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On Carrier Facilitated Transport Through Membranes

Description: Facilitated transport is a process, whereby the diffusion of a solute across a membrane is chemically enhanced. In this report an analysis is given of a facilitated transport system involving a volatile species A which reacts with a nonvolatile carrier species B to form the nonvolatile product AB.
Date: June 1980
Creator: Kaper, H. G.; Leaf, G. K. & Matkowsky, Bernard J.
Partner: UNT Libraries Government Documents Department

Users Manual for TART 2002: A Coupled Neutron-Photon 3-D, Combinatorial Geometry Time Dependent Monte Carlo Transport Code

Description: TART 2002 is a coupled neutron-photon, 3 Dimensional, combinatorial geometry, time dependent Monte Carlo radiation transport code. This code can run on any modern computer. It is a complete system to assist you with input preparation, running Monte Carlo calculations, and analysis of output results. TART 2002 is also incredibly FAST; if you have used similar codes, you will be amazed at how fast this code is compared to other similar codes. Use of the entire system can save you a great deal of time and energy. TART 2002 is distributed on CD. This CD contains on-line documentation for all codes included in the system, the codes configured to run on a variety of computers, and many example problems that you can use to familiarize yourself with the system. TART 2002 completely supersedes all older versions of TART, and it is strongly recommended that users only use the most recent version of TART 2002 and its data files.
Date: June 6, 2003
Creator: Cullen, D E
Partner: UNT Libraries Government Documents Department

Synthesis Strategies and a Study of Properties of Narrow and Wide Band Gap Nanowires

Description: Various techniques to synthesize nanowires and nanotubes as a function of growth temperature and time were investigated. These include growth of nanowires by a chemical vapor deposition (CVD) system using vapor-liquid-solid (VLS) growth mechanism and electro-chemical synthesis of nanowires and nanotubes. Narrow band gap InSb Eg = 0.17 eV at room temp) nanowires were successively synthesized. Using a phase diagram, the transition of the nanowire from metallic- semiconducting- semi-metallic phase was investigated. A thermodynamic model is developed to show that the occurrence of native defects in InSb nanowires influenced by the nanowire growth kinetics and thermodynamics of defect formation. Wide band gap ZnO (Eg = 3.34 eV) and In2O3 (3.7 eV) were also synthesized. ZnO nanowires and nanotubes were successfully doped with a transition metal Fe, making it a Dilute Magnetic Semiconductor of great technological relevance. Structural and electronic characterizations of nanowires were studied for different semiconducting, metallic and semi-metallic nanowires. Electron transport measurements were used to estimate intrinsic material parameters like carrier concentration and mobility. An efficient gas sensing device using a single In2O3 nanowire was studied and which showed sensitivity to reducing gas like NH3 and oxidizing gas like O2 gas at room temperature. The efficiency of the gas sensing device was found to be sensitive to the nature of contacts as well as the presence of surface states on the nanowire.
Date: May 2014
Creator: Sapkota, Gopal
Partner: UNT Libraries

Trajectory versus probability density entropy

Description: In this article, the authors show that the widely accepted conviction that a connection can be established between the probability density entropy and the Kolmogorov-Sinai (KS) entropy is questionable.
Date: 2001
Creator: Bologna, Mauro; Grigolini, Paolo; Karagiorgis, Markos & Rosa, Angelo
Partner: UNT College of Arts and Sciences

Transport-Depletion Desalination Pilot Plant

Description: From Summary: "The transport-depletion data obtained by the Southern Research Institute and by the Bureau of Reclamation at Denver, Colorado and at Webster, South Dakota, was reviewed. This data review made it possible to develop a design methodology for the pilot plant, and to identify the additional data required to adequately predict the performance of a transport-depletion stack."
Date: April 1971
Creator: Redman, Ralph
Partner: UNT Libraries Government Documents Department

Air Transport

Description: Report presenting the development in air transport that has taken place since civil aviation between England and Europe started at the end of August 1919. The primary subjects explored include the character of loads on aircraft, routes operated, results in passengers carried and efficiency of the service, costs of the service, question of subsidies, and probable future developments.
Date: 1924
Creator: Page, F. Handley
Partner: UNT Libraries Government Documents Department

Implication of the Transport Equation for the Semiempirical Treatment of Shields

Description: Note presenting a revision of the semiempirical method of dealing with shields by treating them as composed of layers by taking the angular distribution of the radiation into account and by making use of the transport equation. The method is illustrated by consideration of the effect upon neutrons of a thick nonabsorbing shield of high atomic weight.
Date: March 1952
Creator: Schwed, Philip
Partner: UNT Libraries Government Documents Department

