CERN Document Server

In order to describe quantum heat engines, here we systematically study isothermal and isochoric processes for quantum thermodynamic cycles. Based on these results the quantum versions of both the Carnot heat engine and the Otto heat engine are defined without ambiguities. We also study the properties of quantum Carnot and Otto heat engines in comparison with their classical counterparts. Relations and mappings between these two quantum heat engines are also investigated by considering their respective quantum thermodynamic processes. In addition, we discuss the role of Maxwell's demon in quantum thermodynamic cycles. We find that ...

CERN Document Server

A process has been proposed to increase the efficiency of an ideal Otto cycle via a quantum heat engine that has no cooler reservoir. We show that such a process is not feasible.

Energy Technology Data Exchange (ETDEWEB)

This paper reports progress in the fabrication and characterization of an array of 1nm-scale colloidal particles (i.e., quantum-dot array) that can be operated to execute nontrivial and innovative computations, possibly including quantum logic. We discuss the actual fabrication of 2-nm metal clusters as an example of possible quantum dot implementation. Innovative and unconventional paradigms underlie the different stages of this work. For example, regular array geometry is achieved by directing appropriately derivatized metal clusters to preselected locations along a stretched strand of an engineered DNA sequence.

Energy Technology Data Exchange (ETDEWEB)

This book presents papers on internal combustion engines. Topics considered include the influence of partial suppression of heat rejection on performance and emissions, duothermic combustion, turbochargers made of sintered silicon nitrides, heat flux, low heat rejection engines, exhaust energy recovery, combustion chamber insulation, computerized simulation, heat transfer, friction, hoop stress effects, and bonding ceramics and metals.

Energy Technology Data Exchange (ETDEWEB)

The experimental survey about the heat transfer between the working fluid and the combustion chamber wall with a direct injection diesel engine has shown the production of a soot layer with increasing loads on the combustion chamber wall. Because the combustion process of methanol occurs without the formation of wall deposits, the same engine spark ignitioned with methanol at the same conditions has shown a higher heat transfer coefficient. Because the heat losses do not only depend on the heat transfer coefficient but also on the driving temperature difference between the working fluid and the combustion chamber wall, the methanol engine with corresponding process management showed lower heat losses than the diesel engine at nearly the same load. (orig./HW)

Energy Technology Data Exchange (ETDEWEB)

The possibility of switching the heat transfer consists of varying heat transfer surfaces and making the heat transfer temporarily more intensive. Heat tubes prove to be particularly suitable, which must be exposed to a heat carrier fluid or removed from its effect for switching the heat transfer. This report gives a survey of the possibilities of switching heat flows and for making the heat transfer more intensive. Further, the report contains a survey of patents limited to heat transfer in the fields of cooling internal combustion engines and exhaust systems. (orig.) With 17 figs., 183 refs.

Energy Technology Data Exchange (ETDEWEB)

The invention concerns a device for the energy-saving heating of fuel in the supply pipe to an internal combustion engine to regain energy from the fuel itself, particularly but not exclusively for a Diesel engine. A part of the quantity of heat added to the fuel between the tank and the injection nozzles is given up by excess fuel not to the tank, but to the fuel lifted upstream of the injection pump. The device is characterised by the fact that it has a heat exchanger, which absorbs heat from the fuel at the level of the injection pump or upstream of it, and takes this to the fuel above the injection pump. The heat exchanger is preferably mounted upstream of a filter and close to it. A bridging pipe, which may be integrated in the heat exchanger, permits the heat exchanger to be short-circuited ...

Energy Technology Data Exchange (ETDEWEB)

In this paper coating developments for advanced gas turbine engines (diffusion aluminide coatings, overlay coatings, and ceramic thermal barrier coatings) were desorbed, a selection of current metallic coatings was made and their performance as outlined. Finally coating developments for advanced diesel engines with a view to improved turbocharging or to low heat rejection engines (adiabatic diesel concept) were dealt with. (IHOE).

Energy Technology Data Exchange (ETDEWEB)

Since information has been regarded os a physical entity, the field of quantum information theory has blossomed. This brings novel applications, such as quantum computation. This field has attracted the attention of numerous researchers with backgrounds ranging from computer science, mathematics and engineering, to the physical sciences. Thus, we now have an interdisciplinary field where great efforts are being made in order to build devices that should allow for the processing of information at a quantum level, and also in the understanding of the complex structure of some physical processes at a more basic level. This thesis is devoted to the theoretical study of structures at the nanometer-scale, 'nanostructures', through physical processes that mainly involve the solid-state and quantum optics, in order to propose reliable schemes for the processing of ...

Energy Technology Data Exchange (ETDEWEB)

Resulting of the remarkably growth on economical development in each countries of Asia, ceramics low heat rejection engines are paid attention as a technique corresponding with the third oil shock which is presumed in near future. On the other hand, in order to construct the low heat rejection engines, using the quite different property materials from metals which called ceramics, it is necessary to determine design and combustion method fitted to the feature of this different kind materials. Though the development of ceramics low heat rejection engines have been given up in the world, recently, the development of ceramics engines is again required for the purpose of realizing an engine with low fuel consumption. Authors have successfully solved the problems, such as the disuse of cooling system, the improvement of ...

Energy Technology Data Exchange (ETDEWEB)

Experimental investigations are being conducted on a single-cylinder direct-injection diesel engine to examine the transient heat transfer characteristics. Transient temperature data from stationary locations in the piston and cylinder head were used as the basis for determining the transient heat flux rates. Transient surface temperature was measured using the thin film thermocouples. At first, the transient heat flux rates calculated from the analysis method used in this paper were compared with the results from FEM. The results showed good agreement. Using this analysis method, the transient heat flux rates were calculated. The tests were performed at 1200 rpm with constant air flow. The parameters that were varied included the fuel rate and injection timing. Based on these results, the present paper discusses the mechanism of heat rejection in a ...

Energy Technology Data Exchange (ETDEWEB)

This paper presents an investigation into the feasibility and potential advantages of a small scale Miller cycle natural gas engine for applications such as domestic combined heat and power systems. The Miller cycle engine is compared to a standard Otto cycle engine using cycle analyses and multidimensional simulation, and basic engine design implications are discussed. It is found that the Miller cycle engine has a potential for improved fuel efficiency, but at the cost of a reduced power to weight ratio. A fuel efficiency advantage of 5{yields}10% compared to a standard Otto cycle engine appears possible, however it is stated that further investigations, in particular into the topic of engine friction, are required in order to validate the findings. (author)

CERN Document Server

Quantum man

Energy Technology Data Exchange (ETDEWEB)

In order to find the solution to the problem of depletion of conventional fuels and environmental pollution caused by them, new design concepts such as low heat rejection engines and alternate fuel vehicles have started to appear. The present study deals with the concept of alternate fuel vehicle using hydrogen as a fuel. Results of analytical study to minimize heat loss during the power stroke of a hydrogen fueled spark ignition engine have been presented. Effect of various design and operating parameters on heat losses using a simulation model developed by the authors have also been presented. The results shall be helpful in designing efficient hydrogen fuelled spark ignition engines. (orig.)

Energy Technology Data Exchange (ETDEWEB)

In the interests of fuel economy in motor vehicles, this article discusses the importance of waste heat recovery and then goes on the explore options such as hybrid electric cars, thermal engines with low loss platforms, pure electric vehicles and fuel cell vehicles. (UK)

Energy Technology Data Exchange (ETDEWEB)

A solar thermal powered aircraft powered by heat energy from the sun. A Rankine-Brayton hybrid cycle heat engine is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller or other mechanism for enabling sustained free flight. The Rankine-Brayton engine has a thermal battery, preferably containing a lithium-hydride and lithium mixture, operably connected to it so that heat is supplied from the thermal battery to a working fluid. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for ...

UK PubMed Central (United Kingdom)

Quantum computing is a quickly growing research field. This article introduces the basic concepts of quantum computing, recent developments in quantum searching, and decoherence in a possible quantum...Full Text Available

International Nuclear Information System (INIS)

The report presents the results of experimental studies conducted to provide a description of the conditions which lead to the occurrence of critical heat flux (CHF), in Combustion Engineering (C-E) fuel assemblies using the C-E standard spacer grid. A CHF correlation is presented which is based on CHF data obtained in tests with electrically heated rod bundles representative of the C-E 14 x 14 and 16 x 16 array fuel assemblies. The results reported are for a uniform axial heat flux distribution. The experiments were conducted in the Medium Pressure Heat Transfer Flow Loop at the Chemical Engineering Research Laboratories at Columbia University.

Energy Technology Data Exchange (ETDEWEB)

In this paper compression and power stroke cycles for a 4 stroke cycle spark ignition engine modified by extending the connecting rod to simulate purely sinusoidal piston motion are analyzed over a range of operating speeds and are compared with those of a similar conventional engine. Heat release rate is estimated for both engines using a simple Wiebe function with the functional parameters found via a simplex curve fitting method is used in conjunction with experimental pressure curves. It is shown that the functional parameters which represent the combustion and duration of fuel burn are slightly larger over the range of operation in the sinusoidal engine while the shape factor remains largely the same.

Energy Technology Data Exchange (ETDEWEB)

The fuel-injection system of the Niigata 6L 16X-AG dual-fuel engine is structured to steadily supply injected fuel during diesel-engine operation, and to distribute oil at a low rate to all the cylinders during gas-engine operation. The dual-fuel engine is started by the diesel engine operation and is changed over to gas-engine operation when the load increases. This change over is done automatically with a link mechanism. Regarding the gas-supply system, the changing pressure of supply gas is controlled by a pressure control valve which is stable and most adequate for the engine. The dual-fuel engine has the following features: (1) a high compression ratio is adopted, which reduces fuel consumption and thermal efficiently; (2) if the supply of gas decreases or stops, while continuing loaded operations, it can ...

Energy Technology Data Exchange (ETDEWEB)

Experimental investigations are being conducted on a single-cylinder direct-injection diesel engine to examine the effects of combustion chamber specifications and swirl ratios on the heat release and transient heat transfer characteristics. Heat rejection was examined on the basis of heat release calculations using cylinder pressure time histories. Transient surface temperature data obtained from stationary locations in the piston and cylinder head were used as the basis for determining the transient heat flux rates. The results showed good agreement with the heat rejection calculated from cylinder pressure data and that transient heat flux in a piston cavity was reduced with the larger cavity diameter and a higher swirl ratio. On the other hand, a transient heat flux in a piston head was not ...

Energy Technology Data Exchange (ETDEWEB)

This book is not a traditional handbook. Engineers in industry need up-to-date, accessible information on the applications of heat and mass transfer. This book is the answer. Contents include: (1) emphasis on applications in thermal design and computer solutions of thermal engineering problems; (2) an introduction to the use of the Second Law of Thermodynamics in analysis, optimization, and economics; (3) information on topics of current interest--in a form convenient and accessible to the average engineer; (4) three chapters of background material--enough to review the basic principles needed to understand specific thermal applications; and (5) extensive treatment of computational tools and numerical analysis.

Energy Technology Data Exchange (ETDEWEB)

The concentric circular annular duct is a common geometry in many fluid flow and heat transfer devices. For the purpose of heat transfer augmentation, fins are often employed in the annular region, and such finned ducts find wide application in compact heat exchangers (5, 6). The analysis of flow and heat transfer in this geometry is, therefore, quite important from an engineering standpoint. For fully developed conditions, the problem has already been analyzed (7-10). However, no results are available for the developing flow in the entrance region. It is with this latter problem that the present paper is concerned.

International Nuclear Information System (INIS)

This book is organized under the following headings: Electrohydrodynamic heat transfer augmentation; Forced convection augmentation and heat transfer control; Turbulent heat transfer; Thermal problems in the environment; Energy conversion systems; Measurement, visualization, and imaging; Thermal problems in space technology; and Thermal properties.

Energy Technology Data Exchange (ETDEWEB)

Today, as a result of increase in oil prices, limited fossil fuel resources, environmental consideration and global warming, the methyl ester fuels have been focused on alternative fuels. Methyl ester fuels can be used more efficiently in low heat rejection engines (LHR), in which the temperature of combustion chamber is increased by creating a thermal barrier. In this study, the piston, cylinder head, exhaust and inlet valves of a diesel engine were coated with the ceramic material Al{sub 2}O{sub 3}-TiO{sub 2} by the plasma spray method. Thus, a thermal barrier was provided for the parts of the combustion chamber with these coatings. The effects of corn oil methyl ester that produced by the transesterification method, and No. D2 fuels' performance and exhaust emissions' rate were studied by using equal in every respect coated and uncoated engines. Tests were performed on the uncoated ...

