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Effect of Au on the reliability of fine pitch surface mount solder joints
The effect of Au on the reliability of 0.65 mm pitch surface mount solder joints between plastic quad flat packs and Cu-Ni-Au FR-4 printed circuit boards was investigated. Cu-Ni-Au is a desirable printed circuit board finish for multi-chip modules or printed circuit boards that would otherwise require a selective Au finish, for example for edge connectors or wire bondable parts. However, Au is known to embrittle solder when it is present in sufficiently high concentrations, creating a concern that solder joint fatigue life in service will also be adversely affected. This paper reports the results of mechanical shock, mechanical vibration and thermal cycling testing of fine pitch solder joints containing varying amounts of Au. Tests were performed on as-soldered joints and on joints that had been heat-treated to evolve the microstructure toward equilibrium. The tests were designed to accelerate in-service conditions in a typical industrial environment. Under these conditions, the Au concentrations tested did not promote solder joint failures. Microstructural characterization of the distribution and morphology of the Au-, Ni-, and Cu-Sn intermetallics in the joint before and after accelerated testing was also performed. On the basis of these observations it is recommended that the Au concentration in solder joints …
Date:
May 1, 1991
Creator:
Glazer, J. (Hewlett-Packard Co., Palo Alto, CA (United States)); Kramer, P. & Morris, J.W. Jr. (Lawrence Berkeley Lab., CA (United States))
Object Type:
Article
System:
The UNT Digital Library
Revised GCFR safety program plan
This paper presents a summary of the recently revised gas-cooled fast breeder reactor (GCFR) safety program plan. The activities under this plan are organized to support six lines of protection (LOPs) for protection of the public from postulated GCFR accidents. Each LOP provides an independent, sequential, quantifiable risk barrier between the public and the radiological hazards associated with postulated GCFR accidents. To implement a quantitative risk-based approach in identifying the important technology requirements for each LOP, frequency and consequence-limiting goals are allocated to each. To ensure that all necessary tasks are covered to achieve these goals, the program plan is broken into a work breakdown structure (WBS). Finally, the means by which the plan is being implemented are discussed.
Date:
May 1, 1980
Creator:
Kelley, A. P.; Boyack, B. E. & Torri, A.
Object Type:
Article
System:
The UNT Digital Library
Geothermal Reservoir Well Stimulation Program: technology transfer
The following are included: review of available data from previous fracturing stimulation operations, stimulation process variables, fracturing fluid design, hydraulic fracture design, stimulation case histories, and selected bibliography. (MHR)
Date:
May 1, 1980
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Superconducting final focus for the SLAC Linear Collider
Triplets composed of superconducting quadrupoles have been built and installed as the final focusing element for the high-energy positron and electron beams of the SLAC Linear Collider. Special features include independent alignment to 100-micron tolerance inside a common cryostat; non-magnetic materials to allow operation inside the detector's solenoid field; a continuous-flow helium-only system using 50-meter-long flexible transfer lines; and complete operation of the system before installation. The mechanical design and cryogenic operation experience are presented.
Date:
May 1, 1992
Creator:
Ash, W.W.; Barrera, F.; Burgess, W.; Cook, K.; Cutler, H.; Ferrie, J. et al.
Object Type:
Article
System:
The UNT Digital Library
Diffusion estimation for small emissions. Preliminary report
A simplified approach is presented to the calculation of ground level concentrations of effluents from small industrial and fuel burning installations. It is intended to serve as a first approximation to a very complex process. Because each stack, building, and terrain configuration is different, actual ground concentrations may frequently differ from the values calculated here by a factor of two. Nonetheless, this procedure should be useful for determining whether ambient air quality standards are likely to be met, exceeded, or only marginally obtained. It also predicts the locations where the highest and most frequent ground concentrations are likely. Sampling at several such locations is very advisable, unless the predicted concentrations are quite low. In addition, consultation with a specialist in air pollution meteorology may be desirable, especially in marginal or unique situations. The procedures given here were designed especially for source heights of less than 100 m; some of the simplifications made are not valid for large emissions. In the few cases where more than arithmetic formulas are necessary, simple nomograms are provided.
Date:
May 1, 1973
Creator:
Briggs, G.A.
