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Sample records for capture enhanced fast

  1. Design of a boron neutron capture enhanced fast neutron therapy assembly

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zhonglu

    2006-08-01

    The use of boron neutron capture to boost tumor dose in fast neutron therapy has been investigated at several fast neutron therapy centers worldwide. This treatment is termed boron neutron capture enhanced fast neutron therapy (BNCEFNT). It is a combination of boron neutron capture therapy (BNCT) and fast neutron therapy (FNT). It is believed that BNCEFNT may be useful in the treatment of some radioresistant brain tumors, such as glioblastoma multiform (GBM). A boron neutron capture enhanced fast neutron therapy assembly has been designed for the Fermilab Neutron Therapy Facility (NTF). This assembly uses a tungsten filter and collimator near the patient's head, with a graphite reflector surrounding the head to significantly increase the dose due to boron neutron capture reactions. The assembly was designed using Monte Carlo radiation transport code MCNP version 5 for a standard 20x20 cm{sup 2} treatment beam. The calculated boron dose enhancement at 5.7-cm depth in a water-filled head phantom in the assembly with a 5x5 cm{sup 2} collimation was 21.9% per 100-ppm {sup 10}B for a 5.0-cm tungsten filter and 29.8% for a 8.5-cm tungsten filter. The corresponding dose rate for the 5.0-cm and 8.5-cm thick filters were 0.221 and 0.127 Gy/min, respectively; about 48.5% and 27.9% of the dose rate of the standard 10x10 cm{sup 2} fast neutron treatment beam. To validate the design calculations, a simplified BNCEFNT assembly was built using four lead bricks to form a 5x5 cm{sup 2} collimator. Five 1.0-cm thick 20x20 cm{sup 2} tungsten plates were used to obtain different filter thicknesses and graphite bricks/blocks were used to form a reflector. Measurements of the dose enhancement of the simplified assembly in a water-filled head phantom were performed using a pair of tissue-equivalent ion chambers. One of the ion chambers is loaded with 1000-ppm natural boron (184-ppm {sup 10}B) to measure dose due to boron neutron capture. The measured dose enhancement at 5.0-cm depth

  2. Enhanced image capture through fusion

    Science.gov (United States)

    Burt, Peter J.; Hanna, Keith; Kolczynski, Raymond J.

    1993-01-01

    Image fusion may be used to combine images from different sensors, such as IR and visible cameras, to obtain a single composite with extended information content. Fusion may also be used to combine multiple images from a given sensor to form a composite image in which information of interest is enhanced. We present a general method for performing image fusion and show that this method is effective for diverse fusion applications. We suggest that fusion may provide a powerful tool for enhanced image capture with broad utility in image processing and computer vision.

  3. Boron neutron capture therapy (BNCT) using fast neutrons: Effects in two human tumor cell lines

    International Nuclear Information System (INIS)

    The results demonstrate that the effect of fast neutrons on cell survival in cell culture can be enhanced by boron neutron capture reaction. Even with lower enhancement ratios, the concept of NCT assisted fast neutron therapy may successfully be applied for tumor treatment with the Essen cyclotron. (orig.)

  4. A capture-gated fast neutron detection method

    Science.gov (United States)

    Liu, Yi; Yang, Yi-Gang; Tai, Yang; Zhang, Zhi

    2016-07-01

    To address the problem of the shortage of neutron detectors used in radiation portal monitors (RPMs), caused by the 3He supply crisis, research on a cadmium-based capture-gated fast neutron detector is presented in this paper. The detector is composed of many 1 cm × 1 cm × 20 cm plastic scintillator cuboids covered by 0.1 mm thick film of cadmium. The detector uses cadmium to absorb thermal neutrons and produce capture γ-rays to indicate the detection of neutrons, and uses plastic scintillator to moderate neutrons and register γ-rays. This design removes the volume competing relationship in traditional 3He counter-based fast neutron detectors, which hinders enhancement of the neutron detection efficiency. Detection efficiency of 21.66% ± 1.22% has been achieved with a 40.4 cm × 40.4 cm × 20 cm overall detector volume. This detector can measure both neutrons and γ-rays simultaneously. A small detector (20.2 cm × 20.2 cm × 20 cm) demonstrated a 3.3 % false alarm rate for a 252Cf source with a neutron yield of 1841 n/s from 50 cm away within 15 s measurement time. It also demonstrated a very low (Natural Science Foundation of China (11175098, 11375095)

  5. A Capture-gated Fast Neutron Detection Method

    CERN Document Server

    Liu, Yi; Tai, Yang; Zhang, Zhi

    2016-01-01

    To address the problem of the shortage of neutron detectors used in radiation portal monitors (RPMs), caused by the 3He supply crisis, research on a cadmium-based capture-gated fast neutron detector is presented in this paper. The detector is composed of many 1 cm * 1 cm * 20 cm plastic scintillator cuboids covered by 0.1 mm thick film of cadmium. The detector uses cadmium to absorb thermal neutrons and produce capture gamma-rays to indicate the detection of neutrons, and uses plastic scintillator to moderate neutrons and register gamma-rays. This design removes the volume competing relationship in traditional 3He counter-based fast neutron detectors, which hinders enhancement of the neutron detection efficiency. Detection efficiency of 21.66 +- 1.22% has been achieved with a 40.4 cm * 40.4 cm * 20 cm overall detector volume. This detector can measure both neutrons and gamma-rays simultaneously. A small detector (20.2 cm * 20.2 cm * 20 cm) demonstrated a 3.3 % false alarm rate for a 252Cf source with a neutro...

  6. Integral measurement of fission products capture in fast breeder reactors

    International Nuclear Information System (INIS)

    For the SUPERPHENIX reactor project, it was necessary to know fission products capture with about 10% accuracy in the fast breeder reactor spectra. In this purpose, integral measurements have been carried out on the main separated products by different experimental technics (oscillation, activation and irradiation methods), but particularly on irradiated fuel pins from RAPSODIE and PHENIX reactors in order to directly obtain total effect of fission products. Same tendencies have been observed for both enriched uranium fuel and LMFBR characteristic plutonium fuel. All experimental results have been introduced in CARNAVAL cross section set

  7. The biomechanics of fast prey capture in aquatic bladderworts

    Science.gov (United States)

    Singh, Amit K.; Prabhakar, Sunil; Sane, Sanjay P.

    2011-01-01

    Carnivorous plants match their animal prey for speed of movements and hence offer fascinating insights into the evolution of fast movements in plants. Here, we describe the mechanics of prey capture in aquatic bladderworts Utricularia stellaris, which prey on swimming insect larvae or nematodes to supplement their nitrogen intake. The closed Utricularia bladder develops lower-than-ambient internal pressures by pumping out water from the bladder and thus setting up an elastic instability in bladder walls. When the external sensory trigger hairs on their trapdoor are mechanically stimulated by moving prey, the trapdoor opens within 300–700 μs, causing strong inward flows that trap their prey. The opening time of the bladder trapdoor is faster than any recorded motion in carnivorous plants. Thus, Utricularia have evolved a unique biomechanical system to gain an advantage over their animal prey. PMID:21389013

  8. Enhancing stock returns using hedged dividend capture

    OpenAIRE

    Terry L. Zivney; John H. Ledbetter; James P. Hoban Jr

    2006-01-01

    Purpose – This paper aims to explore the potential use of a dividend capture strategy by individual investors. This strategy arises from the 2003 tax law changes which lowered tax rates on dividends received, while leaving the short-term tax rates on capital losses unchanged. In addition, leverage can be used in combination with an aggressive call-writing strategy to receive a multiple of the tax-advantaged dividend yield without a corresponding increase in risk. Design/methodology/approach -...

  9. Fast neutron capture with a white neutron source

    International Nuclear Information System (INIS)

    A system has been developed at the Los Alamos National Laboratory to measure gamma-rays following fast neutron reactions. The neutron beam is produced by bombarding a thick tantalum target with the 800 MeV proton beam from the LAMPF accelerator. Incident neutron energies, from 1 to over 200 MeV, are determined by their times of flight over a 7.6-m flight path. The gamma-rays are detected in five 7.6 x 7.6-cm cylindrical bismuth germanate (BGO) detectors which span an angular range from 450 to 1450 in the reaction plane. With this system it is possible to simultaneously measure the cross section and angular distribution of gamma-rays as a function of neutron energy. The results for the cross section of the 12C(n,n'γ=4.44 MeV) reaction at 900 and 1250 show good agreement with previous measurements while the complete angular distributions show the need for a large a4 coefficient which was not previously observed. Preliminary results for the 12C(n,n'γ=15.1 MeV) reaction have also been obtained. The data obtained for the 40Ca(n,γ0) reaction in the region of the giant dipole resonance demonstrate the unique capabilities of this system. Future developments to the neutron source which will enhance the capabilities of the system are presented. 14 references

  10. Fast neutron capture in actinide isotopes: recent results from Karlsruhe

    International Nuclear Information System (INIS)

    Capture gamma-ray spectra of 241Am, 240Pu, 242Pu 238U and 197Au were calculated in the framework of the spherical optical model and the statistical model. These spectra were used to correct experimental data for the capture cross sections of 240242Pu and 241Am from relative measurements using a Moxon Rae-detector with graphite converter and 197Au as well as 238U as standards. This correction is required to take into account that the detector efficiency is not exactly proportional to gamma-ray energy. The resulting correction factors proved to be negligible for measurements relative to 238U, whereas they are approx. 3% if gold is used as a standard. The capture cross section of 243Am has been measured in the energy range 10 to 250 keV using kinematically collimated neutrons from the 7Li(p,n) and T(p,n) reaction. The samples are positioned at flight paths of 5 to 7 cm and gold was used as a standard. Capture events were detected by two Moxon-Rae detectors with graphite and bismuth-graphite converters shielded by 0.5 to 2 cm of lead. Fission events were detected by a NE213 liquid scintillator. The present status of the experiment and some preliminary results will be presented

  11. Enhancing the detector for advanced neutron capture experiments

    International Nuclear Information System (INIS)

    The Detector for Advanced Neutron Capture Experiments (DANCE) has been used for extensive studies of neutron capture, gamma decay, photon strength functions, and prompt and delayed fission-gamma emission. Despite these successes, the potential measurements have been limited by the data acquisition hardware. We report on a major upgrade of the DANCE data acquisition that simultaneously enables strait-forward coupling to auxiliary detectors, including high-resolution high-purity germanium detectors and neutron tagging array. The upgrade will enhance the time domain accessible for time-of-flight neutron measurements as well as improve the resolution in the DANCE barium fluoride crystals for photons

  12. The Value of Fast Fashion: Quick Response, Enhanced Design, and Strategic Consumer Behavior

    OpenAIRE

    Cachon, Gérard P.; Robert Swinney

    2011-01-01

    A fast fashion system combines quick response production capabilities with enhanced product design capabilities to both design "hot" products that capture the latest consumer trends and exploit minimal production lead times to match supply with uncertain demand. We develop a model of such a system and compare its performance to three alternative systems: quick-response-only systems, enhanced-design-only systems, and traditional systems (which lack both enhanced design and quick response capab...

  13. FAST DISSOLVING TABLETS: NEEDS TO ENHANCE BIOAVAILABILITY

    OpenAIRE

    Raj Kumari; Chandel Priya; Kapoor Ankita

    2013-01-01

    Oral route is the most important and preferred route for drug administration due to the convenience, ease of administration and patient compliance. Tablet is the most preferred conventional oral unit dosage form. During tablet administration dysphasia is the main problem. Fast dissolving tablets can reduce this problem by dissolving and disintegrating rapidly within few seconds in mouth without water. Fast dissolving tablets become advantageous for those patients which have swallowing problem...

  14. Ultra-high throughput real-time instruments for capturing fast signals and rare events

    Science.gov (United States)

    Buckley, Brandon Walter

    processing. The act of time-stretching effectively boosts the performance of the back-end electronics and digital signal processors. The slowed down signals reach the back-end electronics with reduced bandwidth, and are therefore less affected by high-frequency roll-off and distortion. Time-stretching also increases the effective sampling rate of analog-to-digital converters and reduces aperture jitter, thereby improving resolution. Finally, the instantaneous throughputs of digital signal processors are enhanced by the stretch factor to otherwise unattainable speeds. Leveraging these unique capabilities, TiSER becomes the ideal tool for capturing high-speed signals and characterizing rare phenomena. For this thesis, I have developed techniques to improve the spectral efficiency, bandwidth, and resolution of TiSER using polarization multiplexing, all-optical modulation, and coherent dispersive Fourier transformation. To reduce the latency and improve the data handling capacity, I have also designed and implemented a real-time digital signal processing electronic backend, achieving 1.5 tera-bit per second instantaneous processing throughput. Finally, I will present results from experiments highlighting TiSER's impact in real-world applications. Confocal fluorescence microscopy is the most widely used method for unveiling the molecular composition of biological specimens. However, the weak optical emission of fluorescent probes and the tradeoff between imaging speed and sensitivity is problematic for acquiring blur-free images of fast phenomena and cells flowing at high speed. Here I introduce a new fluorescence imaging modality, which leverages techniques from wireless communication to reach record pixel and frame rates. Termed Fluorescence Imaging using Radio-frequency tagged Emission (FIRE), this new imaging modality is capable of resolving never before seen dynamics in living cells - such as action potentials in neurons and metabolic waves in astrocytes - as well as

  15. Measurements of neutron capture cross section of 237Np for fast neutrons

    International Nuclear Information System (INIS)

    The neutron capture cross section of 237Np has been measured for fast neutrons supplied at the center of the core in the Yayoi reactor. The activation method was used for the measurement, in which the amount of the product 238Np was determined by γ-ray spectroscopy using a Ge detector. The neutron flux at the center of the core calculated by the Monte Carlo simulation code MCNP was renormalized by using the activity of a gold activation foil irradiated simultaneously. The new convention is proposed in this paper to make possible a definite comparison of the integral measurement by the activation method using fast reactor neutrons with differential measurements using accelerator-based neutrons. 'Representative neutron energy' is defined in the convention at which the cross section deduced by the activation measurement has a high sensitivity. The capture cross section of 237Np corresponding to the representative neutron energy was deduced as 0.80±0.04 b at 214±9 keV from the measured reaction rate and the energy dependence of the cross section in the nuclear data library ENDF/B-VII.0. The deduced cross section of 237Np at the representative neutron energy agrees with the evaluated data of ENDF/B-VII.0, but is 15% higher than that of JENDL-3.3 and 13% higher than that of JENDL/AC-2008. (author)

  16. Enhancing the Detector for Advanced Neutron Capture Experiments

    OpenAIRE

    Couture A.; Mosby S.; Baramsai B.; Bredeweg T. A.; Jandel M.; Macon K.; O’Donnell J.M.; Rusev G.; Taddeucci T. N; Ullmann J.L.; Walker C.L.

    2015-01-01

    The Detector for Advanced Neutron Capture Experiments (DANCE) has been used for extensive studies of neutron capture, gamma decay, photon strength functions, and prompt and delayed fission-gamma emission. Despite these successes, the potential measurements have been limited by the data acquisition hardware. We report on a major upgrade of the DANCE data acquisition that simultaneously enables strait-forward coupling to auxiliary detectors, including high-resolution high-purity germanium detec...

  17. Electron capture by fast protons from carbon, neon amd argon in the Coulomb Born approximation

    International Nuclear Information System (INIS)

    The Coulomb Born approximation formulated by imposing the asymptotically exact boundary conditions on the scattering wave-functions and the perturbation potentials is used to compute total cross sections for electron capture by fast protons from carbon, neon and argon atoms at intermediate and high energies. An independent particle model is employed with a one-electron orbital for the multi-electron target atom. Three sets of numerical computations are presented in which the initial state of the active electron is described by either a Roothan-Hartree-Fock wavefunction or a hydrogenic wavefunction with standard or experimentally derived effective charges. The present calculated results are found to be in good agreement with existing experimental data in the intermediate and high energy region. (author)

  18. Role of the TAPIRO fast research reactor in neutron capture therapy in Italy. Calculations and measurements

    International Nuclear Information System (INIS)

    For Neutron Capture Therapy (NCT) applications, many research reactors are presently utilized. Clinical trials are performed in thermal reactors that have been appropriately modified, in order to obtain convenient beams for Becton (Boron Neutron Capture Therapy), by means of proper filtering or spectrum shifting. However, the beam quality obtainable by fast reactors is expected to be better than that of thermal reactor facilities. Tapiro is a low power, high flux, highly enriched (93.5%) 235Uranium fast reactor. The power is 5 kw and the maximum neutron flux in the core is 3.2'1012 cm-2 s-1. A thermal column and an epithermal one have been designed and constructed, aimed at dosimetry and animal experiments. The configurations of the columns have been designed by means of calculations based on Monte Carlo with the codes MCNP4B and MCNPX2.1.5 together with the DSA (Direct Statistical Approach) variance reduction optimisation patch. The columns have been characterized by means of measurements performed with activation techniques and thermoluminescence and gel dosimeters. Experimental results have shown good consistency with calculations. Moreover, they have confirmed the good quality of the beams obtainable with such a reactor. The TAPIRO reactor (a) and the scheme of the epithermal column (b) are shown. To have further confirmation of the quality of the radiation field in the constructed epithermal column, in-phantom absorbed doses have been measured and profiled by means of gel dosimeters, separating the various dose contributions having different biological effects. An epithermal column for human clinical trials has been designed by means of Monte Carlo calculations and the construction is now in progress. A section of this column is shown and beam parameters are reported. It is evident that the beam quality of this column is satisfactory in comparison with the IAEA recommendations. Moreover, such parameters are good if compared with those available at the

  19. Laser irradiated enhancement of the atomic electron capture rate in search of new physics

    International Nuclear Information System (INIS)

    Electron capture processes are important for new physics searches and therefore a high capture rate is inevitably desired. We investigate a possibility of enhancement of an atomic electron capture rate by irradiating laser beam to “an atom”. The possibility of the enhancement is shown as a consequence of an enhanced electron wave function at origin Ψ(0) through an effectively increased mass of the electron. We find that order of magnitude enhancement can be achieved using the laser with intensity 1010 W/mm2, and energy of photon, of O(10-3) eV. (author)

  20. Role of the Tapiro Fast Research Reactor in Neutron Capture Therapy in Italy Calculations and Measurements

    International Nuclear Information System (INIS)

    Thermal-neutron research reactors are currently the most common source of neutron beams for both research and clinical trials of neutron capture therapy (NCT). Neutron spectra suitable for NCT are typically produced either by beam filtering or spectrum shifting techniques. However, fast-neutron reactors are also being considered for NCT application as it is recognized that they may allow for improved beam quality. TAPIRO is a low power, high flux, highly enriched (93.5% 235U) fast reactor. The power is 5 kW and the maximum neutron flux in the core is 3x1012 cm-2.s-1. Both a thermal and an epithermal column have been designed and constructed, aimed at dosimetry and animal experiments. The configurations of the columns have been designed by means of Monte Carlo calculations. The columns have been characterized by means of measurements performed with activation techniques and thermoluminescence and gel dosimeters. Experimental results have shown good consistency with calculations. Moreover, they have confirmed the good quality of the beams obtainable with such a reactor. An epithermal column for clinical trials of patients with brain gliomas has been designed and is under construction. The treatment planning figures-of-merit in an anthropomorphic phantom look very satisfactory. (author)

  1. Design of neutron beams for boron neutron capture therapy in a fast reactor

    International Nuclear Information System (INIS)

    The BNCT (Boron Neutron Capture Therapy) technique makes use of thermal or epithermal neutrons to irradiate tumours previously loaded with 10B. Reactors are currently seen as a suitable neutron source for BNCT implementation, due to the high intensity of the flux they can provide. The TAPIRO reactor, that is located at the ENEA Casaccia Centre near Rome, is a low-power fast-flux research reactor that can be usefully employed for this application. In this work computer simulations were carried out on this reactor to obtain epithermal and thermal neutron beams for the application of BNCT in Italy in the framework of a specific research program. Comparisons with measurements are also reported. Using the MCNP-4B code, Monte Carlo calculations were carried out to determine the materials suitable for the design of the thermal and epithermal columns. Various arrangements of reflector and moderator materials have been investigated to achieve the desired experimental constraints. On the basis of these calculations, a thermal column was designed and installed in the TAPIRO reactor to perform preliminary experiments on small laboratory animals. For the planning of a therapy treatment of gliomas on larger size animals, several material configurations were investigated in the search for an optimal epithermal facility. The aim of the present study is to indicate how a fast research reactor can be successfully modified for generating neutron beams suitable for BNCT applications. (author)

  2. Dosimetry of the low fouence fast neutron beams for boron neutron capture therapy

    International Nuclear Information System (INIS)

    For the research of Boron Neutron Capture Therapy (BNCT), fast neutrons generated from the MC-50 cyclotron with maximum energy of 34.4 MeV in Korea Cancer Center Hospital were moderated by 70 cm paraffin and then the dose characteristics were investigated. Using these results, we hope to establish the protocol about dose measurement of epi-thermal neutron, to make a basis of dose characteristic of epi-thermal neutron emitted from nuclear reactor, and to find feasibility about accelerator-based BNCT. For measuring the absorbed dose and dose distribution of fast neutron beams, we used Unidos 10005 (PTW, Germany) electrometer and IC-17 (Far West, USA), IC-18, EIC-1 ion chambers manufactured by A-150 plastic and used IC-17M ion chamber manufactured by magnesium for gamma dose. There chambers were flushed with tissue equivalent gas and argon gas and then the flow rate was 5 cc per minute. Using Monte Carlo N-Particle (MCNP) code, transport program in mixed field with neutron, photon, electron, two dimensional dose and energy fluence distribution was calculated and, there results were compared with measured results. The absorbed dose of fast neutron beams was 6.47 x 10-3 cGy per 1 MU at the 4 cm depth of the water phantom, which is assumed to be effective depth for BNCT. The magnitude of gamma contamination intermingled with fast neutron beams was 65.2±0.9% at the same depth. In the dose distribution according to the depth or water, the neutron dose decreased linearly and the gamma dose decreased exponentially as the depth was deepened. The factor expressed energy level, D20/DI0, of the total dose was 0.718. Through the direct measurement using the two ion chambers, which is made different wall materials, and computer calculation of isodose distribution using MCNP simulation method, we have found the dose characteristics of low fluence fast neutron beams. If the power supply and the target material, which generate high voltage and current, will be developed and gamma

  3. An enhanced fast scanning algorithm for image segmentation

    Science.gov (United States)

    Ismael, Ahmed Naser; Yusof, Yuhanis binti

    2015-12-01

    Segmentation is an essential and important process that separates an image into regions that have similar characteristics or features. This will transform the image for a better image analysis and evaluation. An important benefit of segmentation is the identification of region of interest in a particular image. Various algorithms have been proposed for image segmentation and this includes the Fast Scanning algorithm which has been employed on food, sport and medical images. It scans all pixels in the image and cluster each pixel according to the upper and left neighbor pixels. The clustering process in Fast Scanning algorithm is performed by merging pixels with similar neighbor based on an identified threshold. Such an approach will lead to a weak reliability and shape matching of the produced segments. This paper proposes an adaptive threshold function to be used in the clustering process of the Fast Scanning algorithm. This function used the gray'value in the image's pixels and variance Also, the level of the image that is more the threshold are converted into intensity values between 0 and 1, and other values are converted into intensity values zero. The proposed enhanced Fast Scanning algorithm is realized on images of the public and private transportation in Iraq. Evaluation is later made by comparing the produced images of proposed algorithm and the standard Fast Scanning algorithm. The results showed that proposed algorithm is faster in terms the time from standard fast scanning.

  4. Surface water mass composition changes captured by cores of Arctic land-fast sea ice

    Science.gov (United States)

    Smith, I. J.; Eicken, H.; Mahoney, A. R.; Van Hale, R.; Gough, A. J.; Fukamachi, Y.; Jones, J.

    2016-04-01

    In the Arctic, land-fast sea ice growth can be influenced by fresher water from rivers and residual summer melt. This paper examines a method to reconstruct changes in water masses using oxygen isotope measurements of sea ice cores. To determine changes in sea water isotope composition over the course of the ice growth period, the output of a sea ice thermodynamic model (driven with reanalysis data, observations of snow depth, and freeze-up dates) is used along with sea ice oxygen isotope measurements and an isotopic fractionation model. Direct measurements of sea ice growth rates are used to validate the output of the sea ice growth model. It is shown that for sea ice formed during the 2011/2012 ice growth season at Barrow, Alaska, large changes in isotopic composition of the ocean waters were captured by the sea ice isotopic composition. Salinity anomalies in the ocean were also tracked by moored instruments. These data indicate episodic advection of meteoric water, having both lower salinity and lower oxygen isotopic composition, during the winter sea ice growth season. Such advection of meteoric water during winter is surprising, as no surface meltwater and no local river discharge should be occurring at this time of year in that area. How accurately changes in water masses as indicated by oxygen isotope composition can be reconstructed using oxygen isotope analysis of sea ice cores is addressed, along with methods/strategies that could be used to further optimize the results. The method described will be useful for winter detection of meteoric water presence in Arctic fast ice regions, which is important for climate studies in a rapidly changing Arctic. Land-fast sea ice effective fractionation coefficients were derived, with a range of +1.82‰ to +2.52‰. Those derived effective fractionation coefficients will be useful for future water mass component proportion calculations. In particular, the equations given can be used to inform choices made when

  5. Enhanced Oil Recovery with CO2 Capture and Sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Andrei, Maria; De Simoni, Michela; Delbianco, Alberto; Cazzani, Piero; Zanibelli, Laura

    2010-09-15

    This paper presents the results of a feasibility study aimed at extending the production life of a small oilfield in Italy through EOR, employing the CO2 captured from the flue gas streams of the refinery nearby. The EOR operation allows the recovery of additional reserves while a consistent amount of the CO2 injected remains permanently stored into the reservoir. The screening process selection for EOR-CO2 and the main elements of the pilot project for the proper upstream-downstream integration will be described. Evaluation of EOR-CO2 extension to other oilfields and its effect on oil production and project's economics will be reported.

  6. Metastable enhancement of C+ and O+ capture reactions

    International Nuclear Information System (INIS)

    Single electron capture by 10- to 500-eV singly charged C and O ions traversing targets of H2 and H was studied with emphasis on comparing cross sections for metastable species with those for the ground state. For an H2 target cross sections are of the order 10 Angstrom and 20 to 30 times larger than for ground state species. Electron impact ion sources typically produce 5 to 30% of their output in the metastable state. Previous published work has largely ignored (or failed to detect) the presence of metastables and is incorrect by as much as an order of magnitude. Discrepancies between data sets have been resolved, and a reliable data set is provided for energies from 10 to 105 eV. Similar experiments for an atomic H target are underway. It is proposed to extend the program to similar studies with multiply charged projectile species

  7. Accelerator-based neutron source for the neutron-capture and fast neutron therapy at hospital

    Science.gov (United States)

    Bayanov, B. F.; Belov, V. P.; Bender, E. D.; Bokhovko, M. V.; Dimov, G. I.; Kononov, V. N.; Kononov, O. E.; Kuksanov, N. K.; Palchikov, V. E.; Pivovarov, V. A.; Salimov, R. A.; Silvestrov, G. I.; Skrinsky, A. N.; Soloviov, N. A.; Taskaev, S. Yu.

    The proton accelerator complex for neutron production in lithium target discussed, which can operate in two modes. The first provides a neutron beam kinematically collimated with good forward direction in 25° and average energy of 30 keV, directly applicable for neutron-capture therapy with high efficiency of proton beam use. The proton energy in this mode is 1.883-1.890 MeV that is near the threshold of the 7Li( p, n) 7Be reaction. In the second mode, at proton energy of 2.5 MeV, the complex-produced neutron beam with maximum energy board of 790 keV which can be used directly for fast neutron therapy and for neutron-capture therapy after moderation. The project of such a neutron source is based on the 2.5 MeV original electrostatic accelerator tandem with vacuum insulation developed at BINP which is supplied with a high-voltage rectifier. The rectifier is produced in BINP as a part of ELV-type industrial accelerator. Design features of the tandem determining its high reliability in operation with a high-current (up to 40 mA) H - ion beam are discussed. They are: the absence of ceramic accelerator columns around the beam passage region, good conditions for pumping out of charge-exchange gaseous target region, strong focusing optics and high acceleration rate minimizing the space charge effects. The possibility of stabilization of protons energy with an accuracy level of 0.1% necessary for operation in the near threshold region is considered. The design description of H - continuous ion source with a current of 40 mA is also performed. To operate with a 100 kW proton beam it is proposed to use liquid-lithium targets. A thin lithium layer on the surface of a tungsten disk cooled intensively by a liquid metal heat carrier is proposed for use in case of the vertical beam, and a flat liquid lithium jet flowing through the narrow nozzle - for the horizontal beam.

  8. Contrast-enhanced fast fluid-attenuated inversion recovery MR imaging in patients with brain tumors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chan Kyo; Na, Dong Gyu; Ryoo, Wook Jae; Byun Hong Sik; Yoon, Hye Kyung; Kim, Jong hyun [Samsung Medical Center, School of Medicine, Sungkyunkwan University, Seoul (Korea, Republic of)

    2000-09-01

    To assess the feasibility of contrast-enhanced fast fluid-attenuated inversion recovery (fast FLAIR) MR imaging in patients with brain tumors. This study involved 31 patients with pathologically proven brain tumors and nine with clinically diagnosed metastases. In all patients, T2-weighted, fast FLAIR, images were visual contrast-enhanced T1-weighted MR images were obtained. Contrast-enhanced fast FLAIR images were visually compared with other MR sequences in terms of tumor conspicuity. In order to distinguish tumor and surrounding edema, contrast-enhanced fast FLAIR images were compared with fast FLAIR and T2-weighted images. The tumor-to- white matter contrast-to-noise ratios (CNRs), as demonstrated by T2-weighted, fast FLAIR, contrast-enhanced fast FLAIR and contrast-enhanced T1-weighted imaging, were quantitatively assessed and compared. For the visual assessment of tumor conspicuity, contrast-enhanced fast FLAIR image imaging superior to fast FLAIR in 60% of cases (24/40), and superior to T2-weighted in 70% (28/40). Contrast-enhanced fast FLAIR imaging was inferior to contrast-enhanced T1-weighted in 58% of cases (23/40). For distinguishing between tumor and surrounding edema, contrast-enhanced fast FLAIR imaging was superior to fast FLAIR or T2-weighted in 22 of 27 tumors with peritumoral edema (81%). Quantitatively, CNR was the highest on contrast-enhanced fast FLAIR image and the lowest on fast FLAIR. For the detection of leptomeningeal metastases, contrast-enhanced fast FLAIR was partially superior to contrast-enhanced T1-weighted imaging in two of three high-grade gliomas. Although contrast-enhanced fast FLAIR imaging should not be seen as a replacement for conventional modalities, it provides additional informaton for assessment of the extent of glial cell tumors and leptomeningeal metastases in patients with brain tumors. (author)

  9. Contrast-enhanced fast fluid-attenuated inversion recovery MR imaging in patients with brain tumors

    International Nuclear Information System (INIS)

    To assess the feasibility of contrast-enhanced fast fluid-attenuated inversion recovery (fast FLAIR) MR imaging in patients with brain tumors. This study involved 31 patients with pathologically proven brain tumors and nine with clinically diagnosed metastases. In all patients, T2-weighted, fast FLAIR, images were visual contrast-enhanced T1-weighted MR images were obtained. Contrast-enhanced fast FLAIR images were visually compared with other MR sequences in terms of tumor conspicuity. In order to distinguish tumor and surrounding edema, contrast-enhanced fast FLAIR images were compared with fast FLAIR and T2-weighted images. The tumor-to- white matter contrast-to-noise ratios (CNRs), as demonstrated by T2-weighted, fast FLAIR, contrast-enhanced fast FLAIR and contrast-enhanced T1-weighted imaging, were quantitatively assessed and compared. For the visual assessment of tumor conspicuity, contrast-enhanced fast FLAIR image imaging superior to fast FLAIR in 60% of cases (24/40), and superior to T2-weighted in 70% (28/40). Contrast-enhanced fast FLAIR imaging was inferior to contrast-enhanced T1-weighted in 58% of cases (23/40). For distinguishing between tumor and surrounding edema, contrast-enhanced fast FLAIR imaging was superior to fast FLAIR or T2-weighted in 22 of 27 tumors with peritumoral edema (81%). Quantitatively, CNR was the highest on contrast-enhanced fast FLAIR image and the lowest on fast FLAIR. For the detection of leptomeningeal metastases, contrast-enhanced fast FLAIR was partially superior to contrast-enhanced T1-weighted imaging in two of three high-grade gliomas. Although contrast-enhanced fast FLAIR imaging should not be seen as a replacement for conventional modalities, it provides additional informaton for assessment of the extent of glial cell tumors and leptomeningeal metastases in patients with brain tumors. (author)

  10. A graphene oxide/amidoxime hydrogel for enhanced uranium capture

    Science.gov (United States)

    Wang, Feihong; Li, Hongpeng; Liu, Qi; Li, Zhanshuang; Li, Rumin; Zhang, Hongsen; Liu, Lianhe; Emelchenko, G. A.; Wang, Jun

    2016-01-01

    The efficient development of selective materials for the recovery of uranium from nuclear waste and seawater is necessary for their potential application in nuclear fuel and the mitigation of nuclear pollution. In this work, a graphene oxide/amidoxime hydrogel (AGH) exhibits a promising adsorption performance for uranium from various aqueous solutions, including simulated seawater. We show high adsorption capacities (Qm = 398.4 mg g-1) and high % removals at ppm or ppb levels in aqueous solutions for uranium species. In the presence of high concentrations of competitive ions such as Mg2+, Ca2+, Ba2+ and Sr2+, AGH displays an enhanced selectivity for uranium. For low uranium concentrations in simulated seawater, AGH binds uranium efficiently and selectively. The results presented here reveal that the AGH is a potential adsorbent for remediating nuclear industrial effluent and adsorbing uranium from seawater.

  11. Security-Enhanced Fast Mobile IPv6 Handover

    Science.gov (United States)

    Park, Chang-Seop

    Motivated by the fact that the existing FMIPv6 security scheme has several weaknesses in terms of security and efficiency, we propose a security-enhanced fast mobile IPv6 in this letter. Based on the concept of a secret key-based CGA (Cryptographically Generated Address), we show how to establish a new security association between the MN and AR (Access Router) whenever a handover occurs. We also show that the proposed scheme is robust against several types of security attacks feasible with the existing scheme. Our scheme is more efficient in that it requires fewer public key operations.

  12. Neutron capture and total cross-section measurements on fast reactor structural materials

    International Nuclear Information System (INIS)

    The neutron capture and total cross-sections of a series of nuclides in the mass range 46 to 62 have been measured at Harwell by the time-of-flight method. The capture cross-sections were measured for incident neutron energies from a few eV to 800 keV using the neutron booster target of the 45 MeV electron linac. High resolution total cross-section measurements were made with the transmission facility on the 160 MeV proton synchrocyclotron. The results of preliminary analyses of the data are presented on the capture cross-sections of Fe, 47Ti, and 49Ti and the total cross-sections of 56Fe, 58Ni and 60Ni. (author)

  13. Radiative electron capture by fast highly stripped heavy ions channeled in a thin crystal

    International Nuclear Information System (INIS)

    Interaction of moving ions with single crystals is known to be very sensitive to the orientation of the incident beam with respect to the crystalline directions of the target. We have shown that channeling conditions strongly modify the slowing down and the charge exchange processes of high energy heavy ions. The reason is that channeled particles are prevented from approaching the target atoms, and then can interact only with loosely bound target electrons. This results not only in drastically reducing the electron density experienced by them, which lowers energy loss and electron loss, but also in inhibiting the radiationless capture of bound electrons, since most of the available electrons are quasi-free valence electrons. In an experiment where high energy Xeq+ ions, with q = 52, 53, 54, are directed onto a thin Si single crystal we observe that, whereas unchanneled ions reach charge equilibrium very rapidly, most channeled ions keep their incident charge state unchanged all along their passage through the crystal. On one hand the loss of their electron(s) (q = 52, 53) is impossible. On the other hand the only way that is left to them to capture quasi-free electrons is the radiative electron capture (REC). This process does occur also for unchanneled ions but is quite difficult to observe, particularly because of the overwhelming non radiative Mechanical Electron Capture(MEC). REC photons have been observed in channeling conditions and correspond to electron capture into the K, L and M shells of the projectiles. The shape of the REC photon lines reflects the momentum distribution of the electron encountered by channeled ions. Channeling offers a unique opportunity to study the radiative electron capture since it allows ions of well defined charge state to travel through a dense quasi-free electron target. This opportunity could be extended to other processes involving high energy heavy ions

  14. Fast and simple purification of chemically modified hammerhead ribozymes using a lipophilic capture tag.

    OpenAIRE

    Sproat, B S; Rupp, T; Menhardt, N; Keane, D.; Beijer, B

    1999-01-01

    A new type of 5'-lipophilic capture tag is described, enabling the facile reverse phase HPLC purification of chemically modified hammerhead ribozymes (oligozymes) whilst still carrying the 2'-O-tert.-butyldimethylsilyl protection of the essential riboses. In its most convenient form, the capture tag consists of a simple diol, such as hexan-1,6-diol, which at one end is attached via a silyl residue to a highly lipophilic entity such as tocopherol (vitamin E) or cholesterol, and the other end i...

  15. Total #betta#-ray spectra and isomeric ratio calculations in fast neutron radiative capture

    International Nuclear Information System (INIS)

    Estimates of total #betta#-ray spectra and isomeric ratios have been attempted in the framework of the optical and statistical models for neutron radiative capture. The role of optical model, of Brink-Axel and Weisskopf assumptions as well as of the most important parameters have been investigated. The results of these calculations satisfactorily agree with experimental information in all cases considered. Spectra calculations were used in relative neutron capture measurements for correction of systematic uncertainties due to non-linear efficiency of the Moxon-Rae detector. Data on the calculated total #betta#-ray spectra and the corresponding integrated cross sections are shown for the isotopes investigated. The impact of parameters involved is discussed

  16. Functionalization of Metal-Organic Frameworks for Enhanced Stability under Humid Carbon Dioxide Capture Conditions.

    Science.gov (United States)

    Andirova, Dinara; Lei, Yu; Zhao, Xiaodan; Choi, Sunho

    2015-10-26

    Metal-organic frameworks (MOFs) have been highlighted recently as promising materials for CO2 capture. However, in practical CO2 capture processes, such as capture from flue gas or ambient air, the adsorption properties of MOFs tend to be harmed by the presence of moisture possibly because of the hydrophilic nature of the coordinatively unsaturated sites (CUSs) within their framework. In this work, the CUSs of the MOF framework are functionalized with amine-containing molecules to prevent structural degradation in a humid environment. Specifically, the framework of the magnesium dioxybenzenedicarboxylate (Mg/DOBDC) MOF was functionalized with ethylenediamine (ED) molecules to make the overall structure less hydrophilic. Structural analysis after exposure to high-temperature steam showed that the ED-functionalized Mg/DOBDC (ED-Mg/DOBDC) is more stable under humid conditions, than Mg/DOBDC, which underwent drastic structural changes. ED-Mg/DOBDC recovered its CO2 adsorption capacity and initial adsorption rate quite well as opposed to the original Mg/DOBDC, which revealed a significant reduction in its capture capacity and kinetics. These results suggest that the amine-functionalization of the CUSs is an effective way to enhance the structural stability of MOFs as well as their capture of humid CO2 . PMID:26367016

  17. CO2 capture enhancement in InOF-1 via the bottleneck effect of confined ethanol.

    Science.gov (United States)

    Peralta, Ricardo A; Campos-Reales-Pineda, Alberto; Pfeiffer, Heriberto; Álvarez, J Raziel; Zárate, J Antonio; Balmaseda, Jorge; González-Zamora, Eduardo; Martínez, Ana; Martínez-Otero, Diego; Jancik, Vojtech; Ibarra, Ilich A

    2016-08-11

    CO2 capture of InOF-1 was enhanced 3.6-fold, at 1 bar and 30 °C, by confining EtOH within its pores. Direct visualisation by single crystal X-ray diffraction revealed that EtOH divides InOF-1 channels in wide sections separated by "bottlenecks" caused by EtOH molecules bonded to the μ2-OH functional groups of InOF-1. PMID:27469274

  18. Formation of Triblock Copolymers via a Tandem Enhanced Spin Capturing-Nitroxide-Mediated Polymerization Reaction Sequence

    OpenAIRE

    Junkers, Thomas; Zang, Lin; Wong, Edgar H. H.; Dingenouts, Nico; Barner-Kowollik, Christopher

    2011-01-01

    The preparation of ABA-type block copolymers via tandem enhanced spin capturing polymerization (ESCP) and nitroxide-mediated polymerization (NMP) processes is explored in-depth. Midchain alkoxyamine functional polystyrenes (M(n) = 6200, 12,500 and 19,900 g mol(-1)) were chain extended with styrene as well as tert-butyl acrylate at elevated temperature NMP conditions (T = 110 degrees C) generating a tandem ESCP-NMP sequence. Although the chain extensions and thus the block copolymer formation ...

  19. Fast contrast-enhanced MR whole-brain venography

    Energy Technology Data Exchange (ETDEWEB)

    Loevblad, Karl-Olof; Schneider, Jacques; El-Koussy, Marwan; Guzman, Raphael; Heid, Oliver; Remonda, Luca; Schroth, Gerhard [Department of Neuroradiology, Inselspital, University of Berne, Berne (Switzerland); Bassetti, Claudio [Department of Neurology, Inselspital, University of Berne, Berne (Switzerland)

    2002-08-01

    Our aim was to assess the value of a new fast contrast-enhanced MR venography (CE-MRV) sequence in the investigation of normal and diseased cerebral veins. Conventional time-of-flight (TOF) MRV is time consuming, with imaging for a single sequence taking many minutes. MRI was performed with a clinical 1.5-T scanner; conventional TOF MRV followed by CE-MRV was performed using a modified 3D first-pass MR angiography sequence. Ten control subjects without cerebral pathology were studied as well as ten patients with cerebral venous thrombosis for a total of 20 studies with both sequences. CE-MRV was able to provide a set of complete MRV images in a significantly shorter time than conventional MRV sequencing could. The field of view also provided greater coverage of the vessels of the head and neck. CE-MRV also provided more extensive small vein detail and provided a better demonstration of intraluminal defects, despite a slightly lower resolution. Both methods were equally suited for the demonstration of venous thrombosis and demonstrated all cases equally well; however, CE-MRV provided more detailed information by showing partially obstructed sinuses and by showing better the presence of cortical collateral venous drainage. (orig.)

  20. Measurements of fast neutron capture and fission cross sections of minor actinide isotopes

    International Nuclear Information System (INIS)

    The neutron capture cross sections of 240Pu, 242Pu and 241Am were measured in the energy range from 10 to 250 keV, with 197Au and 238U as standards. The subthreshold fission cross sections of 240Pu and 241Am were determined relative to 235U in the energy range from 10 to 250 keV and 10 keV to 1 MeV, respectively. Continuous neutron spectra and in one case monoenergetic neutrons were produced by means of the Li(p,n) and T(p,n) reactions with the Karlsruhe 3-MV pulsed Van de Graaff accelerator. Capture events were detected by a Moxon Rae detector, and fission events, observed with a NE213 liquid scintillator. The high neutron flux available at flight paths as short as 50 to 135 mm allowed a statistical accuracy of 1 to 3% for most of the measured data together with a moderate energy resolution of 10 to 30 ns/m. An overall uncertainty between 5 and 10% was obtained in most of the measurements. A comparison is made to recent data of other authors and to evaluated files. 8 figures, 1 table

  1. Fast-neutron capture cross sections of importance in technological applications

    International Nuclear Information System (INIS)

    The importance of the capture cross section of the major fertile nuclei, 238U and 232Th, leads to the consideration of these data. The 238U (n,γ) cross section is considered of priority as it is part of the 238U-239Pu cycle. Experimental techniques used in the measurements of these data are considered. Data measured more recently are compared with provisions made for the possible explanations of differing results. It is concluded that the 238U (n,γ) cross section is known with approx. 5% above 10 keV and fulfills the uncertainty limit for this cross section set to achieve design accuracy for k/sub eff/ and the breeding ratio above 500 keV. Below 500 keV, the present uncertainty falls short of the required 1.5 to 3.0% uncertainty. Specific recommendations are made to resolve existing discrepancies and data uncertainties. 84 references

  2. The Wavenumber Algorithm: Fast Fourier-Domain Imaging Using Full Matrix Capture

    Science.gov (United States)

    Hunter, A. J.; Drinkwater, B. W.; Wilcox, P. D.

    2009-03-01

    We develop a Fourier-domain approach to full matrix imaging based on the wavenumber algorithm used in synthetic aperture radar and sonar. The extension to the wavenumber algorithm for full matrix capture is described and the performance of the new algorithm is compared to the total focusing method (TFM), which we use as a representative benchmark for the time-domain algorithms. The wavenumber algorithm provides a mathematically rigorous solution to the inverse problem for the assumed forward wave propagation model, whereas the TFM employs heuristic delay-and-sum beamforming. Consequently, the wavenumber algorithm has an improved point-spread function and provides better imagery. However, the major advantage of the wavenumber algorithm is its superior computational performance. For large arrays and images, the wavenumber algorithm is several orders of magnitude faster than the TFM. On the other hand, the key advantage of the TFM is its flexibility. The wavenumber algorithm requires a regularly sampled linear array, while the TFM can handle arbitrary imaging geometries. The TFM and the wavenumber algorithm are compared using simulated and experimental data.

  3. Development of a dual phantom technique for measuring the fast neutron component of dose in boron neutron capture therapy

    Energy Technology Data Exchange (ETDEWEB)

    Sakurai, Yoshinori, E-mail: yosakura@rri.kyoto-u.ac.jp; Tanaka, Hiroki; Kondo, Natsuko; Kinashi, Yuko; Suzuki, Minoru; Masunaga, Shinichiro; Ono, Koji; Maruhashi, Akira [Kyoto University Research Reactor Institute, Asashironishi 2-1010, Kumatori-cho, Sennan-gun, Osaka 590-0494 (Japan)

    2015-11-15

    Purpose: Research and development of various accelerator-based irradiation systems for boron neutron capture therapy (BNCT) is underway throughout the world. Many of these systems are nearing or have started clinical trials. Before the start of treatment with BNCT, the relative biological effectiveness (RBE) for the fast neutrons (over 10 keV) incident to the irradiation field must be estimated. Measurements of RBE are typically performed by biological experiments with a phantom. Although the dose deposition due to secondary gamma rays is dominant, the relative contributions of thermal neutrons (below 0.5 eV) and fast neutrons are virtually equivalent under typical irradiation conditions in a water and/or acrylic phantom. Uniform contributions to the dose deposited from thermal and fast neutrons are based in part on relatively inaccurate dose information for fast neutrons. This study sought to improve the accuracy in the dose estimation for fast neutrons by using two phantoms made of different materials in which the dose components can be separated according to differences in the interaction cross sections. The development of a “dual phantom technique” for measuring the fast neutron component of dose is reported. Methods: One phantom was filled with pure water. The other phantom was filled with a water solution of lithium hydroxide (LiOH) capitalizing on the absorbing characteristics of lithium-6 (Li-6) for thermal neutrons. Monte Carlo simulations were used to determine the ideal mixing ratio of Li-6 in LiOH solution. Changes in the depth dose distributions for each respective dose component along the central beam axis were used to assess the LiOH concentration at the 0, 0.001, 0.01, 0.1, 1, and 10 wt. % levels. Simulations were also performed with the phantom filled with 10 wt. % {sup 6}LiOH solution for 95%-enriched Li-6. A phantom was constructed containing 10 wt. % {sup 6}LiOH solution based on the simulation results. Experimental characterization of the

  4. The intermediate neutron-capture process and carbon-enhanced metal-poor stars

    CERN Document Server

    Hampel, Melanie; Lugaro, Maria; Meyer, Bradley S

    2016-01-01

    Carbon-enhanced metal-poor (CEMP) stars in the Galactic Halo display enrichments in heavy elements associated with either the s (slow) or the r (rapid) neutron-capture process (e.g., barium and europium respectively), and in some cases they display evidence of both. The abundance patterns of these CEMP-s/r stars, which show both Ba and Eu enrichment, are particularly puzzling since the s and the r processes require neutron densities that are more than ten orders of magnitude apart, and hence are thought to occur in very different stellar sites with very different physical conditions. We investigate whether the abundance patterns of CEMP-s/r stars can arise from the nucleosynthesis of the intermediate neutron-capture process (the i process), which is characterised by neutron densities between those of the s and the r processes. Using nuclear network calculations, we study neutron capture nucleosynthesis at different constant neutron densities n ranging from $10^7$ to $10^{15}$ cm$^{-3}$. With respect to the cl...

  5. Evaluation of the dose enhancement of combined 10B + 157Gd Neutron Capture Therapy (NCT)

    International Nuclear Information System (INIS)

    An innovative molecule, GdBLDL, for boron neutron capture therapy (BNCT) has been developed and its effectiveness as a BNCT carrier is currently under evaluation using in vivo experiments on small animal tumour models. The molecule contains both 10B (the most commonly used NCT agent) and 157Gd nuclei. 157Gd is the second most studied element to perform NCT, mainly thanks to its high cross section for the capture of low-energy neutrons. The main drawback of 157Gd neutron capture reaction is the very short range and low-energy secondary charged particles (Auger electrons), which requires 157Gd to be very close to the cellular DNA to have an appreciable biological effect. Treatment doses were calculated by Monte Carlo simulations to ensure the optimised tumour irradiation and the sparing of the healthy organs of the irradiated animals. The enhancement of the absorbed dose due to the simultaneous presence of 10B and 157Gd in the experimental set-up was calculated and the advantage introduced by the presence of 157Gd was discussed. (authors)

  6. Integrated Mid-Continent Carbon Capture, Sequestration & Enhanced Oil Recovery Project

    Energy Technology Data Exchange (ETDEWEB)

    Brian McPherson

    2010-08-31

    A consortium of research partners led by the Southwest Regional Partnership on Carbon Sequestration and industry partners, including CAP CO2 LLC, Blue Source LLC, Coffeyville Resources, Nitrogen Fertilizers LLC, Ash Grove Cement Company, Kansas Ethanol LLC, Headwaters Clean Carbon Services, Black & Veatch, and Schlumberger Carbon Services, conducted a feasibility study of a large-scale CCS commercialization project that included large-scale CO{sub 2} sources. The overall objective of this project, entitled the 'Integrated Mid-Continent Carbon Capture, Sequestration and Enhanced Oil Recovery Project' was to design an integrated system of US mid-continent industrial CO{sub 2} sources with CO{sub 2} capture, and geologic sequestration in deep saline formations and in oil field reservoirs with concomitant EOR. Findings of this project suggest that deep saline sequestration in the mid-continent region is not feasible without major financial incentives, such as tax credits or otherwise, that do not exist at this time. However, results of the analysis suggest that enhanced oil recovery with carbon sequestration is indeed feasible and practical for specific types of geologic settings in the Midwestern U.S.

  7. IAEA Technical Meeting on Innovative Fast Reactor Designs with Enhanced Negative Reactivity Feedback Features. Presentations

    International Nuclear Information System (INIS)

    The objective of the TM is to review and discuss the safety characteristics and the performances of the core of innovative fast reactor concepts, as well as to present the ongoing R&D activities in the area of core design and advanced simulation tools and methods for fast reactor core physics analysis. The focus is on fast spectrum cores optimized for actinide utilization and transmutation and, in particular, on core designs with enhanced negative reactivity feedback effects

  8. IAEA Technical Meeting on Innovative Fast Reactor Designs with Enhanced Negative Reactivity Feedback Features. Working Material

    International Nuclear Information System (INIS)

    The objective of the TM was to review and discuss the safety characteristics and the performances of the core of innovative fast reactor concepts, as well as to present the ongoing R&D activities in the area of core design and advanced simulation tools and methods for fast reactor core physics analysis. The focus was on fast spectrum cores optimized for actinide utilization and transmutation and, in particular, on core designs with enhanced negative reactivity feedback effects

  9. Environmental and thermodynamic evaluation of CO2 capture, transport and storage with and without enhanced resource recovery

    International Nuclear Information System (INIS)

    This study evaluates the environmental and thermodynamic performance of six coal-fired power plants with CO2 capture and storage. The technologies examined are post-combustion capture using monoethanolamine, membrane separation, cryogenic fractionation and pressure swing adsorption, pre-combustion capture through coal gasification, and capture performing conventional oxy-fuel combustion. The incorporation of CO2 capture is evaluated both on its own and in combination with CO2 transport and geological storage, with and without beneficial use. Overall, we find that pre-combustion CO2 capture and post-combustion through membrane separation present relatively low life-cycle environmental impacts and high exergetic efficiencies. When accounting for transport and storage, the environmental impacts increase and the efficiencies decrease. However, a better environmental performance can be achieved for CO2 capture, transport and storage when incorporating beneficial use through enhanced oil recovery. The performance with enhanced coal-bed methane recovery, on the other hand, depends on the impact categories evaluated. The incorporation of methane recovery results in a better thermodynamic performance, when compared to the incorporation of oil recovery. The cumulative energy demand shows that the integration of enhanced resource recovery strategies is necessary to attain favourable life-cycle energy balances. - Highlights: ► Evaluation of six different CO2 capture technologies for coal-fired power plants. ► Calculation of life-cycle environmental impacts and exergetic efficiencies. ► Suitability of post-combustion capture with membrane separation. ► Suitability of pre-combustion capture through coal gasification. ► Improved performance when incorporating enhanced resource recovery

  10. Enhanced feedback effects in sodium cooled fast reactors using moderating material. The effect of the plutonium content in the fuel

    International Nuclear Information System (INIS)

    The use of fine distributed moderating material to enhance the negative feedback effects and to reduce the sodium void affecting sodium cooled fast reactor cores is described. The influence of the moderating material on the neutron spectrum is given and evaluated through impact on the capture cross sections of major materials (U-238, Pu-239, and Pu-240). The influence of the variation of the Pu content on the efficiency of the enhancement of the Doppler effect and on the reduction of the positive coolant and sodium void effect in a representative SFR fuel assembly configuration is analyzed. Additionally the influence of the moderating material combined with the variation of the Pu content on the infinite multiplication factor is studied. (author)

  11. Experimental determination of neutron capture cross sections of fast reactor structure materials integrated in intermediate energy spectra. Vol. 2: description of experimental structure

    International Nuclear Information System (INIS)

    A selection of technical documents is given concerning the experimental determination of the neutron capture cross-sections of fast reactor structural materials (Fe, Cr, Ni...) integrated over the intermediate energy spectra. The experimental structure project and modifications of the reactor RB2 for this experiment, together with criticality and safety calculations, are presented

  12. γ-Flash suppression using a gated photomultiplier assembled with an LaBr3(Ce) detector to measure fast neutron capture reactions

    International Nuclear Information System (INIS)

    A gated photomultiplier tube (PMT) assembled with an LaBr3(Ce) detector was applied toward the prompt γ{/hbox-}ray measurement of fast neutron capture reactions. Time-of-flight measurements of the neutron capture reactions of Cl and Al were performed using the 46-MeV electron linear accelerator at the Kyoto University Research Reactor Institute (KURRI) as a pulsed neutron source. The photomultiplier gating technique effectively suppressed the saturation of the PMT output and extended the energy region of the TOF measurement. -- Highlights: • Prompt $/gamma$-ray measurements of fast neutron capture reaction. • An LaBr$3$(Ce) detector is used with a gated voltage divider. • The photomultiplier gating technique is applied to the detector. • The effect of the intense $/gamma$ flash is suppressed. • The measured TOF spectrum extends toward faster neutron energy region

  13. Experimental Transport Benchmarks for Physical Dosimetry to Support Development of Fast-Neutron Therapy with Neutron Capture Augmentation

    Energy Technology Data Exchange (ETDEWEB)

    D. W. Nigg; J. K. Hartwell; J. R. Venhuizen; C. A. Wemple; R. Risler; G. E. Laramore; W. Sauerwein; G. Hudepohl; A. Lennox

    2006-06-01

    The Idaho National Laboratory (INL), the University of Washington (UW) Neutron Therapy Center, the University of Essen (Germany) Neutron Therapy Clinic, and the Northern Illinois University(NIU) Institute for Neutron Therapy at Fermilab have been collaborating in the development of fast-neutron therapy (FNT) with concurrent neutron capture (NCT) augmentation [1,2]. As part of this effort, we have conducted measurements to produce suitable benchmark data as an aid in validation of advanced three-dimensional treatment planning methodologies required for successful administration of FNT/NCT. Free-beam spectral measurements as well as phantom measurements with Lucite{trademark} cylinders using thermal, resonance, and threshold activation foil techniques have now been completed at all three clinical accelerator facilities. The same protocol was used for all measurements to facilitate intercomparison of data. The results will be useful for further detailed characterization of the neutron beams of interest as well as for validation of various charged particle and neutron transport codes and methodologies for FNT/NCT computational dosimetry, such as MCNP [3], LAHET [4], and MINERVA [5].

