CERN Document Server

Lithography Production Techniques for next Generations of Microelectronics

Energy Technology Data Exchange (ETDEWEB)

Since 1979, scientists and engineers at the Los Alamos National Laboratory have designed, constructed, and operated a radio-frequency (RF) linac free-electron laser (FEL) at wavelengths from 9 to 45 /mu/m. Coupled with success of other research centers investigating wavelengths from the visible to far-infrared, Los Alamos is now proposing a vacuum-ultraviolet and soft x-ray (referred to henceforth as extreme ultraviolet, (XUV)) FEL oscillator/Self-Amplified Spontaneous Emission amplifier with beam energies ranging from 100 MeV to 1 GeV. This paper will focus on the first milestone of the proposed Los Alamos XUV project, i.e., a 250-MeV linac with approximately 50 mA of average current, producing photons with wavelengths below 1000 /angstrom/. 3 refs., 3 figs.

International Nuclear Information System (INIS)

Our institute has been investigating laser-produced tin, lithium and xenon plasma for extreme ultraviolet (EUV) light source of EUV lithography system, and found the highest conversion efficiency of 3% at 13.5 nm in 2% bandwidth. In the present paper, we introduce fabrication methods of density-controlled tin targets to generate relatively monochromatic EUV, and higher conversion efficiency than bulk tin. The first method is the nano-template method, where liquid tin solution was immersed into a polymer film with monodispersed size nano-particle. The density can be controlled by tin concentration of the solution. The target can be classified into mass-limited target. We have shown a tendency of monochromatic EUV emission around 13.5 nm with decreasing of tin density. The intensity was higher than tin foil with bulk density. The tendency has a merit to mitigate heat effect of the first EUV mirror. The fabrication method has another merit to ...

Science.gov (United States)

... Corporate Author : MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB. Personal Author(s) : Rothschild, M. ; Ehrlich, DJ. ...

Energy Technology Data Exchange (ETDEWEB)

The motivation of this work is to develop high reflectance normal-incidence multilayer mirrors in the 8-12 nm wavelength region for applications in astronomy and extreme ultraviolet lithography. To achieve this goal, Mo/Sr and Mo/Y multilayers were studied. These multilayers were deposited with a UHV magnetron sputtering system and their reflectances were measured with synchrotron radiation. High normal-incidence reflectances of 23% at 8.8 nm, 40.8% at 9.4 nm, and 48.3% at 10.5 nm were achieved. However, the reflectance of Mo/Sr multilayers decreased rapidly after exposure to air. Attempts to use thin layers of carbon to passivate the surface of Mo/Sr multilayers were unsuccessful. Experimental results on the refractive index {tilde n} = 1-{delta} + i{beta} of yttrium and molybdenum in the 50-1300 eV energy region are reported in this work. This is the first time ever that values on the refractive index of yttrium are measured in this energy ...

Science.gov (United States)

Generally the photonic band gap (PBG) is a multi-variable function of several parameters related to the shape and size of the dielectric columns of photonic crystals (PhCs), and a time-consuming step-by-step scanning process for each parameter has to be used to find their best combination yielding maximum PBG. In this letter, the widely used Nelder-Mead simplex algorithm is introduced to optimize these parameters simultaneously to find a larger PBG for a new kind of two-dimensional (2D) hexagonal GaAs-Air PhC. This structure can be conveniently produced by the single-exposure holographic lithography, and the specific holographic design is also systematically investigated. This study reveals that the band gaps of PhCs made by holographic lithography may be widened by introducing irregularity of the columns and lowering the symmetry of the structure.

Science.gov (United States)

UV dwarf star evolution, using central and gap star models emphasizing photoneutrino emission

Energy Technology Data Exchange (ETDEWEB)

In this study, the effects of 325nm wavelength ultraviolet light irradiation on pitting corrosion behavior of type 340 stainless steel in a neutral chloride solution are studied. Further, the change of passive film with the light irradiation is analyzed using x-ray photoelectron spectroscopy. The mains results obtained therefrom are stated below. Pitting potential can be shifted in noble direction by the ultraviolet light irradiation. The effect of ultraviolet light irradiation is ore prominent in the pitting corrosion process than that in the passive film formation. The result of the analysis in terms of the birth and death stochastic probability process shows that pitting corrosion rate is decreased remarkably by the ultraviolet light irradiation at the formation of passive film, while the repassivation is slightly expedited by the ultraviolet light irradiation. On the other hand, ...

Energy Technology Data Exchange (ETDEWEB)

This dissertation deals with both the theoretical and the technological aspects of monolithic tunable lasers, and the experimental techniques for opto-electronic integration. In the theoretical part, the principles and limitations of wavelength tuning and spectral linewidth reduction in monolithic semiconductor lasers are described, with coupled distributed feedback-Fabry Perot (DFB-FP) lasers and long DFB lasers as examples. Stepwise tuning of wavelength over tens of nanometers and continuous tuning over the range of a mode spacing are shown to be possible. Spatial hole burning is found to affect the spectral linewidth of lasers involving strong active gratings. On the technological side, one of the major issues is the fabrication of flexible gratings. Direct-writing techniques, such as focused ion beam (FIB) implantation and e-beam lithography, provide the resolution, flexibility and accuracy that conventional holographic lithography lacks. ...

KoreaScience (Korea)

Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Successful interface engineering requires compositional and electronic material characterization as a prerequisite for understanding and intentionally generating interfaces in photovoltaic devices. The paper gives an overview with several examples, all referring to Cu(In,Ga)(S,Se){sub 2} ('CIGSSe')-based solar cells, with an emphasis on characterization using highly specialized methods, such as elastic recoil detection analysis, X-ray emission spectroscopy and photoelectron spectroscopy using synchrotron and ultraviolet light for excitation, inverse photoemission spectroscopy and Kelvin probe force microscopy. First, the determination of the depth profile of the band gap energy E{sub g} in the absorber layer is demonstrated. The modification of E{sub g} towards both interfaces is discussed in terms of beneficial electronic effects. Next, the interface between absorber and buffer layers with alternative and promising non-toxic ...

Energy Technology Data Exchange (ETDEWEB)

In order to judge the potential fluorescent lamp applications of various low-pressure positive column discharges it is necessary to measure the absolute power emitted in the ultraviolet region of the spectrum. For rare-gas discharges the principle emission occurs in the vacuum ultraviolet so that it is difficult to measure the radiant emittance (power per unit area) of the resonance radiation by standard methods. Two independent techniques are discussed for measuring the radiant emittance of positive column discharges in the vacuum ultraviolet. These techniques are used to study xenon positive column discharges at the resonance wavelength of 147 nm. The first method relies on the measurement of the resonance level density by absorption techniques. The effective decay rate of the resonance level is then determined by the simulation of resonance radiation transport. These two quantities are combined to yield the radiant ...

Science.gov (United States)

... The addition of 0.5 pphr of fine thermal carbon black to the polymers gave good resistance to 500 hours of ultraviolet (UV) xposure in a Weather ...

British Library Electronic Table of Contents (United Kingdom)

Properties of photoconductive ultraviolet detectors fabricated on ZnO films were presented. Highly c-axis oriented ZnO films were grown on glass substrates by pulsed laser deposition. Ultraviolet photodetectors were fabricated based on metal-semiconductor-metal planar structures. The photoresponsivity and the quantum efficiency are much higher in the ultraviolet range than in the visible range, and the peak values are around 360nm. Photocurrent transients show that the detector has a large photocurrent with the peak value of 2.8mA, and a slow photoresponse with a rise time of 5min and a decay time of 7min. The response curve of the detector is fitted well with exponential curve. The large photocurrent should result from the both effects of the accumulation of conduction electrons and the d...

International Nuclear Information System (INIS)

High power and particle deposition on target materials are encountered in many applications including magnetic and inertial fusion devices, nuclear and high energy physics applications, and laser and discharge produced plasma devices. Surface and structural damage to plasma-facing components due to the frequent loss of plasma confinement remains a serious problem for the Tokamak reactor concept. The deposited plasma energy causes significant surface erosion, possible structural failure, and frequent plasma contamination.

Energy Technology Data Exchange (ETDEWEB)

A rapid and accurate method for the direct simultaneous determination of nitrate and nitrite is proposed. The method is applied to the determination of nitrate and nitrite in rainwater and wastewater without preliminary separation. The determinations are performed by a CPA matrix method with ultraviolet spectrophotometric detection. The results obtained are in agreement with those obtained by conventional methods for the determination of nitrate and nitrite.

International Nuclear Information System (INIS)

Spontaneous and ultraviolet-induced changeabilities of wine yeasts from the killer state to sensitive one have been studied. Observed often spontaneous changes of killer and neutral phenotypes under laboratory store conditions as well as high mutation frequency of genetic elements responsible for the killer indication on ultraviolet irradiation testify that often encounterability in nature and in the production of sensitive yeasts is attributed to high frequency of mutation changes of the killer and neutral phenotypes to the sensitive state.

Energy Technology Data Exchange (ETDEWEB)

Tetracycline is an antibiotic that absorbs ultraviolet light at 355 nm and preferentially binds to atherosclerotic plaque both in vitro and in vivo. Tetracycline-treated human cadaveric aorta was compared with untreated aorta using several techniques: absorptive spectrophotometry; and tissue uptake of radiolabeled tetracycline, which showed 4-fold greater uptake by atheroma than by normal vessel. In addition, intravenous tetracycline administered to patients undergoing vascular surgery demonstrated characteristic fluorescence in surgically excised diseased arteries. Because of tetracycline's unique properties, the authors exposed tetracycline-treated and untreated aorta to ultraviolet laser radiation at a wavelength of 355 nm. They found enhanced ablation of tetracycline-treated atheroma compared with untreated atheroma. The plaque ablation caused by ultraviolet laser radiation was twice as extensive in ...

Index Scriptorium Estoniae

Heliplaadist

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

International Nuclear Information System (INIS)

I report on some recent work done in collaboration with E. de Rafael on the connection between ultraviolet renormalons in QCD and Nambu-Jona-Lasinio-like Lagrangians as its effective description at low energies. (orig.)

UK PubMed Central (United Kingdom)

Sunbed use is associated with increased risk of melanoma. Younger people might be more susceptible to the carcinogenic effects of ultraviolet radiation. We investigated the association between...Full Text Available

UK PubMed Central (United Kingdom)

Amide n –π^* and π-π^* excitations around 200 nm are prominent spectroscopic...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Properties of photoconductive ultraviolet detectors fabricated on ZnO films were presented. Highly c-axis oriented ZnO films were grown on glass substrates by pulsed laser deposition. Ultraviolet photodetectors were fabricated based on metal-semiconductor-metal planar structures. The photoresponsivity and the quantum efficiency are much higher in the ultraviolet range than in the visible range, and the peak values are around 360 nm. Photocurrent transients show that the detector has a large photocurrent with the peak value of 2.8 mA, and a slow photoresponse with a rise time of 5 min and a decay time of 7 min. The response curve of the detector is fitted well with exponential curve. The large photocurrent should result from the both effects of the accumulation of conduction electrons and the decrease of the barrier height between crystallites. The relaxation time constant {tau} obtained from the curve fitting represents the ...