CERN Document Server

The physical foundations of a variety of emerging technologies --- ranging from the applications of quantum entanglement in quantum information to the applications of nonequilibrium bulk and interface phenomena in microfluidics, biology, materials science, energy engineering, etc. --- require understanding thermodynamic entropy beyond the equilibrium realm of its traditional definition. This paper presents a rigorous logical scheme that provides a generalized definition of entropy free of the usual unnecessary assumptions which constrain the theory to the equilibrium domain. The scheme is based on carefully worded operative definitions for all the fundamental concepts employed, including those of system, property, state, isolated system, environment, process, separable system, system uncorrelated from its environment, and parameters of a system. The treatment considers also systems with movable internal walls and/or ...

Science.gov (United States)

A paraboloidal dish solar thermal power plant produces electrical energy by a two-step conversion process. The collector subsystem is composed of a two-axis tracking paraboloidal concentrator and a cavity receiver. The concentrator focuses intercepted sunlight (direct, normal insolation) into a cavity receiver whose aperture encircles the focal point of the concentrator. At the internal wall of the receiver the electromagnetic radiation is converted to thermal energy. A heat engine/generator assembly, which is mounted directly behind th receiver, then converts the thermal energy captured by the receiver to electricity. Developmental activity has been concentrated on relatively small power modules which employ 11- to 12-m-diam dishes to generate nominal power levels of approximately 20 kW. A comparison of advanced heat engines for use on the dish power module is presented in terms of the performance ...

Energy Technology Data Exchange (ETDEWEB)

The influence of engine operating variables on the performance, emissions and heat release in a compression ignition engine operating in normal diesel and dual-fuel modes (with natural gas fuelling) was investigated. Substantial reductions in NO{sub x} emissions were obtained with dual-fuel engine operation. There was a corresponding increase in unburned hydrocarbon emissions as the substitution of natural gas was increased. Brake specific energy consumption decreased with natural gas substitution at high loads but increased at low loads. Experimental results at fixed pilot injection timing have also established the importance of intake manifold pressure and temperature in improving dual-fuel performance and emissions at part load. (Author)

Energy Technology Data Exchange (ETDEWEB)

This work presents an analysis of the operation of a multi-cylinder, tubro charged, indirect injection diesel engine from a second-law analysis point of view. For this purpose, a single-zone thermodynamic model following the filling and emptying modelling technique is developed. A second-law analysis is performed in all parts of the diesel engine plant, which provides all the existing availability terms and accounts for the evaluation of every component`s irreversibilities. A complete second-law terms tabulation is given for the maximum speed-full load operation case, which is compared with its first-law counterpart. A detailed parametric study is performed in all parts of the diesel engine plant comprising the effects of speed and load on the availability terms in a range that covers the whole operation of the engine under turbocharged action. Various second-law (availability) terms such as indicated ...

UK PubMed Central (United Kingdom)

From the gross conservation laws of thermodynamics in a convecting material we derive a bound on the ratio of the rate of production of mechanical or magnetic energy to the rate of internal radioactive...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Kawasaki Heavy Industries, Ltd. has developed a gas turbine combined cycle and cogeneration plant computer aided engineering (CAE) system, which creates cycle heat balance automatically on given configurations of gas turbines, heat recovery boilers, steam turbines and auxiliaries. The system can predict the performance of the plant as a function of control set points, loads, process steam requirements and ambient conditions, which enables accurate and fast design of gas turbine combined cycle and cogeneration plants. (author)

Energy Technology Data Exchange (ETDEWEB)

Tests have been conducted on a special compression ignition research engine to investigate the effects of gaseous fuels on the ignition delay in dual fuel engines. Diesel oil, n-heptane, or cetane were used as pilot fuels, and hydrogen, carbon monoxide, or methane were inducted in the intake manifold. Induction of nitrogen was used as a reference to eliminate the influence of changes in oxygen concentration and specific heats. Helium was inducted in additional tests. From the results of a number of parameter variations, the cylinder charge temperature (determined by intake temperature and compression ratio), the pilot fuel amount, and the flow of combustible gas were found to have the most significant influence on the ignition delay.

CERN Document Server

Motional heating of ions in micro-fabricated traps is a challenge hindering experimental realization of large-scale quantum processing devices. Recently a series of measurements of the heating rates in surface-electrode ion traps characterized their frequency, distance, and temperature dependencies, but our understanding of the microscopic origin of this noise is still vague. In this work we develop a theoretical model for the electric field noise which is associated with a random distribution of adsorbed atoms on the trap electrode surface. By using first principle calculations of the fluctuating dipole moments of the adsorbed atoms we evaluate the distance, frequency and temperature dependence of the resulting electric field fluctuation spectrum.Our theory calculates the noise spectrum beyond the standard scenario of two-level fluctuators, by incorporating all the relevant vibrational states. The $1/f$ noise is shown to ...

Energy Technology Data Exchange (ETDEWEB)

A gas injection diesel engine was developed as an approaching measure to the diversification of fuel. Contrary to the usual low pressure gas application engine, this engine applies a so-called diffuse combustion method, in which high pressure (24.7Mpa) gas fuel is injected directly in the cylinder and is ignited and combusted by a little pilot fuel injected almost at the same time. The engine have following features. As a principle, it can attain the same heat efficiency and output rate as a diesel engine in any load range. It is excellent in responsibility to load fluctuation. There is no internal leakage of gas fuel to the scavenging chamber (the crank chamber) in the compression stroke. Not only a wide range of mixed combustion of gas fuel and heavy oil fuel, but also single combustion of heavy oil is possible. It is, therefore, drawing attention as an ...

Energy Technology Data Exchange (ETDEWEB)

A phenomenological model of the heat transfer in direct injection diesel engines was developed. Utilizing the thermodynamic results of a combustion model as an input, the model is able to predict the temporal variation of the heat losses from the cylinder gas to the cylinder walls. Additionally, the division into isothermal combustion chamber subsurfaces allows the consideration of the spatial variation of the wall heat fluxes. The physical mechanisms such as flow dependent convection, heat radiation due to hot soot particles and isolation effects of deposited soot layers are described in detail. Thus the effects of these mechanisms on the overall heat transfer can be studied. The heat transfer model was verified successfully by the comparison to measured wall heat fluxes in a single-cylinder direct injection diesel ...

Energy Technology Data Exchange (ETDEWEB)

Power output of a hydrogen-diesel dual-fuel engine is limited by the onset of knock as the percentage of heat input derived from hydrogen increased beyond a certain limit. Earlier work carried out at the Internal Combustion Engines Laboratory, Indian Institute of Technology, Madras, indicates that this knock sets in when the induced hydrogen exceeds about 60% of input energy at a pilot diesel quantity of 30% of full load diesel amount. At higher rates of hydrogen induction, the richer hydrogen-air mixture is more prone to knocking. Hardly any information is available on the possibilities of improving the knock limited power output of a hydrogen-diesel dual-fuel engine. Water can serve as a powerful internal coolant in decreasing the unburned mixture temperature because of its high latent heat. This paper presents the results of our investigation on improving the knock limited power ...

Energy Technology Data Exchange (ETDEWEB)

The factors influencing premixed burning and the importance of premixed burning on the exhaust emissions from a small high-speed direct-injection diesel engine were investigated. The characteristics of premixed and diffusion burning were examined using a single-zone heat-release analysis. The mass of fuel burned in premixed combustion was found to be linearly related to the product of engine speed and ignition-delay time and to be essentially independent of the total amount of fuel injected. Accordingly, the premixed-burned fraction increased with increasing engine speed, with decreasing fuel-air ratio and with retarding injection timing. The hydrocarbon emissions did not correlate well with the premixed-burned fraction. In contrast, the oxides of nitrogen emissions were found to increase with decreasing premixed-burned fraction, indicating that diffusion burning, and not premixed burning, is the ...

Energy Technology Data Exchange (ETDEWEB)

A mathematical model was developed to predict the penetration of a transient fuel spray, the temporal and spatial distribution of air-fuel mixture before the end of ignition delay and the subsequent pressure rise during combustion in a Direct-Injection Diesel Engine with and without swirl. The model accounts for the non-isothermal and non-isobaric character of processes during fuel injection resulting from continuous motion of the piston. The effects of various engine operating variables on spray were studied and graphically presented. The calculated spray penetration with and without crossflow of air is compared with the available experimental data of other researchers with good agreement. The model can predict the rate of combustible-mixture formation, the rate of heat release and cylinder pressure as a function of time in direct injection (DI) diesel engine. A single-cylinder D.I. research diesel ...

Energy Technology Data Exchange (ETDEWEB)

Vehicle heating requires a substantial amount of energy. Engines in conventional cars produce enough waste heat to provide comfort heating and defogging/defrosting, even under very extreme conditions. Electric vehicles (EVs), however, generate little waste heat. Using battery energy for heating may consume a substantial fraction of the energy storage capacity, reducing the vehicle range, which is one of the most important parameters in determining EV acceptability. Water vapor generated by the vehicle passengers is in large part responsible for the high heating loads existing in vehicles. In cold climates, the generation of water vapor inside the car may result in water condensation on the windows, diminishing visibility. Two strategies are commonly used to avoid condensation on windows: windows are kept warm, and a large amount of ambient ...

Energy Technology Data Exchange (ETDEWEB)

In January 1981, a dual-fuel engine of type 8L52/55 ADG, with the highest cylinder rating of all four-stroke gas engines currently available, succesfully completed its test run on M.A.N.s test bed at Augsburg. The engine can be operated either on Diesel oil or on gas and pilot oil and can be switched from Diesel to gas operation or vice versa at any load during operation. In gas operation, the engine works on the pilot injection principle. By changing from pulse-pressure to constant-pressure turbocharging, matching the charge-air pressure, improving mixture formation and optimising the injection system, M.A.N. has succeeded in achieving a high power output while reducing the heat consumption in gas operation almost to its level in Diesel operation. A close look is taken at the design features which distinguish the dual-fuel engine from the 52/55 A Diesel ...

International Nuclear Information System (INIS)

We report the observation of quantum interference in superfluid 4He. The interferometer, an analog of a dc-superconducting quantum interference device (SQUID), employs a recently reported phenomenon wherein superfluid 4He exhibits Josephson frequency oscillations in an array of submicron apertures. An interference pattern is generated by reorienting the loop of the superfluid 'SQUID' with respect to the Earth's rotation vector, thereby varying the rotation flux in the loop. The experiment is performed at 2 K, a temperature 2000 times higher than previously achieved with superfluid 3He. We find that the interference exists not only when the aperture array current-phase relation is a sinusoidal function characteristic of the Josephson effect, but also at lower temperatures where it is linear and oscillations occur by phase slips. The modest requirements for the interferometer (2 K cryogenics and fabrication of apertures at the level of 100 nm) ...

Energy Technology Data Exchange (ETDEWEB)

Engineering materials for use in low heat rejection engines are required to function under stringent tribological conditions. Severe wear damage and high friction between the components of the tribosystem limit the number of potential materials suitable for such application conditions. The superalloys X-750 and 188 are composed of alloying elements that not only promote a high mechanical and chemical stability but may also result in a reduced wear rate and friction coefficient at elevated temperatures. As a part of the DOE-ECUT Tribology program at Argonne, the present study was undertaken to evaluate the tribological characteristics of these alloys that will also be utilized as the substrates for ion beam deposited lubricous coatings. A wear test rig that crudely simulated the sliding conditions between a piston ring and a cylinder liner in an operating engine was utilized for friction and wear ...

British Library Electronic Table of Contents (United Kingdom)

An Otto cycle engine with internal and external irreversibilities of friction and heat leakage, in which the heat transfer between the working fluid and the environment obeys linear phenomenological heat transfer law [q ?? ?(T ?1)], is studied in this paper. The optimal piston motion trajectory for maximizing the work output per cycle is derived for the fixed total cycle time and fuel consumed per cycle. Optimal control theory is applied to determine the optimal piston trajectories for the cases of with and without piston acceleration constraint on each stroke and the optimal distribution of the total cycle time among the strokes. The optimal piston motion with acceleration constraint for each stroke consists of three segments, including initial maximum acceleration and final maximum decel...

