The potential for achieving high conversion ratios in HTGRs is demonstrated analytically. The design modifications required to achieve a variety of different conversion ratios, including cases exceeding 0.90 for U-235 fueled HTGRs are discussed. The impor...

Spectral control is an important consideration in achieving high conversion efficiency with thermophotovoltaic (TPV) energy conversion systems. TPV modules using front surface filters as the primary spectral control device have demonstrated conversion eff...

Highly aromatic tricyanate ester resins exhibit glass transition temperatures well in excess of 350 degrees Celsius when thermally cured to full conversion. In many cases, though, complete conversion is difficult to achieve in practice due to the highly r...

The use of dry extruders in cooking grains for fermentation has been investigated. It is possible to consistently achieve better conversion than with standard batch methods. Best performance is achieved at high temperature and low moisture content. The affect of substrate concentration, dextrose equivalence, and ...

This text contains information for the conversion of coal to alternative fuels and the health and environmental impacts of such conversion. Summarizes the many technological approaches to coal conversion and the resultant products and by-products of concern. Also discusses research and data that can make possible the design and ...

... One method to achieve maximum efficiency is to operate the power supply, energy conversion system, and related components at relatively high ...

8 MODLES FILED(BYPMSSED)_AS. A FUNCTION OF THENUMBEROF ...... lel fashion. Alternately, the conversion can be achieved by a partial and ...

In contrast to the prior art, by a discrete combination of the various features and conditions in accordance with this invention, superior results are obtained in a continous operation. It is an object of the present invention to achieve high and increase...

The HTGR offers significant improvements in the utilization of uranium and thorium by increases in the conversion ratio of fissile nuclides. The possible tradeoffs in core design features which result in higher conversion ratios are discussed. The cost effects of fuel cycle tradeoffs affecting resource utilization are presented in graphical form. ...

... structure and fabricated into 1cm long bars with 1mm cavity length. As a result, we were able to achieve a record high power conversion efficiency ...

We present a geometrical representation of the process of sum frequency generation in the undepleted pump approximation, in analogy with the known optical Bloch equations. We use this analogy to propose a technique for achieving both high efficiency and large bandwidth in sum frequency conversion using the adiabatic inversion scheme. ...

The use of dry extrusion cookers for gelatinizing grain starch has been investigated. It is possible to consistently achieve better conversion with extrusion than with standard batch methods. Best performance was achieved at high temperatures and low mois...

A new concept is proposed for a high conversion light water reactor (HCLWR) that achieves both high conversion and high burnup while maintaining a negative void reactivity coefficient. This HCLWR has a flat pancake core with thick axial blankets. By using the flat core, a ...

The frequency quadrupoling of the high power Nd:YAG laser in a deuterated cesium dihydrogen arsenate-ammonium dihydrogen phosphate (CD*A-ADP) cascade frequency converter is reported. An overall power conversion efficiency of 15% was achieved for the experimental conditions described. The nonlinear absorption affecting the ...

Theory of thermoelectric energy conversion at high temperatures and status of research on conversion

The objective of this project was to develop an economical conversion technique to convert a conventional integral quench heat treating furnace to a fluidized bed integral quench furnace to achieve improved energy efficiency in heat treating operations. A used conventional integral quench furnace was converted to a fluidized bed integral quench furnace by ...

This report describes the concentrating solar power (CSP) systems using solar absorbers to convert concentrated sunlight to thermal electric power. It is possible to achieve solar absorber surfaces for efficient photothermal conversion having high solar a...

The components of synthesis gas can be converted into ethanol by the bacterium Clostridium ljunfdahlii, Strain PETC. This microorganism achieves complete conversion of synthesis gas and gives stoichiometric yields of ethanol with high energy efficiency. T...

The development of GaAsP/GaP devices was made for stacking on silicon bottom cells to achieve high conversion efficiencies. The estimated efficiency of the completed devices was 21% AMO under concentrated light. A four terminal sack was incorporated to al...

Carbon dioxide is converted to urethanes (carbamic acid derivatives) through reaction with amine and alcohol catalyzed by tin complexes; th addition of acetals as a dehydrating agent under high CO2 pressure is the key to achieve high yields. PMID:12240129

Significant progress has been achieved recently in the growth of Yttrium Calcium Oxyborate (YCOB) crystals. Boules have been grown capable of producing large aperture nonlinear crystal plates suitable for high average power frequency conversion or optical...

