Science.gov (United States)

... 5. The results of the bond strength measurements were compared to the surface cleanness of the aged EPDM as determined by the specified ...

British Library Electronic Table of Contents (United Kingdom)

Abstract Ethylene-propylene-diene rubber (EPDM)/samarium borate (SmBO3)/ethylene-vinyl acetate (EVA) copolymer and EPDM/antimony-doped tin oxide (ATO)/EVA composites are aged at 150C for different intervals. Surface modification is used to improve filler to matrix interphase. The main aim is to investigate the effect of filler type and vinyl acetate (VA) content in EVA on stability of EPDM composites. It is found that acidic ATO particles can lower pH level of EPDM composites and then promote the degradation of acetic acid during aging. Moreover, when VA content exceeds 14 wt %, the instable VA content causes more acetic acids escape during aging. With the increasing of aging time, EPDM/SmBO3 control and EPDM/SmBO3/EVA composites tend to become darker while EPDM/ATO and EPDM/ATO/EVA compos...

British Library Electronic Table of Contents (United Kingdom)

Nylon copolymer (PA6, 66) and ethylene propylene diene (EPDM) blends with and without compatibilizer were prepared by melt mixing using Brabender Plasticorder. The thermal stability of nylon copolymer (PA6, 66)/ethylene propylene diene rubber (EPDM) blends was studied using thermogravimetric analysis (TGA). The morphology of the blends was investigated using scanning electron microscopy (SEM). In this work, the effects of blend ratio and compatibilisation on thermal stability and crystallinity were investigated. The incorporation of EPDM rubber was found to improve the thermal stability of nylon copolymer. The kinetic parameters of the degradation process were also studied. A good correlation was observed between the thermal properties and phase morphology of the blends. By applying Coats ...

Science.gov (United States)

... MOLYBDENUM ALLOY GUN BARREL LINERS o0 in ... NEW POWDER TECHNOLOGIES FOR MOLYBDENUM ALLOY GUN BARREL LINERS ...

KoreaScience (Korea)

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International Nuclear Information System (INIS)

The primary function of the Waste Handling Shaft (WHS) at the Waste Isolation Pilot Plant (WIPP) is to permit the transfer of radioactive waste from the surface waste handling building to the underground storage area. It also serves as an intake shaft for small volumes of air during normal storage operations and as an emergency escape route. Part of the construction was the placement of a concrete liner and steel reinforced key in 1984. During a routine shaft inspection in May 1990, some degradation of the WHS concrete liner was observed between the depths of 800 and 900 feet below the ground surface. Detailed investigations of the liner had been carried out by Sandia National Laboratories and by Westinghouse Electric Corporation Waste Isolation Division (WID) through Lankard Materials Laboratory. Observations, reports, and data support the conclusion that the concrete degradation, resulting from attack by chemically ...

Science.gov (United States)

A common reinforced liner material is a cloth formed of PTFE fibers and fiber of ... and ablation protection provided. All of these methods of thermal ..... The influence of fiber content on the microstructures of the composites is ...

Energy Technology Data Exchange (ETDEWEB)

Previous laboratory tests of elastomer O-rings in coal liquefaction solvents conducted at L'Garde, Inc., indicated that certain ethylenepropylenediene monomer (EPDM) compounds provided the best performance when a backup ring was used to limit swelling. Before service testing in a pump at the Wilsonville, Alabama, Advanced Coal Liquefaction Research and Development Facility, tests of six selected elastomers in the appropriate Wilsonville-produced solvent were conducted at Oak Ridge National Laboratory (ORNL). The ORNL tests measured the elastomers' changes in cross section, weight, density, and relative flexibility. Although two perfluoroelastomers showed less degradation of most properties during these tests, it was decided to proceed with service testing of two EPDM elastomers because of their much lower cost. 5 refs., 14 figs., 7 tabs.

