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Metagenomic analysis of phosphorus removing sludgecommunities

Description: Enhanced Biological Phosphorus Removal (EBPR) is not wellunderstood at the metabolic level despite being one of the best-studiedmicrobially-mediated industrial processes due to its ecological andeconomic relevance. Here we present a metagenomic analysis of twolab-scale EBPR sludges dominated by the uncultured bacterium, "CandidatusAccumulibacter phosphatis." This analysis resolves several controversiesin EBPR metabolic models and provides hypotheses explaining the dominanceof A. phosphatis in this habitat, its lifestyle outside EBPR and probablecultivation requirements. Comparison of the same species from differentEBPR sludges highlights recent evolutionary dynamics in the A. phosphatisgenome that could be linked to mechanisms for environmental adaptation.In spite of an apparent lack of phylogenetic overlap in the flankingcommunities of the two sludges studied, common functional themes werefound, at least one of them complementary to the inferred metabolism ofthe dominant organism. The present study provides a much-needed blueprintfor a systems-level understanding of EBPR and illustrates thatmetagenomics enables detailed, often novel, insights into evenwell-studied biological systems.
Date: February 1, 2006
Creator: Garcia Martin, Hector; Ivanova, Natalia; Kunin, Victor; Warnecke,Falk; Barry, Kerrie; McHardy, Alice C. et al.
Partner: UNT Libraries Government Documents Department
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Jupiter Oxygen Corporation/Albany Research Center Crada Progress Report, September

Description: The Albany Research Center (ARC) has developed a new Integrated Pollutant Removal (IPR) process for fossil-fueled boilers. Pursuant to a cooperative research and development agreement (CRADA) with Jupiter Oxygen Corporation, ARC currently is studying the IPR process as applied to the oxygen fuel technology developed by Jupiter. As discussed further below, these two new technologies are complementary. This interim report summarizes the study results to date and outlines the potential activities under the next phase of the CRADA with Jupiter.
Date: September 13, 2004
Creator: Turner, Paul C. & Schoenfield, Mark (Jupiter Oxygen Corp.)
Partner: UNT Libraries Government Documents Department
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Analysis of Breakthrough Profiles Based on Gamma Ray Emission Along Loaded Packed Bed Columns: Comparative Evaluation of Ionsiv IE-911 and Chabazite Zeolite for the Removal of Radiostrontium and Cesium from Groundwater

Description: A gamma counting system has been assembled that can profile the breakthrough fronts of gamma-emitting radioisotopes longitudinally and axially along a loaded column. This profiling technique has been particularly useful in columns studies such as those performed with IONSP IE-911, a crystalline silicotitanate (CST) manufactured by UOP, in which unusually long operating times are required to observe cesium breakthrough in column effluent. The length of the mass transfer zone and extent of column saturation can be detected early in a column study by viewing the relative emission of gamma emitters along I the length of the column. In this study, gamma scans were used to analyze loaded CST and zeolite columns used in the treatment of process wastewater simulant and actual groundwater. Results indicate good run-to-run reproductibility in acquiring the scans. The longitudinal gamma scans for both {sup 90}Sr and {sup 137}Cs conformed with breakthrough results reported on the basis of column effluent activity. Although not obvious from data obtained by monitoring effluent activity, the gamma scans indicated that both cesium and strontium in the saturated zone of the CST column are slowly displaced by the higher levels of groundwater cations and are then resorbed further down the column. This displacement phenomenon identified by gamma scans was verified using data from a zeolite column, in which both the gamma scan and column effluent data exhibited radionuclide displacement by groundwater cations. The gamma emission intensities from the CST column runs are used to quantitate and compare the distribution coefficient and loading capacity of {sup 137}Cs on CST versus zeolite.
Date: October 18, 1999
Creator: Bostick, D.T.; DePaoli, S.M. & Lucero, A.J.
Partner: UNT Libraries Government Documents Department
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Arsenic pilot plant operation and results - Socorro Springs, New Mexico - phase 1.

