A study of beryllium and beryllium-lithium complexes in single crystal silicon

NASA Technical Reports Server (NTRS)

Crouch, R. K.; Robertson, J. B.; Gilmer, T. E., Jr.

1972-01-01

When beryllium is thermally diffused into silicon, it gives rise to acceptor levels 191 MeV and 145 meV above the valence band. Quenching and annealing studies indicate that the 145-MeV level is due to a more complex beryllium configuration than the 191-MeV level. When lithium is thermally diffused into a beryllium-doped silicon sample, it produces two acceptor levels at 106 MeV and 81 MeV. Quenching and annealing studies indicate that these levels are due to lithium forming a complex with the defects responsible for the 191-MeV and 145-MeV beryllium levels, respectively. Electrical measurements imply that the lithium impurity ions are physically close to the beryllium impurity atoms. The ground state of the 106-MeV beryllium level is split into two levels, presumably by internal strains. Tentative models are proposed.

Eutectic structures in friction spot welding joint of aluminum alloy to copper

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

Shen, Junjun, E-mail: junjun.shen@hzg.de; Suhuddin, Uceu F. H.; Cardillo, Maria E. B.

2014-05-12

A dissimilar joint of AA5083 Al alloy and copper was produced by friction spot welding. The Al-MgCuAl{sub 2} eutectic in both coupled and divorced manners were found in the weld. At a relatively high temperature, mass transport of Cu due to plastic deformation, material flow, and atomic diffusion, combined with the alloy system of AA5083 are responsible for the ternary eutectic melting.

Thin film strain transducer

NASA Technical Reports Server (NTRS)

Rand, J. L. (Inventor)

1984-01-01

A strain transducer system and process for making the same is disclosed. A beryllium copper ring having four strain gages is electrically connected in Wheatstone bridge fashion to the output instrumentation. Tabs are bonded to a balloon or like surface with strain on the surface causing bending of a ring which provides an electrical signal through the gages proportional to the surface strain. A photographic pattern of a one half ring segment as placed on a sheet of beryllium copper for chem-mill etch formation is illustrated.

Diffusion bonding

DOEpatents

Anderson, Robert C.

1976-06-22

1. A method for joining beryllium to beryllium by diffusion bonding, comprising the steps of coating at least one surface portion of at least two beryllium pieces with nickel, positioning a coated surface portion in a contiguous relationship with an other surface portion, subjecting the contiguously disposed surface portions to an environment having an atmosphere at a pressure lower than ambient pressure, applying a force upon the beryllium pieces for causing the contiguous surface portions to abut against each other, heating the contiguous surface portions to a maximum temperature less than the melting temperature of the beryllium, substantially uniformly decreasing the applied force while increasing the temperature after attaining a temperature substantially above room temperature, and maintaining a portion of the applied force at a temperature corresponding to about maximum temperature for a duration sufficient to effect the diffusion bond between the contiguous surface portions.

Method for welding beryllium

DOEpatents

Dixon, Raymond D.; Smith, Frank M.; O'Leary, Richard F.

1997-01-01

A method is provided for joining beryllium pieces which comprises: depositing aluminum alloy on at least one beryllium surface; contacting that beryllium surface with at least one other beryllium surface; and welding the aluminum alloy coated beryllium surfaces together. The aluminum alloy may be deposited on the beryllium using gas metal arc welding. The aluminum alloy coated beryllium surfaces may be subjected to elevated temperatures and pressures to reduce porosity before welding the pieces together. The aluminum alloy coated beryllium surfaces may be machined into a desired welding joint configuration before welding. The beryllium may be an alloy of beryllium or a beryllium compound. The aluminum alloy may comprise aluminum and silicon.

Method for welding beryllium

DOEpatents

Dixon, R.D.; Smith, F.M.; O`Leary, R.F.

1997-04-01

A method is provided for joining beryllium pieces which comprises: depositing aluminum alloy on at least one beryllium surface; contacting that beryllium surface with at least one other beryllium surface; and welding the aluminum alloy coated beryllium surfaces together. The aluminum alloy may be deposited on the beryllium using gas metal arc welding. The aluminum alloy coated beryllium surfaces may be subjected to elevated temperatures and pressures to reduce porosity before welding the pieces together. The aluminum alloy coated beryllium surfaces may be machined into a desired welding joint configuration before welding. The beryllium may be an alloy of beryllium or a beryllium compound. The aluminum alloy may comprise aluminum and silicon. 9 figs.

Graphite fiber/copper matrix composites for space power heat pipe fin applications

NASA Astrophysics Data System (ADS)

McDanels, David L.; Baker, Karl W.; Ellis, David L.

1991-01-01

High specific thermal conductivity (thermal conductivity divided by density) is a major design criterion for minimizing system mass for space power systems. For nuclear source power systems, graphite fiber reinforced copper matrix (Gr/Cu) composites offer good potential as a radiator fin material operating at service temperatures above 500 K. Specific thermal conductivity in the longitudinal direction is better than beryllium and almost twice that of copper. The high specific thermal conductivity of Gr/Cu offers the potential of reducing radiator mass by as much as 30 percent. Gr/Cu composites also offer the designer a range of available properties for various missions and applications. The properties of Gr/Cu are highly anisotropic. Longitudinal elastic modulus is comparable to beryllium and about three times that of copper. Thermal expansion in the longitudinal direction is near zero, while it exceeds that of copper in the transverse direction.

Imaging and spectroscopy of copper dopant migration of indirectly driven Beryllium capsule implosion on the National Ignition Facility

NASA Astrophysics Data System (ADS)

Kyrala, George; Zylstra, A.; Yi, S. A.; Klline, J. L.; Shah, R. C.; Lopez, F. E.; Batha, S. A.; Doppner, T.; Thorn, D. B.; MacLaren, S.; Masters, N.; Callahan, D.; Hurricane, O.; Rice, N.; Huang, H.; Krauland, C. M.; MacDonald, M.

2017-10-01

Using beryllium, as an ablator material for indirectly driven inertial fusion, requires the use of a Copper dopant to block preheat from the hohlraum M-band radiation. However, due to the microstructure and imperfections of the capsule, some of the copper may be injected into the core of the implosion, affecting the yield and performance. Alternatively, the copper dopant may blow into the ablated plasma affecting the hohlraum performance as well. We will present some of data on time integrated imaging of the copper dopant into the core of the capsule using either the 2-dimensional multiple monochromatic imaging of the implosion, as well as the 1D spectrally resolved imaging of the copper dopant emission. In either case we found that the copper did migrate to the hot core, while fewer copper ions ablated into the hohlraum. This work performed under the auspices of the U.S. DOE by LANL under contract DE-AC52-06NA25396, and by LLNL under Contract DE-AC52-07NA27344.

Radiation hydrodynamic effects in two beryllium plates with an idealized aluminum joint

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

Belkov, S.A.; Mkhitarian, L.S.; Vinokurov, O.A.

A beryllium capsule formed from two hemispherical shells with a thin bond is one possible ignition target for the National Ignition Facility [J. A. Paisner {ital et al.}, Laser Focus World {bold 30}, 75 (1994)] Nonuniformities in density, opacity, and interface position at the joint between these hemishells will initiate two-dimensional (2-D) perturbations of the shock wave and material behind the shock as the shock passes through the shell perpendicular to the joint width. Rarefaction of material flow behind the shock front can cause the interface between the shell and joint material to oscillate in position. The amplitude of thesemore » oscillations may be comparable to the joint width. The evolution of these perturbations is studied by numerically simulating shock passage through flat beryllium plates containing aluminum joints. Using the MIMOSA-ND code [D. Sofronov {ital et al.}, Vopr. At. Nauki Tekh., Ser: Mat. modelirovanie fizicheskih processov {bold 2}, 3 (1990)] two different cases are calculated{emdash}a wide (10 {mu}m) and a narrow (1 {mu}m) joint of aluminum between two 150 {mu}m long semiinfinite beryllium plates. Both cases showed good agreement with an analytic representation of the oscillation behavior. For the narrow joint, a special technique allows the calculation of mixing between the joint and surrounding material caused by the Kelvin{endash}Helmholtz instability. {copyright} {ital 1999 American Institute of Physics.}« less

Effects of processing conditions and ambient environment on the microstructure and fracture strength of copper/niobium/copper interlayer joints for alumina

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

Marks, Robert Alan

1999-12-01

Partial transient liquid phase (PTLP) bonding is a technique which can be used to join ceramics with metals and is used to form niobium-based joints for alumina. The principal advantage to PTLP bonding is that it enables refractory joints to be fabricated at temperatures below those typically required by solid state diffusion bonding. A thorough review of the important parameters (chemical compatibility, thermal expansion match, sufficient wettability of the liquid phase on the solid phases) in choosing a joining material for ceramics by the PTLP method is provided. As in conventional PTLP joining, the current study uses thin (=3 μm)more » copper layers sandwiched between the alumina (bulk) and niobium (127 μm). However, unlike the case of copper/nickel/copper obium is limited. Consequently, the copper is not entirely dissolved in the process, resulting in a two phase (copper-rich and niobium-rich phases) microstructure. Different processing conditions (temperature and applied load) result in different morphologies of the copper-rich and niobium-rich phases at the interface. These different microstructures exhibit distinct strength characteristics. Extended annealing of as-processed joints can influence the strengths differently depending on the ambient partial oxygen pressure at the annealing temperature. The focus of this work is to correlate processing conditions, microstructure, and resulting joint strength. Under optimum processing conditions (1400°C, 2.2 MPa), joints with strengths in excess of 200 MPa at 1200°C are fabricated.« less

Beryllium in the environment: a review.

PubMed

Taylor, Tammy P; Ding, Mei; Ehler, Deborah S; Foreman, Trudi M; Kaszuba, John P; Sauer, Nancy N

2003-02-01

Beryllium is an important industrial metal because of its unusual material properties: it is lighter than aluminum and six times stronger than steel. Often alloyed with other metals such as copper, beryllium is a key component of materials used in the aerospace and electronics industries. Beryllium has a small neutron cross-section, which makes it useful in the production of nuclear weapons and in sealed neutron sources. Unfortunately, beryllium is one of the most toxic elements in the periodic table. It is responsible for the often-fatal lung disease, Chronic Beryllium Disease (CBD) or berylliosis, and is listed as a Class A EPA carcinogen. Coal-fired power plants, industrial manufacturing and nuclear weapons production and disposal operations have released beryllium to the environment. This contamination has the potential to expose workers and the public to beryllium. Despite the increasing use of beryllium in industry, there is surprisingly little published information about beryllium fate and transport in the environment. This information is crucial for the development of strategies that limit worker and public exposure. This review summarizes the current understanding of beryllium health hazards, current regulatory mandates, environmental chemistry, geochemistry and environmental contamination.

78 FR 42584 - Bureau of International Security and Nonproliferation: Report to Congress Pursuant to Section...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-16

...-finished metals such as aluminum and steel, coal, and software for integrating industrial processes. We...; boron; cobalt; copper; copper infiltrated tungsten; copper- beryllium; graphite; hastelloy; inconel; magnesium; molybdenum; nickel; niobium; silver infiltrated tungsten; steels (including, but not limited to...

METHOD OF BRAZING BERYLLIUM

DOEpatents

Hanks, G.S.; Keil, R.W.

1963-05-21

A process is described for brazing beryllium metal parts by coating the beryllium with silver (65- 75 wt%)-aluminum alloy using a lithium fluoride (50 wt%)-lithium chloride flux, and heating the coated joint to a temperature of about 700 un. Concent 85% C for about 10 minutes. (AEC)

Concept for a beryllium divertor with in-situ plasma spray surface regeneration

NASA Astrophysics Data System (ADS)

Smith, M. F.; Watson, R. D.; McGrath, R. T.; Croessmann, C. D.; Whitley, J. B.; Causey, R. A.

1990-04-01

Two serious problems with the use of graphite tiles on the ITER divertor are the limited lifetime due to erosion and the difficulty of replacing broken tiles inside the machine. Beryllium is proposed as an alternative low-Z armor material because the plasma spray process can be used to make in-situ repairs of eroded or damaged surfaces. Recent advances in plasma spray technology have produced beryllium coatings of 98% density with a 95% deposition efficiency and strong adhesion to the substrate. With existing technology, the entire active region of the ITER divertor surface could be coated with 2 mm of beryllium in less than 15 h using four small plasma spray guns. Beryllium also has other potential advantages over graphite, e.g., efficient gettering of oxygen, ten times less tritium inventory, reduced problems of transient fueling from D/T exchange and release, no runaway erosion cascades from self-sputtering, better adhesion of redeposited material, as well as higher strength, ductility, and fracture toughness than graphite. A 2-D finite element stress analysis was performed on a 3 mm thick Be tile brazed to an OFHC soft-copper saddle block, which was brazed to a high-strength copper tube. Peak stresses remained 50% below the ultimate strength for both brazing and in-service thermal stresses.

Microstructure Evolution During Stainless Steel-Copper Vacuum Brazing with a Ag/Cu/Pd Filler Alloy: Effect of Nickel Plating

NASA Astrophysics Data System (ADS)

Choudhary, R. K.; Laik, A.; Mishra, P.

2017-03-01

Vacuum brazing of stainless steel and copper plates was done using a silver-based filler alloy. In one set of experiments, around 30-µm-thick nickel coatings were electrochemically applied on stainless steel plates before carrying out the brazing runs and its effect in making changes in the braze-zone microstructure was studied. For brazing temperature of 830 °C, scanning electron microscopy examination of the braze-zone revealed that relatively sound joints were obtained when brazing was done with nickel-coated stainless steel than with uncoated one. However, when brazing of nickel-coated stainless steel and copper plates was done at 860 °C, a wide crack appeared in the braze-zone adjacent to copper side. Energy-dispersive x-ray analysis and electron microprobe analysis confirmed that at higher temperature, the diffusion of Cu atoms from copper plate towards the braze-zone was faster than that of Ni atoms from nickel coating. Helium leak rate of the order 10-11 Pa m3/s was obtained for the crack-free joint, whereas this value was higher than 10-4 Pa m3/s for the joint having crack. The shear strength of the joint was found to decrease considerably due to the presence of crack.

Destructive and non-destructive evaluation of cu/cu diffusion bonding with interlayer aluminum

NASA Astrophysics Data System (ADS)

Santosh Kumar, A.; Mohan, T.; Kumar, S. Suresh; Ravisankar, B.

2018-03-01

The current study is established an inspection procedure for assessing quality of diffusion bonded joints using destructive and non-destructive method. Diffusion bonding of commercially pure copper with aluminium interlayer was carried out uniaxial load at 15MPa for different temperatures under holding time 60 min in vacuum atmosphere. The bond qualities were determined by destructive and non-destructive testing method (ultrasonic C- scan). The bond interface and bonded samples were analysed using optical and scanning electron microscopy (SEM). The element composition of the fractured and bonded area is determined using the Energy Dispersive Spectrometry (EDS). The bond quality obtained by both testing methods and its parameters are correlated. The optimized bonding parameter for best bonding characteristics for copper diffusion bonding with aluminum interlayer is reported.

Development of Sediment Quality Values for Puget Sound. Volume 1.

DTIC Science & Technology

1986-09-01

62 cadmium CHROMIUM,63 chromium COPPER ,64 copper IRON ,65 iron LEAD ,66 lead MANGANES ,67 manganese NICKEL ,68 nickel SELENIUM,69 selenium SILVER ,70...BERYLLIU beryllium 67. CADMIUM cadmium 68. CHROMIUM chromium 69. COPPER copper 70. IRON iron 71. LEAD lead 72. MANGANES manganese 73. NICKEL nickel 74...they can also be strongly influenced by iron and manganese oxide and hydrous oxide surfaces (these phases can scavenge metals under oxidizing

Thin film strain transducer. [suitable for in-flight measurement of scientific balloon strain

NASA Technical Reports Server (NTRS)

Rand, J. L. (Inventor)

1985-01-01

A strain transducer system and process for making same is disclosed wherein a beryllium-copper ring having four strain gages disposed thereon is electrically connected in Wheatstone bridge fashion to output instrumentation. Tabs are bonded to a balloon or like surface with strain on the surface causing bending of the ring and providing an electrical signal through the gages proportional to the surface strain. A figure is provided which illustrates a pattern of a one-half ring segment as placed on a sheet of beryllium-copper for chem-mill etch formation, prior to bending and welding of a pair of the segments to form a ring structure.

Risk of beryllium sensitization in a low-exposed former nuclear weapons cohort from the Cold War era.

PubMed

Mikulski, Marek A; Leonard, Stephanie A; Sanderson, Wayne T; Hartley, Patrick G; Sprince, Nancy L; Fuortes, Laurence J

2011-03-01

The nuclear weapons industry has long been known as a source of beryllium exposure. A total of 1,004 former workers from a nuclear weapons assembly site in the Midwest were screened for sensitization to beryllium (BeS). The screenings were part of the Department of Energy (DOE) Former Worker Program established in 1996. Twenty-three (2.3%) workers were found sensitized to beryllium and this prevalence was comparable to other DOE sites. Occasional, direct exposure to beryllium through machining and grinding of copper-beryllium (Cu-Be) 2% alloy tools was found to increase the risk of sensitization compared to background exposure (OR = 3.83; 95% CI: 1.04-14.03) with a statistically significant trend (P = 0.03) revealing that particular jobs are associated with sensitization. Exposure potential in this study was estimated based on job titles and not personal exposure information. These results confirm the need to screen workers using beryllium alloy tools in other industries and for consideration of altering work practices. Copyright © 2010 Wiley-Liss, Inc.

Mechanical property determination of high conductivity metals and alloys

NASA Technical Reports Server (NTRS)

Harrod, D. L.; Vandergrift, E.; France, L.

1973-01-01

Pertinent mechanical properties of three high conductivity metals and alloys; namely, vacuum hot pressed grade S-200E beryllium, OFHC copper and beryllium-copper alloy no. 10 were determined. These materials were selected based on their possible use in rocket thrust chamber and nozzle hardware. They were procured in a form and condition similar to that which might be ordered for actual hardware fabrication. The mechanical properties measured include (1) tension and compression stress strain curves at constant strain rate (2) tensile and compressive creep, (3) tensile and compressive stress-relaxation behavior and (4) elastic properties. Tests were conducted over the temperature range of from 75 F to 1600 F. The resulting data is presented in both graphical and tabular form.

Method and apparatus for the management of hazardous waste material

DOEpatents

Murray, Jr., Holt

1995-01-01

A container for storing hazardous waste material, particularly radioactive waste material, consists of a cylindrical body and lid of precipitation hardened C17510 beryllium-copper alloy, and a channel formed between the mated lid and body for receiving weld filler material of C17200 copper-beryllium alloy. The weld filler material has a precipitation hardening temperature lower than the aging kinetic temperature of the material of the body and lid, whereby the weld filler material is post weld heat treated for obtaining a weld having substantially the same physical, thermal, and electrical characteristics as the material of the body and lid. A mechanical seal assembly is located between an interior shoulder of the body and the bottom of the lid for providing a vacuum seal.

40 CFR 421.153 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2013 CFR

2013-07-01

... Copper 2,875.000 1,370.000 Cyanide (total) 449.200 179.700 Ammonia (as N) 299,400.000 131,600.000... Beryllium 180.4 81.4 Chromium (total) 81.4 33.0 Copper 281.6 134.2 Cyanide (total) 44.0 17.6 Ammonia (as N... 79.370 Chromium (total) 79.370 32.180 Copper 274.600 130.800 Cyanide (total) 42.900 17.160 Ammonia...

40 CFR 421.153 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2010 CFR

2010-07-01

... Copper 2,875.000 1,370.000 Cyanide (total) 449.200 179.700 Ammonia (as N) 299,400.000 131,600.000... Beryllium 180.4 81.4 Chromium (total) 81.4 33.0 Copper 281.6 134.2 Cyanide (total) 44.0 17.6 Ammonia (as N... 79.370 Chromium (total) 79.370 32.180 Copper 274.600 130.800 Cyanide (total) 42.900 17.160 Ammonia...

40 CFR 421.153 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2014 CFR

2014-07-01

... Copper 2,875.000 1,370.000 Cyanide (total) 449.200 179.700 Ammonia (as N) 299,400.000 131,600.000... Beryllium 180.4 81.4 Chromium (total) 81.4 33.0 Copper 281.6 134.2 Cyanide (total) 44.0 17.6 Ammonia (as N... 79.370 Chromium (total) 79.370 32.180 Copper 274.600 130.800 Cyanide (total) 42.900 17.160 Ammonia...

40 CFR 421.153 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2012 CFR

2012-07-01

... Copper 2,875.000 1,370.000 Cyanide (total) 449.200 179.700 Ammonia (as N) 299,400.000 131,600.000... Beryllium 180.4 81.4 Chromium (total) 81.4 33.0 Copper 281.6 134.2 Cyanide (total) 44.0 17.6 Ammonia (as N... 79.370 Chromium (total) 79.370 32.180 Copper 274.600 130.800 Cyanide (total) 42.900 17.160 Ammonia...

40 CFR 421.153 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

Code of Federal Regulations, 2011 CFR

2011-07-01

... Copper 2,875.000 1,370.000 Cyanide (total) 449.200 179.700 Ammonia (as N) 299,400.000 131,600.000... Beryllium 180.4 81.4 Chromium (total) 81.4 33.0 Copper 281.6 134.2 Cyanide (total) 44.0 17.6 Ammonia (as N... 79.370 Chromium (total) 79.370 32.180 Copper 274.600 130.800 Cyanide (total) 42.900 17.160 Ammonia...

Influence of brazing conditions on the strength of brazed joints of alumina dispersion-strengthened copper to 316 stainless steel

NASA Astrophysics Data System (ADS)

Nishi, H.; Kikuchi, K.

1998-10-01

Brazing of alumina dispersion-strengthened copper (DS Cu) to 316 stainless steel were conducted in order to investigate the influence of filler metals and brazing conditions on the joint strength. The brazing were performed with a silver-base (BAg-8) and three kinds of gold-base (BAu-2,4,11) filler metals with varying brazing joint clearance and brazing time. The filler metal had a greater effect on the joint strength than the brazing joint clearance and brazing time. The joint with BAu-2 was superior to the joint with other filler metals. The tensile strength of the joint with BAu-2 was as large as that of DS Cu, however, the Charpy and low cycle fatigue strength were lower than those of DS Cu. The DS Cu melted near the brazed zone, consequently recrystallization and agglomeration of alumina occurred in the diffusion layer for all filler metals. The grain size after the recrystallization was small in order of BAu-2, BAu-4 and BAu-11, that was in accordance with the order of the brazing temperature. The excellent fracture strength for the joint with BAu-2 was attributed to the smallest grain size.

Friction and wear of selected metals and alloys in sliding contact with AISI 440 C stainless steel in liquid methane and in liquid natural gas

NASA Technical Reports Server (NTRS)

Wisander, D. W.

1978-01-01

Aluminum, titanium, beryllium, nickel, iron, copper, and several copper alloys were run in sliding contact with AISI 440C in liquid methane and natural gas. All of the metals run except copper and the copper alloys of tin and tin-lead showed severely galled wear scars. Friction coefficients varied from 0.2 to 1.0, the lowest being for copper, copper-17 wt. % tin, and copper-8 wt. % tin-22 wt. % lead. The wear rate for copper was two orders of magnitude lower than that of the other metals run. An additional order of magnitude of wear reduction was achieved by the addition of tin and/or lead to copper.

Method and apparatus for the management of hazardous waste material

DOEpatents

Murray, H. Jr.

1995-02-21

A container for storing hazardous waste material, particularly radioactive waste material, consists of a cylindrical body and lid of precipitation hardened C17510 beryllium-copper alloy, and a channel formed between the mated lid and body for receiving weld filler material of C17200 copper-beryllium alloy. The weld filler material has a precipitation hardening temperature lower than the aging kinetic temperature of the material of the body and lid, whereby the weld filler material is post weld heat treated for obtaining a weld having substantially the same physical, thermal, and electrical characteristics as the material of the body and lid. A mechanical seal assembly is located between an interior shoulder of the body and the bottom of the lid for providing a vacuum seal. 40 figs.

Interfacial microstructure and properties of copper clad steel produced using friction stir welding versus gas metal arc welding

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

Shen, Z.; Chen, Y.; Haghshenas, M., E-mail: mhaghshe@uwaterloo.ca

A preliminary study compares the feasibility and microstructures of pure copper claddings produced on a pressure vessel A516 Gr. 70 steel plate, using friction stir welding versus gas metal arc welding. A combination of optical and scanning electron microscopy is used to characterize the grain structures in both the copper cladding and heat affected zone in the steel near the fusion line. The friction stir welding technique produces copper cladding with a grain size of around 25 μm, and no evidence of liquid copper penetration into the steel. The gas metal arc welding of copper cladding exhibits grain sizes overmore » 1 mm, and with surface microcracks as well as penetration of liquid copper up to 50 μm into the steel substrate. Transmission electron microscopy reveals that metallurgical bonding is produced in both processes. Increased diffusion of Mn and Si into the copper cladding occurs when using gas metal arc welding, although some nano-pores were detected in the FSW joint interface. - Highlights: • Cladding of steel with pure copper is possible using either FSW or GMAW. • The FSW yielded a finer grain structure in the copper, with no evidence of cracking. • The FSW joint contains some evidence of nano-pores at the interface of the steel/copper. • Copper cladding by GMAW contained surface cracks attributed to high thermal stresses. • The steel adjacent to the fusion line maintained a hardness value below 248 HV.« less

The chloride induced localised corrosion of aluminium and beryllium: A study by electron and X-ray spectroscopies

NASA Astrophysics Data System (ADS)

Mallinson, Christopher F.

Beryllium is an important metal in the nuclear industry for which there are no suitable replacements. It undergoes localised corrosion at the site of heterogeneities in the metal surface. Corrosion pits are associated with a range of second phase particles. To investigate the role of these particles in corrosion, a safe experimental protocol was established using an aluminium alloy as a corrosion material analogue. The 7075-T6 alloy had not previously been investigated using the experimental methodology used in this thesis. This work led to the development of the experimental methodology and safe working practices for handling beryllium. The range and composition of the second phase particles present in S-65 beryllium billet were identified using a combination of SEM, AES, EDX and WDX. Following the identification of a range of particles with various compositions, including the AlFeBe4 precipitate which has been previously associated with corrosion, the location of the particles were marked to enable their repeated study. Attention was focused on the microchemistry in the vicinity of second phase particles, as a function of immersion time in pH 7, 0.1 M NaCl solution. The corrosion process associated with different particles was followed by repeatedly relocating the particles to perform analysis by means of SEM, AES and EDX. The use of traditional chlorinated vapour degreasing solvents on beryllium was investigated and compared to two modern commercially available cleaning solutions designed as drop-in replacements. This work expanded the range of solvents suitable for cleaning beryllium and validated the conclusions from previous thermodynamic modelling. Additionally, a new experimental methodology has been developed which enables the acquisition of chemical state information from the surface of micron scale features. This was applied to sub-micron copper and iron particles, as well as a copper intermetallic.

Extremely low-outgassing material: 0.2% beryllium copper alloy

NASA Astrophysics Data System (ADS)

Watanabe, Fumio

2004-01-01

Exploration for low-outgassing materials for use in ultrahigh vacuum and extreme high-vacuum systems is one of the most important topics of a vacuum researcher. We have found that a copper alloy containing 0.2% beryllium (0.2% BeCu) can attain an extremely low hydrogen outgassing rate of 10-14 Pa (H2) m/s order. Almost the entire surface of 0.2% BeCu is dominated by a BeO layer, after a 400 °C×72 h prebakeout treatment in an ultrahigh vacuum. This layer functions as a barrier to the processes of oxidization and permeation of hydrogen. In addition, this layer resists carbon contamination. Temperature-programmed desorption spectra show only a single peak for water at 150 °C and small quantities of any other desorption gases. Therefore, an in situ bakeout process in which the temperature simply ramps up to 150 °C and immediately ramps back down is enough for degassing; it does not require an ordinary sustained-temperature bakeout. Using an outgassing sample consisting of 0.2% BeCu disks housed in a 0.2% BeCu nipple chamber, a lowest outgassing rate of the 5.6×10-14 Pa (H2) m/s was measured by the pressure-rise method after pump cutoff. The pressure-rise versus time curve was completely nonlinear. It rises over time to a constant slope of 1/2 in a log-log plot, due to hydrogen diffusion from the bulk, but this requires over a week at room temperature. The hydrogen outgassing from the 0.2% BeCu bulk is completely dominated by a diffusion-limited mechanism. This article will describe why we obtain such low-outgassing rates with 0.2% BeCu. It is based on the observed surface changes with prebakeout treatment seen by x-ray photoelectron spectroscopy, and the improvement of hydrogen outgassing measurements by the pressure-rise method. A comparison is made to ordinary stainless steel. In addition, the concept of an outgassing reduction method will be discussed from a review of the published ultralow-outgassing data and reduction methods. .

The status of beryllium technology for fusion

NASA Astrophysics Data System (ADS)

Scaffidi-Argentina, F.; Longhurst, G. R.; Shestakov, V.; Kawamura, H.

2000-12-01

Beryllium was used for a number of years in the Joint European Torus (JET), and it is planned to be used extensively on the lower heat-flux surfaces of the reduced technical objective/reduced cost international thermonuclear experimental reactor (RTO/RC ITER). It has been included in various forms in a number of tritium breeding blanket designs. There are technical advantages but also a number of safety issues associated with the use of beryllium. Research in a variety of technical areas in recent years has revealed interesting issues concerning the use of beryllium in fusion. Progress in this research has been presented at a series of International Workshops on Beryllium Technology for Fusion. The most recent workshop was held in Karlsruhe, Germany on 15-17 September 1999. In this paper, a summary of findings presented there and their implications for the use of beryllium in the development of fusion reactors are presented.

40 CFR 302.6 - Notification requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... RQ of solid particles of antimony, arsenic, beryllium, cadmium, chromium, copper, lead, nickel.... 14, 1989; 63 FR 13475, Mar. 19, 1998; 63 FR 42189, Aug. 6, 1998; 64 FR 13114, Mar. 17, 1999; 65 FR...

40 CFR 302.6 - Notification requirements.

Code of Federal Regulations, 2014 CFR

2014-07-01

... RQ of solid particles of antimony, arsenic, beryllium, cadmium, chromium, copper, lead, nickel.... 14, 1989; 63 FR 13475, Mar. 19, 1998; 63 FR 42189, Aug. 6, 1998; 64 FR 13114, Mar. 17, 1999; 65 FR...

40 CFR 302.6 - Notification requirements.

Code of Federal Regulations, 2013 CFR

2013-07-01

... RQ of solid particles of antimony, arsenic, beryllium, cadmium, chromium, copper, lead, nickel.... 14, 1989; 63 FR 13475, Mar. 19, 1998; 63 FR 42189, Aug. 6, 1998; 64 FR 13114, Mar. 17, 1999; 65 FR...

Milan Army Ammunition Plant. Remedial Investigation Report. Volume 4. Appendices M - T

DTIC Science & Technology

1991-12-01

toxicity studies II. Hexavalent and trivalent chromium administered in drinking water to rats.. Arch. Ind. Health 18:232-234 Cobalt GILMAN, J.P.W...Beryllium Silver Cadmium Vanadium Calcium Chromium Copper Iron Lead Magnesium Manganese Nickel Potassium Sodium Zinc • . USATHAMA CERTIFIED AND UPPER...Arsenic AS 0.25 2.54 0.25 10 Barium BA 29.6 5 200 10,000 Beryllium BE 1.86 5 20 1,000 Cadmium CD 3.05 4 20 5,000 Calcium CA 59.0 500 5,000 20,000 Chromium

International Arctic Research Programs

DTIC Science & Technology

1989-07-01

beryllium graphite - (moonstone) cerium marble garnet chrniun ol ivine gronlandite copper phosphorus jasper gold soapstone kornerupine iron sulphur...Green- from the magnetic pole to the auroral zone. landic sea under marginal conditions where Besides these groundbased activities, mea- surements of

Remedial Investigation Report, Presidio Main Installation, Presidio of San Francisco. Volume 3: Figures Sections 1-5

DTIC Science & Technology

1997-01-01

0 REFCE02F01 -TDEPTH 0.0’ 0- 0 I° IE T.DEPTH 00 LITOLOGY MS UTHOLOGY MISC Beryllium ɘ.1 Beryllium Y0 A211I RF 5REFCF09 REFCF07 REFCFO4 REFCF01PT 7 T...LITHOLOGY FILL B`EID 1BE11D1Copper 18.300 7.290 f 29𔃼�a a DEPTH 0.2’ 2.2 5.9 * LITOLOGY BE/DU FILL BE/DU S!Copper 32.200 44.400T LF7SBO6 1 11-6 112...34IGATION RESULTS. LC7 Pa 2I 2 2.80 ,%as I.’. aa-2 RA .1" "co SKEET RANGE* 6s4 es2 DEPTH 4.3Ŗ’~iS • • ~ ~ LITOLOGY BEIDU OL At Lead ɟ.440 H A i DEPTH

The Structure and Properties of Diffusion Assisted Bonded Joints in 17-4 PH, Type 347, 15-5 PH and Nitronic 40 Stainless Steels

NASA Technical Reports Server (NTRS)

Wigley, D. A.

1981-01-01

Diffusion assisted bonds are formed in 17-4 PH, 15-5 PH, type 347 and Nitronic 40 stainless steels using electrodeposited copper as the bonding agent. The bonds are analyzed by conventional metallographic, electron microprobe analysis, and scanning electron microscopic techniques as well as Charpy V-notch impact tests at temperatures of 77 and 300 K. Results are discussed in terms of a postulated model for the bonding process.

Ion release from dental casting alloys as assessed by a continuous flow system: Nutritional and toxicological implications.

PubMed

López-Alías, José F; Martinez-Gomis, Jordi; Anglada, Josep M; Peraire, Maria

2006-09-01

The aims of this study were to quantify the metallic ions released by various dental alloys subjected to a continuous flow of saliva and to estimate the nutritional and toxicological implications of such a release. Four pieces of three nickel-based, one noble, one high-noble and two copper-aluminum alloys were cast and then immersed in a continuous flow of artificial saliva for 15 days. To simulate three meals a day, casts were subjected to thrice-daily episodes, lasting 30 min each and consisting of pH decreases and salinity increases. After 15 days, the metallic ions in the artificial saliva were analyzed. Data were expressed as averaged release rate: microg/cm2/day of ion released for each alloy. The highest value of 95% Cl of each ion was adapted to a hypothetical worst scenario of a subject with 100 cm2 of exposed metal surface. The results were compared with the tolerable upper daily intake level of each ion. The copper-aluminum alloys released copper, aluminum, nickel, manganese and iron. The nickel-based alloys essentially released nickel and chromium, while the beryllium-containing alloy released beryllium and significantly more nickel. The noble and high-noble alloys were very resistant to corrosion. The amount of ions released remained far below the upper tolerable intake level, with the exception of nickel, released by beryllium-containing nickel-based alloy, whose levels approach 50% of this threshold. The daily amount of ions released seems to be far below the tolerable upper intake levels for each ion.

Effect of flexure beam geometry and material on the displacement of piezo actuated diaphragm for micropump

NASA Astrophysics Data System (ADS)

Roopa, R.; Navin Karanth, P.; Kulkarni, S. M.

2018-02-01

In this paper, we present a COMSOL analysis of flexure diaphragm for piezo actuated valveless micropump. Diaphragms play an important role in micropumps, till now plane diaphragms are commonly used in micropumps. Use of compliant flexure hinges in diaphragm and other MEMS application is one of the new approach to achieving high deflection in diaphragm at low operating voltage. Flexures hinges in diaphragm acts as simply supported beam. Out-off plane compliance value and stiffness is considered for the selection of proper flexure for diaphragm. Diaphragm material also plays an important role in the diaphragm central deflection. Factor considered for diaphragm material selection is resilience; it is the ratio of yield stress to static modulus. Higher is the resilience will leads to higher deflection generated, it also imparts good compliance. Based on the resilience beryllium copper, stainless steel and brass materials are selected for diaphragm analysis. Simulations have been performed using COMSOL multiphysics. This study reports the effect of flexure hinge geometry and diaphragm material on the central deflection of diaphragms and compared with existing plane diaphragm. Simulation results illustrates that the deflection of three flexure diaphragm with 2mm width and 2mm length flexure is 6.75µm for stainless steel, 10.89 for beryllium copper and 12.10µm for brass, at 140V which is approximately twice that of plane diaphragm deflection. The maximum in both plane and three flexure diaphragm deflection is obtained for brass diaphragm compared to stainless steel and beryllium copper.

Beryllium

USGS Publications Warehouse

Foley, Nora K.; Jaskula, Brian W.; Piatak, Nadine M.; Schulte, Ruth F.; Schulz, Klaus J.; DeYoung,, John H.; Seal, Robert R.; Bradley, Dwight C.

2017-12-19

Beryllium is a mineral commodity that is used in a variety of industries to make products that are essential for the smooth functioning of a modern society. Two minerals, bertrandite (which is supplied domestically) and beryl (which is currently supplied solely by imports), are necessary to ensure a stable supply of high-purity beryllium metal, alloys, and metal-matrix composites and beryllium oxide ceramics. Although bertrandite is the source mineral for more than 90 percent of the beryllium produced globally, industrial beryl is critical for the production of the very high purity beryllium metal needed for some strategic applications. The current sole domestic source of beryllium is bertrandite ore from the Spor Mountain deposit in Utah; beryl is imported mainly from Brazil, China, Madagascar, Mozambique, and Portugal. High-purity beryllium metal is classified as a strategic and critical material by the Strategic Materials Protection Board of the U.S. Department of Defense because it is used in products that are vital to national security. Beryllium is maintained in the U.S. stockpile of strategic materials in the form of hot-pressed beryllium metal powder.Because of its unique chemical properties, beryllium is indispensable for many important industrial products used in the aerospace, computer, defense, medical, nuclear, and telecommunications industries. For example, high-performance alloys of beryllium are used in many specialized, high-technology electronics applications, as they are energy efficient and can be used to fabricate miniaturized components. Beryllium-copper alloys are used as contacts and connectors, switches, relays, and shielding for everything from cell phones to thermostats, and beryllium-nickel alloys excel in producing wear-resistant and shape-retaining high-temperature springs. Beryllium metal composites, which combine the fabrication ability of aluminum with the thermal conductivity and highly elastic modulus of beryllium, are ideal for producing aircraft and satellite structural components that have a high stiffness-to-weight ratio and low surface vibration. Beryllium oxide ceramics are used in a wide range of applications, including missile guidance systems, radar applications, and cell phone transmitters, and they are critical to medical technologies, such as magnetic resonance imaging (MRI) machines, medical lasers, and portable defibrillators.The United States is expected to remain self-sufficient with respect to most of its beryllium requirements, based on information available at the time this chapter was prepared (2013). The United States is one of only three countries that currently process beryllium ores and concentrate them into beryllium products, and these three countries supply most of the rest of the world with these products. Exploration for new deposits in the United States is limited because domestic beryllium production is dominated by a single producer that effectively controls the domestic beryllium market, which is relatively small and specialized, and the market cannot readily accommodate new competition on the raw material supply side.

Implanted Deuterium Retention and Release in Carbon-Coated Beryllium

NASA Astrophysics Data System (ADS)

Anderl, R. A.; Longhurst, G. R.; Pawelko, R. J.; Oates, M. A.

1997-06-01

Deuterium implantation experiments have been conducted on samples of clean and carbon-coated beryllium. These studies entailed preparation and characterization of beryllium samples coated with carbon thicknesses of 100, 500, and 1000 Å. Heat treatment of a beryllium sample coated with carbon to a thickness of approximately 100 Å revealed that exposure to a temperature of 400°C under high vacuum conditions was sufficient to cause substantial diffusion of beryllium through the carbon layer, resulting in more beryllium than carbon at the surface. Comparable concentrations of carbon and beryllium were observed in the bulk of the coating layer. Higher than expected oxygen levels were observed throughout the coating layer as well. Samples were exposed to deuterium implantation followed by thermal desorption without exposure to air. Differences were observed in deuterium retention and postimplantation release behavior in the carbon-coated samples as compared with bare samples. For comparable implantation conditions (sample temperature of 400°C and an incident deuterium flux of approximately 6 × 1019 D/m2-s), the quantity of deuterium retained in the bare sample was less than that retained in the carbon-coated samples. Further, the release of the deuterium took place at lower temperatures for the bare beryllium surfaces than for carbon-coated beryllium samples.

Compatibility of stainless steels and lithiated ceramics with beryllium

NASA Astrophysics Data System (ADS)

Flament, T.; Fauvet, P.; Sannier, J.

1988-07-01

The introduction of beryllium as a neutron multiplier in ceramic blankets of thermonuclear fusion reactors may give rise to the following compatibility problems: (i) oxidation of Be by ceramics (lithium aluminate and silicates) or by water vapour; (ii) interaction between beryllium and austenitic and martensitic steels. The studies were done in contact tests under vacuum and in tests under wet sweeping helium. The contact tests under vacuum have revealed that the interaction of beryllium with ceramics seems to be low up to 700°C, the interaction of beryllium with steels is significant and is characterized by the formation of a diffusion layer and of a brittle Be-Fe-Ni compound. With type 316 L austenitic steel, this interaction appears quite large at 600°C whereas it is noticeable only at 700°C with martensitic steels. The experiments carried out with sweeping wet helium at 600°C have evidenced a slight oxidation of beryllium due to water vapour which can be enhanced in the front of uncompletely dehydrated ceramics.

Purfication kinetics of beryllium during vacuum induction melting

NASA Technical Reports Server (NTRS)

Mukherjee, J. L.; Gupta, K. P.; Li, C. H.

1972-01-01

The kinetics of evaporation in binary alloys were quantitatively treated. The formalism so developed works well for several systems studied. The kinetics of purification of beryllium was studied through evaporation data actually acquired during vacuum induction melting. Normal evaporation equations are shown to be generally valid and useful for understanding the kinetics of beryllium purification. The normal evaporation analysis has been extended to cover cases of limited liquid diffusion. It was shown that under steady-state evaporation, the solute concentration near the surface may be up to six orders of magnitude different from the bulk concentration. Corrections for limited liquid diffusion are definitely needed for the highly evaporative solute elements, such as Zn, Mg, and Na, for which the computed evaporation times are improved by five orders of magnitude. The commonly observed logarithmic relation between evaporation time and final concentration further supports the validity of the normal evaporation equations.

Fracture toughness of copper-base alloys for ITER applications: A preliminary report

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

Alexander, D.J.; Zinkle, S.J.; Rowcliffe, A.F.

1997-04-01

Oxide-dispersion strengthened copper alloys and a precipitation-hardened copper-nickel-beryllium alloy showed a significant reduction in toughness at elevated temperature (250{degrees}C). This decrease in toughness was much larger than would be expected from the relatively modest changes in the tensile properties over the same temperature range. However, a copper-chromium-zirconium alloy strengthened by precipitation showed only a small decrease in toughness at the higher temperatures. The embrittled alloys showed a transition in fracture mode, from transgranular microvoid coalescence at room temperature to intergranular with localized ductility at high temperatures. The Cu-Cr-Zr alloy maintained the ductile microvoid coalescence failure mode at all test temperatures.

Release of beryllium from mineral ores in artificial lung and skin surface fluids.

PubMed

Duling, Matthew G; Stefaniak, Aleksandr B; Lawrence, Robert B; Chipera, Steve J; Virji, M Abbas

2012-06-01

Exposure to some manufactured beryllium compounds via skin contact or inhalation can cause sensitization. A portion of sensitized persons who inhale beryllium may develop chronic beryllium disease (CBD). Little is understood about exposures to naturally occurring beryllium minerals. The purpose of this study was to assess the bioaccessibility of beryllium from bertrandite ore. Dissolution of bertrandite from two mine pits (Monitor and Blue Chalk) was evaluated for both the dermal and inhalation exposure pathways by determining bioaccessibility in artificial sweat (pH 5.3 and pH 6.5), airway lining fluid (SUF, pH 7.3), and alveolar macrophage phagolysosomal fluid (PSF, pH 4.5). Significantly more beryllium was released from Monitor pit ore than Blue Chalk pit ore in artificial sweat buffered to pH 5.3 (0.88 ± 0.01% vs. 0.36 ± 0.00%) and pH 6.5 (0.09 ± 0.00% vs. 0.03 ± 0.01%). Rates of beryllium released from the ores in artificial sweat were faster than previously measured for manufactured forms of beryllium (e.g., beryllium oxide), known to induce sensitization in mice. In SUF, levels of beryllium were below the analytical limit of detection. In PSF, beryllium dissolution was biphasic (initial rapid diffusion followed by latter slower surface reactions). During the latter phase, dissolution half-times were 1,400 to 2,000 days, and rate constants were ~7 × 10(-10) g/(cm(2)·day), indicating that bertrandite is persistent in the lung. These data indicate that it is prudent to control skin and inhalation exposures to bertrandite dusts.

Sierra Army Depot, Phase 1, Remedial Investigation/Feasibility Study, Lassen County, California. Final Remedial Investigation

DTIC Science & Technology

1991-10-01

8.3.1.2 Cadmium ............................ 8-8 8.3.1.3 Lead .... ............................ 8-8 8.3.1.4 Zinc .... ............................ 8-8...Beryllium, Cadmium , Chromium, Cobalt, Copper, Fluoride Salts, Lead, Mercury, Molydenum, Nickel, Selenium, Silver, Thallium, Vanadium, Zinc . I ~ 2 ,4... cadmium (4.070 ;&g/L), copper (20.100 ug/L), and zinc (28.700 ug/L). Round 2 background 3 groundwater results include arsenic (7.700 g/L), barium

Over-Aging Effect on Fracture Toughness of Beryllium Copper Alloy C17200

NASA Astrophysics Data System (ADS)

Jen, Kei-Peng; Xu, Liqun; Hylinski, Steven; Gildersleeve, Nate

2008-10-01

This study experimentally increased the fracture toughness of Beryllium Copper (CuBe) UNS C17200 alloy using three different age hardening processes. At the same time, the micro- and macro-fracture behavior of this alloy were comprehensively studied. ASTM E399 fracture toughness, tensile, and Charpy impact tests were conducted for all three heat-treated rods. The fracture surfaces were examined under both an optical microscope and a scanning electron microscope to investigate the failure mechanisms. Multiple test orientations were considered to explore isotropy. Increasing the temperature and duration at which age hardening was performed increased fracture toughness while decreasing ultimate tensile strength. The maximum fracture toughness was reached on the most overaged specimen, while retaining a serviceable tensile strength. The specimen test data allowed a relationship to be established among Charpy impact toughness, fracture toughness, and yield strength. Analysis of fracture behavior revealed an interesting relationship between fracture toughness and pre-cracking fatigue propagation rate.

Laser-initiated combustion studies of selected aluminum, copper, iron, and nickel alloys

NASA Technical Reports Server (NTRS)

Bransford, J. W.; Clark, A. F.

1981-01-01

The results of combustion studies at atmospheric pressure on ten metal alloys are presented. The alloys studied were aluminum alloys 1100, 2219, 6061, and tensile-50; 304, 347 and 21-6-9 stainless steel; inconel 600; beryllium copper and a bronze. It was found that once ignition was achieved all alloys would generally burn to completion. The overall combustion process appears to obey a first order rate process. Preliminary conclusions are presented along with recommendations for future work.

High Accuracy Thermal Expansion Measurement At Cryogenic Temperatures

NASA Technical Reports Server (NTRS)

Stallcup, Michael; Presson, Joan; Tucker, James; Daspit, Gregory; Nein, Max

2003-01-01

A new, interferometer based system for measuring thermal expansion to an absolute accuracy of 20 ppb or better at cryogenic temperatures has been developed. Data from NIST Copper SRM 736 measured from room temperature to 15 K will be presented along with data from many other materials including beryllium, ULE, Zerodur, and composite materials. Particular attention will be given to a study by the Space Optics Manufacturing Technology Center (SOMTC) investigating the variability of ULE and beryllium materials used in the AMSD program. Approximately 20 samples of each material, tested from room temperature to below 30 K are compared as a function of billet location.

Map showing mineral resource potential of the Paiute Instant (Primitive) Study Area, Mohave County, Arizona

USGS Publications Warehouse

Villalobos, Hector A.; Hamm, Louis W.

1981-01-01

Several areas in the Paiute Instant Study Area are judged to have at best a low mineral potential. These include areas of copper, lead, manganese, molybdenum, nickel, silver, tungsten, and zinc mineralization, as well as occurrences of dumortierite, beryllium, arsenic, barium, gypsum, gem minerals, sand, gravel, and limestone. The metallic deposits and dumortieri te, beryllium, and arsenic occur over small surface areas. Significant production has not resulted from mining activity in mineralized areas. Sand, gravel, limestone, gem minerals, gypsum, and barium occurrences are far from major markets. Currently, there are no active mining operations in the study area.

High Accuracy Thermal Expansion Measurement at Cryogenic Temperatures

NASA Technical Reports Server (NTRS)

Tucker, Jim; Despit, Gregory; Stallcup, Michael; Presson, Joan; Nein, Max

2003-01-01

A new, interferometer-based system for measuring thermal expansion to an absolute accuracy of 20 ppb or better at cryogenic temperatures has been developed. Data from NIST Copper SRM 736 measured from room temperature to 15 K will be presented along with data from many other materials including beryllium, ULE, Zerodur, and composite materials. Particular attention will be given to a study by the Space Optics Manufacturing Technology Center (SOMTC) investigating the variability of ULE and beryllium materials used in the AMSD program Approximately 20 samples of each material, tested from room temperature to below 30 K are compared as a function of billet location.

Transition joints between Zircaloy-2 and stainless steel by diffusion bonding

NASA Astrophysics Data System (ADS)

Bhanumurthy, K.; Krishnan, J.; Kale, G. B.; Banerjee, S.

1994-11-01

The diffusion bonding between Zircaloy-2 and stainless steel (AISI 304L) using niobium, nickel and copper as intermediate layers has been investigated in the temperature range of 750 to 900°C. Bonding was carried out in a vacuum hot press, under compressive loading. Electron probe microanalysis and metallographic analysis showed a good metallurgical compatibility and also indicated the absence of discontunities, micropores and intermetallic compounds at various interfaces. The bond strength of the diffusion bonded assembly was found to be about 400 MPa for the couples bonded at 870°C for 2 h. The dimple structure on the fractured surface is indicative of the ductile mode of failure of the bonded assembly.

Manufacture, assembly, and delivery of beryllium test panels

NASA Technical Reports Server (NTRS)

1972-01-01

Details of the fabrication and assembly of two 99 cm by 99 cm (39 in. by 39 in.) beryllium heat shield test panels are presented. Each panel consists of two hat-stiffened, formed skins which overlap a transverse slip joint at the center of the panel; clips join the two skins at the slip joint, and continuous standoffs are provided at the ends of the panel. The hat-stiffeners are joined to the skin by furnace-brazing, using the braze alloy BAg 18. The parts are generally 0.051 cm (0.020 in.) thick. Tools used to form the detail parts are shown, together with the results of preliminary forming and brazing trials to verify processing techniques. Problems encountered in the manufacture of the panels are discussed.

Characterization and modeling of microstructural evolution of near-eutectic tin-silver-copper solder joints

NASA Astrophysics Data System (ADS)

Zbrzezny, Adam R.

Near-eutectic Sn-Ag-Cu (SAC) solders are currently considered as major lead-free replacement candidates for Sn-Pb eutectic alloys in microelectronics applications. In this thesis, the microstructural thermal stability including recrystallization, grain growth behavior, Pb and Au contamination effects and interaction of the SAC solder with Cu and Ni substrates were investigated. The true eutectic composition of the Sn-Ag-Cu alloy was verified to be Sn3.5Ag0.9Cu wt.%, and the eutectic melting temperature was determined to be 217.4 +/- 0.8°C. The system was classified as belonging to faceting (Cu6Sn5)-faceting (Ag3Sn)-nonfaceting (Sn matrix) ternary eutectic. The most significant consequence of Pb contamination was the formation of a quaternary eutectic phase (Sn-Ag-Cu-Pb) with a melting point at 176°C. Similarly, the presence of gold in the SAC alloy led to a development of a new quaternary phase (Sn-Ag-Cu-Au) melting at 204°C. Prolonged aging of SAC-4 wt.% Au on nickel resulted in the deposition of a new, previously unreported, intermetallic (IMC) layer, ((Au1-xCUx)6Sn 5, 15 wt.% of Au) on top of the existing (Cu1-yNi y)6Sn5 layer. The interfacial products that formed during soldering to copper were Cu6Sn5 and Cu3Sn. Soldering to nickel resulted in the formation of one layer, (Cu1-yNiy) 6Sn5, which was different from the expected Ni3Sn 4 layer. A small copper content in the SAC solder (0.7 wt.%) was sufficient to promote this thermodynamic shift. Intermetallic growth on Cu during solid state aging was established to be bulk diffusion controlled. The IMC layers in the SAC system grew at a slower rate than in the Sn-Pb system. It was found that the reliability of SAC solder joints on copper was considerably better than on nickel due to copper enrichment during reflow and subsequent Cu6Sn5 intermetallic precipitation. Enhanced copper and silver diffusion followed by tin recrystallization and grain growth, cavity nucleation and subsequent micro-crack linkage formed the framework of a proposed microstructural model of solder degradation mechanisms under cyclic creep conditions. A multilayer diffusion model of the SAC/Cu couple was proposed and employed for predicting intermetallic layer growth kinetics. In general, the calculated IMC thicknesses for short and intermediate aging times were in reasonable agreement with the experimental data.

Influence of nanomodification additives on the properties of multilayer composite coating obtained in laser surfacing

NASA Astrophysics Data System (ADS)

Cherepanov, A. N.; Orishich, A. M.; Ovcharenko, V. E.; Malikov, A. G.; Drozdov, V. O.; Pshenichnikov, A. P.

2017-10-01

The paper presents the results of numerical and experimental studies of the process of obtaining a permanent joint of two plates of heterogeneous metals that cannot be welded in the usual way: alloy Grade 4 and steel AISI 321 using a laser beam and an intermediate composite insert. The composite insert was obtained by explosion welding of four thin plates of titanium (Grade 4), niobium, copper, and steel (AISI 321). The insert was placed between the welded plates of titanium and steel, and the steel plate was welded with the steel part of the insert, and the titanium plate was welded with the titanium part of the insert. The plates were welded using a CO2 laser. The connection of metals with the help of explosion is carried out without their melting, so the formation of the brittle intermetallics does not occur in most cases. This ensures the greatest strength of the joints as compared to the joints obtained by other welding methods. To analyze the distribution of thermal fields in the composite insert and welded plates, a numerical study was conducted of the laser welding of steel and titanium plates with the corresponding parts of the insert. The purpose of the study was to determine the rational parameters of welding (laser beam power, speed of its movement, size and position of the focal spot), at which there was no complete melting of the steel and titanium parts of the insert during through penetration of the welded plates. The experimental part of the work is devoted to analysis of formation of the internal boundaries and microstructure of the composite insert and the strength of the permanent joint. It is shown that as a result of the explosion welding, weld seams of different wavelike configuration are formed. The most pronounced wavelike boundary is observed in the steel-copper connection, since these materials have a face-centered cubic lattice and are easily subjected to plastic deformation. At the contact boundaries of the plates, transition diffusion zones with different widths (from 5 to 40 μm) and element concentrations are formed. The hardness in the boundary diffusion zones is higher than in the connected metals, which is due to the diffusion interaction of the materials adjacent to each other. It has been established that the tensile strength of the composite insert is comparable to the maximum strength of Grade 4 alloy (456-511 MPa), and the failure in most cases occurred over the least durable component of the composite material, which is the copper plate, whose strength was significantly increased by cold hardening during explosion welding and diffusion of elements of the contacting plates.

Publications - SR 46 | Alaska Division of Geological & Geophysical Surveys

Science.gov Websites

, R.C., Wood, J.E., and Clough, A.H. Publication Date: 1991 Publisher: Alaska Division of Geological , R.C., Wood, J.E., and Clough, A.H., 1991, Alaska's mineral industry 1991: Alaska Division of ; Beryllium; Bismuth; Ceramics; Chromium; Coal; Cobalt; Construction Materials; Copper; Cultural Resources

Five-Megajoule Homopolar Upgrade

DTIC Science & Technology

1981-06-01

near the bearing lands to monitor temperature rise during motoring. AISI 4140 steel sleeves were shrunk onto the beryllium copper shaft of the new...MJ HPG in this upgrade. Rotor and Shaft A 0.75-m diameter, 0.28-m thick AISI 4340 air- craft quality steel rotor is shrunk on to a 0. 14-m diameter

Standard methods for chemical analysis of steel, cast iron, open-hearth iron, and wrought iron

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

None

1973-01-01

Methods are described for determining manganese, phosphorus, sulfur, selenium, copper, nickel, chromium, vanadium, tungsten, titanium, lead, boron, molybdenum ( alpha -benzoin oxime method), zirconium (cupferron --phosphate method), niobium and tantalum (hydrolysis with perchloric and sulfurous acids (gravimetric, titrimetric, and photometric methods)), and beryllium (oxide method). (DHM)

BIOLOGICAL MONITORING OF TOXIC TRACE METALS. VOLUME 2. TOXIC TRACE METALS IN PLANTS AND ANIMALS OF THE WORLD. PART II

EPA Science Inventory

The needs and priorities in using biological accumulator organisms for monitoring toxic trace metals in plants and animals are analyzed. The toxic trace metals selected for study are antimony, arsenic, beryllium, boron, cadmium, chromium, cobalt, copper, lead, mercury, nickel, se...

BIOLOGICAL MONITORING OF TOXIC TRACE METALS. VOLUME 2. TOXIC TRACE METALS IN PLANTS AND ANIMALS OF THE WORLD. PART I

EPA Science Inventory

The needs and priorities in using biological accumulator organisms for monitoring toxic trace metals in plants and animals are analyzed. The toxic trace metals selected for study are antimony, arsenic, beryllium, boron, cadmium, chromium, cobalt, copper, lead, mercury, nickel, se...

Investigation of Wear and Friction Properties Under Sliding Conditions of Some Materials Suitable for Cages of Rolling-Contact Bearings

NASA Technical Reports Server (NTRS)

Johnson, Robert L; Swikert, Max A; Bisson, Edmond E

1952-01-01

An investigation of wear and friction properties of a number of materials sliding against SAE 52100 steel was conducted. These materials included brass, bronze, beryllium copper, monel, nichrome v, 24s-t aluminum, nodular iron, and gray cast iron. The metals investigated may be useful as possible cage (separator or retainer) materials for rolling-contact bearings of high-speed turbine engines. The ability of materials to form surface films that prevent welding is a most important factor in both dry friction and boundary lubrication. On the basis of wear and resistance to welding only, the cast irons were the most promising materials investigated; they showed the least wear and the least tendency to surface failure when run dry, and when boundary lubricated they showed the highest load capacity. On the basis of mechanical properties, nodular iron is superior to gray cast iron. Bronze had the lowest friction coefficient under dry sliding conditions. The results with brass, beryllium copper, and aluminum were poor and these materials do not appear, with regard to friction and wear, to be suitable for cages.

Diffusion barriers in modified air brazes

DOEpatents

Weil, Kenneth Scott; Hardy, John S; Kim, Jin Yong; Choi, Jung-Pyung

2013-04-23

A method for joining two ceramic parts, or a ceramic part and a metal part, and the joint formed thereby. The method provides two or more parts, a braze consisting of a mixture of copper oxide and silver, a diffusion barrier, and then heats the braze for a time and at a temperature sufficient to form the braze into a bond holding the two or more parts together. The diffusion barrier is an oxidizable metal that forms either a homogeneous component of the braze, a heterogeneous component of the braze, a separate layer bordering the braze, or combinations thereof. The oxidizable metal is selected from the group Al, Mg, Cr, Si, Ni, Co, Mn, Ti, Zr, Hf, Pt, Pd, Au, lanthanides, and combinations thereof.

Diffusion barriers in modified air brazes

DOEpatents

Weil, Kenneth Scott [Richland, WA; Hardy, John S [Richland, WA; Kim, Jin Yong [Richland, WA; Choi, Jung-Pyung [Richland, WA

2010-04-06

A method for joining two ceramic parts, or a ceramic part and a metal part, and the joint formed thereby. The method provides two or more parts, a braze consisting of a mixture of copper oxide and silver, a diffusion barrier, and then heats the braze for a time and at a temperature sufficient to form the braze into a bond holding the two or more parts together. The diffusion barrier is an oxidizable metal that forms either a homogeneous component of the braze, a heterogeneous component of the braze, a separate layer bordering the braze, or combinations thereof. The oxidizable metal is selected from the group Al, Mg, Cr, Si, Ni, Co, Mn, Ti, Zr, Hf, Pt, Pd, Au, lanthanides, and combinations thereof.