Energy Technology Data Exchange (ETDEWEB)

An alternative to synthetic materials for use in solar pond liners is to select clayey soils as hydraulic barriers. This option reduces the cost of construction and the risk of contamination of subsoil and groundwater by hot brines. This paper deals with the physical, chemical and hydraulic properties of different soils tested mainly as compacted clay liners. The underdeveloped nations have the option to use this type of liner, but before doing so several tests are recommended, including those for soil and water composition, permeability, plasticity and X-ray diffraction analysis. In this investigation the following samples are analyzed: native clayey soils with illite, montmorillonite and halloysite, treated and non-treated bentonites in powder and granulated form, a mixture of zeolite and sodium bentonite, and industrial minerals composed largely of halloysite, kaolinite and attapulgite selected clays. Neutral salt ...

CERN Document Server

We study the stellar and dust properties of a well-defined sample of local elliptical galaxies to investigate the relationship between host galaxy properties and nuclear activity. We select a complete sample of 45 ellipticals from the Palomar spectroscopic survey of nearby galaxies, which includes 20 low-luminosity active galactic nuclei classified as LINERs and 25 inactive galaxies. Using a stellar population synthesis method, we compare the derived stellar population properties of the LINER versus the inactive subsamples. We also study the dust and stellar surface brightness distributions of the central regions of these galaxies using high-resolution images obtained with the {\\it Hubble Space Telescope}. Relative to the inactive subsample, ellipticals hosting LINERs share similar total optical and near-infrared luminosity, central stellar velocity dispersions, and nuclear stellar populations as judged from their ...

Energy Technology Data Exchange (ETDEWEB)

A lightweight, low permeability liner for graphite epoxy composite compressed gas storage vessels. The liner is composed of polymers that may or may not be coated with a thin layer of a low permeability material, such as silver, gold, or aluminum, deposited on a thin polymeric layer or substrate which is formed into a closed bladder using torispherical or near torispherical end caps, with or without bosses therein, about which a high strength to weight material, such as graphite epoxy composite shell, is formed to withstand the storage pressure forces. The polymeric substrate may be laminated on one or both sides with additional layers of polymeric film. The liner may be formed to a desired configuration using a dissolvable mandrel or by inflation techniques and the edges of the film seamed by heat sealing. The liner may be utilized in most any type of gas storage system, and is particularly applicable ...

International Nuclear Information System (INIS)

The generation of fusion power from the Fast-Liner Reactor (FLR) concept envisages the implosion of a thin (3-mm) metallic cylinder (0.2-m radius by 0.2-m length) onto a preinjected plasma. This plasma would be heated to thermonuclear temperatures by adiabatic compression, pressure confinement would be provided by the liner inertia, and thermal insulation of the wall-confined plasma would be established by an embedded azimuthal magnetic field. A 2- to 3-mu s burn would follow the approx. 10"4 m/s radial implosion and would result in a thermonuclear yield equal to 10 to 15 times the energy initially invested into the liner kinetic energy. For implosions occurring once every 10 s a gross thermal power of 430 MWt would be generated. The results of a comprehensive systems study of both physics and technology (economics) optima are presented. Despite unresolved problems associated with both the physics and technology of the FLR, ...

British Library Electronic Table of Contents (United Kingdom)

Carbon black is widely used as an active filler in the rubber industry to improve the physical properties of rubber. The surface energy of carbon black is high compared to that of various elastomers like styrene?butadiene rubber (SBR), butadiene rubber (BR) and ethylene?propylene?diene rubber (EPDM). The work aims at reducing the surface energy of carbon black by modifying its surface for application especially in rubber blends. The present paper looks into the possibility of using plasma polymerisation of acetylene as a surface modification technique for carbon black in comparison with silica. Thermogravimetric analysis, wetting behaviour with various liquids of known surface tension and time of flight secondary ion mass spectrometry (ToF-SIMS) were used to characterise the carbon black b...

Energy Technology Data Exchange (ETDEWEB)

Laboratory tests have been done to assess the feasibility of using microwaves to manufacture refractory liner boards as used in the steel industry. Results show that microwaves cured and dried the product about ten times faster than the conventional gas-oven process. The quality of boards dried with microwaves appears to be as good or better than of those dried with gas. The potential for fast, energy-optimized drying in a small space has been demonstrated. Economically, the energy-cost of using microwaves is comparable to using gas when drying the last 30% moisture content, that is, for about the last 50% of the present gas-drying time. For higher moisture contents, such as encountered in the early stages of drying, the energy can be supplied at a lower cost by gas. 8 figs.

