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Finish Forty and Home: the Untold World War II Story of B-24s in the Pacific

Access: Use of this item is restricted to the UNT Community
During the early years of World War II in the Pacific theatre, against overwhelming odds, young American airmen flew the longest and most perilous bombing missions of the war. They faced determined Japanese fighters without fighter escort, relentless anti-aircraft fire with no deviations from target, and thousands of miles of over-water flying with no alternative landing sites. Finish Forty and Home is the true story of the men and missions of the 11th Bombardment Group as it fought alone and unheralded in the South Central Pacific, while America had its eyes on the war in Europe. After bombing Nauru, the squadron moves on to bomb Wake Island, Tarawa, and finally Iwo Jima. These missions bring American forces closer and closer to the Japanese home islands and precede the critical American invasions of Tarawa and Iwo Jima. The 42nd Squadron’s losses through 1943 were staggering: 50 out of 110 airmen killed. “Finish Forty and Home is a treasure: poignant, thrilling, and illuminating.”—Laura Hillenbrand, best-selling author of Unbroken and Seabiscuit
Date: August 15, 2011
Creator: Scearce, Phil
Object Type: Book
System: The UNT Digital Library
Small Business Innovation Research: SBA Should Work with Agencies to Improve the Data Available for Program Evaluation (open access)

Small Business Innovation Research: SBA Should Work with Agencies to Improve the Data Available for Program Evaluation

A letter report issued by the Government Accountability Office with an abstract that begins "Federal agencies with a budget of at least $100 million for research and development (R&D) conducted by others must participate in the Small Business Innovation Research (SBIR) program. SBIR has four purposes: meet federal R&D needs; stimulate technological innovation; increase commercialization (e.g., sales) of innovations based on federal R&D; and encourage participation in innovation by small businesses owned by disadvantaged individuals and women. The Small Business Administration (SBA) oversees the efforts of participating agencies, which make awards to small businesses using SBIR funds. Congress directed SBA to develop a database with commercialization data for government use in evaluating the program. GAO was asked to determine (1) how agencies have addressed SBIR's purposes and (2) the extent of data available to evaluate progress in increasing commercialization. GAO analyzed program documents and interviewed officials at SBA and five agencies that accounted for about 96 percent of SBIR awards."
Date: August 15, 2011
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
The National Guard State Partnership Program: Background, Issues, and Options for Congress (open access)

The National Guard State Partnership Program: Background, Issues, and Options for Congress

This report traces the origin and development of the State Partnership Program (SPP), which is a Department of Defense (DOD) security cooperation program run by the National Guard; summarizes its unique aspects; and outlines its statutory basis, funding mechanisms, organization, and activities. It details recent legislative and executive branch actions. It also explores issues that may merit congressional attention and provides options for policymakers who may be interested in modifying the program.
Date: August 15, 2011
Creator: Kapp, Lawrence & Serafino, Nina M.
Object Type: Report
System: The UNT Digital Library
U.S.-Mexican Security Cooperation: The Mérida Initiative and Beyond (open access)

U.S.-Mexican Security Cooperation: The Mérida Initiative and Beyond

Increasing violence perpetrated by drug trafficking organizations and other criminal groups is threatening citizen security and governance in Mexico. Escalating violence has increased U.S. concerns about stability in Mexico, a key political and economic ally, and about the possibility of violence spilling over into the United States. In recent years, U.S.-Mexican security cooperation has increased significantly, largely as a result of the development and implementation of the Mérida Initiative, a counterdrug and anticrime assistance package for Mexico and Central America that was first proposed in October 2007. This report looks at the funding and Congressional oversight for this Initiative.
Date: August 15, 2011
Creator: Ribando Seelke, Clare & Finklea, Kristin M.
Object Type: Report
System: The UNT Digital Library
Texas Attorney General Opinion: GA-0881 (open access)

Texas Attorney General Opinion: GA-0881

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Greg Abbott, regarding a legal question submitted for clarification; Proper method of calculating interest and penalties on the residence homestead of an elderly or disabled person whose property taxes have been deferred under section 33.06 of the Tax Code (RQ-0960-GA)
Date: August 15, 2011
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
Unitarity Constraints on Asymmetric Freeze-In (open access)

