71 research outputs found
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Development of polymer concrete for dike insulation at LNG facilities: Phase 4, Low cost materials
Earlier GRI-sponsored work at Brookhaven National Laboratory has resulted in the development and utilization of insulating polymer concrete composites (IPC) as a means of reducing the evaporation rate of liquified natural gas in the event of a spill into a containment dike, thereby improving the safety at these sites. Although all of the required properties can be attained with the IPC, it was estimated that a low-cost replacement for the expensive organic binder would be necessary before use of the material would be cost-effective. In the current program, several latex modified cement formulations were evaluated and the most promising one identified. A mixture of two carboxylated styrene-butadiene latexes was selected for use in detailed laboratory property characterizations and a subsequent field evaluation. When compared to the properties of IPC, the latex-modified insulating materials display somewhat higher thermal conductivities, greater permeability to water, and reduced strength. However, these properties still meet most of the performance criteria, and the unit cost of the material is less than one-fifth that of IPC made with epoxy binders. When installed as a 0.75-in. thick overlay, material costs are estimated to be $1.00/ft{sup 2}
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Current Status of Geothermal Well Cement Development
The results of a study made in 1976 indicated that the cements used for well completion deteriorate in the geothermal environments and that the life expectancy of a well, and therefore the economics of geothermal processes, could be improved significantly if better materials were developed. On the basis of this assessment, Brookhaven National Laboratory (BNL) helped the Department of Energy, Division of Geothermal Energy to organize a program to develop materials that meet the estimated design criteria for geothermal well cements. The BNL work involves research on polymer cements and full management of an integrated program involving contract research and industrial participation. The program consists of the following phases: (1) problem definition, (2) cement research and development, (3) property verification, (4) downhole testing, and (5) cementing of demonstration wells
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Lost circulation control materials. Progress report
Work in FY 94 continued to investigate the use of calcium phosphate cements as lost circulation control materials for geothermal wells. The calcium phosphate cements were produced by reacting calcium aluminate cement with sodium phosphate compounds. Pumpable formulations with thickening times up to two hours at temperatures between 25 to 90{degrees}C were developed and characterized. The materials showed rapid set behaviour, early strength development, low permeability and acceptable durability in hydrothermal environments. Strengths up to 4 MPa were achieved four hours after mixing and water permeabilities were of the order of 10{sup -9} to 10{sup -7} cm/s at 24 hours. Partial replacement of calcium aluminate cement with ground granulated blast furnace slag was found to reduce the amount of borax retarder required to maintain pumpability at elevated temperatures and pressures
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Cementing of geothermal wells. Progress report No. 11, October-December 1978
In a one month shake-down test at East Mesa, 32 cement formulations were exposed to flowing brine at 150/sup 0/C and 95 psig. Based upon the results from this test, 15 formulations were selected for evaluation in a 2 year test. Experimental work indicates that none of the cements under consideration cause severe corrosion to steel casing. Compared with the possible corrosive attack on the steel casing by the geothermal environment, the corrosive effects of the cement are minimal. A promising cementing composition has been sent to the National Bureau of Standards for additional tests, and at least one more composition will be submitted. Pumpability tests performed on hydrothermal cements indicate several formulations that are pumpable for at least 2 hr at 316/sup 0/C. Polymer concrete samples containing 50 wt% styrene - 35 wt% acrylonitrile - 5 wt% acrylamide - 10 wt% divinyl benzene have not shown any reduction in strength after exposure to 25% brine at 240/sup 0/C for 8 months. This is the highest strength formulation to date and is the first formulation that has not exhibited any strength reduction after brine exposure. Strengths of 204 MPa and 162 MPa were measured at 20/sup 0/ and 150/sup 0/C, respectively, after 8 months in brine
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Remediation options for a chromium contaminated landfill using cementitious grouts
In-situ remediation of a chemical waste landfill with excessive chromium levels is being investigated as part of the Mixed Waste Landfill Integrated Demonstration. This paper is concerned with the design of advanced cementitious grouts for in-situ stabilization of chromium contaminated soil and in-situ installation of subsurface containment barriers. Grouts have been developed to improve the performance and cost effectiveness of remediation compared with conventional materials. In addition to restoration of chromium contaminated soils, the developed grouts have applications in other environmental operations where superior properties are required
CORROSION STUDIES FOR A FUSED SALT-LIQUID METAL EXTRACTION PROCESS FOR THE LIQUID METAL FUEL REACTOR
Corrosion screening tests were carried out on potential materials of construction for use in a fused salt-liquid metal extraction process plant. The corrodents of interest were NaCl--KCl-- MgCl/sub 2/ eutectic, LiCl--KCl eutectic, Bi-- U fuel, and BiCl/sub 3/, either separately or in various combinations. Screening tests to determine the resistance of a wide range of commercial alloys to the corrodents were performed in static and tilting-furnace capsules. Some ceramic materials were tested in static capsules. Largerscale tests of metallic materials were conducted in thermal convection loops and in a forced circulation loop. Some of the tests were conducted isothermally at 500 deg C, and others were performed under 40 to 50 deg C temperature differences at roughly the same teinperature level. On the basis of metallographic examination of exposed test tabs and chemical analyses of corrodents, it was found that the binary and ternary eutectics by themselves produced little attack on any of the materials tested. A wide variety of materials including 1020 mild steel, 2 1/4 Cr--1 Mo alloy steel, types 304 (ELC), 310, 316, 347, 430, and 446 stainless steel, 16-1 Croloy, Inconel, Hastelloy C, Inor-8, Mo, and Ta is, therefore, available for further study. Corrosion by the ternary salt-fuel system was characteristic of that produced by the fuel alone. Alloys such as 1020 mild steel, and 1 1/4 Cr--1/ 2 Mo, and 2 1/4 Cr--1 Mo alloy steel, which are resistant to fuel, would be likely choices at present for container materials. BiCl/sub 3/ produced extensive attack on ternary salt-fuel containers when the fuel contained insufficient concentrations of oxidizable solutes. Au and Al/sub 2/O/sub 3/ were the only materials not attacked by BiCl/sub 3/ in ternary salt alone. (auth
Quantitative cross-linking/mass spectrometry reveals subtle protein conformational changes:QCLMS reveals protein conformational changes
Realizing Stock Market Crashes: Stochastic Cusp Catastrophe Model of Returns under the Time-Varying Volatility
On the Reproducibility of Label-Free Quantitative Cross-Linking/Mass Spectrometry
Quantitative cross-linking/mass spectrometry (QCLMS) is an emerging approach to study conformational changes of proteins and multi-subunit complexes. Distinguishing protein conformations requires reproducibly identifying and quantifying cross-linked peptides. Here we analyzed the variation between multiple cross-linking reactions using bis[sulfosuccinimidyl] suberate (BS3)-cross-linked human serum albumin (HSA) and evaluated how reproducible cross-linked peptides can be identified and quantified by LC-MS analysis. To make QCLMS accessible to a broader research community, we developed a workflow that integrates the established software tools MaxQuant for spectra preprocessing, Xi for cross-linked peptide identification, and finally Skyline for quantification (MS1 filtering). Out of the 221 unique residue pairs identified in our sample, 124 were subsequently quantified across 10 analyses with coefficient of variation (CV) values of 14% (injection replica) and 32% (reaction replica). Thus our results demonstrate that the reproducibility of QCLMS is in line with the reproducibility of general quantitative proteomics and we establish a robust workflow for MS1-based quantitation of cross-linked peptides
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