UK PubMed Central (United Kingdom)

BackgroundChildhood is a high risk time for ultraviolet induced skin damage as this age group has more time and opportunity to be outdoors in the sun. Children in Africa with the...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundPreclinical studies indicate that the enzyme cyclooxygenase 2 plays an important role in ultraviolet-induced skin cancers. We evaluated the efficacy and safety of celecoxib,...Full Text Available

International Nuclear Information System (INIS)

20 nm thick permalloy elements, with dimensions of 500 x 500 nm"2 and 1000 x 200 nm"2, have been fabricated on 50 nm thick silicon nitride substrate by milling using a focussed ion beam (FIB) microscope. The dose of ion beam used for the milling was varied in order to achieve the best definition for the milled areas. The FIB milled elements were characterised physically by atomic force microscopy (AFM) and bright field transmission electron microscopy (TEM) and magnetically by Fresnel imaging on a TEM modified for magnetic imaging. The FIB milled elements were found to have a more irregular edge and lower magnetic fields for events such as vortex annihilation when compared to elements of the same dimensions fabricated by conventional electron beam microscopy (EBL).

International Nuclear Information System (INIS)

We report on the improvement of Critical Dimension (CD) linearity on a photomask by applying the concept of process proximity correction to a laser lithographic process used for fabrication of photomasks. Rule-based Laser Process proximity Correction (LPC) was performed using an automated optical proximity correction tool and we obtained dramatic improvement of CD linearity on a photomask. A study on model-based LPC was executed using a two-Gaussian kernel function and we extracted model parameters for the laser lithographic process by fitting the model-predicted CD linearity data with measured ones. Model-predicted bias values of isolated space (I/S), Arrayed Contact (A/C) and Isolated Contact (I/C) were in good agreement with those obtained by the nonlinear curve-fitting method used for the rule-based LPC.

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...

Science.gov (United States)

PMID:21807581

Energy Technology Data Exchange (ETDEWEB)

Two sources of ultraviolet (UV) radiation with peak wavelengths in the UV-C or UV-B ranges were compared for their ability to sterilize contact lenses infected with Pseudomonas aeruginosa, Streptococcus pneumoniae, Acanthamoeba castellani, Candida albicans, and Aspergillus niger. Also examined was the effect of prolonged UV light exposure on soft and rigid gas permeable (RGP) contact lenses. The UV-C lamp (253.7 nm, 250 mW/cm2 at 1 cm) was germicidal for all organisms within 20 minutes but caused destruction of the soft lens polymers within 6 hours of cumulative exposure. UV-C caused damage to RGP lenses in less than 100 hours. The UV-B lamp (290-310 nm, 500 mW/cm2 at 1 cm) was germicidal for all organisms tested (except Aspergillus) with a 180-minute exposure and caused less severe changes in the soft lens polymers than did the UV-C lamp, although cumulative exposure of 300 hours did substantially weaken the soft lens material. RGP materials were minimally ...

CERN Document Server

We present the results of a search for Extreme Ultraviolet emission in A4059, a cluster with an X-ray emitting cluster gas. Our analysis of Extreme Ultraviolet Explorer (EUVE) Deep Survey observations of this cluster shows that it is associated with diffuse EUV emission. Outside the central 2 arcmin radius the entire EUV emission detected is explained by the low energy tail of the X-ray emitting gas. Within the central 2 arcmin region of the cluster we find a deficit of EUV emission compared to that expected from the X-ray gas. This flux deficit is discussed in the context of the cluster's cooling flow. The results derived for A4059 are compared to EUVE results obtained for other clusters such as Coma, Virgo, A1795, and A2199. As part of the study we have carried out a detailed investigation of the stability of the EUVE Deep Survey detector background. Based on long integrations of blank sky over 27 months we disprove claims of substantial time ...

Science.gov (United States)

This report covers the initial DARPA DTN Phase 3 activities as JPL provided Core Engineering Support

British Library Electronic Table of Contents (United Kingdom)

Purpose Ultraviolet-B (UV-B) radiation can cause phototoxic macular injuries in young people who have been sunbathing but not sungazing and in welders. Welders have a reportedly increased risk of uveal melanoma. We analyze phakic and pseudophakic risks for solar and welding arc UV-B exposure. Design Optical radiation measurement, analysis, and perspective. Methods Spectral transmittances were measured for UV-transmitting, UV-blocking, and blue-blocking intraocular lenses (IOLs). The photoprotective performances of crystalline and intraocular lenses were analyzed using relevant epidemiologic and laboratory data and action spectra for acute retinal phototoxicity and melanoma photocarcinogenesis. Results Crystalline lens UV-B retinal protection is deficient in children and young adults, incre...

Energy Technology Data Exchange (ETDEWEB)

Thin film ultraviolet detectors based on hydrogenated amorphous silicon alloys are realized with different diode structures (PIN, NIP, PN, and NP). The PIN and NIP detectors exhibit higher sensitivity in the ultraviolet spectrum and a significant lower dark current in comparison to the PN or NP structures. The best detector performance was achieved with a 33 nm thick PIN diode. This detector shows a maximum of quantum efficiency of 36.3% at a wavelength of 310 nm. By varying the thickness of the semi-transparent Ag front contact the selectivity of the detectors with the quantum efficiency peak at 320 nm can be adjusted. Thus, the spectral sensitivity of the detector shifts from a broad UV to a selective UV-B spectrum. (orig.)

British Library Electronic Table of Contents (United Kingdom)

With conventional heating process, ultraviolet (UV) illumination, and microwave irradiation, we have successfully synthesized UV curable encapsulating adhesives with excellent gas barrier capabilities, good adhesive strength, moderate hardness, and high refractive indices. The experimental results manifest that the physical properties of lab-made encapsulating adhesives are highly dependent on their chemical structures and synthetic procedure. We also discover that the encapsulating adhesive prepared by microwave irradiation (i.e. encapsulating adhesive VI-MW) exhibits better adhesive strength and higher gas resistance than those prepared by conventional heating process and UV illumination. Furthermore, encapsulating adhesive VI-MW has also been applied for the package of organic light emi...

CERN Document Server

The Warm-Hot Intergalactic Medium (WHIM) arises from shock-heated gas collapsing in large-scale filaments and probably harbours a substantial fraction of the baryons in the local Universe. Absorption-line measurements in the ultraviolet (UV) and in the X-ray band currently represent the best method to study the WHIM at low redshifts. We here describe the physical properties of the WHIM and the concepts behind WHIM absorption line measurements of H I and high ions such as O VI, O VII, and O VIII in the far-ultraviolet and X-ray band. We review results of recent WHIM absorption line studies carried out with UV and X-ray satellites such as FUSE, HST, Chandra, and XMM-Newton and discuss their implications for our knowledge of the WHIM.

Energy Technology Data Exchange (ETDEWEB)

A composition and method for encapsulating a photovoltaic device which minimizes discoloration of the encapsulant. The composition includes an ethylene-vinyl acetate encapsulant, a curing agent, an optional ultraviolet light stabilizer, and/or an optional antioxidant. The curing agent is preferably 1,1-di-(t-butylperoxy)-3,3,5-trimethylcyclohexane; the ultraviolet light stabilizer is bis-(N-octyloxy-tetramethyl) piperidinyl sebacate and the antioxidant is selected from the group consisting of tris (2,4-di-tert-butylphenyl) phosphite, tetrakis methylene (3,5-di-tert-butyl-4-hydroxyhydrocinnamate) methane, octadecyl 3,5-di-tert-butyl-4-hydroxyhydrocinnamate, and 2,2'-ethylidene bis(4,6-di-t-butylphenyl) fluorophosponite. The composition is applied to a solar cell then cured. The cured product contains a minimal concentration of curing-generated chromophores and resists UV-induced degradation.

International Nuclear Information System (INIS)

Using the advantage that the projected range of ions in matter is sharply limited, a new technique for the production of three-dimensional microstructures has been developed. Based on the P-LIGA technique (Proton-Lithographie, Galvanoformung, Abformung) this process allows the generation of structures with surfaces of almost any shape having a root mean square roughness of about #lambda#/50 for visible light wavelengths. An ion beam with diameters between 2 and 50 #mu#m is directly writing the structures and the shape is varied by geometrical manipulation of the sample in three axes during the exposure. Practically, structures have been written using protons with an energy of 1.8 MeV in a provisional experimental setup with beam diameters of 10 and 50 #mu#m, respectively. After irradiation, the parts exposed were dissolved in a liquid developer without affecting the nonirradiated parts. The shape and the rms roughness of the resulting structures were estimated by ...

Energy Technology Data Exchange (ETDEWEB)

The Micro-strip Metal Foil Detectors (MMFD) designed and used for the Beam Profile Monitoring (BPM) are discussed. The results obtained for the MMFDs produced by different technologies are presented. The MMFD deposited onto the 20 {mu}m thick Si-wafer has been used for the BPM of the 32 MeV alpha-particle beam at the MPIfK (Heidelberg) Tandem generator. Another MMFD with totally removed Si-wafer at the working area has been applied for the on-line X-ray BPM at the HASYLAB (DESY). One may conclude that the developed technology of the micro-strip metal detector manufacturing allows to provide non-destructive measurement of X-ray intensity distribution over area of up to 50 mm{sup 2} with an accuracy of 10-20 {mu}m with a possibility of its improvement by a factor 5. A sub-micron position resolution is expected by applying electron lithography for the strip pattern production.

International Nuclear Information System (INIS)

Focused ion beam (FIB) processes have been developed for Y--Ba--Cu--O superconductor films. A Y--Cu liquid metal ion source has been fabricated, using a Y_6_7 --Cu_3_3 eutectic alloy as the ion source. As-sputtered Y--Ba--Cu--O film etch rate ratios to GaAs(100) and Si(100) substrates are 0.28 and 1.4 for 130-keV Au"+ FIB ion etching, respectively. Y--Ba--Cu--O submicron patterns have been demonstrated by using FIB lithography and Cl_2 reactive ion beam etching. Moreover, a Y--Ba--Cu--O superconducting line with 4-#mu#m linewidth has been fabricated by annealing an as-sputtered Y--Ba--Cu--O line pattern. T/sub c/ control of Y--Ba--Cu--O film has been achieved by 200-keV Ne"+, using conventional ion implantation and 300 keV Si"+"+ FIB ion implantation.

Energy Technology Data Exchange (ETDEWEB)

Previously we have used atomic force anodisation lithography, with a self-assembled monolayer of hexadecyltrichlorosilane as a resist, to pattern silicon oxide nanostructures onto a p-type silicon (1 0 0) substrate. A condensation reaction was used to immobilise carbon nanotubes with high carboxylic acid functionality directly to the silicon oxide. A further condensation reaction using this surface attached the molecule ferrocenemethanol to the bound nanotubes. These new nanostructures were used as electrodes to observe the oxidation and reduction of ferrocene. However, because the small currents measured are near the detection limits of the electrochemical system used, important electrode kinetics could not to be obtained. A scribing approach made larger regions of oxidised silicon leading to the creation of larger scale patterned arrangements of carbon nanotubes allowing measurement of important electrochemical parameters such as electrode kinetics, electron ...

Wastenet

... 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 ...

International Nuclear Information System (INIS)

We present the results of a comprehensive study of the temperature dependences of the quantum efficiency for ultraviolet detectors based on GaAs, GaP and 4H--SiC Schottky structures, and on Si, GaAs p-n structures. For ultraviolet detectors based on Schottky structures, the quantum efficiency increases with increasing temperature for all photon energies, even including the semiconductor intrinsic absorption region. On the other hand, for ultraviolet detectors based on p-n structures, the quantum efficiency is practically temperature independent in the semiconductor intrinsic absorption region. The change in the quantum efficiency for the GaAs and Si detectors is less than 0.01% per degree. To explain the measurements, a variable trap occupancy model is presented. Subsurface imperfections of the semiconductor cause fluctuations in the profile of the conduction band and the valence band edges. In the presence of an electric ...

