The emission of light charged particles from heavy fragments of uranium fission induced by 153-MeV protons is studied. The probability of their emission is 2.7 x 10{sup - 2} per fission event. It is found that these particles affect the distribution of angles of fragment divergence and the angular distribution of heavy fragments with respect to the primary-proton beam. Experimental results suggest that the preequilibrium emission of particles is correlated with fission. Two mechanisms of interaction between 153-MeV protons and uranium nuclei are considered. 13 refs., 10 figs., 1 tab.
We study the emission zone in a single-layer polymer light-emitting diode. The emission zone is found by studying the angular distribution of the electroluminescence. The emission is modeled by accounting for optical interference. We account for birefringence of the anode layer in our model. The active polymer was, however, found to be isotropic. The anode consists of a single-layer of the conducting polymer complex poly(3,4-ethylenedioxythiophene) and poly(styrene sulfonate) (PEDOT-PSS), with enhanced conductivity. As a cathode we use plain aluminum. By using only PEDOT-PSS we avoid having a thin metal layer or indium-tin-oxide as the anode in the path of the escaping light. The active material is a substituted polythiophene with excellent film forming properties. A comparison between the experimental and calculated angular distribution of light ...
The emission of Cerenkov radiation by tachyons has been examined by using the reduced expansions of superluminal electromagnetic fields in terms of standard helicity representation of Poincare group. It has been shown that the tachyons emit Cerenkov radiation through their coupling only with subluminal electromagnetic fields and that a charged tachyon can emit Cerenkov radiation only in the media in which it travels with a velocity lower than that of light while in the usual medium in which its velocity is more than that of light, it will never emit Cerenkov radiation.
New developments in fluorophores as well as in detection methods have fueled the rapid growth of optical imaging in the life sciences. Commercial widefield microscopes generally use arc lamps, excitation/emission...Full Text Available
The emission of Cerenkov radiation by tachyons has been examined by using the reduced expansions of superluminal electromagnetic fields in terms of standard helicity representation of Poincare group. It has been shown that the tachyons emit Cerenkov radiation through their coupling only with subluminal electromagnetic fields and that a charged tachyon can emit Cerenkov radiation only in the media in which it travels with a velocity lower than that of light while in the usual medium in which its velocity is more than that of light, it will never emit Cerenkov radiation. (author).
Ion Beam Induced Luminescence (IBIL) and Ion Beam Induced Charge Collection (IBICC) have been applied in the study of the luminescence emission efficiency and investigation of the homogeneity of the luminescence emission in phosphors. The IBIL imaging was performed by using sharply focused ion beams or broad/partially-focused ion beams. The luminescence emission homogeneity in samples was examined to reveal possible distributed crystal-defects that may lead to the inhomogeneity of the luminescence emission in samples.The purpose of the study is to search for suitable luminescent thin films that have high homogeneity of luminescence emission, large IBIL efficiency under heavy ion excitation, and can be placed as a thin layer on the top of microelectronic devices to be analyzed with Ion Photon Emission Microscopy (IPEM). The emission yield was ...
Tm3+ and Dy3+ ions co-doped aluminoborosilicate glasses were prepared in this study. The luminescence properties of the glasses were analyzed. A combination of blue, green, yellow, and red emission bands was shown for these glasses, and white lightemission could be observed under UV light excitation. White light luminescence color could be changed by varying the excitation wavelength. Concentration quenching effect was investigated in this paper. Furthermore, the dependence of luminescence properties on glass compositions was studied. Results showed that the luminescence intensity changed with different network modifier oxides, while the white color luminescence was not affected significantly. - Graphical abstract: Tm3+ and Dy3+ ions co-doped aluminoborosilicate glasses, which emit white light under UV light excitation, were prepared. The ...
A high-speed light-Diesel engine with direct injection has been developed by the Institute of Combustion Engines, Graz. Thanks to light construction throughout, exhaust gas supercharger and noise-reduced composition a Diesel engine could be built that is comparable to Otto-cycle engines as regards performance, weight, aggregate size and noise production but far superior to these with respect to fuel consumption and exhaust gas emission.
Photon yields were measured from Cu(110) bombarded by H"+, H_2"+ and He"+ with different energies. The energy dependence is different from previous studies at perpendicular incidence. A calculation of the energy dependence of resonant charge capture into the n=3 state of H is compared with experiment. (G.Q.).
A study was made on the effect of 3.5 MeV electron irradiation on the properties of light-emissive structure based on GaAlAs. It is shown that a considerable decrease in the emitted light intensity as a result of electron irradiation not accompanied by changes in recombination- and electric properties of the mentioned structures. It is established by the electron-microscopy and Auger-spectroscopy meazurements that electron irradiation causes the occurrence of regions of free aluminium clusters on the external surface of the structure n-layer. The number and the sizes of the regions depend on the electron doze. It was assumed that the mentioned regions can play a role of attenuation filter for the light emitted by the structure.
The optical properties of divalent europium activated Ca-#alpha#-SiAlON were investigated and the excitation and emission processes were discussed. The emission wavelength is influenced by the activator concentration of Eu more than the codopant concentration of Ca, in case of the same matrix composition of #alpha#-SiAlON. The red-shift of emission increases when the concentration of Eu increases. In addition, it was revealed that the red-shift of emission would be caused by the construction of the package of optical device. The correlated color temperature becomes low by the red-shift for the white light-emitting diode (LED) lamp using Ca-#alpha#-SiAlON:Eu phosphor when the phosphor powder concentration increases in the transparent resin which coats the primary light source of a blue LED die. The additional red-shift can be observed when the excessive amount of ...
There is a need to reduce air pollutant emissions in some U.S. urban regions to meet federal and state air quality guidelines. Opportunities exist for reducing pollutant emissions from natural gas appliances in the residential sector. A cost-benefit analysis on various pollutant-reducing strategies is needed to evaluate these opportunities. The effectiveness of these pollutant-reducing strategies (e.g., low-emission burners, energy conservation) can then be ranked among themselves and compared with other pollutant-reducing strategies available for the region. A key step towards conducting a cost-benefit analysis is to collect information on pollutant emissions from existing residential natural gas appliances. An extensive literature search was conducted to collect data on residential natural-gas-appliance pollutant emission factors. The literature primarily describes laboratory ...
A finite three-dimensional layer-by-layer photonic crystal with planar defects in a layer is shown to drastically modify the spontaneous emission rate of an embedded dipole. Finite-difference time-domain calculations with one quarter symmetric boundary condition and perfectly matched layer demonstrate the strong enhancement effects induced by the cavity resonance of defect modes and band-edge resonant modes. Simulation shows that the emission spectra are quite different when the position or polarization of the dipole is changed. Moreover, the extraction efficiency is calculated to observe the percentage of light leakage through a substrate.
This paper describes the development and a detailed analysis carried out on the luminescence characteristics of Pr"3"+ doped ZrF_4-BaF_2-LaF_3-YF_3-AlF_3-NaF glasses. In the present work our objectives are to elucidate the possible mechanisms that are responsible for NIR to red upconversion process and yellow to blue upconversion emission in terms of energy level schemes from the praseodymium containing fibre optical glass composition. We have studied their different physical and optical properties. Besides our investigation on the upconversion emission of these glasses, normal fluorescence studies have also been undertaken in explaining the mechanisms in demonstrating bright red and blue emissions upon excitations at visible and UV wavelengths. Besides these measurements works, a bright blue colour emission was observed under an UV source (202 nm) and upconverted prominent red ...
With regard to polybrominated diphenyl ether (PBDE), there is few scientific knowledge on the emission patterns into the environment and exposure pathways to humans, and basic information is insufficient to consider what measures effective are. For the purpose of promoting risk reduction of target substances more effectively and efficiently, it is desirable to comprehend accurately the causal chain from the target substances utilization to the risk intake, and to evaluate the measures covering the whole applications of target substances. As the existing researches on the PBDE emission inventory, there are EU risk assessment report (European Chemical Bureau 2000, 2002, 2003), Danish EPA (1999), Palm et al.(2002) and Alcock et al. (2003). In addition, emissions of DecaBDE are published in TRI (Toxic Release Inventory) of US EPA. However, the primary information of the previous inventories is often the same and estimations ...
The introduction of oxygen in the vicinity of a metallic target surface, bombarded with positive argon ions of twenty kiloelectron-volts, increases the number of sputtered atoms in the excited state. This phenomenon of exaltation, very sensitive in the case of nickel and aluminium, is much less marked in the case of molybdenum. Moreover, the emission of excited particles coming from the beam's ions is not modified. A quantum-mechanical model of a kinetic emission process, which permits the interpretation of the clean metallic target's emission phenomena, seems insufficient to explain all of the results obtained in the presence of oxygen. In this last case one can therfore use a thermodynamic model in which excited metallic particles can be formed directly by chemical surface reactions of neutralization or reduction. (orig.).
The performance of the gaseous fuel supply and its influence on hydrocarbon (HC) emissions of dual-fuel engines have been investigated. A new design of manifold respirators with mixers is also presented in the paper. The design of the gaseous fuel supply system has a great influence on HC emissions in the dual-fuel engine at light load. The problem of scavenging is discussed and solved by using the manifold respirators in the dual-fuel engine. It performs the function of retarding the gaseous fuel entry timing from the moment of intake valve opening, and its delaying effects have been measured and tested. Experimental results show that the manifold respirator gives the best performance in reducing HC emissions compared with a common pipe mixer and a respirator with bo miser. In addition, the mixing effects are sensitive to the mixer configuration. (Author)
Hazardous UV-radiation and short-wavelength visible (blue) light is emitted by the high temperature plasma above the welding-keyhole. Ozone and NO_x is produced due to UV-induced photodissociation of oxygen and high temperature gas-phase reactions. Spectral measurements of the plasma emission show that the allowed dose for UV-radiation and blue light exposure per work day can be exceeded in as short as a few seconds. Similarly, measurements and models of the ozone and NO_x concentration show that the maximum workplace concentrations might be reached quickly if no appropriate exhaust and filter system is installed. (author)
A catalytic trap oxidizer based on a radial flow metal mesh filter was developed for use as an after treatment device on light-duty diesel vehicles. A complete system for assisted regeneration was devised to enable this unit to operate without blocking during all normal driving modes. The integration of the catalyzed trap and regeneration system with the vehicle to provide a practical system for the reduction of diesel particulate emissions is discussed. To date, many prototype catalytic trap and regeneration system installations have been completed on various test vehicles, both naturally aspirated and turbocharged. The operational conditions and test results from a selection of these studies are presented.
In the reaction sup(nat)Ag + /sup 40/Ar (285 MeV) there have been measured the energy spectra of the isotopes of elements from H to Cl at an emission angle of 40/sup 0/, the energy spectra and angular distributions of /sup 1/H, /sup 2/H, /sup 3/H, and /sup 4/He, and the angular distributions of Li, Be, B, and C. The contribution from multinucleon transfer reactions to the formation of light charged particles is discussed.
In this note it is suggested that binuclear platinum(II) complexes with a solely inorganic bridging pyrophosphito ligand also possess many of the complementary advantages of inorganic and organic dyes. They are evaluated for their potential use as a luminescent solar concentrator material. The disadvantages include: the high cost of platinum; the absorption spectra in solution shows a weaker absorption at 452 nm which may cause reabsorption of emitted light; the positions of the absorption and emission maxima are not at the optimal wavelengths for absorption of sunlight and emission to a solar cell. In spite of these drawbacks the author believes the platinum complexes merit consideration for fabrication of solar concentrator devices.
A detailed knowledge about the dynamics of phytoplanktonic photosynthesis and respiration is crucial for the determination of primary productivity in open oceans as well as for biotechnological applications. The dynamics are best studied in photobioreactors that are able to simulate natural conditions in such, that light can be modulated not only diurnally but also mimicking effects of solar elevation angle from sunrise to sunset, variable cloudiness, light modulation in refractory sun flecks due to water waves, or light intermittence due to turbulent flow in dense suspensions. In addition, high performance photobioreactors ought to be able to monitor in real time photosynthetic and respiratory activities as well as culture growth. Here, we demonstrate performance of a newly designed bench...
A multi-zone computational model in conjunction with some engine tests are used to examine the combustion process of gas fueled diesel engines common known as dual fuel engine to provide information about details of the production of exhaust emissions, especially at light load when very lean mixtures are employed. Detailed chemical reaction kinetic simulation is employed for each of these individual combustion zones so as to establish the associated temporal variations in the concentrations of reacting species right to the exhaust stage. The influence of changes in major operating and design parameters such as the concentration of the gaseous fuel in the cylinder charge, intake temperature and the size of the diesel pilot fuel employed on the production of the exhaust emissions are examined. It is demonstrated in general that any measure that tends to increase the size of the combustion regions within the overly lean ...
A multi-zone computational model in conjunction with some engine tests are used to examine the combustion process of gas fueled diesel engines commonly known as dual fuel engine to provide information about details of the production of exhaust emissions, especially at light load when very lean mixtures are employed. Detailed chemical reaction kinetic simulation is employed for each of these individual combustion zones so as to establish the associated temporal variations in the concentrations of reacting species right to the exhaust stage. The influence of changes in major operating and design parameters such as the concentration of the gaseous fuel in the cylinder charge, intake temperature and the size of the diesel pilot fuel employed on the production of the exhaust emissions are examined. It is demonstrated in general that any measure that tends to increase the size of the combustion regions within the overly lean ...
Primordial black holes are unique probes of cosmology, general relativity, quantum gravity and non standard particle physics. They can be considered as the ultimate particle accelerator in their last (explosive) moments since they are supposed to reach, very briefly, the Planck temperature. Upper limits on the primordial black hole number density of mass $M_{\\star} = 5 10^{14}$ g, the Hawking mass (born in the big-bang terminating their life presently), is determined comparing their predicted cumulative $\\gamma$-ray emission, galaxy-wise, to the one observed by the EGRET satellite, once corrected for non thermal $\\gamma$-ray background emission induced by cosmic ray protons and electrons interacting with light and matter in the Milky Way. A model with free gas emissivities is used to map the Galaxy in the 100 MeV photon range, where the peak of the primordial black hole emission ...
Ultra-luminous infrared galaxies are among the most luminous objects in the local universe and are thought to be powered by intense star formation. It has been shown that in these objects the rotational spectral lines of molecular hydrogen observed at mid-infrared wavelengths are not affected by dust obscuration, leaving unresolved the source of excitation of this emission. Here I report an analysis of archival Spitzer Space Telescope data on ultra-luminous infrared galaxies and demonstrate that star formation regions are buried inside optically thick clouds of gas and dust, so that dust obscuration affects star-formation indicators but not molecular hydrogen. I thereby establish that the emission of H_2 is not co-spatial with the buried starburst activity and originates outside the obscured regions. This is rather surprising in light of the standard view that H_2 emission is directly associated with ...
An analytic solution is obtained for the equations of resonance coherent SRS by neglecting the population of the final level of the Raman transition for the systems with the active-medium length that is smaller than the wavelength of the incident light. For the extended systems, a numerical solution is obtained. The energy distribution of the Stokes pulses is found. The large-scale (about 100%) fluctuations of the Stokes radiation energy were observed in the case of unsaturated amplified spontaneous emission. (nonlinear optical phenomena)
...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 - ...
The authors summarize EUVE's contribution to the study of the boundary layer emission of high accretion-rate nonmagnetic cataclysmic variables, especially the dwarf novae SS Cyg, U Gem, VW Hyi, and OY Car in outburst. They discuss the optical and EUV light curves of dwarf nova outbursts, the quasi-coherent oscillations of the EUV flux of SS Cyg, the EUV spectra of dwarf novae, and the future of EUV observations of cataclysmic variables.
The necessary conditions to design the methanol-fueled direct injection diesel engine with a reservoir type glow plug were cleared up from the points of view to prevent the air contamination and to use as an alternative oil for automotives, and as a result the good engine performance and emission characteristics could be obtained under the wide operating condition. The following facts were clarified: It is necessary to arrange the glow plug on the line of atomizing axis near the nozzle hole to ensure the ignitability under a wide operating condition. The reservoir type glow plug which reserves the premixed gas around the glow plug can shorten the ignition delay time and improve the combustion stability and the net thermal efficiency in the light load region. The combustion in the light load region was accelerated, NO{sub x} emission rate was suppressed and moreover, the net thermal efficiency and ...
Cerium is known to enter substitutionally in trivalent state when doped in alkali halides. Cerium doped NaCl crystals exhibit greatly enhanced thermoluminescence output upon X-irradiation at RT, the intensity of emission being about 10 times that in undoped crystals for similar dosage of irradiation. The cerium doped crystals give upon X-irradiation a very intense glow peak at 145degC with shoulders at 120degC and 210degC. Upon partially bleaching the crystal with F-light, the peak at 120degC becomes prominent probably due to faster bleaching of the glow at 145degC. From further optical bleaching studies, it is concluded that the glow peak at around 120degC is due to cerium centres in the irradiated crystal and the 145degC peak due to F centres. This F centre emission occurs at lower temperature, compared to that in the undoped crystals where it occurs at around 180degC. The spectral emission in the Ce ...
Neutrino emission drives neutron star cooling for the first several hundreds of years after its birth. Given the low energy ($\\sim$ keV) nature of this process, one expects very few nonstandard particle physics contributions which could affect this rate. Requiring that any new physics contributions involve light degrees of freedom, one of the likely candidates which can affect the cooling process would be a nonzero magnetic moment for the neutrino. To illustrate, we compute the emission rate for neutrino pair bremsstrahlung in neutron-neutron scattering through photon-neutrino magnetic moment coupling. We also present analogous differential rates for neutrino scattering off nucleons and electrons that determine neutrino opacities in supernovae. Employing current upper bounds from collider experiments on the tau magnetic moment, we find that the neutrino emission rate can exceed the rate through neutral ...
A method for quick, high-accuracy measurement of lithium isotopes has become necessary in carrying out research on the separation and concentration of lithium isotopes by ion exchange. The present report focuses on the application of a hollow cathode, as excitation source, to emission spectral analysis for lithium isotope measurement. The grating monochromator used incorporates a pressure scanned etalon. With decreased Doppler broadening and pressure broadening, the hollow cathode, used as excitation source, can give narrow spectral lines, permitting good separation among them. To achieve a high accuracy, the emission intensity of the hollow cathode should be maintained as stable as possible relative to time. In particular, the stability of a light source can be affected significantly by the chemical form of the sample. A study is also made here to identify a condition where lithium acetate effluent as-obtained from an ion ...
Diesel engines operating on gaseous fuels are commonly known as dual-fuel engines. In the present work, a single-cylinder, compression ignition, indirect injection research (Ricardo E6) engine has been installed at United Arab Emirates University for investigation of the exhaust emissions when the engine is operating as a dual-fuel engine. The influence of changes in major operating and design parameters, such as the concentration of gaseous fuel in the cylinder charge, pilot fuel quantity, injection timing and intake temperature, on the production of exhaust emissions was investigated. Diesel fuel was used as the pilot fuel, while methane or propane was used as the main fuel which was inducted in the intake manifold and mixed with the intake air. The experimental investigations showed that the poor emissions at light loads can be improved significantly by increasing the concentration of gaseous fuel ...
We report the detection of X-ray pulsations with a period of ?315.87 ms from the 2009 XMM-Newton observation for the radio-quiet ?-ray pulsar, LAT PSR J0007+7303, centered in the supernova remnant CTA 1. The detected pulsed period is consistent with the ?-ray periodicity at the same epoch found with the Fermi Gamma-ray Space Telescope. The broader sinusoidal structure in the folded light curve of the X-ray emission is dissimilar to that of the ?-ray emission, and the phase of the peak is about 0.5 shifting from the peak in the ?-ray bands, indicating that the main component of the X-rays originates from different sites of the pulsar. We conclude that the main component of the X-ray pulsation is contributed by the thermal emission from the neutron star. Although with a significantly different characteristic age, PSR J0007+7303 is similar to Geminga in emission properties of X-rays ...
Single-phased Sr3B2SiO8:Eu3+ phosphor was prepared by a solid-state method at 1020 oC. The luminescence spectra showed that Sr3B2SiO8:Eu3+ phosphor can be effectively excited by near ultraviolet light (393 nm) and blue light (464 nm). When excited at 393 or 464 nm Sr3B2SiO8:Eu3+ exhibited the main emission peaks at 611 and 620 nm, which resulted from the supersensitive 5D0#->#7F2 transition of Eu3+. The luminescence intensity of Sr3B2SiO8:Eu3+ at 611 and 620 nm reached the maximum when the doping content of Eu3+ was 4.5 mol%. Its chromaticity coordinates (0.646, 0.354) were very close to the NTSC standard values (0.67, 0.33). Thus, Sr3B2SiO8:Eu3+ is considered to be an efficient red-emitting phosphor for long-UV InGaN-based light-emitting diodes. - Highlights: ? Sr3B2SiO8:Eu3+ was synthesized using solid-state reaction method for the first time. ? The phosphor can be efficiently excited by the ...
The combination of functional and morphological imaging technologies such as positron emission tomography (PET) and X-ray computed tomography (CT) has shown its value in the clinical and preclinical field. However, CT provides only very limited soft-tissue contrast and exposes the examined patient or laboratory animal to a high X-ray radiation dose. In comparison to CT, magnetic resonance tomography (MRI) provides excellent soft-tissue contrast and allows for nuclear magnetic resonance spectroscopy (NMRS) or functional MRI (fMRI). Thus, the combination of PET and MRI has been pursued for several years. First approaches have succeeded using conventional photo multiplier tube (PMT) technology together with light fibers to transfer scintillation light away from the high magnetic field. Latest...
In light of the global focus on greenhouse gas emissions, energy consumption of communication networks has become an important research area. Networks are major energy consumers and are generally dimensioned for peak loads. For extended periods, resources consume power, but are lightly or unused. This research investigates the concept of dynamic topologies, i.e. networks that adapt their topology according to traffic volume. The key aim of this study is to investigate power reductions that can be achieved by dynamic topologies. It proposes a network transformation and introduces mathematical programming models that results in energy optimal topologies for given traffic loads. This paper focuses on the optimisation problems and investigates gains in static environments. Numerical results ar...
Results from the asymmetric reactions 80 and 100 MeV/uLa + C are presented and compared to earlier work with the same system at 18 and 50 MeV/u. Fragment-fragment correlations, cross sections, and distributions in velocity space indicate the continued dominance of a quasi-binary decay mechanism with increased emission of light charged particles. The distributions in velocity also indicate a progression toward a ''fireball'' type of reaction mechanism. However, the angular distributions of the emitted fragments are incompatible with statistical production mechanisms that have successfully explained the lower energy results, and indicate the dynamical nature of the emission process. Dalitz plots of triple complex fragment coincidences are presented in order to investigate the nature of the multibody decays. 18 refs., 9 figs.
We have measured some of the optical characteristics of a novel energy conversion medium, over a range of compositions in the system Yb[sub 2]O[sub 3][minus]Al[sub 2]O[sub 3], which we have fabricated by a proprietary process. These specimens have good resistance to thermal shock, are durable, and are mechanically and chemically stable. The integrated emission of light generated by these unoptimized specimens when heated with a propane-air flame and detected with a silicon photodetector ranged up to 1.88 watts/cm[sup 2]. The emission spectrum from these specimens when heated with a propane-air flame and detected with a germanium photodetector shows a narrow band in the vicinity of 1 micron.
The optical emission of excited H reflected from clean Cu(110) after impingement of H/sup +/ and H/sub 2//sup +/ in the energy range of 250 eV to 20 keV per nucleon at 70/sup 0/ angle of incidence to the surface normal was measured. For incident 10 keV H/sub 2//sup +/, the highest excited hydrogen state detected was the n=10 level. The Hsub(..cap alpha..) yield was found to be fluence and energy dependent. This effect is attributed either to fast sputtered hydrogen, surface roughness or to an increase with hydrogen concentration in electron states of p-like symmetry near the Fermi level of copper. The Hsub(..cap alpha..) yield per reflected nucleon shows approximately an exponential dependence on both projectile energy per nucleon and scattered particle reciprocal velocity perpendicular to the surface.
The optical emission of excited H reflected from clean Cu(110) after impingement of H"+ and H_2"+ in the energy range of 250 eV to 20 keV per nucleon at 70"0 angle of incidence to the surface normal was measured. For incident 10 keV H_2"+, the highest excited hydrogen state detected was the n=10 level. The Hsub(#alpha#) yield was found to be fluence and energy dependent. This effect is attributed either to fast sputtered hydrogen, surface roughness or to an increase with hydrogen concentration in electron states of p-like symmetry near the Fermi level of copper. The Hsub(#alpha#) yield per reflected nucleon shows approximately an exponential dependence on both projectile energy per nucleon and scattered particle reciprocal velocity perpendicular to the surface. (orig.).
The intrinsic fluorescence of clear amniotic fluid from third-trimester pregnancy is reported. The fluorescence intensity peaked at 405 nm when excited by ultraviolet light in the range of 310 to 360 nm. All of the 33 samples tested fluoresced, and their emission spectrum had the same shape, varying only in magnitude. Changing sample temperature (20 to 50 C) and sample pH (7.2 to 7.7) had little effect on the emission spectrum. The same fluorescence, with higher intensity, was observed when some newborn urine was tested. The fluorescence of amniotic fluid may provide a new tool to determine fetal age, fetal organ maturation, and fetal distress. (author).
Proton induced X-ray emission (PIXE) and proton induced {gamma}-ray emission (PIGE) techniques are employed for the determination of essential and trace elements in some commonly used medicinal plants of north east India. Light elements such as Na, Mg, Al and P are determined by PIGE while medium Z elements such as K, Ca, Mn, Fe, Cu, Zn, Rb and Sr are determined by PIXE. Analysis is performed on pellets (thick targets) prepared using powders of the specimens which, in turn, are obtained following a series of processing steps. Plant based biological certified reference materials (CRMs) served as standards for quantification. These elements are found to be present in varying concentrations in the studied plants, with the contents of Mn and Zn being notably large in certain specimens. Medicinal properties possessed by these plants have been correlated with their elemental distribution.
This paper describes the development and a detailed analysis carried out on the luminescence characteristics of Pr{sup 3+} doped ZrF{sub 4}-BaF{sub 2}-LaF{sub 3}-YF{sub 3}-AlF{sub 3}-NaF glasses. In the present work our objectives are to elucidate the possible mechanisms that are responsible for NIR to red upconversion process and yellow to blue upconversion emission in terms of energy level schemes from the praseodymium containing fibre optical glass composition. We have studied their different physical and optical properties. Besides our investigation on the upconversion emission of these glasses, normal fluorescence studies have also been undertaken in explaining the mechanisms in demonstrating bright red and blue emissions upon excitations at visible and UV wavelengths. Besides these measurements works, a bright blue colour emission was observed under an UV source (202 nm) and upconverted prominent ...
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 ...
Various compositions of Y(Ta,Nb)O4:Eu3+,Tb3+ with different Nb and activator concentrations have been investigated under UV and VUV excitation. Some compounds with very strong emission under VUV excitation were found. Such phosphors could be proposed as very good emissive materials for Displays and Lightings. The growing interest in luminescence spectroscopy of rare earth ions in the vacuum ultraviolet (VUV) and the visible (VIS) spectral range is due to industrial demands for new applications. YTaO4 and YNbO4 phosphors are a perspective class of efficient materials that are generally used in X-ray intensifying screens. These phosphors exhibit satisfying luminescence whenever excited by UV light, cathode radiation or X ray. However, to our knowledge, no work has been published on the VUV-excited luminescence for Eu3+ and Tb3+ double activated yttrium niobate and yttrium tantalate based phosphors. In ...
Light duty vehicles, i.e. passenger cars and light trucks, account for approximately half of global transportation energy demand and, thus, a major share of carbon dioxide and other emissions from the transport sector. Energy consumption in the transport sector is expected to grow in the future, especially in developing countries. Cars with alternative powertrains to internal combustion engines (notably battery, hybrid and fuel-cell powertrains), in combination with potentially low carbon electricity or alternative fuels (notably hydrogen and methanol), can reduce energy demand by at least 50%, and carbon dioxide and regulated emissions much further. This article presents a comparative technical and economic assessment of promising future fuel/vehicle combinations. There are several promising technologies but no obvious winners. However, the electric drivetrain is a common denominator in the alternative ...
The scattering and recombination processes between two triplet excitons in conjugated polymers are investigated by using a nonadiabatic evolution method, based on an extended Su-Schrieffer-Heeger model including interchain interactions. Due to the interchain coupling, the electron and/or hole in the two triplet excitons can exchange. The results show that the recombination induces the formation of singlet excitons, excited polarons and biexcitons. Moreover, we also find the yields of these products, which can contribute to the emission, increase with the interchain coupling strength, in good agreement with results from experiments.
