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Executive Guide: Best Practices in Achieving Consistent, Accurate Physical Counts of Inventory and Related Property (open access)

Executive Guide: Best Practices in Achieving Consistent, Accurate Physical Counts of Inventory and Related Property

Guidance issued by the General Accounting Office with an abstract that begins "This draft Executive Guide describes fundamental practices and procedures used in the private sector to achieve consistent and accurate physical counts of inventory and related property. It summarizes the principles that have been successfully implemented by companies recognized for their outstanding record of inventory management. It also explains and describes leading practices from which the federal government may be able to draw lessons and ideas. This guide applies to most forms of federal inventory, but some of the discussed practices may not be applicable to various types of bulk, natural resource, and nonturning inventories, such as the Department of Energy's strategic petroleum reserve."
Date: July 1, 2001
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
International Journal of Government Auditing, July 2001, Vol. 28, No. 3 (open access)

International Journal of Government Auditing, July 2001, Vol. 28, No. 3

Other written product issued by the General Accounting Office with an abstract that begins "This journal of the International Organization of Supreme Audit Institutions (INTOSAI) includes articles regarding (1) the symposium of INTOSAI Development Initiative Training Specialists in Oslo, Norway from June 3-9, 2001; (2) the Arab Organization of Supreme Audit Institutions' (ARABOSAI) 8th Triennial General Assembly in Rabat, Morocco from April 24-27, 2001; (3) an audit profile of the Board of Audit and the Inspection of the Republic of Korea; and (4) activities within INTOSAI."
Date: July 1, 2001
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
International Journal of Government Auditing, July 2000, Vol. 27, No. 3 (Spanish Version) (open access)

International Journal of Government Auditing, July 2000, Vol. 27, No. 3 (Spanish Version)

Other written product issued by the General Accounting Office with an abstract that begins "This journal of the International Organization of Supreme Audit Institutions (INTOSAI) includes articles regarding: (1) the Food and Agriculture Organization's audit, management, and governance; (2) fighting corruption and fraud; (3) INTOSAI's conference on internal controls; (4) Romania's Court of Audit; (5) reports in print on auditing; and (6) activities inside INTOSAI."
Date: July 1, 2001
Creator: United States. General Accounting Office.
Object Type: Text
System: The UNT Digital Library
Final Report on LLNL Subcontract B503962 Atlas (open access)

Final Report on LLNL Subcontract B503962 Atlas

Determining and characterizing the effectiveness of run-time optimization techniques is particularly relevant to modern sparse linear algebra software libraries that tend to hide from the user the internal storage format. For instance, a certain storage structure may dictate a particular algorithmic approach. Once a general scheme of access has been found based on a storage structure, one promising idea involves analyzing the sparsity pattern of the matrix operand to find places where the efficient static optimization techniques may be re-used. There are numerous ways in which this can be done, and it is almost certain that there will be no provably best way. In this case, it will also be necessary to search the space of available options during run-time. We have experimented with a variety of techniques for optimizing sparse matrix vector multiplication to take instruction sets, functional units, and memory hierarchies into account on the Power 3 architecture. Sparse matrix-vector multiplication is of course the inner loop in any iterative solver, even multigrid, since it includes all the interpolation, restriction, and smoothing operations. The structural properties of the application leads to sparse matrices that feature a sufficiently regular pattern, so that the automatic optimization techniques already integrated in …
Date: July 1, 2001
Creator: Dongarra, J & Falgout, R
Object Type: Report
System: The UNT Digital Library
e+ e- collider in the VLHC tunnel. Proceedings, Workshop, Chicago, USA, March 9-11, 2001 (open access)

e+ e- collider in the VLHC tunnel. Proceedings, Workshop, Chicago, USA, March 9-11, 2001