UK PubMed Central (United Kingdom)

Epidermal gamma delta T cells (γδ T) and Langerhans cells (LC) are immune cells altered by exposure to ultraviolet radiation (UVB), a powerful stressor resulting in immune suppression....Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Governments around the world will soon make decisions on policies that could determine the fate of the ozone layer-the Earth's shield from harmful ultraviolet radiation. The Vienna Convention for the Protection of the Ozone Layer, signed on March 22, 1985, created a framework for scientific cooperation and information exchange that will form the basis for a protocol for controlling substances thought to threaten the ozone layer. As of mid-1987, 29 countries had signed the Convention, including the major producers and users of chlorofluorocarbons (CFCs), the most important of suspect chemicals.

Energy Technology Data Exchange (ETDEWEB)

Polyacrylonitrile films have been spin cast and pyrolyzed to produce thin (500--1500 A) carbon films. These films have higher electrical conductivities than films produced by other methods at similar temperatures. The conductivity can be varied by at least four orders of magnitude by changing the pyrolysis temperature. Ultraviolet, infrared, and Raman spectroscopies were used to investigate the chemical structure of the films during different stages of processing.

Energy Technology Data Exchange (ETDEWEB)

The general n-point massless p-adic Feynman amplitude with arbitrary parameters of analytic regularization for each line is calculated. This result is presented in the form of a sum over hierarchies of a given graph. The structure of ultraviolet and infrared divergences of p-adic Feynman amplitudes is characterized and the star-triangle uniqueness identity in the p-adic case is derived. (orig.).

Energy Technology Data Exchange (ETDEWEB)

This paper gives details of the development of the Wartsila 32DF duel-fuel lean-burn engine that can burn liquid or gaseous fuels, and reports on the installation of four of the engines in Turkey. The combustion process, and the design of the gas admission, pilot fuel, cylinder control, air-fuel control, and engine control and monitoring systems are described. The advantages of the engine are discussed.

Energy Technology Data Exchange (ETDEWEB)

This patent describes a gas-diesel dual fuel engine apparatus having a diesel engine, a diesel fuel supply system including a diesel fuel injection pump, a gaseous fuel supply system including gaseous fuel regulating valve, and a governing and controlling device for governing the speed of the engine and controlling the switchover of the operation of the engine between a diesel fuel mode and a gaseous fuel mode.

Science.gov (United States)

This is the quarterly progress review report for Wolsung NPP 2, 3, 4 NSSS design and engineering which evaluates the performance of project and describes the project highlight, manpower loading status, design and engineering and project related meeting by...

International Nuclear Information System (INIS)

This guide explained the requirements for Off-Road Compression Ignition Engine Emission Regulations established under the Canadian Environmental Protection Act. The regulations are enforced by Environment Canada, which authorizes and monitors the use of the national emissions mark. The regulations prescribe standards for off-road engines that operate as reciprocating, internal combustion engines, other than those that operate under characteristics similar to the Otto combustion cycle and that use a spark plug or other sparking device. The regulations apply to engines that are typically diesel-fuelled and found in construction, mining, farming and forestry machines such as tractors, excavators and log skidders. Four different types of persons are potentially affected by the regulations: Canadian engine manufacturers; distributors of Canadian engines or machines ...

Science.gov (United States)

... Programmatic Terms and Conditions for the Materials Research Science and Engineering Centers (MRSEC ... NSF Grants Officer. 2. Program Description: Materials Research Science and Engineering Centers ...

Wastenet

...Electronic equipment,Embedded computer systems,Technology & Engineering,Automotive - General,COMPUTERS / Computer Engineering,TECHNOLOGY & ENGINEERING / Electronics ...

Energy Technology Data Exchange (ETDEWEB)

Hydrogen piston engines can be simultaneously optimized for improved thermal efficiency and for extremely low emissions. Using these engines in constant-speed, constant-load systems such as series hybrid-electric automobiles or home cogeneration systems can result in significantly improved energy efficiency. For the same electrical energy produced, the emissions from such engines can be comparable to those from natural gas-fired steam power plants. These hydrogen-fueled high-efficiency, low-emission (HELE) engines are a mechanical equivalent of hydrogen fuel cells. HELE engines could facilitate the transition to a hydrogen fuel cell economy using near-term technology.

Energy Technology Data Exchange (ETDEWEB)

This work reviews the differences in fuel economy between two direct injection diesel engine versions through the use of a First Law energy balance and a Second Law availability balance. Both experimental data and simulated results are used in the analysis. The use of an engine simulation allowed the important processes in each engine to be analyzed and a Second Law effectiveness calculated. The availability balances and effectiveness values are used to determine the effect of major engine components on the fuel economy. A comparison is also made with an ideal engine with selected perfect or reversible processes.

Science.gov (United States)

Engine flow simulation was provided by four separately mounted air ejectors connected to a high-pressure air supply. The engine nacelle center lines were ...

Science.gov (United States)

of the Intelligent Control System (ICS) for reusable rocket engines. .... the incoming measurements with corresponding estimates, a sensor failure can be ...

Science.gov (United States)

NSF-NIST Interaction in Chemistry, Materials Research, Molecular Biosciences, Bioengineering, and ... Laboratory (CSTL). Materials research is centralized in the Materials Science and Engineering ...

Science.gov (United States)

Graphitized thermal carbon black has also been reported by Kalaschinikova et al. (11) to have excellent adsorption properties for CI-C6 alkanes, ...

Science.gov (United States)

... CI Appendix D: Conference Attendees ..... D1 Appendix E: Structural Steel Connection Design on Federal Projects ..... El iv ...

Science.gov (United States)

NASA 1996 STTR Phase I. Proposal Number: 960022. Project Title: ADVANCED INTERNAL COMBUSTION ENGINE USING JET FUELS FOR LIGHT AIRCRAFT ...

British Library Electronic Table of Contents (United Kingdom)

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 Formula Not Shown 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.

ScienceCinema

@ work highlights Idaho National Laboratory employees and the jobs they perform.This segment features Robotic Software Engineer Miles Walton.

Energy Technology Data Exchange (ETDEWEB)

Solar ultraviolet radiation is damaging for living organisms due to its high energy pro each photon. The UV radiation is often separated into three regions according to the wavelength: UVC (200-280 nm), UVB (280-320 nm) and UVA (320-400 nm). The most hazardous part, UVC is absorbed completely in the upper atmosphere by molecular oxygen. UVB radiation is absorbed by atmospheric ozone partly, and it is reaching Earth`s surface, as UVA radiation. Besides atmospheric ozone, very important factors in determining the intensity of UVB radiation globally are the solar zenith angle and cloudiness. It may be calculated from global ozone changes that the clear-sky UVB doses may have enhanced by 10-15 % during spring and 5-10 % during summer at the latitudes of Finland, following the decrease of total ozone between 1979-90. The Finnish ozone and UV monitoring activities have become a part of international activities, especially the EU Environment and Climate Programme`s ...

Energy Technology Data Exchange (ETDEWEB)

The second list of objects in the Second Biurakan Spectral Sky Survey of the region centered on alpha 09h50m, delta +55 deg 00 arcmin is given. The list contains data on 110 objects and galaxies of a peculiar physical nature and 24 blue stars. The observations were made with the 40-52 arcsec Schmidt telescope of the Biurakan Astrophysical Observatory with a set of three objective prisms using Kodak IIIaJ and IIIaF emulsions sensitized in nitrogen. The area is found to contain 20 quasar candidates and four Seyfert galaxies, 27 blue stellar objects, 24 galaxies with an appreciable ultraviolet continuum, and 39 emission galaxies without appreciable ultraviolet radiation. The surface brightness of the quasars and Seyferts on the considered area down to the limiting magnitude 19.5 M is more than 1.5 per square degree with allowance for the already known quasars. The surface density of emission galaxies is about four per square degree. 7 references.

CERN Document Server

We present the general properties of the far-ultraviolet (FUV; 1370-1720A) continuum background over most of the sky, obtained with the Spectroscopy of Plasma Evolution from Astrophysical Radiation instrument (SPEAR, also known as FIMS), flown aboard the STSAT-1 satellite mission. We find that the diffuse FUV continuum intensity is well correlated with N_{HI}, 100 $\\mu$m, and H-alpha intensities but anti-correlated with soft X-ray. The strongest correlation is with the H-alpha emission, and the correlation of the diffuse background with the direct stellar flux is weaker than the correlation with other parameters. The continuum spectra are relatively flat. However, a weak softening of the FUV spectra toward some sight lines, mostly at high Galactic latitudes, is found not only in direct-stellar but also in diffuse background spectra. The diffuse background is relatively softer that the direct stellar spectrum. We also find that the diffuse FUV background averaged ...

Energy Technology Data Exchange (ETDEWEB)

Nanocrystalline ZnO films were fabricated via a simple method involving the oxidation of Zn films at a remarkably low temperature of 380 C. X-ray diffraction study confirmed that the Zn films were completely oxidized even at the low temperature of 380 C and the ZnO films fabricated were of polycrystalline wurtzite structure. Room temperature optical pumping using a frequency-quintupled Q-switched Nd:YAG laser ({lambda}=213 nm) exhibited that sharp peaks at around 3.12 eV emerged above excitation powers of {proportional_to}7 MW/cm{sup 2}, demonstrating lasing in the ZnO films. These results represent that the process is a simple, promising approach for fabricating ZnO of sufficient optical performance for use as ultraviolet (UV) light emitters and an alternative UV laser source; both are key components in short-wavelength photonic devices. (orig.)

CERN Document Server

We present ultraviolet spectra of Mira's companion star from the Space Telescope Imaging Spectrograph (STIS) instrument on board the Hubble Space Telescope (HST). The companion is generally assumed to be a white dwarf surrounded by an accretion disk fed by Mira's wind, which dominates the UV emission from the system. The STIS UV spectrum is dominated by numerous, narrow H2 lines fluoresced by H I Ly-alpha, which were not detected in any of the numerous observations of Mira B by the International Ultraviolet Explorer (IUE). The high temperature lines detected by IUE (e.g., C IV 1550) still exist in the STIS spectrum but with dramatically lower fluxes. The continuum fluxes in the STIS spectra are also much lower, being more than an order of magnitude lower than ever observed by IUE, and also an order of magnitude lower than fluxes observed in more recent HST Faint Object Camera objective prism spectra from 1995. Thus, the accretion rate onto Mira ...

CERN Document Server

An electroweak model with running coupling constants described by an energy dependent entire function is utraviolet complete and avoids unitarity violations for energies above 1 TeV. The action contains no physical scalar fields and no Higgs particle and the physical electroweak model fields are local and satisfy microcausality. The $W$ and $Z$ masses are compatible with a symmetry breaking $SU(2)_L\\times U(1)_Y \\rightarrow U(1)_{\\rm em}$, which retains a massless photon. The vertex couplings possess an energy scale $\\Lambda_W > 1$ TeV predicting scattering amplitudes that can be tested at the LHC.

Energy Technology Data Exchange (ETDEWEB)

This paper reports on the results of experiments into efficient higher-order anti-Stokes Raman conversion of tunable short-pulse XeCl laser radiation. The maximum output energy of the pumping laser, in which the radiation of a frequency-doubled dye laser is amplified by two XeCl laser amplifiers, is 55 mJ with a pulse duration of 1 ns FWHM. Using hydrogen gas as a Raman medium, a series of anti-Stokes lines up to the 12th order (121.5 nm) is generated in the vacuum ultraviolet (VUV) region. 16 references.