Unitarity Constraints on Asymmetric Freeze-In

This paper considers unitarity and CPT constraints on asymmetric freeze-in, the use of freeze-in to store baryon number in a dark sector. In this scenario, Sakharov's out of equilibrium condition is satisfied by placing the visible and hidden sectors at different temperatures while a net visible baryon number is produced by storing negative baryon number in a dark sector. It is shown that unitarity and CPT lead to unexpected cancellations. In particular, the transfer of baryon number cancels completely at leading order. This note has shown that if two sectors are in thermal equilibrium with themselves, but not with each other, then the leading effect transferring conserved quantities between the two sectors is of order the the weak coupling connecting them to the third power. When freeze-in is used to produce a net baryon number density, the leading order effect comes from {Omicron}({lambda}{sup 3}) diagrams where the intermediate state that goes on-shell has a different visible baryon number than the final state visible baryon number. Models in which the correct baryon number is generated with freeze-in as the dominant source of abundance, typically require {lambda} {approx}> 10{sup -6} and m{sub bath} {approx}> TeV. m{sub bath} is the mass of the …
Date: August 15, 2011
Creator: Hook, Anson
Object Type: Article
System: The UNT Digital Library
Built-in and Induced Polarization Across LaAlO3/SrTiO3 Heterojunctions (open access)

Built-in and Induced Polarization Across LaAlO3/SrTiO3 Heterojunctions

Ionic crystals terminated at oppositely charged polar surfaces are inherently unstable and expected to undergo surface reconstructions to maintain electrostatic stability. Essentially, an electric field that arises between oppositely charged atomic planes gives rise to a built-in potential that diverges with thickness. Here we present evidence of such a built-in potential across polar LaAlO{sub 3} thin films grown on SrTiO{sub 3} substrates, a system well known for the electron gas that forms at the interface. By performing tunneling measurements between the electron gas and metallic electrodes on LaAlO{sub 3} we measure a built-in electric field across LaAlO{sub 3} of 80.1 meV/{angstrom}. Additionally, capacitance measurements reveal the presence of an induced dipole moment across the heterostructure. We forsee use of the ionic built-in potential as an additional tuning parameter in both existing and novel device architectures, especially as atomic control of oxide interfaces gains widespread momentum.
Date: August 15, 2011
Creator: Guneeta, Singh-Bhalla
Object Type: Article
System: The UNT Digital Library
Theory of Two-Magnon Raman Scattering in Iron Pnictides and Chalcogenides (open access)

Theory of Two-Magnon Raman Scattering in Iron Pnictides and Chalcogenides

Although the parent iron-based pnictides and chalcogenides are itinerant antiferromagnets, the use of local moment picture to understand their magnetic properties is still widespread. We study magnetic Raman scattering from a local moment perspective for various quantum spin models proposed for this new class of superconductors. These models vary greatly in the level of magnetic frustration and show a vastly different two-magnon Raman response. Light scattering by two-magnon excitations thus provides a robust and independent measure of the underlying spin interactions. In accord with other recent experiments, our results indicate that the amount of magnetic frustration in these systems may be small.
Date: August 15, 2011
Creator: Chen, C. C.
Object Type: Article
System: The UNT Digital Library
ADDING REALISM TO NUCLEAR MATERIAL DISSOLVING ANALYSIS (open access)

ADDING REALISM TO NUCLEAR MATERIAL DISSOLVING ANALYSIS

Two new criticality modeling approaches have greatly increased the efficiency of dissolver operations in H-Canyon. The first new approach takes credit for the linear, physical distribution of the mass throughout the entire length of the fuel assembly. This distribution of mass is referred to as the linear density. Crediting the linear density of the fuel bundles results in using lower fissile concentrations, which allows higher masses to be charged to the dissolver. Also, this approach takes credit for the fact that only part of the fissile mass is wetted at a time. There are multiple assemblies stacked on top of each other in a bundle. On average, only 50-75% of the mass (the bottom two or three assemblies) is wetted at a time. This means that only 50-75% (depending on operating level) of the mass is moderated and is contributing to the reactivity of the system. The second new approach takes credit for the progression of the dissolving process. Previously, dissolving analysis looked at a snapshot in time where the same fissile material existed both in the wells and in the bulk solution at the same time. The second new approach models multiple consecutive phases that simulate the fissile material …
Date: August 15, 2011
Creator: Williamson, B.
Object Type: Article
System: The UNT Digital Library
FINAL PROJECT REPORT: A Geophysical Characterization & Monitoring Strategy for Determining Hydrologic Processes in the Hyporheic Corridor at the Hanford 300-Area (open access)