High-strength braze joints between copper and steel

NASA Technical Reports Server (NTRS)

Kuhn, R. F.

1967-01-01

High-strength braze joints between copper and steel are produced by plating the faying surface of the copper with a layer of gold. This reduces porosity in the braze area and strengthens the resultant joint.

Reliability design and assessment of a micro-probe using the results of a tensile test of a beryllium-copper alloy thin film

NASA Astrophysics Data System (ADS)

Park, Jun-Hyub; Shin, Myung-Soo

2011-09-01

This paper describes the results of tensile tests for a beryllium-copper (BeCu) alloy thin film and the application of the results to the design of a probe. The copper alloy films were fabricated by electroplating. To obtain the tensile characteristics of the film, the dog-bone type specimen was fabricated by the etching method. The tensile tests were performed with the specimen using a test machine developed by the authors. The BeCu alloy has an elastic modulus of 119 GPa and the 0.2% offset yield and ultimate tensile strengths of 1078 MPa and 1108 MPa, respectively. The design and manufacture of a smaller probe require higher pad density and smaller pad-pitch chips. It should be effective in high-frequency testing. For the design of a new micro-probe, we investigated several design parameters that may cause problems, such as the contact force and life, using the tensile properties and the design of experiment method in conjunction with finite element analysis. The optimal dimensions of the probe were found using the response surface method. The probe with optimal dimensions was manufactured by a precision press process. It was verified that the manufactured probe satisfied the life, the contact force and the over drive through the compression tests and the life tests of the probes.

Self-generated Local Heating Induced Nanojoining for Room Temperature Pressureless Flexible Electronic Packaging

PubMed Central

Peng, Peng; Hu, Anming; Gerlich, Adrian P.; Liu, Yangai; Zhou, Y. Norman

2015-01-01

Metallic bonding at an interface is determined by the application of heat and/or pressure. The means by which these are applied are the most critical for joining nanoscale structures. The present study considers the feasibility of room-temperature pressureless joining of copper wires using water-based silver nanowire paste. A novel mechanism of self-generated local heating within the silver nanowire paste and copper substrate system promotes the joining of silver-to-silver and silver-to-copper without any external energy input. The localized heat energy was delivered in-situ to the interfaces to promote atomic diffusion and metallic bond formation with the bulk component temperature stays near room-temperature. This local heating effect has been detected experimentally and confirmed by calculation. The joints formed at room-temperature without pressure achieve a tensile strength of 5.7 MPa and exhibit ultra-low resistivity in the range of 101.3 nOhm·m. The good conductivity of the joint is attributed to the removal of organic compounds in the paste and metallic bonding of silver-to-copper and silver-to-silver. The water-based silver nanowire paste filler material is successfully applied to various flexible substrates for room temperature bonding. The use of chemically generated local heating may become a potential method for energy in-situ delivery at micro/nanoscale. PMID:25788019

New Cu(TiBN x ) copper alloy films for industrial applications

NASA Astrophysics Data System (ADS)

Lin, Chon-Hsin

2016-06-01

In this study, I explore a new type of copper alloy, Cu(TiBN x ), films by cosputtering Cu and TiB within an Ar/N2 gas atmosphere on Si substrates. The films are then annealed for 1 h in a vacuum environment at temperatures up to 700 °C. The annealed films exhibit not only excellent thermal stability and low resistivity but also little leakage current and strong adhesion to the substrates while no Cu/Si interfacial interactions are apparent. Within a Sn/Cu(TiBN x )/Si structure at 200 °C, the new alloy exhibits a minute dissolution rate, which is lower than that of pure Cu by at least one order of magnitude. Furthermore, the new alloy’s consumption rate is comparable to that of Ni commonly used in solder joints. The new films appear suitable for some industrial applications, such as barrierless Si metallization and new wetting and diffusion barrier layers required in flip-chip solder joints.

Speciation of copper diffused in a bi-porous molecular sieve

NASA Astrophysics Data System (ADS)

Huang, C.-H.; Paul Wang, H.; Wei, Y.-L.; Chang, J.-E.

2010-07-01

To better understand diffusion of copper in the micro- and mesopores, speciation of copper in a bi-porous molecular sieve (BPMS) possessing inter-connecting 3-D micropores (0.50-0.55 nm) and 2-D mesopores (4.1 nm) has been studied by X-ray absorption near edge structure (XANES) spectroscopy. It is found that about 77% (16% of CuO nanoparticles and 61% of CuO clusters) and 23% (CuO ads) of copper can be diffused into the meso- and micropores, respectively, in the BPMS. At least two diffusion steps in the BPMS may be involved: (i) free diffusion of copper in the mesopores and (ii) diffusion-controlled copper migrating into the micropores of the BPMS. The XANES data also indicate that diffusion rate of copper in the BPMS (4.68×10 -5 g/s) is greater than that in the ZSM-5 (1.11×10 -6 g/s) or MCM-41 (1.17×10 -5 g/s).

Star tracking reticles

NASA Technical Reports Server (NTRS)

Smith, W. O.; Toft, A. R. (Inventor)

1973-01-01

A method for the production of reticles, particularly those for use in outer space, where the product is a quartz base coated with highly adherent layers of chromium, chromium-silver, and silver vacuum deposited through a mask, and then coated with an electrodeposit of copper from a copper sulfate solution followed by an electrodeposit of black chromium is described. The masks are produced by coating a beryllium-copper alloy substrate with a positive working photoresist, developing the photoresist, according to a pattern to leave a positive mask, plating uncoated areas with gold, removing the photoresist, coating the substrate with a negative working photoresist, developing the negative working photoresist to expose the base metal of the pattern, and chemically etching the unplated side of the pattern to produce the mask.

Tritium retention in S-65 beryllium after 100 eV plasma exposure

NASA Astrophysics Data System (ADS)

Causey, Rion A.; Longhurst, Glen R.; Harbin, Wally

1997-02-01

The tritium plasma experiment (TPE) has been used to measure the retention of tritium in S-65 beryllium under conditions similar to that expected for the international thermonuclear experimental reactor (ITER). Beryllium samples 2 mm thick and 50 mm in diameter were exposed to a plasma of tritium and deuterium. The particle flux striking the samples was varied from approximately 1 × 10 17 ( D + T)/ cm2s up to about 3 × 10 18 ( D + T)/ cm2s. The beryllium samples were negatively biased to elevate the energy of the impinging ions to 100 eV. The temperature of the samples was varied from 373 K to 973 K. Exposure times of 1 h were used. Subsequent to the plasma exposure, the samples were outgassed in a separate system where 99% He and 1% H 2 gas was swept over the samples during heating. The sweep gas along with the released tritium was sent through an ionization chamber, through a copper oxide catalyst bed, and into a series of glycol bubblers. The amount of released tritium was determined both by the ionization chamber and by liquid scintillation counting of the glycol. Tritium retention in the beryllium disks varied from a high of 2.4 × 10 17 ( D + T)/ cm2 at 373 K to a low of 1 × 10 16 ( D + T)/ cm2 at 573 K. For almost every case, the tritium retention in the beryllium was less than that calculated using the C = 0 boundary condition at the plasma facing surface. It is believed that this lower than expected retention is due to rapid release of tritium from the large specific surface area created in the implant zone due to the production of voids, bubbles, and blisters.

A study of the durability of beryllium rocket engines. [space shuttle reaction control system

NASA Technical Reports Server (NTRS)

Paster, R. D.; French, G. C.

1974-01-01

An experimental test program was performed to demonstrate the durability of a beryllium INTEREGEN rocket engine when operating under conditions simulating the space shuttle reaction control system. A vibration simulator was exposed to the equivalent of 100 missions of X, Y, and Z axes random vibration to demonstrate the integrity of the recently developed injector-to-chamber braze joint. An off-limits engine was hot fired under extreme conditions of mixture ratio, chamber pressure, and orifice plugging. A durability engine was exposed to six environmental cycles interspersed with hot-fire tests without intermediate cleaning, service, or maintenance. Results from this program indicate the ability of the beryllium INTEREGEN engine concept to meet the operational requirements of the space shuttle reaction control system.

Effects of Beryllium and Compaction Pressure on the Thermal Diffusivity of Uranium Dioxide Fuel Pellets

NASA Astrophysics Data System (ADS)

Camarano, D. M.; Mansur, F. A.; Santos, A. M. M.; Ferraz, W. B.; Ferreira, R. A. N.

2017-09-01

In nuclear reactors, the performance of uranium dioxide (UO2) fuel is strongly dependent on the thermal conductivity, which directly affects the fuel pellet temperature, the fission gas release and the fuel rod mechanical behavior during reactor operation. The use of additives to improve UO2 fuel performance has been investigated, and beryllium oxide (BeO) appears as a suitable additive because of its high thermal conductivity and excellent chemical compatibility with UO2. In this paper, UO2-BeO pellets were manufactured by mechanical mixing, pressing and sintering processes varying the BeO contents and compaction pressures. Pellets with BeO contents of 2 wt%, 3 wt%, 5 wt% and 7 wt% BeO were pressed at 400 MPa, 500 MPa and 600 MPa. The laser flash method was applied to determine the thermal diffusivity, and the results showed that the thermal diffusivity tends to increase with BeO content. Comparing thermal diffusivity results of UO2 with UO2-BeO pellets, it was observed that there was an increase in thermal diffusivity of at least 18 % for the UO2-2 wt% BeO pellet pressed at 400 MPa. The maximum relative expanded uncertainty (coverage factor k = 2) of the thermal diffusivity measurements was estimated to be 9 %.

Erosion and Retention Properties of Beyllium

NASA Astrophysics Data System (ADS)

Doerner, R.; Grossman, A.; Luckhardt, S.; Serayderian, R.; Sze, F. C.; Whyte, D. G.

1997-11-01

Experiments in PISCES-B have investigated the erosion and hydrogen retention characteristics of beryllium. The sputtering yield is strongly influenced by trace amounts (≈1 percent) of intrinsic plasma impurities. At low sample exposure temperatures (below 250^oC), the beryllium surface remains free of contaminants and a sputtering yield similar to that of beryllium-oxide is measured. At higher exposure temperatures, impurities deposited on the surface can diffuse into the bulk and reduce their chance of subsequent erosion. These impurities form a surface layer mixed with beryllium which exhibits a reduced sputtering yield. Depth profile analysis has determined the composition and chemical bonding of the impurity layer. The hydrogen isotope retention of beryllium under ITER first wall (temperature = 200^oC, ion flux = 1 x 10^21 m-2 s-1) and baffle (temperature = 500^oC, ion flux = 1 x 10^22 m-2 s-1) conditions has been investigated. The retained deuterium saturates above a fluence of 10^23 m-2 at about 4 x 10^20 m-2 for the 200^oC exposure and at 2 x 10^20 m-2 for the 500^oC case. The TMAP code is used to model the deuterium release characteristics.

Structure formation and properties of a copper-aluminum joint produced by ultrasound-assisted explosive welding

NASA Astrophysics Data System (ADS)

Kuz'min, E. V.; Peev, A. P.; Kuz'min, S. V.; Lysak, V. I.

2017-08-01

The effect of ultrasound-assisted explosive welding on the structure formation and the properties of copper-aluminum joints is studied. Ultrasound-assisted explosive welding improves the quality of formed copper-aluminum joints, i.e., enhances their strength and significantly reduces the amount of fused metal over the entire weldability range. It is shown that ultrasound-assisted explosive welding can noticeably extend the weldability range of the copper-aluminum pair to obtain equal-in-strength joints with minimum structural heterogeneity in the wide welding range.

Mineral resources potential map of the Lost Cove and Harper Creek Roadless Areas, Avery and Caldwell counties, North Carolina

USGS Publications Warehouse

Crandall, T.M.; Ross, R.B.; Whitlow, J.W.; Griffitts, W.R.

1982-01-01

Mineral resources having low to moderate potential are gold and minerals of thorium, beryllium, niobium, and copper. Stone has a low economic potential; lead, molybdenum, and titanium have low resource potential. These conclusions are based on results of prospect examination, radiometric survey, geochemical survey of stream sediments, saprolite, and bedrock.

Failure Assessment Diagram for Titanium Brazed Joints

NASA Technical Reports Server (NTRS)

Flom, Yury; Jones, Justin S.; Powell, Mollie M.; Puckett, David F.

2011-01-01

The interaction equation was used to predict failure in Ti-4V-6Al joints brazed with Al 1100 filler metal. The joints used in this study were geometrically similar to the joints in the brazed beryllium metering structure considered for the ATLAS telescope. This study confirmed that the interaction equation R(sub sigma) + R(sub Tau) = 1, where R(sub sigma) and R(sub Tau)are normal and shear stress ratios, can be used as conservative lower bound estimate of the failure criterion in ATLAS brazed joints as well as for construction of the Failure Assessment Diagram (FAD).

Short- and long-term response to corticosteroid therapy in chronic beryllium disease.

PubMed

Marchand-Adam, S; El Khatib, A; Guillon, F; Brauner, M W; Lamberto, C; Lepage, V; Naccache, J-M; Valeyre, D

2008-09-01

Chronic beryllium disease (CBD) is a granulomatous disorder that affects the lung after exposure to beryllium. The present study reports short- and long-term evolution of granulomatous and fibrotic components in eight patients with severe CBD receiving corticosteroid therapy. Eight patients with confirmed CBD were studied at baseline, after initial corticosteroid treatment (4-12 months), at relapse and at the final visit. Beryllium exposure, Glu(69) (HLA-DPB1 genes coding for glutamate at position beta69) polymorphism, symptoms, pulmonary function tests (PFT), serum angiotensin-converting enzyme (SACE) and high-resolution computed tomography (HRCT) quantification of pulmonary lesions were analysed. The CBD patients were observed for a median (range) of 69 (20-180) months. After stopping beryllium exposure, corticosteroids improved symptoms and PFT (vital capacity +26%, diffusing capacity of the lung for carbon monoxide +15%), and decreased SACE level and active lesion HRCT score. In total, 18 clinical relapses occurred after the treatment was tapered and these were associated with SACE and active lesion HRCT score impairment. At the final visit, corticosteroids had completely stabilised all parameters including both HRCT scores of active lesions and fibrotic lesions in six out of eight patients. Corticosteroids were beneficial in chronic beryllium disease. They were effective in suppressing granulomatosis lesions in all cases and in stopping the evolution to pulmonary fibrosis in six out of eight patients.

The Explorer XVI Micrometeoroid Satellite Description and Preliminary Results for the Period December 16, 1962 Through January 13, 1963

NASA Technical Reports Server (NTRS)

Hastings, E. C., Jr.

1963-01-01

Explorer XVI (1962 Beta Chi l) data that have been analyzed for the period between December 16, 1962 (launch date), and January 13, 1963, indicate that the orbit achieved was close to the predicted orbit. Ten punctures of annealed 0.001-inch-thick beryllium-copper have been used to determine a puncture rate of 0.035 per square foot per day in this material. One puncture of a 0.002-inch-thick sample has also occurred in this period. A tentative evaluation of the puncture rate for the 0.001-inch beryllium-copper in terms of the rate for an equivalent thickness of aluminum has been attempted, and the result has been compared with two different puncture rate estimates. The three micrometeoroid impact detecting systems are operating. Counting rates for the high- and low-sensitivity systems were close to anticipated values near the end of one week. Two of the 0.001-inch-steel-covered grid detectors have been punctured, but none of the 0.003- or 0.006-inch-steel-covered grid detectors have indicated punctures. One of the cadmium sulfide cells indicates three punctures of the 0.00025-inch Mylar cover. None of the 0.002- or 0.003-inch-copper-wire cards have indicated a break in the period covered. Telemetry temperatures were initially higher than expected although they remained well within operating limits. Sensor temperatures have remained within the expected bounds.

Indirect Blood Pressure Measuring Device

NASA Technical Reports Server (NTRS)

Hum, L.; Cole, C. E.

1973-01-01

Design and performance of a blood pressure recording device for pediatric use are reported. A strain gage transducer with a copper-beryllium strip as force sensing element is used to monitor skin movements and to convert them into electrical signals proportional to those displacements. Experimental tests with this device in recording of force developed above the left femoral artery of a dog accurately produced a blood pressure curve.

The acute toxicity of inhaled beryllium metal in rats

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

Haley, P.J.; Finch, G.L.; Hoover, M.D.

1990-01-01

The authors exposed rats once by nose only for 50 min to a mean concentration of 800 [mu]g/m[sup 3] of beryllium metal to characterize the acute toxic effects within the lung. Histological changes within the lung and enzyme changes within bronchoalveolar lavage (BAL) fluid were evaluated at 3, 7, 10, 14, 31, 59, 115, and 171 days postexposure (dpe). Beryllium metal-exposed rats developed acute, necrotizing, hemorrhagic, exudative pneumonitis and intraalveolar fibrosis that peaked at 14 dpe. By 31 dpe, inflammatory lesions were replaced by minimal interstitial and intraalveolar fibrosis. Necrotizing inflammation was observed again at 59 dpe which progressed tomore » chronic-active inflammation by 115 dpe. Low numbers of diffusely distributed lymphocytes were also present but they were not associated with granulomas as is observed in beryllium-induced disease in man. Lymphocytes were not elevated in BAL samples collected from beryllium-exposed rats at any time after exposure. Lactate dehydrogenase (LDH), [beta]-glucuronidase, and protein levels were elevated in BAL fluid from 3 through 14 dpe but returned to near normal levels by 31 dpe. LDH increased once again at 59 dpe and remained elevated at 171 dpe. [beta]-Glucuronidase and protein levels were slightly, but not significantly, elevated from 31 through 171 dpe.« less

The microstructure and microhardness of friction stir welded dissimilar copper/Al-5% Mg alloys

NASA Astrophysics Data System (ADS)

Kalashnikova, T. A.; Shvedov, M. A.; Vasilyev, P. A.

2017-12-01

A friction stir welded joint between copper and aluminum alloy has been investigated and characterized for the microstructure and microhardness number distribution. The microstructural evolution of the joint is studied using optical microscopy and microhardness. The mechanical characteristics in structural zones of FSW joints are determined by Vickers microhardness measurements. Samples were cut across the cross section. It is shown that intermetallic Cu/Al particles are formed at interfaces. The intermetallics microhardness in the dissimilar aluminum/cooper FSW joint differs from that of the joint produced by fusion welding. The grain structures obtained in different dissimilar joint zones are examined.

Evolution of Microstructure in Brazed Joints of Austenitic-Martensitic Stainless Steel with Pure Silver Obtained with Ag-27Cu-5Sn Brazing Filler Material

NASA Astrophysics Data System (ADS)

Gangadharan, S.; Sivakumar, D.; Venkateswaran, T.; Kulkarni, Kaustubh

2016-12-01

Brazing of an austenitic-martensitic stainless steel (AMSS) with pure silver was carried out at 1053 K, 1073 K, and 1093 K (780 °C, 800 °C, and 820 °C) with Ag-27Cu-5Sn (wt pct) as brazing filler material (BFM). Wettability of the liquid BFM over base AMSS surface was found to be poor. Application of nickel coating to the steel was observed to enhance the wettability and to enable the formation of a good bond between BFM and the steel. The mechanism responsible for enhanced metallurgical bonding of the BFM with AMSS in the presence of nickel coating was explained based on diffusional interactions and uphill diffusion of iron, chromium and nickel observed in the brazed microstructure. Good diffusion-assisted zone was observed to form on silver side at all three temperatures. Four phases were encountered within the joint including silver solid solution, copper solid solution, Cu3Sn intermetallic and Ni-Fe solid solution. The Cu3Sn intermetallic was present in small amounts in the joints brazed at 1053 K and 1073 K (780 °C and 800 °C). The joint formed at 1093 K (820 °C) exhibited the absence of Cu3Sn, fewer defects and larger diffusion-assisted zone. Hardness of base AMSS was found to reduce during brazing due to austenite reversion and post-brazing sub-zero treatment for 2.5 hours was found suitable to recover the hardness.

High-temperature annealing of proton irradiated beryllium – A dilatometry-based study

DOE PAGES

Simos, Nikolaos; Elbakhshwan, Mohamed; Zhong, Zhong; ...

2016-04-07

S—200 F grade beryllium has been irradiated with 160 MeV protons up to 1.2 10 20 cm –2 peak fluence and irradiation temperatures in the range of 100–200 °C. To address the effect of proton irradiation on dimensional stability, an important parameter in its consideration in fusion reactor applications, and to simulate high temperature irradiation conditions, multi-stage annealing using high precision dilatometry to temperatures up to 740 °C were conducted in air. X-ray diffraction studies were also performed to compliment the macroscopic thermal study and offer a microscopic view of the irradiation effects on the crystal lattice. The primary objectivemore » was to qualify the competing dimensional change processes occurring at elevated temperatures namely manufacturing defect annealing, lattice parameter recovery, transmutation 4He and 3H diffusion and swelling and oxidation kinetics. Further, quantification of the effect of irradiation dose and annealing temperature and duration on dimensional changes is sought. Here, the study revealed the presence of manufacturing porosity in the beryllium grade, the oxidation acceleration effect of irradiation including the discontinuous character of oxidation advancement, the effect of annealing duration on the recovery of lattice parameters recovery and the triggering temperature for transmutation gas diffusion leading to swelling.« less

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.

Case report: heavy metal burden presenting as Bartter syndrome.

PubMed

Crinnion, Walter J; Tran, Jessica Q

2010-12-01

Maternal transfer of heavy metals during fetal development or lactation possibly contributed to the clinical manifestations of Bartter syndrome and developmental delay in the offspring. An 11-month-old child diagnosed with Bartter syndrome and failure to thrive was treated concurrently for elevated metal burden while he was undergoing standard medical interventions. Treatment with body-weight doses of meso-2,3-dimercaptosuccinic acid (DMSA) reduced the body burden of lead, beryllium, copper, mercury, and cadmium at the three- and sixth-month follow-up tests. During the course of the six-month treatment, the patient gained 2.4 kg (5.2 lb) and grew approximately 9.5 cm (3.75 in). His weight shifted from significantly below the 5th percentile in weight to within the 5th percentile, and from below the 5th to within the 10th percentile for length. The child's acquisition of lead, beryllium, and copper correspond to his mother's history of stained glass assembly and occurred during fetal development or lactation, since there were no other identifiable sources that could have contributed to the heavy metal burden. Tests for known genetic mutations leading to Bartter syndrome were all negative. This case report highlights the potential benefit of DMSA for treatment of heavy metal body burden in infants who present with Bartter syndrome.

Detection of beryllium treatment of natural sapphires by NRA

NASA Astrophysics Data System (ADS)

Gutiérrez, P. C.; Ynsa, M.-D.; Climent-Font, A.; Calligaro, T.

2010-06-01

Since the 1990's, artificial treatment of natural sapphires (Al 2O 3 crystals coloured by impurities) by diffusion of beryllium at high temperature has become a growing practice. This process permits to enhance the colour of these gemstones, and thus to increase their value. Detection of such a treatment - diffusion of tens of μg/g of beryllium in Al 2O 3 crystals - is usually achieved using high sensitivity techniques like laser-ablation inductively coupled plasma mass spectrometry (LA-ICP/MS) or laser-induced breakdown spectrometry (LIBS) which are unfortunately micro-destructive (leaving 50-100-μm diameter craters on the gems). The simple and non-destructive alternative method proposed in this work is based on the nuclear reaction 9Be(α, nγ) 12C with an external helium ion beam impinging on the gem directly placed in air. The 4439 keV prompt γ-ray tagging Be atoms are detected with a high efficiency bismuth germanate scintillator. Beam dose is monitored using the 2235 keV prompt γ-ray produced during irradiation by the aluminium of the sapphire matrix through the 27Al(α, pγ) 30Si nuclear reaction. The method is tested on a series of Be-treated sapphires previously analyzed by LA-ICP/MS to determine the optimal conditions to obtain a peak to background appropriate to reach the required μg/g sensitivity. Using a 2.8-MeV external He beam and a beam dose of 200 μC, beryllium concentrations from 5 to 16 μg/g have been measured in the samples, with a detection limit of 1 μg/g.

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.

Use of polarized radiation for increasing the sensitivity of multielement x-ray fluorescence analysis

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

Ter-Saakov, A.A.; Glebov, M.V.

1985-10-01

An experimental x-ray fluorescence analysis facility has been developed using polarized radiation. A modernized small-sized REIS-I emitter is used as the x-ray genertor. Its characteristics are: a straight-through drift tube with a copper, molybdenum, or silver anode; and a controlled working voltage from 0 to 45 kV. The thickness of the inlet beryllium window is 100 um. Experiments were carried out on the facility on the optimization of fluorescence excitation conditions of biological samples. The investigations conducted of the dosimetric and spectral characteristics of the BS-1, BS-3, and BKh-7 x-ray tubes with copper, silver, and molybdenum anodes have shown thatmore » for the analysis in samples of biogenic elements, it is most efficient to use the BKh-7 and BS-1 tubes with a copper anode.« less

Solid Freeform Fabrication Symposium Proceedings Held in Austin, Texas on August 9-11, 1993

DTIC Science & Technology

1993-09-01

between the accuracy and the size of the geometric description. Highly non-linear surfaces, such as those that comprise turbine blades , manifolds...flange. The fan blades were modeled using different surfacing techniques. Seven blades are then combined with the rotor to make the completed fan. Figure...successfully cast in aluminum, titanium , beryllium-copper, and stainless steel, with RMS surface finish as low as 1 micrometer, without any subsequent

Epidemiological and experimental aspects of metal carcinogenesis: physicochemical properties, kinetics, and the active species.

PubMed Central

Magos, L

1991-01-01

The carcinogenic properties of selected metals and their compounds are reviewed to provide a useful reference for existing knowledge on relationships between physical and chemical forms, kinetics and carcinogenic potential and between epidemiology, bioassays, and short-term tests. Extensive consideration is given to arsenic, beryllium, cadmium, chromium, lead, and nickel. Other metals such as antimony, cobalt, copper, iron, manganese, selenium, and zinc are discussed briefly. PMID:1821370

Microstructural Characteristics and Mechanical Properties of an Electron Beam-Welded Ti/Cu/Ni Joint

NASA Astrophysics Data System (ADS)

Zhang, Feng; Wang, Ting; Jiang, Siyuan; Zhang, Binggang; Feng, Jicai

2018-04-01

Electron beam welding experiments of TA15 titanium alloy to GH600 nickel superalloy with and without a copper sheet interlayer were carried out. Surface appearance, microstructure and phase constitution of the joint were examined by optical microscopy, scanning electron microscopy and x-ray diffraction analysis. Mechanical properties of Ti/Ni and Ti/Cu/Ni joint were evaluated based on tensile strength and microhardness tests. The results showed that cracking occurred in Ti/Ni electron beam weldment for the formation of brittle Ni-Ti intermetallics, while a crack-free electron beam-welded Ti/Ni joint can be obtained by using a copper sheet as filler metal. The addition of copper into the weld affected the welding metallurgical process of the electron beam-welded Ti/Ni joint significantly and was helpful for restraining the formation of Ti-Ni intermetallics in Ti/Ni joint. The microstructure of the weld was mainly characterized by a copper-based solid solution and Ti-Cu interfacial intermetallic compounds. Ti-Ni intermetallic compounds were almost entirely suppressed. The hardness of the weld zone was significantly lower than that of Ti/Ni joint, and the tensile strength of the joint can be up to 282 MPa.

Microstructural Characteristics and Mechanical Properties of an Electron Beam-Welded Ti/Cu/Ni Joint

NASA Astrophysics Data System (ADS)

Zhang, Feng; Wang, Ting; Jiang, Siyuan; Zhang, Binggang; Feng, Jicai

2018-05-01

Electron beam welding experiments of TA15 titanium alloy to GH600 nickel superalloy with and without a copper sheet interlayer were carried out. Surface appearance, microstructure and phase constitution of the joint were examined by optical microscopy, scanning electron microscopy and x-ray diffraction analysis. Mechanical properties of Ti/Ni and Ti/Cu/Ni joint were evaluated based on tensile strength and microhardness tests. The results showed that cracking occurred in Ti/Ni electron beam weldment for the formation of brittle Ni-Ti intermetallics, while a crack-free electron beam-welded Ti/Ni joint can be obtained by using a copper sheet as filler metal. The addition of copper into the weld affected the welding metallurgical process of the electron beam-welded Ti/Ni joint significantly and was helpful for restraining the formation of Ti-Ni intermetallics in Ti/Ni joint. The microstructure of the weld was mainly characterized by a copper-based solid solution and Ti-Cu interfacial intermetallic compounds. Ti-Ni intermetallic compounds were almost entirely suppressed. The hardness of the weld zone was significantly lower than that of Ti/Ni joint, and the tensile strength of the joint can be up to 282 MPa.

Hydrogen isotope retention in beryllium for tokamak plasma-facing applications

NASA Astrophysics Data System (ADS)

Anderl, R. A.; Causey, R. A.; Davis, J. W.; Doerner, R. P.; Federici, G.; Haasz, A. A.; Longhurst, G. R.; Wampler, W. R.; Wilson, K. L.

Beryllium has been used as a plasma-facing material to effect substantial improvements in plasma performance in the Joint European Torus (JET), and it is planned as a plasma-facing material for the first wall (FW) and other components of the International Thermonuclear Experimental Reactor (ITER). The interaction of hydrogenic ions, and charge-exchange neutral atoms from plasmas, with beryllium has been studied in recent years with widely varying interpretations of results. In this paper we review experimental data regarding hydrogenic atom inventories in experiments pertinent to tokamak applications and show that with some very plausible assumptions, the experimental data appear to exhibit rather predictable trends. A phenomenon observed in high ion-flux experiments is the saturation of the beryllium surface such that inventories of implanted particles become insensitive to increased flux and to continued implantation fluence. Methods for modeling retention and release of implanted hydrogen in beryllium are reviewed and an adaptation is suggested for modeling the saturation effects. The TMAP4 code used with these modifications has succeeded in simulating experimental data taken under saturation conditions where codes without this feature have not. That implementation also works well under more routine conditions where the conventional recombination-limited release model is applicable. Calculations of tritium inventory and permeation in the ITER FW during the basic performance phase (BPP) using both the conventional recombination model and the saturation effects assumptions show a difference of several orders of magnitude in both inventory and permeation rate to the coolant.

ARC: A compact, high-field, disassemblable fusion nuclear science facility and demonstration power plant

NASA Astrophysics Data System (ADS)

Sorbom, Brandon; Ball, Justin; Palmer, Timothy; Mangiarotti, Franco; Sierchio, Jennifer; Bonoli, Paul; Kasten, Cale; Sutherland, Derek; Barnard, Harold; Haakonsen, Christian; Goh, Jon; Sung, Choongki; Whyte, Dennis

2014-10-01

The Affordable, Robust, Compact (ARC) reactor conceptual design aims to reduce the size, cost, and complexity of a combined Fusion Nuclear Science Facility (FNSF) and demonstration fusion pilot power plant. ARC is a 270 MWe tokamak reactor with a major radius of 3.3 m, a minor radius of 1.1 m, and an on-axis magnetic field of 9.2 T. ARC has Rare Earth Barium Copper Oxide (REBCO) superconducting toroidal field coils with joints to allow disassembly, allowing for removal and replacement of the vacuum vessel as a single component. Inboard-launched current drive of 25 MW LHRF power and 13.6 MW ICRF power is used to provide a robust, steady state core plasma far from disruptive limits. ARC uses an all-liquid blanket, consisting of low pressure, slowly flowing Fluorine Lithium Beryllium (FLiBe) molten salt. The liquid blanket acts as a working fluid, coolant, and tritium breeder, and minimizes the solid material that can become activated. The large temperature range over which FLiBe is liquid permits blanket operation at 800-900 K with single phase fluid cooling and allows use of a high-efficiency Brayton cycle for electricity production in the secondary coolant loop.

Development of Methods for Low Temperature Diffusion Bonding.

DTIC Science & Technology

1987-09-01

Hazlett, T. H., " High Strength Low Temperature Bonding of Beryllium and Other Metals," Welding Journal, 60(11), pp. 301-s to 310-s, 1970. 12. 1986 Annual...34CIPLU’q *flBQ~ P 0.(4 ".Oq’J 4 Low Temperature , Methods for Diffusion Rl ,’..’S olid deveoped ~’~ ~ ’State Bonding, or Diffusion Welding An apparatus lor...low t’empeaur R~u on’ nding of dissimilar metals has been develped.Experiments varying the bonding temperature at constant pressure and time were

Air National Guard Installation Restoration Protram. Site Investigation Report: Georgia Air National Guard, Savannah, Georgia

DTIC Science & Technology

1992-01-01

except TPH, which was detected at 0.06 mg/l in Monitor Well 01-MW-02. Some metals (arsenic, cadmium , chromium, lead, silver, and zinc ) were detected at...extraction. Trace quantities of some priority pollutant metals were detected in the surface water samples. Arsenic, cadmium , and zinc were detected at...storage tank. TPH was detected in all five groundwater samples. Arsenic, beryllium, cadmium , chromium, copper, lead, nickel, silver, and zinc were also

Particle clearance and histopathology in lungs of C3H/HeJ mice administered beryllium/copper alloy by intratracheal instillation.

PubMed

Benson, J M; Holmes, A M; Barr, E B; Nikula, K J; March, T H

2000-08-01

Beryllium/copper (BeCu) alloys are commonly used in the electronics, automotive, consumer, defense, and aerospace industries. Some individuals exposed occupationally to BeCu alloys have developed chronic beryllium disease. However, little is known of the toxicity and fate of BeCu alloys in the respiratory tract. To begin to address this question, we investigated the pulmonary toxicity and clearance of BeCu alloy (2% Be; 98% Cu) in mice. Groups of 40 female C3H/HeJ mice were administered 12.5, 25, and 100 microg BeCu alloy or 2 and 8 microg Be metal by intratracheal instillation. Mice were sacrificed at 1 h and 1, 7, 14, and 28 days postinstillation. Left lungs were evaluated for histopathological change. Right lungs were analyzed for Be and Cu content. Twenty-five percent of the high-dose BeCu mice and 7.5% of the mid-dose BeCu mice died within 24 h of dosing. Acute pulmonary lesions included acute alveolitis and interstitial inflammation. Type II epithelial cell hyperplasia and centriacinar fibrosis were present by 7 days after dosing. Lesions persisted through 28 days after instillation. No lesions attributable to alloy exposure were present in liver or kidney. Be metal instillation caused no deaths and minimal pulmonary changes over the time studied, indicating that the pulmonary lesions were due to Cu rather than Be. Cu cleared the lung with a half-time of 0. 5-2 days. Be cleared with a half-time of several weeks or longer. Results of this study suggest that exposure to BeCu alloy is more acutely toxic to lung than Be metal. The results of tissue analyses also indicate that, while the Cu component of the alloy clears the lung rapidly, Be is retained and may accumulate upon repeated exposure.

Diffuse emission and control of copper in urban surface runoff.

PubMed

Boller, M A; Steiner, M

2002-01-01

Copper washed off from roofs and roads is considered to be a major contribution to diffuse copper pollution of urban environments. In order to guarantee sustainable protection of soils and water, the long-term strategy is to avoid or replace copper containing materials on roofs and fagades. Until achievement of this goal, a special adsorber system is suggested to control the diffuse copper fluxes by retention of copper by a mixture of granulated iron-hydroxide (GEH) and calcium carbonate. Since future stormwater runoff concepts are based on decentralised runoff infiltration into the underground, solutions are proposed which provide for copper retention in infiltration sites using GEH adsorption layers. The example of a large copper façade of which the runoff is treated in an adsorption trench reveals the first full-scale data on façade runoff and adsorber performance. During the first year of investigation average façade runoff concentrations in the range of 1-10 mg Cu/l are reduced by 96-99% in the adsorption ditch.

Inorganic dust pneumonias: the metal-related parenchymal disorders.

PubMed Central

Kelleher, P; Pacheco, K; Newman, L S

2000-01-01

In recent years the greatest progress in our understanding of pneumoconioses, other than those produced by asbestos, silica, and coal, has been in the arena of metal-induced parenchymal lung disorders. Inhalation of metal dusts and fumes can induce a wide range of lung pathology, including airways disorders, cancer, and parenchymal diseases. The emphasis of this update is on parenchymal diseases caused by metal inhalation, including granulomatous disease, giant cell interstitial pneumonitis, chemical pneumonitis, and interstitial fibrosis, among others. The clinical characteristics, epidemiology, and pathogenesis of disorders arising from exposure to aluminum, beryllium, cadmium, cobalt, copper, iron, mercury, and nickel are presented in detail. Metal fume fever, an inhalation fever syndrome attributed to exposure to a number of metals, is also discussed. Advances in our knowledge of antigen-specific immunologic reactions in the lung are particularly evident in disorders secondary to beryllium and nickel exposure, where immunologic mechanisms have been well characterized. For example, current evidence suggests that beryllium acts as an antigen, or hapten, and is presented by antigen-presenting cells to CD4+ T cells, which possess specific surface antigen receptors. Other metals such as cadmium and mercury induce nonspecific damage, probably by initiating production of reactive oxygen species. Additionally, genetic susceptibility markers associated with increased risk have been identified in some metal-related diseases such as chronic beryllium disease and hard metal disease. Future research needs include development of biologic markers of metal-induced immunologic disease, detailed characterization of human exposure, examination of gene alleles that might confer risk, and association of exposure data with that of genetic susceptibility. PMID:10931787

Kiln emissions and potters' exposures.

PubMed

Hirtle, B; Teschke, K; van Netten, C; Brauer, M

1998-10-01

Some ten thousand British Columbia potters work in small private studios, cooperative facilities, educational institutions, or recreation centers. There has been considerable concern that this diffuse, largely unregulated activity may involve exposures to unacceptable levels of kiln emissions. Pottery kiln emissions were measured at 50 sites--10 from each of 5 categories: professional studios, recreation centers, elementary schools, secondary schools, and colleges. Area monitoring was done 76 cm from firing kilns and 1.6 m above the floor to assess breathing zone concentrations of nitrogen dioxide, carbon monoxide, sulfur dioxide, fluorides, aldehydes, aluminum, antimony, arsenic, barium, beryllium, boron, cadmium, chromium, cobalt, copper, gold, iron, lead, lithium, magnesium, manganese, mercury, nickel, selenium, silver, vanadium, and zinc. Personal exposures to the same metals were measured at 24 sites. Almost all measured values were well below permissible concentrations for British Columbia work sites and American Conference of Governmental Industrial Hygienists (ACGIH) threshold limit values (TLVs) with the following two exceptions. A single firing duration (495 minute) acrolein measurement adjacent to an electric kiln (0.109 ppm) exceeded these guidelines. One 15-minute sulfur dioxide measurement collected adjacent to a gas kiln (5.7 ppm) exceeded the ACGIH short-term exposure limit. The fact that concentrations in small, ventilated kiln rooms ranked among the highest measured gives rise to concern that unacceptable levels of contamination may exist where small kiln rooms remain unventilated. Custom designed exhaust hoods and industrial heating, ventilating, and air-conditioning systems were the most effective ventilation strategies. Passive diffusion and wall/window fans were least effective.

Metal allergens of growing significance: epidemiology, immunotoxicology, strategies for testing and prevention.

PubMed

Forte, Giovanni; Petrucci, Francesco; Bocca, Beatrice

2008-09-01

Metal-induced allergic contact dermatitis (ACD) is expressed in a wide range of cutaneous reactions following dermal and systemic exposure to products such as cosmetics and tattoos, detergents, jewellery and piercing, leather tanning, articular prostheses and dental implants. Apart from the well known significance of nickel in developing ACD, other metals such as aluminium, beryllium, chromium, cobalt, copper, gold, iridium, mercury, palladium, platinum, rhodium and titanium represented emerging causes of skin hypersensitivity. Despite the European Union directives that limit the total nickel content in jewellery alloys, the water soluble chromium (VI) in cement, and metals banned in cosmetics, the diffusion of metal-induced ACD remained quite high. On this basis, a review on the epidemiology of metal allergens, the types of exposure, the skin penetration, the immune response, and the protein interaction is motivated. Moreover, in vivo and in vitro tests for the identification and potency of skin-sensitizing metals are here reviewed in a risk assessment framework for the protection of consumer's health. Avenues for ACD prevention and therapy such as observance of maximum allowable metal levels, optimization of metallurgic characteristics, efficacy of chelating agents and personal protection are also discussed.

Introduction to Shaped Charges

DTIC Science & Technology

2007-03-01

Figure 144. Late time collapse of a hemispherical depleted uranium liner. COPPER 430MM(17") LEAD-TIN EUTECTIC Figure 145. Comparison between...46 Figure 91. Setup for diffusion bonding of copper- nickel assemblies, temperature is 982 °C, time is 1–3 hr, argon atmosphere...46 Figure 92. Diffusion-bonded alternately layered copper- nickel

Development of lightweight aluminum hollowcore solar cell array technology

NASA Technical Reports Server (NTRS)

Carlson, J. A.

1971-01-01

A baseline configuration for a three section folding array, with retraction capability, was developed which would utilize electroformed aluminum hollowcore substrates and beryllium frames. The three section array was not fabricated because of difficulties with impurities in the aluminum electroforming bath. A procedure was developed for etching the copper mandrel from virtually any size of aluminum hollowcore panel in approximately one hour. Procedures were developed for analyzing the content of peroxide, water, total aluminum, and lithium-aluminum-hydride in an aluminum electroforming solution.

NEW SERDP Project: Copper- Beryllium Alternatives Alloys Development

DTIC Science & Technology

2011-02-10

ChemistryRefining Lath Martensite: Ms≥200°C Nickel: Cleavage Resistance Cobalt: SRO Recovery Resistance Chromium : Corrosion Resistance σuts > 280 ksi σys...230 ksi (Cr, Mo, V, Fe)2 C Avoid Fe3C, M6C, M7C3, M23C6 ~ 15-5 PH Chromium Partitioning Into Oxide Film epp and icrit Chromium , Molybdenum, Vandium...Primary exposure risk is Be dust or fume inhalation – ~ 4-10% of population show sensitivity to Be – Allergic type reaction in lungs creating fluid

Transient liquid phase bonding of titanium-, iron- and nickel-based alloys

NASA Astrophysics Data System (ADS)

Rahman, A. H. M. Esfakur

The operating temperature of land-based gas turbines and jet engines are ever-increasing to increase the efficiency, decrease the emissions and minimize the cost. Within the engines, complex-shaped parts experience extreme temperature, fatigue and corrosion conditions. Ti-based, Ni-based and Fe-based alloys are commonly used in gas turbines and jet engines depending on the temperatures of different sections. Although those alloys have superior mechanical, high temperature and corrosion properties, severe operating conditions cause fast degradation and failure of the components. Repair of these components could reduce lifecycle costs. Unfortunately, conventional fusion welding is not very attractive, because Ti reacts very easily with oxygen and nitrogen at high temperatures, Ni-based superalloys show heat affected zone (HAZ) cracking, and stainless steels show intergranular corrosion and knife-line attack. On the other hand, transient liquid phase (TLP) bonding method has been considered as preferred joining method for those types of alloys. During the initial phase of the current work commercially pure Ti, Fe and Ni were diffusion bonded using commercially available interlayer materials. Commercially pure Ti (Ti-grade 2) has been diffusion bonded using silver and copper interlayers and without any interlayer. With a silver (Ag) interlayer, different intermetallics (AgTi, AgTi2) appeared in the joint centerline microstructure. While with a Cu interlayer eutectic mixtures and Ti-Cu solid solutions appeared in the joint centerline. The maximum tensile strengths achieved were 160 MPa, 502 MPa, and 382 MPa when Ag, Cu and no interlayers were used, respectively. Commercially pure Fe (cp-Fe) was diffusion bonded using Cu (25 m) and Au-12Ge eutectic interlayer (100 microm). Cu diffused predominantly along austenite grain boundaries in all bonding conditions. Residual interlayers appeared at lower bonding temperature and time, however, voids were observed in the joint centerline at higher joining temperature and time. Dispersed Au-rich particles were observed in the base metal near interface. The highest ultimate tensile strengths obtained for the bonded Fe were 291+/-2 MPa using a Cu interlayer at 1030°C for 10 h and 315+/-4 MPa using a Au-12Ge interlayer at 950°C for 15 h. Commercially pure Ni (cp-Ni) was diffusion bonded using a Al, Au-12Ge or Cu interlayer. The formation of intermetallics could not be avoided when Al interlayer was used. Even though no intermetallics were obtained with Au-12Ge or Cu interlayer, appreciable strength of the joint was not found. Next, the simple bonding systems were modeled numerically. It is hoped that the simple models can be extended for higher order alloys. The modeling of TLP joint means to come up with a mathematical model which can predict the concentration profiles of diffusing species. The concentration dependence of diffusivity in a multi-component diffusion system makes it complicated to predict the concentration profiles of diffusing species. The so-called chemical diffusivity can be expressed as a function of thermodynamic and kinetic data. DICTRA software can calculate the concentration profiles using appropriate mobility and thermodynamic data. It can also optimize the diffusivity data using experimental diffusivity data. Then the optimized diffusivity data is stored as mobility data which is a linear function of temperature. In this work, diffusion bonding of commercially pure Ni using Cu interlayers is reported. The mobility parameters of Ni-Cu alloy binary systems were optimized using DICTRA/Thermocalc software from the available self-, tracer and chemical diffusion coefficients. The optimized mobility parameters were used to simulate concentration profiles of Ni-Cu diffusion joints using DICTRA/Thermocalc software. The calculated and experimental concentration profiles agreed well at 1100 °C. This method could not be extended for higher order alloys because of the lack of appropriate thermodynamic and kinetic database. In the third phase industrially important alloys such as SS 321, Inconel 718 and Ti-6Al-4V were diffusion bonded. Diffusion bonded SS 321 with Au-12Ge interlayer provided the best microstructure when bonded in either vacuum or argon at 1050°C for 20 h and cooled in air. The maximum strength obtained of the joint was 387+/-4 MPa bonded in vacuum at 1050°C for 20 h and cooled in air. The microstructure of joint centerline of diffusion bonded Inconel 718 using Au-12Ge interlayer at 1050°C for 15 h and cooled in air consisted of residual interlayer (1.3-2.5 microm). The residual interlayer was disappeared by increasing the bonding time by 5 h, however, pores appeared in the joint centerline. As a result, the strength obtained for bonded Inconel 718 was much lower than that of the base alloy. The joint centerline microstructure of bonded Ti-6Al-4V using Cu interlayer was free of intermetallics and solid solution of Cu and base alloy. The strength of the joint is yet to be determined.

Modeling of batch sorber system: kinetic, mechanistic, and thermodynamic modeling

NASA Astrophysics Data System (ADS)

Mishra, Vishal

2017-10-01

The present investigation has dealt with the biosorption of copper and zinc ions on the surface of egg-shell particles in the liquid phase. Various rate models were evaluated to elucidate the kinetics of copper and zinc biosorptions, and the results indicated that the pseudo-second-order model was more appropriate than the pseudo-first-order model. The curve of the initial sorption rate versus the initial concentration of copper and zinc ions also complemented the results of the pseudo-second-order model. Models used for the mechanistic modeling were the intra-particle model of pore diffusion and Bangham's model of film diffusion. The results of the mechanistic modeling together with the values of pore and film diffusivities indicated that the preferential mode of the biosorption of copper and zinc ions on the surface of egg-shell particles in the liquid phase was film diffusion. The results of the intra-particle model showed that the biosorption of the copper and zinc ions was not dominated by the pore diffusion, which was due to macro-pores with open-void spaces present on the surface of egg-shell particles. The thermodynamic modeling reproduced the fact that the sorption of copper and zinc was spontaneous, exothermic with the increased order of the randomness at the solid-liquid interface.

Control of the Structure of Diffusion Layer in Carbon Steels Under Nitriding with Preliminary Deposition of Copper Oxide Catalytic Films

NASA Astrophysics Data System (ADS)

Petrova, L. G.; Aleksandrov, V. A.; Malakhov, A. Yu.

2017-07-01

The effect of thin films of copper oxide deposited before nitriding on the phase composition and the kinetics of growth of diffusion layers in carbon steels is considered. The process of formation of an oxide film involves chemical reduction of pure copper on the surface of steel specimens from a salt solution and subsequent oxidation under air heating. The oxide film exerts a catalytic action in nitriding of low- and medium-carbon steels, which consists in accelerated growth of the diffusion layer, the nitride zone in the first turn. The kinetics of the nitriding process and the phase composition of the layer are controlled by the thickness of the copper oxide precursor, i.e., the deposited copper film.

Low temperature thermal conductivity of alloys used in cryogenic coaxial cables

NASA Astrophysics Data System (ADS)

Kushino, Akihiro; Kasai, Soichi

2014-03-01

We have developed thin seamless coaxial cables applied for readout in low temperature experiments below liquid helium temperature. Stainless steel employed as the center and outer electrical conductors of the coaxial cable has adequately low thermal conductivity compared to pure metals and can be used when heat penetration into low temperature stages through cables should be lowered however it has large electrical resistivity which can disturb sensitive measurements. Superconducting NbTi alloy has good performance with rather low thermal conductivity and high electrical conductivity. Meanwhile coaxial cables using normal conducting copper alloys such as cupro-nickel, brass, beryllium-copper, phosphor-bronze are advantageous with their good electrical, thermal and cost performances. We investigated thermal conductivity of such alloys after the drawing process into coaxial cables, and compared to expected values without drawing.

Factors that Affect the Content of Cadmium, Nickel, Copper and Zinc in Tissues of the Knee Joint.

PubMed

Roczniak, Wojciech; Brodziak-Dopierała, Barbara; Cipora, Elżbieta; Jakóbik-Kolon, Agata; Kluczka, Joanna; Babuśka-Roczniak, Magdalena

2017-08-01

Osteoarthritis causes the degradation of the articular cartilage and periarticular bones. Trace elements influence the growth, development and condition of the bone tissue. Changes to the mineral composition of the bone tissue can cause degenerative changes and fractures. The aim of the research was to determine the content of cadmium (Cd), nickel (Ni), copper (Cu) and zinc (Zn) in the tibia, the femur and the meniscus in men and women who underwent a knee replacement surgery. Samples were collected from 50 patients, including 36 women and 14 men. The determination of trace elements content were performed by ICP-AES method, using Varian 710-ES. Average concentration in the tissues of the knee joint teeth amounted for cadmium 0.015, nickel 0.60, copper 0.89 and zinc 80.81 mg/kg wet weight. There were statistically significant differences in the content of cadmium, copper and zinc in different parts of the knee joint. There were no statistically significant differences in the content of cadmium, nickel, copper and zinc in women and men in the examined parts of the knee joint. Among the elements tested, copper and nickel showed a high content in the connective tissue (the meniscus) compared to the bone tissue (the tibia and the femur).

Joining of alumina via copper/niobium/copper interlayers

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

Marks, Robert A.; Chapman, Daniel R.; Danielson, David T.

2000-03-15

Alumina has been joined at 1150 degrees C and 1400 degrees C using multilayer copper/niobium/copper interlayers. Four-point bend strengths are sensitive to processing temperature, bonding pressure, and furnace environment (ambient oxygen partial pressure). Under optimum conditions, joints with reproducibly high room temperature strengths (approximately equal 240 plus/minus 20 MPa) can be produced; most failures occur within the ceramic. Joints made with sapphire show that during bonding an initially continuous copper film undergoes a morphological instability, resulting in the formation of isolated copper-rich droplets/particles at the sapphire/interlayer interface, and extensive regions of direct bonding between sapphire and niobium. For optimized aluminamore » bonds, bend tests at 800 degrees C-1100 degrees C indicate significant strength is retained; even at the highest test temperature, ceramic failure is observed. Post-bonding anneals at 1000 degrees C in vacuum or in gettered argon were used to assess joint stability and to probe the effect of ambient oxygen partial pressure on joint characteristics. Annealing in vacuum for up to 200 h causes no significant decrease in room temperature bend strength or change in fracture path. With increasing anneal time in a lower oxygen partial pressure environment, the fracture strength decreases only slightly, but the fracture path shifts from the ceramic to the interface.« less

CuCrZr alloy microstructure and mechanical properties after hot isostatic pressing bonding cycles

NASA Astrophysics Data System (ADS)

Frayssines, P.-E.; Gentzbittel, J.-M.; Guilloud, A.; Bucci, P.; Soreau, T.; Francois, N.; Primaux, F.; Heikkinen, S.; Zacchia, F.; Eaton, R.; Barabash, V.; Mitteau, R.

2014-04-01

ITER first wall (FW) panels are a layered structure made of the three following materials: 316L(N) austenitic stainless steel, CuCrZr alloy and beryllium. Two hot isostatic pressing (HIP) cycles are included in the reference fabrication route to bond these materials together for the normal heat flux design supplied by the European Union (EU). This reference fabrication route ensures sufficiently good mechanical properties for the materials and joints, which fulfil the ITER mechanical specifications, but often results in a coarse grain size for the CuCrZr alloy, which is not favourable, especially, for the thermal creep properties of the FW panels. To limit the abnormal grain growth of CuCrZr and make the ITER FW fabrication route more reliable, a study began in 2010 in the EU in the frame of an ITER task agreement. Two material fabrication approaches have been investigated. The first one was dedicated to the fabrication of solid CuCrZr alloy in close collaboration with an industrial copper alloys manufacturer. The second approach investigated was the manufacturing of CuCrZr alloy using the powder metallurgy (PM) route and HIP consolidation. This paper presents the main mechanical and microstructural results associated with the two CuCrZr approaches mentioned above. The mechanical properties of solid CuCrZr, PM CuCrZr and joints (solid CuCrZr/solid CuCrZr and solid CuCrZr/316L(N) and PM CuCrZr/316L(N)) are also presented.

Copper Gas Diffusers For Purging Line-Focus Laser Welds

NASA Technical Reports Server (NTRS)

Fonteyne, Steve L.; Hosking, Timothy J.; Shelley, D. Mark

1996-01-01

Modified flow diffusers built for inert-gas purging of welds made with 5-kW CO(2) lasers operating with line-focus optics in conduction mode instead of with point-focus optics in customary keyhole mode. Diffusers made of copper components brazed together, robust enough to withstand strong reflections of line-focused laser energy.

A passively-safe fusion reactor blanket with helium coolant and steel structure

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

Crosswait, Kenneth Mitchell

1994-04-01

Helium is attractive for use as a fusion blanket coolant for a number of reasons. It is neutronically and chemically inert, nonmagnetic, and will not change phase during any off-normal or accident condition. A significant disadvantage of helium, however, is its low density and volumetric heat capacity. This disadvantage manifests itself most clearly during undercooling accident conditions such as a loss of coolant accident (LOCA) or a loss of flow accident (LOFA). This thesis describes a new helium-cooled tritium breeding blanket concept which performs significantly better during such accidents than current designs. The proposed blanket uses reduced-activation ferritic steel asmore » a structural material and is designed for neutron wall loads exceeding 4 MW/m{sup 2}. The proposed geometry is based on the nested-shell concept developed by Wong, but some novel features are used to reduce the severity of the first wall temperature excursion. These features include the following: (1) A ``beryllium-joint`` concept is introduced, which allows solid beryllium slabs to be used as a thermal conduction path from the first wall to the cooler portions of the blanket. The joint concept allows for significant swelling of the beryllium (10 percent or more) without developing large stresses in the blanket structure. (2) Natural circulation of the coolant in the water-cooled shield is used to maintain shield temperatures below 100 degrees C, thus maintaining a heat sink close to the blanket during the accident. This ensures the long-term passive safety of the blanket.« less

Experimental investigations of tungsten inert gas assisted friction stir welding of pure copper plates

NASA Astrophysics Data System (ADS)

Constantin, M. A.; Boșneag, A.; Nitu, E.; Iordache, M.

2017-10-01

Welding copper and its alloys is usually difficult to join by conventional fusion welding processes because of high thermal diffusivity of the copper, alloying elements, necessity of using a shielding gas and a clean surface. To overcome this inconvenience, Friction Stir Welding (FSW), a solid state joining process that relies on frictional heating and plastic deformation, is used as a feasible welding process. In order to achieve an increased welding speed and a reduction in tool wear, this process is assisted by another one (WIG) which generates and adds heat to the process. The aim of this paper is to identify the influence of the additional heat on the process parameters and on the welding joint properties (distribution of the temperature, hardness and roughness). The research includes two experiments for the FSW process and one experiment for tungsten inert gas assisted FSW process. The outcomes of the investigation are compared and analysed for both welding variants. Adding a supplementary heat source, the plates are preheated and are obtain some advantages such as reduced forces used in process and FSW tool wear, faster and better plasticization of the material, increased welding speed and a proper weld quality.

Influence of multi-walled carbon nanotubes on melting temperature and microstructural evolution of Pb-free Sn-5Sb/Cu solder joint

NASA Astrophysics Data System (ADS)

Dele-Afolabi, T. T.; Azmah Hanim, M. A.; Norkhairunnisa, M.; Suraya, M. T.; Yusoff, H. M.

2017-09-01

In this study, the effects of multi-walled carbon nanotubes on the melting temperature and microstructural evolution of the Sn-5Sb/Cu joints are evaluated. Plain and carbon nanotubes (CNTs) reinforced Sn-5Sb solder systems with solder formulations Sn-5Sb, Sn-5Sb-0.01CNT, Sn-5Sb-0.05CNT and Sn-5Sb-0.1CNT were prepared through the powder metallurgy route and thereafter samples were subjected to thermal and microstructural evaluation. As retrieved from the DSC scans, a slight decline in the peak temperature was observed in the composite solders which is indicative of the CNTs role in exciting surface instability in the host Sn matrix. In order to prepare the solder joints and analyze the interfacial intermetallic compound (IMC) evolution, respective solder systems were placed on copper (Cu) substrate and subjected to both reflow soldering and isothermal aging (170°C) conditions. From the IMC thickness result, considerable retardation in the IMC layer growth was observed in the CNTs reinforced solder joints, especially the 0.05wt.% CNTs solder system owing to the inhibition of Sn atoms diffusion by reinforcement material.

Reaction layer formation at the graphite/copper-chromium alloy interface

NASA Technical Reports Server (NTRS)

Devincent, Sandra M.; Michal, Gary M.

1992-01-01

Sessile drop tests were used to obtain information about copper chromium alloys that suitably wet graphite. Characterization of graphite/copper-chromium alloy interfaces subjected to elevated temperatures were conducted using scanning electron micrography, energy dispersive spectroscopy, auger electron spectroscopy, and x ray diffraction analyses. These analyses indicate that during sessile drop tests conducted at 1130 C for one hour, copper alloys containing greater than 0.98 percent chromium form continuous reaction layers of approximately 10 micron thickness. The reaction layers adhere to the graphite surface. The copper wets the reaction layer to form a contact angle of 60 degrees or less. X ray diffraction results indicate that the reaction layer is chromium carbide. The kinetics of reaction layer formation were modelled in terms of bulk diffusion mechanisms. Reaction layer thickness is controlled initially by the diffusion of Cr out of Cu alloy and later by the diffusion of C through chromium carbide.

Reaction layer formation at the graphite/copper-chromium alloy interface

NASA Technical Reports Server (NTRS)

Devincent, Sandra M.; Michal, Gary M.

1993-01-01

Sessile drop tests were used to obtain information about copper chromium alloys that suitably wet graphite. Characterization of graphite/copper-chromium alloy interfaces subjected to elevated temperatures were conducted using scanning electron micrography, energy dispersive spectroscopy, Auger electron spectroscopy, and X-ray diffraction analyses. These analyses indicate that during sessile drop tests conducted at 1130 C for one hour, copper alloys containing greater than 0.98 percent chromium form continuous reaction layers of approximately 10 micron thickness. The reaction layers adhere to the graphite surface. The copper wets the reaction layer to form a contact angle of 60 degrees or less. X-ray diffraction results indicate that the reaction layer is chromium carbide. The kinetics of reaction layer formation were modelled in terms of bulk diffusion mechanisms. Reaction layer thickness is controlled initially by the diffusion of Cr out of Cu alloy and later by the diffusion of C through chromium carbide.