International Nuclear Information System (INIS)

The color centers, which are generated in yttrium-aluminium perovskite (YAP):Nd(1 at.%) and YAP:Er(50 at.%) crystals under the influence of ultraviolet and #gamma#-irradiation, have been studied by absorption spectroscopy. The generated color centers are both stable and transient at room temperature. It is shown that the transient color centers are mainly responsible for the decrease of laser generation efficiency of Nd:YAP and YAP:Er irradiated crystals, although physical mechanisms leading to efficiency decrease are different in these materials. (orig.)

British Library Electronic Table of Contents (United Kingdom)

Tb3+-activated Sr3AlO4F phosphors were synthesized by a high-temperature solid-state reaction method. The investigation of photoluminescence and cathodoluminescence indicates that these phosphors can be effectively excited by ultraviolet light and low-voltage electron beam. The phosphors exhibit a tunable-green emission. The luminescence behaviors are explained by the site occupancy of Tb3+ ions in the host crystal and the cross-relaxation of 5D3 to 5D4 state.

CERN Document Server

In situ optical absorption spectroscopy was used to study the generation of E' centres in amorphous SiO_2 occurring by photo-induced breaking of Si-H groups under 4.7eV pulsed laser radiation. The dependence from laser intensity of the defect generation rate is consistent with a two-photon mechanism for Si-H rupture, while the growth and the saturation of the defects are conditioned by their concurrent annealing due to reaction with mobile hydrogen arising from the same precursor. A rate equation is proposed to model the kinetics of the defects and tested on experimental data.

International Nuclear Information System (INIS)

We studied the optimum plasma conditions that are required for efficient high-order harmonic generation in platinum plume. Harmonics up to the 49th order (?=16.32 nm) are analyzed under various conditions of laser-plasma interaction. Time-resolved ultraviolet spectra of platinum plasma at both optimum and nonoptimum conditions of harmonic generation are presented. We calculated the ionization states of the plasma, free electron density, and singly charged ion density at different prepulse intensities and compared them with experimental results.

Science.gov (United States)

We explore autofluorescence endomicroscopy as a potential tool for real-time visualization of epithelial tissue microstructure and organization in a clinical setting. The design parameters are explored using two experimental systems--an Olympus Medical Systems Corp. stand-alone clinical prototype probe, and a custom built bench-top rigid fiber conduit prototype. Both systems entail ultraviolet excitation at 266 nm and/or 325 nm using compact laser sources. Preliminary results using ex vivo animal and human tissue specimens suggest that this technology can be translated toward in vivo application to address the need for real-time histology.

Energy Technology Data Exchange (ETDEWEB)

Petroleum resources are finite and, therefore, search for their alternative non-petroleum fuels for internal combustion engines is continuing all over the world. Moreover gases emitted by petroleum fuel driven vehicles have an adverse effect on the environment and human health. There is universal acceptance of the need to reduce such emissions. Towards this, scientists have proposed various solutions for diesel engines, one of which is the use of gaseous fuels as a supplement for liquid diesel fuel. These engines, which use conventional diesel fuel and gaseous fuel, are referred to as 'dual-fuel engines'. Natural gas and bio-derived gas appear more attractive alternative fuels for dual-fuel engines in view of their friendly environmental nature. In the gas-fumigated dual-fuel engine, the primary fuel is mixed outside the cylinder before it is ...

Energy Technology Data Exchange (ETDEWEB)

This paper deals with the control of an electromechanical valves engine. The control uses neural networks in order to build a non-linear model of engine filing which depends on the driven inlets. The aim is to build this real-time model and to integrate this model to a control system which performs an iterative inversion. (J.S.)

Energy Technology Data Exchange (ETDEWEB)

This review examines the characteristics of the compression-ignition type of dual-fuel engine and the combustion phenomena that affect these characteristics. The specific areas covered involve normal combustion processes, the nature and origin of engine knock, operation with LNG, and the effect of intake temperature on combustion efficiency and exhaust composition.

International Nuclear Information System (INIS)

... Polskiego Towarzystwa Fizycznego (Poland) Polskie Towarzystwo Fizyczne;

Wastenet

That would revert the trend back to petrol, or otto cycle engines .

International Nuclear Information System (INIS)

... fluidic control devices performance reactor control systems space propulsion

Wastenet

...to facilities using - Petrol and diesel industrial engines - Petrol and diesel light vehicles, commercial vehicles and trucks on the facility - Large stationary diesel and dual-fuel engines - Heavy-duty natural gas fired pipeline compressor engines and turbines First published in February 1999 Revised - August 2000 Version 2.3 - ...

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).

KoreaScience (Korea)

Full Text Available

Science.gov (United States)

... INFRARED THERMOMETERS AND TEMPERATURE CONTROLLERS--A POCKET-SIZE, PORTABLE INFRARED THERMOMETER, AND A ...

KoreaScience (Korea)

Full Text Available

International Nuclear Information System (INIS)

We derive stellar masses, ages, and star formation histories (SFHs) of massive early-type galaxies in the z = 1.237 RDCS1252.9-2927 cluster and compare them with those measured in a similarly mass-selected sample of field contemporaries drawn from the Great Observatories Origin Deep Survey South Field. Robust estimates of these parameters are obtained by comparing a large grid of composite stellar population models with 8-9 band photometry in the rest-frame near-ultraviolet, optical, and IR, thus sampling the entire relevant domain of emission of the different stellar populations. Additionally, we present new, deep U-band photometry of both fields, giving access to the critical far-ultraviolet rest frame, in order to empirically constrain the dependence of the most recent star formation processes on the environment. We also analyze the morphological properties of both samples to examine the dependence of their scaling relations on their mass ...

Energy Technology Data Exchange (ETDEWEB)

Test bed trials of the Sulzer RTA84 dual-fuel engine were successfully completed at the IHI Aioi engine works (Japan) in April 1986. This newly-developed engine-type, output range 15 to 40 MW, can be operated with both diesel or heavy oil and methane gas at comparable thermal efficiency and unchanged output. The RTA dual-fuel engine was developed in close collaboration between Sulzer Brothers Limited and its Japanese licenses. Intended for the propulsion of LNG carriers, where the boil-off gas from the ship's cargo is exploited for the generation of electricity in stationary plants, the RTA dual-fuel engines is an economic and reliable alternative to the steam or gas turbine. The performance of the engine is discussed.

Energy Technology Data Exchange (ETDEWEB)

Recently, utilization of natural gas, which is considered to be one of most important alternative fuels for petroleum, has been marked. As thermal efficiency of dual-fuel engine is higher than those of other prime movers with gaseous fuel, i.e., spark-ignited gas engine or gas turbine, it is possible to construct fuel-economical gas power plants with dual-fuel engines. However, its horsepower has been limited to the rather lower range. In 1984, NKK succeeded in developing large-sized dual-fuel engines based on the Pielstick PC4 diesel engine. The horsepower is 1200 HP/cyl, i.e. 21,600 HP for 18-cyclinder engine.

Wastenet

...Cummins Turbo Technologies launches new family of turbochargers for smaller diesel engines at IAA Hannover, public service, publicservice.co.uk Cummins Turbo Technologies ...launches new family of turbochargers for smaller diesel engines at IAA Hannover Cummins Turbo Technologies launches new family of turbochargers for smaller diesel engines at IAA ...Facebook Delicious Cummins Turbo Technologies launches new family of turbochargers for smaller diesel engines at IAA Hannover Cummins Turbo Technologies, a global engineering leader ...turbocharger technology, launched a new range of diesel turbochargers specifically designed for diesel engines from 2 -5 litre capacity today at IAA Hannover. Cummins ...

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 ...

Science.gov (United States)

Divergence between aircraft engine emission regulations proposed by EPA and ICAO is discussed. Every engine, upon entering service, requires a certificate as to its compliance with emission standards. It is shown that despite the large variability in the measurements, it is possible to devise a certification procedure requiring the testing of one engine only. Statistical modeling of such a test at the 5% significance level is described. Values of the parameter standard deviation/mean recommended as certification standards for various pollutants are given. Features of a rational certification scheme to be formulated are outlined.

Wastenet

... John Cannaday and Ken Weddle present the framework for a Product Design Engineering project (http://engineering.dartmouth.edu/~teps/images/ProductDesign.pdf) for high school students which may have relevance at a more advanced level. David Price has created a Mechanical Engineering Design (http://www.soton.ac.uk/~cds/) site containing engineering design notes. The Virtual Reality Engineering Library Home Page at the University of Bristol (http://www.dig.bris.ac.uk/virtual_lib/) is a library ...

International Nuclear Information System (INIS)

This paper discusses key methods for sustaining quality engineering data, the fundamental principles that these methods are based on, and the methods for supporting the performance of nuclear power plants by the provision of quality engineering data at all times. The concept of an 'engineering data foundation', and a Configuration Management data model are developed. The concepts and methods for managing the integrity of engineering data across many different databases and document systems are developed, including the key concepts of data-positions and data-values, Master Data and Copy Data, and the concept of a 'partnership between people and technology'. (author). 7 refs., 1 tab., 2 figs.

Energy Technology Data Exchange (ETDEWEB)

The paper considers the cyclic variations in performance parameters of a dual fuel engine fuelled with methane. It is shown that such an engine does display cyclic variations that are greater than the corresponding diesel operation, yet smaller than comparable spark ignition operation. The extent of cyclic variation in peak cylinder pressure and ignition delay increases, for any power output, as the pilot diesel quantity is reduced and the extent of gas substitution is increased. The use of extremely small pilots in the unmodified engine can lead to erratic engine performance. Greater cyclic variations are associated with low lead rather than high load operation.

Energy Technology Data Exchange (ETDEWEB)

Direct injection diesel engines power most of the heavy-duty vehicles. Due to their superior fuel economy, high power density and low carbon dioxide emissions, turbocharged, small bore, high speed, direct injection diesel engines are being considered to power light duty vehicles. Such vehicles have to meet stringent emission standards. However, it is difficult to meet these standards by modifying the in-cylinder thermodynamic and combustion processes to reduce engine-out emissions. After-treatment devices will be needed to achieve even lower emission targets required in the production engines to account for the anticipated deterioration after long periods of operation in the field. To reduce the size, mass and cost of the after-treatment devices, there is a need to reduce engine-out emissions and optimize both the engine and the aftertreatment devices as one ...

International Nuclear Information System (INIS)

Full Text: Smallstage Dualbeam (SDB) systems, that is a Focussed Ion Beam column coupled with a SEM column, have been around for about five years now. There impact on the Semiconductor industry has been enormous, with virtually every lab having a SDB to produce, characterise and analyse cross sections and TEM samples on the Nano-scale. But what about other industries? What else can SDB system be used for? The SEM column in itself is a very powerful tool for sample characterisation, modification and analysis. An electron beam from a Tungsten or Thermal Field Emission source has enough current to allow sophisticated patterns to be created in photo-resist samples, a process known as lithography. The current is also high enough to allow for a process known as Electron Beam Induced Deposition (EBID), where the beam interacts with an introduced gas and material is deposited in a controlled manner on the sample. With the addition of the Focussed Ion Beam (FIB) direct ...