FINAL PROJECT REPORT: A Geophysical Characterization & Monitoring Strategy for Determining Hydrologic Processes in the Hyporheic Corridor at the Hanford 300-Area

The primary objective of this research was to advance the prediction of solute transport between the Uranium contaminated Hanford aquifer and the Columbia River at the Hanford 300 Area by improving understanding of how fluctuations in river stage, combined with subsurface heterogeneity, impart spatiotemporal complexity to solute exchange along the Columbia River corridor. Our work explored the use of continuous waterborne electrical imaging (CWEI), in conjunction with fiber-optic distributed temperature sensor (FO-DTS) and time-lapse resistivity monitoring, to improve the conceptual model for how groundwater/surface water exchange regulates uranium transport. We also investigated how resistivity and induced polarization can be used to generate spatially rich estimates of the variation in depth to the Hanford-Ringold (H-R) contact between the river and the 300 Area Integrated Field Research Challenge (IFRC) site. Inversion of the CWEI datasets (a data rich survey containing ~60,000 measurements) provided predictions of the distributions of electrical resistivity and polarizability, from which the spatial complexity of the primary hydrogeologic units along the river corridor was reconstructed. Variation in the depth to the interface between the overlying coarse-grained, high permeability Hanford Formation and the underlying finer-grained, less permeable Ringold Formation, an important contact that limits vertical migration of contaminants, has been …
Date: August 15, 2011
Creator: Slater, Lee
Object Type: Report
System: The UNT Digital Library
Building Toxic Metal Characterization and Decontamination Report: Area 6, Building 914 (open access)

Building Toxic Metal Characterization and Decontamination Report: Area 6, Building 914

The purpose of this report is to outline the toxic metal characterization and decontamination efforts in Area 6, Building 914. This includes the initial building inspection, the hotspot sampling, results/findings, building cleanup, and the verification sampling. Building 914 is a steel light frame building that was constructed in 1992. It is about 16,454 square feet, and five employees are assigned to this building. According to the building's floor plan blueprints, it could be inferred that this building was once a Wiremen/Lineman shop. In 2002-2004, the National Nuclear Security Administration Nevada Site Office embarked on a broad characterization of beryllium (Be) surface concentrations throughout the North Las Vegas Facility, the Nevada National Security Site (NNSS), and ancillary facilities like the Special Technologies Laboratory, Remote Sensing Laboratory, etc. Building 914 was part of this characterization. The results of the 2002 study illustrated that the metal housekeeping limits were within acceptable limits and from a Be standpoint, the building was determined to be fit for occupancy. On March 2, 2011, based on a request from Building 914 users, National Security Technologies, LLC (NSTec) Industrial Hygiene (IH) collected bulk samples from the southwest corner of Building 914 at heights above 6 feet where black …
Date: August 15, 2011
Creator: Hygiene, NSTec Industrial
Object Type: Report
System: The UNT Digital Library
Dissecting the Wjj Anomaly: Diagnostic Tests of a Leptophobic Z' (open access)

Dissecting the Wjj Anomaly: Diagnostic Tests of a Leptophobic Z'

We examine the scenario where a leptophobic Z{prime} boson accounts for the excess of events in the Wjj channel as observed by CDF. We assume generation independent couplings for the Z{prime} and obtain allowed regions for the four hadronic couplings using the measured cross section as well as constraints from dijet production at UA2. These coupling regions translate into well-determined rates for the associated production of Z/{gamma} + Z{prime} at the Tevatron and LHC, as well as W + Z{prime} at the LHC,that are directly correlated with the Wjj rate observed at the Tevatron. The Wjj rate at the LHC is large and this channel should be observed soon once the SM backgrounds are under control. The rates for Z/{gamma} + Z{prime} associated production are smaller, and these processes should not yet have been observed at the Tevatron given the expected SM backgrounds. In addition, we show that more coupling information is obtainable from the M{sub WZ{prime}} distribution. Once detected, these processes will provide further valuable information on the Z{prime} boson couplings.
Date: August 15, 2011
Creator: Hewett, J. L. & Rizzo, T. G.
Object Type: Article
System: The UNT Digital Library
Phase-field investigation on the non-equilibrium interface dynamics of rapid alloy solidification (open access)

Phase-field investigation on the non-equilibrium interface dynamics of rapid alloy solidification

