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Attrition Resistant Fischer-Tropsch Catalysts Based on FCC Supports (open access)

Attrition Resistant Fischer-Tropsch Catalysts Based on FCC Supports

Commercial spent fluid catalytic cracking (FCC) catalysts provided by Engelhard and Albemarle were used as supports for Fe-based catalysts with the goal of improving the attrition resistance of typical F-T catalysts. Catalysts with the Ruhrchemie composition (100 Fe/5 Cu/4.2 K/25 spent FCC on mass basis) were prepared by wet impregnation. XRD and XANES analysis showed the presence of Fe{sub 2}O{sub 3} in calcined catalysts. FeC{sub x} and Fe{sub 3}O{sub 4} were present in the activated catalysts. The metal composition of the catalysts was analyzed by ICP-MS. F-T activity of the catalysts activated in situ in CO at the same conditions as used prior to the attrition tests was measured using a fixed bed reactor at T = 573 K, P = 1.38 MPa and H{sub 2}:CO ratio of 0.67. Cu and K promoted Fe supported over Engelhard provided spent FCC catalyst shows relatively good attrition resistance (8.2 wt% fines lost), high CO conversion (81%) and C{sub 5}+ hydrocarbons selectivity (18.3%).
Date: February 5, 2010
Creator: Adeyiga, Adeyinka
Object Type: Report
System: The UNT Digital Library
Paleoclimatic implications of glacial and postglacial refugia for Pinus pumila in western Beringia (open access)

Paleoclimatic implications of glacial and postglacial refugia for Pinus pumila in western Beringia

Palynological results from Julietta Lake currently provide the most direct evidence to support the existence of a glacial refugium for Pinus pumila in mountains of southwestern Beringia. Both percentages and accumulation rates indicate the evergreen shrub survived until at least {approx}19,000 14C yr B.P. in the Upper Kolyma region. Percentage data suggest numbers dwindled into the late glaciation, whereas pollen accumulation rates point towards a more rapid demise shortly after {approx}19,000 14C yr B.P. Pinus pumila did not re-establish in any great numbers until {approx}8100 14C yr B.P., despite the local presence {approx}9800 14C yr B.P. of Larix dahurica, which shares similar summer temperature requirements. The postglacial thermal maximum (in Beringia {approx}11,000-9000 14C yr B.P.) provided Pinus pumila shrubs with equally harsh albeit different conditions for survival than those present during the LGM. Regional records indicate that in this time of maximum warmth Pinus pumila likely sheltered in a second, lower-elevation refugium. Paleoclimatic models and modern ecology suggest that shifts in the nature of seasonal transitions and not only seasonal extremes have played important roles in the history of Pinus pumila over the last {approx}21,000 14C yr B.P.
Date: February 5, 2010
Creator: Anderson, P M; Lozhkin, A V; Solomatkina, T B & Brown, T A
Object Type: Article
System: The UNT Digital Library
South Texas Catholic (Corpus Christi, Tex.), Vol. 45, No. 3, Ed. 1 Friday, February 5, 2010 (open access)

South Texas Catholic (Corpus Christi, Tex.), Vol. 45, No. 3, Ed. 1 Friday, February 5, 2010

Semi-monthly newspaper from Corpus Christi, Texas published by the Diocese of Corpus Christi that includes news of interest to Diocese members along with advertising.
Date: February 5, 2010
Creator: Beaton, Paula J.
Object Type: Newspaper
System: The Portal to Texas History

Update on Digitization Projects at the University of North Texas (UNT)

This presentation gives an update on the Digital Library and The Portal to Texas History collections held by the University of North Texas (UNT) Libraries in 2010.
Date: February 5, 2010
Creator: Belden, Dreanna
Object Type: Presentation
System: The UNT Digital Library
Perry Daily Journal (Perry, Okla.), Vol. 118, No. 25, Ed. 1 Friday, February 5, 2010 (open access)

Perry Daily Journal (Perry, Okla.), Vol. 118, No. 25, Ed. 1 Friday, February 5, 2010

Daily newspaper from Perry, Oklahoma that includes local, state, and national news along with advertising.
Date: February 5, 2010
Creator: Brown, Gloria
Object Type: Newspaper
System: The Gateway to Oklahoma History
The GV Tribune (Grandview, Tex.), Vol. 115, No. 6, Ed. 1 Friday, February 5, 2010 (open access)