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.
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.
Elemental substitution of Ca by Y was investigated for Ca-#alpha#-SiAlON:Eu yellow phosphors, which is useful for the white light-emitting diode lamps of phosphor conversion type. Depending on the ratio of the elemental substitution, not only the red shift of emission in wavelength occurred but also the figure of the excitation spectra changed. Their excitation band widths and flatness were discussed. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)
Coherent x-ray production by a seeded free electron laser (FEL) is important for next generation synchrotron light sources. The authors examine the feasibility and features of FEL emission seeded by a high-order harmonic generation (HHG) of an infrared laser. In addition to the intrinsic FEL chirp, the longitudinal profile and spectral bandwidth of the HHG seed are modified significantly by the FEL interaction well before saturation. This smears out the original attosecond pulselet structure. The authors introduce criteria for this smearing effect on the pulselet and the stretching effect on the entire pulse. They discuss the noise issue in such a seeded FEL.
This study demonstrates amplified spontaneous emission (ASE) of the ultraviolet (UV) electroluminescence (EL) from ZnO at #lambda##approx#380 nm in the n-ZnO/ZnO nanodots-SiO_2 composite/p- Al_0_._1_2Ga_0_._8_8N heterojunction light-emitting diode. A SiO_2 layer embedded with ZnO nanodots was prepared on the p-type Al_0_._1_2Ga_0_._8_8N using spin-on coating of SiO_2 nanoparticles followed by atomic layer deposition (ALD) of ZnO. An n-type Al-doped ZnO layer was deposited upon the ZnO nanodots-SiO_2 composite layer also by the ALD technique. High-resolution transmission electron microscopy (HRTEM) reveals that the ZnO nanodots embedded in the SiO_2 matrix have diameters of 3-8 nm and the wurtzite crystal structure, which allows the transport of carriers through the thick ZnO nanodots-SiO_2 composite layer. The high quality of the n-ZnO layer was manifested by the well crystallized lattice image in the HRTEM picture and the low-threshold ...
light-emitting diode A light-emitting diode, or LED, is a semi-conductor light source that emits visible light or invisible infrared radiation. Semi-conductors ...
We demonstrate that fitted values of stellar radius obtained by fitting theoretical light curves to observations of millisecond period X-ray pulsars can significantly depend on the method used to calculate the light curves. The worst-case errors in the fitted radius are evaluated by restricting ourselves to the case of light emitted and received in the equatorial plane of a rapidly-rotating neutron star. First, using an approximate flux which is adapted to the one-dimensional nature of such an emission region, we show how pulse shapes can be constructed using an exact spacetime metric and fully accounting for time-delay effects. We compare this to a method which approximates the exterior spacetime of the star by the Schwarzschild metric, inserts special relativistic effects by hand, and neglects time-delay effects. By comparing these methods, we show that there are significant differences in these ...
The combination of functional and morphological imaging technologies such as positron emission tomography (PET) and X-ray computed tomography (CT) has shown its value in the clinical and preclinical field. However, CT provides only very limited soft-tissue contrast and exposes the examined patient or laboratory animal to a high X-ray radiation dose. In comparison to CT, magnetic resonance tomography (MRI) provides excellent soft-tissue contrast and allows for nuclear magnetic resonance spectroscopy (NMRS) or functional MRI (fMRI). Thus, the combination of PET and MRI has been pursued for several years. First approaches have succeeded using conventional photo multiplier tube (PMT) technology together with light fibers to transfer scintillation light away from the high magnetic field. Latest PET/MRI developments use solid-state light detectors that can be operated even at high magnetic fields. Initial ...
Some models for quantum gravity (QG) violate Lorentz invariance and predict an energy dependence of the speed of light, leading to a dispersion of high-energy gamma-ray signals that travel over cosmological distances. Limits on the dispersion from short-duration substructures observed in gamma-rays emitted by gamma-ray bursts (GRBs) at cosmological distances have provided interesting bounds on Lorentz invariance violation (LIV). Recent observations of unprecedentedly fast flares in the very-high energy gamma-ray emission of the active galactic nuclei (AGNs) Mkn 501 in 2005 and PKS 2155-304 in 2006 resulted in the most constraining limits on LIV from light-travel observations, approaching the Planck mass scale, at which QG effects are assumed to become important. I review the current status of LIV searches using GRBs and AGN flare events, and discuss limitations of light-travel time analyses and ...
There is renewed interest in the development of natural gas vehicles in response to the challenge to reduce urban air pollution and consumption of petroleum. The natural gas/diesel dual fuel engine is one way to apply natural gas to the conventional diesel engine. Dual fuel engines operating on natural gas and diesel emit less nitrogen oxides, and less carbon soot to the air compared to conventional diesel engines. The problem is that at light loads, fuel efficiency is reduced and emissions of hydrocarbons and carbon monoxide are increased. This thesis focused on control methods for emissions of hydrocarbons and carbon monoxide in the dual fuel engine at light loads. This was done by developing a reverse flow catalytic converter to complement dual fuel engine exhaust characteristics. Experimental measurements and numerical simulations of reverse flow catalytic converters were conducted. Reverse flow ...
The objective of this 3.5 year project is to develop a commercially competitive vehicle powered by ethanol (or ethanol blend) that can meet California`s ultra-low emission vehicle (ULEV) standards and equivalent corporate average fuel economy (CAFE) energy efficiency for a light-duty passenger car application. The definition of commercially competitive is independent of fuel cost, but does include technical requirements for competitive power, performance, refueling times, vehicle range, driveability, fuel handling safety, and overall emissions performance. This report summarizes a system design study completed after six months of effort on this project. The design study resulted in recommendations for ethanol-fuel blends that shall be tested for engine low-temperature cold-start performance and other criteria. The study also describes three changes to the engine, and two other changes to the vehicle to improve ...
The article presents the comparative bench testing results of a naturally aspirated four stroke, four cylinder, water cooled, direct injection Diesel engine when running on shale oil that has been treated with multi-functional fuel additives. The purpose of the research is to evaluate the effectiveness of the fuel additives Marisol FT (Sweden) and SO-2E (Estonia) as well as to verify their ability to increase energy conversion and reduce brake specific fuel consumption, contamination and smoke opacity of the exhausts when fuelling the Diesel engine with shale oil. Test results show that application of these additives could be a very efficient means to improve diesel engine performance on shale oil, especially when operating at the light load range. The brake specific fuel consumption at light loads and speeds of 1400-2000 min{sup -1} reduces by 18.3-11.0% due to the application of the Marisol FT. The additive SO-2E proves to produce nearly the ...
An experimental study was performed to provide the combustion and emission characteristics resulting from fuel-reactivity controlled compression ignition (RCCI) combustion mode utilizing dual-fuel approach in a light-duty, multi-cylinder diesel engine. In-cylinder fuel blending using port fuel injection of gasoline before intake valve opening (IVO) and early-cycle, direct injection of diesel fuel was used as the charge preparation and fuel blending strategy. In order to achieve the desired auto-ignition quality through the stratification of the fuel-air equivalence ratio ( ), blends of commercially available gasoline and diesel fuel were used. Engine experiments were performed at an engine speed of 2300rpm and an engine load of 4.3bar brake mean effective pressure (BMEP). It was found that significant reduction in both nitrogen oxide (NOx) and particulate matter (PM) was realized successfully through the RCCI combustion mode even without ...
Previous work has shown the Orion Bar to be an interface between ionized and molecular gas, viewed roughly edge on, which is excited by the light from the Trapezium cluster. Much of the emission from any star-forming region will originate from such interfaces, so the Bar serves as a foundation test of any emission model. Here we combine X-ray, optical, IR and radio data sets to derive emission spectra along the transition from H+ to H0 to H2 regions. We then reproduce the spectra of these layers with a simulation that simultaneously accounts for the detailed microphysics of the gas, the grains, and molecules, especially H2 and CO. The magnetic field, observed to be the dominant pressure in another region of the Orion Nebula, is treated as a free parameter, along with the density of cosmic rays. Our model successfully accounts for the optical, IR and radio observations across the Bar by including a ...
Abstract Visible blue cathodoluminescence (CL), photoluminescence (PL), x-ray excited optical luminescence (XEOL) and electroluminescence (EL) via Zf free excitonic emission have been obtained from CuBr thin films deposited on glass, Cr coated glass, GaAs and Si substrates. In addition to the Zf emission several peaks corresponding to Cu+ emissions via 3d94s - d10 transitions were observed on the AC EL spectrum at 2.10, 2.7, 3.03, 3.07 and 3.80 eV. X-ray diffraction (XRD) measurements confirmed that the vacuum evaporated CuBr thin films grow preferentially with a (111) orientation irrespective of the substrate. While the AC voltage source was found to have no detrimental effects on CuBr thin films, cathodic deposition of Cu metal via electrolytic decomposition was observed under steady sta...
This report documents the development and use of the Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model. The model, developed in a spreadsheet format, estimates the full fuel- cycle emissions and energy use associated with various transportation fuels for light-duty vehicles. The model calculates fuel-cycle emissions of five criteria pollutants (volatile organic compounds, carbon monoxide, nitrogen oxides, sulfur oxides, and particulate matter measuring 10 microns or less) and three greenhouse gases (carbon dioxide, methane, and nitrous oxide). The model also calculates the total fuel-cycle energy consumption, fossil fuel consumption, and petroleum consumption using various transportation fuels. The GREET model includes 17 fuel cycles: petroleum to conventional gasoline, reformulated gasoline, clean diesel, liquefied petroleum gas, and electricity via residual oil; ...
This document is the final report for Cooperative Agreement DE-FC26-04NT42314, 'Kinetics Study of Mercury Reactions in FGD Liquors'. The project was co-funded by the U.S. DOE National Energy Technology Laboratory and EPRI. The objective of the project has been to determine the mechanisms and kinetics of the aqueous reactions of mercury absorbed by wet flue gas desulfurization (FGD) systems, and develop a kinetics model to predict mercury reactions in wet FGD systems. The model may be used to determine optimum wet FGD design and operating conditions to maximize mercury capture in wet FGD systems. Initially, a series of bench-top, liquid-phase reactor tests were conducted and mercury species concentrations were measured by UV/visible light spectroscopy to determine reactant and byproduct concentrations over time. Other measurement methods, such as atomic absorption, were used to measure concentrations of vapor-phase elemental mercury, that cannot be ...
Proton and alpha particle spectral shapes and multiplicities have been measured in coincidence with evaporation residues from {sup 28}Si+{sup 165}Ho and {sup 16}O + {sup 197}Au, {sup 208}Pb fusion reactions. Our experiments used 145 to 220 MeV {sup 28}Si and 115 and 140 MeV {sup 16}O beams produced with the Stony Brook LINAC. ER`s were separated using an electrostatic deflector and detected with large area surface barrier detectors. Light charged particles were detected at forward and backward angles with fourteen single NaI detectors. In the context of the statistical model, charged particle spectra yield information about emission barriers and compound nucleus equilibrium level densities. These are significant ingredients in calculations determining fission timescales from other observables such as pre-scission neutron multiplicities or fusion-evaporation excitation functions. Results will also be compared to analyses of pre-scission charged ...
High spin states of the proton rich nuclei in the mass region A {approx} 100 have been studied at the GASP spectrometer through the evaporation of light charged particles and heavier ions detected in the 4{pi} Si-ball Isis. Rear side injection and pulse shape analysis have allowed a good discrimination among protons, alpha particles and heavy ions up to C. Of the several nuclei populated in the reactions we will discuss here the high spin states of {sup 105} Sn. In addition to an extension of the spherical level, scheme, a regular sequence of dipole transitions has been found, The states of the dipole band are suggested to be built on a neutron h{sup 2}{sub 11/2} excitation coupled to proton particle-hole states, which polarize the core to a slightly prolate shape. The experimental results are in agreement with the prediction of tilted axis cranking calculations, which satisfactorily explain the properties of the band. (author) 17 refs., 4 figs.
4,4'-bis(N-carbazolyl)tolan (BCT) and 4,4'-bis[N-(3,6-di-t-butyl)carbazolyl]tolan (BCT-t-Bu) were synthesized as ?-expanded analogs of 4,4'-bis(N-carbazolyl)biphenyl. Their photophysical characteristics both in solution and films were thoroughly investigated. Interestingly, the phosphorescence spectrum of BCT was significantly medium-dependent, and the emission maximum was red-shifted by 131 nm from 489 nm in solution at 77 K to 620 nm in a deposited film at 5 K, suggesting the presence of strong intermolecular interactions in the film. BCT and BCT-t-Bu were found to be useful as host materials for fluorescence-based organic light emitting diodes (OLEDs). However, their low triplet energy levels in films negated their potential to act as hosts in phosphorescence-based OLEDs. - Research highlights: ? We synthesized N-carbazolyl-tolan derivatives (BCT) as ?-expanded analogues of CBP. ? We found that BCT derivatives are useful as host materials ...
Optically stimulated luminescence (OSL) and thermoluminescence are observed in polycrystalline RbMgF3:Eu2+ after x-ray, ?-ray, or ? irradiation. The main electron traps are F-centers but there are other unidentified traps. The main hole traps at room temperature are probably Eu3+ and thermal or optical stimulation leads to electron-hole recombination at the Eu3+ site and Eu2+ emissions arising from 6PJ to 8S7/2 and 4f5d(Eg) to 8S7/2 transitions. We find that some of the electron traps can be emptied by infrared stimulation and all of the electron traps can be emptied by white light stimulation. The OSL dark decay is long and exceeds 5 days for traps that are emptied by white light stimulation after initial infrared bleaching. Our results show that this compound can be used as a radiation dosimeter for intermediate dose levels where the 87Rb self-dose does not significantly affect the dose reading.
A brief comparative review of possible mercury free fluorescent lighting technologies is presented, including rare-gas positive column discharges, molecular discharges, and dielectric barrier discharges. Detailed experimental results on xenon positive column discharges will then be considered. In order to judge whether xenon-based discharges are a viable UV source it is necessary to measure the radiant emittance (power per unit area) for the vacuum ultraviolet (VUV) resonance xenon emission at 147 nm. Two techniques to determine the VUV radiant emittance have been developed and applied to xenon discharges. One method combines the measured resonance level density using absorption spectroscopy and a calculation of the trapped decay rate for the resonance radiation to arrive at the radiant emittance at 147 nm. A second method utilizes a direct measurement of the radiance (power per unit area per unit solid angle) at 147 nm using a calibrated VUV ...
Metabolic engineering of photosynthetic organisms is required for utilization of light energy and for reducing carbon emissions.Control of transcriptional regulators is a powerful approach for changing cellular dynamics, because a set of genes is concomitantly regulated. Here, we show that overexpression of a group 2 ? factor, SigE, enhances the expressions of sugar catabolic genes in the unicellular cyanobacterium, Synechocystis sp. PCC 6803. Transcriptome analysis revealed that genes for the oxidative pentose phosphate pathway and glycogen catabolism are induced by overproduction of SigE. Immunoblotting showed that protein levels of sugar catabolic enzymes, such as glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase, glycogen phosphorylase, and isoamylase, are increased. Glycogen levels are reduced in the SigE-overexpressing strain grown under light. Metabolome analysis revealed that metabolite levels of ...
We present an approach for fabrication of intentionally positioned epitaxial InAs QDs in a micron sized light emitting diode. For site-selective growth, a combination of molecular beam epitaxy (MBE) and focused ion beam (FIB) implantation technology in an all-ultra-high-vacuum (UHV) setup has been employed. Single dot occupancy of almost 55 % on FIB patterned nano-depressions was successfully achieved. Thereafter, carrier injection and subsequent radiative recombination from the positioned InAs/GaAs self-assembled QDs was investigated by embedding these QDs in the intrinsic part of a GaAs-based micron sized p-i-n junction device. Few or single dot are expected to be electrically addressed in these devices. We report results from electroluminescence (EL) measurement which proves the single dot characteristics of our device. The EL spectra consist of sharp emission lines and their dependence on injection current shows linear behavior for exciton ...
We develop and demonstrate the methodology of testing multi-dimensional supernova models against observations by studying the properties of one example of the detonation from failed deflagration (DFD) explosion model of thermonuclear supernovae. Using time-dependent multi-dimensional radiative transfer calculations, we generate the synthetic broadband optical light curves, near-infrared light curves, color evolution curves, full spectral time-series, and spectropolarization of the model, as seen from various viewing angles. All model observables are critically evaluated against examples of well-observed, standard Type Ia supernovae (SNe Ia). We explore the consequences of the intrinsic model asphericity by studying the dependence of the model emission on viewing angle, and by quantifying the resulting dispersion in (and internal correlations between) various model observables. These statistical properties of the model are ...
An in situ synthesis of ZnS and CdS quantum dots (QDs) in an aqueous solution of sodium hyaluronate (Hyal) produced foils emitting light on excitation with a UV light. The wavelength of emission was only slightly QDs size and more QDs concentration dependent and reached up to {approx}320 nm in the case of ZnS and {approx}400-450 nm in the case of CdS. Nanoparticles remained as non-agglomerated 10-20 nm nanoclusters. CdS/Hyal and ZnS/Hyal-QDs biocomposites were characterized using photoluminescence (PL), IR spectrometric techniques, and Transmission Electron Microscopy (TEM). The absolute molecular weights, radii of gyration, R{sub g}, and thermodynamic properties of the obtained foils are given. Electric resistivity studies performed for the hyaluronic foil in the 100-1000 V range have revealed that the hyaluronate foil has very weak conducting properties and QDs only insignificantly affect those properties as QDs ...
We study the high-energy emission of the Galactic black hole candidate GX 339-4 using INTEGRAL/SPI and simultaneous RXTE/PCA data. By the end of January 2007, when it reached its peak luminosity in hard X-rays, the source was in a bright hard state. The SPI data from this period show a good signal to noise ratio, allowing a detailed study of the spectral energy distribution up to several hundred keV. As a main result, we report on the detection of a variable hard spectral feature (>150 keV) which represents a significant excess with respect to the cutoff power law shape of the spectrum. The SPI data suggest that the intensity of this feature is positively correlated with the 25 - 50 keV luminosity of the source and the associated variability time scale is shorter than 7 hours. The simultaneous PCA data, however, show no significant change in the spectral shape, indicating that the source is not undergoing a canonical state transition. We analyzed the broad band ...
The traveling-wave mode in ring lasers is achieved by two methods: by a reversing mirror, and by using an intracavity nonreciprocal device. This paper is devoted to realization of the traveling-wave mode in a mode-locked YAG-Nd ring laser by a method proposed by Tomov et al. This method uses two intracavity Q-switches. In mode-locked operation, pulses are generated that can be considered short compared with the period of modulation T = L/C (where L is the length of the perimeter of the cavity). Analysis shows that if the shift of the switching signals corresponds to the time of travel of a light pulse between Q-switches, the pulse in one direction will pass the Q-switches at instants of zero losses, while losses in the other direction will be maximized for a distance between Q-switches of L/4, and will be zero for a distance L/2. Experimental verification of the proposed method gave unidirectional lasing with an intensity ratio in the two directions of at least ...
Johnson & Johnson has had a formal energy program since the early 1970`s. A corporate energy department was formed as a result of the disruption of energy supplies and rising energy costs. Johnson & Johnson is a decentralized company with many independent operating companies throughout the world. The corporate energy department cuts across the different levels of management to delivery energy related information to the actual implementers at all of our locations worldwide. Like many other energy programs, Johnson & Johnson`s program had highs and lows depending on worldwide energy activities. Unlike many other corporate programs that were disbanded in the late 1980`s, our program remained in place, although there was not a high level of interest or attention. In the early 1990`s, the link was made between electricity generation and greenhouse gas emissions, initially by the Green Lights program and strongly reinforced by the United ...
There are two non-equivalent sites of yttrium in the lattice of Y{sub 2}SiO{sub 5}. Both of them may be occupied substitutionally by Er{sup 3+}, resulting in a laser active material. We measured absorption spectra of Y{sub 2}SiO{sub 5}:Er{sup 3+} at several low temperatures and we studied its emission spectrum at 4.2 K following selective excitation of individual Stark components of the {sup 4}I{sub 13}2/ to {sup 4}I{sub 15}2/ transition by the light of a tunable colour centre laser. The results of these two experiments allow classification of the absorption and emission lines into two independent systems, thus yielding two energy level schemes 1 and 2. Moreover, simple crystal field calculations strongly suggest from which Y{sub 2}SiO{sub 5} crystallographic site spectrum 1 arises, and from which one spectrum 2. (author)
There are two non-equivalent sites of yttrium in the lattice of Y_2SiO_5. Both of them may be occupied substitutionally by Er"3"+, resulting in a laser active material. We measured absorption spectra of Y_2SiO_5:Er"3"+ at several low temperatures and we studied its emission spectrum at 4.2 K following selective excitation of individual Stark components of the "4I_1_32/ to "4I_1_52/ transition by the light of a tunable colour centre laser. The results of these two experiments allow classification of the absorption and emission lines into two independent systems, thus yielding two energy level schemes 1 and 2. Moreover, simple crystal field calculations strongly suggest from which Y_2SiO_5 crystallographic site spectrum 1 arises, and from which one spectrum 2. (author)
This paper describes Fuji computed radiography (FCR) of Fuji Film for NDT (non-destructive testing). Imaging plate (IP) is a two-dimensional detector of X-ray, and shows higher photographic sensitivity than X-ray film. The output emission of IP provides a good linear relationship to X-ray intensity in a wide intensity range. When this emission can be digitized, the X-ray intensity can be also digitized. IP is applied to NDT as an inspection using X-ray. FCR provides higher photographic sensitivity than the conventional X-ray film method, which results in one-fifth to one-twentieth of irradiation time. Images with stable density can be obtained independent of the intensity. Since IP has a wide dynamic range, the variation of X-ray intensity of 1:500 can be expressed in a single image by single shot. High density record including 1000 images can be done using a 5.25 inch optical disk through the digital image processing and the electrical ...
Fe-doped TiO2 hollow spheres (Fe-THs) were synthesized by sol?gel process using carbon spheres as templates. The prepared samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), UV?vis diffuse reflectance spectrum (DRS), N2 adsorption?desorption isotherms, Electron paramagnetic resonance (EPR) spectroscopy and Photoluminescence emission spectroscopy (PL). UV?vis spectra showed that Fe3+ doping could extend the absorption edge to the visible region. EPR spectra showed that Fe3+ was incorporated into the crystal lattice of TiO2, which could inhibit the recombination of photo-induced electron?hole pairs and improve the photocatalytic activity. The photocatalytic activities of the prepared samples were evaluated for the degradation of dye Reactive Brillia...
Recent work has shown that natural hydrocarbon emissions can significantly affect the levels of urban and regional tropospheric ozone. We report on the reactivities of these biogenic trace gases, particularly isoprene, focusing on their importance in the production of aldehydes and peroxy radicals, leading to increased levels of hydrogen over regional forests. Hydrogen peroxide can lead to the wet oxidation of sulfur dioxide to acidic sulfate in aerosols, fogs, and clouds. In turn, acidic sulfate can act to as a light scattering aerosol and a source of cloud condensation nuclei (CCN), potentially leading to global cooling. Aerosol sulfate and other dissolved organic and inorganic compounds can also play important roles as a greenhouse species in the lower troposphere.
Photoemission-electron-microscopy (PEEM) is introduced as a tool for the characterization of organic electronic devices. PEEM-measurements are used for imaging as well as for spectroscopic analyses by illumination with light of a Hg-lamp (4.9 eV), a D2 lamp (7.3 eV), and with synchrotron radiation for resonant photoelectron spectroscopy. We determine the charge carrier concentration inside the channel region of the organic device and its lateral distribution. From resonant photoelectron spectroscopy (RPES) we deduce the electronic states which are accessible with the Hg and D2 illumination. Photoelectron-spectroscopy at selected areas ({mu}-PES) gives information on the absolute values of surface potentials in lateral resolution. We are able to perform these studies with applied voltages at the source- and drain-electrode.
LaPO4 single crystals lightly doped with Er3+, and codoped with Er3+ and Yb3+ have been grown by spontaneous nucleation in a lead phosphate flux. Absorption and luminescence spectra have been measured in the visible and near-IR regions and the excited state dynamics has been studied upon pulsed laser excitation. The obtained results have allowed the evaluation of the effective emission cross-sections around 1.5 ?m, that have been found to be similar to important oxide laser crystals doped with Er3+. Efficient visible upconversion has been observed upon excitation at 980 nm in the codoped crystals. This behaviour is attributed to Yb3+-Er3+ energy transfer processes.
The LCLS, a Free-Electron Laser (FEL) designed for operation at a first harmonic energy of 300 eV ({lambda} {congruent} 40{Angstrom}) in the Self-Amplified Spontaneous Emission (SASE) regime, will utilize electron bunches compressed down to durations of <0.5ps, or lengths of <150 {mu}. It is natural to inquire whether coherent radiation of this (and longer) wavelength will constitute a significant component of the total coherent output of the FEL. In this paper a determination of a simple upper bound on the IR that can be generated by the compressed bunches is outlines. Under the assumed operating parameters of the LCLS undulator, it is shown that that IR component of the coherent output should be strongly dominated by the x-ray component.
Ultra High Vacuum (UHV) test setup for electron gun testing has been developed. The development of next generation light sources and accelerators require development of klystron as a radio frequency power source, and in turn electron gun. This UHV electron gun test setup can be used to test the electron guns ranging from high average current, quasi-continuous wave to high peak current, single pulse etc. An electron gun has been designed, fabricated, assembled and tested for insulation up to 80 kV under the programme to develop high power klystron for future accelerators. Further testing includes the electron emission parameters characterization of the cathode, as it determines the development of a reliable and efficient electron gun with high electron emission current and high life time as well. This needs a clean ultra high vacuum to study these parameters particularly at high emission current. The ...
Classical semiconductor physics has been continuously improving electronic components such as diodes, light-emitting diodes, solar cells and transistors based on highly purified inorganic crystals over the past decades. Organic semiconductors, notably polymeric, are a comparatively young field of research, the first light-emitting diode based on conjugated polymers having been demonstrated in 1990. Polymeric semiconductors are of tremendous interest for high-volume, low-cost manufacturing (''printed electronics''). Due to their rather simple device structure mostly comprising only one or two functional layers, polymeric diodes are much more difficult to optimize compared to small-molecular organic devices. Usually, functions such as charge injection and transport are handled by the same material which thus needs to be highly optimized. The present work contributes to expanding the knowledge on the physical ...
In front of the risks linked with the increase of the greenhouse gas emissions in the atmosphere, the decision makers must take into consideration first, the scientific advice of climatic change experts, and second, the considerable inertia of the climatic system. Thus, any action implemented so far will have an impact all along the 21. century and later whatever the future human activities. The aim of this memento is to sensibilize the decision makers about the possible consequences of their choice in terms of volume of greenhouse gases and of medium- and long-term evolution: 1 - stakes, role of local decision-makers (greenhouse effect and climatic change, France's international commitment, stakes, liabilities of local decision makers, decentralization laws, local plans of fight against greenhouse effect, public information and dialogue); 2 - urbanism and transports (urban displacements, alternatives to individual cars, collective transportation systems, ...
Light Weight Composite Mirrors for Science Instruments. Composite Optics, Inc. San Diego, CA. INNOVATION. Light weight, large aperture reflectors of graphite ...
Bremstrahlung Isochromat Spectroscopy (BIS). The XES spectra were collected using a Specs electron gun for the excitation and the XES 350 grating monochromator and channel plate system from Scienta as the photon detection. Spectra were collected in 'normal mode,' where the electron gun kinetic energy (KE) and the energy position of the center of the channel plate were both fixed and the energy distribution in the photon (hv) spectrum was derived from the intensities distributed across the channel plate detector in the energy dispersal direction. The polycrystalline Ce sample was oxidized by exposure to air at ambient pressures. After introduction to the ultra-high vacuum system, the oxidized sample was bombarded with Ar, to clean the topmost surface region and stabilize the surface and near surface regions. Although CeO{sub 2} would be the thermodynamically preferred composition in an oxygen rich environment, the combination of a vacuum environment and ion etching may ...
... significant change of spontaneous radiation intensity. It is very sensitive technique allowing the observation of small changes of light absorption. ...