This document is a collection of the contributions made to the March IIT workshop on an e{sup +}e{sup -} collider in the VLHC tunnel. This machine, which is based on a relatively conservative extrapolation of LEP technology, has a baseline luminosity of 10{sup 33}/cm{sup 2}/s at a CM energy of 370 GeV. The overall parameters and general description of such a machine is described in T. Sen and J. Norem, ''A Very Large Lepton Collider in the VLHC Tunnel'', to be published. A preprint of this paper is included as Appendix 2 of this report. The intention of the workshop was to define the parameters of such a collider and make them available to the community for use in further physics studies. It is clear that the machine cannot compete with a full scale linear collider. Its main interest would be if a VLHC were built and if a linear collider did not already exist. In this case, it could provide a limited and perhaps crucial view of low mass Higgs states. Although the study is incomplete, it does define rather well the parameters of the machine, as well as the challenges that the design faces. The study benefited greatly …
Date: July 1, 2001
Creator: Dugan, D., (ed.); /Cornell U., LEPP; Tollestrup, A., (ed.) & /Fermilab
Object Type: Article
System: The UNT Digital Library
Displacements and stress distribution in D0 Run IIb stave due to CTE mismatches (open access)

Displacements and stress distribution in D0 Run IIb stave due to CTE mismatches

A possible D0 Run IIb stave design currently under study is characterized by an outer carbon fiber stiffening shell with the silicon detectors mounted internally and a single central cooling line running between them; in this paper the stave will be analyzed for thermal compatibility since the different coefficient of thermal expansion in the materials may cause unpredictable stresses and strains in the structure. A simplified stave section has been modeled with finite elements for different materials configurations and the vertical and longitudinal displacements induced by the thermal gradient, together with the related stresses, have been computed. Finally, once selected the most suitable material combination, a more realistic model has been created in order to study the influence of the hybrid location along the ladders.
Date: July 1, 2001
Creator: Lanfranco, Giobatta & Fast, James
Object Type: Report
System: The UNT Digital Library
Lake Roosevelt Fisheries Evaluation Program : Meadow Creek vs. Lake Whatcom Stock Kokanee Salmon Investigations in Lake Roosevelt Annual Report 2000-2001. (open access)

Lake Roosevelt Fisheries Evaluation Program : Meadow Creek vs. Lake Whatcom Stock Kokanee Salmon Investigations in Lake Roosevelt Annual Report 2000-2001.

Lake Roosevelt has been stocked with Whatcom stock kokanee since 1989 to mitigate for anadromous salmon losses caused by the construction of Grand Coulee Dam. The primary objective of the hatchery plantings was to create a self-sustaining recreational fishery. Due to low return numbers, it was hypothesized a native stock of kokanee might perform better than the coastal Whatcom strain. Therefore, kokanee from Meadow Creek, a tributary of Kootenay Lake, British Columbia were selected as an alternative stock. Matched pair releases of Whatcom stock and Meadow Creek kokanee were made from Sherman Creek in late June 2000. Stock performance between Lake Whatcom and Meadow Creek kokanee was evaluated through three performance measures (1) returns to Sherman Creek, the primary egg collection facility, (2) returns to other tributaries, indicating availability for angler harvest, and (3) returns to the creel. A secondary objective was to evaluate the numbers collected at downstream fish passage facilities. Age 2 kokanee were collected during five passes through the reservoir, which included 89 tributaries between August 17th and November 7th, 2000. Sherman Creek was sampled once a week because it was the primary egg collection location. A total of 2,789 age 2 kokanee were collected, in which …
Date: July 1, 2001
Creator: McLellan, Holly J. & Scholz, Allan T.
Object Type: Report
System: The UNT Digital Library
Lake Roosevelt Fisheries Evaluation Program : Lake Whatcom Kokanee Salmon (Oncorhynchus nerka kennerlyi) : Investigations in Lake Roosevelt Annual Report 1999-2000. (open access)

Lake Roosevelt Fisheries Evaluation Program : Lake Whatcom Kokanee Salmon (Oncorhynchus nerka kennerlyi) : Investigations in Lake Roosevelt Annual Report 1999-2000.