  14. Fast Diagnosis of Gonorrhea Witth Enhanced Luminescence Enzyme Immunoassay

    Institute of Scientific and Technical Information of China (English)

    ZHENG Heyi(郑和义); CAO Jingjiang(曹经江); SHAO Yanglin(邵燕玲)

    2002-01-01

    Objective:To evaluate the value of enhanced luminescence enzyme immunoassay in the diagnosis of Neisseria gonorrhea(NG) infection.Methods: Anti-catalase antibody for Neisseria gonorrheae combined with enhanced luminescence enzyme immunoassay were used to test for N. Gonorrhea.Results: A minimum of 1x104/CFU of GC in genital tract secretions or urine could be detected with the technique of luminescence enzyme immunoassay.Conclusion : The enhanced luninescence enzyme immunoassay has the advantage of high sensitivity and specificity for diagnosing NG from genitourinary tract secretion and urine.

  15. Microbially enhanced carbon capture and storage - from pores to cores (Invited)

    Science.gov (United States)

    Mitchell, A. C.; Cunningham, A. B.; Spangler, L.; Gerlach, R.

    2010-12-01

    During the operation of Geologic Carbon Capture and Storage (CCS) and the injection of supercritical CO2 into underground formations, microbe-rock-fluid interactions occur. These interactions may be important for controlling the ultimate fate of the injected CO2, and may also be manipulated to enhance the storage of the CO2, via mineral-trapping, solubility trapping, formation trapping, and leakage reduction. We have demonstrated that engineered microbial biofilms are capable of enhancing formation, mineral, and solubility trapping in carbon sequestration-relevant formation materials. Batch and flow experiments at atmospheric and high pressures (> 74 bar) have shown the ability of microbial biofilms to decrease the permeability of natural and artificial porous media, survive the exposure to supercritical CO2, and facilitate the conversion of gaseous and supercritical CO2 into long-term stable carbonate phases as well as increase the solubility of CO2 in brines. Ongoing microscopy and modelling studies aim to understand these processes at both the pore- and core-scale in order to facilitate larger scale understanding and potential manipulation for biologically based CCS engineering. Successful development of these biologically-based concepts could result in microbially enhanced carbon sequestration strategies as well as CO2 leakage mitigation technologies, which can be applied either before CO2 injection or as a remedial measure around injection wells.

  16. Power generation enhancement in novel microbial carbon capture cells with immobilized Chlorella vulgaris

    Science.gov (United States)

    Zhou, Minghua; He, Huanhuan; Jin, Tao; Wang, Hongyu

    2012-09-01

    With the increasing concerns for global climate change, a sustainable, efficient and renewable energy production from wastewater is imperative. In this study, a novel microbial carbon capture cell (MCC), is constructed for the first time by the introduction of immobilized microalgae (Chlorella vulgaris) into the cathode chamber of microbial fuel cells (MFCs) to fulfill the zero discharge of carbon dioxide. This process can achieve an 84.8% COD removal, and simultaneously the maximum power density can reach 2485.35 mW m-3 at a current density of 7.9 A m-3 and the Coulombic efficiency is 9.40%, which are 88% and 57.7% greater than that with suspended C. vulgaris, respectively. These enhancements in performance demonstrate the feasibility of an economical and effective approach for the simultaneous wastewater treatment, electricity generation and biodiesel production from microalgae.

  17. Development of an Electronic Research Permissions Management System to Enhance Informed Consents and Capture Research Authorizations Data

    OpenAIRE

    Obeid, Jihad S; Gerken, Katherine; Madathil, Kapil Chalil; Rugg, Daniel; Alstad, Colin E; Fryar, Katrina; Alexander, Randall; Gramopadhye, Anand K; Moskowitz, Jay; Sanderson, Iain C

    2013-01-01

    Informed consents are a critical and essential component of the clinical research process. Currently, most consents and research privacy authorizations are being captured on paper. In this paper we describe a novel method of capturing this information electronically. The objective is to allow easier tracking of research participants’ intent for current and future research involvement, enhance consent comprehension and facilitate the research workflow. After multidisciplinary analysis in key h...

  18. BNCT enhanced fast neutron therapy: in vitro studies for preparing a clinical trial at the Essen cyclotron

    International Nuclear Information System (INIS)

    At the University Hospital Essen a cyclotron producing d(14)+Be fast neutrons is used routinely for patient treatment. Fast neutrons have demonstrated their potential to sterilize glioblastoma but could not show a clinical benefit because of lethal damages to healthy brain. At depth, fast neutrons are thermalized allowing neutron capture reactions, which can be used to enhance the applied dose. A selective increase of the dose to the tumor cells by BNCT may offer a chance to an effective treatment. In order to prepare a clinical trial in vitro experiments were performed. MeWo cells were irradiated in a tissue equivalent phantom at a depth of 6.5 cm. 91% 10B enriched BSH was used to generate BNC effects. For a total dose of 1 Gy the thermal fluence rate was 3.4x1010 cm-2. An amount of 960 ppm 10B present in the cell medium during irradiation led to a reduction of the cell survival from 3.6% (neutron alone) to 0.2%. If the irradiation was performed after incubation of the cells in BSH, but in a medium without BSH the survival was 1.6%. The in vitro set up demonstrates the capacity of BSH to considerably increase the biological effects of the neutron irradiation and add arguments for the opening of a clinical trial. (author)

  19. Sonoporation as an enhancing method for boron neutron capture therapy for squamous cell carcinomas

    International Nuclear Information System (INIS)

    Boron neutron capture therapy (BNCT) is a selective radiotherapy that is dependent on the accumulation of 10B compound in tumors. Low-intensity ultrasound produces a transient pore on cell membranes, sonoporation, which enables extracellular materials to enter cells. The effect of sonoporation on BNCT was examined in oral squamous cell carcinoma (SCC) xenografts in nude mice. Tumor-bearing mice were administrated boronophenylalanine (BPA) or boronocaptate sodium (BSH) intraperitoneally. Two hours later, tumors were subjected to sonoporation using microbubbles followed by neutron irradiation. The 10B concentration was higher in tumors treated with sonoporation than in untreated tumors, although the difference was not significant in BPA. When tumors in mice that received BPA intraperitoneally were treated with sonoporation followed by exposure to thermal neutrons, tumor volume was markedly reduced and the survival rate was prolonged. Such enhancements by sonoporation were not observed in mice treated with BSH-mediated BNCT. These results indicate that sonoporation enhances the efficiency of BPA-mediated BNCT for oral SCC. Sonoporation may modulate the microlocalization of BPA and BSH in tumors and increase their intracellular levels

  20. Fluid flow and mass transfer characteristics of enhanced CO2 capture in a minichannel reactor

    International Nuclear Information System (INIS)

    Highlights: • Enhanced CO2 capture using aqueous DEA in a microreactor. • Observed flow patterns and calculated interfacial area by high-speed visualization. • Achieved close to 100% absorption efficiency under certain operating conditions. • Compared pressure drop and Sherwood number with predictions from model. • Mass transfer coefficient 2–4 orders of magnitude higher than conventional reactors. - Abstract: CO2 absorption using amine solvents can be significantly enhanced by the use of microscale reactors having high surface area to volume ratio. The present paper reports an experimental investigation of the fluid flow and mass transfer characteristics during reactive gas–liquid absorption in a minichannel reactor. Absorption of CO2 mixed with N2 into aqueous diethanolamine was studied in a channel having hydraulic diameter of 762 μm and a circular cross-sectional geometry. High-speed imaging of the two-phase flow was conducted to visualize the flow regimes. Image-processing analysis of the acquired flow patterns was performed to determine the interfacial area. The performance of the reactor was studied with respect to the absorption efficiency, pressure drop, mass transfer coefficient, interfacial area, enhancement factor, and Sherwood number. Parametric studies investigating the effects of phase superficial velocity, liquid reactant concentration, and CO2 concentration in the gas phase were performed and are discussed. High levels of absorption efficiency, close to 100%, were observed under certain operating conditions. An empirical model for the Sherwood number was developed and compared against experimental data. The mass transfer coefficient was found to be higher at reduced channel lengths, which was attributed to improved utilization of the absorption capacity of the amine solution for a given reactor volume. The presently achieved values of mass transfer coefficient and specific interfacial area are between 1 and 4 orders of magnitude

  1. Fast-Valving of Large Steam Turbine Units as a Means of Power System Security Enhancement

    Directory of Open Access Journals (Sweden)

    Bogdan Sobczak

    2014-03-01

    Full Text Available Fast-valving assists in maintaining system stability following a severe transmission system fault by reducing the turbine mechanical power. Fast-valving consists in rapid closing and opening of steam valves in an adequate manner to reduce the generator accelerating power following the recognition of a severe fault. FV can be an effective and economical method of meeting the performance requirements of a power system in the presence of an increase in wind and solar generation in the power system, newly connected large thermal units and delaying of building new transmission lines. The principle of fast-valving and advantages of applying this technique in large steam turbine units was presented in the paper. Effectiveness of fast-valving in enhancing the stability of the Polish Power Grid was analyzed. The feasibility study of fast-valving application in the 560 MW unit in Kozienice Power Station (EW SA was discussed.

  2. Enhancing biogas production of corn stover by fast pyrolysis pretreatment.

    Science.gov (United States)

    Wang, Fang; Zhang, Deli; Wu, Houkai; Yi, Weiming; Fu, Peng; Li, Yongjun; Li, Zhihe

    2016-10-01

    A new thermo-chemical pretreatment by a lower temperature fast pyrolysis (LTFP) was applied to promote anaerobic digestion (AD) efficiency of corn stover (CS). The pretreatment experiment was performed by a fluidized bed pyrolysis reactor at 180, 200 and 220°C with a carrier gas flow rate of 4 and 3m(3)/h. The components characteristics, Scanning Electron Microscope (SEM) images and Crystal Intensity (CrI) of the pretreated CS were tested to explore effectiveness of the pretreatment. The results showed that the cumulative methane production at 180°C for 4 and 3m(3)/h were 199.8 and 200.3mL/g TS, respectively. As compared to the untreated CS, the LTFP pretreatment significantly (a<0.05) increased the methane production by 18.07% and 18.33%, respectively. Methane production was well fitted by the Gompertz models, and the maximum methane potential and AD efficiency was obtained at 180°C for 3m(3)/h. PMID:27420161

  3. Acoustic Waves: A Route to Enhance Sodium Fast Reactor Safety

    International Nuclear Information System (INIS)

    The properties of sodium – both thermohydraulic and neutronic – offer a number of advantages when used as a coolant for fourth generation fast reactors. However, the opacity of sodium is a major drawback for the instrumentation. Acoustic waves could be an efficient means to sound this medium. An ultrasonic telemetry instrument called SONAR was used in the Phénix reactor to detect core movement, to check for missing objects and for sub-assembly handling. Acoustic methods were also used in Superphenix and considered for the EFR project as one of the monitoring solutions to detect anomalies. This paper focuses on the efforts made to develop acoustic techniques to meet the system protection and monitoring requirements. It covers various fields: the development of ultrasonic transducers such as the high-temperature ultrasonic transducer (TUSHT) which have recently been re-developed and manufactured, and current research on instrumentation methods using acoustic transducers for ASTRID. This paper discusses the development of acoustic-based instrument techniques as a means to strengthen the primary and secondary sodium system monitoring approach. In the case of TUSHTs, for example, the potential uses are: core monitoring during nominal operation, the detection of core meltdown accident initiators and fuel handling guidance. (author)

  4. Enhancing slow and fast light effects in quantum dot semiconductor waveguides through ultrafast dynamics

    DEFF Research Database (Denmark)

    Chen, Yaohui; Mørk, Jesper

    2010-01-01

    We show that ultrafast carrier dynamics plays an important role on slow and fast light effects based on coherent population oscillations in quantum dot semiconductor waveguides. Fast light in the gain regime and slow light in the absorption regime are found to be enhanced at frequencies beyond the...... usual limits of the carrier lifetime. The effects are investigated by a comprehensive model and shown to originate from non-equilibrium dynamics within the quantum dot carrier populations....

  5. Enhancing Protein Capture Using a Combination of Nanoyeast Single-Chain Fragment Affinity Reagents and Alternating Current Electrohydrodynamic Forces.

    Science.gov (United States)

    Vaidyanathan, Ramanathan; Rauf, Sakandar; Grewal, Yadveer S; Spadafora, Lauren J; Shiddiky, Muhammad J A; Cangelosi, Gerard A; Trau, Matt

    2015-12-01

    New high-performance detection technologies and more robust protein capture agents can be combined to both rapidly and specifically capture and detect protein biomarkers associated with disease in complex biological samples. Here we demonstrate the use of recently developed recombinant affinity reagents, namely nanoyeast-scFv, in combination with alternating current electrohydrodynamic (ac-EHD)-induced shear forces, to enhance capture performance during protein biomarker analysis. The use of ac-EHD significantly improves fluid transport across the capture domain, resulting in enhanced sensor-target interaction and simultaneous displacement of nonspecific molecules from the electrode surface. We demonstrate this simple proof-of-concept approach for the capture and detection of Entamoeba histolytica antigens from disinfected stool, within a span of 5 min using an ac-EHD microfluidic device. Under an ac-EHD field, antigens were captured on a nanoyeast-scFv immobilized device and subsequently detected using a quantum dot conjugated antibody. This immunosensor specifically detected antigen in disinfected stool with low background noise at concentrations down to 58.8 fM with an interassay reproducibility (%RSD of n = 3) gold electrodes in disinfected stool. We predict this rapid and sensitive approach using these stable affinity reagents may offer a new methodology to detect protein disease biomarkers from biological matrices. PMID:26551436

  6. Hardware Assisted Fast Volume Rendering with Boundary Enhancement

    Institute of Scientific and Technical Information of China (English)

    童欣; 唐泽圣

    1998-01-01

    In this paper,a new volume rendering method with boundary enhancement is presented.The boundary is extracted and represented by surfaces explicitly,Then,using 3D texture mapping and graphics acceleation hardware,the volume data can be rendered with controllable boundary shading effect almost in real time.Test shows that this method is 4-5 times faster than the previous methods.Moreover,it can also be extended to render the surfaces and the volumetric data together interactively.

  7. Transient fasting enhances replication of oncolytic herpes simplex virus in glioblastoma

    Science.gov (United States)

    Esaki, Shinichi; Rabkin, Samuel D; Martuza, Robert L; Wakimoto, Hiroaki

    2016-01-01

    Short-term nutritional restriction (fasting) has been shown to enhance the efficacy of chemotherapy by sensitizing cancer cells and protecting normal cells in a variety of cancer models, including glioblastoma (GBM). Cancer cells, unlike normal cells, respond to fasting by promoting oncogenic signaling and protein synthesis. We hypothesized that fasting would increase the replication of oncolytic herpes simplex virus (oHSV) in GBM. Patient-derived GBM cell lines were fasted by growth in glucose and fetal calf serum restricted culture medium. “Transient fasting”, 24-hour fasting followed by 24-hour recovery in complete medium, increased late virus gene expression and G47Δ yields about 2-fold in GBM cells, but not in human astrocytes, and enhanced G47Δ killing of GBM cells. Mechanistically, “transient fasting” suppressed phosphorylation of the subunit of eukaryotic initiation factor 2α (eIF2α) and c-Jun N-terminal kinases (JNK) in GBM cells, but not in astrocytes. Pharmacological inhibition of JNK also increased G47Δ yield. In vivo, transient fasting (48-hour food restriction and 24-hour recovery) doubled luciferase activity after intratumoral G47Δ-US11fluc injection into orthotopic GBM xenografts. Thus, “transient fasting” increases G47Δ replication and oncolytic activity in human GBM cells. These results suggest that “transient fasting” may be effectively combined to enhance oncolytic HSV therapy of GBM. PMID:27186404

  8. Imidazole tailored deep eutectic solvents for CO2 capture enhanced by hydrogen bonds.

    Science.gov (United States)

    Cao, Lingdi; Huang, Junhua; Zhang, Xiangping; Zhang, Suojiang; Gao, Jubao; Zeng, Shaojuan

    2015-11-01

    Deep eutectic solvents (DESs) have emerged as promising alternative candidates for CO2 capture in recent years. In this work, several novel DESs were firstly prepared to enhance CO2 absorption. Structural and physical properties of DESs were investigated, as well as their absorption performance of CO2. A distinct depression in the melting point up to 80 K of DESs was observed compared with that of BMIMCl. The observed red shifts of the C2H group in an imidazolium ring and its chemical shifts downfield in NMR spectra are indicative of a hydrogen bond interaction between BMIMCl and MEA. In particular, CO2 uptake in MEA : ILs (4 : 1) at room temperature and atmospheric pressure is up to 21.4 wt%, which is higher than that of 30 wt% MEA (13%). A hydrogen bond related mechanism was proposed in which ILs act as a medium to improve CO2 uptake through hydrogen bonds. Finally, the firstly reported overall heat of CO2 absorption is slightly higher than that of 30 wt% MEA, implying that the hydrogen bonds of DESs contribute to the overall heat of CO2 absorption. This study reveals that the heat of CO2 absorption can be tailored by the proper molar ratio of MEA and ILs. PMID:26435384

  9. Enhanced Predictive Handover for Fast Proxy Mobile IPv6

    Science.gov (United States)

    Jeon, Seil; Kang, Namhi; Kim, Younghan

    Proxy Mobile IPv6 (PMIPv6) has been proposed in order to overcome the limitations of host-based mobility management in IPv6 networks. However, packet losses during doing handover are still a problem. To solve this issue, several schemes have been developed, and can be classified into two approaches: predictive and reactive handover. Both approaches commonly use bi-directional tunnel between mobile access gateways (MAGs). In predictive schemes especially, mobility support for a mobile node (MN) is triggered by simplified link signal strength. Thereafter, the MN sends handover notification to its serving MAG, and is then able to initiate packet forwarding. Therefore, if the MN moves toward an unexpected MAG that does not have any pre-established tunnel with the serving MAG, it may lead to packet losses. In this paper, we define this problem as Early Packet Forwarding (EPF). As a solution, we propose an enhanced PMIPv6 scheme using two-phase tunnel control based on the IEEE 802.21 Media Independent Handover (MIH).

  10. Incorporating IGCC and CaO sorption-enhanced process for power generation with CO2 capture

    International Nuclear Information System (INIS)

    Highlights: ► CaO sorption-enhanced process is incorporated with IGCC for CO2 capture. ► IGCC–CCS is simplified using CaO sorption-enhanced process. ► The electricity efficiency is around 31–33% and CO2 capture efficiency exceeds 95%. ► Parameters such as sorption pressure influence the system performance. -- Abstract: Integrated gasification combined cycle (IGCC) is a power generation technology to convert solid fuels into electricity. IGCC with CCS is regarded as a promising option to mitigate CO2 emission. In this paper, the CaO sorption-enhanced process is incorporated downstream with coal gasification to produce a hydrogen-rich stream for electricity production and CO2 separation. A WGS-absorber substitutes the high- and low-temperature water–gas shift reactors and desulfurization units in conventional IGCC–CCS to produce a hydrogen-rich stream, which is sent onto a gas turbine. CaO is used as the sorbent to enhance hydrogen production and for CO2 capture. Regeneration of CaO is completed via calcination in a regenerator vessel. The IGCC with CaO sorption-enhanced process is modeled and simulated using Aspen Plus software. Two commercial available gasification technologies, Shell and Texaco, are integrated with the sorption-enhanced process. The results showed IGCC with CaO sorption-enhanced process has a satisfactory system performance. Even though the net electricity efficiency is not as high as expected, just around 30–33%, the system has a high CO2 capture efficiency ∼97% and low pollutant emissions. Moreover, compared with conventional IGCC–CCS, the schematic diagram of the IGCC–CCS process is simplified. Parameters that affect the plant performance are analyzed in the sensitive analysis, including WGS-absorber temperature, H2O/CO ratio, pressure, etc. Some challenges to the system are also discussed.

  11. [Sonic Enhanced Ash Agglomeration and Sulfur Capture]. [Quarterly technical progress report, September 27, 1993--January 2, 1994

    Energy Technology Data Exchange (ETDEWEB)

    1993-12-31

    A major concern with the utilization of coal in directly fired gas turbines is the control of particulate emissions and reduction of sulfur dioxide, and alkali vapor from combustion of coal, upstream of the gas turbine. The Sonic Enhanced Ash Agglomeration and Sulfur Capture program focuses upon the application of an MTCI proprietary invention (Patent No. 5,197,399) for simultaneously enhancing sulfur capture and particulate agglomeration of the combustor effluent. This application can be adapted as either a ``hot flue gas cleanup`` subsystem for the current concepts for combustor islands or as an alternative primary pulse combustor island in which slagging, sulfur capture, particulate agglomeration and control, and alkali gettering as well as NO{sub x} control processes become an integral part of the pulse combustion process. The goal of the program is to support the DOE mission in developing coal-fired combustion gas turbines. In particular, the MTCI proprietary process for bimodal ash agglomeration and simultaneous sulfur capture will be evaluated and developed. The technology embodiment of the invention provides for the use of standard grind, moderately beneficiated coal and WEM for firing the gas turbine with efficient sulfur capture and particulate emission control upstream of the turbine. The process also accommodates injection of alkali gettering material if necessary. This is aimed at utilization of relatively inexpensive coal fuels, thus realizing the primary benefit being sought by direct firing of coal in such gas turbine systems.

  12. Fast-track evaluation of a compact chemically enhanced-trickling filter system

    OpenAIRE

    S. A. R. Ahmed

    2007-01-01

    With the more Stringent legislations pertinent to the management of industrial effluents, it deemed necessary to develop an efficient compact, low cost treatment system that complies with applicable laws. Numerous versions of chemically enhanced - biological treatment schemes are commercially established. Chemically enhanced-trickling filter has been perceived as an efficient intervention scheme. This paper presents a fast-track approach for estimation of the minimum total annual treatment co...

  13. PIN diodes for measurement of the gamma dose rate produced by the fast burst reactor operating in the gamma enhancement mode

    International Nuclear Information System (INIS)

    The Fast Burst Reactor (FBR) is operated in the gamma enhancement mode to produce long pulses of gamma radiation for special test requirements. In this particular mode of operation, varying thickness of cadmium and dysprosium loaded polyethylene are used to enhance the gamma radiation environment of the FBR. In principle, the polyethylene thermalizes the fast neutron component of the FBR, the thermal and epithermal neutrons are captured by the cadmium and dysprosium which, in turn, results in a strong capture gamma ray environment. The enhanced gamma environment is used for selected nuclear survivability tests. In addition to the total ionizing dose (measured by thermoluminescent detectors), the gamma dose rate and rate profile is of prime importance. In fact, the peak gamma dose rate is most often the desired quantity. PIN diodes have proven a very useful method for measuring the instantaneous dose rates from the FBR gamma enhanced mode of operation. This presentation describes results and characteristics of these diodes for making such measurements along with calibration methods and long term stability of the diode calibration

  14. A Study of a Modified Histogram Based Fast Enhancement Algorithm (MHBFE

    Directory of Open Access Journals (Sweden)

    Amany A. Kandeel

    2014-02-01

    Full Text Available Image enhancement is one of the most important issues in low-level image processing. The goal of image enhancement is to improve the quality of an image such that enhanced image is better than the original image. Conventional Histogram equalization (HE is one of the most algorithms used in the contrast enhancement of medical images, this due to its simplicity and effectiveness. However, it causes the unnatural look and visual artefacts, where it tends to change the brightness of an images. The Histogram Based Fast Enhancement Algorithm (HBFE tries to enhance the CT head images, where it improves the water-washed effect caused by conventional histogram equalization algorithms with less complexity. It depends on using full gray levels to enhance the soft tissues ignoring other image details. We present a modification of this algorithm to be valid for most CT image types with keeping the degree of simplicity. Experimental results show that The Modified Histogram Based Fast Enhancement Algorithm (MHBFE enhances the results in term of PSNR, AMBE and entropy. We use also the Statistical analysis to ensure the improvement of the proposed modification that can be generalized. ANalysis Of VAriance (ANOVA is used as first to test whether or not all the results have the same average. Then we find the significant improvement of the modification.

  15. FAST

    DEFF Research Database (Denmark)

    Zuidmeer-Jongejan, Laurian; Fernandez-Rivas, Montserrat; Poulsen, Lars K.;

    2012-01-01

    ABSTRACT: The FAST project (Food Allergy Specific Immunotherapy) aims at the development of safe and effective treatment of food allergies, targeting prevalent, persistent and severe allergy to fish and peach. Classical allergen-specific immunotherapy (SIT), using subcutaneous injections with...... aqueous food extracts may be effective but has proven to be accompanied by too many anaphylactic side-effects. FAST aims to develop a safe alternative by replacing food extracts with hypoallergenic recombinant major allergens as the active ingredients of SIT. Both severe fish and peach allergy are caused...... lower their threshold for fish or peach intake, thereby decreasing their anxiety and dependence on rescue medication....

  16. Fast-track surgery-an update on physiological care principles to enhance recovery

    DEFF Research Database (Denmark)

    Kehlet, Henrik

    2011-01-01

    INTRODUCTION: The concept of fast-track surgery (enhanced recovery programs) has been evolved and been documented to be successful by decreasing length of stay, morbidity and convalescence across procedures. FUTURE STRATEGIES: However, there are several possibilities for further improvement of most...

  17. Impact of a low-energy enhancement in the gamma-ray strength function on the radiative neutron-capture

    OpenAIRE

    Larsen, A.C.; Goriely, S.

    2012-01-01

    A low-energy enhancement of the gamma-ray strength function in several light and medium-mass nuclei has been observed recently in 3He-induced reactions. The effect of this enhancement on (n,gamma) cross-sections is investigated for stable and unstable neutron-rich Fe, Mo and Cd isotopes. Our results indicate that the radiative neutron capture cross sections may increase considerably due to the low-energy enhancement when approaching the neutron drip line. This could have non-negligible conseq...

  18. Conceptual study of a compact accelerator-driven neutron source for radioisotope production, boron neutron capture therapy and fast neutron therapy

    CERN Document Server

    Angelone, M; Rollet, S

    2002-01-01

    The feasibility of a compact accelerator-driven device for the generation of neutron spectra suitable for isotope production by neutron capture, boron neutron capture therapy and fast neutron therapy, is analyzed by Monte Carlo simulations. The device is essentially an extension of the activator proposed by Rubbia left bracket CERN/LHC/97-04(EET) right bracket , in which fast neutrons are diffused and moderated within a properly sized lead block. It is shown that by suitable design of the lead block, as well as of additional elements of moderating and shielding materials, one can generate and exploit neutron fluxes with the spectral features required for the above applications. The linear dimensions of the diffusing-moderating device can be limited to about 1 m. A full-scale device for all the above applications would require a fast neutron source of about 10**1**4 s**-**1, which could be produced by a 1 mA, 30 MeV proton beam impinging on a Be target. The concept could be tested at the Frascati Neutron Gener...

  19. Kinetic energy release in CO fragmentation by electron loss and capture collisions of fast B''2''+ ions

    International Nuclear Information System (INIS)

    Ionization and fragmentation of CO molecules have been investigated in charge-changing collisions of B''2''+ ions at v = 1.69 a.u.. Fragment ions from CO were measured by using a momentum 3D imaging technique in coincidence with outgoing projectile charge states. We deduced the kinetic energy release (KER) associated with charge-changing collisions of B''2''+ to B''3''+, B''1''+ and B''0''+. The KER spectra in the fragmentation to C''+ and O''+ ions are found to be different to some extent for these loss and capture collisions. It is concluded that the electron loss collision populates the intact CO molecule to highly excited states of (CO)''2''+''1 more effectively than electron capture collisions, resulting from different effective impact parameters associated with loss and capture collisions.

  20. Measurement of the fast neutron capture cross section of 238U relative to 235U(n,f)

    International Nuclear Information System (INIS)

    The capture cross section of 238U was measured using the activation technique and 235U(n,f) as a reference cross section. Capture events were measured by detection of two prominent γ-transitions in the decay of the 239U daughter nuclide, 239Np, employing a high resolution Ge(Li) detector. The system was calibrated with samples activated in a thermal neutron flux relative to the capture cross section of gold, and with an absolutely calibrated α-emitter, 243Am, which decays to 239Np. Cross section measurements were carried out in the neutron energy range from 30 keV to 3 MeV. Emphasis was on absolute values between 150 keV and 1 MeV where the 238U(n,γ) cross section and its cross section is small. Background from fission products was found to restrict the accuracy of the measured data at energies > 1.5 MeV

  1. MANTRA: An Integral Reactor Physics Experiment to Infer the Neutron Capture Cross Sections of Actinides and Fission Products in Fast and Epithermal Spectra

    Science.gov (United States)

    Youinou, G.; Vondrasek, R.; Veselka, H.; Salvatores, M.; Paul, M.; Pardo, R.; Palmiotti, G.; Palchan, T.; Nusair, O.; Nimmagadda, J.; Nair, C.; Murray, P.; Maddock, T.; Kondrashev, S.; Kondev, F. G.; Jones, W.; Imel, G.; Glass, C.; Fonnesbeck, J.; Berg, J.; Bauder, W.

    2014-05-01

    This paper presents an update of an on-going collaborative INL-ANL-ISU integral reactor physics experiment whose objective is to infer the effective neutron capture cross sections for most of the actinides of importance for reactor physics and fuel cycle studies in both fast and epithermal spectra. Some fission products are also being considered. The principle of the experiment is to irradiate very pure actinide samples in the Advanced Test Reactor at INL and, after a given time, determine the amount of the different transmutation products. The determination of the nuclide densities before and after neutron irradiation together with the neutron fluence will allow inference of effective neutron capture cross-sections in different neutron spectra.

  2. An integrated approach for enhanced protein conjugation and capture with viral nanotemplates and hydrogel microparticle platforms via rapid bioorthogonal reactions.

    Science.gov (United States)

    Jung, Sukwon; Yi, Hyunmin

    2014-07-01

    We demonstrate significantly enhanced protein conjugation and target protein capture capacity by exploiting tobacco mosaic virus (TMV) templates assembled with hydrogel microparticles. Protein conjugation results with a red fluorescent protein R-Phycoerythrin (R-PE) show significantly enhanced protein conjugation capacity of TMV-assembled particles (TMV-particles) compared to planar substrates or hydrogel microparticles. In-depth examination of protein conjugation kinetics via tetrazine (Tz)-trans-cyclooctene (TCO) cycloaddition and strain-promoted alkyne-azide cycloaddition (SPAAC) reaction demonstrates that TMV-particles provide a less hindered environment for protein conjugation. Target protein capture results using an anti-R-PE antibody (R-Ab)-R-PE pair also show substantially improved capture capacity of R-Ab conjugated TMV-particles over R-Ab conjugated hydrogel microparticles. We further demonstrate readily controlled protein and antibody conjugation capacity by simply varying TMV concentrations, which show negligible negative impact of densely assembled TMVs on protein conjugation and capture capacity. Combined, these results illustrate a facile postfabrication protein conjugation approach with TMV templates assembled onto hydrogel microparticles for improved and controlled protein conjugation and sensing platforms. We anticipate that our approach can be readily applied to various protein sensing applications. PMID:24937661

  3. Fasting improves static apnea performance in elite divers without enhanced risk of syncope.

    Science.gov (United States)

    Schagatay, Erika; Lodin-Sundström, Angelica

    2014-01-01

    In competitive apnea divers, the nutritional demands may be essentially different from those of, for example, endurance athletes, where energy resources need to be maximised for successful performance. In competitive apnea, the goal is instead to limit metabolism, as the length of the sustainable apneic period will depend to a great extent on minimising oxygen consumption. Many but not all elite divers fast before performing static apnea in competition. This may increase oxygen consumption as mainly lipid stores are metabolised but could also have beneficial effects on apneic duration. Our aim was to determine the effect of over-night fasting on apnea performance. Six female and seven male divers performed a series of three apneas after eating and fasting, respectively. The series consisted of two 2-min apneas spaced by 3 min rest and, after 5 min rest, one maximal effort apnea. Apneas were performed at supine rest and preceded by normal respiration and maximal inspiration. Mean (± SD) time since eating was 13 h (± 2 h 43 min) for the fasting and 1 h 34 min (± 33 min) for the eating condition (P eating (Peating and ETCO2 was lower in the fasting condition (P eating conditions (P eating (P eating (P < 0.01). The 22% longer apnea duration after fasting with analogous end apnea SaO2 levels suggests that fasting is beneficial for static apnea performance in elite divers, likely via metabolism-limiting mechanisms. The oxygen-conserving effect of the more pronounced diving response and possibly other metabolism-limiting mechanisms related to fasting apparently outweigh the enhanced oxygen consumption caused by lipid metabolism. PMID:24444200

  4. Nanotextured PDMS Substrates for Enhanced Roughness and Aptamer Immobilization for Cancer Cell Capture

    Science.gov (United States)

    Islam, Muhymin; Mahmood, Arif; Bellah, Md.; Kim, Young-Tae; Iqbal, Samir

    2014-03-01

    Detection of circulating tumor cells (CTCs) in the early stages of cancer is requires very sensitive approach. Nanotextured polydimethylsiloxane (PDMS) substrates were fabricated by micro reactive ion etching (Micro-RIE) to have better control on surface morphology and to improve the affinity of PDMS surfaces to capture cancer cells using surface immobilized aptamers. The aptamers were specific to epidermal growth factor receptors (EGFR) present in cell membranes, and overexpressed in tumor cells. We also investigated the effect of nano-scale features on cell capturing by implementing various surfaces of different roughnesses. Three different recipes were used to prepare nanotextured PDMS by micro-RIE using oxygen (O2) and carbon tetrafluoride (CF4). The measured average roughness of three nanotextured PDMS surfaces were found to impact average densities of captured cells. In all cases, nanotextured PDMS facilitated cell capturing possibly due to increased effective surface area of roughened substrates at nanoscale. It was also observed that cell capture efficiency was higher for higher surface roughness. The nanotextured PDMS substrates are thus useful for cancer cytology devices.

  5. Geo-Located Tweets. Enhancing Mobility Maps and Capturing Cross-Border Movement.

    Directory of Open Access Journals (Sweden)

    Justine I Blanford

    Full Text Available Capturing human movement patterns across political borders is difficult and this difficulty highlights the need to investigate alternative data streams. With the advent of smart phones and the ability to attach accurate coordinates to Twitter messages, users leave a geographic digital footprint of their movement when posting tweets. In this study we analyzed 10 months of geo-located tweets for Kenya and were able to capture movement of people at different temporal (daily to periodic and spatial (local, national to international scales. We were also able to capture both long and short distances travelled, highlighting regional connections and cross-border movement between Kenya and the surrounding countries. The findings from this study has broad implications for studying movement patterns and mapping inter/intra-region movement dynamics.

  6. A modified approach to transient stability enhancement with fast valving and braking resistor applications

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Ramnarayan [Indian Institute of Technology, Roorkee, Uttaranchal (India). Department of Electrical Engineering; Bhatti, T.S.; Kothari, D.P. [Indian Institute of Technology, Delhi, New Delhi (India). Centre for Energy Studies

    2006-12-15

    Fast valving and braking resistor are two important members of the family of the discrete supplementary controllers (DISCOS). Both of these are very effective and economic means of transient stability enhancement under extreme contingencies. Being stationed at the similar end of a power system the two schemes carry a very good potential of an effective coordination. Such a coordinated control is helpful not only in obtaining an improved gain in stability, but also in overcoming the limitations and avoiding excessive duty on the part of an individual controller. In this work, a detailed study has been carried out to evaluate the scope and limitations of fast valving and dynamic braking resistor controls in enhancing the transient stability of power systems. Improvements have been suggested over the conventional schemes of control so as to improve their adaptability under different conditions of fault and loading or with different types of generating units. (author)

  7. Enhanced plasma availability of the metabolites of albendazole in fasted adult sheep.

    Science.gov (United States)

    Lifschitz, A; Virkel, G; Mastromarino, M; Lanusse, C

    1997-04-01

    The influence of fasting prior to treatment and of dosing rate on the plasma availability and disposition kinetics of albendazole (ABZ) and its sulphoxide (ABZSO) and sulphone (ABZSO2) metabolites was studied in adult sheep grazing on pasture. A micronized suspension of ABZ was administered orally at either 7.5 mg/kg (group A) or 11.3 mg/kg (group C) to sheep fed ad libitum, and at 7.5 mg/kg to sheep subjected to a 24 h fasting period prior to treatment (group B). Blood samples were taken serially over 96 h after treatment, and the plasma was analysed for ABZ and its metabolites by high-performance liquid chromatography. ABZSO and ABZSO2 were recovered from the plasma. Fasting induced marked modifications in the pharmacokinetic behaviour of the ABZ metabolites in sheep. An extended absorption process, with a delayed peak concentration in the plasma, was observed for both metabolites in the fasted sheep. Significantly higher area under the curve (AUC) and peak plasma concentration (Cmax) values were obtained for both metabolites in the fasted animals compared to those fed ad libitum. Delayed elimination with prolonged detection in plasma was also observed in the fasted sheep. Treatment with ABZ at 7.5 mg/kg in the starved animals resulted in bioequivalence to the administration of the compound at a 50% higher dose rate (11.3 mg/kg) in the fed animals. It is suggested that fasting enhances ABZ dissolution and absorption by delaying its passage down the digestive tract. PMID:9090047

  8. Resonant Enhancement of Neutrinoless Double-Electron Capture in 152Gd

    International Nuclear Information System (INIS)

    In the search for the nuclide with the largest probability for neutrinoless double-electron capture, we have determined the Qεε value between the ground states of 152Gd and 152Sm by Penning-trap mass-ratio measurements. The new Qεε value of 55.70(18) keV results in a half-life of 1026 yr for a 1 eV neutrino mass. With this smallest half-life among known 0νεε transitions, 152Gd is a promising candidate for the search for neutrinoless double-electron capture.

  9. Measurement of the fast neutron capture cross section of /sup 238/U relative to /sup 235/U(n,f)

    Energy Technology Data Exchange (ETDEWEB)

    Fawcett, L.R. Jr.; Poenitz, W.P.; Smith, D.L.

    1979-01-01

    The capture cross section of /sup 238/U was measured using the activation technique and /sup 235/U(n,f) as a reference cross section. Capture events were measured by detection of two prominent ..gamma..-transitions in the decay of the /sup 239/U daughter nuclide, /sup 239/Np, employing a high resolution Ge(Li) detector. The system was calibrated with samples activated in a thermal neutron flux relative to the capture cross section of gold, and with an absolutely calibrated ..cap alpha..-emitter, /sup 243/Am, which decays to /sup 239/Np. Cross section measurements were carried out in the neutron energy range from 30 keV to 3 MeV. Emphasis was on absolute values between 150 keV and 1 MeV where the /sup 238/U(n,..gamma..) cross section and its cross section is small. Background from fission products was found to restrict the accuracy of the measured data at energies > 1.5 MeV.

  10. Meniscal tears of the knee : diagnosis with fast spin-echo MR imaging and role of gadolinium-enhancement

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Kyung Mi; Jee, Won Hee; Choe, Bo Young; Rhim, Soo A.; Lee, Jung Whee; Ku, Young Mi; Yoon, Young Hyun; Choi, Si Young; Choi, Kyu Ho; Shinn, Kyung Sub [Catholic Univ., Seoul (Korea, Republic of). Medical Coll.

    1998-01-01

    The usefulness of fast spin-echo MR imaging for the diagnosis of meniscal tear to the knee is a matter of debate. The purpose of this study was to evaluate the accuracy of diagnosis of meniscal tears by fast spin-echo MR imaging and the role of gadolinium enhancement. In 68 cases of arthroscopically-proven meniscal tears, MR sensitivity to tear was 93% (63/68) for spin-echo alone and 96% (40/41) for combined fast spin-echo and fat-suppressed gadolinium-enhanced T1-weighted MR images. MR sensitivity to medial meniscus tear was 98% (40/41) for fast spin-echo alone and 98% (40/41) for combined fast spin-echo and fat-suppressed gadolinium-enhanced T1-weighted MR images. MR sensitivity to lateral meniscus tear was 85 % (23/27) for fast spin-echo alone and 93% (25/27) for combined fast spin-echo and fat-suppressed gadolinium-enhanced T1-weighted MR images. Fast spin-echo MR imaging with adequate imaging parameters is suitable for the diagnosis of meniscal tears, and additional fat-suppressed gadolinium-enhanced T1-weighted MR imaging may increase diagnostic sensitivity to such tears. (author). 13 refs., 1 tab., 3 figs.

  11. Laser pulse propagation and enhanced energy coupling to fast electrons in dense plasma gradients

    International Nuclear Information System (INIS)

    Laser energy absorption to fast electrons during the interaction of an ultra-intense (1020 W cm−2), picosecond laser pulse with a solid is investigated, experimentally and numerically, as a function of the plasma density scale length at the irradiated surface. It is shown that there is an optimum density gradient for efficient energy coupling to electrons and that this arises due to strong self-focusing and channeling driving energy absorption over an extended length in the preformed plasma. At longer density gradients the laser filaments, resulting in significantly lower overall energy coupling. As the scale length is further increased, a transition to a second laser energy absorption process is observed experimentally via multiple diagnostics. The results demonstrate that it is possible to significantly enhance laser energy absorption and coupling to fast electrons by dynamically controlling the plasma density gradient. (paper)

  12. Enhanced performance of solar cells with optimized surface recombination and efficient photon capturing via anisotropic-etching of black silicon

    Energy Technology Data Exchange (ETDEWEB)

    Chen, H. Y.; Peng, Y., E-mail: gdyuan@semi.ac.cn, E-mail: py@usst.edu.cn; Hong, M.; Zhang, Y. B.; Cai, Bin; Zhu, Y. M. [Shanghai Key Lab of Modern Optical System and Engineering Research Center of Optical Instrument and System, Ministry of Education, University of Shanghai for Science and Technology, Shanghai 200093 (China); Yuan, G. D., E-mail: gdyuan@semi.ac.cn, E-mail: py@usst.edu.cn; Zhang, Y.; Liu, Z. Q.; Wang, J. X.; Li, J. M. [Semiconductor Lighting R and D Center, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China)

    2014-05-12

    We report an enhanced conversion efficiency of femtosecond-laser treated silicon solar cells by surface modification of anisotropic-etching. The etching improves minority carrier lifetime inside modified black silicon area substantially; moreover, after the etching, an inverted pyramids/upright pyramids mixed texture surface is obtained, which shows better photon capturing capability than that of conventional pyramid texture. Combing of these two merits, the reformed solar cells show higher conversion efficiency than that of conventional pyramid textured cells. This work presents a way for fabricating high performance silicon solar cells, which can be easily applied to mass-production.

  13. Passive magnetic separator integrated with microfluidic mixer: Demonstration of enhanced capture efficiency

    DEFF Research Database (Denmark)

    Lund-Olesen, Torsten; Bruus, Henrik; Hansen, Mikkel Fougt

    2006-01-01

    In this paper, we present two results: (1) a new method for quantifying the efficiency of magnetic bead separators by magnetic measurements, and (2) a new idea for designing efficient magnetic bead separators. For microfluidic magnetic separators, a limiting factor for the capture of magnetic beads...... is the steep decrease of the magnetic force on the beads as a function of their distance to the magnetic structures. Our idea is to integrate the magnetic separator with a microfluidic mixer to ensure that all beads are brought close to the magnetic structures. We have fabricated a magnetic separator...

  14. Radiative electron capture

    International Nuclear Information System (INIS)

    Some data are presented for radiative electron capture by fast moving ions. The radiative electron capture spectrum is shown for O8+ in Ag, along with the energy dependence of the capture cross-section. A discrepancy between earlier data, theoretical prediction, and the present data is pointed out. (3 figs) (U.S.)

  15. Geosynchronous magnetic field responses to fast solar wind dynamic pressure enhancements: MHD field model

    Directory of Open Access Journals (Sweden)

    T. R. Sun

    2012-08-01

    Full Text Available We performed global MHD simulations of the geosynchronous magnetic field in response to fast solar wind dynamic pressure (Pd enhancements. Taking three Pd enhancement events in 2000 as examples, we found that the main features of the total field B and the dominant component Bz can be efficiently predicted by the MHD model. The predicted B and Bz varies with local time, with the highest level near noon and a slightly lower level around mid-night. However, it is more challenging to accurately predict the responses of the smaller component at the geosynchronous orbit (i.e., Bx and By. In contrast, the limitations of T01 model in predicting responses to fast Pd enhancements are presented.

  16. Analysis of an effective optical filtering technique to enhance microwave phase shifts based on slow and fast light effects

    DEFF Research Database (Denmark)

    Chen, Yaohui; Öhman, Filip; Xue, Weiqi;

    2008-01-01

    We theoretically analyze and interpret an effective mechanism, which employs optical filtering to enhance the microwave phase shift that can be achieved in semiconductor optical amplifiers based on slow and fast light effects.......We theoretically analyze and interpret an effective mechanism, which employs optical filtering to enhance the microwave phase shift that can be achieved in semiconductor optical amplifiers based on slow and fast light effects....

  17. Summary Report of the Technical Meeting on Inelastic Scattering and Capture Cross-section Data of Major Actinides in the Fast Neutron Region

    International Nuclear Information System (INIS)

    Recently, tight target uncertainties on the capture and inelastic scattering data for major actinides were derived from advanced reactor sensitivity studies. A Technical Meeting on 'Inelastic Scattering and Capture Cross-section Data of Major Actinides in the Fast Neutron Region' was held at IAEA Headquarters, Vienna, Austria to review the status of nuclear data libraries for these cross sections, the status of the experimental results by which these can be tested and to evaluate what advances in nuclear modeling and measurement technique may bring to improve the knowledge of these cross sections. The participants compared recent evaluations with various modeling approaches that have not yet been adopted in data libraries. Several points of interest were found. First, different evaluations may show very similar performance for macroscopic benchmarks. Second, recent modeling improvements from different communities and using different codes tend to converge on the principles in the case of coupled channel calculations. In particular, it was shown that meaningful results require convergence with respect to the number of coupled channels and the use of the dispersive coupled channels potential based with an isospin dependent term to treat neutrons and protons in a coherent manner appears to be uncontested. Also, the issue regarding the use of transmission coefficients from coupled channels calculations in the Hauser Feshbach model was tackled. Recent and ongoing experimental efforts were presented for capture and inelastic scattering on the major actinides. Results from these are likely to become available in a period from 2 to 5 years. A discussion on the representation of the data in EXFOR revealed that care must be taken interpreting the numbers given in the case of inelastic scattering. It has been a long time since capture data were obtained for fissile nuclei and it is exciting to find new efforts are being considered at LANL, CERN and CENBG/IRMM. It was finally

  18. Dust capture and long-lived density enhancements triggered by vortices in 2D protoplanetary disks

    CERN Document Server

    Surville, Clément; Lin, Douglas N C

    2016-01-01

    We study dust capture by vortices and its long-term consequences in global two-fluid inviscid disk simulations using a new polar grid code RoSSBi. We perform the longest integrations so far, several hundred disk orbits, at the highest resolution attainable in global simulations of disks with dust, namely 2048x4096 grid points. This allows to study the dust evolution well beyond vortex dissipation. We vary a wide range of parameters, most notably the dust-to-gas ratio in the initial setup varies in the range $10^{-3}$ to $0.1$. Irrespective of the initial dust-to-gas ratio we find rapid concentration of the dust inside vortices, reaching dust-to-gas ratios of order unity inside the vortex. We present an analytical model that describes very well the dust capture process inside vortices, finding consistent results for all dust-to-gas ratios. A vortex streaming instability develops which causes invariably vortex destruction. After vortex dissipation large-scale dust-rings encompassing a disk annulus form in most ...

  19. Measurement of the generation ratio of 233U and the average radiation capture cross section of 232Th with 232ThO2 irradiated by fast neutrons

    International Nuclear Information System (INIS)

    Background: Thorium-Uranium cycle plays an important role in the future's power production technology. Nuclear data involved are urgently needed for engineering design and other purposes since there are obvious differences between the existing evaluated data. Macroscopic neutron integral experiment can be used as a good tool to survey the confusion. Purpose: Macroscopic neutron integral experiment based on radioactive method was carried out to measure the generation ratio of 233U nuclide and the average radiation capture cross section of 232Th while a ThO2 sample was irradiated by fast neutrons leakage from a fast critical facility. We expect that these data can be used as a reference for the research of Th-U cycle. Methods: Radiation capture reactions of 232Th nuclides occur when the nuclides are irradiated by neutrons. 233U nuclides will be generated after two cascade decays by emitting beta rays from the activation products, which are 233Th nuclides. The ThO2 sample was prepared as a slice of 20 mm×10 mm from 0.743 36-g ThO2 powders of 99.9% enriched. The neutron flux was measured by activation method which was 4.07x109 cm-2·s-1 at the sample's irradiation position while the facility worked at the power level of 180 watts. The leakage neutrons' energy distribution was calculated by MC method and it is very close to the fission spectrum with the averaged energy of 1.42 MeV. After irradiation and then a period of cooling time the gamma rays emitted from the sample were measured by an HPGe spectrometer which had been pre-calibrated. From these data the activity of 233Pa was calculated and then the generation ratio of 233U and the average radiation capture cross section of 232Th were calculated. The measured average radiation capture cross section was compared with the cross sections calculated based on the ENDFB-VH.1, CENDL-3.1, JENDL-4.0, BROND2.2 databases. Results: The measured generation ratio of 233U was 4.01×10-12 with an uncertainty of 6

  20. Fast Ignition Thermonuclear Fusion: Enhancement of the Pellet Gain by the Colossal-Magnetic-Field Shells

    Science.gov (United States)

    Stefan, V. Alexander

    2013-10-01

    The fast ignition fusion pellet gain can be enhanced by a laser generated B-field shell. The B-field shell, (similar to Earth's B-field, but with the alternating B-poles), follows the pellet compression in a frozen-in B-field regime. A properly designed laser-pellet coupling can lead to the generation of a B-field shell, (up to 100 MG), which inhibits electron thermal transport and confines the alpha-particles. In principle, a pellet gain of few-100s can be achieved in this manner. Supported in part by Nikola Tesla Labs, Stefan University, 1010 Pearl, La Jolla, CA 92038-1007.

  1. Enhanced Multiple Routing Configurations for Fast IP Network Recovery from Multiple Failures

    Directory of Open Access Journals (Sweden)

    T. Anji Kumar

    2011-10-01

    Full Text Available Now a days, Internet plays a major role in our day to day activities e.g., for online transactions, online shopping, and other network related applications. Internet suffers from slow convergence of routing protocols after a network failure which becomes a growing problem. Multiple Routing Configurations [MRC] recovers network from single node/link failures, but does not support network from multiple node/link failures. In this paper, we propose Enhanced MRC [EMRC], to support multiple node/link failures during data transmission in IP networks without frequent global re-convergence. By recovering these failures, data transmission in network will become fast.

  2. Enhanced passive safety features against ATWS of fast breeder reactors with capabilities of MA incineration

    Energy Technology Data Exchange (ETDEWEB)

    Ninokata, Hisashi; Sawada, Tetsuo; Sato, Manabu [Tokyo Institute of Technology (Japan)] [and others

    1997-12-01

    The paper gives an outline of the general and simple reactivity correlation method to identify the region of the major design parameters that assures power stabilization and passive shutdown of sodium-cooled large fast reactors under ATWS conditions. Based on the model developed, general design guidelines are shown that enhance passive capabilities being aimed at preventing sodium boiling and fuel failures in the events of ULOF and UTOP. Discussions extend to the influences of minor actinides loading in the core onto the passive safety features. 6 refs., 1 fig., 1 tab.

  3. Comparison between fast contrast-enhanced MR angiography and DSA in diagnosing spinal cord vascular malformations

    International Nuclear Information System (INIS)

    Objective: To evaluate the diagnostic and clinical value of fast contrast-enhanced MR angiography (CE-MRA) with elliptic centric phase-encoding in spinal cord vascular malformations. Methods Fast three-dimensional contrast-enhanced MR angiography with elliptic centric phase-encoding and superconducting 1.5T system was applied prospectively in twenty-five consecutive patients with clinically suspected of spinal cord vascular malformations. All cases were performed with selective spinal digital subtraction angiography, including 18 cases treated by surgery and 2 of them with embolization before surgery, MR angiography follow up were undertaken in ten patients after surgery. Comparing fast contrast-enhanced MR angiography with DSA in diagnosing spinal cord vascular malformations included the origin of feeding artery, the feeding artery, the fistula or the nidus, the draining vein, and the vessel image quality based on the gold standard of selective spinal digital subtraction angiography. Results: Surgically proven diseases included spinal arteriovenous malformations(3 cases), spinal cord perimedullary arteriovenous fistulas (5 cases), spinal dural arteriovenous fistulas (8 cases), paravertebral arteriovenous fistulas (1 case), and spontaneous spinal epidural hematomas (2 eases). Comparing with DSA, the accuracy of MR angiography in diagnosing spinal cord vascular malformations; and detecting the origin of the feeding artery, the feeding artery, the shunt or the nidus and the draining vein were 93.8%, 92%, 96.2%, 100% and 100%, respectively. Overall the degree vascular enhencement were judged to be similar(P>0.05), but the vessel continuity of MRA was inferior to DSA (P<0.05). However, 9 cases of MRA showed no abnormal vascular malformation coinciding with those of surgery. Posttreatment MR angiography did not depict any abnormal vessels again. Conclusions: Fast three-dimensional contrast-enhanced MR angiography with elliptic centric phase-encoding may provide

  4. Enhanced Multiple Routing Configurations For Fast IP Network Recovery From Multiple Failures

    Directory of Open Access Journals (Sweden)

    T Anji Kumar & Dr MHM Krishna Prasad

    2011-11-01

    Full Text Available Now a days, Internet plays a major role in our day to day activities e.g., for online transactions,online shopping, and other network related applications. Internet suffers from slow convergenceof routing protocols after a network failure which becomes a growing problem. Multiple RoutingConfigurations [MRC] recovers network from single node/link failures, but does not supportnetwork from multiple node/link failures. In this paper, we propose Enhanced MRC [EMRC], tosupport multiple node/link failures during data transmission in IP networks without frequent globalre-convergence. By recovering these failures, data transmission in network will become fast.

  5. Ultra-fast low-angle rapid acquisition and relaxation enhancement (UFLARE) in patients with epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Eriksson, S.H.; Symms, M.R.; Woermann, F.G.; Kendall, B.; Stevens, J.M. [National Society for Epilepsy and Epilepsy Research Group, Chalfont St Peter, Bucks, (United Kingdom); Stepney, A.; Barker, G.J. [Dept. of Clinical Neurology, Univ. College London (United Kingdom); Niendorf, T. [GE Medical Systems, Cardiac- and Neuro-optimized, Leipzig (Germany)

    2001-12-01

    MRI is an important diagnostic tool in patients with epilepsy, but patient motion during long scans may result in image artefacts. We studied the utility of an ultra-fast MR sequence in patients with epilepsy. Ultra-fast low-angle rapid acquisition and relaxation enhancement (UFLARE) images were acquired for 100 consecutive patients and nine control subjects. Scans were compared with routine T2-weighted spin echo images for signal-to-noise ratio, contrast, and conspicuity, followed by a blind review of lesion detectability. UFLARE scans were also acquired for 15 patients who moved during conventional scans. All UFLARE scans had lower signal-to-noise ratios and lower contrast than the T2-weighted images. Compared with T1- and T2-weighted, PD and FLAIR images, 86% of hippocampal sclerosis (HS), 92% of large but only 24% of small white-matter lesions were detected on the blind review of the UFLARE images. Reduced motion artefacts were seen on the UFLARE images in all 15 patients who moved during the conventional scans, and in three patients UFLARE was the only sequence we were able to obtain. Despite the lower lesion detectability for smaller lesions, the use of an ultra-fast MRI sequence such as UFLARE may be very useful in patients who are not able to co-operate during conventional MRI examinations, if a general anaesthetic is to be avoided. (orig.)