An optomechanical interface that converts quantum states between optical fields with distinct wavelengths is proposed. A mechanical mode couples to two optical modes via radiation pressure and mediates the quantum state mapping between the two optical modes. A sequence of optomechanical ?/2 pulses enables state-swapping between optical and mechanical states, as well as the cooling of the ...

The use of a low finesse enhancement cavity resonant with a low average power (<1 W) and a high repetition rate (78 MHz) pump source is shown to achieve 55% conversion efficiency into signal and idler from the coupled pump in an optical parametric process, whereas an equivalent amount of pump power in a single-pass configuration ...

An innovative concept for steam methane reforming (SMR), based on reformer and membrane modules (RMMs), has been developed and tested to investigate its performance, in terms of feed conversion, on an industrial scale. A major benefit of the proposed RMM configuration is a shift of the chemical equilibrium of SMR reactions, achieved by removing the ...

Structured conversation diagrams, or conversation specifications, allow agents to have predictable interactions and achieve predefined information-based goals, but they lack the flexibility needed to function robustly in an unpredictable environment. We propose a mechanism that combines a typical conversation ...

stress in the structure. 4. The temperature variation throughout the first wall and blanket is low, resulting in low structural distortion and thermal stresses. 5. The lithium flow rate is approximately of the blanket is cooled by a conventional self-cooled liquid lithium blanket with an exit temperature of also

School reformers hope that converting comprehensive high schools into collections of small schools will produce results similar to those realized in freestanding small schools. This comparative case study revisits two "conversions" as they complete the grant funding that supported the reform, in order to explore the extent to which changes ...

A thermal-hydraulic characteristics of double flat core high conversion light water reactor (HCLWR) is described. The concept of flat core proposed by Ishiguro et al. is to achieve negative void reactivity coefficient in tight lattice core, and at the sam...

cw power conversion efficiencies of 57% have been obtained on uncoated diode lasers emitting nearly 300 mW per facet. This performance is achieved by using a low-resistance graded index separate confinement single quantum well AlGaAs/GaAs structure with high (84%) differential quantum efficiency and low threshold current.

Second-to-fourth harmonic conversion efficiencies of 80% in a Nd:YLF oscillator/glass amplifier system have been achieved. At high fourth harmonic intensities, beam break up and anomalous pulse shape effects are observed. 2 refs., 2 figs.

Photon conversion efficiencies of 60% at 2.92 {mu}m and 25% at 4.5 {mu}m of a high-power injection-seeded Ti:sapphire laser have been achieved by difference frequency mixing with the new crystal KTiOAsO{sub 4}.

The synthesis of highly functionalised N-heterocycles has been achieved by the visible light mediated photoredox conversion of tertiary amines to azomethine ylides and their further reaction with maleimide derivatives as dipolarophiles. PMID:21792444

Nuclear-based magnetohydrodynamic (MHD) energy conversion has been pursued in various forms since the 1950's. The majority of this work was motivated by the compatibility of MHD generators with the high temperature achievable with a nuclear reactor and th...

The high efficiency of energy generation inferred from radio observations of quasars and X-ray observations of Seyfert active galactic nuclei (AGNs) is apparently achieved only by the gravitational conversion of the rest mass energy of accreting matter on...

The efficiency of thermophotovoltaic (TPV) energy conversion is dependent on efficient spectral control. An edge pass filter (short pass) in series with a highly doped, epitaxially grown layer has achieved the highest performance of TPV spectral control. PMID:16539234

The work has resulted in the identification of a new strategy for predicting perovskite solid electrolytes with the potential for achieving high ionic conductivities at intermediate temperatures. This approach is based in part upon identification of a cle...

An argon-ion laser achieves low output power by using a plasma guide and mirror configuration which restricts lasing action to a portion of the resonator cavity at relatively high conversion efficiency.

Achieved world record conversion efficiency (>19%) for indium phos- phide (InP) cells; Confirmed radiation hardness by actual flight experiment Photovoltaic ...

This study addresses the problem of finding an energy conversion method to take advantage of the high maximum cycle temperatures achieved with solar central receivers. Most current practice is to use steam-based heat engines with solar receivers but these...