Energy Technology Data Exchange (ETDEWEB)

Contamination of the lube-oil with hard abrasive particles leads to a three-body abrasive wear mechanism that highly accelerates piston ring/cylinder liner wear in coal-fueled diesel engines. One approach to reducing that wear is to modify the size and orientation of surface asperities on the cylinder to enhance the formation of a hydrodynamic film, and to provide avenues of escape for particles that would otherwise be trapped in the wear zone. Another approach is to introduce additives into the contaminated lube-oil that further enhance hydrodynamic film formation, form chemical films on the wearing surfaces, or form films on the contaminant particles. This work focuses on defining the effects of cylinder liner surface finish, various configurations of slots in the cylinder liner surface, and various additives in the contaminated lube-oil on the wear process. Wear tests were initiated in a bench apparatus using coal-ash ...

Energy Technology Data Exchange (ETDEWEB)

The reconstruction of steel lining of the FFTF reactor building is described. The cold part of the lining has a simple structure and represents a steel sheet of 6.35 mm thickness welded to I-shaped imbedded in concrete, the hot part is meant for resisting the hot sodium contacting with it. The reconstruction has been reduced to the substitution of usual lining, the sheets of which are fixed in such a way that dangerous strains in metal arising at evaporation are excluded by the new structure admitting sheet deformation.

Energy Technology Data Exchange (ETDEWEB)

Studies were conducted to examine the pressure on fluid-filled cables of electric power transmission networks in the event of an oil leak. Transition splices between paper-insulated oil-impregnated cable systems (PILC) and solid dielectric cable is difficult to perform. A proper PILC is composed of a means to contain oil within the cable structure and to keep moisture out. A failure of the cable joint could occur if an oil leak dries out the paper. Since oil pressure in most PILC cables is high, strong mechanical means must be devised to contain the oil within the cable. Resin systems, heat shrink systems and wiped lead sleeves to reseal the PILC cable over the splice, are among the methods used to stop an oil leak. A system has been designed using an EPDM tube contained under mechanical pressure; it has proven to be effective over a wide range of pressure conditions. Test results utilizing this system were presented. 1 ref., 1 tab., 4 figs.

International Nuclear Information System (INIS)

The effects of various antioxidants and antioxidant concentrations on the radiation and thermal stability of EPDM and XLPE polymers used for insulation of electric cable in nuclear power plants were measured. The objective was to determine if particular antioxidants could be identified as being especially effective for stabilization against radiation aging and combined thermal and radiation aging. Elongation to rupture was used as the measure of stability. Materials were irradiated to doses up to 2 MGy (200 Mrad) at a dose rate of 200 to 300 Gy/h in the Cobalt-60 Gamma Irradiation Facility at the University of Virginia. All of the antioxidants tested, which were known to provide excellent thermal stability, also provided good stability for radiation aging and combined thermal/radiation aging, although small differences between antioxidants were noted. No antioxidant or antioxidant combination was identified as being especially outstanding. Stabilization against ...

International Nuclear Information System (INIS)

This study evaluates the degree to which surface impoundments at licensed facilities comply with significant changes in NRC requirements initiated by enactment of EPA's final environmental standards for uranium recovery facilities (40 CFR Part 192). Impoundment liner requirements, ground-water protection standards, ground-water monitoring and corrective action programs, and site closure standards are the most significant regulatory modifications. The compliance status of 30 conventional mills and 31 in-situ mines is determined from a review of Nuclear Regulatory Commission and agreement state docket files through November, 1983. Results of this review show that a majority of conventional uranium mill tailings management systems are deficient with respect to liner requirements for new impoundments or proposed expansions to existing impoundments, as well as with respect to some aspects of ground-water monitoring and compliance programs. ...