Object Type:
Report
System:
The UNT Digital Library
Material Buckling Measurements on Graphite-Uranium Systems at Hanford: A Summary Tabulation
Measurements of material bucklings for graphite uranium systems are summarized. A comprehensive listing and guide to the original data sources is provided. Complete information on physical and nuclear properties of the lattice and the geometry of the exponential assembly is included, along with some of the auxiliary data taken. The fuel sizes vary from 0.925 to 2.5 in. in diameter for five different fuel geometries. The lattice spacings vary from 4 3/16 to 15 in. Over 300 measurements of material buckling are included. (auth)
Date:
May 1, 1961
Creator:
Wood, D. E.
Object Type:
Report
System:
The UNT Digital Library
Gas turbine engines and transmissions for bus demonstration programs. Technical status report, 31 January 1980-30 April 1980
Activities related to the procurement and delivery of 11 gas turbine engines, 11 automatic transmissions, and software items such as cost reports, drawings and parts lists for the bus demonstration program are reported. (LCL)
Date:
May 1, 1980
Creator:
Nigro, D.N.
Object Type:
Report
System:
The UNT Digital Library
Alternative dipole magnets for ISABELLE
A dipole magnet, intended as a possible alternative for the ISABELLE main-ring magnet, was designed at LBL. Three layers of FNAL Doubler/Saver conductor were used. Two 1.3-m-long models were built and tested, both with and without an iron core, and in both helium I and helium II. The training behavior, cyclic energy loss, point of quench initiation, and quench velocity were determined. A central field of 6.5 tesla was obtained in He I (4.4 K), and 7.6 tesla in He II (1.8K).
Date:
May 1, 1982
Creator:
Taylor, C.; Althaus, R.; Caspi, S.; Gilbert, W.; Hassenzahl, W.; Meuser, R. et al.
Object Type:
Article
System:
The UNT Digital Library
Krakow Clean Fossil Fuels and Energy Efficiency Project
In Karkow, Poland almost half of the energy used for heating is supplied by local, solid-fuel-fired boilerhouses and home stoves. These facilities are referred to as the low emission sources'' and are primary contributors of particulates and hydrocarbon air pollution in the city and secondary contributors of sulfur dioxide and carbon monoxide. The Support of Eastern European Democracy Act of 1989 directed the US Department of Energy to undertake an equipment assessment project aimed at developing the capability within Poland to manufacture or modify industrial-scale combustion equipment to utilize fossil fuels cleanly. The Project is being conducted in a manner that can be generalized to all of Poland and uito the rest of Eastern Europe. The project plan includes three phases which have been developed around five specific subprojects. In Phase 1, technical and economic assessments will be made of pollution reduction options for the five subprojects. Phase 2 plans call for public meetings in the US and Poland for companies interested in forming joint ventures. Information will be available in these meetings to enable companies to identify markets and select potential partners that meet with their capabilities and interests. In Phase 3, DOE will issue a solicitation for Polish/American …
Date:
May 1, 1992
Creator:
Butcher, T.A.; Pierce, B.; Krajewski, R.; LaMontagne, J. & Kirchstetter, T.
Object Type:
Article
System:
The UNT Digital Library
HEAD-END TREATMENT OF LOW LEVEL WASTES PRIOR TO FOAM SEPARATION
Calcium-magnesium precipitation apparatus was used to reduce the concentrations of these elements in ORNL tap water, used as a substitute for waste water of low level of radioactivity, prior to strontium removal by foam separation. With and without alkali and flocculator chambers and with a stirred sludge of ratio height to diameter equal to 1/1 to ~4/1, use of 5 x 10/sup -3/ M each of NaOH and Na/sub 2/CO/sub 3/ and 2 ppm Fe/sup 3+/ reduced the dissolved Ca + Mg concentrations to 1 to 2 ppm as calcium. Simultaneously, a strontium DF of 20 to 200 was achieved, and, by adding Grundite clay in the proportion ~0.5 1b/ 1000 gal, a cesium DF of 10 to 40 was achieved. (auth)
Date:
May 29, 1962
Creator:
Schonfeld, E. & Davis, W. Jr.