Frequency tunable VUV radiation has been generated using excimer lasers and very narrow bandwidth dye lasers by twophoton resonant difference frequency mixing in xenon. Conversion efficiencies of >0.1 percent have been achieved.

The original plan for the project involved design modifications to an existing system to enhance its performance and increase the limit of power that was achieved by the original design and to apply the higher performance product to the full sized engine ...

A conceptual definition and performance evaluation of a 100 megawatt (MW) hybrid photovoltaic/thermal electric power plant has been carried out. The concept utilizes the ability of gallium arsenide photovoltaic cells to achieve high conversion efficiency ...

The efficiency of thermophotovoltaic (TPV) energy conversion is dependent on efficient spectral control. An edge pass filter (short pass) in series with a highly doped, epitaxially grown layer has achieved the highest performance of TPV spectral control. Front surface, tandem filters have achieved the highest ...

In contrast to the prior art, by a discrete combination of the various features and conditions in accordance with this invention, superior results are obtained in a continous operation. It is an object of the present invention to achieve high and increased conversion of coal to liquid product. Another objective is to ...

Laser diodes and bars with high efficiency, power, and reliability are critical for a wide variety of applications including direct material processing and pumping high power and efficient fiber lasers and solid state lasers. We present progress towards the 80% power conversion efficiency goal of the DARPA Super ...

A titanium doped sapphire is pumped with up to 900 mJ of blue-green energy from a dye laser. An 8 percent energy conversion to the near IR is demonstrated. The experimental input/output data agree well with calculations based on the measured characteristics of crystal and pump beam. Analysis of the conversion efficiency reveals the potential to ...

Reviews research on proficiency levels attained by foreign language students, and describes an advanced Russian conversation course, which is geared toward students who have achieved intermediate-mid or intermediate-high oral proficiency and who are striving towards advanced level speech according to the American Council on the ...

Measurements have been made of the spontaneous Raman scattering linewidth, the Stokes shift of the scattered radiation frequency, and the gain and conversion efficiency of the radiation from single-pulse neodymium lasers under SRS in a KGd(WO4)2 crystal. The possibility of achieving high SRS efficiency and of tuning the converted ...

A conversion ratio of near 1.0 can be achieved in a pebble-bed reactor using the OTTO (once through then out) loading scheme, having an economic burn-up of the fuel, an economic power density and a moderation ratio, which is considered realistically for t...

We describe a magnetohydrodynamic (MHD) electrical power generator equipped with a convexly divergent channel, as determined through shock-tunnel-based experiments. The quality of MHD power-generating plasma and the energy conversion efficiency in the convexly divergent channel are compared with those from previous linearly divergent channel. The divergence enhancement in the ...

The authors examine two methods to upgrade the detection efficiency of thermal neutron semiconductor detectors. The first of these involves increasing the number of semiconductor detection and neutron conversion layers in the sandwich while the second is based on the use of semiconductor crystals with an extended surface. They incorporate both methods into a design program for ...

The gas-phase homogeneous partial oxidation of methane with oxygen was studied over a range of operating conditions in a high-pressure tubular reactor. The experimental data indicated that methanol selectivities of 70 - 80% could be achieved at methane conversions of 8 - 10% by operating at suitable reaction conditions. The higher ...

presents some recent achievements in modeling and optimization of energy hubs: � Inclusion of storage of operation (optimal energy conversion and storage) and plan- ning (optimal hub layout). An example energy flows through energy hubs is presented. Models for energy conversion and storage are integrated

Two years have passed since the South African Department of Minerals and Energy authorised the conversion from High Enriched Uranium (HEU) to Low Enriched Uranium (LEU) of the South African Research Reactor (SAFARI-1) and the associated fuel manufacturing at Pelindaba. The scheduling, as originally proposed, allowed approximately three years for the full ...

This report describes progress during the first year of a three-year project. The objective of the research is to examine new design approaches for achieving very high conversion efficiencies. The program is divided into two areas. The first centers on exploring new thin-film approaches specifically designed for III-V semiconductors. ...

farms. Four possible outcomes necessary to achieve conversion of 25 percent of the area to organic farming were analyzed. ...