International Nuclear Information System (INIS)

Since the first round of conceptual fusion reactor designs in 1973 - 1974, there has been considerable progress in design improvement. Two recent tokamak designs of the Wisconsin and Culham groups, with increased plasma beta and wall loading (power density), lead to more compact reactors with easier maintenance. The Reference Theta-Pinch Reactor has undergone considerable upgrading in the design of the first wall insulator and blanket. In addition, a conceptual homopolar energy storage and transfer system has been designed. In the case of the mirror reactor, there are design changes toward improved modular construction and ease of handling, as well as improved direct converters. Conceptual designs of toroidal-multiple-mirror, liner-compression, and reverse-field pinch reactors are also discussed. A design is presented of a toroidal multiple-mirror reactor that combines the advantages of steady-state operation and high-aspect ratio. The ...

Science.gov (United States)

An exact solution method for the free vibration problem of thin circular cylindrical shells is presented. The differential equations of motion are solved directly with the use of simple Fourier series as the modal displacement functions. Stokes' transformation is exploited to obtain correct series expressions for the derivatives of the Fourier series. From this method an explicit expression of the exact frequency equation can be obtained for any kind of boundary conditions. The accuracy of the present method is checked against available data. The proposed method is then used to find the modal characteristics of the thermal liner of the Fast Test Reactor (FTR). The numerical results obtained are compared with finite element method solutions. (auth)

International Nuclear Information System (INIS)

The condition of spent nuclear fuel (SNF) in wet storage at ten Soviet-designed research reactors has been assessed in the light of international experience in order to identify any associated safety issues. These reactors use Al-clad UO2-Al or U-Al alloy dispersion fuels of ?20% enrichment that were fabricated in Russia; the reactors have been in operation since 1955-70. Although originally sent for reprocessing, much of the SNF generated over the last 25-30 years has been stored in fuel storage pools (FSPs) of variable water quality. The external condition of wet-stored SNF assemblies from the reactors surveyed varied from significant failure due to galvanic corrosion that was driven by poor water quality, through gradual pitting caused by slightly impure water, to a stable condition of no observable change in the oxidized Al alloy surface of the irradiated fuel. SNF stability in wet storage seems to depend on three factors: Al being the sole metal in the FSP (to avoid galvanic ...

Environmental Research Database

Objectives(1) Evaluate various insitu techniques for determination of the permeability of slurry walls and investigate the extent of material disturbance and fracturing during drilling and testing.~%~~%~(2) Perform laboratory tests of block samples obtained from the field testing site and compare the results with field measurements.~%~~%~(3) Investigate the mechanisms of drilling using a newly developed instrumented self-boring device and develop a theoretical framework for drilling mechanisms in soils.~% [continued...]DescriptionCement-bentonite and clay liner systems are used as components of containment systems by the environmental industry to control the migration of pollution. In the interest of public safety, following construction, there is a requirement to test these structures in orde to assess if they meet the design critetia. At present this is done only indirectly via laboratory testing on samples obtained from the ...

Energy Technology Data Exchange (ETDEWEB)

This article described a full-scale green renovation project undertaken by a construction management firm in Newton, Massachusetts. Chapman Construction and Design began renovating its own office building in late 2007 and completed it in September 2008. The firm set out to achieve LEED Platinum certification from the United States Green Building Council. The project involved energy saving modifications to its mechanical systems; replacing plumbing fixtures with high efficiency alternatives to reduce water consumption by at least 40 per cent; installing skylights and additional windows to allow more natural light into the interior space; salvaging doors, lighting, metal studs and masonry whenever possible; and using sustainable products such as recyclable carpets, tiles and low-VOC paint. The main feature of the renovation was a new 47 kW (DC) photovoltaic (PV) solar power array installed on the rooftop. The PV array includes 208 panels and a SunPower SPR-225 system that produces 55,000 ...

Energy Technology Data Exchange (ETDEWEB)

Cold Heavy Oil Production with Sand (CHOPS) is an enhanced oil recovery method that induces sand production to form a network of wormholes that increase the porosity and permeability of a formation. Under proper conditions, CHOPS can improve formation flow characteristics. Integrated well completion strategies that were used to increase oil production at Fula oil field on the south flank of Mughad Basin in Sudan were described. Limited sand influx provided a means for effective sand control while eliminating the need for conventional sand control processes. Cold heavy oil production with limited sand influx requires optimized completion methods to stimulate sand production, thereby reducing oil flow resistance and prolonging the sand removal operation cycle. Completion tests were performed in terms of different formation conditions including perforating completion; perforating and full sand control completion by screen liner; and perforating and limited sand ...