Copper diffusion in Ti Si N layers formed by inductively coupled plasma implantation

NASA Astrophysics Data System (ADS)

Ee, Y. C.; Chen, Z.; Law, S. B.; Xu, S.; Yakovlev, N. L.; Lai, M. Y.

2006-11-01

Ternary Ti-Si-N refractory barrier films of 15 nm thick was prepared by low frequency, high density, inductively coupled plasma implantation of N into TixSiy substrate. This leads to the formation of Ti-N and Si-N compounds in the ternary film. Diffusion of copper in the barrier layer after annealing treatment at various temperatures was investigated using time-of-flight secondary ion mass spectrometer (ToF-SIMS) depth profiling, X-ray diffractometer (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) and sheet resistance measurement. The current study found that barrier failure did not occur until 650 °C annealing for 30 min. The failure occurs by the diffusion of copper into the Ti-Si-N film to form Cu-Ti and Cu-N compounds. FESEM surface morphology and EDX show that copper compounds were formed on the ridge areas of the Ti-Si-N film. The sheet resistance verifies the diffusion of Cu into the Ti-Si-N film; there is a sudden drop in the resistance with Cu compound formation. This finding provides a simple and effective method of monitoring Cu diffusion in TiN-based diffusion barriers.

Diffusion at the boundary between the film and substrate upon the electrocrystallization of zinc on a copper substrate

NASA Astrophysics Data System (ADS)

Shtapenko, E. Ph.; Zabludovsky, V. A.; Dudkina, V. V.

2015-03-01

In this paper, we present the results of experimental investigations of the diffusion layer formed at the film-substrate interface upon the electrodeposition of zinc films on a copper substrate. The investigations have shown that, in the transient layer, the deposited metal is diffused into the material of the substrate. The depth of the diffusion layer and, consequently, the concentrations of the incorporated zinc atoms depend strongly on the conditions of electrocrystallization, which vary from 1.5 μm when using direct current to 4 μm when using direct current in combination with laser-stimulated deposition (LSD). The X-ray diffraction investigations of the transient layer at the film-substrate interface have shown that, upon electrocrystallization using pulsed current in rigid regimes with the application of the LSD, a CuZn2 phase is formed in the diffusion layer. This indicates that the diffusion of zinc into copper occurs via two mechanisms, i.e., grainboundary and bulk. The obtained values of the coefficient of diffusion of zinc adatoms in polycrystalline copper are equal to 1.75 × 10-15 m2/s when using direct current and 1.74 × 10-13 m2/s when using LSD.

Effect of copper on the recombination activity of extended defects in silicon

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

Feklisova, O. V., E-mail: feklisov@iptm.ru; Yakimov, E. B.

2015-06-15

The effect of copper atoms introduced by high-temperature diffusion on the recombination properties of dislocations and dislocation trails in p-type single-crystal silicon is studied by the electron-beam-induced current technique. It is shown that, in contrast to dislocations, dislocation trails exhibit an increase in recombination activity after the introduction of copper. Bright contrast appearance in the vicinity of dislocation trails is detected after the diffusion of copper and quenching of the samples. The contrast depends on the defect density in these trails.

Experimental Investigation on Laser Impact Welding of Fe-Based Amorphous Alloys to Crystalline Copper

PubMed Central

Wang, Xiao; Luo, Yapeng; Huang, Tao; Liu, Huixia

2017-01-01

Recently, amorphous alloys have attracted many researchers’ attention for amorphous structures and excellent properties. However, the welding of amorphous alloys to traditional metals in the microscale is not easy to realize in the process with amorphous structures unchanged, which restrains the application in industry. In this paper, a new method of welding Fe-based amorphous alloys (GB1K101) to crystalline copper by laser impact welding (LIW) is investigated. A series of experiments was conducted under different laser energies, during which Fe-based amorphous alloys and crystalline copper were welded successfully by LIW. In addition, the microstructure and mechanical properties of welding joints were observed and measured, respectively. The results showed that the surface wave and springback were observed on the flyer plate after LIW. The welding interface was straight or wavy due to different plastic deformation under different laser energies. The welding interface was directly bonded tightly without visible defects. No visible element diffusion and intermetallic phases were found in the welding interface. The Fe-based amorphous alloys retained amorphous structures after LIW under the laser energy of 835 mJ. The nanoindentation hardness across the welding interface showed an increase on both sides of the welding interface. The results of the lap shearing test showed that the fracture position was on the side of copper coil. PMID:28772886

Experimental Investigation on Laser Impact Welding of Fe-Based Amorphous Alloys to Crystalline Copper.

PubMed

Wang, Xiao; Luo, Yapeng; Huang, Tao; Liu, Huixia

2017-05-12

Recently, amorphous alloys have attracted many researchers' attention for amorphous structures and excellent properties. However, the welding of amorphous alloys to traditional metals in the microscale is not easy to realize in the process with amorphous structures unchanged, which restrains the application in industry. In this paper, a new method of welding Fe-based amorphous alloys (GB1K101) to crystalline copper by laser impact welding (LIW) is investigated. A series of experiments was conducted under different laser energies, during which Fe-based amorphous alloys and crystalline copper were welded successfully by LIW. In addition, the microstructure and mechanical properties of welding joints were observed and measured, respectively. The results showed that the surface wave and springback were observed on the flyer plate after LIW. The welding interface was straight or wavy due to different plastic deformation under different laser energies. The welding interface was directly bonded tightly without visible defects. No visible element diffusion and intermetallic phases were found in the welding interface. The Fe-based amorphous alloys retained amorphous structures after LIW under the laser energy of 835 mJ. The nanoindentation hardness across the welding interface showed an increase on both sides of the welding interface. The results of the lap shearing test showed that the fracture position was on the side of copper coil.

Installation Restoration Program. Remedial Investigation Report: Forbes Field Air National Guard Base, Topeka, Kansas

DTIC Science & Technology

1989-10-01

of toluene in the gastrointestinal tract occurs less readily. Toluene is distributed in the highest concentrations to adipose tissue followed by bone...were desorbed using a thermal desorption unit. Samples were injected by a desorber into a capillary column which was followed by quantification with...0.002 beryllium 0.1 0.001 cadmium 0.5 0.005 chromium 1 0.01 copper 1 0.01 lead 3 0.002 mercury 0.02 0.001 nickel 2 0.02 selenium 0.2 0.002 silver 0.5

Environmental Assessment of the Muscatatuck Urban Training Center near Butlerville, Indiana, October and November 2005

USGS Publications Warehouse

Risch, Martin R.; Ulberg, Amanda L.; Robinson, Bret A.

2007-01-01

Concentrations of constituents detected in these samples were compared with regulatory standards (the Indiana Surface-Water-Quality Standards and Indiana Ground-Water-Quality Standards) and guidance criteria from the Indiana Department of Environmental Management's Risk Integrated System of Closures for contaminated soil and ground water. Standards or criteria were exceeded by 17 constituent concentrations in 11 environmental samples from 5 of the 7 geographic study areas. Standards or criteria were exceeded for 10 constituents: ammonia, arsenic, benzo(a)pyrene, beryllium, chloride, chloroform, copper, lead, sulfate, and zinc.

Industrial Implementation of Environmentally Friendly Nanometal Electroplating Process for Chromium and Copper Beryllium Replacement using Low Cost Pulse Current Power Supplies

DTIC Science & Technology

2014-09-10

Cr-Mo, and stainless steel have to some extent found acceptance in various military and commercial CuBe-replacement roles. 1.1.2 Proposed...including low and high strength steels , stainless steel , Inconel and nickel. Figure 4-8 Activation line used to prepare components for nCoP plating...size up to a maximum thickness of 0.012”, can be produced in the tank by electroforming onto a flat stainless steel mandrel and subsequently

Doping of germanium and silicon crystals with non-hydrogenic acceptors for far infrared lasers

DOEpatents

Haller, Eugene E.; Brundermann, Erik

2000-01-01

A method for doping semiconductors used for far infrared lasers with non-hydrogenic acceptors having binding energies larger than the energy of the laser photons. Doping of germanium or silicon crystals with beryllium, zinc or copper. A far infrared laser comprising germanium crystals doped with double or triple acceptor dopants permitting the doped laser to be tuned continuously from 1 to 4 terahertz and to operate in continuous mode. A method for operating semiconductor hole population inversion lasers with a closed cycle refrigerator.

Kinetic modeling of copper biosorption by immobilized biomass

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

Veglio, F.; Beolchini, F.; Toro, L.

1998-03-01

Biosorption of heavy metals is one of the most promising technologies involved in the removal of toxic metals from industrial waste streams and natural waters. The kinetic modeling of copper biosorption by Arthrobacter sp. immobilized in a hydroxyethyl methacrylate-based matrix is reported in this work. The resin-biomass complex (RBC) has been used for copper biosorption in different conditions according to a factorial experiment. Factors investigated were cross-linker (trimethylolpropane trimethacrylate) concentration, biomass concentration in the solid, and particles` granulometry. A maximum copper specific uptake of abut 7 mg of Cu/g of biomass (dry weight) has been observed, in the case ofmore » a RBC with the following characteristics: 2% (w/w) cross-linker concentration, 8% (w/w) biomass concentration, and 425--750 {micro}m granulometry. The shrinking core model has been used for the fitting of experimental data. A good fit has been found in the case of controlling intraparticle diffusion in all experimental trials. The copper diffusion coefficient in RBC has been estimated from the slope of the regression lines. Values obtained for the diffusion coefficients do not differ from one another with respect to the estimated standard error. An average apparent copper diffusion coefficient of about 3 {times} 10{sup {minus}6} cm{sup 2}/s has been found.« less

Kinetics of copper ion absorption by cross-linked calcium polyacrylate membranes

NASA Technical Reports Server (NTRS)

Philipp, W. H.; May, C. E.

1983-01-01

The absorption of copper ions from aqueous copper acetate solutions by cross-linked calcium acrylate membranes was found to obey parabolic kinetics similar to that found for oxidation of metals that form protective oxide layers. For pure calcium polyacrylate membranes the rate constant was essentially independent of copper acetate concentration and film thickness. For a cross-linked copolymer film of polyvinyl alcohol and calcium polyacrylate, the rate constant was much greater and dependent on the concentration of copper acetate. The proposed mechanism in each case involves the formation of a copper polyacrylate phase on the surface of the membrane. The diffusion of the copper ion through this phase appears to be the rate controlling step for the copolymer film. The diffusion of the calcium ion is apparently the rate controlling step for the calcium polyacrylate. At low pH, the copper polyacrylate phase consists of the normal copper salt; at higher pH, the phase appears to be the basic copper salt.

Cosmic X-ray physics

NASA Technical Reports Server (NTRS)

Mccammon, D.; Cox, D. P.; Kraushaar, W. L.; Sanders, W. T.

1986-01-01

The analysis of the beryllium-filtered data from Flight 17.020 was completed. The data base provided by the Wisconsin diffuse X-ray sky survey is being analyzed by correlating the B and C band emission with individual velocity components of neutral hydrogen. Work on a solid state detector to be used in high resolution spectroscopy of diffuse or extend X-ray sources is continuing. A series of 21 cm observations was completed. A paper on the effects of process parameter variation on the reflectivity of sputter-deposited tungsten-carvon multilayers was published.

Structure and Microhardness of Cu-Ta Joints Produced by Explosive Welding

PubMed Central

Maliutina, Iu. N.; Mali, V. I.; Bataev, I. A.; Bataev, A. A.; Esikov, M. A.; Smirnov, A. I.; Skorokhod, K. A.

2013-01-01

The structure and microhardness of Cu-Ta joints produced by explosive welding were studied. It was found that, during explosive welding, an intermediate layer 20⋯40 μm thick with a finely dispersed heterophase structure, formed between the welded copper and tantalum plates. The structure of the layer was studied by scanning and transmission electron microscopy. Microvolumes with tantalum particles distributed in a copper matrix and microvolumes of copper particles in a tantalum matrix were detected. The tantalum particles in copper have a size of 5⋯500 nm, with a predominance of 5⋯50 nm particles. A mechanism for the formation of the finely dispersed heterophase structure in explosive welding is proposed. The microhardness of interlayers with the heterophase structure reaches 280 HV, which far exceeds the microhardness of copper (~130 HV) and tantalum (~160 HV). Many twins of deformation origin were found in the structure of the copper plate. The effect of heating temperature in the range from 100 to 900°C on the microhardness of copper, tantalum, and the Cu-Ta welded joint was studied. Upon heating to 900°C, the microhardness of the intermediate layer decreases from 280 to 150 HV. The reduction in the strength properties of the weld material is mainly due to structural transformations in copper. PMID:24453818

A New Vacuum Brazing Route for Niobium-316L Stainless Steel Transition Joints for Superconducting RF Cavities

NASA Astrophysics Data System (ADS)

Kumar, Abhay; Ganesh, P.; Kaul, R.; Bhatnagar, V. K.; Yedle, K.; Ram Sankar, P.; Sindal, B. K.; Kumar, K. V. A. N. P. S.; Singh, M. K.; Rai, S. K.; Bose, A.; Veerbhadraiah, T.; Ramteke, S.; Sridhar, R.; Mundra, G.; Joshi, S. C.; Kukreja, L. M.

2015-02-01

The paper describes a new approach for vacuum brazing of niobium-316L stainless steel transition joints for application in superconducting radiofrequency cavities. The study exploited good wettability of titanium-activated silver-base brazing alloy (CuSil-ABA®), along with nickel as a diffusion barrier, to suppress brittle Fe-Nb intermetallic formation, which is well reported during the established vacuum brazing practice using pure copper filler. The brazed specimens displayed no brittle intermetallic layers on any of its interfaces, but instead carried well-distributed intermetallic particles in the ductile matrix. The transition joints displayed room temperature tensile and shear strengths of 122-143 MPa and 80-113 MPa, respectively. The joints not only exhibited required hermeticity (helium leak rate <1.1 × 10-10 mbar l/s) for service in ultra-high vacuum but also withstood twelve hour degassing heat treatment at 873 K (suppresses Q-disease in niobium cavities), without any noticeable degradation in the microstructure and the hermeticity. The joints retained their leak tightness even after undergoing ten thermal cycles between the room temperature and the liquid nitrogen temperature, thereby establishing their ability to withstand service-induced low cycle fatigue conditions. The study proposes a new lower temperature brazing route to form niobium-316L stainless steel transition joints, with improved microstructural characteristics and acceptable hermeticity and mechanical properties.

Microstructure evolution in dissimilar AA6060/copper friction stir welded joints

NASA Astrophysics Data System (ADS)

Kalashnikova, T. A.; Shvedov, M. A.; Vasilyev, P. A.

2017-12-01

Friction stir welding process has been applied for making a dissimilar copper/aluminum alloy joint. The grain microstructure and mechanical properties of the obtained joint were studied. The structure of the cross-section of the FSW compound was analyzed. The microstructural evolution of the joint was examined using optical microscopy. The mechanical properties of the intermetallic particles were evaluated by measuring the microhardness according to the Vickers method. The microhardness of the intermetallic particles was by a factor of 4 lower than that of the particles obtained by fusion welding. The results of the investigations enable using friction stir welding for making dissimilar joints.

Thermal and Surface Evaluation on The Process of Forming a Cu2O/CuO Semiconductor Photocatalyst on a Thin Copper Plate

NASA Astrophysics Data System (ADS)

Zainul, R.; Oktavia, B.; Dewata, I.; Efendi, J.

2018-04-01

This research aims to investigate the process of forming a multi-scale copper oxide semiconductor (CuO/Cu2O) through a process of calcining a copper plate. The changes that occur during the formation of the oxide are thermally and surface evaluated. Evaluation using Differential Thermal Analysis (DTA) obtained by surface change of copper plate happened at temperature 380°C. Calcination of oxide formation was carried out at temperature 380°C for 1 hour. Surface evaluation process by using Scanning Electron Microscope (SEM) surface and cross-section, to determine diffusion of oxide formation on copper plate. The material composition is monitored by XRF and XRD to explain the process of structural and physical changes of the copper oxide plate formed during the heating process. The thickness of Cu plates used is 200-250 μm. SEM analysis results, the oxygen atom interruption region is in the range of 20-30 μm, and diffuses deeper during thermal oxidation process. The maximum diffusion depth of oxygen atoms reaches 129 μm.

Brazing Inconel 625 Using the Copper Foil

NASA Astrophysics Data System (ADS)

Chen, Wen-Shiang; Wang, Cheng-Yen; Shiue, Ren-Kae

2013-12-01

Brazing Inconel 625 (IN-625) using the copper foil has been investigated in this research. The brazed joint is composed of nanosized CrNi3 precipitates and Cr/Mo/Nb/Ni quaternary compound in the Cu/Ni-rich matrix. The copper filler 50 μm in thickness is enough for the joint filling. However, the application of Cu foil 100 μm in thickness has little effect on the shear strength of the brazed joint. The specimen brazed at 1433 K (1160 °C) for 1800 seconds demonstrates the best shear strength of 470 MPa, and its fractograph is dominated by ductile dimple fracture with sliding marks. Decreasing the brazing temperature slightly decreases the shear strength of the brazed joint due to the presence of a few isolated solidification shrinkage voids smaller than 15 μm. Increasing the brazing temperature, especially for the specimen brazed at 1473 K (1200 °C), significantly deteriorates the shear strength of the joint below 260 MPa because of coalescence of isothermal solidification shrinkage voids in the joint. The Cu foil demonstrates potential in brazing IN-625 for industrial application.

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

Electromigration induced high fraction of compound formation in SnAgCu flip chip solder joints with copper column

NASA Astrophysics Data System (ADS)

Xu, Luhua; Han, Jung-Kyu; Liang, Jarrett Jun; Tu, K. N.; Lai, Yi-Shao

2008-06-01

To overcome the effect of current crowding on electromigration-induced pancake-type void formation in flip chip solder joints, two types of Cu column in 90μm flip chip SnAgCu solder joints have been studied. They were (1) the solder contacts the Cu column at bottom and side walls and (2) the solder wets only the bottom surface of the copper column. With a current density of 1.6×104A/cm2 at 135°C, no failure was detected after 1290h. However, the resistance increased by about 10% due to the formation of a large fraction of intermetallic compounds. We found that electromigration has accelerated the consumption rate of copper column and converted almost the entire solder joint into intermetallic compound. Mechanically, drop impact test indicates a brittle fracture failure in the intermetallic. The electromigration critical product for the intermetallic is discussed.

Data on surface-water, streambed-interstitial water, and bed-sediment quality for selected locations in the small arms impact area of central Fort Gordon, Georgia, September 4-6, 2001

USGS Publications Warehouse

Priest, Sheryln; Stamey, Timothy C.; Lawrence, Stephen J.

2002-01-01

In September 2001, the U.S. Geological Survey, in cooperation with the Environmental and Natural Resources Management Office of the U.S. Army Signal Center and Fort Gordon (U.S. Department of the Army), conducted a chemical assessment of surface water, streambed-interstitial water, and bed sediments within the small arms impact area of Fort Gordon Military Installation. The study was conducted in support of the development of an Integrated Natural Resources Management Plan (INRMP) for Fort Gordon, Georgia. An effective INRMP ensures that natural resources conservation measures and U.S. Army activities on the military base are integrated and consistent with Federal requirements to manage military installations on an ecosystem basis. Filtered water samples were collected from five sites along South Prong Creek and three sites along Marcum Branch Creek for chemical analyses of major ions, nutrients, and selected trace elements. On-site measurements of pH, temperature, specific conductance, and dissolved oxygen were made at the eight sites. Filtered water collected showed varying concentrations in both surface- and streambed-interstitial water. Bed-sediment samples collected from South Prong Creek contain elevated levels of arsenic, barium, beryllium, cadmium, chromium, cobalt, copper, iron, lead, manganese, nickel, selenium, vanadium, and total organic carbon relative to previous concentrations (McConnell and others, 2000). Bed-sediment samples collected from Marcum Branch Creek contain elevated levels of beryllium, copper, lead, manganese, mercury, selenium, and total organic carbon relative to previous concentrations (McConnell and others, 2000).

Enhanced thermal diffusivity of copperbased composites using copper-RGO sheets

NASA Astrophysics Data System (ADS)

Kim, Sangwoo; Kwon, Hyouk-Chon; Lee, Dohyung; Lee, Hyo-Soo

2017-11-01

The synthesis of copper-reduced graphene oxide (RGO) sheets was investigated in order to control the agglutination of interfaces and develop a manufacturing process for copper-based composite materials based on spark plasma sintering. To this end, copper-GO (graphene oxide) composites were synthesized using a hydrothermal method, while the copper-reduced graphene oxide composites were made by hydrogen reduction. Graphene oxide-copper oxide was hydrothermally synthesized at 80 °C for 5 h, and then annealed at 800 °C for 5 h in argon and hydrazine rate 9:1 to obtain copper-RGO flakes. The morphology and structure of these copper-RGO sheets were characterized using scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and Raman spectroscopy. After vibratory mixing of the synthesized copper-RGO composites (0-2 wt%) with copper powder, they were sintered at 600 °C for 5 min under100 MPa of pressure by spark plasma sintering process. The thermal diffusivity of the resulting sintered composite was characterized by the laser flash method at 150 °C.

Process for the Production of Star Tracklng [Tracking] Reticles

NASA Technical Reports Server (NTRS)

Smith, Wade O. (Inventor); Toft, Albert R. (Inventor)

1972-01-01

A method for the production of reticles, particularly those for use in outer space, wherein the product is a quartz base coated with highly adherent layers of chromium, chromium-silver, and silver vacuum deposited through a mask, and then coated with an electrodeposit of copper from a copper sulfate solution followed by an electrodeposit of black chromium. The masks are produced by coating a beryllium-copper alloy substrate with a positive working photoresist, developing the photoresist according to a pattern to leave a positive mask, plating uncoated areas with gold, removing the photoresist, coating the substrate with a negative working photoresist, developing the negative working photoresist to expose the base metal of the pattern, and chemically etching the unplated side of the pattern to produce the mask. The mask produced is then used in the vacuum deposition of: (1) chromium metal on the surface of a quartz base to obtain a highly adherent quartz-chromium interface; (2) silver on the chromium deposit, during the final stage of chromium deposit, to produce a silver chromium alloy layer; and (3) silver onto the surface of the alloy layer. The coated quartz base is then coated by electroplating utilizing an acid copper deposit followed by a black chromium electrodeposit to produce the product of the present invention.

Ultrasonic-assisted soldering of Cu/Ti joints

NASA Astrophysics Data System (ADS)

Cui, Wei; Wang, Chunyu; Li, Yuhang; Zhong, Tongtong; Yang, Jianguo; Bao, Yefeng

2018-03-01

Cu/Ti joints are expected to be used in various applications, while reliable joining method is still to be developed. It is commonly not possible to solder Ti alloys using Sn-based solder alloys because of their poor wettability. In this study, Sn-Ag-Cu soldering filler metal was used to joining TC4 titanium alloy and pure copper using ultrasonic-assisted soldering. The influence of different temperature and different ultrasonic time on the welded joint is studied and explored. Microstructure of the joints was investigated. Shear strength of the joints reached the maximum value, i.e. 38.2MPa. Relationship between the sonication parameters and the microstructure and strength of the joints was discussed. Thus, it is verified that dissimilar metal brazing of TC4 and copper is suitable for low temperature soldering.

The Mechanism of Ultrasonic Vibration on Grain Refining and Degassing in GTA Spot Welding of Copper Joints.

PubMed

Al-Ezzi, Salih; Quan, Gaofeng; Elrayah, Adil

2018-05-07

This paper examines the effect of ultrasonic vibration (USV) on grain size and interrupted porosity in Gas Tungsten Arc (GTA) spot-welded copper. Grain size was refined by perpendicularly attaching a transducer to the welded sheet and applying USV to the weld pool for a short time (0, 2, 4, and 6 s) in addition improvements to the degassing process. Results illustrate a significant reduction of grain size (57%). Notably, USV provided interaction between reformations (fragmentation) and provided nucleation points (detaching particles from the fusion line) for grains in the nugget zone and the elimination of porosity in the nugget zone. The GTA spot welding process, in conjunction with USV, demonstrated an improvement in the corrosion potential for a copper spot-welded joint in comparison to the joint welded without assistance of USV. Finally, welding of copper by GTA spot welding in conjunction with ultrasound for 2 s presented significant mechanical properties.

The Mechanism of Ultrasonic Vibration on Grain Refining and Degassing in GTA Spot Welding of Copper Joints

PubMed Central

Quan, Gaofeng

2018-01-01

This paper examines the effect of ultrasonic vibration (USV) on grain size and interrupted porosity in Gas Tungsten Arc (GTA) spot-welded copper. Grain size was refined by perpendicularly attaching a transducer to the welded sheet and applying USV to the weld pool for a short time (0, 2, 4, and 6 s) in addition improvements to the degassing process. Results illustrate a significant reduction of grain size (57%). Notably, USV provided interaction between reformations (fragmentation) and provided nucleation points (detaching particles from the fusion line) for grains in the nugget zone and the elimination of porosity in the nugget zone. The GTA spot welding process, in conjunction with USV, demonstrated an improvement in the corrosion potential for a copper spot-welded joint in comparison to the joint welded without assistance of USV. Finally, welding of copper by GTA spot welding in conjunction with ultrasound for 2 s presented significant mechanical properties. PMID:29735894

Water-quality assessment of part of the Upper Mississippi River Basin, Minnesota and Wisconsin: Trace elements in streambed sediment and fish livers, 1995-96

USGS Publications Warehouse

Kroening, Sharon E.; Fallon, James D.; Lee, Kathy E.

2000-01-01

In fish livers, all of the trace elements analyzed were detected except antimony, beryllium, cobalt, and uranium. Trace element concentrations in fish livers generally did not show any pronounced patterns. Ranges for concentrations of arsenic, cadmium, chromium, copper, lead, mercury, nickel, selenium, and zinc were similar to those measured in 20 other NAWQA studies across the United States. Cadmium concentrations in fish livers were moderately correlated to fish length and weight. There were no relations between trace element concentrations in fish livers and streambed sediment.

A Study of Multiplicities in Hadronic Interactions (in Spanish)

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

Estrada Tristan, Nora Patricia; /San Luis Potosi U.

Using data from the SELEX (Fermilab E781) experiment obtained with a minimum-bias trigger, we study multiplicity and angular distributions of secondary particles produced in interactions in the experimental targets. We observe interactions of {Sigma}{sup -}, proton, {pi}{sup -}, and {pi}{sup +}, at beam momenta between 250 GeV/c and 650 GeV/c, in copper, polyethylene, graphite, and beryllium targets. We show that the multiplicity and angular distributions for meson and baryon beams at the same momentum are identical. We also show that the mean multiplicity increases with beam momentum, and presents only small variations with the target material.

Load regulating expansion fixture

DOEpatents

Wagner, Lawrence M.; Strum, Michael J.

1998-01-01

A free standing self contained device for bonding ultra thin metallic films, such as 0.001 inch beryllium foils. The device will regulate to a predetermined load for solid state bonding when heated to a bonding temperature. The device includes a load regulating feature, whereby the expansion stresses generated for bonding are regulated and self adjusting. The load regulator comprises a pair of friction isolators with a plurality of annealed copper members located therebetween. The device, with the load regulator, will adjust to and maintain a stress level needed to successfully and economically complete a leak tight bond without damaging thin foils or other delicate components.

The design and evaluation of superconducting connectors

NASA Technical Reports Server (NTRS)

Payne, J. E.

1982-01-01

The development of a superconducting connector for superconducting circuits on space flights is described. It is proposed that such connectors be used between the superconducting readout loop and the SQUID magnetometer in the Gravity Probe B experiment. Two types of connectors were developed. One type employs gold plated niobium wires making pressure connections to gold plated niobium pads. Lead-plated beryllium-copper spring contacts can replace the niobium wires. The other type is a rigid solder or weld connection between the niobium wires and the niobium pads. A description of the methods used to produce these connectors is given and their performance analyzed.

Handbook of Isotopes in the Cosmos

NASA Astrophysics Data System (ADS)

Clayton, Donald

2007-08-01

List of illustrations; Preface; Introduction; 1. Hydrogen (H); 2. Helium (He); 3. Lithium (Li); 4. Beryllium (Be); 5. Boron (B); 6. Carbon (C); 7. Nitrogen (N); 8. Oxygen (O); 9. Fluorine (F); 10. Neon (Ne); 11. Sodium (Na); 12. Magnesium (Mg); 13. Aluminium (Al); 14. Silicon (Si); 15. Phosphorous (P); 16. Sulphur (S); 17. Chlorine (Cl); 18. Argon (Ar); 19. Potassium (K); 20. Calcium (Ca); 21. Scandium (Sc); 22. Titanium (Ti); 23. Vanadium (V); 24. Chromium (Cr); 25. Manganese (Mn); 26. Iron (Fe); 27. Cobalt (Co); 28. Nickel (Ni); 29. Copper (Cu); 30. Zinc (Zn); 31. Gallium (Ga); Glossary.

Handbook of Isotopes in the Cosmos

NASA Astrophysics Data System (ADS)

Clayton, Donald

2003-09-01

List of illustrations; Preface; Introduction; 1. Hydrogen (H); 2. Helium (He); 3. Lithium (Li); 4. Beryllium (Be); 5. Boron (B); 6. Carbon (C); 7. Nitrogen (N); 8. Oxygen (O); 9. Fluorine (F); 10. Neon (Ne); 11. Sodium (Na); 12. Magnesium (Mg); 13. Aluminium (Al); 14. Silicon (Si); 15. Phosphorous (P); 16. Sulphur (S); 17. Chlorine (Cl); 18. Argon (Ar); 19. Potassium (K); 20. Calcium (Ca); 21. Scandium (Sc); 22. Titanium (Ti); 23. Vanadium (V); 24. Chromium (Cr); 25. Manganese (Mn); 26. Iron (Fe); 27. Cobalt (Co); 28. Nickel (Ni); 29. Copper (Cu); 30. Zinc (Zn); 31. Gallium (Ga); Glossary.

A combined kick-out and dissociative diffusion mechanism of grown-in Be in InGaAs and InGaAsP. A new finite difference-Bairstow method for solution of the diffusion equations

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

Koumetz, Serge D., E-mail: Serge.Koumetz@univ-rouen.fr; Martin, Patrick; Murray, Hugues

Experimental results on the diffusion of grown-in beryllium (Be) in indium gallium arsenide (In{sub 0.53}Ga{sub 0.47}As) and indium gallium arsenide phosphide (In{sub 0.73}Ga{sub 0.27}As{sub 0.58}P{sub 0.42}) gas source molecular beam epitaxy alloys lattice-matched to indium phosphide (InP) can be successfully explained in terms of a combined kick-out and dissociative diffusion mechanism, involving neutral Be interstitials (Be{sub i}{sup 0}), singly positively charged gallium (Ga), indium (In) self-interstitials (I{sub III}{sup +}) and singly positively charged Ga, In vacancies (V{sub III}{sup +}). A new numerical method of solution to the system of diffusion equations, based on the finite difference approximations and Bairstow's method,more » is proposed.« less

Deposition and properties of cobalt- and ruthenium-based ultra-thin films

NASA Astrophysics Data System (ADS)

Henderson, Lucas Benjamin

Future copper interconnect systems will require replacement of the materials that currently comprise both the liner layer(s) and the capping layer. Ruthenium has previously been considered as a material that could function as a single material liner, however its poor ability to prevent copper diffusion makes it incompatible with liner requirements. A recently described chemical vapor deposition route to amorphous ruthenium-phosphorus alloy films could correct this problem by eliminating the grain boundaries found in pure ruthenium films. Bias-temperature stressing of capacitor structures using 5 nm ruthenium-phosphorus film as a barrier to copper diffusion and analysis of the times-to-failure at accelerated temperature and field conditions implies that ruthenium-phosphorus performs acceptably as a diffusion barrier for temperatures above 165°C. The future problems associated with the copper capping layer are primarily due to the poor adhesion between copper and the current Si-based capping layers. Cobalt, which adheres well to copper, has been widely proposed to replace the Si-based materials, but its ability to prevent copper diffusion must be improved if it is to be successfully implemented in the interconnect. Using a dual-source chemistry of dicobaltoctacarbonyl and trimethylphosphine at temperatures from 250-350°C, amorphous cobalt-phosphorus can be deposited by chemical vapor deposition. The films contain elemental cobalt and phosphorus, plus some carbon impurity, which is incorporated in the film as both graphitic and carbidic (bonded to cobalt) carbon. When deposited on copper, the adhesion between the two materials remains strong despite the presence of phosphorus and carbon at the interface, but the selectivity for growth on copper compared to silicon dioxide is poor and must be improved prior to consideration for application in interconnect systems. A single molecule precursor containing both cobalt and phosphorus atoms, tetrakis(trimethylphosphine)cobalt(0), yields cobalt-phosphorus films without any co-reactant. However, the molecule does not contain sufficient amounts of amorphizing agents to fully eliminate grain boundaries, and the resulting film is nanocrystalline.

Investigation of the structure and properties of titanium-stainless steel permanent joints obtained by laser welding with the use of intermediate inserts and nanopowders

NASA Astrophysics Data System (ADS)

Cherepanov, A. N.; Orishich, A. M.; Pugacheva, N. B.; Shapeev, V. P.

2015-03-01

Results of an experimental study of the structure, the phase composition, and the mechanical properties of laser-welded joints of 3-mm thick titanium and 12Kh18N10T steel sheets obtained with the use of intermediate inserts and nanopowdered modifying additives are reported. It is shown that that such parameters as the speed of welding, the radiation power, and the laser-beam focal spot position all exert a substantial influence on the welding-bath process and on the seam structure formed. In terms of chemical composition, most uniform seams with the best mechanical strength are formed at a 1-m/min traverse speed of laser and 2.35-kW laser power, with the focus having been positioned at the lower surface of the sheets. Under all other conditions being identical, uplift of the focus to workpiece surface or to a higher position results in unsteady steel melting, in a decreased depth and reduced degree of the diffusion-induced mixing of elements, and in an interpolate connection formed according to the soldering mechanism in the root portion of the seam. The seam material is an over-saturated copper-based solid solution of alloying elements with homogeneously distributed intermetallic disperse particles (Ti(Fe, Cr)2 and TiCu3) contained in this alloy. Brittle fracture areas exhibiting cleavage and quasi-cleavage facets correspond to coarse Ti(Fe, Cr)2 intermetallic particles or to diffusion zones primarily occurring at the interface with the titanium alloy. The reported data and the conclusions drawn from the numerical calculations of the thermophysical processes of welding of 3-mm thick titanium and steel sheets through an intermediate copper insert are in qualitative agreement with the experimental data. The latter agreement points to adequacy of the numerical description of the melting processes of contacting materials versus welding conditions and focal-spot position in the system.

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 Drag Reducing Polymer and Suspended Solid on the Rate of Diffusion Controlled Corrosion in 90° Copper Elbow

NASA Astrophysics Data System (ADS)

Fouad, Mohamed Ahmed; Zewail, Taghreed Mohamed; Amine, Nieven Kamal Abbes

2017-06-01

Rate of diffusion controlled corrosion in 90° Copper Elbow acidified dichromate has been investigated in relation to the following parameters: effect of solution velocity in the absence and presence of drag- reducing polymer on the rate of diffusion controlled corrosion, and effect of the presence of suspended solids on the rate of diffusion controlled corrosion. It was found that the presence of drag reducing polymer inhibited the rate of mass transfer, while the presence of suspended solid increased significantly the rate of mass transfer.

Is Subsurface Oxygen Necessary for the Electrochemical Reduction of CO 2 on Copper?

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

Garza, Alejandro J.; Bell, Alexis T.; Head-Gordon, Martin

It has recently been proposed that subsurface oxygen is crucial for the adsorption and subsequent electroreduction of CO 2 on copper. Using density functional theory, we have studied the stability and diffusion of subsurface oxygen in single crystals of copper exposing (111) and (100) facets. Oxygen is at least 1.5 eV more stable on the surface than beneath it for both crystal orientations; interstitial sites are too small to accommodate oxygen. Here, the rate of atomic oxygen diffusion from one layer below a Cu(111) surface to the surface is 5 × 10 3 s –1. Oxygen can survive longer inmore » deeper layers, but it does not promote CO 2 adsorption there. Diffusion of subsurface oxygen is easier to the less-dense Cu(100) surface, even from lower layers (rate ≈ 1 × 107 s–1). Finally, once the applied voltage and dispersion forces are properly modeled, we find that subsurface oxygen is unnecessary for CO 2 adsorption on copper.« less

Is Subsurface Oxygen Necessary for the Electrochemical Reduction of CO 2 on Copper?

DOE PAGES

Garza, Alejandro J.; Bell, Alexis T.; Head-Gordon, Martin

2018-01-17

It has recently been proposed that subsurface oxygen is crucial for the adsorption and subsequent electroreduction of CO 2 on copper. Using density functional theory, we have studied the stability and diffusion of subsurface oxygen in single crystals of copper exposing (111) and (100) facets. Oxygen is at least 1.5 eV more stable on the surface than beneath it for both crystal orientations; interstitial sites are too small to accommodate oxygen. Here, the rate of atomic oxygen diffusion from one layer below a Cu(111) surface to the surface is 5 × 10 3 s –1. Oxygen can survive longer inmore » deeper layers, but it does not promote CO 2 adsorption there. Diffusion of subsurface oxygen is easier to the less-dense Cu(100) surface, even from lower layers (rate ≈ 1 × 107 s–1). Finally, once the applied voltage and dispersion forces are properly modeled, we find that subsurface oxygen is unnecessary for CO 2 adsorption on copper.« less

Preliminary study on pressure brazing and diffusion welding of Nb-1Zr to Inconel 718

NASA Technical Reports Server (NTRS)

Moore, T. J.

1990-01-01

Future space power systems may include Nb-1Zr/Inconel 718 dissimilar metal joints for operation at 1000 K for 60,000 h. The serviceability of pressure-brazed and diffusion-welded joints was investigated. Ni-based metallic glass foil filler metals were used for brazing. Ni and Fe foils were used as diffusion welding inter-layers. Joint soundness was determined by metallographic examination in the as-brazed and as-welded condition, after aging at 1000 K, and after thermal cycling. Brazed joints thermally cycled in the as-brazed condition and diffusion-welded joints were unsatisfactory because of cracking problems. Brazed joints may meet the service requirements if the joints are aged at 1000 K prior to thermal cycling.

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.

Technical Basis for PNNL Beryllium Inventory

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

Johnson, Michelle Lynn

2014-07-09

The Department of Energy (DOE) issued Title 10 of the Code of Federal Regulations Part 850, “Chronic Beryllium Disease Prevention Program” (the Beryllium Rule) in 1999 and required full compliance by no later than January 7, 2002. The Beryllium Rule requires the development of a baseline beryllium inventory of the locations of beryllium operations and other locations of potential beryllium contamination at DOE facilities. The baseline beryllium inventory is also required to identify workers exposed or potentially exposed to beryllium at those locations. Prior to DOE issuing 10 CFR 850, Pacific Northwest Nuclear Laboratory (PNNL) had documented the beryllium characterizationmore » and worker exposure potential for multiple facilities in compliance with DOE’s 1997 Notice 440.1, “Interim Chronic Beryllium Disease.” After DOE’s issuance of 10 CFR 850, PNNL developed an implementation plan to be compliant by 2002. In 2014, an internal self-assessment (ITS #E-00748) of PNNL’s Chronic Beryllium Disease Prevention Program (CBDPP) identified several deficiencies. One deficiency is that the technical basis for establishing the baseline beryllium inventory when the Beryllium Rule was implemented was either not documented or not retrievable. In addition, the beryllium inventory itself had not been adequately documented and maintained since PNNL established its own CBDPP, separate from Hanford Site’s program. This document reconstructs PNNL’s baseline beryllium inventory as it would have existed when it achieved compliance with the Beryllium Rule in 2001 and provides the technical basis for the baseline beryllium inventory.« less

Grain boundary and triple junction diffusion in nanocrystalline copper

NASA Astrophysics Data System (ADS)

Wegner, M.; Leuthold, J.; Peterlechner, M.; Song, X.; Divinski, S. V.; Wilde, G.

2014-09-01

Grain boundary and triple junction diffusion in nanocrystalline Cu samples with grain sizes, , of ˜35 and ˜44 nm produced by spark plasma sintering were investigated by the radiotracer method using the 63Ni isotope. The measured diffusivities, Deff, are comparable with those determined previously for Ni grain boundary diffusion in well-annealed, high purity, coarse grained, polycrystalline copper, substantiating the absence of a grain size effect on the kinetic properties of grain boundaries in a nanocrystalline material at grain sizes d ≥ 35 nm. Simultaneously, the analysis predicts that if triple junction diffusion of Ni in Cu is enhanced with respect to the corresponding grain boundary diffusion rate, it is still less than 500ṡDgb within the temperature interval from 420 K to 470 K.

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.

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.

Superplastic Forming of Duplex Stainless Steel for Aerospace Part

NASA Astrophysics Data System (ADS)

Lee, Ho-Sung; Yoon, Jong-Hoon; Yoo, Joon-Tae; Yi, Young-Moo

2011-08-01

In this study, the high temperature forming behavior of duplex stainless steel has been characterized and the outer shell of a combustion chamber was fabricated with pressure difference of hot gas. It consists of two parts which are the outer skin made of stainless steel to sustain the internal pressure and the inner shell made of copper alloy for regenerative cooling channels. Two outer skins partitioned to half with respect to the symmetric axis was prepared by hot gas forming process with a maximum pressure of 7 MPa following to FEM analysis. For inner layer, copper alloy was machined for cooling channels and then placed in the gas pressure welding fixture. It is shown that the optimum condition of gas pressure welding is 7 MPa at 890 °C, for one hour. EDX analysis and scanning electron microscope micrograph confirm the atomic diffusion process is observed at the interface and copper atoms diffuse into steel, while iron and chrome atoms diffuse into copper. The result shows that the manufacturing method with superplastic forming and gas pressure welding of steel and copper alloy has been successful for near net shape manufacturing of scaled combustion chamber of launch vehicle.

Separation of copper ions from iron ions using PVA-g-(acrylic acid/N-vinyl imidazole) membranes prepared by radiation-induced grafting.

PubMed

Ajji, Zaki; Ali, Ali M

2010-01-15

Acrylic acid (AAc), N-vinyl imidazole (Azol) and their binary mixtures were graft copolymerized onto poly(vinyl alcohol) membranes using gamma irradiation. The ability of the grafted membranes to separate Cu ions from Fe ions was investigated with respect to the grafting yield and the pH of the feed solution. The data showed that the diffusion of copper ions from the feed compartment to the receiver compartment depends on the grafting yield of the membranes and the pH of the feed solution. To the contrary, iron ions did not diffuse through the membranes of all grafting yields. However, a limited amount of iron ions diffused in strong acidic medium. This study shows that the prepared membranes could be considered for the separation of copper ions from iron ions. The temperature of thermal decomposition of pure PVA-g-AAc/Azol membrane, PVA-g-AAc/Azol membrane containing copper ions, and PVA-g-AAc/Azol membrane containing iron ions were determined using TGA analyzer. It was shown that the presence of Cu and Fe ions increases the decomposition temperature, and the membranes bonded with iron ions are more stable than those containing copper ions.

Electrochemical deposition of layered copper thin films based on the diffusion limited aggregation

PubMed Central

Wei, Chenhuinan; Wu, Guoxing; Yang, Sanjun; Liu, Qiming

2016-01-01

In this work layered copper films with smooth surface were successfully fabricated onto ITO substrate by electrochemical deposition (ECD) and the thickness of the films was nearly 60 nm. The resulting films were characterized by SEM, TEM, AFM, XPS, and XRD. We have investigated the effects of potential and the concentration of additives and found that 2D dendritic-like growth process leaded the formation of films. A suitable growth mechanism based on diffusion limited aggregation (DLA) mechanism for the copper films formation is presented, which are meaningful for further designing homogeneous and functional films. PMID:27734900

Development of low cost contacts to silicon solar cells

NASA Technical Reports Server (NTRS)

Tanner, D. P.

1980-01-01

The results of the second phase of the program of developing low cost contacts to silicon solar cells using copper are presented. Phase 1 yielded the development of a plated Pd-Cr-Cu contact system. This process produced cells with shunting problems when they were heated to 400 C for 5 minutes. Means of stopping the identified copper diffusion which caused the shunting were investigated. A contact heat treatment study was conducted with Pd-Ag, Ci-Ag, Pd-Cu, Cu-Cr, and Ci-Ni-Cu. Nickel is shown to be an effective diffusion barrier to copper.

Monitoring of copper nanoparticle penetration into dentin of human tooth in vitro

NASA Astrophysics Data System (ADS)

Selifonov, Alexey A.; Glukhovskoy, Evgeny G.; Skibina, Yulia S.; Zakharevich, Andrey M.; Begletsova, Nadezhda N.; Tuchin, Valery V.

2018-04-01

Study of the penetration depth of synthesized copper nanoparticles into cut samples of human dentin was conducted. The scanning electron microscopy was used to determine the elemental composition of fresh transverse cleavage of the dentin cut for determination of the copper nanoparticles penetration with an effective antiseptic effect. The morphology of the cut surface of the dentin of a human tooth was studied and the lower limit of the diffusion boundary was determined. It was found that copper nanoparticles penetrate into the dentin cut to a depth of 1.8 μm with the diffusion coefficient of 1.8×10-11 cm2/s. Despite the rather small size of the synthesized copper nanoparticles (20-80 nm), a rather small penetration depth can be explained by the high aggregation ability of copper nanoparticles, as well as the ability of a micellar solution of sodium dodecyl sulfate, in which nanoparticles were stabilized, to form conglomerates in micelles of much larger sizes.

Load regulating expansion fixture

DOEpatents

Wagner, L.M.; Strum, M.J.

1998-12-15

A free standing self contained device for bonding ultra thin metallic films, such as 0.001 inch beryllium foils is disclosed. The device will regulate to a predetermined load for solid state bonding when heated to a bonding temperature. The device includes a load regulating feature, whereby the expansion stresses generated for bonding are regulated and self adjusting. The load regulator comprises a pair of friction isolators with a plurality of annealed copper members located therebetween. The device, with the load regulator, will adjust to and maintain a stress level needed to successfully and economically complete a leak tight bond without damaging thin foils or other delicate components. 1 fig.

Kinetics and Mechanisms of Chemical and Biological Agents Release from Biopolymeric Microcapsules.

PubMed

Vinceković, Marko; Jurić, Slaven; Đermić, Edyta; Topolovec-Pintarić, Snježana

2017-11-08

Kinetics and mechanisms of copper cations and Trichoderma viride spores release from uncoated and chitosan coated alginate microcapsules were investigated. The gelation of a fixed amount of sodium alginate at different concentrations of copper ion solutions resulted in distinct kinetics and release mechanisms. The increase in copper cation concentration promoted, but the presence of the chitosan layer on the microcapsule surface and the increase in microcapsule size reduced the rate of active agent release. Fitting to simple Korsmeyer-Peppas empirical model revealed that the underlying release mechanism (Fickian diffusion or a combination of the diffusion and erosion mechanisms) depends on the copper cation concentration and presence of T. viride spores. The investigation pointed out that the proper selection of formulation variables helps in designing microcapsules with the desirable release of copper ions and T. viride for plant protection and nutrition.

Thin semi-rigid coaxial cables for cryogenics applications

NASA Astrophysics Data System (ADS)

Kushino, Akihiro; Kasai, Soichi

2013-03-01

We have developed cryogenic coaxial cables for low temperature signal readout from sensitive devices, such as transition edge sensors, superconducting tunnel junctions, and kinetic inductance detectors. In order to reduce heat penetration into cryogenic stages, low thermal conductivity metals were chosen for both center and outer electrical conductors. Various types of coaxial cables, employing stainless-steel, cupro-nickel, brass, beryllium-copper, phosphor-bronze, niobium, and niobium-titanium, were manufactured using drawing dies. Thermal and electrical properties were investigated between 1 and 8 K. Coaxial cables made of copper alloys showed thermal conductance roughly consistent with literature, meanwhile Nb coaxial cable must be affected by the drawing process and thermal conductance was lowered. Attenuation of superconducting Nb and NbTi coaxial cables were observed to be adequately small up to above 10 GHz compared to those of normal conducting coaxial cables, which are subject to the Wiedemann-Franz law. We also measured normal conducting coaxial cables with silver-plated center conductors to improve high frequency performance.

Beryllium fluoride film protects beryllium against corrosion

NASA Technical Reports Server (NTRS)

O donnell, P. M.; Odonnell, P. M.

1967-01-01

Film of beryllium fluoride protects beryllium against corrosion and stress corrosion cracking in water containing chloride ion concentrations. The film is formed by exposing the beryllium to fluorine gas at 535 degrees C or higher and makes beryllium suitable for space applications.

Beryllium Laboratory Analysis--The Regulations May Drive the Science

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

Taruru, Seuri K

Beryllium has many industry-specific applications, such as medical X-ray windows for diagnostic equipment, nuclear reactors, aerospace applications, precision instrumentation, and other consumer products for which lightness and rigidity is essential. According to the National Toxicology Program, beryllium oxide (BeO) is one of the most significant beryllium compounds in production. Although beryllium and its compounds have a wide array of beneficial uses, due to its unique properties it is not an ideal metal to be used in all situations. Exposure to beryllium is linked to beryllium sensitization and Chronic Beryllium Disease (CBD), which is incurable, debilitating, and potentially fatal. The Internationalmore » Agency for Research on Cancer classifies beryllium and beryllium compounds as “carcinogenic to humans” (Group I), and EPA classifies beryllium as a likely human carcinogen, the lung being the primary target organ. Laboratory analysis for beryllium samples has always presented a challenge to the analytical community. While most metals of interest to industrial hygienists have occupational exposure limits (OELs) in milligrams per cubic meter (mg/m 3), the beryllium OELs are in micrograms per cubic meter (μg/m3). Some regulatory agencies have recently published beryllium OELs so low that in some cases a laboratory limit of detection (LOD) in nanograms (ng) is required. For most substances, science drives the regulations, but for beryllium, regulations appear to be driving science to develop laboratory analytical methods that can adequately support the proposed OELs. (EPA has issued guidelines regarding ambient and community airborne beryllium exposure, but this article focuses on beryllium from an occupational exposure perspective.)« less

Beryllium Laboratory Analysis--The Regulations May Drive the Science

DOE PAGES

Taruru, Seuri K

2017-08-01

Beryllium has many industry-specific applications, such as medical X-ray windows for diagnostic equipment, nuclear reactors, aerospace applications, precision instrumentation, and other consumer products for which lightness and rigidity is essential. According to the National Toxicology Program, beryllium oxide (BeO) is one of the most significant beryllium compounds in production. Although beryllium and its compounds have a wide array of beneficial uses, due to its unique properties it is not an ideal metal to be used in all situations. Exposure to beryllium is linked to beryllium sensitization and Chronic Beryllium Disease (CBD), which is incurable, debilitating, and potentially fatal. The Internationalmore » Agency for Research on Cancer classifies beryllium and beryllium compounds as “carcinogenic to humans” (Group I), and EPA classifies beryllium as a likely human carcinogen, the lung being the primary target organ. Laboratory analysis for beryllium samples has always presented a challenge to the analytical community. While most metals of interest to industrial hygienists have occupational exposure limits (OELs) in milligrams per cubic meter (mg/m 3), the beryllium OELs are in micrograms per cubic meter (μg/m3). Some regulatory agencies have recently published beryllium OELs so low that in some cases a laboratory limit of detection (LOD) in nanograms (ng) is required. For most substances, science drives the regulations, but for beryllium, regulations appear to be driving science to develop laboratory analytical methods that can adequately support the proposed OELs. (EPA has issued guidelines regarding ambient and community airborne beryllium exposure, but this article focuses on beryllium from an occupational exposure perspective.)« less

Analysis of copper contamination in transformer insulating material with nanosecond- and femtosecond-laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Aparna, N.; Vasa, N. J.; Sarathi, R.

2018-06-01

This work examines the oil-impregnated pressboard insulation of high-voltage power transformers, for the determination of copper contamination. Nanosecond- and femtosecond-laser-induced breakdown spectroscopy revealed atomic copper lines and molecular copper monoxide bands due to copper sulphide diffusion. X-ray diffraction studies also indicated the presence of CuO emission. Elemental and molecular mapping compared transformer insulating material ageing in different media—air, N2, He and vacuum.

YF-12 Lockalloy ventral fin program, volume 1. [design analysis, fabrication, and manufacturing of aircraft structures using aluminum and beryllium alloys for the lockheed YF-12 aircraft

NASA Technical Reports Server (NTRS)

Duba, R. J.; Haramis, A. C.; Marks, R. F.; Payne, L.; Sessing, R. C.

1976-01-01

Results are presented of the YF-12 Lockalloy Ventral Fin Program which was carried out by Lockheed Aircraft Corporation - Advanced Development Projects for the joint NASA/USAF YF-12 Project. The primary purpose of the program was to redesign and fabricate the ventral fin of the YF-12 research airplane (to reduce flutter) using Lockalloy, and alloy of beryllium and aluminum, as a major structural material. A secondary purpose, was to make a material characterization study (thermodynamic properties, corrosion; fatigue tests, mechanical properties) of Lockalloy to validate the design of the ventral fin and expand the existing data base on this material. All significant information pertinent to the design and fabrication of the ventral fin is covered. Emphasis throughout is given to Lockalloy fabrication and machining techniques and attendant personnel safety precautions. Costs are also examined. Photographs of tested alloy specimens are shown along with the test equipment used.

Electrochemical evidences and consequences of significant differences in ions diffusion rate in polyacrylate-based ion-selective membranes.

PubMed

Woźnica, Emilia; Mieczkowski, Józef; Michalska, Agata

2011-11-21

The origin and effect of surface accumulation of primary ions within the ion-selective poly(n-butyl acrylate)-based membrane, obtained by thermal polymerization, is discussed. Using a new method, based on the relation between the shape of a potentiometric plot and preconditioning time, the diffusion of copper ions in the membrane was found to be slow (the diffusion coefficient estimated to be close to 10(-11) cm(2) s(-1)), especially when compared to ion-exchanger counter ions--sodium cations diffusion (a diffusion coefficient above 10(-9) cm(2) s(-1)). The higher mobility of sodium ions than those of the copper-ionophore complex results in exposed ion-exchanger role leading to undesirably exposed sensitivity to sodium or potassium ions.

Process Of Bonding Copper And Tungsten

DOEpatents

Slattery, Kevin T.; Driemeyer, Daniel E.; Davis, John W.

2000-07-18

Process for bonding a copper substrate to a tungsten substrate by providing a thin metallic adhesion promoting film bonded to a tungsten substrate and a functionally graded material (FGM) interlayer bonding the thin metallic adhesion promoting film to the copper substrate. The FGM interlayer is formed by sintering a stack of individual copper and tungsten powder blend layers having progressively higher copper content/tungsten content, by volume, ratio values in successive powder blend layers in a lineal direction extending from the tungsten substrate towards the copper substrate. The resulting copper to tungsten joint well accommodates the difference in the coefficient of thermal expansion of the materials.

Study on Joint Interface and Mechanical Properties of Cu/Pb-Sn/Cu Lap Joint Produced by Friction Stir Soldering Process

NASA Astrophysics Data System (ADS)

Sarkari Khorrami, Mahmoud; Kokabi, Amir Hossein; Movahedi, Mojtaba

2015-05-01

In this work, friction stir soldering (FSS) as a new approach for fabrication of copper/copper lap joints was introduced. This process is principally based on the friction stir processing (FSP) that can be performed using FSP tools with and without pin on the top sheet. In the present study, Pb-Sn foil was used as a solder which would be melted and then extruded in the area between the copper sheets during FSS process. This process was carried out using tools with and without pin at various rotation speeds of 1200, 1400, and 1600 rpm and traverse speed of 32 mm/min. Also, the same joint was fabricated using furnace soldering to compare the mechanical properties obtained with FSS and furnace soldering processes. It was observed that FSS possesses some advantages over the conventional furnace soldering process including the formation of more bond area at the interface corresponding to the higher fracture load of FSS joints compared with furnace soldering one. Moreover, it was concluded that the thickness of intermetallic compounds (IMCs) and the formation of voids at the joint interface were the predominant factor determining the mechanical properties of the FSS joints produced by FSS tool with and without pin, respectively. The microstructural examinations revealed that Cu-Sn IMCs of Cu3Sn and Cu6Sn5 were formed at the joint interface. It was observed that the FSS joint produced by tool with pin experienced the more peak temperature in comparison with that produced by pin-free tool. This may lead to the formation of thicker IMCs at the interface. Of course, the thickness of IMCs can be controlled by choosing proper FSS parameters, especially the rotation speed of the tool.

Laser Welding Dissimilar Reflective Alloys

NASA Technical Reports Server (NTRS)

Mccay, M. H.; Gopinathan, S.; Kahlen, F.; Speigel, L.

1993-01-01

This project, jointly sponsored by Rocketdyne and CSTAR, involves the development of laser joining of materials which have heretofore been impractical to bond. Of particular interest are joints between stainless steel and copper and also aluminum 6061 to aluminum 2219. CSTAR has a unique opportunity in this area since both the process and development and diagnostics are of interest to industry. Initial results using the pulse tailored laser welding technique developed in CLA for joining crack sensitive materials have proven promising for the aluminum joints based upon metallurgical and electronic microprobe analysis. A declaration of success requires additional mechanical testing. A CW technique has been applied to the stainless-copper joining with some preliminary success. These joints are of significant interest for aeronautics and rocket propulsion applications and the project is expected to continue.

Laser welding dissimilar reflective alloys

NASA Astrophysics Data System (ADS)

McCay, M. H.; Gopinathan, S.; Kahlen, F.; Speigel, L.

1993-01-01

This project, jointly sponsored by Rocketdyne and CSTAR, involves the development of laser joining of materials which have heretofore been impractical to bond. Of particular interest are joints between stainless steel and copper and also aluminum 6061 to aluminum 2219. CSTAR has a unique opportunity in this area since both the process and development and diagnostics are of interest to industry. Initial results using the pulse tailored laser welding technique developed in CLA for joining crack sensitive materials have proven promising for the aluminum joints based upon metallurgical and electronic microprobe analysis. A declaration of success requires additional mechanical testing. A CW technique has been applied to the stainless-copper joining with some preliminary success. These joints are of significant interest for aeronautics and rocket propulsion applications and the project is expected to continue.

Risks of beryllium disease related to work processes at a metal, alloy, and oxide production plant.

PubMed

Kreiss, K; Mroz, M M; Zhen, B; Wiedemann, H; Barna, B

1997-08-01

To describe relative hazards in sectors of the beryllium industry, risk factors of beryllium disease and sensitisation related to work process were sought in a beryllium manufacturing plant producing pure metal, oxide, alloys, and ceramics. All 646 active employees were interviewed; beryllium sensitisation was ascertained with the beryllium lymphocyte proliferation blood test on 627 employees; clinical evaluation and bronchoscopy were offered to people with abnormal test results; and industrial hygiene measurements related to work processes taken in 1984-93 were reviewed. 59 employees (9.4%) had abnormal blood tests, 47 of whom underwent bronchoscopy. 24 new cases of beryllium disease were identified, resulting in a beryllium disease prevalence of 4.6%, including five known cases (29/632). Employees who had worked in ceramics had the highest prevalence of beryllium disease (9.0%). Employees in the pebble plant (producing beryllium metal) who had been employed after 1983 also had increased risk, with a prevalence of beryllium disease of 6.4%, compared with 1.3% of other workers hired in the same period, and a prevalence of abnormal blood tests of 19.2%. Logistic regression modelling confirmed these two risk factors for beryllium disease related to work processes and the dependence on time of the risk at the pebble plant. The pebble plant was not associated with the highest gravimetric industrial hygiene measurements available since 1984. Further characterisation of exposures in beryllium metal production may be important to understanding how beryllium exposures confer high contemporary risk of beryllium disease.

Attaching Copper Wires to Magnetic-Reed-Switch Leads

NASA Technical Reports Server (NTRS)

Kamila, Rudolf

1987-01-01

Bonding method reliably joins copper wires to short iron-alloy leads from glass-encased dry magnetic-reed switch without disturbing integrity of glass-to-metal seal. Joint resistant to high temperatures and has low electrical resistance.

Defense programs beryllium good practice guide

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

Herr, M.