Lake Whatcom stock kokanee have been planted in Lake Roosevelt since 1988 with the primary goal of establishing a self-sustaining fishery. Returns of hatchery kokanee to egg collection facilities and recruitment to the creel have been minimal. Therefore, four experiments were conducted to determine the most appropriate release strategy that would increase kokanee returns. The first experiment compared morpholine and non-morpholine imprinted kokanee return rates, the second experiment compared early and middle run Whatcom kokanee, the third experiment compared early and late release dates, and the fourth experiment compared three net pen release strategies: Sherman Creek hatchery vs. Sherman Creek net pens, Colville River net pens vs. Sherman Creek net pens, and upper vs. lower reservoir net pen releases. Each experiment was tested in three ways: (1) returns to Sherman Creek, (2) returns to other tributaries throughout the reservoir, and (3) returns to the creel. Chi-square analysis of hatchery and tributary returns indicated no significant difference between morpholine imprinted and non-imprinted fish, early run fish outperformed middle run fish, early release date outperformed late release fish, and the hatchery outperformed all net pen releases. Hatchery kokanee harvest was estimated at 3,323 fish, which was 33% of the total harvest. Return …
Date: July 1, 2001
Creator: McLellan, Holly J.; Scholz, Allan T.; McLellan, Jason G. & Tilson, Mary Beth
Object Type: Report
System: The UNT Digital Library
Models of Scherk-Schwarz Symmetry Breaking in 5D: Classification and Calculability (open access)

Models of Scherk-Schwarz Symmetry Breaking in 5D: Classification and Calculability

The form of the most general orbifold breaking of gauge, global and supersymmetries with a single extra dimension is given. In certain theories the Higgs boson mass is ultraviolet finite due to an unbroken local supersymmetry, which is explicitly exhibited. We construct: a 1 parameter SU(3) \times SU(2) \times U(1) theory with 1 bulk Higgs hypermultiplet, a 2 parameter SU(3) \times SU(2) \times U(1) theory with 2 bulk Higgs hypermultiplets, and a 2 parameter SU(5) \to SU(3) \times SU(2) \times U(1) theory with 2 bulk Higgs hypermultiplets, and demonstrate that these theories are unique. We compute the Higgs mass and compactification scale in the SU(3) \times SU(2) \times U(1) theory with 1 bulk Higgs hypermultiplet.
Date: July 1, 2001
Creator: Barbieri, Riccardo; Hall, Lawrence J. & Nomura, Yasunori
Object Type: Article
System: The UNT Digital Library
Fine particle exposure of prescribed fire workers in the Southeastern United States and a comparison of several particulate matter sampling methods. (open access)

Fine particle exposure of prescribed fire workers in the Southeastern United States and a comparison of several particulate matter sampling methods.

Personal exposure concentrations of particles with aerodynamic diameter <2.5 μm (PM2.5) of prescribed fire workers were measured at two locations in the southeastern United States. Non-impacted ambient concentrations were measured as an estimate of background concentrations during burn activities. Four sampling method comparison studies were designed and performed to compare the FRM with 1) other gravimetric PM2.5 sampling methods in ambient air, 2) optical PM2.5 sampling methods in indoor air, 3) an optical sampling method (Grimm) for particles with aerodynamic diameter <10 μm (PM10) in ambient air, and 4) a gravimetric PM2.5 sampling method downwind of prescribed fires. The gravimetric PM2.5 sampling methods agreed well in ambient air (R2>0.96 for all) except for the MiniVol, the optical PM2.5 sampling methods agree less well in indoor air,(R2>0.592), the Grimm optical PM10 method agrees well in ambient air(R2>0.944 for all), and the personal method agrees well (n=9, R2=0.994) downwind of prescribed fires.
Date: July 1, 2001
Creator: Yanosky, Jeffrey, David
Object Type: Text
System: The UNT Digital Library
Field Operations Program Neighborhood Electric Vehicles - Fleet Survey (open access)