Sources of industrial emissions of 1,3-butadiene are discussed both by process (production, consumers) and type (equipment leaks, point sources). Quantification of the emissions are presented, as reported...Full Text Available
In the 80's, because of the oil crisis, the Natural Gas (NG) appeared as a fuel with a great potential for Diesel replacement in Heavy Duty Vehicles. At that time, PETROBRAS with other companies have developed partial conversion technologies from Diesel to NG, known as 'Dual Fuel'. Engine dynamometer and vehicle bus tests have been developed to verify its technical and economical viability. Because of several factors, the Dual Fuel Program did not advance and the experience was interrupted. At the same time, other experiences using NG Otto Cycle bus engines, manufactured in Brazil, have been conducted, mainly at Sao Paulo, nevertheless, without expansion. Currently, factors as increase of the NG converted light vehicles fleet; the NG excess in the National Market, which has contributed to the NG distribution net expansion; the Environmental Legislature in vigor, that continuously determine lower emission limits; the ...
Discussions were given on the characteristics of a diesel engine to emit unburned hydrocarbon (HC) created in a long idling operation. The engine tested in the experiment is a direct injection diesel engine with six water-cooled were investigated varying the jet hole diameter and length of the jet nozzle. In the initial operation period, the HC showed high values. This is thought because part of the injected fuel has deposited on the wall because of low combustion chamber wall temperature, and the fuel deposit that did not evaporate during combustion evaporated during expansion process and emitted unburned. The head was dismantled to investigate the carbon flowers deposited on the nozzle and the relationship between the carbon and the HC deposited on the head face and the combustion chamber wall. It was clarified that the HC increase was phenomenal compared with that of the carbon. This is because the injected fuel was adsorbed into the carbon, part of it remained into the expansion ...
A new exhaust cleaning system is introduced, aiming to remarkably reduce NOx emission using a type of EGR method (hybrid EGR) of feeding back the exhaust from an exhaust cleaning ternary catalyst provided gasoline engine to the Diesel engine intake on one hand and, on the other hand, aiming to reduce even the emitted particulates using an exhaust supplying gasoline engine driven supercharger for an enhanced Diesel engine supercharging. The hybrid EGR system used here can uniformly reduce the emitted NOx under any load conditions and, as compared with the conventional type, is two to three times more effective, with the EGR rate kept constant. The exhaust concentration is approximately 10%. An sample of the hybrid EGR was simulated, and it was shown, as compared with the original non-supercharged Diesel engine, that the emitted NOx decreased to 1/3 or 1/4, that the exhaust concentration was approximately the same, and that the total fuel consumption was less, as ...
The introduction of positron emission tomography (PET)/magnetic resonance (MR) systems into medical practice in the foreseeable future may not only lead to a gain in clinical diagnosis compared to PET/computed tomography (CT) imaging due to the superior soft-tissue contrast of the MR technology but can also substantially reduce exposure of patients to ionizing radiation. On the other hand, there are also risks and health effects associated with the use of diagnostic MR devices that have to be considered carefully. This review article summarizes biophysical and biological aspects, which are of relevance for the assessment of health effects related to the exposure of patients to both ionizing radiation in PET and magnetic and electromagnetic fields in MR. On this basis, some considerations concerning the justification and optimization of PET/MR examinations are presented - as far as this is possible at this very early stage. Current safety standards do not take into ...
Attention was focused on the fission process in light nuclear systems. A model calculation based on the transition-state model of nuclear fission was applied to [sup 47]V fission as populated through multiple entrance channels and to fusion-fission cross sections for production of [sup 28]Al through three different entrance channels. Angular distributions are shown for different mass channels of the [sup 29]Si+[sup 27]Al reaction at E[sub lab] = 125 MeV. Pronounced structure is seen in the symmetric and near-symmetric fission channels from the [sup 24]Mg+[sup 24]Mg reaction; cross sections for binary fragment emission are shown for E[sub lab] = 90 MeV. A large Bragg-curve detector was used in this experiment. Ways to optimize detector response were studied; in addition, the Bragg detector was instrumented with an internal position-sensitive multiwire proportional counter.
Attention was focused on the fission process in light nuclear systems. A model calculation based on the transition-state model of nuclear fission was applied to {sup 47}V fission as populated through multiple entrance channels and to fusion-fission cross sections for production of {sup 28}Al through three different entrance channels. Angular distributions are shown for different mass channels of the {sup 29}Si+{sup 27}Al reaction at E{sub lab} = 125 MeV. Pronounced structure is seen in the symmetric and near-symmetric fission channels from the {sup 24}Mg+{sup 24}Mg reaction; cross sections for binary fragment emission are shown for E{sub lab} = 90 MeV. A large Bragg-curve detector was used in this experiment. Ways to optimize detector response were studied; in addition, the Bragg detector was instrumented with an internal position-sensitive multiwire proportional counter.
This study presents a rapid and selective method for the recovery of lanthanides and yttrium, existing in economically interesting concentrations, from red mud, the byproduct of the alumina production. The leaching process is based on the extraction of these elements with diluted nitric acid from red mud under moderate conditions and without using any preliminary treatment. Several parameters such as leaching agents, contact time, temperature, pressure and solid to liquid ratio were investigated in order to achieve an optimum recovery. The process followed here was selected taking into account its efficiency for the selective recovery of yttrium and lanthanides, but also its suitability for the subsequent liquid-liquid extraction of the leaching solution for the separation of the individual lanthanides. The achieved recovery percentages were for Y about 90%, for the investigated heavy lanthanides (Dy, Er, Yb) up to 70%, for the middle ones (Nd, Sm, Eu, Gd) up to 50% and for the group ...
This study presents a rapid and selective method for the recovery of lanthanides and yttrium, existing in economically interesting concentrations, from red mud, the byproduct of the alumina production. The leaching process is based on the extraction of these elements with diluted nitric acid from red mud under moderate conditions and without using any preliminary treatment. Several parameters such as leaching agents, contact time, temperature, pressure and solid to liquid ratio were investigated in order to achieve an optimum recovery. The process followed here was selected taking into account its efficiency for the selective recovery of yttrium and lanthanides, but also its suitability for the subsequent liquid-liquid extraction of the leaching solution for the separation of the individual lanthanides. The achieved recovery percentages were for Y about 90%, for the investigated heavy lanthanides (Dy, Er, Yb) up to 70%, for the middle ones (Nd, Sm, Eu, Gd) up to 50% and for the group ...
The following industrial-scale power station processes are compared with natural gas/light fuel oil heating: Conventional steam generation, steam generation with gas turbine upstream, gas turbine process with low-pressure-waste heat boiler and cogeneration. Industrial gas turbines between 10 and 25 MW are compared with one another; typical boilers and industrial turbines are described. CO{sub 2} and NO{sub x} emissions are indicated. The steam turbines used are the efficient and robust turbines used in industry, wherever possible they are built as single-line plant with the gas turbine. (orig.) [Deutsch] Es werden folgende Industriekraftwerksprozesse mit Erdgas-Leichtoelfeuerung verglichen: Konventioneller Dampfprozess, Dampfprozess mit Vorschaltgasturbine, Gasturbinenprozess mit ND-Abhitzekessel und Kombianlage. Die Industriegasturbinen zwischen 10 und 25 MW werden gegenuebergestellt und typische Kessel und Industrieturbinen vorgestellt. ...
Observations of anisotropies in the brightness temperature of the 21 cm line of neutral hydrogen from the period before reionization would shed light on the dawn of the first stars and galaxies. In this paper, we use large-scale semi-numerical simulations to analyse the imprint on the 21 cm signal of spatial fluctuations in the Lyman-alpha flux arising from the clustering of the first galaxies. We show that an experiment like the Square Kilometer Array (SKA) can probe this signal at the onset of reionization giving us important information about the UV emission spectra of the first stars and characterizing their host galaxies. SKA-pathfinders with ~ 10% of the full collecting area should be capable of making a statistical detection of the 21 cm power spectrum at redshifts $z\\lesssim 20$. We then show that the SKA should be able to measure the three dimensional power spectrum as a function of the angle with the line of sight and discuss the use ...
We report results from a 50 ks XMM-Newton observation of the dust-reddened broad-line quasar FTM 0830+3759 (z=0.413) selected from the FIRST/2MASS Red Quasar survey. For this AGN, a very short 9 ks Chandra exposure had suggested a feature-rich X-ray spectrum and HST images revealed a very disturbed host galaxy morphology. Contrary to classical, optically-selected quasars, the X-ray properties of red (i.e. with J-Ks> 1.7 and R-Ks> 4) broad line quasars are still quite unexplored, although there is a growing consensus that, due to moderate obscuration, these objects can offer a unique view of spectral components typically swamped by the AGN light in normal, blue quasars. The XMM-Newton observation discussed here has definitely confirmed the complexity of the X-ray spectrum revealing the presence of a cold (or mildly-ionized) absorber with Nh ~10^{22} cm^-2 along the line of sight to the nucleus and a Compton reflection component accompanied by an intense Fe K ...
In car parks of considerable length, the removal of exhaust emissions, is carried out by air-conditioning systems mainly through transverse ventilation over short routes. The required air-conditioning ducts frequently produce a reduction in the available parking space simply due to their presence, resulting in restrictive effects on the level of acceptance by the users. In such cases, remedial action can be taken by creating ductless longitudinal ventilation. Depending on the required room air quality in the zones with the highest level of pollution, the volumetric flows for longitudinal disposal are no greater than those for conventional transverse ventilation. In conjunction with architecturally clear and positive lighting designs, clearly laid out car parks with a friendly atmosphere can be created which the user will be pleased to accept. (orig./BWI)
In response to the decisions adopted at the Third Session of the Conference of the Parties to the United Nations Framework Convention on Climate Change (Kyoto conference for the prevention of global warming) of 1997, hybrid vehicles, electric vehicles, and the like are being announced of their completion or placed on the market one after another as low pollution vehicles with CO2 emission to cause global warming reduced. Fuji Electric Co., Ltd., is engaged in the development of a DC-DC converter for hybrid vehicles in cooperation with Nissan Motor Co., Ltd. The product is characterized in (1) that it is small in size and light in weight because a step-down converter and an emergency step-up converter are integrated; (2) that it enjoys a high efficiency rate of 89%; (3) that its service life is long thanks to its design free of aluminum electrolytic capacitors; and (4) that it is provided with various reliability improving features, such as ...
Integration of positron emission tomography (PET) and magnetic resonance (MR) has become a topic of increasing interest to the imaging community over the past two years. In this text, the authors attempt to distinguish facts from fiction concerning such integrated systems. Analysis of existing information of combined imaging on existing brain PET/MR systems and imaging experience with PET-computed tomography (CT) is reviewed. Various types of system integration of PET and MR are discussed with completely independent systems on one hand and completely integrated systems with the possibility of simultaneous data acquisition on the other hand. Furthermore, it is discussed, what simultaneous data acquisition with nuclear imaging systems combined with MR or CT really means, as technical simultaneity may not be relevant in light of the pharmacokinetics of the nuclear tracers used. The authors conclude that combining PET/MR is an interesting research ...
The report presents a long-range plan for a broad-based, coordinated research, development and market transformation program for reducing the lighting energy intensities in commercial and residential buildings in California without compromising lighting quality. An effective program to advance lighting energy efficiency in California must be based on an understanding that lighting is a mature field and the lighting industry has developed many specialized products that meet a wide variety of light needs for different building types. Above all else, the lighting field is diverse and there are applications for a wide range of lighting products, systems, and strategies. Given the range of existing lighting solutions, an effective energy efficient lighting research portfolio must be ...
The Kyoto Protocol foresees emission trading but does not yet specify verification of (uncertain) emissions. This paper analyses a setting in which parties can meet their emission targets by reducing emissions, by investing in monitoring (reducing uncertainty of emissions) or by (bilaterally) trading permits. We derive the optimality conditions and carry out various numerical simulations. Our applications suggest that including uncertainty could increase compliance costs for the USA, Japan and the European Union. Central Europe and the Former Soviet Union might be able to gain from trading due to higher permit prices. Emissions trading could also lower aggregate uncertainty on emissions.
Eu-#alpha#-SiAlON (Eu_m_/_2Si_1_2_-_m_-_nAl_m_+_nO_nN_1_6_-_n) was synthesized with nominal compositions having small m and n values, by firing the powder mixture of Eu_2Si_5N_8, #alpha#-Si_3N_4, AlN, and Al_2O_3 at 1900 "oC for 6 h under 1 MPa nitrogen atmosphere. The ratio of the oxidation state of Eu"2"+/Eu"3"+ was estimated from the X-ray absorption fine structure (XAFS) measurement. The observed X-ray absorption near edge spectrum (XANES) showed that the Eu ion in Eu-#alpha#-SiAlON was mainly in divalent state but also coexisted with a small amount of Eu in the trivalent state. The crystal structure of Eu-#alpha#-SiAlON was refined by the Rietveld analysis of the X-ray powder diffraction patterns. The lattice constants of the samples increased with increasing m and n values. The excitation band of Eu-#alpha#-SiAlON ranged from the ultraviolet to the visible light region and a broad emission band centered at about 590 nm were observed. The ...
Aerosol and gas measurements were made with the University of Minnesota Mobile Laboratory (UMML) during the VISTTA programme near Page, Arizona. The UMML was stationed on Zilnez Mesa approx. 65 km east of the Navajo coal-fired power plant. Measurements were made both in and out of the power plant plume and were made during the day and night. Measured parameters included aerosol size distributions, Aitken nuclei count, ozone and sulphur dioxide concentrations, the aerosol light scattering coefficient, and meteorological parameters including ultraviolet radiation intensity. Concentrations of NO and NO/SUB/x were occasionally measured. Data show clear evidence of gas-to-particle conversion in the plume with aerosol volume being added in the 0.01 MUm - 0.32 MUm dia. range and new particles being formed. The observed excess aerosol volume depends strongly upon the SO/SUB/2 concentrations and the time of day with none observed in plume parcels which were not exposed to ...
An electron moving over the surface of a diffraction grating will transfer a part of its kinetic energy to radiation via a velocity synchronous coupling with a slow space harmonic component of the field. Since the phase velocity of a slow space harmonic is less than the speed of light, the slow components decay exponentially, or evanesce, with distance above the grating and the evanescence scale is determined by the product of the relative velocity, #beta#, the relative energy, #gamma#, and the wavelength #lambda#. Thus, in the relativistic regime, good electron - grating coupling can be maintained at beam heights that are greater than the emitted wavelength. In order to explore this regime a series of experiments have been carried out with moderately energetic beams and an experiment with the 70-MeV beam at the Accelerator Test Facility is in the planning stage. The work has two basic goals: the first is to explore the characteristics of the spontaneous ...
The emission of #alpha# particles in coincidence with the most deeply inelastic heavy-ion reactions has been studied for "1"8"1Ta + "1"6"5Ho at 1354 MeV laboratory energy and /sup nat/Ag + "8"4Kr at 664 MeV. #alpha# particle energy spectra and angular distributions, in coincidence with a projectile-like fragment, were acquired both in the reaction plane and out of the reaction plane at a fixed in-plane angle. The in-plane data for both systems are employed to show that the bulk of the #alpha# particles in coincidence with the deep-inelastic exit channel can be explained by evaporation from the fully accelerated fragments. Average velocity diagrams, #alpha#-particle energy spectra as a function of angle in several rest frames, and #alpha#-particle angular distributions are presented. The out-of-plane #alpha# particle angular distributions and the #gamma#-ray multiplicities are used to study the transfer and partitioning of angular momentum between the two fragments. ...
The aim was to compare the energy consumption by private and commercial vehicles with that of public transport facilities constituting urban street traffic, and to evaluate the influence of various traffic related plans such as green waves (where cars are able to drive through the town with relatively few accelerations and braking) streets with lower speed limits and special lanes and priorities for buses. The traffic pattern in four Copenhagen streets (Jagtvej, Soelvgade, Bredgade and Strandvejen) were measured and analyzed both in, and not in, the rush hour, and a special model was used to calculate the energy consumption. The model defines degree of acceleration and slow-down and speed when calculating energy consumption with regard to various driving patterns. It also calculates carbon dioxide emission. It was found that energy consumption decreased with increasing driving speed at 10-60 km/h for all vehicles. The case of buses is a little different because of ...
The aim was to compare the energy consumption by private and commercial vehicles with that of public transport facilities constituting urban street traffic, and to evaluate the influence of various traffic related plans such as green waves (where cars are able to drive through the town with relatively few accelerations and braking) streets with lower speed limits and special lanes and priorities for buses. The traffic pattern in four Copenhagen streets (Jagtvej, Soelvgade, Bredgade and Strandvejen) were measured and analyzed both in, and not in, the rush hour, and a special model was used to calculate the energy consumption. The model defines degree of acceleration and slow-down and speed when calculating energy consumption with regard to various driving patterns. It also calculates carbon dioxide emission. It was found that energy consumption decreased with increasing driving speed at 10-60 km/h for all vehicles. The case of buses is a little different because of ...
A computerised glow curve deconvolution (CGCD) analysis was applied to the main dosimetric peak of #alpha#-Al_2O_3:C in order to study the effects of light on the glow curve shape. It was shown that both the light-induced signal and the light-induced fading effects tend to shift the main dosimetric peak to higher temperatures and at the same time change its shape. Furthermore it was confirmed that the magnitude of the light-induced signal depends on radiation history and, by increasing the duration of light exposure, the magnitude of the light-induced signal reaches a plateau, thereby implying the saturation of the phototransfer process. (author).
Since the end of the 1990s, good quality lighting was that which balanced the needs of humans, economic and environmental issues, and architectural design. Recent studies aimed to find a correlation between environmental lighting and human performance and health, with positive results. What is known, is that insufficient or inappropriate light exposure can disrupt standard human rhythms which may result in adverse consequences for performance, safety, health. By studying the relationship between human physiology and light, research in photobiology has advanced to the point where some attempts to foresee what the lighting practice will be in future. The question is if lighting practice and lighting practitioners are ready for changes. This paper has the aim of introducing the recent discove...
The transverse light clock, in uniform translatory motion, is usually adopted to prove the necessity of the relativistic time dilation, according to the invariance of the velocity of the light, while the former postulate of the Special Relativity is respected by the symmetrical behavior of the clock. In this paper it is instead demonstrated that the behavior of the moving longitudinal light clock must involve unusual Lorentz distortions of the space, travelled by the light, to respect both the postulates of the Special Relativity.
The 8 papers in the report deal with the following areas: Introduction to diesel particulate emissions, alternative fuels, and the transit industry; Technical problems and policy issues associated with the 1991 bus emissions standards; Reducing transit bus emissions: comparative costs and benefits of methanol, particulate traps, and fuel modification; Effects of applying emissions averaging, trading, and banking to transit buses; Strategic review of heavy-duty engine emission regulations and alternate fuels; Meeting bus emissions standards--a perspective; Economic evaluation of bus maintenance contracting; Objectives for a transit-bus-fleet management data, information, and knowledge exchange.
Starting with a #LAMBDA#-nucleus potential, a semi-empirical formula, which gives a fairly satisfactory account of the ground state #LAMBDA#-binding energy of light hypernuclei, if the very light nuclei are ignored has been obtained. (author).
In this study, a miniature fiber-optic radiation detector has been developed using a water-equivalent organic scintillator for electron beam therapy dosimetry. Usually, two kinds of light signals such as fluorescent and Cherenkov lights are generated in a fiber-optic radiation detector when a high-energy electron beam is irradiated. The fluorescent light signal is produced in the scintillator and is transmitted through a plastic optical fiber to a remote light-measuring device such as a PMT or a photodiode. The Cherenkov light could be also produced in the plastic optical fiber itself and be detected by a light-measuring device. Therefore, it could cause problems or limit the accuracy of the detection of a fluorescent light signal that is proportional to dose. The objectives of this study are to measure, characterize and eliminate Cherenkov ...
This study was an evaluation of the performance of self-applied, blue light, light-emitting diode therapy in the treatment of mild-to-moderate inflammatory acne on the face, concerning: 1) time to improvement...Full Text Available
... to light-light a laser or directed energy weapon would ... space-based components... .the most likely threats are direct ascent anti-satellite weapons; ...
The resulting emissions of the firing of ceramic products of all type are described, the factors are enumerated to diminish the emissions in the kilns and the technologies applied in the kilns to reduce these emissions while carrying out energy saving are described briefly. (author)
This paper summarizes the current scientific and technological knowledge about greenhouse gas emissions from various agricultural practices and the manufacturing of food. The study also provides estimates that compare agriculture-related alternatives for reducing greenhouse gas emissions.
In this study, a regional dynamical model (WRF) is used to drive biogenic emission models to calculate high resolution (10 x 10 km) biogenic emissions of isoprene (C_5H_8), monoterpenes (C_1H_1_6), and nitric oxide (NO) in China. This high resolution biogenic inventory will be available for the community to study the effect of biogenic emissions on photochemical oxidants in China. The biogenic emissions are compared to anthropogenic emissions to gain insight on the potential impact of the biogenic emissions on tropospheric chemistry, especially ozone production in this region. The results show that the biogenic emissions in China exhibit strongly diurnal, seasonal, and spatial variations. The isoprenoid (including both isoprene and monoterpenes) emissions are closely correlated to tree density and strongly vary with ...
Full text: Thermoluminescence (TL) is a phenomenon of lightemission caused by heating a pre-irradiated material. When ionizing radiation hits a TL material, electrons are freed from some atoms and moved in the material, leaving behind 'holes' of positive charge. Subsequently when the TL material is heated, the electrons and the 'holes' re-combine, and release the extra energy in the form of light. The light intensity can be measured, and related to the amount of energy initially absorbed through exposure to the ionizing radiation. In nineteen sixties thermoluminescence dosimeters (TLD) became popular for dosimetric applications in view of their small size, sensitivity and accuracy. Consequently, in early seventies, several countries started adopting of TLD for personnel monitoring. The idea of introducing TLD to replace the then prevalent film dosimeter for personnel monitoring in India was mooted and ...
A specific application of single photon emission tomography to the relative quantitation of the pituitary region is described together with the results obtained in 19 patients with pituitary adenoma...Full Text Available
activities, including the combustion of diesel fuel in heavy-duty vehicles and jet fuel in aircrafts. Current details on emissions from the transportation and other...
It is shown that the interpretation of the experimental results reported in the publication "Storage of Light in Atomic Vapor" by D.F.Phillips et al., Phys. Rev.Lett. 86, 783 (2001) [quant-ph/0012138] is incorrect. The experimental observation of this paper can be consistently explained in the framework of standard concepts of the physics of optical pumping and has nothing to do with "storage of light", or "dynamic reduction of the group velocity", or "light pulse compression".
The influence of additionally injected short-wavelength photobleaching light on the radiation hardness of Ge-doped graded index fibers working at 1,300 nm wavelength is investigated. Predictions are complicated by the fact that more efficient shortwave bleaching light experiences higher radiation-induced loss. Promising results are found for low fiber temperatures (approx-lt -50 C) and bleaching light of about 835 nm wavelength.
Assuming the gluon field is well approximated by instanton configurations we derive a light quarks determinant and calculate its contribution to the specific heavy quarks correlators -- namely, the heavy quark propagator and heavy quark-aniquark correlator, receiving the instanton generated light-heavy quarks interaction terms contributions. With these knowledge we calculate the light quark contribution to the interaction between heavy quarks, which might be essential for the properties of a few heavy quarks systems.
Institutional and organizational models ... Review individual centre institutional and organizational models in the light of the tasks to be performed by
Hamiltonian light-front dynamics of quantum fields may provide a useful approach to systematic nonperturbative approximations to quantum field theories. The authors investigate inequivalent Hilbert-space representations of the light-front field algebra in which the stability group of the light front is implemented by unitary transformations. The Hilbert space representation of states is generated by the operator algebra from the vacuum state. There is a large class of vacuum states besides the Fock vacuum which meets all the invariance requirements. The light-front Hamiltonian must annihilate the vacuum and have a positive spectrum. Relations are exhibited of the Hamiltonian to the nontrivial vacuum structure. 30 refs.
A self-seeded free electron laser (FEL) provides a high gain and extraction efficiency for the emitted light. An accelerator outputs a beam of electron pulses to a permanent magnet wiggler having an input end for receiving the electron pulses and an output end for outputting light and the electron pulses. An optical feedback loop collects low power light in a small signal gain regime at the output end of said wiggler and returns the low power light to the input end of the wiggler while outputting high power light in a high signal gain regime.
We revisit the case of a light neutralino LSP in the framework of the MSSM. We consider a model with eleven free parameters. We show that all scenarios where the annihilation of light neutralinos rely mainly on the exchange of a light pseudoscalar are excluded by direct detection searches and by Fermi measurements of the gamma-flux from dwarf spheroidal galaxies. On the other hand, we find scenarios with light sleptons that satisfy all collider and astroparticle physics constraints. In this case, the lower limit on the LSP mass is 12.6 GeV. We discuss how the parameter space of the model will be further probed by new physics searches at the LHC.
We consider light waves propagating clockwise and other light waves propagating counterclockwise around a closed path in a plane (theoretically with the help of stationary mirrors). The time difference between the two light propagating path orientations constitutes the Sagnac effect. The general relativistic expression for the Sagnac effect is discussed. It is shown that a gravitational wave incident to the light beams at an arbitrary angle will not induce a Sagnac effect so long as the wave length of the weak gravitational wave is long on the length scale of the closed light beam paths. The gravitational wave induced Sagnac effect is thereby null.
The mass deployment of electric and plug-in hybrid electric vehicles (EVs and PHEVs) that rely on low greenhouse gas (GHG) emission electricity generation has great potential to significantly reduce the consumption of petroleum and other high CO2-emitting transportation fuels. The vision of the Electric and Plug-in Hybrid (EV/PHEV) Vehicles Roadmap is to achieve by 2050 the widespread adoption and use of EVs and PHEVs, which together represent more than 50% of annual LDV (light duty vehicle) sales worldwide. In addition to establishing a vision, this roadmap sets strategic goals to achieve it, and identifies the steps that need to be taken to accomplish these goals. This roadmap also outlines the roles and collaboration opportunities for different stakeholders and shows how government policy can support the overall achievement of the vision. The strategic goals for attaining the widespread adoption and use of EVs and PHEVs worldwide by 2050 ...
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 ...
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 ...
Sulfur poisoning from engine fuel and lube is one of the most recognizable degradation mechanisms of a NOx adsorber catalyst system for diesel emission reduction. Even with the availability of 15 ppm sulfur diesel fuel, NOx adsorber will be deactivated without an effective sulfur management. Two general pathways are currently being explored for sulfur management: (1) the use of a disposable SOx trap that can be replaced or rejuvenated offline periodically, and (2) the use of diesel fuel injection in the exhaust and high temperature de-sulfation approach to remove the sulfur poisons to recover the NOx trapping efficiency. The major concern of the de-sulfation process is the many prolonged high temperature rich cycles that catalyst will encounter during its useful life. It is shown that NOx adsorber catalyst suffers some loss of its trapping capacity upon high temperature lean-rich exposure. With the use of a disposable SOx trap to remove large portion of the sulfur ...
Consensus reached in the last few years that fourth generation light source will most likely be a X-ray or a UV coherent source based on single-pass high-gain free electron laser (FEL), such as Self Amplified Spontaneous Emission (SASE), or seeded high-gain harmonic-generation (HGHG) free electron lasers. High-gain (>10"7) required for single-pass FEL puts great constrain on the quality of electron beam, and demands detailed distribution information of electron beam in six-dimension. The typical accelerator system for single-pass FEL consists of a photocathode RF gun injection system, a linac and magnetic bunch compressors, and a long undulator. The major challenges in beam diagnostics for single-pass FEL are to characterize the pico-seconds high-brightness electron beam in six-dimension produced by photocathode RF gun injector, and improve the stability and reliability of the photocathode RF gun injection system. Characterization of short ...
A prototype for a quasi-cw, and high-average power free electron laser (FEL) driven by a 15 MeV superconducting rf linac has been developed, and constructed at Tokai, JAERI since 1989. Cryogenic and accelerating fields' performances of four JAERI superconducting accelerator modules have been realized without any serious problem in the FEL accelerator vault and experimental hall. Since modification and related maintenance of the cryogenic refrigerator system for the driver were completed in the middle of October 1995, the system has run with no trouble, and the driver has been continuously run very successfully up to now. The optical resonator system and related electron beam transport system have been modified to realize larger acceptance than the old for both of the undulator radiation and energetic electron beam in 1995 Japanese fiscal year. In the modification, an alignment and distance measurement system has been newly developed, and successfully applied to actual preparatory ...
