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Microstructural evolution in fast-neutron-irradiated austenitic stainless steels (open access)

Microstructural evolution in fast-neutron-irradiated austenitic stainless steels

The present work has focused on the specific problem of fast-neutron-induced radiation damage to austenitic stainless steels. These steels are used as structural materials in current fast fission reactors and are proposed for use in future fusion reactors. Two primary components of the radiation damage are atomic displacements (in units of displacements per atom, or dpa) and the generation of helium by nuclear transmutation reactions. The radiation environment can be characterized by the ratio of helium to displacement production, the so-called He/dpa ratio. Radiation damage is evidenced microscopically by a complex microstructural evolution and macroscopically by density changes and altered mechanical properties. The purpose of this work was to provide additional understanding about mechanisms that determine microstructural evolution in current fast reactor environments and to identify the sensitivity of this evolution to changes in the He/dpa ratio. This latter sensitivity is of interest because the He/dpa ratio in a fusion reactor first wall will be about 30 times that in fast reactor fuel cladding. The approach followed in the present work was to use a combination of theoretical and experimental analysis. The experimental component of the work primarily involved the examination by transmission electron microscopy of specimens of a model …
Date: December 1, 1987
Creator: Stoller, R.E.
System: The UNT Digital Library
Development of a current collection loss management system for SDI homopolar power supplies (open access)

Development of a current collection loss management system for SDI homopolar power supplies

High speed, high power density current collection systems have been identified as an enabling technology required to construct homopolar power supplies to meet SDI missions. This work is part of a three-year effort directed towards the analysis, experimental verification, and prototype construction of a current collection system designed to operated continuously at 2 kA/cm{sup 2}, at a rubbing speed of 200 m/s, and with acceptable losses in a space environment. To data, no system has achieved these conditions simultaneously. This is the annual report covering the first year period of performance on DOE contract DE-AC03-86SF16518. Major areas covered include design and construction of a cryogenically-cooled brush test rig, design of a high speed brush test rig, loss analysis of the current collection system, and an application study which defines the air core homopolar construction necessary to achieve the goal of 80--90 kW/kg generator power density. 15 figs.
Date: January 1, 1987
Creator: Hannan, W.F. III.
System: The UNT Digital Library
2-Dimensional studies of the disk-and-washer and side-coupled resonant cavity structures (open access)

2-Dimensional studies of the disk-and-washer and side-coupled resonant cavity structures

The work done consists of three parts: optimizing the disk-and-washer (DAW) structure at ..beta.. = 0.5662 corresponding to E = 200 MeV; comparing the DAW structure with the side-coupled (SCS) structure at various values of beta, ranging from ..beta.. = 0.4569 and E = 116 MeV to ..beta.. = 0.7131 and E = 400 MeV; and re-optimizing the DAW structure at ..beta.. = 0.7131. 4 refs., 51 figs., 41 tabs.
Date: December 1, 1987
Creator: Larry, L.D. Jr.
System: The UNT Digital Library
(Support of the board on ocean science and policy) (open access)

(Support of the board on ocean science and policy)

The National Academy of Sciences, through the Ocean Studies Board of the Commission on Physical Sciences, Mathematics and Resources, proposes to provide guidance on major ocean sciences and policy issues to the National Oceanic and Atmospheric Administration, the National Science Foundation, the Department of the Navy, the US Geological Survey, the Minerals Management Service of the Department of the Interior, the US Coast Guard, the Department of State, the Department of Energy, The Environmental Protection Agency, and the National Aeronautics and Space Administration. The work plan for this activity is presented in the program plan section of this proposal. Work plans for subsequent years will be submitted prior to the commencement of work. Financial support is requested for continued support of the Ocean Studies Board activities from 1 June 1987 through 31 May 1989. Funds in the amount of $513,400 are requested for the period 1 June 1987 through 31 May 1988, as indicated in the attached estimate of costs.
Date: January 1, 1987
Creator: unknown
System: The UNT Digital Library
Teratology studies of lewisite and sulfur mustard agents: Effects of lewisite in rats and rabbits: Final report (open access)