  6. Ultra-fast low-angle rapid acquisition and relaxation enhancement (UFLARE) in patients with epilepsy

    International Nuclear Information System (INIS)

    MRI is an important diagnostic tool in patients with epilepsy, but patient motion during long scans may result in image artefacts. We studied the utility of an ultra-fast MR sequence in patients with epilepsy. Ultra-fast low-angle rapid acquisition and relaxation enhancement (UFLARE) images were acquired for 100 consecutive patients and nine control subjects. Scans were compared with routine T2-weighted spin echo images for signal-to-noise ratio, contrast, and conspicuity, followed by a blind review of lesion detectability. UFLARE scans were also acquired for 15 patients who moved during conventional scans. All UFLARE scans had lower signal-to-noise ratios and lower contrast than the T2-weighted images. Compared with T1- and T2-weighted, PD and FLAIR images, 86% of hippocampal sclerosis (HS), 92% of large but only 24% of small white-matter lesions were detected on the blind review of the UFLARE images. Reduced motion artefacts were seen on the UFLARE images in all 15 patients who moved during the conventional scans, and in three patients UFLARE was the only sequence we were able to obtain. Despite the lower lesion detectability for smaller lesions, the use of an ultra-fast MRI sequence such as UFLARE may be very useful in patients who are not able to co-operate during conventional MRI examinations, if a general anaesthetic is to be avoided. (orig.)

  7. ESS-FH: Enhanced Security Scheme for Fast Handover in Hierarchical Mobile IPv6

    Science.gov (United States)

    You, Ilsun; Lee, Jong-Hyouk; Sakurai, Kouichi; Hori, Yoshiaki

    Fast Handover for Hierarchical Mobile IPv6 (F-HMIPv6) that combines advantages of Fast Handover for Mobile IPv6 (FMIPv6) and Hierarchical Mobile IPv6 (HMIPv6) achieves the superior performance in terms of handover latency and signaling overhead compared with previously developed mobility protocols. However, without being secured, F-HMIPv6 is vulnerable to various security threats. In 2007, Kang and Park proposed a security scheme, which is seamlessly integrated into F-HMIPv6. In this paper, we reveal that Kang-Park's scheme cannot defend against the Denial of Service (DoS) and redirect attacks while largely relying on the group key. Then, we propose an Enhanced Security Scheme for F-HMIPv6 (ESS-FH) that achieves the strong key exchange and the key independence as well as addresses the weaknesses of Kang-Park's scheme. More importantly, it enables fast handover between different MAP domains. The proposed scheme is formally verified based on BAN-logic, and its handover latency is analyzed and compared with that of Kang-Park's scheme.

  8. Enhancement of the number of fast electrons generated in a laser inverse cone interaction

    International Nuclear Information System (INIS)

    Enhancement of the energy-conversion efficiency from laser to target electrons is demonstrated by two-dimensional particle-in-cell simulations in a laser-inverse cone interaction. When an intense short-pulse laser illuminates the inverse cone target, the electrons at the cone end are accelerated by the ponderomotive force. Then these electrons are guided and confined to transport along the inverse cone walls by the induced electromagnetic fields. A device consisting of inverse hollow-cone and multihole array plasma is proposed in order to increase the energy-conversion efficiency from laser to electrons. Particle-in-cell simulations present that the multiholes transpiercing the cone end help to enhance the number of fast electrons and the maximum electron energy significantly. (authors)

  9. Enhancement of the Number of Fast Electrons Generated in a Laser Inverse Cone Interaction

    International Nuclear Information System (INIS)

    Enhancement of the energy-conversion efficiency from laser to target electrons is demonstrated by two-dimensional particle-in-cell simulations in a laser-inverse cone interaction. When an intense short-pulse laser illuminates the inverse cone target, the electrons at the cone end are accelerated by the ponderomotive force. Then these electrons are guided and confined to transport along the inverse cone walls by the induced electromagnetic fields. A device consisting of inverse hollow-cone and multihole array plasma is proposed in order to increase the energy-conversion efficiency from laser to electrons. Particle-in-cell simulations present that the multiholes transpiercing the cone end help to enhance the number of fast electrons and the maximum electron energy significantly. (physics of gases, plasmas, and electric discharges)

  10. Contrast-enhanced dynamic MR imaging of parasellar tumor using fast spin-echo sequence

    International Nuclear Information System (INIS)

    We have applied a new dynamic MRI technique that uses a fast spin-echo sequence to parasellar tumors. This sequence has less susceptible effect and better spatial resolution than a gradient echo sequence, providing faster images than a short spin-echo sequence does. Image was obtained in the coronal or sagittal plane using a 1.5T clinical MRI system, and then, dynamic MR images were acquired every 10 to 20 sec after administration of Gd-DTPA (0.1 mmol/kg). The subjects were 12 patients (5 microadenomas, 5 macroadenomas and 2 Rathke's cleft cysts) and 5 normal volunteers. As for volunteers, the cavernous sinus, pituitary stalk and posterior pituitary gland were contrasted on the first image, followed by visualization of the proximal portion adjacent to the junction of the infundibulum and the anterior pituitary gland, and finally by contrasting the distal portion of the anterior pituitary gland. There was a difference with respect to tumor contrast between microadenomas and macroadenomas. In the case of the macroadenomas, the tumor was contrasted at the same time as, or faster than the anterior pituitary gland, while with the microadenomas the tumor was enhanced later than the anterior pituitary gland. No enhancement with contrast medium was seen in Rathke's cleft cysts. In addition, it was possible to differentiate a recurrent tumor from a piece of muscle placed at surgery since the images obtained by the fast spin-echo sequence were clearer than those obtained by gradient echo sequence. (author)

  11. Energy and charge state dependences of transfer ionization to single capture ratio for fast multiply charged ions on helium

    Science.gov (United States)

    Unal, Ridvan

    The charge state and energy dependences of Transfer Ionization (TI) and Single Capture (SC) processes in collisions of multiply charged ions with He from intermediate to high velocities are investigated using coincident recoil ion momentum spectroscopy. The collision chamber is commissioned on the 15-degree port of a switching magnet, which allows the delivery of a beam with very little impurity. The target was provided from a supersonic He jet with a two-stage collimation. The two-stage, geometrically cooled, supersonic He jet has significantly reduced background contribution to the spectrum compared to a single stage He jet. In the case of a differentially pumped gas cell complex calculations based on assumptions for the correction due to the collisions with the contaminant beam led to corrections, which were up to 50%. The new setup allows one to make a direct separation of contaminant processes in the experimental data using the longitudinal momentum spectra. Furthermore, this correction is much smaller (about 8.8%) yielding better overall precision. The collision systems reported here are 1 MeV/u O(4--8)+ , 0.5--2.5 MeV/u F(4--9)+, 2.0 MeV/u Ti 15,17,18+, 1.6--1.75 MeV/u Cu18,20+ and 0.25--0.5 MeV/u I(15--25)+ ions interacting with helium. We have determined the sTIsSC ratio for high velocity highly charged ions on He at velocities in the range of 6 to 10 au and observed that the ratio is monotonically decreasing with velocity. Furthermore, we see a ratio that follows a q2 dependence up to approximately q = 9. Above q = 9 the experimental values exceed the q2 dependence prediction due to antiscreening. C. D. Lin and H. C. Tseng have performed coupled channel calculations for the energy dependence of TI and SC for F9+ + He and find values slightly higher than our measured values, but with approximately the same energy dependence. The new data, Si, Ti and Cu, go up only to q = 20 and show a smooth monotonically increasing TI/SC ratio. The TI/SC ratio for I (15

  12. Signal enhancement of lead and arsenic in soil using laser ablation combined with fast electric discharge

    Energy Technology Data Exchange (ETDEWEB)

    Kexue, L.I. [Institute of Information Optics, Zhejiang Normal University, Jinhua, 321004 (China); Zhou Weidong, E-mail: wdzhou@zjnu.c [Institute of Information Optics, Zhejiang Normal University, Jinhua, 321004 (China); Shen Qinmei; Shao Jie; Qian Huiguo [Institute of Information Optics, Zhejiang Normal University, Jinhua, 321004 (China)

    2010-05-15

    In comparison to the traditional single pulse laser induced breakdown spectroscopy (SP-LIBS), a significant enhancement of atomic emission of lead and arsenic from laser plasma of soil has been demonstrated by the use of a laser ablation and fast pulse discharge plasma spectroscopy technique (LA-FPDPS). In this technique, a specifically designed high voltage and rapid discharge circuit was used to reheat the laser plasma and to enhance the plasma emission. A rapid and time damped alternating discharge current was observed with a short oscillating period {approx} 0.6 {mu}s and sustained for about 6 {mu}s. The peak intensities of Pb (283.31 nm) and As (286.04 nm) lines from soil plasma emission were greatly enhanced when compare to the traditional single pulse (SP) LIBS system. In addition, the precision of measurements in terms of the relative standard deviation (RSD) and the signal to noise (S/N) ratios were also improved. Scanning electron microscopy (SEM) images of the laser ablation regions indicated that the plasma reheating by the discharge spark was presumably the main mechanism for observed signal enhancement in the LA-FPDPS technique.

  13. Chemical Looping Gasification for Hydrogen Enhanced Syngas Production with In-Situ CO2 Capture

    Energy Technology Data Exchange (ETDEWEB)

    Kathe, Mandar [Ohio State University, Columbus, OH (United States); Xu, Dikai [Ohio State University, Columbus, OH (United States); Hsieh, Tien-Lin [Ohio State University, Columbus, OH (United States); Simpson, James [Ohio State University, Columbus, OH (United States); Statnick, Robert [Ohio State University, Columbus, OH (United States); Tong, Andrew [Ohio State University, Columbus, OH (United States); Fan, Liang-Shih [Ohio State University, Columbus, OH (United States)

    2014-12-31

    This document is the final report for the project titled “Chemical Looping Gasification for Hydrogen Enhanced Syngas Production with In-Situ CO2 Capture” under award number FE0012136 for the performance period 10/01/2013 to 12/31/2014.This project investigates the novel Ohio State chemical looping gasification technology for high efficiency, cost efficiency coal gasification for IGCC and methanol production application. The project developed an optimized oxygen carrier composition, demonstrated the feasibility of the concept and completed cold-flow model studies. WorleyParsons completed a techno-economic analysis which showed that for a coal only feed with carbon capture, the OSU CLG technology reduced the methanol required selling price by 21%, lowered the capital costs by 28%, increased coal consumption efficiency by 14%. Further, using the Ohio State Chemical Looping Gasification technology resulted in a methanol required selling price which was lower than the reference non-capture case.

  14. Enhanced Carbon Dioxide Capture from Landfill Gas Using Bifunctionalized Benzimidazole-Linked Polymers.

    Science.gov (United States)

    Islamoglu, Timur; Behera, Swayamprabha; Kahveci, Zafer; Tessema, Tsemre-Dingel; Jena, Puru; El-Kaderi, Hani M

    2016-06-15

    Tuning the binding affinity of small gases and their selective uptake by porous adsorbents are vital for effective CO2 removal from gas mixtures for environmental protection and fuel upgrading. In this study, an amine-functionalized benzimidazole-linked polymer (BILP-6-NH2) was synthesized by a combination of pre- and postsynthetic modification techniques in two steps. Presynthetic incorporation of nitro groups resulted in stoichiometric functionalization (1 nitro/phenyl) in addition to noninvasive functionalization, where more than 80% of the surface area maintained compared to BILP-6. Experimental studies presented enhanced CO2 uptake and CO2/CH4 selectivity in BILP-6-NH2 compared to BILP-6, which are governed by the synergetic effect of benzimidazole and amine moieties. DFT calculations were used to understand the interaction modes of CO2 with BILP-6-NH2 and confirmed the efficacy of amine groups. Encouraged by the enhanced uptake and selectivity in BILP-6-NH2, we have evaluated its performance in landfill gas separation under vacuum swing adsorption (VSA) settings, which resulted in very promising working capacity and sorbent selection parameters outperforming most of the best solid adsorbent in the literature. PMID:27228220

  15. A Novel Feature Extraction Approach Using Window Function Capturing and QPSO-SVM for Enhancing Electronic Nose Performance.

    Science.gov (United States)

    Guo, Xiuzhen; Peng, Chao; Zhang, Songlin; Yan, Jia; Duan, Shukai; Wang, Lidan; Jia, Pengfei; Tian, Fengchun

    2015-01-01

    In this paper, a novel feature extraction approach which can be referred to as moving window function capturing (MWFC) has been proposed to analyze signals of an electronic nose (E-nose) used for detecting types of infectious pathogens in rat wounds. Meanwhile, a quantum-behaved particle swarm optimization (QPSO) algorithm is implemented in conjunction with support vector machine (SVM) for realizing a synchronization optimization of the sensor array and SVM model parameters. The results prove the efficacy of the proposed method for E-nose feature extraction, which can lead to a higher classification accuracy rate compared to other established techniques. Meanwhile it is interesting to note that different classification results can be obtained by changing the types, widths or positions of windows. By selecting the optimum window function for the sensor response, the performance of an E-nose can be enhanced. PMID:26131672

  16. A Novel Feature Extraction Approach Using Window Function Capturing and QPSO-SVM for Enhancing Electronic Nose Performance

    Directory of Open Access Journals (Sweden)

    Xiuzhen Guo

    2015-06-01

    Full Text Available In this paper, a novel feature extraction approach which can be referred to as moving window function capturing (MWFC has been proposed to analyze signals of an electronic nose (E-nose used for detecting types of infectious pathogens in rat wounds. Meanwhile, a quantum-behaved particle swarm optimization (QPSO algorithm is implemented in conjunction with support vector machine (SVM for realizing a synchronization optimization of the sensor array and SVM model parameters. The results prove the efficacy of the proposed method for E-nose feature extraction, which can lead to a higher classification accuracy rate compared to other established techniques. Meanwhile it is interesting to note that different classification results can be obtained by changing the types, widths or positions of windows. By selecting the optimum window function for the sensor response, the performance of an E-nose can be enhanced.

  17. Sublingual fast dissolving niosomal films for enhanced bioavailability and prolonged effect of metoprolol tartrate

    Directory of Open Access Journals (Sweden)

    Allam A

    2016-08-01

    Full Text Available Ayat Allam, Gihan Fetih Department of Pharmaceutics, Faculty of Pharmacy, Assiut University, Assiut, Egypt Abstract: The aim of the present work was to prepare and evaluate sublingual fast dissolving films containing metoprolol tartrate-loaded niosomes. Niosomes were utilized to allow for prolonged release of the drug, whereas the films were used to increase the drug’s bioavailability via the sublingual route. Niosomes were prepared using span 60 and cholesterol at different drug to surfactant ratios. The niosomes were characterized for size, zeta-potential, and entrapment efficiency. The selected niosomal formulation was incorporated into polymeric films using hydroxypropyl methyl cellulose E15 and methyl cellulose as film-forming polymers and Avicel as superdisintegrant. The physical characteristics (appearance, texture, pH, uniformity of weight and thickness, disintegration time, and palatability of the prepared films were studied, in addition to evaluating the in vitro drug release, stability, and in vivo pharmacokinetics in rabbits. The release of the drug from the medicated film was fast (99.9% of the drug was released within 30 minutes, while the drug loaded into the niosomes, either incorporated into the film or not, showed only 22.85% drug release within the same time. The selected sublingual film showed significantly higher rate of drug absorption and higher drug plasma levels compared with that of commercial oral tablet. The plasma levels remained detectable for 24 hours following sublingual administration, compared with only 12 hours after administration of the oral tablet. In addition, the absolute bioavailability of the drug (ie, relative to intravenous administration following sublingual administration was found to be significantly higher (91.06%±13.28%, as compared with that after oral tablet administration (39.37%±11.4%. These results indicate that the fast dissolving niosomal film could be a promising delivery system to

  18. Fast neutron capture cross sections of 169Tm, 191Ir, 193Ir, and 175Lu for 3 less than or equal to E/sub n/ less than or equal to 2000 keV

    International Nuclear Information System (INIS)

    Fast neutron capture cross sections of 169Tm, 191Ir, 193Ir, and 175Lu, and the 6Li(n,α)3H cross sections to which they are normalized are presented in tabular form for neutron energies between 3 and 2000 keV

  19. A Surface-Enhanced Raman Scattering Sensor Integrated with Battery-Controlled Fluidic Device for Capture and Detection of Trace Small Molecules

    OpenAIRE

    Qitao Zhou; Guowen Meng; Peng Zheng; Scott Cushing; Nianqiang Wu; Qing Huang; Chuhong Zhu; Zhuo Zhang; Zhiwei Wang

    2015-01-01

    For surface-enhanced Raman scattering (SERS) sensors, one of the important issues is the development of substrates not only with high SERS-activity but also with strong ability to capture analytes. However, it is difficult to achieve the two goals simultaneously especially when detecting small molecules. Herein a compact battery-controlled nanostructure-assembled SERS system has been demonstrated for capture and detection of trace small molecule pollutants in water. In this SERS fluidic syste...

  20. Fast esterification of spent grain for enhanced heavy metal ions adsorption.

    Science.gov (United States)

    Li, Qingzhu; Chai, Liyuan; Wang, Qingwei; Yang, Zhihui; Yan, Huxiang; Wang, Yunyan

    2010-05-01

    This work describes a novel method for fast esterification of spent grain to enhance its cationic adsorption capacity. The esterification of spent grain with citric acid was achieved by using sodium hypophosphite monohydrate (NaH(2)PO(2).H(2)O) as a catalyst in N,N-dimethylformamide (DMF). Fourier transform infrared (FTIR) spectroscopic analysis revealed the formation of ester groups after esterification, demonstrating that spent grain was successfully esterified with citric acid. The adsorption capacity of esterified spent grain (ESG) for each metal ion was greatly improved as compared with that of raw spent grain (RSG). Typically, Pb(2+) adsorption capacity increased from 125.84mg g(-1) of RSG to 293.30mg g(-1) of ESG. This increase can be attributed to both the formation of ester linkage and the grafting of carboxyl groups on spent grain. The results suggest that a fast process for esterification of spent grain has been realized and ESG has strong ability to adsorb heavy metal ions. PMID:20110169

  1. MUSIC. a fast T2* - sensitive MRI technique with enhanced volume coverage

    International Nuclear Information System (INIS)

    A fast imaging method based on gradient-recalled echoes and echo time inter-leaved multi-slice excitation is presented. This method maintains the sensitivity of T2* by using a long echo time of at least 35 milliseconds. Bipolar gradients are used to shift the gradient echoes in order to ensure constant TE for each slab and prevent ghost-artefacts within the images caused by spin- or stimulated echoes. This method enhances the total imaging time of a conventional multi-slice gradient echo technique, while maintaining the high volume coverage. Thus, stimulated human cortical activation maps can be detected on standard clinical MR instruments at several planes within measuring times of a few seconds. The efficiency of the technique is demonstrated in the detection of temporary changes in T2* in functional MRI experiments of the human visual cortex at a magnetic field strength of 2 tesla. (author). 18 refs., 6 figs

  2. Fast Hue-Preserving Histogram Equalization Methods For Color Image Contrast Enhancement

    Directory of Open Access Journals (Sweden)

    David Menotti

    2012-11-01

    Full Text Available In this work, we formalize a generic fast hue-preserving histogram equalization method based on the RGBcolor space for image contrast enhancement and two versions of that generic process. The first methodestimates a RGB 3D histogram to be equalized using R-red, G-green, and B-blue 1D histograms, while thesecond method employs RG, RB, and GB 2D histograms. The histogram equalization is performed usingshift hue-preserving transformations, avoiding unrealistic colors. Our methods have linear time and spacecomplexities with respect to the size of the image and do not need to apply conversions from a color spaceto another in order to perform the image enhancement. Such design complies with real-time applicationsrequirements. An objective assessment comparing our methods and others is performed using a contrastmeasure and a color image quality measure, where the quality is established as a weighting of thenaturalness and colorfulness indexes. We analyze 300 images from the dataset of the University ofBerkeley. Experiments show that the value of the image contrast produced by our methods is in average50% greater than the original image value, keeping the quality of the produced images close to the originalone.

  3. Carbon Capture and Sequestration (via Enhanced Oil Recovery) from a Hydrogen Production Facility in an Oil Refinery

    Energy Technology Data Exchange (ETDEWEB)

    Stewart Mehlman

    2010-06-16

    The project proposed a commercial demonstration of advanced technologies that would capture and sequester CO2 emissions from an existing hydrogen production facility in an oil refinery into underground formations in combination with Enhanced Oil Recovery (EOR). The project is led by Praxair, Inc., with other project participants: BP Products North America Inc., Denbury Onshore, LLC (Denbury), and Gulf Coast Carbon Center (GCCC) at the Bureau of Economic Geology of The University of Texas at Austin. The project is located at the BP Refinery at Texas City, Texas. Praxair owns and operates a large hydrogen production facility within the refinery. As part of the project, Praxair would construct a CO2 capture and compression facility. The project aimed at demonstrating a novel vacuum pressure swing adsorption (VPSA) based technology to remove CO2 from the Steam Methane Reformers (SMR) process gas. The captured CO2 would be purified using refrigerated partial condensation separation (i.e., cold box). Denbury would purchase the CO2 from the project and inject the CO2 as part of its independent commercial EOR projects. The Gulf Coast Carbon Center at the Bureau of Economic Geology, a unit of University of Texas at Austin, would manage the research monitoring, verification and accounting (MVA) project for the sequestered CO2, in conjunction with Denbury. The sequestration and associated MVA activities would be carried out in the Hastings field at Brazoria County, TX. The project would exceed DOE’s target of capturing one million tons of CO2 per year (MTPY) by 2015. Phase 1 of the project (Project Definition) is being completed. The key objective of Phase 1 is to define the project in sufficient detail to enable an economic decision with regard to proceeding with Phase 2. This topical report summarizes the administrative, programmatic and technical accomplishments completed in Phase 1 of the project. It describes the work relative to project technical and design activities

  4. Capturing Thoughts, Capturing Minds?

    DEFF Research Database (Denmark)

    Nielsen, Janni

    2004-01-01

    Think Aloud is cost effective, promises access to the user's mind and is the applied usability technique. But 'keep talking' is difficult, besides, the multimodal interface is visual not verbal. Eye-tracking seems to get around the verbalisation problem. It captures the visual focus of attention....... However, it is expensive, obtrusive and produces huge amount of data. Besides, eye-tracking do not give access to user's mind. Capturing interface/cursor tracking may be cost effective. It is easy to install, data collection is automatic and unobtrusive and replaying the captured recording to the user and...

  5. X-ray photon correlation spectroscopy using a fast pixel array detector with a grid mask resolution enhancer

    International Nuclear Information System (INIS)

    The performance of a fast pixel array detector with a grid mask resolution enhancer has been demonstrated for X-ray photon correlation spectroscopy experiments. The performance of a fast pixel array detector with a grid mask resolution enhancer has been demonstrated for X-ray photon correlation spectroscopy (XPCS) measurements to investigate fast dynamics on a microscopic scale. A detecting system, in which each pixel of a single-photon-counting pixel array detector, PILATUS, is covered by grid mask apertures, was constructed for XPCS measurements of silica nanoparticles in polymer melts. The experimental results are confirmed to be consistent by comparison with other independent experiments. By applying this method, XPCS measurements can be carried out by customizing the hole size of the grid mask to suit the experimental conditions, such as beam size, detector size and sample-to-detector distance

  6. Evidence for field enhanced electron capture by EL2 centers in semi-insulating GaAs and the effect on GaAs radiation detectors

    International Nuclear Information System (INIS)

    The performance of Schottky contact semiconductor radiation detectors fabricated from semi-insulating GaAs is highly sensitive to charged impurities and defects in the material. The observed behavior of semi-insulating GaAs Schottky barrier alpha particle detectors does not match well with models that treat the semi-insulating material as either perfectly intrinsic or as material with deep donors (EL2) of constant capture cross section compensated with shallow acceptors. We propose an explanation for the discrepancy based on enhanced capture of electrons by EL2 centers at high electric fields and the resulting formation of a quasineutral region in the GaAs. Presented is a simple model including field enhanced electron capture which shows good agreement with experimental alpha particle pulse height measurements

  7. A fast color image enhancement algorithm based on Max Intensity Channel.

    Science.gov (United States)

    Sun, Wei; Han, Long; Guo, Baolong; Jia, Wenyan; Sun, Mingui

    2014-03-30

    In this paper, we extend image enhancement techniques based on the retinex theory imitating human visual perception of scenes containing high illumination variations. This extension achieves simultaneous dynamic range modification, color consistency, and lightness rendition without multi-scale Gaussian filtering which has a certain halo effect. The reflection component is analyzed based on the illumination and reflection imaging model. A new prior named Max Intensity Channel (MIC) is implemented assuming that the reflections of some points in the scene are very high in at least one color channel. Using this prior, the illumination of the scene is obtained directly by performing a gray-scale closing operation and a fast cross-bilateral filtering on the MIC of the input color image. Consequently, the reflection component of each RGB color channel can be determined from the illumination and reflection imaging model. The proposed algorithm estimates the illumination component which is relatively smooth and maintains the edge details in different regions. A satisfactory color rendition is achieved for a class of images that do not satisfy the gray-world assumption implicit to the theoretical foundation of the retinex. Experiments are carried out to compare the new method with several spatial and transform domain methods. Our results indicate that the new method is superior in enhancement applications, improves computation speed, and performs well for images with high illumination variations than other methods. Further comparisons of images from National Aeronautics and Space Administration and a wearable camera eButton have shown a high performance of the new method with better color restoration and preservation of image details. PMID:25110395

  8. Enhancement of the inherent self-protection of the fast sodium reactor cores with oxide fuel

    International Nuclear Information System (INIS)

    With the development and research into the generation IV fast sodium reactors, great attention is paid to the enhancement of the core inherent self-protection characteristics. One of the problems dealt here is connected with the reduction of the reactivity margin so that the control rods running should not result in the core overheating and melting. In this paper we consider the possibilities of improving the core of BN-1200 with oxide fuel by a known method of introducing an axial fertile layer into the core. But unlike earlier studies this paper looks at the possibility of using such a layer not only for improving breeding, but also for reducing sodium void reactivity effect (SVRE). This proposed improvement of the BN-1200 core does not solve the problem of strong interference in control and protection system (CPS) rods of BN-1200, but they reduce significantly the reactivity margin for burn-up compensation. This helps compensate all the reactivity balances in the improved core configurations without violating constraints on SVRE value

  9. Value of fast gradient echo MR imaging and contrast-enhanced dynamic studies for the differentiation of adrenal masses

    International Nuclear Information System (INIS)

    Fast gradient echo MR imaging during suspended respiration with various repetition times (TRs), echo times (TEs), and flip angles was performed in 45 patients with 52 adrenal masses. Dynamic perfusion studies after Gd-DTPA administration were achieved by repeated imaging at short intervals. With T2 weighting (TR, 60 msec; TE, 30 msec; flip angle 150), malignant tumors and pheochromocytomas showed a significantly higher relative signal intensity than did adenomas; overlap of signal intensity led to equivocal findings in nine cases. After administration of Gd-DTPA, adenomas showed only mild enhancement and quick washout; malignant tumors as well as pheochromocytomas present strong enhancement, and washout was slower. Five additional cases that were equivocal in precontrast scans could be correctly classified in this way. Thus, besides reduction of acquisition times, fast dynamic contrast-enhanced MR imaging provides further possibilities of adrenal mass classification

  10. Solubility enhancement, physicochemical characterization and formulation of fast-dissolving tablet of nifedipine-betacyclodextrin complexes

    Directory of Open Access Journals (Sweden)

    Swati Changdeo Jagdale

    2012-03-01

    Full Text Available The main objective of the study was to enhance the dissolution of nifedipine, a poorly water soluble drug by betacyclodextrin complexation and to study the effect of the preparation method on the in vitro dissolution profile. The stoichiometric ratio determined by phase solubility analysis for inclusion complexation of nifedipine with β-cyclodextrin was 1:1. Binary complex was prepared by different methods and was further characterized using XRD, DSC and FT-IR. A saturation solubility study was carried out to evaluate the increase in solubility of nifedipine. The optimized complex was formulated into fast-dissolving tablets by using the superdisintegrants Doshion P544, pregelatinized starch, crospovidone, sodium starch glycolate and croscarmellose sodium by direct compression. Tablets were evaluated for friability, hardness, weight variation, disintegration and in vitro dissolution. Tablets showed an enhanced dissolution rate compared to pure nifedipine.Este estudo teve por objetivo principal incrementar a dissolução do nifedipino, fármaco pouco solúvel em água, por meio de sua complexação com β-ciclodextrina e estudar o efeito do método de preparação sobre o perfil de dissolução in vitro. A razão estequiométrica, determinada por ensaio de solubilidade de fase, para a complexação de nifedipino por inclusão em β-ciclodextrina foi 1:1. O complexo binário foi preparado por diferentes métodos, sendo caracterizado utilizando-se difratometria de raios X (XRD, calorimetria diferencial de varredura (DSC e espectroscopia no infravermelho com transformada de Fourier (FT-IR. Realizou-se estudo de solubilidade de saturação para avaliar o incremento da solubilidade do nifedipino. O complexo otimizado foi formulado em comprimidos de dissolução rápida preparados por compressão direta, nos quais se utilizaram os superdesintegrantes Doshion P544, amido pré-gelatinizado, crospovidona, amidoglicolato de sódio e croscarmelose s

  11. Initial evaluation of virtual un-enhanced imaging derived from fast kVp-switching dual energy contrast enhanced CT for the abdomen

    Science.gov (United States)

    Joshi, M.; Mendonca, P.; Okerlund, D.; Lamb, P.; Kulkarni, N.; Pinho, D.; Sahani, D.; Bhotika, R.

    2011-03-01

    The feasibility and utility of creating virtual un-enhanced images from contrast enhanced data acquired using a fast switching dual energy CT acquisition, is explored. Utilizing projection based material decomposition data, monochromatic images are generated and a Multi-material decomposition technique is applied. Quantitative and qualitative evaluation is performed to assess the equivalence of Virtual Un-Enhanced (VUE) and True Un-enhanced (TUE) for multiple tissue types and different organs in the abdomen. Ten patient cases were analyzed where a TUE and a subsequent Contrast Enhanced (CE) acquisition were obtained using fast kVp-switching dual energy CT utilizing Gemstone Spectral Imaging. Quantitative measurements were made by placing multiple Regions of Interest on the different tissues and organs in both the TUE and the VUE images. The absolute Hounsfield Unit (HU) differences in the mean values between TUE & VUE were calculated as well as the differences of the standard deviations. Qualitative analysis was done by two radiologists for overall image quality, presence of residual contrast, appearance of pathology, appearance and contrast of normal tissues and organs in comparison to the TUE. There is a very strong correlation between the TUE and VUE images.

  12. Surface modification of a polyhedral oligomeric silsesquioxane poly(carbonate-urea) urethane (POSS-PCU) nanocomposite polymer as a stent coating for enhanced capture of endothelial progenitor cells.

    OpenAIRE

    Tan, Aaron; Farhatnia, Yasmin; Goh, Debbie; Natasha, G; de Mel, Achala; Lim, Jing; Teoh, Swee-Hin; Malkovskiy, Andrey V; Chawla, Reema; Rajadas, Jayakumar; Cousins, Brian G; Michael R Hamblin; Alavijeh, Mohammad S; Seifalian, Alexander M

    2013-01-01

    An unmet need exists for the development of next-generation multifunctional nanocomposite materials for biomedical applications, particularly in the field of cardiovascular regenerative biology. Herein, we describe the preparation and characterization of a novel polyhedral oligomeric silsesquioxane poly(carbonate-urea) urethane (POSS-PCU) nanocomposite polymer with covalently attached anti-CD34 antibodies to enhance capture of circulating endothelial progenitor cells (EPC). This material may ...

  13. An Analysis of the Distribution and Economics of Oil Fields for Enhanced Oil Recovery-Carbon Capture and Storage

    Science.gov (United States)

    Hall, Kristyn Ann

    The rising carbon dioxide emissions contributing to climate change has lead to the examination of potential ways to mitigate the environmental impact. One such method is through the geological sequestration of carbon (CCS). Although there are several different forms of geological sequestration (i.e. Saline Aquifers, Oil and Gas Reservoirs, Unminable Coal Seams) the current projects are just initiating the large scale-testing phase. The lead entry point into CCS projects is to combine the sequestration with enhanced oil recovery (EOR) due to the improved economic model as a result of the oil recovery and the pre-existing knowledge of the geological structures. The potential scope of CCS-EOR projects throughout the continental United States in terms of a systematic examination of individual reservoir storage potential has not been examined. Instead the majority of the research completed has centered on either estimating the total United States storage potential or the potential of a single specific reservoir. The purpose of this paper is to examine the relationship between oil recovery, carbon dioxide storage and cost during CCS-EOR. The characteristics of the oil and gas reservoirs examined in this study from the Nehring Oil and Gas Database were used in the CCS-EOR model developed by Sean McCoy to estimate the lifting and storage costs of the different reservoirs throughout the continental United States. This allows for an examination of both technical and financial viability of CCS-EOR as an intermediate step for future CCS projects in other geological formations. One option for mitigating climate change is to store industrial CO2 emissions in geologic reservoirs as part of a process known as carbon capture and storage (CCS). There is general consensus that large-scale deployment of CCS would best be initiated by combining geologic sequestration with enhanced oil recovery (EOR), which can use CO2 to improve production from declining oil fields. Revenues from the

  14. Dynamic application of microprojection arrays to skin induces circulating protein extravasation for enhanced biomarker capture and detection.

    Science.gov (United States)

    Coffey, Jacob W; Meliga, Stefano C; Corrie, Simon R; Kendall, Mark A F

    2016-04-01

    Surface modified microprojection arrays are a needle-free alternative to capture circulating biomarkers from the skin in vivo for diagnosis. The concentration and turnover of biomarkers in the interstitial fluid, however, may limit the amount of biomarker that can be accessed by microprojection arrays and ultimately their capture efficiency. Here we report that microprojection array insertion induces protein extravasation from blood vessels and increases the concentration of biomarkers in skin, which can synergistically improve biomarker capture. Regions of blood vessels in skin were identified in the upper dermis and subcutaneous tissue by multi-photon microscopy. Insertion of microprojection array designs with varying projection length (40-190 μm), density (5000-20,408 proj.cm(-2)) and array size (4-36 mm(2)) did not affect the degree of extravasation. Furthermore, the location of extravasated protein did not correlate with projection penetration to these highly vascularised regions, suggesting extravasation was not caused by direct puncture of blood vessels. Biomarker extravasation was also induced by dynamic application of flat control surfaces, and varied with the impact velocity, further supporting this conclusion. The extravasated protein distribution correlated well with regions of high mechanical stress generated during insertion, quantified by finite element models. Using this approach to induce extravasation prior to microprojection array-based biomarker capture, anti-influenza IgG was captured within a 2 min application time, demonstrating that extravasation can lead to rapid biomarker sampling and significantly improved microprojection array capture efficiency. These results have broad implications for the development of transdermal devices that deliver to and sample from the skin. PMID:26826791

  15. A Study of a Modified Histogram Based Fast Enhancement Algorithm (MHBFE)

    OpenAIRE

    Amany A. Kandeel; Alaa M. Abbas; Mohiy M. Hadhoud; Zeiad El-Saghir

    2014-01-01

    Image enhancement is one of the most important issues in low-level image processing. The goal of image enhancement is to improve the quality of an image such that enhanced image is better than the original image. Conventional Histogram equalization (HE) is one of the most algorithms used in the contrast enhancement of medical images, this due to its simplicity and effectiveness. However, it causes the unnatural look and visual artefacts, where it tends to change the brightness of ...

  16. Sensitivity and Resolution Enhanced Solid-State NMR for Paramagnetic Systems and Biomolecules under Very Fast Magic Angle Spinning

    KAUST Repository

    Parthasarathy, Sudhakar

    2013-09-17

    Recent research in fast magic angle spinning (MAS) methods has drastically improved the resolution and sensitivity of NMR spectroscopy of biomolecules and materials in solids. In this Account, we summarize recent and ongoing developments in this area by presenting (13)C and (1)H solid-state NMR (SSNMR) studies on paramagnetic systems and biomolecules under fast MAS from our laboratories. First, we describe how very fast MAS (VFMAS) at the spinning speed of at least 20 kHz allows us to overcome major difficulties in (1)H and (13)C high-resolution SSNMR of paramagnetic systems. As a result, we can enhance both sensitivity and resolution by up to a few orders of magnitude. Using fast recycling (∼ms/scan) with short (1)H T1 values, we can perform (1)H SSNMR microanalysis of paramagnetic systems on the microgram scale with greatly improved sensitivity over that observed for diamagnetic systems. Second, we discuss how VFMAS at a spinning speed greater than ∼40 kHz can enhance the sensitivity and resolution of (13)C biomolecular SSNMR measurements. Low-power (1)H decoupling schemes under VFMAS offer excellent spectral resolution for (13)C SSNMR by nominal (1)H RF irradiation at ∼10 kHz. By combining the VFMAS approach with enhanced (1)H T1 relaxation by paramagnetic doping, we can achieve extremely fast recycling in modern biomolecular SSNMR experiments. Experiments with (13)C-labeled ubiquitin doped with 10 mM Cu-EDTA demonstrate how effectively this new approach, called paramagnetic assisted condensed data collection (PACC), enhances the sensitivity. Lastly, we examine (13)C SSNMR measurements for biomolecules under faster MAS at a higher field. Our preliminary (13)C SSNMR data of Aβ amyloid fibrils and GB1 microcrystals acquired at (1)H NMR frequencies of 750-800 MHz suggest that the combined use of the PACC approach and ultrahigh fields could allow for routine multidimensional SSNMR analyses of proteins at the 50-200 nmol level. Also, we briefly discuss the

  17. Enhancing slow- and fast-light effects in quantum dot semiconductor waveguides through ultrafast dynamics

    DEFF Research Database (Denmark)

    Chen, Yaohui; Mørk, Jesper

    2011-01-01

    In this paper we review our theoretical work on slow and fast light effects in quantum dot semiconductor optical amplifiers (QD SOAs), in particular we investigate the carrier dynamical contributions to the dynamic gain grating and cross gain modulation induced by unique ultrafast inter......-subband carrier dynamics between discrete QD bound states. Our calculations predict that by increasing the injection current density, additional ultra-fast coherent gain contributions around 100GHz arise in contrast to the slow sub-gigahertz carrier density pulsation (CDP) effects. For potential applications in...

  18. Activated carbon enhancement with covalent organic polymers: An innovative material for application in water purification and carbon dioxide capture

    DEFF Research Database (Denmark)

    Mines, Paul D.; Thirion, Damien; Uthuppu, Basil;

    Covalent organic polymers (COPs) have emerged as one of the leading advanced materials for environmental applications, such as the capture and recovery of carbon dioxide and the removal of contaminants from polluted water.1–4 COPs exhibit many remarkable properties that other leading advanced...... materials do not all-encompassing possess. Moreover, COPs have proven to be extremely stable in a wide variety of conditions, i.e. extremely high temperatures and boiling water for weeks at a time, which make them ideal for environmental applications;1 ranging from CO2 capture and recovery to organic......-scale operation, and by retaining the unique properties that only nanomaterials can offer; this novel class of carbon-based materials promises to be a practical and efficient solution to many environmental applications. Herein, we report the functionalization of COPs onto the surface of activated carbon granules...

  19. Activated carbon enhancement with covalent organic polymers: An innovative material for application in water purification and carbon dioxide capture

    OpenAIRE

    Mines, Paul D.; Thirion, Damien; Uthuppu, Basil; Hwang, Yuhoon; Jakobsen, Mogens Havsteen; Andersen, Henrik Rasmus; Yavuz, Cafer T.

    2015-01-01

    Covalent organic polymers (COPs) have emerged as one of the leading advanced materials for environmental applications, such as the capture and recovery of carbon dioxide and the removal of contaminants from polluted water.1–4 COPs exhibit many remarkable properties that other leading advanced materials do not all-encompassing possess. Moreover, COPs have proven to be extremely stable in a wide variety of conditions, i.e. extremely high temperatures and boiling water for weeks at a time, which...

  20. Attentional Control Theory in Childhood: Enhanced Attentional Capture by Non-Emotional and Emotional Distractors in Anxiety and Depression.

    Science.gov (United States)

    Waszczuk, Monika A; Brown, Hannah M; Eley, Thalia C; Lester, Kathryn J

    2015-01-01

    Attentional control theory (ACT) proposes that anxiety is associated with executive functioning deficits. The theory has been widely investigated in adults. The current study tested whether symptoms of childhood anxiety and depression were associated with experimentally measured attentional control in the context of non-emotional and emotional stimuli. Sixty-one children (mean age = 9.23 years, range = 8.39-10.41) reported their trait anxiety and depression symptoms and completed three visual search tasks. The tasks used a variant of an irrelevant singleton paradigm and measured attentional capture by task-irrelevant non-emotional (color) and emotional (facial expressions) distractors. Significant attentional capture by both non-emotional and emotional distractors was observed, and was significantly correlated with trait anxiety and symptoms of depression. The strength of relationship between attentional capture and the symptoms did not differ significantly for non-emotional and emotional distractors. The results suggest that symptoms of childhood anxiety and depression are associated with poorer attentional control both in the presence of emotional and non-emotional stimuli, supporting ACT in younger populations. This attentional deficit in the context of non-emotional information might be as central to childhood internalizing symptoms as attentional biases often observed on tasks investigating processing of emotional stimuli. PMID:26599268

  1. Attentional Control Theory in Childhood: Enhanced Attentional Capture by Non-Emotional and Emotional Distractors in Anxiety and Depression.

    Directory of Open Access Journals (Sweden)

    Monika A Waszczuk

    Full Text Available Attentional control theory (ACT proposes that anxiety is associated with executive functioning deficits. The theory has been widely investigated in adults. The current study tested whether symptoms of childhood anxiety and depression were associated with experimentally measured attentional control in the context of non-emotional and emotional stimuli. Sixty-one children (mean age = 9.23 years, range = 8.39-10.41 reported their trait anxiety and depression symptoms and completed three visual search tasks. The tasks used a variant of an irrelevant singleton paradigm and measured attentional capture by task-irrelevant non-emotional (color and emotional (facial expressions distractors. Significant attentional capture by both non-emotional and emotional distractors was observed, and was significantly correlated with trait anxiety and symptoms of depression. The strength of relationship between attentional capture and the symptoms did not differ significantly for non-emotional and emotional distractors. The results suggest that symptoms of childhood anxiety and depression are associated with poorer attentional control both in the presence of emotional and non-emotional stimuli, supporting ACT in younger populations. This attentional deficit in the context of non-emotional information might be as central to childhood internalizing symptoms as attentional biases often observed on tasks investigating processing of emotional stimuli.

  2. Preparation and characterization of fast dissolving pullulan films containing BCS class II drug nanoparticles for bioavailability enhancement.

    Science.gov (United States)

    Krull, Scott M; Ma, Zhelun; Li, Meng; Davé, Rajesh N; Bilgili, Ecevit

    2016-07-01

    The aim of this study is to assess pullulan as a novel steric stabilizer during the wet-stirred media milling (WSMM) of griseofulvin, a model poorly water-soluble drug, and as a film-former in the preparation of strip films via casting-drying the wet-milled drug suspensions for dissolution and bioavailability enhancement. To this end, pullulan films, with xanthan gum (XG) as thickening agent and glycerin as plasticizer, were loaded with griseofulvin nanoparticles prepared by WSMM using pullulan in combination with sodium dodecyl sulfate (SDS) as an ionic stabilizer. The effects of drug loading and milling time on the particle size and suspension stability were investigated, as well as XG concentration and casting thickness on film properties and dissolution rate. The nanosuspensions prepared with pullulan-SDS combination were relatively stable over 7 days; hence, this combination was used for the film preparation. All pullulan-based strip films exhibited excellent content uniformity (most 5000 cP viscosity. USP IV dissolution tests revealed fast/immediate drug release (t80 < 30 min) from films <120 μm thick. Thinner films, films with lower XG loading, or smaller drug particles led to faster drug dissolution, while drug loading had no discernible effect. Overall, these results suggest that pullulan may serve as an acceptable stabilizer for media milling in combination with surfactant as well as a fast-dissolving film former for the fast release of poorly water-soluble drug nanoparticles. PMID:26567632

  3. Design of a Novel Fluidized Bed Reactor To Enhance Sorbent Performance in CO2 Capture Systems Using CaO

    OpenAIRE

    Diego de Paz, María Elena; Arias Rozada, Borja; Grasa, Gemma; Abanades García, Juan Carlos

    2014-01-01

    This work deals with the modeling and design of a novel bubbling fluidized bed reactor that aims to improve the CO2 carrying capacity of CaO particles in CO2 capture systems by calcium looping (CaL). Inside the new reactor (the recarbonator) the particles that arrive from the carbonator of the CaL system react with a concentrated stream of CO2, thereby increasing their carbonate content up to a certain value, which can be predicted by means of the model proposed. The recarbonator model presen...

  4. High Harmonic Fast Wave Heating Efficiency Enhancement and Current Drive at Longer Wavelength on the National Spherical Torus Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Hosea, J. [Princeton Plasma Physics Laboratory (PPPL); Bell, R. E. [Princeton Plasma Physics Laboratory (PPPL); LeBlanc, B [Princeton Plasma Physics Laboratory (PPPL); Phillips, Cynthia [Princeton Plasma Physics Laboratory (PPPL); Taylor, G. [Princeton Plasma Physics Laboratory (PPPL); Valeo, Dr Ernest [Princeton Plasma Physics Laboratory (PPPL); Wilson, J. R. [Princeton Plasma Physics Laboratory (PPPL); Jaeger, Erwin Frederick [ORNL; Ryan, Philip Michael [ORNL; Wilgen, John B [ORNL; Yuh, H. [Nova Photonics; Levinton, F. [Fusion Physics and Technology; Sabbagh, S. A. [Columbia University; Tritz, K. [Johns Hopkins University; Parker, J. [Cornell University; Bonoli, P. [Massachusetts Institute of Technology (MIT); Harvey, R. W. [CompX, Del Mar, CA

    2008-01-01

    High harmonic fast wave heating and current drive CD are being developed on the National Spherical Torus Experiment M. Ono et al., Nucl. Fusion 41, 1435 2001 for supporting startup and sustainment of the spherical torus plasma. Considerable enhancement of the core heating efficiency from 44% to 65% has been obtained for CD phasing of the antenna strap-to-strap = 90 , k= 8 m 1 by increasing the magnetic field from 4.5 to 5.5 kG. This increase in efficiency is strongly correlated to moving the location of the onset density for perpendicular fast wave propagation nonsetBk 2 / away from the antenna face and wall, and hence reducing the propagating surface wave fields. Radio frequency RF waves propagating close to the wall at lower B and k can enhance power losses from both the parametric decay instability PDI and wave dissipation in sheaths and structures around the machine. The improved efficiency found here is attributed to a reduction in the latter, as PDI losses are little changed at the higher magnetic field. Under these conditions of higher coupling efficiency, initial measurements of localized CD effects have been made and compared with advanced RF code simulations.

  5. Early Progressive Strength Training to Enhance Recovery After Fast-Track Total Knee Arthroplasty

    DEFF Research Database (Denmark)

    Jakobsen, Thomas Linding; Kehlet, Henrik; Husted, Henrik;

    2014-01-01

    OBJECTIVE: To compare 7 weeks of supervised physical rehabilitation with or without progressive strength training (PST) commenced early after fast-track total knee arthroplasty (TKA) on functional performance. METHODS: In total, 82 patients with a unilateral primary TKA were randomized to 2...... from baseline to the 8-week postoperative assessment (primary end point) for the 6-minute walk test with unadjusted baseline scores (mean difference between groups: -11.3 meters [95% confidence interval -45.4, 22.7]; analysis of variance P = 0.51). There were no statistically significant or clinically...

  6. Mesoporous fluorocarbon-modified silica aerogel membranes enabling long-term continuous CO2 capture with large absorption flux enhancements.

    Science.gov (United States)

    Lin, Yi-Feng; Chen, Chien-Hua; Tung, Kuo-Lun; Wei, Te-Yu; Lu, Shih-Yuan; Chang, Kai-Shiun

    2013-03-01

    The use of a membrane contactor combined with a hydrophobic porous membrane and an amine absorbent has attracted considerable attention for the capture of CO2 because of its extensive use, low operational costs, and low energy consumption. The hydrophobic porous membrane interface prevents the passage of the amine absorbent but allows the penetration of CO2 molecules that are captured by the amine absorbent. Herein, highly porous SiO2 aerogels modified with hydrophobic fluorocarbon functional groups (CF3 ) were successfully coated onto a macroporous Al2 O3 membrane; their performance in a membrane contactor for CO2 absorption is discussed. The SiO2 aerogel membrane modified with CF3 functional groups exhibits the highest CO2 absorption flux and can be continuously operated for CO2 absorption for extended periods of time. This study suggests that a SiO2 aerogel membrane modified with CF3 functional groups could potentially be used in a membrane contactor for CO2 absorption. Also, the resulting hydrophobic SiO2 aerogel membrane contactor is a promising technology for large-scale CO2 absorption during the post-combustion process in power plants. PMID:23417984

  7. An Enhanced Two-Stage Impulse Noise Removal Technique based on Fast ANFIS and Fuzzy Decision

    Directory of Open Access Journals (Sweden)

    V. Saradhadevi

    2011-09-01

    Full Text Available Image enhancement plays a vital role in various applications. There are many techniques to remove the noise from the image and produce the clear visual of the image. Moreover, there are several filters and image smoothing techniques available in the literature. All these available techniques have certain limitations. Recently, neural networks are found to be a very efficient tool for image enhancement. A novel two-stage noise removal technique for image enhancement and noise removal is proposed in this paper. In noise removal stage, Adaptive Neuro-Fuzzy Inference System (ANFIS with a Modified Levenberg-Marquardt training algorithm was used to eliminate the impulse noise. The usage of Modified Levenberg-Marquardt training algorithm will reduce the execution time. In the image enhancement stage, the fuzzy decision rules inspired by the Human Visual System (HVS are used to categorize the image pixels into human perception sensitive class and nonsensitive class, and to enhance the quality of the image. The Hyper trapezoidal fuzzy membership function is used in the proposed technique. In order to improve the sensitive regions with higher visual quality, a Neural Network (NN is proposed. The experiment is conducted with standard image. It is observed from the experimental result that the proposed FANFIS shows significant performance when compared to existing methods.

  8. Enhanced therapeutic effect on murine melanoma and angiosarcoma cells by boron neutron capture therapy using a boronated metalloporphyrin

    International Nuclear Information System (INIS)

    We have already achieved successful treatment of several human patients with malignant melanoma by boron neutron capture therapy (BNCT) using 10B1-paraboronophenylalanine (10B1-BPA·HCl). In this study we used a new compound, a manganese boronated protoporphyrin (Mn-10BOPP), and compared it to 10B1-BPA·HCl with respect to uptake in murine melanoma and angiosarcoma cells as well as to their cell killing effect. 10B uptake was measured in a new method, and the new compound was much more incorporated into both cells than 10B1-BPA·HCl. Furthermore, melanoma and angiosarcoma cells preincubated with the new compound were 15 to 20 times more efficiently killed by BNCT than cells preincubated with 10B1-BPA·HCl. (author)

  9. Metastable enhancement of C{sup +} and O{sup +} capture reactions. Final technical report, June 1987--September 1990

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, E.W.; Moran, T.F.

    1990-09-01

    Single electron capture by 10- to 500-eV singly charged C and O ions traversing targets of H{sub 2} and H was studied with emphasis on comparing cross sections for metastable species with those for the ground state. For an H{sub 2} target cross sections are of the order 10{Angstrom} and 20 to 30 times larger than for ground state species. Electron impact ion sources typically produce 5 to 30% of their output in the metastable state. Previous published work has largely ignored (or failed to detect) the presence of metastables and is incorrect by as much as an order of magnitude. Discrepancies between data sets have been resolved, and a reliable data set is provided for energies from 10 to 10{sup 5} eV. Similar experiments for an atomic H target are underway. It is proposed to extend the program to similar studies with multiply charged projectile species.

  10. Advance chromatin extraction enhances performance and productivity of cation exchange chromatography-based capture of Immunoglobulin G monoclonal antibodies.

    Science.gov (United States)

    Nian, Rui; Gagnon, Pete

    2016-07-01

    The impact of host cell-derived chromatin was investigated on the performance and productivity of cation exchange chromatography as a method for capture-purification of an IgG monoclonal antibody. Cell culture supernatant was prepared for loading by titration to pH 6.0, dilution with water to a conductivity of 4mS/cm, then microfiltration to remove solids. DNA content was reduced 99% to 30ppm, histone host cell protein content by 76% to 6300ppm, non-histone host cell protein content by 15% to 321,000ppm, and aggregates from 33% to 15%. IgG recovery was 83%. An alternative preparation was performed, adding octanoic acid, allantoin, and electropositive particles to the harvest at pH 5.3, then removing solids. DNA content was reduced to<1 ppb, histones became undetectable, non-histones were reduced to 24,000ppm, and aggregates were reduced to 2.4%. IgG recovery was 95%. This treatment increased dynamic capacity (DBC) of cation exchange capture to 173g/L and enabled the column to reduce non-histone host proteins to 671ppm. Step recovery was 99%. A single multimodal polishing step further reduced them to 15ppm and aggregates to <0.1%. Overall process recovery was 89%. Productivity at feed stream IgG concentrations of 5-10g/L was roughly double the productivity of a same-size protein A column with a DBC of 55g/L. PMID:27247214

  11. Surface-enhanced Raman scattering (SERS) detection of multiple viral antigens using magnetic capture of SERS-active nanoparticles

    Science.gov (United States)

    A highly sensitive immunoassay based on surface-enhanced Raman scattering (SERS) spectroscopy has been developed for multiplex detection of surface envelope and capsid antigens of the viral zoonotic pathogens West Nile virus (WNV) and Rift Valley fever virus (RVFV). Detection was mediated by antibo...

  12. Enhancement of asynchronous release from fast-spiking interneuron in human and rat epileptic neocortex.

    Directory of Open Access Journals (Sweden)

    Man Jiang

    Full Text Available Down-regulation of GABAergic inhibition may result in the generation of epileptiform activities. Besides spike-triggered synchronous GABA release, changes in asynchronous release (AR following high-frequency discharges may further regulate epileptiform activities. In brain slices obtained from surgically removed human neocortical tissues of patients with intractable epilepsy and brain tumor, we found that AR occurred at GABAergic output synapses of fast-spiking (FS neurons and its strength depended on the type of connections, with FS autapses showing the strongest AR. In addition, we found that AR depended on residual Ca²⁺ at presynaptic terminals but was independent of postsynaptic firing. Furthermore, AR at FS autapses was markedly elevated in human epileptic tissue as compared to non-epileptic tissue. In a rat model of epilepsy, we found similar elevation of AR at both FS autapses and synapses onto excitatory neurons. Further experiments and analysis showed that AR elevation in epileptic tissue may result from an increase in action potential amplitude in the FS neurons and elevation of residual Ca²⁺ concentration. Together, these results revealed that GABAergic AR occurred at both human and rat neocortex, and its elevation in epileptic tissue may contribute to the regulation of epileptiform activities.

  13. Enhancement of biomass conversion in catalytic fast pyrolysis by microwave-assisted formic acid pretreatment.

    Science.gov (United States)

    Feng, Yu; Li, Guangyu; Li, Xiangyu; Zhu, Ning; Xiao, Bo; Li, Jian; Wang, Yujue

    2016-08-01

    This study investigated microwave-assisted formic acid (MW-FA) pretreatment as a possible way to improve aromatic production from catalytic fast pyrolysis (CFP) of lignocellulosic biomass. Results showed that short duration of MW-FA pretreatment (5-10min) could effectively disrupt the recalcitrant structure of beech wood and selectively remove its hemicellulose and lignin components. This increased the accessibility of cellulose component of biomass to subsequent thermal conversion in CFP. Consequently, the MW-FA pretreated beech wood produced 14.0-28.3% higher yields (26.4-29.8C%) for valuable aromatic products in CFP than the untreated control (23.2C%). In addition, the yields of undesired solid residue (char/coke) decreased from 33.1C% for the untreated control to 28.6-29.8C% for the MW-FA pretreated samples. These results demonstrate that MW-FA pretreatment can provide an effective way to improve the product distribution from CFP of lignocellulose. PMID:27176672

  14. Energy enhancement for deuteron beam fast ignition of a precompressed inertial confinement fusion target

    International Nuclear Information System (INIS)

    Fast Ignition (FI) is recognized as a potentially promising approach to achieve the high-energy-gain target performance needed for commercial inertial confinement fusion. Here we consider deuteron beam driven FI which provides not only the 'hot spot' ignition spark, but also extra ''bonus'' fusion energy through reactions in the target. In this study, we estimate the impact of the added deposition energy due to the fusion reactions occurring, based on calculations using a modified energy multiplication factor Fc. The deuteron beam energy deposition range and time are also evaluated in order to estimate the desired deuteron initial energy. It is shown that an average of 30% extra energy can be gained from deuterons with 1 MeV initial energy and 12% from deuterons with 3 MeV initial energy. These results indicate that the energy benefit of this approach could be significant, but a much more comprehensive calculation is needed to realize a full 3D design for realistic experimental studies.