The adhesion of a Mg:Ag cathode to the tris-(8-hydroxyquinoline) aluminum (Alq{sub 3}) in organic light emitting devices (OLEDs) can be greatly enhanced by a remote plasma treatment of the Alq{sub 3} layer using either air or N{sub 2} prior to metal deposition. The altered surface properties which lead to increased sticking coefficients of Mg and Ag, as well as enhanced adhesion, are attributed to the introduction of new functional groups into the organic layer, as observed by X-ray photoelectron spectroscopy (XPS). The storage life of the plasma treated devices in air without any capping treatment, as judged by a visible deterioration of the cathode, was increased by approximately five to six times compared to untreated OLEDs. Current-voltage characteristics and EL efficiency, however, were shown to deteriorate for devices incorporating either an air or an N{sub 2} plasma treated Alq{sub 3} layer. For OLEDs subjected to short treatment times with an N{sub 2} ...
A thermophotovoltaic (TPV) generator for electric vehicles has been designed and developed. In this paper we focus on the combustion system and the heat regenerator. The system has been designed to work as a range extender for electric vehicles. This solution would provide energy always available on the vehicle, which would run even if the battery level were low. Several configurations for the burner and for the heat exchanger have been investigated and a comparison of these is presented. The different solutions have been studied both theoretically and experimentally. In this paper, we report on the work carried out to build a TPV device capable of yielding 6 kW of electric power to recharge the battery pack of an electric city-car. The project has been divided into four steps: (1) pre-design of different configurations of the burner and heat exchanger using non-commercial software 'TPV Design Tool 1.0'; (2) testing of the pre-designed generators with a CFD code ...
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 ...
Interest in renewable and clean energies such as hydrogen has increased because of the high level of polluting emissions, increasing costs associated with petroleum and the escalating problems of global climate change. In the presence of a light source, a microbial photosynthetic process provides a system for the conversion of some organic compounds into biomass and hydrogen. Using Rhodopseudomonas palustris as a cell-factory, hydrogen photo-evolution was investigated in a photobioreactor (PBR) irradiated either from one or two opposite sides. Irradiating the photobioreactor from only one side, in the presence of malic acid, a reactor hydrogen production of 2.786 l(H{sub 2}) PBR{sup -1} was achieved. When the PBR was irradiated from two opposite sides, hydrogen photo-evolution increased to 3.162 l(H{sub 2}) PBR{sup -1}. Experiments were carried out using inoculum from either the retardation or the exponential growth phases. Using the latter, ...
Ethanol has excellent fuel properties, such as high octane, high heat of vaporization and low photochemical reactivity in the atmosphere. It is less volatile than gasoline and there is lower smog formation from evaporative emissions of pure ethanol compared to gasoline. As such, ethanol has emerged as an important alternative energy source that is sustainable, efficient, cost effective, convenient and safe. In 2006, global production of ethanol reached 13.5 billion gallons, up from 12.1 billion gallons in 2005. However, in light of the current debate of food versus fuel, the industry must shift to non-food feedstocks. This paper described an emerging technology to cost-effectively produce ethanol from sweet sorghum stalks, the most promising alternative feedstock to corn, via solid state fermentation (SSF). Experiments of advanced solid state fermentation (ASSF) for ethanol production from sweet sorghum by Saccharomyces cerevisiae were ...
In light of the recent rapid increase in the fossil fuel prices it is meaningful to evaluate the impact of these price changes in the economics of dual-purpose desalination projects producing electricity and fresh water simultaneously. The price of crude oil and LNG (Liquefied Natural Gas) has increased by about 200% and 100% during the past three or four years. The uranium price has also increased by nearly 500% during the same period. The purpose of this paper is to analyze and compare the economics of SMART (System-integrated Modular Advanced ReacTor) which is being developed as a small size PWR type and the LNG Combine Cycle coupled with MED (Multi-Effect Distillation) which are being acknowledged as promising energy sources for the future in Korea. The methods of analysis used in this paper are the lifetime leveled cost method for the power and water cost calculation and the power credit method for the total cost allocation. DEEP (Devaluation Economic ...
In light of the recent rapid increase in the fossil fuel prices it is meaningful to evaluate the impact of these price changes in the economics of dual-purpose desalination projects producing electricity and fresh water simultaneously. The price of crude oil and LNG (Liquefied Natural Gas) has increased by about 200% and 100% during the past three or four years. The uranium price has also increased by nearly 500% during the same period. The purpose of this paper is to analyze and compare the economics of SMART (System-integrated Modular Advanced ReacTor) which is being developed as a small size PWR type and the LNG Combine Cycle coupled with MED (Multi-Effect Distillation) which are being acknowledged as promising energy sources for the future in Korea. The methods of analysis used in this paper are the lifetime leveled cost method for the power and water cost calculation and the power credit method for the total cost allocation. DEEP (Devaluation Economic ...
A 450 MeV Synchrotron Radiation Source, Indus-1 is being constructed at Centre for Advanced Technology at Indore in central India. This paper narrates our experience in construction and alignment of synchrotron machines which was first of its kind for most of us. Careful design, planning and execution of the work yielded modest results so that alignment accuracies between 0.1 to 0.3 mm could be achieved (in booster synchrotron) and, which have proved to be adequate up till now. The building of the SRS complex was constructed such that machine rings have their foundations isolated from rest of the building. A number of 100 x 150 mm size steel plates were embedded in the concrete of floor and walls to serve as base for reference surveying marks which were established later. The pre-injector and booster ring are enclosed in a radiation shielding zone with separate ventilation system. Dipoles, quadrupoles and a few sextupoles were fiducialised during their field mappings; on a CNC ...
An overview of emissive display technologies is presented. Display types briefly described include: cathode ray tubes (CRTs), field emission displays (FEDs), electroluminescent displays (ELDs), and plasma display panels (PDPs). The critical role of phosphors in further development of the latter three flat panel emissive display technologies is outlined. The need for stable, efficient red, green, and blue phosphors for RGB fall color displays is emphasized.
In this report is described the sources to nitrogen emission and how the emission have changed over time. The cost and effect of the proposals given by the Swedish Environmental Protection Agency to cope with the emission of nitrogen to the sea is also treated. A separate chapter describes what we know today about phosphorus and eutrophication Basic document to report SNV--4735. 25 figs, 11 tabs
Proper estimation of shipping emissions is essential for an impact assessment of shipping on air quality and health in port cities and coastal regions. In the Netherlands shipping is an important source of particulate matter. This report provides an internationally accessible and transparent summary and description of the methodologies used in the Netherlands Pollutant Release and Transfer Register (PRTR) to estimate PM emissions from shipping, including recently implemented updates.
This article analyses the role of energy intensity and the relationship between CO{sub 2} emissions and primary energy in order to explain the evolution of CO{sub 2} emissions by unit of real GDP. It also distinguishes two different meanings of CO{sub 2} emissions Kuznets curve hypothesis: the weak and the strong sense. It considers the case of Spain in the period 1972-1997 as an example in which there is not any evidence supporting this hypothesis in either sense. (author)
This paper reviews emission standards, technologies to control emissions, and the cost of these controls. It is concluded that international bodies will increasingly set minimum emissions, these standards will continue to be reduced, and in addition new substances will be controlled. The cost of this control will likely not exceed 0.5 cents per kWe-hr. 4 refs., 3 tabs.
The CO{sub 2} emissions can be reduced by using economic instruments, like carbon tax. This project included two specific questions related to CO{sub 2} taxation. First one was the economic effects of increasing CO{sub 2} tax and decreasing other taxes. Second was the economic adjustment costs of reducing net emissions instead of gross emissions. A computable general equilibrium (CGE) model was used in this analysis. The study was taken place in Helsinki School of Economics
Pollutant emissions due to fossil fuel and biomass energy utilization in Turkey have been estimated. Standard emission factors were used for estimating the levels of particulate matter, sulfur oxides, nitrogen oxides, carbon monoxide, volatile organic compounds, and aldehydes. The results are presented for different fuels and energy-consuming sectors for the reference year 1987. Total Turkish emissions vs energy consumption are presented for every fifth year since. 1960. (author).
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 ...
This thesis consists of an introduction and five included papers. Of these, four papers are published in international journals and the fifth was submitted for review in April 2000. Emphasis has been placed on both naturally and artificially generated light hydrocarbons in petroleum fluids and their proposed source rocks as well as direct application of light hydrocarbons to oil/source rock correlations. Collectively, these papers describe a strategy for interpreting the source of the light hydrocarbons in original oils and condensates as well as the source of the asphaltene fractions from the reservoir fluids. The influence of maturity on light hydrocarbon composition has also been evaluated. The papers include (1) compositional data on the light hydrocarbons from thermal extracts and kerogen pyrolysates of sediment samples, (2) light hydrocarbon data of oils ...
The costs of greenhouse gas emission-reductions vary among countries depending on emission levels, technologies used, past emission-reduction achievements, path of economic development, fuel mix, and initial endowment of hydrocarbon resources. The criterion of cost-effectiveness therefore suggests that the ways should be found to encourage emission reductions in the countries where the required costs of reduction of additional unit of emissions are the lowest. These countries usually face crucial capital constraints and have other development priorities than investing in reduction of greenhouse gas emissions. Developed countries could invest their resources in the former Soviet Union and the east European countries to achieve the same level of reduction of greenhouse gases with lower costs than they could in their own countries.
Proposed features of the competitive electricity market in Ontario were reviewed. The speaker predicted that demand for renewable energy in Ontario`s competitive electricity market will be affected by green power, emissions trading, labelling, and renewables portfolio standard. Under current regulations retailers can charge customers a premium for purchasing electricity generated by `green` sources. The existing limits on emissions of sulphur dioxide, nitrogen oxides and carbon dioxides will remain in place, but an emissions cap and trading program for all Ontario-based generation is an option to consider. Ontario`s Market Design Committee (MDC) has recommended the implementation of emissions trading for electricity-related air pollutants for all generators located in Ontario. The complex mechanics of emission trading are explained. The MDC recommendation of the use of standard ...
This report focuses on air quality at the Nevada Test Site (NTS) for 1994. A general description of the effluent sources are presented. Each potential source of NTS emissions was characterized by one of the following: (1) by monitoring methods and procedures previously developed at NTS; (2) by a yearly radionuclide inventory of the source, assuming that volatile radionuclides are released to the environment; (3) by the measurement of tritiated water concentration in liquid effluents discharged to containment ponds and assuming all the effluent evaporates over the course of the year to become an air emission; or (4) by using a combination of environmental measurements and CAP88-PC to calculate emissions. Appendices A through J describe the methods used to determine the emissions from the sources. These National Emission Standards for Hazardous Air Pollutants (NESHAP) ...
This study investigates the carbon dioxide (CO2) emissions patterns in coordination with the economic development of Taiwan. The resulting quadratic relationship between emissions and income are partly due to the structural change of energy supply in Taiwan, with the introduction of nuclear energy in 1980 to 1986. This relationship is quite unique and different from the N-shaped relationships in some developed countries (de Bruyn and Opschoor, 1997; Friedl and Getzner, 2003). The CO2 emissions in Taiwan increase with the increasing imports of raw materials for economic activities and the increasing use of electricity. There is no evidence that the substantial increase of Taiwan's service sector contributed to slowing its CO2 emissions.
Method for determining the concentration of atomic species in gases and solids. Measurement of at least two emission intensities from a species in a plasma containing the species after a sufficient time period has elapsed after the generation of the plasma and during a second time period, permits an instantaneous temperature to be established within the sample. The concentration of the atomic species to be determined is then derived from the known emission intensity of a predetermined concentration of that species in the sample at the measured temperature, a quantity which is measured prior to the determination of the unknown concentration, and the actual measured emission from the unknown species, or by this latter emission and the emission intensity of a species having known concentration within the sample.
A pin hole camera assembly for use in viewing an object having a relatively large light intensity range, for example a crucible containing molten metal in an atomic vapor laser isotope separation (AVLIS) system is disclosed herein. The assembly includes means for optically compressing the light intensity range appearing at its input sufficient to make it receivable and decipherable by a standard video camera. To accomplish this, the assembly utilizes the combination of interference filter and a liquid crystal notch filter. The latter which preferably includes a cholesteric liquid crystal arrangement is configured to pass light at all wavelengths, except a relatively narrow wavelength band which defines the filter's notch, and includes means for causing the notch to vary to at least a limited extent with the intensity of light at its light incidence surface.
Heterobarrier blocking structure InGaAlP visible light laser diodes employing a thin active layer (0.04 {mu}m) and asymmetry coatings have been fabricated. The high light-output power operation with this heterobarrier blocking structure was investigated. The light-output power versus cw current curve was linear up to 43 mW and a maximum light output power of 51 mW was obtained. A high-power operation such as 20 mW was maintained at 40 {degree}C. Stable oscillation in the fundamental transverse mode was obtained up to 30 mW. These results show that this heterobarrier blocking structure supplies a sufficient current confinement effect even under a high-light output power operation.
The objectives of this study were to characterize the changes of VOC material emission profiles over time and develop a method to account for such changes in order to enhance a source identification technique that is based on the measurements of mixed air samples and the emission signatures of individual building materials determined by PTRMS. Source models, including powerlaw model, doubleexponential decay model and mechanistic diffusion model, were employed to track the change of individual material emission signatures by PTRMS over a ninemonth period. Samples of nine typical building materials were tested individually for nine months and later in combination to obtain actual mixture emissions. VOC emissions from each material were measured in a 50liter smallscale chamber. Chamber air was sampled by PTRMS over a 28day period to determine their emission rate ...
To predict air quality properly at a given location, it is necessary to identify all emission sources that will have significant impact at that location. Furthermore, the atmospheric pollutants that are emitted by these sources must be identified and quantitatively characterized. Once the air-quality predictions have been made, it is desirable to have some historical air-quality data for comparison. An efficient means of obtaining this information is through the use of detailed emission inventories and an inventory of air-quality-monitoring stations. Therefore, as part of the Alberta Government/Industry Acid Deposition Research Program (ADRP), three comprehensive inventories have been developed, namely: a sulfur dioxide (SO/sub 2/) emission inventory, a nitrogen oxides (NOx) emission inventory, and an inventory of air-quality-monitoring stations. Volume 2, Design of the Emission ...
In the present thesis, the shell structure in exotic nuclei has been investigated. The focus of the work was on finding new experimental data in neutron-rich Cr and proton-rich Ca isotopes. The investigation of light Ca isotopes concentrated on the nucleus {sup 36}Ca which was produced in a knockout reaction from a radioactive {sup 37}Ca beam. For {sup 36}Ca, the excitation energy of the first 2{sup +} state has been measured for the first time. Furthermore, momentum distributions were analyzed using a Monte-Carlo simulation of the knockout reaction. This analysis yielded the contributions of neutrons from individual orbitals to the total knockout cross section. In principle, these may be used to calculate spectroscopic factors, but such a calculation is hampered by difficulties of present knockout-reaction models in predicting precise single-particle cross sections. The measured branching ratio to the ground and excited states, on the other hand, is close to the ...
The potential retinal hazard of dental visible-light photopolymerization units and the efficacy of protective lenses for reducing the potential hazards were assessed. The spectral radiance profiles of 11 visible-light photopolymerization units were measured; and the results were then weighted according to the American Conference of Governmental Industrial Hygienists (ACGIH) Blue Light and Thermal Hazard Functions. The results indicate that there are no thermal hazards to the retina even for the worst case condition. None of the blue-light hazard maximum permissible exposure times is short enough to be of concern unless the individual operator chooses to focus on the light source for an extended period. Those individuals who elect to stare at the light during curing procedures should consider the purchase of protective lenses. The special transmission profiles of ...
1. Eight deuteranopes matched a mixture of a monochromatic light on the long wave side of the neutral point and a violet (450 nm) primary to a fixed white as well as a monochromatic light on the short...Full Text Available
PurposeEctopic expression of light-sensitive proteins, such as channelrhodopsin-2, represent a novel approach for restoring light-detection capabilities to degenerated retina. A...Full Text Available
The activity of a basic peroxidase extracted at high pH from spinach (Spinacia oleracea) leaves is modified by an irradiation with 2-minute red light or 2-minute far red light. This...Full Text Available
Preliminary results from a large-scale testbed of advanced lighting control technologies at the Phillip Burton Federal Building at 450 Golden Gate Ave. in San Francisco are presented. The first year objective of this project is to determine the sustainable energy savings and cost-effectiveness of different lighting control technologies compared to a portion of the building where only minimal controls are installed. The paper presents the analyzed results from six months of tests focused on accurately characterizing the energy savings potential of one type of daylight-linked lighting controls compared to the lighting in similar open-planned areas without dimming controls. After analyzing a half year;s data, we determined that the annual energy savings for this type of daylight- linked controls was 41% and 30% for the outer rows of lights on the South and North sides of the building, ...
A rapid loss of far red light (FR) reversibility of red-light (R) stimulated elongation of maize coleoptile sections was observed. Reversal was not possible when the interval between R and FR treatment...Full Text Available
The diffuse background light in the Coma cluster is measured using isodensity tracings of B, G, V, and R photographic plates taken with the Palomar 1.2-m Schmidt telescope. The isodensity contours are calibrated using the star profile derived by Kormendy (1973). Between 4 and 14 arc min from the center, the surface brightness of the diffuse light decreases from approximately 26 to approximately 28 G magnitudes arc sec"-"2. The total magnitude in this annulus is G = 11.22, which is approximately 45 percent of the light in galaxies alone, or approximately 30 percent of the total. This does little to alleviate the ''missing mass'' problem. The isodensity contours and the equivalent profile of the diffuse light closely parallel the distribution of light in galaxies, implying no strong mass segregation. However, the background light appears to be bluer than the ...
This plan details the methods and procedures necessary to ensure a safe transition in the operation of the Light Duty Utility Arm (LDUA) System. The steps identified here outline the work scope and identify responsibilities to complete startup, and turnover of the LDUA to Characterization Project Operations (CPO).
A comparitive analysis is made of the principal characteristics of narrow-band and conventional semiconductor light amplifiers. It is shown that quasi-distributed filtering of the spontaneous radiation ensures a high gain and a low level of the spontaneous noise at the amplifier output.
Increased sensitivity to light-induced melatonin suppression characterizes some, but not all, patients with bipolar illness or seasonal affective disorder. The aim of this study was to test...Full Text Available
In green plants, the large bioelectric changes that photosynthetically active light stimulates make it difficult to observe electrical potential changes related to phytochrome photoconversion. As a...Full Text Available
Experimental techniques are presented that can be used to assay and correct for differential light scattering effects in circular dichroism spectra of biological macrostructures. The assay is based...Full Text Available
A brief discussion is given of the application of control monitoring and automation techniques to coal mining in the United Kingdom, especially of the use of microprocessors, for the purpose of enhancing safety and productivity. Lighting systems for the coal mine is similarly discussed.
The suprachiasmatic nucleus (SCN) of the hypothalamus is thought to play a critical role in circadian rhythm generation and entrainment to the light/dark cycle. In adult rats, the SCN shows a circadian...Full Text Available
DNA damage is a threat to genomic integrity in all living organisms. Plants and green algae are particularly susceptible to DNA damage especially that caused by UV light, due to their light dependency...Full Text Available
Homologous to bacteriorhodopsin and even more to proteorhodopsin, xanthorhodopsin is a light-driven proton pump that, in addition to retinal, contains a noncovalently bound carotenoid with a function...Full Text Available
Under anaerobic conditions, several species of green algae perform a light-dependent hydrogen production catalyzed by a special group of [FeFe] hydrogenases termed HydA. Although highly interesting...Full Text Available
The protein kinase CK2 (formerly casein kinase II) is thought to be involved in light-regulated gene expression in plants because...Full Text Available
During complementary chromatic adaptation (CCA), cyanobacterial light harvesting structures called phycobilisomes are restructured in response to ambient light quality shifts. Transcription of genes...Full Text Available
This publication describes the modification of the road traffic exhaust emission calculation model LIISA and presents the new calculation results. The model has already established its position as the most important inventory tool for regional road traffic emissions in Finland. The LIISA model calculates road traffic emissions as a whole. The system comprises of three separate models: 1. a model for calculating automobile emissions for the years 2001-2021, 2. a model for calculating emissions backwards for the years 1980-2000, 3. a model for calculating the emissions of motorcycles and mopeds. All three parts have been modified. The LIISA model is one of the submodels of the comprehensive LIPASTO calculation system developed at VTT Building and Transport. The LIPASTO model is an inventory tool for emissions regarding all traffic modes in ...
The primary objective of the work was to establish and verify cost and performance parameters for integrated concepts in which agricultural and other biomass derived pyrolysis oils are utilised as fuel for small scale heat and power production. Production of non-food value-added products was also considered. The cost and performance studies were carried out in Spain, Denmark, and Finland, using olive oil farming residues, straw, and rapeseed oil pressing residues and straw as fuels for pyrolysis, respectively. Use of forest residue wood fuel was also considered in the Finnish vase. A rather wide selection of biomasses was therefore studied within the project. The secondary objective was to generate experimental data to verify and support the critical features within these concepts. Experimental work, modelling, and techno-economic assessments were carried out within the project. The experimental part included: Determination of flash pyrolysis balances in a PDU-unit for four feedstock, ...
A systematic study of non-perturbative quantum structure of the massive light-front Schwinger model and QED(3+1) in the continuum formulation is outlined. The light-front Hamiltonian and field algebra are derived in the Weyl gauge using the Dirac-Bergmann constrained quantization. Unitary transformation to the light-cone gauge representation is performed and the gauge-invariant fermi field is constructed. The importance of the Schwinger term in the current-current commutation relations for the derivation of the fermionic vacuum structure and bosonization in two dimensions is indicated.
Attention is paid to the production mechanisms of light scalars that reveal their nature. We reveal the chiral shielding of the \\sigma(600) meson. We show that the kaon loop mechanism of the \\phi radiative decays, ratified by experiment, points to the four-quark nature of light scalars. We show also that the light scalars are produced in the two photon collisions via four-quark transitions in contrast to the classic P wave tensor q\\bar q mesons that are produced via two-quark transitions $\\gamma\\gamma\\to q\\bar q$. The history of spontaneous breaking of symmetry in quantum physics is discussed in Appendix.
The main pollutants from marine diesel engines are oxides of nitrogen (NOx), sulfur oxides (SOx) and particulates (soot). However, the proposed marine diesel engine emission regulations will primarily focus on the levels of NOx and SOx. In the future, once the proposed regulations are met, the limits and levels of other emissions will come under increasing scrutiny, such as particulates, hydrocarbons and carbon monoxide. Regardless of the type of pollutant, there are generally two classes of emission control: (1) techniques that reduce the amount of pollutant formed in the combustion process, or (2) prevent the pollutants from reaching the atmosphere. Unfortunately, some of these control techniques will not be able to meet the incoming regulations. Therefore, this paper identifies the diesel engine emissions of concern, the impending regulations, and the merits of current and future ...
Air toxics from the industrial wastewater treatment plants (IWTPs) impose serious health concerns on its surrounding residential neighborhoods. To address such health concerns, one of the key challenges is to quantify the air emissions from the IWTPs. The objective here is to characterize the air emissions from the IWTPs and quantify its associated uncertainty. An IWTP receiving the wastewaters from an airplane maintenance facility is used for illustration with focus on the quantification of air emissions for benzyl alcohol, phenol, methylene chloride, 2-butanone, and acetone. Two general fate models, i.e., WATER9 and TOXCHEM+V3.0 were used to model the IWTP and quantify the air emissions. Monte Carlo and Bootstrap simulation were used for uncertainty analysis. On average, air emissions fr...
We have shown Xanthium strumarium exhibit two distinct leaf movement rhythms with one occurring in continuous light and presumably related to an endogenous rhythm initiated by the “light-on”...Full Text Available
I report on a lattice computation of the energy of a system of two light quarks and two static antiquarks as a function of the separation of the static antiquarks. In terms of hadrons such a system corresponds to a pair of B mesons and its energy to the hadronic potential. I present selected results for different isospin, spin and parity combinations of the individual B mesons mainly focusing on those channels relevant to determine, whether two B mesons may form a bound tetraquark state.
Two millimeter long secondary root tips of etiolated mung bean (Phaseolus aureus) plants were given 4 minute consecutive treatments of darkness, red light, far red light, and acetylcholine...Full Text Available
We report an observation of a delayed all-optical routing/switching phenomenon based on ultraslow group velocity of light via nondegenerate four-wave mixing processes in a defected solid medium. Unlike previous demonstrations of enhanced four-wave mixing processes using the slow light effects, the present observation demonstrates a direct retrieval of the resonant Raman-pulse excited spin coherence into photon coherence through coherence conversion processes.
Using spectral hole-burning-based ultraslow group velocity in a dilute solid medium, we report enhanced photon echo efficiency three orders of magnitude higher than that in a nonslow light regime. The enhancement is due to exponentially increased absorption of an optical data pulse owing to the enhanced photon-atom interaction in an ultraslow light regime, whereas echo reabsorption is negligibly small due to group-velocity dependent population depletion.
The nuclear interaction probability of light charged particles in BaF[sub 2] crystals has been studied as a function of the incident particle energy. Light charged particles were identified in charge and mass by measuring their magnetic rigidity and their time-of-flight. The percentage of particles undergoing nuclear interactions has been measured for particles of charge from Z=1 to Z=6 and the experimental data are compared with the results of a model calculation. (orig.)
Light dependency of nitrate and nitrite assimilation to reduced-N in leaves remains a controversial issue in the literature. With the objective of resolving this controversy, the light requirement for...Full Text Available
Using the manifestly causal gluon propagator in the light-cone gauge, we evaluate two one-loop Feynman integrals which appear in the computation of the three-gluon vertex correction in the two-component formalism of the Yang-Mills gauge fields. We conclude that they both are finite for {omega} -> 2, where {omega} is the dimensional regulator. They belong to a class of finite one-loop light-cone integrals. (author). 7 refs.
For Stage II of the European Dioxin Project the following objectives were set: - Amendment of existing emission data collected for most relevant emission sources in order to reduce uncertainties of emission estimates. Collecting first emission data from countries not yet performing dioxin emission measurement programs. Extending the inventory of dioxin emissions to ambient air produced in Stage I by a complementary study on emissions to land and water. Extending the regional scope of data collection to countries in Central Europe. The report of Stage II of the European Dioxin Project is presented in 3 Volumes. Volume 1 contains an overview on the background and approach of different activities carried out and on the results obtained. These results are put into a broader view regarding the dioxin reduction measures in Europe leading to ...
The reaction mechanism underlying the 44 MeV/u {sup 40}Ar projectile break-up process has been studied on different targets, by measuring the coincidences between light particles or intermediate mass fragments detected in a large angular range, and projectile fragments or light charged particles. While the experimental data relative to projectile-like fragments (PLF) with charge close to the one of the projectile can be interpreted in the framework of a three source analysis, the anomalous light fragment production with Z {<=} 10 rather suggests `fission` as one of the possible decay mode of the highly excited projectile or PLF. It is also observed that a great amount of the forward detected light charged particles are correlated, and due to the break-up or decay of light excited ions. (author). 9 refs.
Research reported here reveals that the reduction of CO{sub 2} emissions into the atmosphere, is mainly dependent on the decrease of the use of fossil fuels, but also on the development of environment-friendly technology and greening of the environment. 2 refs.
An improved method of counting acoustic emission (AE) events from water-stressed stems of cedar (Thuja occidentalis L.) is presented. Amplified AEs are analyzed on a real time basis...Full Text Available
Measurements are reported of ultrasonic acoustic emissions (AEs) measured from sapwood samples of Thuja occidentalis L. and Tsuga canadensis (L.) Carr. during air dehydration....Full Text Available
An ASTER (advanced spaceborne thermal emission and reflection radiometer) is one of the image sensors. It is to be installed in an earth survey polar orbit platform satellite, EOS-AM1, which is to be launched in 1998, and it is going to start its operation. Data observed by the thermal infrared remote sensing of ASTER include the spectral emissivity, and the spectral emission reflectivity which is expressed by the function of temperature. It is required to overcome technical problems how to extract the spectral emissivity from the observed data. The spectral emissivity extracted from the remote sensing data by the MMD method, measured for samples collected in Cuprite area, Nevada, and/or measured at sampled points were compared to each other and discussed. The hemisphere spectral reflectivity, which is indirect spectral emissivity, agreed well with the direct ...
In order to investigate the effects ethanol-diesel blends and altitude on the performance and emissions of diesel engine, the comparative experiments were carried out on the bench of turbo-charged diesel...Full Text Available
A historical prospective mortality study was conducted on a cohort of 34 156 male members of a heavy construction equipment operators union with potential exposure to diesel exhaust emissions. This...Full Text Available
The Natural Gas Vehicle Challenge `92, organized by Argonne National Laboratory and sponsored by the US Department of Energy, the Energy, Mines, and Resources - Canada, the Society of Automotive Engineers, and many others, resulted in 20 varied approaches to the conversion of a gasoline-fueled, spark-ignited, internal combustion engine to dedicated natural gas use. Starting with a GMC Sierra 2500 pickup truck, donated by General Motors, teams of college and university student engineers strived to optimize Chevrolet V-8 engines operating on natural gas for improved emissions, fuel economy, performance, and advanced design features. This paper focuses on the results of the emission event, and compares engine mechanical configurations, engine management systems, catalyst configurations and locations, and approaches to fuel control and the relationship of these parameters to engine-out and tailpipe emissions of regulated ...
