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Safe Routes to School: Progress in Implementing the Program, but a Comprehensive Plan to Evaluate Program Outcomes Is Needed (open access)

Safe Routes to School: Progress in Implementing the Program, but a Comprehensive Plan to Evaluate Program Outcomes Is Needed

A letter report issued by the Government Accountability Office with an abstract that begins "In August 2005, Congress established the Safe Routes to School (SRTS) program primarily to encourage children to walk and bicycle to school. GAO was asked to determine (1) the steps the Federal Highway Administration (FHWA) and states have taken to implement the program, (2) the extent to which FHWA and states have evaluated the results of the program, and (3) how the program is related to other surface transportation programs and some considerations for future reauthorization. GAO reviewed statutes, regulations, and guidance; analyzed program obligation data and funds awarded by states; and interviewed officials with FHWA, state departments of transportation, and local grant recipients."
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Information Technology: Agencies Need to Establish Comprehensive Policies to Address Changes to Projects' Cost, Schedule, and Performance Goals (open access)

Information Technology: Agencies Need to Establish Comprehensive Policies to Address Changes to Projects' Cost, Schedule, and Performance Goals

A letter report issued by the Government Accountability Office with an abstract that begins "The federal government plans to spend about $70 billion on information technology (IT) projects during fiscal year 2008. Consequently, it is important that projects be managed effectively to ensure that public resources are wisely invested. At times, a project's cost, schedule, and performance goals--known as its baseline--are modified to reflect changed development circumstances. These changes--called a rebaselining--can be done for valid reasons, but can also be used to mask cost overruns and schedule delays. GAO was asked to (1) determine the extent of and the primary reasons for IT project rebaselining and (2) determine whether federal agencies have sound policies for rebaselining projects. To do this, GAO surveyed the managers of a random sample of 180 projects selected from the 778 major IT projects the 24 major agencies plan to invest in during fiscal year 2008. GAO also compared agencies' rebaselining policies to best practices."
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Military Personnel: Preliminary Observations on DOD's and the Coast Guard's Sexual Assault Prevention and Response Programs (open access)

Military Personnel: Preliminary Observations on DOD's and the Coast Guard's Sexual Assault Prevention and Response Programs

Testimony issued by the Government Accountability Office with an abstract that begins "In 2004, Congress directed the Department of Defense (DOD) to establish a comprehensive policy to prevent and respond to sexual assaults involving servicemembers. Though not required to do so, the Coast Guard has established a similar program. This statement addresses the extent to which DOD and the Coast Guard (1) have developed and implemented policies and programs to prevent, respond to, and resolve sexual assault incidents involving servicemembers; (2) have visibility over reports of sexual assault; and (3) exercise oversight over reports of sexual assault. This statement draws on GAO's preliminary observations from an ongoing engagement examining DOD's and the Coast Guard's programs to prevent and respond to sexual assault. In conducting its ongoing work GAO reviewed legislative requirements and DOD and Coast Guard guidance, analyzed sexual assault incident data, and obtained through surveys and interviews the perspective on sexual assault matters of more than 3,900 servicemembers stationed in the United States and overseas. The results of GAO's survey and interviews provide insight into the implementation of the programs but are nongeneralizable. GAO expects to issue its final report in August 2008 and to make a number of …
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Defense Acquisitions: Zumwalt-Class Destroyer Program Emblematic of Challenges Facing Navy Shipbuilding (open access)

Defense Acquisitions: Zumwalt-Class Destroyer Program Emblematic of Challenges Facing Navy Shipbuilding

Testimony issued by the Government Accountability Office with an abstract that begins "The U.S. Navy is about to begin construction of the first Zumwalt-class destroyer (DDG 1000) amid considerable uncertainties and a high likelihood of cost and schedule growth. Significant cost growth and schedule delays are persistent problems that continue to compromise the Navy's shipbuilding goals. This testimony focuses on (1) the challenges faced by the DDG 1000 program and (2) the strain such challenges portend for long term shipbuilding plans."
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Highlights of a Forum Convened by the Comptroller General of the United States: Enhancing U.S. Partnerships in Countering Transnational Terrorism (open access)

Highlights of a Forum Convened by the Comptroller General of the United States: Enhancing U.S. Partnerships in Countering Transnational Terrorism

