kg. Each module should contain interleaved CR39, Lexan, and thin copper sheets plus one event-thermometer canned in a thin metal cannister sealed with approximately 0.2 atm dry O2. The CR39 and Lexan should be manufactured to specifications and the sheet copper rolled to specifications. The event-thermometer should be a stiffened CR39 sheet that slides via bimetal strips relative to fixed CR39 sheet so that stack temperature can be read out for each event. The metal cannister can be collapsed at launch and landing, capturing the sliding assembly to prevent damage. An engineering study should be made of a prototype LDEF tray; this will include thermal and mechanical tests of detectors and the event thermometer.

Definition study for an advanced cosmic ray experiment utilizing the long duration exposure facility

NASA Technical Reports Server (NTRS)

Price, P. B.

1982-01-01

To achieve the goals of cosmic ray astrophysics, an ultraheavy cosmic ray experiment on an LDEF reflight should be in an orbit with high inclination (approximately 57 deg) at approximately 230 nm for approximately 2 years near solar minimum (approximately 1986). It should fill 61 trays. Each tray should contain 4 modules of total active area 0.7 sq m, with a thermal blanket, thermal labyrinth mounts, aluminum honeycomb mechanical support, and total weight approximately 100 kg. Each module should contain interleaved CR39, Lexan, and thin copper sheets plus one event-thermometer canned in a thin metal cannister sealed with approximately 0.2 atm dry O2. The CR39 and Lexan should be manufactured to specifications and the sheet copper rolled to specifications. The event-thermometer should be a stiffened CR39 sheet that slides via bimetal strips relative to fixed CR39 sheet so that stack temperature can be read out for each event. The metal cannister can be collapsed at launch and landing, capturing the sliding assembly to prevent damage. An engineering study should be made of a prototype LDEF tray; this will include thermal and mechanical tests of detectors and the event thermometer.

EXPERIMENTAL INVESTIGATION OF PIC FORMATION ...

EPA Pesticide Factsheets

The report gives results of experiments to assess: (1) the effect of residual copper retained in an incineration facility on polychlorinated dibenzo-p-dioxin and dibenzofuran (PCDD/PCDF) formation during incineration of non-copper-containing chlorofluorocarbons (CFCs); and (2) the formation of chlorinated and aromatic products of incomplete combustion (PICs), including PCDD/PCDFs, during incineration of CFC recycling residue and hydrochlorofluorocarbons (HCFCs). High concentrations of PCDD/PCDFs (23,800 ng/dscm at 7% O2) measured in FY91 during incineration of CFC-12 in a turbulent flame reactor (TFR) could not be repeated in the present study. Repetition tests conducted in the same facility under similar operating conditions resulted in PCDD/PCDF concentrations of 118ng/dscm at 7% O2. However, results of the present study suggest that residual copper retained in an incineration facility possibly promotes the formation of PCDD/PCDFs during incineration of CFC-12 which does not contain copper. Tests conducted in the TFR resulted in measured PCDD/PCDF concentrations of 386-454 ng/dscm at 7% O2 during incineration of CFC-12 which followed incineration of copper-containing compounds. These results suggest that CFCs may best be incinerated in incinerators which do not treat any copper-containing waste prior to CFC incineration. Report available at NTIS as PB96152186. To share information

Decreased endometrial HOXA10 expression associated with use of the copper intrauterine-device

PubMed Central

Tetrault, Amy M; Richman, Susan M; Fei, Xiaolan; Taylor, Hugh S

2009-01-01

Objective To characterize human endometrial HOXA10 expression in patients using copper intrauterine devices (IUD). Design Case-control study. Setting Academic medical center Patient(s) Women using copper IUD Interventions(s) Immunohistochemical analysis of endometrial HOXA10 expression in biopsies obtained from 24 women using copper Paraguard T380A as well as in biopsies obtained from 10 normal cycling women who were not using IUD or hormonal contraceptives. Main Outcome Measure(s) Endometrial HOXA10 expression. Result(s) Endometrial HOXA10 expression was markedly decreased in biopsies obtained from women using IUD contraceptive when compared to controls. The mean H score for endometrial stromal cell HOXA10 expression in biopsies obtained from women using Paraguard IUD was 0.21 compared to 2.2 in the control endometrial biopsies (P<0.001). Endometrial glandular expression of HOXA10 was absent in all IUD users. Conclusion(s) Decreased endometrial HOXA10 expression was apparent in women who use a copper IUD. Expression of HOXA10 is essential for endometrial receptivity. A novel mechanism of copper IUD action involves suppression of genes required for endometrial receptivity. The dramatic decrease of endometrial HOXA10 in response to IUD use may contribute to contraceptive efficacy. PMID:18930214

Reduced recruitment in Hyalella azteca (Saussure, 1858) exposed to copper.

PubMed

Othman, M Shuhaimi; Pascoe, David

2002-09-01

Neonates of the amphipod Hyalella azteca were exposed for a 35-day period in the laboratory to a range of copper concentrations, nominally 18 microg/l, 40 microg/l, 70 microg/l and 260 microg/l. The reproductive status of the population was assessed by recording recruitment, the number of precopulatory pairs and number of gravid females. At the end of the experiment, the body lengths of individuals were measured using image analysis. There was a significant decrease in the final population size of H. azteca with increasing copper concentration and compared with the control. Copper significantly reduced recruitment of juveniles and length composition of the final population and there was also a trend toward reduced precopula number with increasing copper concentrations.

The structure of molten CuCl: Reverse Monte Carlo modeling with high-energy X-ray diffraction data and molecular dynamics of a polarizable ion model

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

Alcaraz, Olga; Trullàs, Joaquim, E-mail: quim.trullas@upc.edu; Tahara, Shuta

2016-09-07

The results of the structural properties of molten copper chloride are reported from high-energy X-ray diffraction measurements, reverse Monte Carlo modeling method, and molecular dynamics simulations using a polarizable ion model. The simulated X-ray structure factor reproduces all trends observed experimentally, in particular the shoulder at around 1 Å{sup −1} related to intermediate range ordering, as well as the partial copper-copper correlations from the reverse Monte Carlo modeling, which cannot be reproduced by using a simple rigid ion model. It is shown that the shoulder comes from intermediate range copper-copper correlations caused by the polarized chlorides.

Adhesion, friction, and wear of a copper bicrystal with (111) and (210) grains

NASA Technical Reports Server (NTRS)

Brainard, W. A.; Buckley, D. H.

1973-01-01

Sliding friction experiments were conducted in air with polycrystalline copper and ruby riders sliding against a copper bicrystal. Friction coefficient was measured across the bicrystal surface, and the initiation of adhesive wear was examined with scanning electron microscopy. Results indicate a marked increase in friction coefficient as the copper rider crossed the grain boundary from the (111) plane to the (210) plane of the bicrystal. Adhesion, friction, and initiation of adhesive wear was notably different in the adjacent grains of differing orientation. A slip-band adhesion-generated fracture mechanism for wear particle formation is proposed.

Thermal conductance measurements of bolted copper joints for SuperCDMS

DOE PAGES

Schmitt, R. L.; Tatkowski, G.; Ruschman, M.; ...

2015-04-28

Joint thermal conductance testing has been undertaken for bolted copper to copper connections from 60 mK to 26 K. This testing was performed to validate an initial design basis for the SuperCDMS experiment, where a dilution refrigerator will be coupled to a cryostat via multiple bolted connections. Copper used during testing was either gold plated or passivated with citric acid to prevent surface oxidation. Finally, the results we obtained are well fit by a power law regression of joint thermal conductance to temperature and match well with data collected during a literature review.

Thermal conductance characterization of a pressed copper rope strap between 0.13 K and 10 K

DOE PAGES

Dhuley, R. C.; Ruschman, M.; Link, J. T.; ...

2017-07-05

Mechanically pressing the ends of a copper braid in solid copper is an effective way of constructing solderless conductive straps for cryogenic applications. In this paper we present thermal conductance data of such a copper strap measured using the two-heater one-thermometer method. The measurements span a wide temperature range of 0.13–10 K applicable to a variety of cryogenic systems employing liquid helium, pulse tube coolers, adiabatic demagnetization refrigerators, and others. Above ≈1.5 K, the braid thermal conductivity dominates the strap conductance resulting in a near-linear dependence with temperature. The variation with temperature below ≈1.5 K is near-quadratic indicating dominance ofmore » the pressed contact conductance at the strap ends. In conclusion, electron-beam welding the braid to the strap ends is shown to be a promising solution for improving sub-Kelvin thermal conductance of the strap.« less

Thermal conductance characterization of a pressed copper rope strap between 0.13 K and 10 K

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

Dhuley, R. C.; Ruschman, M.; Link, J. T.

Mechanically pressing the ends of a copper braid in solid copper is an effective way of constructing solderless conductive straps for cryogenic applications. In this paper we present thermal conductance data of such a copper strap measured using the two-heater one-thermometer method. The measurements span a wide temperature range of 0.13–10 K applicable to a variety of cryogenic systems employing liquid helium, pulse tube coolers, adiabatic demagnetization refrigerators, and others. Above ≈1.5 K, the braid thermal conductivity dominates the strap conductance resulting in a near-linear dependence with temperature. The variation with temperature below ≈1.5 K is near-quadratic indicating dominance ofmore » the pressed contact conductance at the strap ends. In conclusion, electron-beam welding the braid to the strap ends is shown to be a promising solution for improving sub-Kelvin thermal conductance of the strap.« less

Comparative contraceptive effectiveness of levonorgestrel-releasing and copper intrauterine devices: the European Active Surveillance Study for Intrauterine Devices.

PubMed

Heinemann, Klaas; Reed, Suzanne; Moehner, Sabine; Minh, Thai Do

2015-04-01

The objective was to measure the rate of unintended pregnancies in women using levonorgestrel-releasing intrauterine systems (LNG IUSs, releasing 20 mcg LNG daily) and copper intrauterine devices (IUDs) in a typical population of IUD users and to describe associated complications. A multinational, prospective, non-interventional cohort study of new users of LNG IUS and copper IUDs was performed. Following a baseline survey, study participants and their physicians completed one follow-up questionnaire after 12 months. A multifaceted four-level follow-up procedure minimized loss to follow-up. Patient-reported outcomes were validated by the treating physicians. A total of 61,448 women with a newly inserted IUD were enrolled in six European countries between 2006 and 2012. The copper IUD cohort contained more than 30 different types. Validated 1-year follow-up information for 58,324 users between 18 and 50 years of age (70% using LNG IUS, 30% using copper IUDs) was collected. A total of 118 contraceptive failures occurred (26 LNG, 92 copper). Both types of IUD were highly effective, with overall Pearl indices of 0.06 [95% confidence interval (CI): 0.04-0.09] and 0.52 (95% CI: 0.42-0.64) for LNG IUS and copper IUDs, respectively. The adjusted hazard ratio for LNG IUS vs. copper IUDs was 0.16 (95% CI: 0.10-0.25). Tenty-one pregnancies (7 LNG IUS, 14 copper IUD) were ectopic, yielding an adjusted hazard ratio for ectopic pregnancy of 0.26 (95% CI: 0.10-0.66). The contraceptive failure rate was low with both IUDs. However, the LNG IUS was associated with a significantly lower risk of pregnancy, including ectopic pregnancy, than the copper IUDs. To our knowledge, this is the first large-scale, multinational, prospective epidemiological study to measure and compare the contraceptive effectiveness of LNG IUSs and copper IUDs during routine clinical practice. Clinicians and patients should be aware of differences in rates of unintended pregnancies and associated complications in relation to IUD us. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

Quantifying the strength of the associations of prototype perceptions with behaviour, behavioural willingness and intentions: a meta-analysis.

PubMed

van Lettow, Britt; de Vries, Hein; Burdorf, Alex; van Empelen, Pepijn

2016-01-01

Prototypes (i.e., social images representing perceptions of typical persons engaging in or refraining from certain behaviour) have been shown to explain health-related behaviours. The present meta-analysis quantified the strength of the associations of prototype perceptions with health motivation and behaviour. Specifically, the analysis addressed (i) the relationship of prototype favourability (i.e., degree of likability) and similarity (i.e., perceived resemblance to the self) with behaviour, willingness and intentions; (ii) the effect of the interaction between favourability and similarity; and (iii) the extent to which health-risk and health-protective prototypes differed in their association with these outcomes. A total of 80 independent studies were identified based on 69 articles. The results indicated that prototype favourability and similarity were related to behaviour, intentions and willingness with small-to-medium effect sizes (r+ = 0.12-0.43). Direct measures of prototype perceptions generally produced larger effects than indirect measures. The interaction between favourability and similarity produced small-to-large effect sizes (r+ = .22-.54). The results suggest that both health-risk and health-protective prototypes might be useful targets for interventions (r+ = .22-.54). In order to increase health-protective behaviours, intentions and behaviour could be targeted by increasing similarity to health-protective prototypes. Health-risk behaviour might be decreased by targeting willingness by modifying health-risk prototype favourability and similarity.

Evidence for widespread, severe brain copper deficiency in Alzheimer's dementia.

PubMed

Xu, Jingshu; Church, Stephanie J; Patassini, Stefano; Begley, Paul; Waldvogel, Henry J; Curtis, Maurice A; Faull, Richard L M; Unwin, Richard D; Cooper, Garth J S

2017-08-16

Datasets comprising simultaneous measurements of many essential metals in Alzheimer's disease (AD) brain are sparse, and available studies are not entirely in agreement. To further elucidate this matter, we employed inductively-coupled-plasma mass spectrometry to measure post-mortem levels of 8 essential metals and selenium, in 7 brain regions from 9 cases with AD (neuropathological severity Braak IV-VI), and 13 controls who had normal ante-mortem mental function and no evidence of brain disease. Of the regions studied, three undergo severe neuronal damage in AD (hippocampus, entorhinal cortex and middle-temporal gyrus); three are less-severely affected (sensory cortex, motor cortex and cingulate gyrus); and one (cerebellum) is relatively spared. Metal concentrations in the controls differed among brain regions, and AD-associated perturbations in most metals occurred in only a few: regions more severely affected by neurodegeneration generally showed alterations in more metals, and cerebellum displayed a distinctive pattern. By contrast, copper levels were substantively decreased in all AD-brain regions, to 52.8-70.2% of corresponding control values, consistent with pan-cerebral copper deficiency. This copper deficiency could be pathogenic in AD, since levels are lowered to values approximating those in Menkes' disease, an X-linked recessive disorder where brain-copper deficiency is the accepted cause of severe brain damage. Our study reinforces others reporting deficient brain copper in AD, and indicates that interventions aimed at safely and effectively elevating brain copper could provide a new experimental-therapeutic approach.

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

Mistry, Hemma; Varela, Ana Sofia; Bonifacio, Cecile S.

There is an urgent need to develop technologies that use renewable energy to convert waste products such as carbon dioxide into hydrocarbon fuels. Carbon dioxide can be electrochemically reduced to hydrocarbons over copper catalysts, although higher efficiency is required. We have developed oxidized copper catalysts displaying lower overpotentials for carbon dioxide electroreduction and record selectivity towards ethylene (60%) through facile and tunable plasma treatments. Herein we provide insight into the improved performance of these catalysts by combining electrochemical measurements with microscopic and spectroscopic characterization techniques. Operando X-ray absorption spectroscopy and cross-sectional scanning transmission electron microscopy show that copper oxides aremore » surprisingly resistant to reduction and copper + species remain on the surface during the reaction. Furthermore, our results demonstrate that the roughness of oxide-derived copper catalysts plays only a partial role in determining the catalytic performance, while the presence of copper + is key for lowering the onset potential and enhancing ethylene selectivity.« less

Surface-rain interactions: differences in copper runoff for copper sheet of different inclination, orientation, and atmospheric exposure conditions.

PubMed

Hedberg, Yolanda S; Goidanich, Sara; Herting, Gunilla; Wallinder, Inger Odnevall

2015-01-01

Predictions of the diffuse dispersion of metals from outdoor constructions such as roofs and facades are necessary for environmental risk assessment and management. An existing predictive model has been compared with measured data of copper runoff from copper sheets exposed at four different inclinations facing four orientations at two different urban sites (Stockholm, Sweden, and Milan, Italy) during a 4-year period. Its applicability has also been investigated for copper sheet exposed at two marine sites(Cadiz, Spain, for 5 years, and Brest, France, for 9 years). Generally the model can be used for all given conditions. However, vertical surfaces should be considered as surfaces inclined 60-80 due to wind driven effects. The most important parameters that influence copper runoff, and not already included in the model, are the wind and rain characteristics that influence the actual rainfall volume impinging the surface of interest.

A Comparison of the Validity of the Five-Factor Model (FFM) Personality Disorder Prototypes Using FFM Self-Report and Interview Measures

ERIC Educational Resources Information Center

Miller, Joshua D.; Bagby, R. Michael; Pilkonis, Paul A.

2005-01-01

Recent studies have demonstrated that personality disorders (PDs) can be assessed via a prototype-matching technique, which enables researchers and clinicians to match an individual's five-factor model (FFM) personality profile to an expert-generated prototype. The current study examined the relations between these prototype scores, using…

Increase in the Quantum Yield of Photoinhibition Contributes to Copper Toxicity in Vivo1

PubMed Central

Pätsikkä, Eija; Aro, Eva-Mari; Tyystjärvi, Esa

1998-01-01

The effect of copper on photoinhibition of photosystem II in vivo was studied in bean (Phaseolus vulgaris L. cv Dufrix). The plants were grown hydroponically in the presence of various concentrations of Cu2+ ranging from the optimum 0.3 μm (control) to 15 μm. The copper concentration of leaves varied according to the nutrient medium from a control value of 13 mg kg−1 dry weight to 76 mg kg−1 dry weight. Leaf samples were illuminated in the presence and absence of lincomycin at different light intensities (500–1500 μmol photons m−2 s−1). Lincomycin prevents the concurrent repair of photoinhibitory damage by blocking chloroplast protein synthesis. The photoinhibitory decrease in the light-saturated rate of O2 evolution measured from thylakoids isolated from treated leaves correlated well with the decrease in the ratio of variable to maximum fluorescence measured from the leaf discs; therefore, the fluorescence ratio was used as a routine measurement of photoinhibition in vivo. Excess copper was found to affect the equilibrium between photoinhibition and repair, resulting in a decrease in the steady-state concentration of active photosystem II centers of illuminated leaves. This shift in equilibrium apparently resulted from an increase in the quantum yield of photoinhibition (ΦPI) induced by excess copper. The kinetic pattern of photoinhibition and the independence of ΦPI on photon flux density were not affected by excess copper. An increase in ΦPI may contribute substantially to Cu2+ toxicity in certain plant species. PMID:9625715

Prototypes reflect normative perceptions: implications for the development of reasoned action theory.

PubMed

Hennessy, Michael; Bleakley, Amy; Ellithorpe, Morgan

2018-03-01

The reasoned action approach is one of the most successful behavioral theories in the history of social psychology. This study outlines the theoretical principles of reasoned action and considers when it is appropriate to augment it with a new variable. To demonstrate, we use survey data collected from a 4 to 17 year old U.S. adolescents to test how the 'prototype' variables fit into reasoned action approach. Through confirmatory factor analysis, we find that the prototype measures are normative pressure measures and when treated as a separate theoretical construct, prototype identity is not completely mediated by the proximal predictors of behavioral intention. We discuss the assumptions of the two theories and finally consider the distinction between augmenting a specific theory versus combining measures derived from different theoretical perspectives.

[Use of copper oxide wire particles (Copinox) for the prevention of congenital copper deficiency in a herd of German Improved Fawn breed of goat].

PubMed

Winter, P; Hochsteiner, W; Chizzola, R

2004-10-01

In a herd of German Improved Fawn breed of goat in the year 2000 neonatal kid losses due to congenital copper deficiencies were observed. To clarify the problems and to prevent losses in the next breeding season serum copper levels of 10 dams and four control Boer goats were investigated at four time points during one year. Additionally ten kids of the following year were sampled and the serum copper levels were studied. Immediatly after parturition and 8 weeks later the dams showed low serum copper levels (10.4 +/- 11.1 micromol/l, 5.7 +/- 2.9 micromol/l resp.). At the end of the pasture season an increase of serum copper could be measured (19.3 +/- 16.0 micromol/l). To prevent enzootic ataxia due to congenital copper deficiency, the dams were treated with copper oxide wire particles in the next late gestation. At this time point serum copper concentrations started to decrease (18.5 +/- 8.4 micromol/l). The re-examination 3 month later demonstrated an increase of the serum mean copper concentrations up to 23.4 micromol/l in the dams and to 16.2 micromol/l in the kids. The serum copper levels were significantly higher compared to the levels the year before. Big variation of the serum copper levels in the control Boer goats occurred during the year, but no clinical symptoms of copper deficiency could be observed. The copper levels in the grass and soil samples were 6.8 mg/kg and 0.2 mg/kg dry substance, respectively. A secondary copper deficiency based on cadmium could be excluded through the low levels of soil samples. The contents of sulphur and molybdenum were not determined. The results indicate that the German Improved Fawn breed of goats suffered from a primary copper deficiency due to the inefficient mineral supplementation. The administration of Copinox in the last third of the gestation leads to a continious raising of the copper concentrations in the serum and is suited to prevent ataxia due to congential copper deficiency in neonatal kids.

Failure Analysis of Pitted Copper Pipes Used in Underground Water and Preventive Measures

NASA Astrophysics Data System (ADS)

Nam, Gi-ho; Lee, Jong-kwon; Kim, Kyung-ja

2018-05-01

This study performed an experiment on the causes of pitting corrosion in a copper tubing used for a sprinkler system. Corrosion products of a copper tubing that sustained pitting corrosion were collected and cultured in Culture medium [Luria-Bertani, Brain heart infusion, Tryptic soy broth (TSB), R2A]. Four types of bacteria were found through identification: Micrococcus luteus sp (species)., Staphylococcus sp., Sphingomonas sp., and Bacillus sp. The copper toxicity test was performed for each microorganism. Among the four microorganisms, Micrococcus luteus sp. showed good growth in the environment containing copper ions. On the immersion test, changes in pH and Optical density were measured; On the inductively coupled plasma optical emission spectrometry test, the copper concentration of each culture medium was measured. The surface of each copper sample was observed using a scanning electron microscope. The corrosion potential of a copper sample, after 48 h exposure of the TSB medium containing Micrococcus luteus sp., was measured using a potentiodynamic polarization experiment. The next experiment was conducted to prevent microbial corrosion by suppressing the growth of microorganisms. Six 30 ml TSB culture media with controlled pH value of 4, 5, 6, 7, 8, and 9 through HCl and NaOH were manufactured. Then the microorganisms were cultured in 37 °C 133 rpm, of which the growth status was checked every 24 h for 3 days. It was found that microorganisms did not grow on culture media with the pH value of 6 and lower. The same experiment conducted on culture media controlled with acetic acid, nitric acid, and sulfuric acid, also showed no growth of microorganisms on media with pH value of 6 and lower. Six 5 ml TSB culture media each containing 0.5, 0.25, 0.125, 0.0625, 0.0312%, and 0.0156% NaOCl and NaOBr as germicides were manufactured. 0.01 μl of microorganisms were inoculated on the media and cultured in 37 °C for 48 h. It was found that microorganisms did not grow in media with NaOCl and NaOBr concentration of 0.0625% and higher. Therefore, it can be suggested that in environments with pH value of 6 or lower, or NaOCl and NaOBr concentration of higher than 0.0625% suppresses microbial growth, thereby preventing microbial corrosion.

Failure Analysis of Pitted Copper Pipes Used in Underground Water and Preventive Measures

NASA Astrophysics Data System (ADS)

Nam, Gi-ho; Lee, Jong-kwon; Kim, Kyung-ja

2018-03-01

This study performed an experiment on the causes of pitting corrosion in a copper tubing used for a sprinkler system. Corrosion products of a copper tubing that sustained pitting corrosion were collected and cultured in Culture medium [Luria-Bertani, Brain heart infusion, Tryptic soy broth (TSB), R2A]. Four types of bacteria were found through identification: Micrococcus luteus sp (species)., Staphylococcus sp., Sphingomonas sp., and Bacillus sp. The copper toxicity test was performed for each microorganism. Among the four microorganisms, Micrococcus luteus sp. showed good growth in the environment containing copper ions. On the immersion test, changes in pH and Optical density were measured; On the inductively coupled plasma optical emission spectrometry test, the copper concentration of each culture medium was measured. The surface of each copper sample was observed using a scanning electron microscope. The corrosion potential of a copper sample, after 48 h exposure of the TSB medium containing Micrococcus luteus sp., was measured using a potentiodynamic polarization experiment. The next experiment was conducted to prevent microbial corrosion by suppressing the growth of microorganisms. Six 30 ml TSB culture media with controlled pH value of 4, 5, 6, 7, 8, and 9 through HCl and NaOH were manufactured. Then the microorganisms were cultured in 37 °C 133 rpm, of which the growth status was checked every 24 h for 3 days. It was found that microorganisms did not grow on culture media with the pH value of 6 and lower. The same experiment conducted on culture media controlled with acetic acid, nitric acid, and sulfuric acid, also showed no growth of microorganisms on media with pH value of 6 and lower. Six 5 ml TSB culture media each containing 0.5, 0.25, 0.125, 0.0625, 0.0312%, and 0.0156% NaOCl and NaOBr as germicides were manufactured. 0.01 μl of microorganisms were inoculated on the media and cultured in 37 °C for 48 h. It was found that microorganisms did not grow in media with NaOCl and NaOBr concentration of 0.0625% and higher. Therefore, it can be suggested that in environments with pH value of 6 or lower, or NaOCl and NaOBr concentration of higher than 0.0625% suppresses microbial growth, thereby preventing microbial corrosion.

Materials Development for Auxiliary Components for Large Compact Mo/Au TES Arrays

NASA Technical Reports Server (NTRS)

Finkbeiner, F. m.; Chervenak, J. A.; Bandler, S. R.; Brekosky, R.; Brown, A. D.; Figueroa-Feliciano, E.; Iyomoto, N.; Kelley, R. L.; Kilbourne, C. A.; Porter, F. S.;

In vitro inhibition of hyaluronidase by sodium copper chlorophyllin complex and chlorophyllin analogs

PubMed Central

McCook, John P; Dorogi, Peter L; Vasily, David B; Cefalo, Dustin R

2015-01-01

Background Inhibitors of hyaluronidase are potent agents that maintain hyaluronic acid homeostasis and may serve as anti-aging, anti-inflammatory, and anti-microbial agents. Sodium copper chlorophyllin complex is being used therapeutically as a component in anti-aging cosmeceuticals, and has been shown to have anti-hyaluronidase activity. In this study we evaluated various commercial lots of sodium copper chlorophyllin complex to identify the primary small molecule constituents, and to test various sodium copper chlorophyllin complexes and their small molecule analog compounds for hyaluronidase inhibitory activity in vitro. Ascorbate analogs were tested in combination with copper chlorophyllin complexes for potential additive or synergistic activity. Materials and methods For hyaluronidase activity assays, dilutions of test materials were evaluated for hydrolytic activity of hyaluronidase by precipitation of non-digested hyaluronate by measuring related turbidity at 595 nm. High-performance liquid chromatography and mass spectroscopy was used to analyze and identify the primary small molecule constituents in various old and new commercial lots of sodium copper chlorophyllin complex. Results The most active small molecule component of sodium copper chlorophyllin complex was disodium copper isochlorin e4, followed by oxidized disodium copper isochlorin e4. Sodium copper chlorophyllin complex and copper isochlorin e4 disodium salt had hyaluronidase inhibitory activity down to 10 µg/mL. The oxidized form of copper isochlorin e4 disodium salt had substantial hyaluronidase inhibitory activity at 100 µg/mL but not at 10 µg/mL. Ascorbate derivatives did not enhance the hyaluronidase inhibitory activity of sodium copper chlorophyllin. Copper isochlorin e4 analogs were always the dominant components of the small molecule content of the commercial lots tested; oxidized copper isochlorin e4 was found in increased concentrations in older compared to newer lots tested. Conclusion These results support the concept of using the hyaluronidase inhibitory activity of sodium copper chlorophyllin complex to increase the hyaluronic acid level of the dermal extracellular matrix for the improvement of the appearance of aging facial skin. PMID:26300653

In vitro inhibition of hyaluronidase by sodium copper chlorophyllin complex and chlorophyllin analogs.

PubMed

McCook, John P; Dorogi, Peter L; Vasily, David B; Cefalo, Dustin R

2015-01-01

Inhibitors of hyaluronidase are potent agents that maintain hyaluronic acid homeostasis and may serve as anti-aging, anti-inflammatory, and anti-microbial agents. Sodium copper chlorophyllin complex is being used therapeutically as a component in anti-aging cosmeceuticals, and has been shown to have anti-hyaluronidase activity. In this study we evaluated various commercial lots of sodium copper chlorophyllin complex to identify the primary small molecule constituents, and to test various sodium copper chlorophyllin complexes and their small molecule analog compounds for hyaluronidase inhibitory activity in vitro. Ascorbate analogs were tested in combination with copper chlorophyllin complexes for potential additive or synergistic activity. For hyaluronidase activity assays, dilutions of test materials were evaluated for hydrolytic activity of hyaluronidase by precipitation of non-digested hyaluronate by measuring related turbidity at 595 nm. High-performance liquid chromatography and mass spectroscopy was used to analyze and identify the primary small molecule constituents in various old and new commercial lots of sodium copper chlorophyllin complex. The most active small molecule component of sodium copper chlorophyllin complex was disodium copper isochlorin e4, followed by oxidized disodium copper isochlorin e4. Sodium copper chlorophyllin complex and copper isochlorin e4 disodium salt had hyaluronidase inhibitory activity down to 10 µg/mL. The oxidized form of copper isochlorin e4 disodium salt had substantial hyaluronidase inhibitory activity at 100 µg/mL but not at 10 µg/mL. Ascorbate derivatives did not enhance the hyaluronidase inhibitory activity of sodium copper chlorophyllin. Copper isochlorin e4 analogs were always the dominant components of the small molecule content of the commercial lots tested; oxidized copper isochlorin e4 was found in increased concentrations in older compared to newer lots tested. These results support the concept of using the hyaluronidase inhibitory activity of sodium copper chlorophyllin complex to increase the hyaluronic acid level of the dermal extracellular matrix for the improvement of the appearance of aging facial skin.

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

Yewondwossen, M; Robar, J; Parsons, D

Purpose: During radiotherapy treatment, lung tumors can display substantial respiratory motion. This motion usually necessitates enlarged treatment margins to provide full tumour coverage. Unfortunately, these margins limit the dose that can be prescribed for tumour control and cause complications to normal tissue. Options for real-time methods of direct detection of tumour position, and particularly those that obviate the need for inserted fiducial markers, are limited. We propose a method of tumor tracking without implanted fiducial markers using a novel fast switching-target that toggles between a FFF copper/tungsten therapy mode and a FFF low-Z target mode for imaging. In this workmore » we demonstrate proof-of-concept of this new technology. Methods: The prototype includes two targets: i) a FFF copper/tungsten target equivalent to that in the Varian 2100 EX 6 MV, and ii) a low-Z (carbon) target with a thickness of 110% of continuous slowing down approximation range (CSDA) at 7 MeV. The two targets can be exchanged with a custom made linear slide and motor-driven actuator. The usefulness of the switching-target concept is demonstrated through experimental BEV Planar images acquired with continual treatment and imaging at a user-defined period. Results: The prototype switching-target demonstrates that two recent advances in linac technology (FFF target for therapy and low-Z target) can be combined with synergy. The switching-target approach offers the capacity for rapid switching between treatment and high-contrast imaging modes, allowing intrafractional tracking, as demonstrated in this work with dynamic breathing phantom. By using a single beam-line, the design is streamlined and may obviate the need for an auxiliary imaging system (e.g., kV OBI.) Conclusion: This switching-target approach is a feasible combination of two current advances in linac technology (FFF target for therapy and a FFF low-Z target) allowing new options in on-line IGRT.« less

Total Copper Analyzer for Rapid In Situ Characterization of Effluent Discharges

DTIC Science & Technology

2006-10-03

acidification , digestion, and measurement of copper with a specialized jalpaite copper ion-selective electrode (Cu-ISE). The preprocessed sensor data...analysis. This is in contrast to the temperature conditions at SBWWTP, where the TCA was deployed in a plastic hut on open grounds. The daily range...GFAA Spectroscopy” (U.S. EPA, 1992). In order to accomplish this goal, the TCA includes in-line automatic acidification , fast digestion of the

Sulfidation treatment of copper-containing plating sludge towards copper resource recovery.

PubMed

Kuchar, D; Fukuta, T; Onyango, M S; Matsuda, H

2006-11-02

The present study is concerned with the sulfidation treatment of copper-containing plating sludge towards copper resource recovery by flotation of copper sulfide from treated sludge. The sulfidation treatment was carried out by contacting simulated or real copper plating sludge with Na(2)S solution for a period of 5 min to 24 h. The initial molar ratio of S(2-) to Cu(2+) (S(2-) to Me(2+) in the case of real sludge) was adjusted to 1.00, 1.25 or 1.50, while the solid to liquid ratio was set at 1:50. As a result, it was found that copper compounds were converted to various copper sulfides within the first 5 min. In the case of simulated copper sludge, CuS was identified as the main sulfidation product at the molar ratio of S(2-) to Cu(2+) of 1.00, while Cu(7)S(4) (Roxbyite) was mainly found at the molar ratios of S(2-) to Cu(2+) of 1.50 and 1.25. Based on the measurements of oxidation-reduction potential, the formation of either CuS or Cu(7)S(4) at different S(2-) to Cu(2+) molar ratios was attributed to the changes in the oxidation-reduction potential. By contrast, in the case of sulfidation treatment of real copper sludge, CuS was predominantly formed, irrespective of S(2-) to Me(2+) molar ratio.

The effects of soil liming and sewage sludge application on dynamics of copper fractions and total copper concentration.

PubMed

Malinowska, Elżbieta

2016-10-01

The paper deals with effects of liming and different doses of municipal sewage sludge (5, 10, and 15 % of soil mass) on copper speciation in soil. In all samples, pH was determined together with total copper concentration, which was measured with the ICP-AES method. Concentration of copper chemical fractions was determined using the seven-step procedure of Zeien and Brümmer. In the soil treated with the highest dose of sludge (15 %), there was, compared to the control, a twofold increase in the concentration of copper and a threefold increase in the concentration of nitrogen. Copper speciation analysis showed that in the municipal sewage sludge the easily soluble and exchangeable fractions (F1 and F2) constituted only a small share of copper with the highest amount of this metal in the organic (F4) and residual (F7) fractions. In the soil, at the beginning of the experiment, the highest share was in the organic fraction (F4), the residual fraction (F7) but also in the fraction where copper is bound to amorphous iron oxides (F5). After 420 days, at the end of the experiment, the highest amount of copper was mainly in the organic fraction (F4) and in the fraction with amorphous iron oxides (F5). Due to mineralization of organic matter in the sewage sludge, copper was released into the soil with the share of the residual fraction (F7) decreasing. In this fraction, there was much more copper in limed soil than in non-limed soil.

Arabidopsis copper transport protein COPT2 participates in the cross talk between iron deficiency responses and low-phosphate signaling.

PubMed

Perea-García, Ana; Garcia-Molina, Antoni; Andrés-Colás, Nuria; Vera-Sirera, Francisco; Pérez-Amador, Miguel A; Puig, Sergi; Peñarrubia, Lola

2013-05-01

Copper and iron are essential micronutrients for most living organisms because they participate as cofactors in biological processes, including respiration, photosynthesis, and oxidative stress protection. In many eukaryotic organisms, including yeast (Saccharomyces cerevisiae) and mammals, copper and iron homeostases are highly interconnected; yet, such interdependence is not well established in higher plants. Here, we propose that COPT2, a high-affinity copper transport protein, functions under copper and iron deficiencies in Arabidopsis (Arabidopsis thaliana). COPT2 is a plasma membrane protein that functions in copper acquisition and distribution. Characterization of the COPT2 expression pattern indicates a synergic response to copper and iron limitation in roots. We characterized a knockout of COPT2, copt2-1, that leads to increased resistance to simultaneous copper and iron deficiencies, measured as reduced leaf chlorosis and improved maintenance of the photosynthetic apparatus. We propose that COPT2 could play a dual role under iron deficiency. First, COPT2 participates in the attenuation of copper deficiency responses driven by iron limitation, possibly to minimize further iron consumption. Second, global expression analyses of copt2-1 versus wild-type Arabidopsis plants indicate that low-phosphate responses increase in the mutant. These results open up new biotechnological approaches to fight iron deficiency in crops.

Detection of Cu2+ in Water Based on Histidine-Gold Labeled Multiwalled Carbon Nanotube Electrochemical Sensor

PubMed Central

Zhu, Rilong; Zhou, Gangqiang; Tang, Fengxia; Wang, Yeyao

2017-01-01

Based on the strong interaction between histidine and copper ions and the signal enhancement effect of gold-labeling carbon nanotubes, an electrochemical sensor is established and used to measure copper ions in river water. In this study the results show that the concentrations of copper ion have well linear relationship with the peak current in the range of 10−11–10−7 mol/L, and the limit of detection is 10−12 mol/L. When using this method to detect copper ions in the Xiangjiang River, the test results are consistent with the atomic absorption method. This study shows that the sensor is convenient to be used in daily monitoring of copper ions in river water. PMID:28408929

Quenching characteristics of bathocuproinedisulfonic acid, disodium salt in aqueous solution and copper sulfate plating solution

NASA Astrophysics Data System (ADS)

Koga, Toshiaki; Hirakawa, Chieko; Takeshita, Michinori; Terasaki, Nao

2018-04-01

Bathocuproinedisulfonic acid, disodium salt (BCS) is generally used to detect Cu(I) through a color reaction. We newly found BCS fluorescence in the visible blue region in an aqueous solution. However, the fluorescence mechanism of BCS is not well known, so we should investigate its fundamental information. We confirmed that the characteristics of fluorescence are highly dependent on the molecular concentration and solvent properties. In particular, owing to the presence of the copper compound, the fluorescence intensity extremely decreases. By fluorescence quenching, we observed that a copper compound concentration of 10-6 mol/L or less could easily be measured in an aqueous solution. We also observed BCS fluorescence in copper sulfate plating solution and the possibility of detecting monovalent copper by fluorescence reabsorption.

