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Critical dimension sensitivity to post-exposure bake temperaturevariation in EUV photoresists

Description: Chemically amplified resists depend upon the post-exposure bake (PEB) process to drive the deprotection reactions (in positive resists) that lead to proper resist development. For this reason they often exhibit critical dimension (CD) sensitivity to PEB temperature variation. In this work the effects of variation in different aspects of the PEB step on post-develop CD are studied for two extreme ultraviolet (EUV) photoresists. The spatial and temporal temperature uniformity of the PEB plate is measured using a wireless sensor wafer. Programmed variations in the bake plate temperature set point are then used to measure the CD sensitivity to steady state temperature variation. In addition, the initial temperature ramp time is modified using a thin sheet of polyimide film between the wafer and the bake plate. This allows for measurement of the CD sensitivity to transient temperature variation. Finally, the bake time is adjusted to measure the CD sensitivity to this parameter.
Date: January 11, 2005
Creator: Cain, Jason P.; Naulleau, Patrick & Spanos, Costas J.
Partner: UNT Libraries Government Documents Department

A study of temperature transients at the inlet of a turbojet engine

Description: Report presenting wind-tunnel experiments on the effect of rapid temperature increases at the inlet of an engine in order to learn why inlet temperature transients disturb the operation of turbojet engines. The study was made over a range of altitudes, temperature-rise rates, and engine speeds. Results regarding pressure-ratio histories, required temperature rise for stall, effect of partial admission of hot gases to the compressor inlet, effect of altitude on stall and blowout, and effect of remedial measures are provided.
Date: June 26, 1957
Creator: Wallner, Lewis E.; Useller, James W. & Saari, Martin J.
Partner: UNT Libraries Government Documents Department


Description: Included in the conference proceedings are 69 papers grouped into the categories on the experimental and theoretical aspects of the scattering law,'' of spectra ln lattices and infinite media, and of transient and asymptotic phenomena. One paper in each of the categories is a summary of the material presented by the other papers in that group. Separate abstracts have been prepared for 52 papers, and 15 papers have been previously abstracted in NSA. (M.P.G.)
Date: October 31, 1963
Partner: UNT Libraries Government Documents Department


Description: We determine the impedance of a cylindrical metal tube (resistor) of radius a, length g, and conductivity {sigma}, attached at each end to perfect conductors of semi-infinite length. Our main interest is in the asymptotic behavior of the impedance at high frequency, k >> 1/a. In the equilibrium regime, , the impedance per unit length is accurately described by the well-known result for an infinite length tube with conductivity {sigma}. In the transient regime, ka{sup 2} >> g, we derive analytic expressions for the impedance and wakefield.
Date: May 15, 2005
Partner: UNT Libraries Government Documents Department

Numerical studies of enthalpy and CO2 transients in two-phasewells

Description: Numerical studies of enthalpy and CO2 transients for wellscompleted in composite reservoir systems are carried out. Both constantrate and constant pressure production are considered. The results showthat relatively small variations in hydrologic parameters and vaporsaturation can have large effects on the enthalpy and CO2 content of theproduced fluids. Field data are presented that illustrate the theoreticalresults obtained.
Date: April 1, 1984
Creator: Bodvarsson, Gudmundur S.
Partner: UNT Libraries Government Documents Department

Measured strain in Nb3Sn coils during excitation and quence

Description: The strain in a high field Nb{sub 3}Sn coil was measured during magnet assembly, cool-down, excitation and spot heater quenches. Strain was measured with a full bridge strain gauge mounted directly over the turns and impregnated with the coil. Two such coils were placed in a 'common coil' fashion capable of reaching 11 T at 4.2 K. The measured steady state strain in the coil is compared with results obtained using the FEM code ANSYS. During quenches, the transient strain (due to temperature rise) was also measured and compared with the calculated mechanical time response to a quench.
Date: June 1, 2005
Creator: Caspi, S.; Barlett, S.E.; Dietderich, D. R.; Ferracin, P.; Gourlay, S. A.; Hannaford, C. R. et al.
Partner: UNT Libraries Government Documents Department

Analyses of coupled hydrological-mechanical effects during drilling of the FEBEX tunnel at Grimsel