Description: Sandia National Laboratories (SNL) is conducting pilot scale evaluations of the performance and cost of innovative water treatment technologies aimed at meeting the recently revised arsenic maximum contaminant level (MCL) for drinking water. The standard of 10 {micro}g/L (10 ppb) is effective as of January 2006. The first pilot tests have been conducted in New Mexico where over 90 sites that exceed the new MCL have been identified by the New Mexico Environment Department. The pilot test described in this report was conducted in Socorro New Mexico between January 2005 and July 2005. The pilot demonstration is a project of the Arsenic Water Technology Partnership program, a partnership between the American Water Works Association Research Foundation (AwwaRF), SNL and WERC (A Consortium for Environmental Education and Technology Development). The Sandia National Laboratories pilot demonstration at the Socorro Springs site obtained arsenic removal performance data for five different adsorptive media under constant ambient flow conditions. Well water at Socorro Springs has approximately 42 ppb arsenic in the oxidized (arsenate-As(V)) redox state with moderate amounts of silica, low concentrations of iron and manganese and a slightly alkaline pH (8). The study provides estimates of the capacity (bed volumes until breakthrough at 10 ppb arsenic) of adsorptive media in the same chlorinated water. Near the end of the test the feedwater pH was lowered to assess the affect on bed capacity and as a prelude to a controlled pH study (Socorro Springs Phase 2).
Date: May 1, 2007
Creator: Aragon, Malynda Jo; Everett, Randy L.; Siegel, Malcolm Dean; Kottenstette, Richard Joseph; Holub, William E. Jr; Wright, Jeremy B. et al.
Partner: UNT Libraries Government Documents Department
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Analysis of Rod Removal Transient Experiments in VVER Reactors at Zero Power

Description: Within the context of the Fissile Materials Disposition Program of the U.S. Department of Energy we analyzed rod removal transient experiments performed at the Kurchatov Institute in a full-scale mockup of VVER reactors, The transients were started (via water inlet) in slightly (few cents) supercritical configurations with all the control rods withdrawn. After a few minutes, control rods banks or individual control rods were f and t inserted and later withdrawn (returning to the initial state). Available experimental data include the relative time profiles of nine incore and excore detectors. Because of the mild nature of the transients (very low power and no more than 2 $ reactivities) we decided to use a quasistatic approach. The time-dependent flux is factorized into two terms: a function of phase space, given by the solution of the static equation with parametric excitation; and a function of time, given by the solution of the point kinetic equations with time-dependent kinetics para meters. Due to the nature of the experiment, cold conditions, control rods withdrawn and critical state with water level, the power distributions, measured and calculated, are quite unusual, with the inner part of the core heavily shielded. Measured power levels at the center of the reactor are almost 20 times smaller than similar regions at the periphery. Transport and diffusion calculations of the power distributions are in reasonable agreement, so the division code BOLD-VENTURE was used to calculate the kinetics parameters and the relative changes of the detector field of view. The numerical integration of the time-dependent part of the solution was made with the LSODE package using ENDFIB-V and VI delayed neutron data. Very good results were obtained for the nine lime profiles.
Date: May 7, 2000
Creator: Difillippo, F.C.
Partner: UNT Libraries Government Documents Department
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Removal Action Plan for the Accelerated Retrieval Project for a Described Area within Pit 4

Description: This Removal Action Plan documents the plan for implementation of the Comprehensive Environmental Response, Compenstion, and Liability Act non-time-critical removal action to be performed by the Accelerated Retrieval Project. The focus of the action is the limited excavation and retrieval of selected waste streams from a designated portion of the Radioactive Waste Management Complex Subsurface Disposal Area that are contaminated with volatile organic compounds, isotopes of uranium, or transuranic radionuclides. The selected retrieval area is approximately 0.2 ha (1/2 acre) and is located in the eastern portion of Pit 4. The proposed project is referred to as the Accelerated Retrieval Project. This Removal Action Plan details the major work elements, operations approach, and schedule, and summarizes the environmental, safety and health, and waste management considerations associated with the project.
Date: August 1, 2006
Creator: Tyson, A. M.
Partner: UNT Libraries Government Documents Department
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Survey and Down-Selection of Acid Gas Removal Systems for the Thermochemical Conversion of Biomass to Ethanol with a Detailed Analysis of an MDEA System