The research program reported here is focused on critical issues that represent conspicuous gaps in current understanding of rapid solidification, limiting our ability to predict and control microstructural evolution (i.e. morphological dynamics and microsegregation) at high undercooling, where conditions depart significantly from local equilibrium. More specifically, through careful application of phase-field modeling, using appropriate thin-interface and anti-trapping corrections and addressing important details such as transient effects and a velocity-dependent (i.e. adaptive) numerics, the current analysis provides a reasonable simulation-based picture of non-equilibrium solute partitioning and the corresponding oscillatory dynamics associated with single-phase rapid solidification and show that this method is a suitable means for a self-consistent simulation of transient behavior and operating point selection under rapid growth conditions. Moving beyond the limitations of conventional theoretical/analytical treatments of non-equilibrium solute partitioning, these results serve to substantiate recent experimental findings and analytical treatments for single-phase rapid solidification. The departure from the equilibrium solid concentration at the solid-liquid interface was often observed during rapid solidification, and the energetic associated non-equilibrium solute partitioning has been treated in detail, providing possible ranges of interface concentrations for a given growth condition. Use of these treatments for analytical description of specific single-phase dendritic and cellular operating point …
Date: August 15, 2011
Creator: Choi, Jeong
Object Type: Thesis or Dissertation
System: The UNT Digital Library
New Dualities in Supersymmetric Chiral Gauge Theories (open access)

New Dualities in Supersymmetric Chiral Gauge Theories

We analyze the phase structure of supersymmetric chiral gauge theories with gauge group SU(N), an antisymmetric, and F {le} N + 3 flavors, in the presence of a cubic superpotential. When F = N + 3 the theory flows to a superconformal fixed point in the infrared, and new dual descriptions of this theory are uncovered. The theory with odd N admits a self-dual magnetic description. For general N, we find an infinite family of magnetic dual descriptions, characterized by arbitrarily large gauge groups and additional classical global symmetries that are truncated by nonperturbative effects. The infrared dynamics of these theories are analyzed using a-maximization, which supports the claim that all these theories flow to the same superconformal fixed point. A very rich phase structure is found when the number of flavors is reduced below N + 3, including a new self-dual point, transitions from conformal to confining, and a nonperturbative instability for F {le} N. We also give examples of chiral theories with antisymmetrics that have nonchiral duals.
Date: August 15, 2011
Creator: Craig, Nathaniel; /Princeton, Inst. Advanced Study /Rutgers U., Piscataway; Essig, Rouven; Hook, Anson; Torroba, Gonzalo & /Stanford U., Phys. Dept. /SLAC
Object Type: Article
System: The UNT Digital Library
Examining Uncertainty in Demand Response Baseline Models and Variability in Automated Response to Dynamic Pricing (open access)

Examining Uncertainty in Demand Response Baseline Models and Variability in Automated Response to Dynamic Pricing

Controlling electric loads to deliver power system services presents a number of interesting challenges. For example, changes in electricity consumption of Commercial and Industrial (C&I) facilities are usually estimated using counterfactual baseline models, and model uncertainty makes it difficult to precisely quantify control responsiveness. Moreover, C&I facilities exhibit variability in their response. This paper seeks to understand baseline model error and demand-side variability in responses to open-loop control signals (i.e. dynamic prices). Using a regression-based baseline model, we define several Demand Response (DR) parameters, which characterize changes in electricity use on DR days, and then present a method for computing the error associated with DR parameter estimates. In addition to analyzing the magnitude of DR parameter error, we develop a metric to determine how much observed DR parameter variability is attributable to real event-to-event variability versus simply baseline model error. Using data from 38 C&I facilities that participated in an automated DR program in California, we find that DR parameter errors are large. For most facilities, observed DR parameter variability is likely explained by baseline model error, not real DR parameter variability; however, a number of facilities exhibit real DR parameter variability. In some cases, the aggregate population of C&I …
Date: August 15, 2011
Creator: Mathieu, Johanna L.; Callaway, Duncan S. & Kiliccote, Sila
Object Type: Article
System: The UNT Digital Library
Evaluation of the Impact of the Defense Waste Processing Facility (DWPF) Laboratory Germanium Oxide Use on Recycle Transfers to the H-Tank Farm (open access)

Evaluation of the Impact of the Defense Waste Processing Facility (DWPF) Laboratory Germanium Oxide Use on Recycle Transfers to the H-Tank Farm

