A formula is derived, which allows efficient analytical evaluation of the long range beam-beam tune shifts and chromaticities with amplitude. It assumes that the beams are infinitely short, oppositely charged, and with Gaussian transversal profile. The formula employs an infinite sum with favorable convergence rates, making it well suited especially for the long range case. Applications to the Tevatron are presented, including some proposed compensation schemes and their effect on the dynamic aperture.

The authors report a series of {micro}SR measurements performed on single crystals of La{sub 1-x}Sr{sub x}MnO{sub 3} (0 {le} x {le} 0.125) and on a polycrystalline bilayer manganite La{sub 2-2x}Sr{sub 1+2x}Mn{sub 2}O{sub 7} (x = 0.52). They find that the temperature dependence of the spin-lattice relaxation rate is strongly dependent on the hole doping and the associated changes in the magnetic structure. The systems have competing, anisotropic interactions, leading to a complex interplay of charge, spin and orbital order. This has a significant influence on the spin dynamics, both for perovskite and layered manganites.

The Chemical Technology Division (CMT) is one of eight engineering research divisions within Argonne National Laboratory, one of the U.S. government's oldest and largest research laboratories. The University of Chicago oversees the laboratory on behalf of the U.S. Department of Energy (DOE). Argonne's mission is to conduct basic scientific research, to operate national scientific facilities, to enhance the nation's energy resources, and to develop better ways to manage environmental problems. Argonne has the further responsibility of strengthening the nation's technology base by developing innovative technology and transferring it to industry. CMT is a diverse early-stage engineering organization, specializing in the treatment of spent nuclear fuel, development of advanced electrochemical power sources, and management of both high- and low-level nuclear wastes. Although this work is often indistinguishable from basic research, our efforts are directed toward the practical devices and processes that are covered by Argonne's mission. Additionally, the Division operates the Analytical Chemistry Laboratory and Environment, Safety, and Health Analytical Chemistry services, which provide a broad range of analytical services to Argonne and other organizations. The Division is multidisciplinary. Its people have formal training as ceramists; physicists; material scientists; electrical, mechanical, chemical, and nuclear engineers; and chemists. They have experience working …

This report includes recent developments in federal child care programs and tax provisions. The report discusses several federal programs that support child care or related services, primarily for low-income working families. In addition, the tax code includes provisions specifically targeted to assist families with child care expenses. The report presents the legislative activity in the 107th Congress in regard to child care legislature and provisions.

The change in focus of a high-resolution electron microscope is generally assumed to be linear with change in objective lens current. Thus the defocus step size should be constant for a constant step in lens current. Measurements on the LBNL One-Angstrom Microscope show that the step size increases with increasing underfocus (reduced lens current). Differentiation of the best-fit quadratic shows that the defocus step size varies linearly as defocus changes.

A ceramic waste form has been developed to immobilize the salt waste stream from electrometallurgical treatment of spent nuclear fuel. The ceramic waste form was originally prepared in a hot isostatic press (HIP). Small HIP capsules called witness tubes were used to obtain representative samples of material for process monitoring, waste form qualification, and archiving. Since installation of a full-scale HIP in existing facilities proved impractical, a new fabrication process was developed. This process fabricates waste forms inside a stainless steel container using a conventional furnace. Progress in developing a new method of obtaining representative samples is reported.

Alloy 22 (UNS N06022) is a candidate material for the external wall of the high level nuclear waste containers for the potential repository site at Yucca Mountain. In the mill-annealed (MA) condition, Alloy 22 is a single face centered cubic phase. When exposed to temperatures on the order of 600 C and above for times higher than 1 h, this alloy may develop secondary phases that are brittle and offer a lower corrosion resistance than the MA condition. The objective of this work was to age Alloy 22 at temperatures between 482 C and 800 C for times between 0.25 h and 3,000 h and to study the corrosion performance of the resulting material. Aging was carried out using wrought specimens as well as gas tungsten arc welded (GTAW) specimens. The corrosion performance was characterized using standard immersion tests in aggressive acidic solutions and electrochemical tests in multi-component solutions. Results show that, in general, in aggressive acidic solutions the corrosion rate increased as the aging temperature and aging time increased. However, in multi ionic environments that could be relevant to the potential Yucca Mountain site, the corrosion rate of aged material was the same as the corrosion rate of the …

The events of September 11, 2001, and the subsequent anthrax incidents have prompted some observers to suggest creating a capability for a virtual or electronic Congress (e-Congress) that could function in the event of an emergency. Currently, it is unclear exactly how an e-Congress would be constituted and operated; however, a proposal (H.R. 3481) has been introduced to require the National Institute of Standards and Technology (NIST) to investigate the feasibility and costs of implementing a computer system for remote voting and communication for Congress to ensure business continuity for congressional operations.