Other written product issued by the Government Accountability Office with an abstract that begins "The United States and the international community have stressed that a coordinated response is required to address the global threat from transnational terrorism. Multilateral engagements provide opportunities to foster relationships with traditional and nontraditional partner countries. Partnerships also can raise common awareness of the threat and build the trust necessary to share information that could prevent and detect terrorist acts. GAO convened a forum on April 22, 2008, to advance the dialogue on how partnerships can mitigate the conditions that foster transnational terrorism and to identify potential strategies for overcoming challenges faced in engaging in such partnerships. Participants included representatives from U.S. government agencies, foreign embassies, nongovernmental and multilateral organizations, policy institutes, the private sector, and academia. The forum focused on (1) the partnership efforts and key practices of the U.S. government and its partners, (2) challenges to these efforts and practices, and (3) strategies to overcome the challenges. Comments expressed during the proceedings do not necessarily represent the views of all participants, the organizations they represent, or GAO. Participants reviewed a draft of this summary, and their comments were incorporated, as appropriate."
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Drug-Free Communities Support Program: Stronger Internal Controls and Other Actions Needed to Better Manage the Grant-Making Process (open access)

Drug-Free Communities Support Program: Stronger Internal Controls and Other Actions Needed to Better Manage the Grant-Making Process

A letter report issued by the Government Accountability Office with an abstract that begins "Twenty-five percent of American students ages 13-17 reported using illicit drugs in 2007. The Drug-Free Communities Support Program provides grants to community coalitions involved in reducing youth substance abuse. The Office of National Drug Control Policy (ONDCP) administers the program. ONDCP selected the Substance Abuse and Mental Health Services Administration (SAMHSA) to operate the grant program in fiscal year 2005. In 2005, ONDCP did not award grants to some coalitions who had previously received grant funds (renewal grantees). GAO was asked to assess (1) the extent to which ONDCP and SAMHSA administered grant-related activities for fiscal years 2005 and 2006 consistent with federal internal control standards, statutory requirements, and other guidance and (2) the steps ONDCP has taken since 2006 regarding its administration of grant-related activities. GAO analyzed and compared program documents and grant activities to established guidance, such as federal internal control standards and statutory requirements, and interviewed key program management officials."
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
2010 Census: Census Bureau's Decision to Continue with Handheld Computers for Address Canvassing Makes Planning and Testing Critical (open access)

2010 Census: Census Bureau's Decision to Continue with Handheld Computers for Address Canvassing Makes Planning and Testing Critical

A letter report issued by the Government Accountability Office with an abstract that begins "The U.S. Census Bureau (Bureau) had planned to rely heavily on automation in conducting the 2010 Census, including using handheld computers (HHC) to verify addresses. Citing concerns about escalating costs, in March 2008 the Secretary of Commerce announced a redesign of the key automation effort. GAO was asked to (1) analyze Bureau and contractor data showing how HHCs operated and their impact on operations, and (2) examine implications the redesign may have on plans for address canvassing in the 2010 Census. GAO reviewed Bureau and contractor data, evaluations, and other documents on HHC performance and staff productivity; interviewed Bureau and contractor officials; and visited the two dress rehearsal sites to observe and document the use of the HHCs in the field."
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Cyber Analysis and Warning: DHS Faces Challenges in Establishing a Comprehensive National Capability (open access)

Cyber Analysis and Warning: DHS Faces Challenges in Establishing a Comprehensive National Capability

A letter report issued by the Government Accountability Office with an abstract that begins "Cyber analysis and warning capabilities are critical to thwarting computer-based (cyber) threats and attacks. The Department of Homeland Security (DHS) established the United States Computer Emergency Readiness Team (US-CERT) to, among other things, coordinate the nation's efforts to prepare for, prevent, and respond to cyber threats to systems and communications networks. GAO's objectives were to (1) identify key attributes of cyber analysis and warning capabilities, (2) compare these attributes with US-CERT's current capabilities to identify whether there are gaps, and (3) identify US-CERT's challenges to developing and implementing key attributes and a successful national cyber analysis and warning capability. To address these objectives, GAO identified and analyzed related documents, observed operations at numerous entities, and interviewed responsible officials and experts."
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Combating Terrorism: Actions Needed to Enhance Implementation of Trans-Sahara Counterterrorism Partnership (open access)