Object Type:
Report
System:
The UNT Digital Library
CHEMICAL EFFECTS OF HIGH EXPLOSIVE SHOCK WAVES ON VARIOUS COMPOUNDS WHICH OCCUR IN THE GNOME CONTAINMENT MEDIUM
None
Date:
May 1, 1962
Creator:
Bond, W.D.
Object Type:
Report
System:
The UNT Digital Library
Evaluation of the gas production economics of the gas hydrate cyclic thermal injection model. [Cyclic thermal injection]
The objective of the work performed under this directive is to assess whether gas hydrates could potentially be technically and economically recoverable. The technical potential and economics of recovering gas from a representative hydrate reservoir will be established using the cyclic thermal injection model, HYDMOD, appropriately modified for this effort, integrated with economics model for gas production on the North Slope of Alaska, and in the deep offshore Atlantic. The results from this effort are presented in this document. In Section 1, the engineering cost and financial analysis model used in performing the economic analysis of gas production from hydrates -- the Hydrates Gas Economics Model (HGEM) -- is described. Section 2 contains a users guide for HGEM. In Section 3, a preliminary economic assessment of the gas production economics of the gas hydrate cyclic thermal injection model is presented. Section 4 contains a summary critique of existing hydrate gas recovery models. Finally, Section 5 summarizes the model modification made to HYDMOD, the cyclic thermal injection model for hydrate gas recovery, in order to perform this analysis.
Date:
May 1, 1985
Creator:
Kuuskraa, V.A.; Hammersheimb, E. & Sawyer, W.
Object Type:
Report
System:
The UNT Digital Library
High temperature recuperator tests. Final report
A demonstration and test program was conducted on a high temperature, two pass ceramic tube recuperator. Data pertaining to heat exchanger performance characteristics were collected and compared with calculated values. The effect of improved heat exchanger effectiveness on system fuel consumption was demonstrated. Changes in fuel flow as a function of combustion air preheat while maintaining a given heat load were demonstrated. The effects of excess air on fuel consumption with and without system recuperation were demonstrated. A preheat level of 1740/sup 0/F with a heat exchanger inlet of 2537/sup 0/F for a recuperator effectiveness of 68% was demonstrated. Comparison of test measurements and calculated heat balance and heat transfer characteristics indicated that the measured effects of recuperation and excess air levels on fuel consumption were close to theoretical values. A post-program examination of the recuperator indicted that no damage to the recuperator occurred that could not be alleviated by minor design modification. The modifications necessary to achieve 1800 to 2000/sup 0/F preheat with a ceramic tube recuperator of the type demonstrated were extrapolated from measurements made in this program. The same two pass approach demonstrated in this program can be used. The number of face tubes vs. pressure drop …
Date:
May 1, 1980
Creator:
Bjerklie, J. W. & Penty, R. A.
Object Type:
Report
System:
The UNT Digital Library
Optimization of a VISAR for measuring flyer-plate velocities
VISAR (Velocity Interferometer System for Any Reflector) is commonly used for measuring flyer-plate velocities up to 6 km/s. Flyer plates can travel as much as 1 mm, which is large compared to usual depth-of-focus requirements for VISARs. Flyer plates are explosively driven, or driven by some other very energetic means; as such, they must be tested in a chamber, which will contain the explosion. Routing the laser beam to the chamber and the signal beam to the VISAR can be done safely and easily in multi-mode optical fibers. We have optimized a fiber-coupled VISAR system for measuring flyer-plate velocities. This system given constant signal levels over the full travel of the flyer plate. Furthermore, the signal-collection efficiency is maximized, which allows use of a moderately sized laser. We also have optimized the VISAR cavity so it does not limit the system efficiency while giving a velocity sensitivity of about 1 km/s per fringe. 5 refs.
Date:
May 6, 1992
Creator:
Sweatt, W. C.; Crump, O. B., Jr. & Brigham, W. P.