The Technical Development of the Transport airplane: Report of the Aero-Technical Conference of the Scientific Association for Aeronautics, March 5, 1919

Description: The abolition of military qualifications gives free scope to new technical possibilities in the development of transport airplanes. This report notes the various considerations that must be made when designing aircraft to meet the needs of commercial passengers. Comfort and safety must be emphasized.
Date: April 1921
Partner: UNT Libraries Government Documents Department

The Employment of Airships for the Transport of Passengers: Indications on the Maximum Limits of Their Useful Load, Distance Covered, Altitude and Speed

Description: It was a conclusion of this detailed study of the practicality of using airships for carrying passengers that, although slow, airships are capable of carrying useful loads over long distances. However, it is noted that there is a certain limit to the advantages of large cubature. Beyond a certain point, the maximum altitude of the airship goes on decreasing, in spite of the fact that the range of action in the horizontal plane and the useful load go on increasing. The possibility of rapid climb is an essential factor of security in aerial navigation in the case of storms, as is velocity.
Date: August 1921
Creator: Nobile, Umberto
Partner: UNT Libraries Government Documents Department

An analysis of accelerations, airspeeds, and gust velocities from three commercial operations of one type of medium-altitude transport airplane

Description: From Introduction: "Past analyses of data from the NACA V-G and the NACA VGH recorders (see, for example, refs. 1 and 2) have yielded information on the magnitude and frequency of occurrence of gust and maneuver accelerations, and the associated airspeeds and altitudes for several types of airplanes flown by different operators on various routes."
Date: March 1955
Creator: Coleman, Thomas L.; Copp, Martin R.; Walker, Walter G. & Engel, Jerome N.
Partner: UNT Libraries Government Documents Department

An analysis of acceleration, airspeed, and gust-velocity data from one type of four-engine transport airplane operated over two domestic routes

Description: From Introduction: "As part of a continuing study of the gust and load histories for transport airplanes (see, for example, refs. 1 and 2), samples of VGH records have been obtained from two four-engine commercial transport airplanes. The data samples represent 839 and 1,080 flight hours of operation on two transcontinental routes and cover operations up to an altitude of 25,000 feet."
Date: October 1955
Creator: Copp, Martin R. & Coleman, Thomas L.
Partner: UNT Libraries Government Documents Department

An analysis of the airspeeds and normal accelerations of Boeing S-307 airplanes in commercial transport operation

Description: From Introduction: "The present paper has been prepared to give the results of the analysis of the V-G records obtained from three Boeing S-307 airplanes operating in Caribbean region and the northern part of South America during the period from 1940 to 1944."
Date: September 1946
Creator: Peiser, A. M. & Walker, W. G.
Partner: UNT Libraries Government Documents Department

An analysis of the airspeeds and normal accelerations of Douglas DC-3 airplanes in commercial transport operation

Description: From Introduction: "The present report is the second prepared to give the results of an analysis of V-G data from commercial transport airplanes. The present report is concerned with an analysis of data obtained with Douglas DC-3 airplanes flying over three transcontinental routes in the United States."
Date: September 1946
Creator: Peiser, A. M.
Partner: UNT Libraries Government Documents Department

Scale dependence of the effective matrix diffusion coefficient:some analytical results

Description: Matrix diffusion is an important process affecting solutetransport in fractured rock, and the matrix diffusion coefficient is akey parameter for describing this process. Previous studies haveindicated that the effective matrix-diffusion coefficient values,obtained from a number of field tracer tests, are enhanced in comparisonwith local values and may increase with test scale. In thiscommunication, we develop analytical expressions for the effective matrixdiffusion coefficient for two simple fracture-matrix systems, anddemonstrate that heterogeneities in the rock matrix at different scalescontribute to the scale dependence of the effective matrix diffusioncoefficient.
Date: May 30, 2005
Creator: Liu, H. H.; Zhang, Y. Q. & Molz, F. J.
Partner: UNT Libraries Government Documents Department

Improvements in release probability by using an overpack. [Obsolete munitions]

Description: An analysis was performed to determine the probability of an unconfined release of hazardous material as a consequence of being involved in a severe transportation accident. Two packaging scenarios were considered: (1) material was palletized and placed in a standard aluminum sided trailer, and (2) the same material was placed in an overpackage. In addition to truck, both rail and air transport were also considered. Several release categories were defined ranging from minor to very large, and the effectiveness of the overpackage to reduce the probability of unconfined release was evaluated for each type of release category. The results are applicable to the transport of radioactive materials in similar overpackages. The potential accident scenarios for a pallet of obsolete munitions were identified using a fault-free methodology.
Date: January 1, 1986
Creator: Rhyne, W.R.; Ashwood, T.L. & Shappert, L.B.
Partner: UNT Libraries Government Documents Department