Laser synthesis of a copper-single-walled carbon nanotube nanocomposite via molecular-level mixing and non-equilibrium solidification

NASA Astrophysics Data System (ADS)

Tu, Jay F.; Rajule, Nilesh; Molian, Pal; Liu, Yi

2016-12-01

A copper-single-walled carbon nanotube (Cu-SWCNT) metal nanocomposite could be an ideal material if it can substantially improve the strength of copper while preserving the metal’s excellent thermal and electrical properties. However, synthesis of such a nanocomposite is highly challenging, because copper and SWCNTs do not form intermetallic compounds and are insoluble; as a result, there are serious issues regarding wettability and fine dispersion of SWCNTs within the copper matrix. In this paper we present a novel wet process, called the laser surface implantation process (LSI), to synthesize Cu-SWCNT nanocomposites by mixing SWCNTs into molten copper. The LSI process includes drilling several microholes on a copper substrate, filling the microholes with SWCNTs suspended in solution, and melting the copper substrate to create a micro-well of molten copper. The molten copper advances radially outward to engulf the microholes with pre-deposited SWCNTs to form the Cu-SWCNT implant upon solidification. Rapid and non-equilibrium solidification is achieved due to copper’s excellent heat conductivity, so that SWCNTs are locked in position within the copper matrix without agglomerating into large clusters. This wet process is very different from the typical dry processes used in powder metallurgy. Very high hardness improvement, up to 527% over pure copper, was achieved, confirmed by micro-indentation tests, with only a 0.23% SWCNT volume fraction. The nanostructure of the nanocomposite was characterized by TEM imaging, energy-dispersive x-ray spectroscopy mapping and spectroscopy measurements. The SWCNTs were found to be finely dispersed within the copper matrix with cluster sizes in the range of nanometers, achieving the goal of molecular-level mixing.

Neutron diffraction measurements and modeling of residual strains in metal matrix composites

NASA Technical Reports Server (NTRS)

Saigal, A.; Leisk, G. G.; Hubbard, C. R.; Misture, S. T.; Wang, X. L.

1996-01-01

Neutron diffraction measurements at room temperature are used to characterize the residual strains in tungsten fiber-reinforced copper matrix, tungsten fiber-reinforced Kanthal matrix, and diamond particulate-reinforced copper matrix composites. Results of finite element modeling are compared with the neutron diffraction data. In tungsten/Kanthal composites, the fibers are in compression, the matrix is in tension, and the thermal residual strains are a strong function of the volume fraction of fibers. In copper matrix composites, the matrix is in tension and the stresses are independent of the volume fraction of tungsten fibers or diamond particles and the assumed stress free temperature because of the low yield strength of the matrix phase.

Clinical relevance of trace element measurement in patients on initiation of parenteral nutrition.

PubMed

Salota, Rashim; Omar, Sohail; Sherwood, Roy A; Raja, Kishor; Vincent, Royce P

2016-11-01

Background and Aims Serum zinc, copper and selenium are measured in patients prior to commencing on parenteral nutrition; however, their interpretation can be difficult due to acute phase reactions. We assessed (i) the relationship of raised C-reactive protein with trace elements and albumin (ii) benefits of measuring trace elements when C-reactive protein is raised in patients requiring short-term parenteral nutrition. Methods Samples were collected for zinc, copper, selenium and albumin at baseline and then every two weeks and correlated with C-reactive protein results in patients on parenteral nutrition. Results were categorized into four groups based on the C-reactive protein concentrations: (i) <20 mg/L, (ii) 20-39 mg/L, (iii) 40-79 mg/L and (iv) ≥80 mg/L. Results In 166 patients, zinc, selenium and albumin correlated (Spearman's) negatively with C-reactive protein; r = -0.26, P < 0.001 (95% CI -0.40 to -0.11), r = -0.44, P < 0.001 (-0.56 to -0.29) and r = -0.22 P = 0.005 (-0.36 to -0.07), respectively. Copper did not correlate with C-reactive protein (r = 0.09, P = 0.25 [-0.07 to 0.25]). Comparison of trace elements between the four groups showed no difference in zinc and copper (both P > 0.05), whereas selenium and albumin were lower in the group with C-reactive protein > 40 mg/L ( P < 0.05). Conclusion In patients on short-term parenteral nutrition, measurement of C-reactive protein is essential when interpreting zinc and selenium but not copper results. Routine measurement of trace elements prior to commencing parenteral nutrition has to be considered on an individual basis in patients with inflammation.

Performance of timing Resistive Plate Chambers with protons from 200 to 800 MeV

NASA Astrophysics Data System (ADS)

Machado, J.; Adamczewski-Musch, J.; Blanco, A.; Boretzky, K.; Cabanelas, P.; Cartegni, L.; Ferreira Marques, R.; Fonte, P.; Fruehauf, J.; Galaviz, D.; Heil, M.; Henriques, A.; . Ickert, G.; Körper, D.; Lopes, L.; Palka, M.; Pereira, A.; Rossi, D.; Simon, H.; Teubig, P.; Traxler, M.; Velho, P.; Altstadt, S.; Atar, L.; Aumann, T.; Bemmerer, D.; Caesar, C.; Charpy, A.; Elekes, Z.; Fiori, E.; Gasparic, I.; Gerbig, J.; Göbel, K.; Heftrich, T.; Heine, M.; Heinz, A.; Holl, M.; Ignatov, A.; Isaak, J.; Johansson, H.; Kelic-Heil, A.; Lederer, C.; Lindberg, S.; Löher, B.; Marganiec, J.; Martensson, M.; Nilsson, T.; Panin, V.; Paschalis, S.; Petri, M.; Plag, R.; Pohl, M.; Rastrepina, G.; Reifarth, R.; Reinhardt, T. P.; Röder, M.; Savran, D.; Scheit, H.; Schrock, P.; Silva, J.; Stach, D.; Strannerdahl, F.; Thies, R.; Wagner, A.; Wamers, F.; Weigand, M.

2015-01-01

A prototype composed of four resistive plate chamber layers has been exposed to quasi-monoenergetic protons produced from a deuteron beam of varying energy (200 to 800 AMeV) in experiment S406 at GSI, Darmstadt, Germany. The aim of the experiment is to characterize the response of the prototype to protons in this energy range, which deposit from 1.75 to 6 times more energy than minimum ionizing particles. Each layer, with an active area of about 2000 × 500 mm2, is made of modules containing the active gaps, all in multigap construction. Each gap is defined by 0.3 mm nylon mono-filaments positioned between 2.85 mm thick float glass electrodes. The modules are operated in avalanche mode with a non-flammable gas mixture composed of 90% C2H2F4 and 10% SF6. The signals are readout by a pick-up electrode formed by 15 copper strips (per layer), spaced at a pitch of 30 mm, connected at both sides to timing front end electronics. Results show an uniform efficiency close to 100% along with a timing resolution of around 60 ps on the entire 2000 × 500 mm2 area.

Multi-Mode Cavity Accelerator Structure

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

Jiang, Yong; Hirshfield, Jay Leonard

2016-11-10

This project aimed to develop a prototype for a novel accelerator structure comprising coupled cavities that are tuned to support modes with harmonically-related eigenfrequencies, with the goal of reaching an acceleration gradient >200 MeV/m and a breakdown rate <10 -7/pulse/meter. Phase I involved computations, design, and preliminary engineering of a prototype multi-harmonic cavity accelerator structure; plus tests of a bimodal cavity. A computational procedure was used to design an optimized profile for a bimodal cavity with high shunt impedance and low surface fields to maximize the reduction in temperature rise ΔT. This cavity supports the TM010 mode and its 2ndmore » harmonic TM011 mode. Its fundamental frequency is at 12 GHz, to benchmark against the empirical criteria proposed within the worldwide High Gradient collaboration for X-band copper structures; namely, a surface electric field E sur max< 260 MV/m and pulsed surface heating ΔT max< 56 °K. With optimized geometry, amplitude and relative phase of the two modes, reductions are found in surface pulsed heating, modified Poynting vector, and total RF power—as compared with operation at the same acceleration gradient using only the fundamental mode.« less

Construction and first beam-tests of silicon-tungsten prototype modules for the CMS High Granularity Calorimeter for HL-LHC

NASA Astrophysics Data System (ADS)

Jain, S.

2017-03-01

The High Granularity Calorimeter (HGCAL) is the technology choice of the CMS collaboration for the endcap calorimetry upgrade planned to cope with the harsh radiation and pileup environment at the High Luminosity-LHC . The HGCAL is realized as a sampling calorimeter, including an electromagnetic compartment comprising 28 layers of silicon pad detectors with pad areas of 0.5-01. cm2 interspersed with absorbers made from tungsten and copper to form a highly compact and granular device. Prototype modules, based on hexagonal silicon pad sensors, with 128 channels, have been constructed and tested in beams at FNAL and at CERN. The modules include many of the features required for this challenging detector, including a PCB glued directly to the sensor, using through-hole wire-bonding for signal readout and 5 mm spacing between layers—including the front-end electronics and all services. Tests in 2016 have used an existing front-end chip —Skiroc2 (designed for the CALICE experiment for ILC). We present results from first tests of these modules both in the laboratory and with beams of electrons, pions and protons, including noise performance, calibration with mips and electron signals.

Increased iron supplied through Fet3p results in replicative life span extension of Saccharomyces cerevisiae under conditions requiring respiratory metabolism.

PubMed

Botta, Gabriela; Turn, Christina S; Quintyne, Nicholas J; Kirchman, Paul A

2011-10-01

We have previously shown that copper supplementation extends the replicative life span of Saccharomyces cerevisiae when grown under conditions forcing cells to respire. We now show that copper's effect on life span is through Fet3p, a copper containing enzyme responsible for high affinity transport of iron into yeast cells. Life span extensions can also be obtained by supplementing the growth medium with 1mM ferric chloride. Extension by high iron levels is still dependent on the presence of Fet3p. Life span extension by iron or copper requires growth on media containing glycerol as the sole carbon source, which forces yeast to respire. Yeast grown on glucose containing media supplemented with iron show no extension of life span. The iron associated with cells grown in media supplemented with copper or iron is 1.4-1.8 times that of cells grown without copper or iron supplementation. As with copper supplementation, iron supplementation partially rescues the life span of superoxide dismutase mutants. Cells grown with copper supplementation display decreased production of superoxide as measured by dihydroethidium staining. Copyright © 2011 Elsevier Inc. All rights reserved.

Three techniques for the fabrication of high precision, mm-sized metal components based on two-photon lithography, applied for manufacturing horn antennas for THz transceivers

NASA Astrophysics Data System (ADS)

Standaert, Alexander; Brancato, Luigi; Lips, Bram; Ceyssens, Frederik; Puers, Robert; Reynaert, Patrick

2018-03-01

This paper proposes a novel packaging solution which integrates micro-machined 3D horn antennas with millimeter-wave and THz tranceivers. This packaging solution is shown to be a valid competitor to existing technologies like metallic split-block waveguides and low temperature cofired ceramics. Three different fabrication methods based on two-photon lithography are presented to form the horn antennas. The first uses two-photon lithography to form the bulk of the antenna. This structure is then metalised through physical vapor deposition (PVD) and copper plating. The second fabrication method makes use of a soft polydimethylsiloxane (PDMS) mold to easily replicate structures and the third method forms the horn antenna through electroforming. A prototype is accurately positioned on top of a 400 GHz 28 nm CMOS transmitter and glued in place with epoxy, thus providing a fully packaged solution. Measurement results show a 12 dB increase in the antenna gain when using the packaged solution. The fabrication processes are not limited to horn antennas alone and can be used to form a wide range of mm-sized metal components.

Fully gapped superconductivity with no sign change in the prototypical heavy-fermion CeCu2Si2.

PubMed

Yamashita, Takuya; Takenaka, Takaaki; Tokiwa, Yoshifumi; Wilcox, Joseph A; Mizukami, Yuta; Terazawa, Daiki; Kasahara, Yuichi; Kittaka, Shunichiro; Sakakibara, Toshiro; Konczykowski, Marcin; Seiro, Silvia; Jeevan, Hirale S; Geibel, Christoph; Putzke, Carsten; Onishi, Takafumi; Ikeda, Hiroaki; Carrington, Antony; Shibauchi, Takasada; Matsuda, Yuji

2017-06-01

In exotic superconductors, including high- T c copper oxides, the interactions mediating electron Cooper pairing are widely considered to have a magnetic rather than a conventional electron-phonon origin. Interest in this exotic pairing was initiated by the 1979 discovery of heavy-fermion superconductivity in CeCu 2 Si 2 , which exhibits strong antiferromagnetic fluctuations. A hallmark of unconventional pairing by anisotropic repulsive interactions is that the superconducting energy gap changes sign as a function of the electron momentum, often leading to nodes where the gap goes to zero. We report low-temperature specific heat, thermal conductivity, and magnetic penetration depth measurements in CeCu 2 Si 2 , demonstrating the absence of gap nodes at any point on the Fermi surface. Moreover, electron irradiation experiments reveal that the superconductivity survives even when the electron mean free path becomes substantially shorter than the superconducting coherence length. This indicates that superconductivity is robust against impurities, implying that there is no sign change in the gap function. These results show that, contrary to long-standing belief, heavy electrons with extremely strong Coulomb repulsions can condense into a fully gapped s-wave superconducting state, which has an on-site attractive pairing interaction.

Persistence of Mixed and Non-intermediate Valence in the High-Pressure Structure of Silver(I,III) Oxide, AgO: A Combined Raman, X-ray Diffraction (XRD), and Density Functional Theory (DFT) Study.

PubMed

Grzelak, Adam; Gawraczyński, Jakub; Jaroń, Tomasz; Somayazulu, Maddury; Derzsi, Mariana; Struzhkin, Viktor; Grochala, Wojciech

2017-05-15

The X-ray diffraction data collected up to ca. 56 GPa and the Raman spectra measured up to 74.8 GPa for AgO, or Ag I Ag III O 2 , which is a prototypical mixed valence (disproportionated) oxide, indicate that two consecutive phase transitions occur: the first-order phase transition occurs between 16.1 GPa and 19.7 GPa, and a second-order phase transition occurs at ca. 40 GPa. All polymorphic forms host the square planar [Ag III O 4 ] units typical of low-spin Ag III . The disproportionated Imma form persists at least up to 74.8 GPa, as indicated by Raman spectra. Theoretical hybrid density functional theory (DFT) calculations show that the first-order transition is phonon-driven. AgO stubbornly remains disproportionated up to at least 100 GPa-in striking contrast to its copper analogue-and the fundamental band gap of AgO is ∼0.3 eV at this pressure and is weakly pressure-dependent. Metallization of AgO is yet to be achieved.

Interactions of metallic substances and acidic ground water in the New Jersey Coastal Plan

USGS Publications Warehouse

Barringer, J.L.

1994-01-01

Four ancillary studies were undertaken in support of an investigation into the extent and distribution of corrosive ground water in the Kirkwood- Cohansey aquifer system of southern New Jersey.The ancillary studies were (1) analysis of tap-water samples for metals and the acquisition of metal data from a county study, (2) leaching experiments in which copper pipe with various types of solder were exposed to a variety of ground-water types, (3) analysis of pipe-scale deposits on plumbing from houses with wells that tap the Kirkwood-Cohansey aquifer system, and (4) measurement of corrosion rates for carbon steel and copper exposed to shallow ground water from the Kirkwood-Cohansey aquifer system. The results studies indicate that substantial concentrations of lead, copper, and zinc can leach from plumbing materials exposed to corrosive water from the Kirkwood-Cohansey aquifer system, and that leaching appears more pronounced during the summer than during the winter. The leaching experiments indicate that the corrosiveness of water, as estimated by the calculation of a corrosion index (the Aggressive Index), is related to the concentration of trace metals in the leachate.Further, although the leaching of lead-bearing solders produced lead concentrations in leachate above the Primary Drinking Water Criterion in effect at the time of the study (50 micrograms per liter), no potentially toxic levels of metals were leached from lead-free solders, although copper concentrations in some leachate samples were in excess of the Secondary Drinking Water Criterion of 1,000 micrograms per liter. Analyses of pipe-scale deposits indicate the formation of iron oxide coatings on some copper-pipe interiors exposed to untreated well water. Treated water from a public-supply system precipitated copper carbonate and copper chloride minerals. Corrosion rates measured for copper exposed to corrosive water from the Kirkwood-Cohansey aquifer system were slow (less than 0.0254 millimeters per year). Carbon-steel corrosion rates were faster; the fastest rate (0.229 millimeters per year) was measured in oxygen-saturated water.

Copper signaling in the brain and beyond.

PubMed

Ackerman, Cheri M; Chang, Christopher J

2018-03-30

Transition metals have been recognized and studied primarily in the context of their essential roles as structural and metabolic cofactors for biomolecules that compose living systems. More recently, an emerging paradigm of transition-metal signaling, where dynamic changes in transitional metal pools can modulate protein function, cell fate, and organism health and disease, has broadened our view of the potential contributions of these essential nutrients in biology. Using copper as a canonical example of transition-metal signaling, we highlight key experiments where direct measurement and/or visualization of dynamic copper pools, in combination with biochemical, physiological, and behavioral studies, have deciphered sources, targets, and physiological effects of copper signals.

Synthesis, spectroscopic and thermal studies of the copper(II) aspartame chloride complex

NASA Astrophysics Data System (ADS)

Çakır, S.; Coşkun, E.; Naumov, P.; Biçer, E.; Bulut, İ.; İçbudak, H.; Çakır, O.

2002-08-01

Aspartame adduct of copper(II) chloride Cu(Asp) 2Cl 2·2H 2O (Asp=aspartame) is synthesized and characterized by elemental analysis, FT IR, UV/vis, ESR spectroscopies, TG, DTG, DTA measurements and molecular mechanics calculations. Aqueous solution of the green solid absorbs strongly at 774 and 367 nm. According to the FT IR spectra, the aspartame moiety coordinates to the copper(II) ion via its carboxylate ends, whereas the ammonium terminal groups give rise to hydrogen bonding network with the water, the chloride ions or neighboring carboxylate groups. The results suggest tetragonally distorted octahedral environment of the copper ions.

Cadmium, copper, iron, and zinc concentrations in kidneys of grey wolves, Canis lupus, from Alaska, Idaho, Montana (USA) and the Northwest Territories (Canada).

PubMed

Hoffmann, S R; Blunck, S A; Petersen, K N; Jones, E M; Koval, J C; Misek, R; Frick, J A; Cluff, H D; Sime, C A; McNay, M; Beckman, K B; Atkinson, M W; Drew, M; Collinge, M D; Bangs, E E; Harper, R G

2010-11-01

Cadmium, copper, iron, and zinc levels were measured in the kidneys of 115 grey wolves (Canis lupus) from Idaho, Montana and Alaska (United States), and from the Northwest Territories (Canada). No significant differences in the levels of iron or copper were observed between locations, but wolf kidneys from more northern locations had significantly higher cadmium levels (Alaska > Northwest Territories > Montana ≈ Idaho), and wolves from Alaska showed significantly higher zinc than other locations. Additionally, female wolves in Alaska had higher iron levels than males, and adult wolves in Montana had higher copper levels than subadults.

Susceptibility cancellation of a microcoil wound with a paramagnetic-liquid-filled copper capillary

NASA Astrophysics Data System (ADS)

Takeda, Kazuyuki; Takasaki, Tomoya; Takegoshi, K.

2015-09-01

Even though microcoils improve the sensitivity of NMR measurement of tiny samples, magnetic-field inhomogeneity due to the bulk susceptibility effect of the coil material can cause serious resonance-line broadening. Here, we propose to fabricate the microcoil using a thin, hollow copper capillary instead of a wire and fill paramagnetic liquid inside the capillary, so as to cancel the diamagnetic contribution of the copper. Susceptibility cancellation is demonstrated using aqueous solution of NiSO4. In addition, the paramagnetic liquid serves as coolant when it is circulated through the copper capillary, effectively transferring the heat generated by radiofrequency pulses.

Structural measurements and cell line studies of the copper-PEG-Rifampicin complex against Mycobacterium tuberculosis.

PubMed

Manning, Thomas; Mikula, Rachel; Wylie, Greg; Phillips, Dennis; Jarvis, Jackie; Zhang, Fengli

2015-02-01

The bacterium responsible for tuberculosis is increasing its resistance to antibiotics resulting in new multidrug-resistant Mycobacterium tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB). In this study, several analytical techniques including NMR, FT-ICR, MALDI-MS, LC-MS and UV/Vis are used to study the copper-Rifampicin-Polyethylene glycol (PEG-3350) complex. The copper (II) cation is a carrier for the antibiotic Rifampicin as well as nutrients for the bacterium. The NIH-NIAID cell line containing several Tb strains (including antibiotic resistant strains) is tested against seven copper-PEG-RIF complex variations. Copyright © 2014 Elsevier Ltd. All rights reserved.

Accumulation and effects of copper on aquatic macrophytes Potamogeton pectinatus L.: Potential application to environmental monitoring and phytoremediation.

PubMed

Costa, Marcela Brandão; Tavares, Francesca Valêncio; Martinez, Claudia Bueno; Colares, Ioni Gonçalves; Martins, Camila de Martinez Gaspar

2018-07-15

This study investigated the ability of Potamogeton pectinatus L. to accumulate copper and its effects on plants. In accumulation tests, macrophytes were exposed (96 h) to different copper concentrations (0-1000 µM) and the metal was measured in media and plant tissues (roots, stems and leaves) to determine the bioconcentration factor (BCF). Plants accumulated high concentrations of copper in a dose-dependent manner and roots was the main organ for copper accumulation. However, the more copper increased in water, the more BCF values decreased. It may be due to either saturation of copper uptake or down-regulation of metal uptake by plants. In the physiological and morphological analyses, plants were kept (96 h) in Hoagland nutrient solution without copper, in full Hoagland solution (0.5 µM Cu) and in Hoagland medium with copper from 1 to 100 µM. The absence and the presence of copper above to 1 µM inhibited photosynthesis. Chlorophylls and carotenoid levels also decreased with the excess of copper, a fact that may have affected the photosystem II-dependent of chlorophyll and caused photosynthesis suppression. Only macrophytes at 10 µM Cu showed decrease in length and number of leaves on the 10th day of the test, when they died. Chlorosis and necrosis were observed in control groups and groups with extra copper, but not in Hoalgand group. Overall, the macrophyte P. pectinatus can be considered a suitable plant for monitoring environments contaminated by copper, based on results of copper accumulation in the plant, decrease in pigment concentration and presence of chlorosis and necrosis. However, values of BCF based on fresh water tissues was not proper to indicate the use of P. pectinatus for cleaning environments contaminated by copper. Copyright © 2018 Elsevier Inc. All rights reserved.

Modeling, design, and testing of a proof-of-concept prototype damper with friction and eddy current damping effects

NASA Astrophysics Data System (ADS)

Amjadian, Mohsen; Agrawal, Anil K.

2018-01-01

Friction is considered as one of the most reliable mechanisms of energy dissipation that has been utilized extensively in passive damping devices to mitigate vibration of civil engineering structures subjected to extreme natural hazards such as earthquakes and windstorms. However, passive friction dampers are well-known for having a highly nonlinear hysteretic behavior caused by stick-slip motion at low velocities, a phenomenon that is inherent in friction and increases the acceleration response of the structure under control unfavorably. The authors have recently proposed the theoretical concept of a new type of damping device termed as "Passive Electromagnetic Eddy Current Friction Damper" (PEMECFD) in which an eddy current damping mechanism was utilized not only to decrease the undesirable effects of stick-slip motion, but also to increase the energy dissipation capacity of the damping device as a whole. That study was focused on demonstration of the theoretical performance of the proposed damping device through numerical simulations. This paper further investigates the influence of eddy current damping on energy dissipation due to friction through modeling, design, and testing of a proof-of-concept prototype damper. The design of this damper has been improved over the design in the previous study. The normal force in this damper is produced by the repulsive magnetic force between two cuboidal permanent magnets (PMs) magnetized in the direction normal to the direction of the motion. The eddy current damping force is generated because of the motion of the two PMs and two additional PMs relative to a copper plate in their vicinity. The dynamic models for the force-displacement relationship of the prototype damper are based on LuGre friction model, electromagnetic theory, and inertial effects of the prototype damper. The parameters of the dynamic models have been identified through a series of characterization tests on the prototype damper under harmonic excitations of different frequencies in the laboratory. Finally, the identified dynamic models have been validated by subjecting the prototype damper to two different random excitations. The results indicate that the proposed dynamic models are capable of representing force-displacement behavior of the new type of passive damping device for a wide range of operating conditions.

Copper plasmonics and catalysis: role of electron-phonon interactions in dephasing localized surface plasmons

NASA Astrophysics Data System (ADS)

Sun, Qi-C.; Ding, Yuchen; Goodman, Samuel M.; H. Funke, Hans; Nagpal, Prashant

2014-10-01

Copper metal can provide an important alternative for the development of efficient, low-cost and low-loss plasmonic nanoparticles, and selective nanocatalysts. However, poor chemical stability and lack of insight into photophysics and plasmon decay mechanisms has impeded study. Here, we use smooth conformal ALD coating on copper nanoparticles to prevent surface oxidation, and study dephasing time for localized surface plasmons on different sized copper nanoparticles. Using dephasing time as a figure of merit, we elucidate the role of electron-electron, electron-phonon, impurity, surface and grain boundary scattering on the decay of localized surface plasmon waves. Using our quantitative analysis and different temperature dependent measurements, we show that electron-phonon interactions dominate over other scattering mechanisms in dephasing plasmon waves. While interband transitions in copper metal contributes substantially to plasmon losses, tuning surface plasmon modes to infrared frequencies leads to a five-fold enhancement in the quality factor. These findings demonstrate that conformal ALD coatings can improve the chemical stability for copper nanoparticles, even at high temperatures (>300 °C) in ambient atmosphere, and nanoscaled copper is a good alternative material for many potential applications in nanophotonics, plasmonics, catalysis and nanoscale electronics.Copper metal can provide an important alternative for the development of efficient, low-cost and low-loss plasmonic nanoparticles, and selective nanocatalysts. However, poor chemical stability and lack of insight into photophysics and plasmon decay mechanisms has impeded study. Here, we use smooth conformal ALD coating on copper nanoparticles to prevent surface oxidation, and study dephasing time for localized surface plasmons on different sized copper nanoparticles. Using dephasing time as a figure of merit, we elucidate the role of electron-electron, electron-phonon, impurity, surface and grain boundary scattering on the decay of localized surface plasmon waves. Using our quantitative analysis and different temperature dependent measurements, we show that electron-phonon interactions dominate over other scattering mechanisms in dephasing plasmon waves. While interband transitions in copper metal contributes substantially to plasmon losses, tuning surface plasmon modes to infrared frequencies leads to a five-fold enhancement in the quality factor. These findings demonstrate that conformal ALD coatings can improve the chemical stability for copper nanoparticles, even at high temperatures (>300 °C) in ambient atmosphere, and nanoscaled copper is a good alternative material for many potential applications in nanophotonics, plasmonics, catalysis and nanoscale electronics. Electronic supplementary information (ESI) available. See DOI: 10.1039/c4nr04719b

FAST TRACK COMMUNICATION High rate straining of tantalum and copper

NASA Astrophysics Data System (ADS)

Armstrong, R. W.; Zerilli, F. J.

2010-12-01

High strain rate measurements reported recently for several tantalum and copper crystal/polycrystal materials are shown to follow dislocation mechanics-based constitutive relations, first at lower strain rates, for dislocation velocity control of the imposed plastic deformations and, then at higher rates, transitioning to nano-scale dislocation generation control by twinning or slip. For copper, there is the possibility of added-on slip dislocation displacements to be accounted for from the newly generated dislocations.

Identification and Description of Geophysical Techniques.

DTIC Science & Technology

1980-11-01

electrodes are used for voltage measurements with the potentiometer. Current elec- trodes may be stainless-steel or copper rods, buried copper screens, drill...steel in a borehole, or buried metal culverts. Potential elec- trodes may be stainless steel rods or porous containers filled with copper sulfate...Granite 28-2,700 Diorite 47 Gabbro 68-2,370 Porphyry 47 Diabase 78-1,050 Basalt 680 Olivine-Diabase 2,000 1. Peridotite 12,500 I (1)Adapted from C. A

Measurement of electron-ion relaxation in warm dense copper

DOE PAGES

Cho, B. I.; Ogitsu, T.; Engelhorn, K.; ...

2016-01-06

Experimental investigation of electron-ion coupling and electron heat capacity of copper in warm and dense states are presented. From time-resolved x-ray absorption spectroscopy, the temporal evolution of electron temperature is obtained for non-equilibrium warm dense copper heated by an intense femtosecond laser pulse. Electron heat capacity and electron-ion coupling are inferred from the initial electron temperature and its decrease over 10 ps. As a result, data are compared with various theoretical models.

Disulphide linkage: To get cleaved or not? Bulk and nano copper based SERS of cystine

NASA Astrophysics Data System (ADS)

P. J., Arathi; Seemesh, Bhaskar; Rajendra Kumar Reddy, G.; Suresh Kumar, P.; Ramanathan, V.

2018-05-01

Different nano-structures of noble metals have been the conventional substrates for carrying out Surface Enhanced Raman Spectroscopy (SERS). In this paper we examine electrodeposited copper (Cu) nano-structures on pencil graphite as novel substrate to carry out SERS measurements by considering L-cystine (Cys-Cys) (dimer of the amino acid cysteine) as the probe. The formation of monolayer of the probe molecule on the substrates was confirmed using cyclic voltammetric measurements. Mode of adsorption of Cys-Cys was observed to be different on bulk Cu (taken in the wire form) and nano-structured Cu on pencil graphite. Whereas in the former the disulphide bond of Cys-Cys remained intact, it got cleaved when Cys-Cys was adsorbed on electrodeposited copper indicating the activated nature of the nano-structure compared to bulk copper. Csbnd S stretching mode of vibration underwent blue shift in Cys-Cys adsorbed on Cu on pencil graphite vis-à-vis Cys-Cys adsorbed on Cu wire. Further evidence on the cleavage of the Csbnd S bond on an activated substrate was obtained by considering a bimetallic substrate comprising of silver on copper which was electrodeposited on pencil graphite. Our studies have demonstrated that nano-copper surface is an excellent substrate for SERS giving 200 μM as lower detection limit for Cys-Cys.

Fiber laser welding of austenitic steel and commercially pure copper butt joint

NASA Astrophysics Data System (ADS)

Kuryntsev, S. V.; Morushkin, A. E.; Gilmutdinov, A. Kh.

2017-03-01

The fiber laser welding of austenitic stainless steel and commercially pure copper in butt joint configuration without filler or intermediate material is presented. In order to melt stainless steel directly and melt copper via heat conduction a defocused laser beam was used with an offset to stainless steel. During mechanical tests the weld seam was more durable than heat affected zone of copper so samples without defects could be obtained. Three process variants of offset of the laser beam were applied. The following tests were conducted: tensile test of weldment, intermediate layer microhardness, optical metallography, study of the chemical composition of the intermediate layer, fractography. Measurements of electrical resistivity coefficients of stainless steel, copper and copper-stainless steel weldment were made, which can be interpreted or recalculated as the thermal conductivity coefficient. It shows that electrical resistivity coefficient of cooper-stainless steel weldment higher than that of stainless steel. The width of intermediate layer between stainless steel and commercially pure copper was 41-53 μm, microhardness was 128-170 HV0.01.

Effect of copper on the scope for growth of clams (Tapes philippinarum) from a farming area in the Northern Adriatic Sea.

PubMed

Munari, Cristina; Mistri, Michele

2007-09-01

Copper is currently the most common biocide in antifouling paints. Levels of this metal were measured in the water, particulate matter and sediments from a shellfish farming area in the Sacca di Goro (Northern Adriatic Sea) over one year. With respect to the 1980s, copper environmental level increased twofold. The release of copper from shellfish farmers' boats was also estimated to be > 250 kg Cu y(-1). Clams Tapes philippinarum were collected in the same area and seasonally exposed to a sublethal (10 microg Cu l(-1)) concentration of copper. Physiological traits were significantly affected by copper exposure (scope for growth declined as a result of reduced clearance rate, increased oxygen consumption and a generally lower absorption efficiency). The results of this study are cause for concern for shellfish farming activities at least in Northern Adriatic, where shellfish farming is a monoculture of T. philippinarum. A strict interpretation of the precautionary principle might suggest that more rigorous regulatory action to control copper inputs in the field would be justified.

Organic Complexation of Dissolved Copper and Iron from Shipboard Incubations in the Central California Current System: Investigating the Impacts of Light Conditions and Phytoplankton Growth on Iron- and Copper-Binding Ligand Characteristics

NASA Astrophysics Data System (ADS)

Mellett, T.; Parker, C.; Brown, M.; Coale, T.; Duckham, C.; Chappell, D.; Maldonado, M. T.; Bruland, K. W.; Buck, K. N.

2016-02-01

Two shipboard incubation experiments were carried out in July of 2014 to investigate potential sources and sinks of iron- and copper-binding organic ligands in the surface ocean. Seawater for the experiments was collected from the central California Current System (cCCS) and incubated under varying light conditions and in the presence and absence of natural phytoplankton communities. Incubation treatments were sampled over a period of up to 3 days for measurements of total dissolved copper and iron, and for the concentration and conditional stability constants of copper- and iron-binding organic ligands. Dissolved copper and iron were determined by inductively coupled plasma-mass spectrometry (ICP-MS) following preconcentration on a Nobias PA1 resin. Organic ligand characteristics for iron and copper were determined using a method of competitive ligand exchange-absorptive cathodic stripping voltammetry (CLE-ACSV) with the added competing ligand salicylaldoxime. Trends in ligand concentrations and conditional stability constants across the different treatments and over the course of the incubation experiments will be presented.

Erythrocyte CuZn superoxide dismutase activity is decreased in iron-deficiency anemia.

PubMed

Olivares, M; Araya, M; Pizarro, F; Letelier, A

2006-09-01

Iron and copper are essential microminerals that are intimately related. The present study was performed to determine the effect of iron-deficiency anemia (IDA) and treatment with iron on laboratory indicators of copper status. Hemoglobin, mean corpuscular volume erythrocyte Zn protoporphyrin, serum ferritin, serum copper, serum ceruloplasmin, and erythrocyte CuZn-superoxide dismutase (SOD) activity were studied in 12 adult women with IDA before and after iron treatment for 60-90 d (100 mg/d Fe, as ferric polymaltose) and in 27 women with normal iron status. Prior to treatment with iron, serum copper and ceruloplasmin were not different between the groups and treatment with iron did not affect these measures. IDA women, before and after treatment with iron, presented a 2.9- and 2-fold decrease in erythrocyte CuZn-SOD activity compared to women with normal iron status (p < 0.001). Treatment with iron increased erythrocyte CuZn-SOD activity of the IDA group; however, this change was not statistically significant. In conclusion, CuZn-SOD activity is decreased in IDA. Measurement of this enzyme activity is not useful for evaluating copper nutrition in iron-deficient subjects.

Description of the prototype diagnostic residual gas analyzer for ITER.

PubMed

Younkin, T R; Biewer, T M; Klepper, C C; Marcus, C

2014-11-01

The diagnostic residual gas analyzer (DRGA) system to be used during ITER tokamak operation is being designed at Oak Ridge National Laboratory to measure fuel ratios (deuterium and tritium), fusion ash (helium), and impurities in the plasma. The eventual purpose of this instrument is for machine protection, basic control, and physics on ITER. Prototyping is ongoing to optimize the hardware setup and measurement capabilities. The DRGA prototype is comprised of a vacuum system and measurement technologies that will overlap to meet ITER measurement requirements. Three technologies included in this diagnostic are a quadrupole mass spectrometer, an ion trap mass spectrometer, and an optical penning gauge that are designed to document relative and absolute gas concentrations.

A Comprehensive Investigation and Coupler Design for Higher-Order Modes in the BNL Energy Recovery Linear Accelerator

NASA Astrophysics Data System (ADS)

Marques, Carlos

A next generation Energy Recovery Linac (ERL) is under development in the Collider-Accelerator Department at Brookhaven National Laboratory (BNL). This ERL uses a superconducting radio frequency (SFR) cavity to produce an electric field gradient ideal to accelerate charged particles. As with many accelerators, higher-order modes (HOMs) can be induced by a beam of charged particles traversing the linear accelerator cavity. The excitation of these modes can result in problematic single and multi-bunch effects and also produce undesirable heat loads to the cryogenic system. Understanding HOM prevalence and structure inside the accelerator cavity is crucial for devising a procedure for extracting HOM power and promoting excellent beam quality. In this work, a method was created to identify and characterize HOMs using a perturbation technique on a copper (Cu) cavity prototype of the BNL3 linac and a double lambda/4 crab cavity. Both analyses and correlation between simulated and measured results are shown. A coaxial to dual-ridge waveguide HOM coupler was designed, constructed and implemented to extract power from HOMs simultaneously making an evanescent fundamental mode for the BNL3 cavity. A full description of the design is given along with a simulated analysis of its performance. Comparison between previous HOM coupler designs as well as correspondence between simulation and measurement is also given.

A reliable control system for measurement on film thickness in copper chemical mechanical planarization system

NASA Astrophysics Data System (ADS)

Li, Hongkai; Qu, Zilian; Zhao, Qian; Tian, Fangxin; Zhao, Dewen; Meng, Yonggang; Lu, Xinchun

2013-12-01

In recent years, a variety of film thickness measurement techniques for copper chemical mechanical planarization (CMP) are subsequently proposed. In this paper, the eddy-current technique is used. In the control system of the CMP tool developed in the State Key Laboratory of Tribology, there are in situ module and off-line module for measurement subsystem. The in situ module can get the thickness of copper film on wafer surface in real time, and accurately judge when the CMP process should stop. This is called end-point detection. The off-line module is used for multi-points measurement after CMP process, in order to know the thickness of remained copper film. The whole control system is structured with two levels, and the physical connection between the upper and the lower is achieved by the industrial Ethernet. The process flow includes calibration and measurement, and there are different algorithms for two modules. In the process of software development, C++ is chosen as the programming language, in combination with Qt OpenSource to design two modules' GUI and OPC technology to implement the communication between the two levels. In addition, the drawing function is developed relying on Matlab, enriching the software functions of the off-line module. The result shows that the control system is running stably after repeated tests and practical operations for a long time.

A reliable control system for measurement on film thickness in copper chemical mechanical planarization system.

PubMed

Li, Hongkai; Qu, Zilian; Zhao, Qian; Tian, Fangxin; Zhao, Dewen; Meng, Yonggang; Lu, Xinchun

2013-12-01

In recent years, a variety of film thickness measurement techniques for copper chemical mechanical planarization (CMP) are subsequently proposed. In this paper, the eddy-current technique is used. In the control system of the CMP tool developed in the State Key Laboratory of Tribology, there are in situ module and off-line module for measurement subsystem. The in situ module can get the thickness of copper film on wafer surface in real time, and accurately judge when the CMP process should stop. This is called end-point detection. The off-line module is used for multi-points measurement after CMP process, in order to know the thickness of remained copper film. The whole control system is structured with two levels, and the physical connection between the upper and the lower is achieved by the industrial Ethernet. The process flow includes calibration and measurement, and there are different algorithms for two modules. In the process of software development, C++ is chosen as the programming language, in combination with Qt OpenSource to design two modules' GUI and OPC technology to implement the communication between the two levels. In addition, the drawing function is developed relying on Matlab, enriching the software functions of the off-line module. The result shows that the control system is running stably after repeated tests and practical operations for a long time.