Teratology studies of lewisite and sulfur mustard agents: Effects of lewisite in rats and rabbits: Final report

Lewisite was administered to rats and rabbits by intragastric intubation. Maternal animals were weighed periodically, and, at necropsy (20 dg (days of gestation) in rats and 30 dg in rabbits), were examined for gross lesions of major organs and reproductive performances; live fetuses were weighed and examined for external, internal and skeletal defect. In rats, a dose level of 1.5 mg/kg did not induce toxic or teratogenic responses in maternal and fetal body weights and a significant reduction in the number if viable fetuses were evident. In rabbit studies maternal mortality occurred in all but one of the lewisite treatment groups and ranged from 13% to 100% at dose levels of 0.07 and 1.5 mg/kg, respectively. This mortality rate limited the sample size and impaired the detection of statistical significance among treatments. However, at the lowest dose level of the teratology study (0.07 mg/kg, maternal mortality was the only indicator of lewisite toxicity; at the highst dose (0.6 mg/kg), significant findings included 86% maternal mortality, a decrease in maternal body weight gains and an increase in the incidence of fetal stunting, although only a tendency in decreased fetal body weights was observed. These results suggest that maternal mortality was the …
Date: December 31, 1987
Creator: Hackett, P L; Sasser, L B; Rommereim, R L; Cushing, J A; Buschbom, R L & Kalkwarf, D R
System: The UNT Digital Library
The effects of halides on the performance of coal gas-fueled molten carbonate fuel cells: Final report, October 1986-October 1987 (open access)

The effects of halides on the performance of coal gas-fueled molten carbonate fuel cells: Final report, October 1986-October 1987

This report presents the results of a program to determine the probable tolerable limits of hydrogen chloride and hydrogen fluoride present in the fuel and oxidant streams of molten carbonate fuel cells that are operating on gasified coal. A literature survey and thermodynamic analyses were performed to determine the likely effects of halides on cell performance and materials. Based on the results of these studies, accelerated corrosion experiments and electrode half-cell performance tests were conducted using electrolyte which contained chloride and fluoride. These data and the results of previous in-cell tests were used to develop a computer for predicting the performance decay due to these halides. The tolerable limits were found to be low (less than 1 PPM) and depend on the power plant system configuration, the operating conditions of the fuel cell stack, the cell design and initial electrolyte inventory, and the ability of the cell to scrub low levels of halide from the reactant streams. The primary decay modes were conversion of the electrolyte from pure carbonate to a carbonate-halide mixture and accelerated electrolyte evaporation. 75 figs., 16 tabs.
Date: October 1, 1987
Creator: Magee, T. P.; Kunz, H. R.; Krasij, M. & Cote, H. A.
System: The UNT Digital Library
Kinetics of coal pyrolysis and devolatilization (open access)

Kinetics of coal pyrolysis and devolatilization

Research continued an coal pyrolysis and devolatilization. An experimentally based, conceptual model of the devolatilization of a HV bituminous coal is outlined in this repair. This model contends that the relative dominance of a process type-chemical kinetic, heat transport, mass transport -- varies with the extent of reaction for a given set of heating conditions and coal type and with experimental and with experimental conditions for a given coal types and extent of reaction. The relevant reference'' conditions of interest for direct utilization are rapid transient heating of small (< 100 micron) particles to temperatures of 1000{degrees}C or greater. The model postulatew that the overall rates of coal devolatilization should vary with coal type insofar as the characteristics of the parent coal determine the potential tar yield and the chemical characteristics of the initial tars. Experimental evidence indicates chemical characteristics and yields of primary'' tars vary significant with coal type. Consequently, the conceptual model would indicate a shift from transport to chemical dominance of rate processes with variation in coal types. Using the conceptual model, UTRC has been able to correlate initial mass loss with a heat transfer index for a wide range of conditions for high tar yielding coals. …
Date: January 1, 1987
Creator: unknown
System: The UNT Digital Library
Kinetics of coal pyrolysis and devolatilization (open access)

