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The thermodynamic optimizations of the Nd-Sn and Sn-Tb binary systems were carried out by means of the Calculation of Phase Diagram (CALPHAD) method on the basis of the available experimental data including the thermodynamic properties and phase equilibria. The Gibbs free energies of the liquid, bcc, bct, dhcp and hcp phases were described by the substitutional solution model with the Redlich-Kister equation, while all of the intermetallic compounds (Nd5Sn3, Nd5Sn4, Nd11Sn10, NdSn, Nd3Sn5, NdSn2, Nd3Sn7, Nd2Sn5, NdSn3, Sn3Tb, βSn7Tb3, αSn7Tb3, Sn2Tb, Sn5Tb4, SnTb4, Sn10Tb11, Sn4Tb5 and Sn3Tb5) were described by the sublattice model. A set of self-consistent thermodynamic parameters of each phase in the Nd-Sn and Sn-Tb binary systems has been obtained, and the calculated results are in good agreement with the available experimental data.

Sintered metal fiber sheets (MFSs) made by sequential-overlap method are transversely isotropic open-cell cellular materials with paper-like fiber network architectures, which exhibit auxeticity and are promising for various potential applications due to the reentrant micro-structure. The thickness effect on the out-of-plane auxeticity (negative Poisson's ratio) of MFSs samples of 2–20 mm thick subjected to in-plane tensile loading is investigated with digital image correlation technique. Furthermore, the deformation modes of fibers within MFSs during various loading stages are examined with X-ray tomography. It is found that in addition to the straightening of reentrant fibers, fiber layers with defects and joints failure induced slippage between adjacent layers leads to local shear and results in unique umbrella-like local deformation termed umbrella effect, which gradually dominates the auxeticity during tensile loading. Although remarkably increasing lateral deformation, the umbrella effect significantly diminishes the in-plane mechanical performance such as rigidity and strength. In particular, this effect is suppressed by sample thickness: the overall performance tends to stabilize with sample thickness greater than a certain value, provided that the MFS is uniform with all fibers randomly distributed. The finding facilitates wider application of auxetic MFSs with further understanding on the relationship between the thickness effect and performance. Keywords: Metal fiber network, Auxetic behavior, Micro-structure, Size effect

Aiming at the problems of composites of anisotropic, poor in dimensional and uneven temperature field in the designing of composite tool in autoclave, the techniques of designing the composite tool of aircraft components were constructed, involving in the following aspects: Taking advantage of design flexibility of composites, the thermal expansion coefficient between the moulding board and composite components matched. By analyzing the cure process curve of fiber-reinforced composites, the result that the crisis point without stress between component and tool, which the shape of composite component decided was concluded. By the temperature field analysis, and contrasted with the experimental results, the maximum difference was 4.95°C，after analysis, optimized the structure of the tool, obtaining the relatively uniform temperature field of the board.

Failed oil tubes and the associated corrosion products from gas wells in the Zhongyuan oil field in China were studied by X-ray diffraction, X-ray photoelectron spectroscopy, and electron probe microanalysis. Results showed that CO2 and condensate were primary factors in the corrosion of the tubes. However, non-metallic inclusions in the steel played an important role in accelerating both localised corrosion and cracking in the CO2 containing environment. The possibility of using inhibitors in the gas wells to prevent this sweet gas corrosion was also investigated by means of corrosion tests in the laboratory.

The CALOR89 code system, already in wide use, is further validated against the recently available data for a test module of the calorimeter of the D0 detector, made of uranium absorbers and liquid argon. The experimental data considered include energy containment as a function of depth, the electron and pion resolutions, and the compensation ratios at 25 and 100 GeV/ c . The code system is then used to predict the performance of a Pb-LAr test module under construction and to test the expected performance improvement of a second Pb-LAr module with steel-cladded Pb absorbers. It is found that with a fixed total absorber thickness of 12 mm and LAr thickness of 4 mm, varying the thickness of the steel cladding has minor effects on the compensation ratios. However, for 20 GeV/ c incident electrons and 0.5-mm steel cladding, there is a significant improvement in energy resolution.

The concept of diffusion topography engineering (DTE) is proposed and exercised on state-of-the-art 65 nm technology for the first time. Diffusion region extended over STI and therefore resulting in T-shape diffusion profile is created purposely to suppress STI stress and oxide divot. This novel technique delivers up to 33% PMOS and 22% NMOS enhancement, respectively, and results in -10% R.O. speed improvement. When combined with high-stress contact-etch-stop-layer (CESL) , a significant 27% CMOS enhancement is achieved through preferable strain superposition. Both device integrity and reliability are carefully evaluated and neither of them is adversely impacted by DTE.