1997-07-01

Within the DOE, it has recently become apparent that some contractor employees who have worked (or are currently working) with and around beryllium have developed chronic beryllium disease (CBD), an occupational granulomatous lung disorder. Respiratory exposure to aerosolized beryllium, in susceptible individuals, causes an immunological reaction that can result in granulomatous scarring of the lung parenchyma, shortness of breath, cough, fatigue, weight loss, and, ultimately, respiratory failure. Beryllium disease was originally identified in the 1940s, largely in the fluorescent light industry. In 1950, the Atomic Energy Commission (AEC) introduced strict exposure standards that generally curtailed both the acute and chronicmore » forms of the disease. Beginning in 1984, with the identification of a CBD case in a DOE contractor worker, there was increased scrutiny of both industrial hygiene practices and individuals in this workforce. To date, over 100 additional cases of beryllium-specific sensitization and/or CBD have been identified. Thus, a disease previously thought to be largely eliminated by the adoption of permissible exposure standards 45 years ago is still a health risk in certain workforces. This good practice guide forms the basis of an acceptable program for controlling workplace exposure to beryllium. It provides (1) Guidance for minimizing worker exposure to beryllium in Defense Programs facilities during all phases of beryllium-related work, including the decontamination and decommissioning (D&D) of facilities. (2) Recommended controls to be applied to the handling of metallic beryllium and beryllium alloys, beryllium oxide, and other beryllium compounds. (3) Recommendations for medical monitoring and surveillance of workers exposed (or potentially exposed) to beryllium, based on the best current understanding of beryllium disease and medical diagnostic tests available. (4) Site-specific safety procedures for all processes of beryllium that is likely to generate dusts, mists, fumes, or small particulates. A beryllium exposure control program should minimize airborne concentrations, the potential for and spread of contamination, the number of times individuals are exposed to beryllium, and the number of employees who may be potentially exposed.« less

A Novel Process for Joining Ti Alloy and Al Alloy using Two-Stage Sintering Powder Metallurgy

NASA Astrophysics Data System (ADS)

Long, Luping; Liu, Wensheng; Ma, Yunzhu; Wu, Lei; Liu, Chao

2018-04-01

The major challenges for conventional diffusion bonding of joining Ti alloy and Al alloy are the undesirable interfacial reaction, low matrixes and joint strength. To avoid the problem in diffusion bonding, a novel two-stage sintering powder metallurgy process is developed. In the present work, the interface characterization and joint performance of the bonds obtained by powder metallurgy bonding are investigated and are compared with the diffusion bonded Ti/Al joints obtained with the same and the optimized process parameters. The results show that no intermetallic compound is visible in the Ti/Al joint obtained by powder metallurgy bonding, while a new layer formed at the joint diffusion bonded with the same parameters. The maximum tensile strength of joint obtained by diffusion bonding is 58 MPa, while a higher tensile strength reaching 111 MPa for a bond made by powder metallurgy bonding. Brittle fractures occur at all the bonds. It is shown that the powder metallurgy bonding of Ti/Al is better than diffusion bonding. The results of this study should benefit the bonding quality.

A new active solder for joining electronic components

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

SMITH,RONALD W.; VIANCO,PAUL T.; HERNANDEZ,CYNTHIA L.

Electronic components and micro-sensors utilize ceramic substrates, copper and aluminum interconnect and silicon. The joining of these combinations require pre-metallization such that solders with fluxes can wet such combinations of metals and ceramics. The paper will present a new solder alloy that can bond metals, ceramics and composites. The alloy directly wets and bonds in air without the use flux or premetallized layers. The paper will present typical processing steps and joint microstructures in copper, aluminum, aluminum oxide, aluminum nitride, and silicon joints.

Facilities Engineering Applications Program: Lead Monitoring Strategies for Drinking Water Systems: Lessons Learned

DTIC Science & Technology

1991-02-01

significant amount of lead mobilization. Studies by Lyson and Lenihan,ŝ Wong and Berrang,2 ° and Ierrra, t al.2’ describe this action and document the...Karaleka,. Jr. 1m I) V. Dc err , c a). T. Lyson and J. Lcnihan. ’Corrosion in Solder Jointed Copper tbes Resulting in Lead Contamination of Drinking...Boston Area," Journal of the New England Water Works Association, Vol 90 (1976). Lyson , T., and J. Lenihan, "Corrosion in Solder Jointed Copper Tubes

Quantitative method of determining beryllium or a compound thereof in a sample

DOEpatents

McCleskey, T. Mark; Ehler, Deborah S.; John, Kevin D.; Burrell, Anthony K.; Collis, Gavin E.; Minogue, Edel M.; Warner, Benjamin P.

2006-10-31

A method of determining beryllium or a beryllium compound thereof in a sample, includes providing a sample suspected of comprising beryllium or a compound thereof, extracting beryllium or a compound thereof from the sample by dissolving in a solution, adding a fluorescent indicator to the solution to thereby bind any beryllium or a compound thereof to the fluorescent indicator, and determining the presence or amount of any beryllium or a compound thereof in the sample by measuring fluorescence.

Quantitative method of determining beryllium or a compound thereof in a sample

DOEpatents

McCleskey, T. Mark; Ehler, Deborah S.; John, Kevin D.; Burrell, Anthony K.; Collis, Gavin E.; Minogue, Edel M.; Warner, Benjamin P.

2010-08-24

A method of determining beryllium or a beryllium compound thereof in a sample, includes providing a sample suspected of comprising beryllium or a compound thereof, extracting beryllium or a compound thereof from the sample by dissolving in a solution, adding a fluorescent indicator to the solution to thereby bind any beryllium or a compound thereof to the fluorescent indicator, and determining the presence or amount of any beryllium or a compound thereof in the sample by measuring fluorescence.

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

DOEpatents

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

1999-01-01

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

Self-diffusivity and interdiffusivity of molten aluminum-copper alloys under pressure, derived from molecular dynamics.

PubMed

Rudd, Robert E; Cabot, William H; Caspersen, Kyle J; Greenough, Jeffrey A; Richards, David F; Streitz, Frederick H; Miller, Paul L

2012-03-01

We use molecular dynamics (MD) to simulate diffusion in molten aluminum-copper (AlCu) alloys. The self-diffusivities and Maxwell-Stefan diffusivities are calculated for AlCu mixtures using the Green-Kubo formulas at temperatures from 1000 to 4000 K and pressures from 0 to 25 GPa, along with additional points at higher temperatures and pressures. The diffusivities are corrected for finite-size effects. The Maxwell-Stefan diffusivity is compared to the diffusivity calculated from the self-diffusivities using a generalization of the Darken equation. We find that the effects of cross-correlation are small. Using the calculated self-diffusivities, we have assessed whether dilute hard-sphere and dilute Lennard-Jones models apply to the molten mixture. Neither of the two dilute gas diffusivities describes the diffusivity in molten Al and Cu. We report generalized analytic models for the self-diffusivities and interdiffusivity (mutual diffusivity) that fit the MD results well. The MD-derived transport coefficients are in good agreement with the available experimental data. We also report MD calculations of the viscosity and an analytic fit to those results. The ionic thermal conductivity is discussed briefly.

Self-diffusivity and interdiffusivity of molten aluminum-copper alloys under pressure, derived from molecular dynamics

NASA Astrophysics Data System (ADS)

Rudd, Robert E.; Cabot, William H.; Caspersen, Kyle J.; Greenough, Jeffrey A.; Richards, David F.; Streitz, Frederick H.; Miller, Paul L.

2012-03-01

We use molecular dynamics (MD) to simulate diffusion in molten aluminum-copper (AlCu) alloys. The self-diffusivities and Maxwell-Stefan diffusivities are calculated for AlCu mixtures using the Green-Kubo formulas at temperatures from 1000 to 4000 K and pressures from 0 to 25 GPa, along with additional points at higher temperatures and pressures. The diffusivities are corrected for finite-size effects. The Maxwell-Stefan diffusivity is compared to the diffusivity calculated from the self-diffusivities using a generalization of the Darken equation. We find that the effects of cross-correlation are small. Using the calculated self-diffusivities, we have assessed whether dilute hard-sphere and dilute Lennard-Jones models apply to the molten mixture. Neither of the two dilute gas diffusivities describes the diffusivity in molten Al and Cu. We report generalized analytic models for the self-diffusivities and interdiffusivity (mutual diffusivity) that fit the MD results well. The MD-derived transport coefficients are in good agreement with the available experimental data. We also report MD calculations of the viscosity and an analytic fit to those results. The ionic thermal conductivity is discussed briefly.

Electron beam welding of copper-Monel facilitated by circular magnetic shields

NASA Technical Reports Server (NTRS)

Lamb, J. N.

1966-01-01

High permeability, soft magnetic rings are placed on both sides of electron beam weld seams in copper-Monel circular joint. This eliminates deflection of the electron beam caused by magnetic fields present in the weld area.

Integral window/photon beam position monitor and beam flux detectors for x-ray beams

DOEpatents

Shu, Deming; Kuzay, Tuncer M.

1995-01-01

A monitor/detector assembly in a synchrotron for either monitoring the position of a photon beam or detecting beam flux may additionally function as a vacuum barrier between the front end and downstream segment of the beamline in the synchrotron. A base flange of the monitor/detector assembly is formed of oxygen free copper with a central opening covered by a window foil that is fused thereon. The window foil is made of man-made materials, such as chemical vapor deposition diamond or cubic boron nitrate and in certain configurations includes a central opening through which the beams are transmitted. Sensors of low atomic number materials, such as aluminum or beryllium, are laid on the window foil. The configuration of the sensors on the window foil may be varied depending on the function to be performed. A contact plate of insulating material, such as aluminum oxide, is secured to the base flange and is thereby clamped against the sensor on the window foil. The sensor is coupled to external electronic signal processing devices via a gold or silver lead printed onto the contact plate and a copper post screw or alternatively via a copper screw and a copper spring that can be inserted through the contact plate and coupled to the sensors. In an alternate embodiment of the monitor/detector assembly, the sensors are sandwiched between the window foil of chemical vapor deposition diamond or cubic boron nitrate and a front foil made of similar material.

Beryllium--important for national defense

USGS Publications Warehouse

Boland, M.A.

2012-01-01

Beryllium is one of the lightest and stiffest metals, but there was little industrial demand for it until the 1930s and 1940s when the aerospace, defense, and nuclear sectors began using beryllium and its compounds. Beryllium is now classified by the U.S. Department of Defense as a strategic and critical material because it is used in products that are vital to national security. The oxide form of beryllium was identified in 1797, and scientists first isolated metallic beryllium in 1828. The United States is the world's leading source of beryllium. A single mine at Spor Mountain, Utah, produced more than 85 percent of the beryllium mined worldwide in 2010. China produced most of the remainder, and less than 2 percent came from Mozambique and other countries. National stockpiles also provide significant amounts of beryllium for processing. To help predict where future beryllium supplies might be located, U.S.Geological Survey (USGS) scientists study how and where beryllium resources are concentrated in Earth's crust and use that knowledge to assess the likelihood that undiscovered beryllium resources may exist. Techniques to assess mineral resources have been developed by the USGS to support the stewardship of Federal lands and to better evaluate mineral resource availability in a global context. The USGS also compiles statistics and information on the worldwide supply of, demand for, and flow of beryllium. These data are used to inform U.S. national policymaking.

METHOD OF MAKING ALLOYS OF BERYLLIUM WITH PLUTONIUM AND THE LIKE

DOEpatents

Runnals, O.J.C.

1959-02-24

The production of alloys of beryllium with one or more of the metals uranium, plutonium, actinium, americium, curium, thorium, and cerium are described. A halide salt of the metal to be alloyed with the beryllium is heated at 1300 deg C in the presence of beryllium to reduce the halide to metal and cause the latter to alloy directly with the beryllium. Although the heavy metal halides are more stable, thermodynamically, than the beryllium halides, the reducing reaction proceeds to completion if the beryllium halide product is continuously removed by vacuum distillation.

Potential exposures and risks from beryllium-containing products.

PubMed

Willis, Henry H; Florig, H Keith

2002-10-01

Beryllium is the strongest of the lightweight metals. Used primarily in military applications prior to the end of the Cold War, beryllium is finding new applications in many commercial products, including computers, telecommunication equipment, and consumer and automotive electronics. The use of beryllium in nondefense consumer applications is of concern because beryllium is toxic. Inhalation of beryllium dust or vapor causes a chronic lung disease in some individuals at concentrations as low as 0.01 microg/m3 in air. As beryllium enters wider commerce, it is prudent to ask what risks this might present to the general public and to workers downstream of the beryllium materials industry. We address this question by evaluating the potential for beryllium exposure from the manufacturing, use, recycle, and disposal of beryllium-containing products. Combining a market study with a qualitative exposure analysis, we determine which beryllium applications and life cycle phases have the largest exposure potential. Our analysis suggests that use and maintenance of the most common types of beryllium-containing products do not result in any obvious exposures of concern, and that maintenance activities result in greater exposures than product use. Product disposal has potential to present significant individual risks, but uncertainties concerning current and future routes of product disposal make it difficult to be definitive. Overall, additional exposure and dose-response data are needed to evaluate both the health significance of many exposure scenarios, and the adequacy of existing regulations to protect workers and the public. Although public exposures to beryllium and public awareness and concern regarding beryllium risks are currently low, beryllium risks have psychometric qualities that may lead to rapidly heightened public concern.

Atomistic modeling and simulation of the role of Be and Bi in Al diffusion in U-Mo fuel

NASA Astrophysics Data System (ADS)

Hofman, G. L.; Bozzolo, G.; Mosca, H. O.; Yacout, A. M.

2011-07-01

Within the RERTR program, previous experimental and modeling studies identified Si as the alloying addition to the Al cladding responsible for inhibiting Al interdiffusion in the UMo fuel. However, difficulties with reprocessing have rendered this choice inappropriate, leading to the need to study alternative elements. In this work, we discuss the results of an atomistic modeling effort which allows for the systematic study of several possible alloying additions. Based on the behavior observed in the phase diagrams, beryllium or bismuth additions suggest themselves as possible options to replace Si. The results of temperature-dependent simulations using the Bozzolo-Ferrante-Smith (BFS) method for the energetics for varying concentrations of either element are shown, indicating that Be could have a substantial effect in stopping Al interdiffusion, while Bi does not. Details of the calculations and the dependence of the role of each alloying addition as a function of temperature and concentration (of beryllium or bismuth in Al) are shown.

Development and evaluation of thin semi-rigid cables for superconducting detectors

NASA Astrophysics Data System (ADS)

Kasai, Soichi; Kushino, Akihiro

2015-03-01

We are developing semi-rigid cables for accurate readout of superconducting radiation/particle detectors and other low temperature experiments. The center conductor with a diameter of 0.86 mm is separated with seamless metal outer conductor by dielectric material, polytetrafluoroethylene. We used various metal materials with low thermal conductivity for the electrical conductors such as stainless-steel, cupro-nickel, brass, beryllium-copper, phosphor-bronze, niobium-titanium, and niobium. In addition to the conventional semi-rigid cables, low-pass-filter-type cables were manufactured and evaluated to cut the high frequency noise into superconducting detectors. We measured their low thermal conductance and attenuation property up to 10GHz below the liquid helium temperature.

Development of semi-rigid cables for low temperature superconducting detectors

NASA Astrophysics Data System (ADS)

Kushino, Akihiro; Kasai, Soichi

We are developing semi-rigid cables for accurate readout of superconducting radiation/particle detectors and other low temperature experiments. The center conductor with a diameter of 0.86 mm is separated with seamless metal outer conductor by dielectric material, polytetrafluoroethylene. We used various metal materials with low thermal conductivity for the electrical conductors such as stainless-steel, cupro-nickel, brass, beryllium-copper, phosphor-bronze, niobium-titanium, and niobium. In addition to the conventional semi-rigid cables, low-pass-filter type cables were manufactured and evaluated to cut the high frequency noise into superconducting detectors. We measured their low thermal conductance and attenuation property up to 10 GHz below the liquid helium temperature.

Ultrasonic Polishing

NASA Technical Reports Server (NTRS)

Gilmore, Randy

1993-01-01

The ultrasonic polishing process makes use of the high-frequency (ultrasonic) vibrations of an abradable tool which automatically conforms to the work piece and an abrasive slurry to finish surfaces and edges on complex, highly detailed, close tolerance cavities in materials from beryllium copper to carbide. Applications range from critical deburring of guidance system components to removing EDM recast layers from aircraft engine components to polishing molds for forming carbide cutting tool inserts or injection molding plastics. A variety of materials including tool steels, carbides, and even ceramics can be successfully processed. Since the abradable tool automatically conforms to the work piece geometry, the ultrasonic finishing method described offers a number of important benefits in finishing components with complex geometries.

Beryllium chemical speciation in elemental human biological fluids.

PubMed

Sutton, Mark; Burastero, Stephen R

2003-09-01

The understanding of beryllium chemistry in human body fluids is important for understanding the prevention and treatment of chronic beryllium disease. Thermodynamic modeling has traditionally been used to study environmental contaminant migration and rarely in the examination of metal (particularly beryllium) toxicology. In this work, a chemical thermodynamic speciation code (MINTEQA2) has been used to model and understand the chemistry of beryllium in simulated human biological fluids such as intracellular, interstitial, and plasma fluids, a number of airway surface fluids for patients with lung conditions, saliva, sweat, urine, bile, gastric juice, and pancreatic fluid. The results show that predicted beryllium solubility and speciation vary markedly between each simulated biological fluid. Formation of beryllium hydroxide and/or phosphate was observed in most of the modeled fluids, and results support the postulation that beryllium absorption in the gastrointestinal tract may be limited by the formation of beryllium phosphate solids. It is also postulated that beryllium is potentially 13% less soluble in the airway surface fluid of a patient with asthma when compared to a "normal" case. The results of this work, supported by experimental validation, can aid in the understanding of beryllium toxicology. Our results can potentially be applied to assessing the feasibility of biological monitoring or chelation treatment of beryllium body burden.

Application of diffuse discharges of atmospheric pressure formed by runaway electrons for modification of copper and stainless steel surface

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

Tarasenko, V. F., E-mail: VFT@loi.hcei.tsc.ru; Shulepov, M. A.; Erofeev, M. V.

The results of studies devoted to the influence of a runaway electron pre-ionized diffuse discharge (REP DD) formed in air and nitrogen at atmospheric pressure on the surface of copper and stainless steel are presented. Nanosecond high-voltage pulses were used to obtain REP DD in different gases at high pressures in a chamber with a flat anode and a cathode possessing a small radius of curvature. This mode of discharge was implemented owing to the generation of runaway electrons and X-rays. The conditions under which the surface of copper and stainless steel was cleaned from carbon and oxidized are described.

Initial stages of benzotriazole adsorption on the Cu(111) surface

NASA Astrophysics Data System (ADS)

Grillo, Federico; Tee, Daniel W.; Francis, Stephen M.; Früchtl, Herbert; Richardson, Neville V.

2013-05-01

Benzotriazole (BTAH) has been used as a copper corrosion inhibitor since the 1950s; however, the molecular level detail of how inhibition occurs remains a matter of debate. The onset of BTAH adsorption on a Cu(111) single crystal was investigated via scanning tunnelling microscopy (STM), vibrational spectroscopy (RAIRS) and supporting DFT modelling. BTAH adsorbs as anionic (BTA-), CuBTA is a minority species, while Cu(BTA)2, the majority of the adsorbed species, form chains, whose sections appear to diffuse in a concerted manner. The copper surface appears to reconstruct in a (2 × 1) fashion.Benzotriazole (BTAH) has been used as a copper corrosion inhibitor since the 1950s; however, the molecular level detail of how inhibition occurs remains a matter of debate. The onset of BTAH adsorption on a Cu(111) single crystal was investigated via scanning tunnelling microscopy (STM), vibrational spectroscopy (RAIRS) and supporting DFT modelling. BTAH adsorbs as anionic (BTA-), CuBTA is a minority species, while Cu(BTA)2, the majority of the adsorbed species, form chains, whose sections appear to diffuse in a concerted manner. The copper surface appears to reconstruct in a (2 × 1) fashion. Electronic supplementary information (ESI) available: Calculated IR spectra, RAIRS assignments, modeling details, statistics on diffusion, experimental details, additional STM images, movie low coverage diffusing species. See DOI: 10.1039/c3nr00724c

Beryllium contamination inside vehicles of machine shop workers

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

Sanderson, W.T.; Henneberger, P.K.; Martyny, J.

1999-04-01

Inhalation of beryllium particles causes a chronic, debilitating lung disease--chronic beryllium disease (CBD)--in immunologically sensitized workers. Evidence that very low concentrations of beryllium may initiate this chronic disease is provided by incidences of the illness in family members exposed to beryllium dust from workers` clothes and residents in neighborhoods surrounding beryllium refineries. This article describes the results of a cross-sectional survey to evaluate potential take-home beryllium exposures by measuring surface concentrations on the hands and in vehicles of workers at a precision machine shop where cases of CBD had recently been diagnosed. Many workers did not change out of theirmore » work clothes and shoes at the end of their shift, increasing the risk of taking beryllium home to their families. Wipe samples collected from workers` hands and vehicle surfaces were analyzed for beryllium content by inductively coupled argon plasma-atomic emission spectroscopy (ICP-AES). The results ranged widely, from nondetectable to 40 {micro}g/ft{sup 2} on workers` hands and up to 714 {micro}g/fg{sup 2} inside their vehicles, demonstrating that many workers carried residual beryllium on their hands and contaminated the inside of their vehicles when leaving work. The highest beryllium concentrations inside the workers` vehicles were found on the drivers` floor (GM = 19 {micro}g/ft{sup 2}, GSD = 4.9), indicating that workers were carrying beryllium on their shoes into their vehicles. A safe level of beryllium contamination on surfaces is not known, but it is prudent to reduce the potential for workers to carry beryllium away from the work site.« less

Beryllium health effects in the era of the beryllium lymphocyte proliferation test.

PubMed

Maier, L A

2001-05-01

The beryllium lymphocyte proliferation test (BeLPT) has revolutionized our approach to the diagnosis, screening, and surveillance of beryllium health effects. Based on the development of a beryllium-specific cell-mediated immune response, the BeLPT has allowed us to define early health effects of beryllium, including beryllium sensitization (BeS), and chronic beryllium disease (CBD) at a subclinical stage. The use of this test as a screening tool has improved our understanding of these health effects. From a number of studies it is apparent that BeS precedes CBD and develops after as little as 9 weeks of beryllium exposure. CBD occurs within 3 months and up to 30 years after initial beryllium exposure. Exposure-response variables have been associated with BeS/CBD, including work as a machinist, chemical or metallurgical operator, laboratory technician, work in ceramics or beryllium metal production, and years of beryllium exposure. Recent studies have found BeS and CBD in workplaces in which the majority of exposures were below the 2 microg/m3 OSHA time-weighted average (TWA). Ideally, the BeLPT would be used in surveillance aimed at defining other risk-related processes, determining exposure variables which predict BeS and CBD, and defining the exposure level below which beryllium health effects do not occur. Unfortunately, the BeLPT can result in false negative tests and still requires an invasive procedure, a bronchoscopy, for the definitive diagnosis of CBD. Thus, research is needed to establish new tests to be used alone or in conjunction with the BeLPT to improve our ability to detect early beryllium health effects.

10 CFR 850.20 - Baseline beryllium inventory.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 4 2010-01-01 2010-01-01 false Baseline beryllium inventory. 850.20 Section 850.20 Energy... Baseline beryllium inventory. (a) The responsible employer must develop a baseline inventory of the locations of beryllium operations and other locations of potential beryllium contamination, and identify the...

40 CFR 63.11166 - What General Provisions apply to primary beryllium production facilities?

Code of Federal Regulations, 2010 CFR

2010-07-01

... Primary Nonferrous Metals Area Sources-Zinc, Cadmium, and Beryllium Primary Beryllium Production Facilities § 63.11166 What General Provisions apply to primary beryllium production facilities? (a) You must... primary beryllium production facilities? 63.11166 Section 63.11166 Protection of Environment ENVIRONMENTAL...

Study on copper kinetics in processing sulphide ore mixed with copper and zinc with sulfuric acid leaching under pressure

NASA Astrophysics Data System (ADS)

Wen-bo, LUO; Ji-kun, WANG; Yin, GAN

2018-01-01

Sulphide ore mixed with copper and zinc is processed with pressure acid leaching. Research is conducted on the copper kinetic. The stirring rate is set at 600 rpm which could eliminate the influence of external diffusions. Research is conducted on the factors affecting the copper leaching kinetic are temperature, pressure, concentration of sulfuric acid, particle size. The result shows that the apparent activity energy is 50.7 KJ/mol. We could determine that the copper leaching process is shrinking core model of chemical reaction control and work out the leaching equation.

An evaluation of the spring finger solder joints on SA1358-10 and SA2052-4 connector assemblies (MC3617,W87).

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

Kilgo, Alice C.; Vianco, Paul Thomas; Hlava, Paul Frank

2006-08-01

The SA1358-10 and SA2052-4 circular JT Type plug connectors are used on a number of nuclear weapons and Joint Test Assembly (JTA) systems. Prototype units were evaluated for the following specific defects associated with the 95Sn-5Sb (Sn-Sb, wt.%) solder joint used to attach the beryllium-copper (BeCu) spring fingers to the aluminum (Al) connector shell: (1) extended cracking within the fillet; (2) remelting of the solder joint during the follow-on, soldering step that attached the EMR adapter ring to the connector shell (and/or soldering the EMR shell to the adapter ring) that used the lower melting temperature 63Sn-37Pb (Sn-Pb) alloy; andmore » (3) spalling of the Cd (Cr) layer overplating layer from the fillet surface. Several pedigrees of connectors were evaluated, which represented older fielded units as well as those assemblies that were recently constructed at Kansas City Plant. The solder joints were evaluated that were in place on connectors made with the current soldering process as well as an alternative induction soldering process for attaching the EMR adapter ring to the shell. Very similar observations were made, which crossed the different pedigrees of parts and processes. The extent of cracking in the top side fillets varied between the different connector samples and likely the EMR adapter ring to the shell. Very similar observations were made, which crossed the different pedigrees of parts and processes. The extent of cracking in the top side fillets varied between the different connector samples and likely reflected the different extents to which the connector was mated to its counterpart assembly. In all cases, the spring finger solder joints on the SA1358-10 connectors were remelted as a result of the subsequent EMR adapter ring attachment process. Spalling of the Cd (Cr) overplating layer was also observed for these connectors, which was a consequence of the remelting activity. On the other hand, the SA2052-4 connector did not exhibit evidence of remelting of the spring finger solder joint. The Cd (Cr) layer did not show signs of spalling. These results suggested that, due to the size of the SA1358-10 connector, any of the former or current soldering processes used to attach the EMR adapter ring and/or EMR shell to the connector shell, requires a level of heat energy that will always result in the remelting of the spring finger solder joint attached with either the Sn-Ag or the Sn-Sb alloy. Lastly, it was construed that the induction soldering process, which is used to attach the EMR adapter ring onto the shell, was more likely to have caused the remelting event rather than the more localized heat source of the hand soldering iron used to attach the EMR shell to the adapter ring.« less

Method of making alloys of beryllium with plutonium and the like

DOEpatents

Runnals, O J.C.

1959-02-24

The production or alloys of beryllium with one or more of the metals uranium, plutonium, actinium, americium, curium, thorium, and cerium is described. A halide salt or the metal to be alloyed with the beryllium is heated at l3O0 deg C in the presence of beryllium to reduce the halide to metal and cause the latter to alloy directly with the beryllium. Although the heavy metal halides are more stable, thermodynamically, than the beryllium halides, the reducing reaction proceeds to completion if the beryllium halide product is continuously removed by vacuum distillation.

Beryllium R&D for blanket application

NASA Astrophysics Data System (ADS)

Donne, M. Dalle; Longhurst, G. R.; Kawamura, H.; Scaffidi-Argentina, F.

1998-10-01

The paper describes the main problems and the R&D for the beryllium to be used as neutron multiplier in blankets. As the four ITER partners propose to use beryllium in the form of pebbles for their DEMO relevant blankets (only the Russians consider the porous beryllium option as an alternative) and the ITER breeding blanket will use beryllium pebbles as well, the paper is mainly based on beryllium pebbles. Also the work on the chemical reactivity of fully dense and porous beryllium in contact with water steam is described, due to the safety importance of this point.

Beryllium processing technology review for applications in plasma-facing components

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

Castro, R.G.; Jacobson, L.A.; Stanek, P.W.

1993-07-01

Materials research and development activities for the International Thermonuclear Experimental Reactor (ITER), i.e., the next generation fusion reactor, are investigating beryllium as the first-wall containment material for the reactor. Important in the selection of beryllium is the ability to process, fabricate and repair beryllium first-wall components using existing technologies. Two issues that will need to be addressed during the engineering design activity will be the bonding of beryllium tiles in high-heat-flux areas of the reactor, and the in situ repair of damaged beryllium tiles. The following review summarizes the current technology associated with welding and joining of beryllium to itselfmore » and other materials, and the state-of-the-art in plasma-spray technology as an in situ repair technique for damaged beryllium tiles. In addition, a review of the current status of beryllium technology in the former Soviet Union is also included.« less

Solubility and chemistry of materials encountered by beryllium mine and ore extraction workers: relation to risk.

PubMed

Deubner, David C; Sabey, Philip; Huang, Wenjie; Fernandez, Diego; Rudd, Abigail; Johnson, William P; Storrs, Jason; Larson, Rod

2011-10-01

Beryllium mine and ore extraction mill workers have low rates of beryllium sensitization and chronic beryllium disease relative to the level of beryllium exposure. The objective was to relate these rates to the solubility and composition of the mine and mill materials. Medical surveillance and exposure data were summarized. Dissolution of BeO, ore materials and beryllium hydroxide, Be(OH)(2) was measured in synthetic lung fluid. The ore materials were more soluble than BeO at pH 7.2 and similar at pH 4.5. Be(OH)(2) was more soluble than BeO at both pH. Aluminum dissolved along with beryllium from ore materials. Higher solubility of beryllium ore materials and Be(OH)(2) at pH 7.2 might shorten particle longevity in the lung. The aluminum content of the ore materials might inhibit the cellular immune response to beryllium.

Risk-based approach for controlling beryllium exposure in a manufacturing environment

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

Gilmore, W. E.; Clawson, C. D.; Ellis, K. K.

There are many diverse uses for beryllium in both military and industrial applications. Unfortunately, there are certain worker health risks associated with the manufacture and production of beryllium products. Respiratory illnesses due to prolonged contact with beryllium particulate are of paramount concern. However, these health risks can be controlled provided that the appropriate protective measures to prevent worker exposure from beryllium are in place. But it is no1 always a straightforward process to identify exactly what the beryllium protective measures should be in order to realize a true risk savings. Without prudent attention to a systematic inquiry and suitable evaluativemore » criteria, a program for controlling beryllium health risks can be lacking in completeness and overall effectiveness. One approach that took into account the necessary ingredients for risk-based determination of beryllium protective measures was developed for a beryllium operation at a Department of Energy (DOE) facility. The methodological framework that was applied at this facility, as well as a discussion of the final beryllium protective measures that were determined by this approach will be presented. Regulatory aspects for working with beryllium, as well as a risk-assessment strategy for ranking beryllium-handling activities with respect to exposure potential will also be discussed. The presentation will conclude with a synopsis of lessons-learned as gleaned from this case study, as well as providing the participants with a constructive blueprint that can be adapted to other processes involving beryllium.« less

Mineralogical Evidence of Galvanic Corrosion in Domestic, Drinking Water Pipes

EPA Science Inventory

Drinking water distribution system (DWDS) piping contains numerous examples of galvanically-coupled metals (e.g., soldered copper pipe joints, copper-lead pipes joined during partial replacements of lead service lines). The possible role of galvanic corrosion in the release of l...

Beryllium Ignition Targets for Indirect Drive NIF Experiments

NASA Astrophysics Data System (ADS)

Simakov, A. N.; Wilson, D. C.; Yi, S. A.; Kline, J. L.; Salmonson, J. D.; Clark, D. S.; Milovich, J. L.; Marinak, M. M.; Callahan, D. A.

2013-10-01

Current NIF plastic capsules are under-performing, and alternate ablators are being investigated. Beryllium presents an attractive option, since it has lower opacity and therefore higher ablation rate, pressure, and velocity. Previous NIF Be designs assumed significantly better hohlraum performance than recently observed (e.g., 7.5 vs. 15-17% of back-scattered power and 1.0 vs. 0.85 main pulse's power multipliers) and employed less accurate atomic configuration models than currently used (XSN vs. DCA), and thus an updated design is required. We present a new, Rev. 6 Be ignition target design that employs the full NIF capacity (1.8 MJ, 520 TW) and uses a standard 5.75 mm gold hohlraum with 1.5 mg/cm3 of helium gas fill. The 1051 μm capsule features 180 μm of layered copper-doped (with the maximum of 3 atom-%) Be ablator and 90 μm of cryogenic deuterium-tritium fuel. The peak implosion velocity of 367 μm/ns results in 4.1 keV of no-burn ion temperature, 1.6 and 1.9 g/cm2 of fuel and total areal densities, respectively, and 20.6 MJ of fusion yield. The capsule demonstrates robust performance with surface/interface roughnesses up to 1.6 times larger that Rev. 3 specs. Work supported by the US Department of Energy.

Vectorization of copper complexes via biocompatible and biodegradable PLGA nanoparticles.

PubMed

Courant, T; Roullin, V G; Cadiou, C; Delavoie, F; Molinari, M; Andry, M C; Gafa, V; Chuburu, F

2010-04-23

A double emulsion-solvent diffusion approach with fully biocompatible materials was used to encapsulate copper complexes within biodegradable nanoparticles, for which the release kinetics profiles have highlighted their potential use for a prolonged circulating administration.

FAST copper for broadband access

NASA Astrophysics Data System (ADS)

Chiang, Mung; Huang, Jianwei; Cendrillon, Raphael; Tan, Chee Wei; Xu, Dahai

2006-10-01

FAST Copper is a multi-year, U.S. NSF funded project that started in 2004, and is jointly pursued by the research groups of Mung Chiang at Princeton University, John Cioffi at Stanford University, and Alexader Fraser at Fraser Research Lab, and in collaboration with several industrial partners including AT&T. The goal of the FAST Copper Project is to provide ubiquitous, 100 Mbps, fiber/DSL broadband access to everyone in the U.S. with a phone line. This goal will be achieved through two threads of research: dynamic and joint optimization of resources in Frequency, Amplitude, Space, and Time (thus the name 'FAST') to overcome the attenuation and crosstalk bottlenecks, and the integration of communication, networking, computation, modeling, and distributed information management and control for the multi-user twisted pair network.

Effect of Filler and Heat Treatment on the Physical and Mechanical Properties of the Brazed Joint between Carbide Tip and Steel

NASA Astrophysics Data System (ADS)

Winardi, Y.; Triyono; Wijayanta, A. T.

2017-02-01

In this study, the effect of filler and heat treatment on the physical and mechanical properties of the brazed joint carbide tip and steel was investigated. Tip carbide YG6 and low carbon steel (SS400) is joining by torch brazing with two filler metals, silver, and copper filler. Heat treatment was performed in induction furnace. Microstructure and shear strength of the brazed joint have been investigated. Many silver filler layer are formed on the surface of the base metal rather then using copper filler. The highest shear strength is achieved using a silver filler metal at temperatur 725°C. The highest shear load is 18.62 kN.

Process Of Bonding Copper And Tungsten

DOEpatents

Slattery, Kevin T.; Driemeyer, Daniel E.

1999-11-23

Process for bonding a copper substrate to a tungsten substrate by providing a thin metallic adhesion promoting film bonded to a tungsten substrate and a functionally graded material (FGM) interlayer bonding the thin metallic adhesion promoting film to the copper substrate. The FGM interlayer is formed by thermal plasma spraying mixtures of copper powder and tungsten powder in a varied blending ratio such that the blending ratio of the copper powder and the tungsten powder that is fed to a plasma torch is intermittently adjusted to provide progressively higher copper content/tungsten content, by volume, ratio values in the interlayer in a lineal direction extending from the tungsten substrate towards the copper substrate. The resulting copper to tungsten joint well accommodates the difference in the coefficient of thermal expansion of the materials.

Chronic Beryllium Disease

MedlinePlus

... Newman LS. Re-examination of the blood lymphocyte transformation test in the diagnosis of chronic beryllium disease. ... et al. A study on the beryllium Lymphocyte Transformation Test and the beryllium levels in working environment. ...

Prevalence of beryllium sensitization among aluminium smelter workers

PubMed Central

Slade, M. D.; Cantley, L. F.; Kirsche, S. R.; Wesdock, J. C.; Cullen, M. R.

2010-01-01

Background Beryllium exposure occurs in aluminium smelters from natural contamination of bauxite, the principal source of aluminium. Aims To characterize beryllium exposure in aluminium smelters and determine the prevalence rate of beryllium sensitization (BeS) among aluminium smelter workers. Methods A population of 3185 workers from nine aluminium smelters owned by four different aluminium-producing companies were determined to have significant beryllium exposure. Of these, 1932 workers participated in medical surveillance programmes that included the serum beryllium lymphocyte proliferation test (BeLPT), confirmation of sensitization by at least two abnormal BeLPT test results and further evaluation for chronic beryllium disease in workers with BeS. Results Personal beryllium samples obtained from the nine aluminium smelters showed a range of <0.01–13.00 μg/m3 time-weighted average with an arithmetic mean of 0.25 μg/m3 and geometric mean of 0.06 μg/m3. Nine workers were diagnosed with BeS (prevalence rate of 0.47%, 95% confidence interval = 0.21–0.88%). Conclusions BeS can occur in aluminium smelter workers through natural beryllium contamination of the bauxite and further concentration during the refining and smelting processes. Exposure levels to beryllium observed in aluminium smelters are similar to those seen in other industries that utilize beryllium. However, compared with beryllium-exposed workers in other industries, the rate of BeS among aluminium smelter workers appears lower. This lower observed rate may be related to a more soluble form of beryllium found in the aluminium smelting work environment as well as the consistent use of respiratory protection. PMID:20610489

Some Properties of Beryllium Oxide and Beryllium Oxide - Columbium Ceramals

NASA Technical Reports Server (NTRS)

Robards, C F; Gangler, J J

1951-01-01

High-temperature tensile and thermal-shock investigations were conducted on beryllium oxide and beryllium oxide plus columbium metal additions. X-ray diffraction and metallographic results are given. The tensile strength of 6150 pounds per square inch for beryllium oxide at 1800 degrees F compared favorably with the zirconia bodies previously tested. Additions of 2, 5, 8, 10, 12, and 15 percent by weight of columbium metal failed to improve the shock resistance over that of pure beryllium oxide.

Numerical modeling of friction welding of bi-metal joints for electrical applications

NASA Astrophysics Data System (ADS)

Velu, P. Shenbaga; Hynes, N. Rajesh Jesudoss

2018-05-01

In the manufacturing industries, and more especially in electrical engineering applications, the usage of non-ferrous materials plays a vital role. Today's engineering applications relies upon some of the significant properties such as a good corrosion resistance, mechanical properties, good heat conductivity and higher electrical conductivity. Copper-aluminum bi-metal joint is one such combination that meets the demands requirements for electrical applications. In this work, the numerical simulation of AA 6061 T6 alloy/Copper was carried out under joining conditions. By using this developed model, the temperature distribution along the length of the dissimilar joint is predicted and the time-temperature profile has also been generated. Besides, a Finite Element Model has been developed by using the numerical simulation Tool "ABAQUS". This developed FEM is helpful in predicting various output parameters during friction welding of this dissimilar joint combination.

Physicochemical characteristics of aerosol particles generated during the milling of beryllium silicate ores: implications for risk assessment.

PubMed

Stefaniak, Aleksandr B; Chipera, Steve J; Day, Gregory A; Sabey, Phil; Dickerson, Robert M; Sbarra, Deborah C; Duling, Mathew G; Lawrence, Robert B; Stanton, Marcia L; Scripsick, Ronald C

2008-01-01

Inhalation of beryllium dusts generated during milling of ores and cutting of beryl-containing gemstones is associated with development of beryllium sensitization and low prevalence of chronic beryllium disease (CBD). Inhalation of beryllium aerosols generated during primary beryllium production and machining of the metal, alloys, and ceramics are associated with sensitization and high rates of CBD, despite similar airborne beryllium mass concentrations among these industries. Understanding the physicochemical properties of exposure aerosols may help to understand the differential immunopathologic mechanisms of sensitization and CBD and lead to more biologically relevant exposure standards. Properties of aerosols generated during the industrial milling of bertrandite and beryl ores were evaluated. Airborne beryllium mass concentrations among work areas ranged from 0.001 microg/m(3) (beryl ore grinding) to 2.1 microg/m(3) (beryl ore crushing). Respirable mass fractions of airborne beryllium-containing particles were < 20% in low-energy input operation areas (ore crushing, hydroxide product drumming) and > 80% in high-energy input areas (beryl melting, beryl grinding). Particle specific surface area decreased with processing from feedstock ores to drumming final product beryllium hydroxide. Among work areas, beryllium was identified in three crystalline forms: beryl, poorly crystalline beryllium oxide, and beryllium hydroxide. In comparison to aerosols generated by high-CBD risk primary production processes, aerosol particles encountered during milling had similar mass concentrations, generally lower number concentrations and surface area, and contained no identifiable highly crystalline beryllium oxide. One possible explanation for the apparent low prevalence of CBD among workers exposed to beryllium mineral dusts may be that characteristics of the exposure material do not contribute to the development of lung burdens sufficient for progression from sensitization to CBD. In comparison to high-CBD risk exposures where the chemical nature of aerosol particles may confer higher bioavailability, respirable ore dusts likely confer considerably less. While finished product beryllium hydroxide particles may confer bioavailability similar to that of high-CBD risk aerosols, physical exposure factors (i.e., large particle sizes) may limit development of alveolar lung burdens.

Recent advances in understanding the biomolecular basis of chronic beryllium disease: a review.

PubMed

McCleskey, T Mark; Buchner, Virginia; Field, R William; Scott, Brian L

2009-01-01

In this review we summarize the work conducted over the past decade that has advanced our knowledge of pulmonary diseases associated with exposure to beryllium that has provided a molecular-based understanding of the chemistry, immunopathology, and immunogenetics of beryllium toxicity. Beryllium is a strong and lightweight metal that generates and reflects neutrons, resists corrosion, is transparent to X-rays, and conducts electricity. Beryllium is one of the most toxic elements on the periodic table, eliciting in susceptible humans (a) an allergic immune response known as beryllium sensitization (BeS); (b) acute beryllium disease, an acutely toxic, pneumonitis-like lung condition resulting from exposure to high beryllium concentrations that are rarely seen in modern industry; and (c) chronic beryllium disease (CBD) following either high or very low levels of exposure. Because of its exceptional strength, stability, and heat-absorbing capability, beryllium is used in many important technologies in the modern world. In the early 1940s, beryllium was recognized as posing an occupational hazard in manufacturing and production settings. Although acute beryllium disease is now rare, beryllium is an insidious poison with a latent toxicity and the risk of developing CBD persists. Chronic beryllium disease-a systemic granulomatous lung disorder caused by a specific delayed immune response to beryllium within a few months to several decades after exposure-has been called the "unrecognized epidemic". Although not a disease in itself, BeS, the innate immune response to beryllium identified by an abnormal beryllium lymphocyte proliferation test result, is a population-based predictor of CBD. Genetic susceptibility to CBD is associated with alleles of the major histocompatibility gene, human leukocyte antigen DP (HLA-DP) containing glutamic acid at the 69th position of the beta chain (HLA-DPbeta-E69). Other genes are likely to be involved in the disease process, and research on this issue is in progress. The current Occupational Safety & Health Administration permissible exposure limit of 2 microg/m3 has failed to protect workers from BeS/CBD. As a safe exposure limit that will not lead to BeS or CBD has not yet been determined, the realization that the risk of CBD persists has led to a renaissance in research on the effects of the metal on human health. Current data support further reductions in exposure levels to help minimize the incidence of CBD. Steps that would directly impact both the power of epidemiologic studies and the cost of surveillance would be to develop and validate improved screening and diagnostic tests, and to identify more genetic factors that affect either sensitization or disease process. The major focus of this review is the recent research on the cellular and molecular basis of beryllium sensitization and disease, using a multidisciplinary approach of bioinorganic chemistry and immunology. First we present a historical background of beryllium exposure and disease, followed by occurrence of beryllium in the environment, toxicokinetics, biological effects, beryllium lung disease, and other human health effects.

Surface Modification of C17200 Copper-Beryllium Alloy by Plasma Nitriding of Cu-Ti Gradient Film

NASA Astrophysics Data System (ADS)

Zhu, Y. D.; Yan, M. F.; Zhang, Y. X.; Zhang, C. S.

2018-03-01

In the present work, a copper-titanium film of gradient composition was firstly fabricated by the dual magnetron sputtering through power control and plasma nitriding of the film was then conducted to modify C17200 Cu alloy. The results showed that the prepared gradient Cu-Ti film by magnetron sputtering was amorphous. After plasma nitriding at 650 °C, crystalline Cu-Ti intermetallics appeared in the multi-phase coating, including CuTi2, Cu3Ti, Cu3Ti2 and CuTi. Moreover, even though the plasma nitriding duration of the gradient Cu-Ti film was only 0.5 h, the mechanical properties of the modified Cu surface were obviously improved, with the surface hardness enhanced to be 417 HV0.01, the wear rate to be 0.32 × 10-14 m3/Nm and the friction coefficient to be 0.075 at the load of 10 N, which are all more excellent than the C17200 Cu alloy. In addition, the wear mechanism also changed from adhesion wear for C17200 Cu substrate to abrasive wear for the modified surface.

The change in the diffusion of water in normal and degenerative lumbar intervertebral discs following joint mobilization compared to prone lying.

PubMed

Beattie, Paul F; Donley, Jonathan W; Arnot, Cathy F; Miller, Ronald

2009-01-01

Prospective, repeated measures obtained under treatment and control conditions. The purposes of this study were to provide preliminary evidence regarding the immediate change in the diffusion of water in the nuclear region of normal and degenerative lumbar intervertebral discs (IVDs) following a single session of lumbar joint mobilization, and to compare these findings to the immediate change in the diffusion of water following a 10-minute session of prone lying. There is conflicting evidence regarding the effectiveness and efficacy of lumbar joint mobilization. Increased knowledge of the physiologic effects of lumbar joint mobilization can lead to refinement of its clinical application. A total of 24 people (15 males and 9 females), ranging in age from 22 to 58 years, participated in this study. All subjects had a history of activity-limiting low back pain. Diffusion-weighted magnetic resonance images (DW-MRIs) were obtained immediately before and after a 10-minute session of lumbar joint mobilization. At least 1 month later, a second session was performed in which DW-MRIs were obtained immediately before and after a 10-minute session of prone lying. Following lumbar joint mobilization, a significant increase (P = .002) in the mean values for diffusion of water was observed within degenerative IVDs at L5-S1 (22.2% increase; effect size, 0.97). Degenerative IVDs at L1-2 to L4-5 and normal IVDs at L1-2 to L5-S1 did not demonstrate a change in diffusion following joint mobilization. Prone lying was not associated with a change in diffusion for normal or degenerative IVDs. The stimulus provided by lumbar joint mobilization may influence the diffusion of water in degenerative IVDs at L5-S1; however, these are preliminary findings and the relationship of these findings to pain and function needs further investigation.

Method for hot pressing beryllium oxide articles

DOEpatents

Ballard, Ambrose H.; Godfrey, Jr., Thomas G.; Mowery, Erb H.

1988-01-01

The hot pressing of beryllium oxide powder into high density compacts with little or no density gradients is achieved by employing a homogeneous blend of beryllium oxide powder with a lithium oxide sintering agent. The lithium oxide sintering agent is uniformly dispersed throughout the beryllium oxide powder by mixing lithium hydroxide in an aqueous solution with beryllium oxide powder. The lithium hydroxide is converted in situ to lithium carbonate by contacting or flooding the beryllium oxide-lithium hydroxide blend with a stream of carbon dioxide. The lithium carbonate is converted to lithium oxide while remaining fixed to the beryllium oxide particles during the hot pressing step to assure uniform density throughout the compact.

Joint simulation of stationary grade and non-stationary rock type for quantifying geological uncertainty in a copper deposit

NASA Astrophysics Data System (ADS)

Maleki, Mohammad; Emery, Xavier

2017-12-01

In mineral resources evaluation, the joint simulation of a quantitative variable, such as a metal grade, and a categorical variable, such as a rock type, is challenging when one wants to reproduce spatial trends of the rock type domains, a feature that makes a stationarity assumption questionable. To address this problem, this work presents methodological and practical proposals for jointly simulating a grade and a rock type, when the former is represented by the transform of a stationary Gaussian random field and the latter is obtained by truncating an intrinsic random field of order k with Gaussian generalized increments. The proposals concern both the inference of the model parameters and the construction of realizations conditioned to existing data. The main difficulty is the identification of the spatial correlation structure, for which a semi-automated algorithm is designed, based on a least squares fitting of the data-to-data indicator covariances and grade-indicator cross-covariances. The proposed models and algorithms are applied to jointly simulate the copper grade and the rock type in a Chilean porphyry copper deposit. The results show their ability to reproduce the gradual transitions of the grade when crossing a rock type boundary, as well as the spatial zonation of the rock type.

Modern Chemistry Techniques Applied to Metal Behavior and Chelation in Medical and Environmental Systems ? Final Report

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

Sutton, M; Andresen, B; Burastero, S R

2005-02-03

This report details the research and findings generated over the course of a 3-year research project funded by Lawrence Livermore National Laboratory (LLNL) Laboratory Directed Research and Development (LDRD). Originally tasked with studying beryllium chemistry and chelation for the treatment of Chronic Beryllium Disease and environmental remediation of beryllium-contaminated environments, this work has yielded results in beryllium and uranium solubility and speciation associated with toxicology; specific and effective chelation agents for beryllium, capable of lowering beryllium tissue burden and increasing urinary excretion in mice, and dissolution of beryllium contamination at LLNL Site 300; {sup 9}Be NMR studies previously unstudied atmore » LLNL; secondary ionization mass spec (SIMS) imaging of beryllium in spleen and lung tissue; beryllium interactions with aerogel/GAC material for environmental cleanup. The results show that chelator development using modern chemical techniques such as chemical thermodynamic modeling, was successful in identifying and utilizing tried and tested beryllium chelators for use in medical and environmental scenarios. Additionally, a study of uranium speciation in simulated biological fluids identified uranium species present in urine, gastric juice, pancreatic fluid, airway surface fluid, simulated lung fluid, bile, saliva, plasma, interstitial fluid and intracellular fluid.« less

Dissolution characteristics of sericite in chalcopyrite bioleaching and its effect on copper extraction

NASA Astrophysics Data System (ADS)

Dong, Ying-bo; Li, Hao; Lin, Hai; Zhang, Yuan

2017-04-01

The effects of sericite particle size, rotation speed, and leaching temperature on sericite dissolution and copper extraction in a chalcopyrite bioleaching system were examined. Finer particles, appropriate temperature and rotation speed for Acidithiobacillus ferrooxidans resulted in a higher Al3+ dissolution concentration. The Al3+ dissolution concentration reached its highest concentration of 38.66 mg/L after 48-d leaching when the sericite particle size, temperature, and rotation speed were -43 μm, 30°C, and 160 r/min, respectively. Meanwhile, the sericite particle size, rotation speed, and temperature can affect copper extraction. The copper extraction rate is higher when the sericite particle size is finer. An appropriately high temperature is favorable for copper leaching. The dissolution of sericite fitted the shrinking core model, 1-(2/3) α-(1- α)2/3 = k 1 t, which indicates that internal diffusion is the decision step controlling the overall reaction rate in the leaching process. Scanning electron microscopy analysis showed small precipitates covered on the surface of sericite after leaching, which increased the diffusion resistance of the leaching solution and dissolved ions.

Hollow spherical rotors fabricated by electroplating

NASA Technical Reports Server (NTRS)

Avery, H. W.; Conroy, T. F.

1966-01-01

Equatorial bands are fabricated to provide a locating fit for the hemispheres of hollow spherical rotors which are then jointed by electroplating. Several nonmagnetic materials may be used to form the joint, such as aluminum, copper, iron, gold, plantinum, and zinc.

Influence of the volume-contact area ratio on the growth behavior of the Cu-Sn intermetallic phase

NASA Astrophysics Data System (ADS)

Giddaluri, Venkatakamakshi Supraja

Solder Joints play a very important role in electronic packaging industry by serving as mechanical support and provides integrity to the device. The increasing demand for high performance, environmental and economic feasibility and miniaturization led to the development of high density interconnects. With the reduction in the size/standoff height of the solder reliability issues in the surface mount assemblies and packaging structures under various rigorous environments are becoming significant. One of the most important impact factors that affect the solder joint reliability is the growth rate IMC formed between the solder and substrate with reduction in joint size. IMC formation is required to ensure good bonding and connectivity of the device in packaging. However excess IMC growth rate is detrimental to the device from mechanical aspects due to its brittle nature. Thus there is a need to study effect the IMC growth rate behavior with the solder joint size/standoff height. In this present study, two solder joints of different standoff heights and same composition (pure Sn solder) are used subjected to reflow process at 270°C for 1--7 min to study solid liquid interfacial reaction on joint size and the same experiment is repeated with SAC alloy of composition (96.5% Sn, 3.0% Ag, 0.5% Cu) to investigate the effect of joint size and initial copper concentration on IMC growth rate. The IMC thickness of the Sn 15microm solder joint at 1 min and 7 min is found to be 1.52microm and 2.86microm respectively while that of Sn 150microm solder joint is 1.31microm and 3.16 microm. The thickness is high in low standoff height sample at the early stage of reaction with decrease in IMC growth rate as the time of reflow increases. In case of 25microm SAC alloy solder joint the IMC thickness from 1 and 7 min is found to be 2.1microm and 3.5microm while that of 250microm SAC alloy solder joint its 1.43microm and3.235microm. Similar trend is observed but the IMC thickness is more in SAC alloy compared to Pure Sn due to initial Cu concentration effect. The CGC model is applied for growth kinetics of IMC formation and is in well agreement with the experimental results. It is found that the low standoff height solder joint follow t1/3 law and high standoff height solder joint deviates from the t1/3 due to unsaturation. The pure Sn solder of two different standoff heights is also subjected to isothermal aging tests at 120°C for 0--600 hours to investigate the effect of IMC growth rate on solder joint size in solid state diffusion. It has been found that low solder joint height is having high growth rate compared to high standoff height joint and it is found to obey parabolic law and follow reaction diffusion control mechanism.

The isotopic composition of cosmic-ray beryllium and its implication for the cosmic ray's age

NASA Technical Reports Server (NTRS)

Lukasiak, A.; Ferrando, P.; Mcdonald, F. B.; Webber, W. R.

1994-01-01

We report a new measurement of the cosmic-ray isotopic composition of beryllium in the low-energy range from 35 to 113 MeV per nucleon. This measurement was made using the High Energy Telescope of the CRS experiment on the Voyager 1 and 2 spacecraft during the time period from 1977 to 1991. In this overall time period of 14 years the average solar modulation level was about 500 MV. The cosmic-ray beryllium isotopes were completely separated with an average mass resolution sigma of 0.185 amu. The isotope fractions of Be-7, Be-9, and Be-10 obtained are 52.4 +/- 2.9%, 43.3 +/- 3.7%, and 4.3 +/- 1.5%, respectively. The measured cosmic-ray abundances of Be-7 and Be-9 are found to be in agreement with calculations based on standard Leaky-Box model for the interstellar propagation of cosmic-ray nuclei using the recent cross sections of the New Mexico-Saclay collaboration. From our observed ratio Be-10/Be = 4.3 +/- 1.5% we deduce an average interstellar density of about 0.28 (+0.14, -0.11) atoms/cu cm, and acosmic-ray lifetime for escape of 27 (+19, -9) x 10(exp 6) years. The surviving fraction of Be-10 is found to be 0.19 +/- 0.07. Modifications to the conclusions of the Leaky-Box model when a diffusion + convection halo model for propagation is used are also considered.

The isotopic composition of cosmic-ray beryllium and its implication for the cosmic ray's age

NASA Astrophysics Data System (ADS)

Lukasiak, A.; Ferrando, P.; McDonald, F. B.; Webber, W. R.

1994-03-01

We report a new measurement of the cosmic-ray isotopic composition of beryllium in the low-energy range from 35 to 113 MeV per nucleon. This measurement was made using the High Energy Telescope of the CRS experiment on the Voyager 1 and 2 spacecraft during the time period from 1977 to 1991. In this overall time period of 14 years the average solar modulation level was about 500 MV. The cosmic-ray beryllium isotopes were completely separated with an average mass resolution sigma of 0.185 amu. The isotope fractions of Be-7, Be-9, and Be-10 obtained are 52.4 +/- 2.9%, 43.3 +/- 3.7%, and 4.3 +/- 1.5%, respectively. The measured cosmic-ray abundances of Be-7 and Be-9 are found to be in agreement with calculations based on standard Leaky-Box model for the interstellar propagation of cosmic-ray nuclei using the recent cross sections of the New Mexico-Saclay collaboration. From our observed ratio Be-10/Be = 4.3 +/- 1.5% we deduce an average interstellar density of about 0.28 (+0.14, -0.11) atoms/cu cm, and a cosmic-ray lifetime for escape of 27 (+19, -9) x 106 years. The surviving fraction of Be-10 is found to be 0.19 +/- 0.07. Modifications to the conclusions of the Leaky-Box model when a diffusion + convection halo model for propagation is used are also considered.

Beryllium surface levels in a military ammunition plant.

PubMed

Sanderson, Wayne T; Leonard, Stephanie; Ott, Darrin; Fuortes, Laurence; Field, William

2008-07-01

This study evaluated the presence of beryllium surface contamination in a U.S. conventional munitions plant as an indicator of possible past beryllium airborne and skin exposure and used these measurements to classify job categories by potential level of exposure. Surface samples were collected from production and nonproduction areas of the plant and at regional industrial reference sites with no known history of beryllium use. Surface samples of premoistened wiping material were analyzed for beryllium mass content using inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and results expressed as micrograms of beryllium per 100 square centimeters (micro g/100 cm(2)). Beryllium was detected in 87% of samples collected at the munitions plant and in 72% of the samples collected at regional reference sites. Two munitions plant samples from areas near sanders and grinders were above 3.0 micro g/100 cm(2) (U.S. Department of Energy surface contamination limit). The highest surface level found at the reference sites was 0.44 micro g/100 cm(2). Workers in areas where beryllium-containing alloy tools were sanded or ground, but not other work areas, may have been exposed to airborne beryllium concentrations above levels encountered in other industries where metal work is conducted. Surface sampling provided information useful for categorizing munitions plant jobs by level of past beryllium airborne and skin exposure and, subsequently, for identifying employees within exposure strata to be screened for beryllium sensitization.

Synergy and Diffusion with a Borax-Copper Hydroxide Groundline Preservative: 20 Year Update

Treesearch

Stan Lebow; Bessie Woodward; Bill Abbott; Mike West

2014-01-01

A groundline remedial treatment containing 3.1% copper hydroxide (2% elemental copper) and 40% sodium tetraborate decahydrate (borax) was applied to unseasoned pine posts prior to placement in a test site in southern Mississippi. The soundness of the posts was periodically evaluated using a push test. After 3.5, 6.5, 10, 15 and 20 years, sections were taken from two...

20 CFR 30.206 - How does a claimant prove that the employee was a “covered beryllium employee” exposed to...

Code of Federal Regulations, 2014 CFR

2014-04-01

... was a âcovered beryllium employeeâ exposed to beryllium dust, particles or vapor in the performance of... beryllium dust, particles or vapor in the performance of duty? (a) Proof of employment at or physical... during a period when beryllium dust, particles, or vapor may have been present at such a facility, may be...

20 CFR 30.206 - How does a claimant prove that the employee was a “covered beryllium employee” exposed to...

Code of Federal Regulations, 2013 CFR

2013-04-01

... was a âcovered beryllium employeeâ exposed to beryllium dust, particles or vapor in the performance of... beryllium dust, particles or vapor in the performance of duty? (a) Proof of employment at or physical... during a period when beryllium dust, particles, or vapor may have been present at such a facility, may be...