Combating Terrorism: Actions Needed to Enhance Implementation of Trans-Sahara Counterterrorism Partnership

A letter report issued by the Government Accountability Office with an abstract that begins "In fiscal year 2005, the Trans-Sahara Counterterrorism Partnership (TSCTP) was established to eliminate terrorist safe havens in northwest Africa by strengthening countries' counterterrorism capabilities and inhibiting the spread of extremist ideology. Funds obligated for TSCTP in fiscal years 2005 through 2007 and committed for fiscal year 2008 by the Department of State (State), the U.S. Agency for International Development (USAID), and the Department of Defense (DOD) have amounted to about $353 million for activities in nine partner countries. In this report, GAO examines (1) the distribution of funds for TSCTP and the types of activities supported and (2) the program's implementation, including the extent to which it is guided by a comprehensive, integrated strategy. GAO has reported previously on the need for a strategy that includes priorities and milestones that can help agencies collaborate in combating terrorism. GAO analyzed TSCTP-related documents and conducted work in Mali, Morocco, and Mauritania."
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Airline Industry: Potential Mergers and Acquisitions Driven by Financial and Competitive Pressures (open access)

Airline Industry: Potential Mergers and Acquisitions Driven by Financial and Competitive Pressures

A letter report issued by the Government Accountability Office with an abstract that begins "The airline industry is vital to the U.S. economy, generating operating revenues of nearly $172 billion in 2007, amounting to over 1 percent of the U.S. gross domestic product. It serves as an important engine for economic growth and a critical link in the nation's transportation infrastructure, carrying more than 700 million passengers in 2007. Airline deregulation in 1978, led, at least in part, to increasingly volatile airline profitability, resulting in periods of significant losses and bankruptcies. In response, some airlines have proposed or are considering merging with or acquiring another airline. GAO was asked to help prepare Congress for possible airline mergers or acquisitions. This report describes (1) the financial condition of the U.S. passenger airline industry, (2) whether the industry is becoming more or less competitive, (3) why airlines seek to merge with or acquire other airlines, and (4) the role of federal authorities in reviewing proposed airline mergers and acquisitions. To answer these objectives, we analyzed Department of Transportation (DOT) financial and operating data; interviewed agency officials, airline managers, and industry experts; and reviewed Horizontal Merger Guidelines and spoke with antitrust experts. DOT …
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Veterans Affairs: Continued Action Needed to Reduce IT Equipment Losses and Correct Control Weaknesses (open access)

Veterans Affairs: Continued Action Needed to Reduce IT Equipment Losses and Correct Control Weaknesses

A letter report issued by the Government Accountability Office with an abstract that begins "In July 2004, GAO reported that the six Department of Veterans Affairs (VA) medical centers it audited lacked a reliable property control database and effective inventory policies and procedures. In July 2007, GAO reported that continuing internal control weaknesses over IT equipment at four case study locations at VA resulted in an increased risk of theft, loss, and misappropriation of IT equipment assets. GAO's two reports included 18 recommendations to improve internal control over IT equipment. GAO was asked to perform a follow-up audit to determine (1) whether VA has made progress in implementing GAO's prior recommendations for improving internal control over IT equipment and (2) the effectiveness of VA's current internal controls to prevent theft, loss, or misappropriation of IT equipment. GAO reviewed policies and other pertinent documentation, statistically tested IT equipment inventory controls at four geographically disparate locations, and interviewed VA officials."
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Ballistic Missile Defense: Actions Needed to Improve Process for Identifying and Addressing Combatant Command Priorities (open access)

Ballistic Missile Defense: Actions Needed to Improve Process for Identifying and Addressing Combatant Command Priorities