High-precision instrumentation, such as that for x-ray diffraction, electron microscopy, scanning probe microscopy, and other optical micropositioning systems, requires the stability that comes from vibration-isolated support structures. Structure-born vibrations impede the acquisition of accurate experimental data through such high-precision instruments. At the Advanced Photon Source, a multiaxis goniometer is installed in the 2-ID-D station for synchrotron microdiffraction investigations. However, ground vibration can excite the kinematic movements of the goniometer linkages, resulting in critically contaminated experimental data. In this paper, the vibration behavior of the goniometer has been considered. Experimental vibration measurements were conducted to define the present vibration levels and determine the threshold sensitivity of the equipment. In addition, experimental modal tests were conducted and used to guide an analytical finite element analysis. Both results were used for finding the best way to reduce the vibration levels and to develop a vibration damping/isolation structure for the 2-ID-D goniometer. The device that was designed and tested could be used to reduce local vibration levels for the vibration isolation of similar high-precision instruments.

Solid-particle erosion studies were conducted on a representative geopolymer. The test conditions were normal impact of 390-{micro}m angular Al{sub 2}O{sub 3} erodent particles moving at 50, 70, or 100 m/s. Steady-state erosion rates were obtained and the material-loss mechanism was studied by scanning electron microscopy. The geopolymer responded as a classic brittle material. Elastic-plastic indentation events led to formation of brittle cleavage cracks that resulted in spallation of material. The erosion rate was proportional to erodent velocity to the 2.3 power. The erosion rate and mechanism for the geopolymer were nearly identical to what has been observed for erosion of Si single crystals.

The manipulation of x-rays by phase structures is becoming more common through devices such as compound refractive lenses, blazed zone-plates and other structures. A spiral phase modulation structure can be used to condition an x-ray beam to produce an x-ray vortex. An x-ray beam in this form can be used as the first step towards a self-collimating beam. Also it can be used as a controllable pathological feature in studies of x-ray phase retrieval. The authors describe the microfabrication of a spiral phase modulation structure by excimer laser ablation. A multi-step fabrication using 15 separate chrome-on-quartz mask patterns is used to create a 16 step spiral staircase structure approximating the desired spiral ramp. The results of simulations and initial experimental results are presented.

This report discusses opportunities and challenges regarding Federal Chief Information Officer (CIO).

This final report describes results for investigation of aptameric stationary phases for separation of PAHs and metals.

This report provides background concerning various aspects of fuel ethanol, and a discussion of the current related policy issues.

This report provides background concerning various aspects of fuel ethanol, and a discussion of the current related policy issues

This report examines these issues by using two different modeling approaches to estimate the benefits potentially offered by the credits to young adults who are currently out-of-school, and the eligibility of currently enrolled aided students for the tax benefits and how much they might receive.

Testimony issued by the General Accounting Office with an abstract that begins "The challenges posed by homeland security exceed the capacity and authority of any one level of government. Protecting the nation against these threats calls for a truly integrated approach, bringing together the resources of all levels of government. The proposed Department of Homeland Security will have a central role in efforts to enhance homeland security. The proposed consolidation of homeland security programs has the potential to reduce fragmentation, improve coordination, and clarify roles and responsibilities. However, formation of a department should not be considered a replacement for the timely issuance of a national homeland security strategy to guide implementation of the complex mission of the department. Appropriate roles and responsibilities within and between the government and private sector need to be clarified. New threats are prompting a reassessment and shifting of long-standing roles and responsibilities, but these shifts are being considered on a piecemeal and ad hoc basis without benefit of an overarching framework and criteria. A national strategy could provide guidance by more systematically identifying the unique capacities and resources at each level of government to enhance homeland security and by providing increased accountability within the intergovernmental …

We report the synthesis of Sr{sub 1-x}Ca{sub x}MnO{sub 3} and La{sub 0.5}Ba{sub 0.5}MnO{sub 3} perovskites over extended cation and oxygen composition ranges and describe the dependence of their phase stability on the tolerance factor t = t(x,T,{delta}) that is a function of composition, temperature, and oxygen content. We show that magnetic transition temperatures depend strongly on the tolerance factor and charge disorder while dependence on the structural disorder is less important. By reducing charge and structural disorder we have significantly increased the Curie and Neel temperatures for perovskite manganites.