The GV Tribune (Grandview, Tex.), Vol. 115, No. 6, Ed. 1 Friday, February 5, 2010

Weekly newspaper from Grandview, Texas that includes local, state, and national news along with advertising.
Date: February 5, 2010
Creator: Buck, Erin
Object Type: Newspaper
System: The Portal to Texas History
The Altus Times (Altus, Okla.), Vol. 112, No. 44, Ed. 1 Friday, February 5, 2010 (open access)

The Altus Times (Altus, Okla.), Vol. 112, No. 44, Ed. 1 Friday, February 5, 2010

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: February 5, 2010
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Boerne Star (Boerne, Tex.), Vol. 104, No. 11, Ed. 1 Friday, February 5, 2010 (open access)

The Boerne Star (Boerne, Tex.), Vol. 104, No. 11, Ed. 1 Friday, February 5, 2010

Semiweekly newspaper from Boerne, Texas that includes local, state, and national news along with advertising.
Date: February 5, 2010
Creator: Cartwright, Brian & Velvin, Candace E.
Object Type: Newspaper
System: The Portal to Texas History
The Baytown Sun (Baytown, Tex.), Vol. 90, No. 26, Ed. 1 Friday, February 5, 2010 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 90, No. 26, Ed. 1 Friday, February 5, 2010

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: February 5, 2010
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
NEUTRON MULTIPLICITY AND ACTIVE WELL NEUTRON COINCIDENCE VERIFICATION MEASUREMENTS PERFORMED FOR MARCH 2009 SEMI-ANNUAL DOE INVENTORY (open access)

NEUTRON MULTIPLICITY AND ACTIVE WELL NEUTRON COINCIDENCE VERIFICATION MEASUREMENTS PERFORMED FOR MARCH 2009 SEMI-ANNUAL DOE INVENTORY

The Analytical Development (AD) Section field nuclear measurement group performed six 'best available technique' verification measurements to satisfy a DOE requirement instituted for the March 2009 semi-annual inventory. The requirement of (1) yielded the need for SRNL Research Operations Department Material Control & Accountability (MC&A) group to measure the Pu content of five items and the highly enrich uranium (HEU) content of two. No 14Q-qualified measurement equipment was available to satisfy the requirement. The AD field nuclear group has routinely performed the required Confirmatory Measurements for the semi-annual inventories for fifteen years using sodium iodide and high purity germanium (HpGe) {gamma}-ray pulse height analysis nondestructive assay (NDA) instruments. With appropriate {gamma}-ray acquisition modeling, the HpGe spectrometers can be used to perform verification-type quantitative assay for Pu-isotopics and HEU content. The AD nuclear NDA group is widely experienced with this type of measurement and reports content for these species in requested process control, MC&A booking, and holdup measurements assays Site-wide. However none of the AD HpGe {gamma}-ray spectrometers have been 14Q-qualified, and the requirement of reference 1 specifically excluded a {gamma}-ray PHA measurement from those it would accept for the required verification measurements. The requirement of reference 1 was a new …
Date: February 5, 2010
Creator: Dewberry, R.; Ayers, J.; Tietze, F. & Klapper, K.
Object Type: Article
System: The UNT Digital Library
Frequency stabilization via the mixed mode in three mode HeNe lasers (open access)

Frequency stabilization via the mixed mode in three mode HeNe lasers

This paper describes a three mode HeNe laser frequency stabilization technique using the mixed mode frequency to obtain a fractional frequency stability of 2 x 10{sup -11}. The mixed mode frequency occurs due to optical nonlinear interactions with the adjacent modes at each of the three modes. In precision displacement interferometry systems, the laser source frequency must be stabilized to provide an accurate conversion ratio between phase change and displacement. In systems, such as lithography applications, which require high speed, high accuracy and low data age uncertainty, it is also desirable to avoid periodic nonlinearities, which reduces computation time and errors. One method to reduce periodic nonlinearity is to spatially separate the measurement and reference beams to prevent optical mixing, which has been shown for several systems. Using spatially separated beams and the proper optical configuration, the interferometer can be fiber fed, which can increase the interferometer's stability by reducing the number of beam steering optical elements. Additionally, as the number of measurement axes increases, a higher optical power from the laser source is necessary.
Date: February 5, 2010
Creator: Ellis, J D; Joo, K; Buice, E S; Spronck, J W & Munnig Schmidt, R H
Object Type: Article
System: The UNT Digital Library
Vulnerable Youth: Employment and Job Training Programs (open access)