A reliable control system for measurement on film thickness in copper chemical mechanical planarization system

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

Li, Hongkai; Qu, Zilian; Zhao, Qian

In recent years, a variety of film thickness measurement techniques for copper chemical mechanical planarization (CMP) are subsequently proposed. In this paper, the eddy-current technique is used. In the control system of the CMP tool developed in the State Key Laboratory of Tribology, there are in situ module and off-line module for measurement subsystem. The in situ module can get the thickness of copper film on wafer surface in real time, and accurately judge when the CMP process should stop. This is called end-point detection. The off-line module is used for multi-points measurement after CMP process, in order to knowmore » the thickness of remained copper film. The whole control system is structured with two levels, and the physical connection between the upper and the lower is achieved by the industrial Ethernet. The process flow includes calibration and measurement, and there are different algorithms for two modules. In the process of software development, C++ is chosen as the programming language, in combination with Qt OpenSource to design two modules’ GUI and OPC technology to implement the communication between the two levels. In addition, the drawing function is developed relying on Matlab, enriching the software functions of the off-line module. The result shows that the control system is running stably after repeated tests and practical operations for a long time.« less

Determination of kjeldahl nitrogen in fertilizers by AOAC official methods 978.02: effect of copper sulfate as a catalyst.

PubMed

Abrams, Dean; Metcalf, David; Hojjatie, Michael

2014-01-01

In AOAC Official Method 955.04, Nitrogen (Total) in Fertilizers, Kjeldahl Method, fertilizer materials are analyzed using mercuric oxide or metallic mercury HgO or Hg) as a catalyst. AOAC Official Methods 970.02, Nitrogen (Total) in Fertilizers is a comprehensive total nitrogen (including nitrate nitrogen) method adding chromium metal. AOAC Official Method 978.02, Nitrogen (Total) in Fertilizers is a modified comprehensive nitrogen method used to measure total nitrogen in fertilizers with two types of catalysts. In this method, either copper sulfate or chromium metal is added to analyze for total Kjeldahl nitrogen. In this study, the part of AOAC Official Method 978.02 that is for nitrate-free fertilizer products was modified. The objective was to examine the necessity of copper sulfate as a catalyst for the nitrate-free fertilizer products. Copper salts are not environmentally friendly and are considered pollutants. Products such as ammonium sulfate, diammonium phosphate, monoammonium phosphate, urea-containing fertilizers such as isobutylene diurea (IBDU), and urea-triazone fertilizer solutions were examined. The first part of the study was to measure Kjeldahl nitrogen as recommended by AOAC Official Method 978.02. The second part of the study was to exclude the addition of copper sulfate from AOAC Official Method 978.02 to examine the necessity of copper sulfate as a catalyst in nitrate-free fertilizers, which was the primary objective. Our findings indicate that copper sulfate can be eliminated from the method with no significant difference in the results for the nitrogen content of the fertilizer products.

Copper Complex in Poly(vinyl chloride) as a Nitric Oxide-Generating Catalyst for the Control of Nitrifying Bacterial Biofilms.

PubMed

Wonoputri, Vita; Gunawan, Cindy; Liu, Sanly; Barraud, Nicolas; Yee, Lachlan H; Lim, May; Amal, Rose

2015-10-14

In this study, catalytic generation of nitric oxide by a copper(II) complex embedded within a poly(vinyl chloride) matrix in the presence of nitrite (source of nitric oxide) and ascorbic acid (reducing agent) was shown to effectively control the formation and dispersion of nitrifying bacteria biofilms. Amperometric measurements indicated increased and prolonged generation of nitric oxide with the addition of the copper complex when compared to that with nitrite and ascorbic acid alone. The effectiveness of the copper complex-nitrite-ascorbic acid system for biofilm control was quantified using protein analysis, which showed enhanced biofilm suppression when the copper complex was used in comparison to that with nitrite and ascorbic acid treatment alone. Confocal laser scanning microscopy (CLSM) and LIVE/DEAD staining revealed a reduction in cell surface coverage without a loss of viability with the copper complex and up to 5 mM of nitrite and ascorbic acid, suggesting that the nitric oxide generated from the system inhibits proliferation of the cells on surfaces. Induction of nitric oxide production by the copper complex system also triggered the dispersal of pre-established biofilms. However, the addition of a high concentration of nitrite and ascorbic acid to a pre-established biofilm induced bacterial membrane damage and strongly decreased the metabolic activity of planktonic and biofilm cells, as revealed by CLSM with LIVE/DEAD staining and intracellular adenosine triphosphate measurements, respectively. This study highlights the utility of the catalytic generation of nitric oxide for the long-term suppression and removal of nitrifying bacterial biofilms.

Hygroscopic and Chemical Properties of Aerosols collected near a Copper Smelter: Implications for Public and Environmental Health

PubMed Central

Sorooshian, Armin; Csavina, Janae; Shingler, Taylor; Dey, Stephen; Brechtel, Fred J.; Sáez, A. Eduardo; Betterton, Eric A.

2012-01-01

Particulate matter emissions near active copper smelters and mine tailings in the southwestern United States pose a potential threat to nearby environments owing to toxic species that can be inhaled and deposited in various regions of the body depending on the composition and size of the particles, which are linked by particle hygroscopic properties. This study reports the first simultaneous measurements of size-resolved chemical and hygroscopic properties of particles next to an active copper smelter and mine tailings by the towns of Hayden and Winkelman in southern Arizona. Size-resolved particulate matter samples collected near an active copper smelter were examined with inductively coupled plasma mass spectrometry, ion chromatography, and a humidified tandem differential mobility analyzer. Aerosol particles collected at the measurement site are enriched in metals and metalloids (e.g. arsenic, lead, and cadmium) and water-uptake measurements of aqueous extracts of collected samples indicate that the particle diameter range of particles most enriched with these species (0.18–0.55 µm) overlaps with the most hygroscopic mode at a relative humidity of 90% (0.10–0.32 µm). These measurements have implications for public health, microphysical effects of aerosols, and regional impacts owing to the transport and deposition of contaminated aerosol particles. PMID:22852879

Investigation of an Ultrafast Harmonic Resonant RF Kicker

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

Huang, Yulu

An Energy Recovery Linac (ERL) based multi-turn electron Circulator Cooler Ring (CCR) is envisaged in the proposed Jefferson Lab Electron Ion Collider (JLEIC) to cool the ion bunches with high energy (55 MeV), high current (1.5 A), high repetition frequency (476.3 MHz), high quality magnetized electron bunches. A critical component in this scheme is a pair of ultrafast kickers for the exchange of electron bunches between the ERL and the CCR. The ultrafast kicker should operate with the rise and fall time in less than 2.1 ns, at the repetition rate of ~10s MHz, and should be able to runmore » continuously during the whole period of cooling. These -and-fall time being combined together, are well beyond the state-of-art of traditional pulsed power supplies and magnet kickers. To solve this technical challenge, an alternative method is to generate this high repetition rate, fast rise-and-fall time short pulse continuous waveform by summing several finite number of (co)sine waves at harmonic frequencies of the kicking repetition frequency, and these harmonic modes can be generated by the Quarter Wave Resonater (QWR) based multifrequency cavities. Assuming the recirculator factor is 10, 10 harmonic modes (from 47.63 MHz to 476.3 MHz) with proper amplitudes and phases, plus a DC offset are combined together, a continuous short pulse waveform with the rise-and-fall time in less than 2.1 ns, repetition rate of 47.63 MHz waveform can be generated. With the compact and matured technology of QWR cavities, the total cost of both hardware development and operation can be reduced to a modest level. Focuse on the technical scheme, three main topics will be discussed in this thesis: the synthetization of the kicking pulse, the design and optimization of the deflecting QWR multi-integer harmonic frequency resonator and the fabrication and bench measurements of a half scale copper prototype. In the kicking pulse synthetization part, we begin with the Fourier Series expansion of an ideal square pulse, and get a Flat-Top waveform which will give a uniform kick over the bunch length of the kicked electron bunches, thus the transverse emittance of these kicked electron bunches can be maintained. By using two identical kickers with the betatron phase advance of 180 degree or its odd multiples, the residual kick voltage wave slopes at the unkicked bunch position will be totally cancelled out. Flat-Top waveform combined with two kicker scheme, the transverse emittance of the cooling electron bunches will be conserved during the whole injection, recirculation, and ejection processes. In the cavity design part, firstly, the cavity geometry is optimized to get high transverse shunt impedance thus less than 100 W of RF losses on the cavity wall can be achieved for all these 10 harmonic modes. To support all these 10 harmonic modes, group of four QWRs are adopted with the mode distribution of 5:3:1:1. In the multi-frequency cavities such as the five-mode-cavity and the three-mode-cavity, tunings are required to achieve the design frequencies for each mode. Slight segments of taper design on the inner conductor help to get the frequencies to be exactly on the odd harmonic modes. Stub tuners equal to the number of resonant modes are inserted to the outer conductor wall to compensate the frequency shifts due manufacturing errors and other perturbations during the operation such as the change of the cavity temperature. Single loop couple is designed for all harmonic modes in each cavity. By adjusting its loop size, position and rotation, it is possible to get the fundamental mode critical coupled and other higher harmonic modes slightly over coupled. A broadband circulator will be considered for absorbing the reflected power. Finally in this part, multipole field components due to the asymmetric cylindrical structure around the beam axis of the cavity as well as the beam-induced higher order mode (HOM) issues will be analyzed and discussed in this thesis. A half-scale copper prototype cavity (resonant frequencies from 95.26 MHz to 857.34 MHz) was fabricated to validate the electromagnetic characteristics. With this half scale prototype, the tuning processes of multiple harmonic frequencies, unloaded quality factor measurements of each mode, and bead-pull measurements are performed. The bench measurement results matched well with the simulation results, which have validated our cavity design and construction methods. Finally, a simple mode combining experiment with five separate signal generators was performed on this prototype cavity and the desired fast rise/fall time (1.2 ns), high repetition rate (95.26 MHz) waveform was captured, which finally proved our design of this ultrafast harmonic kicker.« less

Measurements of serum non-ceruloplasmin copper by a direct fluorescent method specific to Cu(II).

PubMed

Squitti, Rosanna; Siotto, Mariacristina; Cassetta, Emanuele; El Idrissi, Imane Ghafir; Colabufo, Nicola A

2017-08-28

Meta-analyses indicated the breakdown of copper homeostasis in the sporadic form of Alzheimer's disease (AD), comprising copper decreases within the brain and copper increases in the blood and the pool not bound to ceruloplasmin (non-Cp Cu, also known in the literature as "free" copper). The calculated non-Cp Cu (Walshe's) index has many limitations. A direct fluorescent method for non-Cp Cu detection has been developed and data are presented herein. The study included samples from 147 healthy subjects, 36 stable mild cognitive impairment (MCI) and 89 AD patients, who were tested for non-Cp Cu through the direct method, total serum copper, ceruloplasmin concentration and o-dianisidine ceruloplasmin activity. The indirect non-Cp Cu Walshe's index was also calculated. The direct method was linear (0.9-5.9 μM), precise (within-laboratory coefficient variation of 9.7% for low and 7.1% for high measurements), and had a good recovery. A reference interval (0-1.9 μM) was determined parametrically in 147 healthy controls (27-84 years old). The variation of non-Cp Cu was evaluated according to age and sex. Non-Cp Cu was 1.5 times higher in AD patients (regarding the upper value of the reference interval) than in healthy controls. Healthy, MCI and AD subjects were differentiated through the direct non-Cp Cu method [areas under the curve (AUC)=0.755]. Considering a 95% specificity and a 1.91 μmol/L cut-off, the sensitivity was 48.3% (confidence interval 95%: 38%-58%). The likelihood ratio (LR) was 9.94 for positive test results (LR+) and 0.54 for negative test result (LR-). The direct fluorescent test reliably and accurately measures non-Cp Cu, thereby determining the probability of having AD.

Effect of Surface Preparation and Gas Flow on Nitrogen Atom Surface Recombination

NASA Technical Reports Server (NTRS)

Prok, George M.

1961-01-01

The effects of surface preparation and gas flow on the recombination of nitrogen atoms at copper and platinum surfaces were determined. Atoms were generated by an electrodeless 2450-megacycle-per-second discharge, and their concentration was measured by gas-phase titration with nitric oxide. Test surfaces were either vacuum-evaporated films or spheres machined from bulk metal and cemented around small glass-bead thermistors. Heat released by recombination was measured as the difference in electrical energy required to maintain a given thermistor temperature with and without a catalytic surface exposed. Recombination coefficients measured at flow velocities of 1120, 1790, 2250, and 3460 centimeters per second and at pressures of 0.42 and 0.59 millimeter of mercury showed that flow conditions had no effect. The results were also independent of atom concentration. A rough indication of the temperature dependence was obtained; it was greater for copper than for platinum. Platinum films deposited on platinum or on glass had the same activity - about 3 percent of the atoms impinging recombined. With copper, however, the glass substrate greatly reduced the percent of atoms recombining over that of a bulk copper substrate where 4 percent of the impinging atoms recombined. This effect could be overcome by depositing a second film on top of the first. Bulk metal samples were subjected to various surface treatments including polishing, degreasing with a chlorinated hydrocarbon, washing with nitric acid, and rinsing with water. Polished, degreased platinum had low activity compared to an evaporated film, but nitric acid treatment made it equivalent. Polished, degreased copper was only slightly less active than a copper film; nitric acid etching decreased the activity still further, probably by preferentially exposing facets of low catalytic efficiency.

A comparison of the validity of the five-factor model (FFM) personality disorder prototypes. Using FFM self-report and interview measures.

PubMed

Miller, Joshua D; Bagby, R Michael; Pilkonis, Paul A

2005-12-01

Recent studies have demonstrated that personality disorders (PDs) can be assessed via a prototype-matching technique, which enables researchers and clinicians to match an individual's five-factor model (FFM) personality profile to an expert-generated prototype. The current study examined the relations between these prototype scores, using interview and self-report data, and PD symptoms in an outpatient sample (N = 115). Both sets of PD prototype scores demonstrated significant convergent validity with PD symptom counts, suggesting that the FFM PD prototype scores are appropriate for use with both sources of data.

Diabetic cardiomyopathy is associated with defective myocellular copper regulation and both defects are rectified by divalent copper chelation

PubMed Central

2014-01-01

Background Heart disease is the leading cause of death in diabetic patients, and defective copper metabolism may play important roles in the pathogenesis of diabetic cardiomyopathy (DCM). The present study sought to determine how myocardial copper status and key copper-proteins might become impaired by diabetes, and how they respond to treatment with the Cu (II)-selective chelator triethylenetetramine (TETA) in DCM. Methods Experiments were performed in Wistar rats with streptozotocin (STZ)-induced diabetes with or without TETA treatment. Cardiac function was analyzed in isolated-perfused working hearts, and myocardial total copper content measured by particle-induced x-ray emission spectroscopy (PIXE) coupled with Rutherford backscattering spectrometry (RBS). Quantitative expression (mRNA and protein) and/or activity of key proteins that mediate LV-tissue-copper binding and transport, were analyzed by combined RT-qPCR, western blotting, immunofluorescence microscopy, and enzyme activity assays. Statistical analysis was performed using Student’s t-tests or ANOVA and p-values of < 0.05 have been considered significant. Results Left-ventricular (LV) copper levels and function were severely depressed in rats following 16-weeks’ diabetes, but both were unexpectedly normalized 8-weeks after treatment with TETA was instituted. Localized myocardial copper deficiency was accompanied by decreased expression and increased polymerization of the copper-responsive transition-metal-binding metallothionein proteins (MT1/MT2), consistent with impaired anti-oxidant defences and elevated susceptibility to pro-oxidant stress. Levels of the high-affinity copper transporter-1 (CTR1) were depressed in diabetes, consistent with impaired membrane copper uptake, and were not modified by TETA which, contrastingly, renormalized myocardial copper and increased levels and cell-membrane localization of the low-affinity copper transporter-2 (CTR2). Diabetes also lowered indexes of intracellular (IC) copper delivery via the copper chaperone for superoxide dismutase (CCS) to its target cuproenzyme, superoxide dismutase-1 (SOD1): this pathway was rectified by TETA treatment, which normalized SOD1 activity with consequent bolstering of anti-oxidant defenses. Furthermore, diabetes depressed levels of additional intracellular copper-transporting proteins, including antioxidant-protein-1 (ATOX1) and copper-transporting-ATPase-2 (ATP7B), whereas TETA elevated copper-transporting-ATPase-1 (ATP7A). Conclusions Myocardial copper deficiency and defective cellular copper transport/trafficking are revealed as key molecular defects underlying LV impairment in diabetes, and TETA-mediated restoration of copper regulation provides a potential new class of therapeutic molecules for DCM. PMID:24927960

Stacking Faults and Mechanical Behavior beyond the Elastic Limit of an Imidazole-Based Metal Organic Framework: ZIF-8.

PubMed

Hegde, Vinay I; Tan, Jin-Chong; Waghmare, Umesh V; Cheetham, Anthony K

2013-10-17

We determine the nonlinear mechanical behavior of a prototypical zeolitic imidazolate framework (ZIF-8) along two modes of mechanical failure in response to tensile and shear forces using first-principles simulations. Our generalized stacking fault energy surface reveals an intrinsic stacking fault of surprisingly low energy comparable to that in copper, though the energy barrier associated with its formation is much higher. The lack of vibrational spectroscopic evidence for such faults in experiments can be explained with the structural instability of the barrier state to form a denser and disordered state of ZIF-8 seen in our analysis, that is, large shear leads to its amorphization rather than formation of faults.

CuOF: an electrical to optical interface for the upgrade of the CMS muon Drift Tubes system

NASA Astrophysics Data System (ADS)

Dattola, D.; De Remigis, P.; Maselli, S.; Mazza, G.; Rotondo, F.; Wheadon, R.

2013-02-01

The upgrade of the Drift Tube system of the CMS experiment foresee the relocation of the electronics actually sitting on the racks beside the magnet from the cavern to the counting room. It is thus required to convert the signals from electrical to optical, for a total number of 3500 channels that run at up to 480 Mb/s. A Copper to Optical Fiber board is currently under design. The board is divided into a mother board, which hosts the slow control system based on Field Programmable Gate Array, and four mezzanine cards, each with 8 conversion channels. A prototype of the mezzanine board has been designed and tested under irradiation.

Fate and forms of Cu in a reservoir ecosystem following copper sulfate treatment (Saint Germain les Belles, France)

NASA Astrophysics Data System (ADS)

van Hullebusch, E.; Chatenet, P.; Deluchat, V.; Chazal, P. M.; Froissard, D.; Lens, P. N. L.; Baudu, M.

2003-05-01

Copper sulfate (CuSO4) addition to freshwater for phytoplankton control has been practiced for decades, and remains the most effective algicidal treatment for numerous managed water bodies. A reservoir in the centre of France was the site for an investigation of copper distribution in aquatic systems after a copper sulfate treatment Results of copper monitoring showed a rapid conversion of dissolved Cu to particulate forms, with significant accumulation in the sediments/83% of total copper added). Total sediment Cu content increasedfrom approximately 37.7 to 45.4 μg.g^{-1} dry weight after the first treatment. Sequential extraction suggested that a significanl portion of the sediment-borne Cu was associated with the organic fraction which may release Cu to the water column, although significant release would occur only under extreme changes in water chemistry. Based upon measured Cu concentrations, flows at the down-stream water, and known mass applied during treatment, mass balance calculations indicated that approximately 17% of the Cu was exported from the reservoir over a 70 day period following a 196 μg.L^{-l} Cu^{2+} (as CuSO4, 5 H2O) treatment. The largest amount of copper was probably adsorbed on downstream sediment or lost in running water, Copper bioaccumulation by a moss, Fontinalis antipyretica, in the down-stream water showed that it was possible to distinguish between a treated and an untreated area. The impact of copper treatment in the down-stream reservoir could be followed using mosses. The bioaccumulation data further showed that there is a distance effect which could be exploited to determine potential copper impact on receiving water bodies. Thirty days after copper sulfate addition, Fontinalis still indicated copper exposure.

In utero copper treatment for Menkes disease associated with a severe ATP7A mutation

PubMed Central

Haddad, Marie Reine; Macri, Charles J.; Holmes, Courtney S.; Goldstein, David S.; Jacobson, Beryl E.; Centeno, Jose A.; Popek, Edwina J.; Gahl, Willam A.; Kaler, Stephen G.

2012-01-01

Menkes disease is a lethal X-linked recessive neurodegenerative disorder of copper transport caused by mutations in ATP7A, which encodes a copper-transporting ATPase. Early postnatal treatment with copper injections often improves clinical outcomes in affected infants. While Menkes disease newborns appear normal neurologically, analyses of fetal tissues including placenta indicate abnormal copper distribution and suggest a prenatal onset of the metal transport defect. In an affected fetus whose parents found termination unacceptable and who understood the associated risks, we began in utero copper histidine treatment at 31.5 weeks gestational age. Copper histidine (900 μg per dose) was administered directly to the fetus by intramuscular injection (fetal quadriceps or gluteus) under ultrasound guidance. Percutaneous umbilical blood sampling enabled serial measurement of fetal copper and ceruloplasmin levels that were used to guide therapy over a four-week period. Fetal copper levels rose from 17 μg/dL prior to treatment to 45 μg/dL, and ceruloplasmin levels from 39 mg/L to 122 mg/L. After pulmonary maturity was confirmed biochemically, the baby was delivered at 35.5 weeks and daily copper histidine therapy (250 μg sc b.i.d.) was begun. Despite this very early intervention with copper, the infant showed hypotonia, developmental delay, and electroencephalographic abnormalities and died of respiratory failure at 5.5 months of age. The patient’s ATP7A mutation, which severely disrupted mRNA splicing, resulted in complete absence of ATP7A protein on Western blots. These investigations suggest that prenatally initiated copper replacement is inadequate to correct Menkes disease caused by severe loss-of-function mutations, and that postnatal ATP7A gene addition represents a rational approach in such circumstances. PMID:22695177

From Laboratory Research to a Clinical Trial

PubMed Central

Michels, Harold T.; Keevil, C. William; Salgado, Cassandra D.; Schmidt, Michael G.

2015-01-01

Objective: This is a translational science article that discusses copper alloys as antimicrobial environmental surfaces. Bacteria die when they come in contact with copper alloys in laboratory tests. Components made of copper alloys were also found to be efficacious in a clinical trial. Background: There are indications that bacteria found on frequently touched environmental surfaces play a role in infection transmission. Methods: In laboratory testing, copper alloy samples were inoculated with bacteria. In clinical trials, the amount of live bacteria on the surfaces of hospital components made of copper alloys, as well as those made from standard materials, was measured. Finally, infection rates were tracked in the hospital rooms with the copper components and compared to those found in the rooms containing the standard components. Results: Greater than a 99.9% reduction in live bacteria was realized in laboratory tests. In the clinical trials, an 83% reduction in bacteria was seen on the copper alloy components, when compared to the surfaces made from standard materials in the control rooms. Finally, the infection rates were found to be reduced by 58% in patient rooms with components made of copper, when compared to patients' rooms with components made of standard materials. Conclusions: Bacteria die on copper alloy surfaces in both the laboratory and the hospital rooms. Infection rates were lowered in those hospital rooms containing copper components. Thus, based on the presented information, the placement of copper alloy components, in the built environment, may have the potential to reduce not only hospital-acquired infections but also patient treatment costs. PMID:26163568

All-sky brightness monitoring of light pollution with astronomical methods.

PubMed

Rabaza, O; Galadí-Enríquez, D; Estrella, A Espín; Dols, F Aznar

2010-06-01

This paper describes a mobile prototype and a protocol to measure light pollution based on astronomical methods. The prototype takes three all-sky images using BVR filters of the Johnson-Cousins astronomical photometric system. The stars are then identified in the images of the Hipparcos and General Catalogue of Photometric Data II astronomical catalogues, and are used as calibration sources. This method permits the measurement of night-sky brightness and facilitates an estimate of which fraction is due to the light up-scattered in the atmosphere by a wide variety of man-made sources. This is achieved by our software, which compares the sky background flux to that of many stars of known brightness. The reduced weight and dimensions of the prototype allow the user to make measurements from virtually any location. This prototype is capable of measuring the sky distribution of light pollution, and also provides an accurate estimate of the background flux at each photometric band. (c) 2010 Elsevier Ltd. All rights reserved.

Copper in the intake and discharge zones of the Surry and Salem Nuclear Power Stations

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

Harrison, F.L.; Bishop, D.J.; Rice, D.W. Jr.

Copper concentrations were measured in the soluble and particulate fractions of water samples and bedload sediments collected in intake and discharge areas of the Surry and Salem Nuclear Power Stations during normal operations. Additional samples of water and suspended particles were collected during startup of Unit 2 at the Salem Power Station. In water samples collected from Surry, total copper ranged from 6.5 to 24.7 and labile copper from 0.5 to 2.9 ..mu..g/L; in those from Salem, total copper ranged from 6.7 to 10.6 and labile from 0.9 to 3.8 ..mu..g/L. At both sites the highest total copper concentration wasmore » measured in January 1979 during a period of high runoff. In general, differences between influent and effluent waters were small; the maximum was 4.2 ..mu..g Cu/L. Copper concentration in the water during startup of Unit 2 of Salem was high initially (>2500 ..mu..g Cu/L) but was almost entirely in the particulate fraction; labile copper was only 0.6 ..mu..g/L. The apparent complexing capacity (ACC) of the waters from Surry ranged from 6 to 40 and those from Salem from 5 to 60 ..mu..g Cu/L. Ranges in dissolved organic carbon were smaller, 2.9 to 5.1 and 2.2 to 5.0 mg C/L for Surry and Salem, respectively, and showed no relationship with ACC. Ultrafiltration of discharge waters indicated that, in most samples, the largest fraction of copper in the untreated water was in the >10,000 <100,000 molecular weight fraction; in waters treated to destroy dissolved organic carbon, it was generally in the >100,000 molecular weight fraction.Copper concentrations in intact bedload sediments from the intake area of Surry ranged from 2.3 to 26 and of Salem from 36 to 74 ..mu..g/g dry weight; those in the discharge area of Surry ranged from 13 to 30 and of Salem from 3 to 67. We noted considerable spatial heterogeneity both at the intake and discharge areas, and higher copper concentrations in the <62-..mu..m fraction than in intact sediments.« less

Copper induces expression and methylation changes of early development genes in Crassostrea gigas embryos.

PubMed

Sussarellu, Rossana; Lebreton, Morgane; Rouxel, Julien; Akcha, Farida; Rivière, Guillaume

2018-03-01

Copper contamination is widespread along coastal areas and exerts adverse effects on marine organisms such as mollusks. In the Pacific oyster, copper induces severe developmental abnormalities during early life stages; however, the underlying molecular mechanisms are largely unknown. This study aims to better understand whether the embryotoxic effects of copper in Crassostrea gigas could be mediated by alterations in gene expression, and the putative role of DNA methylation, which is known to contribute to gene regulation in early embryo development. For that purpose, oyster embryos were exposed to 4 nominal copper concentrations (0.1, 1, 10 and 20 μg L -1 Cu 2+ ) during early development assays. Embryotoxicity was monitored through the oyster embryo-larval bioassay at the D-larva stage 24 h post fertilization (hpf) and genotoxicity at gastrulation 7 hpf. In parallel, the relative expression of 15 genes encoding putative homeotic, biomineralization and DNA methylation proteins was measured at three developmental stages (3 hpf morula stage, 7 hpf gastrula stage, 24 hpf D-larvae stage) using RT-qPCR. Global DNA content in methylcytosine and hydroxymethylcytosine were measured by HPLC and gene-specific DNA methylation levels were monitored using MeDIP-qPCR. A significant increase in larval abnormalities was observed from copper concentrations of 10 μg L -1 , while significant genotoxic effects were detected at 1 μg L -1 and above. All the selected genes presented a stage-dependent expression pattern, which was impaired for some homeobox and DNA methylation genes (Notochord, HOXA1, HOX2, Lox5, DNMT3b and CXXC-1) after copper exposure. While global DNA methylation (5-methylcytosine) at gastrula stage didn't show significant changes between experimental conditions, 5-hydroxymethylcytosine, its degradation product, decreased upon copper treatment. The DNA methylation of exons and the transcript levels were correlated in control samples for HOXA1 but such a correlation was diminished following copper exposure. The methylation level of some specific gene regions (HoxA1, Hox2, Engrailed2 and Notochord) displayed changes upon copper exposure. Such changes were gene and exon-specific and no obvious global trends could be identified. Our study suggests that the embryotoxic effects of copper in oysters could involve homeotic gene expression impairment possibly by changing DNA methylation levels. Copyright © 2018 Elsevier B.V. All rights reserved.

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

Inglese, Alessandro, E-mail: alessandro.inglese@aalto.fi; Savin, Hele; Lindroos, Jeanette

Copper is a harmful metal impurity that significantly impacts the performance of silicon-based devices if present in active regions. In this contribution, we propose a fast method consisting of simultaneous illumination and annealing for the detection of copper contamination in p-type silicon. Our results show that, within minutes, such method is capable of producing a significant reduction of the minority carrier lifetime. A spatial distribution map of copper contamination can then be obtained through the lifetime values measured before and after degradation. In order to separate the effect of the light-activated copper defects from the other metastable complexes in lowmore » resistivity Cz-silicon, we carried out a dark anneal at 200 °C, which is known to fully recover the boron-oxygen defect. Similar to the boron-oxygen behavior, we show that the dark anneal also recovers the copper defects. However, the recovery is only partial and it can be used to identify the possible presence of copper contamination.« less

In Vitro Bioavailability of Calcium, Magnesium, Iron, Zinc, and Copper from Gluten-Free Breads Supplemented with Natural Additives.

PubMed

Regula, J; Cerba, A; Suliburska, J; Tinkov, A A

2018-03-01

The aim of this study was to measure the content of calcium, magnesium, iron, zinc, and copper and determine the bioavailability of these ingredients in gluten-free breads fortified with milk and selected seeds. Due to the increasing prevalence of celiac disease and mineral deficiencies, it has become necessary to produce food with higher nutritional values which maintains the appropriate product characteristics. This study was designed for gluten-free breads fortified with milk and seeds such as flax, poppy, sunflower seeds, pumpkin seeds or nuts, and flour with amaranth. Subsequently, digestion was performed in vitro and the potential bioavailability of the minerals was measured. In the case of calcium, magnesium, iron, and copper, higher bioavailability was observed in rice bread, and, in the case of copper and zinc, in buckwheat bread. This demonstrated a clear increase in bioavailability of all the minerals when the bread were enriched. However, satisfactory results are obtained only for the individual micronutrients.

Hydrogen transport behavior of metal coatings for plasma-facing components

NASA Astrophysics Data System (ADS)

Anderl, R. A.; Holland, D. F.; Longhurst, G. R.

1990-12-01

Plasma-facing components for experimental and commercial fusion reactor studies may include cladding or coatings of refractory metals like tungsten on metallic structural substrates such as copper, vanadium alloys and austenitic stainless steel. Issues of safety and fuel economy include the potential for inventory buildup and permeation of tritium implanted into the plasma-facing surface. This paper reports on laboratory-scale studies with 3 keV D +3 ion beams to investigate the hydrogen transport behavior in tungsten coatings on substrates of copper. These experiments entailed measurements of the deuterium re-emission and permeation rates for tungsten, copper, and tungsten-coated copper specimens at temperatures ranging from 638 to 825 K and implanting particle fluxes of approximately 5 × 10 19 D/m 2 s. Diffusion constants and surface recombination coefficients with enhancement factors due to sputtering were obtained from these measurements. These data may be used in calculations to estimate permeation rates and inventory buildups for proposed diverter designs.

Effects of copper on growth, metamorphosis and endocrine disruption of Bufo gargarizans larvae.

PubMed

Wang, Chao; Liang, Gang; Chai, Lihong; Wang, Hongyuan

2016-01-01

Chinese toad (Bufo gargarizans) tadpoles were exposed to copper (1, 6.4, 32 and 64μgL(-1) copper) from the beginning of larval period through completion of metamorphosis. We examined the effects of chronic copper exposure on mortality, growth, time to metamorphosis, tail resorption time, body size at the metamorphic climax (Gs 42) and completion of metamorphosis (Gs 46) and thyroid gland histology. In addition, type 2 and 3 iodothyronine deiodinase (Dio2 and Dio3), thyroid hormone receptors (TRα and TRβ) mRNA levels were also measured to assess disruption of TH synthesis. Our result showed that 6.4-64μgL(-1) copper concentration increased the mortality and inhibited the growth of B. gargarizans tadpoles. In addition, significant reduction in size at Gs 42 and a time delay to Gs 42 were observed at 6.4-64μgL(-1) copper treatments. Moreover, histological examinations have clearly revealed that 64μgL(-1) copper caused follicular cell hyperplasia in thyroid gland. According to real-time PCR results, exposure to 32 and 64μgL(-1) copper significantly up-regulated mRNA expression of Dio3, but down-regulated mRNA expression of TRα and TRβ mRNA level. We concluded that copper delayed amphibian metamorphosis through changing mRNA expression of Dio3, TRα and TRβ, which suggests that copper might have the endocrine-disrupting effect. Copyright © 2015 Elsevier B.V. All rights reserved.

In-situ real time measurements of net erosion rates of copper during hydrogen plasma exposure

NASA Astrophysics Data System (ADS)

Kesler, Leigh; Wright, Graham; Peterson, Ethan; Whyte, Dennis

2013-10-01

In order to properly understand the dynamics of net erosion/deposition in fusion reactors, such as tokamaks, a diagnostic measuring the real time rates of net erosion/deposition during plasma exposure is necessary. The DIONISOS experiment produces real time measurements of net erosion/deposition by using Rutherford backscattering spectroscopy (RBS) ion beam analysis simultaneously with plasma exposure from a helicon plasma source. This in-situ method improves on ex-situ weight loss measurements by allowing measurement of possible synergistic effects of high ion implantation rates and net erosion rate and by giving a real time response to changes in plasma parameters. Previous work has validated this new technique for measuring copper (Cu) erosion from helium (He) plasma ion bombardment. This technique is now extended to measure copper erosion due to deuterium and hydrogen plasma ion exposure. Targets used were a 1.5 μm Cu layer on an aluminum substrate. Cu layer thickness is tracked in real time using 1.2 MeV proton RBS. Measured erosion rates will be compared to results from literature and He erosion rates. Supported by US DoE award DE-SC00-02060.

Determining the Fate and Ecological Effects of Copper and Zinc Loading in Estuarine Environments: A Multi-Disciplinary Program

DTIC Science & Technology

2005-12-01

from Centro de Investigación Científica y de Estudios Avanzados de Ensenada. vii viii 1 EXECUTIVE...Fouling, San Diego, California, 21-26 July 2002. Seligman, P.F., A.O. Valkirs, J.S. Caso , I. Rivera-Duarte, and E. Haslbeck, 2001. Copper release rates...EPA-822-R-02-047. Valkirs, A.O., Seligman, P.F., Haslbeck, E., and Caso , J.S., 2003. Measurement of copper release rates from antifouling paint

Alloy Development, Processing and Characterization of Devitrified Titanium Base Microcrystalline Alloys.

DTIC Science & Technology

1984-12-01

quench rates (10V 10V [/sec). Since the heat transport and temperature profile of Ti melt in the cold copper crucible are not well known, melting...experiments in a cold copper crucible by arc heating were conducted using Ti-6.3Si alloy. The temperature measurement at both the surface and the bottom of the...melt spinning compart- ment B, and ribbon processing chamber C. The pre-melted alloy ingot is . - " charged directly into a cold copper crucible while

C-H oxidation and chelation of a dipyrromethane mediated rapid colorimetric naked-eye Cu(ii) chemosensor.

PubMed

Rajmohan, Rajamani; Ayaz Ahmed, Khan Behlol; Sangeetha, Sampathkumar; Anbazhagan, Veerappan; Vairaprakash, Pothiappan

2017-09-08

Copper(ii) ion mediated C-H oxidation of dipyrromethanes (DPMs) to the corresponding dipyrrins followed by complexation invoked the selective sensing of copper(ii) ions in aqueous solutions. On the addition of copper, the colour of the DPM solution instantaneously changes from yellow to pink with the detection limit of 0.104 μM measured by absorption spectroscopy, whereas visible colour changes could be observed by the naked eye for concentrations as low as 3 μM.

Long-distance connections in the Copper Age: New evidence from the Alpine Iceman’s copper axe

PubMed Central

Angelini, Ivana; Kaufmann, Günther; Canovaro, Caterina; Dal Sasso, Gregorio; Villa, Igor Maria

2017-01-01

25 years after the discovery in the Ötztal Italian Alps, the 5,300-year-old mummy keeps providing key information on human biological and medical conditions, aspects of everyday life and societal organization in the Copper Age. The hand axe found with the body of the Alpine Iceman is one of the rare copper objects that is firmly dated to the early Copper Age because of the radiocarbon dating of the axe wooden shaft. Here we report the measurement of the lead isotope ratios of the copper blade. The results unambiguously indicate that the source of the metal is the ore-rich area of Southern Tuscany, despite ample evidence that Alpine copper ore sources were known and exploited at the time. The experimental results are discussed within the framework of all the available coeval archaeometallurgical data in Central-Southern Europe: they show that the Alps were a neat cultural barrier separating distinct metal circuits. The direct evidence of raw metal or object movement between Central Italy and the Alps is surprising and provides a new perspective on long-distance relocation of goods and relationships between the early Copper Age cultures in the area. The result is in line with the recent investigations re-evaluating the timing and extent of copper production in Central Italy in the 4th millennium BC. PMID:28678801

Long-distance connections in the Copper Age: New evidence from the Alpine Iceman's copper axe.

PubMed

Artioli, Gilberto; Angelini, Ivana; Kaufmann, Günther; Canovaro, Caterina; Dal Sasso, Gregorio; Villa, Igor Maria

2017-01-01

25 years after the discovery in the Ötztal Italian Alps, the 5,300-year-old mummy keeps providing key information on human biological and medical conditions, aspects of everyday life and societal organization in the Copper Age. The hand axe found with the body of the Alpine Iceman is one of the rare copper objects that is firmly dated to the early Copper Age because of the radiocarbon dating of the axe wooden shaft. Here we report the measurement of the lead isotope ratios of the copper blade. The results unambiguously indicate that the source of the metal is the ore-rich area of Southern Tuscany, despite ample evidence that Alpine copper ore sources were known and exploited at the time. The experimental results are discussed within the framework of all the available coeval archaeometallurgical data in Central-Southern Europe: they show that the Alps were a neat cultural barrier separating distinct metal circuits. The direct evidence of raw metal or object movement between Central Italy and the Alps is surprising and provides a new perspective on long-distance relocation of goods and relationships between the early Copper Age cultures in the area. The result is in line with the recent investigations re-evaluating the timing and extent of copper production in Central Italy in the 4th millennium BC.