Field Operations Program Neighborhood Electric Vehicles - Fleet Survey

This report summarizes a study of 15 automotive fleets that operate neighborhood electric vehicles(NEVs) in the United States. The information was obtained to help Field Operations Program personnel understand how NEVs are being used, how many miles they are being driven, and if they are being used to replace other types of fleet vehicles or as additions to fleets. (The Field Operations Program is a U.S. Department of Energy Program within the DOE Office of Energy Efficiency and Renewable Energy, Transportation Technologies). The NEVs contribution to petroleum avoidance and cleaner air can be estimated based on the miles driven and by assuming gasoline use and air emissions values for the vehicles being replaced. Gasoline and emissions data for a Honda Civic are used as the Civic has the best fuel use for a gasoline-powered vehicle and very clean emissions. Based on these conservation assumptions, the 348 NEVs are being driven a total of about 1.2 million miles per year. This equates to an average of 3,409 miles per NEV annually or 9 miles per day. It is estimated that 29,195 gallons of petroleum use is avoided annually by the 348 NEVs. This equates to 87 gallons of petroleum use avoided …
Date: July 1, 2001
Creator: Francfort, James Edward & Carroll, M.
Object Type: Report
System: The UNT Digital Library
Preliminary Drop Testing Results to Validate an Analysis Methodology for Accidental Drop Events of Containers for Radioactive Materials (open access)

Preliminary Drop Testing Results to Validate an Analysis Methodology for Accidental Drop Events of Containers for Radioactive Materials

The National Spent Nuclear Fuel Program, operating from the Idaho National Engineering and Environmental Laboratory (INEEL), developed the standardized Department of Energy (DOE) spent nuclear fuel (SNF) canister. During the development of this canister, more than twenty drop tests were completed, evaluating high strain behavior, puncture resistance, maintenance of containment, and other canister responses. Computer analyses of these drop-test specimens/canisters employed the ABAQUS/Explicit software. A pre-drop analysis was performed for each test specimen to predict the deformed shape and resulting material straining. Typically, a postdrop analysis was also performed to better match actual test specifics (actual impact angle, test specimen material properties, etc.). The purpose for this analysis effort was to determine the capability of current analysis techniques to accurately predict the deformed shape of a standardized DOE SNF canister subjected to a defined drop event, without actually having to perform a drop test for every drop event of interest. Those analytical efforts yielded very accurate predictions for nearly all of the drop tests. However, it was noted, during one small-scale test, that the calculated deformed shape of the test specimen depended on the modeled frictional behavior as it impacted the essentially unyielding flat surface. In order to calculate the …
Date: July 1, 2001
Creator: Snow, Spencer David; Morton, Dana Keith; Rahl, Tommy Ervin & Ware, Arthur Gates
Object Type: Article
System: The UNT Digital Library
Development of a dc Motor Model and an Actuator Efficiency Model (open access)

Development of a dc Motor Model and an Actuator Efficiency Model

For the past several years, researchers at the Idaho National Engineering and Environmental Laboratory, under the sponsorship of the U.S. Nuclear Regulatory Commission, have been investigating the ability of motor-operated valves (MOVs) used in Nuclear Power Plants to close or open when subjected to design basis flow and pressure loads. Part of this research addresses the response of a dcpowered motor-operated gate valve to assess whether it will achieve flow isolation and to evaluate whether it will slow down excessively under design-basis conditions and thus fail to achieve the required stroke time. As part of this research, we have developed a model of a dc motor operating under load and a model of actuator efficiency under load based on a first principle evaluation of the equipment. These models include the effect that reduced voltage at the Motor Control Center and elevated containment temperatures have on the performance of a dc powered MOV. The model also accounts for motor torque and speed changes that result from the heatup of the motor during the stroke. These models are part of the Motor- Operated Valve In Site Test Assessment (MISTA) software which is capable of independently evaluating the ability of dc-powered motoroperated gate …
Date: July 1, 2001
Creator: Watkins, John Clifford; Mc Kellar, Michael George & DeWall, Kevin George
Object Type: Article
System: The UNT Digital Library
RELAP5/MOD3.2 Assessment Using CHF Data from the KS-1 and V-200 Experiment Facilities (open access)