  15. Runaway electron generation as possible trigger for enhancement of magnetohydrodynamic plasma activity and fast changes in runaway beam behavior

    Energy Technology Data Exchange (ETDEWEB)

    Pankratov, I. M., E-mail: pankratov@kipt.kharkov.ua, E-mail: rjzhou@ipp.ac.cn [Institute of Plasma Physics, NSC Kharkov Institute of Physics and Technology, Academicheskaya Str. 1, 61108 Kharkov (Ukraine); Zhou, R. J., E-mail: pankratov@kipt.kharkov.ua, E-mail: rjzhou@ipp.ac.cn; Hu, L. Q. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)

    2015-07-15

    Peculiar phenomena were observed during experiments with runaway electrons: rapid changes in the synchrotron spot and its intensity that coincided with stepwise increases in the electron cyclotron emission (ECE) signal (cyclotron radiation of suprathermal electrons). These phenomena were initially observed in TEXTOR (Tokamak Experiment for Technology Oriented Research), where these events only occurred in the current decay phase or in discharges with thin stable runaway beams at a q = 1 drift surface. These rapid changes in the synchrotron spot were interpreted by the TEXTOR team as a fast pitch angle scattering event. Recently, similar rapid changes in the synchrotron spot and its intensity that coincided with stepwise increases in the non-thermal ECE signal were observed in the EAST (Experimental Advanced Superconducting Tokamak) runaway discharge. Runaway electrons were located around the q = 2 rational magnetic surface (ring-like runaway electron beam). During the EAST runaway discharge, stepwise ECE signal increases coincided with enhanced magnetohydrodynamic (MHD) activity. This behavior was peculiar to this shot. In this paper, we show that these non-thermal ECE step-like jumps were related to the abrupt growth of suprathermal electrons induced by bursting electric fields at reconnection events during this MHD plasma activity. Enhancement of the secondary runaway electron generation also occurred simultaneously. Local changes in the current-density gradient appeared because of local enhancement of the runaway electron generation process. These current-density gradient changes are considered to be a possible trigger for enhancement of the MHD plasma activity and the rapid changes in runaway beam behavior.

  16. Runaway electron generation as possible trigger for enhancement of magnetohydrodynamic plasma activity and fast changes in runaway beam behavior

    International Nuclear Information System (INIS)

    Peculiar phenomena were observed during experiments with runaway electrons: rapid changes in the synchrotron spot and its intensity that coincided with stepwise increases in the electron cyclotron emission (ECE) signal (cyclotron radiation of suprathermal electrons). These phenomena were initially observed in TEXTOR (Tokamak Experiment for Technology Oriented Research), where these events only occurred in the current decay phase or in discharges with thin stable runaway beams at a q = 1 drift surface. These rapid changes in the synchrotron spot were interpreted by the TEXTOR team as a fast pitch angle scattering event. Recently, similar rapid changes in the synchrotron spot and its intensity that coincided with stepwise increases in the non-thermal ECE signal were observed in the EAST (Experimental Advanced Superconducting Tokamak) runaway discharge. Runaway electrons were located around the q = 2 rational magnetic surface (ring-like runaway electron beam). During the EAST runaway discharge, stepwise ECE signal increases coincided with enhanced magnetohydrodynamic (MHD) activity. This behavior was peculiar to this shot. In this paper, we show that these non-thermal ECE step-like jumps were related to the abrupt growth of suprathermal electrons induced by bursting electric fields at reconnection events during this MHD plasma activity. Enhancement of the secondary runaway electron generation also occurred simultaneously. Local changes in the current-density gradient appeared because of local enhancement of the runaway electron generation process. These current-density gradient changes are considered to be a possible trigger for enhancement of the MHD plasma activity and the rapid changes in runaway beam behavior

  17. Carbon capture and biogas enhancement by carbon dioxide enrichment of anaerobic digesters treating sewage sludge or food waste

    OpenAIRE

    Bajón, Fernández Y; Soares, Ana; Villa, Raffaella; Vale, P; Cartmell, Elise

    2014-01-01

    The increasing concentration of carbon dioxide (CO2) in the atmosphere and the stringent greenhouse gases (GHG) reduction targets, require the development of CO2 sequestration technologies applicable for the waste and wastewater sector. This study addressed the reduction of CO2 emissions and enhancement of biogas production associated with CO2 enrichment of anaerobic digesters (ADs). The benefits of CO2 enrichment were examined by injecting CO2 at 0, 0.3, 0.6 and 0.9M fractions into batch ADs...

  18. Fast reversible single-step method for enhanced band contrast of polyacrylamide gels for automated detection.

    Science.gov (United States)

    Ling, Wei-Li; Lua, Wai-Heng; Gan, Samuel Ken-En

    2015-05-01

    Staining SDS-PAGE is commonly used in protein analysis for many downstream characterization processes. Although staining and destaining protocols can be adjusted, they can be laborious, and faint bands often become false negatives. Similarly, these faint bands hinder automated software band detections that are necessary for quantitative analyses. To overcome these problems, we describe a single-step rapid and reversible method to increase (up to 500%) band contrast in stained gels. Through the use of alcohols, we improved band detection and facilitated gel storage by drying the gels into compact white sheets. This method is suitable for all stained SDS-PAGE gels, including gradient gels and is shown to improve automated band detection by enhanced band contrast. PMID:25782090

  19. Enhanced capture of healthcare-related harms and injuries in the 11th revision of the International Classification of Diseases (ICD-11).

    Science.gov (United States)

    Southern, Danielle A; Pincus, Harold A; Romano, Patrick S; Burnand, Bernard; Harrison, James; Forster, Alan J; Moskal, Lori; Quan, Hude; Droesler, Saskia E; Sundararajan, Vijaya; Colin, Cyrille; Gurevich, Yana; Brien, Susan E; Kostanjsek, Nenad; Üstün, Bedirhan; Ghali, William A

    2016-02-01

    The World Health Organization (WHO) plans to submit the 11th revision of the International Classification of Diseases (ICD) to the World Health Assembly in 2018. The WHO is working toward a revised classification system that has an enhanced ability to capture health concepts in a manner that reflects current scientific evidence and that is compatible with contemporary information systems. In this paper, we present recommendations made to the WHO by the ICD revision's Quality and Safety Topic Advisory Group (Q&S TAG) for a new conceptual approach to capturing healthcare-related harms and injuries in ICD-coded data. The Q&S TAG has grouped causes of healthcare-related harm and injuries into four categories that relate to the source of the event: (a) medications and substances, (b) procedures, (c) devices and (d) other aspects of care. Under the proposed multiple coding approach, one of these sources of harm must be coded as part of a cluster of three codes to depict, respectively, a healthcare activity as a 'source' of harm, a 'mode or mechanism' of harm and a consequence of the event summarized by these codes (i.e. injury or harm). Use of this framework depends on the implementation of a new and potentially powerful code-clustering mechanism in ICD-11. This new framework for coding healthcare-related harm has great potential to improve the clinical detail of adverse event descriptions, and the overall quality of coded health data. PMID:26660444

  20. Enhanced performance of a biomimetic membrane for Na2CO3 crystallization in the scenario of CO2 capture

    DEFF Research Database (Denmark)

    Ye, Wenyuan; Lin, Jiuyang; Tækker Madsen, Henrik;

    2016-01-01

    Membrane assisted crystallization (MACr) offers an innovative platform for crystallizing Na2CO3, allowing its reuse after CO2 capture from flue gases by an alkaline solution (i.e., NaOH). In this study, the biomimetic aquaporin Inside™ membrane AIM60 was employed to enhance water removal......, facilitating Na2CO3 crystallization. The water channel in the active layer, comprising aquaporin proteins, and the strong wettability of membrane substrate assist a better performance. For instance, the water flux of AIM60 membrane for concentrating a 1.89molL-1 Na2CO3 solution (osmotic pressure of 94.8bar......, a proper control of the supersaturation level induces crystallization of Na2CO3·10H2O crystals with a purity of 99.94%. Hence, the aquaporin Inside™ FO membrane may be a promising alternative to existing methods for Na2CO3 crystallization for its application in a CO2 capture scenario....

  1. Surface modification of a polyhedral oligomeric silsesquioxane poly(carbonate-urea) urethane (POSS-PCU) nanocomposite polymer as a stent coating for enhanced capture of endothelial progenitor cells.

    Science.gov (United States)

    Tan, Aaron; Farhatnia, Yasmin; Goh, Debbie; G, Natasha; de Mel, Achala; Lim, Jing; Teoh, Swee-Hin; Malkovskiy, Andrey V; Chawla, Reema; Rajadas, Jayakumar; Cousins, Brian G; Hamblin, Michael R; Alavijeh, Mohammad S; Seifalian, Alexander M

    2013-12-01

    An unmet need exists for the development of next-generation multifunctional nanocomposite materials for biomedical applications, particularly in the field of cardiovascular regenerative biology. Herein, we describe the preparation and characterization of a novel polyhedral oligomeric silsesquioxane poly(carbonate-urea) urethane (POSS-PCU) nanocomposite polymer with covalently attached anti-CD34 antibodies to enhance capture of circulating endothelial progenitor cells (EPC). This material may be used as a new coating for bare metal stents used after balloon angioplasty to improve re-endothelialization. Biophysical characterization techniques were used to assess POSS-PCU and its subsequent functionalization with anti-CD34 antibodies. Results indicated successful covalent attachment of anti-CD34 antibodies on the surface of POSS-PCU leading to an increased propensity for EPC capture, whilst maintaining in vitro biocompatibility and hemocompatibility. POSS-PCU has already been used in 3 first-in-man studies, as a bypass graft, lacrimal duct and a bioartificial trachea. We therefore postulate that its superior biocompatibility and unique biophysical properties would render it an ideal candidate for coating medical devices, with stents as a prime example. Taken together, anti-CD34 functionalized POSS-PCU could form the basis of a nano-inspired polymer platform for the next generation stent coatings. PMID:24706135

  2. Carbon capture and biogas enhancement by carbon dioxide enrichment of anaerobic digesters treating sewage sludge or food waste.

    Science.gov (United States)

    Bajón Fernández, Y; Soares, A; Villa, R; Vale, P; Cartmell, E

    2014-05-01

    The increasing concentration of carbon dioxide (CO2) in the atmosphere and the stringent greenhouse gases (GHG) reduction targets, require the development of CO2 sequestration technologies applicable for the waste and wastewater sector. This study addressed the reduction of CO2 emissions and enhancement of biogas production associated with CO2 enrichment of anaerobic digesters (ADs). The benefits of CO2 enrichment were examined by injecting CO2 at 0, 0.3, 0.6 and 0.9 M fractions into batch ADs treating food waste or sewage sludge. Daily specific methane (CH4) production increased 11-16% for food waste and 96-138% for sewage sludge over the first 24h. Potential CO2 reductions of 8-34% for sewage sludge and 3-11% for food waste were estimated. The capacity of ADs to utilise additional CO2 was demonstrated, which could provide a potential solution for onsite sequestration of CO2 streams while enhancing renewable energy production. PMID:24632434

  3. Rolling stones. Fast weathering of olivine in shallow seas for cost-effective CO2 capture and mitigation of global warming and ocean acidification

    Energy Technology Data Exchange (ETDEWEB)

    Schuiling, R.D.; De Boer, P.L. [Department of Earth Sciences, Utrecht University, P.O. Box 80.021, 3508TA Utrecht (Netherlands)

    2011-07-01

    Human CO2 emissions may drive the Earth into a next greenhouse state. They can be mitigated by accelerating weathering of natural rock under the uptake of CO2. We disprove the paradigm that olivine weathering in nature would be a slow process, and show that it is not needed to mill olivine to very fine, 10 {mu}m-size grains in order to arrive at a complete dissolution within 1-2 year. In high-energy shallow marine environments olivine grains and reaction products on the grain surfaces, that otherwise would greatly retard the reaction, are abraded so that the chemical reaction is much accelerated. When kept in motion even large olivine grains rubbing and bumping against each other quickly produce fine clay- and silt-sized olivine particles that show a fast chemical reaction. Spreading of olivine in the world's 2% most energetic shelf seas can compensate a year's global CO2 emissions and counteract ocean acidification against a price well below that of carbon credits.

  4. Enhanced kinetics for the clathrate process in a fixed bed reactor in the presence of liquid promoters for pre-combustion carbon dioxide capture

    International Nuclear Information System (INIS)

    In this work, we present enhanced kinetics of hydrate formation for the clathrate process in the presence of two liquid promoters namely THF (tetrahydrofuran) and TBAB (tetra-n-butyl ammonium bromide) in a FBR (fixed bed reactor) for pre-combustion capture of CO2. Silica sand was used as a medium to capture CO2 from CO2/H2 gas mixture by hydrate crystallisation. Experiments were performed at different temperatures (274.2 K and 279.2 K) and 6.0 MPa to determine the total gas uptake, induction time and rate of hydrate formation. The observed trends indicated that higher driving force resulted in higher gas consumption and significantly reduced induction time. For the same driving force, higher gas consumption and shorter induction time was achieved by THF as compared to TBAB. 5.53 mol% THF attained higher gas consumption than 1.0 mol% THF whereas 3.0 mol% TBAB attained lower gas consumption than 0.3 mol% TBAB. A highest gas uptake of 51.95 (±5.183) mmol of gas/mol of water and a highest rate of 51.21(±8.91) mol.min−1.m−3 were obtained for 5.53 mol% THF at 6.0 MPa and 279.2 K. Overall, this study indicated better hydrate formation kinetics with the use of THF in an FBR configuration for CO2 capture from a fuel gas mixture. - Highlights: • Better kinetic performance with THF compared to TBAB for CO2 capture in a fixed bed reactor. • Highest CO2 uptake (126.99 ± 12.67 mg of gas/g of water) was obtained for 5.53 mol% THF. • Highest growth rate (51.21 ± 8.91 mol min−1.m−3) for 30 min was obtained for 5.53 mol% THF. • Waste heat (ΔT = 20) is sufficient to recover all the hydrated gas

  5. Enhanced performance of fast-response 3-hole wedge probes for transonic flows in axial turbomachinery

    Energy Technology Data Exchange (ETDEWEB)

    Delhaye, D.; Paniagua, G. [von Karman Institute for Fluid Dynamics, Turbomachinery and Propulsion Department, Rhode-Saint-Genese (Belgium); Fernandez Oro, J.M. [Universidad de Oviedo, Area de Mecanica de Fluidos, Gijon (Spain); Denos, R. [European Commission, Directorate General for Research, Brussels (Belgium)

    2011-01-15

    The paper presents the development and application of a three-sensor wedge probe to measure unsteady aerodynamics in a transonic turbine. CFD has been used to perform a detailed uncertainty analysis related to probe-induced perturbations, in particular the separation zones appearing on the wedge apex. The effects of the Reynolds and Mach numbers are studied using both experimental data together with CFD simulations. The angular range of the probe and linearity of the calibration maps are enhanced with a novel zonal calibration technique, used for the first time in compressible flows. The data reduction methodology is explained and demonstrated with measurements performed in a single-stage high-pressure turbine mounted in the compression tube facility of the von Karman Institute. The turbine was operated at subsonic and transonic pressure ratios (2.4 and 5.1) for a Reynolds number of 10{sup 6}, representative of modern engine conditions. Complete maps of the unsteady flow angle and rotor outlet Mach number are documented. These data allow the study of secondary flows and rotor trailing edge shocks. (orig.)

  6. Global cooperation and conceptual design toward GNEP. Enhanced TRU burning fast reactor

    International Nuclear Information System (INIS)

    In support of the GNEP (Global Nuclear Energy Partnership) program, AREVA and Mitsubishi Heavy Industries, Ltd. (MHI) seek to develop an ARR (Advanced Recycling Reactor) in concern with a CFTC (Consolidated Fuel Treatment Facility). This report presents the examination of more effective transuranics (TRU) burning core. Therefore some innovative technologies have been examined under the safety requirements; MA bearing fuel with 50% TRU fraction, moderator pin, fuel of high Am fraction, and Am blanket. The function of moderator is to enhance TRU burning capability, while increasing the Doppler effect and reducing the positive sodium void effect. The aim of 50% TRU fraction is to increase TRU burning capability by curbing plutonium production. Both high Am fraction of fuel and Am blanket can promote Am transmutation. According to the detailed calculation of high TRU (MA 15%, Pu 35% average) contained oxide fueled core with moderator pins of 12% arranged driver fuel assemblies, TRU conversion ratio decreases down to 0.33 and TRU burning capability is improved to 67kg/TWeh. Deploying Am blanket which is oxide fuel with Am 50% and U 50%, the total of Am transmutation capability becomes 69 kg/TWeh. (author)

  7. A fast and reliable readout method for quantitative analysis of surface-enhanced Raman scattering nanoprobes on chip surface

    International Nuclear Information System (INIS)

    Surface-enhanced Raman scattering techniques have been widely used for bioanalysis due to its high sensitivity and multiplex capacity. However, the point-scanning method using a micro-Raman system, which is the most common method in the literature, has a disadvantage of extremely long measurement time for on-chip immunoassay adopting a large chip area of approximately 1-mm scale and confocal beam point of ca. 1-μm size. Alternative methods such as sampled spot scan with high confocality and large-area scan method with enlarged field of view and low confocality have been utilized in order to minimize the measurement time practically. In this study, we analyzed the two methods in respect of signal-to-noise ratio and sampling-led signal fluctuations to obtain insights into a fast and reliable readout strategy. On this basis, we proposed a methodology for fast and reliable quantitative measurement of the whole chip area. The proposed method adopted a raster scan covering a full area of 100 μm × 100 μm region as a proof-of-concept experiment while accumulating signals in the CCD detector for single spectrum per frame. One single scan with 10 s over 100 μm × 100 μm area yielded much higher sensitivity compared to sampled spot scanning measurements and no signal fluctuations attributed to sampled spot scan. This readout method is able to serve as one of key technologies that will bring quantitative multiplexed detection and analysis into practice

  8. A fast and reliable readout method for quantitative analysis of surface-enhanced Raman scattering nanoprobes on chip surface

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Hyejin; Jeong, Sinyoung; Ko, Eunbyeol; Jeong, Dae Hong, E-mail: yslee@snu.ac.kr, E-mail: debobkr@gmail.com, E-mail: jeongdh@snu.ac.kr [Department of Chemistry Education, Seoul National University, Seoul 151-742 (Korea, Republic of); Kang, Homan [Interdisciplinary Program in Nano-Science and Technology, Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, Yoon-Sik, E-mail: yslee@snu.ac.kr, E-mail: debobkr@gmail.com, E-mail: jeongdh@snu.ac.kr [Interdisciplinary Program in Nano-Science and Technology, Seoul National University, Seoul 151-742 (Korea, Republic of); School of Chemical and Biological Engineering, Seoul National University, Seoul 151-742 (Korea, Republic of); Lee, Ho-Young, E-mail: yslee@snu.ac.kr, E-mail: debobkr@gmail.com, E-mail: jeongdh@snu.ac.kr [Department of Nuclear Medicine, Seoul National University Bundang Hospital, Seongnam 463-707 (Korea, Republic of)

    2015-05-15

    Surface-enhanced Raman scattering techniques have been widely used for bioanalysis due to its high sensitivity and multiplex capacity. However, the point-scanning method using a micro-Raman system, which is the most common method in the literature, has a disadvantage of extremely long measurement time for on-chip immunoassay adopting a large chip area of approximately 1-mm scale and confocal beam point of ca. 1-μm size. Alternative methods such as sampled spot scan with high confocality and large-area scan method with enlarged field of view and low confocality have been utilized in order to minimize the measurement time practically. In this study, we analyzed the two methods in respect of signal-to-noise ratio and sampling-led signal fluctuations to obtain insights into a fast and reliable readout strategy. On this basis, we proposed a methodology for fast and reliable quantitative measurement of the whole chip area. The proposed method adopted a raster scan covering a full area of 100 μm × 100 μm region as a proof-of-concept experiment while accumulating signals in the CCD detector for single spectrum per frame. One single scan with 10 s over 100 μm × 100 μm area yielded much higher sensitivity compared to sampled spot scanning measurements and no signal fluctuations attributed to sampled spot scan. This readout method is able to serve as one of key technologies that will bring quantitative multiplexed detection and analysis into practice.

  9. The Hamburg/ESO R-process Enhanced Star survey (HERES). I. Project description, and discovery of two stars with strong enhancements of neutron-capture elements

    CERN Document Server

    Christlieb, N; Barklem, P S; Bessell, M; Hill, V; Holmberg, J; Korn, A J; Marsteller, B; Mashonkina, L I; Qian, Y Z; Rossi, S; Wasserburg, G J; Zickgraf, F J; Kratz, K L; Nordström, B; Pfeiffer, B; Rhee, J; Ryan, S G

    2004-01-01

    We report on a dedicated effort to identify and study metal-poor stars strongly enhanced in r-process elements ([r/Fe] > 1 dex; hereafter r-II stars), the Hamburg/ESO R-process Enhanced Star survey (HERES). Moderate-resolution (~2A) follow-up spectroscopy has been obtained for metal-poor giant candidates selected from the Hamburg/ESO objective-prism survey (HES) as well as the HK survey to identify sharp-lined stars with [Fe/H] < -2.5dex. For several hundred confirmed metal-poor giants brighter than B~16.5mag (most of them from the HES), ``snapshot'' spectra (R~20,000; S/N~30 per pixel) are being obtained with VLT/UVES, with the main aim of finding the 2-3% r-II stars expected to be among them. These are studied in detail by means of higher resolution and higher S/N spectra. In this paper we describe a pilot study based on a set of 35 stars, including 23 from the HK survey, 8 from the HES, and 4 comparison stars. We discovered two new r-II stars, CS29497-004 ([Eu/Fe] = 1.64 +/- 0.22) and CS29491-069 ([Eu/F...

  10. Exploring enhanced menu labels' influence on fast food selections and exercise-related attitudes, perceptions, and intentions.

    Science.gov (United States)

    Lee, Morgan S; Thompson, Joel Kevin

    2016-10-01

    Labeling restaurant menus with calorie counts is a popular public health intervention, but research shows these labels have small, inconsistent effects on behavior. Supplementing calorie counts with physical activity equivalents may produce stronger results, but few studies of these enhanced labels have been conducted, and the labels' potential to influence exercise-related outcomes remains unexplored. This online study evaluated the impact of no information, calories-only, and calories plus equivalent miles of walking labels on fast food item selection and exercise-related attitudes, perceptions, and intentions. Participants (N = 643) were randomly assigned to a labeling condition and completed a menu ordering task followed by measures of exercise-related outcomes. The labels had little effect on ordering behavior, with no significant differences in total calories ordered and counterintuitive increases in calories ordered in the two informational conditions in some item categories. The labels also had little impact on the exercise-related outcomes, though participants in the two informational conditions perceived exercise as less enjoyable than did participants in the no information condition, and trends following the same pattern were found for other exercise-related outcomes. The present findings concur with literature demonstrating small, inconsistent effects of current menu labeling strategies and suggest that alternatives such as traffic light systems should be explored. PMID:27289007

  11. Response of Chinese hamster ovary cells to fast neutron radiotherapy beams. I. Relative biological effectiveness and oxygen enhancement ratio

    International Nuclear Information System (INIS)

    The relative biological effectiveness (RBE) and oxygen enhancement ratio (OER) were determined for fast neutron beams produced by both 16-MeV and 50-MeV 2H on Be at the Texas A and M Variable Energy Cyclotron (TAMVEC). These beams have average neutron energies of 7 and 21 MeV, respectively. The biological system used in these experiments was Chinese hamster ovary cells in tissue culture. The results indicated that although the RBE of the 21-MeV beam was about 15 percent lower than that for the 7-MeV beam at 0.1 percent survival there was no change in RBE for either beam with depth in a tissue-equivalent phantom. The OER of the 7-MeV beam was found to be 1.5 +- 0.3 and the 21-MeV beam had an OER of 1.2 +- 0.2, which resulted in gain factors of 1.7 and 2.1, respectively, when compared to 60Co gamma rays (OER = 2.5). No variation in OER with depth was detected. It was concluded that the 21-MeV TAMVEC beam should be as applicable to radiotherapy from the radiobiological point of view as a 7-MeV beam

  12. Nasolacrimal system: evaluation with gadolinium-enhanced MR dacryocystography with a three-dimensional fast spoiled gradient-recalled technique

    International Nuclear Information System (INIS)

    The aim of this study was to determine the diagnostic accuracy of gadolinium-enhanced three-dimensional (3D) fast spoiled gradient-recalled (FSPGR) MR dacryocystography in patients with epiphora. Bilateral nasolacrimal systems of 19 patients suspected of having nasolacrimal canal obstruction were evaluated with MR dacryocystography. A sterile 0.9% NaCl solution containing 1:100 diluted gadolinium chelate was instilled into the bilateral conjunctival sacs of the patients. The 3D FSPGR sequence was used with 1.0-T scanner with the following parameters: TR 9.3 ms; TE 2 ms; flip angle 20; 256 x 224 matrix; 13- or 26-cm field of view; and 1-mm slice thickness. Seventeen patients had digital dacryocystography for comparison which we considered standard of reference. Thirty-four nasolacrimal systems were evaluated with MR and digital dacryocystography. Discrepancies between the findings of both methods were detected in 2 patients. The overall sensitivity of MR in detecting the obstruction was 100%. Magnetic resonance helped to determine the canalicular and ductal obstruction in 100% of the patients and the saccular obstruction in 80% of the patients. We conclude that 3D FSGR technique for MR dacryocystography is a reliable and noninvasive method in the evaluation of the obstruction level in the lacrimal system in patients with epiphora. (orig.)

  13. MRI of the uterus, uterine cervix, and vagina: diagnostic performance of dynamic contrast-enhanced fast multiplanar gradient-echo imaging in comparison with fast spin-echo T2-weighted pulse imaging

    International Nuclear Information System (INIS)

    The aim of this study was to compare the diagnostic performance of contrast-enhanced fast multiplanar gradient-echo (GRE) and T2-weighted fast spin-echo (FSE) image sets in the assessment of uterus, cervix, and vagina. Fast (up to 20 contiguous sections in 23 s) multiplanar GRE and FSE images of 45 patients referred for imaging of the female pelvis were evaluated retrospectively with regard to overall image quality and the ability to detect normal anatomic structures, as well as lesion conspicuity. Results were compared with histologic findings (n = 29) or clinical follow-up. Furthermore, a quantitative assessment of contrast-to-noise ratios among normal uterine and cervical structures as well as uterine lesions was performed for both sequences. On GRE images, uterine and cervical differentiation was best seen on the image sets acquired 15 and 60 s following contrast enhancement and results were significantly better compared with delayed images (p 2 test, the difference in diagnostic performance between FSE and GRE revealed no significant difference, whereas the combination of both techniques performed better than FSE imaging alone (p < 0.05). The presented data suggest that dynamic contrast-enhanced GRE imaging should be part of an MR examination of the female pelvis. Combined GRE and FSE imaging provide an excellent sensitivity in the assessment of uterine and vaginal pathologies. (orig.) (orig.)

  14. Estimation of perilymph enhancement after intratympanic administration of Gd-DTPA by fast T1-mapping with a dual flip angle 3D spoiled gradient echo sequence

    International Nuclear Information System (INIS)

    Eleven patients with suspected Meniere's disease received intratympanic (IT) administration of gadolinium (gadopentetate dimeglumine; Gd) prior to acquisition of 3-dimensional (3D) fluid-attenuated inversion recovery (FLAIR), 3D real inversion recovery (IR), and fast T1 mapping by dual flip angle 3D gradient echo (FT1-map) imaging sequences to evaluate the degree of perilymph enhancement. Though 3-dimensional FLAIR could detect lower concentrations of gadolinium than 3D real IR, in 2 patients, poor enhancement still prevented visualization of the endolymphatic space using 3D FLAIR. We could predict poor contrast enhancement in these 2 patients using the FT1-map technique. (author)

  15. Laser capture.

    Science.gov (United States)

    Potter, S Steven; Brunskill, Eric W

    2012-01-01

    This chapter describes detailed methods used for laser capture microdissection (LCM) of discrete subpopulations of cells. Topics covered include preparing tissue blocks, cryostat sectioning, processing slides, performing the LCM, and purification of RNA from LCM samples. Notes describe the fine points of each operation, which can often mean the difference between success and failure. PMID:22639264

  16. Assessing innovation in emerging energy technologies: Socio-technical dynamics of carbon capture and storage (CCS) and enhanced geothermal systems (EGS) in the USA

    International Nuclear Information System (INIS)

    This study applies a socio-technical systems perspective to explore innovation dynamics of two emerging energy technologies with potential to reduce greenhouse gas emissions from electrical power generation in the United States: carbon capture and storage (CCS) and enhanced geothermal systems (EGS). The goal of the study is to inform sustainability science theory and energy policy deliberations by examining how social and political dynamics are shaping the struggle for resources by these two emerging, not-yet-widely commercializable socio-technical systems. This characterization of socio-technical dynamics of CCS and EGS innovation includes examining the perceived technical, environmental, and financial risks and benefits of each system, as well as the discourses and actor networks through which the competition for resources - particularly public resources - is being waged. CCS and EGS were selected for the study because they vary considerably with respect to their social, technical, and environmental implications and risks, are unproven at scale and uncertain with respect to cost, feasibility, and life-cycle environmental impacts. By assessing the two technologies in parallel, the study highlights important social and political dimensions of energy technology innovation in order to inform theory and suggest new approaches to policy analysis.

  17. Cranial nerve assessment in cavernous sinus tumors with contrast-enhanced 3D fast-imaging employing steady-state acquisition MR imaging

    International Nuclear Information System (INIS)

    The purpose of this study is to apply contrast-enhanced 3D fast-imaging employing steady-state acquisition (3D-FIESTA) imaging to the evaluation of cranial nerves (CN) in patients with cavernous sinus tumors. Contrast-enhanced 3D-FIESTA images were acquired from ten patients with cavernous sinus tumors with a 3-T unit. In all cases, the trigeminal nerve with tumor involvement was easily identified in the cavernous portions. Although oculomotor and abducens nerves were clearly visualized against the tumor area with intense contrast enhancement, they were hardly identifiable within the area lacking contrast enhancement. The trochlear nerve was visualized in part, but not delineated as a linear structure outside of the lesion. Contrast-enhanced 3D-FIESTA can be useful in the assessment of cranial nerves in and around the cavernous sinus with tumor involvement. (orig.)

  18. Cranial nerve assessment in cavernous sinus tumors with contrast-enhanced 3D fast-imaging employing steady-state acquisition MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Amemiya, Shiori; Aoki, Shigeki; Ohtomo, Kuni [University of Tokyo, Department of Radiology, Graduate School of Medicine, Bunkyo-ku, Tokyo (Japan)

    2009-07-15

    The purpose of this study is to apply contrast-enhanced 3D fast-imaging employing steady-state acquisition (3D-FIESTA) imaging to the evaluation of cranial nerves (CN) in patients with cavernous sinus tumors. Contrast-enhanced 3D-FIESTA images were acquired from ten patients with cavernous sinus tumors with a 3-T unit. In all cases, the trigeminal nerve with tumor involvement was easily identified in the cavernous portions. Although oculomotor and abducens nerves were clearly visualized against the tumor area with intense contrast enhancement, they were hardly identifiable within the area lacking contrast enhancement. The trochlear nerve was visualized in part, but not delineated as a linear structure outside of the lesion. Contrast-enhanced 3D-FIESTA can be useful in the assessment of cranial nerves in and around the cavernous sinus with tumor involvement. (orig.)

  19. Local and Global Impacts of Carbon Capture and Storage Combined with Enhanced Oil Recovery in Four Depleted Oil Fields, Kern County, California

    Science.gov (United States)

    Gillespie, J.; Jordan, P. D.; Goodell, J. A.; Harrington, K.; Jameson, S.

    2015-12-01

    Depleted oil reservoirs are attractive targets for geologic carbon storage (GCS) because they possess proven trapping mechanisms and large amounts of data pertaining to production and reservoir geometry. In addition, CO2 enhanced oil recovery (EOR) can improve recovery of the remaining oil at recovery factors of 6 to 20% of original oil in place in appropriate reservoirs. CO2 EOR increases the attractiveness of depleted oil and gas reservoirs as a starting point for CCS because the CO2 becomes a commodity that can be purchased by field operators for EOR purposes thereby offsetting the costs of CO2 capture at the power plant. In California, Kern County contains the largest oil reservoirs and produces 76% of California's oil. Most of the production at depths suitable for CCS combined with CO2 EOR comes from three reservoirs: the Vedder and Temblor formations and the Stevens Sandstone of the Monterey Formation. These formations were evaluated for GCS and CO2 EOR potential at the North and South Coles Levee (Stevens Sandstone), Greeley (Vedder) and McKittrick (Temblor) fields. CO2 EOR could be expected to produce an additional 150 million bbls of oil. The total storage space created by pre- and post-EOR fluid production for all three reservoirs is approximately 104 million metric tons (MMT). Large fixed sources in California produce 156 MMT/yr of CO2, and sources in Kern County produce 26 MMT/yr (WESTCARB, 2012). Therefore, the fields could store about four years of local large fixed source emissions and about two thirds of statewide emissions. However, from a global perspective, burning the additional oil produced by CO2 EOR would generate an additional 65 MMT of CO2 if not captured. This would result in a net reduction of greenhouse gas of only 39 MMT rather than the full 104 MMT. If the water produced along with the oil recovered during CO2 EOR operations is not reinjected into the reservoir, the storage space could be much higher.

  20. Neutron capture therapy of intracerebral melanoma: enhanced survival and cure after blood-brain barrier opening to improve delivery of boronophenylalanine

    International Nuclear Information System (INIS)

    Purpose: Multicentric cerebral metastases of melanoma represent an important clinical problem for which there currently is no satisfactory treatment. We previously developed a model for melanoma metastatic to the brain employing nude rats bearing intracerebral implants of the human MRA27 melanoma. The purpose of the present study was to determine if the efficacy of boron neutron capture therapy (BNCT) could be improved by either Cereport (RMP-7) mediated modulation of blood-brain barrier (BBB) permeability or hyperosmotic mannitol-induced BBB disruption using boronophenylalanine (BPA) as the capture agent. Methods and Materials: Biodistribution studies were carried out at 0.5, 2.5, and 4 h after intracarotid administration of Cereport (1.5 μg/kg) and intracarotid or i.v. administration of BPA (500 mg/kg). Peak tumor boron concentrations (65.4 μg/g) and the best composite tumor:brain (6.1:1) and tumor:blood (6.3:1) ratios were observed at 2.5 h after intracarotid administration. BNCT was initiated at the Brookhaven Medical Research Reactor 13-14 days after intracerebral implantation of 106 MRA27 cells. Results: Untreated control rats had a median survival time (MeST) of 22 days and for irradiated controls, it was 30 days. Rats that received i.v. or intracarotid BPA without Cereport followed by BNCT 2.5 h later had MeSTs of 41 days and 57 days, respectively, with 20% long-term survivors (>180 days) in the latter group. Rats that received intracarotid BPA with Cereport had an MeST of 86 days with 36% long-term survivors, which was very close to that of rats that had hyperosmotic mannitol-induced disruption of the BBB (85 days with 25% long-term survivors). When these two groups were combined, and survival times were compared, using the Wilcoxon rank sum test, to those of rats that received intracarotid BPA without blood-brain barrier disruption, these differences were significant at the level p=0.01. Conclusions: Our data show that optimizing the delivery of BPA by

  1. Microdosimetry for Boron Neutron Capture Therapy

    International Nuclear Information System (INIS)

    The specific aims of the research proposal were as follows: (1) To design and construct small volume tissue equivalent proportional counters for the dosimetry and microdosimetry of high intensity thermal and epithermal neutron beams used in BNCT, and of modified fast neutron beams designed for boron neutron capture enhanced fast neutron therapy (BNCEFNT). (2) To develop analytical methods for estimating the biological effectiveness of the absorbed dose in BNCT and BNCEFNT based on the measured microdosimetric spectra. (3) To develop an analytical framework for comparing the biological effectiveness of different epithermal neutron beams used in BNCT and BNCEFNT, based on correlated sets of measured microdosimetric spectra and radiobiological data. Specific aims (1) and (2) were achieved in their entirety and are comprehensively documented in Jay Burmeister's Ph.D. dissertation entitled ''Specification of physical and biologically effective absorbed dose in radiation therapies utilizing the boron neutron capture reaction'' (Wayne State University, 1999). Specific aim (3) proved difficult to accomplish because of a lack of sufficient radiobiological data

  2. Chemical and Biological Catalytic Enhancement of Weathering of Silicate Minerals and industrial wastes as a Novel Carbon Capture and Storage Technology

    Science.gov (United States)

    Park, A. H. A.

    2014-12-01

    Increasing concentration of CO2 in the atmosphere is attributed to rising consumption of fossil fuels around the world. The development of solutions to reduce CO2 emissions to the atmosphere is one of the most urgent needs of today's society. One of the most stable and long-term solutions for storing CO2 is via carbon mineralization, where minerals containing metal oxides of Ca or Mg are reacted with CO2 to produce thermodynamically stable Ca- and Mg-carbonates that are insoluble in water. Carbon mineralization can be carried out in-situ or ex-situ. In the case of in-situ mineralization, the degree of carbonation is thought to be limited by both mineral dissolution and carbonate precipitation reaction kinetics, and must be well understood to predict the ultimate fate of CO2 within geological reservoirs. While the kinetics of in-situ mineral trapping via carbonation is naturally slow, it can be enhanced at high temperature and high partial pressure of CO2. The addition of weak organic acids produced from food waste has also been shown to enhance mineral weathering kinetics. In the case of the ex-situ carbon mineralization, the role of these ligand-bearing organic acids can be further amplified for silicate mineral dissolution. Unfortunately, high mineral dissolution rates often lead to the formation of a silica-rich passivation layer on the surface of silicate minerals. Thus, the use of novel solvent mixture that allows chemically catalyzed removal of this passivation layer during enhanced Mg-leaching surface reaction has been proposed and demonstrated. Furthermore, an engineered biological catalyst, carbonic anhydrase, has been developed and evaluated to accelerate the hydration of CO2, which is another potentially rate-limiting step of the carbonation reaction. The development of these novel catalytic reaction schemes has significantly improved the overall efficiency and sustainability of in-situ and ex-situ mineral carbonation technologies and allowed direct

  3. Reactivity of dolomite in water-saturated supercritical carbon dioxide: Significance for carbon capture and storage and for enhanced oil and gas recovery

    International Nuclear Information System (INIS)

    Highlights: ► Dolomite reactivity with wet and dry supercritical CO2 were evaluated. ► Dolomite does not react with dry CO2. ► H2O-saturated supercritical CO2 dissolves dolomite and precipitates carbonate mineral. ► Temperature/reaction time control morphology and extent of carbonate mineralization. ► Reaction with wet CO2 may impact trapping, caprock integrity, and CCS/EOR injectivity. - Abstract: Carbon dioxide injection in porous reservoirs is the basis for carbon capture and storage, enhanced oil and gas recovery. Injected carbon dioxide is stored at multiple scales in porous media, from the pore-level as a residual phase to large scales as macroscopic accumulations by the injection site, under the caprock and at reservoir internal capillary pressure barriers. These carbon dioxide saturation zones create regions across which the full spectrum of mutual CO2–H2O solubility may occur. Most studies assume that geochemical reaction is restricted to rocks and carbon dioxide-saturated formation waters, but this paradigm ignores injection of anhydrous carbon dioxide against brine and water-alternating-gas flooding for enhanced oil recovery. A series of laboratory experiments was performed to evaluate the reactivity of the common reservoir mineral dolomite with water-saturated supercritical carbon dioxide. Experiments were conducted at reservoir conditions (55 and 110 °C, 25 MPa) and elevated temperature (220 °C, 25 MPa) for approximately 96 and 164 h (4 and 7 days). Dolomite dissolves and new carbonate mineral precipitates by reaction with water-saturated supercritical carbon dioxide. Dolomite does not react with anhydrous supercritical carbon dioxide. Temperature and reaction time control the composition, morphology, and extent of formation of new carbonate minerals. Mineral dissolution and re-precipitation due to reaction with water-saturated carbon dioxide may affect the contact line between phases, the carbon dioxide contact angle, and the relative

  4. Life-cycle Assessment of Carbon Dioxide Capture for Enhanced Oil Recovery%为强化石油回采捕集CO2的全周期评估

    Institute of Scientific and Technical Information of China (English)

    E.G Hertwich; M.Aaberg; B.Singh; A.H.Strφmman

    2008-01-01

    The development and deployment of Carbon dioxide Capture and Storage (CCS) technology is a cornerstone of the Norwegian government's climate strategy. A number of projects are currently evaluated/planned along the Norwegian West Coast, one at Tjeldbergodden. CO2 from this project will be utilized in part for enhanced oil recovery in the Halten oil field, in the Norwegian Sea. We study a potential design of such a system. A combined cycle power plant with a gross power output of 832 MW is combined with CO2 capture plant based on a post-combustion capture using amines as a solvent. The captured CO2 is used for enhanced oil recovery (EOR). We employ a hybrid life-cycle assessment (LCA) method to assess the environmental impacts of the system. The study focuses on the modifications and operations of the platform during EOR. We allocate the impacts connected to the capture of CO2 to electricity production, and the impacts connected to the transport and storage of CO2 to the oil produced. Our study shows a substantial reduction of the greenhouse gas emissions from power production by 80% to 75g·(kW·h)-1. It also indicates a reduction of the emissions associated with oil production per unit oil produced, mostly due to the increased oil production. Reductions are especially significant if the additional power demand due to EOR leads to power supply from the land.

  5. Real-time fast inverse dose optimization for image guided adaptive radiation therapy-Enhancements to fast inverse dose optimization (FIDO)

    International Nuclear Information System (INIS)

    A fast, accurate and stable optimization algorithm is very important for inverse planning of intensity-modulated radiation therapy (IMRT), and for implementing dose-adaptive radiotherapy in the future. Conventional numerical search algorithms with positive beam weight constraints generally require numerous iterations and may produce suboptimal dose results due to trapping in local minima regions of the objective function landscape. A direct solution of the inverse problem using conventional quadratic objective functions without positive beam constraints is more efficient but it will result in unrealistic negative beam weights. We review here a direct solution of the inverse problem that is efficient and does not yield unphysical negative beam weights. In fast inverse dose optimization (FIDO) method the objective function for the optimization of a large number of beamlets is reformulated such that the optimization problem is reducible to a linear set of equations. The optimal set of intensities is then found through a matrix inversion, and negative beamlet intensities are avoided without the need for externally imposed ad hoc conditions. In its original version [S. P. Goldman, J. Z. Chen, and J. J. Battista, in Proceedings of the XIVth International Conference on the Use of Computers in Radiation Therapy, 2004, pp. 112-115; S. P. Goldman, J. Z. Chen, and J. J. Battista, Med. Phys. 32, 3007 (2005)], FIDO was tested on single two-dimensional computed tomography (CT) slices with sharp KERMA beams without scatter, in order to establish a proof of concept which demonstrated that FIDO could be a viable method for the optimization of cancer treatment plans. In this paper we introduce the latest advancements in FIDO that now include not only its application to three-dimensional volumes irradiated by beams with full scatter but include as well a complete implementation of clinical dose-volume constraints including maximum and minimum dose as well as equivalent uniform dose

  6. Integrated Health Monitoring and Fast on-Line Actuator Reconfiguration Enhancement (IHM-FLARE) System for Air Vehicles Project

    Data.gov (United States)

    National Aeronautics and Space Administration — SSCI proposes to develop innovative algorithms for the integration of Health Monitoring (HM) subsystem with the existing FLARE (Fast on-Line Actuator...

  7. Proposal for enhanced spatial resolution and efficiency of a fast-neutron scintillator detector by use of a parabolic mirror

    International Nuclear Information System (INIS)

    The limitation on the detector efficiency due to the required spatial resolution of a fast-neutron imaging system is known as the detector problem. Here, this problem is described and a proposal for a novel fast-neutron imaging system is given to overcome this problem. The novelty is to replace the standard flat mirror in an imaging system by a parabolic mirror with its focal point at the fast-neutron source position. The spatial resolution will only be limited by the intrinsic resolution of the scintillator of the order of 0.06 mm. The intrinsic fast-neutron detection efficiency can be increased to about 20-30% without loss of spatial resolution

  8. The role of Gd-enhanced three-dimensional MRI fast low-angle shot (FLASH) in the evaluation of symptomatic lumbosacral nerve roots

    Energy Technology Data Exchange (ETDEWEB)

    Kikkawa, Ichiro; Sugimoto, Hideharu; Saita, Kazuo; Ookami, Hitoshi; Nakama, Sueo; Hoshino, Yuichi [Jichi Medical School, Minamikawachi, Tochigi (Japan)

    2001-07-01

    In the field of lumbar spine disorders, three-dimensional (3-D) magnetic resonance imaging (MRI) can clearly depict a lumbar nerve root from the distal region to the dorsal root ganglion. In this study, we used a gadoliniumdiethylenetriaminepentaacetic acid (Gd-DTPA) enhanced-three-dimensional (3-D) fast low-angle shot (FLASH) sequence when examining lumbosacral disorders. The subjects were 33 patients (14 men and 19 women) in whom lumbosacral neural compression had been diagnosed clinically. Twenty-one patients had lumbar disc herniation, 11 had lumbar spinal stenosis, and 1 had lumbar radiculopathy caused by rheumatoid arthritis. Five subjects with low back pain were also studied as a control group. In all patients and in all 5 of the controls, the dorsal root ganglion of every root was enhanced clearly. There was no root enhancement in the 5 controls. Enhancement of the symptomatic nerve roots, caused by compression, was found in 11 of the 33 patients. All 11 patients had rediculopathy, and muscle weakness was more frequent in patients with enhanced nerve roots than in those without enhancement. There was no enhancement of the cauda equina, even in the patients with cauda syndrome. The enhancement effect may reflect some pathological condition of the compressed nerve root and needs to be studied further. (author)

  9. The role of Gd-enhanced three-dimensional MRI fast low-angle shot (FLASH) in the evaluation of symptomatic lumbosacral nerve roots

    International Nuclear Information System (INIS)

    In the field of lumbar spine disorders, three-dimensional (3-D) magnetic resonance imaging (MRI) can clearly depict a lumbar nerve root from the distal region to the dorsal root ganglion. In this study, we used a gadoliniumdiethylenetriaminepentaacetic acid (Gd-DTPA) enhanced-three-dimensional (3-D) fast low-angle shot (FLASH) sequence when examining lumbosacral disorders. The subjects were 33 patients (14 men and 19 women) in whom lumbosacral neural compression had been diagnosed clinically. Twenty-one patients had lumbar disc herniation, 11 had lumbar spinal stenosis, and 1 had lumbar radiculopathy caused by rheumatoid arthritis. Five subjects with low back pain were also studied as a control group. In all patients and in all 5 of the controls, the dorsal root ganglion of every root was enhanced clearly. There was no root enhancement in the 5 controls. Enhancement of the symptomatic nerve roots, caused by compression, was found in 11 of the 33 patients. All 11 patients had rediculopathy, and muscle weakness was more frequent in patients with enhanced nerve roots than in those without enhancement. There was no enhancement of the cauda equina, even in the patients with cauda syndrome. The enhancement effect may reflect some pathological condition of the compressed nerve root and needs to be studied further. (author)

  10. Differentiation between benign and malignant colon tumors using fast dynamic gadolinium-enhanced MR colonography; a feasibility study

    DEFF Research Database (Denmark)

    Achiam, M P; Andersen, L P H; Klein, M; Løgager, Vibeke Berg; Chabanova, E; Thomsen, H S; Rosenberg, J

    2010-01-01

    Colorectal cancer will present itself as a bowel obstruction in 16-23% of all cases. However, not all obstructing tumors are malignant and the differentiation between a benign and a malignant tumor can be difficult. The purpose of our study was to determine whether fast dynamic gadolinium...

  11. Dopamine D4 receptor activation increases hippocampal gamma oscillations by enhancing synchronization of fast-spiking interneurons.

    Directory of Open Access Journals (Sweden)

    Richard Andersson

    Full Text Available BACKGROUND: Gamma oscillations are electric activity patterns of the mammalian brain hypothesized to serve attention, sensory perception, working memory and memory encoding. They are disrupted or altered in schizophrenic patients with associated cognitive deficits, which persist in spite of treatment with antipsychotics. Because cognitive symptoms are a core feature of schizophrenia it is relevant to explore signaling pathways that potentially regulate gamma oscillations. Dopamine has been reported to decrease gamma oscillation power via D1-like receptors. Based on the expression pattern of D4 receptors (D4R in hippocampus, and pharmacological effects of D4R ligands in animals, we hypothesize that they are in a position to regulate gamma oscillations as well. METHODOLOGY/PRINCIPAL FINDINGS: To address this hypothesis we use rat hippocampal slices and kainate-induced gamma oscillations. Local field potential recordings as well as intracellular recordings of pyramidal cells, fast-spiking and non-fast-spiking interneurons were carried out. We show that D4R activation with the selective ligand PD168077 increases gamma oscillation power, which can be blocked by the D4R-specific antagonist L745,870 as well as by the antipsychotic drug Clozapine. Pyramidal cells did not exhibit changes in excitatory or inhibitory synaptic current amplitudes, but inhibitory currents became more coherent with the oscillations after application of PD168077. Fast-spiking, but not non-fast spiking, interneurons, increase their action potential phase-coupling and coherence with regard to ongoing gamma oscillations in response to D4R activation. Among several possible mechanisms we found that the NMDA receptor antagonist AP5 also blocks the D4R mediated increase in gamma oscillation power. CONCLUSIONS/SIGNIFICANCE: We conclude that D4R activation affects fast-spiking interneuron synchronization and thereby increases gamma power by an NMDA receptor-dependent mechanism. This

  12. Quantum-Noise-Limited Sensitivity-Enhancement of a Passive Optical Cavity by a Fast-Light Medium

    Science.gov (United States)

    Smith, David D.; Luckay, H. A.; Chang, Hongrok; Myneni, Krishna

    2016-01-01

    We demonstrate for a passive optical cavity containing an intracavity dispersive atomic medium, the increase in scale factor near the critical anomalous dispersion is not cancelled by mode broadening or attenuation, resulting in an overall increase in the predicted quantum-noiselimited sensitivity. Enhancements of over two orders of magnitude are measured in the scale factor, which translates to greater than an order-of-magnitude enhancement in the predicted quantumnoise- limited measurement precision, by temperature tuning a low-pressure vapor of noninteracting atoms in a low-finesse cavity close to the critical anomalous dispersion condition. The predicted enhancement in sensitivity is confirmed through Monte-Carlo numerical simulations.

  13. A study on assessment of the effectiveness of fast reactor system for enhancing the national energy security in the electricity sector

    International Nuclear Information System (INIS)

    Energy security, in 21st century, draws a most noticeable attention in most countries worldwide because the national sustainable development and security depend largely on the level of the energy security. Lack of national conventional energy resources and instability of the energy supply market become a driving element for many countries to consider the nuclear energy as the essential instrument for enhancing the national energy security. In this study, indicators for measuring the level of energy security in the electric power sector were developed. These indicators were then used to assess the effectiveness of fast reactor system for enhancing the national energy security with respect to a diversification of the energy markets and a vulnerability to the economic disruption. This study examined the four schemes of the electric power system deploying different nuclear fuel cycle technologies in Korean electricity sector. As the results, the closed fuel cycle schemes are turned out to be a fuel cycle scheme having better contributions to the diversification of the fuel supply than the once-through fuel cycle scheme. The study further shows that the completely closed fuel cycle with the spent fuel recycling in fast reactors enhances the national energy security to the maximum extent compared to all other fuel cycle schemes considered in the study. Since the completely closed fuel cycle technology with fast reactor system is hardly affected by the uranium price changes, this scheme is evaluated as the most favorable scheme with respect to ensuring the stable profit of utilities and contributing to the stabilization of the electricity tariff. However, the study implies that to choose 'scheme c'(TRU burning in fast reactors) could contribute more to the improvement of electric power system stability than to choose 'scheme b'(partial recycle of Pu in thermal reactors) in terms of near-term fuel cycle policy establishment. The indicators developed in this study can be

  14. Enhanced high-frequency membrane potential fluctuations control spike output in striatal fast-spiking interneurones in vivo.

    Science.gov (United States)

    Schulz, Jan M; Pitcher, Toni L; Savanthrapadian, Shakuntala; Wickens, Jeffery R; Oswald, Manfred J; Reynolds, John N J

    2011-09-01

    Fast-spiking interneurones (FSIs) constitute a prominent part of the inhibitory microcircuitry of the striatum; however, little is known about their recruitment by synaptic inputs in vivo. Here, we report that, in contrast to cholinergic interneurones (CINs), FSIs (n = 9) recorded in urethane-anaesthetized rats exhibit Down-to-Up state transitions very similar to spiny projection neurones (SPNs). Compared to SPNs, the FSI Up state membrane potential was noisier and power spectra exhibited significantly larger power at frequencies in the gamma range (55-95 Hz). The membrane potential exhibited short and steep trajectories preceding spontaneous spike discharge, suggesting that fast input components controlled spike output in FSIs. Spontaneous spike data contained a high proportion (43.6 ± 32.8%) of small inter-spike intervals (ISIs) of ISIs (<30 ms; 4.3 ± 6.4%, n = 8). The gamma frequency content did not change in CINs (n = 8). These results indicate that FSIs are uniquely responsive to high-frequency input sequences. By controlling the spike output of SPNs, FSIs could serve gating of top-down signals and long-range synchronisation of gamma-oscillations during behaviour. PMID:21746788

  15. Optimization of MALDI-TOF MS Detection for Enhanced Sensitivity of Affinity-Captured Proteins Spanning a 100 kDa Mass Range

    OpenAIRE

    Gatlin-Bunai, Christine L.; Lisa H. Cazares; Cooke, William E.; Semmes, Oliver J.; Malyarenko, Dariya I.

    2007-01-01

    Analysis of complex biological samples by MALDI-TOF mass spectrometry has been generally limited to the detection of low-mass protein (or protein fragment) peaks. We have extended the mass range of MALDI-TOF high-sensitivity detection by an order of magnitude through the combined optimization of instrument parameters, data processing, and sample preparation procedures for affinity capture. WCX, C3, and IMAC magnetic beads were determined to be complementary and most favorable for broad mass r...

  16. Quantum-Noise-Limited Sensitivity-Enhancement of a Passive Optical Cavity by a Fast-Light Medium

    CERN Document Server

    Smith, David D; Chang, Hongrok; Myneni, Krishna

    2016-01-01

    We demonstrate for a passive optical cavity containing an intracavity dispersive atomic medium, the increase in scale factor near the critical anomalous dispersion is not cancelled by mode broadening or attenuation, resulting in an overall increase in the predicted quantum-noise-limited sensitivity. Enhancements of over two orders of magnitude are measured in the scale factor, which translates to greater than an order-of-magnitude enhancement in the predicted quantum-noise-limited measurement precision, by temperature tuning a low-pressure vapor of non-interacting atoms in a low-finesse cavity close to the critical anomalous dispersion condition. The predicted enhancement in sensitivity is confirmed through Monte-Carlo numerical simulations.

  17. Enhanced photoacoustic gas analyser response time and impact on accuracy at fast ventilation rates during multiple breath washout.

    Directory of Open Access Journals (Sweden)

    Alex Horsley

    Full Text Available BACKGROUND: The Innocor device contains a highly sensitive photoacoustic gas analyser that has been used to perform multiple breath washout (MBW measurements using very low concentrations of the tracer gas SF6. Use in smaller subjects has been restricted by the requirement for a gas analyser response time of <100 ms, in order to ensure accurate estimation of lung volumes at rapid ventilation rates. METHODS: A series of previously reported and novel enhancements were made to the gas analyser to produce a clinically practical system with a reduced response time. An enhanced lung model system, capable of delivering highly accurate ventilation rates and volumes, was used to assess in vitro accuracy of functional residual capacity (FRC volume calculation and the effects of flow and gas signal alignment on this. RESULTS: 10-90% rise time was reduced from 154 to 88 ms. In an adult/child lung model, accuracy of volume calculation was -0.9 to 2.9% for all measurements, including those with ventilation rate of 30/min and FRC of 0.5 L; for the un-enhanced system, accuracy deteriorated at higher ventilation rates and smaller FRC. In a separate smaller lung model (ventilation rate 60/min, FRC 250 ml, tidal volume 100 ml, mean accuracy of FRC measurement for the enhanced system was minus 0.95% (range -3.8 to 2.0%. Error sensitivity to flow and gas signal alignment was increased by ventilation rate, smaller FRC and slower analyser response time. CONCLUSION: The Innocor analyser can be enhanced to reliably generate highly accurate FRC measurements down at volumes as low as those simulating infant lung settings. Signal alignment is a critical factor. With these enhancements, the Innocor analyser exceeds key technical component recommendations for MBW apparatus.