Description: The first section (Task 1) of this report by Nexant includes a survey and screening of various acid gas removal processes in order to evaluate their capability to meet the specific design requirements for thermochemical ethanol synthesis in NREL's thermochemical ethanol design report (Phillips et al. 2007, NREL/TP-510-41168). MDEA and selexol were short-listed as the most promising acid-gas removal agents based on work described in Task 1. The second report section (Task 2) describes a detailed design of an MDEA (methyl diethanol amine) based acid gas removal system for removing CO2 and H2S from biomass-derived syngas. Only MDEA was chosen for detailed study because of the available resources.
Date: May 1, 2011
Creator: Nexant, Inc., San Francisco, California
Partner: UNT Libraries Government Documents Department
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Continual Non-Condensable Gas Removal Testing -- Performance and Lessons Learned

Description: The operating experience and plant benefit analysis of a membrane-based continuous non-condensable gas (NCG) removal system is discussed. Results from testing at the Mammoth Pacific (Ormat) geothermal plant provide the basis for the benefit analysis.
Date: September 1, 2005
Creator: Mohr, Charles & Mines, Greg
Partner: UNT Libraries Government Documents Department

Phosphorus Retention and Fractionation in Masonry Sand and Light Weight Expanded Shale Used as Substrate in a Subsurface Flow Wetland

Description: Constructed wetlands are considered an inefficient technology for long-term phosphorus (P) removal. The P retention effectiveness of subsurface wetlands can be improved by using appropriate substrates. The objectives of this study were to: (i) use sorption isotherms to estimate the P sorption capacity of the two materials, masonry sand and light weight expanded shale; (ii) describe dissolved P removal in small (2.7 m3) subsurface flow wetlands; (iii) quantify the forms of P retained by the substrates in the pilot cells; and (iv) use resulting data to assess the technical and economic feasibility of the most promising system to remove P. The P sorption capacity of masonry sand and expanded shale, as determined with Langmuir isotherms, was 60 mg/kg and 971 mg/kg respectively. In the pilot cells receiving secondarily treated wastewater, cells containing expanded shale retained a greater proportion of the incoming P (50.8 percent) than cells containing masonry sand (14.5 percent). After a year of operation, samples were analyzed for total P (TP) and total inorganic P (TIP). Subsamples were fractionated into labile-P, Fe+Al-bound P, humic-P, Ca+Mg-bound P, and residual-P. Means and standard deviations of TP retained by the expanded shale and masonry sand were 349 + 169 and 11.9 + 18.6 mg/kg respectively. The largest forms of P retained by the expanded shale pilot cells were Fe+Al- bound P (108 mg/kg), followed by labile-P (46.7 mg/kg) and humic-P (39.8). Increases in the P forms of masonry sand were greatest in labile-P (7.5 mg/kg). The cost of an expanded shale wetland is within the range of costs conventional technologies for P removal. Accurate cost comparisons are dependent upon expansion capacity of the system under consideration. Materials with a high P sorption capacity also have potential for enhancing P removal in other constructed wetland applications such as stormwater wetlands and wetlands …
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Date: August 2002
Creator: Forbes, Margaret G.
Partner: UNT Libraries
open access

The Removal Action Work Plan for CPP-603A Basin Facility

Description: This revised Removal Action Work Plan describes the actions to be taken under the non-time-critical removal action recommended in the Action Memorandum for the Non-Time Critical Removal Action at the CPP-603A Basins, Idaho Nuclear Technology and Engineering Center, as evaluated in the Engineering Evaluation/Cost Analysis for the CPP-603A Basin Non-Time Critical Removal Action, Idaho Nuclear Technology and Engineering Center. The regulatory framework outlined in this Removal Action Work Plan has been modified from the description provided in the Engineering Evaluation/Cost Analysis (DOE/NE-ID-11140, Rev. 1, August 2004). The modification affects regulation of sludge removal, treatment, and disposal, but the end state and technical approaches have not changed. Revision of this document had been delayed until the basin sludge was successfully managed. This revision (Rev. 1) has been prepared to provide information that was not previously identified in Rev. 0 to describe the removal, treatment, and disposal of the basin water at the Idaho National Laboratory (INL) CERCLA Disposal Facility evaporation ponds and fill the basins with grout/controlled low strength material (CLSM) was developed. The Engineering Evaluation/Cost Analysis for the CPP-603A Basin Non-Time Critical Removal Action, Idaho Nuclear Technology and Engineering Center - conducted pursuant to the Comprehensive Environmental Response, Compensation, and Liability Act - evaluated risks associated with deactivation of the basins and alternatives for addressing those risks. The decision to remove and dispose of the basin water debris not containing uranium grouted in place after the sludge has been removed and managed under the Hazardous Waste Management Act/Resource Conservation and Recovery Act has been documented in the Act Memorandum for the Non-Time Critical Removal Action at the CPP-603A Basins, Idaho Nuclear Technology and Engineering Center.
Date: June 5, 2006
Creator: Richards, B. T.
Partner: UNT Libraries Government Documents Department
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Enhanced Elemental Mercury Removal from Coal-fired Flue Gas by Sulfur-chlorine Compounds