RELAP5/MOD3.2 Assessment Using CHF Data from the KS-1 and V-200 Experiment Facilities

The RELAP/MOD3.2 computer code has been assessed using rod bundle critical heat flux data from the KS-1 and V-200 facilities. This work was performed as part of the U.S. Department of Energy’s International Nuclear Safety Program, and is part of the effort addressing the capability of the RELAP5/MOD3.2 code to model transients in Soviet-designed reactors. Designated VVER Standard Problem 7, these tests addressed one of the important phenomena related to VVER behavior that the code needs to simulate well, core heat transfer. The code was judged to be in minimal agreement with the experiment data, consistently overpredicting the measured critical heat flux. It is recommended that a model development effort be undertaken to develop a critical heat flux model for RELAP5 that better represents the behavior in VVER rod bundles.
Date: July 1, 2001
Creator: Bayless, Paul David
Object Type: Report
System: The UNT Digital Library
Science and Technology Roadmapping to Support Project Planning (open access)

Science and Technology Roadmapping to Support Project Planning

Disciplined science and technology roadmapping provides a framework to coordinate research and development activities with project objectives. This case-history paper describes initial project technology needs identification, assessment and R&D ranking activities supporting characterization of 781 waste tanks requiring a &#39;hazardous waste determination&#39; or &#39;verification of empty&#39; decision to meet an Idaho state Voluntary Consent Order.
Date: July 1, 2001
Creator: Mc Carthy, Jeremiah Justin; Haley, Daniel Joseph & Dixon, Brent Wayne
Object Type: Article
System: The UNT Digital Library
Deactivation, Decontamination and Decommissioning Project Summaries (open access)

Deactivation, Decontamination and Decommissioning Project Summaries

This report is a compilation of summary descriptions of Deactivation, Decontamination and Decommissioning, and Surveillance and Maintenance projects planned for inactive facilities and sites at the INEEL from FY-2002 through FY-2010. Deactivations of contaminated facilities will produce safe and stable facilities requiring minimal surveillance and maintenance pending further decontamination and decommissioning. Decontamination and decommissioning actions remove contaminated facilities, thus eliminating long-term surveillance and maintenance. The projects are prioritized based on risk to DOE-ID, the public, and the environment, and the reduction of DOE-ID mortgage costs and liability at the INEEL.
Date: July 1, 2001
Creator: Peterson, David Shane & Webber, Frank Laverne
Object Type: Report
System: The UNT Digital Library
Ultrasonic Imaging of Subsurface Objects Using Photorefractive Dynamic Holography (open access)

Ultrasonic Imaging of Subsurface Objects Using Photorefractive Dynamic Holography

The INEEL has developed a photorefractive ultrasonic imaging technology that records both phase and amplitude of ultrasonic waves on the surface of solids. Phase locked dynamic holography provides full field images of these waves scattered from subsurface defects in solids, and these data are compared with theoretical predictions. Laser light reflected by a vibrating surface is imaged into a photorefractive material where it is mixed in a heterodyne technique with a reference wave. This demodulates the data and provides an image of the ultrasonic waves in either 2 wave or 4 wave mixing mode. These data images are recorded at video frame rates and show phase locked traveling or resonant acoustic waves. This technique can be used over a broad range of ultrasonic frequencies. Acoustic frequencies from 2 kHz to 10 MHz have been imaged, and a point measuring (non-imaging) version of the system has measured picometer amplitudes at 1 GHz.
Date: July 1, 2001
Creator: Deason, Vance Albert; Telschow, Kenneth Louis & Watson, Scott Marshall
Object Type: Article
System: The UNT Digital Library
Performance of MOV Stem Lubricants at Elevated Temperatures (open access)