Description: This paper presents analyses of coupled hydrological-mechanical (HM) processes during drilling of the FEBEX tunnel, located in fractured granite at Grimsel, Switzerland. Two and three-dimensional transient finite-element simulations were performed to investigate HM-induced fluid-pressure pulses, observed in the vicinity of the FEBEX tunnel during its excavation in 1995. The results show that fluid-pressure responses observed in the rock mass during TBM drilling of the FEBEX tunnel could not be captured using current estimates of regional stress. It was also shown that the measured pressure responses can be captured in both two and three-dimensional simulations if the stress field is rotated such that contraction (compressive strain rate) and corresponding increases in mean stress occur on the side of the drift, where increased fluid pressure spikes were observed.
Date: September 2, 2003
Creator: Rutqvist, J.; Rejeb, A.; Tijani, M. & Tsang, C.-F.
Partner: UNT Libraries Government Documents Department

High altitude atmospheric discharges according to the runaway air breakdown mechanism

Description: High altitude optical transients - red sprites, blue jets, and elves - are modeled in the context of the relativistic electron runaway air breakdown mechanism. These emissions are usually associated with large mesoscale convective systems (hereafter MCS). In thunderstorms cloud electrification proceeds over a time scale long enough to permit the conducting atmosphere above the cloud to polarize and short out the thunderstorm electric field. When a lightning strike rapidly neutralizes a cloud charge layer runaway driving fields can develop in the stratosphere and mesosphere. According to present simulations of the full runaway process the variety of observed optical emissions are due to the nature of the normal lightning event in the MCS that kick starts the runaway avalanche. In this paper the authors describe some details of the model, present the results of the evolution of the primary electron population, and summarize the initial conditions necessary for different types of discharges. Two companion papers present (a) the predicted optical, gamma ray, and radio emissions caused by these electrical discharges, and (b) the time evolution of the secondary electron population and its implications in terms of observables.
Date: April 1, 1997
Creator: Symbalisty, E.; Roussel-Dupre, R.; Yukhimuk, V. & Taranenko, Y.
Partner: UNT Libraries Government Documents Department

Transient Inverse Calibration of Site-Wide Groundwater Model to Hanford Operational Impacts from 1943 to 1996--Alternative Conceptual Model Considering Interaction with Uppermost Basalt Confined Aquifer

Description: The baseline three-dimensional transient inverse model for the estimation of site-wide scale flow parameters, including their uncertainties, using data on the transient behavior of the unconfined aquifer system over the entire historical period of Hanford operations, has been modified to account for the effects of basalt intercommunication between the Hanford unconfined aquifer and the underlying upper basalt confined aquifer. Both the baseline and alternative conceptual models (ACM-1) considered only the groundwater flow component and corresponding observational data in the 3-Dl transient inverse calibration efforts. Subsequent efforts will examine both groundwater flow and transport. Comparisons of goodness of fit measures and parameter estimation results for the ACM-1 transient inverse calibrated model with those from previous site-wide groundwater modeling efforts illustrate that the new 3-D transient inverse model approach will strengthen the technical defensibility of the final model(s) and provide the ability to incorporate uncertainty in predictions related to both conceptual model and parameter uncertainty.
Date: August 29, 2001
Creator: Vermeul, Vince R; Cole, Charles R; Bergeron, Marcel P; Thorne, Paul D & Wurstner, Signe K
Partner: UNT Libraries Government Documents Department

Transient Inverse Calibration of Hanford Site-Wide Groundwater Model to Hanford Operational Impacts - 1943 to 1996

Description: This report describes a new initiative to strengthen the technical defensibility of predictions made with the Hanford site-wide groundwater flow and transport model. The focus is on characterizing major uncertainties in the current model. PNNL will develop and implement a calibration approach and methodology that can be used to evaluate alternative conceptual models of the Hanford aquifer system. The calibration process will involve a three-dimensional transient inverse calibration of each numerical model to historical observations of hydraulic and water quality impacts to the unconfined aquifer system from Hanford operations since the mid-1940s.
Date: May 2001
Creator: Cole, Charles R.; Bergeron, Marcel P.; Wurstner, Signe K.; Thorne, Paul D.; Orr, Samuel & Mckinley, Mathew I.
Partner: UNT Libraries Government Documents Department

Hydrogen Transport in Copper

Description: Hydrogen interaction with oxygen in copper exerts a significant influence on the apparent hydrogen diffusivity and the quantity of hydrogen absorbed. Correlation of the amount of absorbed tritium with oxygen content and dependence of permeation transients on both oxygen content and prior treatment indicate that both reversible and irreversible interactions occur between hydrogen and dissolved oxygen. This paper discusses results of that study.
Date: October 23, 2001
Creator: Caskey, G. R., Jr.
Partner: UNT Libraries Government Documents Department