20 CFR 30.206 - How does a claimant prove that the employee was a “covered beryllium employee” exposed to...

Code of Federal Regulations, 2010 CFR

2010-04-01

... was a âcovered beryllium employeeâ exposed to beryllium dust, particles or vapor in the performance of... beryllium dust, particles or vapor in the performance of duty? (a) Proof of employment at or physical... during a period when beryllium dust, particles, or vapor may have been present at such a facility, may be...

20 CFR 30.206 - How does a claimant prove that the employee was a “covered beryllium employee” exposed to...

Code of Federal Regulations, 2012 CFR

2012-04-01

... was a âcovered beryllium employeeâ exposed to beryllium dust, particles or vapor in the performance of... beryllium dust, particles or vapor in the performance of duty? (a) Proof of employment at or physical... during a period when beryllium dust, particles, or vapor may have been present at such a facility, may be...

20 CFR 30.206 - How does a claimant prove that the employee was a “covered beryllium employee” exposed to...

Code of Federal Regulations, 2011 CFR

2011-04-01

... was a âcovered beryllium employeeâ exposed to beryllium dust, particles or vapor in the performance of... beryllium dust, particles or vapor in the performance of duty? (a) Proof of employment at or physical... during a period when beryllium dust, particles, or vapor may have been present at such a facility, may be...

Assessment of personal airborne exposures and surface contamination from x-ray vaporization of beryllium targets at the National Ignition Facility.

PubMed

Paik, Samuel Y; Epperson, Patrick M; Kasper, Kenneth M

2017-06-01

This article presents air and surface sampling data collected over the first two years since beryllium was introduced as a target material at the National Ignition Facility. Over this time, 101 experiments with beryllium-containing targets were executed. The data provides an assessment of current conditions in the facility and a baseline for future impacts as new, reduced regulatory limits for beryllium are being proposed by both the Occupational Safety and Health Administration and Department of Energy. This study also investigates how beryllium deposits onto exposed surfaces as a result of x-ray vaporization and the effectiveness of simple decontamination measures in reducing the amount of removable beryllium from a surface. Based on 1,961 surface wipe samples collected from entrant components (equipment directly exposed to target debris) and their surrounding work areas during routine reconfiguration activities, only one result was above the beryllium release limit of 0.2 µg/100 cm 2 and 27 results were above the analytical reporting limit of 0.01 µg/100 cm 2 , for a beryllium detection rate of 1.4%. Surface wipe samples collected from the internal walls of the NIF target chamber, however, showed higher levels of beryllium, with beryllium detected on 73% and 87% of the samples during the first and second target chamber entries (performed annually), respectively, with 23% of the samples above the beryllium release limit during the second target chamber entry. The analysis of a target chamber wall panel exposed during the first 30 beryllium-containing experiments (cumulatively) indicated that 87% of the beryllium contamination remains fixed onto the surface after wet wiping the surface and 92% of the non-fixed contamination was removed by decontaminating the surface using a dry wipe followed by a wet wipe. Personal airborne exposures assessed during access to entrant components and during target chamber entry indicated that airborne beryllium was not present in workers' breathing zones. All the data thus far have shown that beryllium has been effectively managed to prevent exposures to workers during routine and non-routine work.

Assessment of personal airborne exposures and surface contamination from x-ray vaporization of beryllium targets at the National Ignition Facility

DOE PAGES

Paik, Samuel Y.; Epperson, Patrick M.; Kasper, Kenneth M.

2017-02-28

Here, this article presents air and surface sampling data collected over the first two years since beryllium was introduced as a target material at the National Ignition Facility. Over this time, 101 experiments with beryllium-containing targets were executed. The data provides an assessment of current conditions in the facility and a baseline for future impacts as new, reduced regulatory limits for beryllium are being proposed by both the Occupational Safety and Health Administration and Department of Energy. This study also investigates how beryllium deposits onto exposed surfaces as a result of x-ray vaporization and the effectiveness of simple decontamination measuresmore » in reducing the amount of removable beryllium from a surface. Based on 1,961 surface wipe samples collected from entrant components (equipment directly exposed to target debris) and their surrounding work areas during routine reconfiguration activities, only one result was above the beryllium release limit of 0.2 µg/100 cm 2 and 27 results were above the analytical reporting limit of 0.01 µg/100 cm 2, for a beryllium detection rate of 1.4%. Surface wipe samples collected from the internal walls of the NIF target chamber, however, showed higher levels of beryllium, with beryllium detected on 73% and 87% of the samples during the first and second target chamber entries (performed annually), respectively, with 23% of the samples above the beryllium release limit during the second target chamber entry. The analysis of a target chamber wall panel exposed during the first 30 beryllium-containing experiments (cumulatively) indicated that 87% of the beryllium contamination remains fixed onto the surface after wet wiping the surface and 92% of the non-fixed contamination was removed by decontaminating the surface using a dry wipe followed by a wet wipe. Personal airborne exposures assessed during access to entrant components and during target chamber entry indicated that airborne beryllium was not present in workers' breathing zones. Finally, all the data thus far have shown that beryllium has been effectively managed to prevent exposures to workers during routine and non-routine work.« less

Thermal shock induced oxidation of beryllium

NASA Astrophysics Data System (ADS)

Spilker, B.; Linke, J.; Pintsuk, G.; Wirtz, M.

2017-12-01

Beryllium has been chosen as a plasma facing material for the first wall of the experimental fusion reactor ITER, mainly because of its low atomic number and oxygen getter capabilities, which are favorable for a high plasma performance. While the steady state operational temperature of 250 °C has no deteriorating effect on the beryllium surface, transient plasma events can deposit power densities of up to 1 GW m-2 on the beryllium armor tiles. Previous research has shown that the oxidation of beryllium can occur under these thermal shock events. In the present study, S-65 grade beryllium specimens were exposed to 100 thermal shocks with an absorbed power density of 0.6 GW m-2 and a pulse duration of 1 ms, leading to a peak surface temperature of ˜800 °C. The induced surface morphology changes were compared to a steady state heated specimen at the same surface temperature with a holding time of 150 s. As a result, a pitting structure with an average pit diameter of ˜0.45 μm was observed on the thermal shock loaded surface, which was caused by beryllium oxide grain nucleation and subsequent erosion of the weakly bound beryllium oxide particles. In contrast, the steady state heated surface exhibited a more homogeneous beryllium oxide layer featuring small pits with diameters of tens of nm and showed the beryllium oxide grain nucleation in a beginning stage. The experiment demonstrated that thermal shock loading conditions can significantly accelerate the beryllium oxide grain nucleation. The resulting surface morphology change can potentially alter the fusion application relevant erosion, absorption, and retention characteristics of beryllium.

Process Waste Assessment Machine and Fabrication Shop

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

Phillips, N.M.

1993-03-01

This Process Waste Assessment was conducted to evaluate hazardous wastes generated in the Machine and Fabrication Shop at Sandia National Laboratories, Bonding 913, Room 119. Spent machine coolant is the major hazardous chemical waste generated in this facility. The volume of spent coolant generated is approximately 150 gallons/month. It is sent off-site to a recycler, but a reclaiming system for on-site use is being investigated. The Shop`s line management considers hazardous waste minimization very important. A number of steps have already been taken to minimize wastes, including replacement of a hazardous solvent with biodegradable, non-caustic solution and filtration unit; wastemore » segregation; restriction of beryllium-copper alloy machining; and reduction of lead usage.« less

An evaluation of the fatigue crack growth and fracture toughness properties of beryllium-copper alloy CDA172

NASA Technical Reports Server (NTRS)

Forman, Royce G.; Henkener, Julie A.

1990-01-01

A series of fracture mechanics tests, using the Be-Cu alloy CDA172 in the round rod product form, was conducted in a lab air environment at room temperature. Tensile data is presented in both the L and C directions and K sub Ic data in both the C-R and C-L orientations. Fracture toughness values were derived from M(T) (center cracked), PS(T) (surface cracked) and CC01 (corner cracked) specimens of varying thickness. Fatigue crack growth data were obtained for the C-R orientation at stress ratio of 0.1, 0.4, and 0.7 and for the C-L orientation at stress ratios of 0.1, 0.3, 0.4, and 0.7.

Mineral resource of the month: beryllium

USGS Publications Warehouse

,

2013-01-01

The article discusses information about Beryllium. It notes that Beryllium is a light metal that has a gray color. The metal is used in the production of parts and devices including bearings, computer-chip heat sinks, and output windows of X-ray tubes. The article mentions Beryllium's discovery in 1798 by French chemist, Louis-Nicolas Vanquelin. It cites that bertrandite and beryl are the principal mineral components for the commercial production of beryllium.

Proteomic analysis of beryllium-induced genotoxicity in an Escherichia coli mutant model system.

PubMed

Taylor-McCabe, Kirsten J; Wang, Zaolin; Sauer, Nancy N; Marrone, Babetta L

2006-03-01

Beryllium is the second lightest metal, has a high melting point and high strength-to-weight ratio, and is chemically stable. These unique chemical characteristics make beryllium metal an ideal choice as a component material for a wide variety of applications in aerospace, defense, nuclear weapons, and industry. However, inhalation of beryllium dust or fumes induces significant health effects, including chronic beryllium disease and lung cancer. In this study, the mutagenicity of beryllium sulfate (BeSO(4)) and the comutagenicity of beryllium with a known mutagen 1-methyl-3-nitro-1-nitrosoguanidine (MNNG) were evaluated using a forward mutant detection system developed in Escherichia coli. In this system, BeSO(4) was shown to be weakly mutagenic alone and significantly enhanced the mutagenicity of MNNG up to 3.5-fold over MNNG alone. Based on these results a proteomic study was conducted to identify the proteins regulated by BeSO(4). Using the techniques of 2-DE and oMALDI-TOF MS, we successfully identified 32 proteins being differentially regulated by beryllium and/or MNNG in the E. coli test system. This is the first study to describe the proteins regulated by beryllium in vitro, and the results suggest several potential pathways for the focus of further research into the mechanisms underlying beryllium-induced genotoxicity.

Electrochemical synthesis of copper nanoparticles using cuprous oxide as a precursor in choline chloride-urea deep eutectic solvent: nucleation and growth mechanism.

PubMed

Zhang, Q B; Hua, Y X

2014-12-28

The electrochemical nucleation and growth kinetics of copper nanoparticles on a Ni electrode have been studied with cyclic voltammetry and chronoamperometry in the choline chloride (ChCl)-urea based deep eutectic solvent (DES). The copper source was introduced into the solvent by the dissolution of Cu(I) oxide (Cu2O). Cyclic voltammetry indicates that the electroreduction of Cu(I) species in the DES is a diffusion-controlled quasi-reversible process. The analysis of the chronoamperometric transient behavior during electrodeposition suggests that the deposition of copper on the Ni electrode at low temperatures follows a progressive nucleation and three-dimensional growth controlled by diffusion. The effect of temperature on the diffusion coefficient of Cu(I) species that is present in the solvent and electron transfer rate constant obeys the Arrhenius law, according to which the activation energies are estimated to be 49.20 and 21.72 kJ mol(-1), respectively. The initial stage of morphological study demonstrates that both electrode potential and temperature play important roles in controlling the nucleation and growth kinetics of the nanocrystals during the electrodeposition process. Electrode potential is observed to affect mainly the nucleation process, whereas temperature makes a major contribution to the growth process.

Shielding gas effect to diffusion activities of magnesium and copper on aluminum clad

NASA Astrophysics Data System (ADS)

Manurung, Charles SP; Napitupulu, Richard AM

2017-09-01

Aluminum is the second most metal used in many application, because of its corrosion resistance. The Aluminum will be damaged in over time if it’s not maintained in good condition. That is important to give protection to the Aluminums surface. Cladding process is one of surface protection methodes, especially for metals. Aluminum clad copper (Al/Cu) or copper clad aluminum (Cu/Al) composite metals have been widely used for many years. These mature protection method and well tested clad metal systems are used industrially in a variety application. The inherent properties and behavior of both copper and aluminum combine to provide unique performance advantages. In this paper Aluminum 2024 series will be covered with Aluminum 1100 series by hot rolling process. Observations will focus on diffusion activities of Mg and Cu that not present on Aluminum 1100 series. The differences of clad material samples is the use of shielding gas during heating before hot rolling process. The metallurgical characteristics will be examined by using optical microscopy. Transition zone from the interface cannot be observed but from Energy Dispersive Spectrometry it’s found that Mg and Cu are diffused from base metal (Al 2024) to the clad metal (Al 1100). Hardness test proved that base metals hardness to interface was decrease.

Structural evidence for a copper-bound carbonate intermediate in the peroxidase and dismutase activities of superoxide dismutase.

PubMed

Strange, Richard W; Hough, Michael A; Antonyuk, Svetlana V; Hasnain, S Samar

2012-01-01

Copper-zinc superoxide dismutase (SOD) is of fundamental importance to our understanding of oxidative damage. Its primary function is catalysing the dismutation of superoxide to O(2) and H(2)O(2). SOD also reacts with H(2)O(2), leading to the formation of a strong copper-bound oxidant species that can either inactivate the enzyme or oxidise other substrates. In the presence of bicarbonate (or CO(2)) and H(2)O(2), this peroxidase activity is enhanced and produces the carbonate radical. This freely diffusible reactive oxygen species is proposed as the agent for oxidation of large substrates that are too bulky to enter the active site. Here, we provide direct structural evidence, from a 2.15 Å resolution crystal structure, of (bi)carbonate captured at the active site of reduced SOD, consistent with the view that a bound carbonate intermediate could be formed, producing a diffusible carbonate radical upon reoxidation of copper. The bound carbonate blocks direct access of substrates to Cu(I), suggesting that an adjunct to the accepted mechanism of SOD catalysed dismutation of superoxide operates, with Cu(I) oxidation by superoxide being driven via a proton-coupled electron transfer mechanism involving the bound carbonate rather than the solvent. Carbonate is captured in a different site when SOD is oxidised, being located in the active site channel adjacent to the catalytically important Arg143. This is the probable route of diffusion from the active site following reoxidation of the copper. In this position, the carbonate is poised for re-entry into the active site and binding to the reduced copper.

Structural Evidence for a Copper-Bound Carbonate Intermediate in the Peroxidase and Dismutase Activities of Superoxide Dismutase

PubMed Central

Strange, Richard W.; Hough, Michael A.; Antonyuk, Svetlana V.; Hasnain, S. Samar

2012-01-01

Copper-zinc superoxide dismutase (SOD) is of fundamental importance to our understanding of oxidative damage. Its primary function is catalysing the dismutation of superoxide to O2 and H2O2. SOD also reacts with H2O2, leading to the formation of a strong copper-bound oxidant species that can either inactivate the enzyme or oxidise other substrates. In the presence of bicarbonate (or CO2) and H2O2, this peroxidase activity is enhanced and produces the carbonate radical. This freely diffusible reactive oxygen species is proposed as the agent for oxidation of large substrates that are too bulky to enter the active site. Here, we provide direct structural evidence, from a 2.15 Å resolution crystal structure, of (bi)carbonate captured at the active site of reduced SOD, consistent with the view that a bound carbonate intermediate could be formed, producing a diffusible carbonate radical upon reoxidation of copper. The bound carbonate blocks direct access of substrates to Cu(I), suggesting that an adjunct to the accepted mechanism of SOD catalysed dismutation of superoxide operates, with Cu(I) oxidation by superoxide being driven via a proton-coupled electron transfer mechanism involving the bound carbonate rather than the solvent. Carbonate is captured in a different site when SOD is oxidised, being located in the active site channel adjacent to the catalytically important Arg143. This is the probable route of diffusion from the active site following reoxidation of the copper. In this position, the carbonate is poised for re-entry into the active site and binding to the reduced copper. PMID:22984565

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.)

In situ removal of copper from sediments by a galvanic cell.

PubMed

Yuan, Songhu; Wu, Chan; Wan, Jinzhong; Lu, Xiaohua

2009-01-01

This study dealt with in situ removal of copper from sediments through an electrokinetic (EK) process driven by a galvanic cell. Iron (Fe) and carbon (C) were placed separately and connected with a conductive wire. Polluted sediments were put between them and water was filled above the sediments. The galvanic cell was thus formed due to the different electrode potentials of Fe and C. The cell could remove the pollutants in the sediments by electromigration and/or electroosmosis. Results showed that a weak voltage less than 1V was formed by the galvanic cell. The voltage decreased with the increase of time. A slight increase of sediment pH from the anode (Fe) to the cathode (C) was observed. The presence of supernatant water inhibited the variation of sediment pH because H(+) and OH(-) could diffuse into the water. The removal of copper was affected by the sediment pH and the distribution of electrolyte in sediment and supernatant water. Lower pH led to higher removal efficiency. More electrolyte in the sediment and/or less electrolyte in the supernatant water favored the removal of copper. The major removal mechanism was proposed on the basis of the desorption of copper from sediment to pore solution and the subsequent electromigration of copper from the anode to the cathode. The diffusion of copper from sediment to supernatant water was negligible.

A demonstration of the antimicrobial effectiveness of various copper surfaces

PubMed Central

2013-01-01

Background Bacterial contamination on touch surfaces results in increased risk of infection. In the last few decades, work has been done on the antimicrobial properties of copper and its alloys against a range of micro-organisms threatening public health in food processing, healthcare and air conditioning applications; however, an optimum copper method of surface deposition and mass structure has not been identified. Results A proof-of-concept study of the disinfection effectiveness of three copper surfaces was performed. The surfaces were produced by the deposition of copper using three methods of thermal spray, namely, plasma spray, wire arc spray and cold spray The surfaces were then inoculated with meticillin-resistant Staphylococcus aureus (MRSA). After a two hour exposure to the surfaces, the surviving MRSA were assayed and the results compared. The differences in the copper depositions produced by the three thermal spray methods were examined in order to explain the mechanism that causes the observed differences in MRSA killing efficiencies. The cold spray deposition method was significantly more effective than the other methods. It was determined that work hardening caused by the high velocity particle impacts created by the cold spray technique results in a copper microstructure that enhances ionic diffusion, and copper ions are principally responsible for antimicrobial activity. Conclusions This test showed significant microbiologic differences between coatings produced by different spray techniques and demonstrates the importance of the copper application technique. The cold spray technique shows superior anti-microbial effectiveness caused by the high impact velocity imparted to the sprayed particles which results in high dislocation density and high ionic diffusivity. PMID:23537176

10 CFR 850.34 - Medical surveillance.

Code of Federal Regulations, 2010 CFR

2010-01-01

... beryllium-related health effects. (ii) The responsible employer must provide to beryllium-associated workers... physician who is familiar with the health effects of beryllium. (4) The responsible employer must establish... beryllium-related health effects. (2) Periodic evaluation. (i) The responsible employer must provide to...

10 CFR 850.33 - Beryllium emergencies.

Code of Federal Regulations, 2010 CFR

2010-01-01

... Beryllium emergencies. (a) The responsible employer must comply with 29 CFR 1910.120(l) for handling beryllium emergencies related to decontamination and decommissioning operations. (b) The responsible employer must comply with 29 CFR 1910.120(q) for handling beryllium emergencies related to all other...

Method of making crack-free zirconium hydride

DOEpatents

Sullivan, Richard W.

1980-01-01

Crack-free hydrides of zirconium and zirconium-uranium alloys are produced by alloying the zirconium or zirconium-uranium alloy with beryllium, or nickel, or beryllium and scandium, or nickel and scandium, or beryllium and nickel, or beryllium, nickel and scandium and thereafter hydriding.

Beryllium particle combustion

NASA Technical Reports Server (NTRS)

Prentice, J. L.

1972-01-01

A two-year study of the combustion efficiency of single beryllium droplets burning in a variety of oxidizers (primarily mixtures of oxygen/argon and oxygen/nitrogen) is summarized. An advanced laser heating technique was used to acquire systematic quantitative data on the burning of single beryllium droplets at atmospheric pressure. The research confirmed the sensitivity of beryllium droplet combustion to the chemistry of environmental species and provides experimental documentation for the nitrogen-induced droplet fragmentation of burning beryllium droplets.

Permanence and diffusion of borax-copper hydroxide remedial preservative applied to unseasoned pine posts : 10 year update

Treesearch

Douglas Crawford; Stan Lebow; Mike West; Bill Abbott

2005-01-01

In 1993, unseasoned pine posts were treated with groundline remedial treatment containing 3.1% copper hydroxide and 40% sodium tetraborate decahydrate (borax). The soundness of the posts was periodically evaluated using a push test. After 3.5, 6.5, and 10 years, sections were taken from two posts to determine retention of borax and copper hydroxide below ground to 36...

Validation of cleaning method for various parts fabricated at a Beryllium facility

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

Davis, Cynthia M.

This study evaluated and documented a cleaning process that is used to clean parts that are fabricated at a beryllium facility at Los Alamos National Laboratory. The purpose of evaluating this cleaning process was to validate and approve it for future use to assure beryllium surface levels are below the Department of Energy’s release limits without the need to sample all parts leaving the facility. Inhaling or coming in contact with beryllium can cause an immune response that can result in an individual becoming sensitized to beryllium, which can then lead to a disease of the lungs called chronic berylliummore » disease, and possibly lung cancer. Thirty aluminum and thirty stainless steel parts were fabricated on a lathe in the beryllium facility, as well as thirty-two beryllium parts, for the purpose of testing a parts cleaning method that involved the use of ultrasonic cleaners. A cleaning method was created, documented, validated, and approved, to reduce beryllium contamination.« less

Use of 41Ar production to measure ablator areal density in NIF beryllium implosions

DOE PAGES

Wilson, Douglas Carl; Cassata, W. S.; Sepke, S. M.; ...

2017-02-06

For the first time, 41Ar produced by the (n,Υ) reaction from 40Ar in the beryllium shell of a DT filled Inertial Confinement Fusion capsule has been measured. Ar is co-deposited with beryllium in the sputter deposition of the capsule shell. Combined with a measurement of the neutron yield, the radioactive 41Ar then quantifies the areal density of beryllium during the DT neutron production. Here, the measured 1.15 ± 0.17 × 10 +8 atoms of 41Ar are 2.5 times that from the best post-shot calculation, suggesting that the Ar and Be areal densities are correspondingly higher than those calculated. Possible explanationsmore » are that (1) the beryllium shell is compressed more than calculated, (2) beryllium has mixed into the cold DT ice, or more likely (3) less beryllium is ablated than calculated. Since only one DT filled beryllium capsule has been fielded at NIF, these results can be confirmed and expanded in the future.« less

Mineral Resources of the Wabayuma Peak Wilderness Study Area, Mohave County, Arizona

USGS Publications Warehouse

Conway, Clay M.; Hassemer, Jerry R.; Knepper, Daniel H.; Pitkin, James A.; Jachens, Robert C.; Chatman, Mark L.

1990-01-01

The Wabayuma Peak Wilderness Study Area (AZ-020-037/043), for which a mineral survey was requested by the U.S. Bureau of land Management, encompasses 40,118 acres in northwestern Arizona. Fieldwork was carried out in 1986-88 by the U.S. Bureau of Mines and the U.S. Geological Survey to appraise the identified (known) resources and assess the mineral resource potential (undiscovered) of the wilderness study area. Within the Wabayuma Peak Wilderness Study Area are 14 private parcels of land totaling 1,315 acres. The Wabayuma Peak Wilderness Study Area, including the 14 private parcels of land, is herein referred to as the 'wilderness study area' or the 'study area'. The Boriana, Antler, and Copper World mines lie near the east boundary of the study area. The Boriana mine was a major tungsten-producing mine of the United States during World War II. The Antler and Copper World mines produced relatively small amounts of copper and zinc prior to 1970. Copper and zinc were mined within 100 ft of the study area at the Antler mine. The Antler mine contains subeconomic resources of 350,000 to 400,000 short tons of copper-zinc ore; a minimum of 2,000 short tons, at grades of 1 to 4 percent copper and 1 to 2 percent zinc, lie within the study area. No other mineral resources were identified within the study area. Four small tracts in the eastern part and one in the central part of the study area have high resource potential for copper, zinc, and minor lead, silver, and gold in massive sulfide deposits. A large central tract and two eastern tracts have moderate resource potential for the same metals. An eastern and a western tract within the wilderness study area have high resource potential for tungsten, copper, and combinations of beryllium, gold, silver, arsenic, bismuth, molybdenum, tin, indium, thorium, niobium, yttrium, lanthanum, scandium, tantalum, rhenium, lead, zinc, and iron in granite-related tungsten-polymetallic vein deposits. Most of the rest of the study area has moderate resource potential for these metals. A northern tract in the study area has moderate resource potential for gold, copper, and combinations of silver, zinc, lead, tungsten, and molybdenum in polymetallic vein deposits of several types.

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

Paik, Samuel Y.; Epperson, Patrick M.; Kasper, Kenneth M.

Here, this article presents air and surface sampling data collected over the first two years since beryllium was introduced as a target material at the National Ignition Facility. Over this time, 101 experiments with beryllium-containing targets were executed. The data provides an assessment of current conditions in the facility and a baseline for future impacts as new, reduced regulatory limits for beryllium are being proposed by both the Occupational Safety and Health Administration and Department of Energy. This study also investigates how beryllium deposits onto exposed surfaces as a result of x-ray vaporization and the effectiveness of simple decontamination measuresmore » in reducing the amount of removable beryllium from a surface. Based on 1,961 surface wipe samples collected from entrant components (equipment directly exposed to target debris) and their surrounding work areas during routine reconfiguration activities, only one result was above the beryllium release limit of 0.2 µg/100 cm 2 and 27 results were above the analytical reporting limit of 0.01 µg/100 cm 2, for a beryllium detection rate of 1.4%. Surface wipe samples collected from the internal walls of the NIF target chamber, however, showed higher levels of beryllium, with beryllium detected on 73% and 87% of the samples during the first and second target chamber entries (performed annually), respectively, with 23% of the samples above the beryllium release limit during the second target chamber entry. The analysis of a target chamber wall panel exposed during the first 30 beryllium-containing experiments (cumulatively) indicated that 87% of the beryllium contamination remains fixed onto the surface after wet wiping the surface and 92% of the non-fixed contamination was removed by decontaminating the surface using a dry wipe followed by a wet wipe. Personal airborne exposures assessed during access to entrant components and during target chamber entry indicated that airborne beryllium was not present in workers' breathing zones. Finally, all the data thus far have shown that beryllium has been effectively managed to prevent exposures to workers during routine and non-routine work.« less

Thermal cycling tests on surface-mount assemblies

NASA Astrophysics Data System (ADS)

Jennings, C. W.

1988-03-01

The capability of surface-mount (SM) solder joints to withstand various thermal cycle stresses was evaluated through electrical circuit resistance changes of a test pattern and by visual examination for cracks in the solder after exposure to thermal cycling. The joints connected different electrical components, primarily leadless-chip carriers (LCCs), and printed wiring-board (PWB) pads on different laminate substrates. Laminate compositions were epoxy-glass and polyimide-glass with and without copper/Invar/copper (CIC) inner layers, polyimide-quartz, epoxy-Kevlar, and polyimide-Kevlar. The most resistant joints were between small LCCs (24 and 48 pins) and polyimide-glass laminate with CIC inner layers. Processing in joint formation was found to be an important part of joint resistant. Thermal cycling was varied with respect to both time and temperature. A few resistors, capacitors, and inductors showed opens after 500 30-min cycles between -65 C and 125 C. Appreciable moisture contents were measured for laminate materials, especially those of polyimide-Kevlar after equilibration in 100 percent relative humidity at room temperature. If not removed or reduced, moisture can cause delamination in vapor-phase soldering.

Modeling Airborne Beryllium Concentrations From Open Air Dynamic Testing

NASA Astrophysics Data System (ADS)

Becker, N. M.

2003-12-01

A heightened awareness of airborne beryllium contamination from industrial activities was reestablished during the late 1980's and early 1990's when it became recognized that Chronic Beryllium Disease (CBD) had not been eradicated, and that the Occupational Health and Safety Administration standards for occupational air exposure to beryllium may not be sufficiently protective. This was in response to the observed CBD increase in multiple industrial settings where beryllium was manufactured and/or machined, thus producing beryllium particulates which are then available for redistribution by airborne transport. Sampling and modeling design activities were expanded at Los Alamos National Laboratory in New Mexico to evaluate potential airborne beryllium exposure to workers who might be exposed during dynamic testing activities associated with nuclear weapons Stockpile Stewardship. Herein is presented the results of multiple types of collected air measurements that were designed to characterize the production and dispersion of beryllium used in components whose performance is evaluated during high explosive detonation at open air firing sites. Data from fallout, high volume air, medium volume air, adhesive film, particle size impactor, and fine-particulate counting techniques will be presented, integrated, and applied in dispersion modeling to assess potential onsite and offsite personal exposures resulting from dynamic testing activities involving beryllium.

Nickel aluminide-copper backing for butt joint welding

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

Raghavan, S.; Muszynski, M.; Chin, B.A.

1996-12-31

Single-side full penetration welding is the primary welding process in shipbuilding. This process requires the use of a backing to support the molten metal. Conventionally, copper has been used as the backing material in the shop and ceramic tiles for jobs on the field. However, copper has shown to contaminate the weld and produce adverse effects and ceramics have shown to produce porosities in the weld. A new backing with an intermetallic layer (NiAl) on the copper surface has been fabricated. The results indicate that this backing could alleviate the contamination problems and produce quality welds.

Modeling and Implementation of Solder-activated Joints for Single Actuator, Centimeter-Scale Robotic Mechanisms

DTIC Science & Technology

2010-06-01

Modulus Ratio Annealed Copper 1.0 1.0 1.0 6066 Aluminum 0.63 2.48 3.96 High-Temp Nitinol 0.68 16.8 24.7 1095 Spring Steel 1.82 16.5 9.08 106 5.2.2...were: copper, aluminum, Nitinol , and spring steel. The wetting ability of aluminum and Nitinol to lead-tin solders is poor. There are solders that have...32],[33]. Copper plating may be used to improve a material’s solderability. Nitinol and aluminum are not easily electroplated with copper. Steel and

Lung function, biological monitoring, and biological effect monitoring of gemstone cutters exposed to beryls

PubMed Central

Wegner, R.; Heinrich-Ramm, R.; Nowak, D.; Olma, K.; Poschadel, B.; Szadkowski, D.

2000-01-01

OBJECTIVES—Gemstone cutters are potentially exposed to various carcinogenic and fibrogenic metals such as chromium, nickel, aluminium, and beryllium, as well as to lead. Increased beryllium concentrations had been reported in the air of workplaces of beryl cutters in Idar-Oberstein, Germany. The aim of the survey was to study the excretion of beryllium in cutters and grinders with occupational exposure to beryls—for example, aquamarines and emeralds—to examine the prevalence of beryllium sensitisation with the beryllium lymphocyte transformation test (BeLT), to examine the prevalence of lung disease induced by beryllium, to describe the internal load of the respective metals relative to work process, and to screen for genotoxic effects in this particular profession.
METHODS—In a cross sectional investigation, 57 out of 100 gemstone cutters working in 12 factories in Idar-Oberstein with occupational exposure to beryls underwent medical examinations, a chest radiograph, lung function testing (spirometry, airway resistance with the interrupter technique), and biological monitoring, including measurements of aluminium, chromium, and nickel in urine as well as lead in blood. Beryllium in urine was measured with a newly developed direct electrothermal atomic absorption spectroscopy technique with a measurement limit of 0.06 µg/l. Also, cytogenetic tests (rates of micronuclei and sister chromatid exchange), and a BeLT were performed. Airborne concentrations of beryllium were measured in three factories. As no adequate local control group was available, the cutters were categorised into those with an exposure to beryls of >4 hours/week (group A) and ⩽4 hours/week (group B).
RESULTS—Clinical, radiological, or spirometric abnormalities indicating pneumoconiosis were detected in none of the gemstone cutters. Metal concentrations in biological material were far below the respective biological limit values, and beryllium in urine was only measurable in subjects of group A. Cytogenetic investigations showed normal values which were independent of the duration of beryllium exposure. In one subject, the BeLT was positive. Beryllium stimulation indices were significantly higher in subjects with detectable beryllium in the urine than in those with beryllium concentrations below the detection limit (p<0.05). In one factory, two out of four measurements of airborne beryllium concentrations were well above the German threshold limit value of 2 µg/m3 (twofold and 10-fold), and all gemstone cutters working in this factory had measurable beryllium concentrations in urine.
CONCLUSION—No adverse clinical health effects were found in this cross sectional investigation of gemstone cutters working with beryls. However, an improvement in workplace hygiene is recommended, accompanied by biological monitoring of beryllium in urine.


Keywords: gemstone cutter; beryllium in urine; lymphocyte transformation test PMID:10711282

A new Cu(GeNx) alloy film for industrial applications

NASA Astrophysics Data System (ADS)

Lin, Chon-Hsin

2014-11-01

In this study, a copper alloy [Cu(GeNx)] film is developed for industrial applications by cosputtering Cu and Ge targets on a barrierless Si substrate within a vacuum chamber sparsely filled with N2 gas. Through extensive tests conducted in this study, the alloy film shows good thermal stability and adhesion to the substrate with no noticeable interactions between the film and the substrate after annealing at 720 °C for 1 h. The new Cu(GeNx) alloy film also renders adequate wetting for solders, shows good solderability, and has a dissolution rate lower than pure Cu by at least one order of magnitude, in addition to having a comparable consumption rate to Ni. The alloy film seems suitable for industrial applications in, e.g., barrierless Si metallization, interconnect manufacture and, the replacement of the wetting and diffusion layers for flip-chip solder joints in conventional metallurgy.

46 CFR 119.730 - Nonferrous metallic piping materials.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Provisions must be made to protect piping systems using aluminum alloys in high risk fire areas due to the... galvanic corrosion due to the relative solution potentials of copper, aluminum, and alloys of copper and... suitable thread compound must be used in making up threaded joints in aluminum pipe to prevent seizing...

Beryllium Manufacturing Processes

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

Goldberg, A

2006-06-30

This report is one of a number of reports that will be combined into a handbook on beryllium. Each report covers a specific topic. To-date, the following reports have been published: (1) Consolidation and Grades of Beryllium; (2) Mechanical Properties of Beryllium and the Factors Affecting these Properties; (3) Corrosion and Corrosion Protection of Beryllium; (4) Joining of Beryllium; (5) Atomic, Crystal, Elastic, Thermal, Nuclear, and other Properties of Beryllium; and (6) Beryllium Coating (Deposition) Processes and the Influence of Processing Parameters on Properties and Microstructure. The conventional method of using ingot-cast material is unsuitable for manufacturing a beryllium product.more » Beryllium is a highly reactive metal with a high melting point, making it susceptible to react with mold-wall materials forming beryllium compounds (BeO, etc.) that become entrapped in the solidified metal. In addition, the grain size is excessively large, being 50 to 100 {micro}m in diameter, while grain sizes of 15 {micro}m or less are required to meet acceptable strength and ductility requirements. Attempts at refining the as-cast-grain size have been unsuccessful. Because of the large grain size and limited slip systems, the casting will invariably crack during a hot-working step, which is an important step in the microstructural-refining process. The high reactivity of beryllium together with its high viscosity (even with substantial superheat) also makes it an unsuitable candidate for precision casting. In order to overcome these problems, alternative methods have been developed for the manufacturing of beryllium. The vast majority of these methods involve the use of beryllium powders. The powders are consolidated under pressure in vacuum at an elevated temperature to produce vacuum hot-pressed (VHP) blocks and vacuum hot-isostatic-pressed (HIP) forms and billets. The blocks (typically cylindrical), which are produced over a wide range of sizes (up to 183 cm dia. by 61 cm high), may be cut or machined into parts or be thermomechanically processed to develop the desired microstructure, properties, and shapes. Vacuum hot-isostatic pressing and cold-isostatic pressing (CIP) followed by sintering and possibly by a final HIP'ing (CIP/Sinter/HIP) are important in their use for the production of near net-shaped parts. For the same starting powder, a HIP'ed product will have less anisotropy than that obtained for a VHP'ed product. A schematic presentation illustrating the difference between VHP'ing and HIP'ing is shown in Figure I-1. The types of powders and the various beryllium grades produced from the consolidated powders and their ambient-temperature mechanical properties were presented in the consolidation report referred to above. Elevated-temperature properties and the effect of processing variables on mechanical properties are described in the mechanical properties report. Beryllium can also be deposited as coatings as well as freestanding forms. The microstructure, properties, and various methods used that are related to the deposition of beryllium are discussed in the report on beryllium coatings.« less

Beryllium disease among construction trade workers at Department of Energy nuclear sites.

PubMed

Welch, Laura S; Ringen, Knut; Dement, John; Bingham, Eula; Quinn, Patricia; Shorter, Janet; Fisher, Miles

2013-10-01

A medical surveillance program was developed to identify current and former construction workers at significant risk for beryllium related disease from work at the DOE nuclear weapons facilities, and to improve surveillance among beryllium exposed workers. Medical examinations included a medical history and a beryllium blood lymphocyte proliferation test (BeLPT). Stratified and multivariate logistic regression analyses were used to explore the risk of disease by age, race, trade, and reported work in buildings where beryllium was used. After adjusting for covariates, the risk of BeS was significantly higher among boilermakers, roofers, and sheet metal workers, as suggested in the stratified analyses. Workers identified as sensitized to beryllium were interviewed to determine whether they had been subsequently diagnosed with chronic beryllium disease. Between 1998 and December 31, 2010 13,810 workers received a BeLPT through the BTMed program; 189 (1.4%) were sensitized to beryllium, and 28 reported that they had had a compensation claim accepted for CBD. These data on former construction workers gives us additional information about the predictive value of the blood BeLPT test for detection of CBD in populations with lower total lifetime exposures and more remote exposures than that experienced by current workers in beryllium machining operations. Through this surveillance program we have identified routes of exposures to beryllium and worked with DOE site personnel to identity and mitigate those exposures which still exist, as well as helping to focus attention on the risk for beryllium exposure among current demolition workers at these facilities. Copyright © 2013 Wiley Periodicals, Inc.

Underwater explosive compaction-sintering of tungsten-copper coating on a copper surface

NASA Astrophysics Data System (ADS)

Chen, Xiang; Li, Xiaojie; Yan, Honghao; Wang, Xiaohong; Chen, Saiwei

2018-01-01

This study investigated underwater explosive compaction-sintering for coating a high-density tungsten-copper composite on a copper surface. First, 50% W-50% Cu tungsten-copper composite powder was prepared by mechanical alloying. The composite powder was pre-compacted and sintered by hydrogen. Underwater explosive compaction was carried out. Finally, a high-density tungsten-copper coating was obtained by diffusion sintering of the specimen after explosive compaction. A simulation of the underwater explosive compaction process showed that the peak value of the pressure in the coating was between 3.0 and 4.8 GPa. The hardness values of the tungsten-copper layer and the copper substrate were in the range of 87-133 and 49 HV, respectively. The bonding strength between the coating and the substrate was approximately 100-105 MPa.

5. VIEW OF BERYLLIUM PROCESSING AREA, ROLLING MILL. BERYLLIUM FORMING ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

5. VIEW OF BERYLLIUM PROCESSING AREA, ROLLING MILL. BERYLLIUM FORMING BEGAN IN SIDE A OF THE BUILDING IN 1962. (11/5/73) - Rocky Flats Plant, Uranium Rolling & Forming Operations, Southeast section of plant, southeast quadrant of intersection of Central Avenue & Eighth Street, Golden, Jefferson County, CO

A base-metal conductor system for silicon solar cells

NASA Technical Reports Server (NTRS)

Coleman, M. G.; Pryor, R. A.; Sparks, T. G.

1980-01-01

Solder, copper, and silver are evaluated as conductor layer metals for silicon solar cell metallization on the basis of metal price stability and reliability under operating conditions. Due to its properties and cost, copper becomes an attractive candidate for the conductor layer. It is shown that nickel operates as an excellent diffusion barrier between copper and silicon while simultaneously serving as an electrical contact and mechanical contact to silicon. The nickel-copper system may be applied to the silicon by plating techniques utilizing a variety of plating bath compositions. Solar cells having excellent current-voltage characteristics are fabricated to demonstrate the nickel-copper metallization system.

The intermetallic formation and growth kinetics at the interface of near eutectic tin-silver-copper solder alloys and gold/nickel metallization

NASA Astrophysics Data System (ADS)

Gao, Mao

The formation of a one micron thick layer of an intermetallic compound between a solder alloy and a metallic substrate generally constitutes a good solder joint in an electronic device. However, if the compound grows too thick, and/or if multiple intermetallic compounds form, poor solder joint reliability may result. Thus significant interest has been focused on intermetallic compound phase selection and growth kinetics at such solder/metal interfaces. The present study focuses on one such specific problem, the formation and growth of intermetallic compounds at near eutectic Sn-Ag-Cu solder alloy/Ni interfaces. Sn-3.0Ag-0.5Cu solder was reflowed on Au/Ni substrates, resulting in the initial formation and growth of (CuNi)6Sn 5 at Sn-3.0Ag-0.5Cu /Ni interfaces. (NiCu)3Sn4 formed between the (CuNi)6Sn5 and the Ni substrate when the concentration of Cu in the liquid SnAgCu solder decreased to a critical value which depended upon temperature: 0.37, 0.31 and 0.3(wt.%) at reflow temperatures of 260°C, 245°C and 230°C respectively. The growth rate of (CuNi)6Sn5 was found to be consistent with extrapolations of a diffusion limited growth model formulated for lower temperature, solid state diffusion couples. The long range diffusion of Cu did not limit growth rates. The spalling of (CuNiAu)6Sn5 from (NiCu)3 Sn4 surfaces during reflow was also examined. When the Cu concentration in the solder decreased to approximately 0.28wt.%, the (Cu,Ni,Au) 6Sn5 was observed to spall. Compressive stress in (CuNiAu) 6Sn5 and weak adhesion between (CuNiAu)6Sn 5 and (NiCu)3Sn4 was found to cause this effect.

The Effect of Welding Energy on the Microstructural and Mechanical Properties of Ultrasonic-Welded Copper Joints

PubMed Central

Yang, Jingwei; Cao, Biao; Lu, Qinghua

2017-01-01

The effects of welding energy on the mechanical and microstructural characteristics of ultrasonic-welded pure copper plates were investigated. Complex dynamic recrystallization and grain growth occurred inside the weld zone during ultrasonic welding. At a low welding energy, a thin band of straight weld interfaces was observed and had an ultra-fine grain structure. With an increase in welding energy, the weld interface progressively changed from flat to sinusoidal, and eventually turned into a convoluted wavy pattern, bearing similarities to shear instabilities, as observed in fluid dynamics. The lap shear load of the joints initially increased and then remained stable as the welding energy increased. The tensile characteristics of the joints significantly depended on the development of plastic deformation at the interface. The influence of the microstructure on the hardness was also discussed. PMID:28772553

The Effect of Welding Energy on the Microstructural and Mechanical Properties of Ultrasonic-Welded Copper Joints.

PubMed

Yang, Jingwei; Cao, Biao; Lu, Qinghua

2017-02-16

The effects of welding energy on the mechanical and microstructural characteristics of ultrasonic-welded pure copper plates were investigated. Complex dynamic recrystallization and grain growth occurred inside the weld zone during ultrasonic welding. At a low welding energy, a thin band of straight weld interfaces was observed and had an ultra-fine grain structure. With an increase in welding energy, the weld interface progressively changed from flat to sinusoidal, and eventually turned into a convoluted wavy pattern, bearing similarities to shear instabilities, as observed in fluid dynamics. The lap shear load of the joints initially increased and then remained stable as the welding energy increased. The tensile characteristics of the joints significantly depended on the development of plastic deformation at the interface. The influence of the microstructure on the hardness was also discussed.

Evaluation of Defects inside Beryllium Foils using X-ray Computed Tomography and Shearing Interferometry

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

Sakurai, Tatsuyuki; Kohmura, Yoshiki; Takeuchi, Akihisa

2007-01-19

When beryllium is used in transmission X-ray optical elements for spatially coherent beams, speckles are usually observed in the transmission images. These speckles seem to be caused by defects either inside or on the surface of beryllium foil. We measured highly polished beryllium foil using two methods, X-ray computed tomography and X-ray shearing interferometry. The results indicate that observed speckle pattern is caused by many voids inside beryllium or inner low-density regions.

Determination of sedimentation, diffusion, and mixing rates in coastal sediments of the eastern Red Sea via natural and anthropogenic fallout radionuclides.

PubMed

Al-Mur, Bandar A; Quicksall, Andrew N; Kaste, James M

2017-09-15

The Red Sea is a unique ecosystem with high biodiversity in one of the warmest regions of the world. In the last five decades, Red Sea coastal development has rapidly increased. Sediments from continental margins are delivered to depths by advection and diffusion-like processes which are difficult to quantify yet provide invaluable data to researchers. Beryllium-7, lead-210 and ceseium-137 were analyzed from sediment cores from the near-coast Red Sea near Jeddah, Saudi Arabia. The results of this work are the first estimates of diffusion, mixing, and sedimentation rates of the Red Sea coastal sediments. Maximum chemical diffusion and particle mixing rates range from 69.1 to 380cm -2 y -1 and 2.54 to 6.80cm -2 y -1 , respectively. Sedimentation rate is constrained to approximately 0.6cm/yr via multiple methods. These data provide baselines for tracking changes in various environmental problems including erosion, marine benthic ecosystem silting, and particle-bound contaminant delivery to the seafloor. Copyright © 2017. Published by Elsevier Ltd.

20 CFR 30.615 - What type of tort suits filed against beryllium vendors or atomic weapons employers may...

Code of Federal Regulations, 2014 CFR

2014-04-01

... beryllium vendors or atomic weapons employers may disqualify certain claimants from receiving benefits under... Special Provisions Effect of Tort Suits Against Beryllium Vendors and Atomic Weapons Employers § 30.615 What type of tort suits filed against beryllium vendors or atomic weapons employers may disqualify...

20 CFR 30.615 - What type of tort suits filed against beryllium vendors or atomic weapons employers may...

Code of Federal Regulations, 2010 CFR

2010-04-01

... beryllium vendors or atomic weapons employers may disqualify certain claimants from receiving benefits under... Special Provisions Effect of Tort Suits Against Beryllium Vendors and Atomic Weapons Employers § 30.615 What type of tort suits filed against beryllium vendors or atomic weapons employers may disqualify...

20 CFR 30.615 - What type of tort suits filed against beryllium vendors or atomic weapons employers may...

Code of Federal Regulations, 2011 CFR

2011-04-01

... beryllium vendors or atomic weapons employers may disqualify certain claimants from receiving benefits under... Special Provisions Effect of Tort Suits Against Beryllium Vendors and Atomic Weapons Employers § 30.615 What type of tort suits filed against beryllium vendors or atomic weapons employers may disqualify...

20 CFR 30.615 - What type of tort suits filed against beryllium vendors or atomic weapons employers may...

Code of Federal Regulations, 2012 CFR

2012-04-01

... beryllium vendors or atomic weapons employers may disqualify certain claimants from receiving benefits under... Special Provisions Effect of Tort Suits Against Beryllium Vendors and Atomic Weapons Employers § 30.615 What type of tort suits filed against beryllium vendors or atomic weapons employers may disqualify...

20 CFR 30.615 - What type of tort suits filed against beryllium vendors or atomic weapons employers may...

Code of Federal Regulations, 2013 CFR

2013-04-01

... beryllium vendors or atomic weapons employers may disqualify certain claimants from receiving benefits under... Special Provisions Effect of Tort Suits Against Beryllium Vendors and Atomic Weapons Employers § 30.615 What type of tort suits filed against beryllium vendors or atomic weapons employers may disqualify...

METHOD FOR PREPARATION OF SINTERABLE BERYLLIUM OXIDE

DOEpatents

Sturm, B.J.

1963-08-13

High-purity beryllium oxide for nuclear reactor applications can be prepared by precipitation of beryllium oxalate monohydrate from aqueous solution at a temperature above 50 deg C and subsequent calcination of the precipitate. Improved purification with respect to metallic impurities is obtained, and the product beryllium oxide sinters reproducibly to a high density. (AEC)

Chronic beryllium disease in a precious metal refinery. Clinical epidemiologic and immunologic evidence for continuing risk from exposure to low level beryllium fumes

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

Cullen, M.R.; Kominsky, J.R.; Rossman, M.D.

1987-01-01

Five workers at a precious metal refinery developed granulomatous lung disease between 1972 and 1985. The original diagnosis was sarcoidosis, but 4 of the workers were subsequently proved to have hypersensitivity to beryllium by in vitro proliferative responses of lymphocytes obtained by bronchoalveolar lavage. Review of medical records of coworkers and extensive industrial hygiene surveillance of the plant demonstrated that 4 cases occurred in the furnace area where air concentrations of beryllium fume were consistently below the permissible exposure limit of 2 micrograms/M3. A single case has been recognized from parts of the refinery where exposures to cold beryllium dustmore » often exceeded the standard by as much as 20-fold. These data demonstrate that chronic beryllium disease still occurs and confirm the importance of specific immunologic testing in patients suspected of having sarcoidosis but with potential exposure to beryllium. The data raise concern about the adequacy of modern industrial controls, especially in the setting of exposure to highly respirable beryllium fumes.« less

Retention and diffusion of H, He, O, C impurities in Be

NASA Astrophysics Data System (ADS)

Zhang, Pengbo; Zhao, Jijun; Wen, Bin

2012-04-01

We report the energetics and diffusion behavior of H, He, O, and C impurities in beryllium as fusion materials from first-principles calculations. Among the six interstitial sites in Be, the basal tetrahedral one is most stable for H, He, O, while C prefers to occupy an octahedral site. Solution of O impurity in Be is an exothermic process with solution energy of -2.37 eV, whereas solution of H, C and He is an endothermic process (solution energy: 1.55 eV, 2.46 eV, and 5.70 eV, respectively). Overall speaking, these impurities prefer to diffuse along longer paths. The H and O impurities share the same out-of-plane diffusion path via basal tetrahedral sites, while the He and C impurities in Be mainly diffuse via basal tetrahedral and octahedral sites along the (0 0 1) plane. Diffusion of He in Be is easiest with a lowest barrier of 0.14 eV; whereas H diffusion in Be is also rather fast with migration energies of 0.4 eV. On the contrary, diffusion of C and O impurities is more difficult because of strong bonding with lattice atoms and high energy barriers of 0.42 and 1.63 eV, respectively. Our theoretical results provide the fundamental parameters for understanding the impurity aggregation and bubble formation in early stage of irradiation damage.

A durability test of wood posts in Hawaii...third progress report

Treesearch

Roger G. Skolmen

1971-01-01

Round posts of 10 Hawaii-grown wood species were treated with copper chromate-copper arsenate by the double-diffusion process. These and untreated posts were exposed for 10 years. Except with two coniferous species, the treatment did not lengthen service life enough to be judged worthwhile.

Screening for beryllium disease among construction trade workers at Department of Energy nuclear sites.

PubMed

Welch, Laura; Ringen, Knut; Bingham, Eula; Dement, John; Takaro, Tim; McGowan, William; Chen, Anna; Quinn, Patricia

2004-09-01

To determine whether current and former construction workers are at significant risk for occupational illnesses from work at the Department of Energy's (DOE) nuclear weapons facilities, screening programs were undertaken at the Hanford Nuclear Reservation, Oak Ridge Reservation, and the Savannah River Site. Medical examination for beryllium disease used a medical history and a beryllium blood lymphocyte proliferation test (BeLPT). Stratified and multivariate logistic regression analyses were used to explore the risk of disease by age, race, sex, trade, duration of DOE employment, reported work in buildings where beryllium was used, and time since last DOE site employment. Of the 3,842 workers included in this study, 34% reported exposure to beryllium. Overall, 2.2% of workers had at least one abnormal BeLPT test, and 1.4% were also abnormal on a second test. Regression analyses demonstrated increased risk of having at least one abnormal BeLPT to be associated with ever working in a site building where beryllium activities had taken place. The prevalence of beryllium sensitivity and chronic beryllium disease (CBD) in construction workers is described and the positive predictive value of the BeLPT in a population with less intense exposure to beryllium than other populations that have been screened is discussed. The BeLPT findings and finding of cases of CBD demonstrate that some of these workers had significant exposure, most likely, during maintenance, repair, renovation, or demolition in facilities where beryllium was used.

Inter-diffusion of copper and hafnium as studied by x-ray photoelectron spectroscopy

NASA Astrophysics Data System (ADS)

Pearson, Justin; Chourasia, A. R.

The Cu/Hf interface has been characterized by x-ray photoelectron spectroscopy. Thin films (thicknesses ranging from 100 nm to 150 nm) of hafnium were deposited on a silicon substrate. About 80 nm of copper was then deposited on such samples. The e-beam method was used for the deposition. The samples were annealed for 30 min at temperatures of 100, 200, 300, 400, and 500°C. The inter-diffusion of copper and hafnium was investigated by sequential sputter depth profiling and x-ray photoelectron spectroscopy. The interdiffusion in each case was analyzed by the Matano-Boltzmann's procedure using the Fick's second law. The interdiffusion coefficients and the width of the interface as determined from the data have been correlated with the annealing temperature. Supported by Organized Research, TAMU-Commerce.

Beryllium Metal II. A Review of the Available Toxicity Data

PubMed Central

Strupp, Christian

2011-01-01

Beryllium metal was classified in Europe collectively with beryllium compounds, e.g. soluble salts. Toxicological equivalence was assumed despite greatly differing physicochemical properties. Following introduction of the Registration, Evaluation, Authorization and Restriction of Chemicals (REACH) regulation, beryllium metal was classified as individual substance and more investigational efforts to appropriately characterize beryllium metal as a specific substance apart from soluble beryllium compounds was required. A literature search on toxicity of beryllium metal was conducted, and the resulting literature compiled together with the results of a recently performed study package into a comprehensive data set. Testing performed under Organisation for Economic Co-Operation and Development guidelines and Good Laboratory Practice concluded that beryllium metal was neither a skin irritant, an eye irritant, a skin sensitizer nor evoked any clinical signs of acute oral toxicity; discrepancies between the current legal classification of beryllium metal in the European Union (EU) and the experimental results were identified. Furthermore, genotoxicity and carcinogenicity were discussed in the context of the literature data and the new experimental data. It was concluded that beryllium metal is unlikely to be a classical nonthreshold mutagen. Effects on DNA repair and morphological cell transformation were observed but need further investigation to evaluate their relevance in vivo. Animal carcinogenicity studies deliver evidence of carcinogenicity in the rat; however, lung overload may be a species-specific confounding factor in the existing studies, and studies in other species do not give convincing evidence of carcinogenicity. Epidemiology has been intensively discussed over the last years and has the problem that the studies base on the same US beryllium production population and do not distinguish between metal and soluble compounds. It is noted that the correlation between beryllium exposure and carcinogenicity, even including the soluble compounds, remains under discussion in the scientific community and active research is continuing. PMID:21196456

Beryllium metal I. experimental results on acute oral toxicity, local skin and eye effects, and genotoxicity.

PubMed

Strupp, Christian

2011-01-01

The toxicity of soluble metal compounds is often different from that of the parent metal. Since no reliable data on acute toxicity, local effects, and mutagenicity of beryllium metal have ever been generated, beryllium metal powder was tested according to the respective Organisation for Economical Co-Operation and Development (OECD) guidelines. Acute oral toxicity of beryllium metal was investigated in rats and local effects on skin and eye in rabbits. Skin-sensitizing properties were investigated in guinea pigs (maximization method). Basic knowledge about systemic bioavailability is important for the design of genotoxicity tests on poorly soluble substances. Therefore, it was necessary to experimentally compare the capacities of beryllium chloride and beryllium metal to form ions under simulated human lung conditions. Solubility of beryllium metal in artificial lung fluid was low, while solubility in artificial lysosomal fluid was moderate. Beryllium chloride dissolution kinetics were largely different, and thus, metal extracts were used in the in vitro genotoxicity tests. Genotoxicity was investigated in vitro in a bacterial reverse mutagenicity assay, a mammalian cell gene mutation assay, a mammalian cell chromosome aberration assay, and an unscheduled DNA synthesis (UDS) assay. In addition, cell transformation was tested in a Syrian hamster embryo cell assay, and potential inhibition of DNA repair was tested by modification of the UDS assay. Beryllium metal was found not to be mutagenic or clastogenic based on the experimental in vitro results. Furthermore, treatment with beryllium metal extracts did not induce DNA repair synthesis, indicative of no DNA-damaging potential of beryllium metal. A cell-transforming potential and a tendency to inhibit DNA repair when the cell is severely damaged by an external stimulus were observed. Beryllium metal was also found not to be a skin or eye irritant, not to be a skin sensitizer, and not to have relevant acute oral toxic properties.

Quantification and micron-scale imaging of spatial distribution of trace beryllium in shrapnel fragments and metallurgic samples with correlative fluorescence detection method and secondary ion mass spectrometry (SIMS)

PubMed Central

Abraham, Jerrold L.; Chandra, Subhash; Agrawal, Anoop

2014-01-01

Recently, a report raised the possibility of shrapnel-induced chronic beryllium disease (CBD) from long-term exposure to the surface of retained aluminum shrapnel fragments in the body. Since the shrapnel fragments contained trace beryllium, methodological developments were needed for beryllium quantification and to study its spatial distribution in relation to other matrix elements, such as aluminum and iron, in metallurgic samples. In this work, we developed methodology for quantification of trace beryllium in samples of shrapnel fragments and other metallurgic sample-types with main matrix of aluminum (aluminum cans from soda, beer, carbonated water, and aluminum foil). Sample preparation procedures were developed for dissolving beryllium for its quantification with the fluorescence detection method for homogenized measurements. The spatial distribution of trace beryllium on the sample surface and in 3D was imaged with a dynamic secondary ion mass spectrometry (SIMS) instrument, CAMECA IMS 3f SIMS ion microscope. The beryllium content of shrapnel (~100 ppb) was the same as the trace quantities of beryllium found in aluminum cans. The beryllium content of aluminum foil (~25 ppb) was significantly lower than cans. SIMS imaging analysis revealed beryllium to be distributed in the form of low micron-sized particles and clusters distributed randomly in X-Y-and Z dimensions, and often in association with iron, in the main aluminum matrix of cans. These observations indicate a plausible formation of Be-Fe or Al-Be alloy in the matrix of cans. Further observations were made on fluids (carbonated water) for understanding if trace beryllium in cans leached out and contaminated the food product. A direct comparison of carbonated water in aluminum cans and plastic bottles revealed that beryllium was below the detection limits of the fluorescence detection method (~0.01 ppb). These observations indicate that beryllium present in aluminum matrix was either present in an immobile form or its mobilization into the food product was prevented by a polymer coating on the inside of cans, a practice used in food industry to prevent contamination of food products. The lack of such coating in retained shrapnel fragments renders their surface a possible source of contamination for long-term exposure of tissues and fluids and induction of disease, as characterized in a recent study. Methodological developments reported here can be extended to studies of beryllium in electronics devices and components. PMID:25146877

Quantification and micron-scale imaging of spatial distribution of trace beryllium in shrapnel fragments and metallurgic samples with correlative fluorescence detection method and secondary ion mass spectrometry (SIMS).

PubMed

Abraham, J L; Chandra, S; Agrawal, A

2014-11-01

Recently, a report raised the possibility of shrapnel-induced chronic beryllium disease from long-term exposure to the surface of retained aluminum shrapnel fragments in the body. Since the shrapnel fragments contained trace beryllium, methodological developments were needed for beryllium quantification and to study its spatial distribution in relation to other matrix elements, such as aluminum and iron, in metallurgic samples. In this work, we developed methodology for quantification of trace beryllium in samples of shrapnel fragments and other metallurgic sample-types with main matrix of aluminum (aluminum cans from soda, beer, carbonated water and aluminum foil). Sample preparation procedures were developed for dissolving beryllium for its quantification with the fluorescence detection method for homogenized measurements. The spatial distribution of trace beryllium on the sample surface and in 3D was imaged with a dynamic secondary ion mass spectrometry instrument, CAMECA IMS 3f secondary ion mass spectrometry ion microscope. The beryllium content of shrapnel (∼100 ppb) was the same as the trace quantities of beryllium found in aluminum cans. The beryllium content of aluminum foil (∼25 ppb) was significantly lower than cans. SIMS imaging analysis revealed beryllium to be distributed in the form of low micron-sized particles and clusters distributed randomly in X-Y- and Z dimensions, and often in association with iron, in the main aluminum matrix of cans. These observations indicate a plausible formation of Be-Fe or Al-Be alloy in the matrix of cans. Further observations were made on fluids (carbonated water) for understanding if trace beryllium in cans leached out and contaminated the food product. A direct comparison of carbonated water in aluminum cans and plastic bottles revealed that beryllium was below the detection limits of the fluorescence detection method (∼0.01 ppb). These observations indicate that beryllium present in aluminum matrix was either present in an immobile form or its mobilization into the food product was prevented by a polymer coating on the inside of cans, a practice used in food industry to prevent contamination of food products. The lack of such coating in retained shrapnel fragments renders their surface a possible source of contamination for long-term exposure of tissues and fluids and induction of disease, as characterized in a recent study. Methodological developments reported here can be extended to studies of beryllium in electronics devices and components. © 2014 The Authors Journal of Microscopy © 2014 Royal Microscopical Society.