Vulnerable Youth: Employment and Job Training Programs

This report provides an overview of federal employment programs for vulnerable young people. It begins with a discussion of the current challenges in preparing all youth today for the workforce. The report hen provides a chronology of job training and employment programs for at-risk youth that began in the 1930s.
Date: February 5, 2010
Creator: Fernandes, Adrienne L.
Object Type: Report
System: The UNT Digital Library
Partial Defect Verification of the Pressurized Water Reactor Spent Fuel Assemblies (open access)

Partial Defect Verification of the Pressurized Water Reactor Spent Fuel Assemblies

The International Atomic Energy Agency (IAEA) has the responsibility to carry out independent inspections of all nuclear material and facilities subject to safeguards agreements in order to verify compliance with non-proliferation commitments. New technologies have been continuously explored by the IAEA and Member States to improve the verification measures to account for declared inventory of nuclear material and detect clandestine diversion and production of nuclear materials. Even with these efforts, a technical safeguards challenge has remained for decades for the case of developing a method in identifying possible diversion of nuclear fuel pins from the Light Water Reactor (LWR) spent fuel assemblies. We had embarked on this challenging task and successfully developed a novel methodology in detecting partial removal of fuel from pressurized water reactor spent fuel assemblies. The methodology uses multiple tiny neutron and gamma detectors in the form of a cluster and a high precision driving system to obtain underwater radiation measurements inside a Pressurized Water Reactor (PWR) spent fuel assembly without any movement of the fuel. The data obtained in such a manner can provide spatial distribution of neutron and gamma flux within a spent fuel assembly. The combined information of gamma and neutron signature is used …
Date: February 5, 2010
Creator: Ham, Young S. & Sitaraman, Shivakumar
Object Type: Article
System: The UNT Digital Library
The Oklahoma Daily (Norman, Okla.), Vol. 95, No. 92, Ed. 1 Friday, February 5, 2010 (open access)

The Oklahoma Daily (Norman, Okla.), Vol. 95, No. 92, Ed. 1 Friday, February 5, 2010

Student newspaper of the University of Oklahoma in Norman, Oklahoma that includes national, local, and campus news along with advertising.
Date: February 5, 2010
Creator: Hughes, Jamie
Object Type: Newspaper
System: The Gateway to Oklahoma History
Financing the U.S. Trade Deficit (open access)

Financing the U.S. Trade Deficit

This report provides an overview of the U.S. balance of payments, an explanation of the broader role of capital flows in the U.S. economy, an explanation of how the country finances its trade deficit or a trade surplus, and the implications for Congress and the country of the large inflows of capital from abroad.
Date: February 5, 2010
Creator: Jackson, James K.
Object Type: Report
System: The UNT Digital Library
A novel heterodyne displacement interferometer with no detectable periodic nonlinearity and optical resolution doubling (open access)

A novel heterodyne displacement interferometer with no detectable periodic nonlinearity and optical resolution doubling

This paper describes a novel heterodyne laser interferometer with no significant periodic nonlinearity for linear displacement measurements. Moreover, the optical configurations have the benefit of doubling the measurement resolution when compared to its respective traditional counterparts. Experimental results show no discernable periodic nonlinearity for a retro-reflector interferometer and plane mirror interferometer configurations with a noise level below 20 pm. The incoming laser beams of the interferometers are achieved by utilizing two single mode optical fibers. To determine the stability of the optical fiber couplers a fiber delivery prototype was also built and tested.
Date: February 5, 2010
Creator: Joo, K; Ellis, J D; Buice, E S; Spronck, J W & Munnig Schmidt, R H
Object Type: Article
System: The UNT Digital Library
Analytical Validation of Accelerator Mass Spectrometry for Pharmaceutical Development: the Measurement of Carbon-14 Isotope Ratio. (open access)

Analytical Validation of Accelerator Mass Spectrometry for Pharmaceutical Development: the Measurement of Carbon-14 Isotope Ratio.