Energy Technology Data Exchange (ETDEWEB)

Microfabrication processes for Y-Ba-Cu-O films have been investigated, using ion-beam techniques. High-{Tc} superconducting lines as narrow as 0.8 {mu}m have been fabricated from epitaxial YBa{sub 2}Cu{sub 3}O{sub 7 {minus} {ital y}} films by Ar ion-beam etching (IBE), combined with focused ion-beam (FIB) lithography. The resulting lines, 1.3 {mu}m wide and 2 mm long, showed a zero resistance temperature of 81 K and a critical current density of 1.9 {times} 10{sup 4} A/cm{sup 2} at 77.3 K. Maskless etching was carried out using 130-keV au{sup +} focused ion-beam (FIB) with a 0.1-{mu}m-diameter beam. A 50-nm-thick film was patterned into 0.3-{mu}m-wide lines at a dose of 5 {times} {sup 16} ions/cm{sup 2}. In comparison with Ar IBE, Cl{sub 2} reactive ion-beam etching (RIBE) exhibited an enhancement effect in sputtering yield. Ion implantation with 300-keV Si{sup + +} FIB also indicated the possibility to produce submicrometer patterns by selectively modifying film ...

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 ...

Energy Technology Data Exchange (ETDEWEB)

Partial combustion of biomass in the gasifier generates producer gas that can be used for heating purposes and as supplementary or sole fuel in internal combustion engines. In this study, the potential of coir-pith and wood chips as the feedstock for gasifier is analyzed. The performance of the gasifier-engine system is analyzed by running the engine for various producer gas-air flow ratios and at different load conditions. The system is experimentally optimized with respect to maximum diesel savings and lower emissions in the dual fuel mode operation while using coir-pith and wood chips separately. The performance and emission characteristics of the dual fuel engine are compared with that of diesel engine at different load conditions. Specific energy consumption in the dual fuel mode of operation is found to be in the higher side at all load conditions. The brake thermal efficiency ...

Energy Technology Data Exchange (ETDEWEB)

A natural gas and diesel dual-fuel turbocharged compression ignition (CI) engine is developed to reduce emissions of a heavy-duty diesel engine. The compressed natural gas (CNG) pressure regulator is specially designed to feed back the boost pressure to simplify the fuel metering system. The natural gas bypass improves the engine response to acceleration. The modes of diesel injection are set according to the engine operating conditions. The application of honeycomb mixers changes the flowrate shape of natural gas and reduces hydrocarbon (HC) emission under low-load and lowspeed conditions. The cylinder pressures of a CI engine fuelled with diesel and dual fuel are analysed. The introduction of natural gas makes the ignition delay change with engine load. Under the same operating conditions, the emissions of smoke and NO{sub x} from the dual-fuel ...

Energy Technology Data Exchange (ETDEWEB)

As part of a comprehensive simulation of a prototype locomotive propulsion system, a detailed model has been developed which predicts the dynamic response of an experimental 2-stroke, turbocharged and intercooled diesel engine. Engine fueling and brake torque are computed from regression equations derived from an extensive data base. Corrections are applied to the calculated steady-state torque to account for dynamic deviations of in-cylinder trapped air-fuel ratio from the steady-state value. The engine simulation accurately represents the operation of the turbo-charger, which is gear-driven at low turbocharger speeds, and freewheels through an overrunning clutch when exhaust energy accelerates the turbocharger beyond its geared speed. Engine fueling level, ie, rack, is determined from a dynamic simulation of an electrohydraulic governor which responds to the difference between the desired and the ...

Energy Technology Data Exchange (ETDEWEB)

This paper describes a practical knowledge on gas engine performance and combustion characteristics which are required by experimental studies for two types of developed gas burning engines, i. e. a spark ignited gas engine and a dual fuel engine, and also introduces their practical use and application. As for dual fuel engine performance, a manifold air pressure of about 27% was decreased, a scavenging ratio of 23% reduced and an exhaust temperature at the turbine inlet on 14% was increased at the gas engine operation under the mean effective cylinder pressure of 1.22 MPa in comparison with the diesel operation. Furthemore, empirical data on the effect of excess air ration on the engine performance and combustion characteristics, a risk of knocking during changing over on the dual fuel engine operation, and the rated ...

Energy Technology Data Exchange (ETDEWEB)

Testbed trials of the Sulzer RTA84 dual-fuel engine were successfully completed at the IHI Aioi engine works (Japan) in April 1986. This newly-developed engine, output range 15 to 40 MW, can be operated with both diesel or heavy oil and methane gas at comparable thermal efficiency and unchanged output. The RTA dual-fuel engine was developed in close collaboration between Sulzer Brothers Limited, Switzerland and its Japanese licensees Ishikawajima-Harima Heavy Industries Co. Ltd. (IHI), Nippon Kokan KK (NKK) and Sumitomo Heavy Industries Ltd. (SHI). Intended for the propulsion of LNG carriers, where the boil-off gas from the ship's cargo is exploited or for the generation of electricity in stationary plants, the RTA dual-fuel engine is an economic and reliable alternative to the steam or gas turbines.

Energy Technology Data Exchange (ETDEWEB)

A process is described for converting organic waste into a combustible gas for use in a heavy duty thermal engine. The engines best suited for this operation are of the dual-fuel type whose output power results from the simultaneous work of 2 combustibles. The gas flow rate is controlled by the desired power output, while diesel fuel injection remains constant regardless of engine load. The low BTU gas produced by the gasification of dry wastes is a mixture of CO, H/sub 2/ CH/sub 4/, CO/sub 2/ and N/sub 2/. Diesel fuel savings under usual operating conditions is no less than 80% of the consumption of conventional diesel engines of identical power. Characteristics of the low Btu gas engines are described as are the characteristics of the gasifying equipment. Applications for this process are suggested. (DMC)

Energy Technology Data Exchange (ETDEWEB)

The diesel engine is the most efficient device for converting chemical energy stored in liquid hydrocarbon fuels into useful work. Up to 50% of the energy in the fuel is converted into output shaft work. The modern diesel engine is twice as efficient as the early diesel engines and produces as much as sixty times as much power for a given cylinder size. These developments have, in recent years, been accompanied by a substantial reduction in the noxious elements in the exhaust gas so that engines are now, relatively speaking, ecologically clean. The developments have centred around exhaust gas turbocharging and improved fuel injection systems, but recent work on low-heat-rejection engines has resulted in significant advances in structural ceramics and in high-temperature lubricating oil, as well as an enhanced understanding of heat transfer in high-temperature combustion chambers. ...

Energy Technology Data Exchange (ETDEWEB)

An investigation of current dual-fuel natural gas/diesel engine design, performance, and emissions was conducted. The most pressing technological problems associated with dual-fuel engine use were identified along with potential solutions. It was concluded that dual-fuel engines can achieve low NOx and particulate emissions while retaining fuel-efficiency and BMEP levels comparable to those of diesel engines. The investigation also examined the potential economic impact of dual-fuel engines in diesel-electric locomotives, marine vessels, farm equipment, construction, mining, and industrial equipment, and stand-alone electricity generation systems. Recommendations for further additional funding to support research, development, and demonstration in these applications were then presented.

British Library Electronic Table of Contents (United Kingdom)

This project is about the simulation design of an engine control unit (ECU) for an Otto cycle engine with electronic fuel injection (EFI). The simulation includes a model for the ECU as well as physical parameters of the engine, which allows closed-loop control and monitoring of various systems.This simulation has been realized using Simulink and Stateflow, which are components of Mathworks' MATLAB software.The program allows control of various parameters of the ECU, as well as the simulation of failures to verify that the designed ECU is fault-tolerant and can control the engine using an open loop control. The main function the ECU provides is fuel metering.Subsequently, this program could be used as a tool to quickly develop and test models of ECU in order to control an engine in laborat...

International Nuclear Information System (INIS)

In the present study, surfaces of cylinder head, piston, exhaust and inlet valve of a four-stroke, direct injection, single cylinder diesel engine were coated with molybdenum (Mo) by plasma spray method. Thus, thermal barrier characteristic was brought to these parts. Variances in performance and emission values of cotton methyl ester and 2D fuel mixtures were studied in the ceramic coated and uncoated engines under the same running conditions. Performance (6.0% for specific fuel consumption) and emission values (up to 18.0% for CO, 8.0% for smoke density) of the test fuel were improved in the coated engine compared with the uncoated engine. NO_x increase (4.5%) with the increased temperatures expected in the coated engine.

Energy Technology Data Exchange (ETDEWEB)

The original plan for support of research in geothermal reservoir engineering, GREMP, is reviewed and compared with accomplishments to date. A commentary on the comparison and an updated plan are presented. Also included are a justification of the updated plan and a revised management plan. (MHR)

Energy Technology Data Exchange (ETDEWEB)

The use of vegetable oils as a fuel in diesel engines causes some problems due to their high viscosity compared with conventional diesel fuel. Various techniques and methods are used to solve the problems resulting from high viscosity. One of these techniques is fuel blending. In this study, a blend of 50% sesame oil and 50% diesel fuel was used as an alternative fuel in a direct injection diesel engine. Engine performance and exhaust emissions were investigated and compared with the ordinary diesel fuel in a diesel engine. The experimental results show that the engine power and torque of the mixture of sesame oil-diesel fuel are close to the values obtained from diesel fuel and the amounts of exhaust emissions are lower than those of diesel fuel. Hence, it is seen that blend of sesame oil and diesel fuel can be used as an alternative fuel successfully in a diesel ...

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)

Compliance mismatch is a significant challenge to long-term patency in small-diameter bypass grafts because it causes intimal hyperplasia and ultimately graft occlusion. Current engineered grafts...Full Text Available

UK PubMed Central (United Kingdom)

We report the use of cysteine-substituted mutants in conjunction with in situ oxidation to determine the physical proximity of a pair of engineered cysteines in the pore region of the voltage-gated...Full Text Available

Science.gov (United States)

The U.S. government technical report is a primary means by which the results of federally funded

UK PubMed Central (United Kingdom)

Recently, there has been significant progress in the development of genetically-engineered mouse (GEM) models. By introducing genetic alterations and/or signaling alterations of human pancreatic cancer...Full Text Available

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 combustion to reduce fuel consumption and exhaust emissions, and the ...

Science.gov (United States)

This volume is a summary of the results of the final report of the Energy Engineering Analysis Program (EEAP) Study of 30 selected dining facilities at Fort Campbell, Kentucky.

Energy Technology Data Exchange (ETDEWEB)

NO[sub x] emission legislation requirements for large-bore internal combustion engines have required engine manufacturers to continue to develop and improve techniques for exhaust emission reduction. This paper describes the development of the Cooper-Bessemer Clean Burn gas-diesel (dual-fuel) engine that results in NO[sub x] reductions of up to 92 percent as compared with an uncontrolled gas-diesel engine. Historically, the gas-diesel and diesel engine combustion systems have not responded to similar techniques of NO[sub x] reduction that have been successful on straight spark-ignited natural gas burning engines. NO[sub x] levels of a nominal 1.0 g/BHP-h, equal to the spark-ignited natural gas fueled engine, have been achieved for the gas-diesel and are described. In addition, the higher opacity exhaust plume characteristic of gas-diesel ...

Energy Technology Data Exchange (ETDEWEB)

This book contains 8 papers including the topics of: Spray and Flame Structure in Diesel Combustion; Experimental and Theoretical Investigations of Diesel Injection Transients; Lead-Fuel Governor System - Dual-Fuel Engine; Fuel Spray Modeling in Swirling Flows.