Impact of Deepwater Horizon Oil Contamination on the Aqueous Geochemistry of Salt Marsh Sediment/Seawater Microcosms

NASA Astrophysics Data System (ADS)

Rentschler, E. K.; Donahoe, R. J.

2011-12-01

On April 20th, 2010, the Deepwater Horizon oil drilling rig, located in the Gulf of Mexico about 41 miles off the Louisiana coast, exploded, burned for two days, and sank. Approximately 4.9 million gallons of crude oil were released and traveled with ocean currents to reach the coasts of Louisiana, Mississippi, Alabama, and Florida. Previous studies have primarily considered the direct impact of oil and dispersant contamination on coastal ecosystems, but have not examined the potential impact of the accident on the inorganic geochemistry of coastal waters and sediments. In this study, microcosm experiments were conducted to determine how oil contamination will affect the concentration and distribution of trace elements in a salt marsh environment. Uncontaminated sediment and seawater, collected from a salt marsh at Bayou la Batre, Alabama, were measured into jars and spiked with 500 ppm MC-252 oil. Twenty jars, including duplicates and both sterile and non-sterile controls, were placed on a shaker table at 100 rpm. The jars were sacrificed at predetermined time intervals (0 h, 6 h, 12 h, 24 h, 48 h, 7 d, and 14 d), and the aqueous samples prepared for analysis by ICP-OES and IC. The pH for the water in the time series experiment ranged from 7.16 to 8.06. Seawater alkalinity was measured at 83.07 mg CaCO3/L. ICP-OES data show variations in aqueous element concentrations over the 14 day microcosm experiment. Significant positive correlations (>0.75) were found for the following pairs of elements: calcium and magnesium, calcium and sodium, magnesium and sodium, silica and boron, beryllium and boron, iron and silica, manganese and silica, boron and manganese, arsenic and nickel, beryllium and selenium, beryllium and zinc, copper and chloride, bromide and sulfate. Aqueous iron concentrations were highly correlated with solution pH. The presence of iron oxide and clays in the sediment indicates a potential for adsorption of trace elements sourced from the environment and from crude oil contamination. The release of aqueous Fe(II) between 2 to 14 days could be caused by desorption from, and/or by reductive dissolution of, iron-bearing clays or iron oxide. Metals associated with crude oil are releasing into the water at similar times. Cadmium and vanadium, metals commonly associated with crude oil, both increase in concentration six hours into the experiment, followed by another small peak after seven days. Other trace elements (nickel, copper, and zinc) are released after one day. Geochemical modeling is being used to interpret the aqueous geochemistry of the experiments.

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.

Effects of ultrasound and temperature on copper electro reduction in Deep Eutectic Solvents (DES).

PubMed

Mandroyan, Audrey; Mourad-Mahmoud, Mahmoud; Doche, Marie-Laure; Hihn, Jean-Yves

2014-11-01

This paper concerns a preliminary study for a new copper recovery process from ionic solvent. The aim of this work is to study the reduction of copper in Deep Eutectic Solvent (choline chloride-ethylene glycol) and to compare the influence of temperature and the ultrasound effects on kinetic parameters. Solutions were prepared by dissolution of chloride copper salt CuCl2 (to obtain Copper in oxidation degree II) or CuCl (to obtain Copper in oxidation degree I) and by leaching metallic copper directly in DES. The spectrophotometry UV-visible analysis of the leached solution showed that the copper soluble form obtained is at oxidation degree I (Copper I). Both cyclic voltammetry and linear voltammetry were performed in the three solutions at three temperatures (25, 50 and 80°C) and under ultrasonic conditions (F=20kHz, PT=5.8W) to calculate the mass transfer diffusion coefficient kD and the standard rate coefficient k°. These parameters are used to determine that copper reduction is carried out via a mixed kinetic-diffusion control process. Temperature and ultrasound have the same effect on mass transfer for reduction of Cu(II)/Cu(I). On the other hand, temperature is more beneficial than ultrasound for mass transfer of Cu(I)/Cu. Standard rate constant improvement due to temperature increase is of the same order as that obtained with ultrasound. But, by combining higher temperature and ultrasound (F=20kHz, PT=5.6W at 50°C), reduction limiting current is increased by a factor of 10 compared to initial conditions (T=25°C, silent), because ultrasonic stirring is more efficient in lower viscosity fluid. These values can be considered as key-parameters in the design of copper recovery in global processes using ultrasound. Copyright © 2014 Elsevier B.V. All rights reserved.

Copper-silver-titanium filler metal for direct brazing of structural ceramics

DOEpatents

Moorhead, Arthur J.

1987-01-01

A method of joining ceramics and metals to themselves and to one another is described using a brazing filler metal consisting essentially of 35 to 50 atomic percent copper, 15 to 50 atomic percent silver and 10 to 45 atomic percent titanium. This method produces strong joints that can withstand high service temperatures and oxidizing environments.

10 CFR Appendix A to Part 850 - Chronic Beryllium Disease Prevention Program Informed Consent Form

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 4 2010-01-01 2010-01-01 false Chronic Beryllium Disease Prevention Program Informed Consent Form A Appendix A to Part 850 Energy DEPARTMENT OF ENERGY CHRONIC BERYLLIUM DISEASE PREVENTION PROGRAM Pt. 850, App. A Appendix A to Part 850—Chronic Beryllium Disease Prevention Program Informed...

10 CFR Appendix A to Part 850 - Chronic Beryllium Disease Prevention Program Informed Consent Form

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 4 2011-01-01 2011-01-01 false Chronic Beryllium Disease Prevention Program Informed Consent Form A Appendix A to Part 850 Energy DEPARTMENT OF ENERGY CHRONIC BERYLLIUM DISEASE PREVENTION PROGRAM Pt. 850, App. A Appendix A to Part 850—Chronic Beryllium Disease Prevention Program Informed...

10 CFR Appendix A to Part 850 - Chronic Beryllium Disease Prevention Program Informed Consent Form

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 4 2013-01-01 2013-01-01 false Chronic Beryllium Disease Prevention Program Informed Consent Form A Appendix A to Part 850 Energy DEPARTMENT OF ENERGY CHRONIC BERYLLIUM DISEASE PREVENTION PROGRAM Pt. 850, App. A Appendix A to Part 850—Chronic Beryllium Disease Prevention Program Informed...

10 CFR Appendix A to Part 850 - Chronic Beryllium Disease Prevention Program Informed Consent Form

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 4 2012-01-01 2012-01-01 false Chronic Beryllium Disease Prevention Program Informed Consent Form A Appendix A to Part 850 Energy DEPARTMENT OF ENERGY CHRONIC BERYLLIUM DISEASE PREVENTION PROGRAM Pt. 850, App. A Appendix A to Part 850—Chronic Beryllium Disease Prevention Program Informed...

10 CFR Appendix A to Part 850 - Chronic Beryllium Disease Prevention Program Informed Consent Form

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 4 2014-01-01 2014-01-01 false Chronic Beryllium Disease Prevention Program Informed Consent Form A Appendix A to Part 850 Energy DEPARTMENT OF ENERGY CHRONIC BERYLLIUM DISEASE PREVENTION PROGRAM Pt. 850, App. A Appendix A to Part 850—Chronic Beryllium Disease Prevention Program Informed...

Measuring soil moisture near soil surface...minor differences due to neutron source type

Treesearch

Robert R. Ziemer; Irving Goldberg; Norman A. MacGillivray

1967-01-01

Moisture measurements were made in three media?paraffin, water, saturated sand?with four neutron miusture meters, each containing 226-radium-beryllium, 227-actinium-beryllium, 238-plutonium-beryllium, or 241-americium-beryllium neutron sources. Variability in surface detection by the different sources may be due to differences in neutron sources, in length of source,...

Measuring soil moisture near soil surface ... minor differences due to neutron source type

Treesearch

Robert R. Ziemer; Irving Goldberg; Norman A. MacGillivray

1967-01-01

Abstract - Moisture measurements were made in three media--paraffin, water, saturated sand--with four neutron moisture meters, each containing 226-radium-beryllium, 227-actinium-beryllium, 239-plutonium-beryllium, or 241-americium-beryllium neutron sources. Variability in surface detection by the different sources may be due to differences in neutron sources, in...

Method for fabricating beryllium structures

DOEpatents

Hovis, Jr., Victor M.; Northcutt, Jr., Walter G.

1977-01-01

Thin-walled beryllium structures are prepared by plasma spraying a mixture of beryllium powder and about 2500 to 4000 ppm silicon powder onto a suitable substrate, removing the plasma-sprayed body from the substrate and placing it in a sizing die having a coefficient of thermal expansion similar to that of the beryllium, exposing the plasma-sprayed body to a moist atmosphere, outgassing the plasma-sprayed body, and then sintering the plasma-sprayed body in an inert atmosphere to form a dense, low-porosity beryllium structure of the desired thin-wall configuration. The addition of the silicon and the exposure of the plasma-sprayed body to the moist atmosphere greatly facilitate the preparation of the beryllium structure while minimizing the heretofore deleterious problems due to grain growth and grain orientation.

Method for fabricating beryllium-based multilayer structures

DOEpatents

Skulina, Kenneth M.; Bionta, Richard M.; Makowiecki, Daniel M.; Alford, Craig S.

2003-02-18

Beryllium-based multilayer structures and a process for fabricating beryllium-based multilayer mirrors, useful in the wavelength region greater than the beryllium K-edge (111 .ANG. or 11.1 nm). The process includes alternating sputter deposition of beryllium and a metal, typically from the fifth row of the periodic table, such as niobium (Nb), molybdenum (Mo), ruthenium (Ru), and rhodium (Rh). The process includes not only the method of sputtering the materials, but the industrial hygiene controls for safe handling of beryllium. The mirrors made in accordance with the process may be utilized in soft x-ray and extreme-ultraviolet projection lithography, which requires mirrors of high reflectivity (>60%) for x-rays in the range of 60-140 .ANG. (60-14.0 nm).

Copper uptake by the water hyacinth. [Eichornia crassipes

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

Lee, T.A.; Hardy, J.K.

1987-01-01

Factors affecting Cu/sup +2/ uptake by the water hyacinth (Eichornia crassipes) were examined. Two phases of copper uptake were observed throughout the uptake range (1-1000 mg/1). An initial rapid uptake phase of 4 hours followed by a slower, near linear uptake phase extending past 48 hours was observed. Stirring the solution enhanced uptake, suggesting copper removal is partially diffusion limited. Variations in pH over the range of 3 to 10 did not significantly affect uptake. Increasing the root mass of the plant increased the amount of copper taken up. As solution volume was increased more copper was removed. The presencemore » of complexing agents during the uptake phase reduced copper uptake. The inability of complexing agents to recover all copper initially removed by a plant suggests a migration to sites within the plant.« less

Instellar Gas Experiment (IGE): Testing interstellar gas particles to provide information on the processes of nucleosynthesis in the big bang stars and supernova

NASA Technical Reports Server (NTRS)

Lind, Don

1985-01-01

The Interstellar Gas Experiment (IGE) is designed to collect particles of the interstellar gas - a wind of interstellar media particles moving in the vicinity of the solar system. These particles will be returned to earth where the isotopic ratios of the noble gases among these particles will be measured. IGE was designed and programmed to expose 7 sets of six copper-beryllium metallic collecting foils to the flux of neutral interstellar gas particles which penetrate the heliosphere to the vicinity of the earth's orbit. These particles are trapped in the collecting foils and will be returned to earth for mass-spectrographic analysis when Long Duration Exposure Facility (LDEF) on which IGE was launched, is recovered.

Confined ion energy >200 keV and increased fusion yield in a DPF with monolithic tungsten electrodes and pre-ionization

NASA Astrophysics Data System (ADS)

Lerner, Eric J.; Hassan, Syed M.; Karamitsos, Ivana; Von Roessel, Fred

2017-10-01

To reduce impurities in the dense plasma focus FF-1 device, we used monolithic tungsten electrodes with pre-ionization. With this new set-up, we demonstrated a three-fold reduction of impurities by mass and a ten-fold reduction by ion number. FF-1 produced a 50% increase in fusion yield over our previous copper electrodes, both for a single shot and for a mean of ten consecutive shots with the same conditions. These results represent a doubling of fusion yield as compared with any other plasma focus device with the same 60 kJ energy input. In addition, FF-1 produced a new single-shot record of 240 ± 20 keV for mean ion energy, a record for any confined fusion plasma, using any device, and a 50% improvement in ten-shot mean ion energy. With a deuterium-nitrogen mix and corona-discharge pre-ionization, we were also able to reduce the standard deviation in the fusion yield to about 15%, a four-fold reduction over the copper-electrode results. We intend to further reduce impurities with new experiments using microwave treatment of tungsten electrodes, followed by the use of beryllium electrodes.

High thermal expansion, sealing glass

DOEpatents

Brow, Richard K.; Kovacic, Larry

1993-01-01

A glass composition for hermetically sealing to high thermal expansion materials such as aluminum alloys, stainless steels, copper, and copper/beryllium alloys, which includes between about 10 and about 25 mole percent Na.sub.2 O, between about 10 and about 25 mole percent K.sub.2 O, between about 5 and about 15 mole percent Al.sub.2 O.sub.3, between about 35 and about 50 mole percent P.sub.2 O.sub.5 and between about 5 and about 15 mole percent of one of PbO, BaO, and mixtures thereof. The composition, which may also include between 0 and about 5 mole percent Fe.sub.2 O.sub.3 and between 0 and about 10 mole percent B.sub.2 O.sub.3, has a thermal expansion coefficient in a range of between about 160 and 210.times.10-7/.degree.C. and a dissolution rate in a range of between about 2.times.10.sup.- 7 and 2.times.10.sup.-9 g/cm.sup.2 -min. This composition is suitable to hermetically seal to metallic electrical components which will be subjected to humid environments over an extended period of time.

High thermal expansion, sealing glass

DOEpatents

Brow, R.K.; Kovacic, L.

1993-11-16

A glass composition is described for hermetically sealing to high thermal expansion materials such as aluminum alloys, stainless steels, copper, and copper/beryllium alloys, which includes between about 10 and about 25 mole percent Na[sub 2]O, between about 10 and about 25 mole percent K[sub 2]O, between about 5 and about 15 mole percent Al[sub 2]O[sub 3], between about 35 and about 50 mole percent P[sub 2]O[sub 5] and between about 5 and about 15 mole percent of one of PbO, BaO, and mixtures thereof. The composition, which may also include between 0 and about 5 mole percent Fe[sub 2]O[sub 3] and between 0 and about 10 mole percent B[sub 2]O[sub 3], has a thermal expansion coefficient in a range of between about 160 and 210[times]10[sup [minus]7]/C and a dissolution rate in a range of between about 2[times]10[sup [minus]7] and 2[times]10[sup [minus]9]g/cm[sup 2]-min. This composition is suitable to hermetically seal to metallic electrical components which will be subjected to humid environments over an extended period of time.

Infertility and growth suppression in beef cattle associated with abnormalities in their geochemical environment

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

Case, A.A.; Selby, L.A.; Hutcheson, D.P.

1973-01-01

Infertility and growth suppression were reported in two beef-cattle herds located in a small valley in central Missouri. Clinical, epidemiological, and toxicological evaluation of the herds and ranches by personnel from the Environmental Health Surveillance Center suggested that the problem was related to the local geochemical environment. US Geological Survey personnel, engaged in a geochemical survey of the natural environment of Missouri, were asked to evaluate the site geochemically. Geochemical studies of waters, alluvial deposits, and vegetation revealed that aluminum, beryllium, cobalt, copper, molybdenum, and nickel occur in anomalous concentrations in these materials. The principal source of these elements ismore » believed to be clay, shale, limestone, coal, and pyrite that were exposed at the head of the valley when the clay was mined. Young beef cattle from two ranches which were pastured on the flood plain below the claypile experienced a severe growth suppression from an imbalance of minerals or other nutrients in their feed or water, or both. Metabolic disturbances in these cattle resembled chronic molybdenosis. Imbalances of copper and molybdenum, in addition to those of cobalt and other substances, may have contributed to this syndrome. 17 references.« less

Sampling and Analysis Issues Relating to the ACGIH Notice of Intended Change for the Beryllium Threshold Limit Value

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

Brisson, Michael J.; Ashley, Kevin

2005-08-16

Beryllium in various forms is widely used throughout the world in ceramics, aerospace and military applications, electronics, and sports equipment. Workplace exposure to beryllium is a growing industrial hygiene concern due to the potential for development of chronic beryllium disease (CBD), a lung condition with no known cure, in a small percentage of those exposed. There are workplace exposure limits for beryllium that have been in place for several decades. However, recent studies suggest that the current American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV) and the Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL)more » may not be sufficiently protective for workers who are potentially exposed to airborne beryllium. Early in 2005, ACGIH issued a Notice of Intended Change (NIC) to the current TLV for beryllium which entails a 100-fold reduction (from 2 to 0.02 micrograms per cubic meter of sampled air). It is noted that ACGIH TLVs do not carry legal force in the manner that OSHA PELs or other federal regulations do. Nevertheless, OSHA plans a beryllium rulemaking in the near future, and a reduction in the PEL is anticipated. Also, if this change in the TLV for beryllium is adopted, it is reasonable to assume that at least some sampling and analysis activities will need to be modified to address airborne beryllium at the lower levels. There are implications to both the industrial hygiene and the laboratory communities, which are discussed.« less

Beryllium—A critical mineral commodity—Resources, production, and supply chain

USGS Publications Warehouse

Lederer, Graham W.; Foley, Nora K.; Jaskula, Brian W.; Ayuso, Robert A.

2016-11-14

Beryllium is a lightweight metallic element used in a wide variety of specialty and industrial applications. As a function of its unique chemical and physical properties, such as a high stiffness-to-weight ratio, resistance to temperature extremes, and high thermal conductivity, beryllium cannot be easily replaced by substitute materials in applications where combinations of these properties make it the material of choice. Because the number of beryllium producers is limited and the use of substitute materials in specific defense-related applications that are vital to national security is inadequate, several studies have categorized beryllium as a critical and strategic material. This categorization has led to the United States Government recommending that beryllium be stockpiled for use in the event of a national emergency. As of December 31, 2015, the National Defense Stockpile inventory of hot-pressed beryllium metal powder, structured beryllium metal powder, and vacuum-cast beryllium metal totaled 78 metric tons (t).The U.S. Geological Survey (USGS) Mineral Resources Program supports research on the occurrence, quality, quantity, and availability of mineral resources vital to the economy and national security. The USGS, through its National Minerals Information Center (NMIC), collects, analyzes, and disseminates information on more than 90 nonfuel mineral commodities from more than 180 countries. This fact sheet provides information on the production, consumption, supply chain, geology, and resource availability of beryllium in a global context.

Inhibited solid propellant composition containing beryllium hydride

NASA Technical Reports Server (NTRS)

Thompson, W. W. (Inventor)

1978-01-01

An object of this invention is to provide a composition of beryllium hydride and carboxy-terminated polybutadiene which is stable. Another object of this invention is to provide a method for inhibiting the reactivity of beryllium hydride toward carboxy-terminated polybutadiene. It was found that a small amount of lecithin inhibits the reaction of beryllium hydride with the acid groups in carboxy terminated polybutadiene.

Beryllium for fusion application - recent results

NASA Astrophysics Data System (ADS)

Khomutov, A.; Barabash, V.; Chakin, V.; Chernov, V.; Davydov, D.; Gorokhov, V.; Kawamura, H.; Kolbasov, B.; Kupriyanov, I.; Longhurst, G.; Scaffidi-Argentina, F.; Shestakov, V.

2002-12-01

The main issues for the application of beryllium in fusion reactors are analyzed taking into account the latest results since the ICFRM-9 (Colorado, USA, October 1999) and presented at 5th IEA Be Workshop (10-12 October 2001, Moscow Russia). Considerable progress has been made recently in understanding the problems connected with the selection of the beryllium grades for different applications, characterization of the beryllium at relevant operational conditions (irradiation effects, thermal fatigue, etc.), and development of required manufacturing technologies. The key remaining problems related to the application of beryllium as an armour in near-term fusion reactors (e.g. ITER) are discussed. The features of the application of beryllium and beryllides as a neutron multiplier in the breeder blanket for power reactors (e.g. DEMO) in pebble-bed form are described.

Airborne copper exposure in school environments associated with poorer motor performance and altered basal ganglia.

PubMed

Pujol, Jesus; Fenoll, Raquel; Macià, Dídac; Martínez-Vilavella, Gerard; Alvarez-Pedrerol, Mar; Rivas, Ioar; Forns, Joan; Deus, Joan; Blanco-Hinojo, Laura; Querol, Xavier; Sunyer, Jordi

2016-06-01

Children are more vulnerable to the effects of environmental elements. A variety of air pollutants are among the identified factors causing neural damage at toxic concentrations. It is not obvious, however, to what extent the tolerated high levels of air pollutants are able to alter brain development. We have specifically investigated the neurotoxic effects of airborne copper exposure in school environments. Speed and consistency of motor response were assessed in 2836 children aged from 8 to 12 years. Anatomical MRI, diffusion tensor imaging, and functional MRI were used to directly test the brain repercussions in a subgroup of 263 children. Higher copper exposure was associated with poorer motor performance and altered structure of the basal ganglia. Specifically, the architecture of the caudate nucleus region was less complete in terms of both tissue composition and neural track water diffusion. Functional MRI consistently showed a reciprocal connectivity reduction between the caudate nucleus and the frontal cortex. The results establish an association between environmental copper exposure in children and alterations of basal ganglia structure and function.

Fiber Laser Welding-Brazing Characteristics of Dissimilar Metals AZ31B Mg Alloys to Copper with Mg-Based Filler

NASA Astrophysics Data System (ADS)

Zhao, Xiaoye; Tan, Caiwang; Meng, Shenghao; Chen, Bo; Song, Xiaoguo; Li, Liqun; Feng, Jicai

2018-03-01

Fiber laser welding-brazing of 1-mm-thick AZ31B Mg alloys to 1.5-mm-thick copper (T2) with Mg-based filler was performed in a lap configuration. The weld appearance, interfacial microstructure and mechanical properties were investigated with different heat inputs. The results indicated that processing windows for optimizing appropriate welding parameters were relatively narrow in this case. Visually acceptable joints with certain strength were achieved at appropriate welding parameters. The maximum tensile-shear fracture load of laser-welded-brazed Mg/Cu joint could reach 1730 N at the laser power of 1200 W, representing 64.1% joint efficiency relative to AZ31Mg base metal. The eutectic structure (α-Mg + Mg2Cu) and Mg-Cu intermetallic compound was observed at the Mg/Cu interface, and Mg-Al-Cu ternary intermetallic compound were identified between intermetallics and eutectic structure at high heat input. All the joints fractured at the Mg-Cu interface. However, the fracture mode was found to differ. For laser power of 1200 W, the surface was characterized by tearing edge, while that with poor joint strength was almost dominated by smooth surface or flat tear pattern.

Quantification of joint inflammation in rheumatoid arthritis by time-resolved diffuse optical spectroscopy and tracer kinetic modeling

NASA Astrophysics Data System (ADS)

Ioussoufovitch, Seva; Morrison, Laura B.; Lee, Ting-Yim; St. Lawrence, Keith; Diop, Mamadou

2015-03-01

Rheumatoid arthritis (RA) is characterized by chronic synovial inflammation, which can cause progressive joint damage and disability. Diffuse optical spectroscopy (DOS) and imaging have the potential to become potent monitoring tools for RA. We devised a method that combined time-resolved DOS and tracer kinetics modeling to rapidly and reliably quantify blood flow in the joint. Preliminary results obtained from two animals show that the technique can detect joint inflammation as early as 5 days after onset.

Beryllium Metal Supply Options

DTIC Science & Technology

1989-01-01

vacuum evaporator treatment to form ABF crystals, which are separated in a horizontal bowl centrifuge and dried. Formation of Beryllium Fluoride The...addition, the high viscosity of the slag may cause poor pebble formation and yield. Thus, the following programs to improve efficiency have been suggested...and avoiding the formation of beryllium fines, which are difficult to recover. The production of a readily manageable beryllium sponge is desired, which

Diffusion welding of MA 6000 and a conventional nickel-base superalloy

NASA Technical Reports Server (NTRS)

Moore, T. J.; Glasgow, T. K.

1985-01-01

A feasibility study of diffusion welding the oxide dispersion strengthened (ODS) alloy MA 6000 to itself and to conventional Ni-base superalloy Udimet 700 was conducted. Butt joints between MA 6000 pieces and lap joints between Udimet 700 and the ODS alloy were produced by hot pressing for 1.25 hr at temperatures ranging from 1000 to 1200 C (1832-2192 F) in vacuum. Following pressing, all weldments were heat treated and machined into mechanical property test specimens. While three different combinations of recrystallized and unrecrystallized MA 6000 butt joints were produced, the unrecrystallized to unrecrystallized joint was most successful as determined by mechanical properties and microstructural examination. Failure to weld the recrystallized material probably related to a lack of adequate deformation at the weld interface. While recrystallized MA 6000 could be diffusion welded to Udimet 700 in places, complete welding over the entire lap joint was not achieved, again due to the lack of sufficient deformation at the faying surfaces. Several methods are proposed to promote the intimate contact necessary for diffusion welding MA 6000 to itself and to superalloys.

Cost effective aluminum beryllium mirrors for critical optics applications

NASA Astrophysics Data System (ADS)

Say, Carissa; Duich, Jack; Huskamp, Chris; White, Ray

2013-09-01

The unique performance of aluminum-beryllium frequently makes it an ideal material for manufacturing precision optical-grade metal mirrors. Traditional methods of manufacture utilize hot-pressed powder block in billet form which is subsequently machined to final dimensions. Complex component geometries such as lightweighted, non-plano mirrors require extensive tool path programming, fixturing, and CNC machining time and result in a high buy-to-fly ratio (the ratio of the mass of raw material purchased to the mass of the finished part). This increases the cost of the mirror structure as a significant percentage of the procurement cost is consumed in the form of machining, tooling, and scrap material that do not add value to the final part. Inrad Optics, Inc. and IBC Advanced Alloys Corp. undertook a joint study to evaluate the suitability of investment-cast Beralcast® 191 and 363 aluminum-beryllium as a precision mirror substrate material. Net shape investment castings of the desired geometry minimizes machining to just cleanup stock, thereby reducing the recurring procurement cost while still maintaining performance. The thermal stability of two mirrors, (one each of Beralcast® 191 and Beralcast® 363), was characterized from -40°F to +150°F. A representative pocketed mirror was developed, including the creation of a relevant geometry and production of a cast component to validate the approach. Information from the demonstration unit was used as a basis for a comparative cost study of the representative mirror produced in Beralcast® and one machined from a billet of AlBeMet® 162 (AlBeMet® is a registered trademark of Materion Corporation). The technical and financial results of these studies will be discussed in detail.

Development of a new passive sampler based on diffusive milligel beads for copper analysis in water.

PubMed

Perez, M; Reynaud, S; Lespes, G; Potin-Gautier, M; Mignard, E; Chéry, P; Schaumlöffel, D; Grassl, B

2015-08-26

A new passive sampler was designed and characterized for the determination of free copper ion (Cu(2+)) concentration in aqueous solution. Each sampling device was composed of a set of about 30 diffusive milligel (DMG) beads. Milligel beads with incorporated cation exchange resin (Chelex) particles were synthetized using an adapted droplet-based millifluidic process. Beads were assumed to be prolate spheroids, with a diameter of 1.6 mm and an anisotropic factor of 1.4. The milligel was controlled in chemical composition of hydrogel (monomer, cross-linker, initiator and Chelex concentration) and characterized in pore size. Two types of sampling devices were developed containing 7.5% and 15% of Chelex, respectively, and 6 nm pore size. The kinetic curves obtained demonstrated the accumulation of copper in the DMG according to the process described in the literature as absorption (and/or adsorption) and release following the Fick's first law of diffusion. For their use in water monitoring, the typical physico-chemical characteristics of the samplers, i.e. the mass-transfer coefficient (k0) and the sampler-water partition coefficient (Ksw), were determined based on a static exposure design. In order to determine the copper concentration in the samplers after their exposure, a method using DMG bead digestion combined to Inductively Coupled Plasma - Atomic Emission Spectrometry (ICP-AES) analysis was developed and optimized. The DMG devices proved to be capable to absorb free copper ions from an aqueous solution, which could be accurately quantified with a mean recovery of 99% and a repeatability of 7% (mean relative uncertainty). Copyright © 2015 Elsevier B.V. All rights reserved.

Isotopic Transmutations in Irradiated Beryllium and Their Implications on MARIA Reactor Operation

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

Andrzejewski, Krzysztof J.; Kulikowska, Teresa A

2004-04-15

Beryllium irradiated by neutrons with energies above 0.7 MeV undergoes (n,{alpha}) and (n,2n) reactions. The Be(n,{alpha}) reaction results in subsequent buildup of {sup 6}Li and {sup 3}He isotopes with large thermal neutron absorption cross sections causing poisoning of irradiated beryllium. The amount of the poison isotopes depends on the neutron flux level and spectrum. The high-flux MARIA reactor operated in Poland since 1975 consists of a beryllium matrix with fuel channels in cutouts of beryllium blocks. As the experimental determination of {sup 6}Li, {sup 3}H, and {sup 3}He content in the operational reactor is impossible, a systematic computational study ofmore » the effect of {sup 3}He and {sup 6}Li presence in beryllium blocks on MARIA reactor reactivity and power density distribution has been undertaken. The analysis of equations governing the transmutation has been done for neutron flux parameters typical for MARIA beryllium blocks. Study of the mutual influence of reactor operational parameters and the buildup of {sup 6}Li, {sup 3}H, and {sup 3}He in beryllium blocks has shown the necessity of a detailed spatial solution of transmutation equations in the reactor, taking into account the whole history of its operation. Therefore, fuel management calculations using the REBUS code with included chains for Be(n,{alpha})-initiated reactions have been done for the whole reactor lifetime. The calculated poisoning of beryllium blocks has been verified against the critical experiment of 1993. Finally, the current {sup 6}Li, {sup 3}H, and {sup 3}He contents, averaged for each beryllium block, have been calculated. The reactivity drop caused by this poisoning is {approx}7%.« less

Exposure and genetics increase risk of beryllium sensitisation and chronic beryllium disease in the nuclear weapons industry.

PubMed

Van Dyke, Michael V; Martyny, John W; Mroz, Margaret M; Silveira, Lori J; Strand, Matt; Cragle, Donna L; Tankersley, William G; Wells, Susan M; Newman, Lee S; Maier, Lisa A

2011-11-01

Beryllium sensitisation (BeS) and chronic beryllium disease (CBD) are caused by exposure to beryllium with susceptibility affected by at least one well-studied genetic host factor, a glutamic acid residue at position 69 (E69) of the HLA-DPβ chain (DPβE69). However, the nature of the relationship between exposure and carriage of the DPβE69 genotype has not been well studied. The goal of this study was to determine the relationship between DPβE69 and exposure in BeS and CBD. Current and former workers (n=181) from a US nuclear weapons production facility, the Y-12 National Security Complex (Oak Ridge, Tennessee, USA), were enrolled in a case-control study including 35 individuals with BeS and 19 with CBD. HLA-DPB1 genotypes were determined by PCR-SSP. Beryllium exposures were assessed through worker interviews and industrial hygiene assessment of work tasks. After removing the confounding effect of potential beryllium exposure at another facility, multivariate models showed a sixfold (OR 6.06, 95% CI 1.96 to 18.7) increased odds for BeS and CBD combined among DPβE69 carriers and a fourfold (OR 3.98, 95% CI 1.43 to 11.0) increased odds for those exposed over an assigned lifetime-weighted average exposure of 0.1 μg/m(3). Those with both risk factors had higher increased odds (OR 24.1, 95% CI 4.77 to 122). DPβE69 carriage and high exposure to beryllium appear to contribute individually to the development of BeS and CBD. Among workers at a beryllium-using facility, the magnitude of risk associated with either elevated beryllium exposure or carriage of DPβE69 alone appears to be similar.

Mineral resources of Elko County, Nevada

USGS Publications Warehouse

Smith, Roscoe Maurice

1976-01-01

Of the 66 named mining districts in Elko County, 56 have been productive of one or more of 19 different commodities: 11 metals--copper, gold, silver, lead, zinc, mercury, tungsten, manganese, iron, uranium, and antimony; 8 nonmetals--sand and gravel, stone, barite, diatomite, gems, oil shale, volcanic ash, and clay. In addition to the commodities produced, at least 5 others--beryllium, molybdenum, tin, phosphorite, and petroleum, occur in amounts sufficient to warrant exploration. The other districts have been explored, but no production has been recorded. Total value-when-sold of production recorded through 1969 was nearly $91 million; actual production was considerably greater, especially if sand and gravel, barite, and other nonmetallic products before 1953 are included. In value of metals produced, the five highest districts are Mountain City ($26 million), Tuscarora ($11 million), Jarbidge ($10 million), Aura ($6 million), and Railroad (nearly $5 million). The Rio Tinto copper mine in the Mountain City district yielded $21 million. Of the 17 districts that produced nonmetallic minerals, Bootstrap .is the largest producer, containing the Rossi mine, one of the two largest barite mines in the United States. Most of /he metals produced name from veins and replacement deposits in limestone or dolomite near granitic stocks; exceptions are manganese and mercury, which are not associated with known or inferred stocks; mercury is further excepted because it occurs in volcanic rocks, as do a few deposits of the major metals. The largest deposit--the Rio Tinto lode--was a combination of fissure filling and replacement along a bedding plane shear zone 150 ft wide and 1,200 ft long in carbonaceous shale of the Valmy Formation; this deposit is apparently older than the Mountain City stock and its mineralization may be related to Paleozoic mafic volcanism later than a major thrust fault, inferred to underlie the area at a depth of about 5,000 ft. Most of the nonmetallic minerals mined were sedimentary bedded deposits, but mica was mined from pegmatite deposits, and turquoise from both placer and hydrothermal deposits. The largest known reserves of metals (1973) are of porphyry copper in the Dolly Varden district and gold in the Bootstrap district. Reserves of barite also are presumed to be large. The greatest potential for future production of metals, notably copper and gold, appears to be in the known districts or extensions of them and peripheral to deposits that are related to known or concealed plutons and thrust faults. Potential resources in deposits too low in grade to be worked profitably at the present time include all commodities that have been produced and, in addition, known, deposits of beryllium, molybdenum, tin, and phosphorite. Speculative resources in undiscovered deposits may reasonably be predicted to include all known commodities as well as others that are unsuspected. Petroleum may yet be produced from the Elko Formation and geothermal energy from the Ruby Valley and Elko areas.

Sodium enhances indium-gallium interdiffusion in copper indium gallium diselenide photovoltaic absorbers.

PubMed

Colombara, Diego; Werner, Florian; Schwarz, Torsten; Cañero Infante, Ingrid; Fleming, Yves; Valle, Nathalie; Spindler, Conrad; Vacchieri, Erica; Rey, Germain; Guennou, Mael; Bouttemy, Muriel; Manjón, Alba Garzón; Peral Alonso, Inmaculada; Melchiorre, Michele; El Adib, Brahime; Gault, Baptiste; Raabe, Dierk; Dale, Phillip J; Siebentritt, Susanne

2018-02-26

Copper indium gallium diselenide-based technology provides the most efficient solar energy conversion among all thin-film photovoltaic devices. This is possible due to engineered gallium depth gradients and alkali extrinsic doping. Sodium is well known to impede interdiffusion of indium and gallium in polycrystalline Cu(In,Ga)Se 2 films, thus influencing the gallium depth distribution. Here, however, sodium is shown to have the opposite effect in monocrystalline gallium-free CuInSe 2 grown on GaAs substrates. Gallium in-diffusion from the substrates is enhanced when sodium is incorporated into the film, leading to Cu(In,Ga)Se 2 and Cu(In,Ga) 3 Se 5 phase formation. These results show that sodium does not decrease per se indium and gallium interdiffusion. Instead, it is suggested that sodium promotes indium and gallium intragrain diffusion, while it hinders intergrain diffusion by segregating at grain boundaries. The deeper understanding of dopant-mediated atomic diffusion mechanisms should lead to more effective chemical and electrical passivation strategies, and more efficient solar cells.

Stabilization of Oxidized Copper Nanoclusters in Confined Spaces

DOE PAGES

Akter, Nusnin; Wang, Mengen; Zhong, Jian-Qiang; ...

2018-01-04

Copper is an important industrial catalyst. The ability to manipulate the oxidation state of copper clusters in a controlled way is critical to understanding structure–reactivity relations of copper catalysts at the molecular level. Experimentally, cupric oxide surfaces or even small domains can only be stabilized at elevated temperatures and in the presence of oxygen, as copper can be easily reduced under reaction conditions. Herein bilayer silica films grown on a metallic substrate are used to trap diluted copper oxide clusters. By combining in situ experiments with first principles calculations, it is found that the confined space created by the silicamore » film leads to an increase in the energy barrier for Cu diffusion. Dispersed copper atoms trapped by the silica film can be easily oxidized by surface oxygen chemisorbed on the metallic substrate, which results in the formation and stabilization of Cu 2+ cations.« less

Vacuum Brazing of Accelerator Components

NASA Astrophysics Data System (ADS)

Singh, Rajvir; Pant, K. K.; Lal, Shankar; Yadav, D. P.; Garg, S. R.; Raghuvanshi, V. K.; Mundra, G.

2012-11-01

Commonly used materials for accelerator components are those which are vacuum compatible and thermally conductive. Stainless steel, aluminum and copper are common among them. Stainless steel is a poor heat conductor and not very common in use where good thermal conductivity is required. Aluminum and copper and their alloys meet the above requirements and are frequently used for the above purpose. The accelerator components made of aluminum and its alloys using welding process have become a common practice now a days. It is mandatory to use copper and its other grades in RF devices required for accelerators. Beam line and Front End components of the accelerators are fabricated from stainless steel and OFHC copper. Fabrication of components made of copper using welding process is very difficult and in most of the cases it is impossible. Fabrication and joining in such cases is possible using brazing process especially under vacuum and inert gas atmosphere. Several accelerator components have been vacuum brazed for Indus projects at Raja Ramanna Centre for Advanced Technology (RRCAT), Indore using vacuum brazing facility available at RRCAT, Indore. This paper presents details regarding development of the above mentioned high value and strategic components/assemblies. It will include basics required for vacuum brazing, details of vacuum brazing facility, joint design, fixturing of the jobs, selection of filler alloys, optimization of brazing parameters so as to obtain high quality brazed joints, brief description of vacuum brazed accelerator components etc.

24 CFR 3280.605 - Joints and connections.

Code of Federal Regulations, 2013 CFR

2013-04-01

... of the fitting. Plastic pipe and copper tubing shall be inserted to the full depth of the solder cup..., cutting oil and foreign matter shall be removed. Pipe joint cement or thread lubricant shall be of... connected to a public water system, made with solder having not more than 0.2 percent lead. (4) Plastic pipe...

24 CFR 3280.605 - Joints and connections.

Code of Federal Regulations, 2012 CFR

2012-04-01

... of the fitting. Plastic pipe and copper tubing shall be inserted to the full depth of the solder cup..., cutting oil and foreign matter shall be removed. Pipe joint cement or thread lubricant shall be of... connected to a public water system, made with solder having not more than 0.2 percent lead. (4) Plastic pipe...

24 CFR 3280.605 - Joints and connections.

Code of Federal Regulations, 2011 CFR

2011-04-01

... of the fitting. Plastic pipe and copper tubing shall be inserted to the full depth of the solder cup... connected to a public water system, made with solder having not more than 0.2 percent lead. (4) Plastic pipe, fittings and joints. Plastic pipe and fittings shall be joined by installation methods recommended by the...

Controlling molecular condensation/diffusion of copper phthalocyanine by local electric field induced with scanning tunneling microscope tip

NASA Astrophysics Data System (ADS)

Nagaoka, Katsumi; Yaginuma, Shin; Nakayama, Tomonobu

2018-02-01

We have discovered the condensation/diffusion phenomena of copper phthalocyanine (CuPc) molecules controlled with a pulsed electric field induced by the scanning tunneling microscope tip. This behavior is not explained by the conventional induced dipole model. In order to understand the mechanism, we have measured the electronic structure of the molecule by tunneling spectroscopy and also performed theoretical calculations on molecular orbitals. These data clearly indicate that the molecule is positively charged owing to charge transfer to the substrate, and that hydrogen bonding exists between CuPc molecules, which makes the molecular island stable.

An electrolytic process for ultra fine beryllium

NASA Technical Reports Server (NTRS)

Lidman, W. G.; Griffiths, V.

1972-01-01

Studies were made on the electrolysis of a molten BeCl2-NaCl bath using a mercury cathode and beryllium anode. A quasi-amalgam was obtained. The beryllium was consolidated by direct hot pressing of the amalgam at temperatures in the range of 800 C and using pressures of 5,000, 10,000 and 20,000 psi. The work confirms the ability to produce ultrafine beryllium particles by electrolysis.

Brazing of beryllium for structural applications

NASA Technical Reports Server (NTRS)

Vogan, J. W.

1972-01-01

Progress made in fabricating a beryllium compression tube structure and a stiffened beryllium panel. The compression tube was 7.6cm in diameter and 30.5cm long with titanium end fittings. The panel was 203cm long and stiffened with longitudinal stringers. Both units were assembled by brazing with BAg-18 braze alloy. The detail parts were fabricated by hot forming 0.305cm beryllium sheet and the brazing parameters established.

Sampling and analysis plan for assessment of beryllium in soils surrounding TA-40 building 15

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

Ruedig, Elizabeth

Technical Area (TA) 40 Building 15 (40-15) is an active firing site at Los Alamos National Laboratory. The weapons facility operations (WFO) group plans to build an enclosure over the site in 2017, so that test shots may be conducted year-round. The enclosure project is described in PRID 16P-0209. 40-15 is listed on LANL OSH-ISH’s beryllium inventory, which reflects the potential for beryllium in/on soils and building surfaces at 40-15. Some areas in and around 40-15 have previously been sampled for beryllium, but past sampling efforts did not achieve complete spatial coverage of the area. This Sampling and Analysis Planmore » (SAP) investigates the area surrounding 40-15 via 9 deep (≥1-ft.) soil samples and 11 shallow (6-in.) soil samples. These samples will fill the spatial data gaps for beryllium at 40-15, and will be used to support OSH-ISH’s final determination of 40-15’s beryllium registry status. This SAP has been prepared by the Environmental Health Physics program in consultation with the Industrial Hygiene program. Industrial Hygiene is the owner of LANL’s beryllium program, and will make a final determination with regard to the regulatory status of beryllium at 40-15.« less

Microstructure of arc brazed and diffusion bonded joints of stainless steel and SiC reinforced aluminum matrix composite

NASA Astrophysics Data System (ADS)

Elßner, M.; Weis, S.; Grund, T.; Wagner, G.; Habisch, S.; Mayr, P.

2016-03-01

Joint interfaces of aluminum and stainless steel often exhibit intermetallics of Al-Fe, which limit the joint strength. In order to reduce these brittle phases in joints of aluminum matrix composites (AMC) and stainless steel, diffusion bonding and arc brazing are used. Due to the absence of a liquid phase, diffusion welding can reduce the formation of these critical in- termetallics. For this joining technique, the influence of surface treatments and adjusted time- temperature-surface-pressure-regimes is investigated. On the other hand, arc brazing offers the advantage to combine a localized heat input with the application of a low melting filler and was conducted using the system Al-Ag-Cu. Results of the joining tests using both approaches are described and discussed with regard to the microstructure of the joints and the interfaces.

Reaction layer characterization of the braze joint of silicon nitride to stainless steel

NASA Astrophysics Data System (ADS)

Xu, R.; Indacochea, J. E.

1994-10-01

This investigation studies the role of titanium in the development of the reaction layer in braze joining silicon nitride to stainless steel using titanium-active copper-silver filler metals. This reaction layer formed as a result of titanium diffusing to the filler metal/silicon nitride interface and reacting with the silicon nitride to form the intermetallics, titanium nitride (TiN) and titanium suicide (Ti 5Si3). This reaction layer, as recognized in the literature, allows wetting of the ceramic substrate by the molten filler metal. The reaction layer thickness increases with temperature and time. Its growth rate obeys the parabolic relationship. Activation energies of 220.1 and 210.9 kj/mol were calculated for growth of the reaction layer for the two filler metals used. These values are close to the activation energy of nitrogen in TiN (217.6 kj/mol). Two filler metals were used in this study, Ticusil (68.8 wt% Ag, 26.7 wt% Cu, 4.5 wt% Ti) and CB4 (70.5 wt% Ag, 26.5 wt% Cu, 3.0 wt% Ti). The joints were processed in vacuum at temperatures of 840 to 900 °C at various times. Bonding strength is affected by reaction layer thickness in the absence of Ti-Cu intermetallics in the filler metal matrix.

IRIS TOXICOLOGICAL REVIEW AND SUMMARY ...

EPA Pesticide Factsheets

EPA's assessment of the noncancer health effects and carcinogenic potential of Beryllium was added to the IRIS database in 1998. The IRIS program is updating the IRIS assessment for Beryllium. This update will incorporate health effects information published since the last assessment was prepared as well as new risk assessment methods. The IRIS assessment for Beryllium will consist of an updated Toxicological Review and IRIS Summary. The Toxicological Review is a critical review of the physicochemical and toxicokinetic properties of the chemical and its toxicity in humans and experimental systems. The assessment will present reference values for noncancer effects of Beryllium (RfD and RfC) and a cancer assessment. The Toxicological Review and IRIS Summary will be subject to internal peer consultation, Agency and Interagency review, and external scientific peer review. The final products will constitute the Agency's opinion on the toxicity of Beryllium. Beryllium is a light alkaline earth metal used in metal alloys and in high-performance products in the metallurgical, aerospace, and nuclear industries. According to the Superfund database, beryllium is found in over 300 NPL sites

Effects of neutron irradiation at 70-200 °C in beryllium

NASA Astrophysics Data System (ADS)

Chakin, V. P.; Kazakov, V. A.; Melder, R. R.; Goncharenko, Yu. D.; Kupriyanov, I. B.

2002-12-01

At present beryllium is considered one of the metals to be used as a plasma facing and blanket material. This paper presents the investigations of several Russian beryllium grades fabricated by HE and HIP technologies. Beryllium specimens were irradiated in the SM reactor at 70-200 °C up to a neutron fluence (0.6-3.9)×10 22 cm -2 ( E>0.1 MeV). It is shown that the relative mass decrease of beryllium specimens that were in contact with the water coolant during irradiation achieved the value >1.5% at the maximum dose. Swelling was in the range of 0.2-1.5% and monotonically increasing with the neutron dose. During mechanical tensile and compression tests one could observe the absolute brittle destruction of the irradiated specimens at the reduced strength level in comparison to the initial state. A comparatively higher level of brittle strength was observed on beryllium specimens irradiated at 200 °C. The basic type of destruction of the irradiated beryllium specimens is brittle and intergranular with some fraction of transgranular chip.

Occupational Exposure to Beryllium. Final rule.

PubMed

2017-01-09

The Occupational Safety and Health Administration (OSHA) is amending its existing standards for occupational exposure to beryllium and beryllium compounds. OSHA has determined that employees exposed to beryllium at the previous permissible exposure limits face a significant risk of material impairment to their health. The evidence in the record for this rulemaking indicates that workers exposed to beryllium are at increased risk of developing chronic beryllium disease and lung cancer. This final rule establishes new permissible exposure limits of 0.2 micrograms of beryllium per cubic meter of air (0.2 [mu]g/m\\3\\) as an 8-hour time-weighted average and 2.0 [mu]g/m\\3\\ as a short-term exposure limit determined over a sampling period of 15 minutes. It also includes other provisions to protect employees, such as requirements for exposure assessment, methods for controlling exposure, respiratory protection, personal protective clothing and equipment, housekeeping, medical surveillance, hazard communication, and recordkeeping. OSHA is issuing three separate standards--for general industry, for shipyards, and for construction--in order to tailor requirements to the circumstances found in these sectors.

An experimental study of the composite CNT/copper coating

NASA Astrophysics Data System (ADS)

Panarin, Valentin Ye.; Svavil‧nyi, Nikolai Ye.; Khominich, Anastasiya I.

2018-03-01

This paper presents experimental results on the preparation and investigation of the carbon nanotubes-copper composite material. Carbon nanotubes (CNTs) were synthesized on silicon substrates by the chemical vapor deposition (CVD) method and then filled with copper by evaporation from a melting pot in a vacuum. Copper evenly covered both the surface of the entangled tubes and the free substrate surface between the tubes. To improve the adhesion of tubes and matrix material, a carbon substructure was grown on the surface of tubes by adding working gas plasma to the CNT synthesis area. It is proposed to use a copper coating as a diffusion barrier upon subsequent filling of the reinforcing CNT frame by a carbide-forming materials matrix with predetermined physico-mechanical and tribological properties.

Hydrothermal growth of cross-linked hyperbranched copper dendrites using copper oxalate complex

NASA Astrophysics Data System (ADS)

Truong, Quang Duc; Kakihana, Masato

2012-06-01

A facile and surfactant-free approach has been developed for the synthesis of cross-linked hyperbranched copper dendrites using copper oxalate complex as a precursor and oxalic acid as a reducing and structure-directing agent. The synthesized particles are composed of highly branched nanostructures with unusual cross-linked hierarchical networks. The formation of copper dendrites can be explained in view of both diffusion control and aggregation-based growth model accompanied by the chelation-assisted assembly. Oxalic acid was found to play dual roles as reducing and structure-directing agent based on the investigation results. The understanding on the crystal growth and the roles of oxalic acid provides clear insight into the formation mechanism of hyperbranched metal dendrites.

Arc brazing of austenitic stainless steel to similar and dissimilar metals

NASA Astrophysics Data System (ADS)

Moschini, Jamie Ian

There is a desire within both the stainless steel and automotive industries to introduce stainless steel into safety critical areas such as the crumple zone of modem cars as a replacement for low carbon mild steel. The two main reasons for this are stainless steel's corrosion resistance and its higher strength compared with mild steel. It has been anticipated that the easiest way to introduce stainless steel into the automotive industry would be to incorporate it into the existing design. The main obstacle to be overcome before this can take place is therefore how to join the stainless steel to the rest of the car body. In recent times arc brazil g has been suggested as a joining technique which will eliminate many of the problems associated with fusion welding of zinc coated mild steel to stainless steel.Similar and dissimilar parent material arc brazed joints were manufactured using three copper based filler materials and three shielding gases. The joints were tested in terms of tensile strength, impact toughness and fatigue properties. It was found that similar parent material stainless steel joints could be produced with a 0.2% proof stress in excess of the parent material and associated problems such as Liquid Metal Embrittlement were not experienced. Dissimilar parent material joints were manufactured with an ultimate tensile strength in excess of that of mild steel although during fatigue testing evidence of Liquid Metal Embrittlement was seen lowering the mean fatigue load.At the interface of the braze and stainless steel in the similar material butt joints manufactured using short circuit transfer, copper appeared to penetrate the grain boundaries of the stainless steel without embrittling the parent material. Further microscopic investigation of the interface showed that the penetration could be described by the model proposed by Mullins. However, when dissimilar metal butt joints were manufactured using spray arc transfer, penetration of copper into the stainless steel resulted in embrittlement as discussed by Glickman.

Beryllium sensitization and disease among long-term and short-term workers in a beryllium ceramics plant.

PubMed

Henneberger, P K; Cumro, D; Deubner, D D; Kent, M S; McCawley, M; Kreiss, K

2001-04-01

Workers at a beryllium ceramics plant were tested for beryllium sensitization and disease in 1998 to determine whether the plant-wide prevalence of sensitization and disease had declined since the last screening in 1992; an elevated prevalence was associated with specific processes or with high exposures; exposure-response relationships differed for long-term workers hired before the last plant-wide screening and short-term workers hired since then. Current workers were asked to complete a questionnaire and to provide blood for the beryllium lymphocyte proliferation test (BeLPT). Those with an abnormal BeLPT were classified as sensitized, and were offered clinical evaluation for beryllium disease. Task- and time-specific measurements of airborne beryllium were combined with individual work histories to compute mean, cumulative, and peak beryllium exposures for each worker. The 151 participants represented 90% of 167 eligible workers. Fifteen (9.9% of 151) had an abnormal BeLPT and were split between long-term workers (8/77 = 10.4%) and short-term workers (7/74 = 9.5%). Beryllium disease was detected in 9.1% (7/77) of long-term workers but in only 1.4% (1/74) of short-term workers (P = 0.06), for an overall prevalence of 5.3% (8/151). These prevalences were similar to those observed in the earlier survey. The prevalence of sensitization was elevated in 1992 among machinists, and was still elevated in 1998 among long-term workers (7/40 = 18%) but not among short-term workers (2/36 = 6%) with machining experience. The prevalence of sensitization was also elevated in both groups of workers for the processes of lapping, forming, firing, and packaging. The data suggested a positive relationship between peak beryllium exposure and sensitization for long-term workers and between mean, cumulative, and peak exposure and sensitization for short-term workers, although these findings were not statistically significant. Long-term workers with either a high peak exposure or work experience in forming were more likely to have an abnormal BeLPT (8/51 = 16%) than the other long-term workers (0/26, P = 0.05). All seven sensitized short-term workers either had high mean beryllium exposure or had worked longest in forming or machining (7/55 = 13% versus 0/19, P = 0.18). A plant-wide decline in beryllium exposures between the 1992 and 1998 surveys was not matched by a decline in the prevalence of sensitization and disease. Similar to findings from other studies, beryllium sensitization/disease was associated with specific processes and elevated exposures. The contrast in disease prevalence between long-term and short-term workers suggests that beryllium sensitization can occur after a short period of exposure, but beryllium disease usually requires a longer latency and/or period of exposure. The findings from this study motivated interventions to more aggressively protect and test workers, and new research into skin exposure as a route of sensitization and the contribution of individual susceptibility.

Beryllium

Cancer.gov

Learn about beryllium, exposure to which can increase your risk of lung cancer. Beryllium is a naturally occurring, light-weight metal used in products such as aerospace components, transistors, nuclear reactors, and golf clubs. Most exposures occur to workers who produce such products.

Hydrogen mobility in the lightest reversible metal hydride, LiBeH 3

DOE PAGES

Mamontov, Eugene; Kolesnikov, Alexander I.; Sampath, Sujatha; ...

2017-11-24

Lithium-beryllium metal hydrides, which are structurally related to their parent compound, BeH 2, offer the highest hydrogen storage capacity by weight among the metal hydrides (15.93 wt. % of hydrogen for LiBeH 3). Challenging synthesis protocols have precluded conclusive determination of their crystallographic structure to date, but here we analyze directly the hydrogen hopping mechanisms in BeH 2 and LiBeH 3 using quasielastic neutron scattering, which is especially sensitive to single-particle dynamics of hydrogen. We find that, unlike its parent compound BeH 2, lithium-beryllium hydride LiBeH 3 exhibits a sharp increase in hydrogen mobility above 265 K, so dramatic thatmore » it can be viewed as melting of hydrogen sublattice. We perform comparative analysis of hydrogen jump mechanisms observed in BeH 2 and LiBeH 3 over a broad temperature range. As microscopic diffusivity of hydrogen is directly related to its macroscopic kinetics, a transition in LiBeH 3 so close to ambient temperature may offer a straightforward and effective mechanism to influence hydrogen uptake and release in this very lightweight hydrogen storage compound.« less

Hydrogen mobility in the lightest reversible metal hydride, LiBeH 3

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

Mamontov, Eugene; Kolesnikov, Alexander I.; Sampath, Sujatha

Lithium-beryllium metal hydrides, which are structurally related to their parent compound, BeH 2, offer the highest hydrogen storage capacity by weight among the metal hydrides (15.93 wt. % of hydrogen for LiBeH 3). Challenging synthesis protocols have precluded conclusive determination of their crystallographic structure to date, but here we analyze directly the hydrogen hopping mechanisms in BeH 2 and LiBeH 3 using quasielastic neutron scattering, which is especially sensitive to single-particle dynamics of hydrogen. We find that, unlike its parent compound BeH 2, lithium-beryllium hydride LiBeH 3 exhibits a sharp increase in hydrogen mobility above 265 K, so dramatic thatmore » it can be viewed as melting of hydrogen sublattice. We perform comparative analysis of hydrogen jump mechanisms observed in BeH 2 and LiBeH 3 over a broad temperature range. As microscopic diffusivity of hydrogen is directly related to its macroscopic kinetics, a transition in LiBeH 3 so close to ambient temperature may offer a straightforward and effective mechanism to influence hydrogen uptake and release in this very lightweight hydrogen storage compound.« less

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

Akter, Nusnin; Wang, Mengen; Zhong, Jian-Qiang

Copper is an important industrial catalyst. The ability to manipulate the oxidation state of copper clusters in a controlled way is critical to understanding structure–reactivity relations of copper catalysts at the molecular level. Experimentally, cupric oxide surfaces or even small domains can only be stabilized at elevated temperatures and in the presence of oxygen, as copper can be easily reduced under reaction conditions. Herein bilayer silica films grown on a metallic substrate are used to trap diluted copper oxide clusters. By combining in situ experiments with first principles calculations, it is found that the confined space created by the silicamore » film leads to an increase in the energy barrier for Cu diffusion. Dispersed copper atoms trapped by the silica film can be easily oxidized by surface oxygen chemisorbed on the metallic substrate, which results in the formation and stabilization of Cu 2+ cations.« less

Copper-silver-titanium-tin filler metal for direct brazing of structural ceramics

DOEpatents

Moorhead, Arthur J.

1988-04-05

A method of joining ceramics and metals to themselves and to one another at about 800.degree. C. is described using a brazing filler metal consisting essentially of 35 to 50 at. % copper, 40 to 50 at. % silver, 1 to 15 at. % titanium, and 2 to 8 at. % tin. This method produces strong joints that can withstand high service temperatures and oxidizing environments.

Interfacial Microstructure and Mechanical Strength of 93W/Ta Diffusion-Bonded Joints with Ni Interlayer

NASA Astrophysics Data System (ADS)

Luo, Guoqiang; Zhang, Jian; Li, Meijuan; Wei, Qinqin; Shen, Qiang; Zhang, Lianmeng

2013-02-01

93W alloy and Ta metal were successfully diffusion bonded using a Ni interlayer. Ni4W was found at the W-Ni interface, and Ni3Ta and Ni2Ta were formed at the Ni-Ta interface. The shear strength of the joints increases with increasing holding time, reaching a value of 202 MPa for a joint prepared using a 90-minute holding time at 1103 K (830 °C) and 20 MPa. The fracture of this joint occurred within the Ni/Ta interface.

Modeling Deuterium Release from Plasma Implanted Surfaces

NASA Astrophysics Data System (ADS)

Grossman, A. A.; Doerner, R.; Hirooka, Y.; Luckhardt, S. C.; Sze, F. C.

1997-11-01

When energetic ions or atoms of hydrogen isotopes interact with a solid surface, they may either be reflected or they may be implanted, a slowing down process within the subsurface layer of the energetic particles to thermal velocities. Subsequent interactions of the thermalized particles are those of diffusion and trapping within the material and the possibility of re-emission from the solid via desorption. The diffusion equation and its boundary conditions govern the transport of this thermalized hydrogen within the material. Diffusivities obey an Arrhenius law over as much as fourteen orders of magnitude for the temperature range of interest for a fusion reactor first wall and divertor plate. Using TMAP4, a variety of diffusion models are set up for comparison with experiments on PISCES which involve implantation and desorption of deuterium from beryllium, tungsten, carbon and boron carbide. The parameters and characteristics of the models which give the closest fit to the experimental data are reported. At the high fluences of these experiments, it is necessary to take into account saturation effects during implantation using a separate implantation layer with thickness given by TRIM and a higher trapping to lattice ratio than in the bulk in order to model the experimental data.