Arabidopsis Copper Transport Protein COPT2 Participates in the Cross Talk between Iron Deficiency Responses and Low-Phosphate Signaling1[C][W

PubMed Central

Perea-García, Ana; Garcia-Molina, Antoni; Andrés-Colás, Nuria; Vera-Sirera, Francisco; Pérez-Amador, Miguel A.; Puig, Sergi; Peñarrubia, Lola

2013-01-01

Copper and iron are essential micronutrients for most living organisms because they participate as cofactors in biological processes, including respiration, photosynthesis, and oxidative stress protection. In many eukaryotic organisms, including yeast (Saccharomyces cerevisiae) and mammals, copper and iron homeostases are highly interconnected; yet, such interdependence is not well established in higher plants. Here, we propose that COPT2, a high-affinity copper transport protein, functions under copper and iron deficiencies in Arabidopsis (Arabidopsis thaliana). COPT2 is a plasma membrane protein that functions in copper acquisition and distribution. Characterization of the COPT2 expression pattern indicates a synergic response to copper and iron limitation in roots. We characterized a knockout of COPT2, copt2-1, that leads to increased resistance to simultaneous copper and iron deficiencies, measured as reduced leaf chlorosis and improved maintenance of the photosynthetic apparatus. We propose that COPT2 could play a dual role under iron deficiency. First, COPT2 participates in the attenuation of copper deficiency responses driven by iron limitation, possibly to minimize further iron consumption. Second, global expression analyses of copt2-1 versus wild-type Arabidopsis plants indicate that low-phosphate responses increase in the mutant. These results open up new biotechnological approaches to fight iron deficiency in crops. PMID:23487432

A comprehensive study on the damage tolerance of ultrafine-grained copper

PubMed Central

Hohenwarter, A.; Pippan, R.

2012-01-01

In this study the fracture behavior of ultrafine-grained copper was assessed by means of elasto-plastic fracture mechanics. For the synthesis of the material high pressure torsion was used. The fracture toughness was quantitatively measured by JIC as a global measure by recording the crack growth resistance curve. Additionally, the initiation toughness in terms of the crack opening displacement (CODi) was evaluated as a local fracture parameter. The results presented here exhibit a low fracture initiation toughness but simultaneously a remarkably high fracture toughness in terms of JIC. The origin of the large difference between these two parameters, peculiarities of the fracture surface and the fracture mechanical performance compared to coarse grained copper will be discussed. PMID:23471016

Technical Note: A novel interdigital transparent thin-film detector for medical dosimetry.

PubMed

Brivio, Davide; Sajo, Erno; Zygmanski, Piotr

2017-05-01

A new type of thin-film interdigital detector (TFID) for medical dosimetry is investigated. The focus of this study was to characterize the detector response as a function of detector geometry in an attempt to optimize it and to understand the underlying radio-electrical effects leading to signal formation. We characterize the detector response to kilovoltage x-ray beams used in fluoroscopy and computed tomography. Each element (pixel) of the detector is composed of conductive intercombing digits deposited on a thin-film dielectric substrate by nanofabrication or using a printing process. The detector is practically transparent to x-ray radiation, yet it generates sufficient signal for many types of medical dosimetry and quality assurance tasks. The thin-film detector has negligible surface mass density (about 2.5 mg/cm 2 for a 1-μm-thick Cu TFID on 12.5-μm-thick Kapton substrate) and it is conformable to curved geometries found in the medical x-ray equipment or on patient skin surface. The prototype detectors were made using glass and Kapton substrates with copper-copper and copper-aluminum interdigits. Although in principle the detector can be operated without any external bias voltage when the digits are made of disparate materials (e.g., Cu-Al), we also characterized the detector properties under small electric fields via its current-voltage curve (IV curve). Using 120 kVp, 25 mA x-ray beam with 10V external bias, the Cu-Cu detector response was about 0.2 nA/cm 2 . We also measured a one-dimensional transmitted dose profile for a phantom under fluoroscopic x-rays and found relatively good agreement with a commercial photodiode (XR R12-0191, IBA Dosimetry). We demonstrated the potential of TFID detectors for kilovoltage dosimetry and we defined its optimal geometry. For digits made of the same material and for digit width equal to the separation between them, we found that the thin-film detector has optimal performance when the distance between the digit centers is about 1 mm, while in the fixed digit width cases we observed that the signal is higher when their edge-to-edge separation is as small as possible. © 2017 American Association of Physicists in Medicine.

Effect of chloride ion concentration on the galvanic corrosion of α phase brass by eccrine sweat.

PubMed

Meekins, Andrew; Bond, John W; Chaloner, Penelope

2012-07-01

Inductively coupled plasma mass spectrometry measurement of the relative concentration of sodium, chloride, calcium, and potassium ions in eccrine sweat deposits from 40 donors revealed positive correlations between chloride and sodium (ρ = 0.684, p < 0.01) and chloride and calcium ions (ρ = 0.91, p < 0.01). Correlations between ion concentration and the corrosion of α phase brass by the donated sweat were investigated by visual grading of the degree of corrosion, by measuring the copper/zinc ratio using energy-dispersive X-ray spectroscopy, and from a measurement of the potential difference between corroded and uncorroded brass when a large potential was applied to the uncorroded brass. An increasing copper/zinc ratio (indicative of dezincification) was found to correlate positively to both chloride ion concentration and visual grading of corrosion, while visual grading gave correlations with potential difference measurements that were indicative of the preferential surface oxidation of zinc rather than copper. © 2012 American Academy of Forensic Sciences.

Multi-keV x-ray sources from metal-lined cylindrical hohlraums

NASA Astrophysics Data System (ADS)

Jacquet, L.; Girard, F.; Primout, M.; Villette, B.; Stemmler, Ph.

2012-08-01

As multi-keV x-ray sources, plastic hohlraums with inner walls coated with titanium, copper, and germanium have been fired on Omega in September 2009. For all the targets, the measured and calculated multi-keV x-ray power time histories are in a good qualitative agreement. In the same irradiation conditions, measured multi-keV x-ray conversion rates are ˜6%-8% for titanium, ˜2% for copper, and ˜0.5% for germanium. For titanium and copper hohlraums, the measured conversion rates are about two times higher than those given by hydroradiative computations. Conversely, for the germanium hohlraum, a rather good agreement is found between measured and computed conversion rates. To explain these findings, multi-keV integrated emissivities calculated with RADIOM [M. Busquet, Phys. Fluids 85, 4191 (1993)], the nonlocal-thermal-equilibrium atomic physics model used in our computations, have been compared to emissivities obtained from different other models. These comparisons provide an attractive way to explain the discrepancies between experimental and calculated quantitative results.

A new technique for online measurement of total and water-soluble copper (Cu) in coarse particulate matter (PM).

PubMed

Wang, Dongbin; Shafer, Martin M; Schauer, James J; Sioutas, Constantinos

2015-04-01

This study presents a novel system for online, field measurement of copper (Cu) in ambient coarse (2.5-10 μm) particulate matter (PM). This new system utilizes two virtual impactors combined with a modified liquid impinger (BioSampler) to collect coarse PM directly as concentrated slurry samples. The total and water-soluble Cu concentrations are subsequently measured by a copper Ion Selective Electrode (ISE). Laboratory evaluation results indicated excellent collection efficiency (over 85%) for particles in the coarse PM size ranges. In the field evaluations, very good agreements for both total and water-soluble Cu concentrations were obtained between online ISE-based monitor measurements and those analyzed by means of inductively coupled plasma mass spectrometry (ICP-MS). Moreover, the field tests indicated that the Cu monitor could achieve near-continuous operation for at least 6 consecutive days (a time resolution of 2-4 h) without obvious shortcomings. Copyright © 2015 Elsevier Ltd. All rights reserved.

How uncertain is model-based prediction of copper loads in stormwater runoff?

PubMed

Lindblom, E; Ahlman, S; Mikkelsen, P S

2007-01-01

In this paper, we conduct a systematic analysis of the uncertainty related with estimating the total load of pollution (copper) from a separate stormwater drainage system, conditioned on a specific combination of input data, a dynamic conceptual pollutant accumulation-washout model and measurements (runoff volumes and pollutant masses). We use the generalized likelihood uncertainty estimation (GLUE) methodology and generate posterior parameter distributions that result in model outputs encompassing a significant number of the highly variable measurements. Given the applied pollution accumulation-washout model and a total of 57 measurements during one month, the total predicted copper masses can be predicted within a range of +/-50% of the median value. The message is that this relatively large uncertainty should be acknowledged in connection with posting statements about micropollutant loads as estimated from dynamic models, even when calibrated with on-site concentration data.

Positron Annihilation and Complementary Studies of Copper Sandblasted with Alumina Particles at Different Pressures

PubMed Central

Horodek, Paweł; Dryzek, Jerzy; Wróbel, Mirosław

2017-01-01

Positron annihilation spectroscopy and complementary methods were used to detect changes induced by sandblasting of alumina particles at different pressures varying from 1 to 6 bar in pure well-annealed copper. The positron lifetime measurements revealed existence of dislocations and vacancy clusters in the adjoined surface layer. The presence of retained alumina particles in the copper at the depth below 50 µm was found in the SEM pictures and also in the annihilation line shape parameter profiles measured in the etching experiment. The profiles show us that the total depth of damaged zones induced by sandblasting of alumina particles ranges from 140 µm up to ca. 800 µm and it depends on the applied pressure. The work-hardening of the adjoined surface layer was found in the microhardness measurements at the cross-section of the sandblasted samples. PMID:29168749

Improvement of the radiographic method for measurement of effective energy of pulsed X-ray emission from a PF device for different anode's insert materials.

PubMed

Miremad, Seyed Milad; Shirani, Babak

2018-06-01

In this paper, effective energy of pulsed X-Ray emitted from a Mather-type plasma focus device in stored energy of 2.5 kJ with six different anode's insert materials was measured using radiographic method with attenuation filters. Since intensity and energy of X-ray beam were considerably changed with changing the insert material, the method was improved by using different filters simultaneously in all the experiments and selection of the best filter in each experiment according to the appropriate criteria. Effective energy of pulsed X-ray beam was measured 16, 28, 50, 51, 34 and 44 keV when aluminum, copper, zinc, tin, tungsten and lead were used as insert materials, and aluminum, copper, silver, silver, copper and lead were used as filters, respectively. Copyright © 2018 Elsevier Ltd. All rights reserved.

Effect of Ultrasonic on Copper Electroplating from the Non-Cyanide Alkaline Baths

NASA Astrophysics Data System (ADS)

Li, Minggang; Hu, Shuangshuang; Yang, Yejiong; Xu, Shuhan; Zhao, Xixi; Wei, Guoying

2014-06-01

Effects of the different ultrasonic powers on copper electrodeposition from non-cyanide alkaline baths by using pyrophosphate as complexing agent were investigated by different electrochemical methods. Cyclic voltammetry and current transient measurements were used to characterize the nucleation and growth mechanism. It is very obvious that the reduction potential moves to more positive one as the ultrasonic power increases. The quartz crystal microbalance (QCM) and chronoamperometric method were used to study the relationship between the mass change and the deposition time. It was found that the current efficiency of electrolyte under 0, 60, 80 and 100 W is 91.95%, 92.14%, 89.25% and 96.11%, respectively measured by QCM measurements. The surface morphology of the electrodeposited Cu films is analyzed by scanning electron microscopy (SEM). The morphology of copper films electrodeposited under the power of 60 W and 80 W presents a compact surface and the grains are fine and uniform.

Geomorphology and river dynamics of the lower Copper River, Alaska

USGS Publications Warehouse

Brabets, Timothy P.; Conaway, Jeffrey S.

2009-01-01

Located in south-central Alaska, the Copper River drains an area of more than 24,000 square miles. The average annual flow of the river near its mouth is 63,600 cubic feet per second, but is highly variable between winter and summer. In the winter, flow averages approximately 11,700 cubic feet per second, and in the summer, due to snowmelt, rainfall, and glacial melt, flow averages approximately 113,000 cubic feet per second, an order of magnitude higher. About 15 miles upstream of its mouth, the Copper River flows past the face of Childs Glacier and enters a large, broad, delta. The Copper River Highway traverses this flood plain, and in 2008, 11 bridges were located along this section of the highway. The bridges cross several parts of the Copper River and in recent years, the changing course of the river has seriously damaged some of the bridges.Analysis of aerial photography from 1991, 1996, 2002, 2006, and 2007 indicates the eastward migration of a channel of the Copper River that has resulted in damage to the Copper River Highway near Mile 43.5. Migration of another channel in the flood plain has resulted in damage to the approach of Bridge 339. As a verification of channel change, flow measurements were made at bridges along the Copper River Highway in 2005–07. Analysis of the flow measurements indicate that the total flow of the Copper River has shifted from approximately 50 percent passing through the bridges at Mile 27, near the western edge of the flood plain, and 50 percent passing through the bridges at Mile 36–37 to approximately 5 percent passing through the bridges at Mile 27 and 95 percent through the bridges at Mile 36–37 during average flow periods.The U.S. Geological Survey’s Multi-Dimensional Surface-Water Modeling System was used to simulate water-surface elevation and velocity, and to compute bed shear stress at two areas where the Copper River is affecting the Copper River Highway. After calibration, the model was used to examine the effects that betterments, such as guide banks or bridge extensions, would have on flow conditions and to provide sound conceptual information that could help decide if a proposed betterment will work or determine potential problems that need to be addressed for a particular betterment. The ability of the model to simulate these hydraulic conditions was constrained by the accuracy and level of channel geometry detail, which is constantly changing in the lower Copper River.

Role of drinking water copper in pathogenesis of oral submucous fibrosis: a prospective case control study.

PubMed

Arakeri, Gururaj; Hunasgi, Santosh; Colbert, Serryth; Merkx, M A W; Brennan, Peter A

2014-07-01

Although oral submucous fibrosis (OSMF) is thought to be multifactorial in origin, the chewing of areca nut is thought to be the main cause. Alkaloids and tannins in areca nut are responsible for fibrosis, but recent evidence has suggested that copper ions are also an important mediator, and in a small pilot study we recently found that OSMF was significantly associated with a raised concentration of copper in drinking water. We have further investigated this association in a heterogeneous population in Hyderabad-Karnataka, India, a region with a high incidence of the condition. We evaluated 3 groups, each of 100 patients: those with OSMF who chewed gutkha, those who chewed gutkha but did not have OSMF, and healthy controls who did not chew gutkha. The difference between the groups in the mean concentration of copper in water measured by atomic absorption spectrometry was significant (p<0.001). There were also significant differences between the groups in mean concentrations of serum copper, salivary copper, and ceruloplasmin (p<0.001). Our results confirm that copper in drinking water contributes to the pathogenesis of OSMF, but ingestion of copper is unlikely to be the sole cause. Copyright © 2014 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Supplementation with zinc in rats enhances memory and reverses an age-dependent increase in plasma copper.

PubMed

Sandusky-Beltran, Leslie A; Manchester, Bryce L; McNay, Ewan C

2017-08-30

Zinc and copper are essential trace elements. Dyshomeostasis in these two metals has been observed in Alzheimer's disease, which causes profound cognitive impairment. Insulin therapy has been shown to enhance cognitive performance; however, recent data suggest that this effect may be at least in part due to the inclusion of zinc in the insulin formulation used. Zinc plays a key role in regulation of neuronal glutamate signaling, suggesting a possible link between zinc and memory processes. Consistent with this, zinc deficiency causes cognitive impairments in children. The effect of zinc supplementation on short- and long-term recognition memory, and on spatial working memory, was explored in young and adult male Sprague Dawley rats. After behavioral testing, hippocampal and plasma zinc and copper were measured. Age increased hippocampal zinc and copper, as well as plasma copper, and decreased plasma zinc. An interaction between age and treatment affecting plasma copper was also found, with zinc supplementation reversing elevated plasma copper concentration in adult rats. Zinc supplementation enhanced cognitive performance across tasks. These data support zinc as a plausible therapeutic intervention to ameliorate cognitive impairment in disorders characterized by alterations in zinc and copper, such as Alzheimer's disease. Copyright © 2017 Elsevier B.V. All rights reserved.

Measured density of copper atoms in the ground and metastable states in argon magnetron discharge correlated with the deposition rate

NASA Astrophysics Data System (ADS)

Naghshara, H.; Sobhanian, S.; Khorram, S.; Sadeghi, N.

2011-01-01

In a dc-magnetron discharge with argon feed gas, densities of copper atoms in the ground state Cu(2S1/2) and metastable state Cu*(2D5/2) were measured by the resonance absorption technique, using a commercial hollow cathode lamp as light source. The operating conditions were 0.3-14 µbar argon pressure and 10-200 W magnetron discharge power. The deposition rate of copper in a substrate positioned at 18 cm from the target was also measured with a quartz microbalance. The gas temperature, in the range 300-380 K, was deduced from the emission spectral profile of N2(C 3Πu - B 3Πg) 0-0 band at 337 nm when trace of nitrogen was added to the argon feed gas. The isotope-shifts and hyperfine structures of electronic states of Cu have been taken into account to deduce the emission and absorption line profiles, and hence for the determination of atoms' densities from the measured absorption rates. To prevent error in the evaluation of Cu density, attributed to the line profile distortion by auto-absorption inside the lamp, the lamp current was limited to 5 mA. Density of Cu(2S1/2) atoms and deposition rate both increased with the enhanced magnetron discharge power. But at fixed power, the copper density augmented with argon pressure whereas the deposition rate followed the opposite trend. Whatever the gas pressure, the density of Cu*(2D5/2) metastable atoms remained below the detection limit of 1 × 1010 cm-3 for magnetron discharge powers below 50 W and hence increased much more rapidly than the density of Cu(2S1/2) atoms, over passing this later at some discharge power, whose value decreases with increasing argon pressure. This behaviour is believed to result from the enhancement of plasma density with increasing discharge power and argon pressure, which would increase the excitation rate of copper into metastable states. At fixed pressure, the deposition rate followed the same trend as the total density of copper atoms in the ground and metastable states. Two important conclusions of this work are (i) copper atoms sputtered from the target under ion bombardment are almost all in the ground state Cu(2S1/2) and hence in the plasma volume they can be excited into the metastable states; (ii) all atoms in the long-lived ground and metastable states contribute to the deposition of copper layer on the substrate.

Characteristics and antimicrobial activity of copper-based materials

NASA Astrophysics Data System (ADS)

Li, Bowen

In this study, copper vermiculite was synthesized, and the characteristics, antimicrobial effects, and chemical stability of copper vermiculite were investigated. Two types of copper vermiculite materials, micron-sized copper vermiculite (MCV) and exfoliated copper vermiculite (MECV), are selected for this research. Since most of the functional fillers used in industry products, such as plastics, paints, rubbers, papers, and textiles prefer micron-scaled particles, micron-sized copper vermiculite was prepared by jet-milling vermiculite. Meanwhile, since the exfoliated vermiculite has very unique properties, such as high porosity, specific surface area, high aspect ratio of laminates, and low density, and has been extensively utilized as a functional additives, exfoliated copper vermiculite also was synthesized and investigated. The antibacterial efficiency of copper vermiculite was qualitatively evaluated by the diffusion methods (both liquid diffusion and solid diffusion) against the most common pathogenic species: Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Klebsiella pneumoniae (K. pneumoniae). The result showed that the release velocity of copper from copper vermiculite is very slow. However, copper vermiculite clearly has excellent antibacterial efficiency to S. aureus, K. pneumoniae and E. coli. The strongest antibacterial ability of copper vermiculite is its action on S. aureus. The antibacterial efficiency of copper vermiculite was also quantitatively evaluated by determining the reduction rate (death rate) of E. coli versus various levels of copper vermiculite. 10 ppm of copper vermiculite in solution is sufficient to reduce the cell population of E. coli, while the untreated vermiculite had no antibacterial activity. The slow release of copper revealed that the antimicrobial effect of copper vermiculite was due to the strong interactions between copper ions and bacteria cells. Exfoliated copper vermiculite has even stronger antibacterial activity than copper vermiculite against E. coli. With 200 ppm exfoliated copper vermiculite in bacteria suspension (4.68 ppm of metal copper), the reduction of viable bacteria are 99.8% at 1 hour, and >99.9% at 2 hours. With 10 ppm exfoliated copper vermiculite in bacteria dilution (0.234 ppm of copper atoms), the reduction of viable E. coli reached 98.7% at 1 hour, and >95.6% at 2 hours. Molds have the potential to cause health problems, such as allergic reactions, irritations, and mycotoxins, and damage to buildings, historic relics, properties, etc. Since copper has better antifungal property, an initial antifungal activity of copper vermiculite was evaluated in this study. Fat-free milk was used to develop molds in the test samples by saturated samples. Incubated at 36°C for 48 hours, all of the surfaces of untreated control samples, including micron-sized vermiculite, exfoliated vermiculite, bentonite, and kaolin, have been covered by thick mold layers. However, there were no mold showed on copper vermiculite and exfoliated copper vermiculite. Even after the incubation was lasted for 10 days, copper vermiculite and exfoliated copper vermiculite did not show any mold on the surface. These results exhibited copper vermiculite has excellent antifungal activities against mold. Stability of copper ions in copper vermiculite was measured by aqueous leaching process. Copper vermiculite and exfoliated copper vermiculite were put into distilled water in a ratio of 2.0g/100ml, and then implemented leaching processes by continuously shaking (leaching) and statically storing (soaking) for desired periods of time, respectively. According to the analytic result by inductively coupled plasma spectroscopy (ICP), the major metals released were copper, magnesium, iron, silicon, and aluminum. The release rate of copper depends on the environmental conditions. Under the dynamic leaching condition, all the major elements had shown linear leaching rates, and slowly increases along with the leaching time. Copper concentration in 1 hour leached solutions had sufficient concentration to inhibit E. coli in aqueous solution. Lasting for 1 month, 1 gram of copper vermiculite only released 185mug of copper. At this velocity, 11.5 years are required to completely exhaust the copper atoms from copper vermiculite. A soaking process provided a lower release rate than leaching process. Comparably, exfoliated copper vermiculite had lower copper concentration, stronger antimicrobial effect, but faster release rate than copper vermiculite, due to their different structure characteristics. (Abstract shortened by UMI.)

Differentiation and Exploration of Model MACP for HE VER 1.0 on Prototype Performance Measurement Application for Higher Education

NASA Astrophysics Data System (ADS)

El Akbar, R. Reza; Anshary, Muhammad Adi Khairul; Hariadi, Dennis

2018-02-01

Model MACP for HE ver.1. Is a model that describes how to perform measurement and monitoring performance for Higher Education. Based on a review of the research related to the model, there are several parts of the model component to develop in further research, so this research has four main objectives. The first objective is to differentiate the CSF (critical success factor) components in the previous model, the two key KPI (key performance indicators) exploration in the previous model, the three based on the previous objective, the new and more detailed model design. The final goal is the fourth designed prototype application for performance measurement in higher education, based on a new model created. The method used is explorative research method and application design using prototype method. The results of this study are first, forming a more detailed new model for measurement and monitoring of performance in higher education, differentiation and exploration of the Model MACP for HE Ver.1. The second result compiles a dictionary of college performance measurement by re-evaluating the existing indicators. The third result is the design of prototype application of performance measurement in higher education.

SiPM application for a detector for UHE neutrinos tested at Sphinx station

NASA Astrophysics Data System (ADS)

Iori, M.; Atakisi, I. O.; Chiodi, G.; Denizli, H.; Ferrarotto, F.; Kaya, M.; Yilmaz, A.; Recchia, L.; Russ, J.

2014-04-01

We present the preliminary test results of the prototype detector, working at Sphinx Observatory Center, Jungfraujoch (~3800 m a.s.l.) HFSJG - Switzerland. This prototype detector is designed to measure large zenith angle showers produced by high energy neutrino interactions in the Earth crust. This station provides us an opportunity to understand if the prototype detector works safely (or not) under hard environmental conditions (the air temperature changes between -25 °C and -5 °C). The detector prototype is using silicon photomultiplier (SiPM) produced by SensL and DRS4 chip as read-out part. Measurements at different temperature at fixed bias voltage (~29.5 V) were performed to reconstruct tracks by Time Of Flight.

Growth response, blood characteristics and copper accumulation in organs of broilers fed on diets supplemented with organic and inorganic dietary copper sources.

PubMed

Jegede, A V; Oduguwa, O O; Bamgbose, A M; Fanimo, A O; Nollet, L

2011-02-01

1. A 56-d experiment was conducted to study the comparative influence of organic and inorganic dietary copper (Cu) sources on growth, blood characteristics and copper accumulation in organs of broilers. 2. A total of 480 Arbor-Acre unsexed broilers were fed on diets containing copper sulphate (CuSO(4)) or copper proteinate (Cu Pro) at concentrations of 50, 100 or 150 mg/kg of Cu supplementation. The birds were given a broiler starter diet from 1-28 d and a broiler finisher diet from 29-56 d which contained 30·8 mg/kg and 41·1 mg/kg basal copper concentration respectively. Growth performance, blood characteristics and Cu accumulation in organs of the broilers were measured. 3. At 28 d, Cu Pro-fed birds had improved feed conversion ratio compared with CuSO(4). At 56 d, birds fed on Cu Pro diets had significantly greater body weight than CuSO(4)-fed birds. Birds fed on CuSO(4) supplemented diets had significantly better feed conversion efficiency. Feed consumptions for the two Cu sources were not significantly different. At no stage did the concentration of added Cu affect the productive traits measured. 4. Cu Pro supplementation increased haemoglobin concentration but reduced plasma triglyceride and plasma cholesterol. Plasma cholesterol decreased as Cu concentration increased. 5. There was a greater accumulation of Cu in the blood, heart, lung, liver and bone of broilers fed on Cu Pro than in those receiving CuSO(4). The liver Cu concentration increased as dietary Cu concentration increased. 6. Cu Pro was more effective in promoting growth and reducing blood cholesterol, and was more bio-available in the organs of broilers.

Reduction of health care-associated infection indicators by copper oxide-impregnated textiles: Crossover, double-blind controlled study in chronic ventilator-dependent patients.

PubMed

Marcus, Esther-Lee; Yosef, Hana; Borkow, Gadi; Caine, Yehezkel; Sasson, Ady; Moses, Allon E

2017-04-01

Copper oxide has potent wide-spectrum biocidal properties. The purpose of this study is to determine if replacing hospital textiles with copper oxide-impregnated textiles reduces the following health care-associated infection (HAI) indicators: antibiotic treatment initiation events (ATIEs), fever days, and antibiotic usage in hospitalized chronic ventilator-dependent patients. A 7-month, crossover, double-blind controlled trial including all patients in 2 ventilator-dependent wards in a long-term care hospital. For 3 months (period 1), one ward received copper oxide-impregnated textiles and the other received untreated textiles. After a 1-month washout period of using regular textiles, for 3 months (period 2) the ward that received the treated textiles received the control textiles and vice versa. The personnel were blinded to which were treated or control textiles. There were no differences in infection control measures during the study. There were reductions of 29.3% (P = .002), 55.5% (P < .0001), 23.0% (P < .0001), and 27.5% (P < .0001) in the ATIEs, fever days (>37.6°C), days of antibiotic treatment, and antibiotic defined daily dose per 1,000 hospitalization days, respectively, when using the copper oxide-impregnated textiles. Use of copper oxide-impregnated biocidal textiles in a long-term care ward of ventilator-dependent patients was associated with a significant reduction of HAI indicators and antibiotic utilization. Using copper oxide-impregnated biocidal textiles may be an important measure aimed at reducing HAIs in long-term care medical settings. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

Biotransference and biomagnification of selenium copper, cadmium, zinc, arsenic and lead in a temperate seagrass ecosystem from Lake Macquarie Estuary, NSW, Australia.

PubMed

Barwick, M; Maher, W

2003-10-01

In this study the biotransference of selenium copper, cadmium, zinc, arsenic and lead was measured in a contaminated seagrass ecosystem in Lake Macquarie, NSW, Australia, to determine if biomagnification of these trace metals is occurring and if they reach concentrations that pose a threat to the resident organisms or human consumers. Selenium was found to biomagnify, exceeding maximum permitted concentrations for human consumption within carnivorous fish tissue, the highest trophic level examined. Selenium concentrations measured within carnivorous fish were also above those shown to elicit sub-lethal effects in freshwater fish. As comparisons are made to selenium concentrations known to effect freshwater fish, inferences must be made with caution. There was no evidence of copper, cadmium, zinc or lead biomagnification within the food web examined. Copper, cadmium, zinc and lead concentrations were below concentrations shown to elicit adverse responses in biota. Copper concentrations within crustaceans M. bennettae and P. palagicus were found to exceed maximum permitted concentrations for human consumption. It is likely that copper concentrations within these species were accumulated due to the essential nature of this trace metal for many species of molluscs and crustaceans. Arsenic showed some evidence of biomagnification. Total arsenic concentrations are similar to those found in other uncontaminated marine ecosystems, thus arsenic concentrations are unlikely to cause adverse effects to aquatic organisms. Inorganic arsenic concentrations are below maximum permitted concentrations for human consumption.

Influence of CuSO4 and chelated copper algaecide exposures on biodegradation of microcystin-LR.

PubMed

Iwinski, Kyla J; Rodgers, John H; Kinley, Ciera M; Hendrikse, Maas; Calomeni, Alyssa J; McQueen, Andrew D; Geer, Tyler D; Liang, Jenny; Friesen, Vanessa; Haakensen, Monique

2017-05-01

Copper exposures from algaecide applications in aquatic systems are hypothesized to impede bacterial degradation of microcystin (MC), a cyanobacterial produced hepatotoxin. Despite regulatory implications of this hypothesis, limited data exist on influences of copper-exposures on MC-degrading bacteria and consequent MC-degradation. In this study, influences of copper-algaecide concentrations and formulations on bacterial composition and microcystin-LR (MCLR) degradation were investigated. Microcystis aeruginosa was exposed to four concentrations (0-5.0 mg Cu L -1 ) of three copper-algaecide formulations, and rates and extents of MCLR degradation were measured. In untreated controls and following exposures of 0.1, 0.5, and 1.0 mg Cu L -1 , MCLR concentrations decreased at a rate of ∼41-53 μg MCLR/L d -1 . Following exposure to 5.0 mg Cu L -1 MCLR degradation rates decreased an order of magnitude to ∼3-7 μg MCLR/L d -1 . Bacterial diversity decreased following copper-exposures greater than 0.1 mg Cu L -1 for all formulations. Relative abundance of certain groups of MC-degrading bacteria identified in treatments increased with increasing copper concentration, suggesting they may be less sensitive to copper exposures than other, MCLR and non MC-degrading heterotrophic bacteria present in the assemblage. Results from this study revealed that copper concentration can influence degradation rates of MCLR, however this influence was not significant within copper concentrations currently registered for use (≤1.0 mg Cu L -1 ) of the tested algaecides. Copper formulation did not significantly alter degradation rates or bacterial composition. These data augment our understanding of the influences of copper algaecide-exposures on MCLR degradation, and can be used to inform more accurate risk evaluations and use of copper-algaecides for management of MCLR-producing cyanobacteria. Copyright © 2017 Elsevier Ltd. All rights reserved.

Investigating the role of implicit prototypes in the prototype willingness model.

PubMed

Howell, Jennifer L; Ratliff, Kate A

2017-06-01

One useful theory to predict health behavior is the prototype-willingness model (PWM), which posits that people are more willing to engage in behavior to the extent that they have a positive view of the prototypical person who performs that behavior. The goal of the present research is to test whether adding an implicit measure of prototype favorability might improve explanatory power in the PWM. Two studies examined whether implicit prototype favorability uniquely predicted White women's intentions to engage in healthy sun behavior over the next 3-6 months, and their willingness to engage in risky sun behavior, should the opportunity arise. The results suggested that implicit prototype favorability, particularly implicit prototypes of those who engage in risky UV-related behaviors, uniquely predicted intentions to engage in healthy sun behavior and willingness to engage in risky sun behavior in the PWM.

The influence of duckweed species diversity on ecophysiological tolerance to copper exposure.

PubMed

Zhao, Zhao; Shi, Huijuan; Duan, Dongzhu; Li, Hongmei; Lei, Tingwen; Wang, Maolin; Zhao, Hai; Zhao, Yun

2015-07-01

In excess, copper is toxic to plants. In the plants, Landoltia punctata and Lemna minor grown in mixed and monoculture, the effects of exposure to varying concentrations of copper (0.01, 0.1, 0.5 and 1mgL(-1) Cu) for seven days were assessed by measuring changes in the chlorophyll, protein and malondialdehyde (MDA) content, catalase (CAT), superoxide dismutase (SOD) and ascorbate peroxidase (APX) activity. According to results, Cu levels in plants increased with increasing Cu concentration. The level of photosynthetic pigments and crude proteins decreased only upon exposure to high Cu concentrations. However, the starch and malondialdehyde (MDA) content increased. These results suggested a stress alleviation that was possibly the result of antioxidants such as CAT and SOD, the activities of which increased with increasing Cu levels. APX activity increased in L. punctata, but decreased in L. minor, under monoculture or mixed culture conditions. In addition, the duckweed in mixed culture exhibited increased antioxidant enzyme activities which provide increased resistance to copper in moderate copper concentrations. As the copper concentration increased, the duckweed in the mixed culture limited the uptake of copper to avoid toxicity. Copyright © 2015 Elsevier B.V. All rights reserved.

Polystyrene films as barrier layers for corrosion protection of copper and copper alloys.

PubMed

Románszki, Loránd; Datsenko, Iaryna; May, Zoltán; Telegdi, Judit; Nyikos, Lajos; Sand, Wolfgang

2014-06-01

Dip-coated polystyrene layers of sub-micrometre thickness (85-500nm) have been applied on copper and copper alloys (aluminium brass, copper-nickel 70/30), as well as on stainless steel 304, and produced an effective barrier against corrosion and adhesion of corrosion-relevant microorganisms. According to the dynamic wettability measurements, the coatings exhibited high advancing (103°), receding (79°) and equilibrium (87°) contact angles, low contact angle hysteresis (6°) and surface free energy (31mJ/m(2)). The corrosion rate of copper-nickel 70/30 alloy samples in 3.5% NaCl was as low as 3.2μm/a (44% of that of the uncoated samples), and in artificial seawater was only 0.9μm/a (29% of that of the uncoated samples). Cell adhesion was studied by fluorescence microscopy, using monoculture of Desulfovibrio alaskensis. The coatings not only decreased the corrosion rate but also markedly reduced the number of bacterial cells adhered to the coated surfaces. The PS coating on copper gave the best result, 2×10(3)cells/cm(2) (1% of that of the uncoated control). © 2013 Elsevier B.V. All rights reserved.

Copper-Based Aquatic Algaecide Adsorption and Accumulation Kinetics: Influence of Exposure Concentration and Duration for Controlling the Cyanobacterium Lyngbya wollei.

PubMed

Bishop, West M; Lynch, Clayton L; Willis, Ben E; Cope, W Gregory

2017-09-01

Filamentous mat-forming cyanobacteria are increasingly impairing uses of freshwater resources. To effectively manage, a better understanding of control measures is needed. Copper (Cu)-based algaecide formulations are often applied to reactively control nuisance cyanobacterial blooms. This laboratory research assessed typical field exposure scenarios for the ability of Cu to partition to, and accumulate in Lyngbya wollei. Exposure factors (Cu concentration × duration) of 4, 8, 16, 24, 32 h were tested across three aqueous Cu concentrations (1, 2, 4 ppm). Results indicated that internally accumulated copper correlated with control of L. wollei, independent of adsorbed copper. L. wollei control was determined by filament viability and chlorophyll a concentrations. Similar exposure factors elicited similar internalized copper levels and consequent responses of L. wollei. Ultimately, a "concentration-exposure-time" (CET) model was created to assist water resource managers in selecting an appropriate treatment regime for a specific in-water infestation. By assessing the exposure concentration and duration required to achieve the internal threshold of copper (i.e., critical burden) that elicits control, water management objectives can be achieved while simultaneously decreasing the environmental loading of copper and potential for non-target species risks.

Preparation of Semiconducting Materials in the Laboratory, Part 3: The One-Penny Photovoltaic Cell

ERIC Educational Resources Information Center

Ibanez, Jorge G.; Finck-Pastrana, Adolfo; Mugica-Barrera, Alejandra; Balderas-Hernandez, Patricia; Ibarguengoitia-Cervantes, Martha E.; Garcia-Pintor, Elizabeth; Hartasanchez-Frenk, Jose Miguel; Bonilla-Jaurez, Cesar E.; Maldonado-Cordero, Casandra; Struck-Garza, Adelwart; Suberbie-Rocha, Felipe

2011-01-01

Copper(I) oxide photoresponsive layers are prepared on copper surfaces (e.g., U.S. pre-1982 pennies) by simple thermal, chemical, and electrochemical procedures. An easily measurable photovoltage (up to 100 mV) is obtained in each case under visible light illumination. (Contains 2 figures.)

Some Characteristics of Free Cell Population in the Airways of Rats after Intratracheal Instillation of Copper-Containing Nano-Scale Particles

PubMed Central

Privalova, Larisa I.; Katsnelson, Boris A.; Loginova, Nadezhda V.; Gurvich, Vladimir B.; Shur, Vladimir Y.; Beikin, Yakov B.; Sutunkova, Marina P.; Minigalieva, Ilzira A.; Shishkina, Ekaterina V.; Pichugova, Svetlana V.; Tulakina, Ludmila G.; Beljayeva, Svetlana V.

2014-01-01

We used stable water suspensions of copper oxide particles with mean diameter 20 nm and of particles containing copper oxide and element copper with mean diameter 340 nm to assess the pulmonary phagocytosis response of rats to a single intratracheal instillation of these suspensions using optical, transmission electron, and semi-contact atomic force microscopy and biochemical indices measured in the bronchoalveolar lavage fluid. Although both nano and submicron ultrafine particles were adversely bioactive, the former were found to be more toxic for lungs as compared with the latter while evoking more pronounced defense recruitment of alveolar macrophages and especially of neutrophil leukocytes and more active phagocytosis. Based on our results and literature data, we consider both copper solubilization and direct contact with cellular organelles (mainly, mitochondria) of persistent particles internalized by phagocytes as probable mechanisms of their cytotoxicity. PMID:25421246

Novel metal based anti-tuberculosis agent: synthesis, characterization, catalytic and pharmacological activities of copper complexes.