Mode conversion of p-polarized electromagnetic waves into longitudinal plasma oscillations at resonance points in cold, unmagnetized, and stratified plasmas, where a small periodic density modulation is superimposed on a linear electron density profile, is theoretically studied. The mode conversion coefficient and the magnetic field distribution are ...

The conversion efficiency and noise figure (NF) of the silicon-on-insulator (SOI) waveguide-based wavelength converter are investigated with the coupled equations. The effects of the pump power, the nonlinear absorption and the waveguide length on the conversion efficiency and noise figure are discussed. The conversion efficiency ...

We report five children and adolescents who displayed a conversion reaction in response to stresses induced by athletic competition. Failure to make proper diagnosis led to additional physician referral, needless testing, rehabilitation, or orthotic management. Patients are characterized as high achievers who are frequently younger ...

The objectives of the study are to: assess the potential of wind energy conversion systems (WECS) on a national scale; identify those combinations of size, application, and requirements which have the best chances of being implemented; establish the requirements and goals for wind energy conversion systems in terms of functions, performance, cost, and ...

The VisABC process effectively combines low-cost visbreaking and selective asphaltenic bottom cracking (ABC) hydroprocessing to convert heavy feedstock to distillate products. Visbreaking thermally converts residue to a lighter fraction and condenses part of the nonasphaltenes to aromatic materials including asphaltenes. The subsequent ABC reaction cracks asphaltene molecules and produces maltenes ...

Nonrelativistic equations of electron motion in varying magnetic and electric fields in a thin-sphere segment are presented. An analysis is given of the geometry-optimization of a collector with the aim of increasing the efficiency of inverse conversion in microwave converters (such as those planned for systems involving microwave power transmission from satellite solar power ...

In order to achieve the desired efficiency in the MHD cycle, one of two procedures must be employed. The first is to inject pure oxygen during combustion in order to achieve higher combustion temperatures which will yield better conversion efficiencies. T...

The precipitation polymerization of styrene-trihydroxymethyl propane triacrylate has been carried out using ethanol and an ethanol/water mixture as the solvent. Uniform microspheres with high monomer conversion are achieved within 4 h, a much shorter polymerization time than that reported for the precipitation polymerization of divinyl ...

This book describes materials of construction, and materials problems for equipment used in advanced coal conversion systems. The need for cost effective industrial operation is always a prime concern, particularly in this age of energy consciousness. Industry is continually seeking improved materials for more efficient systems. The information presented here is intended to be ...

The high efficiency reported recently by NREL for CIGS solar cells demonstrates the potential of band gap grading in producing high efficiency thin film solar cells. In order to reap the full benefits of this design strategy, a clear understanding of the fundamental device physics of these structures is needed. The purpose of this paper is to examine the ...

This paper assesses the technological and economic feasibility of achieving net electric power from a near-term fusion device by using high efficiency energy conversion technology. A variety of energy conversion/reactor blanket schemes have been considered and the best one, an argon topping cycle, steam bottoming ...

The objective is to produce a Synthetic crude from coal at a cost lower than $30.00 per barrel (Task A). A second objective is to produce a fuel which is low in aromatics, yet of sufficiently high octane number for use in the gasoline-burning transportation vehicles of today. To meet this second objective, research was proposed, and funding awarded, for ...

The objective of the current research in coal liquefaction is to produce a synthetic crude from coal at a cost lower than $30.00 per barrel (Task A). A second objective is to produce a fuel which is low in aromatics, yet of sufficiently high octane number for use in the gasoline-burning transportation vehicles of today. To meet this second objective, research was proposed for ...

Highly efficient generation of UV radiation at 355 nm has been achieved in a LiB(3)O(5) crystal through the frequency mixing of the fundamental and second-harmonic radiation of a Nd:YAG laser. An energy conversion efficiency of 60% has been obtained under the experimental conditions described here. Thus the usefulness of LiB(3)O(5) for ...

CANMET is a new residuum hydrocracking process, capable of achieving high conversion on difficult feedstocks. A description is given of the process and detailed performance data are presented for the upgrading of Laguna vacuum bottoms. The economic performance of the technology is evaluated in a case study where CANMET unit for ...