Corrosion behavior and pitting susceptibility of in-situ Ti-based metallic glass matrix composites in 3.5 wt.% NaCl solutions

NASA Astrophysics Data System (ADS)

Xu, K. K.; Lan, A. D.; Yang, H. J.; Han, P. D.; Qiao, J. W.

2017-11-01

The Ti62Zr12V13Cu4Be9, Ti58Zr16V10Cu4Be12, Ti46Zr20V12Cu5Be17, and Ti40Zr24V12Cu5Be19 metallic glass matrix composites (MGMCs) were prepared by copper mould casting. The corrosion resistance and the pitting susceptibility of Ti-based MGMCs were tested on their cross-sectional areas in 3.5 wt.% NaCl solutions by potentiodynamic polarization measurements. The composites with lower Ti contents (Ti40Zr24V12Cu5Be19 and Ti46Zr20V12Cu5Be17) exhibit a low resistance to the chloride induced pitting and local corrosion. The preferential dissolution of amorphous matrix is explained by the high chemical reactivity of beryllium element compared to that of stable dendrites and by the detected lower Ti and V contents. However, fairly good passivity was found in the composite with higher Ti contents (Ti62Zr12V13Cu4Be9). XPS measurements revealed that protective Ti-enriched oxide film was formed on the composite surface, additionally, lower content of beryllium element in amorphous matrix hinder the selective corrosion of amorphous matrix. The assessment of experimental observation leads to a proposed corrosion mechanism involving selective dissolution of amorphous matrix and chloride induced pitting process.

Origin of native copper in the Paraná volcanic province, Brazil, integrating Cu stable isotopes in a multi-analytical approach

NASA Astrophysics Data System (ADS)

Baggio, Sérgio Benjamin; Hartmann, Léo Afraneo; Lazarov, Marina; Massonne, Hans-Joachim; Opitz, Joachim; Theye, Thomas; Viefhaus, Tillmann

2018-03-01

Different hypotheses exist on the origin of native copper mineralization in the Paraná volcanic province that invoke magmatic, late magmatic, or hydrothermal events. The average copper content in the host basalts is 200 ppm. Native copper occurs as dendrites in cooling joints, fractures, and cavities within amygdaloidal crusts. Cuprite, tenorite, chrysocolla, malachite, and azurite occur in breccias at the top of the lava flows. Chemical analyses, X-ray diffraction, Raman spectrometry, electron microprobe analyses, LA-ICP-MS, and Cu isotope analyses were used to evaluate the origin of native copper in the volcanic province. Copper contents in magnetite of the host basalt are close to 1 wt.%, whereas clinopyroxene contains up to 0.04 wt.% Cu. Cretaceous hydrothermal alteration of magnetite and clinopyroxene released copper to generate hydrothermal copper mineralization. The isotopic composition of the native copper in the Paraná volcanic province varies from -0.9‰ in the southeastern portion (Rio Grande do Sul state) to 1.9‰ in the central portion (Paraná state) of the province. This study supports a hydrothermal origin followed by supergene enrichment for native copper in the Paraná volcanic province.

Adsorption of beryllium atoms and clusters both on graphene and in a bilayer of graphite investigated by DFT.

PubMed

Ferro, Yves; Fernandez, Nicolas; Allouche, Alain; Linsmeier, Christian

2013-01-09

We herein investigate the interaction of beryllium with a graphene sheet and in a bilayer of graphite by means of periodic DFT calculations. In all cases, we find the beryllium atoms to be more weakly bonded on graphene than in the bilayer. Be(2) forms both magnetic and non-magnetic structures on graphene depending on the geometrical configuration of adsorption. We find that the stability of the Be/bilayer system increases with the size of the beryllium clusters inserted into the bilayer of graphite. We also find a charge transfer from beryllium to the graphite layers. All these results are analysed in terms of electronic structure.

Low temperature coefficient of resistance and high gage factor in beryllium-doped silicon

NASA Technical Reports Server (NTRS)

Robertson, J. B.; Littlejohn, M. A.

1974-01-01

The gage factor and resistivity of p-type silicon doped with beryllium was studied as a function of temperature, crystal orientation, and beryllium doping concentration. It was shown that the temperature coefficient of resistance can be varied and reduced to zero near room temperature by varying the beryllium doping level. Similarly, the magnitude of the piezoresistance gage factor for beryllium-doped silicon is slightly larger than for silicon doped with a shallow acceptor impurity such as boron, whereas the temperature coefficient of piezoresistance is about the same for material containing these two dopants. These results are discussed in terms of a model for the piezoresistance of compensated p-type silicon.

Detection of beryllium by laser-induced-breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Radziemski, Leon J.; Cremers, David A.; Loree, Thomas R.

Using the new technique of laser-induced-breakdown spectroscopy (LIBS) a limit of detection was measured for beryllium in air of 0.5 ng/g ( w/w), which is one-third of the OSHA limit for the 8-h average exposure to beryllium. Approximately linear working curves were obtained over the concentration range 0.5 to 2 × 10 4 ng g -1. The potential application of this technique to a beryllium monitoring instrument is discussed.

Preparing the future post-mortem analysis of beryllium-based JET and ITER samples by multi-wavelengths Raman spectroscopy on implanted Be, and co-deposited Be

NASA Astrophysics Data System (ADS)

Rusu, M. I.; Pardanaud, C.; Ferro, Y.; Giacometti, G.; Martin, C.; Addab, Y.; Roubin, P.; Minissale, M.; Ferri, L.; Virot, F.; Barrachin, M.; Lungu, C. P.; Porosnicu, C.; Dinca, P.; Lungu, M.; Köppen, M.; Hansen, P.; Linsmeier, Ch.

2017-07-01

This study demonstrates that Raman microscopy is a suitable technique for future post mortem analyses of JET and ITER plasma facing components. We focus here on laboratory deposited and bombarded samples of beryllium and beryllium carbides and start to build a reference spectral databases for fusion relevant beryllium-based materials. We identified the beryllium phonon density of states, its second harmonic and E 2G and B 2G second harmonic and combination modes for defective beryllium in the spectral range 300-700 and 700-1300 cm-1, lying close to Be-D modes of beryllium hydrides. We also identified beryllium carbide signature, Be2C, combining Raman microscopy and DFT calculation. We have shown that, depending on the optical constants of the material probed, in depth sensitivity at the nanometer scale can be performed using different wavelengths. This way, we demonstrate that multi-wavelength Raman microscopy is sensitive to in-depth stress caused by ion implantation (down to  ≈30 nm under the surface for Be) and Be/C concentration (down to 400 nm or more under the surface for Be+C), which is a main contribution of this work. The depth resolution reached can then be adapted for studying the supersaturated surface layer found on tokamak deposits.

Investigation of ITER candidate beryllium grades irradiated at high temperature

NASA Astrophysics Data System (ADS)

Kupriyanov, I. B.; Gorokhov, V. A.; Melder, R. R.; Ostrovsky, Z. E.; Gervash, A. A.

1998-10-01

Beryllium is one of the main candidate materials both for the neutron multiplier in a solid breeding blanket and for the plasma facing components. That is why the investigation of beryllium behaviour under the typical for fusion reactor loading, in particular under the neutron irradiation, is of a great importance. This paper presents some results of investigation of five beryllium grades (DshG-200, TR-30, TshG-56, TRR, TE-30, TIP-30) fabricated by VNIINM, Russia, and one (S-65) fabricated by Brush Wellman, USA. The average grain size of the investigated beryllium grades varied from 8 to 40 μm, beryllium oxide content was 0.7-3.2 wt.%, initial tensile strength 250-680 MPa. All the samples were irradiated in active zone of SM-3 reactor of 650-700°C up to the fast neutron fluence (5.5-6.2) × 10 21 cm -2 (2.7-3.0 dpa, helium content up to 1150 appm), E > 0.1 MeV. Irradiation swelling of the materials was revealed to be in the range of 0.3-1.7%. Beryllium grades TR-30 and TRR having the smallest grain size and highest beryllium oxide content, demonstrated minimal swelling, which did not exceed 0.3% at 700°C and fluence 5.5 × 10 21 cm -2. Mechanical properties and microstructure parameters measured before and after irradiation are also presented.

Extraction of beryllium from refractory beryllium oxide with dilute ammonium bifluoride and determination by fluorescence: a multiparameter performance evaluation.

PubMed

Goldcamp, Michael J; Goldcamp, Diane M; Ashley, Kevin; Fernback, Joseph E; Agrawal, Anoop; Millson, Mark; Marlow, David; Harrison, Kenneth

2009-12-01

Beryllium exposure can cause a number of deleterious health effects, including beryllium sensitization and the potentially fatal chronic beryllium disease. Efficient methods for monitoring beryllium contamination in workplaces are valuable to help prevent dangerous exposures to this element. In this work, performance data on the extraction of beryllium from various size fractions of high-fired beryllium oxide (BeO) particles (from < 32 microm up to 212 microm) using dilute aqueous ammonium bifluoride (ABF) solution were obtained under various conditions. Beryllium concentrations were determined by fluorescence using a hydroxybenzoquinoline fluorophore. The effects of ABF concentration and volume, extraction temperature, sample tube types, and presence of filter or wipe media were examined. Three percent ABF extracts beryllium nearly twice as quickly as 1% ABF; extraction solution volume has minimal influence. Elevated temperatures increase the rate of extraction dramatically compared with room temperature extraction. Sample tubes with constricted tips yield poor extraction rates owing to the inability of the extraction medium to access the undissolved particles. The relative rates of extraction of Be from BeO of varying particle sizes were examined. Beryllium from BeO particles in fractions ranging from less than 32 microm up to 212 microm were subjected to various extraction schemes. The smallest BeO particles are extracted more quickly than the largest particles, although at 90 degrees C even the largest BeO particles reach nearly quantitative extraction within 4 hr in 3% ABF. Extraction from mixed cellulosic-ester filters, cellulosic surface-sampling filters, wetted cellulosic dust wipes, and cotton gloves yielded 90% or greater recoveries. Scanning electron microscopy of BeO particles, including partially dissolved particles, shows that dissolution in dilute ABF occurs not just on the exterior surface but also via accessing particles' interiors due to porosity of the BeO material. Comparison of dissolution kinetics data shows that as particle diameter approximately doubles, extraction time is increased by a factor of about 1.5, which is consistent with the influence of porosity on dissolution.

40 CFR 61.31 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... associated elements. (b) Extraction plant means a facility chemically processing beryllium ore to beryllium..., electrochemical machining, etching, or other similar operations. (e) Ceramic plant means a manufacturing plant... which contains more than 0.1 percent beryllium by weight. (k) Propellant plant means any facility...

40 CFR 61.31 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... associated elements. (b) Extraction plant means a facility chemically processing beryllium ore to beryllium..., electrochemical machining, etching, or other similar operations. (e) Ceramic plant means a manufacturing plant... which contains more than 0.1 percent beryllium by weight. (k) Propellant plant means any facility...

Imaging osteoarthritis in the knee joints using x-ray guided diffuse optical tomography

NASA Astrophysics Data System (ADS)

Zhang, Qizhi; Yuan, Zhen; Sobel, Eric S.; Jiang, Huabei

2010-02-01

In our previous studies, near-infrared (NIR) diffuse optical tomography (DOT) had been successfully applied to imaging osteoarthritis (OA) in the finger joints where significant difference in optical properties of the joint tissues was evident between healthy and OA finger joints. Here we report for the first time that large joints such as the knee can also be optically imaged especially when DOT is combined with x-ray tomosynthesis where the 3D image of the bones from x-ray is incorporated into the DOT reconstruction as spatial a priori structural information. This study demonstrates that NIR light can image large joints such as the knee in addition to finger joints, which will drastically broaden the clinical utility of our x-ray guided DOT technique for OA diagnosis.

Hydrothermal corrosion of silicon carbide joints without radiation

DOE PAGES

Koyanagi, Takaaki; Katoh, Yutai; Terrani, Kurt A.; ...

2016-09-28

In this paper, hydrothermal corrosion of four types of the silicon carbide (SiC) to SiC plate joints were investigated under pressurized water reactor and boiling water reactor relevant chemical conditions without irradiation. The joints were formed by metal diffusion bonding using molybdenum or titanium interlayer, reaction sintering using Ti—Si—C system, and SiC nanopowder sintering. Most of the joints withstood the corrosion tests for five weeks. The recession of the SiC substrates was limited. Based on the recession of the bonding layers, it was concluded that all the joints except for the molybdenum diffusion bond are promising under the reducing environmentsmore » without radiation. Finally, the SiC nanopowder sintered joint was the most corrosion tolerant under the oxidizing environment among the four joints.« less

Thermal Stability of Silver Paste Sintering on Coated Copper and Aluminum Substrates

NASA Astrophysics Data System (ADS)

Pei, Chun; Chen, Chuantong; Suganuma, Katsuaki; Fu, Guicui

2018-01-01

The thermal stability of silver (Ag) paste sintering on coated copper (Cu) and aluminum (Al) substrates has been investigated. Instead of conventional zincating or nickel plating, magnetron sputtering was used to achieve coating with titanium (Ti) and Ag. Silicon (Si) chips were bonded to coated Cu and Al substrates using a mixture of submicron Ag flakes and particles under 250°C and 0.4 MPa for 30 min. The joints were then subject to aging testing at 250°C for duration of 200 h, 500 h, and 1000 h. Two types of joints exhibited satisfactory initial shear strength above 45 MPa. However, the shear strength of the joints on Al substrate decreased to 28 MPa after 1000 h of aging, while no shear strength decline was detected for the joints on Cu substrate. Fracture surface analysis revealed that the vulnerable points of the two types of joints were (1) the Ag layer and (2) the interface between the Ti layer and Cu substrate. Based on the results of scanning electron microscopy (SEM), energy-dispersive x-ray spectroscopy (EDS), and simulations, cracks in the Ag layer were identified as the cause of the shear strength degradation in the joints on Al substrate. The interface evolution of the joints on Cu substrate was ascribed to Cu migration and discontinuity points that initialized in the Ti layer. This study reveals that Al exhibited superior thermal stability with sintered Ag paste.

Optimizing the performance of catalytic traps for hydrocarbon abatement during the cold-start of a gasoline engine.

PubMed

Puértolas, B; Navlani-García, M; García, T; Navarro, M V; Lozano-Castelló, D; Cazorla-Amorós, D

2014-08-30

A key target to reduce current hydrocarbon emissions from vehicular exhaust is to improve their abatement under cold-start conditions. Herein, we demonstrate the potential of factorial analysis to design a highly efficient catalytic trap. The impact of the synthesis conditions on the preparation of copper-loaded ZSM-5 is clearly revealed by XRD, N2 sorption, FTIR, NH3-TPD, SEM and TEM. A high concentration of copper nitrate precursor in the synthesis improves the removal of hydrocarbons, providing both strong adsorption sites for hydrocarbon retention at low temperature and copper oxide nanoparticles for full hydrocarbon catalytic combustion at high temperature. The use of copper acetate precursor leads to a more homogeneous dispersion of copper oxide nanoparticles also providing enough catalytic sites for the total oxidation of hydrocarbons released from the adsorption sites, although lower copper loadings are achieved. Thus, synthesis conditions leading to high copper loadings jointly with highly dispersed copper oxide nanoparticles would result in an exceptional catalytic trap able to reach superior hydrocarbon abatement under highly demanding operational conditions. Copyright © 2014 Elsevier B.V. All rights reserved.

Exposure and genetics increase risk of beryllium sensitisation and chronic beryllium disease in the nuclear weapons industry

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

Van Dyke, M. V.; Colorado State Univ., Fort Collins, CO; Martyny, John W.

2011-04-02

Beryllium sensitisation (BeS) and chronic beryllium disease (CBD) are caused by exposure to beryllium with susceptibility affected by at least one well-studied genetic host factor, a glutamic acid residue at position 69 (E69) of the HLA-DPb chain (DPbE69). However, the nature of the relationship between exposure and carriage of the DPbE69 genotype has not been well studied. The goal of this study was to determine the relationship between DP{beta}E69 and exposure in BeS and CBD. Current and former workers (n=181) from a US nuclear weapons production facility, the Y-12 National Security Complex (Oak Ridge, Tennessee, USA), were enrolled in amore » case-control study including 35 individuals with BeS and 19 with CBD. HLA-DPB1 genotypes were determined by PCR-SSP. Beryllium exposures were assessed through worker interviews and industrial hygiene assessment of work tasks. After removing the confounding effect of potential beryllium exposure at another facility, multivariate models showed a sixfold (OR 6.06, 95% CI 1.96 to 18.7) increased odds for BeS and CBD combined among DP{beta}E69 carriers and a fourfold (OR 3.98, 95% CI 1.43 to 11.0) increased odds for those exposed over an assigned lifetime-weighted average exposure of 0.1 {micro}g/m{sup 3}. Those with both risk factors had higher increased odds (OR 24.1, 95% CI 4.77 to 122). DP{beta}E69 carriage and high exposure to beryllium appear to contribute individually to the development of BeS and CBD. Among workers at a beryllium-using facility, the magnitude of risk associated with either elevated beryllium exposure or carriage of DP{beta}E69 alone appears to be similar.« less

Characterization of beryllium deformation using in-situ x-ray diffraction

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

Magnuson, Eric Alan; Brown, Donald William; Clausen, Bjorn

2015-08-24

Beryllium’s unique mechanical properties are extremely important in a number of high performance applications. Consequently, accurate models for the mechanical behavior of beryllium are required. However, current models are not sufficiently microstructure aware to accurately predict the performance of beryllium under a range of processing and loading conditions. Previous experiments conducted using the SMARTS and HIPPO instruments at the Lujan Center(LANL), have studied the relationship between strain rate and texture development, but due to the limitations of neutron diffraction studies, it was not possible to measure the response of the material in real-time. In-situ diffraction experiments conducted at the Advancedmore » Photon Source have allowed the real time measurement of the mechanical response of compressed beryllium. Samples of pre-strained beryllium were reloaded orthogonal to their original load path to show the reorientation of already twinned grains. Additionally, the in-situ experiments allowed the real time tracking of twin evolution in beryllium strained at high rates. The data gathered during these experiments will be used in the development and validation of a new, microstructure aware model of the constitutive behavior of beryllium.« less

Formation of copper precipitates in silicon

NASA Astrophysics Data System (ADS)

Flink, Christoph; Feick, Henning; McHugo, Scott A.; Mohammed, Amna; Seifert, Winfried; Hieslmair, Henry; Heiser, Thomas; Istratov, Andrei A.; Weber, Eicke R.

1999-12-01

The formation of copper precipitates in silicon was studied after high-temperature intentional contamination of p- and n-type FZ and Cz-grown silicon and quench to room temperature. With the Transient Ion Drift (TID) technique on p-type silicon a critical Fermi level position at EC-0.2 eV was found. Only if the Fermi level position, which is determined by the concentrations of the acceptors and the copper donors, surpasses this critical value precipitation takes place. If the Fermi level is below this level the supersaturated interstitial copper diffuses out. An electrostatic precipitation model is introduced that correlates the observed precipitation behavior with the electrical activity of the copper precipitates as detected with Deep Level Transient Spectroscopy (DLTS) on n-type and with Minority Carrier Transient Spectroscopy (MCTS) on p-type silicon.

Effect of Post Treatment For Cu-Cr Source/Drain Electrodes on a-IGZO TFTs.

PubMed

Hu, Shiben; Fang, Zhiqiang; Ning, Honglong; Tao, Ruiqiang; Liu, Xianzhe; Zeng, Yong; Yao, Rihui; Huang, Fuxiang; Li, Zhengcao; Xu, Miao; Wang, Lei; Lan, Linfeng; Peng, Junbiao

2016-07-27

We report a high-performance amorphous Indium-Gallium-Zinc-Oxide (a-IGZO) thin-film transistor (TFT) with new copper-chromium (Cu-Cr) alloy source/drain electrodes. The TFT shows a high mobility of 39.4 cm 2 ·V - 1 ·s - 1 a turn-on voltage of -0.8 V and a low subthreshold swing of 0.47 V/decade. Cu diffusion is suppressed because pre-annealing can protect a-IGZO from damage during the electrode sputtering and reduce the copper diffusion paths by making film denser. Due to the interaction of Cr with a-IGZO, the carrier concentration of a-IGZO, which is responsible for high mobility, rises.

Effect of Post Treatment For Cu-Cr Source/Drain Electrodes on a-IGZO TFTs

PubMed Central

Hu, Shiben; Fang, Zhiqiang; Ning, Honglong; Tao, Ruiqiang; Liu, Xianzhe; Zeng, Yong; Yao, Rihui; Huang, Fuxiang; Li, Zhengcao; Xu, Miao; Wang, Lei; Lan, Linfeng; Peng, Junbiao

2016-01-01

We report a high-performance amorphous Indium-Gallium-Zinc-Oxide (a-IGZO) thin-film transistor (TFT) with new copper-chromium (Cu-Cr) alloy source/drain electrodes. The TFT shows a high mobility of 39.4 cm2·V−1·s−1 a turn-on voltage of −0.8 V and a low subthreshold swing of 0.47 V/decade. Cu diffusion is suppressed because pre-annealing can protect a-IGZO from damage during the electrode sputtering and reduce the copper diffusion paths by making film denser. Due to the interaction of Cr with a-IGZO, the carrier concentration of a-IGZO, which is responsible for high mobility, rises. PMID:28773743

Network of Porosity Formed in Ultrafine-Grained Copper Produced by Equal Channel Angular Pressing

NASA Astrophysics Data System (ADS)

Ribbe, Jens; Baither, Dietmar; Schmitz, Guido; Divinski, Sergiy V.

2009-04-01

Radiotracer experiments on diffusion of Ni63 and Rb86 in severely deformed commercially pure copper (8 passes of equal channel angular pressing) reveal unambiguously the existence of ultrafast transport paths. A fraction of these paths remains in the material even after complete recrystallization. Scanning electron microscopy and focused ion beam techniques are applied. Deep grooves are found which are related to original high-energy interfaces. In-depth sectioning near corresponding triple junctions reveals clearly multiple microvoids or microcracks caused by the severe deformation. Long-range tracer penetration over tens of micrometers proves that these submicrometer-large defects are connected by highly diffusive paths and that they appear with significant frequency.

Development of Surfaces Optically Suitable for Flat Solar Panels. [using a reflectometer which separately evaluates spectral and diffuse reflectivities of surfaces

NASA Technical Reports Server (NTRS)

1979-01-01

A reflectometer which can separately evaluate the spectral and diffuse reflectivities of surfaces is described. A phase locked detection system for the reflectometer is also described. A selective coating on aluminum potentially useful for flat plate solar collector applications is presented. The coating is composed of strongly bound copper oxide (divalent) and is formed by an etching process performed on an aluminum alloy with high copper content. Fabrication costs are expected to be small due to the one stop fabrication process. A number of conclusions gathered from the literature as to the required optical properties of flat plate solar collectors are discussed.

The Effects of Borides on the Mechanical Properties of TLPB Repaired Inconel 738 Superalloy

NASA Astrophysics Data System (ADS)

Wei, J.; Ye, Y.; Sun, Z.; Zou, G.; Bai, H.; Wu, A.; Liu, L.

2017-10-01

The transient liquid phase diffusion bonding (TLPB) method was used to repair an artificial crack in Inconel 738, which was notched by a femtosecond laser. Mixed ratios of BNi-1a:DF-4B were investigated at the bonding temperature of 1373 K (1100 °C) for 2 to 36 hours. The effect of borides on the mechanical properties of TLPB repaired joints was studied through analysis of the microstructure, fracture path, and morphology observations. The borides formation, morphology, distribution, and joints strength were studied in detail. The results showed that the diffusion of B can either increase or decrease the joint strength, depending on its distribution and morphology. The amount of large blocky Ni-B compounds in the precipitate zone were reduced with increasing holding time, which resulted in an increase in joint strength. Nevertheless, further increasing the holding time led to a decrease in joint strength because of the formation of continuous acicular borides in the diffusion-affected zone. The fracture modes of TLPB joints were also discussed on the basis of the microstructure and fractography.

Feasibility study for detecting copper contaminants in transformer insulation using laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Aparna, N.; Vasa, Nilesh J.; Sarathi, R.; Rajan, J. Sundara

2014-10-01

In recent times, copper sulphide (Cu2S) diffusion in the transformer insulation is a major problem reducing the life of transformers. It is therefore essential to identify a simple methodology to understand the diffusion of Cu2S into the solid insulation [oil impregnated pressboard (OIP)]. In the present work, laser-induced breakdown spectroscopy (LIBS) was adopted to study the diffusion of Cu2S into the pressboard insulation and to determine the depth of diffusion. The diffusion of Cu2S in pressboard was confirmed by electrical discharge studies. In general, flashover voltage and increase in ageing duration of pressboard insulation/Cu concentration had inverse relationship. The characteristic emission lines were also studied through optical emission spectroscopy. Based on LIBS studies with Cu powder dispersed pressboard samples, Cu I emission lines were found to be resolvable up to a lowest concentration of 5 μg/cm2. The LIBS intensity ratio of Cu I-Ca II emission lines were found to increase with increase in the ageing duration of the OIP sample. LIBS studies with OIP samples showed an increase in the optical emission lifetime. LIBS results were in agreement with the electrical discharge studies.

Friction Stir Processing of Copper-Coated SiC Particulate-Reinforced Aluminum Matrix Composite

PubMed Central

Huang, Chih-Wei; Aoh, Jong-Ning

2018-01-01

In the present work, we proposed a novel friction stir processing (FSP) to produce a locally reinforced aluminum matrix composite (AMC) by stirring copper-coated SiC particulate reinforcement into Al6061 alloy matrix. Electroless-plating process was applied to deposit the copper surface coating on the SiC particulate reinforcement for the purpose of improving the interfacial adhesion between SiC particles and Al matrix. The core-shell SiC structure provides a layer for the atomic diffusion between aluminum and copper to enhance the cohesion between reinforcing particles and matrix on one hand, the dispersion of fine copper in the Al matrix during FSP provides further dispersive strengthening and solid solution strengthening, on the other hand. Hardness distribution and tensile results across the stir zone validated the novel concept in improving the mechanical properties of AMC that was realized via FSP. Optical microscope (OM) and Transmission Electron Microscopy (TEM) investigations were conducted to investigate the microstructure. Energy dispersive spectrometer (EDS), electron probe micro-analyzer (EPMA), and X-ray diffraction (XRD) were explored to analyze the atomic inter-diffusion and the formation of intermetallic at interface. The possible strengthening mechanisms of the AMC containing Cu-coated SiC particulate reinforcement were interpreted. The concept of strengthening developed in this work may open a new way of fabricating of particulate reinforced metal matrix composites. PMID:29652846

The mechanical behavior of cross-rolled beryllium sheet

NASA Technical Reports Server (NTRS)

Henkener, J. A.; Spiker, I. K.; Castner, W. L.

1992-01-01

In response to the failure of a conical section of the Insat C satellite during certification testing, the use of beryllium for payload structures, particularly in sheet product form, is being reevaluated. A test program was initiated to study the tensile, shear, and out-of-plane failure modes of beryllium cross-rolled sheet and to apply data to the development of an appropriate failure criterion. Tensile test results indicated that sanding the surface of beryllium sheet has no significant effect on yield strength but can produce a profound reduction in ultimate strength and results obtained by finite element analysis. Critical examination of these test results may contribute to the modification of a JSC policy for the use of beryllium in orbiter and payload structures.

Modeling of copper sorption onto GFH and design of full-scale GFH adsorbers.

PubMed

Steiner, Michele; Pronk, Wouter; Boller, Markus A

2006-03-01

During rain events, copper wash-off occurring from copper roofs results in environmental hazards. In this study, columns filled with granulated ferric hydroxide (GFH) were used to treat copper-containing roof runoff. It was shown that copper could be removed to a high extent. A model was developed to describe this removal process. The model was based on the Two Region Model (TRM), extended with an additional diffusion zone. The extended model was able to describe the copper removal in long-term experiments (up to 125 days) with variable flow rates reflecting realistic runoff events. The four parameters of the model were estimated based on data gained with specific column experiments according to maximum sensitivity for each parameter. After model validation, the parameter set was used for the design of full-scale adsorbers. These full-scale adsorbers show high removal rates during extended periods of time.

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.

Novel Method of Aluminum to Copper Bonding by Cold Spray

NASA Astrophysics Data System (ADS)

Fu, Si-Lin; Li, Cheng-Xin; Wei, Ying-Kang; Luo, Xiao-Tao; Yang, Guan-Jun; Li, Chang-Jiu; Li, Jing-Long

2018-04-01

Cold spray bonding (CSB) has been proposed as a new method for joining aluminum and copper. At high speeds, solid Al particles impacted the groove between the two substrates to form a bond between Al and Cu. Compared to traditional welding technologies, CSB does not form distinct intermetallic compounds. Large stainless steel particles were introduced into the spray powders as in situ shot peen particles to create a dense Al deposit and to improve the bond strength of joints. It was discovered that introducing shot peen particles significantly improved the flattening ratio of the deposited Al particles. Increasing the proportion of shot peen particles from 0 to 70 vol.% decreased the porosity of the deposits from 12.4 to 0.2%, while the shear strength of joints significantly increased. The tensile test results of the Al-Cu joints demonstrated that cracks were initiated at the interface between the Al and the deposit. The average tensile strength was 71.4 MPa and could reach 81% of the tensile strength of pure Al.

Brazing of Carbon Carbon Composites to Cu-clad Molybdenum for Thermal Management Applications

NASA Technical Reports Server (NTRS)

Singh, M.; Asthana, R.; Shpargel, T> P.

2007-01-01

Advanced carbon carbon composites were joined to copper-clad molybdenum (Cu/Mo) using four active metal brazes containing Ti (Cu ABA, Cusin-1 ABA, Ticuni, and Ticusil) for potential use in thermal management applications. The brazed joints were characterized using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and Knoop microhardness measurements across the joint region. Metallurgically sound C-C/Cu/Mo joints, devoid of interfacial cracks formed in all cases. The joint interfaces were preferentially enriched in Ti, with Cu ABA joints exhibiting the largest interfacial Ti concentrations. The microhardness measurements revealed hardness gradients across the joint region, with a peak hardness of 300-350 KHN in Cusin-1 ABA and Ticusil joints and 200-250 KHN in Cu ABA and Ticuni joints, respectively.

IRIS TOXICOLOGICAL REVIEW AND SUMMARY DOCUMENTS FOR BERYLLIUM AND COMPOUNDS

EPA Science Inventory

EPA's assessment of the noncancer health effects and carcinogenic potential of Beryllium was added to the IRIS database in 1998. The IRIS program is updating the IRIS assessment for Beryllium. This update will incorporate health effects information published since the last assess...

40 CFR 61.41 - Definitions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium Rocket Motor..., or in this section as follows: (a) Rocket motor test site means any building, structure, facility, or installation where the static test firing of a beryllium rocket motor and/or the disposal of beryllium...

40 CFR 61.41 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium Rocket Motor..., or in this section as follows: (a) Rocket motor test site means any building, structure, facility, or installation where the static test firing of a beryllium rocket motor and/or the disposal of beryllium...

40 CFR 61.41 - Definitions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium Rocket Motor..., or in this section as follows: (a) Rocket motor test site means any building, structure, facility, or installation where the static test firing of a beryllium rocket motor and/or the disposal of beryllium...

40 CFR 61.41 - Definitions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium Rocket Motor..., or in this section as follows: (a) Rocket motor test site means any building, structure, facility, or installation where the static test firing of a beryllium rocket motor and/or the disposal of beryllium...

40 CFR 61.41 - Definitions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS National Emission Standard for Beryllium Rocket Motor..., or in this section as follows: (a) Rocket motor test site means any building, structure, facility, or installation where the static test firing of a beryllium rocket motor and/or the disposal of beryllium...

DETERMINING BERYLLIUM IN DRINKING WATER BY GRAPHITE FURNACE ATOMIC ABSORPTION SPECTROSCOPY

EPA Science Inventory

A direct graphite furnace atomic absorption spectroscopy method for the analysis of beryllium in drinking water has been derived from a method for determining beryllium in urine. Ammonium phosphomolybdate and ascorbic acid were employed as matrix modifiers. The matrix modifiers s...

Cryogenic Properties of Aluminum Beryllium and Beryllium Materials

NASA Technical Reports Server (NTRS)

Gamwell, Wayne R.; McGill, Preston B.

2003-01-01

Ultimate tensile strength, yield strength, and elongation were obtained for the aluminum-beryllium alloy, AlBeMetl62 (38%Al-62%Be), at cryogenic (-195.5 C (-320 F) and (-252.8 C) (-423 F)) temperatures, and for an optical grade beryllium, O-30H (99%Be), at -252.8 C. AlBeMetl62 material was purchased to the requirements of SAE-AMS7912, "Aluminum-Beryllium Alloy, Extrusions." O-30H material was purchased to the requirements of Brush Wellman Inc. specification O-30H Optical Grade Beryllium. The ultimate tensile and yield strengths for extruded AlBeMetl62 material increased with decreasing temperature, and the percent elongation decreased with decreasing temperature. Design properties for the ultimate tensile strength, yield strength, and percent elongation for extruded AlBeMetl62 were generated. It was not possible to distinguish a difference in the room and cryogenic ultimate strength for the hot isostatically pressed (HIP'ed) O-30H material. The O30H elongation decreased with decreasing temperature.

Methods for the mitigation of the chemical reactivity of beryllium in steam

NASA Astrophysics Data System (ADS)

Druyts, F.; Alves, E. C.; Wu, C. H.

2004-08-01

In the safety assessment of future fusion reactors, the reaction of beryllium with steam remains one of the main concerns. In case of a loss of coolant accident (LOCA), the use of beryllium in combination with pressurised water as coolant can lead to excessive hydrogen production due to the reaction Be + H 2O = BeO + H 2 + heat. Therefore, we started an R&D programme aimed at investigating mitigation methods for the beryllium/steam reaction. Beryllium samples were implanted with either calcium or aluminium ions in a 210 kV ion implanter at ITN Lisbon. The chemical reactivity of these samples in steam was measured at SCK • CEN in a dedicated experimental facility providing coupled thermogravimetry/mass spectrometry. In comparison to reference undoped material, the reactivity of doped beryllium after 30 min of exposure decreased with a factor 2 to 4. The mitigating effect was higher for calcium-doped than for aluminium-doped samples.

Copper(II) complexes of methimazole, an anti Grave's disease drug. Synthesis, characterization and its potential biological behavior as alkaline phosphatase inhibitor.

PubMed

Urquiza, Nora M; Manca, Silvia G; Moyano, María A; Dellmans, Raquel Arrieta; Lezama, Luis; Rojo, Teófilo; Naso, Luciana G; Williams, Patricia A M; Ferrer, Evelina G

2010-04-01

Methimazole (MeimzH) is an anti-thyroid drug and the first choice for patients with Grave's disease. Two new copper(II) complexes of this drug: [Cu(MeimzH)(2)(NO(3))(2)]*0.5H(2)O and [Cu(MeimzH)(2)(H(2)O)(2)](NO(3))(2)*H(2)O were synthesized and characterized by elemental analysis, dissolution behavior, thermogravimetric analysis and UV-vis, diffuse reflectance, FTIR and EPR spectroscopies. As it is known that copper(II) cation can act as an inhibitor of alkaline phosphatase (ALP), the inhibitory effect of methimazole and its copper(II) complexes on ALP activity has also been investigated.

Development of the activated diffusion brazing process for fabrication of finned shell to strut turbine blades

NASA Technical Reports Server (NTRS)

Wilbers, L. G.; Berry, T. F.; Kutchera, R. E.; Edmonson, R. E.

1971-01-01

The activated diffusion brazing process was developed for attaching TD-NiCr and U700 finned airfoil shells to matching Rene 80 struts obstructing the finned cooling passageways. Creep forming the finned shells to struts in combination with precise preplacement of brazing alloy resulted in consistently sound joints, free of cooling passageway clogging. Extensive tensile and stress rupture testing of several joint orientation at several temperatures provided a critical assessment of joint integrity of both material combinations. Trial blades of each material combination were fabricated followed by destructive metallographic examination which verified high joint integrity.

Native oxide formation on pentagonal copper nanowires: A TEM study

NASA Astrophysics Data System (ADS)

Hajimammadov, Rashad; Mohl, Melinda; Kordas, Krisztian

2018-06-01

Hydrothermally synthesized copper nanowires were allowed to oxidize in air at room temperature and 30% constant humidity for the period of 22 days. The growth of native oxide layer was followed up by high-resolution transmission electron microscopy and diffraction to reveal and understand the kinetics of the oxidation process. Copper oxides appear in the form of differently oriented crystalline phases around the metallic core as a shell-like layer (Cu2O) and as nanoscopic islands (CuO) on the top of that. Time dependent oxide thickness data suggests that oxidation follows the field-assisted growth model at the beginning of the process, as practically immediately an oxide layer of ∼2.8 nm thickness develops on the surface. However, after this initial rapid growth, the local field attenuates and the classical parabolic diffusion limited growth plays the main role in the oxidation. Because of the single crystal facets on the side surface of penta-twinned Cu nanowires, the oxidation rate in the diffusion limited regime is lower than in polycrystalline films.

Aspects of the structural evolution of lead-free solder joints

NASA Astrophysics Data System (ADS)

Zribi, A.; Kinyanjui, R.; Borgesen, P.; Zavalij, L.; Cotts, E. J.

2002-06-01

Studies of the formation of intermetallic compounds at some lead-free solder/metallization interfaces are briefly reviewed in this article. SnAgCu/Ni and SnAgCu/Cu interfaces are examined in particular. It has been found that (Cu,Ni)6Sn5 forms at SnAgCu/Ni interfaces until copper is depleted from the solder matrix. This article also contrasts the formation of (Au,Ni)Sn4 and related compounds in PbSn/Ni solder joints and lead-free solder joints.

Microstructure and properties of pure iron/copper composite cladding layers on carbon steel

NASA Astrophysics Data System (ADS)

Wan, Long; Huang, Yong-xian; Lü, Shi-xiong; Huang, Ti-fang; Lü, Zong-liang

2016-08-01

In the present study, pure iron/copper composite metal cladding was deposited onto carbon steel by tungsten inert gas welding. The study focused on interfacial morphological, microstructural, and mechanical analyses of the composite cladding layers. Iron liquid-solid-phase zones were formed at copper/steel and iron interfaces because of the melting of the steel substrate and iron. Iron concentrated in the copper cladding layer was observed to exhibit belt, globule, and dendrite morphologies. The appearance of iron-rich globules indicated the occurrence of liquid phase separation (LPS) prior to solidification, and iron-rich dendrites crystallized without the occurrence of LPS. The maximum microhardness of the iron/steel interface was lower than that of the copper/steel interface because of the diffusion of elemental carbon. All samples fractured in the cladding layers. Because of a relatively lower strength of the copper layer, a short plateau region appeared when shear movement was from copper to iron.

Effects of copper vapour on thermophysical properties of CO2-N2 plasma

NASA Astrophysics Data System (ADS)

Zhong, Linlin; Wang, Xiaohua; Rong, Mingzhe; Cressault, Yann

2016-10-01

CO2-N2 mixtures are often used as arc quenching medium (to replace SF6) in circuit breakers and shielding gas in arc welding. In such applications, copper vapour resulting from electrode surfaces can modify characteristics of plasmas. This paper therefore presents an investigation of the effects of copper on thermophysical properties of CO2-N2 plasma. The equilibrium compositions, thermodynamic properties (including mass density, specific enthalpy, and specific heat), transport coefficients (including electrical conductivity, viscosity, and thermal conductivity), and four kinds of combined diffusion coefficients due to composition gradients, applied electric fields, temperature gradients, and pressure gradients respectively, were calculated and discussed for CO2-N2 (mixing ratio 7:3) plasma contaminated by different proportions of copper vapour. The significant influences of copper were observed on all the properties of CO2-N2-Cu mixtures. The better ionization ability and larger molar mass of copper and larger collision integrals related to copper, should be responsible for such influences.

Effects of Electrical Current and External Stress on the Electromigration of Intermetallic Compounds Between the Flip-Chip Solder and Copper Substrate

NASA Astrophysics Data System (ADS)

Chen, Wei-Jhen; Lee, Yue-Lin; Wu, Ti-Yuan; Chen, Tzu-Ching; Hsu, Chih-Hui; Lin, Ming-Tzer

2018-01-01

This study investigated the effects of electric current and external stress on electromigration of intermetallic compounds (IMC) between solder and copper substrate. Different samples were tested under three different sets of conditions: (1) thermal aging only, (2) thermal aging with electric current ,where resistivity changes were measured using four-point probe measurements, (3) thermal aging with electric current and external stress provided using a four-point bending apparatus. The micro-structural changes in the samples were observed. The results were closely examined; particularly the coupling effect of electric current and external stress to elucidate the electromigration mechanism, as well as the formation of IMC in the samples. For thermal-aging-only samples, the IMC growth mechanism was controlled by grain boundary diffusion. Meanwhile, for thermal aging and applied electric current samples, the IMC growth mechanism was dominated by volume diffusion and interface reaction. Lastly, the IMC growth mechanism in the electric current and external stress group was dominated by grain boundary diffusion with grain growth. The results reveal that the external stress/strain and electric current play a significant role in the electromigration of copper-tin IMC. The samples exposed to tensile stress have reduced electromigration, while those subjected under compressive stress have enhanced electromigration.

Development of Biomarkers for Chronic Beryllium Disease in Mice

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

Gordon, Terry

2013-01-25

Beryllium is a strategic metal, indispensable for national defense programs in aerospace, telecommunications, electronics, and weaponry. Exposure to beryllium is an extensively documented occupational hazard that causes irreversible, debilitating granulomatous lung disease in as much as 3 - 5% of exposed workers. Mechanistic research on beryllium exposure-disease relationships has been severely limited by a general lack of a sufficient CBD animal model. We have now developed and tested an animal model which can be used for dissecting dose-response relationships and pathogenic mechanisms and for testing new diagnostic and treatment paradigms. We have created 3 strains of transgenic mice in whichmore » the human antigen-presenting moiety, HLA-DP, was inserted into the mouse genome. Each mouse strain contains HLA-DPB1 alleles that confer different magnitude of risk for chronic beryllium disease (CBD): HLA-DPB1*0401 (odds ratio = 0.2), HLA-DPB1*0201 (odds ratio = 15), HLA-DPB1*1701 (odds ratio = 240). Our preliminary work has demonstrated that the *1701 allele, as predicted by human studies, results in the greatest degree of sensitization in a mouse ear swelling test. We have also completed dose-response experiments examining beryllium-induced lung granulomas and identified susceptible and resistant inbred strains of mice (without the human transgenes) as well as quantitative trait loci that may contain gene(s) that modify the immune response to beryllium. In this grant application, we propose to use the transgenic and normal inbred strains of mice to identify biomarkers for the progression of beryllium sensitization and CBD. To achieve this goal, we propose to compare the sensitivity and accuracy of the lymphocyte proliferation test (blood and bronchoalveolar lavage fluid) with the ELISPOT test in the three HLA-DP transgenic mice strains throughout a 6 month treatment with beryllium particles. Because of the availability of high-throughput proteomics, we will also identify changes in potential protein biomarkers in beryllium-treated mice. We will correlate these findings with the ability of the transgenic mice to develop a beryllium-specific adaptive immune response in blood and bronchoalveolar lavage (BAL) fluid. We will also determine whether beryllium-responsive CD4+ T cells in blood and BAL correlate with the onset of granuloma formation. Thus, we will provide the scientific community with biomarkers of sensitization and disease progression for CBD. These biomarkers will serve as critical tools for development of improved industrial hygiene and therapeutic interventions.« less

Stabilization of the Thermal Decomposition of Poly(Propylene Carbonate) Through Copper Ion Incorporation and Use in Self-Patterning

NASA Astrophysics Data System (ADS)

Spencer, Todd J.; Chen, Yu-Chun; Saha, Rajarshi; Kohl, Paul A.

2011-06-01

Incorporation of copper ions into poly(propylene carbonate) (PPC) films cast from γ-butyrolactone (GBL), trichloroethylene (TCE) or methylene chloride (MeCl) solutions containing a photo-acid generator is shown to stabilize the PPC from thermal decomposition. Copper ions were introduced into the PPC mixtures by bringing the polymer mixture into contact with copper metal. The metal was oxidized and dissolved into the PPC mixture. The dissolved copper interferes with the decomposition mechanism of PPC, raising its decomposition temperature. Thermogravimetric analysis shows that copper ions make PPC more stable by up to 50°C. Spectroscopic analysis indicates that copper ions may stabilize terminal carboxylic acid groups, inhibiting PPC decomposition. The change in thermal stability based on PPC exposure to patterned copper substrates was used to provide a self-aligned patterning method for PPC on copper traces without the need for an additional photopatterning registration step. Thermal decomposition of PPC is then used to create air isolation regions around the copper traces. The spatial resolution of the self-patterning PPC process is limited by the lateral diffusion of the copper ions within the PPC. The concentration profiles of copper within the PPC, patterning resolution, and temperature effects on the PPC decomposition have been studied.

M3FT-16OR020202112 - Report on viability of hydrothermal corrosion resistant SiC/SiC Joint development

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

Katoh, Yutai; Koyanagi, Takaaki; Kiggans Jr, James O.

2016-06-30

Hydrothermal corrosion of four types of the silicon carbide (SiC) to SiC plate joints were investigated under PWR and BWR relevant chemical conditions without irradiation. The joints were formed by metal diffusion bonding using molybdenum or titanium interlayer, reaction sintering using Ti-Si-C system, and SiC nanopowder sintering. Most of the formed joints withstood the corrosion tests for five weeks. The recession of the SiC substrates was limited. Based on the recession rate of the bonding layers, it was concluded that all the joints except for the molybdenum diffusion bond are promising under the reducing activity environments. The SiC nanopowder sinteredmore » joint was the most corrosion tolerant under the oxidizing activity environment among the four joints.« less

Influence of clay on the adsorption of heavy metals like copper and cadmium on chitosan.

PubMed

Prakash, Nagan; Latha, Srinivasan; Sudha, Persu N; Renganathan, N Gopalan

2013-02-01

The influence of clay on the adsorption of heavy metals like copper and cadmium on chitosan from simulated industrial wastewater is evaluated. Chitosan-clay blend with ratio of (1:1), (1:2), and (2:1) have been prepared, and these were used as membranes to remove copper and cadmium ions from synthetic industrial wastewater. The chemical parameters for quantities of adsorption of heavy metal contamination have been done, and the kinetics of adsorption has also been carried out. Clay provides enough absorbable sites to overcome mass transfer limitations. The number of absorbable sites for cadmium is more compared to copper, and thus the rate of recovery of cadmium is faster than copper, and the percentage removal of cadmium is more than copper at all times on clay over nylon 6. This difference indicates the influence of clay in the adsorption of heavy metals in comparison to synthetic polymer nylon 6. Rate constant for first-order kinetics of adsorption, k (1), for copper and cadmium is less than that of clay, which clearly indicates that clay, which is a natural polymer, is more kinetically favored compared to synthetic polymer. The difference in the intraparticle diffusion in both the natural and synthetic polymer is not much, and it suggests that the particle diffusion mechanism is the same in both cases. Copper and cadmium recovery is parallel at all times. The percentage of removal of copper increased with an increase in pH from 3 to 5. In the case of cadmium containing wastewater, the maximum removal of metal occurred at pH 5. The uptake amount of Cu(2+) ions on chitosan increased rapidly with increasing the contact time from 0 to 360 min and then reaches equilibrium after 360 min, and the equilibrium constant for copper and cadmium ions are more or less the same for the adsorption reaction. There are more adsorption sites for cadmium in the presence of clay and mass transfer limitation is avoided without resorting to rotation, which is the highlight of the present work. And more so, this is pronounced in the case of natural polymer compared to synthetic polymer.

High-performance coaxial EPR cavity for investigations at elevated temperatures and pressures

NASA Astrophysics Data System (ADS)

Goldberg, Ira B.; McKinney, Ted M.

1984-07-01

A microwave cavity suitable for heating a sample to temperatures above 800 °C within 15 s at gas pressures above 17.5 MPa is reported. The cavity is coaxial and operates in the TE011 mode at frequencies between 9 and 10 GHz. The heating element is constructed of nickel-chromium (i.e., Chromel) wire. It consists of two concentric helices wound in opposite senses (directions) and connected in series so as to minimize the magnetic field generated by the heater current. The heater is potted in magnesium oxide-phosphate ceramic and placed inside of a cylinder made from 50-μm copper foil which provides uniform temperature distribution and shields the heater from the microwave field. This assembly then serves as the heating element and the coaxial conductor of the cavity. The diameter of the coaxial heater assembly is approximately 7 mm. The sample is confined by a cylindrical quartz cuvette which surrounds the coaxial conductor. Sample thicknesses of 0.2 to 1.0 mm can be used. Heating from room temperature to 800 °C requires between 15 and 20 s. Operating pressures up to 17 MPa have been used, although the structural design limit of the brass or beryllium copper walls is greater than 22 MPa. Modulation coils are placed in recessed areas of the cavity walls and covered with a thin layer of copper. Cooling water flows through channels cut into the walls to maintain constant microwave parameters. Q factors of 8000 -12 000 can be obtained depending on the sample.

Some problems of brazing technology for the divertor plate manufacturing

NASA Astrophysics Data System (ADS)

Prokofiev, Yu. G.; Barabash, V. R.; Khorunov, V. F.; Maksimova, S. V.; Gervash, A. A.; Fabritsiev, S. A.; Vinokurov, V. F.

1992-09-01

Among the different design options of the ITER reactor divertor, the joints of the carbon-based materials and molybdenum alloys and joints of tungsten and copper alloys are considered. High-temperature brazing is one of the most promising joining methods for the plasma facing and heat sink materials. The use of brazing for creation of W-Cu and graphite-Mo joints are given here. In addition, the investigation results of microstructure, microhardness and mechanical properties of the joints are presented. For W-Cu samples an influence of the neutron irradiation on the joining strength was studied.

Electromigration in solder joints and solder lines

NASA Astrophysics Data System (ADS)

Gan, H.; Choi, W. J.; Xu, G.; Tu, K. N.

2002-06-01

Electromigration may affect the reliability of flip-chip solder joints. Eutectic solder is a two-phase alloy, so its electromigration behavior is different from that in aluminum or copper interconnects. In addition, a flipchip solder joint has a built-in currentcrowding configuration to enhance electromigration failure. To better understand electromigration in SnPb and lead-free solder alloys, the authors prepared solder lines in v-grooves etched on Si (001). This article discusses the results of those tests and compares the electromigration failure modes of eutectic SnPb and SnAgCu flip-chip solder joints along with the mean-timeto-failure.

Evaluation of cooling concepts and specimen geometries for high heat flux tests on neutron irradiated divertor elements

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

Linke, J.; Bolt. H.; Breitbach, G.

1994-12-31

To assess the lifetime and the long term heat removal capabilities of plasma facing components in future thermonuclear fusion reactors such as ITER, neutron irradiation and subsequent high heat flux tests will be most essential. The effect of neutron damage will be simulated in material test reactors (such as the HFR-Petten) in a fission neutron environment. To investigate the heat loads during normal and off-normal operation scenarios a 60 kW electron beam test stand (Juelich Divertor Test Facility in Hot Cells, JUDITH) has been installed in a hot cell which can be operated by remote handling techniques. In this facilitymore » inertially cooled test coupons can be handled as well as small actively cooled divertor mock-ups. A special clamping mechanism for small test coupons (25 mm x 25 mm x 35 mm) with an integrated coolant channel within a copper or TZM heat sink has been developed and tested in an electron beam test bed. This method is an attractive alternative to costly large scale tests on complete divertor modules. The temperature and stress fields in individual CFC or beryllium tiles brazed to metallic heat sink (e.g. copper or TZM) can be investigated before and after neutron irradiation with moderate efforts.« less

The Cryogenic Properties of Several Aluminum-Beryllium Alloys and a Beryllium Oxide Material

NASA Technical Reports Server (NTRS)

Gamwell, Wayne R.; McGill, Preston B.

2003-01-01

Performance related mechanical properties for two aluminum-beryllium (Al-Be) alloys and one beryllium-oxide (BeO) material were developed at cryogenic temperatures. Basic mechanical properties (Le., ultimate tensile strength, yield strength, percent elongation, and elastic modulus were obtained for the aluminum-beryllium alloy, AlBeMetl62 at cryogenic [-195.5"C (-320 F) and -252.8"C (-423"F)I temperatures. Basic mechanical properties for the Be0 material were obtained at cyrogenic [- 252.8"C (-423"F)] temperatures. Fracture properties were obtained for the investment cast alloy Beralcast 363 at cryogenic [-252.8"C (-423"F)] temperatures. The AlBeMetl62 material was extruded, the Be0 material was hot isostatic pressing (HIP) consolidated, and the Beralcast 363 material was investment cast.

Thin-film diffusion brazing of titanium alloys

NASA Technical Reports Server (NTRS)

Mikus, E. B.

1972-01-01

A thin film diffusion brazing technique for joining titanium alloys by use of a Cu intermediate is described. The method has been characterized in terms of static and dynamic mechanical properties on Ti-6Al-4V alloy. These include tensile, fracture toughness, stress corrosion, shear, corrosion fatigue, mechanical fatigue and acoustic fatigue. Most of the properties of titanium joints formed by thin film diffusion brazing are equal or exceed base metal properties. The advantages of thin film diffusion brazing over solid state diffusion bonding and brazing with conventional braze alloys are discussed. The producibility advantages of this process over others provide the potential for producing high efficiency joints in structural components of titanium alloys for the minimum cost.

Joint estimation of phase and phase diffusion for quantum metrology.

PubMed

Vidrighin, Mihai D; Donati, Gaia; Genoni, Marco G; Jin, Xian-Min; Kolthammer, W Steven; Kim, M S; Datta, Animesh; Barbieri, Marco; Walmsley, Ian A

2014-04-14

Phase estimation, at the heart of many quantum metrology and communication schemes, can be strongly affected by noise, whose amplitude may not be known, or might be subject to drift. Here we investigate the joint estimation of a phase shift and the amplitude of phase diffusion at the quantum limit. For several relevant instances, this multiparameter estimation problem can be effectively reshaped as a two-dimensional Hilbert space model, encompassing the description of an interferometer phase probed with relevant quantum states--split single-photons, coherent states or N00N states. For these cases, we obtain a trade-off bound on the statistical variances for the joint estimation of phase and phase diffusion, as well as optimum measurement schemes. We use this bound to quantify the effectiveness of an actual experimental set-up for joint parameter estimation for polarimetry. We conclude by discussing the form of the trade-off relations for more general states and measurements.

Microstructure and mechanical properties of diffusion bonded W/steel joint using V/Ni composite interlayer

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

Liu, W.S.; Cai, Q.S., E-mail: cai2009pm@163.com; Ma, Y.Z.

2013-12-15

Diffusion bonding between W and steel using V/Ni composite interlayer was carried out in vacuum at 1050 °C and 10 MPa for 1 h. The microstructural examination and mechanical property evaluation of the joints show that the bonding of W to steel was successful. No intermetallic compound was observed at the steel/Ni and V/W interfaces for the joints bonded. The electron probe microanalysis and X-ray diffraction analysis revealed that Ni{sub 3}V, Ni{sub 2}V, Ni{sub 2}V{sub 3} and NiV{sub 3} were formed at the Ni/V interface. The tensile strength of about 362 MPa was obtained for as-bonded W/steel joint and themore » failure occurred at W near the V/W interface. The nano-indentation test across the joining interfaces demonstrated the effect of solid solution strengthening and intermetallic compound formation in the diffusion zone. - Highlights: • Diffusion bonding of W to steel was realized using V/Ni composite interlayer. • The interfacial microstructure of the joint was clarified. • Several V–Ni intermetallic compounds were formed in the interface region. • The application of V/Ni composite interlayer improved the joining quality.« less

Reliability analysis of different structure parameters of PCBA under drop impact

NASA Astrophysics Data System (ADS)

Liu, P. S.; Fan, G. M.; Liu, Y. H.

2018-03-01

The establishing process of PCBA is modelled by finite element analysis software ABAQUS. Firstly, introduce the Input-G method and the fatigue life under drop impact are introduced and the mechanism of the solder joint failure in the process of drop is analysed. The main reason of solder joint failure is that the PCB component is suffering repeated tension and compression stress during the drop impact. Finally, the equivalent stress and peel stress of different solder joint and plate-level components under different impact acceleration are also analysed. The results show that the reliability of tin-silver copper joint is better than that of tin- lead solder joint, and the fatigue life of solder joint expectancy decrease as the impact pulse amplitude increases.

Accelerator mass spectrometry detection of beryllium ions in the antigen processing and presentation pathway

DOE PAGES

Tooker, Brian C.; Brindley, Stephen M.; Chiarappa-Zucca, Marina L.; ...

2014-06-16

We report that exposure to small amounts of beryllium (Be) can result in beryllium sensitization and progression to Chronic Beryllium Disease (CBD). In CBD, beryllium is presented to Be-responsive T-cells by professional antigen-presenting cells (APC). This presentation drives T-cell proliferation and pro-inflammatory cytokine (IL-2, TNFα, and IFNγ) production and leads to granuloma formation. The mechanism by which beryllium enters an APC and is processed to become part of the beryllium antigen complex has not yet been elucidated. Developing techniques for beryllium detection with enough sensitivity has presented a barrier to further investigation. The objective of this study was to demonstratemore » that Accelerator Mass Spectrometry (AMS) is sensitive enough to quantify the amount of beryllium presented by APC to stimulate Be-responsive T-cells. To achieve this goal, APC - which may or may not stimulate Be-responsive T-cells - were cultured with Be-ferritin. Then, by utilizing AMS, the amount of beryllium processed for presentation was determined. Further, IFNγ intracellular cytokine assays were performed to demonstrate that Be-ferritin (at levels used in the experiments) could stimulate Be-responsive T-cells when presented by an APC of the correct HLA type (HLA-DP0201). The results indicated that Be-responsive T-cells expressed IFNγ only when APC with the correct HLA type were able to process Be for presentation. Utilizing AMS, we determined that APC with HLA-DP0201 had membrane fractions containing 0.17-0.59 ng Be and APC with HLA-DP0401 had membrane fractions bearing 0.40-0.45 ng Be. However, HLA-DP0401 APC had 20-times more Be associated with the whole cells (57.68-61.12 ng) then HLA-DP0201 APC (0.90-3.49 ng). As these findings demonstrate, AMS detection of picogram levels of Be processed by APC is possible. Further, regardless of form, Be requires processing by APC to successfully stimulate Be-responsive T-cells to generate IFNγ.« less

The association of sacroiliac joint bridging with other enthesopathies in the human body.

PubMed

Dar, Gali; Peleg, Smadar; Masharawi, Youssef; Steinberg, Nili; Rothschild, Bruce M; Hershkovitz, Israel

2007-05-01

A descriptive study of the association between sacroiliac joint (extra-articular) bridging and other enthesopathies. To examine the relationship between sacroiliac joint bridging with other entheseal reaction sites in the skeleton, and its prognostic value in spinal diseases. Sacroiliac joint bridging is considered a hallmark of spinal diseases (e.g., ankylosing spondylitis). Nevertheless, its association with other enthesopathies has never been quantified and analyzed. A total of 289 human male skeletons with sacroiliac joint bridging and 127 without (of similar demographic structure) were evaluated for the presence of entheseal ossification, cartilaginous calcification, and other axial skeleton joint fusion (a total of 18 anatomic sites). The presence of diffuse idiopathic skeletal hyperostosis and spondyloarthropathy was also recorded. Sacroiliac joint bridging was strongly associated with entheseal reactions in other parts of the body. Of the sacroiliac joint bridging group, 24.91% had diffuse idiopathic skeletal hyperostosis, and 8.05% had spondyloarthropathy. The presence of sacroiliac joint bridging indicates an intensive general entheseal process in the skeleton.