Description: Oxidation of Hg0 with any oxidant or converting it to a particle-bound form can facilitate its removal. Two sulfur-chlorine compounds, sulfur dichloride (SCl2) and sulfur monochloride (S2Cl2), were investigated as oxidants for Hg0 by gas phase reaction and by surface-involved reactions in the presence of flyash or activated carbon. The gas phase reaction rate constants between Hg0 and the sulfur/chlorine compounds were determined, and the effects of temperature and the main components in flue gases were studied. The gas phase reaction between Hg0 and SCl2 is shown to be more rapid than the gas phase reaction with chlorine, and the second order rate constant was 9.1(+-0.5) x 10-18 mL-molecules-1cdots-1 at 373oK. Nitric oxide (NO) inhibited the gas phase reaction of Hg0 with sulfur-chlorine compounds. The presence of flyash or powdered activated carbon in flue gas can substantially accelerate the reaction. The predicted Hg0 removal is about 90percent with 5 ppm SCl2 or S2Cl2 and 40 g/m3 of flyash in flue gas. The combination of activated carbon and sulfur-chlorine compounds is an effective alternative. We estimate that co-injection of 3-5 ppm of SCl2 (or S2Cl2) with 2-3 Lb/MMacf of untreated Darco-KB is comparable in efficiency to the injection of 2-3 Lb/MMacf Darco-Hg-LH. Extrapolation of kinetic results also indicates that 90percent of Hg0 can be removed if 3 Lb/MMacf of Darco-KB pretreated with 3percent of SCl2 or S2Cl2 is used. Unlike gas phase reactions, NO exhibited little effect on Hg0 reactions with SCl2 or S2Cl2 on flyash or activated carbon. Mercuric sulfide was identified as one of the principal products of the Hg0/SCl2 or Hg0/S2Cl2 reactions. Additionally, about 8percent of SCl2 or S2Cl2 in aqueous solutions is converted to sulfide ions, which would precipitate mercuric ion from FGD solution.
Date: July 2, 2008
Creator: Chang, Shih-Ger; Yan, Nai-Qiang; Qu, Zan; Chi, Yao; Qiao, Shao-Hua; Dod, Ray et al.
Partner: UNT Libraries Government Documents Department
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Effectiveness of boundary-layer removal near throat of ramp-type side inlet at free-stream Mach number of 2.0

Description: Report presenting the effect of removal of the boundary layer inside the inlet on the performance of a twin-duct side-air-intake system in the 8- by 6-foot supersonic wind tunnel at a free-stream Mach number of 2.0. Results regarding the internal performance characteristics of inlets, supercritical mass-flow ratio, diffuser total-pressure recovery, and effect of bleeding the boundary layer are provided.
Date: November 17, 1954
Creator: Obery, Leonard J. & Cubbison, Robert W.
Partner: UNT Libraries Government Documents Department
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Experiments With a Wing From Which the Boundary Layer Is Removed by Pressure or Suction

Description: With an unsymmetrical wing and a rotating Magnus cylinder, the lift is produced by the superposition of parallel and circulatory flows. An explanation of the circulatory flow is furnished by the boundary-layer theory of Prandtl and the consequent vortex formation. According to this explanation, it must evidently be possible to increase the circulation either by increasing the size of the stronger (lower) vortex or by decreasing the size of the weaker (upper) vortex.
Date: July 1928
Creator: Wieland, K.
Partner: UNT Libraries Government Documents Department
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Impeachment and Removal