Object Type:
Article
System:
The UNT Digital Library
Calculation and Measurement of the Transient Temperature in a Low- Enrichment UO$sub 2$ Fuel Rod During Large Power Excursions
The results of Spert I in-pile transient tests of a rodtype, low- enrichment UO/sub 2/ fuel element are presented. The tests were performed to investigate the possibility of damage to such long thermal-time-constant fuel rods when subjected to short-period power excursions, and to test the effectiveness of an instrumentation technique for measurement of UO/sub 2/ fuel temperatures within the rods. In an initial series of power excursion tests, in which the range of reactor periods was from approximately 1 sec to 7.5 msec, simultaneous measurements were made of the transient temperature at the center of the fuel rod and at the outer cladding surface. Fuel rod rupture occurred during the exponential rise of the 7.5-msec excursion. Similar short-period tests performed on a second fuel rod contain ing no internal thermocouples did not result in cladding failure, supporting the postulation that rupture of the first rod was caused by waterlogging of the UO/sub 2/ as a result of the cladding penetrations made for installation of the internal thermocouples. Calculations of the transient temperature distribution in the fuel rod were made, and the results are found to be in good agreement with the experimental data obtained on the central-UO/sub 2/ and cladding-surface …
Date:
May 18, 1962
Creator:
Houghtaling, J. E.; Quigley, T. M. & Spano, A. H.
Object Type:
Report
System:
The UNT Digital Library
Research on elementary particle physics: Task P, Studies in theory and phenomenology of elementary particles
Over the last year, work has focused on two areas: the phenomenology of quark-gluon differentiation in jets, and theoretical studies involving Dirac-like equations for various systems. Substantive progress has been made in both areas. A paper comparing details of the Lund and Herwig simulations for quark and gluon jets has been written and accepted by Physical Review D. A paper describing a new type of Dirac equation for the relativistic harmonic oscillator, and finding solutions thereof, has been written and submitted for publication.
Date:
May 1, 1992
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Numerical simulations of turbulent flow fields caused by spraying of water on large releases of hydrogen fluoride
The effectiveness of water sprays in absorbing HF releases was recently demonstrated in extended laboratory and field tests. In this paper, computer simulations are presented of the Hawk, Nevada Test Site, series of field tests. The model used, HFSPRAY, is a Eulerean/Lagrangian model which simulates the momentum, mass and energy interactions between a water spray and a turbulent plume of HF in air; the model can predict the flow velocities, temperature, water vapor, and HF concentration fields in two-dimensional large- geometries for spraying in any direction, (i.e., down-flow, inclined-down-flow, up-flow, and co-current horizontal flow). The model was validated against recent data on spraying of water on large releases of HF. 17 refs., 11 figs., 4 tabs.
Date:
May 1, 1991
Creator:
Fthenakis, V.M. (Brookhaven National Lab., Upton, NY (United States)) & Schatz, K.W. (Mobil Research and Development Corp., Princeton, NJ (United States))
Object Type:
Article
System:
The UNT Digital Library
Environmental impact report (draft)
The three projects as proposed by Pacific Gas and Electric Company and the environmental analysis of the projects are discussed. Sections on the natural and social environments of the proposed projects and their surrounding areas consist of descriptions of the setting, discussions of the adverse and beneficial consequences of the project, and potential mitigation measures to reduce the effects of adverse impacts. The Environmental Impact Report includes discussions of unavoidable adverse effects, irreversible changes, long-term and cumulative impacts, growth-inducing effects, and feasible alternatives to the project. (MHR)
Date:
May 1, 1980
Creator:
unknown
Object Type:
Book
System:
The UNT Digital Library
MAP3S precipitation chemistry network. Third periodic summary report, July 1978-December 1979
The MAP3S Precipitation Chemistry Network consists of eight collection sites in the northeastern United States. Precipitation event samples are collected by cooperating site operators, using specially developed sampling equipment. In this, the third periodic summary report, are listed field and concentration data for the period July 1, 1978 to December 31, 1979. Over three years' samples have been collected at most of the sites, which went into operation between September 1976 and October 1978. Samples are chemically analyzed at a central laboratory for 13 pollutant species. Weekly samples in addition to event samples were collected over a 1 1/2 year period at three sites. Analysis of one year's results indicates that there is little difference between the concentrations collected by the two methods in terms of seasonal precipitation-weighted means for all species except dissolved SO/sub 2/. Event samples tend to average about 25% higher in SO/sub 2/ than weekly samples.