We report an optimized process-induced strained silicon (PSS) technology for 90nm CMOS generation and beyond. Through the superposition of various PSS techniques, up to 20% performance enhancement is achieved for both N- and PMOS at channel length down to 45nm. The PSS technology exhibits excellent gate oxide breakdown characteristics, isolation characteristics and reliability. A novel spacer-PSS technology is also proposed for the first time and /spl sim/7% enhancement in ring oscillator speed is observed.

This paper presents a state-of-the-art 65nm CMOS transistor technology using 300mm bulk substrate. Device offering is classified as High Speed (HS), General Purpose (G) and Low Power (LP) so as to cover the whole foundry application space with various power and performance requirement. High volume manufacturable 55nm / 45nm and

A leading edge 90nm bulk CMOS device technology is described in this paper. In this technology, multi Vt and multi gate oxide devices are offered to support low standby power (LP), general-purpose (G or ASIC), and high-speed (HS) system on chip (SoC) applications. High voltage I/O devices are supported using 70/spl Aring/, 50/spl Aring/, and 28/spl Aring/ gate oxide for 3.3V, 2.5V, and 1.5-1.8V interfaces, respectively. The backend architecture is based on nine levels of Cu interconnect with hot black diamond (HBD) low-k dielectric (k

An all-dry, double-level-metal technology for personalization of VLSI gate arrays is described. The goal is to provide rapid prototyping of new electronic systems, and to serve as the nucleus for a potential job-shop, low-volume manufacturing environment. The process development is examined for the demonstration of double-level-metal interconnect, with emphasis on novel technologies such as the laser direct write and single-wafer metal etching using the magnetron-enhanced reactive-ion-etching technique. A double-level-metal interconnect based on 100000 laser patterned 2- mu m vias has been successfully demonstrated using this technology. >

This report discusses the following topics on the Soleoidal Detector Collaboration: Summary and overview of the detector; physics and detector requirements; central tracking system; superconducting magnet; calorimetry; muon system; electronics; online computing; offline computing; safety; experimental facilities; installation; test and calibration beam plan; and cost and schedule summary.

The considerations that governed the development of the uncertainty files for the isotopes of Cr, Fe, Ni, Cu, and Pb in ENDF/B-VI are summarized. Four different approaches were used in providing the covariance information. Some examples are given which show the standard deviations as a function of incident energy and the corresponding correlation matrices. 11 refs., 5 tabs.

During the past several months, Tennessee, Mississippi, and the Oak Ridge National Laboratory have been coordinating efforts to benchmark the CALOR89 code system against the DO and HELIOS prototype calorimeter data, and to use the CALOR89 system to generate currently needed data for radiation damage studies, signal collection time, and compensation characteristics of various calorimeter designs. This report describes these results and gives our plans and projected budgets for the following year. 8 refs., 5 figs.

The traveler organized and chaired the meeting of the NEANDC/NEACRP Nuclear Data Evaluation Cooperation Subgroup-I: Intercomparison of USA, European, and Japanese Evaluations for {sup 52}Cr, {sup 56}Fe, and {sup 58}Ni, held on December 3, 1990, at the NEA Data Bank in Saclay, France. The traveler held discussions with Subgroup-II members to keep track of the activities of this group in which the traveler is a member. Highlights and/or recommendations of these meetings, as well as observations of the EAF, EFF, and JEF meetings, are included in this report.

Nuclear model codes were used to calculate cross sections for neutron-induced reactions on {sup 19}F for incident energies from 2 to 20 MeV. The model parameters in the codes were adjusted to best reproduce experimental data and are given in this report. The calculated results are compared to measured data and the evaluated values of ENDF/B-V. The covariance matrix for several of the most sensitive model parameters is given based on the scatter of measured data around the theoretical curves and the long-range correlation error of measured data. The results of these calculations form the basis for the new ENDF/B-VI fluorine evaluation. 44 refs., 64 figs., 14 tabs.

A survey was made of the available information on neutron and gamma-ray-production cross-section measurements of lead. From these and from relevant nuclear-structure information on the Pb isotopes, we prepared recommended neutron cross-section data sets for lead covering the neutron energy range from 0.00001 eV to 20.0 MeV. The cross sections are derived from experimental results available to February 1972 and from calculations based on optical-model, DWBA, and Hauser-Feshbach theories. Comparisons which show good agreement between theoretical and experimental values are displayed in a number of graphs. Also presented graphically are smoothed total cross sections, Legendre coefficients for angular distributions, and a representative energy distribution of gamma rays from resonance capture.