The first successful high power heating of a high dielectric constant spherical tokamak plasma by an electron Bernstein wave (EBW) is reported. An EBW was excited by mode conversion (MC) of an mode cyclotron wave injected from the low magnetic field side of the TST-2 spherical tokamak. Evidence of electron heating was observed as ...

Light hydrocarbon gases could be reacted with low cost alkaline earth metal oxide (CaO, MgO) in high-temperature plasma reactor to achieve very high ([le]100%) gas conversion to H[sub 2], CO, and the corresponding metal carbides. These carbides could be stored, transported, and hydrolyzed to acetylene or methyl ...

This report describes progress made to develop a high bandgap photovoltaic materials for direct conversion to electricity of excimer radiation produced by fission energy pumped laser. This report summarizes the major achievements in sections. The first section covers n-type diamond. The second section covers forced diffusion. The third ...

A hybrid process employing both biological and thermochemical conversion of biomass to methane was studied. A unique high-moisture catalytic gasifier concept was used to gasify the effluent from an anaerobic digester. An ASPEN-PLUS/sup tm/ simulation of the process concept was based upon experimental data obtained from individual process components. An ...

The conversion efficiency and service life of the laser elements based on a polymer-filled microporous glass (PFMPG) composite doped with organic dyes are studied. It is shown that both the conversion efficiency and the service life of the laser elements achieve the values obtained for the same dyes in bulk polymer elements. Good ...

The first high-yield, direct catalytic conversion of methane by a transition-metal compound in homogeneous solution has been achieved at Pennsylvania State University by chemistry professor Ayusman Sen and his coworkers. There are practical as well as ''scientific'' reasons for pursuing the ...

Fibrous rare earth composite emitters were developed for the application of thermophotovoltaic (TPV) energy conversion to increase the energy conversion efficiency of the system. In this paper, the authors demonstrated that fibrous composite emitters, with higher selective efficiency and good mechanical properties, were fabricated using a unique material ...

Fibrous rare earth composite emitters were developed for the application of thermophotovoltaic (TPV) energy conversion to increase the energy conversion efficiency of the system. In this paper, the authors demonstrated that fibrous composite emitters, with higher selective efficiency and good mechanical properties, were fabricated using a unique material ...

We characterize silicon waveguide based wavelength converters using a commercial semiconductor optical amplifier (SOA) based wavelength converter as a benchmark. Conversion efficiency as high as -5.5 dB can be achieved using a 2.5 cm long sub-micron silicon-on-insulator rib waveguide. Comparison with the SOA reveals that silicon offers ...

Using published results as a data base, this paper illustrates how a deterministic model can be developed and utilized for the optimum allocation of biomass feedstocks. An example is presented for production and utilization of methanol from biomass because of methanol's versatile applicability to the electricity, transportation, and chemical sectors. Three feedstocks were selected for ...

The Institute of Gas Technology (IGT) U-GAS process for medium-Btu gas offers a means to achieve a clean fuel from coal with minimal particulate and sulfur dioxide flue-gas emissions. The U-GAS process combines a single-stage fluidized-bed gasifier with an ash agglomerating mechanism that achieves high carbon ...

The retrofit or conversion of automotive engines to operate on liquid petroleum gas (LPG) or propane fuel is one of many potentially cost-effective strategies for reducing a local government's annual fleet operating and maintenance costs. The cost effectiveness of an LPG conversion decision is highly dependent on the initial ...

The development of appropriate reactors is crucial for the production of biodiesel. In this study, a packed-bed reactor system using lipase-Fe(3)O(4) nanoparticle biocomposite catalyst was successfully developed for biodiesel production based on soybean oil methanolysis. Emulsification before methanolysis improved the reaction rate. The lipase-nanoparticle biocomposite showed ...

There is disclosed a polymer blend of a highly conductive polymer and a solid polymer electrolyte that is designed to achieve better charge transfer across the conductive film/polymer electrolyte interface of the electrochemical photovoltaic cell. The highly conductive polymer is preferably polypyrrole or poly-N-p-nitrophenylpyrrole ...

A polymer blend is disclosed of a highly conductive polymer and a solid polymer electrolyte that is designed to achieve better charge transfer across the conductive film/polymer electrolyte interface of the electrochemical photovoltaic cell. The highly conductive polymer is preferably polypyrrole or poly-N-p-nitrophenylpyrrole and the ...