UK PubMed Central (United Kingdom)

Developing in vitro engineered hepatic tissues that exhibit stable phenotype is a major challenge in the field of hepatic tissue engineering. However, the rapid dedifferentiation of...Full Text Available

Science.gov (United States)

... comparative analysis is made of the sensitivity of two types of spectrometers: instruments employing coherent spontaneous radiation, and classical ...

KoreaScience (Korea)

Full Text Available

Energy Technology Data Exchange (ETDEWEB)

By setting up a fully indicated, modern passenger car diesel engine, Mahle has created the basis for systematically testing current and future engine technologies. The experimental set-up has both an integrated high- and low-pressure EGR circuit and an open engine control unit, thus enabling efficient development of new systems under real-world conditions. The advantages of this comprehensive approach are illustrated below, using the example of different EGR technologies tested. (orig.)

Science.gov (United States)

... ENGINEERING. Personal Author(s) : Ogino,Koji ; Cadzow,James A. Report Date : 1980. Pagination or Media Count : 18. ...

International Nuclear Information System (INIS)

1974. 19 p. United States Anon. American Society of Mechanical Engineers.;

CERN Document Server

Images from 18/03/1998 to 27/08/1998

Science.gov (United States)

... without the problem of purple plague. The Au-Ni-In evaporated ... surface and bonding degradation (purple plague) St step-stress ...

Science.gov (United States)

Before working at JPL he was the Chief Engineer for the Milstar Satellite Avionics and several Military space programs. His technical background is in ...

International Nuclear Information System (INIS)

... compilation fission products j codes mixed oxide fuels neutron reactions

Energy Technology Data Exchange (ETDEWEB)

This patent describes an ignition system of an internal combustion engine which consists of: a permanent magnet supported by a rotary member of the engine adapted to rotate in synchronism with a rotary shaft of the engine; a generating coil for generating an electromotive force to produce an electric current as the permanent magnet acts on the generating coil during the rotation of the rotary member; an ignition capacitor charged by the electric current generated by the generating coil; a thyristor caused to turn on by a counter electromotive force generated by the generating coil to thereby cause the ignition capacitor to begin to discharge; and an ignition coil generating a high voltage as the ignition capacitor begins to discharge, to cause a spark discharge to take place in an ignition plug of the internal combustion engine.

Science.gov (United States)

No abstract available.

Science.gov (United States)

... projects that will result in the reduction of energy consumption in compliance with the objectives set forth in the Army Facilities Energy Plan, without ...

Energy Technology Data Exchange (ETDEWEB)

Information that describes the use of the Otto cycle engines in transportation is summarized. The transportation modes discussed in this report include the following: automobiles, light trucks, heavy trucks, marine, recreational vehicles, motorcycles, buses, aircraft, and snowmobiles. These modes account for nearly 100% of the gasoline and LPG consumed in transportation engines. The information provided on each of these modes includes descriptions of the average energy conversion efficiency of the engine, the capital stock, the amount of energy used, and the activity level as measured in ton-miles. Estimates are provided for the years 1980 and 2000.

International Nuclear Information System (INIS)

... Tohoku University, Graduate School of Engineering, Sendai, Miyagi (Japan)

Science.gov (United States)

extravehicular activity; an exploding bridgewire firing unit for rocket engines ; a pressure transducer that can withstand the 6000 OF temperiiture ...

Energy Technology Data Exchange (ETDEWEB)

The design changes of the improved 2,5 l direct injection Diesel engine with the nominal power output of 52 kW and a maximum torque of 143 Nm are described. This engine which is installed in the Ford Transit meets all relevant exhaust emission standards that are presently in effect. (orig.).

Energy Technology Data Exchange (ETDEWEB)

This paper introduces in detail the compression performance of biogas, the application of compressed biogas to the compression-ignition engine and the possibility as well as the necessity of using compressed biogas. Moreover, the paper also goes further into some problems about the power increasing, efficiency raising and their social, economic and ecological beneficial results, when the compressed biogas is used in the compression ignition-dual fuel engine.

Wastenet

...direct-injection systems Atomisation from hole-type nozzles (gasoline and diesel) under cavitating flow conditions Spray-wall interaction in gasoline direct injection engines Spray-wall interaction in direct-injection diesel engines Evaporation of multi-component fuels Cavitation in diesel injectors Nozzle flow, air motion, spray development and combustion in marine diesel engines ...

Energy Technology Data Exchange (ETDEWEB)

This proceedings CD ROM contains 127 papers on developing and evaluating engineering approaches to wetlands and river restoration. The latest engineering developments are discussed, providing valuable insights to successful approaches for river restoration, wetlands restoration, watershed management, and constructed wetlands for stormwater and wastewater treatment. Potential solutions to a wide variety of ecosystem concerns in urban, suburban, and coastal environments are presented.

Energy Technology Data Exchange (ETDEWEB)

Some 200 visitors attended the official opening of a new diesel engine driven cogeneration plant in the city of Hamburg at the end of March. The dual fuel engine built by Blohm+Voss will supply 7.7 MW of electricity to the grid and 8.26 MW of thermal power to generate steam and hot water. (author)

Energy Technology Data Exchange (ETDEWEB)

At HMC, fundamental research on the hydrogen fueled engine and vehicle has been carried out. For this engine, solenoid driven injector is used to supply gaseous hydrogen into the cylinder and various operating parameters have been changed to study the combustion characteristics of hydrogen. After these experiments on the engine, a hydrogen fueled vehicle has been constructed and it is controlled by an ECU. The amount of emission from the hydrogen vehicle with stoichiometric operation is less than 1/3 of the ULEV legislation.

Energy Technology Data Exchange (ETDEWEB)

This document describes the 2003 SNL ASCI Software Quality Engineering (SQE) assessment of twenty ASCI application code teams and the results of that assessment. The purpose of this assessment was to determine code team compliance with the Sandia National Laboratories ASCI Applications Software Quality Engineering Practices, Version 2.0 as part of an overall program assessment.

British Library Electronic Table of Contents (United Kingdom)

The meiotic spindle in the oocyte is composed of microtubules and plays an important role during chromosome alignment and separation at meiosis. Polarized light microscopy (PLM) could be useful for a non-invasive evaluation of the meiotic spindle and may allow removal of nuclear structures without fluorochrome staining and ultraviolet exposure. In this study, PLM was used to assess its potential application in porcine reproductive technologies. The objectives of the present study were to assess the efficiency of PLM to detect microtubule-polymerized protein in in vitro-matured porcine oocytes; to examine its effects on the oocyte developmental competence; to select oocytes based on the presence of the meiotic spindle detected by PLM; and to assess the efficiency oocyte enucleation assisted...

International Nuclear Information System (INIS)

The effects of eight chemicals on the inactivation rate of ultraviolet radiation on the colony building capabilities of two strains of Saccharomyces cervisae - a wild type strain and a mutant deficient in excision repair - were studied. The insecticide methoxychlor, the herbicide 2,4-dichlorophenoxyacetic acid, the fungicide pentachlorophenol and its metabolite tetrachlorohydroquinone, as well as the chemicals acrylonitrile and 2,3-dichloro-1-propene have no significant impact on the effects of UV radiation in Saccharomyces cerevisae. Depending on the concentration, trichloroethylene increases the sensitivity to UV radiation. The herbicide paraquat provides efficient protection against UV radiation at concentrations where a toxic effect cannot be observed even without UV. The results were rather similar for both strains. (orig.).

CERN Document Server

We present experimental studies on the photoionization and photodissociation processes (photodestruction) of gaseous amino acids and nucleobases in interstellar and interplanetary radiation conditions analogs. The measurements have been undertaken at the Brazilian Synchrotron Light Laboratory (LNLS), employing vacuum ultraviolet (VUV) and soft X-ray photons. The experimental set up basically consists of a time-of-flight mass spectrometer kept under high vacuum conditions. Mass spectra were obtained using photoelectron photoion coincidence technique. We have shown that the amino acids are effectively more destroyed (up to 70-80%) by the stellar radiation than the nucleobases, mainly in the VUV. Since polycyclic aromatic hydrocarbons have the same survival capability and seem to be ubiquitous in the ISM, it is not unreasonable to predict that nucleobases could survive in the interstellar medium and/or in comets, even as a stable cation.

British Library Electronic Table of Contents (United Kingdom)

The light-emitting properties of cubic silicon carbide films grown by vacuum vapor phase epitaxy on Si(100) and Si(111) substrates under conditions of decreased growth temperatures (T gr ? 900?700?C) have been discussed. Structural investigations have revealed a nanocrystalline structure and, simultaneously, a homogeneity of the phase composition of the grown 3C-SiC films. Photoluminescence spectra of these structures under excitation of the electronic subsystem by a helium-cadmium laser (?excit = 325 nm) are characterized by a rather intense luminescence band with the maximum shifted toward the ultraviolet (?3 eV) region of the spectral range. It has been found that the integral curve of photoluminescence at low temperatures of measurements is split into a set of Lorentzian components. Th...

Science.gov (United States)

Oxide charge on the sidewalls of SiO{sub 2} embedded silicon wires with 20x20 nm{sup 2} cross section is shown to influence the Schottky barrier height for Pd{sub 2}Si/Si junctions positioned on the end surfaces of the wires. Compared with results on planar silicon surfaces, the electron barrier height is 0.3 eV lower for wires investigated as fabricated. By increasing the oxide charge through irradiation by ultraviolet light, the electron barrier decreases by an additional 0.15 eV and the hole barrier correspondingly increases by about the same amount. The phenomenon is explained by assuming an oxide charge density in the range of 10{sup 12} cm{sup -2}.

International Nuclear Information System (INIS)

A position-sensitive event-counting electronic readout system for microchannel plates (MCPs) is described that offers the advantages of high spatial resolution and fast time resolution. The technique relies upon a four-quadrant electron-collecting anode located behind the output face of the microchannel plate, so that the electron cloud from each detected event is partly intercepted by each of the four quadrants. The relative amounts of charge collected by each quadrant depend on event position, permitting each event to be localized with two ratio circuits. A prototype quadrant anode system for ion, electron, and extreme ultraviolet imaging is described. The spatial resolution achieved, approx. =10 #mu#, allows individual MCP channels to be distinguished.

Science.gov (United States)

uv irradiation (365 nm) of air-saturated methanol solutions of 20 drugs absorbing in the 300 to 400 nm region gave rise to oxygen uptake, as determined with a polarographic oxygen electrode. The drugs were tested for photosensitizing capability by either a Type I (free radical) or a Type II (single molecular oxygen) mechanism. This testing was done by the inclusion of either acrylamide or 2,5-dimethylfuran in the irradiated drug solution, with observation of the subsequent polymerization or oxidation, respectively. Phenothiazine and thiazide derivatives appear capable of photosensitization by both mechanisms; promethazine, trifluoperazine, and furosemide show relatively high reactivity. Diazepam (weak), hexachlorophene, aminacrine, pyrilamine, tetracycline, demeclocyline, quinine, and anthracene (strong) react only by a Type II mechanism, with a photosensitizing efficiency increasing in the order given. A correlation appears to exist with reports of in vivo photosensitivity.

Energy Technology Data Exchange (ETDEWEB)

An investigation was made of the accumulation of laser damage to transparent polymers irradiated with nanosecond pulses from neodymium and ruby lasers. The damage was investigated by the method of scattering and luminescence in the visible and near ultraviolet parts of the spectrum. It was established that there were two stages in laser damage by repeated irradiation with pulses of intensity below the single-shot damage threshold. An absorbing defect evolved during the first stage in such a way as to create a thermal instability in the surrounding matrix. During the second stage this thermal instability caused spatial growth of laser damage because of propagation of an ionization-inducing absorption wave with a front traveling at the rate governed by the electron component of the thermal conductivity.