  18. Enhancement of image quality with a fast iterative scatter and beam hardening correction method for kV CBCT

    Energy Technology Data Exchange (ETDEWEB)

    Reitz, Irmtraud; Hesse, Bernd-Michael; Nill, Simeon; Tuecking, Thomas; Oelfke, Uwe [DKFZ, Heidelberg (Germany)

    2009-07-01

    The problem of the enormous amount of scattered radiation in kV CBCT (kilo voltage cone beam computer tomography) is addressed. Scatter causes undesirable streak- and cup-artifacts and results in a quantitative inaccuracy of reconstructed CT numbers, so that an accurate dose calculation might be impossible. Image contrast is also significantly reduced. Therefore we checked whether an appropriate implementation of the fast iterative scatter correction algorithm we have developed for MV (mega voltage) CBCT reduces the scatter contribution in a kV CBCT as well. This scatter correction method is based on a superposition of pre-calculated Monte Carlo generated pencil beam scatter kernels. The algorithm requires only a system calibration by measuring homogeneous slab phantoms with known water-equivalent thicknesses. In this study we compare scatter corrected CBCT images of several phantoms to the fan beam CT images acquired with a reduced cone angle (a slice-thickness of 14 mm in the isocenter) at the same system. Additional measurements at a different CBCT system were made (different energy spectrum and phantom-to-detector distance) and a first order approach of a fast beam hardening correction will be introduced. The observed, image quality of the scatter corrected CBCT images is comparable concerning resolution, noise and contrast-to-noise ratio to the images acquired in fan beam geometry. Compared to the CBCT without any corrections the contrast of the contrast-and-resolution phantom with scatter correction and additional beam hardening correction is improved by a factor of about 1.5. The reconstructed attenuation coefficients and the CT numbers of the scatter corrected CBCT images are close to the values of the images acquired in fan beam geometry for the most pronounced tissue types. Only for extreme dense tissue types like cortical bone we see a difference in CT numbers of 5.2%, which can be improved to 4.4% with the additional beam hardening correction. Cupping

  19. Atomic thin titania nanosheet-coupled reduced graphene oxide 2D heterostructures for enhanced photocatalytic activity and fast lithium storage

    Science.gov (United States)

    Li, Dong Jun; Huang, Zhegang; Hwang, Tae Hoon; Narayan, Rekha; Choi, Jang Wook; Kim, Sang Ouk

    2016-03-01

    Realizing practical high performance materials and devices using the properties of 2D materials is of key research interest in the materials science field. In particular, building well-defined heterostructures using more than two different 2D components in a rational way is highly desirable. In this paper, a 2D heterostructure consisting of atomic thin titania nanosheets densely grown on reduced graphene oxide surface is successfully prepared through incorporating polymer functionalized graphene oxide into the novel TiO2 nanosheets synthesis scheme. As a result of the synergistic combination of a highly accessible surface area and abundant interface, which can modulate the physicochemical properties, the resultant heterostructure can be used in high efficiency visible light photocatalysis as well as fast energy storage with a long lifecycle. [Figure not available: see fulltext.

  20. FAST DISSOLVING TABLETS: AN UPDATE

    OpenAIRE

    Darna Bikshapathi; Kandikonda Saikrishna; Uppuluru Ashok Kumar; Gade Sabitha; Bhupathi Saikumar

    2011-01-01

    Fast dissolving tablets are dissolving rapidly in the saliva without the need for water. Some tablets are designed to dissolve in saliva remarkably fast, within a few seconds, and are true fast-dissolving tablets. Other ingredients to enhance the rate of tablet disintegration in the oral cavity, and are more appropriately termed fast-disintegrating tablets, as they may take up to a minute to completely disintegrate. Fast or mouth dissolving tablets have been formulated for pediatric, geriatri...

  1. FAST TRACK COMMUNICATION: Enhanced dc conductivity of low volume-fraction nano-particulate suspensions in silicone and perfluorinated oils

    Science.gov (United States)

    Wilson, S. A.; Libor, Z.; Skordos, A. A.; Zhang, Q.

    2009-03-01

    The dc conductivities of several different types of nanoparticles (nickel, barium titanate and magnetite) suspended in both silicone and perfluorinated oils have been measured and contrasted. Enhanced dc conductivity through interaction between the particles and the fluid has been demonstrated, even at quite moderate fields, and different types of nanoparticles have been shown to exhibit different behavioural trends. Whilst the dc enhancement is partly related to the concentration (or spatial arrangement) of the particles as expected, there is clear evidence that energy-activated (electric field activated) processes also play a major role. It can be said that effective-medium theories based solely on the electrical properties and volume fractions of the component materials have limited applicability when assessing the dc conductivities of these nanoparticle-fluid combinations at low volume fractions.

  2. Towards modeling and validation enhancements of the PSI MCNPX fast neutron fluence computational scheme based on recent PWR experimental data

    International Nuclear Information System (INIS)

    Highlights: • V&V studies with CASMO/SIMULATE/MCNPX computation scheme are described. • Fixed-source modeling is used for PWR ex-core Monte Carlo neutron transport. • The reference data includes activity measurements and fluence estimations. • Adjusting the calculation models for the specific validation data sets is discussed. • Obtained results and findings of associated sensitivity studies are reported. - Abstract: At the Paul Scherrer Institute (PSI), a computational scheme aimed at high fidelity fast neutron fluence estimations for Light-Water-Reactors (LWRs) was in previous years developed. In this scheme, the neutron transport calculations are performed with the stochastic Monte Carlo N-Particle Transport Code MCNPX using as basis a three-dimensional pin-level volumetric source obtained from validated deterministic CASMO/SIMULATE models. While first validation studies confirmed a satisfactory performance, the strategy is to continually add new validation cases in order to achieve an enlarged and comprehensive qualification basis that also integrates latest advances in methods and/or nuclear data. Thereby, new sets of experimental data from a Swiss operating pressurized water reactor plant that became available recently were adopted for a further validation of the scheme. The first set consists of 54Mn and 93mNb activity measurements from so-called gradient probes located at an elevation corresponding to the top end of active fuel and increasing thereby the computational challenges because of very strong axial flux gradients. The second set consists of fluence estimates derived from 54Mn and 93mNb activity measurements of scraping samples extracted from the reactor pressure vessel. All dosimeters have been analyzed after the 27th cycle of operation of the reactor, providing thereby an opportunity to assess the computational methodology for modern fuel management schemes. This paper presents the validation study of the PSI fast neutron fluence scheme

  3. Enhanced Dopamine Release by Dopamine Transport Inhibitors Described by a Restricted Diffusion Model and Fast-Scan Cyclic Voltammetry.

    Science.gov (United States)

    Hoffman, Alexander F; Spivak, Charles E; Lupica, Carl R

    2016-06-15

    Fast-scan cyclic voltammetry (FSCV) using carbon fiber electrodes is widely used to rapidly monitor changes in dopamine (DA) levels in vitro and in vivo. Current analytical approaches utilize parameters such as peak oxidation current amplitude and decay times to estimate release and uptake processes, respectively. However, peak amplitude changes are often observed with uptake inhibitors, thereby confounding the interpretation of these parameters. To overcome this limitation, we demonstrate that a simple five-parameter, two-compartment model mathematically describes DA signals as a balance of release (r/ke) and uptake (ku), summed with adsorption (kads and kdes) of DA to the carbon electrode surface. Using nonlinear regression, we demonstrate that our model precisely describes measured DA signals obtained in brain slice recordings. The parameters extracted from these curves were then validated using pharmacological manipulations that selectively alter vesicular release or DA transporter (DAT)-mediated uptake. Manipulation of DA release through altering the Ca(2+)/Mg(2+) ratio or adding tetrodotoxin reduced the release parameter with no effect on the uptake parameter. DAT inhibitors methylenedioxypyrovalerone, cocaine, and nomifensine significantly reduced uptake and increased vesicular DA release. In contrast, a low concentration of amphetamine reduced uptake but had no effect on DA release. Finally, the kappa opioid receptor agonist U50,488 significantly reduced vesicular DA release but had no effect on uptake. Together, these data demonstrate a novel analytical approach to distinguish the effects of manipulations on DA release or uptake that can be used to interpret FSCV data. PMID:27018734

  4. Impact of Thorium Capture Cross Section Uncertainty on the Thorium Utilized ADS Reactivity Calculation

    Directory of Open Access Journals (Sweden)

    Thanh Mai Vu

    2014-01-01

    Full Text Available Recently, the researches on fast neutron spectrum system utilized thorium fuel are widely conducted. However, the recent thorium cross section libraries are limited compared to uranium cross section libraries. The impact of thorium cross section uncertainty on thorium fuel utilized accelerator driven system (ADS reactivity calculation is estimated in this study. The uncertainty of the keff caused by 232Th capture cross section of JENDL-4.0 is about 1.3%. The uncertainty of JENDL-4.0 is needed to be enhanced to provide more reliable results on reactivity calculation for the fast system. The impact of uncertainty of  232Th capture cross section of ENDF/B-VII is small (0.1%. Therefore, it will cause no significant impact of the thorium cross section library on the thorium utilized ADS design calculation.

  5. Booster immunization with a partially purified citrus tristeza virus (CTV) preparation after priming with recombinant CTV coat protein enhances the binding capacity of capture antibodies by ELISA.

    Science.gov (United States)

    Bar-Joseph, M; Filatov, V; Gofman, R; Guang, Y; Hadjinicolis, A; Mawassi, M; Gootwine, E; Weisman, Y; Malkinson, M

    1997-08-01

    Groups of rabbits and young lambs were immunized subcutaneously and intramuscularly with a recombinant citrus tristeza virus (CTV) coat protein (rCTV-CP) antigen. Three weeks after primary immunization the animals were divided into two groups that were boosted either with rCTV-CP or with a partially purified preparation of CTV particles (ppCTV). Twelve and 15 days after the last injection, the animals were bled and the binding capacity of the antisera for CTV detection was examined for capture antibodies by the indirect ELISA. Considerably higher ELISA titers were obtained from animals that were boosted with ppCTV than with rCP. Boosting with partially purified native antigens after priming with recombinant antigens is expected to extend the applicability of the antisera for detecting other structural and non-structural viral antigens by trapping ELISA. PMID:9274814

  6. Fast and accurate solution for the SCUC problem in large-scale power systems using adapted binary programming and enhanced dual neural network

    International Nuclear Information System (INIS)

    Highlights: • A novel hybrid method based on decomposition of SCUC into QP and BP problems is proposed. • An adapted binary programming and an enhanced dual neural network model are applied. • The proposed EDNN is exactly convergent to the global optimal solution of QP. • An AC power flow procedure is developed for including contingency/security issues. • It is suited for large-scale systems, providing both accurate and fast solutions. - Abstract: This paper presents a novel hybrid method for solving the security constrained unit commitment (SCUC) problem. The proposed formulation requires much less computation time in comparison with other methods while assuring the accuracy of the results. Furthermore, the framework provided here allows including an accurate description of warmth-dependent startup costs, valve point effects, multiple fuel costs, forbidden zones of operation, and AC load flow bounds. To solve the nonconvex problem, an adapted binary programming method and enhanced dual neural network model are utilized as optimization tools, and a procedure for AC power flow modeling is developed for including contingency/security issues, as new contributions to earlier studies. Unlike classical SCUC methods, the proposed method allows to simultaneously solve the unit commitment problem and comply with the network limits. In addition to conventional test systems, a real-world large-scale power system with 493 units has been used to fully validate the effectiveness of the novel hybrid method proposed

  7. Ultra-fast and sensitive detection of non-typhoidal Salmonella using microwave-accelerated metal-enhanced fluorescence ("MAMEF".

    Directory of Open Access Journals (Sweden)

    Sharon M Tennant

    Full Text Available Certain serovars of Salmonella enterica subsp. enterica cause invasive disease (e.g., enteric fever, bacteremia, septicemia, meningitis, etc. in humans and constitute a global public health problem. A rapid, sensitive diagnostic test is needed to allow prompt initiation of therapy in individual patients and for measuring disease burden at the population level. An innovative and promising new rapid diagnostic technique is microwave-accelerated metal-enhanced fluorescence (MAMEF. We have adapted this assay platform to detect the chromosomal oriC locus common to all Salmonella enterica subsp. enterica serovars. We have shown efficient lysis of biologically relevant concentrations of Salmonella spp. suspended in bacteriological media using microwave-induced lysis. Following lysis and DNA release, as little as 1 CFU of Salmonella in 1 ml of medium can be detected in <30 seconds. Furthermore the assay is sensitive and specific: it can detect oriC from Salmonella serovars Typhi, Paratyphi A, Paratyphi B, Paratyphi C, Typhimurium, Enteritidis and Choleraesuis but does not detect Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Streptococcus pneumoniae, Haemophilus influenzae or Acinetobacter baumanii. We have also performed preliminary experiments using a synthetic Salmonella oriC oligonucleotide suspended in whole human blood and observed rapid detection when the sample was diluted 1:1 with PBS. These pre-clinical data encourage progress to the next step to detect Salmonella in blood (and other ordinarily sterile, clinically relevant body fluids.

  8. Fast assembling microarrays of superparamagnetic Fe3O4@Au nanoparticle clusters as reproducible substrates for surface-enhanced Raman scattering

    Science.gov (United States)

    Ye, Min; Wei, Zewen; Hu, Fei; Wang, Jianxin; Ge, Guanglu; Hu, Zhiyuan; Shao, Mingwang; Lee, Shuit-Tong; Liu, Jian

    2015-08-01

    It is currently a very active research area to develop new types of substrates which integrate various nanomaterials for surface-enhanced Raman scattering (SERS) techniques. Here we report a unique approach to prepare SERS substrates with reproducible performance. It features silicon mold-assisted magnetic assembling of superparamagnetic Fe3O4@Au nanoparticle clusters (NCs) into arrayed microstructures on a wafer scale. This approach enables the fabrication of both silicon-based and hydrogel-based substrates in a sequential manner. We have demonstrated that strong SERS signals can be harvested from these substrates due to an efficient coupling effect between Fe3O4@Au NCs, with enhancement factors >106. These substrates have been confirmed to provide reproducible SERS signals, with low variations in different locations or batches of samples. We investigate the spatial distributions of electromagnetic field enhancement around Fe3O4@Au NCs assemblies using finite-difference-time-domain (FDTD) simulations. The procedure to prepare the substrates is straightforward and fast. The silicon mold can be easily cleaned out and refilled with Fe3O4@Au NCs assisted by a magnet, therefore being re-useable for many cycles. Our approach has integrated microarray technologies and provided a platform for thousands of independently addressable SERS detection, in order to meet the requirements of a rapid, robust, and high throughput performance.It is currently a very active research area to develop new types of substrates which integrate various nanomaterials for surface-enhanced Raman scattering (SERS) techniques. Here we report a unique approach to prepare SERS substrates with reproducible performance. It features silicon mold-assisted magnetic assembling of superparamagnetic Fe3O4@Au nanoparticle clusters (NCs) into arrayed microstructures on a wafer scale. This approach enables the fabrication of both silicon-based and hydrogel-based substrates in a sequential manner. We have

  9. Diverse role of fast growing rhizobia in growth promotion and enhancement of psoralen content in Psoralea corylifolia L

    Directory of Open Access Journals (Sweden)

    Chandra Prabha

    2013-01-01

    Full Text Available Background: Psoralea corylifolia (Bakuchi, a weed, which possesses a highly potent and medicinally important compound psoralen. P. corylifolia has been widely exploited since ages for its biological potential. Materials and Methods: Fifteen root nodulating bacteria as pure culture collection (PCC were isolated from P. corylifolia in India. Further, these strains were evaluated for their effect on the psoralen content in P. corylifolia. High performance liquid chromatography (HPLC method was used for the estimation of psoralen in P. corylifolia seed extracts. The effectiveness of these rhizobial strains was assessed on the basis of screening of various plant growth promoting attributes. Results: The 16S ribosomal RNA sequencing analysis revealed the identity of two most effective rhizobial isolates PCC2 and PCC7 as Rhizobium leguminosarum and Sinorhizobium meliloti, respectively. The R. leguminosarum PCC2 (JN546144 and Ensifer meliloti PCC7 (JN546145 strains showed solubilization of insoluble inorganic phosphate, secreted indole acetic acid (IAA, produced siderophore, showed ACC deaminase activity, and were positive for nodulation and nitrogen fixing genes. Seeds of P. corylifolia were bacterized with combination of R. leguminosarum PCC2 and Ensifer meliloti PCC7 along with their individual application that resulted in enhancement of various early vegetative and late reproduction parameters of plants in two consecutive field trials in the year 2009 and 2010. The psoralen content in the seeds of P. corylifolia was observed to be increased in the field trials where the combination of rhizobial strains PCC2 and PCC7 was used (2.79% compared to control (1.91%. Conclusion: These findings indicate that rhizobial strains PCC2 and PCC7 showing good plant growth promoting attributes can be effective for increasing the psoralen content in the seeds of P. corylifolia to a certain level.

  10. CT Reconstruction from Simultaneous Projections: A Step towards Capturing CT in One Go

    CERN Document Server

    Saha, Sajib; Lambert, Andrew; Pickering, Mark

    2014-01-01

    This paper focuses on minimizing the time requirement for CT capture through innovative simultaneous x-ray capture method. The state-of-the-art CT imaging methodology captures a sequence of projections during which the internal organ movements may lead to poor reconstruction due to motion artefacts. Traditional CT scanners' minimize such effect by taking more projections than necessary. In this work we focus on an innovative CT capture method that captures projections simultaneously, promising super fast scans along with possible radiation dose reductions. While the simultaneous CT capture model has already been proposed in our earlier work 'Multi-axial CT Reconstruction from Few View Projections' (in SPIE Optical Engineering and Applications, pp. 85000A-85000A. International Society for Optics and Photonics, 2012) and 'A New Imaging Method for Real-time 3D X-ray Reconstruction' (in SPIE Medical Imaging, pp. 86685G-86685G. International Society for Optics and Photonics, 2013), in this work we enhance the mode...

  11. Deep stratosphere-to-troposphere transport (STT over SE Europe: a complex case study captured by enhanced 7Be concentrations at the surface of a low topography region

    Directory of Open Access Journals (Sweden)

    A. Ioannidou

    2005-01-01

    Full Text Available In this study we present a complex case study of a Stratosphere-to-Troposphere Transport (STT event down to the surface of a low topography region in Northern Greece, during the second fortnight of March 2000. During this event our surface station at Livadi (23°15 E/40°32 N, 850 m a.s.l., was influenced by very different synoptic systems developing over Eastern Europe, N. America and the N. Atlantic, the last one evolving to a cut-off low over France/Spain. This is the first study, to our knowledge, that presents a down to the surface STT event in the eastern Mediterranean. The intrusion is primarily captured with the use of the cosmogenic radionuclide 7Be, which increased to 9.07 mBq m-3 and 9.37 mBq m-3 on 30 and 31 March 2000, respectively. A 7Be concentration of around 8 mBq m-3 recorded during parallel measurements at Thessaloniki (20 m a.s.l. gives strong evidence that air of stratospheric origins has even gone down to sea level. A rapid increase of 10–15 ppb is also observed in the surface ozone concentration on 31 March 2000. The relative increase of both tracers is consistent with a volume fraction of stratospheric air at the surface of about 5%, but the substantial increase in 7Be flags more clearly the event. Trajectory analyses, in conjunction with the evolution of the synoptic situation described by potential vorticity maps, are used for the exact identification of the different intrusions and the attribution of each intruding parcel of stratospheric air to a certain filament of high PV. Finally, the persistency of the stratospheric layers in the troposphere is another interesting point of this case study. The vast majority of the trajectories spent 7–10 days in the troposphere before reaching the surface at Livadi station.

  12. Video Screen Capture Basics

    Science.gov (United States)

    Dunbar, Laura

    2014-01-01

    This article is an introduction to video screen capture. Basic information of two software programs, QuickTime for Mac and BlueBerry Flashback Express for PC, are also discussed. Practical applications for video screen capture are given.

  13. Evaluation of iron colloid-enhanced T2-weighted fast MR imaging of hepatocellular carcinoma. Comparison of SE, TSE and TGSE sequences

    International Nuclear Information System (INIS)

    We have applied chondroitin sulfate iron colloid (CSIC) as a contrast agent for MRI in detecting hepatocellular carcinoma (HCC) on conventional spin-echo sequences (SE). In this report, we evaluated CSIC-enhanced T2-weighted fast MR imaging of HCC. MR imaging were performed before and after i.v. administration of CSIC in 15 patients with 46 HCCs. T2-weighted SE (1800/80/2, 210 x 256 matrix), T2-weighted turbo spin-echo (TSE1800) (1800/90/5, echo train length=7, 252 x 256 matrix), TSE (3500/90/5, echo train length=7, 252 x 256 matrix) (TSE7), TSE (3500/99/5, echo train length=11, 242 x 256 matrix) (TSE11) and T2-weighted turbo-gradient spine-echo (TGSE) (4500/108/4, echo train length=33, 252 x 256 matrix) images were compared quantitatively and qualitatively. In all sequences, liver signal-to-noise ratio (SNR) was significantly decreased and lesion-to-liver contrast-to-noise ratio (CNR) was significantly increased after CSIC administration. Although decreased ratio in liver and tumor SNR caused by CSIC was smaller on TSE sequences compared with SE and TGSE, increased ratio in lesion-to-liver CNR was largest on TSE7. Either before or after i.v. administration of CSIC, the number of detectable lesions was largest on TSE7. TSE with used longer TR, TE and decreased echo factor was useful method for CSIC-enhanced abdominal MR imaging. (author)

  14. Follow-up of patients with previous treatment for coarctation of the thoracic aorta: comparison between contrast-enhanced MR angiography and fast spin-echo MR imaging

    International Nuclear Information System (INIS)

    Regular follow-up is required in patients with previous intervention for coarctation of the aorta to detect recoarctation or aneurysm formation. In this study we describe the findings encountered on routine follow-up exams and we compare the use of contrast-enhanced 3D MR angiography (CE MRA) with fast spin-echo MRI (FSE) to study the thoracic aorta after previous intervention. In 51 consecutive patients previously treated for aortic coarctation, 74 MR studies of the thoracic aorta were performed during a 2-year period using CE MRA and FSE MRI. The thoracic aorta was evaluated for abnormalities of course, caliber, shape, and pathology of side branches. The CE MRA and FSE MRI studies were evaluated side by side by consensus of two reviewers evaluating which MR technique depicted the abnormalities of the thoracic aorta the best. Of 74 exams, six clinically important abnormalities were found: four aneurysms and two restenoses. Two small pseudoaneurysms were missed on the FSE studies. Contrast-enhanced MRA was judged to visualize aortic abnormalities better than FSE (47 of 74 MR studies) especially for the transverse aortic arch, coarctation site, left subclavian artery, and aortic arch configuration. For the ascending aorta and distal descending aorta, CE MRA and FSE performed equally well. Aortic diameters measured at four levels in the first 18 MRI studies showed no significant differences in diameter when measured by FSE or CE MRA (p = not significant). Clinically important abnormalities, such as aneurysm formation and restenosis, can be present years after treatment for aortic coarctation. In the regular follow-up of these patients, CE MRA may provide additional diagnostic information compared with FSE and should be included as part of the routine exam. (orig.)

  15. Microwave-enhanced synthesis of magnetic porous covalent triazine-based framework composites for fast separation of organic dye from aqueous solution

    International Nuclear Information System (INIS)

    Graphical abstract: - Abstract: A novel type of magnetic porous carbonaceous polymeric material, CTF/Fe2O3 composite (CTF = covalent triazine-based framework), has been synthesized by a facile microwave-enhanced high-temperature ionothermal method. By selecting ZnCl2 as a reaction medium and the Lewis acid catalyst, and choosing FeCl3.6H2O as an iron oxide precursor, a series of CTF/Fe2O3 composites with different γ-Fe2O3 contents has been prepared in 60 min. The resulting samples were characterized by the X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), vibration sample magnetometer (VSM), and N2 sorption-desorption isotherms. The obtained CTF/Fe2O3 composites exhibit high surface areas (930-1149 m2 g-1), and their saturation magnetizations at 300 K vary from 1.1 to 5.9 emu g-1, depending respectively on different Fe2O3 contents (6.43-12.43 wt%) in the CTF/Fe2O3 composites. The CTF/Fe2O3 composites were applied to remove organic dye from aqueous solution by selecting methyl orange as a model molecule, and both high adsorption capacity (291 mg g-1, corresponding to 0.889 mmol g-1) and fast adsorption kinetics (kads = 4.31 m2 mg-1 min-1) were observed.

  16. Toward food analytics: fast estimation of lycopene and β-carotene content in tomatoes based on surface enhanced Raman spectroscopy (SERS).

    Science.gov (United States)

    Radu, Andreea Ioana; Ryabchykov, Oleg; Bocklitz, Thomas Wilhelm; Huebner, Uwe; Weber, Karina; Cialla-May, Dana; Popp, Jürgen

    2016-07-21

    Carotenoids are molecules that play important roles in both plant development and in the well-being of mammalian organisms. Therefore, various studies have been performed to characterize carotenoids' properties, distribution in nature and their health benefits upon ingestion. Nevertheless, there is a gap regarding a fast detection of them at the plant phase. Within this contribution we report the results obtained regarding the application of surface enhanced Raman spectroscopy (SERS) toward the differentiation of two carotenoid molecules (namely, lycopene and β-carotene) in tomato samples. To this end, an e-beam lithography (EBL) SERS-active substrate and a 488 nm excitation source were employed, and a relevant simulated matrix was prepared (by mixing the two carotenoids in defined percentages) and measured. Next, carotenoids were extracted from tomato plants and measured as well. Finally, a combination of principal component analysis and partial least squares regression (PCA-PLSR) was applied to process the data, and the obtained results were compared with HPLC measurements of the same extracts. A good agreement was obtained between the HPLC and the SERS results for most of the tomato samples. PMID:27200439

  17. Development of fast dissolving oral films containing lercanidipine HCl nanoparticles in semicrystalline polymeric matrix for enhanced dissolution and ex vivo permeation.

    Science.gov (United States)

    Chonkar, Ankita D; Rao, J Venkat; Managuli, Renuka S; Mutalik, Srinivas; Dengale, Swapnil; Jain, Prateek; Udupa, N

    2016-06-01

    Lercanidipine is a vasoselective dihydropyridine calcium antagonist, mainly used for the treatment of hypertension and angina pectoris. However, it suffers from food dependent absorption, poor solubility, low permeability and considerable first pass metabolism, resulting in highly variable and low bioavailability of 10%. Nanoparticles of lercanidipine were incorporated in fast dissolving oral films (FDO) via preparation of nanosuspension by evaporative antisolvent precipitation method. Prepared nanosuspensions were incorporated in FDO without lyophilizing or spray drying. Two nanosuspensions containing PEG 400 and TPGS 1000 as stabilizers, were selected further for incorporation in FDO. Physicochemical and mechanical properties of the optimized films were observed to be within acceptance criteria. SEM images as well as FTIR chemical images of oral films show uniform distribution of nanoparticles in polymeric matrix. The DSC and XRD results proved the poorly crystalline nature of lercanidipine. However thermal processing of film induces crystallinity in hypromellose which results in embedding of amorphous drug nanoparticles in semicrystalline polymeric matrix. Superior dissolution and permeability properties of nanoparticles were confirmed by in vitro dissolution studies and about 4.5-folds higher ex vivo drug permeation was observed from formulation through porcine buccal mucosa. This may give the clue for enhancement of bioavailability in vivo via improving orotransmucosal absorption. PMID:27063592

  18. Enhancement of reactivity in Li4SiO4-based sorbents from the nano-sized rice husk ash for high-temperature CO2 capture

    International Nuclear Information System (INIS)

    Highlights: • The Li4SiO4 sorbent from nano-sized rice husk ash was prepared and characterized. • The Aerosil and Quartz were comparably used for synthesized Li4SiO4. • The structure of sorbent was depended on the morphology of heated silicon materials. • The pretreatment sorbent showed increase in the CO2 uptake and kinetic behavior. • This promising sorbent also maintained higher capacities during the multiple cycles. - Abstract: Using the cost-effective, renewable and nano-sized of citric acid pretreatment rice husk ash (CRHA) as silicon source, high efficient Li4SiO4 (lithium orthosilicate)-based sorbents (CRHA-Li4SiO4) for high-temperature CO2 capture were prepared through the solid-state reaction at lower temperature (700 °C). Two typical raw materials (nano-structured Aerosil and crystalline Quartz powders) were used to synthesize Li4SiO4 sorbents (Aerosil-Li4SiO4 and Quartz-Li4SiO4) for comparison purposes. The phase composition behavior, surface area, and morphology of the silicon sources, heat treated raw materials and as-received Li4SiO4 sorbents were studied by analytical techniques. The CO2 adsorption capacity and adsorption–desorption performance were tested by the thermo-gravimetric analyses (CO2 atmosphere) and a fixed bed reactor, respectively. Compared with the case of its original samples, the morphology of heat treated raw materials had a greater effect on the phase composition, microstructure, special surface area and CO2 adsorption properties of their resulting sorbents. Although the calcined Quartz sample maintained the structure of micron particles, its reactivity was not enough to react completely with Li2CO3. Due to the greater reactivity of nanoparticles, Aerosil-Li4SiO4 presented pure of Li4SiO4 whereas it obtained large particles with dense morphology, which was coming from the pronounced fusing of silica nanoparticles during the calcined process. Conversely, CRHA-Li4SiO4 achieved porous agglomerates of submicron particles

  19. Capture Their Attention: Capturing Lessons Using Screen Capture Software

    Science.gov (United States)

    Drumheller, Kristina; Lawler, Gregg

    2011-01-01

    When students miss classes for university activities such as athletic and academic events, they inevitably miss important class material. Students can get notes from their peers or visit professors to find out what they missed, but when students miss new and challenging material these steps are sometimes not enough. Screen capture and recording…

  20. Benign versus malignant vertebral compression fractures: distinction with T1-weighted, fast spin-echo T2-weighted, and fat-suppressed gadolinium-enhanced T1-weighted images

    International Nuclear Information System (INIS)

    To differentiate malignant vertebral compression fractures from benign fractures, as seen on spin-echo T1-wieghted, fast spin-echo T2-weighted, and fat-suppressed gadolinium-enhanced T1-weighted MR images. Thirty two benign (18 acute and 14 chronic) and 28 malignant vertebral collapses were studied in 54 patients aged between 15 and 78 (mean, 51) years. Malignant compression fractures involved only metastasis. We obtained sagittal and axial fast spin-echo T2-weighted images, and unenhanced and fat-suppressed gadolinium-enhanced T1-weighted images, and analyzed MR signal intensity, enhancement patterns, and morphologic changes including convex posterior cortex vs retropulsion of a bone fragment, focal vs diffuse paraspinal mass, and epidural mass. All cases of acute benign and malignant compression fractures showed low signal intensity within the vertebral body on T1-weighted images, and substantial contrast enhancement on fat-suppressed gadolinium-enhanced T1-weighted images. Acute benign and malignant compression fractures were distinguished on the basis of three signal intensity characteristics : hypointense band (acute benign cases 77% ; malignant cases 0%), diffuse low signal intensity(17% vs 86%) and involvement of pedicle (0% vs 75%). Fast spin-echo T2-weighted images played little role in distinguishing between the two. Three morphologic changes were suggestive of malignancy : convex posterior cortex (malignant cases 75% ; benign 0%), epidural mass (79% vs 5%), and focal paraspinal mass (57% vs 0%). Retropulsion of a bone fragment (benign cases 63% ; malignant cases 14%) was preferable for benignancy. In addition, thin diffuse paraspinal mass (benign cases 15% ; malignant cases 14%) was seen. The morphologic and signal intensity characteristics seen on T1-weighted images were useful for distinguishing benign and malignant vertebral compression fractures. Fast spin-echo T2-weighted and fat-suppressed gadolinium-enhanced T1-weighted images played little role

  1. Fast weathering of olivine in high-energy shallow seas for cost-effective CO2 capture as a cheap alternative for CCS, and effective mitigation of ocean acidification

    Science.gov (United States)

    De Boer, P. L.; Schuiling, R. D.

    2013-12-01

    Spreading of olivine in high-energy shelf seas can counteract human CO2 emissions and ocean acidification against a price well below that of CCS and other methods. In the reaction: Mg(Fe)2SiO4 (olivine) + 4 H2O --> 2 Mg(Fe)2+ + 4 OH- + H4SiO4 followed by 4 OH- + 4 CO2 --> 4 HCO3-, CO2 is consumed, while Mg2+, Fe2+, H4SiO4 and HCO3- are produced. Contrary to the paradigm that olivine weathering in nature is a slow process, flume experiments mimicking high-energy shallow marine environments show a fast reaction, consuming CO2, and raising the pH at short notice. This must be because under immobile conditions a silica coating develops and retards or stops the reaction. In high-energy shallow marine environments such silica coatings are abraded so that the chemical reaction can continue. When kept in motion also large olivine grains and gravels rubbing and bumping against each other and against other sediment grains weather quickly. The experiments also show that fine micron- to silt-sized olivine particles are produced, and that the chemical reaction is fast. The chemical weathering of 7 km3 olivine would be needed on a yearly basis in order to compensate the human CO2 emissions. This seems very much. It is, however, of the same order of magnitude as the volume of fossil fuels (in oil equivalents ~10 km3) that are burnt annually. Olivine is readily available at the Earth' surface on all continents, and past mining efforts show that such volume of 7 km3 is exceeded by existing mines; e.g. the Bingham Canyon open pit mine in Utah has an excavated volume of 25 km3. Hydrocarbons, on the other hand, are commonly retrieved with great efforts, from great depths, and often at remote locations. The annual spreading of large amounts of olivine (and/or serpentinite) in high-energy shelf seas where coarse sand and gravel can be transported, will counteract human CO2 production by fossil fuel burning and ocean acidification against a price well below that of other methods. For

  2. Microwave-enhanced synthesis of magnetic porous covalent triazine-based framework composites for fast separation of organic dye from aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Wang; Liang Fei; Li Cun [Laboratory of Advanced Porous Materials, School of Chemistry and Chemical Engineering, Anhui University, 3rd Feixi Road, Hefei 230039, Anhui Province (China); Qiu Lingguang, E-mail: lgqiu@ahu.edu.cn [Laboratory of Advanced Porous Materials, School of Chemistry and Chemical Engineering, Anhui University, 3rd Feixi Road, Hefei 230039, Anhui Province (China); Yuan Yupeng; Peng Fumin; Jiang Xia; Xie Anjian; Shen Yuhua [Laboratory of Advanced Porous Materials, School of Chemistry and Chemical Engineering, Anhui University, 3rd Feixi Road, Hefei 230039, Anhui Province (China); Zhu Junfa [National Synchrocyclotron Radiation Laboratory, University of Science and Technology of China, Hefei 230029 (China)

    2011-02-28

    Graphical abstract: - Abstract: A novel type of magnetic porous carbonaceous polymeric material, CTF/Fe{sub 2}O{sub 3} composite (CTF = covalent triazine-based framework), has been synthesized by a facile microwave-enhanced high-temperature ionothermal method. By selecting ZnCl{sub 2} as a reaction medium and the Lewis acid catalyst, and choosing FeCl{sub 3}.6H{sub 2}O as an iron oxide precursor, a series of CTF/Fe{sub 2}O{sub 3} composites with different {gamma}-Fe{sub 2}O{sub 3} contents has been prepared in 60 min. The resulting samples were characterized by the X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), vibration sample magnetometer (VSM), and N{sub 2} sorption-desorption isotherms. The obtained CTF/Fe{sub 2}O{sub 3} composites exhibit high surface areas (930-1149 m{sup 2} g{sup -1}), and their saturation magnetizations at 300 K vary from 1.1 to 5.9 emu g{sup -1}, depending respectively on different Fe{sub 2}O{sub 3} contents (6.43-12.43 wt%) in the CTF/Fe{sub 2}O{sub 3} composites. The CTF/Fe{sub 2}O{sub 3} composites were applied to remove organic dye from aqueous solution by selecting methyl orange as a model molecule, and both high adsorption capacity (291 mg g{sup -1}, corresponding to 0.889 mmol g{sup -1}) and fast adsorption kinetics (k{sub ads} = 4.31 m{sup 2} mg{sup -1} min{sup -1}) were observed.

  3. The Domain II S4-S5 Linker in Nav1.9: A Missense Mutation Enhances Activation, Impairs Fast Inactivation, and Produces Human Painful Neuropathy.

    Science.gov (United States)

    Han, Chongyang; Yang, Yang; de Greef, Bianca T A; Hoeijmakers, Janneke G J; Gerrits, Monique M; Verhamme, Camiel; Qu, Jian; Lauria, Giuseppe; Merkies, Ingemar S J; Faber, Catharina G; Dib-Hajj, Sulayman D; Waxman, Stephen G

    2015-06-01

    Painful small fiber neuropathy is a challenging medical condition with no effective treatment. Non-genetic causes can be identified in one half of the subjects. Gain-of-function variants of sodium channels Nav1.7 and Nav1.8 have recently been associated with painful small fiber neuropathy. More recently, mutations of sodium channel Nav1.9 have been linked to human pain disorders, with two gain-of-function mutations found in patients with painful small fiber neuropathy. Here we report a novel Nav1.9 mutation, a glycine 699 substitution by arginine (G699R) in the domain II S4-S5 linker, identified in a patient with painful small fiber neuropathy. In this study, we assayed the mutant channels by voltage-clamp in superior cervical ganglion neurons, which do not produce endogenous Nav1.8 or Nav1.9 currents, and provide a novel platform where Nav1.9 is expressed at relatively high levels. Voltage-clamp analysis showed that the mutation hyperpolarizes (-10.1 mV) channel activation, depolarizes (+6.3 mV) steady-state fast inactivation, slows deactivation, and enhances ramp responses compared with wild-type Nav1.9 channels. Current-clamp analysis showed that the G699R mutant channels render dorsal root ganglion neurons hyperexcitable, via depolarized resting membrane potential, reduced current threshold and increased evoked firing. These observations show that the domain II S4-S5 linker plays an important role in the gating of Nav1.9 and demonstrates that a mutation in this linker is linked to a common pain disorder. PMID:25791876

  4. Overriding auditory attentional capture.

    Science.gov (United States)

    Dalton, Polly; Lavie, Nilli

    2007-02-01

    Attentional capture by color singletons during shape search can be eliminated when the target is not a feature singleton (Bacon & Egeth, 1994). This suggests that a "singleton detection" search strategy must be adopted for attentional capture to occur. Here we find similar effects on auditory attentional capture. Irrelevant high-intensity singletons interfered with an auditory search task when the target itself was also a feature singleton. However, singleton interference was eliminated when the target was not a singleton (i.e., when nontargets were made heterogeneous, or when more than one target sound was presented). These results suggest that auditory attentional capture depends on the observer's attentional set, as does visual attentional capture. The suggestion that hearing might act as an early warning system that would always be tuned to unexpected unique stimuli must therefore be modified to accommodate these strategy-dependent capture effects. PMID:17557587

  5. Advantages of T2 reversed fast spin-echo image and enhanced three-dimensional surface MR angiography for the diagnosis of cerebral arteriovenous malformations

    International Nuclear Information System (INIS)

    Although the anatomical investigation of cerebral arteriovenous malformation (AVM) with conventional neuro-imagings considerably supports the preoperative evaluation, it is still hard to dissect the detailed anatomical conformations of AVMs such as location of nidus, identification of feeding arteries or draining veins, and the three-dimensional configuration of nidus in sulci or gyri. In this study, we investigated the efficacy of enhanced three-dimensional surface MR angiography (surface MRA) and T2 reversed image (T2R image) in the diagnosis and surgical planning for cerebral AVMs. The diagnostic accuracy was studied in twelve AVMs: four AVMs closed to motor area, one to Broca area, one to Wernicke area, four in temporal lobe, and two in occipital lobe. Images were obtained with a SIGNA HORIZON LX 1.5T VER 8.2. To construct T2R, the brain is scanned by fast SE method with long TR and was displayed with the reversed gray scale, which seemed similar to T1WI. Surface MRA is a fusion image of MRA and surface image in the workstation. The original data was obtained by enhanced 3D-SPGR method. MRA image was reconstructed with MIP method, and surface image was manipulated with a volume rendering method. T2R images demonstrated seven sulcal AVMs, three gyral AVMs, and two sulco-gyral AVMs; five AVMs located on cortex, four extended to subcortex, and three to paraventricular brain. The images clearly showed six AVMs had hypervascular network such as modja-modja vascular formation. Surface MRA represented nidus adjacent to eloquent area. They were present in central sulcus, precentral sulcus, intraparietal sulcus, inferior frontal sulcus, sylvian fissure, superior temporal sulcus, inferior temporal sulcus, superior temporal gyrus, inferior temporal gyrus, medial temporal gyrus, premotor area and superior frontal sulcus, precuneus and parieto-occipital sulcus. It was easy to identify the point of feeding arteries going down into the sulcus and the junction-point of nidus

  6. Advantages of T2 reversed fast spin-echo image and enhanced three-dimensional surface MR angiography for the diagnosis of cerebral arteriovenous malformations

    Energy Technology Data Exchange (ETDEWEB)

    Tanabe, Sumiyoshi; Honmou, Osamu; Minamida, Yoshihiro; Hashi, Kazuo [Sapporo Medical Univ. (Japan). School of Medicine

    2001-09-01

    Although the anatomical investigation of cerebral arteriovenous malformation (AVM) with conventional neuro-imagings considerably supports the preoperative evaluation, it is still hard to dissect the detailed anatomical conformations of AVMs such as location of nidus, identification of feeding arteries or draining veins, and the three-dimensional configuration of nidus in sulci or gyri. In this study, we investigated the efficacy of enhanced three-dimensional surface MR angiography (surface MRA) and T2 reversed image (T2R image) in the diagnosis and surgical planning for cerebral AVMs. The diagnostic accuracy was studied in twelve AVMs: four AVMs closed to motor area, one to Broca area, one to Wernicke area, four in temporal lobe, and two in occipital lobe. Images were obtained with a SIGNA HORIZON LX 1.5T VER 8.2. To construct T2R, the brain is scanned by fast SE method with long TR and was displayed with the reversed gray scale, which seemed similar to T1WI. Surface MRA is a fusion image of MRA and surface image in the workstation. The original data was obtained by enhanced 3D-SPGR method. MRA image was reconstructed with MIP method, and surface image was manipulated with a volume rendering method. T2R images demonstrated seven sulcal AVMs, three gyral AVMs, and two sulco-gyral AVMs; five AVMs located on cortex, four extended to subcortex, and three to paraventricular brain. The images clearly showed six AVMs had hypervascular network such as modja-modja vascular formation. Surface MRA represented nidus adjacent to eloquent area. They were present in central sulcus, precentral sulcus, intraparietal sulcus, inferior frontal sulcus, sylvian fissure, superior temporal sulcus, inferior temporal sulcus, superior temporal gyrus, inferior temporal gyrus, medial temporal gyrus, premotor area and superior frontal sulcus, precuneus and parieto-occipital sulcus. It was easy to identify the point of feeding arteries going down into the sulcus and the junction-point of nidus

  7. SElf-gated Non-Contrast-Enhanced FUnctional Lung imaging (SENCEFUL) using a quasi-random fast low-angle shot (FLASH) sequence and proton MRI.

    Science.gov (United States)

    Fischer, André; Weick, Stefan; Ritter, Christian O; Beer, Meinrad; Wirth, Clemens; Hebestreit, Helge; Jakob, Peter M; Hahn, Dietbert; Bley, Thorsten; Köstler, Herbert

    2014-08-01

    Obtaining functional information on the human lung is of tremendous interest in the characterization of lung defects and pathologies. However, pulmonary ventilation and perfusion maps usually require contrast agents and the application of electrocardiogram (ECG) triggering and breath holds to generate datasets free of motion artifacts. This work demonstrates the possibility of obtaining highly resolved perfusion-weighted and ventilation-weighted images of the human lung using proton MRI and the SElf-gated Non-Contrast-Enhanced FUnctional Lung imaging (SENCEFUL) technique. The SENCEFUL technique utilizes a two-dimensional fast low-angle shot (FLASH) sequence with quasi-random sampling of phase-encoding (PE) steps for data acquisition. After every readout, a short additional acquisition of the non-phase-encoded direct current (DC) signal necessary for self-gating was added. By sorting the quasi-randomly acquired data according to respiratory and cardiac phase derived from the DC signal, datasets of representative respiratory and cardiac cycles could be accurately reconstructed. By application of the Fourier transform along the temporal dimension, functional maps (perfusion and ventilation) were obtained. These maps were compared with dynamic contrast-enhanced (DCE, perfusion) as well as standard Fourier decomposition (FD, ventilation) reference datasets. All datasets were additionally scored by two experienced radiologists to quantify image quality. In addition, one initial patient examination using SENCEFUL was performed. Functional images of healthy volunteers and a patient diagnosed with hypoplasia of the left pulmonary artery and left-sided pulmonary fibrosis were successfully obtained. Perfusion-weighted images corresponded well to DCE-MRI data; ventilation-weighted images offered a significantly better depiction of the lung periphery compared with standard FD. Furthermore, the SENCEFUL technique hints at a potential clinical relevance by successfully detecting

  8. Neutron Capture Nucleosynthesis

    OpenAIRE

    Kiss, Miklos

    2016-01-01

    Heavy elements (beyond iron) are formed in neutron capture nucleosynthesis processes. We have proposed a simple unified model to investigate the neutron capture nucleosynthesis in arbitrary neutron density environment. We have also investigated what neutron density is required to reproduce the measured abundance of nuclei assuming equilibrium processes. We found both of these that the medium neutron density has a particularly important role at neutron capture nucleosynthesis. About these resu...

  9. Overriding auditory attentional capture

    OpenAIRE

    Dalton, Polly; Lavie, Nilli

    2007-01-01

    Attentional capture by color singletons during shape search can be eliminated when the target is not a feature singleton (Bacon & Egeth, 1994). This suggests that a "singleton detection" search strategy must be adopted for attentional capture to occur. Here we find similar effects on auditory attentional capture. Irrelevant high-intensity singletons interfered with an auditory search task when the target itself was also a feature singleton. However, singleton interference was eliminated when ...

  10. Neutron Capture Nucleosynthesis

    CERN Document Server

    Kiss, Miklos

    2016-01-01

    Heavy elements (beyond iron) are formed in neutron capture nucleosynthesis processes. We have proposed a simple unified model to investigate the neutron capture nucleosynthesis in arbitrary neutron density environment. We have also investigated what neutron density is required to reproduce the measured abundance of nuclei assuming equilibrium processes. We found both of these that the medium neutron density has a particularly important role at neutron capture nucleosynthesis. About these results most of the nuclei can formed at medium neutron capture density environment e.g. in some kind of AGB stars. Besides these observations our model is capable to use educational purpose.

  11. Encapsulated liquid sorbents for carbon dioxide capture

    Science.gov (United States)

    Vericella, John J.; Baker, Sarah E.; Stolaroff, Joshuah K.; Duoss, Eric B.; Hardin, James O.; Lewicki, James; Glogowski, Elizabeth; Floyd, William C.; Valdez, Carlos A.; Smith, William L.; Satcher, Joe H.; Bourcier, William L.; Spadaccini, Christopher M.; Lewis, Jennifer A.; Aines, Roger D.

    2015-02-01

    Drawbacks of current carbon dioxide capture methods include corrosivity, evaporative losses and fouling. Separating the capture solvent from infrastructure and effluent gases via microencapsulation provides possible solutions to these issues. Here we report carbon capture materials that may enable low-cost and energy-efficient capture of carbon dioxide from flue gas. Polymer microcapsules composed of liquid carbonate cores and highly permeable silicone shells are produced by microfluidic assembly. This motif couples the capacity and selectivity of liquid sorbents with high surface area to facilitate rapid and controlled carbon dioxide uptake and release over repeated cycles. While mass transport across the capsule shell is slightly lower relative to neat liquid sorbents, the surface area enhancement gained via encapsulation provides an order-of-magnitude increase in carbon dioxide absorption rates for a given sorbent mass. The microcapsules are stable under typical industrial operating conditions and may be used in supported packing and fluidized beds for large-scale carbon capture.

  12. Carbon Capture and Storage

    NARCIS (Netherlands)

    Benson, S.M.; Bennaceur, K.; Cook, P.; Davison, J.; Coninck, H. de; Farhat, K.; Ramirez, C.A.; Simbeck, D.; Surles, T.; Verma, P.; Wright, I.

    2012-01-01

    Emissions of carbon dioxide, the most important long-lived anthropogenic greenhouse gas, can be reduced by Carbon Capture and Storage (CCS). CCS involves the integration of four elements: CO 2 capture, compression of the CO2 from a gas to a liquid or a denser gas, transportation of pressurized CO 2

  13. CAPTURED India Country Evaluation

    NARCIS (Netherlands)

    O'Donoghue, R.; Brouwers, J.H.A.M.

    2012-01-01

    This report provides the findings of the India Country Evaluation and is produced as part of the overall CAPTURED End Evaluation. After five years of support by the CAPTURED project the End Evaluation has assessed that results are commendable. I-AIM was able to design an approach in which health fol

  14. Direct thermal neutron capture

    International Nuclear Information System (INIS)

    We discuss the direct-capture theory pertaining to primary electric dipole (E1) transitions following slow-neutron capture. For light nuclides that we have studied (including 9Be, 12C, 13C, 24Mg, 25Mg, 26Mg, 32S, 33S, 34S, 40Ca, and 44Ca), estimates of direct-capture cross sections using optical-model potentials with physically realistic parameters, are in reasonable agreement with the data. Minor disagreements that exist are consistent with extrapolations to light nuclides of generally accepted formulations of compound-nucleus capture. We also discuss the channel-capture approximation which is, in general, a good representation of these cross sections in heavier nuclei particularly if the scattering lengths are not different from the corresponding potential radii. We also draw attention to cases where the use of this formula leads to inaccurate predictions. 9 refs., 1 fig., 2 tab

  15. Muon capture in hydrogen

    International Nuclear Information System (INIS)

    In this lecture I will mainly speak about the recent results obtained by the Saclay-CERN-Bologna (SCB) collaboration on the muon capture rate at rest in liquid hydrogen.In the first talk I shall first briefly remind the theoretical description of the capture process, then describe the experimental difficulties and procedures and finally present the results obtained. In the second talk I shall compare them to other capture experiments on the proton and present the informations that are provided by muon capture in hydrogen, especially for the PCAC hypothesis, the second class currents and the μ-e universality. Finally I shall present the possible muon capture experiments on the proton that could still be undertaken in order to improve our present knowledge of the subject

  16. Nickel Nanoparticles for Enhancing Carbon Capture

    OpenAIRE

    Gaurav Ashok Bhaduri; Mohammed A. H. Alamiry; Lidija Šiller

    2015-01-01

    Hydration reaction of CO2 is one of the rate limiting steps for CO2 absorption (in aqueous solutions) and aqueous CO2 mineralization. The catalytic activity of nickel nanoparticles (NiNPs) for CO2 hydration is studied at different temperatures, pH, and low CO2 partial pressures to mimic the true flue gas conditions. Results show that NiNPs can work as active catalyst for hydration of CO2 in applications such as CO2 separation and CO2 mineralization. The NiNPs display optimum activity within 2...

  17. Workshop on neutron capture therapy

    Energy Technology Data Exchange (ETDEWEB)

    Fairchild, R.G.; Bond, V.P. (eds.)

    1986-01-01

    Potentially optimal conditions for Neutron Capture Therapy (NCT) may soon be in hand due to the anticipated development of band-pass filtered beams relatively free of fast neutron contaminations, and of broadly applicable biomolecules for boron transport such as porphyrins and monoclonal antibodies. Consequently, a number of groups in the US are now devoting their efforts to exploring NCT for clinical application. The purpose of this Workshop was to bring these groups together to exchange views on significant problems of mutual interest, and to assure a unified and effective approach to the solutions. Several areas of preclinical investigation were deemed to be necessary before it would be possible to initiate clinical studies. As neither the monomer nor the dimer of sulfhydryl boron hydride is unequivocally preferable at this time, studies on both compounds should be continued until one is proven superior.

  18. Workshop on neutron capture therapy

    International Nuclear Information System (INIS)

    Potentially optimal conditions for Neutron Capture Therapy (NCT) may soon be in hand due to the anticipated development of band-pass filtered beams relatively free of fast neutron contaminations, and of broadly applicable biomolecules for boron transport such as porphyrins and monoclonal antibodies. Consequently, a number of groups in the US are now devoting their efforts to exploring NCT for clinical application. The purpose of this Workshop was to bring these groups together to exchange views on significant problems of mutual interest, and to assure a unified and effective approach to the solutions. Several areas of preclinical investigation were deemed to be necessary before it would be possible to initiate clinical studies. As neither the monomer nor the dimer of sulfhydryl boron hydride is unequivocally preferable at this time, studies on both compounds should be continued until one is proven superior

  19. Environment assisted electron capture

    International Nuclear Information System (INIS)

    Electrons scattering off isolated atoms or positive atomic ions may be captured in the non-resonant photorecombination or resonant dielectronic recombination processes with the excess energy carried off by a photon. We demonstrate that in a medium a new interatomic process becomes important, where in the electron capture by an atom or atomic ion the energy is transferred to a neigbouring species ionising it. We discuss different manifestations of this interatomic Coulombic electron capture and estimate its efficiency for a number of realistic systems.

  20. Pulse shape discrimination between (fast or thermal) neutrons and gamma rays with plastic scintillators: State of the art

    Energy Technology Data Exchange (ETDEWEB)

    Bertrand, Guillaume H.V. [CEA, LIST, Laboratoire Capteurs & Architectures Électroniques, CEA Saclay, F-91191 Gif-sur-Yvette cedex (France); Hamel, Matthieu, E-mail: matthieu.hamel@cea.fr [CEA, LIST, Laboratoire Capteurs & Architectures Électroniques, CEA Saclay, F-91191 Gif-sur-Yvette cedex (France); Normand, Stéphane [CEA, DAM, Le Ponant, 25 rue Leblanc, F-75015 Paris (France); Sguerra, Fabien [CEA, LIST, Laboratoire Capteurs & Architectures Électroniques, CEA Saclay, F-91191 Gif-sur-Yvette cedex (France)

    2015-03-11

    We would like to present here with the eyes of the chemist the most recent developments of plastic scintillators (PS) for neutron detection. This review covers the period from 2000 to August 2014, and is fragmented in two main chapters. The first chapter deals with the chemical modifications for thermal neutron capture, whereas the second chapter presents the various strategies used to enhance the response to fast neutrons via pulse shape discrimination. For each chapter the theory is also explained.

  1. Pulse shape discrimination between (fast or thermal) neutrons and gamma rays with plastic scintillators: State of the art

    International Nuclear Information System (INIS)

    We would like to present here with the eyes of the chemist the most recent developments of plastic scintillators (PS) for neutron detection. This review covers the period from 2000 to August 2014, and is fragmented in two main chapters. The first chapter deals with the chemical modifications for thermal neutron capture, whereas the second chapter presents the various strategies used to enhance the response to fast neutrons via pulse shape discrimination. For each chapter the theory is also explained

  2. Neutrinoless double electron capture

    CERN Document Server

    Kotila, J; Iachello, F

    2015-01-01

    Direct determination of the neutrino mass is at the present time one of the most important aims of experimental and theoretical research in nuclear and particle physics. A possible way of detection is through neutrinoless double electron capture, $0\

  3. Activists versus Captured Regulators

    OpenAIRE

    Daubanes, Julien; Rochet, Jean-Charles

    2013-01-01

    We analyze the consequences of activism in a regulated industry where the regulator has been captured by the industry. Unlike ordinary economic agents, activists are insensitive to monetary incentives. Moreover, they are less well informed than regulators and their actions generate dead-weight costs. Yet we find that activism may increase social welfare because it disciplines captured regulators and reduces the social cost of imperfect regulatory systems.