International Nuclear Information System (INIS)

The ISI (In-Service Inspection) system has been developed so as to maintain the structural integrity of heat transfer tubes in the primary pressurized water cooler in the HTTR (High Temperature Engineering Test Reactor). This system consists of eddy current probes, ultra-sonic probes, insertion and extraction units, positioning unit and so on. Verification and performance tests of the developed ISI system were carried out using mock-up heat transfer tubes in the primary pressurized water cooler. The constitution of the system, R and D results of the inspection probes, and verification and performance test results of the ISI system for heat transfer tubes are described in this paper. (author)

Energy Technology Data Exchange (ETDEWEB)

Vol. 4 comprises 23 papers on the following subjects: General aspects (effects in the human/environment systeme); Trends in space HVAC engineering; Heating systems engineering; Air quality and thermal comfort. [German] Der Tagungsband 4 enthaelt 23 Aufsaetze. Sie sind in die folgenden vier Themen-Bloecke aufgeteilt: Allgemeines (Wirkungen in der wahrgenommenen Wirkungssystem: Mensch-Umwelt); Entwicklungen in der Raumlufttechnik; Heizungstechnik; Luftqualitaet und Behaglichkeit. (AKF)

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared

International Nuclear Information System (INIS)

A theoretical scheme for quantum secure direct communication (QSDC) is proposed, where a three-qubit symmetric W state functions as a quantum channel. Two legitimate communicators can transmit their secret information by using quantum teleportation and local measurements.

Energy Technology Data Exchange (ETDEWEB)

This paper describes the basic principles underlying the operation of low heat loss engines and the magnitude of the efficiency improvements that are theoretically achievable. The effect of varying degrees of thermal insulation on various operating parameters is examined in some detail, as is the relationship between degree of insulation and ceramic coating thickness. The effect on ceramic materials of severe surface temperature oscillations and the resultant thermal stress gradients is also discussed. In the following section, the paper describes methods of construction adopted both for ceramic inserts and coatings, and rig tests for the assessment of thermal fatigue under both load and firing cycling. The paper does not attempt to draw any general conclusions.

Energy Technology Data Exchange (ETDEWEB)

In support of the efforts to apply ceramics to advanced heat engines, a study is being performed of the performance of ceramics at the ring/cylinder interface of advanced (low heat rejection) engines. The objective of the study, managed by the Oak Ridge National Laboratory, is to understand the basic mechanisms controlling the wear of ceramics and thereby identify means for applying ceramics effectively. Attempts to operate three different zirconias, silicon carbide, silicon nitride, and plasma-sprayed ceramic coatings without lubrication have not been successful because of excessive friction and high wear rates. Silicon carbide and silicon nitride perform well at ambient temperatures with fully formulated mineral oil lubrication, but are limited to temperatures of 500F because of the lack of suitable liquid lubricants for higher temperatures.

Energy Technology Data Exchange (ETDEWEB)

In view of current trends in motor car development, the author investigates the increasing conflict between higher comfort and lower fuel consumption. The conflict results mainly from insufficient cooling water heating with consumption-optimized engines. So far, it was never necessary to analyze heat flow after cold starting and heat-up of the powertrain, to develop strategies for heat storage and distribution, to remove heat sinks and to use components multifunctionally. The contribution shows that a general heat management strategy for the whole vehicle will result in high potential fuel savings and improved thermal comfort. Using the example of a latent heat store, heating strategies for the engine and transmission system on the one hand and the passenger compartment on the ...

Energy Technology Data Exchange (ETDEWEB)

In the GE 7FDL single cylinder research diesel engine, in-cylinder high-speed photographic studies were conducted on coal-water slurry (CWS) fuel combustion. Distinct flames of pilot and CWS combustion were noticed. It was proven that the coal fuel burns after piston impingement and secondary atomization. Agglomerated particles will develop when combustion conditions are not favorable. Cylinder pressure data were simultaneously recorded for each film frame. Heat release data can thus be produced for each photo study. Most of the findings of earlier combustion studies on engine performance were confirmed.

International Nuclear Information System (INIS)

The authors present a summary of the present state of the quantum field theory of tachyons. (W.D.L.).

CERN Document Server

An introduction to recent developments in several active topics at the interface between algebra, geometry, topology and quantum field theory

Science.gov (United States)

An electric power generating apparatus is described, including: a solar collector; a primary thermal loop including primary thermal fluid; a cavity receiver to receive reflected solar energy from the solar reflector, convert the solar energy into thermal energy, and transmit the thermal energy to the primary thermal fluid by heating the primary thermal fluid not to exceed a given temperature, the given temperature being substantially equal to 700 F; a Stirling engine receiving the primary thermal fluid heated by the cavity receiver, including means to generate mechanical power and means to generate electrical power from the means to generate mechanical power.

Energy Technology Data Exchange (ETDEWEB)

Total thermal resistance of ground heat exchanger (GHE) is comprised of that of the soil and inside the borehole. The thermal resistance of soil can be calculated using the linear source theory and cylindrical source theory, while that inside the borehole is more complicated due to the integrated resistance of fluid convection, and the conduction through pipe and grout. Present study evaluates heat exchange rate per depth of GHE by calculating the total thermal resistance, and compares different methods to analyze their similarities and differences for engineering applications. The effects of seven separate factors, running time, shank spacing, depth of borehole, velocity in the pipe, thermal conductivity of grout, inlet temperature and soil type, on the thermal resistance and heat exchange rate are analyzed. Experimental data from several real geothermal heat pump (GHP) ...

Science.gov (United States)

Lawrence Livermore, Sandia Livermore and Los Alamos National Laboratories have a joint project to develop an optimized hydrogen fueled engine for series hybrid automobiles. The major divisions of responsibility are: system analysis, engine design and kinetics modeling by LLNL; performance and emission testing, and friction reduction by SNL; computational fluid mechanics and combustion modeling by LANL. This project is a component of the Department of Energy, Office of Utility Technology, National Hydrogen Program. We report here on the progress on system analysis and preliminary engine testing. We have done system studies of series hybrid automobiles that approach the PNGV design goal of 34 km/liter (80 mpg), for 384 km (240 mi) and 608 km (380 mi) ranges. Our results indicate that such a vehicle appears feasible using an optimized hydrogen engine. The impact of various on-board storage options on fuel ...

International Nuclear Information System (INIS)

This paper will review code and standard and the safety related features of major components of Monju: Components of the Reactor Coolant Boundary; Components of the Reactor Shurdown Systems; Components of the Decay Heat Removal Systems; Components of the Engineered Safety Features; Other Safety Related Components. Their relationship to the system or plant function is emphasized, in reviewing these components.

Energy Technology Data Exchange (ETDEWEB)

There are a number of characteristics exhibited by ceramic materials that may provide potential benefits for the reciprocating internal combustion engine. However, the brittle nature of these materials together with a variability in strength has created difficulties in applying ceramic materials to the engine environment. Although a wide range of physical properties is available from contemporary ceramic materials, a material offering consistently high strength has yet to be developed. For sliding-contact applications, desirable characteristics include good wear resistance, low friction, ability to join metals and good heat dissipation. Test results have shown that cam/follower components with cast iron cam sliding on a silicon nitride follower exhibit very low wear rates. The application of silicon carbide to face seals has also shown substantial reductions in both friction and wear when compared with conventional ...

Energy Technology Data Exchange (ETDEWEB)

High-performance polysilicon thin-film transistors (TFT`s) are fabricated using an excimer laser to recrystallize the undoped channel and dope the source-drain regions. Using a technique the authors call grain engineering they are able to control grain microstructure using laser parameters. Resulting polysilicon films are obtained with average grain sizes of {approximately}4--9 {micro}m in sub-100 nm thick polysilicon films without substrate heating during the laser recrystallization process. Using a simple four-mask self-aligned aluminum top-gate structure, they fabricate TFT`s in these films. By combining the grain-engineered channel polysilicon regions with laser-doped source-drain regions, TFT`s are fabricated with electron mobilities up to 260 cm{sup 2}/Vs and on/off current ratios greater than 10{sup 7} To their knowledge, these devices represent the highest performance laser-processed TFT`s reported to date ...

CERN Document Server

When quantum gravity is used to discuss the big bang singularity, the most important, though rarely addressed, question is what role genuine quantum degrees of freedom play. Here, complete effective equations are derived for isotropic models with an interacting scalar to all orders in the expansions involved. The resulting coupling terms show that quantum fluctuations do not affect the bounce much. Quantum correlations, however, do have an important role and could even eliminate the bounce. How quantum gravity regularizes the big bang depends crucially on properties of the quantum state.

Energy Technology Data Exchange (ETDEWEB)

The paper is Part 2 of the study on the thermodynamic and thermoeconomic analyses of trigeneration system with a gas-diesel engine. In Part 1, thermodynamic and thermoeconomic methodologies for such a comprehensive analysis were provided, while this paper applies the developed methodology to an actual TRIGEN system with a rated output of 6.5 MW gas-diesel engine installed in the Eskisehir Industry Estate Zone, Turkey. Energy and exergy efficiencies, equivalent electrical efficiency, the Public Utility Regulatory Policies Act (PURPA) efficiency, fuel energy saving ratio, fuel exergy saving ratio and other thermodynamic performance parameters are determined for the TRIGEN system. The efficiencies of energy, exergy, PURPA and equivalent electrical efficiency of the entire system are found to be 58.97%, 36.13%, 45.7% and 48.53%, respectively. For the whole system and its components, exergetic cost allocations and various exergoeconomic performance ...

Energy Technology Data Exchange (ETDEWEB)

We report the performance of a commercial recuperated micro gas turbine on biomass producer gas and mixtures of biomass producer gas with natural gas. The biomass producer gas, obtained by gasification at 850{sup o}C with air at atmospheric pressure, contains about 7% H2, 17% CO, 15% CO2, 4% CH4, 2% other hydrocarbons, 2% H2O, and a balance of N2 and Ar from air. It has a net heating value of about 6 MJ/(Nm{sup 3}). The micro gas turbine delivers full power (30 kW{sub e}) on gas mixtures with a net heating value of at least 15 MJ/(Nm{sup 3}). For gas of lower heating value, the maximum fuel gas flow allowed by the fuel control unit limits the attainable power. At reduced power, the lower limit for stable operation is a net heating value of about 8 MJ/(Nm{sup 3}). The gross efficiency of the micro gas turbine depends on the output power but not on the gas heating value, within our ...

Energy Technology Data Exchange (ETDEWEB)

Changes in the physical and chemical processes during the ignition delay period of a gas-fueled diesel engine (dual-fuel engine) due to the increased admission of the gaseous fuels and diluents are examined. The extension to the chemical aspects of the ignition delay with the added gaseous fuels and the diluents into the cylinder charge is evaluated using detailed reaction kinetics for the oxidation of dual-fuel mixtures at an adiabatic constant volume process while employing n-heptane as a representative of the main components of the diesel fuel. In the examination of the physical aspects of the delay period, the relative contributions of changes in charge temperature, pressure, physical properties, pre-ignition energy release, heat transfer, and the residual gas effects due to the admission of the gaseous fuels are discussed and evaluated. It is shown that the introduction of gaseous fuels and diluents into the diesel ...

Energy Technology Data Exchange (ETDEWEB)

Energy savings performance contracting (ESPC) is now receiving greater attention as a means of implementing large-scale energy conservation projects in housing. Opportunities for such projects exist for military housing, federally subsidized low-income housing, and planned communities (condominiums, townhomes, senior centers), to name a few. Accurate prior (to construction) estimates of the energy savings in these projects reduce risk, decrease financing costs, and help avoid post-construction disputes over performance contract baseline adjustments. This paper demonstrates an improved method of estimating energy savings before construction takes place. Using an engineering model calibrated to pre-construction energy-use data collected in the field, this method is able to predict actual energy savings to a high degree of accuracy. This is verified with post-construction energy-use data from a geothermal heat pump ESPC at Fort Polk, Louisiana. ...