PubMed

Joseph, J; Nagashri, K; Janaki, G Boomadevi

2012-03-01

Copper complexes of molecular formulae, [CuL(1)(OAc)], [CuL(2)(H(2)O)], [CuL(3)(H(2)O)], [CuL(4)(H(2)O)], [CuL(5)(H(2)O)] where L(1)-L(5) represents Schiff base ligands [by the condensation of 3-hydroxyflavone with 4-aminoantipyrine (L(1))/o-aminophenol (L(2))/o-aminobenzoic acid (L(3))/o-aminothiazole (L(4))/thiosemicarbazide (L(5))], have been prepared. They were characterized using analytical and spectral techniques. The DNA binding properties of copper complexes were studied using electronic absorption spectra and viscosity measurements. Superoxide dismutase and antioxidant activities of the copper complexes have also been studied. Furthermore, the copper complexes have been found to promote pUC18 DNA cleavage in the presence of oxidant. Anti-tuberculosis activity was also performed. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

Engineering and Design of the Steady Inductive Helicity Injected Torus (HIT--SI)

NASA Astrophysics Data System (ADS)

Sieck, P. E.; Jarboe, T. R.; Nelson, B. A.; Rogers, J. A.; Shumlak, U.

1999-11-01

Steady Inductive Helicity Injection (SIHI) is an inductive helicity injection method that injects helicity at a nearly constant rate, without open field lines, and without removing any helicity or magnetic energy from the plasma.(T.R. Jarboe, Fusion Technology, 36) (1), p. 85, 1999 SIHI directly produces a rotating magnetic field structure, and in the frame of the rotating field the current profile is nearly time independent. The Steady Inductive Helicity Injected Torus (HIT--SI) is a spheromak designed to implement SIHI so that the current profile in the rotating frame is optimized. The geometry of HIT--SI will be presented, including the manufacturing techniques and metallurgical processes planned for construction of the close-fitting flux conserver. The flux conserver is made of aged chromium copper with 80% the conductivity of pure copper. The detailed electrical insulation requirements in the helicity injector design lead to a complex o-ring seal and a plasma-sprayed alumina insulation coating. This has prompted the construction of an o-ring prototype test fixture having the main features of the o-ring design and the alumina coating. The design and evaluation of this fixture will also be presented with vacuum and voltage test results.

Water Based Phase Change Material Heat Exchanger Development

NASA Technical Reports Server (NTRS)

Hansen, Scott W.; Sheth, Ribik B.; Atwell, Matt; Cheek, Ann; Agarwal, Muskan; Hong, Steven; Patel, Aashini,; Nguyen, Lisa; Posada, Luciano

2014-01-01

In a cyclical heat load environment such as low Lunar orbit, a spacecraft’s radiators are not sized to reject the full heat load requirement. Traditionally, a supplemental heat rejection device (SHReD) such as an evaporator or sublimator is used to act as a “topper” to meet the additional heat rejection demands. Utilizing a Phase Change Material (PCM) heat exchanger (HX) as a SHReD provides an attractive alternative to evaporators and sublimators as PCM HXs do not use a consumable, thereby leading to reduced launch mass and volume requirements. Studies conducted in this paper investigate utilizing water’s high latent heat of formation as a PCM, as opposed to traditional waxes, and corresponding complications surrounding freezing water in an enclosed volume. Work highlighted in this study is primarily visual and includes understanding ice formation, freeze front propagation, and the solidification process of water/ice. Various test coupons were constructed of copper to emulate the interstitial pin configuration (to aid in conduction) of the proposed water PCM HX design. Construction of a prototypic HX was also completed in which a flexible bladder material and interstitial pin configurations were tested. Additionally, a microgravity flight was conducted where three copper test articles were frozen continuously during microgravity and 2-g periods and individual water droplets were frozen during microgravity.

Effect of copper on Mytilus californianus and Mytilus edulis. Annual report

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

Not Available

1980-06-06

Mytilus edulis and Mytilus californianus have come into widespread use as valuable test animals in estimating the effects and extent of copper pollution, both naturally as indicators and under simulated conditions as bioassays. These mussels are known bioaccumulators of heavy metals. They have a broad distribution, and mutually exclusive habitats. How the mussel reacts to copper is directly related to how copper affects the physiology of the mussel. The filtration rate and oxygen consumption of Mytilus are known to decline by more than 50% under exposure to as low as 200 ppB Cu in the water. Decline in heart ratemore » (bradycardia) also occurs under exposure to copper. Byssus thread production suffers in copper concentrations of 500 ppB and higher. The ability of M. edulis to close its valves in the presence of copper has been documented by several researchers. Of all the physiological parameters, oxygen consumption, heart rate, and valve closure are basic physiological functions which are easily measured. Mortality of Mytilus edulis is known to occur at concentrations of copper 330 ppB and higher within four to five days. It would be advantageous to have a continuous monitoring of the heart, oxygen consumption, and valve gape during this period to determine the state of each and the contribution of each to the possible death of the mussel. This study involves monitoring the three above physiological functions under varying concentrations of copper. In both species, M. edulis and M. californianus, detailed toxicological response records were obtained for each function. These records were then used to compare the physiological responses of each species to different levels of ambient copper in order to explain the possibility of repeatable, species-specific, response patterns to copper. (ERB)« less

Inheritable copper tolerance in the chlorophyte macroalga Enteromorpha intestinalis

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

Lewis, S.; Williams, P.; Donkin, M.

1995-12-31

A study was carried out to determine if a population of Enteromorpha intestinalis, from a metal polluted site, exhibited copper tolerance. This work was in preparation for investigating stress protein patterns in copper tolerant and sensitive populations. The effects of copper on growth of E. intestinalis from three clean and one metal polluted site were compared. Growth was assessed by incubating thallus sections in a range of copper solutions and measuring increase in length. Offspring were cultured from clean and polluted sites and the effects of copper on their growth assessed, to determine if any tolerance was inheritable. Concentrations ofmore » the trace metals; copper, zinc and manganese in the populations were also determined. Over the range of copper concentrations tested (0--150 {micro}g/i), growth of the polluted site populations was not significantly affected (P > 0.05). However growth of the clean site populations was significantly depressed by exposure to 50 {micro}g/l. This pattern of response was also exhibited by the offspring. Trace metal concentrations in the clean site populations were very similar, however the polluted site population contained {sup {minus}}10 times the control site values of manganese and {approximately}35 times the values of zinc and copper. The results suggest that the polluted site population of E. intestinalis has developed a degree of copper tolerance which appears to have a genetic basis. This investigation is consistent with previous work into copper tolerance in ship-fouling populations of E. intestinalis var. compressa. A commercially available HSP70 antibody with a high degree of cross-reactivity to E. intestinalis has been identified and used to screen samples of the seaweed from the aforementioned populations.« less

A Cooperative Copper Metal-Organic Framework-Hydrogel System Improves Wound Healing in Diabetes.

PubMed

Xiao, Jisheng; Chen, Siyu; Yi, Ji; Zhang, Hao; Ameer, Guillermo A

2017-01-05

Chronic non-healing wounds remain a major clinical challenge that would benefit from the development of advanced, regenerative dressings that promote wound closure within a clinically relevant time frame. The use of copper ions has shown promise in wound healing applications possibly by promoting angiogenesis. However, reported treatments that use copper ions require multiple applications of copper salts or oxides to the wound bed, exposing the patient to potentially toxic levels of copper ions and resulting in variable outcomes. Herein we set out to assess whether copper metal organic framework nanoparticles (HKUST-1 NPs) embedded within an antioxidant thermoresponsive citrate-based hydrogel would decrease copper ion toxicity and accelerate wound healing in diabetic mice. HKUST-1 and poly-(polyethyleneglycol citrate-co- N -isopropylacrylamide) (PPCN) were synthesized and characterized. HKUST-1 NP stability in a protein solution with and without embedding them in PPCN hydrogel was determined. Copper ion release, cytotoxicity, apoptosis, and in vitro migration processes were measured. Wound closure rates and wound blood perfusion were assessed in vivo using the splinted excisional dermal wound diabetic mouse model. HKUST-1 NP disintegrated in protein solution while HKUST-1 NPs embedded in PPCN (H-HKUST-1) were protected from degradation and copper ions were slowly released. Cytotoxicity and apoptosis due to copper ion release were significantly reduced while dermal cell migration in vitro and wound closure rates in vivo were significantly enhanced. In vivo , H-HKUST-1 induced angiogenesis, collagen deposition, and re-epithelialization during wound healing in diabetic mice. These results suggest that a cooperatively stabilized, copper ion-releasing H-HKUST-1 hydrogel is a promising innovative dressing for the treatment of chronic wounds.

Wideband characterization of printed circuit board materials up to 50 ghz

NASA Astrophysics Data System (ADS)

Rakov, Aleksei

A traveling-wave technique developed a few years ago in the Missouri S&T EMC Laboratory has been employed until now for characterization of PCB materials over a broad frequency range up to 30 GHz. This technique includes measuring S-parameters of the specially designed PCB test vehicles. An extension of the frequency range of printed circuit board laminate dielectric and copper foil characterization is an important problem. In this work, a new PCB test vehicle design for operating up to 50 GHz has been proposed. As the frequency range of measurements increases, the analysis of errors and uncertainties in measuring dielectric properties becomes increasingly important. Formulas for quantification of two major groups of errors, repeatability (manufacturing variability) and reproducibility (systematic) errors, in extracting dielectric constant (DK) and dissipation factor (DK) have been derived, and computations for a number of cases are presented. Conductor (copper foil) surface roughness of PCB interconnects is an important factor, which affects accuracy of DK and DF measurements. This work describes a new algorithm for semi-automatic characterization of copper foil profiles on optical or scanning electron microscopy (SEM) pictures of signal traces. The collected statistics of numerous copper foil roughness profiles allows for introducing a new metric for roughness characterization of PCB interconnects. This is an important step to refining the measured DK and DF parameters from roughness contributions. The collected foil profile data and its analysis allow for developing "design curves", which could be used by SI engineers and electronics developers in their designs.

Evaluated activation cross sections of longer-lived radionuclides produced by deuteron-induced reactions on natural copper

NASA Astrophysics Data System (ADS)

Takács, S.; Tárkányi, F.; Király, B.; Hermanne, A.; Sonck, M.

2006-09-01

Activation cross sections for deuteron-induced reactions on natural copper were measured by using a standard stacked foil technique up to 50 MeV deuteron bombarding energy. Reaction products with half-life longer than half an hour were studied. Experimental elemental cross sections were determined and compared with earlier measured data for 62,63,65Zn, 64Cu, 57,65Ni, 57,58,60Co and 59Fe isotopes.

Evaluation of copper toxicity using site specific algae and water chemistry: Field validation of laboratory bioassays.

PubMed

Fawaz, Elyssa G; Salam, Darine A; Kamareddine, Lina

2018-07-15

Studies of metal toxicity to microalgae have predominantly been conducted using single non-target algae species and without due regard for the chemistry of the treated waters, leading to ineffective or excessive algaecide treatments. In this study, indigenous multi-algal species (Scenedesmus quadricauda, and Scenedesmus subspicatus and Oscillatoria agardhii) were used in laboratory toxicity bioassays under simulated field water chemistry (pH = 7.2, hardness = 196 mg L -1 as CaCO 3 , and alkalinity = 222 mg L -1 as CaCO 3 ) to determine the optimum copper sulfate treatment dose to control algae growth in an irrigation canal. Toxicity bioassays were conducted using copper sulfate in chelated (with EDTA) and non-chelated (without EDTA) forms to assess the influence of the use of synthetic chelators in toxicity studies. Also, copper toxicity to the indigenous algae species was measured in the non-modified EPA test medium (pH = 7.5, hardness = 92 mg L -1 as CaCO 3 , alkalinity = 10 mg L -1 as CaCO 3 and EDTA= 300 µg L -1 ) to assess the impact of the water chemistry on algae inhibitory algal dosages. Under simulated water chemistry conditions, lower toxicity was measured in the test flasks with the chelated form of copper (96 h- EC 50 = 386.67 µg L -1 as Cu) as compared to those with the non-chelated metal (96 h-EC 50 = 217.17 µg L -1 as Cu). In addition, higher copper toxicity was measured in the test flasks prepared with the non-modified EPA medium using chelated copper (96 h-EC 50 = 65.93 µg L -1 as Cu) as compared to their analogous microcosms with modified water chemistry (96 h-EC 50 = 386.67 µg L -1 as Cu), the increased water hardness and alkalinity in the latter case contributing to the decrease of the metal bioavailability. Results from laboratory experiments showed good correlation with copper dosages used in a small scale field testing to control algae growth, increasing confidence in laboratory bioassays. Copyright © 2018 Elsevier Inc. All rights reserved.

SU-E-T-672: Real-Time In Vivo Dosimeters Using LiPCDA and Optical Fibers

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

Rink, A; Jaffray, DA; Croteau, A

2015-06-15

Purpose: To investigate dosimeter prototypes made with lithium pentacosa-10,12-diynoate (LiPCDA, the material used in GafChromic EBT films) and optical fibers for their suitability in real-time in vivo measurements. Methods: The prototypes, made with 500 µm plastic optical fibers and 8.5 µm thickness of LiPCDA at fiber tip, were irradiated with a 6 MV beam. To investigate the efficacy of pre-irradiation calibration, the probes were irradiated to 2 Gy twice, with 5 minutes in between. Net optical density values (netOD) around the main absorbance peak were compared, and effect of correcting second measurement by the first was assessed. Ageing was assessedmore » by irradiating two prototypes to 2 Gy and comparing the netOD to that obtained for 15 prototypes from the same batch 12–14 months earlier. To measure angular dependence, the probes were pre-irradiated with beam perpendicular to fiber axis and then, 5 minutes later either perpendicular or parallel to fiber axes. The thickness-corrected netOD measurements were compared. Results: Standard deviation of netOD for probes of the same batch was measured to be 5–6%. When netOD was corrected for material thickness by using results from the first irradiation, the standard deviation decreased to 1.3%. This was comparable to the uncertainty in measurements observed with a single probe and is attributed to variations in light output, spectrometer noise and splitter-to-probe connection variations. Comparison of netOD values obtained a year apart failed to illustrate statistically significant decrease in sensitivity due to ageing (0.38 ± 0.03 and 0.3656 ± 0.0003). NetOD measured with MV beam parallel to fiber was within error of netOD measured with MV beam perpendicular to fiber. Conclusion: Current prototype construction allows for shelf life of at least one year. With material thickness corrected for, the prototypes can measure dose with an uncertainty below 2% at a given energy and dose rate. This work has been funded by the Ontario Centres of Excellence Market Readiness grant. The authors have no conflict of interest to declare.« less

Comparative Investigation of Copper Tolerance and Identification of Putative Tolerance Related Genes in Tardigrades

PubMed Central

Hygum, Thomas L.; Fobian, Dannie; Kamilari, Maria; Jørgensen, Aslak; Schiøtt, Morten; Grosell, Martin; Møbjerg, Nadja

2017-01-01

Tardigrades are microscopic aquatic animals renowned for their tolerance toward extreme environmental conditions. The current study is the first to investigate their tolerance toward heavy metals and we present a novel tardigrade toxicant tolerance assay based on activity assessments as a measure of survival. Specifically, we compare tolerance toward copper in four species representing different evolutionary lineages, habitats and adaptation strategies, i.e., a marine heterotardigrade, Echiniscoides sigismundi, a limno-terrestrial heterotardigrade, Echiniscus testudo, a limno-terrestrial eutardigrade, Ramazzottius oberhaeuseri, and a marine eutardigrade, Halobiotus crispae. The latter was sampled at a time of year, when the population is predominantly represented by aberrant P1 cysts, while the other species were in normal active states prior to exposure. Based on volume measurements and a general relation between body mass and copper tolerance, expected tardigrade EC50 values were estimated at 0.5–2 μg l−1. Following 24 h of exposure, tolerance was high with no apparent link to lineage or habitat. EC50s (95% CI), 24 h after exposure, were estimated at 178 (168–186) and 310 (295–328) μg l−1, respectively, for E. sigismundi and R. oberhaeuseri, whereas E. testudo and H. crispae were less affected. Highest tolerance was observed in H. crispae with a mean ± s.e.m. activity of 77 ± 2% (n = 3) 24 h after removal from ~3 mg l−1 copper, suggesting that tardigrade cysts have increased tolerance toward toxicants. In order to identify putative tolerance related genes, an E. sigismundi transcriptome was searched for key enzymes involved in osmoregulation, antioxidant defense and copper metabolism. We found high expression of Na/K ATPase and carbonic anhydrase, known targets for copper. Our transcriptome, furthermore, revealed high expression of antioxidant enzymes, copper transporters, ATOX1, and a Cu-ATPase. In summary, our results indicate that tardigrades express well-known key osmoregulatory enzymes, supporting the hypothesis that copper inhibits sodium turnover as demonstrated for other aquatic organisms. Tardigrades, nevertheless, have high tolerance toward the toxicant, which is likely linked to high expression of antioxidant enzymes and an ability to enter dormant states. Tardigrades, furthermore, seem to have a well-developed battery of cuproproteins involved in copper homeostasis, providing basis for active copper sequestering and excretion. PMID:28293195

Comparative Investigation of Copper Tolerance and Identification of Putative Tolerance Related Genes in Tardigrades.

PubMed

Hygum, Thomas L; Fobian, Dannie; Kamilari, Maria; Jørgensen, Aslak; Schiøtt, Morten; Grosell, Martin; Møbjerg, Nadja

2017-01-01

Tardigrades are microscopic aquatic animals renowned for their tolerance toward extreme environmental conditions. The current study is the first to investigate their tolerance toward heavy metals and we present a novel tardigrade toxicant tolerance assay based on activity assessments as a measure of survival. Specifically, we compare tolerance toward copper in four species representing different evolutionary lineages, habitats and adaptation strategies, i.e., a marine heterotardigrade, Echiniscoides sigismundi , a limno-terrestrial heterotardigrade, Echiniscus testudo , a limno-terrestrial eutardigrade, Ramazzottius oberhaeuseri , and a marine eutardigrade, Halobiotus crispae . The latter was sampled at a time of year, when the population is predominantly represented by aberrant P1 cysts, while the other species were in normal active states prior to exposure. Based on volume measurements and a general relation between body mass and copper tolerance, expected tardigrade EC50 values were estimated at 0.5-2 μg l -1 . Following 24 h of exposure, tolerance was high with no apparent link to lineage or habitat. EC50s (95% CI), 24 h after exposure, were estimated at 178 (168-186) and 310 (295-328) μg l -1 , respectively, for E. sigismundi and R. oberhaeuseri , whereas E. testudo and H. crispae were less affected. Highest tolerance was observed in H. crispae with a mean ± s.e.m . activity of 77 ± 2% ( n = 3) 24 h after removal from ~3 mg l -1 copper, suggesting that tardigrade cysts have increased tolerance toward toxicants. In order to identify putative tolerance related genes, an E. sigismundi transcriptome was searched for key enzymes involved in osmoregulation, antioxidant defense and copper metabolism. We found high expression of Na/K ATPase and carbonic anhydrase, known targets for copper. Our transcriptome, furthermore, revealed high expression of antioxidant enzymes, copper transporters, ATOX1, and a Cu-ATPase. In summary, our results indicate that tardigrades express well-known key osmoregulatory enzymes, supporting the hypothesis that copper inhibits sodium turnover as demonstrated for other aquatic organisms. Tardigrades, nevertheless, have high tolerance toward the toxicant, which is likely linked to high expression of antioxidant enzymes and an ability to enter dormant states. Tardigrades, furthermore, seem to have a well-developed battery of cuproproteins involved in copper homeostasis, providing basis for active copper sequestering and excretion.

Prototype active scanner for nighttime oil spill mapping and classification

NASA Technical Reports Server (NTRS)

Sandness, G. A.; Ailes, S. B.

1977-01-01

A prototype, active, aerial scanner system was constructed for nighttime water pollution detection and nighttime multispectral imaging of the ground. An arc lamp was used to produce the transmitted light and four detector channels provided a multispectral measurement capability. The feasibility of the design concept was demonstrated by laboratory and flight tests of the prototype system.

Implicit alcohol attitudes predict drinking behaviour over and above intentions and willingness in young adults but willingness is more important in adolescents: Implications for the Prototype Willingness Model.

PubMed

Davies, Emma L; Paltoglou, Aspasia E; Foxcroft, David R

2017-05-01

Dual process models, such as the Prototype Willingness Model (PWM), propose to account for both intentional and reactive drinking behaviour. Current methods of measuring constructs in the PWM rely on self-report, thus require a level of conscious deliberation. Implicit measures of attitudes may overcome this limitation and contribute to our understanding of how prototypes and willingness influence alcohol consumption in young people. This study aimed to explore whether implicit alcohol attitudes were related to PWM constructs and whether they would add to the prediction of risky drinking. The study involved a cross-sectional design. The sample included 501 participants from the United Kingdom (M age 18.92; range 11-51; 63% female); 230 school pupils and 271 university students. Participants completed explicit measures of alcohol prototype perceptions, willingness, drunkenness, harms, and intentions. They also completed an implicit measure of alcohol attitudes, using the Implicit Association Test. Implicit alcohol attitudes were only weakly related to the explicit measures. When looking at the whole sample, implicit alcohol attitudes did not add to the prediction of willingness over and above prototype perceptions. However, for university students implicit attitudes added to the prediction of behaviour, over and above intentions and willingness. For school pupils, willingness was a stronger predictor of behaviour than intentions or implicit attitudes. Adding implicit measures to the PWM may contribute to our understanding of the development of alcohol behaviours in young people. Further research could explore how implicit attitudes develop alongside the shift from reactive to planned behaviour. Statement of contribution What is already known on this subject? Young people's drinking tends to occur in social situations and is driven in part by social reactions within these contexts. The Prototype Willingness Model (PWM) attempts to explain such reactive behaviour as the result of social comparison to risk prototypes, which influence willingness to drink, and subsequent behaviour. Evidence also suggests that risky drinking in young people may be influenced by implicit attitudes towards alcohol, which develop with repeated exposure to alcohol over time. One criticism of the PWM is that prototypes and willingness are usually measured using explicit measures which may not adequately capture young people's spontaneous evaluations of prototypes, or their propensity to act without forethought in a social context. What does this study add? This study is novel in exploring the addition of implicit alcohol attitudes to the social reaction pathway in the model in order to understand more about these reactive constructs. Implicit alcohol attitudes added to the prediction of behaviour, over and above intentions and willingness for university students. For school pupils, willingness was a stronger predictor of behaviour than intentions or implicit attitudes. Findings suggest that adding implicit alcohol attitudes into the PWM might be able to explain the shift from reactive to intentional drinking behaviours with age and experience. © 2016 The British Psychological Society.

Antimicrobial and water-triggered release characteristics of a copper sulfate-polyvinyl acetate adhesive composite

NASA Astrophysics Data System (ADS)

De Jesus, A. P. O.; Roxas-Villanueva, R. M. L.; Herrera, M. U.

2017-05-01

Water-triggered release of antimicrobial solutions is advantageous in inhibiting the growth of bacteria and fungi in moist and wet environments. In this study, we fabricated a composite, by mixing polyvinyl acetate adhesive with copper sulfate solution, which exhibits antimicrobial activities against bacteria. Polyvinyl acetate adhesive serves as the binder and water soluble substance while copper sulfate serves as the antimicrobial agent. The composite was coated in an acetate film and air-dried. To monitor the rate of release of copper ions, the composite was submerged in water and the conductivity was measured. The conductivity saturation time was determined. The composite showed antimicrobial activity against Escherichia coli (Gram-negative) and Staphylococcus aureus (Gram-positive).

Shear strength of metal - SiO2 contacts

NASA Technical Reports Server (NTRS)

Pepper, S. V.

1978-01-01

The strength of the bond between metals and SiO2 is studied by measuring the static coefficient of friction of metals contacting alpha-quartz in ultrahigh vacuum. It was found that copper with either chemisorbed oxygen, nitrogen or sulphur exhibited higher contact strength on stoichiometric SiO2 than did clean copper. Since the surface density of states induced by these species on copper is similar, it appears that the strength of the interfacial bond can be related to the density of states on the metal surface.

Shear strength of metal - SiO2 contacts

NASA Technical Reports Server (NTRS)

Pepper, S. V.

1978-01-01

The strength of the bond between metals and SiO2 was studied by measuring the static coefficient of friction of metals contacting alpha-quartz in ultrahigh vacuum. It was found that copper with either chemisorbed oxygen, nitrogen, or sulphur exhibited higher contact strength on stoichiometric SiO2 than did clean copper. Since the surface density of states induced by these species on copper is similar, it appears that the strength of the interfacial bond can be related to the density of states on the metal surface.

Copper vapor-assisted growth of hexagonal graphene domains on silica islands

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

Li, Jun; Que, Yande; Jiang, Lili

2016-07-11

Silica (SiO{sub 2}) islands with a dendritic structure were prepared on polycrystalline copper foil, using silane (SiH{sub 4}) as a precursor, by annealing at high temperature. Assisted by copper vapor from bare sections of the foil, single-layer hexagonal graphene domains were grown directly on the SiO{sub 2} islands by chemical vapor deposition. Scanning electron microscopy, atomic force microscopy, Raman spectra, and X-ray photoelectron spectroscopy confirm that hexagonal graphene domains, each measuring several microns, were synthesized on the silica islands.

Eddy current measurement of the thickness of top Cu film of the multilayer interconnects in the integrated circuit (IC) manufacturing process

NASA Astrophysics Data System (ADS)

Qu, Zilian; Meng, Yonggang; Zhao, Qian

2015-03-01

This paper proposes a new eddy current method, named equivalent unit method (EUM), for the thickness measurement of the top copper film of multilayer interconnects in the chemical mechanical polishing (CMP) process, which is an important step in the integrated circuit (IC) manufacturing. The influence of the underneath circuit layers on the eddy current is modeled and treated as an equivalent film thickness. By subtracting this equivalent film component, the accuracy of the thickness measurement of the top copper layer with an eddy current sensor is improved and the absolute error is 3 nm for sampler measurement.

Fast neutrons measured in copper from the Hiroshima atomic bomb dome.

PubMed

Marchetti, A A; McAninch, J E; Rugel, G; Rühm, W; Korschinek, G; Martinelli, R E; Faestermann, T; Knie, K; Egbert, S D; Wallner, A; Wallner, C; Tanaka, K; Endo, S; Hoshi, M; Shizuma, K; Fujita, S; Hasai, H; Imanaka, T; Straume, T

2009-01-01

The first measurements of (63)Ni produced by A-bomb fast neutrons (above approximately 1 MeV) in copper samples from Hiroshima encompassed distances from approximately 380 to 5062 m from the hypocenter (the point on the ground directly under the bomb). They included the region of interest to survivor studies (approximately 900 to 1500 m) and provided the first direct validation of fast neutrons in that range. However, a significant measurement gap remained between the hypocenter and 380 m. Measurements close to the hypocenter are important as a high-value anchor for the slope of the curve for neutron activation as a function of distance. Here we report measurements of (63)Ni in copper samples from the historic Hiroshima Atomic Bomb Dome, which is located approximately 150 m from the hypocenter. These measurements extend the range of our previously published data for (63)Ni providing a more comprehensive and consistent A-bomb activation curve. The results are also in good agreement with calculations based on the current dosimetry system (DS02) and give further experimental support to the accuracy of this system that forms the basis for radiation risk estimates worldwide.

INTEGRAL REACTION RATES AND NEUTRON ENERGY SPECTRA IN A WELL MODERATED REACTOR

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

Connolly, J.W.; Rose, A.; Wall, T.

1963-04-01

Cadmium ratio measurements in the internal reflector of MOATA were made with gold, indium, tungsten, manganese, molybdenum, and copper detectors. These measurements were analyzed on the assumption that the neutron spectrum consists of a Maxwellian distribution to which is smoothly joined a 1/E slowing down spectrum, the cross sections being averaged according to the methods of Westcott. A search through recent literature suggests that the s factors for gold and indium listed by Westcott are in error. If this is accepted, then it appears that the measured epithermal spectrum is closely 1/E in form for neutron energies between 1 andmore » 600 ev. The corrections to be applied when foils of finite thickness are used in cadmium ratio measuremerts are discussed, and the spectrum derived from these measurements was used to calculate reaction rate ratios of copper: indium and copper: gold alloy foils. These ratios were compared with measured values. Values of the effective resonance integral of Pt/sup 198/ wire detectors were measured, and from these values an estimate was made of the infinitely dilute resonance integral of this isotope. (auth)« less

Development of a system to measure local measurement conditions around textile electrodes.

PubMed

Kim, Saim; Oliveira, Joana; Roethlingshoefer, Lisa; Leonhard, Steffen

2010-01-01

The three main influence factors on the interface between textile electrode an skin are: temperature, contact pressure and relative humidity. This paper presents first results of a prototype, which measures these local measurement conditions around textile electrodes. The wearable prototype is a data acquisition system based on a microcontroller with a flexible sensor sleeve. Validation measurements included variation of ambient temperature, contact pressures and sleeve material. Results show a good correlation with data found in literature.

Design and first plasma measurements of the ITER-ECE prototype radiometer.

PubMed

Austin, M E; Brookman, M W; Rowan, W L; Danani, S; Bryerton, E W; Dougherty, P

2016-11-01

On ITER, second harmonic optically thick electron cyclotron emission (ECE) in the range of 220-340 GHz will supply the electron temperature (T e ). To investigate the requirements and capabilities prescribed for the ITER system, a prototype radiometer covering this frequency range has been developed by Virginia Diodes, Inc. The first plasma measurements with this instrument have been carried out on the DIII-D tokamak, with lab bench tests and measurements of third through fifth harmonic ECE from high T e plasmas. At DIII-D the instrument shares the transmission line of the Michelson interferometer and can simultaneously acquire data. Comparison of the ECE radiation temperature from the absolutely calibrated Michelson and the prototype receiver shows that the ITER radiometer provides accurate measurements of the millimeter radiation across the instrument band.

Design and Calibration of an Inexpensive Digital Anemometer

ERIC Educational Resources Information Center

Hernandez-Walls, R.; Rojas-Mayoral, E.; Baez-Castillo, L.; Rojas-Mayoral, B.

2008-01-01

An inexpensive and easily implemented device to measure wind velocity is proposed. This prototype has the advantage of being able to measure both the speed and the direction of the wind in two dimensions. The device utilizes a computational interface commonly referred to as a "mouse." The mouse proposed for this prototype contains an…

Fabrication of prototype for measuring the exhaled breath temperature (EBT) to support detection of asthma

NASA Astrophysics Data System (ADS)

Harnawan, A. A.; Mariati; Fahrudin, A.; Assegaf, A.

2017-05-01

Recently, EBT has been proven as the marker of airways inflammation like asthma and proposed as the non-invasive tool. Although EBT device has already been made but this device is rarely used for patients in Indonesia. The aim of this study is to develop a prototype which accurately measures EBT and is comfortably used by patients including children. This prototype was made using SHT11 as a sensor of EBT which is integrated on a thermal flask 0.5L. This flask filled up patient breath and the temperature of air breath was measured. The EBT of twelve healthy samples and seven samples with asthma was examined using this prototype, the measurement was done within three minutes for all of them. The test results of EBT on healthy samples obtained the median is 33.9°C within of 33.0°C - 34.7°C and EBT on asthma samples obtained median is 35.0°C within the range 34.9°C - 36.0°C.

Cleaning and passivation of copper surfaces to remove surface radioactivity and prevent oxide formation

NASA Astrophysics Data System (ADS)

Hoppe, E. W.; Seifert, A.; Aalseth, C. E.; Bachelor, P. P.; Day, A. R.; Edwards, D. J.; Hossbach, T. W.; Litke, K. E.; McIntyre, J. I.; Miley, H. S.; Schulte, S. M.; Smart, J. E.; Warren, G. A.

2007-08-01

High-purity copper is an attractive material for constructing ultra-low-background radiation measurement devices. Many low-background experiments using high-purity copper have indicated surface contamination emerges as the dominant background. Radon daughters plate out on exposed surfaces, leaving a residual 210Pb background that is difficult to avoid. Dust is also a problem; even under cleanroom conditions, the amount of U and Th deposited on surfaces can represent the largest remaining background. To control these backgrounds, a copper cleaning chemistry has been developed. Designed to replace an effective, but overly aggressive concentrated nitric acid etch, this peroxide-based solution allows for a more controlled cleaning of surfaces. The acidified hydrogen peroxide solution will generally target the Cu +/Cu 2+ species which are the predominant surface participants, leaving the bulk of copper metal intact. This preserves the critical tolerances of parts and eliminates significant waste disposal issues. Accompanying passivation chemistry has also been developed that protects copper surfaces from oxidation. Using a high-activity polonium surface spike, the most difficult-to-remove daughter isotope of radon, the performance of these methods are quantified.

Silver and copper nanoclusters in the lustre decoration of Italian Renaissance pottery: an EXAFS study

NASA Astrophysics Data System (ADS)

Padovani, S.; Borgia, I.; Brunetti, B.; Sgamellotti, A.; Giulivi, A.; D'Acapito, F.; Mazzoldi, P.; Sada, C.; Battaglin, G.

Lustre is one of the most important decorative techniques of the Medieval and Renaissance pottery of the Mediterranean basin, capable of producing brilliant metallic reflections and iridescence. Following the recent finding that the colour of lustre decorations is mainly determined by copper and silver nanoclusters dispersed in the glaze layer, the local environment of copper and silver atoms has been studied by extended X-ray absorption fine structure (EXAFS) spectroscopy on original samples of gold and red lustre. It has been found that, in gold lustre, whose colour is attributed mainly to the silver nanocluster dispersion, silver is only partially present in the metallic form and copper is almost completely oxidised. In the red lustre, whose colour is attributed mainly to the copper nanocluster dispersion, only a fraction of copper is present in the metallic form. EXAFS measurements on red lustre, carried out in the total electron yield mode to probe only the first 150 nm of the glaze layer, indicated that in some cases lustre nanoclusters may be confined in a very thin layer close to the surface.

Performance of Superconducting Magnet Prototypes for LCLS-II Linear Accelerator

DOE PAGES

Kashikhin, Vladimir; Andreev, Nikolai; DiMarco, Joseph; ...

2017-01-05

The new LCLS-II Linear Superconducting Accelerator at SLAC needs superconducting magnet packages installed inside SCRF Cryomodules to focus and steer an electron beam. Two magnet prototypes were built and successfully tested at Fermilab. Magnets have an iron dominated configuration, quadrupole and dipole NbTi superconducting coils, and splittable in the vertical plane configuration. Magnets inside the Cryomodule are conductively cooled through pure Al heat sinks. Both magnets performance was verified by magnetic measurements at room temperature, and during cold tests in liquid helium. Test results including magnetic measurements are discussed. Special attention was given to the magnet performance at low currentsmore » where the iron yoke and the superconductor hysteresis effects have large influence. Both magnet prototypes were accepted for the installation in FNAL and JLAB prototype Cryomodules.« less

Prototyping for LENS

NASA Astrophysics Data System (ADS)

Rasco, B. C.

2012-03-01

The Low-Energy Neutrino Spectroscopy (LENS) experiment will precisely measure the energy spectrum of low-energy solar neutrinos via charged-current neutrino reactions on indium. The LENS detector concept applies indium-loaded scintillator in an optically-segmented lattice geometry to achieve precise time and spatial resolution with unprecedented sensitivity for low-energy neutrino events. The LENS collaboration is currently developing prototypes that aim to demonstrate the performance and selectivity of the technology and to benchmark Monte Carlo simulations that will guide scaling to the full LENS instrument. Currently a 120 liter prototype, microLENS, is operating with pure scintillator (no indium loading) in the Kimballton Underground Research Facility (KURF). We will present results from initial measurements with microLENS and plans for a 400 liter prototype, miniLENS, using indium loaded scintillator that will be installed this summer.

Biomechanical Evaluation of a Prototype Foot/Ankle Prosthesis

PubMed Central

Quesada, P. M.; Pitkin, M.; Colvin, J.

2016-01-01

In this paper, we report on our pilot evaluation of a prototype foot/ankle prosthesis. This prototype has been designed and fabricated with the intention of providing decreased ankle joint stiffness during the middle portion of the stance phase of gait, and increased (i.e., more normal) knee range of motion during stance. Our evaluation involved fitting the existing prototype foot/ankle prosthesis, as well as a traditional solid ankle cushioned heel (SACH) foot, to an otherwise healthy volunteer with a below-knee (BK) amputation. We measured this individual’s lower extremity joint kinematics and kinetics during walking using a video motion analysis system and force platform. These measurements permitted direct comparison of prosthetic ankle joint stiffness and involved side knee joint motion, as well as prosthetic ankle joint moment and power. PMID:10779119

[Rapid prototyping in planning reconstructive surgery of the head and neck. Review and evaluation of indications in clinical use].

PubMed

Bill, J S; Reuther, J F

2004-05-01

The aim was to define the indications for use of rapid prototyping models based on data of patients treated with this technique. Since 1987 our department has been developing methods of rapid prototyping in surgery planning. During the study, first the statistical and reproducible anatomical precision of rapid prototyping models was determined on pig skull measurements depending on CT parameters and method of rapid prototyping. Measurements on stereolithography models and on selective laser sintered models confirmed an accuracy of +/-0.88 mm or 2.7% (maximum deviation: -3.0 mm to +3.2 mm) independently from CT parameters or method of rapid prototyping, respectively. With the same precision of models multilayer helical CT with a higher rate is the preferable method of data acquisition compared to conventional helical CT. From 1990 to 2002 in atotal of 122 patients, 127 rapid prototyping models were manufactured: in 112 patients stereolithography models, in 2 patients an additional stereolithography model, in 2 patients an additional selective laser sinter model, in 1 patient an additional milled model, and in 10 patients just a selective laser sinter model. Reconstructive surgery, distraction osteogenesis including midface distraction, and dental implantology are proven to be the major indications for rapid prototyping as confirmed in a review of the literature. Surgery planning on rapid prototyping models should only be used in individual cases due to radiation dose and high costs. Routine use of this technique only seems to be indicated in skull reconstruction and distraction osteogenesis.

Accumulation and hyperaccumulation of copper in plants

NASA Astrophysics Data System (ADS)

Adam, V.; Trnkova, L.; Huska, D.; Babula, P.; Kizek, R.