Kinetics of coal pyrolysis and devolatilization

An experimentally based, conceptual model of the devolatilization of a HV bituminous coal is outlined in this report. This model contends that the relative dominance of a process type-chemical kinetic, heat transport, mass transport -- varies with the extent of reaction for a given set of heating conditions and coal type and with experimental conditions for a given coal type and extent of reaction. The rate of devolatilization mass loss process is dominated initially by heat transfer processes, then coupled mass transfer and chemical kinetics, and finally by chemical processes alone. However, the chemical composition of the initial tars are determined primarily by the chemical characteristics of the parent coal. Chemically controlled gas phase reactions of the initial tars and coupled mass transfer and chemically controlled reactions of heavy tars determine the bulk of the light gas yields. For a HV bituminous coal this conceptual model serves to quantify the Two-Component Hypothesis'' of volatiles evolution. The model postulates that the overall rates of coal devolatilization should vary with coal type insofar as the characteristics of the parent coal determine the potential tar yield and the chemical characteristics of the initial tars. Experimental evidence indicates chemical characteristics and yields of primary'' …
Date: January 1, 1987
Creator: unknown
System: The UNT Digital Library
Combustion of ultrafine coal/water mixtures and their application in gas turbines: Final report (open access)

Combustion of ultrafine coal/water mixtures and their application in gas turbines: Final report

The feasibility of using coal-water fuels (CWF) in gas turbine combustors has been demonstrated in recent pilot plant experiments. The demands of burning coal-water fuels with high flame stability, complete combustion, low NO/sub x/ emission and a resulting fly ash particle size that will not erode turbine blades represent a significant challenge to combustion scientists and engineers. The satisfactory solution of these problems requires that the variation of the structure of CWF flames, i.e., the fields of flow, temperature and chemical species concentration in the flame, with operating conditions is known. Detailed in-flame measurements are difficult at elevated pressures and it has been proposed to carry out such experiments at atmospheric pressure and interpret the data by means of models for gas turbine combustor conditions. The research was carried out in five sequential tasks: cold flow studies; studies of conventional fine-grind CWF; combustion studies with ultrafine CWF fuel; reduction of NO/sub x/ emission by staged combustion; and data interpretation-ignition and radiation aspects. 37 refs., 61 figs., 9 tabs.
Date: October 1, 1987
Creator: Toqan, M.A.; Srinivasachar, S.; Staudt, J.; Varela, F. & Beer, J.M.
System: The UNT Digital Library
Dislocation-hydrogen correlation in metals (open access)

Dislocation-hydrogen correlation in metals

We present a method using SANS experiments to measure correlation between dislocations and absorbed hydrogen in metals. The technique involves sequential measurements first on a metal with dislocation networks, then two further measurements on the same sample infused with deuterium and normal hydrogen. SANS experiments on metals with dislocations networks have been performed a number of times and some results have appeared in the literature. We have computer estimates of the contribution of absorbed hydrogen and deuterium to SANS cross sections. The results show that we can expect to see the hydrogen contribution in the SANS cross section and see any possible correlations of the hydrogen positions and the dislocations. 8 refs., 2 figs., 2 tabs.
Date: November 1, 1987
Creator: Summerfield, G.C.; King, J.S.; Heuser, B.; Epperson, J.E. (Michigan Univ., Ann Arbor, MI (USA). Dept. of Nuclear Engineering & Argonne National Lab., IL (USA))
System: The UNT Digital Library
Geothermal investigations in Idaho: Geothermal resource analysis in Twin Falls County, Idaho: (open access)

Geothermal investigations in Idaho: Geothermal resource analysis in Twin Falls County, Idaho:

Increased utilization of the geothermal resource in the Twin Falls - Banbury area of southern Idaho has resulted in noticeable declines in the artesian head of the system. In order to determine the nature of the declines, a network of wells was identified for monitoring shut-in pressures and temperatures. In addition, a compilation of data and reconnaissance of the areal geology was undertaken in order to better understand the geologic framework and its relationship to the occurrence of the thermal waters in the system. The results of the monitoring indicate that while water temperatures have remained constant, the system shows a gradual overall decline in artesian pressure superimposed on fluctuations caused by seasonal use of the system. Well testing and the similarity of hydrographs resulting from well monitoring throughout the area suggest that there are no major hydrologic barriers to thermal water movement in the system and that wells are affected by increases and decreases in utilization of nearby wells. 46 refs., 13 figs., 1 tab.
Date: July 1, 1987
Creator: Street, L.V. & DeTar, R.E.
System: The UNT Digital Library
300 Area Process Trench Sediment Analysis Report (open access)