Energy Technology Data Exchange (ETDEWEB)

Cold spray was employed as a novel low temperature approach to deposit titanium dioxide (TiO{sub 2}) photocatalytic film. The film microstructure was characterized using X-ray diffraction and scanning electron microscopy. The photocatalytic performance was examined through acetaldehyde degradation under ultraviolet illumination. Results showed that TiO{sub 2} film was successfully deposited on substrate surface through cold spray. The film thickness reached up to 15 {mu}m. The film presented a rough surface and porous structure. Owing to the low temperature of spray powder, no phase and particle size changes occurred to TiO{sub 2} during deposition. It was found that the cold-sprayed TiO{sub 2} film was active for photodegradation of acetaldehyde.

CERN Document Server

We review and extend in several directions recent results on the asymptotic safety approach to quantum gravity. The central issue in this approach is the search of a Fixed Point having suitable properties, and the tool that is used is a type of Wilsonian renormalization group equation. We begin by discussing various cutoff schemes, i.e. ways of implementing the Wilsonian cutoff procedure. We compare the beta functions of the gravitational couplings obtained with different schemes, studying first the contribution of matter fields and then the so-called Einstein-Hilbert truncation, where only the cosmological constant and Newton's constant are retained. In this context we make connection with old results, in particular we reproduce the results of the epsilon expansion and the perturbative one loop divergences. We then apply the Renormalization Group to higher derivative gravity. In the case of a general action quadratic in curvature we recover, within certain approximations, the known ...

Energy Technology Data Exchange (ETDEWEB)

The authors report experimental results on a high gradient 17 GHz RF photocathode gun. The photocathode RF gun is a novel electron beam source intended to meet the requirements set by future high-energy linear colliders and next generation free electron lasers. A coupled pair of pillbox TM{sub 010}-like resonators is excited by sidewall coupled microwaves at 17 GHz. A picosecond ultraviolet laser pulse illuminates one wall of the structure at the axis of symmetry. Electrons are released by the photoelectric effect and are accelerated by the electric field of the microwaves in the cavity. The high frequency of operation raises the RF breakdown limit allowing strong electric fields to be used. In turn, the intense fields result in rapid acceleration of the electrons to relativistic speeds and reduced space charge induced emittance growth.

British Library Electronic Table of Contents (United Kingdom)

Plasma polymerization of aniline is carried out in a radiofrequency plasma reactor and the effect of polymerization time is examined in the structural, optical and optoelectronic properties of deposited films. Conjugated structures of polyaniline like films are obtained with unique and broad optical absorption band in the ultraviolet and entire visible region. The width of the absorption band increases and hence the optical band gap decreases with polymerization time. The optical constants are extracted by Swanepoel method and the optical dispersion parameters are determined by employing the Wemple-DiDomenico single oscillator model. The films exhibit similar thermal stability in air and argon atmosphere in the region of interest for optoelectronic applications. The photoluminescence study...

International Nuclear Information System (INIS)

#epsilon#_m(Ce"4"+) values of the ceric-cereus system have been measured and the experimental procedure is described. Both routine titration method and electrochemical measurement were used. Some interference factors, such as ultraviolet, acidity and temperature, were studied as well. The temperature coefficient of #epsilon#_m(Ce"4"+) value in this experiment is about -0.1% degree C"-"1. A statistic analysis was made for 24 experimental values of #epsilon#_m(Ce"4"+) and a Gaussian distribution was found. Ultimately, an average molar extinction coefficient of 553.2 +- 1.3 m"2#centre dot#mol"-"1 was obtained at #approx#320 nm in 0.4 mol/L H_2SO_4 system, with a relative standard deviation of 0.24% (95% confidence level) and a total uncertainty of 1.5%.

Energy Technology Data Exchange (ETDEWEB)

The construction and the development of a UV free electron laser have been started under the cooperation of Nihon U, KEK, PNC, ETL and Tohaku U. The project requires a 100MeV S-band electron linear accelerator to expand the oscillation of FEL using fundamental mode to the UV region. The injection system consists of a thermionic RF-gun with a LaB cathode and an {alpha} magnet for magnetic bunching. We are studying to reduce the back-bombardment electrons to realize the macropulse length of 20{mu}sec. Electron beams, up to the energy of 100MeV, are injected into the optical oscillators. Changing the accelerating energy and/or undulator parameters, this system will cover the range from infrared to ultraviolet for the applications in various fields.

British Library Electronic Table of Contents (United Kingdom)

Background. Reports of positive patch test and photopatch test reactions to the chemical ultraviolet filter octocrylene have increased during the last decade. Little is known about the reason for octocrylene's allergenic activity. Objectives. To present and discuss the results of patch tests and photopatch tests with octocrylene, and to investigate the possible cause of its allergenic properties. Methods. Results of patch tests and photopatch tests with octocrylene in patients with adverse skin reactions to sunscreen products and/or ketoprofen were collected. The allergenic potency of octocrylene was investigated in the murine local lymph node assay (LLNA). Chemical reactivity assays were used to mimic octocrylene's interaction with biomolecules. Results. We report 23 cases of positive tes...

British Library Electronic Table of Contents (United Kingdom)

Absorption coefficient data are presented for molecular oxygen at temperatures between 1100 and 2000K and discrete wavelengths between 211 and 235nm. Measurements were made behind reflected shock waves using broad-linewidth ultraviolet laser radiation generated from a frequency-quadrupled, tunable, pulsed Ti:Sapphire laser. Test mixtures consisting of 15% O"2, 15% He and balance Ar were used to minimize the influence of vibrational relaxation on the reflected shock temperature. The experimental results are in good agreement with theoretical calculations and confirm that discrete features from the Schumann-Runge system dominate between 211 and 235nm at temperatures higher than 1100K.

International Nuclear Information System (INIS)

Studies of asphalt emulsion sealants conducted by the Pacific Northwest Laboratory have demonstrated that the sealants are effective in containing radon and other potentially hazardous material within uranium tailings. The laboratory and field studies have further demonstrated that radon exhalation from uranium tailings piles can be reduced by greater than 99% to near background levels. Field tests at the tailings pile in Grand Junction, Colorado, confirmed that an 8-cm admix seal containing 22 wt% asphalt could be effectively applied with a cold-mix paver. Other techniques were successfully tested, including a soil stabilizer and a hot, rubberized asphalt seal that was applied with a distributor truck. After the seals were applied and compacted, overburden was applied over the seal to protect the seal from ultraviolet degradation.

Energy Technology Data Exchange (ETDEWEB)

For the purpose of solving the limitations such as shape and dimension for magnetic compact fabricated by conventional anisotropic forming under magnetic orienting field, the feasibility of a new magnetic forming process was studied. Ferrite powder mixed with UV resin was compacted in the die mold and followed by alignment under the magnetic field. Effects of viscosity of UV resin and forming condition on magnetic characteristics of the compact was investigated. Maximum degree of alignment for the ferrite powder reached to 0.826. It was predicted that the proposed method had make it possible to fabricate a high performance magnet having the anisotropic alignment of the magnetic powder. The UV resin is desirable to have low viscosity, good properties such as formability and configuration stability for the compact and also parting- ability between the metal mold and the compact. (author)

British Library Electronic Table of Contents (United Kingdom)

We report on characterization of a set of AlGaN/GaN multiple-quantum-well (MQW) photodetectors. The model structure used in the calculation is the p-i-n heterojunction with 20 AlGaN/GaN MQW structures in i-region. The MQW structures have 2nm GaN quantum well width and 15nm AlxGa1-xN barrier width. The cutoff wavelength of the MQW photodetectors can be tuned by adjusting the well width and barrier height. Including the polarization field effects, on increasing Al mole fraction, the transition energy decreases, the total noise increases, and the responsivity has a red shift, and so the detectivity decreases and has a red shift.

British Library Electronic Table of Contents (United Kingdom)

A novel liquid phase alkylation of aniline with methanol over Zn/Cu salts modified kaolin assisted with a pair of porous carbon electrode in slurry-bed reactor under constant current intensity, room temperature and atmospheric pressure was reported. The Zn/Cu salts modified kaolin catalysts were synthesized and characterized by infrared spectrometer (IR), powder X-ray diffraction (XRD) and scanning electron microscopy (SEM), which showed that the transition metals were completely supported on kaolins structure and formed a pored one. The effect parameters, such as initial pH, electrolysis time, metal ratio with kaolin and salts composition in this electrochemical catalytic system, were studied. The procedure was inspected by ultraviolet-visible spectrum (UV-vis), and the product distributi...

Energy Technology Data Exchange (ETDEWEB)

Diesel passenger car is superior to gasoline engine car in the fuel economy, but it has some defects to improve: noise, startability, particulate and transient performance, etc. Among these problems, this paper presents particularly transient performance in a diesel engine and clarifies the causes of its decline at lower temperature operation. As the results, it is found that the transient torque at the early stage of acceleration is only 50% at -20/sup 0/C, and that when coolant temperature went up to 20/sup 0/C, the transient torque approaches to that of the warmed up engine. The transient response become worse with retarding the injection timing and with decreasing the engine speed. On the other hand, since the normal response is not obtained despite using high cetane number fuel, main cause of the inferior transient torque is not the poor combustion, but the increase of friction or cooling loss.

Energy Technology Data Exchange (ETDEWEB)

Los Alamos National Laboratory (LANL) and the University of California, San Diego (UCSD) have taken the unprecedented step of creating a collaborative, multi-disciplinary graduate education program and associated research agenda called the Engineering Institute. The mission of the Engineering Institute is to develop a comprehensive approach for conducting LANL mission-driven, multidisciplinary engineering research and to improve recruiting, revitalization, and retention of the current and future staff necessary to support the LANL' s national security responsibilities. The components of the Engineering Institute are (1) a joint LANL/UCSD degree program, (2) joint LANL/UCSD research projects, (3) the Los Alamos Dynamic Summer School, (4) an annual workshop, and (5) industry short courses. This program is a possible model for future industry/government interactions with university partners.

British Library Electronic Table of Contents (United Kingdom)

Gas separation membranes with polydimethylsiloxane(PDMS)/polystyrene(PS) were prepared by using the sequential interpenetrating polymer network (IPN) method with various PS contents (10?70wt%). These gas separation membranes can be applied to reduce the smoke density in the emission gas of diesel engines. PS content has a pronounced effect on the membrane performance. It was found that the optimized PS contents in the final membrane were 50wt%. The emission capacities of diesel engines used in this study were 632 cc and 11,149 cc. When the oxygen separation membrane was used in the diesel engines, the smoke density of both diesel engines was remarkably reduced (35?73%). The oxygen concentration in the inlet air affects the composition of the emission gases. Especially, hydrocarbon (HC) dec...

British Library Electronic Table of Contents (United Kingdom)

The term Process Systems Engineering (PSE) is relatively recent. It was coined about 50 years ago at the outset of the modern era of computer-aided engineering. However, the engineering of processing systems is almost as old as the beginning of the chemical industry, around the first half of the 19th century. Initially, the practice of PSE was qualitative and informal, but as time went on it was formalized in progressively increasing degrees. Today, it is solidly founded on engineering sciences and an array of systems-theoretical methodologies and computer-aided tools. This paper is not a review of the theoretical and methodological contributions by various researchers in the area of PSE. Its primary objective is to provide an overview of the history of PSE, i.e. its origin and evolution; ...