In VHTGR (Very High Temperature Gas-cooled Reactor), the radiation plays an important role in heat transfer through the cavity in RCCS (Reactor Cavity Cooling System). We performed the series of experiments to measure the emissivity using the infrared thermometer with wavelength range of 8#approx#14 #mu#m. As the first step, the transmittance of Zinc Selenide (ZnSe) window was measured to estimate the emissivity that can compensate the attenuation effect of window. The kind of gas with various concentrations in the cavity will be released during postulated accidents to the coolant type, so it is essential to estimate the effects of gas on the measurement of emissivity. In this manner we measured the emissivity with the air, the helium and the steam inside chamber. The results represent that the concentration of the air and the helium do not affect the emissivity significantly while ...
Spontaneous radiation by an atom in a Rydberg state is inhibited by use of parallel conducting planes to eliminate the vacuum modes at the transition frequency. Spontaneous radiation emission is observed to turn off abruptly at the cutoff frequency of the waveguidelike structure, and the natural lifetime is measured to increase by a factor of at least 20.
Simulations with a regional chemical transport model show that anthropogenic emissions of volatile organic compounds and nitrogen oxides (NOx = NO + NO2) lead to a dramatic diurnal...Full Text Available
Emissions of sulphur and nitrogen oxides are continuing to fall in Europe but rise in Asia, according to calculations based on individual countries' predictions of economic development. The upward trend is slower than in previous predictions. 2 refs., 2 figs., 2 tabs.
Proper assessment of the hypothesis which correlates polycyclic aromatic hydrocarbons (PAHs) with the unidentified infrared emission bands requires additional experimental laboratory data. In order to address this need, thermal infrared emission studies were performed on a subset of PAHs suggested to be of astrophysical importance. It was proposed that infrared emission from interstellar PAHs occurs following absorption of an ultraviolet photon. Since energy transfer to the ground electronic state can be rapid for a species in which intersystem crossing is negligible, the emission spectrum may be viewed as resulting from an equilibrium vibrational temperature (Leger and d'Hendecourt, 1987). This has been the basis for using infrared absorption spectra to calculate the corresponding emission spectra at various temperatures. These calculations were made using room temperature infrared ...
Air pollution abatement measures are not an end in themselves, and undesirable side effects should be taken into account. The proposed emission index takes into account the total emissions caused by a technical project as well as the effects of the individual pollutants.
The pharmacokinetic concepts of bioavailability and biotransformation are introduced into the assessment of public health risk from experimental data concerning the emissions of potentially mutagenic...Full Text Available
This study was undertaken to collect emissions performance data for Canadian and comparable American refineries. The objective was to examine parameters that affect refinery air emissions performance and develop methods or correlations to normalize emissions performance. Another objective was to correlate and compare the performance of Canadian refineries to comparable American refineries. For the purpose of this study, benchmarking involved the determination of levels of emission performance that are being achieved for generic groups of facilities. A total of 20 facilities were included in the benchmarking analysis, and 74 American refinery emission correlations were developed. The recommended benchmarks, and the application of those correlations for comparison between Canadian and American refinery performance, were discussed. The benchmarks were: sulfur oxides, nitrogen oxides, ...
Described herein are the results of the FY1994 research program for structural defects of silicon-based amorphous materials for solar cells. The study on light generation defects of the a-Si:H system and rejuvenation process by annealing establishes the effects of light irradiation time on changed neutral dangling bond density as a result of light irradiation at varying temperature of 77K, room temperature and 393K. The study on annealing to rejuvenate light generation defects of various types of a-Si-H systems establishes the activation energy distribution with respect to annealing to remove light-induced defects, showing that hydrogen affects the distribution of light-induced defects. The study on decaying process of light-induced ESR for undoped and N-doped a-Si:H systems observes the decaying process of light-induced ...
A survey of various mechanisms for particle emission in hydrodynamics is presented. First, in the case of sudden freeze out, the problem of negative contributions in the Cooper-Frye formula and ways out are presented. Then the separate chemical and thermal freeze out scenario is described and the necessity of its inclusion in a hydrodynamical code is discussed. Finally, we show how to formulate continuous particle emission in hydrodynamics and discuss extensively its consistency with data. We point out in various cases that the interpretation of data is quite influenced by the choice of the particle emission mechanism.
The production of and emission factors for the air-polluting matters sulfur dioxide, nitrogen oxides, carbon monoxide, hydrocarbons (esp. benz(a)pyrene), aldehyde and soot with regard to natural gas, excluding process furnaces, are dealt with. The comparison with other fuels indicates that only as to nitrogen oxides and carbon monoxide are emission factors equal in order of magnitude. As a summary measure of all air-polluting matters the emission index as proposed already in 1972 is applied. It shows emissions with single-room furnaces for heating oil EL to be six times as high as with natural gas; with black-coal briquettes the factor is at least 33, with wood chimneys about 200.
The Federal Republic of German (FRG) had uniquely strict emission legislation for particulates SO_2 and NO_X from fossil-fired power plants. The 13th Regulation to the Federal Emission Control Act required that by 1 July 1988 all large furnaces fired with solid or liquid fuels that would not be decommissioned by 1993 be retrofitted with SO_2 control technology. The emission limits are 15 per cent of the sulphur introduced with the fuel (400 mg/m"3 maximum) at thermal capacities above 300 MW. 1 ref., 9 figs, 15 bibliographies.
In this paper, the control scheme of a liquefied petroleum gas (LPG)-diesel dual-fuel engine with electronic control is illustrated, the external characteristics and load characteristics of the LPG-diesel dual-fuel engine and the diesel engine are compared and analysed, and the results of automobile road tests are also given. The experimental results show that, compared with diesel, the output performance of dual fuel is not reduced, while smoke emission of dual fuel is significantly reduced, NO{sub x} emission of dual fuel is hardly changed, but HC emission and CO emission of dual fuel are increased and fuel consumption of dual fuel is reduced. (Author)
The effect of atmospheric radioactive emissions from United Kingdom nuclear installations on acid deposition is assessed. Nitrogen oxide and ozone production resulting from and associated with discharges of airborne radioactivity, comparison with conventional emissions, and the direct effects of radioactive emissions on trees, are all discussed. (UK).
One requirement of a thermophotovoltaic (TPV) radiator is to efficiently emit photons at high temperatures to TPV cells for conversion to electric power. Because many candidate radiator materials with adequate structural properties display low emissivity, coatings or other surface modifications are required for enhancement of emissivity. Six plasma sprayed coatings and one textured surface demonstrated adequate thermal stability and emittance values of 0.8 or greater. Promising attributes of modified surfaces are identified.
This article, with 25 references, reviews the soil sources and sinks of carbon dioxide, methane, and nitrous oxide. The mitigation of greenhouse gas releases is discussed covering reduction of carbon dioxide emissions by a change in land use, the use of alternative waste disposal methods such as composting or recycling to reduce methane emissions, and management of nitrogen fertiliser applications to reduce nitrous oxide emissions. (Author)
Designing efficient policies for curbing greenhouse gas (GHG) emissions is of particular interest for todays policy makers, in view of global climate change threats. This paper analyses the options Switzerland has for curbing its CO{sub 2} emissions. Using MARKAL and MARKAL-NACRO models, it investigates, in particular effects of national and international carbon taxes. (author) 3 figs., 1 tab., 6 refs.
The report summarizes the results of a dioxin/furan emissions test of a secondary copper recovery cupola furnace equipped with an afterburner for hydrocarbon emissions control and two baghouses for particulate emissions control. The cupola furnace is used...
Greenhouse gas emissions from international maritime transport are exempt from liabilities under the Kyoto Protocol. Research into quantifying these emissions is ongoing, and influences policy proposals to reduce emissions. This paper presents a cargo-based analysis of fuel consumption and greenhouse gas emissions from New Zealand's international maritime transport of goods. Maritime transport moves 99.5% (by mass) of New Zealand's internationally traded products. It is estimated that 73% of visiting vessels' activity can be directly attributed to the movement of goods in and out of New Zealand. A cargo-based methodology was used to estimate that the international maritime transport of New Zealand's imports and exports consumed 2.5 million tonnes (Mt; 2.6 billion litres) of fuel during the year 2007, which generated 7.7 Mt of carbon dioxide (CO_2) emissions. Double-counting of ...
The method of life-cycle assessment (LCA) has been applied to cars with different power trains. As an example, the results for greenhouse gas (GHG) emissions are presented. They show possibilities and limits for the reduction of these emissions in the transportation sector by means of advanced technology. (author) 2 figs., 4 refs.
The method for calculating emissions to air has been revised, which has led to adjustments. Because of this, emissions in 1999 cannot yet be compared with previous years. Emissions in 1990 - 1998 are being recalculated now using the new method and are expected to be ready during 2001. Emissions to air of carbon dioxide (CO_2) in Sweden was 56.58 million tonnes in 1999, not including emissions from biofuels and international bunkers. The major sources of CO_2 emissions are the combustion of fossil fuels and the use of fuels for mobile sources. Total emissions to air of sulphur dioxide (SO_2) and nitrogen oxides (NO_x, counted as NO_2) in Sweden was 66 000 and 263 000 tonnes respectively in 1999. International bunkers are not included. The major source of SO_2 emissions is combustion of fossil fuels. Road traffic is the ...
The Baldwin Effect, a negative correlation between emission-line equivalent width and luminosity in active galactic nuclei, is still of interest as a diagnostic of accretion physics nearly thirty years after its discovery. This review examines recent developments in the study of correlations between line and continuum emission in AGNs, as measured both in ensembles and in individual sources.
This report presents estimates of the annual anthropogenic UK emissions of greenhouse gases for the years 1990-93 for submission under the Framework Convention on Climate Change. The gases considered are carbon dioxide, methane, nitrous oxide, nitrogen oxides, carbon monoxide and non-methane volatile organic compounds. Emissions of all the gases have declined since 1990. In particular, those of carbon dioxide have fallen by 4%; those of methane by 8% and those of nitrous oxide by 28%. Emission estimates are reported in the IPCC Standard Tables format disaggregated by source category and fuel. The methodology used for the estimates and how they relate to the UK National Atmospheric Emissions Inventory is discussed in an appendix. (author)
Fugitive dust emissions from stockpiles in the open storage yards of industrial zones and the subsequent atmospheric dust dispersion have brought about many ecological and economical problems. This paper introduces a new approach to reduce pollutant emissions by simply changing pile configuration and without affecting the operational activity on these parks. Flow around piles of different geometries and for various wind conditions was studied using previously validated Computational Fluid Dynamic (CFD) simulations. Different pile height scenarios were investigated corresponding to a constant material volume and a fixed angle of repose under various wind magnitudes. The results obtained were integrated in order to evaluate the rate of dust emissions for the various configurations considered. It was found that, for the range of wind conditions and pile dimensions tested, an optimal geometry exists which corresponds to the ...
The document presents an overview on atmospheric pollution in Lebanon, with an analysis of sources of pollution, their impact on local and global environment and their control.Local causes of pollution are mainly: -Thermal power plants of electric power production which produce 75% SO_2 emission and 60% dust - Industries, especially cement industry - Land transportation which produces 70% NOX emission and 50% CO_2 A description of air pollution caused by these three sectors is revealed. Pollutants derived from fuel combustion are analyzed. It is estimated that in 2010, Co_2 emission will reach 5204450 tons, SO_2 emission will be 136470 tons, NOX emissions 96870 and dust estimated to 4130 tons. CFC consumption and measures of control according to Montreal Protocol are described. Recommendations for control of air pollution in Lebanon within a national policy are presented.
The production of atmospheric pollutants in combustion processes depends on plant characteristic, combustion conditions and fuel quality. The influence of fuel quality on the emission of sulphur oxides, nitrogen oxides, carbon monoxide, dust and carbon dioxide and on the emission of some toxic pollutants, such as heavy metals and polycyclic aromatic hydrocarbons, is analysed. The comparison between the emission limits, fixed by the Italian legislation, and the uncontrolled pollutant emissions, produced by fossil fuel combustion in power plants and industrial use, shows that, in order to comply with the limits, a reduction of pollutant emissions is required through the use of abatement systems and cleaner fuels where natural gas has a primary role. The use of cleaner fuels is particularly required in heating plants and appliances for the residential sector, where the development of ...
This patent describes a low emission duel fuel engine system. It comprises: a dual fuel engine having a combustion chamber; a fuel oil supply connected to the engine; a fuel gas supply connected to the engine; and means connected between the fuel oil supply and the engine for injecting fuel oil into the engine. The means connected between the engine and fuel oil supply limiting the injection of fuel oil to the combustion chamber to pilot ignition quantities only, wherein the limiting means includes means for limiting the injection of fuel oil such that the exhaust emission of NO{sub x} is at an emission rate of less than 1 GM/PH-HR, whereby the exhaust emission performance of the dual fuel engine is enhanced.
The formaldehyde surface emission monitor (FSEM) has been developed for passive non-destructive measurement of formaldehyde (CH/sub 2/O) emission rates from CH/sub 2/O resin-containing materials. It is envisaged as a potential quality control and in-situ monitoring technique. For quality control applications to pressed-wood products, strong correlations between the results of the FSEM and environmentally controlled (small scale) chamber tests were observed. The FSEM is used to measure the cumulative CH/sub 2/O emission from a finite area of pressed-wood product during a fixed test period. The final result is reported as an average CH/sub 2/O emission rate (mg CH/sub 2/O/m/sup 2/h).
Investigations were conducted on the range of emission rates of NO, NO[sub 2], CO and hydrocarbons, and the thermal efficiencies produced by each burner on three production cookers, supplied by different Australian manufacturers. It was found that the emissions and efficiencies were markedly affected by (1) the thermal input, both with and without a load on the burner, and (2) the load-height to flame-length ratio, with a load on the burner. The effect of hydrocarbon leakage into the secondary/dilution air was investigated, to explain the observed correlation of hydrocarbon emission rate with dilution air flow. The hydrocarbons were found to arise from two sources: -leakage from the stabilisation ports at the base of the burner, which was found to be significant at the higher thermal input; -incomplete combustion of the fuel in the premix, which was the dominant source of hydrocarbons emissions at the ...
This report documents radionuclide air emission from the Hanford Site in 1997, and the resulting effective dose equivalent to the maximally exposed member of the public, referred to as the MEI. The report has been prepared in accordance with reporting requirements in the Code of Federal Regulations, Title 40, Protection of the Environment, Part 61, National Emissions Standards for Hazardous Air Pollutants, Subpart H, National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities. This report has also been prepared in accordance with the reporting requirements of the Washington Administrative Code Chapter 246-247, Radiation Protection-Air Emissions. The effective dose equivalent to the MEI from the Hanford Site`s 1997 point source emissions was 1.2 E-03 mrem (1.2 E-05 mSv), which is well below the 40 CFR 61 ...
Using a sample of 30,000 quasars from SDSS-DR7, we explore the range of properties exhibited by high-ionization, broad emission lines, such as CIV 1549. Specifically we investigate the anti-correlation between L_UV and emission line EQW (the Baldwin Effect) and the "blueshifting" of high-ionization emission lines. The blueshift of the CIV emission line is nearly ubiquitous, with a mean shift of 810 km/s for radio-quiet (RQ) quasars and 360 km/s for radio-loud (RL) quasars, and the Baldwin Effect is present in both RQ and RL samples. Composite spectra are constructed as a function of CIV emission line properties in attempt to reveal empirical relationships between different line species and the SED. Within a two-component disk+wind model of the broad emission line region (BELR), where the wind filters the continuum seen by the disk component, we find that RL ...
Activities of the Referenzlaboratorium Reinhaltung der Luft at Magdeburg as well as existing air pollution standards in the German Democratic Republic are reviewed. The laboratroy coordinates research and standardization in the field of industrial air pollution for the Ministry of Health. The standards provide orientation for emission control by state district health inspectorates. Emission limits (in g/m/sup 3/) which are international standards for 15 selected industries are listed. Emission limits (in g/m/sup 3/) of GDR standards, issued between 1971 and 1984 are also provided. They concern emission of brown coal dust from coal preparation plants, dust and chemical compound emission from metallurgical plants, dust emission from plants of the limestone and cement industry as well as from cupola furnace plants, boiler plants, plants of the wood industry and ...
Magnetically driven non-stationary acceleration of jets in active galactic nuclei results in the leading parts of the flow being accelerated to much higher Lorentz factors than in the case of steady-state acceleration with the same parameters. The higher Doppler-boosted parts of the flow may dominate the high-energy emission of blazar jets. We suggest that highly variable GeV and TeV emission in blazars is produced by the faster moving leading edges of highly magnetized non-stationary ejection blobs, while the radio data trace the slower-moving bulk flow. Thus, the radio and gamma-ray emission regions have different, but correlated, Doppler factors. High-energy emission is generated, typically within the optically thick core, in the outer parts of the broad-line emission region, avoiding the radiative drag on the faster parts of the flow. The radio emission ...
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 containing Canadian engines; importers of engines or machines for the purpose of ...
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 containing Canadian engines; importers of engines or machines for the purpose of ...
Measurements of ion-induced electron emission have been performed with helium and argon ions with energies between 300 and 900 eV on W, W with 10% Ti, Al, Al with 1% Cu, Al with 1% Si, Si, and Be. This article describes many of the important surface characteristics that influence the ion-induced electron emission. For low-energy ions, the substrate material was found to be less important as the velocity of the incident ion decreased. In the case of incident Ar"+ the substrate material had a negligible effect on the emission for this energy range. The presence of an adsorbed layer enhanced emission in all cases. Heating the substrates resulted in oxidation of the surfaces and a subsequent increase in emission. The electron emission from aluminum samples with smaller grain sizes was higher than samples of identical composition with larger grains. This effect is ...
The increasing diffusion of small-scale energy systems within the distributed generation (DG) paradigm is raising the need for studying the environmental impact due to the different DG solutions in order to assess their sustainability. Addressing the environmental impact calls for building specific models for studying both local and global emissions. In this framework, the adoption of natural gas-fueled DG cogeneration technologies may provide, as a consequence of cogeneration enhanced overall energy efficiency and of natural gas relatively low carbon content, a significant reduction of global impact in terms of CO2 emissions with respect to the separate production of electricity and heat. However, a comprehensive evaluation of the DG alternatives should take into account as well the impact due to the presence of plants spread over the territory that could increase the local pollution, in particular due to CO and NOx, and thus could worsen the ...
This study tried to reduce NO{sub x} and particulate emissions simultaneously in a high speed direct-injection diesel engine. Fuel-rich combustion was used to reduce NO{sub x} emission at initial combustion stage and high turbulence combustion was used to reduce particulate emission at diffusion combustion stage. Experiments were carried out to investigate the effects of high squish combustion chambers with small throat on combustion process and exhaust emissions. Results showed that in the high squish combustion chamber, both NO{sub x} and particulate emissions reduced with retarded injection timing. Endoscopic high speed photography was employed to analyze experimental results. In the original combustion chamber at the early combustion stage, the high luminosity flame tended to spread out of the cavity. Fuel-rich mixture burned slowly over the piston crown. In the high squish ...
Heavy-duty trucks and buses are substantial contributors to the atmospheric oxides of nitrogen (NO_x) inventory, but prediction of their emissions in real use remains inchoate. Continuous emissions of NO_x were recorded from Chassis dynamometer testing of eight vehicles using a variety of transient cycles, including the Central Business District schedule. NO_x data were treated to account for sampling time lag and presented against instantaneous vehicle axle power. Data were repeatable from run to run and test schedule, but vehicle type and test cycle both influenced the instantaneous emissions rates. However, the resulting correlations may be used for mobile source NO_x contribution estimation when combined with vehicle activity data. The emissions data were also presented as NO_x/CO_2, which are valuable for comparison with remote sensing emissions data. The overall average ratio ...
The ultra-precise photometric space satellite MOST (Microvariability and Oscillations of STars) will provide the first opportunity to measure the albedos and scattered light curves from known short-period extrasolar planets. Due to the changing phases of an extrasolar planet as it orbits its parent star, the combined light of the planet-star system will vary on the order of tens of micromagnitudes. The amplitude and shape of the resulting light curve is sensitive to the planet's radius and orbital inclination, as well as the composition and size distribution of the scattering particles in the planet's atmosphere. To predict the capabilities of MOST and other planned space missions, we have constructed a series of models of such light curves, improving upon earlier work by incorporating more realistic details such as: limb darkening of the star, intrinsic granulation noise in the star itself, tidal ...
Radiation damage and its recovery in the light emittance efficiency and the attenuation length of barium fluoride (BaF_2) scintillator have been investigated. The light yield and transmittance of small samples of BaF_2 scintillator were measured after #gamma#-irradiation from 0.5x10"4 to 1.1x10"5 Gy for deterioration, and after sunlight exposure for recovery. Suspension of deterioration was observed both in light yield and in attenuation length at an integrated dose of #gamma#-rays of about 10"4 Gy. Fairly good and quick recovery of the deteriorated BaF_2 scintillator was obtained by sunlight exposure. Using a Monte Carlo simulation method, the dependence of the light emittance efficiency on #gamma#-irradiation and sunlight exposure was studied. It has been found that the light emittance efficiency, as well as the attenuation length, is influenced by #gamma#-irradiation and sunlight ...
Although studied for many years the nature of the light scalar mesons remains controversial. Here we shall present a method, applicable for s-wave states located close to a threshold, that allows one to quantify the molecular part of a given state. When applied to the f{sub 0}(980) a dominance of the molecular component is found. In the second part, we show that requirements of field-theoretic consistency and chiral symmetry, when applied to the scattering of light pseudo-scalars, naturally lead to the appearance of dynamical poles in the scalar sector. A program is proposed on how to further investigate experimentally the mixing between these dynamical states and possible genuine quark states. (orig.)
1. Chronic exposure of male Microtus pennsylvanicus to photoperiods with 8, 10 and 12 hr of light per day results in gonadal regression, molt to winter pelage and significant reductions in body weight and food consumption relative to voles kept on photoperiods with 13 and 14 hr of light per day. 2. A precise critical daylength is observed in this species as exposure to photoperiods with 12 or fewer hours of light per day results in complete gonadal involution, seasonal molt and loss of body weight. 3. Pinealectomy abolishes all short-photoperiod induced responses in this species. PMID:2573458
A new analysis is developed for long secondary photocurrent transients which gives the distribution of trapped holes in valence band tail states. Thermally assisted tunneling to dangling bonds is implicated as the rate limiting step in hole-recombination. Light-soaking causes the energetically deeper hole traps with the longer residence times to be lost first and in the same number as would be expected for the increase in dangling bonds; This result supports a model which has hole trapping in valence tail states as a precursor to light induced dangling bonds.
It is shown that the direct Fourier synthesization of light beams allows one to create polarity-asymmetric waves, which are able, in the process of nonlinear interaction with a medium, to break its inversion symmetry. As a result, these "polar" waves may show the effect of optical rectification in nonlinear centrosymmetric media by generating light-induced dc electric polarization. At the same time, the waves of this type, due to their unusual symmetry properties, can be used for detecting the direction and sign of a dc electric field applied to the medium. The prospects of application of polar waves to data recording and processing are discussed.
The differences are highlighted of various aspects of behaviour of the luminescence signal from feldspar when stimulated by green light and when stimulated by infrared radiation. In respect of bleaching, a comparison is made of the influence of white light (daylight) on the two stimulated luminescence signals, as well as a comparison of the influence of infrared exposure on the green-stimulated signal with the influence of green exposure on the infrared-stimulated signal. The influence of preheating on the two stimulated signals is also compared. Light-emitting diode systems were used for both green and infrared stimulation. The observations are considered in relation to the mechanism relevant to green- and infrared-stimulated luminescence from feldspar. (author).
The differences are highlighted of various aspects of behaviour of the luminescence signal from feldspar when stimulated by green light and when stimulated by infrared radiation. In respect of bleaching, a comparison is made of the influence of white light (daylight) on the two stimulated luminescence signals, as well as a comparison of the influence of infrared exposure on the green-stimulated signal with the influence of green exposure on the infrared-stimulated signal. The influence of preheating on the two stimulated signals is also compared. Light-emitting diode systems were used for both green and infrared stimulation. The observations are considered in relation to the mechanism relevant to green- and infrared-stimulated luminescence from feldspar. (author).
PAMELA is a space telescope orbiting around the Earth since June 2006. The scientific objectives addressed by the mission are the measurement of the antiprotons and positrons spectra in cosmic rays, the hunt for anti-nuclei as well as the determination of light nuclei fluxes from Hydrogen to Oxygen in a wide energy range and with very high statistics. In this paper the charge discrimination capabilities of the PAMELA Time-Of-Flight system for light nuclei, determined during a beam test calibration, will be presented.
Given a Schwarzschild black-hole, the frame sigma at rest with respect to the Schwarzschild metric are chosen as reference-frames. In this locally non-inertial frames, a free falling body is shown to reach the speed of light on the horizon and then to travel faster-than-light inside the horizon. The usual Szekeres-Kruskal (SK) coordinates represent themselves frames that (with respect to the frames sigma) travel at subliminal speed outside, at luminal speed on, and at superluminal speed inside the horizon (so that SK frames always describe any free falling body as a standard, slower-than-light object). At last, black-holes are shown to be possible sources of tachyons.
Alpha particles, tritons, deuterons and protons accompanying /sup 252/Cf fission were registered in coincidence with both fission fragments by means of a system containing two-dimensional position-sensitive silicon detectors. Angular distributions, kinetic energy spectra of light charged particles as well as mass distributions of fission fragments in coincidence with light charged particles were measured. The experimental results are compared with some theoretical models.
Research at the world's accelerator- (storage-ring and linac) based light sources is one of the most dynamic and rapidly growing fields of science. It frequently results in direct benefits to society, thereby demonstrating the value of the research with very concrete examples, but this is not widely understood or appreciated outside of the immediate user community. Our growing group of light source communicators from facilities in Europe, Asia, and the Americas, inspired by the Interactions.org Web site created by high-energy (elementary-particle)physics communicators, concluded that a light source community Web site (lightsources.org) would be the best tool for establishing effective collaboration between the communications offices of the world's light sources and to maximize the impact of our efforts. We envision lightsources.org to serve as a one-stop-shopping site for information ...
In this study, wood samples were exposed to light irradiations (direct sunlight, xenon lamp, mercury vapour lamp) and thermal treatments were carried out in dry- and in humid conditions at 90degreeC. One part of the samples was covered by an aluminium plate during light irradiation. The samples under the aluminium plate also suffered considerable chemical changes, monitored by infrared technique and colour measurement. The sunlight produced greater colour change under the aluminium plate than the artificial light sources. During light irradiation, the carbonyl band having two maximum at 1700 and 1746cm-1 increased and the peak of the aromatic skeletal vibration arising from lignin (1510cm-1) decreased together with the guaiacyl vibrations at 1275cm-1. There was absorption decrease at 1174c...
... Division and the 82nd ABN Division spearheaded a ... attack through the stalled 90th Division to ... mi,_es, which included airborne infantrv, regular ...
The 12 months stability study of freshly produced refined soybean oil revealed that refined soybean oil stored in plastic containers in dark was more hydrolytically and oxidatively stable than that stored in other containers in light condition. There was no significant difference at P < 0.05 in free fatty acids and acid value of oil stored under light and dark conditions in tin and glass containers but there was significant difference at P < 0.05 in peroxide value of oil stored in light and dark conditions in all the storage containers. Light increased the degree of oxidative rancidity of refined soybean oil, the most in tin containers, followed by glass containers and the least in plastic containers. (author)
Energy savings from the use of daylighting in commercial buildings are realized through implementation of photoelectric lighting controls that dim electric lights when sufficient daylight is available to provide adequate workplane illumination. The dimming level of electric lighting is based on the signal of a photosensor. Current simulation approaches for such systems are based on the questionable assumption that the signal of the photosensor is proportional to the task illuminance. This paper presents a method that simulates the performance of photosensor controls considering the acceptance angle, angular sensitivity, placement of the photosensor within a space, and color correction filter. The method is based on the multiplication of two fisheye images: one generated from the angular sensitivity of the photosensor and the other from a 180- or 360-degree fisheye image of the space as ''seen'' by the photosensor. The paper ...
The inverse problem of interpreting the SS 433 optical light curves is solved for a geometrically thick model accretion disk around the compact relativistic object: most likely a black hole.
your eye to the SCN in your brain, so that light ... Owls are individuals who go to bed late, like to get up late in the moming. And the moming types, ...