Performance of MOV Stem Lubricants at Elevated Temperatures

This paper documents the results of recent tests sponsored by the U. S. Nuclear Regulatory Commission (NRC) and performed by the Idaho National Engineering and Environmental Laboratory (INEEL). These tests address the effectiveness of the lubricant used on the threaded portion of the valve stem, where the stem nut turns on the stem. Recent testing indicates that an elevated temperature environment can lead to significant increases in the friction coefficient at the stem/stem-nut interface. Most valve actuator qualification tests are performed at room temperature. Similarly, in-service tests are run at ambient plant temperatures, usually 70 to 100&#xb0;F. Since design conditions can lead to valve operating temperatures in the 200 to 300&#xb0;F range, it is important to know whether a temperature-induced increase in friction at the stem/stem-nut interface will prevent the required operation of critical valves. Lubricant aging is another phenomenon that might have deleterious effects on the thrust output of a valve actuator. Laboratory experience and field experience both indicate that after long periods in elevated temperature environments, the lubricants may lose their lubrication qualities. The scope of the current test program includes testing of five different lubricants on four different valve stems. Pending completion of the testing, results of …
Date: July 1, 2001
Creator: DeWall, Kevin George; Nitzel, Michael Everett & Watkins, John Clifford
Object Type: Article
System: The UNT Digital Library
From Prediction to Prescription: Intelligent Decision Support for Variable Rate Fertilization (open access)

From Prediction to Prescription: Intelligent Decision Support for Variable Rate Fertilization

We describe the use of machine learning methods in the analysis of spatial soil fertility, soil physical characteristics, and yield data, with a particular objective of determining local (field- to farm-scale) crop response patterns. For effective prescriptive use, the output of these tools is augmented with economic data and operational constraints, and recast as a rulebased decision support tool to maximize economic return in variable rate fertilization systems. We describe some of the practical issues addressed in development of one such system, including data preparation, adaptation of regression tree output for use in a rule-based expert system, and incorporation of real-world limits on system recommendations. Results from various field trials of this system are summarized.
Date: July 1, 2001
Creator: Fink, Raymond Keith; Hoskinson, Reed Louis & Hess, John Richard
Object Type: Article
System: The UNT Digital Library
Polk County Enterprise (Livingston, Tex.), Vol. 119, No. 51, Ed. 1 Sunday, July 1, 2001 (open access)

Polk County Enterprise (Livingston, Tex.), Vol. 119, No. 51, Ed. 1 Sunday, July 1, 2001

Semi-weekly newspaper from Livingston, Texas that includes local, state and national news along with advertising.
Date: July 1, 2001
Creator: White, Barbara
Object Type: Newspaper
System: The Portal to Texas History
Seminole Sentinel (Seminole, Tex.), Vol. 94, No. 74, Ed. 1 Sunday, July 1, 2001 (open access)

Seminole Sentinel (Seminole, Tex.), Vol. 94, No. 74, Ed. 1 Sunday, July 1, 2001

Semiweekly newspaper from Seminole, Texas that includes local, state, and national news along with extensive advertising.
Date: July 1, 2001
Creator: Dow, M. Gene & Fisher, David
Object Type: Newspaper
System: The Portal to Texas History
Losing weight to save lives: A review of the role of automobile weight and size in traffic fatalities (open access)

Losing weight to save lives: A review of the role of automobile weight and size in traffic fatalities