When processing High Level Waste (HLW) glass, the Defense Waste Processing Facility (DWPF) cannot wait until the melt or waste glass has been made to assess its acceptability, since by then no further changes to the glass composition and acceptability are possible. Therefore, the acceptability decision is made on the upstream feed stream, rather than on the downstream melt or glass product. This strategy is known as 'feed forward statistical process control.' The DWPF depends on chemical analysis of the feed streams from the Sludge Receipt and Adjustment Tank (SRAT) and the Slurry Mix Evaporator (SME) where the frit plus adjusted sludge from the SRAT are mixed. The SME is the last vessel in which any chemical adjustments or frit additions can be made. Once the analyses of the SME product are deemed acceptable, the SME product is transferred to the Melter Feed Tank (MFT) and onto the melter. The SRAT and SME analyses have been analyzed by the DWPF laboratory using a 'Cold Chemical' method but this dissolution did not adequately dissolve all the elemental components. A new dissolution method which fuses the SRAT or SME product with cesium nitrate (CsNO{sub 3}), germanium (IV) oxide (GeO{sub 2}) and cesium …
Date: August 15, 2011
Creator: Jantzen, Carol M. & Laurinat, J. E.
Object Type: Report
System: The UNT Digital Library
Top Quark Anomalous Couplings at the International Linear Collider (open access)

Top Quark Anomalous Couplings at the International Linear Collider

We present a study of the experimental determination of the forward-backward asymmetry in the process e{sup +}e{sup -} {yields} t{bar t} and in the subsequent t {yields} Wb decay, studied in the context of the International Linear Collider. This process probes the elementary couplings of the top quark to the photon, the Z and the W bosons at a level of precision that is difficult to achieve at hadron colliders. Measurement of the forward-backward asymmetry requires excellent b quark identification and determination of the quark charge. The study reported here is performed in the most challenging all-hadronic channel e{sup +}e{sup -} {yields} b{bar b}q{bar q}q{bar q}. It includes realistic details of the experimental environment, a full Monte Carlo simulation of the detector, based on the Silicon Detector concept, and realistic event reconstruction. The forward-backward asymmetries are determined to a precision of approximately 1% for each of two choices of beam polarization. We analyze the implications for the determination of the t{bar t}Z and Wt{bar b} couplings.
Date: August 15, 2011
Creator: Devetak, Erik; Nomerotski, Andrei & Peskin, Michael
Object Type: Article
System: The UNT Digital Library
Where the Sidewalk Ends: Jets and Missing Energy Search Strategies for the 7 TeV LHC (open access)

Where the Sidewalk Ends: Jets and Missing Energy Search Strategies for the 7 TeV LHC

This work explores the potential reach of the 7 TeV LHC to new colored states in the context of simplified models and addresses the issue of which search regions are necessary to cover an extensive set of event topologies and kinematic regimes. This article demonstrates that if searches are designed to focus on specific regions of phase space, then new physics may be missed if it lies in unexpected corners. Simple multiregion search strategies can be designed to cover all of kinematic possibilities. A set of benchmark models are created that cover the qualitatively different signatures and a benchmark multiregion search strategy is presented that covers these models.
Date: August 15, 2011
Creator: Alves, Daniele S.M.; Izaguirre, Eder; Wacker, Jay G. & /SLAC /Stanford U., ITP
Object Type: Article
System: The UNT Digital Library
Searches for Rare or Forbidden Semileptonic Charm Decays (open access)

Searches for Rare or Forbidden Semileptonic Charm Decays

We present searches for rare or forbidden charm decays of the form X{sub c}{sup +} {yields} h{sup {+-}}{ell}{sup {-+}}{ell}{sup ({prime})+}, where X{sub c}{sup +} is a charm hardron (D{sup +}, D{sub s}{sup +}, or {Lambda}{sub c}{sup +}), h{sup {+-}} is a pion, kaon, or proton, and {ell}{sup ({prime}){+-}} is an electron or muon. The analysis is based on 384 fb{sup -1} of e{sup +}e{sup -} annihilation data collected at or close to the {Upsilon}(4S) resonance with the BABAR detector at the SLAC National Accelerator Laboratory. No significant signal is observed for any of the 35 decay modes that are investigated. We establish 90% confidence-level upper limits on the branching fractions between 1 x 10{sup -6} and 44 x 10{sup -6} depending on the channel. In most cases, these results represent either the first limits or significant improvements on existing limits for the decay modes studied.
Date: August 15, 2011
Creator: Lees, J.P.
Object Type: Article
System: The UNT Digital Library
Towards a Holographic Marginal Fermi Liquid (open access)