A new technique to monitor light diffraction patterns electrically is applied to frog semitendinosus muscle fibers at various levels of stretch. The intensity of the diffraction lines, sarcomere length...Full Text Available
The nature of the `inner engine' that accelerate and collimate the relativistic flow at the cores of GRBs is the most interesting current puzzle concerning GRBs. Numerical simulations have shown that the internal shocks' light curve reflects the activity of this inner engine. Using a simple analytic toy model we clarify the relations between the observed $ \\gamma $-rays light curve and the inner engine's activity and the dependence of the light curves on the inner engine's parameters. This simple model also explains the observed similarity between the observed distributions of pulses widths and the intervals between pulses and the correlation between the width of a pulse and the length of the preceding interval. Our analysis suggests that the variability in the wind's Lorentz factors arises due to a modulation of the mass injected into a constant energy flow.
Shallow-water zooplanktivorous fish rely on their vision for foraging. In shallow water, feeding efficiency decreases in dim light and thus the fish cease foraging at crepuscular hours. Creatures living in the lower parts of their depth ranges are expected to be exposed to limited light levels for longer hours. However, observations of the zooplanktivore Dascyllus marginatus showed little change in foraging duration down to 40m deep. We asked whether the visual system's functionality changes with depth along the depth range of this damselfish; we examined eye and retina anatomy for changes in visual acuity and light sensitivity and used the optomotor response to test for spatial and temporal light summation. We found only minor changes in the anatomy of the eye that are not expected to aff...
In a laser system for converting infrared laser light waves to visible light comprising a source of infrared laser light waves and means of harmoic generation associated therewith for production of light waves at integral multiples of the frequency of the original wave, the improvement of said means of harmonic generation comprising a crystal having the chemical formula X.sub.2 Y(NO.sub.3).sub.5 .multidot.2 nZ.sub.2 o wherein X is selected from the group consisting of Li, Na, K, Rb, Cs, and Tl; Y is selected from the group consisting of Sc, Y, La, Ce, Nd, Pr, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Al, Ga, and In; Z is selected from the group consisting of H and D; and n ranges from 0 to 4.
We consider the Pauli theorem on the spin-statistics connection for faster-than-light particles. As the consequence of the unlocalizability of tachyons in space we conclude that their spin-statistics correlations are inverted.
New photometric observations of the variable star FG Sge, a rapidly evolving planetary nebula nucleus, were performed in 2003?2008. On 230 nights, we obtained 86 UBV and 155 BV RI (or R c , I c ) magnitude estimates. The maximum amplitude of the V-band light variations was >8 m . Six deep minima and four high maxima were observed. Analysis of the light curve has shown that the pulsation period of the star remained constant since 1991 and was P = 115 days. We have studied the wavelength dependence of the extinction at various phases of the light curve. The blueing of the B-V color at deep minima is interpreted as the result of light scattering in the circumstellar dust shell of the star formed by preceding dust ejections since 1992. Our spectroscopic observations performed on nine nights in...
The effects of time of seed maturation and dry seed storage and of light and temperature requirements during seed incubation on final germination percentage and germination rate were assessed for the invasive shrub Prosopis juliflora (Sw.) D.C., grown under desert environmental conditions of the United Arab Emirates (UAE). Seeds were collected from Fujira on the northern coast of the UAE at different times during the growing seasons (autumn, winter and spring) and were germinated immediately and after 8 months of dry storage under room temperature (20+-3degreeC). Seeds were germinated at three temperatures (15, 25 and 40degreeC) in both continuous light and darkness. The results showed significant effects for time of seed collection, seed storage, light and temperature of seed incubation a...
As the main forestry species in the Canary Islands (Spain), Pinus canariensis is frequently used in afforestation programs. Several nursery techniques are commonly employed to modify its morphology and physiology with the aim of improving post-planting survival and growth. In this work, we studied how fertilization and light regime treatments applied during the nursery period modify biomass allocation patterns and produce effects in gas exchange and root hydraulic conductance. Seedlings were grown for a 6-month period in the nursery under two light regimes (full sunlight and 40% PAR reduction), and three fertilization levels were applied in each light regime. Morphology, biomass allocation patterns, leaf gas exchange and hydraulic conductance of the whole root system were evaluated. Fertil...
The concept of the 'white-light cavity' has recently generated considerable research interest in the context of gravitational wave detection. Cavity designs are proposed using negative (or anomalous) dispersion in an intracavity medium to make the cavity resonate over a large range of frequencies and still maintain a high cavity build-up. This paper presents the first experimental attempt and demonstration of white-light effect in a meter long ring cavity using an intracavity atomic medium. The medium's negative dispersion is caused by bi-frequency Raman gain in an atomic vapor cell. Although the white light condition was not perfectly achieved and improvements in experimental control are still desirable, significantly broad cavity response over bandwidth greater than 20 MHz has been observed. These devices will have potential applications in new generation laser interferometer gravitational wave detectors.
... being designed for projected Minotaur IV launch load environments, with design objectives of light weight, integrated vibration isolation, low shock ...
A brief review of standard big bang nucleosynthesis theory and the related observations of the light element isotopes is presented. Implications of BBN on chemical evolution and constraints on particle properties will also be discussed.
The presence of an extraneous light gas must be taken into account in consideration of centrifugal separation of uranium isotopes, when there is inevitable leakage of such a gas through the gas sealant and/or leaking in from the atmosphere. Consideration is first given to the influence of the presence of the light gas on the maximum separative power. Then the basic equation for isotope separation containing a light gas is derived from Hirschfelder's diffusion equations. This equation is solved and the separative performance is expressed in terms of the shape factor and reflux parameter. The formulas for expressing the flow configurations of the gases are obtained for a simple model in which inflow and outflow prevail throughout the centrifuge. The corresponding equation for a model in which the gases flow in two concentric thin streams is also derived. It is concluded that the influence provided by the presence of a ...
green (both light and dark tones) and purple, bare areas are seen in ...... spatial scale continue to plague such efforts. Knowledge of the spatial ...
... gap" between the arrival ofquick response forces, such as the 82nd Airborne Division and the ... nd Airborne is just exactly that, light airborne infantry. ...
A method and apparatus for determining the condition of tissue or otherwise making chemical identifications includes exposing the sample to a light source, and using a synchronous luminescence system to produce a spectrum that can be analyzed for tissue condition.
In this model, without dark matter, the flat rotation curves of galaxies and the mass-to-light ratios of clusters of galaxies are described quantitatively. The hypothesis is that the agent of gravitational...Full Text Available
Hereditary hyperferritinemia cataract syndrome (HHCS) is a rare condition caused by mutations in the gene coding for the light chain of ferritin; it does not lead to iron overload, but it is associated...Full Text Available
A link is made in this paper between proposed low energy scenarios for different Western European countries and the amount of pollutants that may result from these scenarios. Air pollutant emissions are calculated for the ten countries for which low energy scenarios are available. These scenarios emphasize stringent energy efficiency, maximizing the use of renewable (other than nuclear) energy, and minimizing the use of fossil fuels. Under these low energy scenarios, the average per capita energy use (year 2030) in the ten countries is estimated as 97 GJ/person, which is a decrease of 38% relative to 1980. Using the energy consumption figures from the low energy scenarios, together with sector- and fuel-specific emission factors from Europe, the resulting emissions of SO_2 , NO_x , and CO_2 were computed. These estimates do not take into account any add-on pollution controls over and above what was in place in 1980, or ...
This paper deals with estimating aircraft landing and take-off (LTO) emissions (HC, CO, NO_x, SO_2) at 40 Turkish airports including the biggest airports, i.e. Ataturk International Airport (AIA) in Istanbul, Antalya Airport in Antalya and Esenboga Airport in Ankara in 2001. The calculation model is based on flight data recorded by the State Airports Authority. The flight data include the type and number of aircraft, number of passengers, amount of cargo etc., which depend on day-time and date. For the emission calculations the International Civil Aviation Organization (ICAO)-Engine emission data bank, which includes minimum and maximum values for both fuel flow rates and emissions factors, is used. By using first the minimum and then the maximum values from the data bank, two estimations of aircraft LTO emissions at Turkish airports are calculated: i.e. minimum and maximum ...
By August 2007, there were 438 nuclear power plants (NPPs) in operation worldwide, with a total capacity of 371.7 GW(e). Further, 31 units, totaling 24.1 GW(e), were under construction. During 2006 nuclear power produced 2659.7 billion kWh of electricity, which was 15.2% of the world's total. The vast majority of these plants use water-cooled reactors. Based on information provided by its Member States, the IAEA projects that nuclear power will grow significantly, producing between 2760 and 2810 billion kWh annually by 2010, between 3120 and 3840 billion kWh annually by 2020, and between 3325 and 5040 billion kWh annually by 2030. There are several reasons for these rising expectations for nuclear power: - Nuclear power's lengthening experience and good performance: The industry now has more than 12 000 reactor years of experience, and the global average nuclear plant availability during 2006 reached 83%; - Growing energy needs: All forecasts project increases in world energy demand, ...
By August 2007, there were 438 nuclear power plants (NPPs) in operation worldwide, with a total capacity of 371.7 GW(e). Further, 31 units, totaling 24.1 GW(e), were under construction. During 2006 nuclear power produced 2659.7 billion kWh of electricity, which was 15.2% of the world's total. The vast majority of these plants use water-cooled reactors. Based on information provided by its Member States, the IAEA projects that nuclear power will grow significantly, producing between 2760 and 2810 billion kWh annually by 2010, between 3120 and 3840 billion kWh annually by 2020, and between 3325 and 5040 billion kWh annually by 2030. There are several reasons for these rising expectations for nuclear power: - Nuclear power's lengthening experience and good performance: The industry now has more than 12 000 reactor years of experience, and the global average nuclear plant availability during 2006 reached 83%; - Growing energy needs: All forecasts project increases in world energy demand, ...
By August 2007, there were 438 nuclear power plants (NPPs) in operation worldwide, with a total capacity of 371.7 GW(e). Further, 31 units, totaling 24.1 GW(e), were under construction. During 2006 nuclear power produced 2659.7 billion kWh of electricity, which was 15.2% of the world's total. The vast majority of these plants use water-cooled reactors. Based on information provided by its Member States, the IAEA projects that nuclear power will grow significantly, producing between 2760 and 2810 billion kWh annually by 2010, between 3120 and 3840 billion kWh annually by 2020, and between 3325 and 5040 billion kWh annually by 2030. There are several reasons for these rising expectations for nuclear power: - Nuclear power's lengthening experience and good performance: The industry now has more than 12 000 reactor years of experience, and the global average nuclear plant availability during 2006 reached 83%; - Growing energy needs: All forecasts project increases in world energy demand, ...
This Statistical Report presents results from the physical Swedish Environmental and Economic Accounts for the years 1993 and 1995 according to the classification NACE. The Environmental Economic Accounts constitute an integrated and comprehensive system for environmental and economic statistics. Environmental data are systematically presented together with economic data in a common framework. The system can be used for analyses of various relationships between economy and environment. Data on emissions to air of carbon dioxide, sulphur dioxide, nitrogen oxides, carbon monoxide, methane, nitrous oxide and ammonia are presented for 39 industries, government services and private consumption. The use of energy commodities in monetary and physical terms are also presented for the same sectors. Economic, energy and emission data are also presented in environmental and economic profiles and indicators. Environmental and economic profiles provide an ...
To aid in the study of lower hybrid current drive as a means of current profile control, the radial profile and velocity distribution of the fast current-carrying electrons and their time evolution must be known. As part of the recent effort to understand this fast electron transport, a diagnostic has been installed on PBX-M to measure the electron cyclotron emission from the fast electrons. An oblique horizontal view of upshifted cyclotron emission in the midplane can give radial as well as velocity space information about the fast electrons. Emission in X mode frequencies refracted by the right-hand cutoff is radially localized. The observed emission at a specific frequency comes only from the radial region r_t_u_r_n=#0. Emission measured by this new diagnostic has been found to be radially localized as predicted. It is also expected that localized moments of the distribution ...
This presentation gives the results of a research programme aimed at evaluating exhaust emissions from ships moving within confined coastal zones, as in Piraeus harbour. The level of various exhaust emissions were estimated on the basis of a mathematical model applied for each sea traffic element (ship). Hourly and daily records of all ships` movements in different parts of the harbour were compiled, covering extended periods of time and associated with different shipping operational characteristics (peaks, lows, etc). In order to correlate the exhaust emissions from shipping with the quality of the air in the area of interest, land-based measurements for the same pollutants were carried out in selected locations, near the port and in the greater Athens area. This enabled the investigation of time and spatial diffusion of exhaust emissions from shipping within the area of interest, taking into account ...
The report gives results of a project conducted to create a file containing comprehensive data on all electric utilities in the US. The National Acid Precipitation Assessment Program's (NAPAP's) emissions inventory activities focus on the estimation of emissions from pollutants that contribute to acid deposition. Electric utilities, which emit a large share of total acid deposition precursor emissions, are important for modeling analyses. Data reported by states to the National Emissions Data System (NEDS) for the 1985 NAPAP Emissions Inventory and data reported to the U.S. Department of Energy (DOE) on EIA Form 759, EIA Form 767, FERC Form 423, and the Integrated Data Base System (IDBS) were matched and combined. The resulting 1985 National Utility Reference File (NURF) contains detailed unit level data for nearly 10,000 electricity generating plants.
This report is an assessment of emission-control costs for municipal-waste combustors (MWCs). The details of the cost estimates, including their development, components, and cost premises, are addressed. A model-plant approach was used in the sizing and costing of the emission control systems. Due to differences in the feed-waste characteristics, combustion parameters, and emissions, separate cost estimates were required for mass burning (MB), modular (MOD), refuse-derived fuel (RDF), and fluid-bed combustion (FBC) type furnaces. Cost estimates were developed for control of particulate matter (PM) emissions only and for control of both acid gas and PM emissions from the MWC model plants. Controlled PM emission levels of 0.03, 0.02, and 0.01 gr/dscf, corrected to 12% CO/sub 2/, and 90 and 70% reductions of HC1 and SO2, respectively, were used to develop the ...
We present the results of a study on the 1.4 GHz kpc-scale radio emission in the complete flux density limited MOJAVE sample, comprising 135 radio-loud AGNs. While extended emission is detected in the majority of the sources, about 7% of the sources exhibit only radio core emission. Many BL Lacs exhibit extended radio power and kpc-scale morphology typical of powerful FRII jets, while a substantial number of quasars possess radio powers intermediate between FRIs and FRIIs. This poses challenges to the simple radio-loud unified scheme, which links BL Lacs to FRIs and quasars to FRIIs. We find a significant correlation between extended radio emission and pc-scale jet speeds: the more radio powerful sources possess faster jets. This indicates that the 1.4 GHz (or low frequency) radio emission is indeed related to jet kinetic power. Various properties such as extended radio power and ...
The exhaust emissions of a Diesel direct injection Perkins engine fueled with waste olive oil methyl ester were studied at several steady-state operating conditions. Emissions were characterized with neat biodiesel from used olive oil and conventional Diesel fuel. Results revealed that the use of biodiesel resulted in lower emissions of CO (up to 58.9%), CO{sub 2} (up to 8.6%, excepting a case which presented a 7.4% increase), NO (up to 37.5%), and SO{sub 2} (up to 57.7%), with increase in emissions of NO{sub 2} (up to 81%, excepting a case which presented a slight reduction). Biodiesel also presented a slight increase in brake-specific fuel consumption (lower than 8.5%) that may be tolerated due to the exhaust emission benefits. Combustion efficiency remained constant using either biodiesel or Diesel fuel. The proposed alternative for Diesel fuel could significantly decrease the ...
The document gives statistics on the pollutive emissions from Danish power plants during the period 1987-1996, the main pollutants being sulphur dioxide, nitrogen oxides and carbon dioxide. Data on efficiency levels relative to the production of electricity and heating and on the power plants` contribution to the total emission of CO{sub 2}, NO{sub x}, and SO{sub 2} from energy consumption in Denmark, are presented, and also as corrected for the net import of electricity. Other data on the emission of each of these chemicals by power plants are presented as factual, and corrected in accordance with the net import of electricity, and as factual per consumed and produced energy unit at the power plants. Short notes on related Danish legislation are found in addition to information on sources, methods and definitions used as a basis for the production of this document. Emission from power stations is ...
Historically, the bulk production of electricity has been achieved by burning fossil fuels, with unavoidable gaseous emissions, including large quantities of carbon dioxide: an average-sized modern coal-burning power station is responsible for more than 10 Mt of CO{sub 2} each year. This paper details typical emissions from present-day power stations and discusses the options for their reduction. Acknowledging that the cuts achieved in the past decade in the UK CO{sub 2} emissions have been achieved largely by fuel switching, the remaining possibilities offered by this method are discussed. Switching to less-polluting fossil fuels will achieve some measure of reduction, but the basic problem of CO{sub 2} emissions continues. Of the alternatives to fossil fuels, only nuclear power represents a zero-carbon large-scale energy source. Unfortunately, public concerns over safety and radioactive waste have ...
This paper investigates the relationship between economic growth and pollutant emissions for a small and open developing country, Tunisia, during the period 1961-2004. The investigation is made on the basis of the environmental Kuznets curve hypothesis, using time series data and cointegration analysis. Carbon dioxide (CO{sub 2}) and sulfur dioxide (SO{sub 2}) are used as the environmental indicators, and GDP as the economic indicator. Our results show that there is a long-run cointegrating relationship between the per capita emissions of two pollutants and the per capita GDP. An inverted U relationship between SO{sub 2} emissions and GDP has been found, with income turning point approximately equals to $1200 (constant 2000 prices) or to $3700 (in PPP, constant 2000 prices). However, a monotonically increasing relationship with GDP is found more appropriate for CO{sub 2} emissions. Furthermore, the ...
This paper investigates the relationship between economic growth and pollutant emissions for a small and open developing country, Tunisia, during the period 1961-2004. The investigation is made on the basis of the environmental Kuznets curve hypothesis, using time series data and cointegration analysis. Carbon dioxide (CO2) and sulfur dioxide (SO2) are used as the environmental indicators, and GDP as the economic indicator. Our results show that there is a long-run cointegrating relationship between the per capita emissions of two pollutants and the per capita GDP. An inverted U relationship between SO2 emissions and GDP has been found, with income turning point approximately equals to $1200 (constant 2000 prices) or to $3700 (in PPP, constant 2000 prices). However, a monotonically increasing relationship with GDP is found more appropriate for CO2 emissions. Furthermore, the causality results show that ...
This paper investigates the relationship between economic growth and pollutant emissions for a small and open developing country, Tunisia, during the period 1961-2004. The investigation is made on the basis of the environmental Kuznets curve hypothesis, using time series data and cointegration analysis. Carbon dioxide (CO{sub 2}) and sulfur dioxide (SO{sub 2}) are used as the environmental indicators, and GDP as the economic indicator. Our results show that there is a long-run cointegrating relationship between the per capita emissions of two pollutants and the per capita GDP. An inverted U relationship between SO{sub 2} emissions and GDP has been found, with income turning point approximately equals to 1200 (constant 2000 prices) or to 3700 (in PPP, constant 2000 prices). However, a monotonically increasing relationship with GDP is found more appropriate for CO{sub 2} emissions. Furthermore, the ...
A method was developed in which the potential of various measures is assessed systematically with a view to meeting the future EU5 emission specifications. Varied boundary conditions are taken into account, and their influence on the PM-NOx tradeoff was investigated. The relative cost is compared to an existing EU4 injection system. It was attempted to apply these measures to the impending US regulations (Tier2 Bin5) and to offer an outlook to EU6. The result shows that it is possible in principle for a car of the 1600 kg class to reduce NOx emissions while maintaining the EU4-PM emission standards.In the case of envisaged serial application subject to emission standards like US Tier 2 and EU6, much work is still required in terms of system robustness and life. In higher-class vehicles, the NOx reduction potential is lower, and it will be more difficult to make do without NOx treatment, especially with ...
Deregulation of the electric power industry in Alberta holds the prospect of providing greater choice for customers. One such option will be `green power` which is provided by renewable energy technologies. The energy produced would be without environmental impacts such as air emissions, water pollution, flooding, thermal emissions or waste by-products. Wind power, small scale hydro power, photovoltaics and biomass technologies have been termed as `green power`. The choices that customers make will not be focused on price alone. Market forces are emerging to demand reduction in emissions which will result in a market for `green energy` products and facilitate achieving goals for a sustainable future.
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.
The problem of spectra formation in hydrodynamic approach to A+A collisions is discussed. It is analyzed in terms of the two different objects: distribution and emission functions. We show that though the process of particle liberation, described by the emission function, is, usually, continuous in time, the observable spectra can be also expressed by means of the Landau/Cooper-Frye prescription. We argue that such an approximate duality results from some symmetry properties that systems in A+A collisions reach to the end of hydrodynamic evolution and reduction of the collision rate at post hydrodynamic stage
An important aspect, which has to be considered in terms of municipal solid waste (MSW) management, is the stage of collection. The emissions generated from these systems can arrive to values that are of the same order of magnitude of emissions from combustion of waste in waste-to-energy plants. The present work faces the problem of transport, from intermediate station to the center of final combustion, placing attention to the emissions from scenarios that has been selected between real systems of management. This analysis can lead to highlight some important elements that can be useful to minimize the impacts.
The focus of this study is on the preparatory detection of uncertain net greenhouse gas (GHG) emission changes (also termed emission signals) under the Kyoto Protocol. The crucial question to be addressed is: How well do we need to know net emissions if we want to detect a specified emission signal after a given time? No restrictions exist as to what concerns the net emitter, which may be any GHG source or sink. Annex I countries are chosen as net emitters, simply for reasons of data availability and because of the excellent possibility of comparing net emitters (inter-country comparison). The countries' emissions - in an increasing number of cases even their uncertainties - are available permitting the application of preparatory signal detection techniques, which are suited to address the aforementioned question. We currently discuss four hierarchically-ordered detection ...
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.
Emission spectra obtained for three irradiated granular quartz samples under 1.43 eV excitation exhibited the 2.2 and 3.1 eV emission bands characteristic of feldspars. Excitation spectra of these same samples and several others show the 1.44 eV resonance typical of feldspars. This provides convincing evidence that the 2.2 and 3.1 eV infrared stimulated luminescence observed in these granular quartz samples arises from feldspar inclusions.
As part of a project to complete a comprehensive catalogue of astrophysically relevant emission lines in support of new-generation X-ray observatories using the Lawrence Livermore electron beam ion traps EBIT-I and EBIT-II, we studied emission lines of argon and sulfur in the soft X-ray and extreme ultraviolet region. Here we present observations of Ar IX through Ar XVI and S VII through S XIV between 20 and 75 {angstrom} to illustrate our work.
This paper presents an analysis of the performance of a selective emitter using small particles of rare earth compounds stable at high temperatures in a low emittance inert gas stream. An expression for the spectral emissive power excluding radiation scattering was derived to include the radiation in the emission band, produced by electronic transitions of the rare earth ion, and the continuum radiation outside the emission band produced by the rare earth host. Preliminary results suggest that a selective emitter based on suspended rare earth oxide particles will have high efficiency and merits further experimental investigation. {copyright} {ital 1996 American Institute of Physics.}
The possibilities of using both selective heavy ion induced X-ray emission and secondary ion mass spectroscopy (SIMS), for the identification of impurities present at low concentrations in cadmium telluride are examined. The relative concentrations of the impurities along CdTe crystals have been determined by exciting the X-ray emission of the elements in several slices with Ar and Kr ions and by comparing the relative characteristic X-ray emission yields. As a consequence of the quasimolecular inner shell ionization mechanism in heavy ion-atom collisions, Ar and Kr ions allow a strong excitation of the main impurities seen by SIMS namely Si, Cl and Ge, As, with only a minor contribution of Cd and Te. From the changes of the concentrations of the various impurities along the crystal, informations about segregation coefficients and compensation can be obtained.
This perspective view of Venus, generated by computer from NASA's Magellan data and color-coded with emissivity, shows part of the lowlands to the north of ...
The Toxicological Evaluation of Realistic Emissions of Source Aerosols (TERESA) study involved withdrawal, aging, and atmospheric transformation of emissions of three coal-fired power plants. Toxicological evaluations were carried out in rats exposed to different emission scenarios with extensive exposure characterization. Data generated had multiple levels of resolution: exposure, scenario, and constituent chemical composition. Here, we outline a multilayered approach to analyze the associations between exposure and health effects beginning with standard ANOVA models that treat exposure as a categorical variable. The model assessed differences in exposure effects across scenarios (by plant). To assess unadjusted associations between pollutant concentrations and health, univariate analyses...
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...
The purpose of this statement of work (SOW) is to establish laboratory analytical criteria and requirements for radioactive airborne emissions measurement sample and/or analysis activities.
Performance and emissions data were gathered on a normally aspirated single cylinder DI engine with various combinations of ceramic coatings installed. Thin ceramic thermal barrier coatings were applied to the piston crown and bowl, the head and valves, and the cylinder liner. The coated piston and head were run singly and in combination with the cylinder liner to investigate the effects of these different coated surfaces on emissions and performance. Coating the piston crown alone results in generally lower cylinder pressure, lower brake specific fuel consumption and lower NO(x) emission compared to the baseline engine. Soot emission is typically increased below 2000 RPM and decreased above 2000 RPM. Coating the head alone reduces cylinder pressure, but generally increases specific fuel consumption and NO(x) and soot emission. The KIVA-II code was used to model the Hydra engine ...
Corrosion of steam generator heat transfer tubes (SGHTT) is one of the important problems which affect safety operation of nuclear power plants (NPP), and the hazard of pitting corrosion of heat transfer tubes is the most serious. With an acoustic emission device, the signals during a corrosion test on SGHTT were collected and analyzed, and the corrosion points in the tubes were located accurately. The results show that pitting corrosion of heat transfer tubes has passed through three periods in its development: expansion phase, stationary phase and rapid developing phase. The corrosion damage of HTT can be found earlier with acoustic emission than any other non-destructive testing methods. Acoustic emission can be used for on-line and real-time monitoring of the safety and operation of the steam generator and has therefore a great significance. (orig.)
Global climate policy initiatives are now being proposed to compensate tropical forest nations for reducing carbon emissions from deforestation and forest degradation (REDD). These proposals have the potential to include developing countries more actively in international greenhouse gas mitigation and to address a substantial share of the world's emissions which come from tropical deforestation. For such a policy to be viable it must have a credible benchmark against which emissions reduction can be calculated. This benchmark, sometimes termed a baseline or reference emissions scenario, can be based directly on historical emissions or can use historical emissions as input for business as usual projections. Here, we review existing data and methods that could be used to measure historical deforestation and forest degradation reference scenarios including ...
Global climate policy initiatives are now being proposed to compensate tropical forest nations for reducing carbon emissions from deforestation and forest degradation (REDD). These proposals have the potential to include developing countries more actively in international greenhouse gas mitigation and to address a substantial share of the world's emissions which come from tropical deforestation. For such a policy to be viable it must have a credible benchmark against which emissions reduction can be calculated. This benchmark, sometimes termed a baseline or reference emissions scenario, can be based directly on historical emissions or can use historical emissions as input for business as usual projections. Here, we review existing data and methods that could be used to measure historical deforestation and forest degradation reference scenarios including FAO ...
This paper summarizes the main features of four current REDD proposals: Compensated Reduction, Papua New Guinea et al; Joint Research Center; and Brazil. ... ...
The influence of engine operating variables on the performance, emissions and heat release in a compression ignition engine operating in normal diesel and dual-fuel modes (with natural gas fuelling) was investigated. Substantial reductions in NO{sub x} emissions were obtained with dual-fuel engine operation. There was a corresponding increase in unburned hydrocarbon emissions as the substitution of natural gas was increased. Brake specific energy consumption decreased with natural gas substitution at high loads but increased at low loads. Experimental results at fixed pilot injection timing have also established the importance of intake manifold pressure and temperature in improving dual-fuel performance and emissions at part load. (Author)
The factors influencing premixed burning and the importance of premixed burning on the exhaust emissions from a small high-speed direct-injection diesel engine were investigated. The characteristics of premixed and diffusion burning were examined using a single-zone heat-release analysis. The mass of fuel burned in premixed combustion was found to be linearly related to the product of engine speed and ignition-delay time and to be essentially independent of the total amount of fuel injected. Accordingly, the premixed-burned fraction increased with increasing engine speed, with decreasing fuel-air ratio and with retarding injection timing. The hydrocarbon emissions did not correlate well with the premixed-burned fraction. In contrast, the oxides of nitrogen emissions were found to increase with decreasing premixed-burned fraction, indicating that diffusion burning, and not premixed burning, is the primary source of oxides of ...