A letter report issued by the Government Accountability Office with an abstract that begins "In 2002, the Department of Defense (DOD) established the Missile Defense Agency to develop and deploy globally integrated ballistic missile defenses to protect the U.S. homeland, deployed forces, friends, and allies. To deliver an operational capability as quickly as possible, the agency was not subject to traditional DOD requirements and oversight processes. While directed to work closely with the combatant commands, the agency was not required to build missile defenses to meet specific operational requirements. GAO was asked to assess the extent to which DOD has developed a process that identifies, prioritizes, and addresses overall combatant command priorities as the Missile Defense Agency develops ballistic missile defense capabilities. To conduct its work, GAO reviewed relevant documents and visited several combatant commands, the Missile Defense Agency, Joint Staff, and other DOD organizations."
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Border Security: State Department Is Taking Steps to Meet Projected Surge in Demand for Visas and Passports in Mexico (open access)

Border Security: State Department Is Taking Steps to Meet Projected Surge in Demand for Visas and Passports in Mexico

A letter report issued by the Government Accountability Office with an abstract that begins "In fiscal year 2007, the U.S. Mission in Mexico (Mission Mexico) processed 1.5 million of the 8 million nonimmigrant visas (NIV) that the Department of State (State) handled worldwide. This workload is expected to increase dramatically in the coming years as millions of NIV Border Crossing Cards issued in Mexico during fiscal years 1998 to 2002 expire and need to be renewed. Consulates will also face increased workloads due to implementation of the Western Hemisphere Travel Initiative (WHTI), which will require U.S. citizens to carry passports, or other approved documentation, when traveling between the United States and Mexico, including by land. GAO was asked to review State's (1) estimates of the workload for consulates in Mexico through 2012 and (2) efforts to help ensure consulates keep pace with expected workload increases. GAO analyzed State's workload forecasts and forecast methodology, interviewed State officials, and visited five posts in Mexico."
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Defense Acquisitions: Cost to Deliver Zumwalt-Class Destroyers Likely to Exceed Budget (open access)

Defense Acquisitions: Cost to Deliver Zumwalt-Class Destroyers Likely to Exceed Budget

A letter report issued by the Government Accountability Office with an abstract that begins "In October 2008, the U.S. Navy will begin construction of the first of two lead DDG 1000 Zumwalt-class destroyers--at an expected cost of $6.3 billion. Given the history of cost growth on shipbuilding programs, as well as the Navy's request for approval of a third ship, GAO was asked to assess the progress of the program. GAO examined (1) whether key systems can be delivered on time and work as intended (2) design maturity (3) shipyard readiness and (4) whether lead and follow-on DDG 1000 ships can be built within budget. To accomplish this, our work included analysis of schedules, ship progress reviews and cost estimates; interviews with Navy and other officials; and our own past work."
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Rebuilding Iraq: DOD and State Department Have Improved Oversight and Coordination of Private Security Contractors in Iraq, but Further Actions Are Needed to Sustain Improvements (open access)

Rebuilding Iraq: DOD and State Department Have Improved Oversight and Coordination of Private Security Contractors in Iraq, but Further Actions Are Needed to Sustain Improvements

A letter report issued by the Government Accountability Office with an abstract that begins "The U.S. government relies extensively on private security contractors (PSC) for a variety of security services. However, incidents involving PSCs have raised concerns about oversight and legal accountability. Under the authority of the Comptroller General and in response to continuing congressional interest, GAO performed this review to examine the extent to which the Department of Defense (DOD) and Department of State have strengthened (1) oversight and (2) coordination of private security contractors in Iraq. GAO is also providing information on the legal framework used to hold private security contractor employees legally accountable for their actions in Iraq. GAO reviewed DOD and State Department policies and guidance, and their memorandum of agreement on PSCs; observed operations in Iraq and met with DOD officials there and in the U.S.; and met with officials from the Departments of Justice and State, and private security contractors."
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
TSA's Explosives Detection Canine Program: Status of Increasing Number of Explosives Detection Canine Teams (open access)

TSA's Explosives Detection Canine Program: Status of Increasing Number of Explosives Detection Canine Teams

Correspondence issued by the Government Accountability Office with an abstract that begins "This report formally transmits the attached briefing in response to section 1307 of the Implementing Recommendations of the 9/11 Commission Act of 2007. The act requires the Comptroller General to report on the utilization of explosives detection canine teams to strengthen security and the capacity of the national explosives detection canine team program, which is administered by the Transportation Security Administration."
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
United States Postal Service: Information on the Irradiation of Federal Mail in the Washington, D.C., Area (open access)

