Significant progress has been made toward solving the century-old problem of chromatic aberrations in diffractive optics. Our approach exploits modern materials and microfabrication technology and is very different from the purely diffractive strategy,'' which is commonly employed and which results in multiple diffractive elements separated by a finite distance. We have developed a Fresnel zone plate lens comprised of a serial stack of patterned minus-filters which allows broadband radiation to be focused (or imaged) without longitudinal or transverse chromatic aberrations. 7 refs., 4 figs.

Air infiltration is an important factor in heat loss and indoor air quality; in modern well-insulated homes, it may account for as much as half of the total heat loss. Due to the recent emphasis by home buyers and manufacturers on energy efficiency, tighter homes are being constructed. In the past, it was assumed that natural infiltration would provide adequate ventilation to maintain acceptable indoor air quality, but this is no longer the case in modern energy-efficient homes. This report summarizes the results of infiltration measurements made on two groups of manufactured homes in the Bonneville Power Administration (BPA) service area: 131 energy-efficient homes constructed under RCDP, and a control group of 29 homes not participating in energy-efficiency programs.

This feasibility study examines reliability centered maintenance (RCM) as it applies to Bonneville Power Administrations (BPA) substation maintenance program. Reliability techniques are examined in evaluated. Existing BPA equipment maintenance procedures are documented. Equipment failure history is considered. Economic impacts are estimated. Various equipment instrumentation methods are reviewed. Based on this analysis a prototype system is proposed. The prototype will be implemented in two phases. Phase 1 is to be completed in 1992, it includes instrumenting one power transformer and one oil circuit breaker. Software development will focus on displaying data. Phase 2 is to be completed the following year. The remaining transformers and breakers will be instrumented during the second phase. Software development will focus on predictive maintenance techniques and maintenance decision support.

The objective is to develop and test various integrated solar heating, cooling and domestic hot water systems, and to evaluate their performance. Systems composed of new, as well as previously tested, components are carefully integrated so that effects of new components on system performance can be clearly delineated. The SEAL-DOE program includes six tasks which have received funding for the 1991--92 fifteen-month period. These include: (1) a project employing isothermal operation of air and liquid solar space heating systems; (2) a project to build and test several generic solar water heaters; (3) a project that will evaluate advanced solar domestic hot water components and concepts and integrate them into solar domestic hot water systems; (4) a liquid desiccant cooling system development project; (5) a project that will perform system modeling and analysis work on solid desiccant cooling systems research; and (6) a management task. The objectives and progress in each task are described in this report. 6 figs.

This report discusses the following topics on the effect radiation has on thermonuclear reactor materials: Atomic Displacements; Microstructure Evolution; Materials Engineering, Mechanics, and Design; Research on Low-Activation Steels; and Research Motivated by Grant Support.

The objective of proposed research is development of catalysts with enhanced slurry phase activity and better selectivity to fuel range products, through a more detailed understanding and systematic studies of the effects of pretreatment procedures and promoters/binders (silica) on catalyst performance.

In April 1987, Air Products started the third and final contract with the US Department of Energy to develop the Liquid Phase Methanol (LPMEOH) process. One of the objectives was to identify alternative commercial catalyst(s) for the process. This objective was strategically important as we want to demonstrate that the LPMEOH process is flexible and not catalyst selection limited. Among three commercially available catalysts evaluated in the lab, the catalyst with a designation of F21/0E75-43 was the most promising candidate. The initial judging criteria included not only the intrinsic catalyst activity but also the ability to be used effectively in a slurry reactor. The catalyst was then advanced for a 40-day life test in a laboratory 300 cc autoclave. The life test result also revealed superior stability when compared with that of a standard catalyst. Consequently, the new catalyst was recommended for demonstration in the Process Development Unit (PDU) at LaPorte, Texas. This report details the methodology of testing and selecting the catalyst.

The LPMEOH process was conceived and patented by Chem Systems Inc. in 1975. Initial research and studies on the process focused on two distinct modes of operation. The first was a liquid fluidized mode with relatively large catalyst pellets suspended in a fluidizing liquid, and the second was an entrained (slurry) mode with fine catalyst particles slurried in an inert liquid. The development of both operating modes progressed in parallel from bench scale reactors, through an intermediate scale lab PDU, and then to the LaPorte PDU in 1984. The slurry mode of operation was ultimately chosen as the operating mode of choice due to its superior performance.

On December 24, 1991, the K-Reactor was in the shutdown mode with full AC process water flow and full cooling water flow. Safety rod testing was being performed as part of the power ascension testing program. The results of cooling water samples indicated tritium concentrations higher than allowable. Further sampling and testing confirmed a Process Water System to Cooling Water System leak in heat exchanger 4A (HX 4A). The heat exchanger was isolated and the plant shutdown. Heat exchanger 4kA was removed from the plant and moved to C-Area prior to performing examinations and diagnostic testing. This included locating and identifying the leaking tube or tubes, eddy current examination of the leaking tube and a number of adjacent tubes, visually inspecting the leaking tube from both the inside as well as the area surrounding the failure mechanism. In addition ten other tubes that either exhibited eddy current indications or would represent a baseline condition were removed from heat exchanger 4A for metallurgical examination. Additional analysis and review of heat exchanger leakage history was performed to determine if there are any patterns which can be used for predictive purposes. Compensatory actions have been taken to improve the sensitivity and response time …