NEWTON's first law prohibits the coupling of free tachyons to ordinary matter, if it is interpreted as selection rule interdicting emission without change of the rest-mass of the emitting system.
This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The authors investigated the evolution and radiation characteristics of individual neutron stars and stellar systems. The work concentrated on phenomena where new techniques and observations are dramatically enlarging the understanding of stellar phenomena. Part of this project was a study of x-ray and gamma-ray emission from neutron stars and other compact objects. This effort included calculating the thermal x-ray emission from young neutron stars, deriving the radio and gamma-ray emission from active pulsars and modeling intense gamma-ray bursts in distant galaxies. They also measured periodic optical and infrared fluctuations from rotating neutron stars and search for high-energy TeV gamma rays from discrete celestial sources.
(e.g. enclosed cooktop with built in emissions capture and treatment) . " Test hardware in laboratory, reduced pressure and analog habitat. " Objective 1. ...
Divergence betyveen aircraft engine emission regulations pro- posed by EPA and ICAO is discussed Every engine, upon entering service, requires a certificate ...
We have studied the nature of continuum emitted in the visible spectral range from a noncontracted positive column of discharge in a cesium vapor-xenon mixture at a pressure of 45 Torr and at a degree of ionization below 3 ? 10?6. The main contribution to the continuous emission under such conditions is due to electron-xenon atom bremsstrahlung. The intensity of emission has been experimentally and theoretically studied as a function of the electric field strength and electron density in the positive column. It is established that an increase in the visible emission intensity with the electric field strength is related to an increase in the number of hot electrons in plasma.
This paper reports extensive new optical and radio observations of NGC 5728, emphasizing the central regions. Deep photographs revealing detail in the faint spiral arms are briefly discussed. Broad-band UBV CCD images obtained to examine the colors of the stellar populations that comprise the bar and central ring are presented. The velocity field and emission maps obtained from imaging spectroscopic measurements in the H-alpha emission line are discussed. Conventional long-slit spectra covering the ionized gas in the nuclear region are described. Detailed maps of the radio emission in the central regions of NGC 5728 are presented. These combined data provide considerable evidence for the inflow of gas into the nuclear region, in response to the nonaxisymmetric gravitational potential of the bar. The possible relation of this phenomenon to the Seyfert nature of NGC 5728 is also considered. 48 references.
We report novel, high-angular resolution interferometric measurements that imply the near-infrared nuclear emission in NGC 4151 is unexpectedly compact. We have observed the nucleus of NGC 4151 at 2.2 microns using the two 10-meter Keck telescopes as an interferometer and find a marginally resolved source ~0.1 pc in diameter. Our measurements rule out models in which a majority of the K band nuclear emission is produced on scales larger than this size. The interpretation of our measurement most consistent with other observations is that the emission mainly originates directly in the central accretion disk. This implies that AGN unification models invoking hot, optically thick dust may not be applicable to NGC 4151.
Ceramic coatings with high emission were fabricated on Ti6Al4V alloy by microarc oxidation (MAO) with additive FeSO4 into the electrolyte. The microstructure, chemical composition and chemical state of the coatings were determined by SEM, XRD, EDS and XPS, respectively. The bonding strength between the coating and substrate was studied by tensile strength test, together with the thermal shock resistance of the coating. The results showed that Fe content in the coating layer significantly affect its thermal emissivity. The relative content of Fe in the coatings surface increased at first and then decreased with increasing the concentration of FeSO4 in electrolytes, so does the emissivity of the coatings. The bonding strength became weaker with increasing the concentration of FeSO4. In addit...
The Kyoto Protocol attempts through political negotiations to guide participating industrialized countries' greenhouse gas (GHG) emissions from a positive growing trend, to reach a peak point (or turning point), and then be reduced to a negative growth. That means the relationship between decreasing GHG emissions and economic growth may be described by an inverted-U curve (or called a bell-shaped curve), which is consistent with the concept of the Environmental Kuznets Curve (EKC) hypothesis.This research observed that the economic development and GHG emissions in Economies in Transition (EITs) exhibit a hockey-stick curve trend (or called quasi-L-shape curve), that also generates a lot of "hot air" which is significant to the implementation of the Kyoto Protocol. In addition, through the ...
... non- emissive guidance and collision alert, automated transport in dynamic environments, and assembly and inspection. Foveal Vision, Autonomous Agents, ...
Biomass combustion is an important part in a sustainable energy system, but as well a source of submicron (particles < 1 #mu#m) particles in the air. Consequently, to obtain a good air quality together with increased biomass combustion there is a need for a better understanding of particle formation. This work is a part of a larger project about formation and emissions of particles from biofuel combustion. The report includes the work performed in the project during the year 2004. The aim of the project is to describe the release of inorganic components, which cause particle emissions, during combustion of single fuel particles of biofuel, e.g. wood pellets. The work is carried out by emission measurements, systematic combustion experiments and modelling work. The results are expected to contribute to the understanding of which parameters that influence the formation of fine particles and thus gain a better insight into ...
The report contains general information on aluminium and aluminium compounds concerning the existing standards, emissions, exposure levels and effect levels. The document is to be considered as a first evaluation to be used for the national discussion dur...
The iron foundry industry is considered to be a potential source of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). This study investigated the emission factors and total emission amounts of PCDD/Fs and dioxin-like polychlorinated biphenyls (DL-PCBs) from iron foundries in China. The concentrations and the World Health Organization toxicity equivalents (WHO-TEQs) are presented and the congener profiles are discussed in this paper. In the present work, 26 fly ash samples were collected and tested to quantify the PCDD/Fs and DL-PCBs generated by 14 plants of different scales, and five stack gas samples were collected from two (named as EFG and LFG) of those plants. The emission levels of PCDD/Fs and DL-PCBs indicated that hot-air cupolas had lower emissions than cold-air cupol...
The paper discusses a number of recent studies investigating into the energy conservation and environmental impacts of electric heating systems (off-peak storage systems). In future, i.e. in and after 1993, off-peak storage systems will be evaluated through comparative analyses of oil-fired heating systems, pollutant emission analyses, the eventual success of pollution abatement measures designed for power plant emissions to keep within the legal limiting values, and the possible abandonment of pollution abatement measures abroad. Opposing the electric heating studies submitted by the electric power industry the author refutes their favourable results referring to the palliative selection of inadequate or vague parameters. Assuming average power plant pollutant emissions of 180 mg/standard/sup 3/ the nitrogen oxide emissions of oil-fired heating systems (134.1 kg/Tj) are found to be below those of ...
Before the 1997 Kyoto Protocol on Climate Protection, the fluorinated greenhouse gases HFCs, PFCs, and SF6 (F-gases) aroused little public attention. Since then, the standards on surveying and reporting on national emissions have been rising constantly. Amongst others, the annual reporting to the UNFCCC secretariat makes detailed declarations on use and emissions of F-gases necessary, which have to be filled in specified formats for submission (Common Reporting Format = CRF). The scientific basis has been set out by the UNFCCC guidelines on reporting, in accordance with the instructions laid down in IPCC good practice guidance. Additionally, in Germany the Centralised System of Emissions (ZSE) shall provide a suitable tool to satisfy any quality needs of both activity data and emission factors. From 1995 onwards, activity data and emissions of each individual application sector ...
Los Alamos National Laboratory (the Laboratory) is subject to emissions reporting requirements for regulated air contaminants under Title 20 of the New Mexico Administrative Code, Chapter 2, Part 73 (20 NMAC 2.73), Notice of Intent and Emissions Inventory Requirements. The Laboratory has the potential to emit 100 tons per year of suspended particulate matter, nitrogen oxides, carbon monoxide, sulfur oxides, and volatile organic compounds. For 1998, combustion products from the industrial sources contributed the greatest amount of criteria air pollutants from the Laboratory. Research and development activities contributed the greatest amount of volatile organic compounds. Emissions of beryllium and aluminum were reported for activities permitted under 20 NMAC 2.72 Construction Permits.
Although various legislation and regulations have been adopted to promote the use of alternative-fuel vehicles for curbing urban air pollution problems, there is a lack of systematic comparisons of emission control cost-effectiveness among various alternative-fuel vehicle types. In this paper, life-cycle emission reductions and life-cycle costs were estimated for passenger cars fueled with methanol, ethanol, liquefied petroleum gas, compressed natural gas, and electricity. Vehicle emission estimates included both exhaust and evaporative emissions for air pollutants of hydrocarbon, carbon monoxide, nitrogen oxides, and air-toxic pollutants of benzene, formaldehyde, 1,3-butadiene, and acetaldehyde. Vehicle life-cycle cost estimates accounted for vehicle purchase prices, vehicle life, fuel costs, and vehicle maintenance costs. Emission control cost-effectiveness presented in dollars ...
The properties of negative-ion beams are very important for designing negative-ion apparatus and applications of negative-ion beams, especially, electron detachment cross-sections at the interaction between negative-ion beams and gas particles in the transport system, and secondary-electron emission factors when negative ions are incident on solid surfaces. These properties of negative-ion beams were investigated experimentally as a function of the ion energy under 50 keV. The single electron detachment cross-sections are almost constant in the other of 10[sup -15] cm[sup 2] in this energy range, but double electron detachment cross-sections increase in proportion to the ion velocity and much smaller than the single one. As for the secondary-electron emission factor, the emission factors for negative-ion beam are found to be larger by 1 than those for positive-ion beams. (author).
The properties of negative-ion beams are very important for designing negative-ion apparatus and applications of negative-ion beams, especially, electron detachment cross-sections at the interaction between negative-ion beams and gas particles in the transport system, and secondary-electron emission factors when negative ions are incident on solid surfaces. These properties of negative-ion beams were investigated experimentally as a function of the ion energy under 50 keV. The single electron detachment cross-sections are almost constant in the other of 10"-"1"5 cm"2 in this energy range, but double electron detachment cross-sections increase in proportion to the ion velocity and much smaller than the single one. As for the secondary-electron emission factor, the emission factors for negative-ion beam are found to be larger by 1 than those for positive-ion beams. (author).
Experiments have been conducted to study the effect of injection pressure on the combustion process and exhaust emissions of a direct injection diesel engine fueled with Orange Skin Powder Diesel Solution (OSPDS). Earlier investigation by the authors revealed that 30% OSPDS was optimum for better performance and emissions. In the present investigation the injection pressure was varied with 30% OSPDS and the combustion, performance and emissions characteristics were compared with those of diesel fuel. The different injection pressures studied were 215bar, 235bar and 255bar. The results showed that the cylinder pressure with 30% OSPDS at 235bar fuel injection pressure, was higher than that of diesel fuel as well as at other injection pressures. Similarly, the ignition delay was longer and wi...
This standard specifies requirements for the flameproofing and the limiting of surface temperature and exhaust emission control of diesel engine systems for use in underground coal mines.
The work described in the following is a portion of the MEET project (Methodologies for Estimation Air Pollutant Emissions from Transport). The overall goal of the MEET project is to consolidate and present methodologies which can be used to estimate air pollutant emissions from various types of traffic sources. One of the goals of MEET is to provide methodologies to be used in the COMMUTE project also funded by DG VII. COMMUTE is developing computer software which can be used to provide emissions inventories on the European scale. Although COMMUTE is viewed as a prime user of the information generated in MEET, the MEET results are intended to be used in a broader area, and on both smaller and larger spatial scales. The methodologies and data presented will be useful for planners on a more local scale than a national or continental basis. While most attention in previous years has been concentrated on ...
... 1-sigma ZOHF pixel-to-plxel statistical fluctuations ... Spatial frequency filtering shows distinct bands, but miss ... LOS emissivity at the point of closest ...
Fire-driven deforestation is the major source of carbon emissions from Amazonia. Recent expansion of mechanized agriculture in forested regions of Amazonia ...
on the range of available deforestation, forest degradation, ... Results: Deforestation estimates showed good agreement for multi-year trends of increasing ...
We introduced a probability of traffic light, PL, at an intersection when approaching cars in two roads are in same conditions. As a application, we proposed a modified Nagel-Schreckenberg cellular automata model for describing a conflicting vehicular traffic flow at the intersection. The results show that the plateau region in the fundamental diagrams, caused by the effect of interaction, is dependent not only on the probability PL, but also on the adaptive schemes.
MOX fuel has been one of the mature nuclear fuels which can be used in light water nuclear power plant now. The development status in this domain in foreign countries, the major influence of MOX fuel on reactor performance and the countermeasures are introduced in this paper. The application of MOX fuel in China's PWR is discussed in the end. (authors)
The report gives results of a second survey of the flue gas desulfurization (FGD) system on Unit 1 of Kansas City Power and Light Co.'s La Cygne Station. The FGD system, first started up in February 1973 and commercially available in June 1973, uses a lim...
The report gives results of a survey of the flue gas desulfurization (FGD) systems at Kansas Power and Light Co.'s Lawrence Power Station. The systems utilize boiler injection of pulverized limestone, followed by tail-end wet scrubbing: unit 4, with a net...
The report gives results of a survey of the flue gas desulfurization (FGD) systems at Kansas City Power and Light Co.'s Hawthorn Power Station. The FGD systems on Hawthorn boilers 3 and 4 were designed to operate by injection of dry limestone in the boile...
... The composite ground floor is suitable for support to all types of wall construction and can be used equally well on strip footings or mini-pile foundations . The light steel edge beams provide the accurate template required for internal timber or light steel wall frames to minimise fitting time and eliminate rework. The floated slab surface will accept floor finishes directly and thermal insulation can be easily fitted beneath ...
Reflective diffraction grating. A focused ion beam (FIB) micromilling apparatus is used to store color images in a durable medium by milling away portions of the surface of the medium to produce a reflective diffraction grating with blazed pits. The images are retrieved by exposing the surface of the grating to polychromatic light from a particular incident bearing and observing the light reflected by the surface from specified reception bearing.
Most diffusion phenomena in solids can be understood (or sometimes misunderstood) on a purely classical model. For light interstitials (hydrogen isotopes, the positive muon, and potentially He) there may be anomalous temperature dependences, and isotope effects, and anomalous response to electric fields and temperature gradients. Some of these anomalies are quantal in origin, and will be discussed. (author).
A possibility of generating collimated beams of faster-than-light particles (tachyons) and using them for rocket propulsion is explored. The relativistic rocket equations are derived, and are solved for a single-stage rocket with constant mass flow rate, constant exhaust velocity and no coasting period. The features of these solutions for faster-than-light exhaust velocities are discussed. It is shown that a tachyon drive would not violate the first law of thermodynamics. However, as seen in the Galactic frame, it would violate the second law.
Described herein is an optical probe (120) for use in characterizing surface defects in wafers, such as semiconductor wafers. The optical probe (120) detects laser light reflected from the surface (124) of the wafer (106) within various ranges of angles. Characteristics of defects in the surface (124) of the wafer (106) are determined based on the amount of reflected laser light detected in each of the ranges of angles. Additionally, a wafer characterization system (100) is described that includes the described optical probe (120).
Most antibodies to factor VIII have recently been shown to react with discrete regions of the factor VIII light chain (within the C2 domain) and/or the factor VIII heavy chain (within the amino-terminal...Full Text Available
A two-beam spectroscopy (TBS) system is evaluated theoretically and experimentally. This new spectroscopic technique uses correlations between components of emitted light separated by a small difference in angle of propagation. It is thus a non-perturbing plasma diagnostic which is shown to provide local (as opposed to line-of-sight averaged) information about fluctuations in the density of light sources within a plasma - information not obtainable by the usual spectroscopic methods. The present design is an improvement on earlier systems proposed in a thesis by Rostler.
This standard addresses the design bases for light water reactor, nuclear power plant structures and components essential for the protection of public health and safety from the potential adverse effects of pipe whip, jet impingement, pressurization of compartments outside containment, environmental conditions and flooding associated with a postulated pipe rupture. The design bases for missile protection and the design bases for containment pressurization are not within this standard.
This standard addresses the design bases for light water reactor, nuclear power plant structures and components essential for the protection of public health and safety from the potential adverse effects of pipe whip, jet impingement, pressurization of compartments outside containment, environmental conditions and flooding associated with a postulated pipe rupture. The design bases for missile protection and the design bases for containment pressurization are not within this standard.
This report discusses a desk-top computer program has been developed for estimating the costs, waste volumes, and occupational radiation exposures associated with decommissioning light-water reactor power stations. Cost categories and cost algorithms used in the program are discussed and a brief description of the user interface is given.
Ultraviolet light can be used to immobilize biomolecules onto thiol reactive surfaces in order to, e.g., make biosensors. The mechanism involves light-induced formation of free, reactive thiol groups in disulphide containing molecules. This technology allows for the creation of arrays of biomolecules with a high degree of reproducibility, circumventing the need for often expensive nano/micro-dispensing technologies. The ultimate size of the immobilized spots is defined by the focal area of the UV beam. Light-induced immobilization has the added benefit that the immobilized molecules will be spatially oriented and covalently bound to the surface. In this paper, we demonstrate the utility of a sensor array created with the new sensor technology when integrated into a microfluidic system. Protein arrays made using light-induced immobilization showed successful antigen/antibody binding in a flow cell ...
A novel visible light sensitive photocatalyst, AgSbO3 was prepared by a conventional solid-state reaction method. This oxide belonging to a cubic-pyrochlore structure can absorb visible light with wavelength up to about 480nm. From the band structure calculation, we found that the top of the valence band consists of the hybridized Ag 4d and O 2p orbitals and the bottom of the conduction band mainly consists of the Ag 5s and the Sb 5s orbitals. Photocatalytic activities were evaluated using O2 evolution from an aqueous silver nitrate solution and decomposition of gaseous 2-propanol under visible light irradiation. We found that AgSbO3 shows a higher O2 evolution activity than WO3 and 2-propanol can be mineralized by the AgSbO3 photocatalysis under visible light irradiation.
Endoreduplication represents a cell cycle variant during which multiple rounds of DNA replication occur without subsequent chromosome separation and cytokinesis, resulting into a cellular increase of the DNA content. Although the DNA ploidy level of cells is controlled by external stimuli such as light, currently limited knowledge is available on how environmental signals regulate the endoreduplication cycle at the molecular level. Previously, we have demonstrated that the conversion from the mitotic cell cycle into an endoreduplication cycle is mediated by the atypical E2F transcription factor DEL1 that operates as a repressor of endocycle onset. Here, we identified DEL1 as a transcriptional target of the classical E2Fb and E2Fc transcription factors that antagonistically control DEL1 transcript levels through competition for a single E2F cis-acting binding site. Correspondingly with the reported opposite effect of light on the E2Fb and E2Fc ...
The University of Georgia, in collaboration with GE Global Research, has investigated the relevant quenching mechanism of phosphor coatings used in white light devices based on UV LEDs. The final goal of the project was the design and fabrication of a high-efficacy white light UV-LED device through improved geometry and optimized phosphor coatings. At the end of the research period, which was extended to seamlessly carry over the research to a follow-up program, we have demonstrated a two-fold improvement in the conversion efficiency of a white light LED device, where the increase efficacy is due to both improved phosphor quantum efficiency and lamp geometry. Working prototypes have been displayed at DOE sponsored meetings and during the final presentation at the DOE Headquarters in Washington, DC. During the first phase of the project, a fundamental understanding of quenching processes in UV-LEDs was obtained, and the ...
The University of Georgia, in collaboration with GE Global Research, has investigated the relevant quenching mechanism of phosphor coatings used in white light devices based on UV LEDs. The final goal of the project was the design and fabrication of a high-efficacy white light UV-LED device through improved geometry and optimized phosphor coatings. At the end of the research period, which was extended to seamlessly carry over the research to a follow-up program, we have demonstrated a two-fold improvement in the conversion efficiency of a white light LED device, where the increase efficacy is due to both improved phosphor quantum efficiency and lamp geometry. Working prototypes have been displayed at DOE sponsored meetings and during the final presentation at the DOE Headquarters in Washington, DC. During the first phase of the project, a fundamental understanding of quenching processes in UV-LEDs was obtained, and the ...
'Within 15 years the energy consumption bottleneck has shifted from the supply side to emissions, i.e. to the waste side.' Reflecting this statement one may realize the importance of lending more weight to energy conservation but may also be induced to critically analyze the corresponding measures. First results of such reflections are given with regard to the payback periods of air pollution abatement measures relative to the additional emissions they cause. (orig.).
Lectures were held on forest and wood management, the forest as an energy source and the emission problem of wood combustion, future emission limitating regulations for wood firing, influence of firing technique on air pollution abatement and constructive and operational air pollution abatement measures with manually and continuously fuelled furnaces.
In this work, the principal continuum radiative emission processes, which occur during the penetration of ions in solids or gases, are resumed. The characteristics of the following processes are discussed: secondary electron bremsstrahlung (SEB), atomic bremsstrahlung (AB), and internuclear bremsstrahlung (INB). Recent advances of the ion channeling effects in crystal solids on the spontaneous radiative spectra are exposed. (A.C.A.S.).
In February 2001, the Minister of Environment Canada outlined a series of measures to be implemented over the next decades to reduce emissions from vehicles, engines and fuels. The agenda includes the development of new regulations under the authority of Part 7, Division 5 of the Canadian Environmental Protection Act (CEPA) to align Canada's emission standards for on-road vehicles with those of the United States Environmental Protection Agency. This paper presents a detailed summary of comments received by the interested parties that appeared at a public consultation in November 2001 to discuss and raise issues about the proposed regulations. The parties that provided submissions included: governments; the vehicle and engine manufacturing industry; the oil industry; other groups of associations such as the Canadian Trucking Alliance, David Suzuki Foundation, and West Coast Environmental Law; and, five private individuals. The report ...
In response to a need of the safeguards community, we have begun an evaluation effort to upgrade the recommended values of the prompt neutron emission multiplicity distribution, P/sub nu/ and its average value, nubar. This paper will report on progress achieved thus far. The evaluation of the uranium, plutonium, americium and curium nuclide's nubar values will be presented. The recommended values will be given and discussed. 61 references.
It is shown that low-frequency elastic vibrations of near-surface planar defects cause high-frequency ultrasonic radiation in surrounding air. The frequency conversion mechanism is concerned with contact nonlinearity of the defect vibrations and provides efficient generation of air-coupled higher-order ultraharmonics, ultrasubharmonics, and combination frequencies. The nonlinear air-coupled ultrasonic emission is applied for location and high-resolution imaging of damage-induced defects in a variety of solid materials.
The present work reports an experimental study on the behavior of a jet flame surrounded by a shroud of combustion air. Measurements focussed on the flame length and the emissions of NO{sub x}, total unburned hydrocarbons, CO{sub 2}, and O{sub 2}. Four different fuel flow rates (40.0, 78.33, 138.33, and 166.6 cm/s), air flow rates up to 2500 cm{sup 3}/s and four different air injector diameters (0.079 cm, 0. 158 cm, 0.237 cm, and 0.316 cm) were used. The shroud of combustion air causes the flame length to decrease by a factor proportional to 1/[p{sub a}/p{sub f} + C{sub 2}({mu}{sub a}Re,a/{mu}{sub f}Re,f){sup 2}]{sup {1/2}}. A substantial shortening of the flame length occurred by increasing the air injection velocity keeping fuel rate fixed or conversely by lowering the fuel flow rate keeping air flow rate constant. NO{sub x} emissions ranging from 5 ppm to 64 ppm were observed and the emission of NO{sub x} decreased ...
The Clean Air Act establishes New Source Review (NSR) programs that apply to the construction or modification of major stationary emissions sources. In 2002 and 2003, the U.S. Environmental Protection Agency revised its rules to narrow the applicability of NSR to facility renovations. Congress then mandated a National Research Council study of the effects of the rules. An electricity-sector model - the Integrated Planning Model (IPM) - was used to explore the possible effects of the equipment replacement provision (ERP), the principal NSR change that was to affect the power-generation industry. The studies focused in particular on coal-fired electricity generating units, EGUs, for two reasons. First, coal-fired EGUs are important contributors of these pollutants, accounting for approximately 70 and 20% of nations SO{sub 2} and NOx emissions in 2004, respectively. Second, the shares of total capacity of large coal-fired EGUs that lack flue-gas ...
Auger-electron emission from different silicides has been studied for 4 and 10 keV Ar ion excitation. The intensity of the SiLMM Auger line changes significantly with channing concentration and atomic number of the metal-parthner. The experimental results can be explained in terms of a simple model based on the probability of Si-Si collision symmetric cascade in these binary compounds.
In this report statistical data are presented on a national level on emissions to air in Sweden in 1995 of sulphur dioxide (SO{sub 2}), nitrogen oxides (NO{sub x}, counted as NO{sub 2}) and carbon dioxide (CO{sub 2}). Corresponding data for 1980 and 1994 are presented as a comparison. For CO{sub 2} data for 1990 and 1994 are presented as a comparison. The total amount of SO{sub 2}-emissions to air in 1995 were 94 000 tons, which means a decrease by 3 percent since 1994. The total amount of NO{sub x}-emissions to air were 362 000 tons, a 3 percent decrease since 1993. The total amount of CO{sub 2}-emissions to air were 63 200 000 tons, an increase by 7 percent compared with 1990. Differentiated data are given for various sources of emissions, i.e. combustion of fuels, industrial processes and mobile sources. Further data are presented on emission of SO{sub 2} and ...
Experiments have been conducted to study the effect of injection pressure on the combustion process and exhaust emissions of a direct injection diesel engine fueled with Orange Skin Powder Diesel Solution (OSPDS). Earlier investigation by the authors revealed that 30% OSPDS was optimum for better performance and emissions. In the present investigation the injection pressure was varied with 30% OSPDS and the combustion, performance and emissions characteristics were compared with those of diesel fuel. The different injection pressures studied were 215 bar, 235 bar and 255 bar. The results showed that the cylinder pressure with 30% OSPDS at 235 bar fuel injection pressure, was higher than that of diesel fuel as well as at other injection pressures. Similarly, the ignition delay was longer and with shorter combustion duration with 30% OSPDS at 235 bar injection pressure. The brake thermal efficiency was better at 235 bar than ...
Due to the 'novel forest diseases' the political parties of the Federal Republic of Germany unanimously attend to the reduction of emissions. The transportation sector is considered to be a major emission source. A study discussed in the publication abstracted did therefore aim at giving a detailed account and description of the recently ratified technical requirements and tax credits expected to reduce vehicle exhaust gas air pollution. Moreover, the study researches into the regulations' importance as to the low emission properties of individual automobiles. Based on the results obtained the study arrives at assumptions as to emissions to be expected from the transportation sector. It tries to assess the financial import with respect to the individual citizen, overall internal revenues and federal motor vehicle taxes. The introductory chapter is followed by a review of ...
A large IMF- and event characterizing multidetector system (CHICSI) is under development for storage ring experiments. In ''test'' experiments with telescopes of CHICSI type the IMF production has been measured for "1"4N induced reactions at 14A and 32A MeV. Detailed information about the emission sources, particularly from the IMF yield in reactions with isotope separated targets and from isobaric yield ratios in the sub-Coulomb region is discussed. (orig.).
This study presents and applies a coherent methodological framework to compare biomass cascading chains, i.e. the subsequent use of biomass for materials, recycling and energy recovery, considering land use, CO2 emission reduction and economic performance. Example cascading chains of short rotation poplar wood are compared with each other on the basis of literature data. Results for these chains vary strongly, namely, from CO2 mitigation benefits of 200 euro/Mg CO2 to CO2 mitigation costs of 2200 euro/Mg CO2, and from net CO2 emission reductions per hectare of biomass production of 28 Mg CO2/(ha yr) to net CO2 emissions of 8 Mg CO2/(ha yr). Using a present-value approach to determine CO2 emissions and costs affects the performance of long-term cascading chains significantly, i.e. cost and CO2 emission reduction are decreased. In general, cascading has the potential to improve both ...
This paper describes New York State Electric and Gas Corporation`s concept for a comprehensive, centrally located data system for management of their continuous emission monitoring systems (CEMS) data. The topics of the paper include the power system`s mix of generating units; data reporting requirements; data base management; nitrogen oxides compliance tracking; sulfur dioxide, nitrogen oxides, carbon dioxide and flow monitoring; and allowance tracking.
Characterization and optimization of electron-beam parameters are important aspects of optimizing free-electron laser (FEL) performance. The visible spontaneous emission ({lambda}{approximately}650 nm) from the 5-meter long undulator of the Boeing FEL experiment can be characterized in sufficient detail with a streak/spectrometer to deduce time-resolved electron-beam spatial position and profile, micropulse duration, and energy. 7 refs., 13 figs., 2 tabs.