300 Area Process Trench Sediment Analysis Report

This report describes the results of a sampling program for the sediments underlying the Process Trenches serving the 300 Area on the Hanford reservation. These Process Trenches were the subject of a Closure Plan submitted to the Washington State Department of Ecology and to the US Environmental Protection Agency in lieu of a Part B permit application on November 8, 1985. The closure plan described a proposed sampling plan for the underlying sediments and potential remedial actions to be determined by the sample analyses results. The results and proposed remedial action plan are presented and discussed in this report. 50 refs., 6 figs., 8 tabs.
Date: December 1, 1987
Creator: Zimmerman, M.G. & Kossik, C.D.
System: The UNT Digital Library
Gamma-ray decay of levels in /sup 53/Cr (open access)

Gamma-ray decay of levels in /sup 53/Cr

Gamma-ray decay of levels in the stable isotope /sup 53/Cr has been studied using /sup 53/Cr(n,n'..gamma..) reactions for incident neutron energies between threshold and 10 MeV. Of the 65 gamma rays or gamma-ray groups observed for neutron interactions with /sup 53/Cr, 50 have been placed or tentatively placed among 34 levels in /sup 53/Cr up to an excitation energy of 4.36 MeV. Deduced branching ratios are in reasonable agreement with previous measurements except for decay of the E/sub x/ = 1537-keV level. For the decay of the E/sub x/ = 1537-keV level we are unable to explain variations in the branching ratios of the transition gamma rays as a function of incident neutron energy within the framework of the presently known level structure of /sup 53/Cr and suggest the possibility of a second energy level at E/sub x/ = 1537 keV. 59 refs., 13 figs., 2 tabs.
Date: November 1, 1987
Creator: Dickens, J.K. & Larson, D.C.
System: The UNT Digital Library
Enhanced durability and reactivity for zinc ferrite desulfurization sorbent (open access)

Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

AMAX Research Development Center (AMAX R D) has been investigating methods for improving the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hog coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. The reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point in a bench-scale fixed-bed reactor. The durability may be defined as the ability of the sorbent to maintain its reactivity and other important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and regeneration. Two base case sorbents, spherical pellets and cylindrical extrudes used in related METC sponsored projects, are being used to provide a basis for the comparison of physical characteristics and chemical reactivity.
Date: October 27, 1987
Creator: Jha, M. C. & Berggren, M. H.
System: The UNT Digital Library
Simulated seismic event release fraction data: Progress report, April 1986-April 1987 (open access)

Simulated seismic event release fraction data: Progress report, April 1986-April 1987

The object of this project is to obtain experimental data on the release of airborne particles during seismic events involving plutonium handling facilities. In particular, cans containing plutonium oxide powder may be involved and some of the powder may become airborne. No release fraction data for such scenarios are available and risk assessment calculations for such events lacked specificity describing the physical processes involved. This study has provided initial data based on wind tunnel tests simulating the impact of the debris on simulated cans of plutonium oxide powder. The release fractions are orders of magnitude smaller than previously available estimates. 8 refs., 3 figs., 2 tabs.
Date: November 15, 1987
Creator: Langer, G. & Deitesfeld, C. A.
System: The UNT Digital Library
TIBER II/ETR final design report: Volume 1, 1. 0 Introduction; 2. 0 plasma engineering (open access)

TIBER II/ETR final design report: Volume 1, 1. 0 Introduction; 2. 0 plasma engineering

This paper discusses the design of the TIBER II tokamak test reactor. Specific topics discussed are the physics objectives for Tiber, magnetics, baseline operating point, pulsed inductive operation, edge physics and impurity control, fueling, disruption control, vertical stability and impurity flow reversal. (LSP)
Date: September 1, 1987
Creator: Lee, J.D. (ed.)
System: The UNT Digital Library
Organic Rankine-cycle power systems working fluids study: Topical report No. 2, Toluene (open access)