United States Postal Service: Information on the Irradiation of Federal Mail in the Washington, D.C., Area

Correspondence issued by the Government Accountability Office with an abstract that begins "In October 2001, spores of the deadly bacterium anthrax were found in mail sent to members of the news media and congressional leaders. In all, 22 people were infected with anthrax and 5 people died, including 2 postal workers. The United States Postal Service (Service) took a variety of steps to protect people from biohazards in the mail. For example, the Service began contracting for the irradiation of mail to recipients at the Congress, the White House, and federal agencies with specific ZIP Codes (20201 through 20597) in the Washington, D.C., area (D.C. federal mail). The irradiation process uses either a high-energy electron beam or X-rays to penetrate pieces of mail (mailpieces) and kill harmful organisms, such as anthrax. The Service initially hired two contractors to irradiate the mail, one of which operated between November 2001 and April 2002. The other contractor has been irradiating mail since November 2001. In addition, the Service hired contractors to transport the mail for irradiation and to oversee the current irradiation contractor. Senate Report 110-129, dated July 13, 2007, directed GAO to report on the status of the Service's program for irradiating …
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Information Technology: OMB and Agencies Need to Improve Planning, Management, and Oversight of Projects Totaling Billions of Dollars (open access)

Information Technology: OMB and Agencies Need to Improve Planning, Management, and Oversight of Projects Totaling Billions of Dollars

Testimony issued by the Government Accountability Office with an abstract that begins "The federal government spends billons of dollars on information technology (IT) projects each year. Consequently, it is important that projects be managed effectively to ensure that public resources are wisely invested. To this end, the Office of Management and Budget (OMB), which plays a key role in overseeing the federal government's IT investments, identifies major projects that are poorly planned by placing them on a Management Watch List and requires agencies to identify high-risk projects that are performing poorly (i.e., have performance shortfalls). Having accurate and transparent project cost and schedule information is also essential to effective oversight. At times, changes to this information--called a rebaselining-- are made to reflect changed development circumstances. These changes can be done for valid reasons, but can also be used to mask cost overruns and schedule delays. GAO has previously testified on the Management Watch List and high risk projects. GAO was asked to (1) provide an update on these projects, (2) identify OMB's efforts to improve the identification and oversight of these projects, and (3) summarize the results of GAO's IT project rebaselining report being released today. In preparing this testimony, …
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Veterans Health Administration: Improvements Needed in Design of Controls over Miscellaneous Obligations (open access)

Veterans Health Administration: Improvements Needed in Design of Controls over Miscellaneous Obligations

Testimony issued by the Government Accountability Office with an abstract that begins "The Veterans Health Administration (VHA) has been using miscellaneous obligations for over 60 years to record estimates of obligations to be incurred at a later time. The large percentage of procurements recorded as miscellaneous obligations in fiscal year 2007 raised questions about whether proper controls were in place over the authorization and use of billions of dollars. GAO's testimony provides preliminary findings related to (1) how VHA used miscellaneous obligations during fiscal year 2007, and (2) whether the Department of Veterans' Affairs (VA) policies and procedures were designed to provide adequate controls over their authorization and use. GAO recently provided its related draft report to the Secretary of Veterans Affairs for review and comment and plans to issue its final report as a follow-up to this testimony. GAO obtained and analyzed available VHA data on miscellaneous obligations, reviewed VA policies and procedures, and reviewed a nongeneralizable sample of 42 miscellaneous obligations at three case study locations. GAO's related draft report includes four recommendations to strengthen internal controls governing the authorization and use of miscellaneous obligations, in compliance with applicable federal appropriations law and internal control standards."
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Federal Information System Controls Audit Manual (FISCAM): Exposure Draft [Superseded by GAO-09-232G] (open access)

Federal Information System Controls Audit Manual (FISCAM): Exposure Draft [Superseded by GAO-09-232G]

Guidance issued by the Government Accountability Office with an abstract that begins "This document has been superseded by GAO-09-232G. This letter transmits the exposure draft of the Government Accountability Office (GAO) Federal Information System Controls Audit Manual (FISCAM) for review and comment. The FISCAM presents a methodology for performing information system (IS) control audits of federal and other governmental entities in accordance with professional standards, and was originally issued in January 1999. We have updated the FISCAM for significant changes affecting IS audits."
Date: July 31, 2008
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Panama: Political and Economic Conditions and U.S. Relations (open access)