Critics of higher fuel economy standards for vehicles have long argued that improving vehicle fuel economy will require reducing vehicle weight, and that would result in an increase in the number of fatalities from vehicle crashes. Several researchers have estimated that an across-the-board reduction of vehicle weight would reduce passenger safety (Evans 1991; Kahane 1997; U.S. GAO 1994). However, little research has been done on the relationship of vehicle size and fatality rates, independent of weight (see, however, Joksch, Massie, and Pichler 1998). In this report we review previous analyses of the relationship of vehicle weight and safety. We do this to study the opportunities to improve fuel economy in a more sophisticated way than across-the-board mass reduction. The aim is to explore improvements in traffic safety by making selected vehicle groups lighter, and retaining or enlarging selected vehicle dimensions. Unfortunately, the effects of size and mass have not been accurately separated in the crash fatality data, so some of our claims are only supported by general arguments from physics. In a follow-up report we will attempt to analyze crash fatality data to determine crash worthiness if the weight of certain vehicle groups would be decreased while maintaining or increasing …
Date: July 1, 2001
Creator: Ross, Marc & Wenzel, Tom
Object Type: Report
System: The UNT Digital Library
Calcium Carbonate Production by Coccolithophorid Algae in Long Term, Carbon Dioxide Sequestration (open access)

Calcium Carbonate Production by Coccolithophorid Algae in Long Term, Carbon Dioxide Sequestration

Predictions of increasing levels of anthropogenic carbon dioxide (CO{sub 2}) and the specter of global warming have intensified research efforts to identify ways to sequester carbon. A number of novel avenues of research are being considered, including bioprocessing methods to promote and accelerate biosequestration of CO{sub 2} from the environment through the growth of organisms such as coccolithophorids, which are capable of sequestering CO{sub 2} relatively permanently. Calcium and magnesium carbonates are currently the only proven, long-term storage reservoirs for carbon. Whereas organic carbon is readily oxidized and releases CO{sub 2} through microbial decomposition on land and in the sea, carbonates can sequester carbon over geologic time scales. This proposal investigates the use of coccolithophorids single-celled, marine algae that are the major global producers of calcium carbonate to sequester CO{sub 2} emissions from power plants. Cultivation of coccolithophorids for calcium carbonate (CaCO{sub 3}) precipitation is environmentally benign and results in a stable product with potential commercial value. Because this method of carbon sequestration does not impact natural ecosystem dynamics, it avoids controversial issues of public acceptability and legality associated with other options such as direct injection of CO{sub 2} into the sea and ocean fertilization. Consequently, cultivation of coccolithophorids could …
Date: July 1, 2001
Creator: Fabry, V. J.
Object Type: Report
System: The UNT Digital Library
Mesoporous catalysts, supports and catalytic membranes based on MCM-41. Final report for the period January 15,2000 - January 14, 2001 (open access)

Mesoporous catalysts, supports and catalytic membranes based on MCM-41. Final report for the period January 15,2000 - January 14, 2001

The research had two objectives: to understand the effect of pore size on the chemistry and activity of active sites, and to investigate both the pore size and anchoring effect of Me-MCM-41 on Pt clusters (where Me is a metal incorporated in silica-based MCM-41). The focus is not on the effect of pore size on transport of reactants and products, but on how the local radius of curvature might affect the properties of a foreign ion embedded in a silicon wall that acts as a catalytic site or anchor for the catalytic site. The mesoporous molecular sieve, MCM-41, allows the variation of pore size with constant composition and pore geometry so these new materials allow this scientific question to be addressed for the first time. For the anchoring effect, concentration was on Sn-MCM-41 to prepare Pt/Sn-MCM-41 catalysts, by characterizing these and by testing them with probe reforming reactions (dehydrogenation, isomerization and aromatization). Although this is a final report on activity January 15, 2000 - January 14, 2001, this was a continuation of work initiated in the three-year grant period January 15, 1997 - January 14, 2000, so the summary of progress for these three years is appended for completeness.
Date: July 1, 2001
Creator: Haller, Gary L.
Object Type: Report
System: The UNT Digital Library