There is disclosed a polymer blend of a highly conductive polymer and a solid polymer electrolyte that is designed to achieve better charge transfer across the conductive film/polymer electrolyte interface of the electrochemical photovoltaic cell. The highly conductive polymer is preferably polypyrrole or poly-N-p-nitrophenylpyrrole ...

There is disclosed a polymer blend of a highly conductive polymer and a solid polymer electrolyte that is designed to achieve better charge transfer across the conductive film/polymer electrolyte interface of the electrochemical photovoltaic cell. The highly conductive polymer is preferably polypyrrole or poly-N-p-nitrophenylpyrrole ...

There is disclosed a polymer blend of a highly conductive polymer and a solid polymer electrolyte that is designed to achieve better charge transfer across the conductive film/polymer electrolyte interface of the electrochemical photovoltaic cell. The highly conductive polymer is preferably polypyrrole or poly-N-p-nitrophenylpyrrole ...

Power levels of 17 kW in 0.7 microsecond pulses have been obtained from the 2.14 mm transition of NH3 when optically pumped by a 65 J CO2 TEA laser. Photon conversion efficiencies of 11 percent have been achieved. This is the first high-power laser line observed to work in the 140 GHz atmospheric window. 12 references.

The synthesis of micro/mesoporous aluminosilicate with a hexagonal arrangement of pores has been achieved by cationic surfactant-templating in a tetramethylammonium-containing solution precursor of colloidal faujasite; this material is zeolite nanocrystal-free and exhibits high catalytic activity in m-xylene conversion. PMID:12611010

The question of how the positive ions of a plasma get their large observed energies in the short duration of the discharge is discussed. A mechanism involving oscillation is considered. It is concluded that the achievement of high yields and high-energy conversion efficiencies depends on getting most of ...

Significant improvements in open-circuit voltage and conversion efficiency, even on relatively high bulk resistivity silicon, were achieved by using a screen-printed aluminum paste back surface field. A 4 sq cm 50 micron m thick cell was fabricated from t...

Catalytic synthesis of isobutyraldehyde from methanol and n-propyl alcohol was achieved by using titanium oxide-supported vanadium oxide catalysts in one step. At high conversion (> 90%), isobutyraldehyde was formed in high yield (> 60%) with minor amounts of propionaldehyde, propane, and isobutane. The ...

Corn stover was pretreated for compositional fractionation and structural modification for maximum conversion of carbohydrate to soluble sugars. The process scheme consisted of three steps: (1) mild prehydrolysis if dilute sulfuric acid, (2) delignification with various organosolv solvents, and (3) enzymatic hydrolysis in an agitated bead reactor. Prehydrolysis of corn stover ...

We experimentally demonstrate observation of highly pure four-photon GHZ entanglement produced by parametric down-conversion and a projective measurement. At the same time this also demonstrates teleportation of entanglement with very high purity. Not only does the achieved high visibility ...

The conversion of sunlight into electricity has been dominated by photovoltaic and solar thermal power generation. Photovoltaic cells are deployed widely, mostly as flat panels, whereas solar thermal electricity generation relying on optical concentrators and mechanical heat engines is only seen in large-scale power plants. Here we demonstrate a promising flat-panel solar ...

The conversion of sunlight into electricity has been dominated by photovoltaic and solar thermal power generation. Photovoltaic cells are deployed widely, mostly as flat panels, whereas solar thermal electricity generation relying on optical concentrators and mechanical heat engines is only seen in large-scale power plants. Here we demonstrate a promising flat-panel solar ...

High ash containing residues from the liquefaction of Kentucky 9/14 coal using the SRC-I process were successfully gasified in a pilot plant Texaco Coal Gasifier at 24 atmospheres pressure. Four sets of runs were completed using filter cake, high ash SRC and Kentucky coal in various mixtures. The first set consisted of three short exploratory runs charging ...

Frequency conversion is considered as a key functionality for wavelength division multiplexing systems, which converts an incoming optical carrier of one frequency to an outgoing optical carrier of another frequency while preserving the quality of carried data. The all-optical approach is promising for such a purpose because not only the system complexity and power consumption ...

From the earliest days of power reactor development, direct energy conversion was an obvious choice to produce high efficiency electric power generation. Directly capturing the energy of the fission fragments produced during nuclear fission avoids the intermediate conversion to thermal energy and the efficiency limitations of classical ...