TART 2000: A Coupled Neutron-Photon, 3-D, Combinatorial Geometry, Time Dependent, Monte Carlo Transport Code

Description: TART2000 is a coupled neutron-photon, 3 Dimensional, combinatorial geometry, time dependent Monte Carlo radiation transport code. This code can run on any modern computer. It is a complete system to assist you with input Preparation, running Monte Carlo calculations, and analysis of output results. TART2000 is also incredibly FAST; if you have used similar codes, you will be amazed at how fast this code is compared to other similar codes. Use of the entire system can save you a great deal of time and energy. TART2000 is distributed on CD. This CD contains on-line documentation for all codes included in the system, the codes configured to run on a variety of computers, and many example problems that you can use to familiarize yourself with the system. TART2000 completely supersedes all older versions of TART, and it is strongly recommended that users only use the most recent version of TART2000 and its data files.
Date: November 22, 2000
Creator: Cullen, D.E
Partner: UNT Libraries Government Documents Department

Recent advances in neutral particle transport methods and codes

Description: An overview of ORNL`s three-dimensional neutral particle transport code, TORT, is presented. Special features of the code that make it invaluable for large applications are summarized for the prospective user. Advanced capabilities currently under development and installation in the production release of TORT are discussed; they include: multitasking on Cray platforms running the UNICOS operating system; Adjacent cell Preconditioning acceleration scheme; and graphics codes for displaying computed quantities such as the flux. Further developments for TORT and its companion codes to enhance its present capabilities, as well as expand its range of applications are disucssed. Speculation on the next generation of neutron particle transport codes at ORNL, especially regarding unstructured grids and high order spatial approximations, are also mentioned.
Date: June 1, 1996
Creator: Azmy, Y.Y.
Partner: UNT Libraries Government Documents Department

Interfacial Charge Transport in Organic Electronic Materials: the Key to a New Electronics Technology

Description: This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The primary aim of this project is to obtain a basic scientific understanding of electrical transport processes at interfaces that contain an organic electronic material. Because of their processing advantages and the tunability of their electronic properties, organic electronic materials are revolutionizing major technological areas such as information display. We completed an investigation of the fundamental electronic excitation energies in the prototype conjugated polymer MEH-PPV. We completed a combined theoretical/experimental study of the energy relation between charged excitations in a conjugated polymer and the metal at a polymer/metal interface. We developed a theoretical model that explains injection currents at polymer/metal interfaces. We have made electrical measurements on devices fabricated using the conjugated polymer MEH-PPV a nd a series of metals.
Date: June 4, 1999
Creator: Smith, D.L.; Campbell, I.H.; Davids, P.S.; Heller, C.M.; Laurich, B.K.; Crone, B.K. et al.
Partner: UNT Libraries Government Documents Department

Impacts of Humic Injection Experiments on the South Oyster Field Research Site

Description: A closure plan for the South Oyster Focus Area (SOFA) is being implemented to assess the impacts of a series of experimental injections of microorganisms, tracers and chemical amendments on the chemical and physical properties of the aquifer. The proposed research addresses environmental monitoring of humic substances injected into the aquifer, as described in the Site Closure Plan for the South Oyster Field Research Site. The goal of the research is to demonstrate that the dissolved organic matter (DOM) in the groundwater at and downgradient from the injection site has returned to a pre-injection �baseline� conditions with respect to either the concentration or chemical composition of the DOM. For clarity, the humic solution injected during the experiment will be referred to as �humic injectate.� The term �DOM� will refer to the organic material recovered in the groundwater, which includes the autochthonous groundwater DOM as well as any of the humic injectate remaining in the groundwater. Specific objectives include: � Estimate the amount of humic material remaining in the aquifer at the completion of the push-pull experiment and the potential for environmental impacts due to release of humics retained on the sediments. � Monitor the DOM concentrations in groundwater over time at the injection well and at sampling locations within the potential downgradient plume of the injected tracers. � Evaluate the chemical composition of the DOM to determine whether the injection experiment had an impact of the chemical properties of the aquifer. The product of this research will be a contribution to the Site Closure Report documenting the impact of the humic experiments on the aquifer. Return of the aquifer to a �baseline� conditions will be achieved if the DOM concentrations in the groundwater are determined over the course of the research to have decreased to the pre-injection level, or if ...
Date: April 27, 2004
Creator: McCarthy, John F.
Partner: UNT Libraries Government Documents Department