  4. Muon capture by tritium

    International Nuclear Information System (INIS)

    The muon capture rate is computed with realistic wave function for the initial tritium nuclei (Faddeev equations on configuration space with realistic potentials), and plane wave approximation for the final three neutrons, with the effective Hamiltonian of Fujii and Primakoff for muon capture and via a non energy weighted sum rule. Such a forbidden transition is hoped to be a probe for exchange current contributions

  5. Fast 3D coronary artery contrast-enhanced magnetic resonance angiography with magnetization transfer contrast, fat suppression and parallel imaging as applied on an anthropomorphic moving heart phantom

    NARCIS (Netherlands)

    Irwan, Roy; Russel, Inis K.; Sijens, Paul E.

    2006-01-01

    A magnetic resonance sequence for high-resolution imaging of coronary arteries in a very short acquisition time is presented. The technique is based on fast low-angle shot and uses fat saturation and magnetization transfer contrast Prepulses to improve image contrast. GeneRalized Autocalibrating Par

  6. Muon capture at PSI

    CERN Document Server

    Winter, Peter

    2010-01-01

    Measuring the rate of muon capture in hydrogen provides one of the most direct ways to study the axial current of the nucleon. The MuCap experiment uses a negative muon beam stopped in a time projection chamber operated with ultra-pure hydrogen gas. Surrounded by a decay electron detector, the lifetime of muons in hydrogen can be measured to determine the singlet capture rate Lambda_s to a final precision of 1%. The capture rate determines the nucleon's pseudoscalar form factor g_p. A first result, g_p = 7.3 +- 1.1, has been published and the final analysis of the full statistics will reduce the error by a factor of up to 3. Muon capture on the deuteron probes the weak axial current in the two-nucleon system. Within the framework of effective field theories the calculation of such two-nucleon processes involving the axial current requires the knowledge of one additional low energy constant which can be extracted from the doublet capture rate Lambda_d. The same constant then allows to model-independently calcu...

  7. Muon Capture in Deuterium

    CERN Document Server

    Ricci, P; Mosconi, B; Smejkal, J

    2009-01-01

    Model dependence of the capture rates of the negative muon capture in deuterium is studied starting from potential models and the weak two-body meson exchange currents constructed in the tree approximation and also from an effective field theory. The tree one-boson exchange currents are derived from the hard pion chiral Lagrangians of the $N \\Delta \\pi \\rho \\omega a_1$ system. If constructed in conjunction with the one-boson exchange potentials, the capture rates can be calculated consistently. On the other hand, the effective field theory currents, constructed within the heavy baryon chiral perturbation theory, contain a low energy constant $\\hat d ^R$ that cannot be extracted from data at the one-particle level nor determined from the first principles. Comparative analysis of the results for the doublet transition rate allows us to extract the constant $\\hat d ^R$.

  8. US Spacesuit Knowledge Capture

    Science.gov (United States)

    Chullen, Cinda; Thomas, Ken; McMann, Joe; Dolan, Kristi; Bitterly, Rose; Lewis, Cathleen

    2011-01-01

    The ability to learn from both the mistakes and successes of the past is vital to assuring success in the future. Due to the close physical interaction between spacesuit systems and human beings as users, spacesuit technology and usage lends itself rather uniquely to the benefits realized from the skillful organization of historical information; its dissemination; the collection and identification of artifacts; and the education of those in the field. The National Aeronautics and Space Administration (NASA), other organizations and individuals have been performing United States (U.S.) Spacesuit Knowledge Capture since the beginning of space exploration. Avenues used to capture the knowledge have included publication of reports; conference presentations; specialized seminars; and classes usually given by veterans in the field. More recently the effort has been more concentrated and formalized whereby a new avenue of spacesuit knowledge capture has been added to the archives in which videotaping occurs engaging both current and retired specialists in the field presenting technical scope specifically for education and preservation of knowledge. With video archiving, all these avenues of learning can now be brought to life with the real experts presenting their wealth of knowledge on screen for future learners to enjoy. Scope and topics of U.S. spacesuit knowledge capture have included lessons learned in spacesuit technology, experience from the Gemini, Apollo, Skylab and Shuttle programs, hardware certification, design, development and other program components, spacesuit evolution and experience, failure analysis and resolution, and aspects of program management. Concurrently, U.S. spacesuit knowledge capture activities have progressed to a level where NASA, the National Air and Space Museum (NASM), Hamilton Sundstrand (HS) and the spacesuit community are now working together to provide a comprehensive closed-looped spacesuit knowledge capture system which includes

  9. Development of solid adsorbent materials for CO₂capture

    OpenAIRE

    Ogbuka, Chidi Premie

    2013-01-01

    The application of solid adsorbents for gas separation in pre-combustion carbon capture from gasification processes has gained attention in recent times. This is due to the potential of the technology to reduce the overall energy penalty associated with the capture process. However, this requires the development of solid adsorbent materials with large selectivity, large adsorption capacity, fast adsorption kinetics for CO2 coupled with good mechanical strength and thermal stability. In this ...

  10. Application note : using open source schematic capture tools with Xyce.

    Energy Technology Data Exchange (ETDEWEB)

    Russo, Thomas V.

    2013-08-01

    The development of the XyceTM Parallel Electronic Simulator has focused entirely on the creation of a fast, scalable simulation tool, and has not included any schematic capture or data visualization tools. This application note will describe how to use the open source schematic capture tool gschem and its associated netlist creation tool gnetlist to create basic circuit designs for Xyce, and how to access advanced features of Xyce that are not directly supported by either gschem or gnetlist.

  11. Localized fast neutron flux enhancement for damage experiments in a research reactor; Accroissement local du flux rapide pour des experiences de dommages dans un reacteur de recherche

    Energy Technology Data Exchange (ETDEWEB)

    Malouch, F

    2003-06-01

    In irradiation experiments on materials in the core of the Osiris reactor (CEA-Saclay) we seek to increase damage in irradiated samples and to reduce the duration of their stay in the core. Damage is essentially caused by fast neutrons (E {>=} 1 MeV); we have therefore pursued the possibility of a localized increase of their level in an irradiation experiment by using a flux converter device made up of fissile material arranged according to a suitable geometry that allows the converter to receive experiments. We have studied several parameters that are influential in the increase of fast neutron flux within the converter. We have also considered the problem of the converter's cooling in the core and its effect on the operation of the reactor. We have carried out a specific neutron calculation scheme based on the modular 2D-transport code APOLLO2 using a two-level transport method. Experimental validation of the flux calculation scheme was carried out in the ISIS reactor, the mock-up of OSIRIS, by optimizing the loading of fuel elements in the core. The experimental results show that the neutron calculation scheme computes the fluxes in close agreement with the measurements especially the fast flux. This study allows us to master the essential physical parameters needed for the design of a flux converter in an MTR reactor. (author)

  12. Exploiting the Capture Effect to Improve WLAN Throughput

    OpenAIRE

    Patras, Paul; Qi, Hanghang; Malone, David

    2012-01-01

    In practical WLAN deployments, the capture effect has been shown to enhance the performance of stations residing close to the AP, while putting at disadvantage the distant nodes. In this paper, we introduce an analytical model to characterise the performance of 802.11 devices with heterogeneous capture probabilities and different network loads, and explore the interaction between the MAC operation and PHY capture. Unlike previous studies, we reveal that the throughput of ...

  13. Algal Energy Conversion and Capture

    Science.gov (United States)

    Hazendonk, P.

    2015-12-01

    We address the potential for energy conversions and capture for: energy generation; reduction in energy use; reduction in greenhouse gas emissions; remediation of water and air pollution; protection and enhancement of soil fertility. These processes have the potential to sequester carbon at scales that may have global impact. Energy conversion and capture strategies evaluate energy use and production from agriculture, urban areas and industries, and apply existing and emerging technologies to reduce and recapture energy embedded in waste products. The basis of biocrude production from Micro-algal feedstocks: 1) The nutrients from the liquid fraction of waste streams are concentrated and fed into photo bioreactors (essentially large vessels in which microalgae are grown) along with CO2 from flue gasses from down stream processes. 2) The algae are processed to remove high value products such as proteins and beta-carotenes. The advantage of algae feedstocks is the high biomass productivity is 30-50 times that of land based crops and the remaining biomass contains minimal components that are difficult to convert to biocrude. 3) The remaining biomass undergoes hydrothermal liquefaction to produces biocrude and biochar. The flue gasses of this process can be used to produce electricity (fuel cell) and subsequently fed back into the photobioreactor. The thermal energy required for this process is small, hence readily obtained from solar-thermal sources, and furthermore no drying or preprocessing is required keeping the energy overhead extremely small. 4) The biocrude can be upgraded and refined as conventional crude oil, creating a range of liquid fuels. In principle this process can be applied on the farm scale to the municipal scale. Overall, our primary food production is too dependent on fossil fuels. Energy conversion and capture can make food production sustainable.

  14. CAPTURED End Evaluation Synthesis Report

    NARCIS (Netherlands)

    Brouwers, J.H.A.M.

    2012-01-01

    This report provides the findings of the Synthesis Study of the CAPTURED Evaluation and is produced as part of the overall CAPTURED End Evaluation. After five years of support by the CAPTURED project the three CAPTURED partners have achieved commendable results. Ten lessons learned are formulated th

  15. Theory of electron capture

    International Nuclear Information System (INIS)

    The historical development of a theoretical model for the electron-capture detector, sometimes called the 'classical' model, is presented and the model as it stands today is described. This is followed by a comparison of the model with experimental data obtained with other techniques since the early development of the theory and finally a section on correlations and predictions is presented. (Auth.)

  16. Interfacial effects in fast reactors

    International Nuclear Information System (INIS)

    The problem of increased resonance capture rates near zone interfaces in fast reactor media has been examined both theoretically and experimentally. An interface traversing assembly was designed, constructed and employed to measure U-238 capture rates near th blanket--reflector interface in the MIT Blanket Test Facility. Prior MIT experiments on a thorium--uranium interface in a blanket assembly were also reanalyzed. Extremely localized fertile capture rate increases of on the order of 50% were measured immediately at the interfaces relative to extrapolation of asymptotic interior traverses, and relative to state-of-the-art (LIB-IV, SPHINX, ANISN/2DB) calculations which employ infinite-medium self-shielding throughout a given zone. A method was developed to compute a spatially varying background scattering cross section per absorber nucleus which takes into account both homogeneous and heterogeneous effects on the interface flux transient

  17. Students Approach to Learning and Their Use of Lecture Capture

    Science.gov (United States)

    Vajoczki, Susan; Watt, Susan; Marquis, Nick; Liao, Rose; Vine, Michelle

    2011-01-01

    This study examined lecture capture as a way of enhancing university education, and explored how students with different learning approaches used lecture capturing (i.e., podcasts and vodcasts). Results indicate that both deep and surface learners report increased course satisfaction and better retention of knowledge in courses with traditional…

  18. Enhanced production possibility of the therapeutic radionuclides 64Cu, 67Cu and 89Sr via (n,p) reactions induced by fast spectral neutrons

    OpenAIRE

    Spahn, I.; Coenen, H. H.; Qaim, S. M.

    2004-01-01

    Spectrum averaged cross sections for the Zn-64(n, p)Cu-64, Zn-67(n, p)Cu-67 and Y-89(n, p)Sr-89 reactions were measured using a 14 MeV d(Be) neutron source. In each case a clean radiochemical separation was performed and the radioactivity of the product was determined via high-resolution gamma-ray spectrometry or anticoincidence beta(-) counting. The cross sections are three to five times higher than with a fission neutron spectrum. It is postulated that at an intense fast spectral neutron so...

  19. Low circulating levels of IGF-1 in healthy adults are associated with reduced β-cell function, increased intramyocellular lipid, and enhanced fat utilization during fasting

    DEFF Research Database (Denmark)

    Thankamony, Ajay; Capalbo, Donatella; Marcovecchio, M Loredana;

    2014-01-01

    free fatty acids (P = .028) and β-hydroxybutyrate (P = .014), increased accumulation of IMCLs in tibialis anterior muscle (P = .008), and a tendency for elevated fat oxidation rates (P = .058); however, glycerol Ra values were similar. Gene expression of the fatty acid metabolism pathway (P = .0014......) was upregulated, whereas the GLUT1 gene was downregulated (P = .005) in the skeletal muscle in low-IGF subjects. CONCLUSIONS: These data suggest that serum IGF-1 levels could be an important marker of β-cell function and glucose as well as lipid metabolic responses during fasting....

  20. Note: Light output enhanced fast response and low afterglow 6Li glass scintillator as potential down-scattered neutron diagnostics for inertial confinement fusion

    International Nuclear Information System (INIS)

    The characteristics of an APLF80+3Ce scintillator are presented. Its sufficiently fast decay profile, low afterglow, and an improved light output compared to the recently developed APLF80+3Pr, were experimentally demonstrated. This scintillator material holds promise for applications in neutron imaging diagnostics at the energy regions of 0.27 MeV of DD fusion down-scattered neutron peak at the world's largest inertial confinement fusion facilities such as the National Ignition Facility and the Laser Megajoule.

  1. Capturing and storing CO2

    International Nuclear Information System (INIS)

    A promising way to combat global warming is to capture CO2 produced by industry and bury it in deep geologic formations. The processes are technically complex and still expensive. Before it can be captured, CO2 must be separated from other components produced by industrial processes that burn oil, gas, coal or biomass, such as nitrogen and sulfur. The CO2 is then piped down vertically from the storage facility and injected at depths of at least 800 meters. There, it reaches a 'supercritical' state in which it becomes denser and less voluminous. Three types of underground reservoirs have been tested so far: 1 - Deep onshore or offshore saline aquifers: These brackish water-bearing layers constitute the biggest reservoir, with 10,000 billion metric tons of storage capacity. They are also the most evenly distributed geographically, making it easier to find one near the source of emission. 2 - Depleted oil and gas reservoirs: injecting pressurized CO2 helps to dissolve remaining oil and reduce its viscosity. This facilitates the enhanced recovery of oil or gas from nearly depleted reservoirs, adding a potential economic advantage to the operation. The disadvantage of these reservoirs is their distance from CO2-emitting industrial sites. 3 - Unexploited coal seams: the CO2 replaces the methane that is naturally present in the coal bed. The methane can be extracted and marketed by gas companies. There are two additional solutions. The first involves storing the CO2 in carbon 'lakes' in the ocean at a minimum depth of 1,500 meters, but this has been rejected due to concerns about the impacts on the marine ecosystem and how long the CO2 would be contained. The second solution, carbon sequestration by mineral carbonation, is of more interest. Here, CO2 reacts with naturally occurring subsurface calcium and magnesium to become a carbonated rock similar to limestone, which is insoluble and therefore perfectly stable over the long term. The entire CO2 capture, compression

  2. Demonstration of control rod holding stability of the self actuated shutdown system in Joyo for enhancement of fast reactor inherent safety

    International Nuclear Information System (INIS)

    Self actuated shutdown system (SASS) with a Curie point electromagnet (CPEM) has been developed for use in a large-scale liquid metal cooled fast breeder reactor (LMFBR) in order to establish the passive shutdown capability against anticipated transient without scram (ATWS) events. The basic characteristics of SASS have already been investigated by various out-of-pile tests for material elements. As the final stage of the development, the stability of SASS needs to be confirmed under the actual reactor-operational environment with high temperature, high neutron flux, and flowing sodium to ensure the high plant availability factor. For this purpose, the demonstration test of holding stability using the reduced-scale experimental equipment of SASS was conducted in the 1st and 2nd operational cycles of the experimental fast reactor Joyo MK-III. The rod-holding stability and the rod-recovering functions of the driving system to re-connect and pull out the separated control rod were fully confirmed. The results also indicate there is no essential problem for the practical use of SASS about its operational trouble involving the unexpected drop during reactor operation. (author)

  3. Gadolinium neutron capture therapy

    International Nuclear Information System (INIS)

    Gadolinium neutron capture therapy makes use of photons and electrons produced by nuclear reactions between gadolinium and lower-energy neutrons which occur within the tumor. The results of our studies have shown that its radiation effect is mostly of low LET and that the electrons are the significant component in the over-all dose. The dose from gadolinium neutron capture reactions does not seem to increase in proportion to the gadolinium concentration, and the Gd-157 concentration of about 100 μg/ml appears most optimal for therapy. Close contact between gadolinium and the cell is not necessarily required for cell inactivation, however, the effect of electrons released from intracellular gadolinium may be significant. Experimental studies on tumor-bearing mice and rabbits have shown that this is a very promising modality though further improvements in gadolinium delivery to tumors are needed. (author)

  4. Supernova electron capture rates

    CERN Document Server

    Martínez-Pinedo, G

    1999-01-01

    We have calculated the Gamow-Teller strength distributions for the ground states and low lying states of several nuclei that play an important role in the precollapse evolution of supernova. The calculations reproduce the experimental GT distributions nicely. The GT distribution are used to calculate electron capture rates for typical presupernova conditions. The computed rates are noticeably smaller than the presently adopted rates. The possible implications for the supernova evolution are discussed.

  5. Inland capture fisheries

    OpenAIRE

    Welcomme, Robin L.; Cowx, Ian G.; Coates, David; Béné, Christophe; Funge-Smith, Simon; Halls, Ashley; Lorenzen, Kai

    2010-01-01

    The reported annual yield from inland capture fisheries in 2008 was over 10 million tonnes, although real catches are probably considerably higher than this. Inland fisheries are extremely complex, and in many cases poorly understood. The numerous water bodies and small rivers are inhabited by a wide range of species and several types of fisher community with diversified livelihood strategies for whom inland fisheries are extremely important. Many drivers affect the fisheries, including inter...

  6. Laser capture microscopy

    OpenAIRE

    Curran, S.; McKay, J A; McLeod, H L; Murray, G I

    2000-01-01

    Human tissues are composed of complex admixtures of different cell types and their biologically meaningful analysis necessitates the procurement of pure samples of the cells of interest. Many approaches have been used in attempts to overcome this difficulty, including a variety of microdissection methods. This review concerns a recent advance in microdissection techniques, namely laser capture microdissection (LCM). The principle underlying this technique is outlined, and practical issues per...

  7. Quantifying protein diffusion and capture on filaments

    CERN Document Server

    Reithmann, Emanuel; Frey, Erwin

    2015-01-01

    The functional relevance of regulating proteins is often limited to specific binding sites such as the ends of microtubules or actin-filaments. A localization of proteins on these functional sites is of great importance. We present a quantitative theory for a diffusion and capture process, where proteins diffuse on a filament and stop diffusing when reaching the filament's end. It is found that end-association after one-dimensional diffusion is the main source for tip-localization of such proteins. As a consequence, diffusion and capture is highly efficient in enhancing the reaction velocity of enzymatic reactions, where proteins and filament ends are to each other as enzyme and substrate. We show that the reaction velocity can effectively be described within a Michaelis-Menten framework. Together one-dimensional diffusion and capture beats the (three-dimensional) Smoluchowski diffusion limit for the rate of protein association to filament ends.

  8. MRI evaluation of myometrial invasion by endometrial carcinoma. Comparison between fast-spin-echo T2W and coronal FMPSPGR Gadolinium-Dota-Enhanced Sequences

    International Nuclear Information System (INIS)

    Purpose. The depth of myometrial invasion by endometrial carcinoma strongly affects the incidence of metastasis to regional nodes and influences the surgical strategies. The aim of this paper is to compare the results of FSE T2-w and Gadolinium-enhanced FMPSGR MR sequences in assessing the depth of myometrial invasion by endometrial cancer. Materials and methods. Forty-five women with histopathologically-proven endometrial carcinoma underwent preoperative MRI. Axial SE TI w, axial, sagittal and para-coronal FSE T2w and para-coronal Gadolinium enhanced FMPSGR sequences were performed using a high field strength magnet (1.5T). Within one month of MR all patients underwent hysterectomy, and anatomical evaluation of the surgical specimen was done sectioning the uterus along the short axis. Based upon the results of the histological evaluation the results of the FSE T2w and Gadolinium-enhanced sequences were compared and the statistical difference between the results obtained was statistically evaluated. Results. The histological evaluation showed intra mucosal neoplasm in 11 patients, myometrial infiltration less than 50% in 31 patients, myometrial infiltration more than 50% in 12 patients and transmural cancer 1 patient. Statistical evaluation showed that the FSE T2w sequence had a global sensitivity and specificity of 80.6% and 87.6%, respectively, with a mean Negative Predictive Value of 92.6% and a mean Positive Predictive Value of 86%. Gadolinium-enhanced FMPSPGR sequence had a global sensitivity and specificity of 90.6% and 93.3%, respectively, with a mean Negative Predictive Value of 96,3% and a mean Positive Predictive Value of 88%. The staging accuracy (χ2 test) on FMPSPGR images (95%) was higher than that on FSE T2w images (78%). Conclusions. In our experience Gadolinium-enhanced dynamic sequences increase the accuracy of MR imaging in diagnosing the depth of myometrial invasion. In particular they improve the visualisation of the inner myometrium, the so

  9. Fast, multi-wavelength, efficiency-enhanced pixelated devices based on InGaAs/InAlAs quantum-well

    International Nuclear Information System (INIS)

    Several applications utilizing either synchrotron or conventional light sources require fast and efficient pixelated detectors. In order to cover a wide range of experiments, this work investigates the possibility to use InGaAs/InAlAs quantum well devices as photon detectors for a broad range of energies. Owing to their direct, low-energy band gap and high electron mobility, such devices may be used also at room temperature as multi-wavelength sensors from visible light to hard X-rays. Furthermore, internal charge-amplification mechanism can be applied for very low signal levels, while the high carrier mobility allows the design of very fast photon detectors with sub-nanosecond response times.Samples were grown by solid source molecular beam epitaxy on GaAs substrates. Metamorphic In0.75Ga0.25As/ In0.75Al0.25As heterostructures were obtained by relaxing the strain due to the lattice mismatch in the substrate by means of a composition-graded buffer layer. A two-dimensional electron gas forming in an In0.75Ga0.25As quantum well is sandwiched between In0.75Al0.25As barriers and is modulation-doped by a Si δ on its top. The samples have been pixelated by using standard photolithographic techniques. In order to fit commercially available readout chips, a pixelated sensor with pixel size of 172 × 172 μ m2 is currently under development. A small-scale version of the pixelated quantum well sensor has been preliminary tested with 100-fs-wide laser pulses and X-ray synchrotron radiation. The reported results indicate that these sensors respond with 100-ps rise-times to ultra-fast laser pulses. Synchrotron X-ray tests show how these devices exhibit high charge collection efficiencies, which can be imputed to the charge-multiplication effect of the 2D electron gas inside the well

  10. Selective particle capture by asynchronously beating cilia

    Science.gov (United States)

    Ding, Yang; Kanso, Eva

    2015-12-01

    Selective particle filtration is fundamental in many engineering and biological systems. For example, many aquatic microorganisms use filter feeding to capture food particles from the surrounding fluid, using motile cilia. One of the capture strategies is to use the same cilia to generate feeding currents and to intercept particles when the particles are on the downstream side of the cilia. Here, we develop a 3D computational model of ciliary bands interacting with flow suspended particles and calculate particle trajectories for a range of particle sizes. Consistent with experimental observations, we find optimal particle sizes that maximize capture rate. The optimal size depends nonlinearly on cilia spacing and cilia coordination, synchronous vs. asynchronous. These parameters affect the cilia-generated flow field, which in turn affects particle trajectories. The low capture rate of smaller particles is due to the particles' inability to cross the flow streamlines of neighboring cilia. Meanwhile, large particles have difficulty entering the sub-ciliary region once advected downstream, also resulting in low capture rates. The optimal range of particle sizes is enhanced when cilia beat asynchronously. These findings have potentially important implications on the design and use of biomimetic cilia in processes such as particle sorting in microfluidic devices.

  11. Lunar Sulfur Capture System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Sulfur Capture System (LSCS) is an innovative method to capture greater than 90 percent of sulfur gases evolved during thermal treatment of lunar soils....

  12. The CO2 capture and sequestration plan

    International Nuclear Information System (INIS)

    The CO2 capture and sequestration plan is officially one of the most relevant solution in the world control against the greenhouse gas releases. In spite of the multiplication of the pilot plans, this technology delays however to run up. At the moment, it is always the petroleum and natural gas industries, with the enhanced oil recovery process, which highlight this technology. But, without a modification of the support mechanisms, the chances of succeed of the sector could be compromised. (O.M.)

  13. Suspended particle capture by synthetic vegetation in a laboratory flume

    Science.gov (United States)

    Fauria, Kristen E.; Kerwin, Rachel E.; Nover, Daniel; Schladow, S. Geoffrey

    2015-11-01

    Vegetated floodplains and wetlands trap particles, a process that is important for water quality and wetland function and morphology. The rates of particle removal by vegetation remain poorly characterized, especially for small particles and vegetation coated with biofilm. In this study, we measured capture rates of road dust by arrays of grass-like synthetic vegetation in a laboratory flume. We performed 40 experiments in which stem density, flow velocity, the presence of biofilm, and initial particle concentration varied, and used an in situ particle size analyzer to measure the concentration of a continuous particle size distribution (1.25-250 µm diameter). We fit first-order decay models to the particle concentration measurements to determine particle capture rates and found that capture rates increased with particle size, stem density, and the presence of biofilm. Capture rates decreased with increasing flow velocity, which suggests that fast flows may resuspend particles from stems. We also calculated percent particle capture efficiencies and fit a new empirical model for capture efficiency to our results. We found that particle capture efficiency was highest for low stem density treatments and propose that stem density affects capture by altering turbulent kinetic energy.

  14. Gadolinium as a Neutron Capture Therapy Agent

    Science.gov (United States)

    Shih, Jing-Luen Allen

    The clinical results of treating brain tumors with boron neutron capture therapy are very encouraging and researchers around the world are once again making efforts to develop this therapeutic modality. Boron-10 is the agent receiving the most attention for neutron capture therapy but ^{157}Gd is a nuclide that also holds interesting properties of being a neutron capture therapy agent. The objective of this study is to evaluate ^{157}Gd as a neutron capture therapy agent. In this study it is determined that tumor concentrations of about 300 mug ^{157}Gd/g tumor can be achieved in brain tumors with some FDA approved MRI contrast agents such as Gd-DTPA and Gd-DOTA, and up to 628 mug ^{157 }Gd/g tumor can be established in bone tumors with Gd-EDTMP. Monte Carlo calculations show that with only 250 ppm of ^{157}Gd in tumor, neutron capture therapy can deliver 2,000 cGy to a tumor of 2 cm diameter or larger with 5 times 10^{12} n/cm ^2 fluence at the tumor. Dose measurements which were made with films and TLD's in phantoms verified these calculations. More extended Monte Carlo calculations demonstrate that neutron capture therapy with Gd possesses comparable dose distribution to B neutron capture therapy. With 5 times 10^{12 } n/cm^2 thermal neutrons at the tumor, Auger electrons from the Gd produced an optical density enhancement on the films that is similar to the effect caused by about 300 cGy of Gd prompt gamma dose which will further enhance the therapeutic effects. A technique that combines brachytherapy with Gd neutron capture therapy has been evaluated. Monte Carlo calculations show that 5,000 cGy of prompt gamma dose can be delivered to a treatment volume of 40 cm^3 with a 3-plane implant of a total of 9 Gd needles. The tumor to normal tissue advantage of this method is as good as ^{60} Co brachytherapy. Measurements of prompt gamma dose with films and TLD-700's in a lucite phantom verify the Monte Carlo evaluation. A technique which displays the Gd

  15. Synovectomy by Neutron capture

    International Nuclear Information System (INIS)

    The Synovectomy by Neutron capture has as purpose the treatment of the rheumatoid arthritis, illness which at present does not have a definitive curing. This therapy requires a neutron source for irradiating the articulation affected. The energy spectra and the intensity of these neutrons are fundamental since these neutrons induce nuclear reactions of capture with Boron-10 inside the articulation and the freely energy of these reactions is transferred at the productive tissue of synovial liquid, annihilating it. In this work it is presented the neutron spectra results obtained with moderator packings of spherical geometry which contains in its center a Pu239 Be source. The calculations were realized through Monte Carlo method. The moderators assayed were light water, heavy water base and the both combination of them. The spectra obtained, the average energy, the neutron total number by neutron emitted by source, the thermal neutron percentage and the dose equivalent allow us to suggest that the moderator packing more adequate is what has a light water thickness 0.5 cm (radius 2 cm) and 24.5 cm heavy water (radius 26.5 cm). (Author)

  16. Fast Edge-Searching and Related Problems

    Science.gov (United States)

    Yang, Boting

    Given a graph G = (V,E) in which a fugitive hides on vertices or along edges, graph searching problems are usually to find the minimum number of searchers required to capture the fugitive. In this paper, we consider the problem of finding the minimum number of steps to capture the fugitive. We introduce the fast edge-searching problem in the edge search model, which is the problem of finding the minimum number of steps (called the fast edge-search time) to capture the fugitive. We establish relations between the fast edge-search time and the fast search number. While the family of graphs whose fast search number is at most k is not minor-closed for any positive integer k ≥ 2, we show that the family of graphs whose fast edge-search time is at most k is minor-closed. We establish relations between the fast (edge-)searching and the node searching. These relations allow us to transform the problem of computing node search numbers to the problem of computing fast edge-search time or fast search numbers. Using these relations, we prove that the problem of deciding, given a graph G and an integer k, whether the fast (edge-)search number of G is less than or equal to k is NP-complete; and it remains NP-complete for Eulerian graphs. We also prove that the problem of determining whether the fast (edge-)search number of G is a half of the number of odd vertices in G is NP-complete; and it remains NP-complete for planar graphs with maximum degree 4. We present a linear time approximation algorithm for the fast edge-search time that always delivers solutions of at most (1+|V|-1/|E|+1) times the optimal value. This algorithm also gives us a tight upper bound on the fast search number of the graph. We also show a lower bound on the fast search number using the minimum degree and the number of odd vertices.

  17. Methods of Fast Exponentiation

    Directory of Open Access Journals (Sweden)

    Mohammed A. Maitah

    2010-01-01

    Full Text Available Problem statement: Modular exponentiation constitutes the basis of many well-known and widely used public key cryptosystems. Approach: A fast portable modular exponentiation algorithm considerably enhanced the speed and applicability of these systems, also an efficient implementation of this algorithm was the key to high performance of such system. Results: In this study, two main approaches for solving this problem were proposed. The proposed approaches involved calculations without usage of extra operational memory for saving constants and calculations with usage of preliminary calculated constants. Conclusion/Recommendations: The estimation of complexity of the speedup and effectiveness of proposed approaches for the data were presented.

  18. Accelerated Leadership Development: Fast Tracking School Leaders

    Science.gov (United States)

    Earley, Peter; Jones, Jeff

    2010-01-01

    "Accelerated Leadership Development" captures and communicates the lessons learned from successful fast-track leadership programmes in the private and public sector, and provides a model which schools can follow and customize as they plan their own leadership development strategies. As large numbers of headteachers and other senior staff retire,…

  19. First measurement of low intensity fast neutron background from rock at the Boulby Underground Laboratory

    CERN Document Server

    Tziaferi, E; Kudryavtsev, V A; Lerner, R; Lightfoot, P K; Paling, S M; Robinson, M; Spooner, N J C

    2006-01-01

    A technique to measure low intensity fast neutron flux has been developed. The design, calibrations, procedure for data analysis and interpretation of the results are discussed in detail. The technique has been applied to measure the neutron background from rock at the Boulby Underground Laboratory, a site used for dark matter and other experiments, requiring shielding from cosmic ray muons. The experiment was performed using a liquid scintillation detector. A 6.1 litre volume stainless steel cell was filled with an in-house made liquid scintillator loaded with Gd to enhance neutron capture. A two-pulse signature (proton recoils followed by gammas from neutron capture) was used to identify the neutron events from much larger gamma background from PMTs. Suppression of gammas from the rock was achieved by surrounding the detector with high-purity lead and copper. Calibrations of the detector were performed with various gamma and neutron sources. Special care was taken to eliminate PMT afterpulses and correlated...

  20. Capturing the Daylight Dividend

    Energy Technology Data Exchange (ETDEWEB)

    Peter Boyce; Claudia Hunter; Owen Howlett

    2006-04-30

    Capturing the Daylight Dividend conducted activities to build market demand for daylight as a means of improving indoor environmental quality, overcoming technological barriers to effective daylighting, and informing and assisting state and regional market transformation and resource acquisition program implementation efforts. The program clarified the benefits of daylight by examining whole building systems energy interactions between windows, lighting, heating, and air conditioning in daylit buildings, and daylighting's effect on the human circadian system and productivity. The project undertook work to advance photosensors, dimming systems, and ballasts, and provided technical training in specifying and operating daylighting controls in buildings. Future daylighting work is recommended in metric development, technology development, testing, training, education, and outreach.

  1. Robust automated knowledge capture.

    Energy Technology Data Exchange (ETDEWEB)

    Stevens-Adams, Susan Marie; Abbott, Robert G.; Forsythe, James Chris; Trumbo, Michael Christopher Stefan; Haass, Michael Joseph; Hendrickson, Stacey M. Langfitt

    2011-10-01

    This report summarizes research conducted through the Sandia National Laboratories Robust Automated Knowledge Capture Laboratory Directed Research and Development project. The objective of this project was to advance scientific understanding of the influence of individual cognitive attributes on decision making. The project has developed a quantitative model known as RumRunner that has proven effective in predicting the propensity of an individual to shift strategies on the basis of task and experience related parameters. Three separate studies are described which have validated the basic RumRunner model. This work provides a basis for better understanding human decision making in high consequent national security applications, and in particular, the individual characteristics that underlie adaptive thinking.

  2. Particle capture device

    Energy Technology Data Exchange (ETDEWEB)

    Jayne, John T.; Worsnop, Douglas R.

    2016-02-23

    In example embodiments, particle collection efficiency in aerosol analyzers and other particle measuring instruments is improved by a particle capture device that employs multiple collisions to decrease momentum of particles until the particles are collected (e.g., vaporized or come to rest). The particle collection device includes an aperture through which a focused particle beam enters. A collection enclosure is coupled to the aperture and has one or more internal surfaces against which particles of the focused beam collide. One or more features are employed in the collection enclosure to promote particles to collide multiple times within the enclosure, and thereby be vaporized or come to rest, rather than escape through the aperture.

  3. Analysis and simulation of photon scattering and neutron capture gamma spectra

    International Nuclear Information System (INIS)

    Within this thesis two twin experiments consisting of neutron capture and photon scattering on the neighbour isotopes 77Se/78Se and 195Pt/196Pt have been analysed to gain qualitative and quantitative information about the photon strength function and level density in the respective compound nuclei. For the analysis and simulation of both experimental types a new Monte Carlo simulation using a fast and efficient, extreme statistical treatment of radiative nuclear deexcitations, was developed. Furthermore the influence of fluctuations of transition widths on photon scattering were investigated and quantified. It could be shown that those lead to an enhancement of elastic scattering processes. The data analysis of both twin experiments reveals non-Lorentzian extra E1 photon strength below the neutron separation energy.

  4. Fast fabrication of Co3O4 and CuO/BiVO4 composite photocatalysts with high crystallinity and enhanced photocatalytic activity via ultrasound irradiation

    International Nuclear Information System (INIS)

    Research highlights: → Co3O4 and CuO/BiVO4 composite photocatalysts with good crystallinity were first developed by intense ultrasound irradiation method at room temperature. → The composite photocatalysts exhibited much higher visible light photocatalytic activity than that of pure BiVO4. → The formation of p-n heterojunction of Co3O4/BiVO4 or CuO/BiVO4 could enhance the separation of photogenerated hole-electron pairs. - Abstract: A facile and efficient approach for the fabrication of Co3O4 and CuO/BiVO4 composite photocatalysts was developed by intense ultrasound irradiation at room temperature. The as-synthesized samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), photoluminescence (PL) spectroscopy, UV-vis diffuse reflectance spectra (UV-vis DRS), and Brunauer-Emmett-Teller (BET) surface areas. The photocatalytic activity of the composite catalysts was evaluated by photocatalytic degradation of acid orange II under visible light (λ > 420 nm) irradiation. Results showed that under intense ultrasonic irradiation, the precursors of copper acetate and cobaltous acetate could transform into CuO and Co3O4, respectively and the amorphous BiVO4 can easily crystallize to highly crystalline BiVO4. The composite photocatalysts exhibited much higher photocatalytic activity than that of pure BiVO4. The enhanced photocatalytic performance could be attributed to the high crystallinity of BiVO4 and the formed p-n heterojunction of Co3O4/BiVO4 or CuO/BiVO4. These two factors can effectively suppress the recombination of photogenerated hole-electron pairs.

  5. Vortex-assisted surfactant-enhanced-emulsification liquid-liquid microextraction with solidification of floating organic droplet combined with flame atomic absorption spectrometry for the fast determination of cadmium in water samples.

    Science.gov (United States)

    Peng, Guilong; Lu, Ying; He, Qiang; Mmereki, Daniel; Tang, Xiaohui; Zhong, Zhihui; Zhao, Xiaolong

    2016-01-01

    A novel vortex-assisted surfactant-enhanced-emulsification liquid-liquid microextraction with solidification of floating organic droplet (VSLLME-SFO) was developed for the fast, simple and efficient determination of cadmium (Cd) in water samples followed by flame atomic absorption spectrometry (FAAS). In the VSLLME-SFO process, the addition of surfactant (as an emulsifier), could enhance the mass transfer from the aqueous solution into the extraction solvent. The extraction solvent could be dispersed into the aqueous phase under vigorous shaking with the vortex. In this paper, we investigated the influences of analytical parameters, including pH, extraction solvent type and its volume, surfactant type and its volume, concentration of chelating agent, salt effect and vortex time, on the extraction efficiency of Cd. Under the optimized conditions, the limit of detection was 0.16 μg/L. The analyte enrichment factor was 37.68. The relative standard deviation was 3.2% (10 μg/L, n = 10) and the calibration graph was linear, ranging from 0.5 to 30 μg/L. The proposed method was successfully applied for the analysis of ultra-trace Cd in river water and wastewater samples. PMID:27232416

  6. Fast and low-cost synthesis of 1D ZnO–TiO{sub 2} core–shell nanoarrays: Characterization and enhanced photo-electrochemical performance for water splitting

    Energy Technology Data Exchange (ETDEWEB)

    Hernández, Simelys, E-mail: simelys.hernandez@iit.it [Center for Space Human Robotics (IIT-POLITO), Istituto Italiano di Tecnologia, Corso Trento 21, 10129 Torino (Italy); Cauda, Valentina; Hidalgo, Diana; Farías Rivera, Vivian; Manfredi, Diego; Chiodoni, Angelica [Center for Space Human Robotics (IIT-POLITO), Istituto Italiano di Tecnologia, Corso Trento 21, 10129 Torino (Italy); Pirri, Fabrizio C. [Center for Space Human Robotics (IIT-POLITO), Istituto Italiano di Tecnologia, Corso Trento 21, 10129 Torino (Italy); Applied Science and Technology Department, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Torino (Italy)

    2014-12-05

    Highlights: • Simple, fast and low-cost synthesis of 1-D ZnO–TiO{sub 2} core–shell heterostructures. • ZnO NWs completely covered with a shell of anatase TiO{sub 2} nanocrystals in only 3 min. • The TiO{sub 2} shell thickness depends on the impregnation time in the titania synthesis bath. • 2-fold enhancement of photo-electrochemical activity and better stability of ZnONWs. • Forty- times higher photocurrent densities than TiO{sub 2} nanoparticles film. - Abstract: We report on a simple, fast and low-cost synthesis procedure for the complete covering of zinc oxide (ZnO) 1D nanostructures with a protective shell of titania (TiO{sub 2}) nanoparticles. ZnO nanowires (NWs) were grown on transparent F-doped Tin Oxide (FTO) conductive layer on glass by seed layer-assisted hydrothermal route in aqueous media, while the titania shell was deposited on the ZnO NWs through an in situ non-acid sol–gel synthesis. The nanowires impregnation time in the titania sol was varied from 3 to 10 min. The resulting core–shell ZnO–TiO{sub 2} structures were characterized by different techniques, including Scanning and Transmission Electron Microscopy, X-ray diffraction and UV–Vis spectroscopy, confirming the uniform coverage of the wurzite ZnO NWs with anatase TiO{sub 2} nanoparticles (NPs), with a shell thickness dependent on the impregnation time in the titania synthesis bath. Photoelectrochemical (PEC) tests of the ZnO–TiO{sub 2} material, used as anode for the water splitting reaction, confirmed the formation of the heterojunction by the enhanced photocurrent densities, reaching values of about 0.7 mA/cm{sup 2} under simulated solar light (AM1.5G, 100mW/cm{sup 2}). The core–shell photo-anodes performance was about twice and forty- times better than the ones with a film of equivalent thickness of bare ZnO NWs and TiO{sub 2} NPs, respectively. Steady-state measures of the photocurrent over the time and FESEM analysis confirmed that this procedure could be

  7. Fast and low-cost synthesis of 1D ZnO–TiO2 core–shell nanoarrays: Characterization and enhanced photo-electrochemical performance for water splitting

    International Nuclear Information System (INIS)

    Highlights: • Simple, fast and low-cost synthesis of 1-D ZnO–TiO2 core–shell heterostructures. • ZnO NWs completely covered with a shell of anatase TiO2 nanocrystals in only 3 min. • The TiO2 shell thickness depends on the impregnation time in the titania synthesis bath. • 2-fold enhancement of photo-electrochemical activity and better stability of ZnONWs. • Forty- times higher photocurrent densities than TiO2 nanoparticles film. - Abstract: We report on a simple, fast and low-cost synthesis procedure for the complete covering of zinc oxide (ZnO) 1D nanostructures with a protective shell of titania (TiO2) nanoparticles. ZnO nanowires (NWs) were grown on transparent F-doped Tin Oxide (FTO) conductive layer on glass by seed layer-assisted hydrothermal route in aqueous media, while the titania shell was deposited on the ZnO NWs through an in situ non-acid sol–gel synthesis. The nanowires impregnation time in the titania sol was varied from 3 to 10 min. The resulting core–shell ZnO–TiO2 structures were characterized by different techniques, including Scanning and Transmission Electron Microscopy, X-ray diffraction and UV–Vis spectroscopy, confirming the uniform coverage of the wurzite ZnO NWs with anatase TiO2 nanoparticles (NPs), with a shell thickness dependent on the impregnation time in the titania synthesis bath. Photoelectrochemical (PEC) tests of the ZnO–TiO2 material, used as anode for the water splitting reaction, confirmed the formation of the heterojunction by the enhanced photocurrent densities, reaching values of about 0.7 mA/cm2 under simulated solar light (AM1.5G, 100mW/cm2). The core–shell photo-anodes performance was about twice and forty- times better than the ones with a film of equivalent thickness of bare ZnO NWs and TiO2 NPs, respectively. Steady-state measures of the photocurrent over the time and FESEM analysis confirmed that this procedure could be effectively used to both protect the nanostructured ZnO from photo

  8. Fast preparation of Bi2GeO5 nanoflakes via a microwave-hydrothermal process and enhanced photocatalytic activity after loading with Ag nanoparticles

    International Nuclear Information System (INIS)

    Highlights: ► Bi2GeO5 nanoflakes were successfully synthesized via a microwave-assisted solution-phase approach. ► Ag nanoparticles were deposited on the Bi2GeO5 nanoflakes by a photoreduction procedure. ► Catalytic activity of the Ag/Bi2GeO5 nanocomposite in the photo-degradation of rhodamine B (RhB) was much higher than that of pure Bi2GeO5. -- Abstract: In this work, a facile and rapid microwave-assisted hydrothermal route has been developed to prepare Bi2GeO5 nanoflakes. Ag nanoparticles were subsequently deposited on the Bi2GeO5 nanoflakes by a photoreduction procedure. The phases and morphologies of the products were characterized by powder X-ray diffraction (XRD), X-ray photoelectron spectrum (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and UV–vis diffuse reflectance spectroscopy. Photocatalytic experiments indicate that such Ag/Bi2GeO5 nanocomposite possesses higher photocatalytic activity for RhB degradation under UV light irradiation in comparison to pure Bi2GeO5. The amount of Ag in the nanocomposite affects the catalytic activity, and 3 wt% Ag showed the highest photodegradation efficiency. Moreover, the catalyst remains active after four consecutive tests. The present study provides a new strategy to design composite materials with enhanced photocatalytic activity.

  9. FAST DISSOLVING TABLETS: AN UPDATE

    Directory of Open Access Journals (Sweden)

    Darna Bikshapathi

    2011-06-01

    Full Text Available Fast dissolving tablets are dissolving rapidly in the saliva without the need for water. Some tablets are designed to dissolve in saliva remarkably fast, within a few seconds, and are true fast-dissolving tablets. Other ingredients to enhance the rate of tablet disintegration in the oral cavity, and are more appropriately termed fast-disintegrating tablets, as they may take up to a minute to completely disintegrate. Fast or mouth dissolving tablets have been formulated for pediatric, geriatric, and bedridden patients and for active patients who are busy and traveling and may not have access to water. Fast dissolving tablets (FDTs have received ever-increasing demand during the last decade, and the field has become a rapidly growing area in the pharmaceutical industry. This article describes various formulations and technologies developed to achieve fast dissolution/dispersion of tablets in the oral cavity. In this review describes in detail about FDT technologies based on lyophilization, molding, sublimation, spray drying, mass extrusion and direct compression. Several techniques have been developed in the recent past, to improve the disintegration quality of these delicate dosage forms without affecting their integrity. This article focuses on the technologies available and the advances made so far in the field of fabrication of fast dissolving tablets. Apart from the conventional methods of fabrication, this review also provides the detailed concept of some unique patented technologies like Zydis, Orasolv, Durasolv, Flashtab, Flash dose and Wowtab, Lyoc, Pharmaburst technology, Frosta technology, OraQuick, Quick-Dis Technology, Sheaform Technology, Ceform Technology, Nano technology, Advatab.Fast dissolving, Patented technologies, Sudisintegrants, Evaluation techn

  10. Fast N-body Simulations on GPUs

    CERN Document Server

    Yokota, Rio

    2011-01-01

    With the current hybridization of treecodes and FMMs, combined with auto-tuning capabilities on heterogeneous architectures, the flexibility of fast N -body methods has been greatly enhanced. These features are a requirement to developing a black- box software library for fast N-body algorithms on heterogeneous systems, which is our immediate goal.

  11. Lunar Sulfur Capture System

    Science.gov (United States)

    Berggren, Mark; Zubrin, Robert; Bostwick-White, Emily

    2013-01-01

    The Lunar Sulfur Capture System (LSCS) protects in situ resource utilization (ISRU) hardware from corrosion, and reduces contaminant levels in water condensed for electrolysis. The LSCS uses a lunar soil sorbent to trap over 98 percent of sulfur gases and about two-thirds of halide gases evolved during hydrogen reduction of lunar soils. LSCS soil sorbent is based on lunar minerals containing iron and calcium compounds that trap sulfur and halide gas contaminants in a fixed-bed reactor held at temperatures between 250 and 400 C, allowing moisture produced during reduction to pass through in vapor phase. Small amounts of Earth-based polishing sorbents consisting of zinc oxide and sodium aluminate are used to reduce contaminant concentrations to one ppm or less. The preferred LSCS configuration employs lunar soil beneficiation to boost concentrations of reactive sorbent minerals. Lunar soils contain sulfur in concentrations of about 0.1 percent, and halogen compounds including chlorine and fluorine in concentrations of about 0.01 percent. These contaminants are released as gases such as H2S, COS, CS2,HCl, and HF during thermal ISRU processing with hydrogen or other reducing gases. Removal of contaminant gases is required during ISRU processing to prevent hardware corrosion, electrolyzer damage, and catalyst poisoning. The use of Earth-supplied, single-use consumables to entirely remove contaminants at the levels existing in lunar soils would make many ISRU processes unattractive due to the large mass of consumables relative to the mass of oxygen produced. The LSCS concept of using a primary sorbent prepared from lunar soil was identified as a method by which the majority of contaminants could be removed from process gas streams, thereby substantially reducing the required mass of Earth-supplied consumables. The LSCS takes advantage of minerals containing iron and calcium compounds that are present in lunar soil to trap sulfur and halide gases in a fixedbed reactor

  12. Neutron Capture and Neutron Halos

    OpenAIRE

    A.Mengoni; Otsuka, T; Nakamura, T.(International Center for Elementary Particle Physics and Department of Physics, The University of Tokyo, Tokyo, Japan); Ishihara, M.

    1996-01-01

    The connection between the neutron halo observed in light neutron rich nuclei and the neutron radiative capture process is outlined. We show how nuclear structure information such as spectroscopic factors and external components of the radial wave function of loosely bound states can be derived from the neutron capture cross section. The link between the direct radiative capture and the Coulomb dissociation process is elucidated.

  13. Resource capture by single leaves

    Energy Technology Data Exchange (ETDEWEB)

    Long, S.P.

    1992-05-01

    Leaves show a variety of strategies for maximizing CO{sub 2} and light capture. These are more meaningfully explained if they are considered in the context of maximizing capture relative to the utilization of water, nutrients and carbohydrates reserves. There is considerable variation between crops in their efficiency of CO{sub 2} and light capture at the leaf level. Understanding of these mechanisms indicate some ways in which efficiency of resource capture could be level cannot be meaningfully considered without simultaneous understanding of implications at the canopy level. 36 refs., 5 figs., 1 tab.

  14. Neutron capture therapy

    International Nuclear Information System (INIS)

    The overall state of the art related with neutron capture therapy(NCT) is surveyed. Since the field related with NCT is very wide, it is not intended to survey all related subjects in depth. The primary objective of this report is to help those working for the installation of a NCT facility and a PGNAA(prompt gamma ray neutron activation analysis) system for the boron analysis understand overall NCT at Hanaro. Therefore, while the parts of reactor neutron source and PGNAA are dealt in detail, other parts are limited to the level necessary to understand related fields. For example, the subject of chemical compound which requires intensive knowledge on chemistry, is not dealt as a separated item. However, the requirement of a compound for NCT, currently available compounds, their characteristics, etc. could be understood through this report. Although the subject of cancer treated by NCT is out of the capability of the author, it is dealt focussing its characteristics related with the success of NCT. Each detailed subject is expected to be dealt more detail by specialists in future. This report would be helpful for the researchers working for the NCT to understand related fields. (author). 128 refs., 3 tabs., 12 figs

  15. Sub-barrier capture with quantum diffusion approach

    Directory of Open Access Journals (Sweden)

    Scheid W.

    2011-10-01

    Full Text Available With the quantum diffusion approach the behavior of capture cross sections and mean-square angular momenta of captured systems are revealed in the reactions with deformed and spherical nuclei at sub-barrier energies. With decreasing bombarding energy under the barrier the external turning point of the nucleus-nucleus potential leaves the region of short-range nuclear interaction and action of friction. Because of this change of the regime of interaction, an unexpected enhancement of the capture cross section is found at bombarding energies far below the Coulomb barrier. This effect is shown its worth in the dependence of mean-square angular momentum on the bombarding energy. From the comparison of calculated capture cross sections and experimental capture or fusion cross sections the importance of quasifission near the entrance channel is demonstrated for the actinidebased reactions and reactions with medium-heavy nuclei at extreme sub-barrier energies.

  16. Capturing the Coma

    Science.gov (United States)

    2005-01-01

    This image shows comet Tempel 1, as seen by the Deep Impact spacecraft on June 21, 2005. It was taken using the clear filter of the spacecraft's medium resolution imager camera. The spacecraft was 11,564,081.7 kilometers (7,185,920 miles) away from the comet. Twelve images were combined together, and a logarithmic stretch was applied to enhance the coma of the comet.

  17. Fast and highly sensitive fiber-enhanced Raman spectroscopic monitoring of molecular H2 and CH4 for point-of-care diagnosis of malabsorption disorders in exhaled human breath.

    Science.gov (United States)

    Hanf, Stefan; Bögözi, Timea; Keiner, Robert; Frosch, Torsten; Popp, Jürgen

    2015-01-20

    Breath gas analysis is a novel powerful technique for noninvasive, early-stage diagnosis of metabolic disorders or diseases. Molecular hydrogen and methane are biomarkers for colonic fermentation, because of malabsorption of oligosaccharides (e.g., lactose or fructose) and for small intestinal bacterial overgrowth. Recently, the presence of these gases in exhaled breath was also correlated with obesity. Here, we report on the highly selective and sensitive detection of molecular hydrogen and methane within a complex gas mixture (consisting of H2, CH4, N2, O2, and CO2) by means of fiber-enhanced Raman spectroscopy (FERS). An elaborate FERS setup with a microstructured hollow core photonic crystal fiber (HCPCF) provided a highly improved analytical sensitivity. The simultaneous monitoring of H2 with all other gases was achieved by a combination of rotational (H2) and vibrational (other gases) Raman spectroscopy within the limited spectral transmission range of the HCPCF. The HCPCF was combined with an adjustable image-plane aperture pinhole, in order to separate the H2 rotational Raman bands from the silica background signal and improve the sensitivity down to a limit of detection (LOD) of 4.7 ppm (for only 26 fmol H2). The ability to monitor the levels of H2 and CH4 in a positive hydrogen breath test (HBT) was demonstrated. The FERS sensor possesses a high dynamic range (∼5 orders of magnitude) with a fast response time of few seconds and provides great potential for miniaturization. We foresee that this technique will pave the way for fast, noninvasive, and painless point-of-care diagnosis of metabolic diseases in exhaled human breath. PMID:25545503

  18. Fast food tips

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/patientinstructions/000105.htm Fast food tips To use the sharing features on this ... fast food. When You Go to a Fast Food Restaurant Knowing the amount of calories, fat, and ...

  19. A vareity of Hg capture solutions are available

    Energy Technology Data Exchange (ETDEWEB)

    Blankinship, S.

    2009-06-15

    While vacating the Clean Air Mercury Rule (CAMR) has postponed implementation of capturing mercury emitted by coal-fired power plants improvements in ways to capture and monitor mercury have continued. One method of enhancing Hg capture from FGD and SCR is to treat the coal by adding a halogen, such as calcium bromide in Alstom's KNX process prior to combustion. Power plants without FGD usually use sorbent injection, mostly an activated carbon, upstream of a particulate control device. 1 fig.

  20. Thomas-forbidden particle capture

    OpenAIRE

    Carter, John H.; Lieber, Michael

    2010-01-01

    At high energies, in particle-capture processes between ions and atoms, classical kinematic requirements show that generally double collision Thomas processes dominate. However, for certain mass-ratios these processes are kinematically forbidden. This paper explores the possibility of capture for such processes by triple or higher order collision processes.

  1. FAST: FAST Analysis of Sequences Toolbox

    Directory of Open Access Journals (Sweden)

    Travis J. Lawrence

    2015-05-01

    Full Text Available FAST (FAST Analysis of Sequences Toolbox provides simple, powerful open source command-line tools to filter, transform, annotate and analyze biological sequence data. Modeled after the GNU (GNU’s Not Unix Textutils such as grep, cut, and tr, FAST tools such as fasgrep, fascut, and fastr make it easy to rapidly prototype expressive bioinformatic workflows in a compact and generic command vocabulary. Compact combinatorial encoding of data workflows with FAST commands can simplify the documentation and reproducibility of bioinformatic protocols, supporting better transparency in biological data science. Interface self-consistency and conformity with conventions of GNU, Matlab, Perl, BioPerl, R and GenBank help make FAST easy and rewarding to learn. FAST automates numerical, taxonomic, and text-based sorting, selection and transformation of sequence records and alignment sites based on content, index ranges, descriptive tags, annotated features, and in-line calculated analytics, including composition and codon usage. Automated content- and feature-based extraction of sites and support for molecular population genetic statistics makes FAST useful for molecular evolutionary analysis. FAST is portable, easy to install and secure thanks to the relative maturity of its Perl and BioPerl foundations, with stable releases posted to CPAN. Development as well as a publicly accessible Cookbook and Wiki are available on the FAST GitHub repository at https://github.com/tlawrence3/FAST. The default data exchange format in FAST is Multi-FastA (specifically, a restriction of BioPerl FastA format. Sanger and Illumina 1.8+ FastQ formatted files are also supported. FAST makes it easier for non-programmer biologists to interactively investigate and control biological data at the speed of thought.

  2. Neutron Induced Capture and Fission Processes on 238U

    OpenAIRE

    Oprea Cristiana; Oprea Alexandru

    2016-01-01

    Nuclear data on Uranium isotopes are of crucial interest for new generation of nuclear reactors. Processes of interest are the nuclear reactions induced by neutrons and in this work mainly the capture and the fission process on 238U will be analyzed in a wide energy interval. For slow and resonant neutrons the many levels Breit – Wigner formalism is necessary. In the case of fast and very fast neutrons up to 200 MeV the nuclear reaction mechanism implemented in Talys will be used. The present...