International Nuclear Information System (INIS)

Significant new nuclear-specific software standards have recently been adopted under the sponsorship of the American Nuclear Society and the American Society of Mechanical Engineers. The interest of the US Nuclear Regulatory Commission has also been expressed through their issuance of NUREG/CR-4640. These efforts all indicate a growing awareness of the need for thorough, referenceable expressions of the way to build in and evaluate quality in nuclear software. A broader professional perspective can be seen in the growing number of software engineering standards sponsored by the Institute of Electrical and Electronics Engineers (IEEE) Computer Society. This family of standards represents a systematic effort to capture professional consensus on quality practices throughout the software development life cycle. The only omission-the implementation phase-is treated by accepted American National Standards Institute or de facto ...

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)

Nuclear rocket research and development was initiated in the United States in 1955 and is still being pursued to a limited extent. The major technology emphasis occurred in the decade of the 1960s and was primarily associated with the Rover/NERVA Program where the technology for a nuclear rocket engine system for space application was developed and demonstrated. The NERVA (Nuclear Engine for Rocket Vehicle Application) technology developed twenty years ago provides a comprehensive and viable propulsion technology base that can be applied and will prove to be valuable for application to the NASA Space Exploration Initiative (SEI). This paper, which is historical in scope, provides an overview of the conduct of the NERVA Engine Program, its organization and management, development philosophy, the engine configuration, and significant accomplishments.

Energy Technology Data Exchange (ETDEWEB)

Improvements to a small diesel engine turbocharger were made based on data gathered during a previous Army contract. The improved turbocharger was fabricated and tested on a small, four cylinder, 239 CID diesel engine. Engine dynamometer test data revealed a 2 to 9 percent reduction in fuel consumption at all points over the operating envelope. A turbocharger was operated for 1011 hours at speeds between 70000 and 78000 rpm without incident. The ball bearings were in excellent condition at the end of the test. A math model of the engine and turbocharger was generated. The model was used to estimate 13 Mode Federal Diesel Emissions Cycle, the LA4 driving cycle and the application of the variable area turbine nozzle (VATN) turbocharger to a diesel engine driven generator set. A recommendation was made to build a gen set demo unit. A fuel savings of 8 to 10 percent was estimated for a ...

Energy Technology Data Exchange (ETDEWEB)

This study investigated the engine performance and emissions of a supercharged dual-fuel engine fueled by hydrogen-rich coke oven gas and ignited by a pilot amount of diesel fuel. The engine was tested for use as a cogeneration engine, so power output while maintaining a reasonable thermal efficiency was important. Experiments were carried out at a constant pilot injection pressure and pilot quantity for different fuel-air equivalence ratios and at various injection timings without and with exhaust gas recirculation (EGR). The experimental strategy was to optimize the injection timing to maximize engine power at different fuel-air equivalence ratios without knocking and within the limit of the maximum cylinder pressure. The engine was tested first without EGR condition up to the maximum possible fuel-air equivalence ratio of 0.65. A maximum indicated mean ...

Energy Technology Data Exchange (ETDEWEB)

In 1995, MAN B&W Diesel launched a dual-fuel version of the successful L + V (in-line and vee) configurations of the 32/40 diesel engine series, covering a power range between 2.4 and 7.2 MW. In 1996, the company is launching a dual-fuel version of the L + V 48/60 engine series, moving the power range of dual-fuel engines to 16.2 MW. With its new dual fuel type 32/40 DG and 48/60 DG engines, MAN B&W Diesel has designed prime movers offering a high efficiency at low operating costs, while simultaneously meeting the most stringent NO{sub x} emission limits without any exhaust gas after-treatment. These engines are based on the successful HFO-operated four-stroke diesel engines. They offer environment-friendly and, operating at high mean effective pressures, simultaneously cost effective propulsion alternatives, especially if natural gas is used as a fuel. ...

Energy Technology Data Exchange (ETDEWEB)

The fault detection and diagnosis system for gas engines was developed to improve the reliability of cogeneration systems (CGS). Most of existing fault detection systems monitor the trend of each part condition of engines and diagnose faults based on trend change, resulting in slow detection. Although early detection systems are available, those are complex, expensive and poor in flexibility and applicability. Since CGSs combined with gas engines increased to 1/3 of the whole CGS, engine troubles cause possible serious faults. The fault diagnosis system was thus developed to prevent serious faults which can early detect, in particular, abnormal conditions of parts around a combustion chamber such as ignition plug, intake valve and exhaust valve by monitoring exhaust pressure waveforms in an exhaust collector. Since this system can detect progressive occurrence frequency of abnormal conditions and ...

Energy Technology Data Exchange (ETDEWEB)

The feasibility of using hydrogen as the sole fuel in a direct injection diesel engine was investigated. An air cooled single cylinder Lister ST1 diesel engine was modified to operate as a low-heat-rejection engine for this study. Partially stabilized zirconia ceramic parts were used to shield the combustion space of the engine. Using a compression ratio of 17.9:1 and motoring the test engine at 21000 rpm, a maximum compression temperature of approximately 900 K was achieved. Under these operating conditions, all lubricants tested were found to burn. Lowering the speed to 1450 rpm and the compression ratio to 17.1, lubricant combustion and hot spots were successfully eliminated. The maximum compression temperature, when compression ignition of hydrogen was tried, was in the 800 K range. The corresponding ceramic surface temperature was estimated to reach 600-700 K. Only sporadic ...

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 potential of each engine ...

Energy Technology Data Exchange (ETDEWEB)

A low pressure nuclear thermal rocket (LPNTR) is configured to meet the requirements of a nuclear stage for manned Mars exploration. Safety, reliability and performance are given equal consideration in selecting the stage configuration. Preliminary trade studies are conducted to size the engine thrust and determine the thrust chamber pressure. A weight breakdown and mechanical configuration for the selected LPNTR concept are defined. A seven engine stage configuration is selected which gives a two engine out capability and eliminates the need for engine gimbaling. The stage can be ground assembled and launched as a unit including tankage for trans Earth injection and Earth orbital capture. The tankage is configured to eliminate the need for an inert shield. The small engine will be cheaper to develop than a single engine providing full thrust, and will be ...

International Nuclear Information System (INIS)

In order to follow some of the changes induced by ultraviolet-B (UV-B, 280-320 nm) radiation in Phaseolus vulgaris and Brassica napus, experiments were designed to localize sites of changes in leaves and to correlate some of the physiological and biochemical changes with penetration of UV-B radiation. B.napus was exposed to 8.9 kJ m"-"2 day"-"1 biologically effective UV-B radiation (UV-B_B_E). The penetration of UV-B radiation into the leaf was followed using a quartz fibre optic microprobe. Monochromatic radiation at 310 nm was decreased by ca 50 and 34% in the adaxial and abaxial epidermis, respectively, in plants not exposed to UV-B, whereas the radiation was decreased by ca 70 and 42%, respectively, in the same region in UV-treated plants. Polychromatic radiation showed a wavelength dependent change mainly for the collimated radiation. The results correlated with the distribution of phenolic compounds analysed from 40 #mu#m paradermal leaf sections. The first ...

International Nuclear Information System (INIS)

We describe the growth, fabrication, and characterization of an ultraviolet (UV) photoconductive detector based on In_xAl_yGa_1_-_x_-_yN quaternary alloy that is lattice matched to GaN. The detector consisted of 0.1 #mu#m In_xAl_yGa_1_-_x_-_yN alloy grown on 0.5-1.0 #mu#m GaN epilayer by metalorganic chemical vapor deposition. With varying indium concentration, the cut-off wavelength of the In_xAl_yGa_1_-_x_-_yN detectors could be varied to the deep UV range. The most important and intriguing result is that the responsivity of the In_xAl_yGa_1_-_x_-_yN quaternary alloy exceeded that of AlGaN alloy of a comparable cutoff wavelength by a factor of five. This makes the nitride quaternary alloy very important material for solar blind UV detectors applications particularly in the deep UV range where Al rich AlGaN alloys have problems with low quantum efficiency and cracks due in part to lattice mismatch with GaN. The advantages of In_xAl_yGa_1_-_x_-_yN quaternary over ...

Science.gov (United States)

Scrotal skin of black Long-Evans rats and human thigh skin were maintained in vitro as organ cultures for as long as 14 days, and examined histologically using the combined skin splitting and Dopa techniques. Selected rat skin cultures received testosterone in the culture medium and/or were irradiated with ultraviolet light (290 to 320 nm uvl). With increased time in culture, scrotal melanocytes round up and there is an increase in epidermal pigmentation. Human skin behaves similarly; after eight days in vitro human melanocytes also become rounded, but remain strongly Dopa-positive. Addition of exogenous testosterone to cultured rat skin maintains dendritic morphology of melanocytes, but cell body size is still reduced. uvl irradiation stimulates melanocytes in rat skin cultures, maintaining their dendritic morphology and increasing epidermal and dermal pigmentation. Cultured skin receiving both uvl and testosterone illustrates a synergistic effect. Electron ...

Energy Technology Data Exchange (ETDEWEB)

The Westinghouse Electric Corporation has undertaken to investigate, develop, and characterize laser-assisted processing techniques utilized to produce the fine line, thin metal grid structures that are required to fabricate high-efficiency solar cells. Two basic techniques for metal deposition will be investigated, as follows: (1) photochemical decomposition of liquid or gas phase organometallic compounds utilizing either a focused, CW ultraviolet laser (System 1) or a mask and ultraviolet flood illumination, such as that provided by a repetitively pulsed, defocused excimer laser (System 2), for pattern definition, and (2) thermal deposition of metals from organometallic solutions or vapors utilizing a focused, CW laser beam as a local heat source to draw the metallization pattern. The purpose of this contract is to investigate the various existing laser-assisted film deposition techniques in order to develop a new, cost-effective technology ...

International Nuclear Information System (INIS)

Benzene molecules , present in the proto-planetary nebula CRL 618, are ionized and dissociated by ultraviolet (UV) and X-ray photons originated from the hot central star and by its fast wind. Ionic species and free radicals produced by these processes can lead to the formation of new organic molecules. The aim of this work is to study the photoionization and photodissociation processes of the benzene molecule, using synchrotron radiation and time-of-flight mass spectrometry. Mass spectra were recorded at different energies corresponding to the vacuum UV (21.21 eV) and soft X-ray (282-310 eV) spectral regions. The production of ions from the benzene dissociative photoionization is here quantified, indicating that C_6H_6 is more efficiently fragmented by soft X-ray than UV radiation, where 50% of the ionized benzene molecules survive to UV dissociation while only about 4% resist to C-rays. Partial ion yields of H and small hydrocarbons, such as C_2H_2"+, C_3H_3"+, ...

Energy Technology Data Exchange (ETDEWEB)

This paper deals with the combustion process of the turbocharged dual-fuel engine with regard to improvement to thermal efficiency and exhaust gas emissions. It describes the method of charge-air control used to achieve optimal operation in either a pure diesel engine or a gas engine using the pilot-ignition process (dual-fuel principle). The change-over from gas to diesel operation and vice versa can be made automatically even under full load, i. e. the engine can be changed over from one mode of operation to the other without interruption. The exhaust gas constituents emitted by the dual-fuel engine are less detrimental to the environment than those of other internal-combustion engines: CO is hardly present at all; NOx is no higher than that from good diesel engines, or even lower; SO/sub 2/ does not occur since the natural gas, which is ...