The photoelectrical responsibility of single photo-electronic devices makes it difficult to achieve high efficiency of photoelectric conversion in the full solar spectrum range. The key to overcome the physical limits is to develop the system consisting of a set of solar cells in which the photo-electronic ...

Hydrogen gas provides exceptional value as an energy carrier and industrial feedstock, but currently is produced entirely by reforming fossil fuels. Biological hydrogen production (BioH(2)), which offers the possibility of being renewable and carbon neutral, can be achieved by photosynthesis, fermentation, and microbial electrolysis cells. This review introduces the ...

A new cascaded microwave photonic filter that can realize a high Q value is presented. It consists of two infinite impulse response filters based on two active loops. Owing to wavelength conversion employing cross-gain modulation of the amplified spontaneous emission spectrum of the semiconductor optical amplifier in one loop, the interference between the ...

State-of-the-art materials like Bi[sub 2]Te[sub 3], PbTe and SiGe alloys have been successfully used in thermoelectric energy conversion systems. Although significant improvements of their thermoelectric properties were recently achieved, their thermoelectric efficiency remains relatively low and new classes of materials must be developed to ...

We report high-power laser operation that was achieved with a-cut and c-cut Yb:LuVO4 crystals. Up to 8.3 W of ?-polarized output power was generated from an a-cut, 2 mm uncoated crystal with an optical conversion efficiency of 59%. The highest slope efficiency was 80%. Laser oscillation obtained with c-cut crystal was also linearly ...

We demonstrate an approach to measure temporal correlations of photons in the near infrared range using frequency up-conversion. In this approach, the near infrared signal photons are converted into the visible range, in which highly efficient silicon avalanche photodiodes are used to perform the temporal correlation measurements. A coherent light source ...

Average second-harmonic power at 5.3 ..mu..m exceeding 0.75 W with a 17% power conversion efficiency has been obtained by pumping a CdGeAs/sub 2/ crystal, cooled to near 77 K, with a Q-switched CO/sub 2/ laser. Average and peak conversion efficiencies of 21 and 30%, respectively, were achieved at a pulse rate of 1.5 kHz. In cw ...

We demonstrate highly efficient generation of coherent 420 nm light via up-conversion of near-infrared lasers in a hot rubidium vapor cell. By optimizing pump polarizations and frequencies we achieve a single-pass conversion efficiency of 260% per Watt, significantly higher than in previous experiments. A full ...

Optimum production and utilization of spin-polarized deuterium as a fusion fuel requires long nuclear spin-lattice relaxation times at temperatures near 4K. This can be achieved with very high purity ortho-D2. Experimental methods and results of total-adsorption catalysis of D2 para-ortho conversion in the 4 to 15K temperature region ...

Optimum production and utilization of spin-polarized deuterium as a fusion fuel requires long nuclear spin-lattice relaxation times at temperatures near 4K. This can be achieved with very high purity ortho-D/sub 2/. We report new experimental methods and results of total-adsorption catalysis of D/sub 2/ para-ortho conversion in the 4 ...

This report describes to examine new solar cell desip approaches for achieving very high conversion efficiencies. The program consists of two elements. The first centers on exploring new thin-film approaches specifically designed for M-III semiconductors. Substantial efficiency gains may be possible by employing light trapping ...

This report describes to examine new solar cell desip approaches for achieving very high conversion efficiencies. The program consists of two elements. The first centers on exploring new thin-film approaches specifically designed for M-III semiconductors. Substantial efficiency gains may be possible by employing light trapping ...

... Analog-to-digital conversion Data conversion ... Page 2. VLSI Circuit Techniques and Technologies for Ultra High Speed Data Conversion Interfaces ...

Efficient second-harmonic generation in a LiB(3)O(5) crystal over the spectral range of a Ti:sapphire laser is demonstrated. The angular acceptance and damage threshold of the LiB(3)O(5) crystal are measured and calculated, and a 30% conversion efficiency is achieved (with a 5-mm-long crystal). The potential for increasing the ...

Biomass can provide a substantial energy source. Liquids are preferred for use as transportation fuels because of their high energy density and handling ease and safety. Liquid fuel production from biomass can be accomplished by any of several different processes including hydrolysis and fermentation of the carbohydrates to alcohol fuels, thermal gasification and synthesis of ...