Energy Technology Data Exchange (ETDEWEB)

There are a number of characteristics exhibited by ceramic materials that may provide potential benefits for the reciprocating internal combustion engine. However, the brittle nature of these materials together with a variability in strength has created difficulties in applying ceramic materials to the engine environment. Although a wide range of physical properties is available from contemporary ceramic materials, a material offering consistently high strength has yet to be developed. For sliding-contact applications, desirable characteristics include good wear resistance, low friction, ability to join metals and good heat dissipation. Test results have shown that cam/follower components with cast iron cam sliding on a silicon nitride follower exhibit very low wear rates. The application of silicon carbide to face seals has also shown substantial reductions in both friction and wear when compared with conventional materials. The use of ceramic materials for in-cylinder components ...

Energy Technology Data Exchange (ETDEWEB)

Contents: expansion of pc mill application to plate mill and tandem cold mill; application of cluster type rolling mill (cr mill) for rolling of special steel (illustration); development of on-line roll grinding system with profile meter; development of new type jet pickling; new technology in continuous annealing furnace (illustration); anti-seismic testing system by 3-dimensional shaking table; development of mitsubishi hybrid desulfurization system; field performance of 500 mw advanced coal fired supercritical pressure operation boiler for unit no. 1 of tsuruga thermal power station, hokuriku electric power co., inc.; development of electronically controlled cylinder liner lubrication system for marine diesel engines; prediction technology on steady-state and transient performance of multi-air conditioners; a knowledge-based system approach to the autonomous piloting and navigation control of ships.

Energy Technology Data Exchange (ETDEWEB)

Engineering materials for use in low heat rejection engines are required to function under stringent tribological conditions. Severe wear damage and high friction between the components of the tribosystem limit the number of potential materials suitable for such application conditions. The superalloys X-750 and 188 are composed of alloying elements that not only promote a high mechanical and chemical stability but may also result in a reduced wear rate and friction coefficient at elevated temperatures. As a part of the DOE-ECUT Tribology program at Argonne, the present study was undertaken to evaluate the tribological characteristics of these alloys that will also be utilized as the substrates for ion beam deposited lubricous coatings. A wear test rig that crudely simulated the sliding conditions between a piston ring and a cylinder liner in an operating engine was utilized for friction and wear studies. The test results indicated that the wear and friction ...

Energy Technology Data Exchange (ETDEWEB)

Lining shafts and placing them in a given strata needs extensive computation. Therefore, it is natural that the use of electronic computing and of numerical methods in this mining area started early. For shafts being sunk in non-stable water-bearing strata the deformations and stresses of the freezing wall are analysed. The complex system of an outer lining in the shaft sinking stage is designed with regard to the elastic support of the strata. In cases of strata-embedded systems the tubbing liner can be shaped as the loads require. Here analysis of safety against buckling is very important. If a sliding shaft is built as a composite construction, there are advantages in determining the distribution of the material by numerical methods. The analysis of stability is possible only by numerical methods and could not be solved otherwise. The Finite Element Method proves itself as a very general tool to solve the problem of multi-axial states of stress in a foundation ...

Energy Technology Data Exchange (ETDEWEB)

Problems with the refractory liners of incinerator combustion chambers have accompanied incinerators from the very beginning. They increased during the past decade, owing to higher combustion temperatures required by law (17. BImSchV), the higher calorific values of the waste to be combusted, and the higher or changed pollutant concentrations in the waste materials. This caused the providers and the materials and the producers of incinerators to develop new refractory products and new design concepts, with a great variety of processes and cost levels. [German] Seit Beginn der Abfallverbrennung, insbesondere aber mit zunehmender Tendenz in den vergangenen 10 Jahren, wird ueber Probleme mit der Feuerfestauskleidung in den Brennkammern von Abfallverbrennungsanlagen geklagt. Als Gruende fuer die zunehmenden Korrosionsprobleme werden die hoeheren gesetzlich geforderten Verbrennungstemperaturen (17. BImSchV), die hoeheren Heizwerte der verbrannten Abfaelle und die ...