Gas Releases During Saltcake Dissolution for Retrieval of Single-Shell Tank Waste

Description: It is possible to retrieve a large fraction of soluble waste from the Hanford single-shell waste tanks (SST) by dissolving it with water. This retrieval method will be demonstrated in U-107 and S-112 in the next few years. If saltcake dissolution proves practical and effective, many of the saltcake SSTs may be retrieved by this method. Many of the SSTs retain a large volume of flammable gas that will be released into the tank headspace as the waste dissolves. This report describes the physical processes that control dissolution and gas release. Calculation results are shown describing the headspace hydrogen concentration transient during dissolution. The observed spontaneous and induced gas releases from SSTs is summarized and the dissolution of the crust layer in SY-101 is discussed as a recent example of full-scale dissolution of saltcake containing a very large volume of retained gas. The report concludes that the dissolution rate is self limiting and gas release rates are relatively low.
Date: July 31, 2001
Creator: Stewart, Charles W
Partner: UNT Libraries Government Documents Department

Development of Novel, Simple Multianalyte Sensors for Remote Environmental Analysis

Description: Advancement of our polymerized crystalline colloidal array chemical sensing technology. They have dramatically advanced their polymerized crystalline colloidal array chemical sensing technology. They fabricated nonselective sensors for determining pH and ionic strength. They also developed selective sensors for glucose and organophosphorus mimics of nerve gas agents. They developed a trace sensor for cations in water which utilized a novel crosslinking sensing motif. In all of these cases they have been able to theoretically model their sensor response by extending hydrogel volume phase transition theory. They also developed transient sampling methods to allow their ion sensing methods to operate at high ionic strengths. They also developed a novel optrode to provide for simple sampling.
Date: February 18, 2003
Creator: Asher, Sanford A.
Partner: UNT Libraries Government Documents Department

Temperature and spectral investigation of bulk KDP below damage using 355 nm laser irradiation

Description: A spectral and temperature investigation of fast-grown KDP crystals under high fluence, 355 nm laser irradiation is discussed. Pump-and-probe Raman spectroscopy indicate transient changes of the vibrational spectrum. Photothermal deflection experiments provide information on the temporal behavior of the temperature change. The presence of emission in the visible and NIR spectral regions is attributed to the presence of impurities and/or defects in the crystal.
Date: October 1, 1997
Creator: Demos, S. G., LLNL
Partner: UNT Libraries Government Documents Department


Description: Initiation of reactions by intermittent irradiation is frequently encountered in physical, chemical, and biological systems. Mathematicai expressions for transient and steady state concentrations of reactive species in these systems are useful for predicting performance and for research purposes. A general method of formulation of the intermittent irradiation problem is presented herein, and illustrative solutions are obtained for radioactive decay chains and for the rotating sector method. 20 references. (auth)
Date: October 1, 1962
Creator: Hill, F.B.
Partner: UNT Libraries Government Documents Department

Towards a Scalable Fully-Implicit Fully-coupled Resistive MHD Formulation with Stabilized FE Methods

Description: This paper presents an initial study that is intended to explore the development of a scalable fully-implicit stabilized unstructured finite element (FE) capability for low-Mach-number resistive MHD. The discussion considers the development of the stabilized FE formulation and the underlying fully-coupled preconditioned Newton-Krylov nonlinear iterative solver. To enable robust, scalable and efficient solution of the large-scale sparse linear systems generated by the Newton linearization, fully-coupled algebraic multilevel preconditioners are employed. Verification results demonstrate the expected order-of-acuracy for the stabilized FE discretization of a 2D vector potential form for the steady and transient solution of the resistive MHD system. In addition, this study puts forth a set of challenging prototype problems that include the solution of an MHD Faraday conduction pump, a hydromagnetic Rayleigh-Bernard linear stability calculation, and a magnetic island coalescence problem. Initial results that explore the scaling of the solution methods are presented on up to 4096 processors for problems with up to 64M unknowns on a CrayXT3/4. Additionally, a large-scale proof-of-capability calculation for 1 billion unknowns for the MHD Faraday pump problem on 24,000 cores is presented.
Date: June 3, 2009
Creator: Shadid, J N; Pawlowski, R P; Banks, J W; Chacon, L; Lin, P T & Tuminaro, R S
Partner: UNT Libraries Government Documents Department