Discussion is presented of world CO{sub 2} emissions and the effect rising population and population distribution has on this. Possible ways of decreasing emissions are presented, including potential for heat recovery, exhaust-air purification as an energy supply, shared power supply in industry, the use of cogeneration, and multiple use of heat in industry. 9 refs., 10 figs., 3 tabs.
We derive the expression for spontaneous emission rate in finite one-dimensional photonic crystal with arbitrary defects using the effective resonator model to describe electromagnetic field distributions in the structure. We obtain explicit formulas for contributions of different types of modes, i.e. radiation, substrate and guided modes. Formal calculations are illustrated with a few numerical examples, which demonstrate that the application of effective resonator model simplifies interpretation of results.
In the last issue of 'L'Industrie ceramique et verriere', we presented the first part of this study. We describe in this issue the experimental procedure, the results and the conclusions of this work. (authors)
The paper investigates the controversial relation between the continuum luminosity and the C IV 1550 emission-line strength in the spectra of quasars, commonly referred to as the Baldwin effect, as a possible indicator of absolute luminosity. It is concluded that the Baldwin effect does represent a physical correlation between the continuum and the C IV 1550 equivalent width rather than a consequence of selection effects. In addition to the C IV results, a similar relation is found for the Lyman-alpha emission line. 38 refs.
This paper reviews three key initiatives undertaken in the historical city of Oxford to bring about reductions in energy-related CO_2 emissions on a city-wide scale. The author has been part of all the three initiatives. In 2002, a collaborative partnership between academia, industry and city council started the Oxford Solar Initiative (OSI) which uses a community-based approach to help households and organisations in Oxford, financially and technically, to install solar energy systems and energy efficiency measures in buildings. So far OSI has facilitated the installation of 80 active solar systems, over 450 energy efficiency measures and 3,000 low energy bulbs. The scientific basis of OSI is a GIS-based DECoRuM model which estimates and maps baseline energy use and CO_2 emissions on a house-by house level, identifies 'pollution' hotspots, predicts the potential for reductions in CO_2 emissions and monitors reductions ...
The authors present design methodology and initial experimental results for a high power microwave switch. The switch is designed for application to the pulse compression system associated with the Next Linear Collider Test Accelerator (NLCTA). The switch is based on the excitation of a plasma layer within a silicon wafer by either a laser or an electron beam. They investigate problems associated with high power operation of such a switch. They explore solutions to the problems of thermal runaway, avalanche breakdown, photo-emission, and secondary emission.
This critical review with 28 references examines absorption and emission in the v2 band of the carbon dioxide molecule at around the 15micron wavelength. The argument for additional infrared absorption, the enhanced greenhouse effect due to increased carbon dioxide concentrations, and radiation transport and increased emissions are discussed. Experiments studying the transmission spectra of pure carbon dioxide and carbon dioxide in nitrogen, and comparing them with the results of climate modelling using the HITRAN and GEISA databases, are described.
Objectives~%~ To quantify the volatile organic compound (VOC) emissions arising from the composting of a range of municipal and~%~ industrial wastes.~%~~%~ To relate the VOC emissions to the material being processed and the process conditions.~%~~%~ To confirm the findings of the above activites by monitoring full-scale composting operations.~%~~%~ To develop predictive models of VOC emissions in relation to waste feedstock and process conditions.~%~~%~ To produce guidance for plant designers, operators a [continued...]DescriptionA recent study of three composting plants undertaken for the Environment Agency has confirmed earlier work suggesting that waste composting can be a source of volatile organic compound (VOC) emissions. However, these experiments were restricted to garden and kitchen waste composting schemes and it was not ...
It is necessary to establish scenarios for reducing CO2 emissions and for developing CO2 emission control technologies to obtain a global consensus, using appropriate analytical models. For modification of the DNE-21 (Dynamic New Earth 21) model, it has a category designated as innovative technologies not involving CO2 emission and an optional consideration for the absorption of atmospheric CO2 by biomass. A global carbon circulation model, including vegetation in its scope, is also incorporated. Major results of the simulation are shown. When 20% reduction in CO2 emissions is required for only OECD countries after the year 2020, it has been demonstrated that CO2 concentration in the atmosphere will reach as high as about 900 ppm in 2100 due to CO2 emission by developing countries, and will not be a tolerable level. Under the condition that CO2 concentration in the atmosphere is ...
We propose to investigate the spontaneous emission of radiation arising out of the interaction of a relativistic electron beam with a metallic grating (the Smith-Purcell effect). The work will concentrate, primarily, in the 50-120 #mu#m part of the infrared spectrum and will be an extension of the work begun by the Oxford-Dartmouth-Essex collaboration; one of the early objectives of the project will be to develop a quantitative understanding of the power spectrum of the emitted radiation over a wide range of emission angles. In particular, the limits of relativistic peaking of forward directed emission will be investigated. The electron beam will be produced by laser irradiation of a metallic cathode in the terminal of a small Van de Graff accelerator located in the Technische Universitaet, Muenchen. Beam energies will be in the range of 2 - 4 MeV. Initial tests on photoproduction of electrons have yielded 10 mA pulses with ...
In order to establish the optimum fueling in a natural gas fueled dual fuel engine, tests were made for some operational parameters and their combination on the engine performances and the exhaust emissions. The results show that the gas oil quantity should be increased and gas oil injection timing should be advanced to suppress unburned hydrocarbon emission at middle and low output range, while the quantity should be reduced and the timing should be retarded to avoid onset of knock at high loads. The unburned hydrocarbon emission and the thermal efficiency are improved at the same load avoiding too lean natural gas premixture by restriction of intake charge air. However the improvement is limited because the ignition and initial combustion of pilot diesel fuel is deteriorated when the cylinder pressure is excessively lowered by throttling. The increase in pilot gas oil amount is effective for low-load operation and the ...
We aim to obtain a consistent description of non-thermal emissions from Abell 2256 and to give a prediction for a gamma-ray emission from this galaxy cluster. Assuming that a radio relic illuminates a localization of an ongoing merger, and that both radio and non-thermal part of hard X-ray emission are due to electron component of cosmic rays filling the relic, we derived from radio and hard X-ray properties of the relic in A2256 the magnetic field strength and number densities for relativistic electrons and protons. Due to the interpretation of the radio relic as a structure formed just where a shock front is, we discuss a gamma-ray emission at the cluster periphery. The estimated strength of the magnetic field in the relic is equal to 0.05 \\muG, while the amplitude of the electron number density varies from 3 x 10^{-4} to 3 x 10^{-5} cm^{-3} (respectively for the relic thickness of 50 to 500 kpc). We ...
For a direct injection diesel engine to exhibit its inherent low-emission characteristics, it is essential to improve control accuracy, in particular under transient operating conditions during which emissions are more noted. A model-based control system is established for exhaust gas recirculation (EGR) and air/fuel ratio, using a diesel-engine/vehicle model established on the CAD control system. Described herein are the results of simulation for optimizing control of transient conditions, and the emission-controlling effects confirmed by the field tests. The tests for verification of the established model have confirmed that there are good agreements between the simulated and observed results in terms of air/fuel ratio changing with EGR ratio, exhaust and intake gas and pressure levels, and vehicle speed. The model will be applicable to assessment of emission characteristics under varying conditions. ...
A detailed assessment of the consumption of mercury, divided into use areas, was carried out. Disposal and emissions to the environment were also qualified. The assessment is mainly based on data from 1992 - 1993. The most important source of emission of mercury to air is solid waste incineration which is assessed in particular to be due to the supply of mercury in batteries (most likely mercury oxide batteries from photo equipment) and to dental fillings. The second most important source of mercury emission to air is coal-fired power plants which are estimated to account for 200-500 kg of mercury emission p.a. Other mercury emissions are mainly related to waste treatment and disposal. The consumption of mercury is generally decreasing. During the period from 1982/83 - 1992-93, the total consumption of mercury in Denmark was about halved. This development is related to the fact that ...
A hydrogen combustion and exhaust emissions in a supercharged gas engine ignited with micro pilot diesel fuel was discussed in this presentation. A schematic diagram of the experimental study was first presented. The single cylinder, water-cooled, supercharged test engine was illustrated. Results were presented for the following: fuel energy and energy share (hydrogen and diesel fuel); pressure history and rate of heat release; engine performance and exhaust emissions; effect of nitrogen dilution on heat value per cycle; effect of N_2 dilution on pressure history and rate of heat release; and engine performance and exhaust emissions. This presentation demonstrated that smooth and knock-free engine operation results from the use of hydrogen in a supercharged dual-fuel engine for leaner fuel-air equivalence ratios maintaining high thermal efficiency. It was possible to attain mor3 than 90 per cent hydrogen-energy substitution ...
The United Nations Framework Convention on Climate Change (UNFCCC) was approved in 1992 to respond to the worl-wide concern about the warming of the planet. The primary target was the stabilization of the concentration of greenhouse gases in the atmosphere, in an attempt to reduce to the minimum the degradation of the environment caused by humans. By virtue of the Convention, the Parts2 are committed to reach their objectives in the reduction of the emissions. A Conference of the Parts was stablished to promote the effective application of the Convention. The third Conference of the Parts, celebrated in Kyoto (Japan, 1997) approved, by consensus, the denominated Kyoto Protocol, in which 39 developed countries and countries with economies in transition were committed to reduce their emissions of greenhouse gases between years 2008 and 2012 in a 5.2 global percent with respect to the 1990 levels. Three {sup f}lexibility mechanisms{sup w}ere ...
Context: The colliding-wind binary Eta Car exhibits soft X-ray thermal emission that varies strongly around periastron, and non-thermal emission seen in hard X-rays and gamma-rays. Aims: To definitively identify Eta Car as the source of the hard X-ray emission, to examine how changes in the 2-10 keV band influence changes in the hard X-ray band, and to understand more clearly the mechanisms producing the non-thermal emission using new INTEGRAL observations obtained close to periastron. Methods: A Chandra observation encompassing the ISGRI error circle was analysed, and all other soft X-ray sources (including the outer shell of Eta Car itself) were discarded as likely counter-parts. New hard X-ray images of Eta Car were studied close to periastron, and compared to previous observations far from periastron. Results: The INTEGRAL component, when represented by a power law (with a photon index of 1.8), ...
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 ...
There is a great demand for the reduction of specific fuel consumption in diesel engines, and also of NO/sub x/ emission in especially those designed for use on land. However, while improving combustion, a problem arises in trying to reduce both simultaneously because the techniques required are contradictory. This series of experiments was done to study the correlation between specific fuel consumption and NO/sub x/ emission. The research was conducted under variations in engine parameters and operating conditions. The variations studied included effects of pressure, temperature and humidity of the charging air, temperature of the cooling water, timing and rate of fuel injection, fuel injection nozzle, EGR and water-emulsified fuel. The results of the tests clarified the characteristics of the specific fuel consumption and NO/sub x/ emission and indicated that the most-effective measures for the reduction of specific fuel ...
Los Alamos National Laboratory is subject to annual emissions-reporting requirements for regulated air contaminants under Title 20 of the New Mexico Administrative Code, Chapter 2, Part 73 (20.2.73 NMAC), Notice of Intent and Emissions Inventory Requirements. The applicability of the requirements is based on the Laboratory's potential to emit 100 tons per year of suspended particulate matter, nitrogen oxides, carbon monoxide, sulfur oxides, or volatile organic compounds. For calendar year 2001, the Technical Area 3 steam plant was the primary source of criteria air pollutants from the Laboratory, while research and development activities were the primary source of volatile organic compounds. Emissions of beryllium and aluminum were reported for activities permitted under 20.2.72 NMAC. Hazardous air pollutant emissions from chemical use for research and development activities were also reported.
This report describes results from emissions testing of a prototype diesel engine, developed by Volvo Truck Corporation of Sweden, which uses pilot injection of diesel fuel for compression ignition of alcohol fuel injection for main combustion. In addition to this dual-fuel engine, emission testing was also conducted on a heavy-duty diesel engine of similar design. Both engines were tested over the 1979 13-mode FTP, or shorter versions of this modal test, and over the 1984 Transient FTP as well as an experimental bus cycle. The dual-fuel engine was characterized with methanol, ethanol and ethanol with 30 percent water (wt %). An oxidation catalyst was also used with methanol and ethanol. Emission characterization included regulated emissions (HC, CO, and NOX) along with total particulate, unburned alcohols, individual hydrocarbons, aldehydes, phenols, and odor. The particulate matter was characterized ...
An experimental investigation was conducted to evaluate the effect of three different oxygenated compounds, diglyme, diethyl maleate and dibutyl maleate, on emissions from a Volkswagen 1.9 litre, turbocharged, direct injection diesel engine. Sampling was performed using a mini-dilution tunnel technique to obtain particulate matter and a Fourier transform infrared (FTIR) spectrometer for gaseous emissions. The particulate samples were analysed using thermal analysis and Soxhlet extraction to determine the fraction of volatile and soluble organic material respectively. All three oxygenated compounds were found to be effective at reducing particulate emissions, with the maleate compounds being more effective overall than the diglyme. Analysis of the relative contributions of changes in the soot and soluble organic fraction (SOF) to the reduction of particulate matter indicated that, for diethyl maleate and diglyme, reductions ...
This report describes the result of work completed during February, 1982 to October 1983. The aim of the work was to develop a low NO(x) emission range top burner. Discussed is the development of a flame insert modification to an existing burner which reduces NO(x) emission by 45 percent and NO2 emission by 25 percent. This relatively simple burner add-on device appears to be an economically viable low NO(x) burner. It was developed in cooperation with a major range manufacturer. The levels of NO(x) (NO2) reduction achieved should significantly reduce the impact of a gas range to indoor quality. The report also discusses the results of a literature search that preceeded the burner development. The search helped to direct the burner development by reviewing the state-of-the-art of low NO(x) burner design and covered factors which affect the indoor impact of range emissions such as air infiltration and ...
Biodiesel is an alternative fuel for internal combustion engines. It can reduce carbon monoxide (CO), hydrocarbon (HC) and particulate matter (PM) emissions, compared with diesel fuel, but there is also an increase in nitrogen oxides (NOx) emission. This study is aimed to compare the effect of applying a biodiesel with either 10% blended methanol or 10% fumigation methanol. The biodiesel used in this study was converted from waste cooking oil. Experiments were performed on a 4-cylinder naturally aspirated direct injection diesel engine operating at a constant speed of 1800 rev/min with five different engine loads. The results indicate a reduction of CO{sub 2}, NOx, and particulate mass emissions and a reduction in mean particle diameter, in both cases, compared with diesel fuel. It is of interest to compare the two modes of fueling with methanol in combination with biodiesel. For the blended mode, there is a slightly higher ...
In the framework of the European Fusion Technology Programme ECN participates in a NET task PSM-8 `Coatings and Surface Effects on Stainless Steel 316L`. High emissivity coatings were developed for enhanced heat transfer from graphite tiles to a Stainless Steel First Wall. Four candidate materials, Cr{sub 2}O{sub 3}, Black Cr, Al{sub 2}O{sub 3}/TiO{sub 2} and TiC were tested as candidate high emissivity coatings. These coatings were manufactured by atmospheric and vacuum plasma spraying technique and the Black Chromium coatings were manufactured by a galvanic coating technique. The tests included total emissivity measurements and Low Cycle Fatigue (LCF) experiments. The total emissivity of two TiC coatings at 525 K appeared to be 0.62 and 0.64. The total emissivity of the TiC and 5 wt% TiO{sub 2}/Al{sub 2}O{sub 3} coating was about 0.7. (orig.)
We present the X-ray properties of a sample of 17 radio sources observed with the Chandra X-ray Observatory as part of a project aimed at studying the X-ray emission from their radio jets. In this paper, we concentrate on the X-ray properties of the unresolved cores. The sample includes 16 quasars (11 core-dominated and 5 lobe-dominated) in the redshift range z=0.30--1.96, and one low-power radio-galaxy at z=0.064. No diffuse X-ray emission is present around the cores of the quasars, except for the nearby low-power galaxy that has diffuse emission on a scale and with a luminosity consistent with other FRIs. No high-amplitude, short-term variability is detected within the relatively short Chandra exposures. However, 1510-089 shows low-amplitude flux changes with a timescale of $\\sim$25 minutes. The X-ray spectra of the quasar cores are generally well described by a single power law model with Galactic absorption. However, ...
The major purpose of the work described in this report was to use diffusion modeling techniques to calculate the impact on ambient air quality of SO2 emissions from the ASARCO copper smelter in Tacoma, Washington for the existing smelter configuration (51-percent constant emissions control) and for 20 alternative smelter configurations with varying degrees of constant emissions control. The accuracy of the modeling techniques was established by the close correspondence obtained between calculated and observed short-term ground-level SO2 concentrations for 20 selected historical cases, when high hourly SO2 concentrations were measured in the area surrounding the smelter, as well as by the close agreement between calculated and observed annual average concentrations for 1972. The results of the model calculations show that the maximum allowable constant SO2 emission rate consistent with maintaining the ...
A sequential port injection, lean-burn, fully electronically-controlled compressed natural gas (CNG)/diesel dual-fuel engine has been developed based on a turbo-charged and inter-cooled direct injection (D.I.) diesel engine. During the optimisation of engine overall performance, the effects of pilot diesel and premixed CNG/air mixture equivalence ratio on emissions (CO, HC, NO{sub x}, soot), knocking, misfire and fuel economy are studied. The rich and lean boundaries of the premixed CNG/air mixture versus engine load are also provided, considering the acceptable values of NO{sub x} and THC emissions, respectively. It is interesting to find that there is a critical amount of pilot diesel for each load and speed point, which proved to be the optimum amount of pilot fuel. Any decrease in the amount of pilot diesel from this optimum amount results in an increase of NO{sub x} emissions, because the premixed CNG/air mixture must ...
We study the origin and properties of 'extra' or 'excess' central light in the surface brightness profiles of cusp or power-law elliptical galaxies. Dissipational mergers give rise to two-component profiles: an outer profile established by violent relaxation acting on stars already present in the progenitor galaxies prior to the final stages of the merger, and an inner stellar population comprising the extra light, formed in a compact central starburst. By combining a large set of hydrodynamical simulations with data that span a broad range of profiles at various masses, we show that observed cusp ellipticals appear consistent with the predicted 'extra light' structure, and we use our simulations to motivate a two-component description of the observations that allows us to examine how the properties and mass of this component scale with, e.g., the mass, gas content, and other properties of the galaxies. We show how to ...
Formation of particles from heavy duty diesel and CNG vehicles was studied in laboratory conditions. PM, nano and soot mode particle emissions formed from buses of Euro 2-5 -emission levels were studied in relation to age and type approval characteristics of the vehicle. Characteristic particle emission factors from city driving were obtained by driving the buses on VTT's heavy duty chassis dynamometer applying the transient Braunschweig city cycle. The vehicles were a representative set of Euro 2 to 3 emission categories, supplemented with Euro 4-5 (EEV) -targeted CRT, CNG and DPF cars. Particle number emissions from Euro 4 to 5 buses were 1/100-1/1000 and mass emissions 1/10-1/100 of those of the current fleet. Particle emission from natural gas buses and after an advanced CRT trap contained almost entirely liquid < 60 nm ...
This report documents radionuclide air emissions from the Hanford Site in I998 and the resulting effective dose equivalent to the maximally exposed individual (MEI) member of the public. The report has been prepared in accordance with the Code of Federal Regulations, Title 40, Protection of the Environment, Part 61, National Emission Standards for Hazardous Air Pollutants (40 CFR SI), Subpart H, ''National Emission Standards for Emissions of Radionuclides Other than Radon from Department of Energy Facilities,'' and with the Washington Administrative Code Chapter 246-247, Radiation Protection--Air Emissions. The federal regulations in 40 CFR 61, Subpart H; require the measurement and reporting of radionuclides emitted from Department of Energy facilities and the resulting offsite dose from those emissions. A standard of 10 ...
Randomly oriented ZnO microsheets were successfully self-assembled on TiO2 nanoparticle (TN) film to act as the scattering layer via a cathodic electrodeposition process. The light scattering properties of ZnO microsheets were studied by UV-Vis spectrometer in the 400?800 nm wavelength range. It was found that ZnO microsheets exhibited excellent ability to scatter the incident light for ZnO microsheet-TiO2 nanoparticle (ZT) composite films. The results showed that dye-sensitized solar cells (DSSCs) fabricated with ZT composite films showed higher short-circuit density (J sc) and conversion efficiency than TN-based DSSCs, due to the light scattering properties of ZnO microsheets.
For a solar cell, in order to minimize the loss of incident light, transparent glass or plastic material is used at the incident part. When a solar cell is watched from the light incident part, a silicon base material is directly observed with either block or brown color only. This invention enables a solar cell to give brighter color on the incident surface by placing a reflective film which reflects only the light of specific wavelength, without reducing the efficiency of the solar cell. This reflective film consists of multi-layered dielectric with 12 layers and alternative combination of highly refractive and less refractive substances. Highly refractive layer is Y/sub 2/O/sub 3/ with refractive index 1.74 and the less refractive layer is SiO/sub 2/ with refractive index 1.45. (5 figs)
A 100-bit slitlike aperture array spatial light modulator has been developed using 8.8/65/35 PLZT for a high-bit-density 1-D hologram memory. The most desirable characteristics, such as distortion-free diffraction-limited Fourier transform patterns and good uniformity of displayed bit patterns over 100 bits, have been realized. The lowest SNR was 86, and rise time and fall time have been 30 microsec and 8 microsec, respectively, at 190-V halfwave voltage. One-dimensional holographic storage experiments have been successfully performed using this PLZT spatial light modulator. PMID:20216813
While radiation-pressure cooling is well known, the Brillouin scattering of light from sound is considered an acousto-optical amplification-only process. It was suggested that cooling could be possible in multi-resonance Brillouin systems when phonons experience lower damping than light. However, this regime was not accessible in traditional Brillouin systems since backscattering enforces high acoustical frequencies associated with high mechanical damping. Recently, forward Brillouin scattering in microcavities has allowed access to low-frequency acoustical modes where mechanical dissipation is lower than optical dissipation, in accordance with the requirements for cooling. Here we experimentally demonstrate cooling via such a forward Brillouin process in a microresonator. We show two regimes of operation for the Brillouin process: acoustical amplification as is traditional, but also for the first time, a Brillouin cooling regime. Cooling is ...
Details of the interaction of photons with tissue phantoms are elucidated using Monte Carlo simulations. In particular, photon sampling volumes and photon pathlengths are determined for a variety of scattering and absorption parameters. The Monte Carlo simulations are specifically designed to model light delivery and collection geometries relevant to clinical applications of optical biopsy techniques. The Monte Carlo simulations assume that light is delivered and collected by two, nearly-adjacent optical fibers and take into account the numerical aperture of the fibers as well as reflectance and refraction at interfaces between different media. To determine the validity of the Monte Carlo simulations for modeling the interactions between the photons and the tissue phantom in these geometries, the simulations were compared to measurements of aqueous suspensions of polystyrene microspheres in the wavelength range 450-750 nm.
The light gain due to S/sub 2/ molecules in a supersonically cooled gas mixture is calculated. The S/sub 2/ molecules formed due to the recombination of the sulfur atoms, and the combustion gas mixture was preheated in a precombustion chamber. Optimal gas flow and nozzle parameters are found which correspond to the highest possible light gain using Cs/sub 2/-Ar and S/sub 2/-Ar gas mixtures. The steady state gas flow in the nozzle was calculated, taking into account the chemical reactions in the one-dimensional approximation. It is shown that the maximum gain values vary in the 0.0001-0.002 range for gas pressures in the precombustion chamber in the range 10-100 atm. The optimal initial relative concentration of Cs/sub 2/ molecules and S/sub 2/ molecules are given. 32 references.
Efficient, low-temperature conversion of infrared light into visible light (red, orange, green) is reported at single heterojunctions and undoped quantum wells of GaAs and ordered Al_xGa_1_-_xInP_2; an increase in photon energy of 700 meV is obtained. The signal originates from the high-band-gap layers and disappears only if the excitation energy is tuned below the GaAs band gap. The intensity of the up-converted photoluminescence (PL) is found to decrease significantly slower with increasing temperature than that of the regular PL and it remains observable up to 200 K. Interface-induced cold Auger processes along with the presence of trapped states for both electrons and holes in these ordered alloys account for this nonlinear mechanism. A colinear double-beam experiment confirms this. copyright 1996 The American Physical Society.
An effective method of enhancing charge injection and electroluminescence efficiency of polymer-based light emitting diode is introduced. Spin-coated films of poly (N-vinylcarbazole) blended with electron-transport material (Bu-PBD), laser dye (Coumarin6), and the typical supporting electrolyte (tetraethylammonium perchlorate; TEAP) were examined and it was found that the injection current and luminance of the light emitting diode doped with TEAP were enhanced dramatically after heat-treatment at 80 deg. C and appropriate biasing in an external electric field of 1.5x10"8 V/m at this temperature. The thermally stimulated current (TSC) was also measured to investigate the relaxation process of ionic space charges in the films. The relaxation times of ionic polarization were found to be related to the cation size of the electrolyte. And the relaxation time becomes long enough by the use of TEAP doping.
AbstractBackground In recent years nano-metaloxides which easily penetrate into the cells with special interest due to their higher chemical reactivity as compared to that of similar materials in the bulk form. Of particular interest are nano-TiO2 and ZnO, which have been widely used for their bactericidal and anticancerous properties. Purpose The aim of the present study was to examine the bactericidal properties of nano-TiO2 and ZnO combined with visible light on S. aureus and S. epidermitis, known for their high prevalence in infected wounds. Study Using the technique of electron-spin resonance (ESR) coupled with spin trapping, we examined the ability of TiO2 and ZnO nanoparticle suspensions in water to produce reactive oxygen species (ROS) with and without visible light irradiation. Th...
Purpose To investigate the influence of timolol maleate 0.5% gel-forming solution and brinzolamide 1% ophthalmic suspension on contrast sensitivity, ocular higher-order aberration (HOA), and corneal surface light scattering. Design Prospective, comparative study. Participants Forty normal volunteers were enrolled in this study. Methods We evaluated contrast sensitivity, ocular HOA, and corneal light scattering before and 2, 5, 10, and 15 minutes after instillation of antiglaucoma eyedrops. Contrast sensitivity function was assessed with the CSV-1000RN chart (Vector Vision Co., Greenville, OH). Higher-order aberration was measured for a 4-mm pupil using the Hartmann-Shack aberrometer (KR-9000PW; Topcon, Tokyo, Japan). Corneal surface light scattering was quantitatively evaluated by using th...
A 253.7-nm ultraviolet light with an intensity of 1,100 microW/cm2 was tested for its germicidal activity against contact lenses and storage solutions contaminated with various corneal pathogens. The exposure time necessary to reduce a concentration of organisms from 10(6)/ml to less than 10/ml was 30 seconds for Staphylococcus aureus, 60 seconds for Pseudomonas aeruginosa, and 84 seconds for Candida albicans. The time necessary to sterilize a suspension of 10(4)/ml Acanthamoeba polyphaga was less than three minutes with this technique. Four brands of soft contact lenses were exposed to ultraviolet light for over eight hours without changing their appearance, comfort, or refraction.
The Arabidopsis ref2 mutant was identified in a screen for plants having altered fluorescence under UV light. Characterization of the ref2 mutants showed that they...Full Text Available
Arguments in favour of the possibility of the existence and the non-existence of tachyons are put forward. Some of the theoretical and experimental attempts which have either supported the view that tachyons exist or not are mentioned. In the light of evidence, available as of now, it is surmised that they may not exist and if they do, they may be neutral in charge. (K.B.).
The status of the electroweak Standard Model is reviewed in the light of recent precision data and new theoretical results which have contributed to improve the predictions for precision observables, together with the remaining inherent theoretical uncertainties. Consequences for possible new physics are also discussed.
Inhibition of photosynthesis by ultraviolet-A radiation (UV-A, 315-380 nanometers) was examined in three marine angiosperms: Halophila engelmannii Aschers, Halodule wrightii...Full Text Available
It is the purpose of this paper to prove that a preferred space direction is coupled with each tachyon and, consequently, scalar tachyons, are impossible in principle. Even the notion of a scalar faster-than-light particle cannot be defined in a relativistically invariant way.
Diel variations in rates of C export, sucrose-phosphate synthase (SPS) and sucrose synthase (SS) activity, and C reserves were investigated in Zostera marina L. (eelgrass) to elucidate the environmental...Full Text Available
Arbuscular mycorrhizal fungi (AMF) are obligate biotrophs, known to play an important role in ecological processes. Conventional light microscopy is the most common method used to detect their presence...Full Text Available