The objective for this experimental work was to examine the reaction mechanisms, half-collision dynamics, and other optically induced chemical effects, that are operable on a well characterized single-crystal semiconductor surface. Of particular interest were reactions induced by charge transfer from the semiconductor surface including hot carrier and thermalized carrier processes. The primary technique to measure the desorbed fragment translational energies was time-of-flight mass-spectroscopy, used in conjunction with a pulsed tunable laser source. The work was carried out in ultrahigh vacuum, thus other surface spectroscopies such as temperature-programmed desorption, (TPD), (LEED), etc. were used as needed. In the project, the photoreactions of several halogen-containing molecules on GaAs(110) surfaces have been investigated. The studies have made the first observations of several new photochemical processes on uhv prepared surfaces including intermolecular charge transfer; desorption by thermal-carrier-induced reactions (including the measurement of coverage-dependent changes in the translational energies of the desorbed products); interferometric oscillation of photoinduced reactions; and self-quenching of thermal carrier reactions on surfaces.

An imaging beamline based on a Kirkpatrick-Baez mirror configuration has been designed to image the electron beam in the ALS storage ring, to measure its size and shape. The electron beam emittance will be small ({epsilon}h = 3.4 {times} 10{sup {minus}9} m rad) and the quality of the image is extremely sensitive to surface figure distortion of the mirrors. Thermal distortions and surface temperatures have been calculated for radiatively cooled mirrors of various materials in a search for a simple design which avoids water cooling. The choice of mirror material and the thermal and mechanical design is discussed. 6 refs.

Correspondence issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed federal programs created to address the needs of at-risk and delinquent youths, focusing on: (1) identifying at-risk and delinquent youth programs that included mentoring as a type of service; (2) who administers the programs; (3) the objectives of the programs; and (4) the authorizing legislation for the programs."

Other written product issued by the General Accounting Office with an abstract that begins "Pursuant to a legislative requirement, GAO reviewed the Social Security Administration's (SSA) new rule on the effective date of application for Supplemental Security Income benefits. GAO noted that: (1) the rule implements section 204 of the Personal Responsibility and Work Opportunity Reconciliation Act of 1996, which changes the date a social security application is effective so that the earliest month for which benefits can be paid is the month following the month in which the application is filed; (2) previously, benefits were prorated for the month in which the application was filed; (3) the rule makes changes concerning emergency advance payments, interim assistance reimbursements, and in the definition of eligible spouse; and (4) SSA complied with applicable requirements in promulgating the rule."

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO determined whether the Federal Aviation Administration (FAA) must enforce grant assurance as a condition of providing noise mitigation grants to the Seattle-Tacoma International Airport."

Correspondence issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reported on the Department of the Treasury's decision to change the calculation of the interest rates used since 1980 to determine the investment returns for a number of government trust funds, including Social Security and Medicare, focusing on: (1) how and why Treasury changed its rules for calculating interest rates in 1980 and 1998; (2) the effects of these changes on the unified budget and on the financial status of Social Security and Medicare trust funds; and (3) what other trust funds were affected by Treasury's decision."

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on families no longer receiving welfare, focusing on: (1) the extent to which states have reported information on the condition of families who have left welfare in the following key areas: (a) economic status; (b) family composition; and (c) family and child well-being; (2) generalizable state studies on what is known about the status of former welfare families in the key areas; and (3) federal and state efforts to improve the usefulness of the data obtained through these state efforts."

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on the potential threat to the public's health from antimicrobial resistant bacteria, focusing on: (1) what is known about the public health burden--in terms of illnesses, deaths and treatment costs--due to antimicrobial resistance; (2) potential future burden, given what is known about the development of resistance in microbes and usage of antimicrobials; and (3) federal efforts to gather and provide information about resistance."

Correspondence issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO: (1) identified census tracts in medium-sized to large cities that met specific poverty criteria; and (2) provided additional information on each census tract."

Correspondence issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on year 2000 readiness of State Employment Security Agencies' (SESA) unemployment insurance benefits and tax systems and determined the reported status of whether these systems have been independently verified and validated for year 2000 compliance. GAO also determined whether SESAs have submitted contingency plans for continuity of business operations."

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO updated its previous report on United Nations (U.N.) financial issues and U.S. arrears, focusing on: (1) the amount the United States will need to pay before the end of 1999 to avoid losing its right to vote in the U.N. General Assembly; (2) the trend in U.S. assessed contributions and arrears that has led to the current situation; (3) U.S. arrears and the amounts withheld for legislative and policy reasons; and (4) the status of member states that lost their right to vote in the General Assembly at the beginning of 1999."

A letter report issued by the General Accounting Office with an abstract that begins "GAO reviewed certain discrepancies in the complaint data that the Postal Service reported to the Equal Employment Opportunity Commission (EEOC) and the need for the Service to take additional steps to ensure that such data are complete, accurate, and reliable."

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided information on the management of female inmate populations."

A chapter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO reviewed the status of the Department of Energy's (DOE) Accelerated Strategic Computing Initiative (ASCI), focusing on: (1) whether the program is meeting its key milestones and whether hardware and software developments are adequate to date; (2) whether the program is within its projected budget; and (3) what key technical risks the program faces."

A letter report issued by the General Accounting Office with an abstract that begins "Pursuant to a congressional request, GAO provided a status report on the construction of the new Washington Convention Center, focusing on: (1) the status of the project; (2) changes in the Washington Convention Center Authority's (WCCA) estimated project costs and financing plan since GAO's last report; and (3) actual expenditures and collection of dedicated taxes."