Organic Rankine-cycle power systems working fluids study: Topical report No. 2, Toluene

The US Department of Energy initiated an investigation at Argonne National Laboratory in 1982 to experimentally determine the thermal stability limits and degradation rates of toluene as a function of maximum cycle temperature. Following the design and construction of a dynamic test loop capable of closely simulating the thermodynamic conditions of typical organic Rankine-cycle (ORC) power systems, four test runs, totaling about 3900 h of test time and covering a temperature range of 600-677(degree)F, were completed. Both liquid and noncondensable-vapor (gaseous) samples were drawn periodically and analyzed using capillary-column gas chromatography, gas chromatography/mass spectrometry, and mass spectrometry. A computer program that can predict degradation in an ORC engine was developed. Experimental results indicate that, if oxygen can be excluded from the system, toluene is a stable fluid up to the maximum test temperature; the charge of toluene could be used for several years before replacement became necessary. (Additional data provided by Sundstrand Corp. from tests sponsored by the National Aeronautics and Space Administration indicate that toluene may be used at temperatures up to 750(degree)F.) Degradation products are benign; the main liquid degradation products are bibenzyls, and the main gaseous degradation products are hydrogen and methane. A cold trap to remove …
Date: February 1, 1987
Creator: Cole, R.L.; Demirgian, J.C. & Allen, J.W.
System: The UNT Digital Library
Economic Decision Making Model for Geothermal Sludge Disposal alternatives (EDM-GSD): Version 1. 0 (open access)

Economic Decision Making Model for Geothermal Sludge Disposal alternatives (EDM-GSD): Version 1. 0

The Economic Decision Making Model for Geothermal Sludge Disposal Alternatives-Version 1.0'' (EDM-GSD 1.0) is a microcomputer-based dynamic model developed to assist in determining the benefits and costs of various geothermal solid waste treatment procedures. It is intended for use by geothermal managers in dealing with geothermal waste and treatment process issues as a means to assist in overcoming the technical and economic barriers to expanded geothermal energy utilization. The model is based on a 50MW flash plant. However, it is designed to provide the user with sufficient flexibility when inputing data to analyze all types of geothermal plants. Default values for economic and technical parameters can be overridden by the user through the input of specific data. In addition, data can be changed for any year of an analysis to account for desired changes in input parameters such as costs and distance to disposal sites. The results of the model will allow the user to: Determine current geothermal plant disposal costs; Evaluate the cost-effectiveness of alternative treatment techniques; and Evaluate the economic effects of changes in disposal regulations.
Date: September 1, 1987
Creator: unknown
System: The UNT Digital Library
Sulfur tolerant anode materials (open access)

Sulfur tolerant anode materials

The goal of this program is the development of a molten carbonate fuel cell (MCFC) anode which is more tolerant of sulfur contaminants in the fuel than the current state-of-the-art nickel-based anode structures. This program addresses two different but related aspects of the sulfur contamination problem. The primary aspect is concerned with the development of a sulfur tolerant electrocatalyst for the fuel oxidation reaction. A secondary issue is the development of a sulfur tolerant water-gas-shift reaction catalyst and an investigation of potential steam reforming catalysts which also have some sulfur tolerant capabilities. These two aspects are being addressed as two separate tasks.
Date: February 1, 1987
Creator: unknown
System: The UNT Digital Library
Determination of optimum electrolyte composition for molten carbonate fuel cells (open access)

Determination of optimum electrolyte composition for molten carbonate fuel cells

The objective of this study is to determine the optimum electrolyte composition for molten carbonate fuel cells. To accomplish this, the contractor will provide: (1) Comprehensive reports of on-going efforts to optimize carbonate composition. (2) A list of characteristics affected by electrolyte composition variations (e.g. ionic conductivity, vapor pressure, melting range, gas solubility, exchange current densities on NiO, corrosion and cathode dissolution effects). (3) Assessment of the overall effects that these characteristics have on state-of-the-art cell voltage and lifetime.
Date: January 1, 1987
Creator: Yuh, C. Y. & Pigeaud, A.
System: The UNT Digital Library
Enhanced durability and reactivity for zinc ferrite desulfurization sorbent (open access)

Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.
Date: February 23, 1987
Creator: Jha, M. C. & Baltich, L. K.
System: The UNT Digital Library
Reduced waste generation technical work plan (open access)

Reduced waste generation technical work plan

The United States Department of Energy has established policies for avoiding plutonium losses to the waste streams and minimizing the generation of wastes produced at its nuclear facilities. This policy is evidenced in DOE Order 5820.2, which states Technical and administrative controls shall be directed towards reducing the gross volume of TRU waste generated and the amount of radioactivity in such waste.'' To comply with the DOE directive, the Defense Transuranic Waste Program (DTWP) supports and provides funding for specific research and development tasks at the various DOE sites to reduce the generation of waste. This document has been prepared to give an overview of current and past Reduced Waste Generation task activities which are to be based on technical and cost/benefit factors. The document is updated annually, or as needed, to reflect the status of program direction. Reduced Waste Generation (RWG) tasks encompass a wide range of goals which are basically oriented toward (1) avoiding the generation of waste, (2) changing processes or operations to reduce waste, (3) converting TRU waste into LLW by sorting or decontamination, and (4) reducing volumes through operations such as incineration or compaction.
Date: May 1, 1987
Creator: unknown
System: The UNT Digital Library
''Follow that quarkexclamation'' (and other exclusive stories) (open access)

''Follow that quarkexclamation'' (and other exclusive stories)

Quarks are considered to be the basic constituents of matter. In a series of recent experiments, Carroll studied exclusive reactions as a means of determining the interactions between quarks. Quantum Chromo-dynamics (QCD) is the modern theory of the interaction of quarks. This theory explains how quarks are held together via the strong interaction in particles known as hadrons. Hadrons consisting of three quarks are called baryons. Hadrons made up of a quark and an antiquark are called mesons. In his lecture, Carroll describes what happens when two hadrons collide and scatter to large angles. The violence of the collision causes the gluons that bind the quarks in a particular hadron to temporarily lose their grip on particular quarks. Quarks scramble toward renewed unity with other quarks, and they undergo rearrangement, which generally results in additional new particles. A two-body exclusive reaction has occurred when the same number of particles exist before and after the collisions. At large angles these exclusive reactions are very rare. The labels on the quarks known as flavor enable the experimenter to follow the history of individual quarks in detail during these exclusive reactions. Carroll describes the equipment used in the experiment to measure short distance, …
Date: June 17, 1987
Creator: Carroll, A. S.
System: The UNT Digital Library
Heavy ion fusion accelerator research (HIFAR) year-end report, April 1, 1987-September 30, 1987 (open access)

Heavy ion fusion accelerator research (HIFAR) year-end report, April 1, 1987-September 30, 1987

The basic objective of the Heavy Ion Fusion Accelerator Research (HIFAR) program is to access the suitabilty of heavy ion accelerators as iginiters for Inertial Confinement Fusion (ICF). A specific accerelator techonolgy, the induction linac, has been studied at the Lawerence Berkeley Laboratory and has reached the point at which its viability for ICF applications can be assessed over the next few years. The HIFAR program addresses the generation of high-power, high-brightness beams of heavy ions, the understanding of the scaling laws in this novel physics regime, and the vadidation of new accelerator strategies, to cut costs. The papers in this report that address these goals are: MBE-4 mechanical progress, alignment of MBE-4, a compact energy analyzer for MBE-4, Cs/sup +/ injector modeling with the EGUN code, an improved emittance scanning system for HIFAR, 2-MV injector, carbon arc source development, beam combining in ILSE, emittance growth due to transverse beam combining in ILSE - particle simulation results, achromatic beam combiner for ILSE, additional elements for beam merging, quadrupole magnet design for ILSE, and waveforms and longitudinal beam-parameters for ILSE.
Date: December 1, 1987
Creator: unknown
System: The UNT Digital Library