  3. Neutron capture reactions at DANCE

    International Nuclear Information System (INIS)

    The Detector for Advanced Neutron Capture Experiments (DANCE) is a 4π BaF2 array consisting of 160 active detector elements. The primary purpose of the array is to perform neutron capture cross section measurements on small (> or approx.100 μg) and/or radioactive (241,243Am, neutron capture and neutron-induced fission cross sections and capture-to-fission ratio (α = σγ/σf) for 235U using a new fission-tagging detector as well as neutron capture cross sections for several astrophysics branch-point nuclei. Results from several of these measurements will be presented along with a discussion of additional physics information that can be extracted from the DANCE data

  4. Fast Fuzzy Arithmetic Operations

    Science.gov (United States)

    Hampton, Michael; Kosheleva, Olga

    1997-01-01

    In engineering applications of fuzzy logic, the main goal is not to simulate the way the experts really think, but to come up with a good engineering solution that would (ideally) be better than the expert's control, In such applications, it makes perfect sense to restrict ourselves to simplified approximate expressions for membership functions. If we need to perform arithmetic operations with the resulting fuzzy numbers, then we can use simple and fast algorithms that are known for operations with simple membership functions. In other applications, especially the ones that are related to humanities, simulating experts is one of the main goals. In such applications, we must use membership functions that capture every nuance of the expert's opinion; these functions are therefore complicated, and fuzzy arithmetic operations with the corresponding fuzzy numbers become a computational problem. In this paper, we design a new algorithm for performing such operations. This algorithm is applicable in the case when negative logarithms - log(u(x)) of membership functions u(x) are convex, and reduces computation time from O(n(exp 2))to O(n log(n)) (where n is the number of points x at which we know the membership functions u(x)).

  5. Neutron Induced Capture and Fission Processes on 238U

    Directory of Open Access Journals (Sweden)

    Oprea Cristiana

    2016-01-01

    Full Text Available Nuclear data on Uranium isotopes are of crucial interest for new generation of nuclear reactors. Processes of interest are the nuclear reactions induced by neutrons and in this work mainly the capture and the fission process on 238U will be analyzed in a wide energy interval. For slow and resonant neutrons the many levels Breit – Wigner formalism is necessary. In the case of fast and very fast neutrons up to 200 MeV the nuclear reaction mechanism implemented in Talys will be used. The present evaluations are necessary in order to obtain the field of neutrons in the design of nuclear reactors and they are compared with experimental data from literature obtained from capture and (n,xn processes.

  6. Neutron Induced Capture and Fission Processes on 238U

    Science.gov (United States)

    Oprea, Cristiana; Oprea, Alexandru

    2016-03-01

    Nuclear data on Uranium isotopes are of crucial interest for new generation of nuclear reactors. Processes of interest are the nuclear reactions induced by neutrons and in this work mainly the capture and the fission process on 238U will be analyzed in a wide energy interval. For slow and resonant neutrons the many levels Breit - Wigner formalism is necessary. In the case of fast and very fast neutrons up to 200 MeV the nuclear reaction mechanism implemented in Talys will be used. The present evaluations are necessary in order to obtain the field of neutrons in the design of nuclear reactors and they are compared with experimental data from literature obtained from capture and (n,xn) processes.

  7. Materials For Gas Capture, Methods Of Making Materials For Gas Capture, And Methods Of Capturing Gas

    KAUST Repository

    Polshettiwar, Vivek

    2013-06-20

    In accordance with the purpose(s) of the present disclosure, as embodied and broadly described herein, embodiments of the present disclosure, in one aspect, relate to materials that can be used for gas (e.g., CO.sub.2) capture, methods of making materials, methods of capturing gas (e.g., CO.sub.2), and the like, and the like.

  8. Evaluation of absorbed dose in Gadolinium neutron capture therapy

    OpenAIRE

    Abdullaeva Gayane; Djuraeva Gulnara; Kim Andrey; Koblik Yuriy; Kulabdullaev Gairatulla; Rakhmonov Turdimukhammad; Saytjanov Shavkat

    2015-01-01

    Gadolinium neutron capture therapy (GdNCT) is used for treatment of radioresistant malignant tumors. The absorbed dose in GdNCT can be divided into four primary dose components: thermal neutron, fast neutron, photon and natural gadolinium doses. The most significant is the dose created by natural gadolinium. The amount of gadolinium at the irradiated region is changeable and depends on the gadolinium delivery agent and on the structure of the location where the agent i...

  9. Electron capture and stellar collapse

    International Nuclear Information System (INIS)

    In order, to investigate the function of electron capture in the phenomenon of pre-supernovae gravitacional collapse, an hydrodynamic caculation was carried out, coupling capture, decay and nuclear reaction equation system. A star simplified model (homogeneous model) was adopted using fermi ideal gas approximation for tthe sea of free electrons and neutrons. The non simplified treatment from quasi-static evolution to collapse is presented. The capture and beta decay rates, as wellas neutron delayed emission, were calculated by beta decay crude theory, while the other reaction rates were determined by usual theories. The preliminary results are presented. (M.C.K.)

  10. Fast Flow Cavity Enhanced Ozone Monitor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Naturally occurring in the stratosphere, ozone plays a significant role in many atmospheric reactions, cloud formation, and is the key player in shielding harmful...

  11. Fast Feedback System for CEBAF

    Energy Technology Data Exchange (ETDEWEB)

    M.P. Chowdhary; G.A. Krafft; H. Shoaee; W.A. Watson III

    1995-10-01

    A fast feedback system based on concepts of modern control theory has been implemented in the CEBAF Control System to stabilize various machine parameters. The continuous wave operation of CEBAF requires that parameters such as beam energy and position are stabilized against fast fluctuations. The beam energy must be stabilized against fast gradient and phase fluctuations in the RF accelerating system. This fast feedback system currently operates at 60 Hz rate and is integrated with EPICS. The mathematical model of the system for various feedback loops is expressed in state space formalism. The design of control law and simulation of closed-loop system response is performed using MatlabTM and SimulinkTM. This paper describes the process of designing control algorithms, implementation of the fast feedback system and operational experience with this system at CEBAF. The performance of this feedback system, while operating at much higher rates with high closed loop gain, can be enhanced by continually performing on-line identification of the system from the input and output data. System identification is the process of developing or improving an analytically derived mathematical representation of a physical system using experimental data. The current status of this feature is presented.

  12. Lunar Sulfur Capture System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Lunar Sulfur Capture System (LSCS) is an innovative method to recover sulfur compounds from lunar soil using sorbents derived primarily from in-situ resources....

  13. Porous Organic Polymers for CO2 Capture

    KAUST Repository

    Teng, Baiyang

    2013-05-01

    Carbon dioxide (CO2) has long been regarded as the major greenhouse gas, which leads to numerous negative effects on global environment. The capture and separation of CO2 by selective adsorption using porous materials proves to be an effective way to reduce the emission of CO2 to atmosphere. Porous organic polymers (POPs) are promising candidates for this application due to their readily tunable textual properties and surface functionalities. The objective of this thesis work is to develop new POPs with high CO2 adsorption capacities and CO2/N2 selectivities for post-combustion effluent (e.g. flue gas) treatment. We will also exploit the correlation between the CO2 capture performance of POPs and their textual properties/functionalities. Chapters Two focuses on the study of a group of porous phenolic-aldehyde polymers (PPAPs) synthesized by a catalyst-free method, the CO2 capture capacities of these PPAPs exceed 2.0 mmol/g at 298 K and 1 bar, while keeping CO2/N2 selectivity of more than 30 at the same time. Chapter Three reports the gas adsorption results of different hyper-cross-linked polymers (HCPs), which indicate that heterocyclo aromatic monomers can greatly enhance polymers’ CO2/N2 selectivities, and the N-H bond is proved to the active CO2 adsorption center in the N-contained (e.g. pyrrole) HCPs, which possess the highest selectivities of more than 40 at 273 K when compared with other HCPs. Chapter Four emphasizes on the chemical modification of a new designed polymer of intrinsic microporosity (PIM) with high CO2/N2 selectivity (50 at 273 K), whose experimental repeatability and chemical stability prove excellent. In Chapter Five, we demonstrate an improvement of both CO2 capture capacity and CO2/N2 selectivity by doping alkali metal ions into azo-polymers, which leads a promising method to the design of new porous organic polymers.

  14. Value Capture for Transportation Finance

    OpenAIRE

    Zhirong (Jerry) Zhao; Michael Iacono; David Levinson

    2009-01-01

    As vehicles become more fuel-efficient and overall levels of travel stagnate in response to increases in fuel prices, conventional sources of revenue for transportation finance such as taxes on motor fuels have been put under increasing pressure. One potential replacement as a source of revenue is a set of policies collectively referred to as value capture policies. In contrast to fuel taxes and other instruments that impose charges on users of transportation networks, value capture policies ...

  15. Toward transformational carbon capture systems

    Energy Technology Data Exchange (ETDEWEB)

    Miller, David C. [National Energy Technology Laboratory, U.S. Dept. of Energy, Pittsburgh PA (United States); Litynski, John T. [Office of Fossil Energy, U.S. Dept. of Energy, Washington DC (United States); Brickett, Lynn A. [National Energy Technology Laboratory, U.S. Dept. of Energy, Pittsburgh PA (United States); Morreale, Bryan D. [National Energy Technology Laboratory, U.S. Dept. of Energy, Pittsburgh PA (United States)

    2015-10-28

    This paper will briefly review the history and current state of Carbon Capture and Storage (CCS) research and development and describe the technical barriers to carbon capture. it will argue forcefully for a new approach to R&D, which leverages both simulation and physical systems at the laboratory and pilot scales to more rapidly move the best technoogies forward, prune less advantageous approaches, and simultaneously develop materials and processes.

  16. Direct Capture at Low Energies

    OpenAIRE

    Balogh, W.; Bieber, R.; Oberhummer, H.; Rauscher, T.; Kratz, K.-L.; Mohr, P; Staudt, G.; Sharma, M. M.

    1994-01-01

    The importance of direct capture for (n,$\\gamma$)--reactions on intermediate-- and heavy--mass target nuclei occuring in the s-- and r--process is investigated. It is shown that the direct mechanism is non--negligible for magic and neutron rich target nuclei. For some double magic and neutron rich nuclei in the r--process direct capture is even the dominant reaction mechanism.

  17. Context Capture in Software Development

    OpenAIRE

    Antunes, Bruno; Correia, Francisco; Gomes, Paulo

    2011-01-01

    The context of a software developer is something hard to define and capture, as it represents a complex network of elements across different dimensions that are not limited to the work developed on an IDE. We propose the definition of a software developer context model that takes into account all the dimensions that characterize the work environment of the developer. We are especially focused on what the software developer context encompasses at the project level and how it can be captured. T...

  18. Fast-neutron interaction with niobium

    International Nuclear Information System (INIS)

    Results of a comprehensive study of the interaction of fast neutrons with niobium are presented, including measurement and interpretation of neutron total, differential-scattering and radiative-capture cross sections. The experimental results are interpreted in the context of the optical-statistical model, with attention to the Fermi-surface anomaly. Experimental results, physical interpretations and rigorous statistical methods are used to provide a comprehensive evaluated nuclear data file suitable for use in a wide range of applied neutronic calculations

  19. Capture reactions at low energies

    International Nuclear Information System (INIS)

    Some few body capture reaction studies at low energies are reviewed. The emphasis is on the use of polarized beams. New calculations of n+d and p+d capture had just recently been completed by the Los Alamos group (Friar, Gibson, and Payne). Their results are in good agreement with existing data, and emphasize the importance of meson exchange current effects in these processes at thermal energies. The effects of M1 radiation can be seen in the vector analyzing power of the p+d radiative capture reaction from its interference with E1 radiation. The vector analyzing powers of the rvec p+T → 4He + γ reaction can be used to search for M1 radiation in 4He. Low energy data show a substantial b1 coefficient which can only be accounted for with a substantial M1 contribution. The author is also working on studying the rvec d+T and rvec d+3He capture reactions in the region of the fusion resonance. His (published) rvec d+T capture data indicate that the reaction goes via ∼95% S = 3/2, E1 capture with small S = 1/2, E1 and small M1 admixtures. In the course of obtaining the d+T and d+3He data, he realized that he could use his spectra to obtain the ground state widths of 5He and 5Li. Finally, he will discuss the d+d reaction at very low energies. The simplest picture of this reaction dominated by S wave capture to the D-state below 1 MeV

  20. Boron neutron capture irradiation: setting up a clinical programme in Nice; Irradiation par capture de neutrons: mise en place d`un programme clinique a Nice

    Energy Technology Data Exchange (ETDEWEB)

    Pignol, J.P.; Chauvel, P.; Courdi, A.; Iborra-Brassart, N.; Frenay, M.; Herault, J.; Bensadoun, R.J.; Milano, G.; Demard, F. [Centre de Lutte Contre le Cancer Antoine Lacassagne, 06 - Nice (France); Paquis, P.; Lonjon, M.; Lebrun-Frenay, C.; Grellier, P.; Chatel, M. [Hopital Pasteur, 06 - Nice (France); Nepveu, F.; Patau, J.P. [Toulouse-3 Univ., 31 (France); Breteau, N. [Hopital de la Source, 45 - Orleans (France)

    1996-12-31

    Neutron capture irradiation aims to selectively destroy tumor tumor cell using {sup 10}B(n,{alpha}){sup 7}Li nuclear reactions produced within themselves. Following the capture reaction, an {alpha} particle and a, {sup 7}Li ion are emitted. Carrying an energy of 2.79 MeV, they destroy all molecular structures along their path close to 10 {mu}m. These captures, used exclusively with a `slow` neutron irradiation, provide a neutron capture therapy (BNCT). If they are used in addition to a fast neutron beam irradiation, they provide a neutron capture potentiation (NCP). The Centre Antoine-Lacassagne in Nice is actively involved in the European Demonstration project for BNCT of grade IV glioblastomas (GBM) after surgical excision and BSH administration. Taking into account the preliminary results obtained in Japan, work on an `epithermal` neutron target compatible with various cyclotron beams is in progress to facilitate further developments of this technique. For NCP, thermalized neutron yield has been measured in phantoms irradiated in the fast neutron beam of the biomedical cyclotron in Nice. A thermal peak appears after 5 cm depth in the tissues, delayed after the fast neutron peak at 1.8 cm depth. Thus, a physical overdosage of 10 % may be obtained if 100 ppm of {sup 10}B are assumed in the tissues. Our results using CAL 58 GBM cell line demonstrate a dose modification factor (DMF) of 1.19 when 100 ppm of boric acid are added to the growth medium. Thus for the particles, issued from neutron capture, a biological efficiency at least twice that of fast neutrons can be derived. These results, compared with historical data on fast neutron irradiation of glioblastoma, suggest that a therapeutic window may be obtained for GBM. (author). 26 refs.

  1. Feasibility evaluation of neutron capture therapy for hepatocellular carcinoma using selective enhancement of boron accumulation in tumour with intra-arterial administration of boron-entrapped water-in-oil-in-water emulsion

    International Nuclear Information System (INIS)

    Introduction: Hepatocellular carcinoma (HCC) is one of the most difficult to cure with surgery, chemotherapy, or other combinational therapies. In the treatment of HCC, only 30% patients can be operated due to complication of liver cirrhosis or multiple intrahepatic tumours. Tumour cell destruction in boron neutron-capture therapy (BNCT) is due to the nuclear reaction between 10B atoms and thermal neutrons, so it is necessary to accumulate a sufficient quantity of 10B atoms in tumour cells for effective tumour cell destruction by BNCT. Water-in-oil-in-water (WOW) emulsion has been used as the carrier of anti-cancer agents on intra-arterial injections in clinical. In this study, we prepared 10BSH entrapped WOW emulsion by double emulsifying technique using iodized poppy-seed oil (IPSO), 10BSH and surfactant, for selective intra-arterial infusion to HCC, and performed simulations of the irradiation in order to calculate the dose delivered to the patients. Materials and methods: WOW emulsion was administrated with intra-arterial injections via proper hepatic artery on VX-2 rabbit hepatic tumour models. We simulated the irradiation of epithermal neutron and calculated the dose delivered to the tissues with JAEA computational dosimetry system (JCDS) at JRR4 reactor of Japan Atomic Research Institute, using the CT scans of a HCC patient. Results and discussions: The 10B concentrations in VX-2 tumour obtained by delivery with WOW emulsion were superior to those by conventional IPSO mix emulsion. According to the rabbit model, the boron concentrations (ppm) in tumour, normal liver tissue, and blood are 61.7, 4.3, and 0.1, respectively. The results of the simulations show that normal liver biologically weighted dose is restricted to 4.9 Gy-Eq (CBE; liver tumour: 2.5, normal liver: 0.94); the maximum, minimum, and mean tumour weighted dose are 43.1, 7.3, and 21.8 Gy-Eq, respectively, in 40 min irradiation. In this study, we show that 10B entrapped WOW emulsion could be

  2. Feasibility evaluation of neutron capture therapy for hepatocellular carcinoma using selective enhancement of boron accumulation in tumour with intra-arterial administration of boron-entrapped water-in-oil-in-water emulsion

    Energy Technology Data Exchange (ETDEWEB)

    Yanagie, Hironobu, E-mail: yanagie@n.t.u-tokyo.ac.jp [Dept of Nuclear Engineering and Management, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)] [Cooperative Unit of Medicine and Engineering, University of Tokyo Hospital, Tokyo (Japan); Kumada, Hiroaki [Proton Medical Research Center, University of Tsukuba, Ibaraki (Japan); Nakamura, Takemi [Japan Atomic Energy Research Institute, Ibaraki (Japan); Higashi, Syushi [Dept of Surgery, Ebihara Memorial Hospital, Miyazaki (Japan)] [Kyushu Industrial Sources Foundation, Miyazaki (Japan); Ikushima, Ichiro [Dept of Radiology, Miyakonojyo Metropolitan Hospital, Miyazaki (Japan); Morishita, Yasuyuki [Dept of Human and Molecular Pathology, Graduate School of Medicine, University of Tokyo, Tokyo (Japan); Shinohara, Atsuko [Dept of Humanities, Graduate School of Seisen University, Tokyo (Japan); Fijihara, Mitsuteru [SPG Techno Ltd. Co., Miyazaki (Japan); Suzuki, Minoru; Sakurai, Yoshinori [Research Reactor Institute, Kyoto University, Osaka (Japan); Sugiyama, Hirotaka [Cooperative Unit of Medicine and Engineering, University of Tokyo Hospital, Tokyo (Japan); Kajiyama, Tetsuya [Kyushu Industrial Sources Foundation, Miyazaki (Japan); Nishimura, Ryohei [Dept of Veternary Surgery, University of Tokyo Veternary Hospital, Tokyo (Japan); Ono, Koji [Research Reactor Institute, Kyoto University, Osaka (Japan); Nakajima, Jun; Ono, Minoru [Dept of Cardiothracic Surgery, University of Tokyo Hospital, Tokyo (Japan); Eriguchi, Masazumi [Cooperative Unit of Medicine and Engineering, University of Tokyo Hospital, Tokyo (Japan)] [Department of Surgery, Shin-Yamanote Hospital, Saitama (Japan); Takahashi, Hiroyuki [Dept of Nuclear Engineering and Management, Graduate School of Engineering, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)] [Cooperative Unit of Medicine and Engineering, University of Tokyo Hospital, Tokyo (Japan)

    2011-12-15

    Introduction: Hepatocellular carcinoma (HCC) is one of the most difficult to cure with surgery, chemotherapy, or other combinational therapies. In the treatment of HCC, only 30% patients can be operated due to complication of liver cirrhosis or multiple intrahepatic tumours. Tumour cell destruction in boron neutron-capture therapy (BNCT) is due to the nuclear reaction between {sup 10}B atoms and thermal neutrons, so it is necessary to accumulate a sufficient quantity of {sup 10}B atoms in tumour cells for effective tumour cell destruction by BNCT. Water-in-oil-in-water (WOW) emulsion has been used as the carrier of anti-cancer agents on intra-arterial injections in clinical. In this study, we prepared {sup 10}BSH entrapped WOW emulsion by double emulsifying technique using iodized poppy-seed oil (IPSO), {sup 10}BSH and surfactant, for selective intra-arterial infusion to HCC, and performed simulations of the irradiation in order to calculate the dose delivered to the patients. Materials and methods: WOW emulsion was administrated with intra-arterial injections via proper hepatic artery on VX-2 rabbit hepatic tumour models. We simulated the irradiation of epithermal neutron and calculated the dose delivered to the tissues with JAEA computational dosimetry system (JCDS) at JRR4 reactor of Japan Atomic Research Institute, using the CT scans of a HCC patient. Results and discussions: The {sup 10}B concentrations in VX-2 tumour obtained by delivery with WOW emulsion were superior to those by conventional IPSO mix emulsion. According to the rabbit model, the boron concentrations (ppm) in tumour, normal liver tissue, and blood are 61.7, 4.3, and 0.1, respectively. The results of the simulations show that normal liver biologically weighted dose is restricted to 4.9 Gy-Eq (CBE; liver tumour: 2.5, normal liver: 0.94); the maximum, minimum, and mean tumour weighted dose are 43.1, 7.3, and 21.8 Gy-Eq, respectively, in 40 min irradiation. In this study, we show that {sup 10}B

  3. CHAOTIC CAPTURE OF NEPTUNE TROJANS

    International Nuclear Information System (INIS)

    Neptune Trojans (NTs) are swarms of outer solar system objects that lead/trail planet Neptune during its revolutions around the Sun. Observations indicate that NTs form a thick cloud of objects with a population perhaps ∼10 times more numerous than that of Jupiter Trojans and orbital inclinations reaching ∼25 deg. The high inclinations of NTs are indicative of capture instead of in situ formation. Here we study a model in which NTs were captured by Neptune during planetary migration when secondary resonances associated with the mean-motion commensurabilities between Uranus and Neptune swept over Neptune's Lagrangian points. This process, known as chaotic capture, is similar to that previously proposed to explain the origin of Jupiter's Trojans. We show that chaotic capture of planetesimals from an ∼35 Earth-mass planetesimal disk can produce a population of NTs that is at least comparable in number to that inferred from current observations. The large orbital inclinations of NTs are a natural outcome of chaotic capture. To obtain the ∼4:1 ratio between high- and low-inclination populations suggested by observations, planetary migration into a dynamically excited planetesimal disk may be required. The required stirring could have been induced by Pluto-sized and larger objects that have formed in the disk.

  4. Safety implications of reactivity variations in fast thorium ADSRs

    International Nuclear Information System (INIS)

    Highlights: ► A lumped fast reactor model is used to simulate reactivity and power variations in a fast thorium ADSR. ► Neutron flux changes produce reactivity changes due to shifts in the 233Pa and 233U populations. ► On reactor start-up, the reactivity will fall in the early part of the burn-up. ► On reactor shutdown the reactivity will increase. ► A thorium fuelled ADSR operating at keff ⩾ 0.990 is at risk from an accelerator-trip-induced post-shutdown criticality excursion. - Abstract: Nuclear power generation offers a reliable, low-impact and large-scale alternative to fossil fuels. However, concerns exist over the safety and sustainability of this method of power production, and it remains unpopular with some governments and pressure groups throughout the world. Fast thorium fuelled accelerator-driven sub-critical reactors (ADSRs) offer a possible route to providing further re-assurance regarding these concerns on account of their properties of enhanced safety through sub-critical operation combined with reduced actinide waste production from the thorium fuel source. The appropriate sub-critical margin at which these reactors should operate is the subject of continued debate. Commercial interests favour a small sub-critical margin in order to minimise the size of the accelerator needed for a given power output, whilst enhanced safety would be better satisfied through larger sub-critical margins to further minimise the possibility of a criticality excursion. Against this background, this paper examines some of the issues affecting reactor safety inherent within thorium fuel sources resulting from the essential 23290Th→23390Th→23391Pa→23392U breeding chain. Differences in the decay half-lives and fission and capture cross-sections of 233Pa and 233U can result in significant changes in the reactivity of the fuel following changes in the reactor power. Reactor operation is represented using a homogeneous lumped fast reactor model that can

  5. Characterization of a 10B-doped liquid scintillator as a capture-gated neutron spectrometer

    Science.gov (United States)

    Hunt, S.; Iliadis, C.; Longland, R.

    2016-03-01

    We use a 250 MHz digitizer to characterize the pulse shape discrimination of a BC-523A 10B-doped liquid scintillator with capture-gating capabilities. Our results are compared to recent work claiming pulse shape discrimination between fast and thermal neutron signals. The capture event is identified, and we explain the origin of signals that are often misinterpreted. We use the time-of-flight method to measure the detector energy resolution for fast incident monoenergetic neutrons and the intrinsic neutron detection efficiency. Monte Carlo simulations are performed and we find agreement between measured and simulated results. These steps are important for understanding 10B-doped capture-gated spectroscopy in mixed radiation environments, as efficiencies using capture-gating are rarely reported in the literature.

  6. Dynamic Operation and Simulation of Post-Combustion CO2 Capture

    DEFF Research Database (Denmark)

    Gaspar, Jozsef; Gladis, Arne; Jørgensen, John Bagterp;

    2016-01-01

    Thermal power need to operate, on a daily basis, with frequent and fast load changes to balance the large variations of intermittent energy sources, such as wind and solar energy. To make the integration of carbon capture to power plants economically and technically feasible, the carbon capture...... process has to be able to follow these fast and large load changes without decreasing the overall performance of the carbon capture plant. Therefore, dynamic models for simulation, optimization and control system design are essential. In this work, we compare the transient behavior of the model against...... dynamic pilot data for CO2 absorption and desorption for step-changes in the flue gas flow rate. In addition we investigate the dynamic behavior of a full-scale post-combustion capture plant using monoethanolamine (MEA) and piperazine (PZ). This analysis demonstrates the good agreement between the...

  7. Fast food (image)

    Science.gov (United States)

    Fast foods are quick, reasonably priced, and readily available alternatives to home cooking. While convenient and economical for a busy lifestyle, fast foods are typically high in calories, fat, saturated fat, ...

  8. Fast food tips (image)

    Science.gov (United States)

    ... challenge to eat healthy when going to a fast food place. In general, avoiding items that are deep ... challenge to eat healthy when going to a fast food place. In general, avoiding items that are deep ...

  9. Proton capture by magnetic monopoles

    International Nuclear Information System (INIS)

    In the Kazama-Yang approximation, the lowest monopole-proton bound states have binding energies of 938 MeV, 263 keV, 105 eV, and 0.04 eV. The cross section for radiative capture to these states is for velocities β = 10-5 - 10-3 found to be of the order of 10-28 - 10-26 cm2. For the state that has a binding energy of 263 keV, the capture length in water is 171 x (β/10-4)sup(0.48) m. Observation of photons from the capture process would indicate the presence of monopoles. (orig.)

  10. Laser-plasma interactions for fast ignition

    OpenAIRE

    Kemp, A. J.; Fiuza, F.; Debayle, A.; Johzaki, T.; Mori, W. B.; P.K. Patel; Sentoku, Y.; Silva, L. O.

    2014-01-01

    In the electron-driven fast-ignition approach to inertial confinement fusion, petawatt laser pulses are required to generate MeV electrons that deposit several tens of kilojoules in the compressed core of an imploded DT shell. We review recent progress in the understanding of intense laser plasma interactions (LPI) relevant to fast ignition. Increases in computational and modeling capabilities, as well as algorithmic developments have led to enhancement in our ability to perform multi-dimensi...

  11. Fasting and Urinary Stones

    OpenAIRE

    Ali Shamsa

    2013-01-01

    Introduction: Fasting is considered as one of the most important practices of Islam, and according to Prophet Mohammad, fasting is obligatory upon Muslims. The aim of this study is to evaluate the effects of fasting on urinary stones. Materials and Methods: Very few studies have been carried out on urinary stones and the effect of Ramadan fasting. The sources of the present study are Medline and articles presented by local and Muslim researchers. Meanwhile, since we are acquainted ...

  12. Ramadan, fasting and pregnancy

    DEFF Research Database (Denmark)

    Ahmed, Urfan Zahoor; Lykke, Jacob Alexander

    2014-01-01

    In Islam, the month of Ramadan is a period of fasting lasting 29 or 30 days. Epidemiological studies among Muslims in Denmark have not been conducted, but studies show, that fasting among pregnant Muslim women is common. Fasting does not increase the risk of growth restriction or preterm delivery...... month of Ramadan to a later period....

  13. Ramadan, faste og graviditet

    DEFF Research Database (Denmark)

    Ahmed, Urfan Zahoor; Lykke, Jacob Alexander

    2014-01-01

    In Islam, the month of Ramadan is a period of fasting lasting 29 or 30 days. Epidemiological studies among Muslims in Denmark have not been conducted, but studies show, that fasting among pregnant Muslim women is common. Fasting does not increase the risk of growth restriction or preterm delivery...... month of Ramadan to a later period....

  14. Evaluation of commercial chromatographic adsorbents for the direct capture of polyclonal rabbit antibodies from clarified antiserum

    DEFF Research Database (Denmark)

    Bak, Hanne; Thomas, O.R.T.

    2007-01-01

    We have carried out a rigorous evaluation of eight commercially available packed bed chromatography adsorbents for direct capture and purification of immumoglobulins from clarified rabbit antiserum. Three of these materials featured rProtein A (rProtein A Sepharose Fast Flow, Mabselect, Prosep rProtein...... evaluated on the basis of dynamic binding capacity, recovery, and purity) were obtained, which allowed clear recommendations concerning the choice of adsorbents best suited for antibody capture from rabbit antisera, to be made....

  15. Integral test of JENDL-3.3 for fast reactors

    International Nuclear Information System (INIS)

    An integral test of JENDL-3.3 was performed for fast reactors. Various types of fast reactors were analyzed. Calculation values of the nuclear characteristics were greatly especially affected by the revisions of the cross sections of U-235 capture and elastic scattering reactions. The C/E values were improved for ZPPR cross where plutonium is mainly fueled, but not for BFS cores where uranium is mainly fueled. (author)

  16. Active chemisorption sites in functionalized ionic liquids for carbon capture.

    Science.gov (United States)

    Cui, Guokai; Wang, Jianji; Zhang, Suojiang

    2016-07-25

    Development of novel technologies for the efficient and reversible capture of CO2 is highly desired. In the last decade, CO2 capture using ionic liquids has attracted intensive attention from both academia and industry, and has been recognized as a very promising technology. Recently, a new approach has been developed for highly efficient capture of CO2 by site-containing ionic liquids through chemical interaction. This perspective review focuses on the recent advances in the chemical absorption of CO2 using site-containing ionic liquids, such as amino-based ionic liquids, azolate ionic liquids, phenolate ionic liquids, dual-functionalized ionic liquids, pyridine-containing ionic liquids and so on. Other site-containing liquid absorbents such as amine-based solutions, switchable solvents, and functionalized ionic liquid-amine blends are also investigated. Strategies have been discussed for how to activate the existent reactive sites and develop novel reactive sites by physical and chemical methods to enhance CO2 absorption capacity and reduce absorption enthalpy. The carbon capture mechanisms of these site-containing liquid absorbents are also presented. Particular attention has been paid to the latest progress in CO2 capture in multiple-site interactions by amino-free anion-functionalized ionic liquids. In the last section, future directions and prospects for carbon capture by site-containing ionic liquids are outlined. PMID:27243042

  17. [Ramadan, fasting and pregnancy].

    Science.gov (United States)

    Ahmed, Urfan Zahoor; Lykke, Jacob Alexander

    2014-07-14

    In Islam, the month of Ramadan is a period of fasting lasting 29 or 30 days. Epidemiological studies among Muslims in Denmark have not been conducted, but studies show, that fasting among pregnant Muslim women is common. Fasting does not increase the risk of growth restriction or preterm delivery, but there are reports of decreased foetal movements. Furthermore, the fasting may have long-term health consequences for the offspring, especially when they reach their middle age. According to Islam and the interpretation, pregnant and breast-feeding women are allowed to postpone the fasting of the month of Ramadan to a later period. PMID:25292203

  18. Fast R-CNN

    OpenAIRE

    Girshick, Ross

    2015-01-01

    This paper proposes a Fast Region-based Convolutional Network method (Fast R-CNN) for object detection. Fast R-CNN builds on previous work to efficiently classify object proposals using deep convolutional networks. Compared to previous work, Fast R-CNN employs several innovations to improve training and testing speed while also increasing detection accuracy. Fast R-CNN trains the very deep VGG16 network 9x faster than R-CNN, is 213x faster at test-time, and achieves a higher mAP on PASCAL VOC...

  19. Recombination methods for boron neutron capture therapy dosimetry

    International Nuclear Information System (INIS)

    The radiation effects of boron neutron capture therapy (BNCT) are associated with four-dose-compartment radiation field - boron dose (from 10B(n,α)7Li) reaction), proton dose from 14N(n,p)14C reaction, neutron dose (mainly fast and epithermal neutrons) and gamma-ray dose (external and from capture reaction 1H(n,γ)2D). Because of this the relation between the absorbed dose and the biological effects is very complex and all the above mentioned absorbed dose components should be determined. From this point of view, the recombination chambers can be very useful instruments for characterization of the BNCT beams. They can be used for determination of gamma and high-LET dose components for the characterization of radiation quality of mixed radiation fields by recombination microdosimetric method (RMM). In present work, a graphite high-pressure recombination chamber filled with nitrogen, 10BF3 and tissue equivalent gas was used for studies on application of RMM for BNCT dosimetry. The use of these gases or their mixtures opens a possibility to design a recombination chamber for determination of the dose fractions due to gamma radiation, fast neutrons, neutron capture on nitrogen and high LET particles from (n,10B) reaction in simulated tissue with different content of 10B. (author)

  20. The Economics of Carbon Capture

    OpenAIRE

    Islegen Ozge; Reichelstein Stefan J

    2009-01-01

    As carbon capture technologies are likely to allow power plants to reduce emissions by up to 90 percent, Ozge Islegen and Stefan Reichelstein of Stanford Business School feel that plants will choose to implement such technologies to avoid paying even modest emissions permit prices.

  1. Prey capture by harbor porpoises

    DEFF Research Database (Denmark)

    Miller, Lee; Verfuss, Ursula

    2009-01-01

    source levels of clicks decrease by about half (6dB) for each halving of distance to the prey. The sequence ends in a terminal, high repetition rate buzz (~500 clicks/s) just before capturing the prey (a video will be shown). The temporal sequence differs from that of beaked whales, but is like that of...

  2. Prey capture by harbor porpoises

    DEFF Research Database (Denmark)

    Miller, Lee

    2008-01-01

    ) that progressively decrease when closing on an object.  After detecting the prey, the click interval stabilizes and then becomes progressively shorter while approaching the prey.  The sequence ends in a terminal, high repetition rate buzz (~500 clicks/s) just before capturing the prey (a video will be...

  3. Neutron-capture nucleosynthesis in the first stars

    International Nuclear Information System (INIS)

    Recent studies suggest that metal-poor stars enhanced in carbon but containing low levels of neutron-capture elements may have been among the first to incorporate the nucleosynthesis products of the first generation of stars. We have observed 16 stars with enhanced carbon or nitrogen using the MIKE Spectrograph on the Magellan Telescopes at Las Campanas Observatory and the Tull Spectrograph on the Smith Telescope at McDonald Observatory. We present radial velocities, stellar parameters, and detailed abundance patterns for these stars. Strontium, yttrium, zirconium, barium, europium, ytterbium, and other heavy elements are detected. In four stars, these heavy elements appear to have originated in some form of r-process nucleosynthesis. In one star, a partial s-process origin is possible. The origin of the heavy elements in the rest of the sample cannot be determined unambiguously. The presence of elements heavier than the iron group offers further evidence that zero-metallicity rapidly rotating massive stars and pair instability supernovae did not contribute substantial amounts of neutron-capture elements to the regions where the stars in our sample formed. If the carbon- or nitrogen-enhanced metal-poor stars with low levels of neutron-capture elements were enriched by products of zero-metallicity supernovae only, then the presence of these heavy elements indicates that at least one form of neutron-capture reaction operated in some of the first stars.

  4. Earth--Mars Transfers with Ballistic Capture

    OpenAIRE

    Topputo, Francesco; Belbruno, Edward

    2014-01-01

    We construct a new type of transfer from the Earth to Mars, which ends in ballistic capture. This results in a substantial savings in capture $\\Delta v$ from that of a classical Hohmann transfer under certain conditions. This is accomplished by first becoming captured at Mars, very distant from the planet, and then from there, following a ballistic capture transfer to a desired altitude within a ballistic capture set. This is achieved by manipulating the stable sets, or sets of initial condit...

  5. High Spatial Resolution Fast-Neutron Imaging Detectors for Pulsed Fast-Neutron Transmission Spectroscopy

    OpenAIRE

    Mor, I.; Vartsky, D.; Bar, D.; Feldman, G.; Goldberg, M B; Katz, D.; Sayag, E.; Shmueli, I.; Cohen, Y.; Tal, A; Vagish, Z.; Bromberger, B.; Dangendorf, V.; Mugai, D.; Tittelmeier, K.

    2009-01-01

    Two generations of a novel detector for high-resolution transmission imaging and spectrometry of fast-neutrons are presented. These devices are based on a hydrogenous fiber scintillator screen and single- or multiple-gated intensified camera systems (ICCD). This detector is designed for energy-selective neutron radiography with nanosecond-pulsed broad-energy (1 - 10 MeV) neutron beams. Utilizing the Time-of-Flight (TOF) method, such a detector is capable of simultaneously capturing several im...

  6. Molecular profiling of activated neurons by phosphorylated ribosome capture.

    Science.gov (United States)

    Knight, Zachary A; Tan, Keith; Birsoy, Kivanc; Schmidt, Sarah; Garrison, Jennifer L; Wysocki, Robert W; Emiliano, Ana; Ekstrand, Mats I; Friedman, Jeffrey M

    2012-11-21

    The mammalian brain is composed of thousands of interacting neural cell types. Systematic approaches to establish the molecular identity of functional populations of neurons would advance our understanding of neural mechanisms controlling behavior. Here, we show that ribosomal protein S6, a structural component of the ribosome, becomes phosphorylated in neurons activated by a wide range of stimuli. We show that these phosphorylated ribosomes can be captured from mouse brain homogenates, thereby enriching directly for the mRNAs expressed in discrete subpopulations of activated cells. We use this approach to identify neurons in the hypothalamus regulated by changes in salt balance or food availability. We show that galanin neurons are activated by fasting and that prodynorphin neurons restrain food intake during scheduled feeding. These studies identify elements of the neural circuit that controls food intake and illustrate how the activity-dependent capture of cell-type-specific transcripts can elucidate the functional organization of a complex tissue. PMID:23178128

  7. Accelerator based neutron source for neutron capture therapy

    International Nuclear Information System (INIS)

    Full text: The Budker Institute of Nuclear Physics (Novosibirsk) and the Institute of Physics and Power Engineering (Obninsk) have proposed an accelerator based neutron source for neutron capture and fast neutron therapy for hospital. Innovative approach is based upon vacuum insulation tandem accelerator (VITA) and near threshold 7Li(p,n)7Be neutron generation. Pilot accelerator based neutron source for neutron capture therapy is under construction now at the Budker Institute of Nuclear Physics, Novosibirsk, Russia. In the present report, the pilot facility design is presented and discussed. Design features of facility components are discussed. Results of experiments and simulations are presented. Complete experimental tests are planned by the end of the year 2005

  8. Development of motion capture system using alternating magnetic field

    Science.gov (United States)

    Kumagai, Masaaki; Akamatsu, Kazuyoshi

    2005-12-01

    Motion capture systems are widely used for virtual reality, motion acquisition for medical researches, for humanoid robots, for video games, etc. Several types of them have been developed and used for applications considering their advantages and restrictions. Another type of motion capture system that uses alternating magnetic field is proposed in this paper. The system uses a field exciting coil that covers measuring area and a pickup coil attached to target. First, six alternating fields are generated simultaneously in measuring area, and signals are induced on pickup coils according to attitude and position of it. These signals are processed to extract amplitude of exciting components, and state of the pickup coil is calculated from those components. It can detect attitude and displacement of target with high resolution and fast response speed. The principles of detection and brief experimental results are described.

  9. Muon capture on 3H

    CERN Document Server

    Golak, J; Witala, H; Topolnicki, K; Kamada, H; Nogga, A; Marcucci, L E

    2016-01-01

    The muon capture on 3H leading to muonic neutrino and three neutrons in the final state is studied under full inclusion of final state interactions. Predictions for the three-body break-up of 3H are calculated with the AV18 potential, augmented by the Urbana IX three-nucleon force. Our results are based on the single nucleon weak current operator comprising the dominant relativistic corrections. This work is a natural extension of our investigations of the muon capture on 3He leading to 3H or n+d or n+n+p and muonic neutrino in the final state, presented in Phys. Rev. C90, 024001 (2014).

  10. Experimental studies of electron capture

    International Nuclear Information System (INIS)

    This thesis discusses the main results of recent experimental studies of electron capture in asymmetric collisions. Most of the results have been published, but the thesis also contains yet unpublished data, or data presented only in unrefereed conference proceedings. The thesis aims at giving a coherent discussion of the understanding of the experimental results, based first on simple qualitative considerations and subsequently on quantitative comparisons with the best theoretical calculations currently available. (Auth.)

  11. Laser Capture Microdissection in Dentistry

    OpenAIRE

    Uraiwan Chokechanachaisakul; Tomoatsu Kaneko; Takashi Okiji; Reika Kaneko; Hideaki Suda; Jacques E. Nör

    2010-01-01

    Laser capture microdissection (LCM) allows for the microscopic procurement of specific cell types from tissue sections that can then be used for gene expression analysis. According to the recent development of the LCM technologies and methodologies, the LCM has been used in various kinds of tissue specimens in dental research. For example, the real-time polymerase-chain reaction (PCR) can be performed from the formaldehyde-fixed, paraffin-embedded, and immunostained sections. Thus, the advanc...

  12. Fast global sequence alignment technique

    KAUST Repository

    Bonny, Mohamed Talal

    2011-11-01

    Bioinformatics database is growing exponentially in size. Processing these large amount of data may take hours of time even if super computers are used. One of the most important processing tool in Bioinformatics is sequence alignment. We introduce fast alignment algorithm, called \\'Alignment By Scanning\\' (ABS), to provide an approximate alignment of two DNA sequences. We compare our algorithm with the wellknown sequence alignment algorithms, the \\'GAP\\' (which is heuristic) and the \\'Needleman-Wunsch\\' (which is optimal). The proposed algorithm achieves up to 51% enhancement in alignment score when it is compared with the GAP Algorithm. The evaluations are conducted using different lengths of DNA sequences. © 2011 IEEE.

  13. Segments graph-based approach for smartphone document capture

    Science.gov (United States)

    Zhukovsky, Alexander E.; Arlazarov, Vladimir V.; Postnikov, Vasiliy V.; Krivtsov, Valeriy E.

    2015-12-01

    Document capture with a smartphone camera is already here to stay. Interactive applications for document capture and its enhancement have filled mobile application stores. However, discounting the predictions and judging only from the experience of using such applications, they are not yet ready to compete with stationary scanners when high quality and reliability is required. This paper is devoted to analysis of the problem of document detection in the image and evaluation of the quality of existing mobile applications. Based on this analysis we present a new reliable algorithm for document capture, based on the boundary segments detection and constructing a segments graph to fit rectangular projective model. The algorithm achieves about 95% quality of document detection and outperforms all of the reviewed algorithms, implemented in mobile applications.

  14. Fast blood flow visualization of high-resolution laser speckle imaging data using graphics processing unit.

    Science.gov (United States)

    Liu, Shusen; Li, Pengcheng; Luo, Qingming

    2008-09-15

    Laser speckle contrast analysis (LASCA) is a non-invasive, full-field optical technique that produces two-dimensional map of blood flow in biological tissue by analyzing speckle images captured by CCD camera. Due to the heavy computation required for speckle contrast analysis, video frame rate visualization of blood flow which is essentially important for medical usage is hardly achieved for the high-resolution image data by using the CPU (Central Processing Unit) of an ordinary PC (Personal Computer). In this paper, we introduced GPU (Graphics Processing Unit) into our data processing framework of laser speckle contrast imaging to achieve fast and high-resolution blood flow visualization on PCs by exploiting the high floating-point processing power of commodity graphics hardware. By using GPU, a 12-60 fold performance enhancement is obtained in comparison to the optimized CPU implementations. PMID:18794967

  15. Double-electron capture in relativistic U{sup 92+} collisions at the ESR gas-jet target

    Energy Technology Data Exchange (ETDEWEB)

    Bednarz, G. E-mail: d.sierpowski@gsi.deufsierpo@if.uj.edu.pl; Sierpowski, D.; Stoehlker, Th.; Warczak, A.; Beyer, H.; Bosch, F.; Braeuning-Demian, A.; Braeuning, H.; Cai, X.; Gumberidze, A.; Hagmann, S.; Kozhuharov, C.; Liesen, D.; Ma, X.; Mokler, P.H.; Muthig, A.; Stachura, Z.; Toleikis, S

    2003-05-01

    Total cross-sections for radiative single- and double-electron capture are measured in collisions of fast highly charged ions with light target atoms. Cross-sections for non-correlated double capture are in accordance with theoretical predictions. No significant line structure at twice the single K-radiative electron capture (K-REC) photon energy was observed. Angular distributions single K-REC photons associated with single- and double-charge exchange exhibit the same pattern. The corresponding REC lines are almost by a factor of two broader for double-charge exchange than in the single capture case.

  16. Fast food (image)

    Science.gov (United States)

    ... quick, reasonably priced, and readily available alternatives to home cooking. While convenient and economical for a busy lifestyle, fast foods are typically high in calories, fat, saturated fat, ...

  17. Fast wave current drive

    Energy Technology Data Exchange (ETDEWEB)

    Goree, J.; Ono, M.; Colestock, P.; Horton, R.; McNeill, D.; Park, H.

    1985-07-01

    Fast wave current drive is demonstrated in the Princeton ACT-I toroidal device. The fast Alfven wave, in the range of high ion-cyclotron harmonics, produced 40 A of current from 1 kW of rf power coupled into the plasma by fast wave loop antenna. This wave excites a steady current by damping on the energetic tail of the electron distribution function in the same way as lower-hybrid current drive, except that fast wave current drive is appropriate for higher plasma densities.

  18. A graphene oxide/amidoxime hydrogel for enhanced uranium capture

    OpenAIRE

    Feihong Wang; Hongpeng Li; Qi Liu; Zhanshuang Li; Rumin Li; Hongsen Zhang; Lianhe Liu; Emelchenko, G. A.; Jun Wang

    2016-01-01

    The efficient development of selective materials for the recovery of uranium from nuclear waste and seawater is necessary for their potential application in nuclear fuel and the mitigation of nuclear pollution. In this work, a graphene oxide/amidoxime hydrogel (AGH) exhibits a promising adsorption performance for uranium from various aqueous solutions, including simulated seawater. We show high adsorption capacities (Qm = 398.4 mg g−1) and high % removals at ppm or ppb levels in aqueous solut...

  19. Neutron Capture Reactions for Stockpile Stewardship and Basic Science

    Energy Technology Data Exchange (ETDEWEB)

    Parker, W; Agvaanluvsan, U; Becker, J; Wilk, P; Wu, C; Bredeweg, T; Couture, A; Haight, R; Jandel, M; O' Donnell, J; Reifarth, R; Rundberg, R; Ullmann, J; Vieira, D; Wouters, J; Sheets, S; Mitchell, G; Becvar, F; Krticka, M

    2007-08-04

    The capture process is a nuclear reaction in which a target atom captures an incident projectile, e.g. a neutron. The excited-state compound nucleus de-excites by emitting photons. This process creates an atom that has one more neutron than the target atom, so it is a different isotope of the same element. With low energy (slow) neutron projectiles, capture is the dominant reaction, other than elastic scattering. However, with very heavy nuclei, fission competes with capture as a method of de-excitation of the compound nucleus. With higher energy (faster) incident neutrons, additional reactions are also possible, such as emission of protons or emission of multiple neutrons. The probability of a particular reaction occurring (such as capture) is referred to as the cross section for that reaction. Cross sections are very dependent on the incoming neutron's energy. Capture reactions can be studied either using monoenergetic neutron sources or 'white' neutron sources. A 'white' neutron source has a wide range of neutron energies in one neutron beam. The advantage to the white neutron source is that it allows the study of cross sections as they depend on neutron energies. The Los Alamos Neutron Science Center, located at Los Alamos National Laboratory, provides an intense white neutron source. Neutrons there are created by a high-energy proton beam from a linear accelerator striking a heavy metal (tungsten) target. The neutrons range in energy from subthermal up to very fast - over 100 MeV in energy. Low-energy neutron reaction cross sections fluctuate dramatically from one target to another, and they are very difficult to predict by theoretical modeling. The cross sections for particular capture reactions are important for defense sciences, advanced reactor concepts, transmutation of radioactive wastes and nuclear astrophysics. We now have a strong collaboration between Lawrence Livermore National Laboratory, Los Alamos National Laboratory

  20. [Medical aspects of fasting].

    Science.gov (United States)

    Gavrankapetanović, F

    1997-01-01

    Fasting (arabic-savm) was proclaimed through islam, and thus it is an obligation for Holly Prophet Muhammad s.a.v.s.-Peace be to Him-in the second year after Hijra (in 624 after Milad-born of Isa a.s.). There is a month of fasting-Ramadan-each lunar (hijra) year. So, it was 1415th fasting this year. Former Prophets have brought obligative messages on fasting to their people; so there are also certain forms of fasting with other religions i.e. with Catholics, Jews, Orthodox. These kinds of fasting above differ from muslim fasting, but they also appear obligative. All revelations have brought fasting as obligative. From medical point of view, fasting has two basical components: psychical and physical. Psychical sphere correlate closely with its fundamental ideological message. Allah dz.s. says in Quran: "... Fasting is obligative for you, as it was obligative to your precedents, as to avoid sins; during very few days (II, II, 183 & 184)." Will strength, control of passions, effort and self-discipline makes a pure faithfull person, who purify its mind and body through fasting. Thinking about The Creator is more intensive, character is more solid; and spirit and will get stronger. We will mention the hadith saying: "Essaihune humus saimun!" That means: "Travellers at the Earth are fasters (of my ummet)." The commentary of this hadith, in the Collection of 1001 hadiths (Bin bir hadis), number 485, says: "There are no travelling dervishs or monks in islam; thus there is no such a kind of relligousity in islam. In stead, it is changed by fasting and constant attending of mosque. That was proclaimed as obligation, although there were few cases of travelling in the name of relligousity, like travelling dervishs and sheichs." In this paper, the author discusses medical aspects of fasting and its positive characteristics in the respect of healthy life style and prevention of many sicks. The author mentions positive influence of fasting to certain system and organs of human

  1. Financing Capture Ready Coal-Fired Power Plants In China By Issuing Capture Options

    OpenAIRE

    Liang, Xi; Reiner, David; Gibbons, Jon; Jia LI

    2007-01-01

    ?Capture Ready? is a design concept enabling fossil fuel plants to be retrofitted more economically with carbon dioxide capture and storage (CCS) technologies, however financing the cost of capture ready can be problematic, especially in the developing world. We propose that fossil fuel plants issue tradable Capture Options to acquire financing. The Capture Option concept could move CCS forward politically in countries such as China, speed up CCS technology development, help Capture Ready inv...

  2. A bottleneck model of set-specific capture.

    Directory of Open Access Journals (Sweden)

    Katherine Sledge Moore

    Full Text Available Set-specific contingent attentional capture is a particularly strong form of capture that occurs when multiple attentional sets guide visual search (e.g., "search for green letters" and "search for orange letters". In this type of capture, a potential target that matches one attentional set (e.g. a green stimulus impairs the ability to identify a temporally proximal target that matches another attentional set (e.g. an orange stimulus. In the present study, we investigated whether set-specific capture stems from a bottleneck in working memory or from a depletion of limited resources that are distributed across multiple attentional sets. In each trial, participants searched a rapid serial visual presentation (RSVP stream for up to three target letters (T1-T3 that could appear in any of three target colors (orange, green, or lavender. The most revealing findings came from trials in which T1 and T2 matched different attentional sets and were both identified. In these trials, T3 accuracy was lower when it did not match T1's set than when it did match, but only when participants failed to identify T2. These findings support a bottleneck model of set-specific capture in which a limited-capacity mechanism in working memory enhances only one attentional set at a time, rather than a resource model in which processing capacity is simultaneously distributed across multiple attentional sets.

  3. The role of magnocellular signals in oculomotor attentional capture.

    Science.gov (United States)

    Leonard, Carly J; Luck, Steven J

    2011-01-01

    While it is known that salient distractors often capture covert and overt attention, it is unclear whether salience signals that stem from magnocellular visual input have a more dominant role in oculomotor capture than those that result from parvocellular input. Because of the direct anatomical connections between the magnocellular pathway and the superior colliculus, salience signals generated from the magnocellular pathway may produce greater oculomotor capture than those from the parvocellular pathway, which could be potentially harder to overcome with "top-down," goal-directed guidance. Although previous research has addressed this with regard to magnocellular transients, in the current research, we investigated whether a static singleton distractor defined along a dimension visible to the magnocellular pathway would also produce enhanced oculomotor capture. In two experiments, we addressed this possibility by comparing a parvo-biased singleton condition, in which the distractor was defined by isoluminant chromatic color contrast, with a magno + parvo singleton condition, in which the distractor also differed in luminance from the surrounding objects. In both experiments, magno + parvo singletons elicited faster eye movements than parvo-only singletons, presumably reflecting faster information transmission in the magnocellular pathway, but magno + parvo singletons were not significantly more likely to produce oculomotor capture. Thus, although magnocellular salience signals are available more rapidly, they have no sizable advantage over parvocellular salience signals in controlling oculomotor orienting when all stimuli have a common onset. PMID:22076486

  4. Asteroid Redirect Robotic Mission: Robotic Boulder Capture Option Overview

    Science.gov (United States)

    Mazanek, Daniel D.; Merrill, Raymond G.; Belbin, Scott P.; Reeves, David M.; Earle, Kevin D.; Naasz, Bo J.; Abell, Paul A.

    2014-01-01

    The National Aeronautics and Space Administration (NASA) is currently studying an option for the Asteroid Redirect Robotic Mission (ARRM) that would capture a multi-ton boulder (typically 2-4 meters in size) from the surface of a large (is approximately 100+ meter) Near-Earth Asteroid (NEA) and return it to cislunar space for subsequent human and robotic exploration. This alternative mission approach, designated the Robotic Boulder Capture Option (Option B), has been investigated to determine the mission feasibility and identify potential differences from the initial ARRM concept of capturing an entire small NEA (4-10 meters in size), which has been designated the Small Asteroid Capture Option (Option A). Compared to the initial ARRM concept, Option B allows for centimeter-level characterization over an entire large NEA, the certainty of target NEA composition type, the ability to select the boulder that is captured, numerous opportunities for mission enhancements to support science objectives, additional experience operating at a low-gravity planetary body including extended surface contact, and the ability to demonstrate future planetary defense strategies on a hazardous-size NEA. Option B can leverage precursor missions and existing Agency capabilities to help ensure mission success by targeting wellcharacterized asteroids and can accommodate uncertain programmatic schedules by tailoring the return mass.

  5. High-Performance Sorbents for Carbon Dioxide Capture from Air

    Energy Technology Data Exchange (ETDEWEB)

    Sholl, David; Jones, Christopher

    2013-03-13

    This project has focused on capture of CO{sub 2} from ambient air (“air capture”). If this process is technically and economically feasible, it could potentially contribute to net reduction of CO{sub 2} emissions in ways that are complementary to better developed techniques for CO{sub 2} from concentrated point sources. We focused on cyclic adsorption processes for CO{sub 2} capture from air in which the entire cycle is performed at moderate temperatures. The project involved both experimental studies of sorbent materials and process level modeling of cyclic air capture processes. In our experimental work, a series of amine-functionalized silica adsorbents were prepared and characterized to determine the impact of molecular architecture on CO{sub 2} capture. Some key findings were: • Amine functionalized silicas can be prepared with high enough CO{sub 2} capacities under ambient conditions to merit consideration for use in air capture processes. • Primary amines are better candidates for CO{sub 2} capture than secondary or tertiary amines, both in terms of amine efficiency for CO{sub 2} adsorption and enhanced water affinity. • Mechanistic understanding of degradation of these materials can enable control of molecular architecture to significantly improve material stability. Our process modeling work provided the first publically available cost and energy estimates for cyclic adsorption processes for air capture of CO{sub 2}. Some key findings were: • Cycles based on diurnal ambient heating and cooling cannot yield useful purities or amounts of captured CO{sub 2}. • Cycles based on steam desorption at 110 oC can yield CO{sub 2} purities of ~88%. • The energy requirements for cycles using steam desorption are dominated by needs for thermal input, which results in lower costs than energy input in the form of electricity. Cyclic processes with operational costs of less than $100 tCO{sub 2}-net were described, and these results point to process and

  6. Final Report on Actinide Glass Scintillators for Fast Neutron Detection

    Energy Technology Data Exchange (ETDEWEB)

    Bliss, Mary; Stave, Jean A.