Accelerator mass spectrometry (AMS) is an isotope based measurement technology that utilizes carbon-14 labeled compounds in the pharmaceutical development process to measure compounds at very low concentrations, empowers microdosing as an investigational tool, and extends the utility of {sup 14}C labeled compounds to dramatically lower levels. It is a form of isotope ratio mass spectrometry that can provide either measurements of total compound equivalents or, when coupled to separation technology such as chromatography, quantitation of specific compounds. The properties of AMS as a measurement technique are investigated here, and the parameters of method validation are shown. AMS, independent of any separation technique to which it may be coupled, is shown to be accurate, linear, precise, and robust. As the sensitivity and universality of AMS is constantly being explored and expanded, this work underpins many areas of pharmaceutical development including drug metabolism as well as absorption, distribution and excretion of pharmaceutical compounds as a fundamental step in drug development. The validation parameters for pharmaceutical analyses were examined for the accelerator mass spectrometry measurement of {sup 14}C/C ratio, independent of chemical separation procedures. The isotope ratio measurement was specific (owing to the {sup 14}C label), stable across samples storage conditions for at …
Date: February 5, 2010
Creator: Keck, B D; Ognibene, T & Vogel, J S
Object Type: Article
System: The UNT Digital Library
["Here Comes the Payne" tape 3 of 3] captions transcript

["Here Comes the Payne" tape 3 of 3]

Video recording from The Black Academy of Arts and Letters recorded during the dress performance theatre series of "Here Comes the Payne" starring Carl Payne on February 5th, 2010 at the Clarence Muse Café Theatre. The footage shows Payne playing different versions of himself from his life and childhood from a comedic perspective.
Date: February 5, 2010
Creator: King, Curtis & Payne, Carl
Object Type: Video
System: The UNT Digital Library
The Rice Thresher, Vol. 97, No. 18, Ed. 1 Friday, February 5, 2010 (open access)

The Rice Thresher, Vol. 97, No. 18, Ed. 1 Friday, February 5, 2010

A weekly student newspaper from the Rice University in Houston, Texas that includes campus news and commentaries along with advertising.
Date: February 5, 2010
Creator: Michel, Casey
Object Type: Newspaper
System: The Portal to Texas History
Dallas Voice (Dallas, Tex.), Vol. 26, No. 38, Ed. 1 Friday, February 5, 2010 (open access)

Dallas Voice (Dallas, Tex.), Vol. 26, No. 38, Ed. 1 Friday, February 5, 2010

Weekly newspaper from Dallas, Texas that includes local, state, and national news and advertising of interest to the Lesbian, Gay, Bisexual, and Transgender (LGBT) community.
Date: February 5, 2010
Creator: Nash, Tammye
Object Type: Newspaper
System: The UNT Digital Library
["Here Comes the Payne" tape 1 of 3] captions transcript

["Here Comes the Payne" tape 1 of 3]

Video recording from The Black Academy of Arts and Letters recorded during the dress performance theatre series of "Here Comes the Payne" starring Carl Payne on February 5th, 2010 at the Clarence Muse Café Theatre. The footage shows Payne playing different versions of himself from his life and childhood from a comedic perspective.
Date: February 5, 2010
Creator: Payne, Carl & King, Curtis
Object Type: Video
System: The UNT Digital Library
["Here Comes the Payne" tape 2 of 3] captions transcript

["Here Comes the Payne" tape 2 of 3]

Video recording from The Black Academy of Arts and Letters recorded during the dress performance theatre series of "Here Comes the Payne" starring Carl Payne on February 5th, 2010 at the Clarence Muse Café Theatre. The footage shows Payne playing different versions of himself from his life and childhood from a comedic perspective.
Date: February 5, 2010
Creator: Payne, Carl & King, Curtis
Object Type: Video
System: The UNT Digital Library

Storage 101: The Basics

This presentation discusses storage options for digital content, questions to ask when planning, and things to consider for storing and digitizing data.
Date: February 5, 2010
Creator: Phillips, Mark Edward
Object Type: Presentation
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Friday, February 5, 2010 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Friday, February 5, 2010

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: February 5, 2010
Creator: Pittman, Jerry & Wray, Kelly
Object Type: Newspaper
System: The Gateway to Oklahoma History