TiO2:Eu3 + nanorods are hydrothermally grown and used to fabricate a bilayer film electrode in a dye-sensitized solar cell. A light-to-electrical energy conversion efficiency of 8.0% and a quantum efficiency of 93.7% (at 575 nm) is achieved in this solar cell. The high efficiency is due to the improvement of ultraviolet light ...

Phillips Petroleum Co. is poised to license its high conversion process to produce fuel ethers for blending in reformulated gasolines. The technology has been proven in a Phillips semiworks at Bartlesville, Okla. The process can produce methyl tertiary butyl ether, ethyl tertiary butyl ether, tertiary amyl methyl ether, or tertiary amyl ethyl ether with ...

We have conducted parametric economic studies for heavy-ion-beam fusion electric power plants. We examined the effects on the cost of electricity of several design parameters: maximum achievable chamber pulse rate, driver cost, target gain, and electric conversion efficiency, and net electric power. We found with reasonable assumptions on driver cost, ...

A description of spontaneous parametric down-conversion in finite-length one-dimensional nonlinear photonic crystals is developed using semiclassical and quantum approaches. It is shown that if a suitable averaging is added to the semiclassical model, its results are in very good agreement with the quantum approach. We propose two structures made with GaN/AlN that generate ...

An uniquely high conversion efficiency of fundamental radiation from a Ti:sapphire laser to a supercontinuum is achieved through filamentary propagation in sulfur hexafluoride (SF6) to generate a uniform over-octave spectrum. Two different parts of the supercontinuum, firstly around the fundamental wavelength of 800?nm and secondly ...

A high-energy and large-object-spot type cylindrical mirror analyzer (CMA) was constructed with the aid of electron trajectory simulations. By adopting a particular shape for the outer cylinder, an energy resolution of 7% was achieved without guide rings as used in conventional CMAs. Combined with an avalanche photodiode as an electron detector, the ...

The objective of this project is to produce a synthetic crude from coal at a cost lower than $30.00 per barrel (Task A). A second objective, reflecting a recent change in direction in the synthetic fuels effort of DOE, is to produce a fuel which is low in aromatics, yet of sufficiently high octane number for use in the gasoline- burning transportation vehicles of today. To ...

This critical review provides a survey illustrated by recent references of different strategies to achieve a sustainable conversion of biomass to bioproducts. Because of the huge number of chemical products that can be potentially manufactured, a selection of starting materials and targeted chemicals has been done. Also, thermochemical ...

Solar dish/engine systems convert the energy from the sun into electricity at a very high efficiency. Using a mirror array formed into the shape of a dish, the solar dish focuses the sun's rays onto a receiver. The receiver transmits the energy to an engine that generates electric power. Because of the high concentration ratios ...

Solar dish/engine systems convert the energy from the sun into electricity at a very high efficiency. Using a mirror array formed into the shape of a dish, the solar dish focuses the sun`s rays onto a receiver. The receiver transmits the energy to an engine that generates electric power. Because of the high concentration ratios ...

The work presented describes the characteristics of single stage and severed high-efficiency, high-power traveling-wave tube amplifiers operating in {ital X} band at 8.76 GHz. Average amplified output powers of 210 MW have been achieved at 24% efficiency. At high output power levels ({gt}100 MW) sidebands develop ...

The Ra tandem mirror fusion reactor concept features inherent safety, high net plant efficiency, low cost of electricity, low radioactive waste generation, low activation, highly efficient direct conversion, thin radiation shields, and axisymmetric magnets. The safety and environmental features are achieved through ...

In this paper, a numerical study of direct TM{sub 01}{minus}TE{sub 11} mode converters in highly overmoded, bent smooth, circular waveguides is presented for high-power millimeter waves. The various shapes of bent waveguides are elaborately chosen, and their optimized geometrical dimensions have been achieved with a general ...

High resolution beam position monitors (BPM) are an essential tool to achieve and reproduce a low vertical beam emittance at the KEK Accelerator Test Facility (ATF) damping ring. The ATF damping ring (DR) BPMs are currently upgraded with new high resolution read-out electronics. Based on analog and digital ...