2009-04-01

Copper is natural component of our environment. Flow of copper(II) ions in the environment depends on solubility of compounds containing this metal. Mobile ion coming from soil and rocks due to volcanic activity, rains and others are then distributed to water. Bio-availability of copper is substantially lower than its concentration in the aquatic environment. Copper present in the water reacts with other compounds and creates a complex, not available for organisms. The availability of copper varies depending on the environment, but moving around within the range from 5 to 25 % of total copper. Thus copper is stored in the sediments and the rest is transported to the seas and oceans. It is common knowledge that copper is essential element for most living organisms. For this reason this element is actively accumulated in the tissues. The total quantity of copper in soil ranges from 2 to 250 mg / kg, the average concentration is 30 mg / kg. Certain activities related to agriculture (the use of fungicides), possibly with the metallurgical industry and mining, tend to increase the total quantity of copper in the soil. This amount of copper in the soil is a problem particularly for agricultural production of food. The lack of copper causes a decrease in revenue and reduction in quality of production. In Europe, shows the low level of copper in total 18 million hectares of farmland. To remedy this adverse situation is the increasing use of copper fertilizers in agricultural soils. It is known that copper compounds are used in plant protection against various illnesses and pests. Mining of minerals is for the development of human society a key economic activity. An important site where the copper is mined in the Slovakia is nearby Smolníka. Due to long time mining in his area (more than 700 years) there are places with extremely high concentrations of various metals including copper. Besides copper, there are also detected iron, zinc and arsenic. Various plant species have adapted on such stress. The aim of this study is to investigate the behaviour of copper in plants and to assess its potential effect on the surrounding environment. To detect copper in biological samples electrochemical methods were employed particularly differential pulse voltammetry (DPV). Copper gave signals at 0.02 V measured by DPV. The obtained calibration dependence was linear (R2 = 0.995). Further, this method was utilized for determination of copper in real soil samples obtained from previously mentioned heavy-metal-polluted mining area. The content varied within range from tens to hundreds of mg of copper per kg of the soil. Moreover, we focused on investigation of copper influence on seedlings of Norway spruce. The seedlings were treated with copper (0, 0.1, 10 and 100 mM) for four weeks. We observed anatomical-morphological changes and other biochemical parameters in plants. We determined that seedlings synthesized more than 48 % protective thiols (glutathione and phytochelatins) compared to control ones. We investigated copper distribution in plant tissues by diphenylcarbazide staining. We found out that copper is highly accumulated in parenchymal stalk cells. In needles, change in auto-fluorescence of parenchymal cells of mesoderm similarly to endodermis cells. Besides, we analyzed samples of plants from the polluted area (spruce, pin, birch). The data obtained well correlated with previously mentioned. Acknowledgement The work on this experiment was supported by grant: INCHEMBIOL MSM0021622412.

Evaluation of the possible role of copper ions in drinking water in the pathogenesis of oral submucous fibrosis: a pilot study.

PubMed

Arakeri, Gururaj; Patil, Shekhar Gowda; Ramesh, D N S V; Hunasgi, Santosh; Brennan, Peter A

2014-01-01

We aimed to investigate the concentration of copper ions in drinking water and to assess whether copper has a role in the pathogenesis of oral submucous fibrosis (OSMF). We studied 50 patients with clinically and histologically diagnosed OSMF from the Yadgir district of Karnataka in India. Fifty healthy people matched for age and sex were used as controls. In both groups concentrations of copper ions in serum, saliva, and home drinking water were measured using atomic absorption spectroscopy and intelligent nephelometry technology. Serum ceruloplasmin concentrations were also estimated in both groups. The mean (SD) concentration of copper in the home drinking water of patients with OSMF was significantly higher (764.3 (445.9)μmol/L) than in the controls (305.7 (318.5)μmol/L) (p<0.001). Patients with OSMF also had a significantly higher copper concentrations in serum and saliva, and serum ceruloplasmin than controls (p<0.001). For the first time these data have shown a positive association between copper concentrations in home drinking water and OSMF. It raises the possibility that increased copper in drinking water contributes to the development of OSMF, and adds to that ingested when areca nut is chewed. Copyright © 2013 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

Systemic serum amyloid A as a biomarker for exposure to zinc and/or copper-containing metal fumes.

PubMed

Baumann, R; Gube, M; Markert, A; Davatgarbenam, S; Kossack, V; Gerhards, B; Kraus, T; Brand, P

2018-01-01

Zinc- and copper-containing welding fumes increase systemic C-reactive protein (CRP). The aim of this study was to investigate the performance of the biomarkers serum amyloid A (SAA) and soluble vascular cell adhesion molecule-1 (VCAM-1) in this regard. Fifteen male subjects were exposed under controlled conditions to welding fumes containing either zinc, or copper, or copper and zinc for 6 h. Plasma samples were collected before, 6 and 24 h after start of exposure and biomarkers therein were measured by electrochemiluminescent assay. For each exposure, systemic concentrations of systemic SAA, but not VCAM-1, increased significantly at 24 h after exposure start compared with baseline ("copper only": P=0.0005, "zinc only": P=0.027, "copper and zinc": P=0.001). SAA showed a wider range of concentrations than did CRP and its levels increased up to 19-fold after welding fume exposure. The recognition of copper as a potential harmful component in welding fumes, also independent from zinc, deserves further consideration. SAA might represent a new sensitive biomarker for potential subclinical sterile inflammation after inhalation of copper- and/or zinc-containing welding fumes. As elevations of CRP and SAA protein have both been linked to a higher risk for cardiovascular disease, these findings might particularly be important for long-term welders.

Studies of a full-scale mechanical prototype line for the ANTARES neutrino telescope and tests of a prototype instrument for deep-sea acoustic measurements

NASA Astrophysics Data System (ADS)

Ageron, M.; Aguilar, J. A.; Albert, A.; Ameli, F.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardellier-Desages, F.; Aslanides, E.; Aubert, J.-J.; Auer, R.; Barbarito, E.; Basa, S.; Battaglieri, M.; Bazzotti, M.; Becherini, Y.; Béthoux, N.; Beltramelli, J.; Bertin, V.; Bigi, A.; Billault, M.; Blaes, R.; de Botton, N.; Bouwhuis, M. C.; Bruijn, R.; Brunner, J.; Burgio, G. F.; Busto, J.; Cafagna, F.; Caillat, L.; Calzas, A.; Capone, A.; Caponetto, L.; Carmona, E.; Carr, J.; Castel, D.; Castorina, E.; Cavasinni, V.; Cecchini, S.; Ceres, A.; Charvis, P.; Chauchot, P.; Chiarusi, T.; Circella, M.; Coail, J.-Y.; Colnard, C.; Compére, C.; Coniglione, R.; Cottini, N.; Coyle, P.; Cuneo, S.; Cussatlegras, A.-S.; Damy, G.; van Dantzig, R.; Debonis, G.; de Marzo, C.; de Vita, R.; Dekeyser, I.; Delagnes, E.; Denans, D.; Deschamps, A.; Dessa, J.-X.; Destelle, J.-J.; Dinkespieler, B.; Distefano, C.; Donzaud, C.; Drogou, J.-F.; Druillole, F.; Durand, D.; Ernenwein, J.-P.; Escoffier, S.; Falchini, E.; Favard, S.; Fehr, F.; Feinstein, F.; Fiorello, C.; Flaminio, V.; Fratini, K.; Fuda, J.-L.; Galeotti, S.; Gallone, J.-M.; Giacomelli, G.; Girard, N.; Gojak, C.; Goret, Ph.; Graf, K.; Guilloux, F.; Hallewell, G.; Harakeh, M. N.; Hartmann, B.; Heijboer, A.; Heine, E.; Hello, Y.; Hernández-Rey, J. J.; Hößl, J.; Hoffman, C.; Hogenbirk, J.; Hubbard, J. R.; Jaquet, M.; Jaspers, M.; de Jong, M.; Jouvenot, F.; Kalantar-Nayestanaki, N.; Kappes, A.; Karg, T.; Katz, U.; Keller, P.; Kneib, J. P.; Kok, E.; Kok, H.; Kooijman, P.; Kopper, C.; Kouchner, A.; Kretschmer, W.; Kruijer, A.; Kuch, S.; Lagier, P.; Lahmann, R.; Lamanna, G.; Lamare, P.; Lambard, G.; Languillat, J. C.; Laschinsky, H.; Lavalle, J.; Le Guen, Y.; Le Provost, H.; Le van Suu, A.; Lefévre, D.; Legou, T.; Lelaizant, G.; Lim, G.; Lo Presti, D.; Loaec, G.; Loehner, H.; Loucatos, S.; Louis, F.; Lucarelli, F.; Lyashuk, V.; Mangano, S.; Marcelin, M.; Margiotta, A.; Masullo, R.; Mazéas, F.; Mazure, A.; Megna, R.; Melissas, M.; Migneco, E.; Mongelli, M.; Montaruli, T.; Morganti, M.; Moscoso, L.; Motz, H.; Musumeci, M.; Naumann, C.; Naumann-Godo, M.; Niess, V.; Noble, A.; Olivetto, C.; Ostasch, R.; Palanque-Delabrouille, N.; Payre, P.; Peek, H. Z.; Perez, A.; Petta, C.; Piattelli, P.; Pillet, R.; Pineau, J.-P.; Poinsignon, J.; Popa, V.; Pradier, T.; Racca, C.; Randazzo, N.; van Randwijk, J.; Real, D.; Regnier, M.; van Rens, B.; Réthoré, F.; Rewiersma, P.; Riccobene, G.; Rigaud, V.; Ripani, M.; Roca, V.; Roda, C.; Rolin, J. F.; Rostovtsev, A.; Roux, J.; Ruppi, M.; Russo, G. V.; Rusydi, G.; Salesa, F.; Salomon, K.; Sapienza, P.; Schmitt, F.; Schuller, J.-P.; Shanidze, R.; Sokalski, I.; Spona, T.; Spurio, M.; van der Steenhoven, G.; Stolarczyk, T.; Streeb, K.; Sulak, L.; Taiuti, M.; Tamburini, C.; Tao, C.; Tasca, L.; Terreni, G.; Urbano, F.; Valdy, P.; Valente, V.; Vallage, B.; Vaudaine, G.; Venekamp, G.; Verlaat, B.; Vernin, P.; van Wijk, R.; Wijnker, G.; Wobbe, G.; de Wolf, E.; Yao, A.-F.; Zaborov, D.; Zaccone, H.; Zornoza, J. D.; Zúñiga, J.

2007-11-01

A full-scale mechanical prototype line was deployed to a depth of 2500 m to test the leak tightness of the electronics containers and the pressure-resistant properties of an electromechanical cable under evaluation for use in the ANTARES deep-sea neutrino telescope. During a month-long immersion study, line parameter data were taken using miniature autonomous data loggers and shore-based optical time domain reflectometry. Details of the mechanical prototype line, the electromechanical cable and data acquisition are presented. Data taken during the immersion study revealed deficiencies in the pressure resistance of the electromechanical cable terminations at the entry points to the electronics containers. The improvements to the termination, which have been integrated into subsequent detection lines, are discussed. The line also allowed deep-sea acoustic measurements with a prototype hydrophone system. The technical setup of this system is described, and the first results of the data analysis are presented.

Effects of a copper-tolerant grass (Agrostis capillaris) on the ecosystem of a copper-contaminated arable soil

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

Boon, G.T.; Bouwman, L.A.; Bloem, J.

1998-10-01

To test how a dysfunctioning ecosystem of a severely metal-polluted soil responds to renewed plant growth, a pot experiment was conducted with soil from an experimental arable field with pH and copper gradients imposed 13 years ago. In this experiment, four pH/copper combinations from this field were either planted with a pH- and copper-resistant grass cultivar or remained fallow. During a 10-week period, the dynamics of the microbial activity and of the abundances of bacteria, protozoa. and nematodes were measured, as were the dynamics of several chemical soil parameters. After 13 years of copper, which had resulted in severely reducedmore » crop growth, no effects were observed on bacterial numbers, respiration, or protozoan numbers, but bacterial growth was strongly reduced in the low pH plots, and even more so in low pH plots enriched with copper. Of the organisms, only nematodes were negatively affected under conditions of high copper load at low pH. In these plots, numbers belonging to all feeding categories were strongly reduced. Planting of a copper-tolerant grass variety, Agrostis capillaris L. var. Parys Mountain, resulted within 10 weeks in faster bacterial growth and more protozoa and bacterivorous nematodes in comparison with fallow controls; these effects were markedly strongest in the acidic, copper-enriched soils. During incubation, fungivorous nematodes increased in all treatments, in fallow and in planted pots and in the pots with high-copper, low-pH soil. The results of this experiment suggest that introduction of plant growth is one of the major causes of increased biological activity in acidic contaminated soils. Planting such soils with metal-tolerant plant species can reestablish the necessary food base to support soil organism growth, and this can lead to numerous positive effects, reversing the loss of soil functions due to the high copper levels under acidic conditions.« less

Metal lost and found: dissipative uses and releases of copper in the United States 1975-2000.

PubMed

Lifset, Reid J; Eckelman, Matthew J; Harper, E M; Hausfather, Zeke; Urbina, Gonzalo

2012-02-15

Metals are used in a variety of ways, many of which lead to dissipative releases to the environment. Such releases are relevant from both a resource use and an environmental impact perspective. We present a historical analysis of copper dissipative releases in the United States from 1975 to 2000. We situate all dissipative releases in copper's life cycle and introduce a conceptual framework by which copper dissipative releases may be categorized in terms of intentionality of use and release. We interpret our results in the context of larger trends in production and consumption and government policies that have served as drivers of intentional copper releases from the relevant sources. Intentional copper releases are found to be both significant in quantity and highly variable. In 1975, for example, the largest source of intentional releases was from the application of copper-based pesticides, and this decreased more than 50% over the next 25 years; all other sources of intentional releases increased during that period. Overall, intentional copper releases decreased by approximately 15% from 1975 to 2000. Intentional uses that are unintentionally released such as copper from roofing, increased by the same percentage. Trace contaminant sources such as fossil fuel combustion, i.e., sources where both the use and the release are unintended, increased by nearly 50%. Intentional dissipative uses are equivalent to 60% of unintentional copper dissipative releases and more than five times that from trace sources. Dissipative copper releases are revealed to be modest when compared to bulk copper flows in the economy, and we introduce a metric, the dissipation index, which may be considered an economy-wide measure of resource efficiency for a particular substance. We assess the importance of dissipative releases in the calculation of recycling rates, concluding that the inclusion of dissipation in recycling rate calculations has a small, but discernible, influence, and should be included in such calculations. Copyright © 2011 Elsevier B.V. All rights reserved.

Relationship among aqueous copper half-lives and responses of Pimephales promelas to a series of copper sulfate pentahydrate concentrations.

PubMed

Calomeni, Alyssa J; Kinley, Ciera M; Geer, Tyler D; Iwinski, Kyla J; Hendrikse, Maas; Rodgers, John H

2018-04-01

Copper algaecide exposures in situ are often of shorter duration than exposures for static toxicity experiments because aqueous concentrations in situ dissipate as a function of site-specific fate processes. Consequently, responses of organisms to static copper exposures may overestimate effects following in situ exposures. To understand the role of exposure duration for altering responses, Pimephales promelas survival was compared following static (96 h) and pulse (1.5, 4, 8, and 15 h half-lives) exposures of CuSO 4 •5H 2 O. Copper concentrations sorbed by fry indicated a consequence of different exposures. Responses of P. promelas to static exposures resulted in 96 h LC 50 s of 166 µgCu/L (95% confidence interval [CI], 142-189 µgCu/L) as soluble copper and 162 µgCu/L (CI, 140-183 µgCu/L) as acid soluble copper. Relative to static 96 h LC 50 s, exposures with half-lives of 1.5, 4 and 8 h resulted in LC 50 s 10, 3 and 2 times greater, respectively, for responses measured 96 h after exposure initiation. Copper concentrations extracted from fry exposed for 1.5, 4 and 8 h half-lives were less than the static experiment. However, copper sorbed by fry in the 15 h half-life experiment was not different than the static experiment. The relationship between 96 h LC 50 and 1/half-life was expressed using the equations y = 116 + 1360 × (R 2  = 0.97) for soluble copper and y = 147 + 1620 × (R 2  = 0.98) for acid soluble copper. Incorporation of exposure duration for predictions of P. promelas responses to copper pulse exposures increases prediction accuracy by an order of magnitude.

Fate and Transport of Elemental Copper (Cu0) Nanoparticles through Saturated Porous Media in the Presence of Organic Materials

EPA Science Inventory

Column experiments were performed to assess the fate and transport of nanoscale elemental copper (Cu0) particles in saturated quartz sands. Both effluent concentrations and retention profiles were measured over a broad range of physicochemical conditions, which included pH, ionic...

Ecological-Evaluation of Organotin-Contaminated Sediment.

DTIC Science & Technology

1985-07-01

the potential for bioaccumulation of cadmium, chromium, copper, mercury , silver, pesticides, PCBs, petroleum hydrocarbons, and organotins RESULTS The...tissues were frozen for subsequent bioaccumulation estimates. Tissues and sediment samples were analyzed for cadmium, chromium, copper, mercury , silver...spectroscopy; mercury was analyzed by cold vapor atomic absorption spectroscopy. Pesticides, PCBs, and petroleum hydrocarbons were measured by gas

The Use of Stimulable Bioluminescence From Dinoflagellates as a Means of Detecting Toxicity in the Marine Environment

DTIC Science & Technology

1993-03-01

tributyltin chloride (TFITCI), Copper (11) Sulfate (CuSO 4 I. zinc sulfate (ZnSO4 ), or storm drain effluent. Stimulable bioluminescence was measured at...to several metals and storm drain effluent. Dinoflagellate cells were exposed to various concentrations of tributyltin chloride (TBI1C), copper (II

Early-Stage Research & Development | Transportation Research | NREL

Science.gov Websites

thermal conductivity of packed copper wire used in electric-drive vehicle motor applications provides a research on thermal management in copper-wound electric motors is helping to improve the performance and reliability of electric-drive vehicles. Photo by Kevin Bennion, NREL. Anisotropic Thermal Measurement Study

Aligned copper nanorod arrays for highly efficient generation of intense ultra-broadband THz pulses

NASA Astrophysics Data System (ADS)

Mondal, S.; Wei, Q.; Ding, W. J.; Hafez, H. A.; Fareed, M. A.; Laramée, A.; Ropagnol, X.; Zhang, G.; Sun, S.; Sheng, Z. M.; Zhang, J.; Ozaki, T.

2017-01-01

We demonstrate an intense broadband terahertz (THz) source based on the interaction of relativistic-intensity femtosecond lasers with aligned copper nanorod array targets. For copper nanorod targets with a length of 5 μm, a maximum 13.8 times enhancement in the THz pulse energy (in ≤20 THz spectral range) is measured as compared to that with a thick plane copper target under the same laser conditions. A further increase in the nanorod length leads to a decrease in the THz pulse energy at medium frequencies (≤20 THz) and increase of the electromagnetic pulse energy in the high-frequency range (from 20-200 THz). For the latter, we measure a maximum energy enhancement of 28 times for the nanorod targets with a length of 60 μm. Particle-in-cell simulations reveal that THz pulses are mostly generated by coherent transition radiation of laser produced hot electrons, which are efficiently enhanced with the use of nanorod targets. Good agreement is found between the simulation and experimental results.

Aligned copper nanorod arrays for highly efficient generation of intense ultra-broadband THz pulses.

PubMed

Mondal, S; Wei, Q; Ding, W J; Hafez, H A; Fareed, M A; Laramée, A; Ropagnol, X; Zhang, G; Sun, S; Sheng, Z M; Zhang, J; Ozaki, T

2017-01-10

We demonstrate an intense broadband terahertz (THz) source based on the interaction of relativistic-intensity femtosecond lasers with aligned copper nanorod array targets. For copper nanorod targets with a length of 5 μm, a maximum 13.8 times enhancement in the THz pulse energy (in ≤20 THz spectral range) is measured as compared to that with a thick plane copper target under the same laser conditions. A further increase in the nanorod length leads to a decrease in the THz pulse energy at medium frequencies (≤20 THz) and increase of the electromagnetic pulse energy in the high-frequency range (from 20-200 THz). For the latter, we measure a maximum energy enhancement of 28 times for the nanorod targets with a length of 60 μm. Particle-in-cell simulations reveal that THz pulses are mostly generated by coherent transition radiation of laser produced hot electrons, which are efficiently enhanced with the use of nanorod targets. Good agreement is found between the simulation and experimental results.

Aligned copper nanorod arrays for highly efficient generation of intense ultra-broadband THz pulses

PubMed Central

Mondal, S.; Wei, Q.; Ding, W. J.; Hafez, H. A.; Fareed, M. A.; Laramée, A.; Ropagnol, X.; Zhang, G.; Sun, S.; Sheng, Z. M.; Zhang, J.; Ozaki, T.

2017-01-01

We demonstrate an intense broadband terahertz (THz) source based on the interaction of relativistic-intensity femtosecond lasers with aligned copper nanorod array targets. For copper nanorod targets with a length of 5 μm, a maximum 13.8 times enhancement in the THz pulse energy (in ≤20 THz spectral range) is measured as compared to that with a thick plane copper target under the same laser conditions. A further increase in the nanorod length leads to a decrease in the THz pulse energy at medium frequencies (≤20 THz) and increase of the electromagnetic pulse energy in the high-frequency range (from 20–200 THz). For the latter, we measure a maximum energy enhancement of 28 times for the nanorod targets with a length of 60 μm. Particle-in-cell simulations reveal that THz pulses are mostly generated by coherent transition radiation of laser produced hot electrons, which are efficiently enhanced with the use of nanorod targets. Good agreement is found between the simulation and experimental results. PMID:28071764

Measuring Fluxes Of Heat To A Plasma-Arc Anode

NASA Technical Reports Server (NTRS)

Sankovic, John M.; Menart, James A.; Pfender, Emil; Heberlein, Joachim

1995-01-01

Three probes constructed to provide measurements indicative of conductive, convective, and radiative transfer of heat from free-burning plasma arc to water-cooled copper anode used in generating arc. Each probe consists mainly of copper body with two thermocouples embedded at locations 4 mm apart along length. Thermocouples provide measure of rate of conduction of heat along probe and transfers of heat from plasma to sensing surface at tip of probe. Probes identical except sensing surface of one uncoated and other two coated with different materials to make them sensitive to different components of overall flux of heat.

Characterization and reduction of gradient-induced eddy currents in the RF shield of a TEM resonator.

PubMed

Alecci, Marcello; Jezzard, Peter

2002-08-01

Radiofrequency (RF) shields that surround MRI transmit/receive coils should provide effective RF screening, without introducing unwanted eddy currents induced by gradient switching. Results are presented from a detailed examination of an effective RF shield design for a prototype transverse electromagnetic (TEM) resonator suitable for use at 3 Tesla. It was found that effective RF shielding and low eddy current sensitivity could be achieved by axial segmentation (gap width = 2.4 mm) of a relatively thick (35 microm) copper shield, etched on a kapton polyimide substrate. This design has two main advantages: first, it makes the TEM less sensitive to the external environment and RF interference; and second, it makes the RF shield mechanically robust and easy to handle and assemble. Copyright 2002 Wiley-Liss, Inc.

SU-C-213-05: Evaluation of a Composite Copper-Plastic Material for a 3D Printed Radiation Therapy Bolus

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

Vitzthum, L; Ehler, E; Sterling, D

2015-06-15

Purpose: To evaluate a novel 3D printed bolus fabricated from a copper-plastic composite as a thin flexible, custom fitting device that can replicate doses achieved with conventional bolus techniques. Methods: Two models of bolus were created on a 3D printer using a composite copper-PLA/PHA. Firstly, boluses were constructed at thicknesses of 0.4, 0.6 and 0.8 mm. Relative dose measurements were performed under the bolus with an Attix Chamber as well as with radiochromic film. Results were compared to superficial Attix Chamber measurements in a water equivalent material to determine the dosimetric water equivalence of the copper-PLA/PHA plastic. Secondly, CT imagesmore » of a RANDO phantom were used to create a custom fitting bolus across the anterolateral scalp. Surface dose with the bolus placed on the RANDO phantom was measured with radiochromic film at tangential angles with 6, 10, 10 flattening filter free (FFF) and 18 MV photon beams. Results: Mean surface doses for 6, 10, 10FFF and 18 MV were measured as a percent of Dmax for the flat bolus devices of each thickness. The 0.4 mm thickness bolus was determined to be near equivalent to 2.5 mm depth in water for all four energies. Surface doses ranged from 59–63% without bolus and 85–90% with the custom 0.4 mm copper-plastic bolus relative to the prescribed dose for an oblique tangential beam arrangement on the RANDO phantom. Conclusion: Sub-millimeter thickness, 3D printed composite copper-PLA/PHA bolus can provide a build-up effect equivalent to conventional bolus. At this thickness, the 3D printed bolus allows a level of flexure that may provide more patient comfort than current 3D printing materials used in bolus fabrication while still retaining the CT based custom patient shape. Funding provided by an intra-department grant of the University of Minnesota Department of Radiation Oncology.« less

Analyse de la formation des phases du systeme cuivre-germanium par diffraction des rayons X sur des echantillons d'epaisseur nanoscopique

NASA Astrophysics Data System (ADS)

Aubin, Alexandre

With the miniaturization of electronic devices, driven by cost reduction and performance increase, new materials have to be introduced in their fabrication process to solve many emerging problems. These challenges are brought forth by the ITRS (International Technology Roadmap for Semiconductors), a comity in charge of listing the technological needs for the upcoming generations of integrated circuits. Many fields of interest require new technological developments, from global to local interconnections, the transistor gate, the gate insulator thickness, etc. One of the major challenges mentioned in the ITRS roadmap is the need for a new interconnection material. Indeed, the need for a diffusion barrier for the copper lines in local and global interconnections of integrated circuits, the main technology in today's devices, is becoming more hindering with the decrease of the metallization lines. cross-section. In the 90's, a binary compound of copper and germanium, known as the epsilon1-Cu3Ge phase, was investigated as a replacement for aluminum because of its low resistivity, that can reach as low as 5.5muO·cm [1], its stability in contact with both silicon and silicon oxide [2] as well as its thermal stability during anneals [3]. However, copper proved to be a better choice at the time because of its low bulk resistivity of 1.68muO·cm at room temperature[4]. The objective of this master thesis is to re-examine the copper-germanium system, and more specifically the epsilon1-Cu3Ge, for future applications in the microelectronics industry. Different X ray diffraction techniques were used to obtain more information on the system, including in situ X ray diffraction during 3°C/s anneals in an inert helium atmosphere with simultaneous resistance measurement, theta-2theta scans to detect diffraction peaks of the present phases after sample quenching as well as partial acquisition of the reciprocal space of quenched samples which allowed to obtain pole figures for d-spacings of interest. Results obtained on germanium and copper bilayers of total thicknesses between 20nm and 89nm deposited on an inert silicon nitride layer using magnetron sputtering in an MRC-673 show that with an atomic copper concentration between 72 and 87%, the epsilon1-Cu3Ge phase starts to form between 180°C and 210°C during a 3°C/s ramp anneal. At 72% at. copper (50nm thickness) and 75% at. copper (20nm thickness), the epsilon1-Cu3Ge phase is stable above 500°C. However, the measured resistance of the 50nm sample is low between 220°C and 500°C while measured resistance for the 20nm sample it decreases by 45% between 205 and 540°C. At a temperature of 540°C, measured resistance is 10% smaller than on the initial bilayer at room temperature. This value of measured resistance is the same at the end of the measurement during the cooling of the sample at 230°C., which implies that the low resistance is kept after the phase formation. Smaller technology nodes may then require higher formation temperatures to completely form the epsilon1-Cu3Ge phase. Further challenges thus exist to make epsilon1-Cu3Ge interconnections in modern microelectronics devices. Tests with deposition techniques like co-deposition and multilayer stacks of germanium and copper must be made to determine if they can help resolve this problem. Another field of interest for further tests are isothermal anneals, which would allow the formation of the epsilon1-Cu3Ge phase during longer anneals at lower temperatures. This thesis also allowed the acquisition of the phase formation sequence of different samples thicknesses between 20 and 89nm and copper concentrations between 72 and 87% atomic copper during 3°C/s anneals up to 850°C using in situ X ray diffraction. Brand new information was acquired on the metastable phases of the copper-germanium system. Observed diffraction peaks allowed to confirm the crystalline structures observed by Schubert and Brandauer in the 50's [5] as well as estimate the cell parameter of the body centered cubic epsilon2- Cu3Ge, which is approximately 5.03 A. Simultaneous formation of zeta-Cu5Ge and epsilon1-Cu 3Ge was also observed in a 82 % at. copper sample, which had not previously been reported in the literature.

Ecological risk assessment of copper and cadmium in surface waters of Chesapeake Bay watershed

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

Hall, L.W. Jr.; Scott, M.C.; Killen, W.D.

1998-06-01

This ecological risk assessment was designed to characterize risk of copper and cadmium exposure in the Chesapeake Bay watershed by comparing the probability distributions of environmental exposure concentrations with the probability distributions of species response data determined from laboratory studies. The overlap of these distributions was a measure of risk to aquatic life. Dissolved copper and cadmium exposure data were available from six primary data sources covering 102 stations in 18 basins in the Chesapeake Bay watershed from 1985 through 1996. Highest environmental concentrations of copper (based on 90th percentiles) were reported in the Chesapeake and Delaware (C and D)more » Canal, Choptank River, Middle River, and Potomac River; the lowest concentrations of copper were reported in the lower and middle mainstem Chesapeake Bay and Nanticoke River. Based on the calculation of 90th percentiles, cadmium concentrations were highest in the C and D Canal, Potomac River, Upper Chesapeake Bay, and West Chesapeake watershed. Lowest environmental concentrations of cadmium were reported in the lower and middle mainstem Chesapeake Bay and Susquehanna River. The ecological effects data used for this risk assessment were derived primarily from acute copper and cadmium laboratory toxicity tests conducted in both fresh water and salt water; chronic data were much more limited. The 10th percentile (concentration protecting 90% of the species) for all species derived from the freshwater acute copper toxicity database was 8.3 {micro}g/L. For acute saltwater copper data, the 10th percentile for all species was 6.3 {micro}g/L copper. The acute 10th percentile for all saltwater species was 31.7 {micro}g/L cadmium. Highest potential ecological risk from copper exposures was reported in the C and D Canal area of the northern Chesapeake Bay watershed.« less

Dynamical features in fetal and postnatal zinc-copper metabolic cycles predict the emergence of autism spectrum disorder

PubMed Central

Curtin, Paul; Curtin, Austen; Gennings, Chris; Arora, Manish; Siper, Paige; Meyering, Kristin; Kolevzon, Alexander; Mollon, Josephine; Zammit, Stanley; Wright, Robert O.; Reichenberg, Abraham

2018-01-01

Metals are critical to neurodevelopment, and dysregulation in early life has been documented in autism spectrum disorder (ASD). However, underlying mechanisms and biochemical assays to distinguish ASD cases from controls remain elusive. In a nationwide study of twins in Sweden, we tested whether zinc-copper cycles, which regulate metal metabolism, are disrupted in ASD. Using novel tooth-matrix biomarkers that provide direct measures of fetal elemental uptake, we developed a predictive model to distinguish participants who would be diagnosed with ASD in childhood from those who did not develop the disorder. We replicated our findings in three independent studies in the United States and the UK. We show that three quantifiable characteristics of fetal and postnatal zinc-copper rhythmicity are altered in ASD: the average duration of zinc-copper cycles, regularity with which the cycles recur, and the number of complex features within a cycle. In all independent study sets and in the pooled analysis, zinc-copper rhythmicity was disrupted in ASD cases. In contrast to controls, in ASD cases, the cycle duration was shorter (F = 52.25, P < 0.001), regularity was reduced (F = 47.99, P < 0.001), and complexity diminished (F = 57.30, P < 0.001). With two distinct classification models that used metal rhythmicity data, we achieved 90% accuracy in classifying cases and controls, with sensitivity to ASD diagnosis ranging from 85 to 100% and specificity ranging from 90 to 100%. These findings suggest that altered zinc-copper rhythmicity precedes the emergence of ASD, and quantitative biochemical measures of metal rhythmicity distinguish ASD cases from controls. PMID:29854952

The influence of prototype fidelity and aesthetics of design in usability tests: effects on user behaviour, subjective evaluation and emotion.

PubMed

Sauer, Juergen; Sonderegger, Andreas

2009-07-01

An empirical study examined the impact of prototype fidelity on user behaviour, subjective user evaluation and emotion. The independent factors of prototype fidelity (paper prototype, computer prototype, fully operational appliance) and aesthetics of design (high vs. moderate) were varied in a between-subjects design. The 60 participants of the experiment were asked to complete two typical tasks of mobile phone usage: sending a text message and suppressing a phone number. Both performance data and a number of subjective measures were recorded. The results suggested that task completion time may be overestimated when a computer prototype is being used. Furthermore, users appeared to compensate for deficiencies in aesthetic design by overrating the aesthetic qualities of reduced fidelity prototypes. Finally, user emotions were more positively affected by the operation of the more attractive mobile phone than by the less appealing one.

Tuning of structural, light emission and wetting properties of nanostructured copper oxide-porous silicon matrix formed on electrochemically etched copper-coated silicon substrates

NASA Astrophysics Data System (ADS)

Naddaf, M.

2017-01-01

Matrices of copper oxide-porous silicon nanostructures have been formed by electrochemical etching of copper-coated silicon surfaces in HF-based solution at different etching times (5-15 min). Micro-Raman, X-ray diffraction and X-ray photoelectron spectroscopy results show that the nature of copper oxide in the matrix changes from single-phase copper (I) oxide (Cu2O) to single-phase copper (II) oxide (CuO) on increasing the etching time. This is accompanied with important variation in the content of carbon, carbon hydrides, carbonyl compounds and silicon oxide in the matrix. The matrix formed at the low etching time (5 min) exhibits a single broad "blue" room-temperature photoluminescence (PL) band. On increasing the etching time, the intensity of this band decreases and a much stronger "red" PL band emerges in the PL spectra. The relative intensity of this band with respect to the "blue" band significantly increases on increasing the etching time. The "blue" and "red" PL bands are attributed to Cu2O and porous silicon of the matrix, respectively. In addition, the water contact angle measurements reveal that the hydrophobicity of the matrix surface can be tuned from hydrophobic to superhydrophobic state by controlling the etching time.

Cancer risk in relation to serum copper levels.

PubMed

Coates, R J; Weiss, N S; Daling, J R; Rettmer, R L; Warnick, G R

1989-08-01

A nested, matched case-control study was conducted to assess the relationship between serum levels of copper and the subsequent risk of cancer. One hundred thirty-three cases of cancer were identified during 1974-1984 among 5000 members of a northwest Washington State employee cohort from whom serum specimens had been previously obtained and stored. Two hundred forty-one controls were selected at random from the cohort and were matched to the cases on the basis of age, sex, race, and date of blood draw. Serum copper levels were measured by atomic absorption spectrometry. Risk of a subsequent diagnosis of cancer was positively associated with serum copper levels, but only among those cases diagnosed within 4 years of the time the serum specimens were collected. Among cases diagnosed more than 4 years after specimen collection, there was no consistent association between serum copper levels and risk. Adjustment for age, sex, race, occupational status, cigarette smoking, family history of cancer, alcohol consumption, and, among females, use of exogenous hormones had no appreciable effect on these relationships. The findings suggest that the presence of cancer may increase serum copper levels several years prior to its diagnosis. They are less supportive of the hypothesis that serum copper levels affect cancer risk.

Single crystalline electronic structure and growth mechanism of aligned square graphene sheets

NASA Astrophysics Data System (ADS)

Yang, H. F.; Chen, C.; Wang, H.; Liu, Z. K.; Zhang, T.; Peng, H.; Schröter, N. B. M.; Ekahana, S. A.; Jiang, J.; Yang, L. X.; Kandyba, V.; Barinov, A.; Chen, C. Y.; Avila, J.; Asensio, M. C.; Peng, H. L.; Liu, Z. F.; Chen, Y. L.

2018-03-01

Recently, commercially available copper foil has become an efficient and inexpensive catalytic substrate for scalable growth of large-area graphene films for fundamental research and applications. Interestingly, despite its hexagonal honeycomb lattice, graphene can be grown into large aligned square-shaped sheets on copper foils. Here, by applying angle-resolved photoemission spectroscopy with submicron spatial resolution (micro-ARPES) to study the three-dimensional electronic structures of square graphene sheets grown on copper foils, we verified the high quality of individual square graphene sheets as well as their merged regions (with aligned orientation). Furthermore, by simultaneously measuring the graphene sheets and their substrate copper foil, we not only established the (001) copper surface structure but also discovered that the square graphene sheets' sides align with the ⟨110⟩ copper direction, suggesting an important role of copper substrate in the growth of square graphene sheets—which will help the development of effective methods to synthesize high-quality large-size regularly shaped graphene sheets for future applications. This work also demonstrates the effectiveness of micro-ARPES in exploring low-dimensional materials down to atomic thickness and sub-micron lateral size (e.g., besides graphene, it can also be applied to transition metal dichalcogenides and various van der Waals heterostructures)

Fabrication of flower-like micro/nano dual scale structured copper oxide surfaces: Optimization of self-cleaning properties via Taguchi design

NASA Astrophysics Data System (ADS)

Moosavi, Saeideh Sadat; Norouzbeigi, Reza; Velayi, Elmira

2017-11-01

In the present work, copper oxide superhydrophobic surface is fabricated on a copper foil via the chemical bath deposition (CBD) method. The effects of some influential factors such as initial concentrations of Cu (II) ions and the surface energy modifier, solution pH, reaction and modification steps time on the wettability property of copper oxide surface were evaluated using Taguchi L16 experimental design. Results showed that the initial concentration of Cu (II) has the most significant impact on the water contact angle and wettability characteristics. The XRD, SEM, AFM and FTIR analyses were used to characterize the copper oxide surfaces. The Water contact angle (WCA) and contact angle hysteresis (CAH) were also measured. The SEM results indicated the formation of a flower-like micro/nano dual-scale structure of copper oxide on the substrate. This structure composed of numerous nano-petals with a thickness of about 50 nm. As a result, a copper oxide hierarchical surface with WCA of 168.4°± 3.5° and CAH of 2.73° exhibited the best superhydrophobicity under proposed optimum condition. This result has been obtained just by 10 min hydrolysis reaction. Besides, this surface showed a good stability under acidic and saline conditions.

Uptake and toxicity of arsenic, copper, and silicon in Azolla caroliniana and Lemna minor.