Science.gov (United States)

Within the framework of the cluster approach and the semiempirical SCF MO LCAO method in the CNDO/BW valence approximation, possible pathways have been compared for the dehydroxylation of aluminosilicate systems. It has been shown that dehydroxylation as a result of splitting of a water molecule from an acidic bridge hydroxyl group and a more basic terminal group Al-OH is the most energyfavorable. Apparently, such a dehydroxylation pathway is primarily characteristic for amorphous aluminosilicates. Typical of crystalline aluminosilicates at moderate heat-treating temperature is dehydroxylation through splitting of a water molecule from an acidic bridge hydroxyl group and a neutral Si-OH group; at higher temperatures, there is a possible pathway of dehydroxylation of highsilica zeolites as a result of condensation of two acidic surface hydroxyls.

International Nuclear Information System (INIS)

Apart from conventional phase transitions driven by the thermal effects, quantum phase transitions generated by quantum fluctuations have their own mechanisms that are reflected in critical phenomena. Quantum phase transitions have an origin from spontaneous symmetry breaking commonly to thermal phase transitions. Even in this case, inherent quantum fluctuations substantially modify and yield new aspects. Quantum phase transitions have, however, another mechanism caused by topology changes, which gives completely new characters. Recently, a mechanism which connects these two has been found. Proimities from first-order transitions and phase separatins as well as from multiphase coexistence also generate characteristic and unconventional quantum criticalities. Understanding novel quantum criticalities offers a firm basis of recent active ...

International Nuclear Information System (INIS)

This paper discusses the concept of controllable subspace for open quantum dynamical systems. It is constructively demonstrated that combining structural features of decoherence-free subspaces with the ability to perform open-loop coherent control on open quantum systems will allow decoherence-free subspaces to be controllable. This is in contrast to the observation that open quantum dynamical systems are not open-loop controllable. To a certain extent, this paper gives an alternative control theoretical interpretation on why decoherence-free subspaces can be useful for quantum computation.

Energy Technology Data Exchange (ETDEWEB)

Performance and emissions data were gathered on a normally aspirated single cylinder DI engine with various combinations of ceramic coatings installed. Thin ceramic thermal barrier coatings were applied to the piston crown and bowl, the head and valves, and the cylinder liner. The coated piston and head were run singly and in combination with the cylinder liner to investigate the effects of these different coated surfaces on emissions and performance. Coating the piston crown alone results in generally lower cylinder pressure, lower brake specific fuel consumption and lower NO(x) emission compared to the baseline engine. Soot emission is typically increased below 2000 RPM and decreased above 2000 RPM. Coating the head alone reduces cylinder pressure, but generally increases specific fuel consumption and NO(x) and soot emission. The KIVA-II code was used to model the Hydra engine with the thermal coatings. The computer ...

Energy Technology Data Exchange (ETDEWEB)

In addition to dependable starting - even at extreme sub-zero temperatures - the starting behaviour of modern commercial vehicle diesel engines is increasingly being evaluated on the basis of HC emissions in the starting and warm-up phases. To improve their performance in this respect, most small and medium-sized diesel engines (with a capacity of 3 to 12 litres) are therefore equipped with intake air heating systems. As an alternative to high-performance, fuel-burning flame start systems, the automotive industry supplier Beru has now developed a new type of self-regulating electric heating element which not only ensures dependable starting with short heating times but also allows drastic reductions in HC emissions. (orig.) [Deutsch] Das Startverhalten moderner Nutzfahrzeug-Dieselmotoren wird, ergaenzend zum Hauptmerkmal des sicheren Starts auch bei extremen Minustemperaturen, ...

Energy Technology Data Exchange (ETDEWEB)

Several natural gas vehicles have been built as part of Ford's Alternative Fuel Demonstration Fleet. Two basic methods, compressed gas (CNG), and liquified gas (LNG) were used. Heat transfer danger and the expense and special training needed for LNG refueling are cited. CNG in a dual-fuel engine was demonstrated first. The overall results were unsatisfactory. A single fuel LNG vehicle was then demonstrated. Four other demonstrations, testing different tank weights and engine sizes, lead to the conclusion that single fuel vehicles optimized for CNG use provide better fuel efficiency than dual-fuel vehicles. Lack of public refueling stations confines use to fleet operations.

British Library Electronic Table of Contents (United Kingdom)

Experiments have been conducted to study the effect of injection pressure on the combustion process and exhaust emissions of a direct injection diesel engine fueled with Orange Skin Powder Diesel Solution (OSPDS). Earlier investigation by the authors revealed that 30% OSPDS was optimum for better performance and emissions. In the present investigation the injection pressure was varied with 30% OSPDS and the combustion, performance and emissions characteristics were compared with those of diesel fuel. The different injection pressures studied were 215bar, 235bar and 255bar. The results showed that the cylinder pressure with 30% OSPDS at 235bar fuel injection pressure, was higher than that of diesel fuel as well as at other injection pressures. Similarly, the ignition delay was longer and wi...

Energy Technology Data Exchange (ETDEWEB)

Magnetite nanoparticles with high self-heating capacity and low toxicity characteristics are a promising candidate for cancer hyperthermia treatment. In order to achieve minimum dosage to a patient, magnetic nanoparticles with high heating capacity are needed. In addition, the influence of physiological factors on the heat capacity of a material should be investigated in order to determine the feasibility. In this study, magnetite nanoparticles coated with lauric acid were prepared by co-precipitation of Fe{sup 3+}:Fe{sup 2+} in a ratio of 2:1, 5:3, 3:2, and 4:3, and the pH was controlled using NaOH. Structural and magnetization characterization by means of X-ray diffractometry (XRD) and a superconducting quantum interference device (SQUID) revealed that the main species was Fe{sub 3}O{sub 4} and further showed that most of the nanoparticles exhibited superparamagnetic properties. All of the magnetic ...

Energy Technology Data Exchange (ETDEWEB)

This contribution is intended to introduce the principles of quantum computing to those who always wanted to know about quantum computing but never dared to ask. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

CERN Document Server

In this work we study the dephasing mechanism of a double quantum-dot system, which includes two electrons and a nearby quantum point contact (QPC) as a measurement device. We obtain that the QPC-induced decoherence is on time scales of microseconds. We also find that the electrons will be delocalized after continuous measurement, irrespectively of the initial conditions, and the frequent repeated measurements will localize the system, which is consistent with the quantum Zeno effect. Further, we consider the situation that the double quantum-dot system is irradiated by a microwave field.

Energy Technology Data Exchange (ETDEWEB)

In March 1980, administrators of Clarkson College of Technology made a decision to convert the college's downtown heating plant to one that can rely on wood as a fuel. The decision was prompted by high costs of oil and gas needed to heat the downtown campus. In October 1981, a wood-fired plant with a rated steam production capacity of 10,500 lb/hour went into a trial operation. The plant cost $685,742 which includes $625,642 for material and labour and $60,100 for engineering. In the 1981 to 1982 heating season, it supplied 55 percent of the steam needs of the downtown campus with a wood fuel consumption of 2,857 tons. Under normal operation, the wood-fired plant will require about 4,500 tons of green wood chips per heating season. The investment in the wood-fired plant is expected to have a real rate of return (after discounting inflation) in the range of 20 to 23 percent ...

Energy Technology Data Exchange (ETDEWEB)

This report documents the Proceedings of the 1995 Oil Heat Technology Conference and Workshop, held on March 22-23 at Brookhaven National Laboratory (BNL), and sponsored by the U.S. Department of Energy - Office of Building Technologies (DOE-OBT), in cooperation with the Petroleum Marketers Association of America. This Conference, which was the ninth held since 1984, is a key technology transfer activity supported by the ongoing Combustion Equipment Technology (Oil-Heat R&D) program at BNL, and is aimed at providing a forum for the exchange of information among international researchers, engineers, manufacturers, and marketers of oil-fired space-conditioning equipment. The objectives of the Conference were to: (1) Identify and evaluate the state-of-the-art and recommend new initiatives for higher efficiency, a cleaner environment, and to satisfy consumer needs cost-effectively, reliably, and safely; (2) Foster ...

Science.gov (United States)

The results of this research centered on the experimental studies of a single superconducting persistent current qubit, the implementation of type-II algorithms using these qubits, and the proposal for adiabatic quantum computing using these qubits. The m...

Science.gov (United States)

For coupled quantum wires and dots, tunneling effects and coherent transport for quantum computing are being studied. In 2D systems, electron-hole bilayers for exciton...

Science.gov (United States)

... In this paper we review the recent results concerning physical aspects of QWlP and QDIP operation focusing primarily on the electron transport ...

Energy Technology Data Exchange (ETDEWEB)

There is considerable interest in the use of silicon devices as qubits for quantum computing. The existence of nuclear spin in a silicon isotope and the complex band structure of silicon are unfavourable for this application of silicon devices. (viewpoint)

CERN Document Server

A novel algebraic topology approach to supersymmetry (SUSY) and symmetry breaking in quantum field and quantum gravity theories is presented with a view to developing a wide range of physical applications. These include: controlled nuclear fusion and other nuclear reaction studies in quantum chromodynamics, nonlinear physics at high energy densities, dynamic Jahn-Teller effects, superfluidity, high temperature superconductors, multiple scattering by molecular systems, molecular or atomic paracrystal structures, nanomaterials, ferromagnetism in glassy materials, spin glasses, quantum phase transitions and supergravity. This approach requires a unified conceptual framework that utilizes extended symmetries and quantum groupoid, algebroid and functorial representations of non-Abelian higher dimensional structures pertinent to quantized spacetime topology and state space geometry of ...

Energy Technology Data Exchange (ETDEWEB)

A 1 MWe power plant using waste wood fuel is to be installed at a US Marine Corps base, which will supply all wood from a landfill site. The core energy conversion technology is a down-draft gasifier supplying approximately 150 Btu/scf gas to both spark ignition and diesel dual-fuel engine-generator sets. Features of the plant design include: (1) grinding wood fuel from a wide range of waste resources, (2) specialized screening for fines removal, (3) complete tar and other waste product control without landfill disposal, and (4) use of process heat for bulk fuel drying, gasifier air pre-heating, and wastewater evaporation.

Energy Technology Data Exchange (ETDEWEB)

Composting is once again gaining interest among ecological engineers in view of greener industrial and residential activities. Uniform composting is needed to ensure decomposition and to keep the whole system at the same composting stage. A homogeneous temperature must be maintained throughout the media. A bioreactor design consisting of a heater core made of copper tubing was designed and tested. Two four-inch holes were made at the top and bottom of the barrel to allow air to flow through the system and promote aerobic composting. Once composting began and temperature increased, the water began to flow through the copper piping and the core heat was distributed throughout the medium. Three thermocouples were inserted at different heights on a 200 litre plastic barrel fitted with the aforementioned apparatus. Temperature variations were found to be considerably lower when the apparatus was operated with the heat ...

Energy Technology Data Exchange (ETDEWEB)

The 1996/`97 buyers` guide comprises ten chapters: 1. List of suppliers; 2. Waste management, effluents, sewage systems; 3. Water supply, hydroengineering; 4. Chemistry, petrochemistry; 5. Chemical engineering; 6. Food industry, biotechnology; 7. Paper and cellulose industry; 8. Natural gas industry, natural gas supply; 9. Power plant engineering, power systems, district heating; 10. Air conditioning and refrigeration engineering. (orig.) [Deutsch] Der vorliegende Einkaufsfuehrer 1996/97 ist in zehn Kapiteln gegliedert. Diese sind: 1. Firmenverzeichnis 2-11 2. Entsorgungs-/Abwassertechnik, Klaeranlagen 12-15 3. Wasserversorgung, Wassertechnik 16-18 4. Chemie, Petrochemie 19-22 5. Verfahrenstechnik 23-26 6. Lebensmittelindustrie, Biotechnik 27-29 7. Papier-, Zeluloseindustrie 30-31 8. Erdgasindustrie, -versorgung 32 9. Kraftwerkstechnik, Energieanlagen, Fernwaerme 33-34 10. Kaelte-/Klimatechnik 35-36. ...