It is attempted in this paper to define an optimal range of subcriticality of ADS systems from the operational and safety points of view. To devise a representative measure of the subcriticality level, the mathematical and physical implications of the effective multiplication factor and the source multiplication factor have been reviewed. A set of criteria that bound the feasible subcriticality level is proposed in terms of the effective multiplication factor; the minimum required subcriticality is determined by the largest value of potential reactivity increase including the temperature defect and the calculation and measurement uncertainties, and the maximum allowable subcriticality level is bounded by the system economy and the technical feasibility of the system. Within this feasible domain of subcriticality, a preliminary estimation of the optimal range of subcriticality was performed for a lead-bismuth-eutectic (LBE) cooled ADS design based on the safety and transmutation performances. The effects on the system safety of the subcriticality level were analyzed for several important transients using an integral safety analysis method, and the transmutation performance was evaluated in terms of the fuel and long-lived fission product discharge burnups.

Measurements of the spectrum of Fe{sup 24+} in the 1.845 {angstrom} to 1.885 {angstrom} range obtained on the EBIT-I electron beam ion trap at Lawrence Livermore National Laboratory were used for determining the radiative lifetime of the ls2p {sup 1}P{sub 1} excited state. The spectrum contains electric dipole forbidden transitions at 1.855{angstrom} (''x'') and 1.868{angstrom} (''z'') whose lineshape is well represented by a Gaussian line profile and is assumed to be due primarily to Doppler and instrumental broadening. The Gaussian contribution is assumed to be the same for all lines in the spectrum. This assumption simplifies the problem when considering a more complex combination of broadening mechanisms. For allowed transitions such as 1s2p {sup 1}P{sub 1} {yields} 1s{sup 2} {sup 1}S{sub 0}, ''w'', at 1.850 {angstrom} we assume a Voigt profile. In the simplest case this combines both natural (Lorentzian) and Doppler (Gaussian) broadening effects which contribute to the width of the spectral line. With the Gaussian contribution determined from lines ''x'' and ''z'', deconvolving the Gaussian from the Voigt profile gives the natural line width. This then is directly related to the radiative lifetime of the 1s2p {sup 1}P{sub 1} excited level.

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Laser-based shock experiments have been conducted in thin Si and Cu crystals at pressures above the Hugoniot Elastic Limit (HEL). In these experiments, static film and x-ray streak cameras recorded x-rays diffracted from lattice planes both parallel and perpendicular to the shock direction. This data showed uniaxial compression of Si (100) along the shock direction and 3-D compression of Cu (100). In the case of the Si diffraction, there was a multiple wave structure observed, which may be due to a 1-D phase transition or a time variation in the shock pressure. A new film-based detector has been developed for these in-situ dynamic diffraction experiments. This large-angle detector consists of 3 film cassettes that are positioned to record x-rays diffracted from a shocked crystal anywhere within a full {pi}-steradian. It records x-rays that are diffracted from multiple lattice planes both parallel and at oblique angles with respect to the shock direction. It is a time-integrating measurement, but time-resolved data may be recorded using a short duration laser pulse to create the diffraction source x-rays. This new instrument has been fielded at the OMEGA and Janus lasers to study single crystal materials shock compressed by direct laser irradiation. In these experiments, …

A typical glass furnace consists of a combustion space and a melter. Intense heat is generated from the combustion of fuel and air/oxygen in the combustion space. This heat is transferred mainly by radiation to the melter in order to melt sand and cullet (scrap glass) eventually creating glass products. Many furnaces use electric boosters to enhance glass melting and increase productivity. The coupled electric/combustion heat transfer patterns are key to the glass making processes. The understanding of the processes can lead to the improvement of glass quality and furnace efficiency. The effects of electrical boosting on the flow patterns and heat transfer in a glass melter are investigated using a multiphase Computational Fluid Dynamics (CFD) code with addition of an electrical boosting model. The results indicate that the locations and spacing of the electrodes have large impacts on the velocity and temperature distributions in the glass melter. With the same total heat input, the batch shape (which is determined by the overall heat transfer and the batch melting rate) is kept almost the same. This indicates that electric boosting can be used to replace part of heat by combustion. Therefore, temperature is lower in the combustion space and the …

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