Other written product issued by the General Accounting Office with an abstract that begins "This journal of the International Organization of Supreme Audit Institutions (INTOSAI) includes articles regarding: (1) issues concerning auditing in the new century as discussed at the 17th Commonwealth Auditors-General Conference held in Sun City, South Africa in October 1999; (2) efforts to encourage public health services, public works, and technical assistance at the Organization of African Supreme Audit Institutions' 8th General Assembly held in Burkina Faso in October 1999; (3) discussions held by the Organization of Latin American and Caribbean Supreme Audit Institutions' 9th General Assembly in Paraguay; (4) an audit profile on Sierra Leone; and (5) activities within INTOSAI."

Other written product issued by the General Accounting Office with an abstract that begins "This journal of the International Organization of Supreme Audit Institutions (INTOSAI) includes articles regarding: (1) issues concerning auditing in the new century as discussed at the 17th Commonwealth Auditors-General Conference held in Sun City, South Africa in October 1999; (2) efforts to encourage public health services, public works, and technical assistance at the Organization of African Supreme Audit Institutions' 8th General Assembly held in Burkina Faso in October 1999; (3) discussions held by the Organization of Latin America and Caribbean Supreme Audit Institutions' 9th General Assembly in Paraguay; (4) an audit profile on Sierra Leone; and (5) activities within INTOSAI."

Other written product issued by the General Accounting Office with an abstract that begins "GAO provided information on the Joint Financial Management Improvement Program's current financial management initiatives, activities, and practices."

A procedure was developed to assign energy ratings to a photovoltaic (PV) module for five reference days that represent different climates.

The structure and effects of extended defects in rapid deposited polycrystalline Si thin films were studied using a combination of high-resolution transmission electron microscopy and first-principles total energy calculations.

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Nitrogen alloyed III-V semiconductor compounds have been intensely studied in recent years due to unusual effects caused by nitrogen alloying. These effects are exploited in band gap engineering for specific applications such as solar cells and blue lasers.

The excellent high temperature strength and thermal conductivity of molybdenum-base alloys provide attractive features for components in advanced magnetic and inertial fusion devices. Refractory metal alloys react readily with oxygen and other gases. Oxidized molybdenum in turn is susceptible to losses from volatile molybdenum trioxide species, (MoO3)m, in air and the hydroxide, MoO2(OH)2, formed from water vapor. Transport of radioactivity by the volatilization, migration, and re-deposition of these volatile species during a potential accident involving a loss of vacuum or inert environment represents a safety issue. In this report we present experimental results on the oxidation, volatilization and re-deposition of molybdenum from TZM in flowing air between 400 and 800°C. These results are compared with calculations obtained from a vaporization mass transfer model using chemical thermodynamic data for vapor pressures of MoO3(g) over pure solid MoO3 and an expression for the vapor pressures of MoO2(OH)2 from the literature. Calculations correlate well with experimental data.

The heterogeneity of hydrogen and deuterium on the nanometer scale has been probed by samll-angle neutron scattering (SANS) from a-Si:H and a-Si:D films. Films were depsoited by two techniques, plasma-enhanced chemical vapor deposition (PECVD) and hot-wire chemical vapor deposition (HWCVD) using conditions that yield high quality films and devices.

Magnetic susceptibility was suggested theoretically to be sensitive to the overall structural order of a-Si:H and is measured precisely for various a-Si:H thin films using a new technique.

The procedures for evaluating the performance of multijunctiion-concentrator cells at the National Renewable Energy Laboratory are described. The accurate measurement of the performance of multijunction cells requires accurate relative-quantum-efficiency-measurements, "matched" reference cells, and a spectrally adjustable solar simulator.

In this paper, we examine the areas in c-Si growth, materials, and processing that require improvement through research to overcome barriers to the implementation of the PV Roadmap's Si goals.

The atomic composition of the back surface of the CdTe layer in a CdTe/CdS photovoltiac (PV) device has a significant influence on the quality of the electrical contact to this layer. This paper reports the results of a systematic study that correlates the composition of the back surface with pre-contact processing and device performance.

We describe a technique of photoluminescence measurements with a resolutiion of microns. This technique is applied to examine the CdS/CdTe interface of CdTe solar cells.

This paper briefs the photothermal reliability studies we conducted on different encapsulation materials for some U.S. PV companies that are subcontractors of the Photovoltaic Manufacturing Technology (PVMaT) program.

Standard test procedures are being developed to assess the performance of stand-alone photovoltaic (PV) systems. This paper will present an overview of the latest procedure.

The objective of this work is to develop and optimize the new dye-sensitized solar cell technology. In view of the infancy of rutile material development for solar cells, the PV response of the dye-sensitized rutile-based solar cell is remarkably close to that of the anatase-based cell.

International market opportunities for the sale and deployment of photovoltaic (PV) systems abound and will continue to out-pace domestic, grid-connected opportunities for the foreseeable future.

An analytical model describing electron transport in dye-sensitized nanocrystalline TiO(2) solar cells is shown to account for the non-linear dependence of the electron transport rate on the electron concentration. Equations relating the influenece of an exponential distribtuion of surface states to electron transport are derived and verified by intensity-modulated photocurrent spectroscopy measurements. A slope of 69 meV is inferred for the surface-state distribution curve.

Historically, flat-plate photovoltaic (PV) modules have been rated at "peak-output" for power generated under Standard; Reporting Conditions (SRC) of 1000 Watts per square meter W/m2 global irradiance at a standard temperature (25degC) and reference spectral distribution. We examine the direct-normal irradiance, spectral distribution, ambient temperature, and wind speed to be used for evaluating flatplate and concentrator module performance. Our study is based upon the 30-year U.S. National Solar Radiation Data Base for conditions observed when the global irradiance on a 2-axis-tracked surface is 1000 W/m2. Results show commonly-used values for concentrator testing of 850 W/m2 for direct-normal irradiance and 20degC for ambient temperature are appropriate. Wind speed should be increased from 1 m/s to a more frequently observed 4 m/s. Differences between the reference direct-normal spectrum and spectra measured at three sites when broadband direct-normal irradiance and global-normal irradiance are near SRC irradiances suggest revisions to the reference spectra may be needed.

Based on recent cell improvements for space applications, multijunction cells apear to be ideal candidates for high efficiency, cost effective, PV concentrator systems.

Carbon dioxide sequestration by an ex-situ, direct aqueous mineral carbonation process has been investigated over the past two years. This process was conceived to minimize the steps in the conversion of gaseous CO2 to a stable solid. This meant combining two separate reactions, mineral dissolution and carbonate precipitation, into a single unit operation. It was recognized that the conditions favorable for one of these reactions could be detrimental to the other. However, the benefits for a combined aqueous process, in process efficiency and ultimately economics, justified the investigation. The process utilizes a slurry of water, dissolved CO2, and a magnesium silicate mineral, such as olivine [forsterite end member (Mg2SiO4)], or serpentine [Mg3Si2O5(OH)4]. These minerals were selected as the reactants of choice for two reasons: (1) significant abundance in nature; and (2) high molar ratio of the alkaline earth oxides (CaO, MgO) within the minerals. Because it is the alkaline earth oxide that combines with CO2 to form the solid carbonate, those minerals with the highest ratio of these oxides are most favored. Optimum results have been achieved using heat pretreated serpentine feed material, sodium bicarbonate and sodium chloride additions to the solution, and high partial pressure of CO2 (PCO2). Specific …