Description: This report discusses the impeachment process, which provides a mechanism for removal of the President, Vice President, and other "civil Officers of the United States" found to have engaged in "treason, bribery, or other high crimes and misdemeanors."
Date: October 29, 2015
Creator: Cole, Jared P. & Garvey, Todd
Partner: UNT Libraries Government Documents Department
open access

Impeachment: An Overview of Constitutional Provisions, Procedure, and Practice

Description: On June 19, 2009, the House voted to impeach U.S. District Judge Samuel B. Kent of the U.S. District Court for the Southern District of Texas. The impeachment process provides a mechanism for removal of the President, Vice President, and other federal civil officers found to have engaged in "treason, bribery, or other high crimes and misdemeanors." This report explains the impeachment process, including its history and the process itself.
Date: June 22, 2009
Creator: Bazan, Elizabeth B. & Henning, Anna C.
Partner: UNT Libraries Government Documents Department
open access

Hydraulic Performance and Gas Behavior of a Tall Crystalline Silicotitanate Ion-Exchange Column

Description: Crystalline silicotitanate (CST) sorbent is one of several technologies being evaluated by the Savannah River Site (SRS) for removing cesium from high-level tank-waste supernatant. As currently envisioned, three large 5-ft-diam, 20-ft-high ion-exchange columns will be operated in series at a superficial velocity of 4.1 cm/min. The CST will be subjected to a high radiation field from the sorbed cesium. The tests described in this work were conducted to evaluate column hydraulics, to identify changes in the CST particles during operation, to explore how radiolytic gases generated during operation behave, and to demonstrate sluicing of CST into and out of columns.
Date: February 1, 2000
Creator: Welch, T.D.; Anderson, K.K.; Bostick, D.A.; Dillow, T.A.; Getting, M.W.; Hunt, R.D. et al.
Partner: UNT Libraries Government Documents Department
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Pilot-Scale Testing of a Rotary Microfilter with Irradiated Filter Disks and Simulated SRS Waste

Description: The processing rate of the Actinide Removal Project (ARP) is limited by the flow rate of the solid-liquid separation process. If the Department of Energy, DOE, could identify and develop a solid- liquid separation technology with a higher filter flux, they could increase the throughput of the Actinide Removal Project and complete treating that fraction of the waste stream in a shorter time, with a significant reduction in life-cycle cost. Savannah River Technology Center personnel identified the rotary microfilter as a technology that could significantly increase filter flux, with improvements of as much as 10X over the 0.5 micron crossflow filter and 5X over the 0.1 micron crossflow filter. The Savannah River Technology Center received funding from the DOE-HQ, Office of Cleanup Technologies, to evaluate and develop the rotary microfilter for radioactive service at the Savannah River Site. The authors performed pilot-scale simulant filtration tests with irradiated filter disks. They employed three types of filter disks for the tests (0.5 m stainless steel, 0.1 m stainless steel, and 0.1 m ceramic/stainless steel). They analyzed the filter's structural material, Ryton(R) for hardness, and irradiated the entire disk with an estimated 2.5-5 year (83-165 MRad) radiation dose. They measured the hardness of the Ryton(R) after the irradiation of the disk. Following irradiation, they placed the filters in the pilot-scale rotary microfilter unit and tested them with feed slurries containing 0.29 and 4.5 wt per cent solids.
Date: January 20, 2004
Creator: POIRIER, MICHAELR.
Partner: UNT Libraries Government Documents Department
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Combined Active/Passive Decay Heat Removal Approach for the 24 Mwt Gas-Cooled Fast Reactor