Energy Technology Data Exchange (ETDEWEB)

Industrial facilities offer a wide variety of design challenges to engineers, including the mechanical engineers who design the HVAC, the process, exhaust, and other required mechanical systems; the mechanical contractors who install and maintain the systems (and who also may do design work); and the owners` engineers who are responsible for the day-to-day operation of their facilities. Along with the responsibility to see that all systems function as intended is the responsibility to ensure that all worker health concerns are addressed. These include heat stress avoidance and the proper control of harmful substances. The services of industrial hygienists may be required to ensure this. These may be independent consultants or the staff members of mechanical design firms. In addition, it is not unusual for major corporations that own manufacturing plants to have staff industrial hygienists. The ...

Energy Technology Data Exchange (ETDEWEB)

The search for alternative fuels and new fuel resources is a top priority for Turkey, as is the case in the majority of countries throughout the world. The fuel policies pursued by governmental or civil authorities are of key importance in the success of alternative fuel use, especially for widespread and efficient use. Following the 1973 petroleum crisis, many users in Turkey, especially in transportation sector, searched for alternative fuels and forms of transportation. Gasoline engines were replaced with diesel engines between the mid-1970s and mid-1980s. In addition, natural gas was introduced to the Turkish market for heating in the early 1990s. Liquid petroleum gas was put into use in the mid-1990s, and bio-diesel was introduced into the market for transportation in 2003. However, after long periods of indifference governmental action, guidance and fuel policies were so weak that they did not make sense. ...

International Nuclear Information System (INIS)

Large scale steam storage power generation, one of the new energy storage systems for the future of inflexible electric power sources consisting of nuclear and coal power plants has been studied on the subjects of the systems to be attached to coal and nuclear power units, of the definition of storage efficiency and of the vertical steam storage vessel technology. Steam storage power generation may be hopeful for its higher efficiency similarly defined as of pumped storage plants while high temperature heat storage and the internal structure of large vertical steam storage vessel (accumulator) need to be developed. (author).

Energy Technology Data Exchange (ETDEWEB)

As recently as 1950, 30% of the world's population lived in urban areas. By the year 2030, 60% of the world's population will live in cities, according to the United Nations 'World Population Prospects Revision Report' (2001). Urbanization is quickly transitioning communities from natural rural vegetation to man-made urban engineered infrastructure. This anthropogenic-induced change has manifested itself in microscale and mesoscale increases in temperatures in comparison to adjacent rural regions which is known as the Urban Heat Island Effect. The resultant change causes potentially adverse consequences for local and global communities. One of the great challenges facing our current generation of scientists and engineers is how to support the growth of new and existing urban centers in a sustainable manner. This is even more pronounced in arid regions, which will sustain the greatest rate ...

CERN Document Server

We define the Bloch spectrum of a quantum graph to be the collection of the spectra of a family of Schr\\"odinger operators parametrized by the cohomology of the quantum graph. We show that the Bloch spectrum determines the Albanese torus, the block structure and the planarity of the graph. It determines a geometric dual of a planar graph. This enables us to show that the Bloch spectrum completely determines planar 3-connected quantum graphs.

International Nuclear Information System (INIS)

We discuss the use of active control to reduce mirror position fluctuations at the quantum level. We have shown in a recent experiment that it is possible to reduce the thermal noise of a mirror by measuring and controlling its motion with an optomechanical sensor based on a high-finesse optical cavity. This approach can be extended to lock the mirror motion at the quantum level, and to suppress the quantum effects of radiation pressure in interferometric measurements such as gravitational-wave detectors. The sensitivity improvement is furthermore independent of losses in the interferometer.

Science.gov (United States)

DC Field, Value, Language.

International Nuclear Information System (INIS)

... Abstract only 1063-7869 v. 44(10) CLASSICAL AND QUANTUM MECHANICS,

British Library Electronic Table of Contents (United Kingdom)

[image omitted

CERN Document Server

Here we show that self-propulsion in quantum vacuum may be achieved by rotating or aggregating magneto-electric nano-particles. The back-action follows from changes in momentum of electro-magnetic zero-point fluctuations, generated in magneto-electric materials. This effect may provide new tools for investigation of the quantum nature of our world. It might also serve in the future as a "quantum wheel" to correct satellite orientation in space.

Energy Technology Data Exchange (ETDEWEB)

This paper surveys the publications available in the literature concerning the application of the second-law of thermodynamics to internal combustion engines. The availability (exergy) balance equations of the engine cylinder and subsystems are reviewed in detail providing also relations concerning the definition of state properties, chemical availability, flow and fuel availability, and dead state. Special attention is given to identification and quantification of second-law efficiencies and the irreversibilities of various processes and subsystems. The latter being particularly important since they are not identified in traditional first-law analysis. In identifying these processes and subsystems, the main differences between second- and first-law analyses are also highlighted. A detailed reference is made to the findings of various researchers in the field over the last 40 years concerning all types of internal combustion ...

Energy Technology Data Exchange (ETDEWEB)

A theoretical study of an exciton confined in a quantum ring is presented. The quantum ring is described as a two-dimensional circular quantum dot with a repulsive core, which is modelled with the help of two Gaussian functions. We have applied the variational method and investigated the evolution of the low-energy exciton spectrum with the change of the confinement potential. The calculations have been performed for the recently produced self-assembled ring-shaped InGaAs quantum dots. We have shown that the repulsive core strongly increases the radiative transition probability from the exciton ground state at the expense of the decreasing probability of the transitions from the excited states. This effect results from the orthogonality properties of the exciton wavefunctions, which are specific to the quantum-ring confinement potential. We have studied the characteristic features ...

Energy Technology Data Exchange (ETDEWEB)

Analyses of process system properties were continued for important chemical materials involved in the several processes under consideration for semiconductor and solar cell grade silicon production. Major activities were devoted to physical, thermodynamic and transport property data for silicon. Property data are reported for vapor pressure heat of vaporization, heat of sublimation, liquid heat capacity and solid heat capacity as a function of temperature to permit rapid usage in engineering. Chemical engineering analysis of the HSC process (Hemlock Semiconductor Corporation) for production of silicon was initiated. The process is based on hydrogen reduction of dichlorosilane (DCS) to produce the polysilicon. The chemical vapor deposition reaction for DCS is faster in rate than the conventional process route which utilizes trichlorosilane (TCS) as the silicon ...

Index Scriptorium Estoniae

Heliplaadist

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Energy Technology Data Exchange (ETDEWEB)

A quantum computer would put the latest PC to shame. Not only would such a device be faster than a conventional computer, but by exploiting the quantum-mechanical principle of superposition it could change the way we think about information processing. However, two key goals need to be met before a quantum computer becomes reality. The first is to be able to control the state of a single quantum bit (or 'qubit') and the second is to build a two-qubit gate that can produce 'entanglement' between the qubit states. (U.K.)

CERN Document Server

Big Bang nucleosynthesis requires a fine balance between equations of state for photons and relativistic fermions. Several corrections to equation of state parameters arise from classical and quantum physics, which are derived here from a canonical perspective. In particular, loop quantum gravity allows one to compute quantum gravity corrections for Maxwell and Dirac fields. Although the classical actions are very different, quantum corrections to the equation of state are remarkably similar. To lowest order, these corrections take the form of an overall expansion-dependent multiplicative factor in the total density. We use these results, along with the predictions of Big Bang nucleosynthesis, to place bounds on these corrections.

Science.gov (United States)

This is the homepage of "an Australian multi-university collaboration undertaking research on the fundamental physics and technology of building, at the atomic level, a solid state quantum computer in silicon together with other high potential implementations." Although attempts to develop a quantum computer have met with limited success, the centre has substantial resources invested in advancing toward practical uses of quantum computing technology. The site provides a very good introduction to the principles and implications of quantum computing, as well as details about various research projects underway at the Australian universities. Links to conference and journal papers produced by members of the centre, many from 2003, are also provided.

Energy Technology Data Exchange (ETDEWEB)

Products having balanced melting point and decomposition temperature have been developed by employing nylon 6T fundamental molecular structure and selected copolymer components, Arlen being one of the products. It has heat resistance as good as that of super-engineering plastics, low water absorption, and excellent cost-performance which can be used for normal injection molding machines. The unit price per kilogram is low when its high heat resistance is taken into consideration. The coefficient of water absorption is as low as about 1/3 of that of nylon 66, and it can be considered to be a low water absorbing amide. The molding temperature is from 320[degree]C to 350[degree]C, the decomposition temperature is 395[degree]C at 2% weight decreasing temperature, and normal injection molding can be employed. It has excellent soldering resistance, high temperature rigidity, dimensional stability, water absorbing coefficient, as ...

Energy Technology Data Exchange (ETDEWEB)

A mathematical model of a mineral melting cupola furnace for stone wool production has been developed for improving cupola operation. The 1-D, first-engineering-principles model includes mass and heat balances for the gas phase, five solid phases, and four liquid phases. The gas and solid/liquid phases flow countercurrently. Seven chemical reactions account for the conversions of coke, iron oxide, limestone, and gaseous species. The heterogeneous reactions of coke conversion are limited by both kinetics and mass transport. Heat transfer between phases is modeled including both convection and radiation. The model predicts gas concentrations; mass flow rates; and temperature profiles of the solid, melt, and gas in the cupola, as well as heat loss to the water-cooled walls. Inputs to the model include the coke, rock, and blast air properties, the blast air amount, and the coke percentage in the charge. The ...

Energy Technology Data Exchange (ETDEWEB)

Full text of publication follows: The heat transfer and flow in narrow channels has lots of advantages such as compact structure, high efficiency, design flexibility and so on. So it is widely used in the fields such as the new reactor core plate elements, the once-through stream generator, compact heat exchangers as well as electronic components. In recent years, more strong attentions have been attracted to the thermal-hydraulic characteristics and mechanism of the two-phase flow in narrow channels. As the flow regime characteristics of two-phase flow is fundamental one of them, the research on the two-phase flow regimes and the regime transitions in horizontal rectangular narrow heated channels can provide theoretical foundation and engineering directions to the whole research on the thermal-hydraulic characteristics and mechanism of the two-phase flow in narrow channels. The characteristics of ...

Science.gov (United States)

The photopumped phonon-assisted laser operation (612 nm, 77 K) of a high-gapIn/sub 1/minus//ital y//(Al/sub /ital x//Ga/sub 1/minus//ital x//)/sub /ital y//P quantum wellheterostructure (QWH) lattice matched to GaAs (/ital y/approx.0.5) is identified usinga single rectangular sample that is shifted in its heat sinking from (a) low/ital Q/ when clamped onto Au (bare edges) to (b) high /ital Q/ when furthercompressed into Au with all four edges reflecting. For the low-/ital Q/ QWH samplephotopumped in a spot (partially photopumped), phonon-assisted laser operation(abrupt threshold, narrow spectrum) is observed on closely spaced end-to-endlaser modes ..delta../ital E/=/h bar/..omega../sub LO/approx.45--47 meV below the lowestconfined-particle transitions. For the /ital same/ sample shifted tohigh /ital Q/, edge-to-edge laser operation across the sample on confined-particletransitions is ''turned on'' also, thus ...

Energy Technology Data Exchange (ETDEWEB)

The pathway to hydrogen generation entirely from renewable energy and material sources probably goes by a transitional period with the utilization of hybrid fossil/renewable integrated systems. Solar steam reforming of methane is set in this context, specifically suited for a country like Italy whose actual energy policy is mainly based on the imported NG, but also characterized by convenient solar radiation levels in the Southern Regions. A new solar SMR process is being developed by ENEA, using molten nitrates as solar heat carriers and storage medium at about 550 C. The potential of this process have been proved theoretically by process simulation studies. Engineering and experimental activities aimed to the development of a prototype apparatus are now in progress in ENEA's laboratories. It is remarkable that the developed technology (MS powered SMR) can find interesting impact in the in industrial chemistry wherever it is ...

CERN Document Server

The Quantum Mechanics Conceptual Survey (QMCS) is a 12-question survey of students' conceptual understanding of quantum mechanics. It is intended to be used to measure the relative effectiveness of different instructional methods in modern physics courses. In this paper we describe the design and validation of the survey, a process that included observations of students, a review of previous literature and textbooks and syllabi, faculty and student interviews, and statistical analysis. We also discuss issues in the development of specific questions, which may be useful both for instructors who wish to use the QMCS in their classes and for researchers who wish to conduct further research of student understanding of quantum mechanics. The QMCS has been most thoroughly tested in, and is most appropriate for assessment of (as a posttest only), sophomore-level modern physics courses. We also describe testing with students in ...