Science.gov (United States)

The long-term durability of bonds between adhesive resins and dentin is of significant importance for the longevity of bonded restorations. We carried out an in vivo one-year study to evaluate the durability of resin-dentin bonds in the oral cavity, as well as to test the hypothesis that the adhesive interface would show morphological changes in vivo over time. Very shallow saucer-shaped dentin cavities were prepared in 12 intact teeth of one Japanese monkey (Macaca fuscata) under general anesthesia. The cavities were restored with Clearfil Liner Bond II and Clearfil Photo Posterior resin composite. The teeth were extracted at three different times: immediately, and 180 and 360 days after placement of the restorations. One day after the monkey was killed, specimens of the three time periods were subjected to the micro-tensile bond test at a crosshead speed of 1 mm/min. The surfaces of the failed bonds were observed under a field emission scanning electron ...

Energy Technology Data Exchange (ETDEWEB)

Two mechanical design requirements are defined for the SSC Collider beam tube. First, the vacuum requirement (luminosity lifetime = 150 hrs). It requires the design of a pressure boundary within the cold mass vessel to provide a vacuum tunnel for the proton beam and to minimize the synchrotron radiation gas desorbtion with a suitable material. The Collider beam tube design is under an intensive activity to search for a material that will meet the luminosity requirement without a distributed pump or liner. Second is the tube wall`s resistivity requirement ({sigma}*t = 2E5 {Omega}{sup {minus}1}). For a 4.2 K beam tube the Cu thickness is 100 {mu}m (RRR=30,6.7 T, {sigma}=2E9{Omega}{sup {minus}1}m{sup {minus}1}). The copper yield strength is relatively low in comparison to steel and, therefore, the design of the steel layer is governed by the copper layer yield stress limit. A beam tube subjected to eddy current load in a quenching dipole requires an optimum diameter ...

Energy Technology Data Exchange (ETDEWEB)

Atterberg limits, free swell, and hydraulic conductivity tests were conducted to assess how wet-dry cycling affects the plasticity and swell of bentonite, and the hydraulic conductivity of geosynthetic clay liners (GCLs) hydrated with deionized (DI) water (pH 6.5), tap water (pH 6.8), and 0.0125-M CaCl{sub 2} solution (pH 6.2). The plasticity of bentonite hydrated with DI water increased during each wetting cycle, whereas the plasticity of bentonite hydrated with tap water and CaCl{sub 2} decreased during each wetting cycle. Wet-dry cycling in DI water and tap water had little effect on swelling of the bentonite, even after seven wet-dry cycles. However, swelling decreased dramatically after two wetting cycles with CaCl{sub 2} solution. Hydraulic conductivity of GCL specimens remained low during the first four wetting cycles ({approximately}1 x 10{sup {minus}9} cm/s). However, within five to eight cycles, the hydraulic conductivity of all specimens permeated with ...

Energy Technology Data Exchange (ETDEWEB)

Six safety initiatives have been identified for accelerating the resolution of waste tank safety issues and closure of unreviewed safety questions. Safety Initiative 5 is to reduce safety and environmental risk from tank leaks. Item d of Safety Initiative 5 is to complete corrosion studies of single-shell tanks to determine failure mechanisms and corrosion control options to minimize further degradation by June 1994. This report has been prepared to fulfill Safety Initiative 5, Item d. The corrosion mechanisms that apply to Hanford Site single-shell tanks are stress corrosion cracking, pitting/crevice corrosion, uniform corrosion, hydrogen embrittlement, and microbiologically influenced corrosion. The corrosion data relevant to the single-shell tanks dates back three decades, when results were obtained from in-situ corrosion coupons in a few single-shell tanks. Since that time there have been intertank transfers, evaporation, and chemical alterations of the waste. These activities have ...