PubMed

Rofkar, Jordan R; Dwyer, Daryl F; Bobak, Deanna M

2014-01-01

Here we report on the analysis of two aquatic plant species, Azolla caroliniana and Lemna minor, with respect to tolerance and uptake of co-occurring arsenic, copper, and silicon for use in engineered wetlands. Plants were cultured in nutrient solution that was amended with arsenic (0 or 20 microM), copper (2 or 78 microM), and silicon (0 or 1.8 mM) either singly or in combination. We hypothesized that arsenic and copper would negatively affect the uptake of metals, growth, and pigmentation and that silicon would mitigate those stresses. Tolerance was assessed by measuring growth of biomass and concentrations of chlorophyll and anthocyanins. Both plant species accumulated arsenic, copper, and silicon; L. minor generally had higher levels on a per biomass basis. Arsenic negatively impacted A. caroliniana, causing a 30% decrease in biomass production and an increase in the concentration of anthocyanin. Copper negatively impacted L. minor, causing a 60% decrease in biomass production and a 45% decrease in chlorophyll content. Silicon augmented the impact of arsenic on biomass production in A. caroliniana but mitigated the effect of copper on L. minor. Our results suggest that mixtures of plant species may be needed to maximize uptake of multiple contaminants in engineered wetlands.

Paradoxical effects of density on measurement of copper tolerance in Silene paradoxa L.

PubMed

Capuana, Maurizio; Colzi, Ilaria; Buccianti, Antonella; Coppi, Andrea; Palm, Emily; Del Bubba, Massimo; Gonnelli, Cristina

2018-01-01

This work investigated if the assessment of tolerance to trace metals can depend on plant density in the experimental design. A non-metallicolous and a metallicolous populations of Silene paradoxa were hydroponically cultivated at increasing density and in both the absence (-Cu conditions) and excess of copper (+Cu conditions). In -Cu conditions, the metallicolous population showed a lower susceptibility to plant density in comparison to the non-metallicolous one, explained by a higher capacity of the metallicolous population to exploit resources. In +Cu conditions, an alleviating effect of increasing density was found in roots. Such effect was present to a greater extent in the non-metallicolous population, thus making the populations equally copper-tolerant at the highest density used. In shoots, an additive effect of increasing plant density to copper toxicity was reported. Its higher intensity in the metallicolous population reverted the copper tolerance relationship at the highest plant densities used. In both populations, a density-induced decrease in root copper accumulation was observed, thus concurring to the reported mitigation in +Cu conditions. Our work revealed the importance of density studies on the optimization of eco-toxicological bioassays and of metal tolerance assessment and it can be considered the first example of an alleviating effect of increasing plant number on copper stress in a metallophyte.

Longitudinal Gradient Dipole Magnet Prototype for APS at ANL

DOE PAGES

Kashikhin, V. S.; Borland, M.; Chlachidze, G.; ...

2016-01-26

We planned an upgrade of the Advanced Photon Source at Argonne National Laboratory (ANL). The main goal of the upgrade is to improve the storage ring performance based on more advanced optics. One of the key magnet system elements is bending dipole magnets having a field strength change along the electron beam path. Moreover, a prototype of one such longitudinal gradient dipole magnet has been designed, built, and measured in a collaborative effort of ANL and Fermilab. Our paper discusses various magnetic design options, the selected magnet design, and the fabrication technology. The prototype magnet has been measured by rotationalmore » coils, a stretched wire, and a Hall probe. Measurement results are discussed and compared with simulations.« less

Is a high serum copper concentration a risk factor for implantation failure?

PubMed

Matsubayashi, Hidehiko; Kitaya, Kotaro; Yamaguchi, Kohei; Nishiyama, Rie; Takaya, Yukiko; Ishikawa, Tomomoto

2017-08-10

Copper-containing contraceptive devices may deposit copper ions in the endometrium, resulting in implantation failure. The deposition of copper ions in many organs has been reported in patients with untreated Wilson's disease. Since these patients sometimes exhibit subfertility and/or early pregnancy loss, copper ions were also considered to accumulate in the uterine endometrium. Wilson's disease patients treated with zinc successfully delivered babies because zinc interfered with the absorption of copper from the gastrointestinal tract. These findings led to the hypothesis that infertile patients with high serum copper concentrations may have implantation failure due to the excess accumulation of copper ions. The relationship between implantation (pregnancy) rates and serum copper concentrations has not yet been examined. The Japanese government recently stated that actual copper intake was higher among Japanese than needed. Therefore, the aim of the present study was to investigate whether serum copper concentrations are related to the implantation (pregnancy) rates of human embryos in vivo. We included 269 patients (age <40 years old) who underwent vitrifying and warming single embryo transfer with a hormone replacement cycle using good blastocysts (3BB or more with Gardner's classification). Serum hCG, copper, and zinc concentrations were measured 16 days after the first date of progesterone replacement. We compared 96 women who were pregnant without miscarriage at 10 weeks of gestation (group P) and 173 women who were not pregnant (group NP). No significant differences were observed in age or BMI between the groups. Copper concentrations were significantly higher in group NP (average 193.2 μg/dL) than in group P (average 178.1 μg/dL). According to the area under the curve (AUC) on the receiver operating characteristic curve for the prediction of clinical pregnancy rates, the Cu/Zn ratio (AUC 0.64, 95% CI 0.54-0.71) was a better predictor than copper or zinc. When we set the cut-off as 1.59/1.60 for the Cu/Zn ratio, sensitivity, specificity, the positive predictive value, and negative predictive value were 0.98, 0.29, 0.71, and 0.88, respectively. Our single-center retrospective study suggests that high serum copper concentrations (high Cu/Zn ratio) are a risk factor for implantation failure.

Micromachined lab-on-a-tube sensors for simultaneous brain temperature and cerebral blood flow measurements.

PubMed

Li, Chunyan; Wu, Pei-Ming; Hartings, Jed A; Wu, Zhizhen; Cheyuo, Cletus; Wang, Ping; LeDoux, David; Shutter, Lori A; Ramaswamy, Bharat Ram; Ahn, Chong H; Narayan, Raj K

2012-08-01

This work describes the development of a micromachined lab-on-a-tube device for simultaneous measurement of brain temperature and regional cerebral blood flow. The device consists of two micromachined gold resistance temperature detectors with a 4-wire configuration. One is used as a temperature sensor and the other as a flow sensor. The temperature sensor operates with AC excitation current of 500 μA and updates its outputs at a rate of 5 Hz. The flow sensor employs a periodic heating and cooling technique under constant-temperature mode and updates its outputs at a rate of 0.1 Hz. The temperature sensor is also used to compensate for temperature changes during the heating period of the flow sensor to improve the accuracy of flow measurements. To prevent thermal and electronic crosstalk between the sensors, the temperature sensor is located outside the "thermal influence" region of the flow sensor and the sensors are separated into two different layers with a thin-film Copper shield. We evaluated the sensors for accuracy, crosstalk and long-term drift in human blood-stained cerebrospinal fluid. These in vitro experiments showed that simultaneous temperature and flow measurements with a single lab-on-a-tube device are accurate and reliable over the course of 5 days. It has a resolution of 0.013 °C and 0.18 ml/100 g/min; and achieves an accuracy of 0.1 °C and 5 ml/100 g/min for temperature and flow sensors respectively. The prototype device and techniques developed here establish a foundation for a multi-sensor lab-on-a-tube, enabling versatile multimodality monitoring applications.

Validation of a station-prototype designed to integrate temporally soil N2O fluxes: IPNOA Station prototype.

NASA Astrophysics Data System (ADS)

Laville, Patricia; Volpi, Iride; Bosco, Simona; Virgili, Giorgio; Neri, Simone; Continanza, Davide; Bonari, Enrico

2016-04-01

Nitrous oxide (N2O) flux measurements from agricultural soil surface still accounts for the scientific community as major challenge. The evaluations of integrated soil N2O fluxes are difficult because these emissions are lower than for the other greenhouse gases sources (CO2, CH4). They are also sporadic, because highly dependent on few environmental conditions acting as limiting factors. Within a LIFE project (IPNOA: LIFE11 ENV/IT/00032) a station prototype was developed to integrate annually N2O and CO2 emissions using automatically chamber technique. Main challenge was to develop a device enough durable to be able of measuring in continuous way CO2 and N2O fluxes with sufficient sensitivity to allow make reliable assessments of soil GHG measurements with minimal technical field interventions. The IPNOA station prototype was developed by West System SRL and was set up during 2 years (2014 -2015) in an experimental maize field in Tuscan. The prototype involved six automatic chambers; the complete measurement cycle was of 2 hours. Each chamber was closing during 20 min and biogas accumulations were monitoring in line with IR spectrometers. Auxiliary's measurements including soil temperatures and water contents as weather data were also monitoring. All data were managed remotely with the same acquisition software installed in the prototype control unit. The operation of the prototype during the two cropping years allowed testing its major features: its ability to evaluate the temporal variation of N2O soil fluxes during a long period with weather conditions and agricultural managements and to prove the interest to have continuous measurements of fluxes. The temporal distribution of N2O fluxes indicated that emissions can be very large and discontinuous over short periods less ten days and that during about 70% of the time N2O fluxes were around detection limit of the instrumentation, evaluated to 2 ng N ha-1 day-1. N2O emission factor assessments were 1.9% in 2014 and 1.7 % in 2015, in the range of IPCC ones. The instrumentation was working almost permanently during these two years. The proximity sensors fitted on the chambers allowed showing that the chambers were functioning normally for about 90% of the time. A cross-comparison carried out in September 2015 with the "mobile IPNOA prototype"; a high-sensibility transportable instrument (previously validated), allowed showing a good agreement between the 2 instrumentations.

Copper intrauterine device for emergency contraception: clinical practice among contraceptive providers.

PubMed

Harper, Cynthia C; Speidel, J Joseph; Drey, Eleanor A; Trussell, James; Blum, Maya; Darney, Philip D

2012-02-01

The copper intrauterine device (IUD) is the most effective emergency contraceptive available but is largely ignored in clinical practice. We examined clinicians' recommendations of the copper IUD for emergency contraception in a setting with few cost obstacles. We conducted a survey among clinicians (n=1,246; response rate 65%) in a California State family planning program, where U.S. Food and Drug Administration-approved contraceptives are available at no cost to low-income women. We used multivariable logistic regression to measure the association of intrauterine contraceptive training and evidence-based knowledge with having recommended the copper IUD for emergency contraception. The large majority of clinicians (85%) never recommended the copper IUD for emergency contraception, and most (93%) required two or more visits for an IUD insertion. Multivariable analyses showed insertion skills were associated with having recommended the copper IUD for emergency contraception, but the most significant factor was evidence-based knowledge of patient selection for IUD use. Clinicians who viewed a wide range of patients as IUD candidates were twice as likely to have recommended the copper IUD for emergency contraception. Although more than 93% of obstetrician-gynecologists were skilled in inserting the copper IUD, they were no more likely to have recommended it for emergency contraception than other physicians or advance practice clinicians. Recommendation of the copper IUD for emergency contraception is rare, despite its high efficacy and long-lasting contraceptive benefits. Recommendation would require clinic flow and scheduling adjustments to allow same-day IUD insertions. Patient-centered and high-quality care for emergency contraception should include a discussion of the most effective method. III.

Chronic toxicity of copper on embryo development in Chinese toad, Bufo gargarizans.

PubMed

Xia, Kun; Zhao, Hongfeng; Wu, Minyao; Wang, Hongyuan

2012-06-01

This study examined the effects of copper exposure on embryonic development of Chinese toad, Bufo gargarizans. Firstly, the LC(50) values from 24 to 96 h of exposure were 3.61×10(-6) M, by means of a 4 d toxicity test with B. gargarizans embryos. Secondly, Chinese toad embryos were exposed to 10(-9)-10(-6) M copper from mid gastrula stage to operculum completion stage. Measurements included mortality, tadpole weight, tadpole total length, growth retardation, duration of different embryo stages and malformation. Embryonic survival was not affected by copper. Relative to control tadpoles, significantly decreased weight and total length were found at 10(-9)-10(-6) M reduced percentage of the embryos in right operculum stage after 10 d exposure to copper and reduced percentage of embryos in operculum completion stage after 12 d exposure to copper were also observed. Moreover, the duration of embryonic development increased at neural, circulation and operculum development stage in copper-treated groups. For the scanning microscope and histological observation, the abnormalities were malformation of wavy dorsal fin, flexural tail, curvature body axis, yolk sac oedema and reduced pigmentation in the yolk sac. Histopathological changes in olfactory, retinal epithelium and skin were also observed. DNA strand breaks exposed to the copper were analyzed by DNA ladder. In conclusion, copper induced toxic effects on B. gargarizans embryos. The present study indicated chronic toxicity tests may provide more accurate way in formulating the "safe levels" of heavy metals to amphibian. Copyright © 2012 Elsevier Ltd. All rights reserved.

Standard state thermodynamic properties of Ba2+(aq), Co2+(aq), and Cu2+(aq) up to 598.15 K, and temperature effect on ligand field.

PubMed

Djamali, Essmaiil; Chen, Keith; Murray, Richard C; Turner, Peter J; Cobble, James W

2009-02-26

Integral heat of solution measurements of barium chloride to 619.81 K, copper oxide in an excess of perrhenic acid to 585 K, and cobalt perrhenate in perrhenic acid to 573 K were measured in a high dilution calorimeter (< or =10(-3) m) at psat, from which the high temperature thermodynamic properties of aqueous barium chloride, copper perrhenate, and cobalt perrhenate were obtained. From the known differences between the corresponding properties for aqueous perrhenate and chloride ions, the thermodynamic properties of completely ionized aqueous copper and cobalt chloride were obtained from ionic additivity. The enthalpy and derived heat capacity data at higher temperatures (T > 473.15 K) suggest that the ligand field stabilization energy of Co2+(aq) may be disappearing.

Local density measurement of additive manufactured copper parts by instrumented indentation

NASA Astrophysics Data System (ADS)

Santo, Loredana; Quadrini, Fabrizio; Bellisario, Denise; Tedde, Giovanni Matteo; Zarcone, Mariano; Di Domenico, Gildo; D'Angelo, Pierpaolo; Corona, Diego

2018-05-01

Instrumented flat indentation has been used to evaluate local density of additive manufactured (AM) copper samples with different relative density. Indentations were made by using tungsten carbide (WC) flat pins with 1 mm diameter. Pure copper powders were used in a selective laser melting (SLM) machine to produce samples to test. By changing process parameters, samples density was changed from the relative density of 63% to 71%. Indentation tests were performed on the xy surface of the AM samples. In order to make a correlation between indentation test results and sample density, the indentation pressure at fixed displacement was selected. Results show that instrumented indentation is a valid technique to measure density distribution along the geometry of an SLM part. In fact, a linear trend between indentation pressure and sample density was found for the selected density range.

Design and first plasma measurements of the ITER-ECE prototype radiometer

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

Austin, M. E.; Brookman, M. W.; Rowan, W. L.

2016-11-15

On ITER, second harmonic optically thick electron cyclotron emission (ECE) in the range of 220-340 GHz will supply the electron temperature (T{sub e}). To investigate the requirements and capabilities prescribed for the ITER system, a prototype radiometer covering this frequency range has been developed by Virginia Diodes, Inc. The first plasma measurements with this instrument have been carried out on the DIII-D tokamak, with lab bench tests and measurements of third through fifth harmonic ECE from high T{sub e} plasmas. At DIII-D the instrument shares the transmission line of the Michelson interferometer and can simultaneously acquire data. Comparison of themore » ECE radiation temperature from the absolutely calibrated Michelson and the prototype receiver shows that the ITER radiometer provides accurate measurements of the millimeter radiation across the instrument band.« less

Heavy metal concentrations in plants growing on a copper mine spoil in the Grand Canyon, Arizona. [Thlaspi montanum; Phlox austromontana; Juniperus osteosperma

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

Hobbs, R.J.; Streit, B.

1986-05-01

Concentrations of metals including manganese, nickel, copper and zinc were measured in soil from a copper mine spoil heap in the Grand Canyon, Arizona, and in three plant species growing on the spoil. The soil had high concentrations of available copper and zinc, and the herbaceous perennial Thlaspi montanum var fendleri contained amounts of Ni, Cu and Zn in direct proportion to the soil concentrations (EDTA extractable). Another herbaceous perennial, Phlox austromontana, and the woody perennial Juniperus osteosperma had considerably lower amounts of these elements. These findings are discussed in relation to other studies, and it is suggested that figuresmore » for metal accumulation by plants should always be related to plant-available soil concentrations.« less

Unsupported single-atom-thick copper oxide monolayers

NASA Astrophysics Data System (ADS)

Yin, Kuibo; Zhang, Yu-Yang; Zhou, Yilong; Sun, Litao; Chisholm, Matthew F.; Pantelides, Sokrates T.; Zhou, Wu

2017-03-01

Oxide monolayers may present unique opportunities because of the great diversity of properties of these materials in bulk form. However, reports on oxide monolayers are still limited. Here we report the formation of single-atom-thick copper oxide layers with a square lattice both in graphene pores and on graphene substrates using aberration-corrected scanning transmission electron microscopy. First-principles calculations find that CuO is energetically stable and its calculated lattice spacing matches well with the measured value. Furthermore, free-standing copper oxide monolayers are predicted to be semiconductors with band gaps ˜3 eV. The new wide-bandgap single-atom-thick copper oxide monolayers usher a new frontier to study the highly diverse family of two-dimensional oxides and explore their properties and their potential for new applications.

Preparation and characterization of copper telluride thin films by modified chemical bath deposition (M-CBD) method

NASA Astrophysics Data System (ADS)

Pathan, H. M.; Lokhande, C. D.; Amalnerkar, D. P.; Seth, T.

2003-09-01

Copper telluride thin films were deposited using modified chemical method using copper(II) sulphate; pentahydrate [CuSO 4·5H 2O] and sodium tellurite [Na 2TeO 3] as cationic and anionic sources, respectively. Modified chemical method is based on the immersion of the substrate into separately placed cationic and anionic precursors. The preparative conditions such as concentration, pH, immersion time, immersion cycles, etc. were optimized to get good quality copper telluride thin films at room temperature. The films have been characterized for structural, compositional, optical and electrical transport properties by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), Rutherford back scattering (RBS), optical absorption/transmission, electrical resistivity and thermoemf measurement techniques.

Friction, wear, and transfer of carbon and graphite to copper, chromium, and aluminum metal surfaces in vacuum

NASA Technical Reports Server (NTRS)

Buckley, D. H.

1973-01-01

Sliding friction experiments were conducted with amorphous and fully graphitized carbons sliding on copper and on films of chromium and aluminum on copper. Auger emission spectroscopy analysis was used to monitor carbon transfer to the metal surfaces. Friction and wear were also measured. Metal surfaces were examined both in the clean state and with normal oxides present. Results indicate that different metals have an important effect on friction, wear, and transfer characteristics. With amorphous carbon, the least chemically active metal gave the highest wear and amount of carbon transfer. Both forms of carbon gave lower friction and wear and lower transfer rates when in contact with clean, as opposed to oxide-covered, chromium surfaces. With copper, the reverse was true; cleaning was detrimental.

A Nano-Thin Film-Based Prototype QCM Sensor Array for Monitoring Human Breath and Respiratory Patterns.

PubMed

Selyanchyn, Roman; Wakamatsu, Shunichi; Hayashi, Kenshi; Lee, Seung-Woo

2015-07-31

Quartz crystal microbalance (QCM) sensor array was developed for multi-purpose human respiration assessment. The sensor system was designed to provide feedback for human respiration. Thorough optimization of measurement conditions: air flow, temperature in the QCM chamber, frequency measurement rate, and electrode position regarding to the gas flow-was performed. As shown, acquisition of respiratory parameters (rate and respiratory pattern) could be achieved even with a single electrode used in the system. The prototype system contains eight available QCM channels that can be potentially used for selective responses to certain breath chemicals. At present, the prototype machine is ready for the assessment of respiratory functions in larger populations in order to gain statistical validation. To the best of our knowledge, the developed prototype is the only respiratory assessment system based on surface modified QCM sensors.

Post examination of copper ER sensors exposed to bentonite

NASA Astrophysics Data System (ADS)

Kosec, Tadeja; Kranjc, Andrej; Rosborg, Bo; Legat, Andraž

2015-04-01

Copper corrosion in saline solutions under oxic conditions is one of concerns for the early periods of disposal of spent nuclear fuel in deep geological repositories. The main aim of the study was to investigate the corrosion behaviour of copper during this oxic period. The corrosion rate of pure copper was measured by means of thin electrical resistance (ER) sensors that were placed in a test package containing an oxic bentonite/saline groundwater environment at room temperature for a period of four years. Additionally, the corrosion rate was monitored by electrochemical impedance spectroscopy (EIS) measurements that were performed on the same ER sensors. By the end of the exposure period the corrosion rate, as estimated by both methods, had dropped to approximately 1.0 μm/year. The corrosion rate was also estimated by the examination of metallographic cross sections. The post examination tests which were used to determine the type and extent of corrosion products included different spectroscopic techniques (XRD and Raman analysis). It was confirmed that the corrosion rate obtained by means of physical (ER) and electrochemical techniques (EIS) was consistent with that estimated from the metallographic cross section analysis. The corrosion products consisted of cuprous oxide and paratacamite, which was very abundant. From the types of attack it can be concluded that the investigated samples of copper in bentonite underwent uneven general corrosion.

EVALUATION OF THE EFFECTIVENESS OF COATINGS IN REDUCING DISLODGEABLE ARSENIC, CHROMIUM, AND COPPER FROM CCA TREATED WOOD, INTERIM DATA REPORT

EPA Science Inventory

EPA is approximately 20 months into a project to evaluate the performance of wood coatings as a way to prevent arsenic, chromium and copper exposure from the surfaces of CCA treated wood. Potential dermal exposure, as measured by wipe sampling dislodgeable CCA chemical from wood ...

Estimating preservative release from treated wood exposed to precipitation

Treesearch

Stan Lebow; Patricia Lebow; Daniel Foster

2008-01-01

Accelerated leaching methods are needed to better estimate emissions from treated wood used above ground or above water. In this study, we evaluated leaching methods using continuous immersion, dip immersion, and simulated rainfall approaches. Copper and/or boron emissions were measured for specimens treated with either chromated copper arsenate Type C (CCA-C) or a...

Life cycle contributions of copper from vessel painting and maintenance activities

PubMed Central

Earley, Patrick J.; Swope, Brandon L.; Barbeau, Katherine; Bundy, Randelle; McDonald, Janessa A.; Rivera-Duarte, Ignacio

2013-01-01

Copper-based epoxy and ablative antifouling painted panels were exposed in natural seawater to evaluate environmental loading parameters. In situ loading factors including initial exposure, passive leaching, and surface refreshment were measured utilizing two protocols developed by the US Navy: the dome method and the in-water hull cleaning sampling method. Cleaning techniques investigated included a soft-pile carpet and a medium duty 3M™ pad for fouling removal. Results show that the passive leach rates of copper peaked three days after both initial deployment and cleaning events (CEs), followed by a rapid decrease over about 15 days and a slow approach to asymptotic levels on approximately day 30. Additionally, copper was more bioavailable during a CE in comparison to the passive leaching that immediately followed. A paint life cycle model quantifying annual copper loading estimates for each paint and cleaning method based on a three-year cycle of painting, episodic cleaning, and passive leaching is presented. PMID:24199998

Conductivity of laser printed copper structures limited by nano-crystal grain size and amorphous metal droplet shell

NASA Astrophysics Data System (ADS)

Winter, Shoshana; Zenou, Michael; Kotler, Zvi

2016-04-01

We present a study of the morphology and electrical properties of copper structures which are printed by laser induced forward transfer from bulk copper. The percentage of voids and the oxidation levels are too low to account for the high resistivities (~4 to 14 times the resistivity of bulk monocrystalline copper) of these structures. Transmission electron microscope (TEM) images of slices cut from the printed areas using a focused ion beam (FIB) show nano-sized crystal structures with grain sizes that are smaller than the electron free path length. Scattering from such grain boundaries causes a significant increase in the resistivity and can explain the measured resistivities of the structures. The TEM images also show a nano-amorphous layer (~5 nm) at the droplet boundaries which also contributes to the overall resistivity. Such morphological characteristics are best explained by the ultrafast cooling rate of the molten copper droplets during printing.

Evidence for the role of copper in the injury process of coliform bacteria in drinking water. [Escherichia coli

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

Domek, M.J.; LeChevallier, M.W.; Cameron, S.C.

1984-08-01

Low levels of copper in chlorine-free distribution water caused injury of coliform populations. Monitoring of 44 drinking water samples indicated that 64% of the coliform population was injured. Physical and chemical parameters were measured, including three heavy metals (Cu, Cd, and Pb). Copper concentrations were important, ranging from 0.007 to 0.54 mg/liter. Statistical analyses of these factors were used to develop a model to predict coliform injury. The model predicted almost 90% injury with a copper concentration near the mean observed value (0.158 mg/liter) in distribution waters. Laboratory studies with copper concentrations of 0.025 and 0.050 mg/liter in an inorganicmore » carbon buffer under controlled conditions of temperature and pH caused over 90% injury within 6 and 2 days, respectively. Studies of the metabolism of injured Escherichia coli cells indicated that the respiratory chain is at least one site of damage in injured cells.« less

Annealing effects in plated-wire memory elements. I - Interdiffusion of copper and Permalloy.

NASA Technical Reports Server (NTRS)

Knudson, C. I.; Kench, J. R.

1971-01-01

Results of investigations using X-ray diffraction and electron-beam microprobe techniques have shown that copper and Permalloy platings interdiffuse at low temperatures when plated-wire memory elements are annealed for times as short as 50 hr. Measurable interdiffusion between Permalloy platings and gold substrates does not occur in similar conditions. Both magnetic and compositional changes during aging are found to occur by a thermally activated process with activation energies around 38 kcal/mol. It is shown, however, that copper-diffusion and magnetic-dispersion changes during aging are merely concurrent processes, neither being the other's cause.

Generation of metallic plasmon nanostructures in a thin transparent photosensitive copper oxide film by femtosecond thermochemical decomposition

NASA Astrophysics Data System (ADS)

Danilov, P. A.; Zayarny, D. A.; Ionin, A. A.; Kudryashov, S. I.; Litovko, E. P.; Mel'nik, N. N.; Rudenko, A. A.; Saraeva, I. N.; Umanskaya, S. P.; Khmelnitskii, R. A.

2017-09-01

Irradiation of optically transparent copper (I) oxide film covering a glass substrate with a tightly focused femtosecond laser pulses in the pre-ablation regime leads to film reduction to a metallic colloidal state via a single-photon absorption and its subsequent thermochemical decomposition. This effect was demonstrated by the corresponding measurement of the extinction spectrum in visible spectral range. The laser-induced formation of metallic copper nanoparticles in the focal region inside the bulk oxide film allows direct recording of individual thin-film plasmon nanostructures and optical-range metasurfaces.

Fully gapped superconductivity with no sign change in the prototypical heavy-fermion CeCu2Si2

PubMed Central

Yamashita, Takuya; Takenaka, Takaaki; Tokiwa, Yoshifumi; Wilcox, Joseph A.; Mizukami, Yuta; Terazawa, Daiki; Kasahara, Yuichi; Kittaka, Shunichiro; Sakakibara, Toshiro; Konczykowski, Marcin; Seiro, Silvia; Jeevan, Hirale S.; Geibel, Christoph; Putzke, Carsten; Onishi, Takafumi; Ikeda, Hiroaki; Carrington, Antony; Shibauchi, Takasada; Matsuda, Yuji

2017-01-01

In exotic superconductors, including high-Tc copper oxides, the interactions mediating electron Cooper pairing are widely considered to have a magnetic rather than a conventional electron-phonon origin. Interest in this exotic pairing was initiated by the 1979 discovery of heavy-fermion superconductivity in CeCu2Si2, which exhibits strong antiferromagnetic fluctuations. A hallmark of unconventional pairing by anisotropic repulsive interactions is that the superconducting energy gap changes sign as a function of the electron momentum, often leading to nodes where the gap goes to zero. We report low-temperature specific heat, thermal conductivity, and magnetic penetration depth measurements in CeCu2Si2, demonstrating the absence of gap nodes at any point on the Fermi surface. Moreover, electron irradiation experiments reveal that the superconductivity survives even when the electron mean free path becomes substantially shorter than the superconducting coherence length. This indicates that superconductivity is robust against impurities, implying that there is no sign change in the gap function. These results show that, contrary to long-standing belief, heavy electrons with extremely strong Coulomb repulsions can condense into a fully gapped s-wave superconducting state, which has an on-site attractive pairing interaction. PMID:28691082

Experimental Characterization of Cryogenic Helium Pulsating Heat Pipes

NASA Astrophysics Data System (ADS)

Fonseca Flores, Luis Diego

This study was inspired to investigate an alternative cooling system using a helium-based pulsating heat pipes (PHP), for low temperature superconducting magnets in MRI systems. In addition, the same approach can be used for exploring other low temperature applications such as cooling space instrumentation. The advantages of PHP for transferring heat and smoothing temperature profiles in various room temperature applications have been explored for the past 20 years. An experimental apparatus has been designed, fabricated and operated and is primarily composed of an evaporator and a condenser; in which both are thermally connected by a closed loop capillary tubing. The main goal is to measure the heat transfer properties of this device using helium as the working fluid. The evaporator end of the PHP is comprised of a copper winding in which heat loads up to 10 watts are generated, while the condenser is isothermal and can reach 4.2 K at 1 W via a two stage Sumitomo RDK408A2 GM cryocooler. Various experimental design features are highlighted. Additionally, the thermal performance for the presented design remained unchanged when increasing the adiabatic length from 300 mm to 1000 mm. Finally a spring mass damper model has been developed and proven to predict well the experimental data, such models should be used as tool to design and manufacturer PHP prototypes.

Summary Scientific Performance of EUCLID Detector Prototypes

NASA Technical Reports Server (NTRS)

Rauscher, Bernard J.

2011-01-01

NASA and the European Space Agency (ESA) plan to partner to build the EUCLID mission. EUCLID is a mission concept for studying the Dark Energy that is hypothesized to account for the accelerating cosmic expansion. For the past year, NASA has been building detector prototypes at Teledyne Imaging Sensors. This talk will summarize the measured scientific performance of these detector prototypes for astrophysical and cosmological applications.

Copper-resistant halophilic bacterium isolated from the polluted Maruit Lake, Egypt.

PubMed

Osman, O; Tanguichi, H; Ikeda, K; Park, P; Tanabe-Hosoi, S; Nagata, S

2010-04-01

To isolate and characterize copper-resistant halophilic bacteria from the polluted Maruit Lake, Egypt and identify the role of plasmids in toxic metal resistance. We isolated strain MA2, showing high copper resistance up to the 1.5 mmol l(-1) concentration; it was also resistant to other metals such as nickel, cobalt and zinc and a group of antibiotics. Partial 16S rRNA analysis revealed that strain MA2 belonged to the genus Halomonas. Copper uptake, measured by atomic absorption spectrophotometery, was higher in the absence of NaCl than in the presence of 0.5-1.0 mol l(-1) NaCl during 5-15 min of incubation. Cell fractionation and electron microscopic observation clarified that most of the copper accumulated in the outer membrane and periplasmic fractions of the cells. Plasmid screening yielded two plasmids: pMA21 (11 kb) and pMA22 (5 kb). Plasmid curing resulted in a strain that lost both the plasmids and was sensitive to cobalt and chromate but not copper, nickel and zinc. This cured strain also showed weak growth in the presence of 0.5-1.0 mol l(-1) NaCl. Partial sequencing of both plasmids led to the identification of different toxic metals transporters but copper transporters were not identified. The highest cell viability was found in the presence of 1.0 mol l(-1) NaCl at different copper concentrations, and copper uptake was optimal in the absence of NaCl. Plasmid pMA21 encoded chromate, cobalt, zinc and cadmium transporters, whereas pMA22 encoded specific zinc and RND (resistance, nodulation, cell division) efflux transporters as well as different kinds of metabolic enzymes. Copper resistance was mainly incorporated in the chromosome. Strain MA2 is a fast and efficient tool for copper bioremediation and the isolated plasmids show significant characteristics of both toxic metal and antibiotic resistance.

Subneurotoxic copper(II)-induced NF-κB-dependent microglial activation is associated with mitochondrial ROS

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

Hu, Zhuqin; Yu, Fengxiang; Gong, Ping

2014-04-15

Microglia-mediated neuroinflammation and the associated neuronal damage play critical roles in the pathogenesis of neurodegenerative disorders. Evidence shows an elevated concentration of extracellular copper(II) in the brains of these disorders, which may contribute to neuronal death through direct neurotoxicity. Here we explored whether extracellular copper(II) triggers microglial activation. Primary rat microglia and murine microglial cell line BV-2 cells were cultured and treated with copper(II). The content of tumor necrosis factor-α (TNF-α) and nitric oxide in the medium was determined. Extracellular hydrogen peroxide was quantified by a fluorometric assay with Amplex Red. Mitochondrial superoxide was measured by MitoSOX oxidation. At subneurotoxicmore » concentrations, copper(II) treatment induced a dose- and time-dependent release of TNF-α and nitric oxide from microglial cells, and caused an indirect, microglia-mediated neurotoxicity that was blocked by inhibition of TNF-α and nitric oxide production. Copper(II)-initiated microglial activation was accompanied with reduced IkB-α expression as well as phosphorylation and translocation of nuclear factor-κB (NF-κB) p65 and was blocked by NF-κB inhibitors (BAY11-7082 and SC-514). Moreover, copper(II) treatment evoked a rapid release of hydrogen peroxide from microglial cells, an effect that was not affected by NADPH oxidase inhibitors. N-acetyl-cysteine, a scavenger of reactive oxygen species (ROS), abrogated copper(II)-elicited microglial release of TNF-α and nitric oxide and subsequent neurotoxicity. Importantly, mitochondrial production of superoxide, paralleled to extracellular release of hydrogen peroxide, was induced after copper(II) stimulation. Our findings suggest that extracellular copper(II) at subneurotoxic concentrations could trigger NF-κB-dependent microglial activation and subsequent neurotoxicity. NADPH oxidase-independent, mitochondria-derived ROS may be involved in this activation. - Highlights: • Subneurotoxic copper(II) triggers NF-κB-dependent microglial activation. • This activation leads to hippocampal neuronal death. • This activation may involve mitochondria-derived reactive oxygen species.« less

Corrosion of copper in oxygen-deficient groundwater with and without deep bedrock micro-organisms: Characterisation of microbial communities and surface processes

NASA Astrophysics Data System (ADS)

Huttunen-Saarivirta, E.; Rajala, P.; Bomberg, M.; Carpén, L.

2017-02-01

Copper specimens were exposed to oxygen-deficient artificial groundwater in the presence and absence of micro-organisms enriched from the deep bedrock of the planned nuclear waste repository site at Olkiluoto island on the western coast of Finland. During the exposure periods of 4 and 10 months, the copper specimens were subjected to electrochemical measurements. The biofilm developed on the specimens and the water used in the exposures were subjected to microbiological analyses. Changes in the water chemistry were also determined and surfaces of the copper specimens were characterized with respect to the morphology and composition of the formed corrosion products. The results showed that under biotic conditions, redox of the water and open circuit potential (OCP) of the copper specimens were generally negative and resulted in the build-up of a copper sulphide, Cu2S, layer due to the activity of sulphate-reducing bacteria (SRB) that were included in the system. In the 4-month test, the electrochemical behaviour of the specimens changed during the exposure and alphaproteobactria Rhizobiales were the dominant bacterial group in the biofilm where the highest corrosion rate was observed. In the 10-month test, however, deltaproteobacteria SRB flourished and the initial electrochemical behaviour and the low corrosion rate of the copper were retained until the end of the test period. Under abiotic conditions, the positive water redox potential and specimen OCP correlated with the formation of copper oxide, Cu2O. Furthermore, in the absence of SRB, Cu2O provided slightly inferior protection against corrosion compared to that by Cu2S in the presence of SRB. The obtained results show that the presence of microorganisms may enhance the passivity of copper. In addition, the identification of key microbial species, such as SRB thriving on copper for long time periods, is important for successful prediction of the behaviour of copper.

Pre-diagnostic copper and zinc biomarkers and colorectal cancer risk in the European Prospective Investigation into Cancer and Nutrition cohort.

PubMed

Stepien, Magdalena; Jenab, Mazda; Freisling, Heinz; Becker, Niels-Peter; Czuban, Magdalena; Tjønneland, Anne; Olsen, Anja; Overvad, Kim; Boutron-Ruault, Marie-Christine; Mancini, Francesca Romana; Savoye, Isabelle; Katzke, Verena; Kühn, Tilman; Boeing, Heiner; Iqbal, Khalid; Trichopoulou, Antonia; Bamia, Christina; Orfanos, Philippos; Palli, Domenico; Sieri, Sabina; Tumino, Rosario; Naccarati, Alessio; Panico, Salvatore; Bueno-de-Mesquita, H B As; Peeters, Petra H; Weiderpass, Elisabete; Merino, Susana; Jakszyn, Paula; Sanchez, Maria-Jose; Dorronsoro, Miren; Huerta, José María; Barricarte, Aurelio; Boden, Stina; van Guelpen, Behany; Wareham, Nick; Khaw, Kay-Tee; Bradbury, Kathryn E; Cross, Amanda J; Schomburg, Lutz; Hughes, David J

2017-07-01

Adequate intake of copper and zinc, two essential micronutrients, are important for antioxidant functions. Their imbalance may have implications for development of diseases like colorectal cancer (CRC), where oxidative stress is thought to be etiologically involved. As evidence from prospective epidemiologic studies is lacking, we conducted a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort to investigate the association between circulating levels of copper and zinc, and their calculated ratio, with risk of CRC development. Copper and zinc levels were measured by reflection X-ray fluorescence spectrometer in 966 cases and 966 matched controls. Multivariable adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated using conditional logistic regression and are presented for the fifth versus first quintile. Higher circulating concentration of copper was associated with a raised CRC risk (OR = 1.50; 95% CI: 1.06, 2.13; P-trend = 0.02) whereas an inverse association with cancer risk was observed for higher zinc levels (OR = 0.65; 95% CI: 0.43, 0.97; P-trend = 0.07). Consequently, the ratio of copper/zinc was positively associated with CRC (OR = 1.70; 95% CI: 1.20, 2.40; P-trend = 0.0005). In subgroup analyses by follow-up time, the associations remained statistically significant only in those diagnosed within 2 years of blood collection. In conclusion, these data suggest that copper or copper levels in relation to zinc (copper to zinc ratio) become imbalanced in the process of CRC development. Mechanistic studies into the underlying mechanisms of regulation and action are required to further examine a possible role for higher copper and copper/zinc ratio levels in CRC development and progression. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Radiation induced corrosion of copper for spent nuclear fuel storage

NASA Astrophysics Data System (ADS)

Björkbacka, Åsa; Hosseinpour, Saman; Johnson, Magnus; Leygraf, Christofer; Jonsson, Mats

2013-11-01

The long term safety of repositories for radioactive waste is one of the main concerns for countries utilizing nuclear power. The integrity of engineered and natural barriers in such repositories must be carefully evaluated in order to minimize the release of radionuclides to the biosphere. One of the most developed concepts of long term storage of spent nuclear fuel is the Swedish KBS-3 method. According to this method, the spent fuel will be sealed inside copper canisters surrounded by bentonite clay and placed 500 m down in stable bedrock. Despite the importance of the process of radiation induced corrosion of copper, relatively few studies have been reported. In this work the effect of the total gamma dose on radiation induced corrosion of copper in anoxic pure water has been studied experimentally. Copper samples submerged in water were exposed to a series of total doses using three different dose rates. Unirradiated samples were used as reference samples throughout. The copper surfaces were examined qualitatively using IRAS and XPS and quantitatively using cathodic reduction. The concentration of copper in solution after irradiation was measured using ICP-AES. The influence of aqueous radiation chemistry on the corrosion process was evaluated based on numerical simulations. The experiments show that the dissolution as well as the oxide layer thickness increase upon radiation. Interestingly, the evaluation using numerical simulations indicates that aqueous radiation chemistry is not the only process driving the corrosion of copper in these systems.