CERN Document Server

A new mathematical framework is formulated to derive the effective equations of motion for the constrained quantum system which possesses an internal clock. In the realm close to classical behavior, the quantum evolution is approximated by a finite system of coupled but ordinary differential equations adhered to the weakly imposed Hamiltonian constraint. For the simplified version of loop quantum cosmology in the Bianchi I model with a free massless scalar filed, the resulting effective equations of motion affirm the bouncing scenario predicted by the previous studies: The big bang singularity is resolved and replaced by the big bounces, which take place up to three times, once in each diagonal direction, whenever the directional density approaches the critical value in the regime of Planckian density. It is also revealed that back-reaction arises from the quantum corrections and modifies the precise ...

CERN Document Server

The study of quantum walk process has been widely divided into the two standard variants, the discrete-time quantum walk (DTQW) and the continuous-time quantum walk (CTQW). The connection between the two variants has been established by considering limiting value of the coin operation parameter in the DTQW and the coin degree of freedom is show to be unnecessary [26]. But the coin degree of freedom is an additional resource which can be exploited to control the dynamics of the QW process. In this paper we present a generic quantum walk (QW) model using a quantum coin-embedded unitary shift operation U_{C}. The standard version of the DTQW and the CTQW can be conveniently retrieved from this generic model retaining the features of the coin degree of freedom in both the variants.

Energy Technology Data Exchange (ETDEWEB)

The main problems with the use of neat vegetable oils in diesel engines are higher smoke levels and lower thermal efficiency as compared to diesel. The problem can be tackled by inducting a gaseous fuel in the intake manifold along with air. In this investigation, hydrogen is used as the inducted fuel and rubber seed oil (RSO), rubber seed oil methyl ester (RSOME) and diesel are used as main fuels in a dual fuel engine. A single cylinder diesel engine with rated output of 4.4 kW at 1500 rpm was converted to operate in the dual fuel mode. Dual fuel operation of varying hydrogen quantity with RSO and RSOME results in higher brake thermal efficiency and significant reduction in smoke levels at high outputs. The maximum brake thermal efficiency is 28.12%, 29.26% and 31.62% with RSO, RSOME and diesel at hydrogen energy share of 8.39%, 8.73% and 10.1%, respectively. Smoke is reduced from 5.5 to 3.5 BSU with RSOME and for RSO it ...

Energy Technology Data Exchange (ETDEWEB)

Several shield options were analyzed for the ITER conceptual design to minimize the nuclear responses in the toroidal field (TF) coils. The total nuclear heating in the physics phase and the insulator dose in the technology phase are the most critical parameters in the design process. The first shield option has type 316 stainless steel and water shielding material. Steel and water also serve as structural material and coolant, respectively. The second option is similar to the first except that borated water is used instead of ordinary water. The other two options include a small layer of lead or boron carbide (B{sub 4}C) at the back of the shield. The last three shield options were considered to reduce the nuclear heating in the toroidal field coils relative to the steel/water shield. An optimization process was performed taking into consideration the thermal-hydraulics and the engineering requirements to define the shield ...

Energy Technology Data Exchange (ETDEWEB)

The cooperative project was a joint development program between Ceradyne and Oak Ridge National Laboratory through Lockheed Martin Energy Research (LMER). Cooperative work was of benefit to both parties. ORNL was able to assess the effect of the microwave nitridation process coupled with gas-pressure sintering for fabrication of parts for advanced diesel engines. Ceradyne gained access to gelcasting expertise and microwave facilities and experience for the nitridation of SRBSN materials. The broad objective of the CRADA between Ceradyne and OIWL was to (1) examine the applicability of the gelcasting technology to fabricate parts from SRBSN, and (2) to assess the effect of the microwave nitridation of silicon process coupled with gas-pressure sintering for fabrication of parts for advanced diesel engines. The following conclusions can be made from the work performed under the CRADA: (1) Gelcasting is a viable method to fabricate SRBSN parts ...

International Nuclear Information System (INIS)

A 2007 report compiled by members of the armed services indicates that climate change presents a serious security threat to the American public as well as to United States military operations. It is likely that climate change will increase global tensions and competition for resources. This presentation discussed advanced research and technology programs conducted by the National Aeronautics and Space Administration (NASA). Scientists and engineers at NASA have developed a number of technologies that may contribute to American energy security. Advanced energy research and development programs initiated by the organization include advanced heat engines; wind turbines; batteries and electric cars; solar photovoltaics; and fuel cell technologies. NASA's aeronautics and space exploration program has several capabilities relevant to advanced wind power systems. A collaborative program is currently underway to develop airborne ...

Energy Technology Data Exchange (ETDEWEB)

Work on this coke oven gas cleaning demonstration project (CCT-II) this quarter has been focused on Phase IIB tasks, and include engineering, procurement, construction, and training. Additionally, plans for changes in the operating schedule of the coke plant that affect the demonstration project are described. Engineering efforts are nearly complete. Remaining to be finalized is an assessment of electrical heat tracing/insulation needs for pipe lines, assessment of fire protection requirements, and instrument modifications. Procurement of all major equipment items is complete, except for possible additions to fire fighting capabilities. Major focus is on expediting pipe and structural steel to the project site. Civil construction is complete except for minor pads and bases as required for pipe supports, etc. Erection of the hydrogen sulfide and ammonia scrubber vessels is complete. Installation of scrubber vessel internals ...

Energy Technology Data Exchange (ETDEWEB)

The objective of this Energy Engineering Analysis (EEA) for LSAAP is threefold: Develop a systematic plan of projects which will result in reducing energy consumption. Consider renewable energy sources with the objective of establishing an orderly procedure for reducing use of non-renewable energy sources. Determine the feasibility of Total Energy (TE), Selective Energy (SE), and Central Heating Plant (CHP) concepts using alternative fuels. In essence, an assessment of the entire energy picture at LSAAP was undertaken. This report is a summary of that effort. LSAAP was originally built during 1941 and 1942 as a shell loading plant for the Army. After World War II, the facility was deactivated until 1951 when it was reactivated as a Government Owned, Contractor Operated (GOCO) facility. Day and Zimmerman was selected as the operator in 1951 and has been the operating contractor ever since. Located just west of Texarkana, Texas, LSAAP encompasses ...

Energy Technology Data Exchange (ETDEWEB)

The proceedings of a workship of researchers and potential users of decomposed method fuel for Otto cycle engines are presented. The purpose of the meeting was to review the state-of-the-art. Proponents for its use state that by using exhaust waste heat to decompose the methanol, the resulting gaseous fuel constituents have more energy content than that in the original liquid. The drawbacks include the unapplicability during engine warmup and the fraction of automobile duty cycle related thereto, the reduced volumetric efficiency associated with any gaseous fuel, and the tradeoffs between improved thermal efficiency and reduced power output with lean fuel mixtures. There has always been a dilemma as to whether a decomposed methanol system is a variation on the application of methanol, of hydrogen, or both. However, the more immediate issue is whether use of methanol is liquid, decomposed or dual form is the most cost ...

International Nuclear Information System (INIS)

The Department of Nuclear Engineering and Fluid Mechanics in the University of the Basque Country (UPV-EHU), has done calculations for the proposed benchmark problem, in the frame of the 11th international meeting of the IAHR working group on advanced nuclear reactors thermal-hydraulics (Obninsk-Russian Federation, 5-9 July 2004). The purpose of the benchmark is to compare experimental and analytical results of some experiments carried out in the State Scientific Center of Russian Federation 'Institute of Physics and Power Engineering' (SSC RF IPPE). These experiments were held to research the cooling of pin bundles by liquid metals in reference to the core of Nuclear Reactors such as BREST. The analytical results have been done with the Computational Fluid Dynamics (CFD) code FLUENT. Temperature and velocity fields are the main variables considered for the comparison, and some assumptions has been made in order to simplify a complicate ...

Energy Technology Data Exchange (ETDEWEB)

The performance of binary geothermal power plants can be improved through the proper choice of a working fluid, and optimization of component designs and operating conditions. This paper reviews the investigations at the Idaho National Engineering Laboratory (INEL) which are examining binary cycle performance improvements: for moderate temperature (350 to 400 F) resources with emphasis on how the improvements may be integrated into design of binary cycles. These investigations are examining performance improvements resulting from the supercritical vaporization of mixed hydrocarbon working fluids and achieving countercurrent integral condensation with these fluids, as well as the modification of the turbine inlet state points to achieve supersaturated turbine vapor expansions. For resources where the brine outlet temperature is restricted, the use of turbine exhaust recuperators is examined. The baseline plant used to determine improvements in plant performance ...

International Nuclear Information System (INIS)

Using a new approach to quaternion mechanics based on De Broglie waves, it is shown that such a theory describes tachyons and that the quantum theory of tachyons should be a quaternionic one. (U.K.).

International Nuclear Information System (INIS)

We obtain a symmetry algebra for any unitary minimal model by using the representation of conformal field theories. This symmetry algebra can be interpreted as a quantum group. The generalization to non-unitary minimal models is direct. (orig.).

Energy Technology Data Exchange (ETDEWEB)

A new model for computations is considered which combines the quantum computer with the chaotic dynamics amplifier, based on the logistic map. We discuss the satisfiability problem and argue that the problem can, in principle, be solved in polynomial time if one uses the new model for computations.

Energy Technology Data Exchange (ETDEWEB)

In this paper method of constructing quasi-exactly solvable models of quantum mechanics is proposed. This method is based on the use of infinite-dimensional representations of simple and semi-simple Lie algebras.

UK PubMed Central (United Kingdom)

A quantum computer (QC) can operate in parallel on all its possible inputs at once, but the amount of information that can be extracted from the result is limited by the phenomenon of wave function...Full Text Available

International Nuclear Information System (INIS)

Considered is a new type of generalized asymptotic functions, which are not functionals on some space of test functions as the Schwartz distributions. The definition of the generalized asymptotic functions is given. It is pointed out that in future the particular asymptotic functions will be used for solving some topics of quantum mechanics and quantum theory.

Science.gov (United States)

This paper discusses the use of tracers as a reservoir engineering tool in fractured geothermal reservoirs. The principle concern in injecting cooler spent fluids into a fractured reservoir is that the fluids may move through high permeability channels and return to the production wells after contacting a relatively small volume of rock. As a consequence of this rapid transport, the fluids will be only partially reheated and after a short period time will effectively mine the heat from the limited volume of rock. The production wells will then experience a rapid and premature reduction in thermal output. Tracers can be used to infer the existence of high mobility conduits between injection and production wells and to monitor chemical changes of an injected fluid. Since tracer arrival precedes thermal breakthrough, tracer tests are a very useful forecasting tool.

Energy Technology Data Exchange (ETDEWEB)

Future power plants will be more fuel efficient, environmentally benign, and economical than current power plants. A high performance power system (HIPPS), based on a coal-fired combined cycle, is currently being developed. The corrosion and temperature-strength properties of currently available metallic materials limit the maximum efficiency of this cycle. Recently, ceramic matrix composites have shown promise in overcoming the design limitations on the future power plants. In particular, the high-temperature, and corrosion and erosion resistant properties of continuous fiber ceramic composites (CFCCs) will allow engineers to design high-temperature heat exchangers, cyclone vortex finder tubes, and other components. Research being performed to evaluate candidate materials for use in future power plants is discussed.

Science.gov (United States)

A 206-size hybrid (ceramic/steel) cylindrical roller bearing was tested in MIL-L-23699 C oil at several speeds and loads. Heat-generation data was collected and subsequently correlated with bearing-analysis software. Bearing-cage slip data was also collected at various oil-flow rates, oil temperatures, and with both MIL-L-7808 J and MIL-L-23699 C oils. The hybrid bearing was tested in MIL-L-23699 C oil for for 25 hours at 2220 N radial load and 1.08 MDN shaft speed. The hybrid bearing technology demonstrated in the report is applicable to the Integrated High Performance Turbine Engine Technology Initiative. 15 refs.