Date:
May 1, 1980
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Residential and commercial space heating and cooling with possible greenhouse operation; Baca Grande development, San Luis Valley, Colorado. Final report
A feasibility study was performed to evaluate the potential of multipurpose applications of moderate-temperature geothermal waters in the vicinity of the Baca Grande community development in the San Luis Valley, Colorado. The project resource assessment, based on a thorough review of existing data, indicates that a substantial resource likely exists in the Baca Grande region capable of supporting residential and light industrial activity. Engineering designs were developed for geothermal district heating systems for space heating and domestic hot water heating for residences, including a mobile home park, an existing motel, a greenhouse complex, and other small commercial uses such as aquaculture. In addition, a thorough institutional analysis of the study area was performed to highlight factors which might pose barriers to the ultimate commercial development of the resource. Finally, an environmental evaluation of the possible impacts of the proposed action was also performed. The feasibility evaluation indicates the economics of the residential areas are dependent on the continued rate of housing construction. If essentially complete development could occur over a 30-year period, the economics are favorable as compared to existing alternatives. For the commercial area, the economics are good as compared to existing conventional energy sources. This is especially true …
Date:
May 1, 1980
Creator:
Goering, S.W.; Garing, K.L.; Coury, G.E. & Fritzler, E.A.
Object Type:
Report
System:
The UNT Digital Library
Combustible radioactive waste treatment by incineration and chemical digestion
A review is given of present and planned combustible radioactive waste treatment systems in the US. Advantages and disadvantages of various systems are considered. Design waste streams are discussed in relation to waste composition, radioactive contaminants by amount and type, and special operating problems caused by the waste.
Date:
May 28, 1980
Creator:
Stretz, L. A.; Crippen, M. D. & Allen, C. R.
Object Type:
Article
System:
The UNT Digital Library
Modeling of Integrated Environmental Control Systems for Coal-Fired Power Plants Quarterly Report: Final Report
The Integrated Environmental Control Model (IECM) was designed to permit the systematic evaluation of environmental control options for pulverized coal-fired (PC) power plants. Of special interest was the ability to compare the performance and cost of advanced pollution control systems to conventional'' technologies for the control of particulate, SO{sub 2} and NO{sub x}. Of importance also was the ability to consider pre-combustion, combustion and post-combustion control methods employed alone or in combination to meet tough air pollution emission standards. Finally, the ability to conduct probabilistic analyses is a unique capability of the IECM. Key results are characterized as distribution functions rather than as single deterministic values. (VC)
Date:
May 1, 1991
Creator:
Rubin, E. S.; Salmento, J. S.; Frey, H. C.; Abu-Baker, A. & Berkenpas, M.
Object Type:
Report
System:
The UNT Digital Library
GCFR core thermal-hydralic design
The approach for developing the thermal-hydraulic core assembly designs for the gas-cooled fast reactor (GCFR) is reviewed, and key considerations for improving the core performance at all power and flow conditions are discussed. It is shown how the thermal-hydraulic core assembly designs evolve from evaluations of plant size, material limitations, safety criteria, and structural performance considerations.
Date:
May 1, 1980
Creator:
Schleuter, G.; Baxi, C.B. & Bennett, F.O.
Object Type:
Article
System:
The UNT Digital Library
Cs/sup +/ + Cs/sup +/ charge-transfer and ionization cross-section measurements by a plasma-target technique
A Q machine plasma target using cesium was constructed to serve as a target for a beam of Cs/sup +/ ions. The sum of charge transfer and ionization cross sections was determined by measuring the growth of the Cs/sup + +/ component of the beam as a function of the plasma radial line density. The measured cross section varies approximately linearly with energy between 50 and 110 keV. This loss cross section is 0.47 +- .11 x 10/sup -16/ cm/sup 2/ at 110 keV. These results have been compared to the cross section determined by a crossed-beam technique. The agreement between the results of the experiments is good at energies above 75 keV. A discrepancy between the results at lower energies indicated a systematic error in one of the techniques. Theoretical estimates of the cross section recently have begun to agree with the magnitude of the cross section but have not fully explained the energy dependence.
Date:
May 1, 1982
Creator:
Stalder, K.R.
Object Type:
Report
System:
The UNT Digital Library