Evaluation of Serum Levels of Zinc, Copper, Iron, and Zinc/Copper Ratio in Cutaneous Leishmaniasis

PubMed Central

Pourfallah, F; Javadian, S; Zamani, Z; Saghiri, R; Sadeghi, S; Zarea, B; Faiaz, Sh; Mirkhani, F; Fatemi, N

2009-01-01

Background: The purpose of this study was to evaluate the levels of zinc (Zn), copper (Cu), iron (Fe) and zinc/ copper ratio in the serum of patients with cutaneous leishmaniasis in Qom Province, center of Iran. Methods: Serum levels of zinc and copper were determined by flame atomic absorption spectrophotometer and serum iron concentration was measured by using an Auto Analyzer. The study group consisted of 60 patients with cutaneous leishmaniasis and the control group of 100 healthy volunteers from the same area who were not exposed to cutaneous leishmaniasis. Result: There were no statistically significant differences in age and body mass index between the two groups. Serum Zn (P< 0.001) and Fe (P< 0.05) levels were lower in patients with cutaneous leishmaniasis than the control group. We also found serum Cu concentration (P< 0.05) in the patient group was significantly higher than that of the control group. However, zinc/ copper ratio (P< 0.001) was lower in patients with cutaneous leishmaniasis than in the control group. Conclusion: Our data indicated that Zn/Cu ratio was significantly lower in patients with CL as compared to the controls. Earlier reports suggest that, this ratio imbalance could be a useful marker for immune dysfunction in leishmaniasis. There was also strong association of Zn, Cu and Fe with CL. It suggests the use of blood zinc, copper, iron concentration and the copper/zinc ratio (Zn/Cu), as a means for estimating the prognosis of CL. PMID:22808376

Effects of dissolved organic carbon on the toxicity of copper to the developing embryos of the Pacific oyster (Crassostrea gigas).

PubMed

Brooks, Steven J; Bolam, Thi; Tolhurst, Laura; Bassett, Janice; La Roche, Jay; Waldock, Mike; Barry, Jon; Thomas, Kevin V

2007-08-01

The effects of humic acid (HA) on copper speciation and its subsequent toxicity to the sensitive early life stages of the Pacific oyster (Crassostrea gigas) are presented. Differential pulse anodic stripping voltammetry with a hanging mercury drop electrode was used to measure the copper species as labile copper (LCu; free ion and inorganic copper complexes) and total copper (TCu) with respect to increasing HA concentration. The TCu and LCu 50% effect concentrations (EC50s) in the absence of HA were 20.77 microg/L (95% confidence interval [CI], 24.02-19.97 microg/L) and 8.05 microg/L (95% CI, 9.6-5.92 microg/L) respectively. A corrected dissolved organic carbon (DOC) concentration (HA only) of 1.02 mg/L was required to significantly increase the TCu EC50 to approximately 41.09 microg/L (95% CI, 44.27-37.52 microg/L; p < 0.05), almost doubling that recorded when DOC (as HA) was absent from the test media. In contrast, the LCu EC50 was unaffected by changes in DOC concentration and was stable throughout the corrected DOC concentration range. The absence of change in the LCu EC50, despite increased HA concentration, suggests that the LCu fraction, not TCu, was responsible for the observed toxicity to the oyster embryo. This corresponds with the current understanding of copper toxicity and supports the free-ion activity model for copper toxicity.

Copper speciation in the gill microenvironment of carp (Cyprinus carpio) at various levels of pH.

PubMed

Tao, Shu; Long, Aimin; Xu, Fuliu; Dawson, R W

2002-07-01

The fish gill microenvironment of Cyprinus carpio under stress of copper exposure was investigated. pH and other parameters including free copper activity, alkalinity, and inorganic and organic carbons in the surrounding water (inspired water) and in the gill microenvironment (expired water) were measured or calculated at various levels of pH and varying total copper concentrations. The chemical equilibrium calculation (from MINEQA2) and complexation modeling (mucus-copper) were coupled to calculate both species distribution. The results indicate that the pH in the fish gill microenvironment was different from that in the surrounding water with a balance point around 6.9. The secretion of both CO(2) and mucus was affected in both linear and nonlinear ways when the fish were exposed to elevated concentrations of copper. The complexation capacity of the gill mucus was characterized by a conditional stability constant (logk(Cu-mucus)) of 5.37 along with a complexation equivalent concentration (L(Cu-mucus)) of 0.96 mmol Cu/mg C. For both the fish microenvironment and the surrounding water, the dominant copper species shifted from Cu(2+) to CuCO(3)(0) and to Cu(OH)(2)(0) when the pH of the surrounding water changed from 6.12 to 8.11. The change in copper speciation in the gill microenvironment is smaller than that in the surrounding water due to the pH buffering capacity of the fish gills.

Design, Fabrication and Evaluation of Prototype Wayside Brake Inspection Sensors

DOT National Transportation Integrated Search

1980-06-01

Prototype Wayside instrumentation has been designed, developed, and tested that proves the feasibility of measuring braking system effectiveness on moving rail cars. The instrumentation system includes a specially designed short section of instrument...

Improvement and evaluation of thermal, electrical, sealing and mechanical contacts, and their interface materials

NASA Astrophysics Data System (ADS)

Luo, Xiangcheng

Material contacts, including thermal, electrical, seating (fluid sealing and electromagnetic sealing) and mechanical (pressure) contacts, together with their interface materials, were, evaluated, and in some cases, improved beyond the state of the art. The evaluation involved the use of thermal, electrical and mechanical methods. For thermal contacts, this work evaluated and improved the heat transfer efficiency between two contacting components by developing various thermal interface pastes. Sodium silicate based thermal pastes (with boron nitride particles as the thermally conductive filler) as well as polyethylene glycol (PEG) based thermal pastes were developed and evaluated. The optimum volume fractions of BN in sodium silicate based pastes and PEG based pastes were 16% and 18% respectively. The contribution of Li+ ions to the thermal contact conductance in the PEG-based paste was confirmed. For electrical contacts, the relationship between the mechanical reliability and electrical reliability of solder/copper and silver-epoxy/copper joints was addressed. Mechanical pull-out testing was conducted on solder/copper and silver-epoxy/copper joints, while the contact electrical resistivity was measured. Cleansing of the copper surface was more effective for the reliability of silver-epoxy/copper joint than that of solder/copper joint. For sealing contacts, this work evaluated flexible graphite as an electromagnetic shielding gasket material. Flexible graphite was found to be at least comparable to conductive filled silicone (the state of the art) in terms of the shielding effectiveness. The conformability of flexible graphite with its mating metal surface under repeated compression was characterized by monitoring the contact electrical resistance, as the conformability is important to both electromagnetic scaling and fluid waling using flexible graphite. For mechanical contacts, this work focused on the correlation of the interface structure (such as elastic/plastic deformation, oxidation, strain hardening, passive layer damage, fracture, etc.) with the electrical contact resistance, which was measured in real time for contacts under dynamic compression, thus allowing both reversible and irreversible changes to be observed. The materials studied included metals (carbon steel, stainless steel, aluminum and copper), carbon fiber reinforced polymer-matrix composite (nylon-6), ceramic (mortar) and graphite, due to their relevance to fastening, concrete structures, electric brushes and electrical pressure contacts.

Tactical Aviation Mission System Simulation Situational Awareness Project

DTIC Science & Technology

2004-04-01

prototyping and exercising human-machine systems and for measuring the impact of new technologies in a dynamic simulation environment. Theoretical...31 2.4.1 The Impact of an ERSTA-Like System on the CH-146 Mission Commander...was proven to be an effective platform for prototyping and exercising systems and for measuring the impact of new technologies in a dynamic simulation

A Prototype of Reflection Pulse Oximeter Designed for Mobile Healthcare.

PubMed

Lu, Zhiyuan; Chen, Xiang; Dong, Zhongfei; Zhao, Zhangyan; Zhang, Xu

2016-09-01

This paper introduces a pulse oximeter prototype designed for mobile healthcare. In this prototype, a reflection pulse oximeter is embedded into the back cover of a smart handheld device to offer the convenient measurement of both heart rate (HR) and SpO2 (estimation of arterial oxygen saturation) for home or mobile applications. Novel and miniaturized circuit modules including a chopper network and a filtering amplifier were designed to overcome the influence of ambient light and interferences that are caused by embedding the sensor into a flat cover. A method based on adaptive trough detection for improved HR and SpO2 estimation is proposed with appropriate simplification for its implementation on mobile devices. A fast and effective photoplethysmogram validation scheme is also proposed. Clinical experiments have been carried out to calibrate and test our oximeter. Our prototype oximeter can achieve comparable performance to a clinical oximeter with no significant difference revealed by paired t -tests ( p = 0.182 for SpO2 measurement and p = 0.496 for HR measurement). The design of this pulse oximeter will facilitate fast and convenient measurement of SpO2 for mobile healthcare.

Synthesis of Quaternary Ammonium Salts Based on Diketopyrrolopyrroles Skeletons and Their Applications in Copper Electroplating.

PubMed

Chen, Biao; Xu, Jie; Wang, Limin; Song, Longfeng; Wu, Shengying

2017-03-01

A series of DPP derivatives bearing quaternary ammonium salt centers with different lengths of carbon chains have been designed and synthesized. Their inhibition actions on copper electroplating were first investigated. A total of four diketopyrrolopyrrole (DPP) derivatives showed different inhibition capabilities on copper electroplating. To investigate interactions between metal surface and additives, we used quantum chemical calculations. Static and dynamic surface tension of four DPP derivatives had been measured, and the results showed DPP-10C (1c) with a faster-decreasing rate of dynamic surface tension among the four derivatives, which indicated higher adsorption rate of additive on the cathode surface and gives rise to stronger inhibiting effect of copper electrodeposition. Then, DPP-10C (1c) as the representative additive, was selected for the systematic study of the leveling influence during microvia filling through comprehensive electroplating tests. In addition, field-emission scanning electron microscope images and X-ray diffraction results showed the surface morphology, which indicated that addition of DPP derivative (1c) could lead a fine copper deposit and cause the preferential orientations of copper deposits to change from [220] to [111], which happened in particular at higher concentrations.

Retention of atmospheric Cu, Ni, Cd and Zn in an ombrotrophic peat profile near the Outokumpu Cu-Ni mine, SE-Finland

NASA Astrophysics Data System (ADS)

Rausch, N.; Nieminen, T. M.; Ukonmaanaho, L.; Cheburkin, A.; Krachler, M.; Shotyk, W.

2003-05-01

Peat cores taken from ombrotrophic bogs are widely used to reconstruct historical records of atmospheric lead and mercury déposition[1, 2]. In this study, the retention of copper, nickel, cadmium and zinc in peat bogs are studied by comparing high resolution, age dated concentration profiles with emissions from the main local source, the Outokumpu copper-nickel mine. An ombrotrophic peat core was taken from the vicinity of Outokumpu, E Finland. Copper and zinc concentrations of dry peat were measured by XRF, cadmium and nickel by GF-AAS, and sample ages by 210Pb. Only copper and nickel show enhanced concentrations in layers covering the mining period, indicating a retention of these elements. However, the more detailed comparison of ore production rates and concentrations in age-dated samples show clearly that only copper is likely to be permanently fixed, while nickel doesn't reflect the mining activity. Even though copper is retained in the upper part of the profile, a possible redeposition of this element by secondary processes (e.g., water table fluctuations) can not be excluded. This question will be resolved by further investigations, e.g. by pore water profiles.

Measured Copper Toxicity to Cnesterodon decemmaculatus (Pisces: Poeciliidae) and Predicted by Biotic Ligand Model in Pilcomayo River Water: A Step for a Cross-Fish-Species Extrapolation

PubMed Central

Casares, María Victoria; de Cabo, Laura I.; Seoane, Rafael S.; Natale, Oscar E.; Castro Ríos, Milagros; Weigandt, Cristian; de Iorio, Alicia F.

2012-01-01

In order to determine copper toxicity (LC50) to a local species (Cnesterodon decemmaculatus) in the South American Pilcomayo River water and evaluate a cross-fish-species extrapolation of Biotic Ligand Model, a 96 h acute copper toxicity test was performed. The dissolved copper concentrations tested were 0.05, 0.19, 0.39, 0.61, 0.73, 1.01, and 1.42 mg Cu L−1. The 96 h Cu LC50 calculated was 0.655 mg L−1 (0.823 − 0.488). 96-h Cu LC50 predicted by BLM for Pimephales promelas was 0.722 mg L−1. Analysis of the inter-seasonal variation of the main water quality parameters indicates that a higher protective effect of calcium, magnesium, sodium, sulphate, and chloride is expected during the dry season. The very high load of total suspended solids in this river might be a key factor in determining copper distribution between solid and solution phases. A cross-fish-species extrapolation of copper BLM is valid within the water quality parameters and experimental conditions of this toxicity test. PMID:22523491

On-site infiltration of a copper roof runoff: role of clinoptilolite as an artificial barrier material.

PubMed

Athanasiadis, Konstantinos; Helmreich, Brigitte; Horn, Harald

2007-08-01

On-site infiltration may be considered as a promising way of managing rainwater runoffs in urban areas, provided the hydrological and ecological conditions allow infiltration, and provided there is adequate treatment of the contaminants to avoid a risk of soil and groundwater pollution. The aim of this study was to evaluate the feasibility of the application of a new technical infiltration system equipped with clinoptilolite as an artificial barrier material for the treatment of the copper roof runoff of the Academy of Fine Arts in Munich, Germany. During the 2-yr sampling period, 30 rain events were examined. The cover material of the roof and the drainage system was responsible for the high copper concentrations in the roof runoff. The rain height and the rain intensity were of great significance regarding the establishment of the copper runoff rate. The technical infiltration system applied was able to reduce the copper from the roof runoff by a factor up to 96%. The mean measured copper concentration in percolation water was lower than the critical value of 50 microg/l set by the German Federal Soil Protection Act and Ordinance, indicating no risk for soil and groundwater contamination.

Cleaning and passivation of copper surfaces to remove surface radioactivity and prevent oxide formation

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

Hoppe, Eric W.; Seifert, Allen; Aalseth, Craig E.

High-purity copper is an attractive material for constructing ultra-low-background radiation measurement devices. Many low-background experiments using high-purity copper have indicated surface contamination emerges as the dominant background. Radon daughters plate out on exposed surfaces, leaving a residual 210Pb background that is difficult to avoid. Dust is also a problem; even under cleanroom conditions, the amount of U and Th deposited on surfaces can represent the largest remaining background. To control these backgrounds, a copper cleaning chemistry has been developed. Designed to replace an effective, but overly aggressive concentrated nitric acid etch, this peroxide-based solution allows for a more controlled cleaningmore » of surfaces. The acidified hydrogen peroxide solution will generally target the Cu+/Cu2+ species which are the predominant surface participants, leaving the bulk of copper metal intact. This preserves the critical tolerances of parts and eliminates significant waste disposal issues. Accompanying passivation chemistry has also been developed that protects copper surfaces from oxidation. Using a high-activity polonium surface spike, the most difficult-to-remove daughter isotope of radon, the performance of these methods are quantified. © 2001 Elsevier Science. All rights reserved« less

Selenium, copper, zinc, iron levels and mortality in patients with sepsis and systemic inflammatory response syndrome in Western Black Sea Region, Turkey.

PubMed

Ayoglu, Hilal; Sezer, Ustun; Akin, Mehmet; Okyay, Dilek; Ayoglu, Ferruh; Can, Murat; Kucukosman, Gamze; Piskin, Ozcan; Aydin, Bengu; Cimencan, Murat; Gur, Abdullah; Turan, Isil

2016-04-01

To evaluate the changing levels of selenium, copper, zinc and iron in patients with sepsis and systemic inflammatory response syndrome and their influence on mortality. The prospective study was conducted at a tertiary care university hospital in Zonguldak city in the western Black Sea region of Turkey from January 2012 to December 2013, and comprised patients with sepsis and systemic inflammatory response syndrome. Blood samples were taken on 1st, 3rd, 5th and 7th days to measure serum selenium, copper, zinc and iron levels. Patients' demographic data, presence of additional diseases and mortality were recorded. Of the 57 patients, 28(49.1%) were female and 29(50.9%) were male, with an overall mean age of 60.3±19.4 years, mean height of 166.1±11.4cm, mean weight of 76.5±17.5kg. Copper and zinc levels were in the normal range, while selenium and iron levels were lower than the limit values at all measuring periods. There was no significant difference between first and other days in accordance with element levels (p>0.05). Baseline copper levels in patients with malignancy were lower than patients without malignancy (p< 0.05). In hypertensive patients, baseline copper levels were higher and 7th day levels were lower than non-hypertensive (p< 0.05). Baseline selenium levels of those who died were lower than the other patients (p< 0.05). Selenium and iron levels were decreased in patients with sepsis-systemic inflammatory response syndrome and copper levels were lower in patients with malignancy, hypertension and chronic obstructive pulmonary disease (p< 0.05). There was no change in zinc levels of the patients. Reduced basal selenium levels of patients with sepsis and systemic inflammatory response syndrome were associated with mortality.

SU-D-209-02: Percent Depth Dose Curves for Fluoroscopic X-Ray Beam Qualities Incorporating Copper Filtration

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

Wunderle, K; Wayne State University School of Medicine, Detroit, MI; Godley, A

Purpose: The purpose of this investigation was to quantify percent depth dose (PDD) curves for fluoroscopic x-ray beam qualities incorporating added copper filtration. Methods: A PTW (Freiburg, Germany) MP3 water tank was used with a Standard Imaging (Middleton, WI) Exradin Model 11 Spokas Chamber to measure PDD curves for 60, 80, 100 and 120 kVp x-ray beams with copper filtration ranging from 0.0–0.9 mm at 22cm and 42cm fields of view from 0 to 150 mm of water. A free-in-air monitor chamber was used to normalize the water tank data to fluctuations in output from the fluoroscope. The measurements weremore » acquired on a Siemens (Erlangen, Germany) Artis ZeeGo fluoroscope. The fluoroscope was inverted from the typical orientation providing an x-ray beam originating from above the water tank. The water tank was positioned so that the water level was located at 60cm from the focal spot; which also represents the focal spot to interventional reference plane distance for that fluoroscope. Results: PDDs for 60, 80, 100, and 120 kVp with 0 mm of copper filtration compared well to previously published data by Fetterly et al. [Med Phys, 28, 205 (2001)] for those beam qualities given differences in fluoroscopes, geometric orientation, type of ionization chamber, and the water tank used for data collection. PDDs for 60, 80, 100, and 120 kVp with copper filtration were obtained and are presented, which have not been previously investigated and published. Conclusion: The equipment and processes used to acquire the reported data were sound and compared well with previously published data for PDDs without copper filtration. PDD data for the fluoroscopic x-ray beams incorporating copper filtration can be used as reference data for estimating organ or soft tissue dose at depth involving similar beam qualities or for comparison with mathematical models.« less

Age differences in alcohol prototype perceptions and willingness to drink in U.K. adolescents.

PubMed

Davies, Emma L; Martin, Jilly; Foxcroft, David R

2016-01-01

Using the prototype willingness model (PWM) as a framework, this study sought to explore the relationship between prototype perceptions, willingness and alcohol consumption in a sample of adolescents in the United Kingdom (UK). Adolescents aged 11-17 were asked about their alcohol prototype perceptions, willingness to drink, intentions, alcohol consumption, drunkenness and harms using a cross-sectional online survey. Participants were recruited through opportunity sampling via schools and parents. The survey was completed by 178 respondents (51% female; 91 aged 11-15, 87 aged 16-17). Multivariate analysis revealed significant differences between participants aged 11-15 and 16-17 on PWM measures, even when experience with drinking was accounted for (p < .001). There were significant interactions (p < .001) between age and prototype perceptions; younger participants rated non-drinker prototypes as more favourable and more similar to the self than 16- and 17-year-old participants. Willingness and intentions interacted with age; both measures were similar in 16- and 17-year-olds, whereas younger participants scored significantly higher on willingness than intentions (p < .001). Three distinct scales of prototype descriptions were identified in principal components analysis. Characteristics related to sociability significantly predicted willingness to drink alcohol in the sample (p < .001). This study extends previous research by demonstrating that the PWM can provide a theoretical explanation of adolescent drinking in the UK. The results suggest that 11- to 15-year-olds may be the most suitable age for an intervention that targets alcohol prototypes, with a focus on sociability characteristics.

Gold-coated copper cone detector as a new standard detector for F2 laser radiation at 157 nm.

PubMed

Kück, Stefan; Brandt, Friedhelm; Taddeo, Mario

2005-04-20

A new standard detector for high-accuracy measurements of F2 laser radiation at 157 nm is presented. This gold-coated copper cone detector permits the measurement of average powers up to 2 W with an uncertainty of approximately 1%. To the best of our knowledge, this is the first highly accurate standard detector for F2 laser radiation for this power level. It is fully characterized according to Guide to the Expression of Uncertainty in Measurement of the International Organization for Standardization and is connected to the calibration chain for laser radiation established by the German National Metrology Institute.

Ductile film delamination from compliant substrates using hard overlayers

PubMed Central

Cordill, M.J.; Marx, V.M.; Kirchlechner, C.

2014-01-01

Flexible electronic devices call for copper and gold metal films to adhere well to polymer substrates. Measuring the interfacial adhesion of these material systems is often challenging, requiring the formulation of different techniques and models. Presented here is a strategy to induce well defined areas of delamination to measure the adhesion of copper films on polyimide substrates. The technique utilizes a stressed overlayer and tensile straining to cause buckle formation. The described method allows one to examine the effects of thin adhesion layers used to improve the adhesion of flexible systems. PMID:25641995

Ductile film delamination from compliant substrates using hard overlayers.

PubMed

Cordill, M J; Marx, V M; Kirchlechner, C

2014-11-28

Flexible electronic devices call for copper and gold metal films to adhere well to polymer substrates. Measuring the interfacial adhesion of these material systems is often challenging, requiring the formulation of different techniques and models. Presented here is a strategy to induce well defined areas of delamination to measure the adhesion of copper films on polyimide substrates. The technique utilizes a stressed overlayer and tensile straining to cause buckle formation. The described method allows one to examine the effects of thin adhesion layers used to improve the adhesion of flexible systems.

Effects of Different Containers on Radioactivity Measurements using a Dose Calibrator with Special Reference to 111In and 123I.

PubMed

Inoue, Yusuke; Abe, Yutaka; Kikuchi, Kei; Miyatake, Hiroki; Watanabe, Atsushi

2017-01-01

Low-energy characteristic x-rays emitted by 111 In and 123 I sources are easily absorbed by the containers of the sources, affecting radioactivity measurements using a dose calibrator. We examined the effects of different containers on the estimated activities. The radioactivities of 111 In, 123 I, 201 Tl, and 99m Tc were measured in containers frequently employed in clinical practice in Japan. The 111 In measurements were performed in the vials A and B of the 111 In-pentetreotide preparation kit and in the plastic syringe. The activities of 123 I-metaiodobenzylguanidine and 201 Tl chloride were measured in the prefilled glass syringes and plastic syringes. The milking vial, vial A, vial B, and plastic syringe were used to assay 99m Tc. For 111 In and 123 I, measurements were performed with and without a copper filter. The filter was inserted into the well of the dose calibrator to absorb low-energy x-rays. The relative estimate was defined as the ratio of the activity estimated with the dose calibrator to the standard activity. The estimated activities varied greatly depending on the container when 111 In and 123 I sources were assayed without the copper filter. The relative estimates of 111 In were 0.908, 1.072, and 1.373 in the vial A, vial B, and plastic syringe, respectively. The relative estimates of 123 I were 1.052 and 1.352 in the glass syringe and plastic syringe, respectively. Use of the copper filter eliminated the container-dependence in 111 In and 123 I measurements. Container-dependence was demonstrated in neither 201 Tl nor 99m Tc measurements. The activities of 111 In and 123 I estimated with a dose calibrator differ greatly among the containers. Accurate estimation may be attained using the container-specific correction factor or using the copper filter.

Clinical prototype of a plastic water-equivalent scintillating fiber dosimeter array for QA applications.

PubMed

Lacroix, Fréderic; Archambault, Louis; Gingras, Luc; Guillot, Mathieu; Beddar, A Sam; Beaulieu, Luc

2008-08-01

A clinical prototype of a scintillating fiber dosimeter array for quality assurance applications is presented. The array consists of a linear array of 29 plastic scintillation detectors embedded in a water-equivalent plastic sheet coupled to optical fibers used to guide optical photons to a charge coupled device (CCD) camera. The CCD is packaged in a light-tight, radiation-shielded housing designed for convenient transport. A custom designed connector is used to ensure reproducible mechanical positioning of the optical fibers relative to the CCD. Profile and depth dose characterization measurements are presented and show that the prototype provides excellent dose measurement reproducibility (+/-0.8%) in-field and good accuracy (+/-1.6% maximum deviation) relative to the dose measured with an IC10 ionization chamber.

Design and first plasma measurements of the ITER-ECE prototype radiometer

DOE PAGES

Austin, M. E.; Brookman, M. W.; Rowan, W. L.; ...

2016-08-09

On ITER, second harmonic optically thick electron cyclotron emission (ECE) in the range of 220-340 GHz will supply the electron temperature (T e). In order to investigate the requirements and capabilities prescribed for the ITER system, a prototype radiometer covering this frequency range has been developed by Virginia Diodes, Inc. The first plasma measurements with this instrument have been carried out on the DIII-D tokamak, with lab bench tests and measurements of third through fifth harmonic ECE from high T e plasmas. At DIII-D the instrument shares the transmission line of the Michelson interferometer and can simultaneously acquire data. Inmore » our comparison of the ECE radiation temperature from the absolutely calibrated Michelson and the prototype receiver we show that the ITER radiometer provides accurate measurements of the millimeter radiation across the instrument band.« less

Improved estimates of environmental copper release rates from antifouling products.

PubMed

Finnie, Alistair A

2006-01-01

The US Navy Dome method for measuring copper release rates from antifouling paint in-service on ships' hulls can be considered to be the most reliable indicator of environmental release rates. In this paper, the relationship between the apparent copper release rate and the environmental release rate is established for a number of antifouling coating types using data from a variety of available laboratory, field and calculation methods. Apart from a modified Dome method using panels, all laboratory, field and calculation methods significantly overestimate the environmental release rate of copper from antifouling coatings. The difference is greatest for self-polishing copolymer antifoulings (SPCs) and smallest for certain erodible/ablative antifoulings, where the ASTM/ISO standard and the CEPE calculation method are seen to typically overestimate environmental release rates by factors of about 10 and 4, respectively. Where ASTM/ISO or CEPE copper release rate data are used for environmental risk assessment or regulatory purposes, it is proposed that the release rate values should be divided by a correction factor to enable more reliable generic environmental risk assessments to be made. Using a conservative approach based on a realistic worst case and accounting for experimental uncertainty in the data that are currently available, proposed default correction factors for use with all paint types are 5.4 for the ASTM/ISO method and 2.9 for the CEPE calculation method. Further work is required to expand this data-set and refine the correction factors through correlation of laboratory measured and calculated copper release rates with the direct in situ environmental release rate for different antifouling paints under a range of environmental conditions.

Degradation reaction of Diazo reactive black 5 dye with copper (II) sulfate catalyst in thermolysis treatment.

PubMed

Lau, Yen-Yie; Wong, Yee-Shian; Ang, Tze-Zhang; Ong, Soon-An; Lutpi, Nabilah Aminah; Ho, Li-Ngee

2018-03-01

The theme of present research demonstrates performance of copper (II) sulfate (CuSO 4 ) as catalyst in thermolysis process to treat reactive black 5 (RB 5) dye. During thermolysis without presence of catalyst, heat was converted to thermal energy to break the enthalpy of chemical structure bonding and only 31.62% of color removal. With CuSO 4 support as auxiliary agent, the thermally cleaved molecular structure was further destabilized and reacted with CuSO 4 . Copper ions functioned to delocalize the coordination of π of the lone paired electron in azo bond, C=C bond of the sp 2 carbon to form C-C of the sp 3 amorphous carbon in benzene and naphthalene. Further, the radicals of unpaired electrons were stabilized and RB 5 was thermally decomposed to methyl group. Zeta potential measurement was carried out to analyze the mechanism of RB 5 degradation and measurement at 0 mV verified the critical chemical concentration (CCC) (0.7 g/L copper (II) sulfate), as the maximum 92.30% color removal. The presence of copper (II) sulfate catalyst has remarkably increase the RB 5 dye degradation as the degradation rate constant without catalyst, k 1 is 6.5224 whereas the degradation rate constant with catalyst, k 2 is 25.6810. This revealed the correlation of conversion of thermal energy from heat to break the chemical bond strength, subsequent fragmentation of RB 5 dye molecular mediated by copper (II) sulfate catalyst. The novel framework on thermolysis degradation of molecular structure of RB 5 with respect to the bond enthalpy and interfacial intermediates decomposition with catalyst reaction were determined.

The Full-Scale Prototype for the Fluorescence Detector Array of Single-Pixel Telescopes

NASA Astrophysics Data System (ADS)

Fujii, T.; Malacari, M.; Bellido, J. A.; Farmer, J.; Galimova, A.; Horvath, P.; Hrabovsky, M.; Mandat, D.; Matalon, A.; Matthews, J. N.; Merolle, M.; Ni, X.; Nozka, L.; Palatka, M.; Pech, M.; Privitera, P.; Schovanek, P.; Thomas, S. B.; Travnicek, P.

The Fluorescence detector Array of Single-pixel Telescopes (FAST) is a design concept for the next generation of ultrahigh-energy cosmic ray (UHECR) observatories, addressing the requirements for a large-area, low-cost detector suitable for measuring the properties of the highest energy cosmic rays. In the FAST design, a large field of view is covered by a few pixels at the focal plane of a mirror or Fresnel lens. Motivated by the successful detection of UHECRs using a prototype comprised of a single 200 mm photomultiplier-tube and a 1 m2 Fresnel lens system, we have developed a new "full-scale" prototype consisting of four 200 mm photomultiplier-tubes at the focus of a segmented mirror of 1.6 m in diameter. We report on the status of the full-scale prototype, including test measurements made during first light operation at the Telescope Array site in central Utah, U.S.A.

A Nano-Thin Film-Based Prototype QCM Sensor Array for Monitoring Human Breath and Respiratory Patterns

PubMed Central

Selyanchyn, Roman; Wakamatsu, Shunichi; Hayashi, Kenshi; Lee, Seung-Woo

2015-01-01

Quartz crystal microbalance (QCM) sensor array was developed for multi-purpose human respiration assessment. The sensor system was designed to provide feedback for human respiration. Thorough optimization of measurement conditions: air flow, temperature in the QCM chamber, frequency measurement rate, and electrode position regarding to the gas flow—was performed. As shown, acquisition of respiratory parameters (rate and respiratory pattern) could be achieved even with a single electrode used in the system. The prototype system contains eight available QCM channels that can be potentially used for selective responses to certain breath chemicals. At present, the prototype machine is ready for the assessment of respiratory functions in larger populations in order to gain statistical validation. To the best of our knowledge, the developed prototype is the only respiratory assessment system based on surface modified QCM sensors. PMID:26263994

Acute gastrointestinal effects of graded levels of copper in drinking water.

PubMed Central

Pizarro, F; Olivares, M; Uauy, R; Contreras, P; Rebelo, A; Gidi, V

1999-01-01

The objective of this study was to determine the acute gastrointestinal effects caused by the consumption of drinking water containing graded levels of added copper. Sixty healthy, adult women were randomly assigned to receive copper [Cu(II)] at four concentrations in their drinking water following a Latin-square design. Each group (n = 15) received tap water with no added copper, 1, 3, and 5 mg Cu/l of added copper sulfate for a 2-week study period, followed by 1 week of standard tap water. The subjects recorded their water consumption and gastrointestinal symptoms daily on a special form. The average daily consumption of water was 1.64 liters per subject, regardless of the amount of copper added. Final serum copper, ceruloplasmin, and liver enzymes were measured in all subjects and were not different from baseline concentrations. Twenty-one subjects (35%) recorded gastrointestinal disturbances sometime during the study, 9 had diarrhea, some with abdominal pain and vomiting, and 12 subjects presented abdominal pain, nausea, or vomiting. There was no association between copper levels in drinking water and diarrhea. However, nausea, abdominal pain, or vomiting were significantly related to copper concentrations in water. The recorded incidence rate of these symptoms was 5, 2, 17, and 15% while ingesting water with 0, 1, 3, and 5 mg Cu/l, respectively (overall [chi]2 = 11.3, p<0.01; Cu [less than/equal to]1 mg/l versus Cu [Greater than/equal to]3 mg/l, [chi]2, p<0.01). When subjects interrupted their consumption of drinking water with added copper, most symptoms disappeared. We conclude that under the conditions of the study, there was no association between aggregate copper in drinking water within the range of 0-5 mg/l and diarrhea, but a [Greater than/equal to]3 mg Cu/l level of ionized copper was associated with nausea, abdominal pain, or vomiting. Additional studies with sufficient numbers of subjects are needed to define thresholds for specific gastrointestinal symptoms with precision and to extrapolate these results to the population at large. Images Figure 1 Figure 2 PMID:9924006

A chemical reduction approach to the synthesis of copper nanoparticles

NASA Astrophysics Data System (ADS)

Khan, Ayesha; Rashid, Audil; Younas, Rafia; Chong, Ren

2016-11-01

Development of improved methods for the synthesis of copper nanoparticles is of high priority for the advancement of material science and technology. Herein, starch-protected zero-valent copper (Cu) nanoparticles have been successfully synthesized by a novel facile route. The method is based on the chemical reduction in aqueous copper salt using ascorbic acid as reducing agent at low temperature (80 °C). X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray spectroscopy measurements were taken to investigate the size, structure and composition of synthesized Cu nanocrystals, respectively. Average crystallite size of Cu nanocrystals calculated from the major diffraction peaks using the Scherrer formula is about 28.73 nm. It is expected that the outcomes of the study take us a step closer toward designing rational strategies for the synthesis of nascent Cu nanoparticles without inert gas protection.

Analysis of S-nitrosothiols via Copper Cysteine (2C) and Copper Cysteine - Carbon Monoxide (3C) Methods

PubMed Central

Rogers, Stephen C.; Gibbons, Lindsey B.; Griffin, Sherraine; Doctor, Allan

2012-01-01

This chapter summarizes the principles of RSNO measurement in the gas phase, utilizing ozone-based chemiluminescence and the copper cysteine (2C) ± carbon monoxide (3C) reagent. Although an indirect method for quantifying RSNOs, this assay represents one of the most robust methodologies available. It exploits the NO• detection sensitivity of ozone based chemiluminscence, which is within the range required to detect physiological concentrations of RSNO metabolites. Additionally, the specificity of the copper cysteine (2C and 3C) reagent for RSNOs negates the need for sample pretreatment, thereby minimizing the likelihood of sample contamination (false positive results), NO species inter-conversion, or the loss of certain highly labile RSNO species. Herein, we outline the principles of this methodology, summarizing key issues, potential pitfalls and corresponding solutions. PMID:23116707

Biosorption of copper by cyanobacterial bloom-derived biomass harvested from the eutrophic Lake Dianchi in China.

PubMed

Wang, Kan; Colica, Giovanni; De Philippis, Roberto; Liu, Yongding; Li, Dunhai

2010-10-01

Biomass of cyanobacterial bloom from Lake Dianchi was used as a biosorbent for copper removal from aqueous solution. The maximum capacity was found at conditions of pH 4, initial concentration of copper was 10 mg/l and initial dose of biomass was 1.0 g/l. HNO(3) demonstrated the highest desorption efficiency compared with HCl, EDTA, and citric acid. Physical adsorption was assumed not to be the dominant mechanism of biosorption as revealed by scanning electron microscopy and surface area measurement of the biomass. Infrared ray spectra analysis of the biomass suggested that ion-exchange is the principal mechanism for biosorption. Considering the advantages-low cost, easy to collect, and huge in quantity-the Microcystis bloom biomass could be used as a sorbent for copper and other heavy metals removal.

Effects of short immersion time and cooling rates of copperizing process to the evolution of microstructures and copper behavior in the dead mild steel

NASA Astrophysics Data System (ADS)

Jatimurti, Wikan; Sutarsis, Cunika, Aprida Ulya

2017-01-01

In a dead mild steel with maximum carbon content of 0.15%, carbon does not contribute much to its strength. By adding copper as an alloying element, a balance between strength and ductility could be obtained through grain refining, solid solution, or Cu precipitation. This research aimed to analyse the changes in microstructures and copper behaviour on AISI 1006, including the phases formed, composition, and Cu dispersion. The addition of cooper was done by immersing steel into molten copper or so we called, copperizing using the principles of diffusion. Specimens were cut with 6 × 3 × 0.3 cm measurement then preheated to 900°C and melting the copper at 1100°C. Subsequently, the immersion of the specimens into molten copper varied to 5 and 7 minutes, and also varying the cooling rate to annealing, normalizing, and quenching. A series of test being conduct were optical microscope test, scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), optical emission spectroscopy (OES), and X-ray diffraction (XRD). The results showed that the longer the immersion time and slower cooling rate, the more Cu diffused causing smaller grain size with the highest Cu diffused recorded was 0.277% in the copperized AISI 1006 steel with 7 minutes of immersion and was annealed. The grain size reduced to 23041.5404 µm2. The annealed specimens show ferrite phase, the normalized ones show polygonal ferrite phase, while the quenched ones show granular bainite phase. The phase formed is single phase Cu. In addition, the normalized and quenched specimens show that Cu dissolved in Fe crystal forming solid solution.