Energy Technology Data Exchange (ETDEWEB)

Analytical and numerical methods have been used in this investigation to model the behavior of geothermal systems under exploitation. The work is divided into three parts: (1) development of a numerical code, (2) theoretical studies of geothermal systems, and (3) field applications. A new single-phase three-dimensional simulator, capable of solving heat and mass flow problems in a saturated, heterogeneous porous or fractured medium has been developed. The simulator uses the integrated finite difference method for formulating the governing equations and an efficient sparse solver for the solution of the linearized equations. In the theoretical studies, various reservoir engineering problems have been examined. These include (a) well-test analysis, (b) exploitation strategies, (c) injection into fractured rocks, and (d) fault-charged geothermal reservoirs.

Energy Technology Data Exchange (ETDEWEB)

Geothermal budget actual amounts are shown for FY 1989 -1992, broken down by about 15 categories. Here, the main Program categories are: Exploration Technology, Drilling Technology, Reservoir Technology, Conversion Technology (power plants and materials), Industry-Coupled Drilling, Drilling Applications, Reservoir Engineering Applications, Direct Heat, Geopressured Wells Operation, and Hot Dry Rock Research. Here the title--Industry-Coupled Drilling--covered case studies of the Coso, CA, and Dixie Valley, NV, fields, and the Long Valley Exploratory Well (which had started as a magma energy exploration project, but reported here as a hydrothermal prospect evaluation well). (DJE 2005)

Energy Technology Data Exchange (ETDEWEB)

Metal machining facilities pose interesting design problems. This article provides an overview of key environmental control considerations and ways to deal with them. Machine shops offer a variety of environmental control challenges to mechanical engineers. Among the design problems that must be considered include: whether to provide space heating only or year-round air conditioning; temperature and relative humidity requirements; air cleanliness; exhaust air requirements; the type of HVAC system to be used; industrial waste and plumbing considerations; compressed air needs; and noise control. In addition, the designer must comply with worker health and safety and environmental protection regulations set forth by the National Institute of Safety and Health (NIOSH), OSHA, and EPA, as well as with any applicable state and local requirements.

International Nuclear Information System (INIS)

A preliminary design for a nuclear electric 'Space Tug' is proposed for use in conjunction with the American Space Shuttle for high energy missions. The vehicle would employ a SNAP 10A/2 or SNAP 8 nuclear reactor derivative for its power supply and slush hydrogen as the working fluid for the electrothermal thrusters. A thermodynamic conversion cycle would be employed for electrical power generation, for which the hydrogen working fluid would perform the duty of the heat sink. The cycle would eliminate the need for heavy waste radiators and improve the overall thermal efficiency. The vehicle promises a considerable payload advantage over a chemical recoverable Tug for geostationary missions. (orig.).

International Nuclear Information System (INIS)

Two avowable quantum communication schemes are proposed. One is an avowable teleportation protocol based on the quantum cryptography. In this protocol one teleports a set of one-particle states based on the availability of an honest arbitrator, the keys and the Einstein-Podolsky-Rosen pairs shared by the communication parties and the arbitrator. The key point is that the fact of the teleportation can neither be disavowed by the sender nor be denied by the receiver. Another is an avowable quantum secure direct communication scheme. A one-way Hash function chosen by the communication parties helps the receiver to validate the truth of the information and to avoid disavowing for the sender.

International Nuclear Information System (INIS)

The conventional treatment of quantum field theories including tachyons is presented, in particular the phi"4 theory. (W.D.L.).

Energy Technology Data Exchange (ETDEWEB)

Trapped ions are a near ideal system to study quantum information processing due to the high degree of control over the ion's external confinement and internal degrees of freedom. We demonstrate the key steps necessary for trapped ion quantum computing and focus on phonon-mediated entangling gates. We highlight several key algorithms implemented over the last decade with these gates and give a detailed description of Grover's quantum database search implemented with two trapped ion qubits.

International Nuclear Information System (INIS)

We study a quantum computing system using microwave photons in transmission line resonators on a superconducting chip as qubits. We show that linear optics and other controls necessary for quantum computing can be implemented by coupling to Josephson devices on the same chip. By taking advantage of the strong nonlinearities in Josephson junctions, photonic qubit interactions can be realized. We analyze the gate error rate to demonstrate that our scheme is realistic even for Josephson devices with limited decoherence times. As a conceptually innovative solution based on existing technologies, our scheme provides an integrated and scalable approach to the next key milestone for photonic qubit quantum computing.

Energy Technology Data Exchange (ETDEWEB)

In this talk, we explore the feasibility of quantum computation using continuous-variable systems by means of local measurements only. In the first part of the talk, we will identify crucial limitations that arise when starting from Gaussian cluster states. This is done by resorting to a Gaussian projected entangled pair picture as well as to notions of continuous-variable quantum repeater networks. In the second part, we look at instances in which these limitations can be overcome, and how suitable encodings of qubits in oscillators and feasible non-Gaussian resource states give rise to universal schemes for quantum computing.

Science.gov (United States)

In this paper, we proposed a novel quantum secure direct communication scheme with one-time pad in stabilizer formalism. Based on the reuse of qubit sequence, an efficient secure communication of secret messages without first producing a shared secret key can be achieved. One hence may find that the amount of private key needed for quantum communication is smaller than that in the general case. Therefore, the present protocol which is feasible with the present-day techniques may be applied to quantum communication with short-length encoding.

CERN Document Server

We study the all-optical time-control of the strong coupling between a single cascade three-level quantum emitter and a microcavity. We find that only specific arrival-times of the control pulses succeed in switching-off the Rabi oscillations. Depending on the arrival times of control pulses, a variety of exotic non-adiabatic cavity quantum electrodynamics effects can be observed. We show that only control pulses with specific arrival times are able to suddenly switch-off and -on first-order coherence of cavity photons, without affecting their strong coupling population dynamics. Such behavior may be understood as a manifestation of quantum complementarity.

International Nuclear Information System (INIS)

The Advanced Test Reactor (ATR) at the Idaho National Engineering Laboratory was designed with some passive safety response attributes which contribute to the safety of the facility. The three passive safety attributes being evaluated in the paper are: 1) In-core and in-vessel natural convection cooling, 2) a passive heat sink capability of the ATR primary coolant system (PCS) for the transfer of decay power from the uninsulated piping to the confinement, and 3) gravity feed of emergency coolant makeup. The safety significance of the ATR passive safety response attributes is that the reactor can passively respond to most transients, given a reactor scram, to provide adequate decay power removal and a significant time for operator action should the normal active heat removal systems and their backup systems both fail. The ATR Interim Level 1 Probabilistic Risk Assessment (PRA) models and results were used to evaluate the ...

Energy Technology Data Exchange (ETDEWEB)

A 308-size hybrid ball bearing, with ceramic balls and steel rings, was tested using a diester oil and gas turbine fuel as lubricants at several speeds and loads. Heat generation data from this test work was then correlated with the heat generation model from a widely used computer code. The ability of this hybrid split inner ring bearing design to endure thrust reversals, which are expected in many turbine applications, was demonstrated. Finally, the bearing was successfully endurance tested in JP-10 fuel for 25 hours at 7560 N axial load and 36,000 rpm. This work has successfully demonstrated the technology necessary to use fuel-lubricated hybrid bearings in limited-life gas turbine engine applications such as missiles, drones, and other unmanned air vehicles (UAVs). In addition, it has provided guidance for use in designing such bearing systems. As a result, the benefits of removing the conventional oil lubricant system, ...

Energy Technology Data Exchange (ETDEWEB)

A new performance model of the externally fired combined cycle (EFCC) is implemented in ASPEN (Advanced System for Process ENgineering), a chemical process simulator. The model accounts for interactions within and between approximately a dozen major process areas. The new model is applied to case studies to evaluate the sensitivity of process performance to the ranges of uncertainty in key model inputs such as heat losses, carbon conversion, and air leakage rates, and to illustrate how alternative designs, including steam injection and flue gas desulfurization (FGD), can affect plant thermal efficiency and net power output. The model results suggest that careful attention to the design of the FGD system is needed, especially with respect to reheat, and that steam injection may offer cost savings associated with reducing the size of the steam turbine with little or no penalty on plant output or plant efficiency. Uncertainties in the slagging ...

Energy Technology Data Exchange (ETDEWEB)

In order to investigate the effect of humidity on laminar burning velocity(S), the effect of humidity on the combustion reaction and radiation intensity was studied, taking account of dilution gases such as CO/sub 2/ and Ar which has the approximately identical characteristics to exhaust gas circulation(EGR) gas used to prevent NOx discharge from engines. According to the heat reaction theory, mean specific heat(C) of mixture, mean molecular weight(M) and adiabatic flame temperature(T) etc. were said to affect S but from experimental results, the effect of M and C could be ignored, compared with the effect of T. The relationship between S and H/sub 2/O, Ar of CO/sub 2/% in mixture of diluted gases was clarified. The effect of H/sub 2/O on S was mainly caused by changes of T. The effect of radical C/sub 2/, CH and OH on radiation intensity was similar to that of H/sub 2/O and Ar and the effect of H/sub 2/O on combustion was ...

International Nuclear Information System (INIS)

A personal computer based single specimen unloading technique has been demonstrated using a nuclear grade pressure vessel material, A533B Class I steel, and an #alpha#-#beta# titanium alloy, CORONA-5. Experimental parameters investigated in the case of steel include the effect of test temperature, loading rate and neutron irradiation. Results revealed the effect of dynamic strain aging (DSA) as a drop in the critical crack initiation fracture toughness (Jsub(q)); the minimum in Jsub(q) shifts to higher temperatures at higher test speeds as predicted from DSA models. In CORONA-5, the effects of microstructure and heat treatment for two different sizes of equiaxed #alpha# morphology in a #beta#-matrix heat treated to different yield strengths were investigated. It is found that the observed higher values of Jsub(q) and tearing modulus result from a greater tortuosity of the crack path and ease of crack blunting. The largest increase in Jsub(q) ...

International Nuclear Information System (INIS)

The propriety of the cosmic no-hair conjecture to the Bianchi-type-IX spacetime is discussed from a quantum cosmological point of view. It is shown that most, but not all, classical universes which are created quantum cosmologically are inflationary. The probability of inflation among such universes is also discussed.

CERN Document Server

We obtain a simple derivation of the optimal quantum state estimation of a two-level system using the no-signaling principle. In particular, we show that the no-signaling principle determines the unique form of the guessing probability, independently to a given figure of merit such as the fidelity or the information gain. This proves that optimal measurements for a two-level quantum system is the same for almost all figures of merit.

CERN Document Server

Two-dimensional generalization of the original peak finding algorithm suggested earlier is given. The ideology of the algorithm emerged from the well known quantum mechanical tunneling property which enables small bodies to penetrate through narrow potential barriers. We further merge this ``quantum'' ideology with the philosophy of Particle Swarm Optimization to get the global optimization algorithm which can be called Quantum Swarm Optimization. The functionality of the newborn algorithm is tested on some benchmark optimization problems.

CERN Document Server

A consistent combination of quantum geometry effects rules out a large class of models of loop quantum cosmology and their critical densities as they have been used in the recent literature. In particular, the critical density at which an isotropic universe filled with a free, massless scalar field would bounce must be well below the Planck density. In the presence of anisotropy, no model of the Schwarzschild black hole interior analyzed so far is consistent.

Energy Technology Data Exchange (ETDEWEB)

Implementation of quantum logical gates for multilevel systems is demonstrated through decoherence control under the quantum adiabatic method using simple phase modulated laser pulses. We make use of selective population inversion and Hamiltonian evolution with time to achieve such goals robustly instead of the standard unitary transformation language. (letter to the editor)

Science.gov (United States)

... and Engineering (NISE), Instructional Materials Development in Nanoscale Science and Engineering ... & Physical Sciences, Division of Materials Research, 1065 N, telephone: (703) 292-4937, email: lhess ...

Science.gov (United States)

...QUALIFICATION AND CERTIFICATION OF LOCOMOTIVE ENGINEERS Implementation of the Certification...operations and certifies locomotive engineers from a different railroad...designated supervisor of locomotive engineers or a certified train...