Towards a Holographic Marginal Fermi Liquid

We present an infinite class of 2+1 dimensional field theories which, after coupling to semi-holographic fermions, exhibit strange metallic behavior in a suitable large N limit. These theories describe lattices of hypermultiplet defects interacting with parity-preserving supersymmetric Chern-Simons theories with U(N) x U(N) gauge groups at levels {+-}k. They have dual gravitational descriptions in terms of lattices of probe M2 branes in AdS{sub 4} x S{sup 7}/Z{sub k} (for N >> 1,N >> k{sup 5}) or probe D2 branes in AdS{sub 4} x CP{sup 3} (for N >> k >> 1,N << k{sup 5}). We discuss several challenges one faces in maintaining the success of these models at finite N, including backreaction of the probes in the gravity solutions and radiative corrections in the weakly coupled field theory limit.
Date: August 15, 2011
Creator: Jensen, Kristan; Kachru, Shamit; Karch, Andreas; Polchinski, Joseph & Silverstein, Eva
Object Type: Article
System: The UNT Digital Library
Doping Dependence of the $(\pi,\pi)$ Shadow Band in La-Based Cuprates Studied by Angle-Resolved Photoemission Spectroscopy (open access)

Doping Dependence of the $(\pi,\pi)$ Shadow Band in La-Based Cuprates Studied by Angle-Resolved Photoemission Spectroscopy

The ({pi},{pi}) shadow band (SB) in La-based cuprate family (La214) was studied by angle-resolved photoemission spectroscopy (ARPES) over a wide doping range from x = 0.01 to x = 0.25. Unlike the well-studied case of the Bi-based cuprate family, an overall strong, monotonic doping dependence of the SB intensity at the Fermi level (E{sub F}) was observed. In contrast to a previous report for the presence of the SB only close to x = 1/8, we found it exists in a wide doping range, associated with a doping-independent ({pi},{pi}) wave vector but strongly doping-dependent intensity: It is the strongest at x {approx} 0.03 and systematically diminishes as the doping increases until it becomes negligible in the overdoped regime. This SB with the observed doping dependence of intensity can in principle be caused by the antiferromagnetic fluctuations or a particular form of low-temperature orthorhombic lattice distortion known to persist up to x {approx} 0.21 in the system, with both being weakened with increasing doping. However, a detailed binding energy dependent analysis of the SB at x = 0.07 does not appear to support the former interpretation, leaving the latter as a more plausible candidate, despite a challenge in quantitatively linking the …
Date: August 15, 2011
Creator: Shen, Z. X.
Object Type: Article
System: The UNT Digital Library
A transilient matrix for moist convection (open access)

A transilient matrix for moist convection

A method is introduced for diagnosing a transilient matrix for moist convection. This transilient matrix quantifies the nonlocal transport of air by convective eddies: for every height z, it gives the distribution of starting heights z{prime} for the eddies that arrive at z. In a cloud-resolving simulation of deep convection, the transilient matrix shows that two-thirds of the subcloud air convecting into the free troposphere originates from within 100 m of the surface. This finding clarifies which initial height to use when calculating convective available potential energy from soundings of the tropical troposphere.
Date: August 15, 2011
Creator: Romps, D. & Kuang, Z.
Object Type: Article
System: The UNT Digital Library
Persistence of soil organic matter as an ecosystem property (open access)

Persistence of soil organic matter as an ecosystem property

Globally, soil organic matter (SOM) contains more than three times as much carbon as either the atmosphere or terrestrial vegetation. Yet it remains largely unknown why some SOM persists for millennia whereas other SOM decomposes readily—and this limits our ability to predict how soils will respond to climate change. Recent analytical and experimental advances have demonstrated that molecular structure alone does not control SOM stability: in fact, environmental and biological controls predominate. Here we propose ways to include this understanding in a new generation of experiments and soil carbon models, thereby improving predictions of the SOM response to global warming.
Date: August 15, 2011
Creator: Schmidt, M.W.; Torn, M. S.; Abiven, S.; Dittmar, T.; Guggenberger, G.; Janssens, I.A. et al.
Object Type: Article
System: The UNT Digital Library

[Helen Snapp Wearing Uniform]

Photograph of Helen Snapp gazing off camera. She wears a Santiago Blue uniform and holds the Gold Congressional Medal around her neck.
Date: August 15, 2011
Creator: unknown
Object Type: Photograph
System: The Portal to Texas History