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

Samavatian, Majid, E-mail: m.samavatian@srbiau.ac.ir; Halvaee, Ayoub; Amadeh, Ahmad Ali

Joining mechanism of Ti/Al dissimilar alloys was studied during liquid state diffusion bonding process using Cu/Sn/Cu interlayer at 510 °C under vacuum of 7.5 × 10{sup −5} Torr for various bonding times. The microstructure and compositional changes in the joint zone were analyzed by scanning electron microscopy equipped with energy dispersive spectroscopy and X-ray diffraction. Microhardness and shear strength tests were also applied to study the mechanical properties of the joints. It was found that with an increase in bonding time, the elements of interlayer diffused into the parent metals and formed various intermetallic compounds at the interface. Diffusion processmore » led to the isothermal solidification and the bonding evolution in the joint zone. The results from mechanical tests showed that microhardness and shear strength values have a straight relation with bonding time so that the maximum shear strength of joint was obtained for a bond made with 60 min bonding time. - Highlights: • Liquid state diffusion bonding of Al2024 to Ti–6Al–4V was performed successfully. • Diffusion of the elements caused the formation of various intermetallics at the interface. • Microhardness and shear strength values have a straight relation with bonding time. • The maximum shear strength reached to 36 MPa in 60 min bonding time.« less

Fracture toughness of hot-pressed beryllium

NASA Technical Reports Server (NTRS)

Lemon, D. D.; Brown, W. F., Jr.

1985-01-01

This paper presents the results of an investigation into the fracture toughness, sustained-load flaw growth, and fatigue-crack propagation resistance of S200E hot-pressed beryllium at room temperature. It also reviews the literature pertaining to the influence of various factors on the fracture toughness of hot-pressed beryllium determined using fatigue-cracked specimens.

Process for synthesis of beryllium chloride dietherate

DOEpatents

Bergeron, Charles; Bullard, John E.; Morgan, Evan

1991-01-01

A low temperature method of producing beryllium chloride dietherate through the addition of hydrogen chloride gas to a mixture of beryllium metal in ether in a reaction vessel is described. A reflux condenser provides an exit for hydrogen produced form the reaction. A distillation condenser later replaces the reflux condenser for purifying the resultant product.

76 FR 19768 - Agency Information Collection Activities; Submission to OMB for Review and Approval; Comment...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-04-08

... Activities; Submission to OMB for Review and Approval; Comment Request; NESHAP for Beryllium Rocket Motor... . Title: NESHAP for Beryllium Rocket Motor Fuel Firing (Renewal). ICR Numbers: EPA ICR Number 1125.06, OMB...: Owners or operators of beryllium rocket motor fuel firing facilities. Estimated Number of Respondents: 1...

20 CFR 30.5 - What are the definitions used in this part?

Code of Federal Regulations, 2014 CFR

2014-04-01

... beryllium employee (see § 30.205), a covered employee with cancer (see § 30.210(a)), a covered employee with... have had established chronic beryllium disease, cancer, or chronic silicosis. (z) Eligible surviving... means, under Part B of the Act, a covered beryllium illness, cancer sustained in the performance of duty...

Structure and mechanical properties of foils made of nanocrystalline beryllium

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

Zhigalina, O. M., E-mail: zhigal@ns.crys.ras.ru; Semenov, A. A.; Zabrodin, A. V.

2016-07-15

The phase composition and structural features of (45–90)-μm-thick foils obtained from nanocrystalline beryllium during multistep thermomechanical treatment have been established using electron microscopy, electron diffraction, electron backscattering diffraction, and energy-dispersive analysis. This treatment is shown to lead to the formation of a structure with micrometer- and submicrometer-sized grains. The minimum average size of beryllium grains is 352 nm. The inclusions of beryllium oxide (BeO) of different modifications with tetragonal (sp. gr. P4{sub 2}/mnm) and hexagonal (sp. gr. P6{sub 3}/mmc) lattices are partly ground during deformation to a size smaller than 100 nm and are located along beryllium grain boundaries inmore » their volume, significantly hindering migration during treatment. The revealed structural features of foils with submicrometer-sized crystallites provide the thermal stability of their structural state. Beryllium with this structure is a promising material for X-ray instrument engineering and for the production of ultrathin (less than 10 μm) vacuum-dense foils with very high physicomechanical characteristics.« 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.

Ionic Diffusion in Cu6PS5Br Studied by 63Cu NMR

NASA Astrophysics Data System (ADS)

Ohki, H.; Harazono, K.; Erata, T.; Tasaki, A.; Ikeda, R.

1993-10-01

Applying 63Cu NMR technique, we observed exchange between the nonequivalent copper sites in crystalline Cu6PS5Br, known as a member of the mineral "argyrodite". Below 200 K, where the motion of the copper (I) ion is slow, we could distinguish several nonequivalent copper sites. On increasing the temperature, the chemical exchange between the nonequivalent cation sites was seen on the 63Cu NMR spectra. We could determine the activation energy for this motion to be 35 kJ mol-1 , in good agreement with the published ionic conductivity.

Modification of surface layers of copper under the action of the volumetric discharge initiated by an avalanche electron beam in nitrogen and CO2 at atmospheric pressure

NASA Astrophysics Data System (ADS)

Shulepov, M. A.; Akhmadeev, Yu. Kh.; Tarasenko, V. F.; Kolubaeva, Yu. A.; Krysina, O. V.; Kostyrya, I. D.

2011-05-01

The results of experimental investigations of the action of the volumetric discharge initiated by an avalanche electron beam on the surface of copper specimens are presented. The volumetric (diffuse) discharge in nitrogen and CO2 at atmospheric pressure was initiated by applying high voltage pulses of nanosecond duration to a tubular foil cathode. It has been found that the treatment of a copper surface by this type of discharge increases the hardness of the surface layer due to oxidation.

On the use of flat tile armour in high heat flux components

NASA Astrophysics Data System (ADS)

Merola, M.; Vieider, G.

1998-10-01

The possibility to have a flat tile geometry for those high heat flux components subjected to a convective heat flux (namely the divertor dump target, lower vertical target, and the limiter) has been investigated. Because of the glancing incidence of the power load, if an armour tile falls off an extremely high heat flux hits the leading edge of the adjacent tile. As a result a rapid temperature increase occurs in the armour-heat sink joint. The heat flux to the water coolant also increases rapidly up to a factor of 1.7 and 2.3 for a beryllium and CFC armour, respectively, thus causing possible critical heat flux problems. Thermal stresses in the armour-heat sink joint double in less than 0.4 s and triplicate after 1 s thus leading to a possible cascade failure. Therefore the use of a flat tile geometry for these components does not seem to be appropriate. In this case a monoblock geometry gives a much more robust solution.

Auger electron spectroscopy and Rutherford backscattering studies of copper in 2024-T3 aluminum following electrochemical anodization in phosphoric acid

NASA Astrophysics Data System (ADS)

Solomon, J. S.

1981-05-01

The effects of the electrochemical anodization of dioxidized 2024-T3 aluminum on copper were characterized by Auger electron spectroscopy and Rutherford backscattering. Anodization was performed in phosphoric acid at constant potential. Data is presented which shows that constant potential anodization of 2024-T3 is more efficient than aluminum in terms of oxide growth rates for short anodization times. However the maximum anodic oxide thickness achievable on the alloy is less than the pure metal. Copper is shown to be enriched at the oxide metal interface because of its diffusion from the bulk during anodization. The presence of copper at the oxide-metal interface is shown to affect oxide morphology.

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

Tooker, Brian C.; Brindley, Stephen M.; Chiarappa-Zucca, Marina L.

We report that exposure to small amounts of beryllium (Be) can result in beryllium sensitization and progression to Chronic Beryllium Disease (CBD). In CBD, beryllium is presented to Be-responsive T-cells by professional antigen-presenting cells (APC). This presentation drives T-cell proliferation and pro-inflammatory cytokine (IL-2, TNFα, and IFNγ) production and leads to granuloma formation. The mechanism by which beryllium enters an APC and is processed to become part of the beryllium antigen complex has not yet been elucidated. Developing techniques for beryllium detection with enough sensitivity has presented a barrier to further investigation. The objective of this study was to demonstratemore » that Accelerator Mass Spectrometry (AMS) is sensitive enough to quantify the amount of beryllium presented by APC to stimulate Be-responsive T-cells. To achieve this goal, APC - which may or may not stimulate Be-responsive T-cells - were cultured with Be-ferritin. Then, by utilizing AMS, the amount of beryllium processed for presentation was determined. Further, IFNγ intracellular cytokine assays were performed to demonstrate that Be-ferritin (at levels used in the experiments) could stimulate Be-responsive T-cells when presented by an APC of the correct HLA type (HLA-DP0201). The results indicated that Be-responsive T-cells expressed IFNγ only when APC with the correct HLA type were able to process Be for presentation. Utilizing AMS, we determined that APC with HLA-DP0201 had membrane fractions containing 0.17-0.59 ng Be and APC with HLA-DP0401 had membrane fractions bearing 0.40-0.45 ng Be. However, HLA-DP0401 APC had 20-times more Be associated with the whole cells (57.68-61.12 ng) then HLA-DP0201 APC (0.90-3.49 ng). As these findings demonstrate, AMS detection of picogram levels of Be processed by APC is possible. Further, regardless of form, Be requires processing by APC to successfully stimulate Be-responsive T-cells to generate IFNγ.« less

Modelisation and distribution of neutron flux in radium-beryllium source (226Ra-Be)

NASA Astrophysics Data System (ADS)

Didi, Abdessamad; Dadouch, Ahmed; Jai, Otman

2017-09-01

Using the Monte Carlo N-Particle code (MCNP-6), to analyze the thermal, epithermal and fast neutron fluxes, of 3 millicuries of radium-beryllium, for determine the qualitative and quantitative of many materials, using method of neutron activation analysis. Radium-beryllium source of neutron is established to practical work and research in nuclear field. The main objective of this work was to enable us harness the profile flux of radium-beryllium irradiation, this theoretical study permits to discuss the design of the optimal irradiation and performance for increased the facility research and education of nuclear physics.

Infrared spectroscopic study of radiation-induced adsorption of n-hexane on a beryllium surface

NASA Astrophysics Data System (ADS)

Gadzhieva, N. N.

2017-07-01

Radiation-stimulated adsorption on a beryllium surface is studied by IR reflection-absorption spectroscopy. It is found that γ-irradiation at room temperature leads to the appearance of n-hexane adsorption centers on a beryllium surface according to molecular and dissociation mechanisms. The kinetics of n-hexane adsorption in a Be- n-hexane system is studied; activated dissociative chemisorption accompanied by formation of beryllium alkyls and surface hydrides is observed at absorbed doses 15 kGy ≤ Vγ ≤ 35 kGy. A possible mechanism of this process is suggested.

Analytical results and sample locality map of heavy-mineral-concentrate and rock samples from the Castle Peaks Wilderness Study Area (CDCA- 266), San Bernardino County, California

USGS Publications Warehouse

Adrian, B.M.; Frisken, J.G.; Malcolm, M.J.; Crock, J.G.

1986-01-01

The report presents water-quality and geohydrologic information for 106 public water-supply wells in Illinois. These wells were sampled during April to December 1984 as part of a pilot program to develop a ground-water observation network in the State. The pilot program was designed to sample single-aquifer wells from three major aquifer systems--(1) sand and gravel, both confined and unconfined; (2) Silurian dolomite; and (3) the Ironton-Galesville deep sandstone. Data are tabulated for water temperature, pH, specific conductance, oxidation-reduction potential, ammonia nitrogen, nitrate + nitrite nitrogen, phosphorus, silica, arsenic, lead, mercury, fluoride, chloride, sulfate, cyanide, phenols, selenium, residue on evaporation at 180 degrees Celsius, alkalinity, calcium, magnesium, sodium, potassium, barium, boron, beryllium, cadmium, chormium, copper, cobalt, iron, aluminum, manganese, nickel, silver, strontium, vanadium, zinc, and selected geohydrologic information.

Thermally induced spin rate ripple on spacecraft with long radial appendages

NASA Technical Reports Server (NTRS)

Fedor, J. V.

1983-01-01

A thermally induced spin rate ripple hypothesis is proposed to explain the spin rate anomaly observed on ISEE-B. It involves the two radial 14.5 meter beryllium copper tape ribbons going in and out of the spacecraft hub shadow. A thermal lag time constant is applied to the thermally induced ribbon displacements which perturb the spin rate. It is inferred that the averaged thermally induced ribbon displacements are coupled to the ribbon angular motion. A possible exponential build up of the inplane motion of the ribbon which in turn causes the spin rate ripple, ultimately limited by damping in the ribbon and spacecraft is shown. It is indicated that qualitative increase in the oscillation period and the thermal lag is fundamental for the period increase. found that numerical parameter values required to agree with in orbit initial exponential build up are reasonable; those required for the ripple period are somewhat extreme.

$$\\pi^0$$ Production with $K^-$ and $$\\pi^+$$ Beams at 530 GeV/c

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

Lanaro, Armando

1990-01-01

In thia theaia we report on measurements of inclusive neutral pion production at large transverse momenta (more » $$P_T$$) in collision of 530 GeV/c ($$\\sqrt{s}$$ = 31.5 GeV) $K^-$ and $$\\pi^+$$ beams with a copper and beryllium combined target. The $$\\pi^0$$ acceptance in center-of-mass rapidity is $$\\mid y \\mid$$ < 0.7, for $$P_T$$ values greater than 3.5 GeV/c (negative beam) and 4.25 GeV/c (positive beam). The data were taken using the large acceptance liquid argon calorimeter of the E706 spectrometer at Fermilab, and analyzed using the standard E706 reconstruction package. Ratios on $$\\pi^0$$ yields using $$\\pi^+, \\pi^-, K^-$$ and $p$ are presented. The results are used to examine issues of scaling in point-like hadronic collisions at high energies and large transverse momenta.« less

Beryllium disease

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

Not Available

1991-12-20

After two workers at the nuclear weapons plant at Oak Ridge National Laboratory in Tennessee were diagnosed earlier this year with chronic beryllium disease (CBD), a rare and sometimes fatal scarring of the lungs, the Department of Energy ordered up a 4-year probe. Now, part of that probe has begun - tests conducted by the Oak Ridge Associated Universities' Center for Epidemiological Research measuring beryllium sensitivity in 3,000 people who've been exposed to the metal's dust since Manhattan Project managers opened the Y-12 plant at Oak Ridge in 1943. Currently, 119 Y-12 employees process beryllium, which has a number ofmore » industrial uses, including rocket heat shields and nuclear weapon and electrical components. The disease often takes 20 to 25 years to develop, and the stricken employees haven't worked with beryllium for years. There is no cure for CBD, estimated to strike 2% of people exposed to the metal. Anti-inflammatory steroids alleviate such symptoms as a dry cough, weight loss, and fatigue. Like other lung-fibrosis diseases that are linked to lung cancer, some people suspect CBD might cause some lung cancer. While difficult to diagnose, about 900 cases of CBD have been reported since a Beryllium Case Registry was established in 1952. The Department of Energy (DOE) estimates that about 10,000 DOE employees and 800,000 people in private industry have worked with beryllium.« less

Diffusion paths formation for Cu + ions in superionic Cu 6PS 5I single crystals studied in terms of structural phase transition

NASA Astrophysics Data System (ADS)

Gągor, A.; Pietraszko, A.; Kaynts, D.

2005-11-01

In order to understand the structural transformations leading to high ionic conductivity of Cu + ions in Cu 6PS 5I argyrodite compound, the detailed structure analysis based on single-crystal X-ray diffraction has been performed. Below the phase transition at T=(144-169) K Cu 6PS 5I belongs to monoclinic, ferroelastic phase (space group Cc) with ordered copper sublattice. Above Tc delocalization of copper ions begins and crystal changes the symmetry to cubic superstructure with space group F-43 c ( a'=19.528 Å, z=32). Finally, above T1=274 K increasing disordering of the Cu + ions heightens the symmetry to F-43 m ( a=9.794 Å, z=4). In this work, the final structural model of two cubic phases is presented including the detailed temperature evolution of positions and site occupation factors of copper ions ( R1=0.0397 for F-43 c phase, and 0.0245 for F-43 m phase). Possible diffusion paths for the copper ions are represented by means of the atomic displacement factors and split model. The structural results coincide well with the previously reported non-Arrhenius behavior of conductivity and indicate significant change in conduction mechanism.

Adsorption kinetic and desorption studies of Cu2+ on Multi-Carboxylic-Functionalized Silica Gel

NASA Astrophysics Data System (ADS)

Li, Min; Meng, Xiaojing; Liu, Yushuang; Hu, Xinju; Liang, Xiuke

2018-01-01

In the present study, the adsorption behavior of copper (II) ion from aqueous solution onto multi-carboxylic-functionalized silica gel (SG-MCF) has been investigated in detail by means of batch and column experiments. Batch experiments were performed to evaluate the effects of contact time on adsorption capacity of copper (II) ion. The kinetic data were analyzed on the basis of the pseudo-first-order kinetic and the pseudo-second-order kinetic models and consequently, the pseudo-second-order kinetic can better describe the adsorption process than the pseudo-first-order kinetic model. And the adsorption mechanism of the process was studied by intra-particle and film diffusion, it was found out that the adsorption rate was governed primarily by film diffusion to the adsorption onto the SG-MCF. In addition, column experiments were conducted to assess the effects initial inlet concentration and the flow rate on breakthrough time and adsorption capacity ascertaining the practical applicability of the adsorbent. The results suggest that the total amount of adsorbed copper (II) ion increased with declined flow rate and increased the inlet concentration. The adsorption-desorption experiment confirmed that adsorption capacity of copper (II) ion didn’t present an obvious decrease after five cycles.

Studies of Be migration in the JET tokamak using AMS with 10Be marker

NASA Astrophysics Data System (ADS)

Bykov, I.; Bergsåker, H.; Possnert, G.; Zhou, Y.; Heinola, K.; Pettersson, J.; Conroy, S.; Likonen, J.; Petersson, P.; Widdowson, A.

2016-03-01

The JET tokamak is operated with beryllium limiter tiles in the main chamber and tungsten coated carbon fiber composite tiles and solid W tiles in the divertor. One important issue is how wall materials are migrating during plasma operation. To study beryllium redistribution in the main chamber and in the divertor, a 10Be enriched limiter tile was installed prior to plasma operations in 2011-2012. Methods to take surface samples have been developed, an abrasive method for bulk Be tiles in the main chamber, which permits reuse of the tiles, and leaching with hot HCl to remove all Be deposited at W coated surfaces in the divertor. Quantitative analysis of the total amount of Be in cm2 sized samples was made with inductively coupled plasma atomic emission spectroscopy (ICP-AES). The 10Be/9Be ratio in the samples was measured with accelerator mass spectrometry (AMS). The experimental setup and methods are described in detail, including sample preparation, measures to eliminate contributions in AMS from the 10B isobar, possible activation due to plasma generated neutrons and effects of diffusive isotope mixing. For the first time marker concentrations are measured in the divertor deposits. They are in the range 0.4-1.2% of the source concentration, with moderate poloidal variation.

Two tandem queues with general renewal input. 2: Asymptotic expansions for the diffusion model

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

Knessl, C.; Tier, C.

1999-10-01

In Part 1 the authors formulated and solved a diffusion model for two tandem queues with exponential servers and general renewal arrivals. They thus obtained the easy traffic diffusion approximation to the steady state joint queue length distribution for this network. Here they study asymptotic and numerical properties of the diffusion approximation. In particular, analytical expressions are obtained for the tail probabilities. Both the joint distribution of the two queues and the marginal distribution of the second queue are considered. They also give numerical illustrations of how this marginal is affected by changes in the arrival and service processes.

The Cryogenic Tensile Properties of an Extruded Aluminum-Beryllium Alloy

NASA Technical Reports Server (NTRS)

Gamwell, W. R.

2002-01-01

Basic mechanical properties; i.e., ultimate tensile strength, yield strength, percent elongation, and elastic modulus, were obtained for the aluminum-beryllium alloy, AlBeMet162, at cryogenic (-195.5 C (-320 F) and -252.8 C (-423 F)) temperatures. The material evaluated was purchased to the requirements of SAE-AMS7912, "Aluminum-Beryllium Alloy, Extrusions."

303-K Storage Facility closure plan. Revision 2

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

Not Available

1993-12-15

Recyclable scrap uranium with zircaloy-2 and copper silicon alloy, uranium-titanium alloy, beryllium/zircaloy-2 alloy, and zircaloy-2 chips and fines were secured in concrete billets (7.5-gallon containers) in the 303-K Storage Facility, located in the 300 Area. The beryllium/zircaloy-2 alloy and zircaloy-2 chips and fines are designated as mixed waste with the characteristic of ignitability. The concretion process reduced the ignitability of the fines and chips for safe storage and shipment. This process has been discontinued and the 303-K Storage Facility is now undergoing closure as defined in the Resource Conservation and Recovery Act (RCRA) of 1976 and the Washington Administrative Codemore » (WAC) Dangerous Waste Regulations, WAC 173-303-040. This closure plan presents a description of the 303-K Storage Facility, the history of materials and waste managed, and the procedures that will be followed to close the 303-K Storage Facility. The 303-K Storage Facility is located within the 300-FF-3 (source) and 300-FF-5 (groundwater) operable units, as designated in the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement) (Ecology et al. 1992). Contamination in the operable units 300-FF-3 and 300-FF-5 is scheduled to be addressed through the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980 remedial action process. Therefore, all soil remedial action at the 304 Facility will be conducted as part of the CERCLA remedial action of operable units 300-FF-3 and 300-FF-5.« less

Divacancy complexes induced by Cu diffusion in Zn-doped GaAs

NASA Astrophysics Data System (ADS)

Elsayed, M.; Krause-Rehberg, R.; Korff, B.; Ratschinski, I.; Leipner, H. S.

2013-08-01

Positron annihilation spectroscopy was applied to investigate the nature and thermal behavior of defects induced by Cu diffusion in Zn-doped p-type GaAs crystals. Cu atoms were intentionally introduced in the GaAs lattice through thermally activated diffusion from a thin Cu capping layer at 1100 °C under defined arsenic vapor pressure. During isochronal annealing of the obtained Cu-diffused GaAs in the temperature range of 450-850 K, vacancy clusters were found to form, grow and finally disappear. We found that annealing at 650 K triggers the formation of divacancies, whereas further increasing in the annealing temperature up to 750 K leads to the formation of divacancy-copper complexes. The observations suggest that the formation of these vacancy-like defects in GaAs is related to the out-diffusion of Cu. Two kinds of acceptors are detected with a concentration of about 1016 - 1017 cm-3, negative ions and arsenic vacancy copper complexes. Transmission electron microscopy showed the presence of voids and Cu precipitates which are not observed by positron measurements. The positron binding energy to shallow traps is estimated using the positron trapping model. Coincidence Doppler broadening spectroscopy showed the presence of Cu in the immediate vicinity of the detected vacancies. Theoretical calculations suggested that the detected defect is VGaVAs-2CuGa.

Assessment of Lead and Beryllium deposition and adsorption to exposed stream channel sediments

NASA Astrophysics Data System (ADS)

Pawlowski, E.; Karwan, D. L.

2016-12-01

The fallout radionuclides Beryllium-7 and Lead-210 have been shown to be effective sediment tracers that readily bind to particles. The adsorption capacity has primarily been assessed in marine and coastal environments with an important assumption being the radionuclides' uniform spatial distribution as fallout from the atmosphere. This neglects localized storm events that may mine stratospheric reserves creating variable distributions. To test this assumption atmospheric deposition is collected at the University of Minnesota St. Paul Campus weather station during individual storm events and subsequently analyzed for Beryllium-7 and Lead-210. This provides further insight into continental effects on radionuclide deposition. The study of Beryllium-7 and Lead-210 adsorption in marine and coastal environments has provided valuable insights into the processes that influence the element's binding to particles but research has been limited in freshwater river environments. These environments have greater variation in pH, iron oxide content, and dissolved organic carbon (DOC) levels which have been shown to influence the adsorption of Beryllium and Lead in marine settings. This research assesses the adsorption of Beryllium and Lead to river sediments collected from in-channel deposits by utilizing batch experiments that mimic the stream conditions from which the deposits were collected. Soils were collected from Difficult Run, VA, and the West Swan River, MN. Agitating the soils in a controlled solution of known background electrolyte and pH while varying the level of iron oxides and DOC in step provides a better understanding of the sorption of Lead and Beryllium under the conditions found within freshwater streams. Pairing the partitioning of Lead and Beryllium with their inputs to streams via depositional processes, from this study and others, allows for their assessment as possible sediment tracers and age-dating tools within the respective watersheds.

Proton irradiation effects on beryllium – A macroscopic assessment

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

Simos, Nikolaos; Elbakhshwan, Mohamed; Zhong, Zhong

Beryllium, due to its excellent neutron multiplication and moderation properties, in conjunction with its good thermal properties, is under consideration for use as plasma facing material in fusion reactors and as a very effective neutron reflector in fission reactors. While it is characterized by unique combination of structural, chemical, atomic number, and neutron absorption cross section it suffers, however, from irradiation generated transmutation gases such as helium and tritium which exhibit low solubility leading to supersaturation of the Be matrix and tend to precipitate into bubbles that coalesce and induce swelling and embrittlement thus degrading the metal and limiting itsmore » lifetime. Utilization of beryllium as a pion production low-Z target in high power proton accelerators has been sought both for its low Z and good thermal properties in an effort to mitigate thermos-mechanical shock that is expected to be induced under the multi-MW power demand. To assess irradiation-induced changes in the thermal and mechanical properties of Beryllium, a study focusing on proton irradiation damage effects has been undertaken using 200 MeV protons from the Brookhaven National Laboratory Linac and followed by a multi-faceted post-irradiation analysis that included the thermal and volumetric stability of irradiated beryllium, the stress-strain behavior and its ductility loss as a function of proton fluence and the effects of proton irradiation on the microstructure using synchrotron X-ray diffraction. The mimicking of high temperature irradiation of Beryllium via high temperature annealing schemes has been conducted as part of the post-irradiation study. This study focuses on the thermal stability and mechanical property changes of the proton irradiated beryllium and presents results of the macroscopic property changes of Beryllium deduced from thermal and mechanical tests.« less

Proton irradiation effects on beryllium – A macroscopic assessment

DOE PAGES

Simos, Nikolaos; Elbakhshwan, Mohamed; Zhong, Zhong; ...

2016-07-01

Beryllium, due to its excellent neutron multiplication and moderation properties, in conjunction with its good thermal properties, is under consideration for use as plasma facing material in fusion reactors and as a very effective neutron reflector in fission reactors. While it is characterized by unique combination of structural, chemical, atomic number, and neutron absorption cross section it suffers, however, from irradiation generated transmutation gases such as helium and tritium which exhibit low solubility leading to supersaturation of the Be matrix and tend to precipitate into bubbles that coalesce and induce swelling and embrittlement thus degrading the metal and limiting itsmore » lifetime. Utilization of beryllium as a pion production low-Z target in high power proton accelerators has been sought both for its low Z and good thermal properties in an effort to mitigate thermos-mechanical shock that is expected to be induced under the multi-MW power demand. To assess irradiation-induced changes in the thermal and mechanical properties of Beryllium, a study focusing on proton irradiation damage effects has been undertaken using 200 MeV protons from the Brookhaven National Laboratory Linac and followed by a multi-faceted post-irradiation analysis that included the thermal and volumetric stability of irradiated beryllium, the stress-strain behavior and its ductility loss as a function of proton fluence and the effects of proton irradiation on the microstructure using synchrotron X-ray diffraction. The mimicking of high temperature irradiation of Beryllium via high temperature annealing schemes has been conducted as part of the post-irradiation study. This study focuses on the thermal stability and mechanical property changes of the proton irradiated beryllium and presents results of the macroscopic property changes of Beryllium deduced from thermal and mechanical tests.« less

Proton irradiation effects on beryllium - A macroscopic assessment

NASA Astrophysics Data System (ADS)

Simos, Nikolaos; Elbakhshwan, Mohamed; Zhong, Zhong; Camino, Fernando

2016-10-01

Beryllium, due to its excellent neutron multiplication and moderation properties, in conjunction with its good thermal properties, is under consideration for use as plasma facing material in fusion reactors and as a very effective neutron reflector in fission reactors. While it is characterized by unique combination of structural, chemical, atomic number, and neutron absorption cross section it suffers, however, from irradiation generated transmutation gases such as helium and tritium which exhibit low solubility leading to supersaturation of the Be matrix and tend to precipitate into bubbles that coalesce and induce swelling and embrittlement thus degrading the metal and limiting its lifetime. Utilization of beryllium as a pion production low-Z target in high power proton accelerators has been sought both for its low Z and good thermal properties in an effort to mitigate thermos-mechanical shock that is expected to be induced under the multi-MW power demand. To assess irradiation-induced changes in the thermal and mechanical properties of Beryllium, a study focusing on proton irradiation damage effects has been undertaken using 200 MeV protons from the Brookhaven National Laboratory Linac and followed by a multi-faceted post-irradiation analysis that included the thermal and volumetric stability of irradiated beryllium, the stress-strain behavior and its ductility loss as a function of proton fluence and the effects of proton irradiation on the microstructure using synchrotron X-ray diffraction. The mimicking of high temperature irradiation of Beryllium via high temperature annealing schemes has been conducted as part of the post-irradiation study. This paper focuses on the thermal stability and mechanical property changes of the proton irradiated beryllium and presents results of the macroscopic property changes of Beryllium deduced from thermal and mechanical tests.

Investigation of LRS dependence on the retention of HRS in CBRAM

NASA Astrophysics Data System (ADS)

Xu, Xiaoxin; Lv, Hangbing; Liu, Hongtao; Luo, Qing; Gong, Tiancheng; Wang, Ming; Wang, Guoming; Zhang, Meiyun; Li, Yang; Liu, Qi; Long, Shibing; Liu, Ming

2015-02-01

The insufficient retention prevents the resistive random access memory from intended application, such as code storage, FPGA, encryption, and others. The retention characteristics of high resistance state (HRS) switching from different low resistance state (LRS) were investigated in a 1-kb array with one transistor and one resistor configuration. The HRS degradation was found strongly dependent on the LRS: the lower the resistance of the LRS ( R LRS) is, the worse HRS retention will be. According to the quantum point contact model, the HRS corresponds to a tiny tunnel gap or neck bridge with atomic size in the filament. The degradation of HRS is due to the filling or widening of the neck point by the diffusion of copper species from the residual filament. As the residual filament is stronger in case of the lower R LRS, the active area around the neck point for copper species diffusion is larger, resulting in higher diffusion probability and faster degradation of HRS during the temperature-accelerated retention measurement.

Influence of argon impurities on the elastic scattering of x-rays from imploding beryllium capsules

DOE PAGES

Saunders, A. M.; Chapman, D. A.; Kritcher, A. L.; ...

2018-03-01

Here, we investigate the effect of argon impurities on the elastic component of x-ray scattering spectra taken from directly driven beryllium capsule implosions at the OMEGA laser. The plasma conditions were obtained in a previous analysis [18] by fitting the inelastic scattering component. We show that the known argon impurity in the beryllium modifies the elastic scattering due to the larger number of bound electrons. We indeed find significant deviations in the elastic scattering from roughly 1 at.% argon contained in the beryllium. With knowledge of the argon impurity fraction, we use the elastic scattering component to determine the chargemore » state of the compressed beryllium, as the fits are rather insensitive to the argon charge state. Lastly, we discuss how doping small fractions of mid- or high-Z elements into low-Z materials could allow ionization balance studies in dense plasmas.« less

Beryllium Interactions in Molten Salts

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

G. S. Smolik; M. F. Simpson; P. J. Pinhero

Molten flibe (2LiF·BeF2) is a candidate as a cooling and tritium breeding media for future fusion power plants. Neutron interactions with the salt will produce tritium and release excess free fluorine ions. Beryllium metal has been demonstrated as an effective redox control agent to prevent free fluorine, or HF species, from reacting with structural metal components. The extent and rate of beryllium solubility in a pot design experiments to suppress continuously supplied hydrogen fluoride gas has been measured and modeled[ ]. This paper presents evidence of beryllium loss from specimens, a dependence of the loss upon bi-metal coupling, i.e., galvanicmore » effect, and the partitioning of the beryllium to the salt and container materials. Various posttest investigative methods, viz., scanning electron microscopy (SEM), Auger electron spectroscopy (AES) and x-ray photoelectron spectroscopy (XPS) were used to explore this behavior.« less

Beryllium-aluminum alloys for investment castings

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

Nachtrab, W.T.; Levoy, N.

1997-05-01

Beryllium-aluminum alloys containing greater than 60 wt % beryllium are very favorable materials for applications requiring light weight and high stiffness. However, when produced by traditional powder metallurgical methods, these alloys are expensive and have limited applications. To reduce the cost of making beryllium-aluminum components, Nuclear Metals Inc. (NMI) and Lockheed Martin Electronics and Missiles have recently developed a family of patented beryllium-aluminum alloys that can be investment cast. Designated Beralcast, the alloys can achieve substantial weight savings because of their high specific strength and stiffness. In some cases, weight has been reduced by up to 50% over aluminum investmentmore » casting. Beralcast is now being used to make thin wall precision investment castings for several advanced aerospace applications, such as the RAH-66 Comanche helicopter and F-22 jet fighter. This article discusses alloy compositions, properties, casting method, and the effects of cobalt additions on strength.« less

Influence of argon impurities on the elastic scattering of x-rays from imploding beryllium capsules

NASA Astrophysics Data System (ADS)

Saunders, A. M.; Chapman, D. A.; Kritcher, A. L.; Schoff, M.; Shuldberg, C.; Landen, O. L.; Glenzer, S. H.; Falcone, R. W.; Gericke, D. O.; Döppner, T.

2018-03-01

We investigate the effect of argon impurities on the elastic component of x-ray scattering spectra taken from directly driven beryllium capsule implosions at the OMEGA laser. The plasma conditions were obtained in a previous analysis [18] by fitting the inelastic scattering component. We show that the known argon impurity in the beryllium modifies the elastic scattering due to the larger number of bound electrons. We indeed find significant deviations in the elastic scattering from roughly 1 at.% argon contained in the beryllium. With knowledge of the argon impurity fraction, we use the elastic scattering component to determine the charge state of the compressed beryllium, as the fits are rather insensitive to the argon charge state. Finally, we discuss how doping small fractions of mid- or high-Z elements into low-Z materials could allow ionization balance studies in dense plasmas.

Novel preparation of highly photocatalytically active copper chromite nanostructured material via a simple hydrothermal route

PubMed Central

Beshkar, Farshad; Zinatloo-Ajabshir, Sahar; Bagheri, Samira; Salavati-Niasari, Masoud

2017-01-01

Highly photocatalytically active copper chromite nanostructured material were prepared via a novel simple hydrothermal reaction between [Cu(en)2(H2O)2]Cl2 and [Cr(en)3]Cl3.3H2O at low temperature, without adding any pH regulator or external capping agent. The as-synthesized nanostructured copper chromite was analyzed by transmission electron microscopy (TEM), UV–vis diffuse reflectance spectroscopy, energy dispersive X-ray microanalysis (EDX), scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy. Results of the morphological investigation of the as-synthesized products illustrate that the shape and size of the copper chromite depended on the surfactant sort, reaction duration and temperature. Moreover, the photocatalytic behavior of as-obtained copper chromite was evaluated by photodegradation of acid blue 92 (anionic dye) as water pollutant. PMID:28582420

Discrete Cu(i) complexes for azide-alkyne annulations of small molecules inside mammalian cells.

PubMed

Miguel-Ávila, Joan; Tomás-Gamasa, María; Olmos, Andrea; Pérez, Pedro J; Mascareñas, José L

2018-02-21

The archetype reaction of "click" chemistry, namely, the copper-promoted azide-alkyne cycloaddition (CuAAC), has found an impressive number of applications in biological chemistry. However, methods for promoting intermolecular annulations of exogenous, small azides and alkynes in the complex interior of mammalian cells, are essentially unknown. Herein we demonstrate that isolated, well-defined copper(i)-tris(triazolyl) complexes featuring designed ligands can readily enter mammalian cells and promote intracellular CuAAC annulations of small, freely diffusible molecules. In addition to simplifying protocols and avoiding the addition of "non-innocent" reductants, the use of these premade copper complexes leads to more efficient processes than with the alternative, in situ made copper species prepared from Cu(ii) sources, tris(triazole) ligands and sodium ascorbate. Under the reaction conditions, the well-defined copper complexes exhibit very good cell penetration properties, and do not present significant toxicities.

IDM release behavior and surface characteristics of the novel Cu/IDM/LDPE nanocomposite for intrauterine device.

PubMed

Yang, Zhihong; Xie, Changsheng; Xiang, Hua; Feng, Jinqing; Xia, Xianping; Cai, Shuizhou

2009-03-01

Copper/indomethacin/low-density polyethylene (Cu/IDM/LDPE) nanocomposite was prepared as a novel material for intra-uterine device (IUD). IDM release profile of the nanocomposite was investigated by using spectrophotometer. The results show that IDM release rate of Cu/IDM/LDPE nanocomposite is higher in simulated uterine solution than that in methanol, confirming that the release process of IDM is dominated mainly by pore diffusion. The decrease in copper particle size and the increase in copper mass content all accelerate IDM release, indicating that IDM release rate can be adjusted by changing copper loading or copper particle size. The surface of the incubated nanocomposite was characterized by X-ray diffraction, scanning electron microscopy and energy dispersive X-ray microanalysis. A few deposits composed of P, Cl, Ca, Cu and O were observed on the nanocomposite surface, which may be related to the presence of IDM particles with large particle size.

What is the copper thin film thickness effect on thermal properties of NiTi/Cu bi-layer?

NASA Astrophysics Data System (ADS)

Fazeli, Sara; Vahedpour, Morteza; Khatiboleslam Sadrnezhaad, Sayed

2017-02-01

Molecular dynamics (MD) simulation was used to study of thermal properties of NiTi/Cu. Embedded atom method (EAM) potentials for describing of inter-atomic interaction and Nose-Hoover thermostat and barostat are employed. The melting of the bi-layers was considered by studying the temperature dependence of the cohesive energy and mean square displacement. To highlight the differences between bi-layers with various copper layer thickness, the effect of copper film thickness on thermal properties containing the cohesive energy, melting point, isobaric heat capacity and latent heat of fusion was estimated. The results show that thermal properties of bi-layer systems are higher than that of their corresponding of pure NiTi. But, these properties of bi-layer systems approximately are independent of copper film thicknesses. The mean square displacement (MSD) results show that, the diffusion coefficients enhance upon increasing of copper film thickness in a linear performance.

One hundred fold increase in current carrying capacity in a carbon nanotube–copper composite

PubMed Central

Subramaniam, Chandramouli; Yamada, Takeo; Kobashi, Kazufumi; Sekiguchi, Atsuko; Futaba, Don N.; Yumura, Motoo; Hata, Kenji

2013-01-01

Increased portability, versatility and ubiquity of electronics devices are a result of their progressive miniaturization, requiring current flow through narrow channels. Present-day devices operate close to the maximum current-carrying-capacity (that is, ampacity) of conductors (such as copper and gold), leading to decreased lifetime and performance, creating demand for new conductors with higher ampacity. Ampacity represents the maximum current-carrying capacity of the object that depends both on the structure and material. Here we report a carbon nanotube–copper composite exhibiting similar conductivity (2.3–4.7 × 105 S cm−1) as copper (5.8 × 105 S cm−1), but with a 100-times higher ampacity (6 × 108 A cm−2). Vacuum experiments demonstrate that carbon nanotubes suppress the primary failure pathways in copper as observed by the increased copper diffusion activation energy (∼2.0 eV) in carbon nanotube–copper composite, explaining its higher ampacity. This is the only material with both high conductivity and high ampacity, making it uniquely suited for applications in microscale electronics and inverters. PMID:23877359

One hundred fold increase in current carrying capacity in a carbon nanotube-copper composite

NASA Astrophysics Data System (ADS)

Subramaniam, Chandramouli; Yamada, Takeo; Kobashi, Kazufumi; Sekiguchi, Atsuko; Futaba, Don N.; Yumura, Motoo; Hata, Kenji

2013-07-01

Increased portability, versatility and ubiquity of electronics devices are a result of their progressive miniaturization, requiring current flow through narrow channels. Present-day devices operate close to the maximum current-carrying-capacity (that is, ampacity) of conductors (such as copper and gold), leading to decreased lifetime and performance, creating demand for new conductors with higher ampacity. Ampacity represents the maximum current-carrying capacity of the object that depends both on the structure and material. Here we report a carbon nanotube-copper composite exhibiting similar conductivity (2.3-4.7 × 105Scm-1) as copper (5.8 × 105Scm-1), but with a 100-times higher ampacity (6 × 108Acm-2). Vacuum experiments demonstrate that carbon nanotubes suppress the primary failure pathways in copper as observed by the increased copper diffusion activation energy (~2.0eV) in carbon nanotube-copper composite, explaining its higher ampacity. This is the only material with both high conductivity and high ampacity, making it uniquely suited for applications in microscale electronics and inverters.

20 CFR 30.207 - How does a claimant prove a diagnosis of a beryllium disease covered under Part B?

Code of Federal Regulations, 2010 CFR

2010-04-01

... beryllium disease covered under Part B? 30.207 Section 30.207 Employees' Benefits OFFICE OF WORKERS... disease covered under Part B? (a) Written medical documentation is required in all cases to prove that the... lavage cells. (c) Chronic beryllium disease is established in the following manner: (1) For diagnoses on...

20 CFR 30.207 - How does a claimant prove a diagnosis of a beryllium disease covered under Part B?

Code of Federal Regulations, 2011 CFR

2011-04-01

... beryllium disease covered under Part B? 30.207 Section 30.207 Employees' Benefits OFFICE OF WORKERS... disease covered under Part B? (a) Written medical documentation is required in all cases to prove that the... lavage cells. (c) Chronic beryllium disease is established in the following manner: (1) For diagnoses on...

20 CFR 30.207 - How does a claimant prove a diagnosis of a beryllium disease covered under Part B?

Code of Federal Regulations, 2013 CFR

2013-04-01

... beryllium disease covered under Part B? 30.207 Section 30.207 Employees' Benefits OFFICE OF WORKERS... disease covered under Part B? (a) Written medical documentation is required in all cases to prove that the... lavage cells. (c) Chronic beryllium disease is established in the following manner: (1) For diagnoses on...

20 CFR 30.207 - How does a claimant prove a diagnosis of a beryllium disease covered under Part B?

Code of Federal Regulations, 2014 CFR

2014-04-01

... beryllium disease covered under Part B? 30.207 Section 30.207 Employees' Benefits OFFICE OF WORKERS... disease covered under Part B? (a) Written medical documentation is required in all cases to prove that the... lavage cells. (c) Chronic beryllium disease is established in the following manner: (1) For diagnoses on...

20 CFR 30.207 - How does a claimant prove a diagnosis of a beryllium disease covered under Part B?

Code of Federal Regulations, 2012 CFR

2012-04-01

... beryllium disease covered under Part B? 30.207 Section 30.207 Employees' Benefits OFFICE OF WORKERS... disease covered under Part B? (a) Written medical documentation is required in all cases to prove that the... lavage cells. (c) Chronic beryllium disease is established in the following manner: (1) For diagnoses on...

Beryllium-10 dating of the duration and retreat of the last pinedale glacial sequence

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

Gosse, J.C.; Klein, J.; Evenson, E.B.

Accurate terrestrial glacial chronologies are needed for comparison with the marine record to establish the dynamics of global climate change during transitions from glacial to interglacial regimes. Cosmogenic beryllium-10 measurements in the Wind River Range indicate that the last glacial maximum (marine oxygen isotope stage 2) was achieved there by 21,700 {+-} 700 beryllium-10 years and lasted 5900 years. Ages of a sequence of recessional moraines and striated bedrock surfaces show that the initial deglaciation was rapid and that the entire glacial system retreated 33 kilometers to the cirque basin by 12,100 {+-} 500 beryllium-10 years.

PREPARATION OF REFRACTORY OXIDE CRYSTALS

DOEpatents

Grimes, W.R.; Shaffer, J.H.; Watson, G.M.

1962-11-13

A method is given for preparing uranium dioxide, thorium oxide, and beryllium oxide in the form of enlarged individual crystals. The surface of a fused alkali metal halide melt containing dissolved uranium, thorium, or beryllium values is contacted with a water-vapor-bearing inert gas stream at a rate of 5 to 10 cubic centimeters per minute per square centimeter of melt surface area. Growth of individual crystals is obtained by prolonged contact. Beryllium oxide-coated uranium dioxide crystals are prepared by disposing uranium dioxide crystals 5 to 20 microns in diameter in a beryllium-containing melt and contacting the melt with a water-vapor-bearing inert gas stream in the same manner. (AEC)

Illness Absences Among Beryllium Sensitized Workers

PubMed Central

Watkins, Janice P.; Ellis, Elizabeth D.; Girardi, David J.; Cragle, Donna L.

2014-01-01

Objectives. This study examined absence rates among US Department of Energy workers who had beryllium sensitization (BeS) or were diagnosed with chronic beryllium disease (CBD) compared with those of other workers. Methods. We used the lymphocyte proliferation test to determine beryllium sensitivity. In addition, we applied multivariable logistic regression to compare absences from 2002 to 2011 between workers with BeS or CBD to those without, and survival analysis to compare time to first absence by beryllium sensitization status. Finally, we examined beryllium status by occupational group. Results. Fewer than 3% of the 19 305 workers were BeS, and workers with BeS or CBD had more total absences (odds ratio [OR] = 1.31; 95% confidence interval [CI] = 1.18, 1.46) and respiratory absences (OR = 1.51; 95% CI = 1.24, 1.84) than did other workers. Time to first absence for all causes and for respiratory conditions occurred earlier for workers with BeS or CBD than for other workers. Line operators and crafts personnel were at increased risk for BeS or CBD. Conclusions. Although not considered “diseased,” workers with BeS have higher absenteeism compared with nonsensitized workers. PMID:25211750

Containerless processing of beryllium

NASA Technical Reports Server (NTRS)

Wouch, G.; Keith, G. H.; Frost, R. T.; Pinto, N. P.

1977-01-01

Melting and solidification of a beryllium alloy containing 1.5% BeO by weight in the weightless environment of space has produced cast beryllium with a relatively uniform dispersion of BeO throughout. Examination of the cast material shows that it is coarse grained, although the BeO is not heavily agglomerated in the flight specimen. Ground based comparison experiments show extreme agglomeration and segregation of BeO, resulting in large zones which are practically free of the oxide. Several postulated hypotheses for the failure to grain refine the beryllium are formulated. These are: (1) spherodization of the BeO particles during specimen preparation and during the molten phase of the experiment; (2) loss of nucleation potency through aging in the molten phase; and (3) inability of BeO to act as a grain refiner for beryllium. Further investigation with non spherodized particles and shorter dwell times molten may delineate which of these hypotheses are valid. The results of this flight experiment indicate that the weightless environment of space is an important asset in conducting research to find grain refiners for beryllium and other metals for which cast dispersions of grain refining agents cannot be prepared terrestrially due to gravitationally driven settling and agglomeration.

Chronic beryllium disease: Diagnosis and management

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

Rossman, M.D.

1996-10-01

Chronic beryllium disease is predominantly a pulmonary granulomatosis that was originally described in 1946. Symptoms usually include dyspnea and cough. Fever, anorexia, and weight loss are common. Skin lesions are the most common extrathoracic manifestation. Granulomatous hepatitis, hypercalcemia, and kidney stones can also occur. Radiographic and physiologic abnormalities are similar to those in sarcoidosis. While traditionally the pathologic changes included granulomas and cellular interstitial changes, the hallmark of the disease today is the well-formed granuloma. Immunologic studies have demonstrated a cell-mediated response to beryllium that is due to an accumulation of CD4{sup +} T cells at the site of diseasemore » activity. Diagnosis depends on the demonstration of pathologic changes (i.e., granuloma) and evidence that the granuloma was caused by a hypersensitivity to beryllium (i.e., positive lung proliferative response to beryllium). Using these criteria, the diagnosis of chronic beryllium disease can now be made before the onset of clinical symptoms. Whether, with early diagnosis, the natural course of this condition will be the same as when it was traditionally diagnosed is not known. Currently, corticosteroids are used to treat patients with significant symptoms or evidence of progressive disease. 21 refs.« less

A Report on the Validation of Beryllium Strength Models

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

Armstrong, Derek Elswick

2016-02-05

This report discusses work on validating beryllium strength models with flyer plate and Taylor rod experimental data. Strength models are calibrated with Hopkinson bar and quasi-static data. The Hopkinson bar data for beryllium provides strain rates up to about 4000 per second. A limitation of the Hopkinson bar data for beryllium is that it only provides information on strain up to about 0.15. The lack of high strain data at high strain rates makes it difficult to distinguish between various strength model settings. The PTW model has been calibrated many different times over the last 12 years. The lack ofmore » high strain data for high strain rates has resulted in these calibrated PTW models for beryllium exhibiting significantly different behavior when extrapolated to high strain. For beryllium, the α parameter of PTW has recently been calibrated to high precision shear modulus data. In the past the α value for beryllium was set based on expert judgment. The new α value for beryllium was used in a calibration of the beryllium PTW model by Sky Sjue. The calibration by Sjue used EOS table information to model the temperature dependence of the heat capacity. Also, the calibration by Sjue used EOS table information to model the density changes of the beryllium sample during the Hopkinson bar and quasi-static experiments. In this paper, the calibrated PTW model by Sjue is compared against experimental data and other strength models. The other strength models being considered are a PTW model calibrated by Shuh- Rong Chen and a Steinberg-Guinan type model by John Pedicini. The three strength models are used in a comparison against flyer plate and Taylor rod data. The results show that the Chen PTW model provides better agreement to this data. The Chen PTW model settings have been previously adjusted to provide a better fit to flyer plate data, whereas the Sjue PTW model has not been changed based on flyer plate data. However, the Sjue model provides a reasonable fit to flyer plate and Taylor rod data, and also gives a better match to recently analyzed Z-machine data which has a strain of about 0.35 and a strain rate of 3e5 s -1.« less

Migration of Beryllium via Multiple Exposure Pathways among Work Processes in Four Different Facilities.

PubMed

Armstrong, Jenna L; Day, Gregory A; Park, Ji Young; Stefaniak, Aleksandr B; Stanton, Marcia L; Deubner, David C; Kent, Michael S; Schuler, Christine R; Virji, M Abbas

2014-01-01

Inhalation of beryllium is associated with the development of sensitization; however, dermal exposure may also be important. The primary aim of this study was to elucidate relationships among exposure pathways in four different manufacturing and finishing facilities. Secondary aims were to identify jobs with increased levels of beryllium in air, on skin, and on surfaces; identify potential discrepancies in exposure pathways, and determine if these are related to jobs with previously identified risk. Beryllium was measured in air, on cotton gloves, and on work surfaces. Summary statistics were calculated and correlations among all three measurement types were examined at the facility and job level. Exposure ranking strategies were used to identify jobs with higher exposures. The highest air, glove, and surface measurements were observed in beryllium metal production and beryllium oxide ceramics manufacturing jobs that involved hot processes and handling powders. Two finishing and distribution facilities that handle solid alloy products had lower exposures than the primary production facilities, and there were differences observed among jobs. For all facilities combined, strong correlations were found between air-surface (rp ≥ 0.77), glove-surface (rp ≥ 0.76), and air-glove measurements (rp ≥ 0.69). In jobs where higher risk of beryllium sensitization or disease has been reported, exposure levels for all three measurement types were higher than in jobs with lower risk, though they were not the highest. Some jobs with low air concentrations had higher levels of beryllium on glove and surface wipe samples, suggesting a need to further evaluate the causes of the discrepant levels. Although such correlations provide insight on where beryllium is located throughout the workplace, they cannot identify the direction of the pathways between air, surface, or skin. Ranking strategies helped to identify jobs with the highest combined air, glove, and/or surface exposures. All previously identified high-risk jobs had high air concentrations, dermal mass loading, or both, and none had low dermal and air. We have found that both pathways are relevant. [Supplementary materials are available for this article. Go to the publisher's online edition of Journal of Occupational and Environmental Hygiene for the following free supplemental resource: a file describing the forms of beryllium materials encountered during production and characteristics of the aerosols by process areas.].

The Interaction of Polycrystalline Copper Films with Dilute Aqueous Solutions of Cupric Chloride

DTIC Science & Technology

1989-10-01

to interconnect semiconductor devices and other computer components Electronic circuits are mass / produced to obtain poduct uniformity and lowestx...so one needs to determine what if any pH change is produced by this extraneous oxide film growth. Thus, in order to determine any interference which...diffusion type; bulk diffusion rates would lie between 10 - 1 3 and 6x10-12mol.h- 1cm-2 mixed grain -13 boundary and bulk diffusion would lie between 6x10

Effect of Intermetallic on Electromigration and Atomic Diffusion in Cu/SnAg3.0Cu0.5/Cu Joints: Experimental and First-Principles Study

NASA Astrophysics Data System (ADS)

Zhou, Wei; Liu, Lijuan; Li, Baoling; Wu, Ping

2009-06-01

Electromigration phenomena in a one-dimensional Cu/SnAg3.0Cu0.5/Cu joint were investigated with current stressing. The special effect of intermetallic compound (IMC) layers on the formation of serious electromigration damage induced by nonuniform current density distribution was discussed based on experimental results. Meanwhile, hillocks were observed both at the anode and near the cathode of the joint, and they were described as the result of diffusion of atoms and compressive stress released along grain boundaries to the relatively free surface. Moreover, the diffusion behavior of Cu at the cathode was analyzed with the electromigration equation, and the stability of Ag atoms in the solder during electromigration was evaluated with a first-principles method.

Solid-state-laser-rod holder

DOEpatents

Gettemy, D.J.; Barnes, N.P.; Griggs, J.E.

1981-08-11

The disclosure relates to a solid state laser rod holder comprising Invar, copper tubing, and epoxy joints. Materials and coefficients of expansion of the components of the holder combine with the rod to produce a joint which will give before the rod itself will. The rod may be lased at about 70 to 80/sup 0/K and returned from such a temperature to room temperature repeatedly without its or the holder's destruction.

Experimental Study of Solder/Copper Interface Failure Under Varying Strain Rates

DTIC Science & Technology

2011-03-01

Factors Affecting Solder Joint Reliability Gu et al. [1] determined that during the life cycle of electronic assemblies, approximately 55 percent of...related to vibration and shock, with the remaining percentage associated with changes in 2 humidity. Research conducted by Ross et al. [2] adds...that creep strain is the most important time-dependent factor affecting the reliability of solder joints in electronic equipment. 2. Effects of

Intermetallic layers in temperature controlled Friction Stir Welding of dissimilar Al-Cu-joints

NASA Astrophysics Data System (ADS)

Marstatt, R.; Krutzlinger, M.; Luderschmid, J.; Constanzi, G.; Mueller, J. F. J.; Haider, F.; Zaeh, M. F.

2018-06-01

Friction Stir Welding (FSW) can be performed to join dissimilar metal combinations like aluminium and copper, which is of high interest in modern production of electrical applications. The amount of intermetallic phases in the weld seam is significantly reduced compared to traditional fusion welding technologies. Because the solidus temperature is typically not reached during FSW, the growth of intermetallic phases is impeded and the intermetallic layer thicknesses typically remains on the scale of a few hundred nanometres. These layers provide a substance-to-substance bond, which is the main joining mechanism. Latest research confirms that the layer formation is most likely driven by the heat input during processing. Hence, the welding temperature is the key to achieve high quality joints. In this study, aluminium and copper sheets were welded in lap joint configuration using temperature-controlled FSW. An advanced in-tool measurement set-up was used to determine precise temperature data. Scanning electron microscopy (SEM) was used to analyse metallurgical aspects (e.g. structure and composition of the intermetallic phases) of the joints. The results show a correlation between the welding temperature and the thickness of the intermetallic layer and its structure. The temperature control significantly improved the correlation compared to previous studies. This leads to an enhanced understanding of the dominating joining mechanisms.

Oxide nucleation on thin films of copper during in situ oxidation in an electron microscope

NASA Technical Reports Server (NTRS)

Heinemann, K.; Rao, D. B.; Douglass, D. L.

1975-01-01

Single-crystal copper thin films were oxidized at an isothermal temperature of 425 C and at an oxygen partial pressure of 0.005 torr. Specimens were prepared by epitaxial vapor deposition onto polished faces of rocksalt and were mounted in a hot stage inside the ultrahigh-vacuum chamber of a high-resolution electron microscope. An induction period of roughly 30 min was established which was independent of the film thickness but depended strongly on the oxygen partial pressure and to exposure to oxygen prior to oxidation. Neither stacking faults nor dislocations were found to be associated with the Cu2O nucleation sites. The experimental data, including results from oxygen dissolution experiments and from repetitive oxidation-reduction-oxidation sequences, fit well into the framework of an oxidation process involving the formation of a surface charge layer, oxygen saturation of the metal with formation of a supersaturated zone near the surface, and nucleation followed by surface diffusion of oxygen and bulk diffusion of copper for lateral and vertical oxide growth, respectively.

Diffusion barrier properties of single- and multilayered quasi-amorphous tantalum nitride thin films against copper penetration

NASA Astrophysics Data System (ADS)

Chen, G. S.; Chen, S. T.

2000-06-01

Tantalum-related thin films containing different amounts of nitrogen are sputter deposited at different argon-to-nitrogen flow rate ratios on (100) silicon substrates. Using x-ray diffractometry, transmission electron microscopy, composition and resistivity analyses, and bending-beam stress measurement technique, this work examines the impact of varying the nitrogen flow rate, particularly on the crystal structure, composition, resistivity, and residual intrinsic stress of the deposited Ta2N thin films. With an adequate amount of controlled, reactive nitrogen in the sputtering gas, thin films of the tantalum nitride of nominal formula Ta2N are predominantly amorphous and can exist over a range of nitrogen concentrations slightly deviated from stoichiometry. The single-layered quasi-amorphous Ta2N (a-Ta2N) thin films yield intrinsic compressive stresses in the range 3-5 GPa. In addition, the use of the 40-nm-thick a-Ta2N thin films with different nitrogen atomic concentrations (33% and 36%) and layering designs as diffusion barriers between silicon and copper are also evaluated. When subjected to high-temperature annealing, the single-layered a-Ta2N barrier layers degrade primarily by an amorphous-to-crystalline transition of the barrier layers. Crystallization of the single-layered stoichiometric a-Ta2N (Ta67N33) diffusion barriers occurs at temperatures as low as 450 °C. Doing so allows copper to preferentially penetrate through the grain boundaries or thermal-induced microcracks of the crystallized barriers and react with silicon, sequentially forming {111}-facetted pyramidal Cu3Si precipitates and TaSi2 Overdoping nitrogen into the amorphous matrix can dramatically increase the crystallization temperature to 600 °C. This temperature increase slows down the inward diffusion of copper and delays the formation of both silicides. The nitrogen overdoped Ta2N (Ta64N36) diffusion barriers can thus be significantly enhanced so as to yield a failure temperature 100 °C greater than that of the Ta67N33 diffusion barriers. Moreover, multilayered films, formed by alternately stacking the Ta67N33 and Ta64N36 layers with an optimized bilayer thickness (λ) of 10 nm, can dramatically reduce the intrinsic compressive stress to only 0.7 GPa and undergo high-temperature annealing without crystallization. Therefore, the Ta67N33/Ta64N36 multilayered films exhibit a much better barrier performance than the highly crystallization-resistant Ta64N36 single-layered films.

Demonstration and Validation of a Regenerated Cellulose Dialysis Membrane Diffusion Sampler for Monitoring Groundwater Quality and Remediation Progress at DoD Sites

DTIC Science & Technology

2007-02-01

years if kept refrigerated in its preservative solution of ethanol, sodium benzoate , and ethylene diamine tetra-acetic acid (EDTA). Alternatively... sodium bicarbonate solution, EDTA, and sodium azide solution to remove residual gylcerol, sulfide, cadmium, chromium, copper, iron, nickel, zinc, and lead...Magnesium Cadmium Nickel Potassium Chromium Selenium Sodium Copper Vanadium Aluminum Iron Zinc Arsenic Lead Antimony Manganese Anions (1-3 days

A Study of the Diffusion, Electrochemical Mobility and Removal of Dissolved Copper in a Saturated Porous Medium.

DTIC Science & Technology

1980-11-01

aqueous solutions : use of activity coefficients in transition-state models: Geochimica et Cosmochimica Acta, v...native state at 25°C at any activity level below 10+46.0 in an aqueous solution . Because such an activity level is impossible, sodium cannot be reduced...stoichiometric coefficients . It is necessary to calculqte the activity coefficients of dissolved copper in the test solutions in order to render an