Panama: Political and Economic Conditions and U.S. Relations

This report discusses the current political and economic conditions in the country of Panama, which has made notable political and economic progress since the 1989 U.S. military intervention that ousted the regime of General Manuel Noriega from power. The United States has close relations with Panama, stemming in large part from the extensive linkages developed when the canal was under U.S. control. This report describes the U.S.-Panama relationship at length, including trade relations.
Date: July 31, 2008
Creator: Sullivan, Mark P. & Rivas, Justin
Object Type: Report
System: The UNT Digital Library
ISOPAR L RELEASE RATES FROM SALTSTONE USING SIMULATED SALT SOLUTIONS (open access)

ISOPAR L RELEASE RATES FROM SALTSTONE USING SIMULATED SALT SOLUTIONS

The Modular Caustic-Side Solvent Extraction (CSSX) Unit (MCU) and the Salt Waste Processing Facility (SWPF) will produce a Decontaminated Salt Solution (DSS) that will go to the Saltstone Production Facility (SPF). Recent information indicates that solvent entrainment in the DSS is larger than expected. The main concern is with Isopar{reg_sign} L, the diluent in the solvent mixture, and its flammability in the saltstone vault. If it is assumed that all the Isopar{reg_sign} L is released instantaneously into the vault from the curing grout before each subsequent pour, the Isopar{reg_sign} L in the vault headspace is well mixed, and each pour displaces an equivalent volume of headspace, the maximum concentration of Isopar{reg_sign} L in the DSS to assure 25% of the lower flammable limit is not exceeded has been determined to be about 4 ppm. The amount allowed would be higher if the release from grout were significantly less. The Savannah River National Laboratory was tasked with determining the release of Isopar{reg_sign} L from saltstone prepared with a simulated DSS with Isopar{reg_sign} L concentrations ranging from 50 to 200 mg/L in the salt fraction and with test temperatures ranging from ambient to 95 C. The results from the curing of the …
Date: July 31, 2008
Creator: Zamecnik, J; Michael Bronikowski, M; Alex Cozzi, A; Russell Eibling, R & Charles Nash, C
Object Type: Report
System: The UNT Digital Library
Cold Fusion Production and Decay of Neutron-Deficient Isotopes of Dubnium and Development of Extraction Systems for Group V Elements (open access)

Cold Fusion Production and Decay of Neutron-Deficient Isotopes of Dubnium and Development of Extraction Systems for Group V Elements

Excitation functions for the 1n and 2n exit channels of the 208Pb(51V,xn)259-xDb reaction were measured. A maximum cross section of the 1n exit channel of 2070+1100/-760 pb was measured at an excitation energy of 16.0 +- 1.8 MeV. For the 2n exit channel, a maximum cross section of 1660+450/-370 pb was measured at 22.0 +- 1.8 MeV excitation energy. The 1n excitation function for the 209Bi(50Ti,n)258Db reaction was remeasured, resulting in a cross section of 5480+1730/1370 pb at an excitation energy of 16.0 +- 1.6 MeV. Differences in cross section maxima are discussed in terms of the fusion probability below the barrier. The extraction of niobium (Nb) and tantalum (Ta) from hydrochloric acid and mixed hydrochloric acid/lithium chloride media by bis(2-ethylhexyl) hydrogen phosphate (HDEHP) and bis(2-ethylhexyl) hydrogen phosphite (BEHP) was studied. The goal of the experiments was to find a system that demonstrates selectivity among the members of group five of the Periodic Table and is also suitable for the study of dubnium (Db, Z = 105). Experiments with niobium and tantalum were performed with carrier (10-6 M), carrier free (10-10 M) and trace (10-16 M) concentrations of metal using hydrochloric acid solution with concentrations ranging from 1 - 11 …
Date: July 31, 2008
Creator: Gates, Jacklyn M.
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Environmental Biosciences Program Quarterly Report (open access)

Environmental Biosciences Program Quarterly Report

None
Date: July 31, 2008
Creator: Mohr, Lawrence C.
Object Type: Report
System: The UNT Digital Library