Cross sections for neutron interaction with Cu and Nb, with emphasis on spectra of light particles from binary reactions, are calculated for neutron energies from 4 to 32 MeV for estimating recoil probability densities for the analysis of damage experiments with a Be (d, n) neutron source. Nuclear model parameters were adjusted to reproduce the available cross-section data around 14 MeV. Helium production cross sections were also calculated for 63 Cu for neutrons below 20 MeV, as an illustration of the Hauser-Feshbach method for calculating tertiary reaction cross sections.

Primary recoil distributions and specific damage energies have been computed for high energy deuteron-breakup neutrons in Cu, Nb and Au. The calculations are based on theoretical neutron cross sections and consider in particular a d-Be spectrum broadly peaked at 15 MeV with some neutrons above 30 MeV. The theoretical results are similar to corresponding calculations for monoenergetic 15-MeV neutrons and are in good agreement with range measurements of (n, 2n) recoils generated by high energy d-Be neutrons in Nb and Au. The calculations are also consistent with recent d-Be neutron sputtering experiments in Nb and Au and demonstrate the usefulness of deuteron-breakup neutron sources for simulating fusion neutron effects.

Nuclear model codes were used to compute cross sections for neutron-induced reactions on /sup 63,65/Cu, /sup 58,60/Ni, and /sup 52/Cr for incident energies from 1 to 20 MeV. The input parameters for the model codes determined through analysis of experimental data in this energy region. The models used, the input data, the resulting calculations, and comparisons with measured data are discussed. 15 refs.

Cross-section and polarization data for neutron interaction with carbon below the inelastic threshold (4.81 MeV) were evaluated and analyzed by R -matrix theory. Six sets of total crosssection data below 2 MeV were partially smoothed and least-square fitted with non-diagonal weighting to obtain averages with estimated uncertainties for use in the R -matrix search program. The resulting differential scattering cross sections below 2 MeV are recommended as standards. The good quality of the fits well above 2 MeV and a high-precision (0.1%) thermal value enhance the confidence in the recommended values below 2 MeV.

Gamma-ray yields as a function of neutron energy for tantalum and tungsten have been generated with a combined experimental and theoretical approach. The results are presented in a format that woul...

Gamma-ray transition probabilities intended for use in the preparation of gamma-ray production cross sections have been calculated for four odd-A nuclei and compared with experiment. Wave functions...

Nuclear model codes were used to compute cross sections for neutron-induced reactions on both /sup 58/Ni and /sup 60/Ni for incident energies from 1 to 20 MeV. The input parameters for the model codes were determined through analysis of experimental data in this energy region. Discussion of the models used, the input data, the resulting calculations, extensive comparisons to measured data, and comparisons to the Evaluated Nuclear Data File (ENDF/B-V) for Ni (MAT 1328) are included in this report. 118 refs., 101 figs., 19 tabs.

Nuclear model codes were used to compute cross sections for neutron-induced reactions on /sup 40/Ca for incident energies from 20 to 40 MeV. The input parameters for the model codes were determined through analysis of experimental data in this energy region. Computed cross sections along with emission spectra for each product were combined into an Evaluated Nuclear Data File (ENDF) using the proposed format for charged-particle reactions. Discussion of the models used, the resulting calculations, and the final evaluated data file are presented.

An update of the ENDF/B-V Mod-3 evaluation for natural iron is described. The cross sections of (n,n') and (n,2n) reactions are revised. Energy-angle correlations in the secondary (n,n') neutrons are introduced in the ENDF/B-V formats. Anisotropic angular distributions are provided for the secondary neutrons in (n,2n), (n,np), and (n,n..cap alpha..) reactions. Revelant integral results, microscopic data, and nuclear model calculations that influence the revised results are summarized. 54 refs., 9 figs., 2 tabs.

A novel low cost borophosphosilicate glass (BPSG) technology suitable for one micron processing is presented here. This technique allows glass to be flowed consistently and reproducibly at temperatures as low as 750°C. Flow angles are independent of device linewidths from 1 to 10 microns. The flow angle can be adjusted by changing the deposition time. The simplicity of the process will probably enhance the reliability of the technique. Related issues such as photoresist adhesion and plasma etching have been examined. Application of this material as an interlayer dielectric in MOS circuits looks promising.

The evaluation of neutron and gamma-ray-production cross sections for natural iron is considered. Improvements for ENDF/B-V MAT 1326 are described and graphically compared with the previous version. A summary of the previous version and a general description of the current status of the evaluation are also given. 25 figures.