Energy Technology Data Exchange (ETDEWEB)

This report documents the Proceedings of the 1997 Oil Heat Technology Conference and Workshop, held on April 3--4 at Brookhaven National Laboratory (BNL), and sponsored by the US Department of Energy--Office of Building Technologies, State and Community programs (DOE-BTS), in cooperation with the Petroleum Marketers Association of America (PMAA). This Conference is a key technology transfer activity supported by the ongoing Combustion Equipment Technology (Oil-Heat R and D) program at BNL, and is aimed at providing a forum for the exchange of information among international researchers, engineers, manufacturers, and marketers of oil-fired space-conditioning equipment. The objectives of the Conference were to: identify and evaluate the state-of-the-art and recommend new initiatives for higher efficiency, a cleaner environment, and to satisfy consumer needs cost-effectively, reliably, and safely: and foster cooperation among ...

CERN Document Server

We present a strong-weak coupling duality for quantum mechanical potentials. Similarly to what happens in quantum field theory, it relates two problems with inverse couplings, leading to a mapping of the strong coupling regime into the weak one, giving information from the nonperturbative region of the parameters space. It can be used to solve exactly power-type potentials and to extract deep information about the energy spectra of polynomial ones. We present a strong-weak coupling duality for quantum mechanical potentials. Similarly to what happens in quantum field theory, it relates two problems with inverse couplings, leading to a mapping of the strong coupling regime into the weak one, giving information from the nonperturbative region of the parameters space. It can be used to solve exactly power-type potentials and to extract deep information about the energy spectra of polynomial ones.

CERN Document Server

This Chapter develops a realist information-theoretic interpretation of the nonclassical features of quantum probabilities. On this view, what is fundamental in the transition from classical to quantum physics is the recognition that \\emph{information in the physical sense has new structural features}, just as the transition from classical to relativistic physics rests on the recognition that space-time is structurally different than we thought. Hilbert space, the event space of quantum systems, is interpreted as a kinematic (i.e., pre-dynamic) framework for an indeterministic physics, in the sense that the geometric structure of Hilbert space imposes objective probabilistic or information-theoretic constraints on correlations between events, just as the geometric structure of Minkowski space in special relativity imposes spatio-temporal kinematic constraints on events. The interpretation of quantum ...

CERN Document Server

Bargmann's superselection rule, which forbids the existence of superpositions of states with different mass and, therefore, implies the impossibility of describing unstable particles in non-relativistic quantum mechanics, arises as a consequence of demanding Galilean covariance of Schr\\"odinger's equation. However, the usual Galilean transformations inadequately describe the symmetries of non-relativistic quantum mechanics since they fail to take into account relativistic time contraction effects which can produce non-relativistic phases in the wavefunction. In this paper we describe the incompatibility between Bargmann's rule and Lorentz transformations in the low-velocities limit, we analyze its classical origin and we show that the Extended Galilei group characterizes better the symmetries of the theory. Furthermore, we claim that a proper description of non-relativistic quantum mechanics requires a modification of the ...

Energy Technology Data Exchange (ETDEWEB)

This handbook provides the necessary tools for the engineer to design forced-cooled HPOF pipe-type cable systems. It represents the final objective of a major project which included an extensive research program at the Waltz Mill Forced-Cooling Test Facility. The formulas and procedures presented in this handbook are consistent with the results of this program as well as other full-scale and model investigations. Introductory material, including historical information, general design concepts and basic heat transfer and fluid dynamics theory is given for those who are unfamiliar with the fundamental principles of forced-cooling. The nucleus of the handbook consists of equations and calculating procedures for determining forced-cooled parameters and thermal/hydraulic performance levels. Both simple and sophisticated procedures have been provided, with the more complex procedures treating such areas as the thermal interaction between cable pipes ...

CERN Document Server

Classical control theory has played a major role in the development of present-day technologies. Likewise, recently developed quantum optimal control methods can be applied to emerging quantum technologies, e.g. quantum information processing -- until now, at the level of a few qubits. However, such methods encounter severe limits when applied to many-body quantum systems: due to the complexity of simulating the latter, existing quantum control algorithms (requiring many iterations to converge) usually fail to yield a desired final state within an acceptable computational time. In contrast, we present here a strategy for controlling a vast range of non-integrable one-dimensional systems that is efficiently applicable to quantum many-body systems, as it can be merged with state-of-the-art tensor network simulation methods like the Density Matrix Renormalization ...

Science.gov (United States)

PMID:21807581

Energy Technology Data Exchange (ETDEWEB)

To utilize ethanol from agricultural residue as a fuel in diesel engines, a dual-fuel engine was developed. The engine, which was equipped with a system to electrically control diesel and alcohol flow rates, met basic requirements of a tractor engine, including engine speed control and setting of the torque curve. However, engine knock due to alcohol was a significant drawback. A diesel injection pump with a timing and flow rate control system was adapted, and the effect of injection timing on combustion and performance was investigated. It was observed that the timing control was effective in reducing engine knock caused by rapid alcohol combustion. (author)

Science.gov (United States)

... management. 5.3 Decreased Emissions Changes in engine emission regulations are driving engine technology development. A ...

Science.gov (United States)

A compact heat exchanger pedestal array for augmenting heat transfer in a machine is disclosed. The compact heat exchanger pedestal array includes a wall having first and second surfaces. The first surface faces a heated flow path and the second surface p...

Energy Technology Data Exchange (ETDEWEB)

The construction of networks consisting of optically interconnected processing units is a promising way to scale up quantum information processing systems. To store quantum information, single trapped atoms are among the most proven candidates. By placing them in high finesse optical resonators, a bidirectional information exchange between the atoms and photons becomes possible with, in principle, unit efficiency. Such an interface between stationary and ying qubits constitutes a possible node of a future quantum network. The results presented in this thesis demonstrate the prospects of a quantum interface consisting of a single atom trapped within the mode of a high-finesse optical cavity. In a two-step process, we distribute entanglement between the stored atom and two subsequently emitted single photons. The long atom trapping times achieved in the system together with the high photon collection ...

Science.gov (United States)

Not Available

Energy Technology Data Exchange (ETDEWEB)

Two natural gas/diesel dual fuel conversion systems for the Detroit Diesel 6V-71 transit bus engine were described. The basic concept of a dual fuel engine was to operate a diesel engine with both liquid fuel injection and a lean premixed gas mixture. The engine achieved high efficiency due to the high compression ratio typical of the diesel engine. Test results were obtained using three different calibrations on one engine. The objectives were to match existing engine performance with improved emissions and better overall fuel economics. Results showed that overall, engine conversion has both economic and emissions advantages over a straight diesel engine. However, the durability and in-use applicability of the system remains to be demonstrated with an in-bus demonstration project.. 3 tabs., 4 figs.

Energy Technology Data Exchange (ETDEWEB)

The canonical quantum theory of gravity-quantum geometrodynamics (QG)-is applied to the homogeneous Bianchi type IX cosmological model. As a result, a framework for the quantum theory of homogeneous cosmologies is developed. We show that the theory is internally consistent and prove that it possesses the correct classical limit (the theory of general relativity). To emphasize the special role that the constraints play in this new theory, we compare it to the traditional ADM square-root and Wheeler-DeWitt quantization schemes. We show that, unlike traditional approaches, QG leads to a well-defined Schroedinger equation for the wavefunction of the universe that is inherently coupled to the expectation value of the constraint equations. This coupling to the constraints is responsible for the appearance of a coherent spacetime picture. Thus, the physical meaning of the constraints of the theory is quite different from ...

CERN Document Server

We consider the role of quantum effects in the transfer of hyrogen-like species in enzyme-catalysed reactions. This study is stimulated by claims that the observed magnitude and temperature dependence of kinetic isotope effects imply that quantum tunneling below the energy barrier associated with the transition state significantly enhances the reaction rate in many enzymes. We use a path integral approach which provides a general framework to understand tunneling in a quantum system which interacts with an environment at non-zero temperature. Here the quantum system is the active site of the enzyme and the environment is the surrounding protein and water. Tunneling well below the barrier only occurs for temperatures less than a temperature $T_0$ which is determined by the curvature of potential energy surface near the top of the barrier. We argue that for most enzymes this temperature is less than room ...

CERN Document Server

English abstract: In the "Intuitive Quantum Physics" course, we use graphical interpretations of mathematical equations and qualitative reasoning to develop and teach a simplified model of quantum physics. Our course contains three units: Wave physics, Development of a conceptual toolbox, and quantum physics. It also contains three key themes: wave-particle duality, the Schroedinger equation, and tunneling of quantum particles. Students learn most new material in lab-tutorials in which students work in small groups (3 to 3 people) on specially designed worksheets. Lecture reinforces the lab-tutorial content and focuses more on issues about the nature of science. Data show that students are able to learn some of the most difficult concepts in the course, and also that students learn to believe that there is a conceptually accessible structure to the physics in the course. German abstract: Im Kurs ...

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... Alexandria Engineering Journal- The Alexandria Engineering Journal (AEJ) is an international journal devoted to publishing high quality papers in the field..... Alexandria Engineering Journal - Elsevier Home Products User Resources About Us Support & Contact Elsevier Websites Advanced Product Search Browse ...Journals Alexandria Engineering Journal Alexandria Engineering Journal Production and Hosting by Elsevier B.V. on behalf of Faculty of Engineering, Alexandria University ...Indexing Editors Reviewers Log in as Reviewer Advertisers/Sponsors Societies ISSN: 1110-0168 Imprint: ALEXANDRIA UNIVERSITY Actions Submit Article Order Journal ...

CERN Document Server

Using some modification of the standard fermion technique we derive factorized formula for spin operator matrix elements (form-factors) between general eigenstates of the Hamiltonian of quantum Ising chain in a transverse field of finite length. The derivation is based on the approach recently used to derive factorized formula for Z_N-spin operator matrix elements between ground eigenstates of the Hamiltonian of the Z_N-symmetric superintegrable chiral Potts quantum chain. The obtained factorized formulas for the matrix elements of Ising chain coincide with the corresponding expressions obtained by the Separation of Variables Method.

CERN Document Server

We present investigations of the potential between static charges from a simulation of quantum gravity coupled to an SU(2) gauge field on 6^{3}\\times 4 and 8^{3}\\times 4 simplicial lattices. In the well-defined phase of the gravity sector where geometrical expectation values are stable, we study the correlations of Polyakov loops and extract the corresponding potentials between a source and sink separated by a distance R. In the confined phase, the potential has a linear form while in the deconfined phase, a screened Coulombic behavior is found. Our results indicate that quantum gravitational effects do not destroy confinement due to non-abelian gauge fields.

International Nuclear Information System (INIS)

The theory of spontaneous decay is studied using both quantum electrodynamics (QED) and semiclassical theories of radiation. There are qualitative differences between the theories in the prediction of interference phenomena. In QED, systems which were excited with pulsed laser light do not exhibit quantum interference effects associated with lower state splittings. On the other hand, semiclassical treatments of spontaneous decay do indicate the existence of interference effects not present in QED. In addition to this, differences are found between the predictions of fluorescence intensity in the presence of lower-state level crossings under continuous excitation. (U.S.).

CERN Document Server

In the inflationary scenario of loop quantum cosmology (LQC) in the presence of inverse-volume corrections, we give analytic formulas for the power spectra of scalar and tensor perturbations convenient to confront with observations. Since inverse-volume corrections can provide strong contributions to the running spectral indices, inclusion of terms higher than the second-order runnings in the power spectra is crucially important. Using the recent data of cosmic microwave background (CMB) and other cosmological experiments, we place bounds on the quantum corrections for a quadratic inflaton potential.

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It is proved the mathematical theorem, that the wave function describes the statistical ensemble of particles, but not a single particle. Supposition, that the wave function describes a single particle appears to be incompatible with formalism of quantum mechanics. One discusses the reasons, why this very simple statement has not been proved mathematically for many years. The reason lies in application of the trial and error methods for construction of the quantum mechanics. Application of this method as the main tool of investigation during eighty years generated "fitting mentality" of all microwold researchers.

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An effective formalism for quantum constrained systems is presented which allows manageable derivations of solutions and observables, including a treatment of physical reality conditions without requiring full knowledge of the physical inner product. Instead of a state equation from a constraint operator, an infinite system of constraint functions on the quantum phase space of expectation values and moments of states is used. The examples of linear constraints as well as the free non-relativistic particle in parameterized form illustrate how standard problems of constrained systems can be dealt with in this framework.