Description: Decay heat removal at depressurized shutdown conditions has been regarded as one of the key areas where significant improvement in passive response was targeted for the GEN IV GFR over the GCFR designs of thirty years ago. It has been recognized that the poor heat transfer characteristics of gas coolant at lower pressures needed to be accommodated in the GEN IV design. The design envelope has therefore been extended to include a station blackout sequence simultaneous with a small break/leak. After an exploratory phase of scoping analysis in this project, together with CEA of France, it was decided that natural convection would be selected as the passive decay heat removal approach of preference. Furthermore, a double vessel/containment option, similar to the double vessel/guard vessel approach of the SFR, was selected as the means of design implementation to reduce the PRA risks of the depressurization accident. However additional calculations in conjunction with CEA showed that there was an economic penalty in terms of decay heat removal system heat exchanger size, elevation heights for thermal centers, and most of all in guard containment back pressure for complete reliance on natural convection only. The back pressure ranges complicated the design requirements for the guard containment. Recognizing that the definition of a loss-of-coolant-accident in the GFR is a misnomer, since gas coolant will always be present, and the availability of some driven blower would reduce fuel temperature transients significantly; it was decided instead to aim for a hybrid active/passive combination approach to the selected BDBA. Complete natural convection only would still be relied on for decay heat removal but only after the first twenty four hours after the initiation of the accident. During the first twenty four hour period an actively powered blower would be relied on to provide the emergency decay power removal. …
Date: June 1, 2007
Creator: Cheng, L. Y. & Ludewig, H.
Partner: UNT Libraries Government Documents Department
open access

A Comparison of Several Systems of Boundary-Layer Removal Ahead of a Typical Conical External-Compression Side Inlet at Mach Numbers of 1.88 and 2.93

Description: Report presenting an investigation at Mach numbers 1.88 and 2.93 to determine the performance characteristics of a conical external-compression side inlet model with a swept-leading-edge boundary-layer-removal scoop. Two other boundary-layer-removal systems were also investigated, which used a deflection wedge and cowl-lip scoops. Results regarding swept-scoop inlets, scoop performance, alternative boundary-layer-removal systems at Mach 1.88, and a comparison of the boundary layer removal systems are provided.
Date: September 4, 1953
Creator: Piercy, Thomas G. & Johnson, Harry W.
Partner: UNT Libraries Government Documents Department
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Executive Orders: Issuance and Revocation

Description: Executive orders and proclamations are used extensively by Presidents to achieve policy goals, set uniform standards for managing the Executive Branch, or outline a policy view intended to influence the behavior of private citizens. The Constitution does not define these presidential instruments, and does not explicitly vest the President with the authority to issue them. Nonetheless, such orders are accepted as an inherent aspect of presidential power, and, if based on appropriate authority, they have the force and effect of law. This report discusses the nature of executive orders and proclamations, with a focus on the scope of presidential authority to execute such instruments and judicial and congressional responses thereto.
Date: March 19, 2001
Creator: Halstead, T. J.
Partner: UNT Libraries Government Documents Department
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DUK - A Fast and Efficient Kmer Based Sequence Matching Tool

Description: A new tool, DUK, is developed to perform matching task. Matching is to find whether a query sequence partially or totally matches given reference sequences or not. Matching is similar to alignment. Indeed many traditional analysis tasks like contaminant removal use alignment tools. But for matching, there is no need to know which bases of a query sequence matches which position of a reference sequence, it only need know whether there exists a match or not. This subtle difference can make matching task much faster than alignment. DUK is accurate, versatile, fast, and has efficient memory usage. It uses Kmer hashing method to index reference sequences and Poisson model to calculate p-value. DUK is carefully implemented in C++ in object oriented design. The resulted classes can also be used to develop other tools quickly. DUK have been widely used in JGI for a wide range of applications such as contaminant removal, organelle genome separation, and assembly refinement. Many real applications and simulated dataset demonstrate its power.
Date: March 21, 2011
Creator: Li, Mingkun; Copeland, Alex & Han, James
Partner: UNT Libraries Government Documents Department
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Approaches to rid cathodic arc plasmas of macro- andnanoparticles: A review

Description: A major obstacle for the broad application of cathodic arc plasma deposition is the presence of micro- and nanoparticles in the plasma, also often referred to as 'macroparticles'. This paper reviews the formation of macroparticles at cathode spots, their interaction with the arc plasma and substrate, and macroparticle separation and removal from the plasma by various filtering methods. Nineteen variants of filters are discussed, including Aksenov's classic 90{sup o}-duct filter, filters of open architecture, and the concept of stroboscopic filtering.
Date: June 1, 1999
Creator: Anders, Andre
Partner: UNT Libraries Government Documents Department
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