    2012-10-01

    This is the final report of an experimental investigation of actinide glass scintillators for fast-neutron detection. It covers work performed during FY2012. This supplements a previous report, PNNL-20854 “Initial Characterization of Thorium-loaded Glasses for Fast Neutron Detection” (October 2011). The work in FY2012 was done with funding remaining from FY2011. As noted in PNNL-20854, the glasses tested prior to July 2011 were erroneously identified as scintillators. The decision was then made to start from “scratch” with a literature survey and some test melts with a non-radioactive glass composition that could later be fabricated with select actinides, most likely thorium. The normal stand-in for thorium in radioactive waste glasses is cerium in the same oxidation state. Since cerium in the 3+ state is used as the light emitter in many scintillating glasses, the next most common substitute was used: hafnium. Three hafnium glasses were melted. Two melts were colored amber and a third was clear. It barely scintillated when exposed to alpha particles. The uses and applications for a scintillating fast neutron detector are important enough that the search for such a material should not be totally abandoned. This current effort focused on actinides that have very high neutron capture energy releases but low neutron capture cross sections. This results in very long counting times and poor signal to noise when working with sealed sources. These materials are best for high flux applications and access to neutron generators or reactors would enable better test scenarios. The total energy of the neutron capture reaction is not the only factor to focus on in isotope selection. Many neutron capture reactions result in energetic gamma rays that require large volumes or high densities to detect. If the scintillator is to separate neutrons from gamma rays, the capture reactions should produce heavy particles and few gamma rays. This would improve the detection of a

  7. Advanced Multiphysics Modeling of Fast Reactor Fuel Behavior

    International Nuclear Information System (INIS)

    Evaluation of fast reactor fuel thermo-mechanical performance using fuel performance codes is a key aspect of advanced fast reactors designs. Those fuel performance codes capture the multiphysics nature of fuel behavior during irradiation where different, mostly interdependent, phenomena are taking place. Existing fuel performance codes do not fully capture those interdependencies and present the different phenomena through de-coupled models. Recent developments in multiphysics simulation capabilities and availability of advanced computing platforms led to advancements in simulation of nuclear fuel behavior. This paper presents current experiences in applying different multiphysics simulation platforms to evaluation of fast reactors metallic fuel behavior. Full 3D finite element simulation platforms that include capabilities to fully couple key fuel behavior models are discussed. Issues associated with coupling metallic fuels phenomena, such as fission gas models and constituent distribution models, with thermo-mechanical finite element platforms, as well as different coupling schemes are also discussed. (author)

  8. Realistic costs of carbon capture

    Energy Technology Data Exchange (ETDEWEB)

    Al Juaied, Mohammed (Harvard Univ., Cambridge, MA (US). Belfer Center for Science and International Affiaris); Whitmore, Adam (Hydrogen Energy International Ltd., Weybridge (GB))

    2009-07-01

    There is a growing interest in carbon capture and storage (CCS) as a means of reducing carbon dioxide (CO2) emissions. However there are substantial uncertainties about the costs of CCS. Costs for pre-combustion capture with compression (i.e. excluding costs of transport and storage and any revenue from EOR associated with storage) are examined in this discussion paper for First-of-a-Kind (FOAK) plant and for more mature technologies, or Nth-of-a-Kind plant (NOAK). For FOAK plant using solid fuels the levelised cost of electricity on a 2008 basis is approximately 10 cents/kWh higher with capture than for conventional plants (with a range of 8-12 cents/kWh). Costs of abatement are found typically to be approximately US$150/tCO2 avoided (with a range of US$120-180/tCO2 avoided). For NOAK plants the additional cost of electricity with capture is approximately 2-5 cents/kWh, with costs of the range of US$35-70/tCO2 avoided. Costs of abatement with carbon capture for other fuels and technologies are also estimated for NOAK plants. The costs of abatement are calculated with reference to conventional SCPC plant for both emissions and costs of electricity. Estimates for both FOAK and NOAK are mainly based on cost data from 2008, which was at the end of a period of sustained escalation in the costs of power generation plant and other large capital projects. There are now indications of costs falling from these levels. This may reduce the costs of abatement and costs presented here may be 'peak of the market' estimates. If general cost levels return, for example, to those prevailing in 2005 to 2006 (by which time significant cost escalation had already occurred from previous levels), then costs of capture and compression for FOAK plants are expected to be US$110/tCO2 avoided (with a range of US$90-135/tCO2 avoided). For NOAK plants costs are expected to be US$25-50/tCO2. Based on these considerations a likely representative range of costs of abatement from CCS

  9. Target capture and target ghosts

    Science.gov (United States)

    Auerbach, Steven P.

    1996-05-01

    Optimal detection methods for small targets rely on whitened matched filters, which convolve the measured data with the signal model, and whiten the result with the noise covariance. In real-world implementations of such filters, the noise covariance must be estimated from the data, and the resulting covariance estimate may be corrupted by presence of the target. The resulting loss in SNR is called 'target capture'. Target capture is often thought to be a problem only for bright targets. This presentation shows that target capture also arises for dim targets, leading to an SNR loss which is independent of target strength and depends on the averaging method used to estimate the noise covariance. This loss is due to a 'coherent beat' between the true noise and that portion of the estimated noise covariance due to the target. This beat leads to 'ghost targets', which diminish the target SNR by producing a negative target ghost at the target's position. A quantitative estimate of this effect will be given, and shown to agree with numerical results. The effect of averaging on SNR is also discussed for data scenes with synthetic injected targets, in cases where the noise covariance is estimated using 'no target' data. For these cases, it is shown that the so-called 'optimal' filter, which uses the true noise covariance, is actually worse than a 'sub-optimal' filter which estimates the noise from scene. This apparent contradiction is resolved by showing that the optimal filter is best if the same filter is used for many scenes, but is outperformed by a filter adapted to a specific scene.

  10. Islamic Fasting and Diabetes

    Directory of Open Access Journals (Sweden)

    Fereidoun Azizi

    2013-07-01

    Full Text Available The aim of this article is to review health-related aspects of Ramadan fasting in normal individuals and diabetics. During fasting days of Ramadan, glucose homeostasis is maintained by meal taken bepore dawn and by liver glycogen stores. Changes in serum lipids are variable and defend on the quality and quantity of food consumption and changes in weight. Compliant, well controlled type 2 diabetics may observe Ramadan fasting; but fasting is not recommended for type 1, non complaint, poorly controlled and pregnant diabetics. Although Ramadan fasting is safe for all healthy individuals and well controlled diabetics, those with uncontrolled diabetics and diabetics with complications should consult physicians and follow scientific recommendations.

  11. Fast fission phenomena

    International Nuclear Information System (INIS)

    Experimental studies of fast fission phenomena are presented. The paper is divided into three parts. In the first part, problems associated with fast fission processes are examined in terms of interaction potentials and a dynamic model is presented in which highly elastic collisions, the formation of compound nuclei and fast fission appear naturally. In the second part, a description is given of the experimental methods employed, the observations made and the preliminary interpretation of measurements suggesting the occurence of fast fission processes. In the third part, our dynamic model is incorporated in a general theory of the dissipative processes studied. This theory enables fluctuations associated with collective variables to be calculated. It is applied to highly inelastic collisions, to fast fission and to the fission dynamics of compound nuclei (for which a schematic representation is given). It is with these calculations that the main results of the second part can be interpreted

  12. Islamic fasting and diabetes

    Directory of Open Access Journals (Sweden)

    Fereidoun Azizi

    2013-03-01

    Full Text Available The aim of this article is to review health-related aspects of Ramadan fasting in normal individuals and diabetics. During fasting days of Ramadan, glucose homeostasis is maintained by meal taken bepore dawn and by liver glycogen stores. Changes in serum lipids are variable and defend on the quality and quantity of food consumption and changes in weight. Compliant, well controlled type 2 diabetics may observe Ramadan fasting; but fasting is not recommended for type 1, non complaint, poorly controlled and pregnant diabetics. Although Ramadan fasting is safe for all healthy individuals and well controlled diabetics, those with uncontrolled diabetics and diabetics with complications should consult physicians and follow scientific recommendations.

  13. RFI Mitigation for FAST

    Science.gov (United States)

    Zhang, Haiyan; Nan, Rendong; Gan, Hengqian; Yue, Youling; Wu, Mingchang; Zhang, Zhiwei; Jin, Chengjin; Peng, Bo

    2015-08-01

    Five-hundred-meter Aperture Spherical radio Telescope (FAST) is a Chinese mega-science project to build the largest single dish radio telescope in the world. The construction was officially commenced in March 2011. The first light of FAST is expected in 2016. Due to the high sensitivity of FAST, Radio Frequency Interference (RFI) mitigation for the telescope is required to assure the realization of the scientific goals. In order to protect the radio environment of FAST site, the local government has established a radio quiet zone with 30 km radius. Moreover, Electromagnetic Compatibility (EMC) designs and measurements for FAST have also been carried out, and some examples, such as EMC designs for actuator and focus cabin, have been introduced briefly.

  14. Fast Spectrum Reactors

    CERN Document Server

    Todd, Donald; Tsvetkov, Pavel

    2012-01-01

    Fast Spectrum Reactors presents a detailed overview of world-wide technology contributing to the development of fast spectrum reactors. With a unique focus on the capabilities of fast spectrum reactors to address nuclear waste transmutation issues, in addition to the well-known capabilities of breeding new fuel, this volume describes how fast spectrum reactors contribute to the wide application of nuclear power systems to serve the global nuclear renaissance while minimizing nuclear proliferation concerns. Readers will find an introduction to the sustainable development of nuclear energy and the role of fast reactors, in addition to an economic analysis of nuclear reactors. A section devoted to neutronics offers the current trends in nuclear design, such as performance parameters and the optimization of advanced power systems. The latest findings on fuel management, partitioning and transmutation include the physics, efficiency and strategies of transmutation, homogeneous and heterogeneous recycling, in addit...

  15. Radiative kaon capture in hydrogen

    International Nuclear Information System (INIS)

    Negative kaons were stopped in liquid hydrogen to measure the radiative capture rates to Yγ final states. Branching ratios for the reactions K-p → Λγ and K-p → Σoγ provide information about the quark structure of the Λ(1404). Superior photon resolution is needed to distinguish the signal photons from the background of πo decay photons. Such resolution was provided by a NaI detector, which has a resolution of 1.3% (FWHM) near 300 MeV. A description of the experimental technique and data reduction is presented, along with preliminary branching ratio results

  16. Prey capture by harbour porpoises

    DEFF Research Database (Denmark)

    Verfuss, Ursula; Miller, Lee; Pilz, Peter;

    The harbor porpoise (Phocoena phocoena) is a small toothed whale living mostly in coastal waters.  There are large, but unknown, numbers in the inner Danish waters.  Four are in captivity at Fjord & Bælt, Kerteminde, Denmark, one of which was born here in 2007.  Harbor porpoises use their ultraso...... sequence ends in a terminal, high repetition rate buzz (>600 clicks/s) just before capturing the prey (a video will be shown).  The temporal sequence resembles that of beaked whales and bats...

  17. Fast processing of foreign fiber images by image blocking

    Directory of Open Access Journals (Sweden)

    Yutao Wu

    2014-08-01

    Full Text Available In the textile industry, it is always the case that cotton products are constitutive of many types of foreign fibers which affect the overall quality of cotton products. As the foundation of the foreign fiber automated inspection, image process exerts a critical impact on the process of foreign fiber identification. This paper presents a new approach for the fast processing of foreign fiber images. This approach includes five main steps, image block, image pre-decision, image background extraction, image enhancement and segmentation, and image connection. At first, the captured color images were transformed into gray-scale images; followed by the inversion of gray-scale of the transformed images ; then the whole image was divided into several blocks. Thereafter, the subsequent step is to judge which image block contains the target foreign fiber image through image pre-decision. Then we segment the image block via OSTU which possibly contains target images after background eradication and image strengthening. Finally, we connect those relevant segmented image blocks to get an intact and clear foreign fiber target image. The experimental result shows that this method of segmentation has the advantage of accuracy and speed over the other segmentation methods. On the other hand, this method also connects the target image that produce fractures therefore getting an intact and clear foreign fiber target image.

  18. The Effectiveness of Classroom Capture Technology

    Science.gov (United States)

    Ford, Maire B.; Burns, Colleen E.; Mitch, Nathan; Gomez, Melissa M.

    2012-01-01

    The use of classroom capture systems (systems that capture audio and video footage of a lecture and attempt to replicate a classroom experience) is becoming increasingly popular at the university level. However, research on the effectiveness of classroom capture systems in the university classroom has been limited due to the recent development and…

  19. Media capture in a democracy : the role of wealth concentration

    OpenAIRE

    Corneo, Giacomo

    2005-01-01

    Since objective news coverage is vital to democracy, captured media can seriously distort collective decisions. The current paper develops a voting model where citizens are uncertain about the welfare effects induced by alternative policy options and derive information about those effects from the mass media. The media might however secretly collude with interest groups in order to influence the public opinion. In the case of voting over the level of a productivity-enhancing public bad, it is...

  20. Counting with Combined Splitting and Capture-Recapture Methods

    CERN Document Server

    Dupuis, Paul; Ridder, Ad; Rubinstein, Reuven; Vaisman, Radislav

    2011-01-01

    We apply the splitting method to three well-known counting problems, namely 3-SAT, random graphs with prescribed degrees, and binary contingency tables. We present an enhanced version of the splitting method based on the capture-recapture technique, and show by experiments the superiority of this technique for SAT problems in terms of variance of the associated estimators, and speed of the algorithms.

  1. Capturing value from gas processing

    International Nuclear Information System (INIS)

    This paper reports that if you are looking for a way to create value, you may not have to look any further than your gas processing assets. Capturing value from gas processing may seem impossible, given the tough times the industry has been experiencing. But gas processing is moving into a new era and some early movers are already capitalizing on the opportunities being created. They are making real cuts in operating costs. They are not afraid of the R word (rationalization). And they are creating or strengthening attributes that give them a unique competitive advantage. What are these efforts worth? The authors estimate that they can increase the value of gas processing assets by up to 150 percent. For a typical 100 MMcfd processing facility, that could mean $100 million. If you want to make more from your gas processing assets, it is important to understand the forces that have been pushing the industry into a new era. You also need to take a closer look at what early movers are doing and the value creation opportunities for companies and the industry as a whole. All of that will provide a context for thinking about how your company can capture those opportunities

  2. Effect of dolomite decomposition under CO2 on its multicycle CO2 capture behaviour under calcium looping conditions.

    Science.gov (United States)

    de la Calle Martos, Antonio; Valverde, Jose Manuel; Sanchez-Jimenez, Pedro E; Perejón, Antonio; García-Garrido, Cristina; Perez-Maqueda, Luis A

    2016-06-28

    One of the major drawbacks that hinder the industrial competitiveness of the calcium looping (CaL) process for CO2 capture is the high temperature (∼930-950 °C) needed in practice to attain full calcination of limestone in a high CO2 partial pressure environment for short residence times as required. In this work, the multicycle CO2 capture performance of dolomite and limestone is analysed under realistic CaL conditions and using a reduced calcination temperature of 900 °C, which would serve to mitigate the energy penalty caused by integration of the CaL process into fossil fuel fired power plants. The results show that the fundamental mechanism of dolomite decomposition under CO2 has a major influence on its superior performance compared to limestone. The inert MgO grains resulting from dolomite decomposition help preserve a nanocrystalline CaO structure wherein carbonation in the solid-state diffusion controlled phase is promoted. The major role played by the dolomite decomposition mechanism under CO2 is clearly demonstrated by the multicycle CaO conversion behaviour observed for samples decomposed at different preheating rates. Limestone decomposition at slow heating rates yields a highly crystalline and poorly reactive CaCO3 structure that requires long periods to fully decarbonate and shows a severely reduced capture capacity in subsequent cycles. On the other hand, the nascent CaCO3 produced after dolomite half-decomposition consists of nanosized crystals with a fast decarbonation kinetics regardless of the preheating rate, thus fully decomposing from the very first cycle at a reduced calcination temperature into a CaO skeleton with enhanced reactivity as compared to limestone derived CaO. PMID:27253328

  3. Electron capture by highly charged low-velocity ions

    International Nuclear Information System (INIS)

    This paper describes the use of a fast heavy ion beam to produce, by bombardment of gaseous targets, highly-charged low-velocity recoil ions, and the use of these secondary ions in turn as projectiles in studies of electron capture and ionization in low-energy collision systems. The interest in collisions involving low-energy highly-charged projectiles comes both from the somewhat simplifying aspects of the physics which attend the long-range capture and from applications to fusion plasmas, astrophysics and more speculative technology such as the production of X-ray lasers. The ions of interest in such applications should have both electronic excitation and center-of-mass energies in the keV range and cannot be produced by simply stripping fast heavy ion beams. Several novel types of ion source have been developed to produce low-energy highly-charged ions, of which the secondary ion recoil source discussed in this paper is one. (Auth.)

  4. Genetic selection for fast growth generates bone architecture characterised by enhanced periosteal expansion and limited consolidation of the cortices but a diminution in the early responses to mechanical loading.

    OpenAIRE

    Rawlinson, S. C.; Murray, D. H.; Mosley, J. R.; Wright, C. D.; Bredl, J. C.; Saxon, L. K.; Loveridge, N; Leterrier, C.; Constantin, P.; Farquharson, C.; Pitsillides, A. A.

    2009-01-01

    Bone strength is, in part, dependent on a mechanical input that regulates the (re)modelling of skeletal elements to an appropriate size and architecture to resist fracture during habitual use. The rate of longitudinal bone growth in juveniles can also affect fracture incidence in adulthood, suggesting an influence of growth rate on later bone quality. We have compared the effects of fast and slow growth on bone strength and architecture in the tibiotarsi of embryonic and juvenile birds. The l...

  5. Fast Breeder Reactor studies

    International Nuclear Information System (INIS)

    This report is a compilation of Fast Breeder Reactor (FBR) resource documents prepared to provide the technical basis for the US contribution to the International Nuclear Fuel Cycle Evaluation. The eight separate parts deal with the alternative fast breeder reactor fuel cycles in terms of energy demand, resource base, technical potential and current status, safety, proliferation resistance, deployment, and nuclear safeguards. An Annex compares the cost of decommissioning light-water and fast breeder reactors. Separate abstracts are included for each of the parts

  6. Fasting and cognitive function.

    Science.gov (United States)

    Pollitt, E; Lewis, N L; Garza, C; Shulman, R J

    The effects of short-term fasting (skipping breakfast) on the problem-solving performance of 9 to 11 yr old children were studied under the controlled conditions of a metabolic ward. The behavioral test battery included an assessment of IQ, the Matching Familiar Figure Test and Hagen Central Incidental Test. Glucose and insulin levels were measured in blood. All assessments were made under fasting and non-fasting conditions. Skipping breakfast was found to have adverse effects on the children's late morning problem-solving performance. These findings support observations that the timing and nutrient composition of meals have acute and demonstrable effects on behavior. PMID:6764933

  7. Fast Breeder Reactor studies

    Energy Technology Data Exchange (ETDEWEB)

    Till, C.E.; Chang, Y.I.; Kittel, J.H.; Fauske, H.K.; Lineberry, M.J.; Stevenson, M.G.; Amundson, P.I.; Dance, K.D.

    1980-07-01

    This report is a compilation of Fast Breeder Reactor (FBR) resource documents prepared to provide the technical basis for the US contribution to the International Nuclear Fuel Cycle Evaluation. The eight separate parts deal with the alternative fast breeder reactor fuel cycles in terms of energy demand, resource base, technical potential and current status, safety, proliferation resistance, deployment, and nuclear safeguards. An Annex compares the cost of decommissioning light-water and fast breeder reactors. Separate abstracts are included for each of the parts.

  8. Capture of Irregular Satellites at Jupiter

    CERN Document Server

    Nesvorny, D; Deienno, R

    2014-01-01

    The irregular satellites of outer planets are thought to have been captured from heliocentric orbits. The exact nature of the capture process, however, remains uncertain. We examine the possibility that irregular satellites were captured from the planetesimal disk during the early Solar System instability when encounters between the outer planets occurred (Nesvorny, Vokrouhlicky & Morbidelli 2007, AJ 133; hereafter NVM07). NVM07 already showed that the irregular satellites of Saturn, Uranus and Neptune were plausibly captured during planetary encounters. Here we find that the current instability models present favorable conditions for capture of irregular satellites at Jupiter as well, mainly because Jupiter undergoes a phase of close encounters with an ice giant. We show that the orbital distribution of bodies captured during planetary encounters provides a good match to the observed distribution of irregular satellites at Jupiter. The capture efficiency for each particle in the original transplanetary d...

  9. Improved structural materials for fast breeder reactors

    International Nuclear Information System (INIS)

    Electricity plays a crucial role in the economic development of our country. Coal is the primary fuel for generation of electricity in India as in many other countries. In India, generation of power by nuclear reactors is very important because of (i) availability of large thorium resource, (ii) constraints on setting up of fossil fuel based power plants and (iii) the negligibly small green house gas emissions by nuclear energy. The nuclear programme of the country is being implemented in three stages: (i) pressurized heavy water reactors of the CANDU type, (ii) sodium-cooled fast reactors and (iii) thorium-based reactors. Sodium-cooled fast reactor (SFR) technology is envisioned to make use of the large thorium reserves available. India has undertaken and made rapid strides in developing SFR technology and building of fast reactors for energy generation. A Fast Breeder Test Reactor (FBTR) of 40 MWt is operating successfully for over 25 years at Indira Gandhi Centre for Atomic Research. Based on the design, construction and operational experience, a 500 MWe Prototype Fast Breeder Reactor (PFBR) has been designed indigenously and is in an advanced stage of construction. Its design is being further optimised for enhanced economy with respect to cost of electricity production, for use in commercial reactors. Currently, several R and D programmes are under implementation for the development of new materials required for improved economy of commercial fast reactors

  10. Electron capture and fragmentation in Ar11+ + CO collisions

    International Nuclear Information System (INIS)

    Collisions between 3, 10, and 50 keV/q Ar11+ ions and CO molecules have been studied using the Macdonald Lab CRYEBIS. Coincidence time of flight was used to detect all recoil ions and a position sensitive detector was used to determine final projectile charge states. Single- and double-electron capture are much larger than ionization at these collision energies. The dominant recoil channel associated with the Ar10+ final state is the CO+ molecular ion. The main ion-pair channel is the C+ + O+ dissociation of CO2+ while higher charge states of the transient COq+ fall off rapidly. Charge states up to CO4+ are formed in the collision indicating that many electrons are captured, but only one (and sometimes two) is retained by the projectile. This is due to autoionization of the highly excited states occupied by the captured electrons. In general, the fragmentation pattern of the CO molecule resembles the fragmentation associated with ionization caused by fast highly charged ions. This is as expected, since both processes happen at large impact parameters

  11. Re-capturing cosmic information

    CERN Document Server

    Seo, Hee-Jong; Dodelson, Scott; Jain, Bhuvnesh; Takada, Masahiro

    2010-01-01

    Gravitational lensing of distant galaxies can be exploited to infer the convergence field as a function of angular position on the sky. The statistics of this field, much like that of the cosmic microwave background (CMB), can be studied to extract information about fundamental parameters in cosmology, most notably the dark energy in the Universe. Unlike the CMB, the distribution of matter in the Universe which determines the convergence field is highly non-Gaussian, reflecting the nonlinear processes which accompanied structure formation. Much of the cosmic information contained in the initial field is therefore unavailable to the standard power spectrum measurements. Here we propose a method for re-capturing cosmic information by using the power spectrum of a simple function of the observed (nonlinear) convergence field. We adapt the approach of Neyrinck et al. (2009) to lensing by using a modified logarithmic transform of the convergence field. The Fourier transform of the log-transformed field has modes t...

  12. Neutron capture therapy for melanoma

    International Nuclear Information System (INIS)

    The development of boron-containing compounds which localize selectively in tumor may require a tumor-by-tumor type of approach that exploits any metabolic pathways unique to the particular type of tumor. Melanin-producing melanomas actively transport and metabolize aromatic amino acids for use as precursors in the synthesis of the pigment melanin. It has been shown that the boron-containing amino acid analog p-borono-phenylalanine (BPA) is selectively accumulated in melanoma tissue, producing boron concentrations in tumor that are within the range estimated to be necessary for successful boron neutron capture therapy (BNCT). We report here the results of therapy experiments carried out at the Brookhaven Medical Research Reactor (BMRR). 21 refs., 5 figs., 3 tabs

  13. Muon capture by helium-3

    International Nuclear Information System (INIS)

    In this paper we study the capture of a negative muon by He3 in the channel μ-+He3+V. Following Primakoff we use the V-A theory of the weak interactions. We include also first order relativistic terms. To describe the initial and final nuclei we have used the most general wave function allowed by the Paul is exclusion principle, assuming that these nuclei are a mixture of an isospin doublet and quadruplet. For the part of the wave function depending on the inter nucleonic distances, we have taken four different function without hard-core, a gaussian and three kinds of Irving type. We present in several tables the results obtained varying gp/gv and gA/gy as well as the amplitudes of the fourteen terms forming the nuclear wave function. (Author) 35 refs

  14. Laser Capture Microdissection in Dentistry

    Directory of Open Access Journals (Sweden)

    Uraiwan Chokechanachaisakul

    2010-01-01

    Full Text Available Laser capture microdissection (LCM allows for the microscopic procurement of specific cell types from tissue sections that can then be used for gene expression analysis. According to the recent development of the LCM technologies and methodologies, the LCM has been used in various kinds of tissue specimens in dental research. For example, the real-time polymerase-chain reaction (PCR can be performed from the formaldehyde-fixed, paraffin-embedded, and immunostained sections. Thus, the advance of immuno-LCM method allows us to improve the validity of molecular biological analysis and to get more accurate diagnosis in pathological field in contrast to conventional LCM. This paper is focused on the presentation and discussion of the existing literature that covers the fields of RNA analysis following LCM in dentistry.

  15. Opportunity Captures 'Lion King' Panorama

    Science.gov (United States)

    2004-01-01

    [figure removed for brevity, see original site] Click on the image for Opportunity Captures 'Lion King' Panorama (QTVR) This approximate true-color panorama, dubbed 'Lion King,' shows 'Eagle Crater' and the surrounding plains of Meridiani Planum. It was obtained by the Mars Exploration Rover Opportunity's panoramic camera on sols 58 and 60 using infrared (750-nanometer), green (530-nanometer) and blue (430-nanometer) filters. This is the largest panorama obtained yet by either rover. It was taken in eight segments using six filters per segment, for a total of 558 images and more than 75 megabytes of data. Additional lower elevation tiers were added to ensure that the entire crater was covered in the mosaic. This panorama depicts a story of exploration including the rover's lander, a thorough examination of the outcrop, a study of the soils at the near-side of the lander, a successful exit from Eagle Crater and finally the rover's next desination, the large crater dubbed 'Endurance'.

  16. Cage-based performance capture

    CERN Document Server

    Savoye, Yann

    2014-01-01

    Nowadays, highly-detailed animations of live-actor performances are increasingly easier to acquire and 3D Video has reached considerable attentions in visual media production. In this book, we address the problem of extracting or acquiring and then reusing non-rigid parametrization for video-based animations. At first sight, a crucial challenge is to reproduce plausible boneless deformations while preserving global and local captured properties of dynamic surfaces with a limited number of controllable, flexible and reusable parameters. To solve this challenge, we directly rely on a skin-detached dimension reduction thanks to the well-known cage-based paradigm. First, we achieve Scalable Inverse Cage-based Modeling by transposing the inverse kinematics paradigm on surfaces. Thus, we introduce a cage inversion process with user-specified screen-space constraints. Secondly, we convert non-rigid animated surfaces into a sequence of optimal cage parameters via Cage-based Animation Conversion. Building upon this re...

  17. High efficiency nanocomposite sorbents for CO2 capture based on amine-functionalized mesoporous capsules

    KAUST Repository

    Qi, Genggeng

    2011-01-01

    A novel high efficiency nanocomposite sorbent for CO2 capture has been developed based on oligomeric amine (polyethylenimine, PEI, and tetraethylenepentamine, TEPA) functionalized mesoporous silica capsules. The newly synthesized sorbents exhibit extraordinary capture capacity up to 7.9 mmol g-1 under simulated flue gas conditions (pre-humidified 10% CO 2). The CO2 capture kinetics were found to be fast and reached 90% of the total capacities within the first few minutes. The effects of the mesoporous capsule features such as particle size and shell thickness on CO2 capture capacity were investigated. Larger particle size, higher interior void volume and thinner mesoporous shell thickness all improved the CO2 capacity of the sorbents. PEI impregnated sorbents showed good reversibility and stability during cyclic adsorption-regeneration tests (50 cycles). © 2011 The Royal Society of Chemistry.

  18. Capture by aerogel-characterization of mobile dust in tokamak scrape-off layer plasmas

    International Nuclear Information System (INIS)

    The aim of this letter is to demonstrate the feasibility and potential of the novel in situ dust diagnostic method-capture by aerogel targets. Aerogel, a highly porous material with a density of a few tens of kg m-3, allows capturing of dust particles present during the discharge without destroying them. The first exposures in the TEXTOR scrape-off layer plasma showed that such targets are able to capture both slow and fast particles with sizes in the range from submicrometre to ∼100 μm. The technique provides information on dust velocity and size distribution as well as dust flux estimates. The composition and texture of the captured dust can also be studied in detail to shed light on dust formation processes.

  19. FastStats: Diabetes

    Science.gov (United States)

    ... State and Territorial Data Reproductive Health Contraceptive Use Infertility Reproductive Health FastStats Mobile Application Get Email Updates ... Links Ambulatory Health Care Data National Health and Nutrition Examination Survey National Health Interview Survey National Home ...

  20. FastStats: Osteoporosis

    Science.gov (United States)

    ... State and Territorial Data Reproductive Health Contraceptive Use Infertility Reproductive Health FastStats Mobile Application Get Email Updates ... PDF - 241 KB] Related Links National Health and Nutrition Examination Survey Centers for Disease Control and Prevention: ...

  1. CMS Fast Facts

    Data.gov (United States)

    U.S. Department of Health & Human Services — CMS has developed a new quick reference statistical summary on annual CMS program and financial data. CMS Fast Facts includes summary information on total program...

  2. Brug af faste vendinger

    DEFF Research Database (Denmark)

    Bergenholtz, Henning; Bjærge, Esben

    Ordbogen indelholder tekstproduktionsangivelser til ca. 17.000 idiomer, ordsprog, bevingede ord og andre faste vendinger. Det drejer sig bl.a. om angivelser til betydningen, grammatik, kollokationer, eksempler, synonymer og antonymer....

  3. Fast neutrons dosimetry

    International Nuclear Information System (INIS)

    A proton recoil technique has been developed for inducing thermoluminescence with incident fast neutrons. CaF2 was used as the TL phosphor, and cane sugar and polyethylene were used as proton radiators. The phosphor and the hydrogeneous material powders were well mixed, encapsulated in glass tubes and exposed to Am-Be sources, resulting in recoils from incident fast neutrons of energy between 0,25 and 11,25 MeV. The intrinsic response of pure CaF2 to fast neutrons without a hydrogeneous radiator was checked by using LiF (TLD-700). Glow curves were recorded from room temperature up to 3500C after different doses of neutrons and gamma rays of 60Co. First collision dose due to fast neutrons in tissue like materials such as cane sugar and polyethylene was also calculated

  4. Helios: resonance capture in zirconium

    International Nuclear Information System (INIS)

    Recently, natural Zr with resonance-shielding data has been added as a new nuclide to the nuclear-data library of the lattice code HELIOS. This has made it possible to study the importance of resonance shielding by Zr in lattice calculation. Usually, resonance shielding by Zr is neglected because it is a weak absorber. Many lattice codes cannot even treat resonance capture in the clad and even less so in the shroud a WWER, the channel of a BWR, the pressure and calandria tubes of a CANDU, or the pressure tube of an RBMK. This paper shows for some lattice types the effect of resonance shielding by Zr and presents a detailed analysis for SVEA and WWER-440 fuel. Because resonance shielding reduces neutron capture, it increases reactivity. In Zr it occurs mainly in the Zr-91 resonances at 293 and 681 e V, and the Zr-96 resonance at 301 eV, with peaks of 250 b, and 1050 b. Its effect increases when the spectrum hardens, e.g. for SVEA fuel the reactivity increase depends on the void and on whetter the control blades are inserted or not--for uncontrolled at 40% steam void it varies from 160 to 190 pcm between 0 and 50 M Wd/kg. For WWER fuel with ppm B it varies from 180 to 260 pcm. In CANDU fuel, which has a soft spectrum but contains much Zr, the reactivity increase is about 230 pcm. For RBMK fuel it is about 340 pcm, and for an old uncontrolled 8 x 8 BWR assembly it is about 200 and 380 pcm at 0 and 70% steam void (Authors)

  5. Mercury capture by native fly ash carbons in coal-fired power plants.

    Science.gov (United States)

    Hower, James C; Senior, Constance L; Suuberg, Eric M; Hurt, Robert H; Wilcox, Jennifer L; Olson, Edwin S

    2010-08-01

    The control of mercury in the air emissions from coal-fired power plants is an on-going challenge. The native unburned carbons in fly ash can capture varying amounts of Hg depending upon the temperature and composition of the flue gas at the air pollution control device, with Hg capture increasing with a decrease in temperature; the amount of carbon in the fly ash, with Hg capture increasing with an increase in carbon; and the form of the carbon and the consequent surface area of the carbon, with Hg capture increasing with an increase in surface area. The latter is influenced by the rank of the feed coal, with carbons derived from the combustion of low-rank coals having a greater surface area than carbons from bituminous- and anthracite-rank coals. The chemistry of the feed coal and the resulting composition of the flue gas enhances Hg capture by fly ash carbons. This is particularly evident in the correlation of feed coal Cl content to Hg oxidation to HgCl2, enhancing Hg capture. Acid gases, including HCl and H2SO4 and the combination of HCl and NO2, in the flue gas can enhance the oxidation of Hg. In this presentation, we discuss the transport of Hg through the boiler and pollution control systems, the mechanisms of Hg oxidation, and the parameters controlling Hg capture by coal-derived fly ash carbons. PMID:24223466

  6. FAST Maser Surveys

    Indian Academy of Sciences (India)

    J. S. Zhang

    2014-09-01

    FAST, the Five-hundred meter Aperture Spherical radio Telescope, will become the largest operating single-dish telescope in the coming years. It has many advantages: much better sensitivity for its largest collecting area; large sky coverage due to its innovative design of the active primary surface; extremely radio quiet from its unique location, etc. In this work, I will highlight the future capabilities of FAST to discover and observe both galactic and extragalactic masers.

  7. Discovery with FAST

    Science.gov (United States)

    Wilkinson, P.

    2016-02-01

    FAST offers "transformational" performance well-suited to finding new phenomena - one of which might be polarised spectral transients. But discoveries will only be made if "the system" provides its users with the necessary opportunities. In addition to designing in as much observational flexibility as possible, FAST should be operated with a philosophy which maximises its "human bandwidth". This band includes the astronomers of tomorrow - many of whom not have yet started school or even been born.

  8. Fast parametrized biorthogonal transforms

    OpenAIRE

    Puchala, Dariusz; Yatsymirsyy, Mykhaylo

    2011-01-01

    W pracy zaproponowano schemat syntezy szybkich parametryzowanych przekształceń biortogonalnych oparty o diagramy przepływowe dla szybkich przekształceń ortonormalnych i dwupunktowe biortogonalne operatory motylkowe. In this paper the authors propose the technique ot synthesis of fast parametrised biorthogonal transforms that takes advantage of data-flow graphs for calculation of fast orthonormal transforms and two-point biorthogonal butterfly operators.

  9. Fast Statistical Alignment

    OpenAIRE

    Bradley, Robert K.; Adam Roberts; Michael Smoot; Sudeep Juvekar; Jaeyoung Do; Colin Dewey; Ian Holmes; Lior Pachter

    2009-01-01

    We describe a new program for the alignment of multiple biological sequences that is both statistically motivated and fast enough for problem sizes that arise in practice. Our Fast Statistical Alignment program is based on pair hidden Markov models which approximate an insertion/deletion process on a tree and uses a sequence annealing algorithm to combine the posterior probabilities estimated from these models into a multiple alignment. FSA uses its explicit statistical model to produce multi...

  10. Fasting and Urinary Stones

    Directory of Open Access Journals (Sweden)

    Ali Shamsa

    2013-11-01

    Full Text Available Introduction: Fasting is considered as one of the most important practices of Islam, and according to Prophet Mohammad, fasting is obligatory upon Muslims. The aim of this study is to evaluate the effects of fasting on urinary stones. Materials and Methods: Very few studies have been carried out on urinary stones and the effect of Ramadan fasting. The sources of the present study are Medline and articles presented by local and Muslim researchers. Meanwhile, since we are acquainted with three well-known researchers in the field of urology, we contacted them via email and asked for their professional opinions. Results: The results of studies about the relationship of urinary stones and their incidence in Ramadan are not alike, and are even sometimes contradictory. Some believe that increased incidence of urinary stones in Ramadan is related not to fasting, but to the rise of weather temperature in hot months, and an increase in humidity. Conclusion: Numerous biological and behavioral changes occur in people who fast in Ramadan and some researchers believe that urinary stone increases during this month.

  11. Fasting and urinary stones

    Directory of Open Access Journals (Sweden)

    Ali Shamsa

    2013-12-01

    Full Text Available Introduction: Fasting is considered as one of the most important practices of Islam, and according to Prophet Mohammad, fasting is obligatory upon Muslims. The aim of this study is to evaluate the effects of fasting on urinary stones. Materials and Methods:Very few studies have been carried out on urinary stones and the effect of Ramadan fasting. The sources of the present study are Medline and articles presented by local and Muslim researchers. Meanwhile, since we are acquainted with three well-known researchers in the field  of urology, we contacted them via email and asked for their professional opinions. Results:The results of studies about the relationship of urinary stones and their incidence in Ramadan are not alike, and are even sometimes contradictory. Some believe that increased incidence of urinary stones in Ramadan is related not to fasting, but to the rise of weather temperature in hot months, and an increase in humidity. Conclusion: Numerous biological and behavioral changes occur in people who fast in Ramadan and some researchers believe that urinary stone increases during this month.

  12. FastKwic, an "Intelligent" Concordancer using FASTR

    OpenAIRE

    Lux-Pogodalla, Veronika; Besagni, Dominique; Fort, Karën

    2010-01-01

    6 p International audience In this paper, we introduce the FastKwic (Key Word In Context using FASTR), a new concordancer for French and English that does not require users to learn any particular request language. Built on FASTR, it shows them not only occurrences of the searched term but also of several morphological, morpho-syntactic and syntactic variants (for example, image enhancement, enhancement of image, enhancement of fingerprint image, image texture enhancement). Fastkwic is ...

  13. Degrading the Plutonium Produced in Fast Breeder Reactor Blankets

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jor-Shan; Kuno, Yusuke [Tokyo University, 7-3-1, Hongo, Bunkyo-ku, Tokyo, 113-8656 (Japan)

    2009-06-15

    enhance the production of {sup 238}Pu. However, using recycled uranium as blanket fuel may degrade the neutron economy (as two neutron-captures are required by produce {sup 238}Pu). Another option is to fuel the blanket with thorium and uranium (natural or depleted) oxide. The intent here is to facilitate a controlled production of denatured uranium with about 5% or 20% {sup 233}U in total uranium discharged from the breeder blanket by innovative fuel design. The outcome of this option is to produce 5%-enriched uranium (in {sup 233}U) which can be used as fuel for LWRs, or 20%-enriched uranium (in {sup 233}U) to be used as driver fuel in fast reactor cores. The challenge for this option is to deal with the presence of high radiation from {sup 232}U and its decay daughters which could complicate its use as fresh fuel for LWRs and fast reactors. This paper addresses the pros and cons of these options of degrading the breeder blanket plutonium, and discusses their effectiveness for proliferation resistance. References 1. M. Saito, H. Sagara, and Y. Peryoga, 'Development of Innovative Nuclear Technology to Produce Protected Plutonium with High Proliferation Resistance - Grand Design of Project', Trans. ANS Winter Meeting, Washington DC, Nov. 2004. 2. H. Sagara, M. Saito, Y. Peryoga, A. Ezoubtchenko, and A. Takivayev, 'Denaturing of Plutonium by Transmutation of Minor-Actinides for Enhancement of Proliferation Resistance', Journal of Nuclear Science and Technology, Vol. 42, No.2, pp. 161-168, February 2005. 3. M. Saito, 'Multi-component Self-consistent Nuclear Energy System: Protected Plutonium Production (P3)', Int. J. Nuclear Energy Science and Technology, Vol.1, No. 2/3, 2005. (authors)

  14. MOEMS-based time-of-flight camera for 3D video capturing

    Science.gov (United States)

    You, Jang-Woo; Park, Yong-Hwa; Cho, Yong-Chul; Park, Chang-Young; Yoon, Heesun; Lee, Sang-Hun; Lee, Seung-Wan

    2013-03-01

    We suggest a Time-of-Flight (TOF) video camera capturing real-time depth images (a.k.a depth map), which are generated from the fast-modulated IR images utilizing a novel MOEMS modulator having switching speed of 20 MHz. In general, 3 or 4 independent IR (e.g. 850nm) images are required to generate a single frame of depth image. Captured video image of a moving object frequently shows motion drag between sequentially captured IR images, which results in so called `motion blur' problem even when the frame rate of depth image is fast (e.g. 30 to 60 Hz). We propose a novel `single shot' TOF 3D camera architecture generating a single depth image out of synchronized captured IR images. The imaging system constitutes of 2x2 imaging lens array, MOEMS optical shutters (modulator) placed on each lens aperture and a standard CMOS image sensor. The IR light reflected from object is modulated by optical shutters on the apertures of 2x2 lens array and then transmitted images are captured on the image sensor resulting in 2x2 sub-IR images. As a result, the depth image is generated with those simultaneously captured 4 independent sub-IR images, hence the motion blur problem is canceled. The resulting performance is very useful in the applications of 3D camera to a human-machine interaction device such as user interface of TV, monitor, or hand held devices and motion capturing of human body. In addition, we show that the presented 3D camera can be modified to capture color together with depth image simultaneously on `single shot' frame rate.

  15. Inorganic membranes for carbon capture and power generation

    Science.gov (United States)

    Snider, Matthew T.

    of the templating agent. This meant that small restrictions in the micropores were beneficial to the transport of molecules with some attraction to the micropore walls. Further evidence of this effect were discovered in transport studies on Zeolite Y membranes, in which small amounts of residual water were observed to enhance the CO2 permeance in a similar way as the templating agent in the powder. However, the effect was only observed for dry CO 2 streams and previously humidified membranes. H2O affinity for the zeolite framework was so high and mobility in the micropores was so low that even 0.8 mol% H2O included in the gas stream was enough to reduce CO2 transport by 100x. This poses a serious concern for carbon capture by zeolite Y membrane in coal-fired power plants: the waste stream must be dehumidified first. In the long-term, raising the efficiencies of fossil-fuel power plants is preferable to post-combustion capture for cost- and resource-effective carbon emissions reduction. Supplementing combustion of the fuel with electrochemical conversion by solid oxide fuel cell (SOFC) shows promise in this effort. Thin-film (designs, with improved stability and quick ramp times. Low operating temperatures also provide the potential for fast, high-volume production, but so far high-performing LT-SOFCs have all been made by micro-fabrication methods. In this work, thin-film LT-SOFC modules were fabricated by colloidal processing and their performance was demonstrated. Nano-particulate colloid syntheses, dip-coating, and rapid thermal processing methods yielded fine-particle membrane microstructures, with high porosity and conductivity in the platinum/gadolinium-doped ceria (GDC) composite electrodes and density in the yttria-stabilized zirconia (YSZ) electrolytes. Power densities of >1000 W/m2 at 450°C and ˜5000 W/m2 at 600°C were achieved, and the modules ran >100hrs at peak power after 8 thermal cycles. Thus it was demonstrated that high performing LT-SOFCs can be

  16. Development Trends in Porous Adsorbents for Carbon Capture.

    Science.gov (United States)

    Sreenivasulu, Bolisetty; Sreedhar, Inkollu; Suresh, Pathi; Raghavan, Kondapuram Vijaya

    2015-11-01

    Accumulation of greenhouse gases especially CO2 in the atmosphere leading to global warming with undesirable climate changes has been a serious global concern. Major power generation in the world is from coal based power plants. Carbon capture through pre- and post- combustion technologies with various technical options like adsorption, absorption, membrane separations, and chemical looping combustion with and without oxygen uncoupling have received considerable attention of researchers, environmentalists and the stake holders. Carbon capture from flue gases can be achieved with micro and meso porous adsorbents. This review covers carbonaceous (organic and metal organic frameworks) and noncarbonaceous (inorganic) porous adsorbents for CO2 adsorption at different process conditions and pore sizes. Focus is also given to noncarbonaceous micro and meso porous adsorbents in chemical looping combustion involving insitu CO2 capture at high temperature (>400 °C). Adsorption mechanisms, material characteristics, and synthesis methods are discussed. Attention is given to isosteric heats and characterization techniques. The options to enhance the techno-economic viability of carbon capture techniques by integrating with CO2 utilization to produce industrially important chemicals like ammonia and urea are analyzed. From the reader's perspective, for different classes of materials, each section has been summarized in the form of tables or figures to get a quick glance of the developments. PMID:26422294

  17. A semi-quantitative equivalence for abstracting from fast reactions

    CERN Document Server

    Galpin, Vashti; Ciocchetta, Federica; 10.4204/EPTCS.67.5

    2011-01-01

    Semantic equivalences are used in process algebra to capture the notion of similar behaviour, and this paper proposes a semi-quantitative equivalence for a stochastic process algebra developed for biological modelling. We consider abstracting away from fast reactions as suggested by the Quasi-Steady-State Assumption. We define a fast-slow bisimilarity based on this idea. We also show congruence under an appropriate condition for the cooperation operator of Bio-PEPA. The condition requires that there is no synchronisation over fast actions, and this distinguishes fast-slow bisimilarity from weak bisimilarity. We also show congruence for an operator which extends the reactions available for a species. We characterise models for which it is only necessary to consider the matching of slow transitions and we illustrate the equivalence on two models of competitive inhibition.

  18. Earth--Mars Transfers with Ballistic Capture

    CERN Document Server

    Topputo, Francesco

    2014-01-01

    We construct a new type of transfer from the Earth to Mars, which ends in ballistic capture. This results in a substantial savings in capture $\\Delta v$ from that of a classical Hohmann transfer under certain conditions. This is accomplished by first becoming captured at Mars, very distant from the planet, and then from there, following a ballistic capture transfer to a desired altitude within a ballistic capture set. This is achieved by manipulating the stable sets, or sets of initial conditions whose orbits satisfy a simple definition of stability. This transfer type may be of interest for Mars missions because of lower capture $\\Delta v$, moderate flight time, and flexibility of launch period from the Earth.

  19. A survey of the Carbon Capture

    International Nuclear Information System (INIS)

    The concentration of carbon dioxide, one of the most important representatives of greenhouse gases in the atmosphere continues to rise. Fossil fuels burned in thermal power plants currently represent 80% of total energy production around the world and are the largest point sources of CO2, accounting for approximately 40% of total CO2 emissions. There are several options for reducing CO2 emissions: reducing demand, improving production efficiency and carbon capture and storage (CCS, carbon capture and storage). Capture and storage of carbon dioxide is generally a three-step process: 1st Capture and compression of combustion products, 2nd transport (mostly pipeline) and 3rd utilization (eg. production of urea, beverage industry, production of dry ice, etc.). Technologies for CO2 capturing used in power plants burning fossil fuels can be divided into four groups, each of which requires a completely different approach to CO2 capture.

  20. Monte Carlo calculations of fast effects in uranium graphite lattices

    International Nuclear Information System (INIS)

    Details are given of the results of a series of computations of fast neutron effects in natural uranium metal/graphite cells. The computations were performed using the Monte Carlo code SPEC. It is shown that neutron capture in U238 is conveniently discussed in terms of a capture escape probability ζ as well as the conventional probability p. The latter is associated with the slowing down flux and has the classical exponential dependence on fuel-to-moderator volume ratio whilst the former is identified with the component of neutron flux above 1/E. (author)

  1. Measurements of neutron capture cross sections

    International Nuclear Information System (INIS)

    A review of measurement techniques for the neutron capture cross sections is presented. Sell transmission method, activation method, and prompt gamma-ray detection method are described using examples of capture cross section measurements. The capture cross section of 238U measured by three different prompt gamma-ray detection methods (large liquid scintillator, Moxon-Rae detector, and pulse height weighting method) are compared and their discrepancies are resolved. A method how to derive the covariance is described. (author)

  2. Neutron capture cross section measurement techniques

    International Nuclear Information System (INIS)

    A review of currently-used techniques to measure neutron capture cross sections is presented. Measurements involving use of total absorption and Moxon-Rae detectors are based on low-resolution detection of the prompt γ-ray cascades following neutron captures. In certain energy ranges activation methods are convenient and useful. High resolution γ-ray measurements with germanium detectors can give information on the parameters of resonance capture states. The use of these techniques is described. (U.S.)

  3. Silica Aerogel Captures Cosmic Dust Intact

    Science.gov (United States)

    Tsou, P.

    1994-01-01

    The mesostructure of silica aerogel resembles stings of grapes, ranging in size from 10 to 100 angstrom. This fine mesostructure transmits nearly 90 percent of incident light in the visible, while providing sufficiently gentle dissipation of the kinetric energy of hypervelocity cosmic dust particles to permit their intact capture. We introduced silica aerogel in 1987 as capture medium to take advantage of its low density, fine mesostruicture and most importantly, its transparency, allowing optical location of captured micron sized particles.

  4. Plasma spectroscopy in the presence of fast particles

    International Nuclear Information System (INIS)

    The influence of monoenergetic fast charged particles present in a Maxwellian plasma on excitation and ionization processes is studied in the context of plasmas and fast particle diagnostics. It is shown that the influence can be significant for relative fast-particle densities as low as 10-4. On the other hand, the indirect influence through secondary electrons is found to be small in an approximate analytical calculation. Allowed transitions are significantly enhanced in the presence of fast particles while spin-forbidden excitations are hardly affected. Although the limiting conditions for LTE, partial LTE or corona equilibria are nearly unaltered, the populations of highly excited states are enhanced. Under partial-LTE conditions, this enhancement occurs without significantly influencing the relative populations of these upper levels. Illustrative calculations on the intensities and intensity ratios for outer and inner shell lines of diagnostic interest are presented

  5. Fasting in Ramadan with an insulin pump.

    Science.gov (United States)

    Kesavadev, Jothydev

    2015-05-01

    A good majority of subjects with diabetes on insulin therapies observe fasting during Ramadan. The challenge for the physician and the patient is to manage diabetes without an interruption to fasting by avoiding hypoglycaemia and simultaneously ensuring that blood glucose remain at acceptable safe levels. Insulin Pumps differ from syringes and insulin pens in that it offers a variable basal rate, different type of boluses and associated calculators. The technological advances that pumps offer, help educated subjects pre-programme a reduced basal rate throughout the day. Pumps ensure avoidance of hypoglycaemia and hyperglycaemia and preserve quality of life and enhance confidence in patients during fasting. Due to multiple benefits, insulin pumps are considered the best delivery systems for insulin during the holy month of Ramadan, despite the prerequisites for its optimal output and cost concerns. PMID:26013786

  6. Integral fast reactor safety features

    International Nuclear Information System (INIS)

    The Integral Fast Reactor (IFR) is an advanced liquid-metal-cooled reactor concept being developed at Argonne National Laboratory. The two major goals of the IFR development effort are improved economics and enhanced safety. In addition to liquid metal cooling, the principal design features that distinguish the IFR are: (1) a pool-type primary system, (2) an advanced ternary alloy metallic fuel, and (3) an integral fuel cycle with on-site fuel reprocessing and fabrication. This paper focuses on the technical aspects of the improved safety margins available in the IFR concept. This increased level of safety is made possible by (1) the liquid metal (sodium) coolant and pool-type primary system layout, which together facilitate passive decay heat removal, and (2) a sodium-bonded metallic fuel pin design with thermal and neutronic properties that provide passive core responses which control and mitigate the consequences of reactor accidents

  7. Neutron Capture Experiments on Unstable Nuclei

    International Nuclear Information System (INIS)

    The overall objective of this project is the measurement of neutron capture cross sections of importance to stewardship science and astrophysical modeling of nucleosynthesis, while at the same time helping to train the next generation of scientists with expertise relevant to U.S. national nuclear security missions and to stewardship science. A primary objective of this project is to study neutron capture cross sections for various stable and unstable isotopes that will contribute to the Science Based Stockpile Stewardship (SBSS) program by providing improved data for modeling and interpretation of nuclear device performance. Much of the information obtained will also be important in astrophysical modeling of nucleosynthesis. Measurements of these neutron capture cross sections are being conducted in collaboration with researchers at the Los Alamos Neutron Science Center (LANSCE) facility using the unique Detector for Advanced Neutron Capture Experiments (DANCE). In our early discussions with the DANCE group, decisions were made on the first cross sections to be measured and how our expertise in target preparation, radiochemical separations chemistry, and data analysis could best be applied. The initial emphasis of the project was on preparing suitable targets of both natural and separated stable europium isotopes in preparation for the ultimate goal of preparing a sufficiently large target of radioactive 155Eu (t1/2 = 4.7 years) and other radioactive and stable species for neutron cross-section measurements at DANCE. Our Annual Report, ''Neutron Capture Experiments on Unstable Nuclei'' by J. M. Schwantes, R. Sudowe, C. M. Folden III, H. Nitsche, and D. C. Hoffman, submitted to NNSA in December 2003, gives details about the initial considerations and scope of the project. During the current reporting period, electroplated targets of natural Eu together with valuable, stable, and isotopically pure 151Eu and 153Eu, and isotopically separated 154Sm were measured for

  8. Tracking fast neutrons

    International Nuclear Information System (INIS)

    Both neutron absorption and elastic scattering can be used to measure neutron momentum. Based on elastic collisions, the linear momentum of a fast neutron can be measured from as few as two consecutive recoil ion tracks plus the vertex position of the third collision, or ‘two and half’ ion tracks. If the time delay between the first two consecutive ion tracks is also measured, the number of ion tracks can be reduced to one and a half. The angular and magnitude resolutions are limited by ion range straggling to about 10%. Multi-wire proportional chambers and light-field imaging can be used for fast neutron tracking. Light-field imaging is free of charge-diffusion-induced image blur, but the limited number of photons available can be a challenge. 1H, 2H and 3He could be used for the initial development of fast neutron trackers based on light-field imaging. -- Highlights: • We describe the basic principle of fast neutron tracking through elastic collisions and absorption; • We calculate tracking errors, which are limited by ion range straggling. • Multi-wire proportional chamber and light field imaging are discussed for fast neutron tracking; • Time projection of ion tracks can be achieved by detecting photons

  9. Fast wave current drive

    International Nuclear Information System (INIS)

    Experiments on the fast wave in the range of high ion cyclotron harmonics in the ACT-1 device show that current drive is possible with the fast wave just as it is for the lower hybrid wave, except that it is suitable for higher plasma densities. A 1400 loop antenna launched the high ion cyclotron harmonic fast wave [ω/Ω = O(10)] into a He+ plasma with n/sub e/approx. =4 x 1012 cm-3 and B = 4.5 kG. Probe and magnetic loop diagnostics and FIR laser scattering confirmed the presence of the fast wave, and the Rogowski loop indicated that the circulating plasma current increased by up to 40A with 1 kW of coupled power, which is comparable to lower hybrid current drive in the same device with the same unidirectional fast electron beam used as the target for the RF. A phased antenna array would be used for FWCD in a tokamak without the E-beam

  10. Fast reactor programme

    International Nuclear Information System (INIS)

    This progress report summarizes the fast reactor research carried out by ECN during the period covering the year 1980. This research is mainly concerned with the cores of sodium-cooled breeders, in particular the SNR-300, and its related safety aspects. It comprises six items: A programme to determine relevant nuclear data of fission- and corrosion-products; A fuel performance programme comprising in-pile cladding failure experiments and a study of the consequences of loss-of-cooling and overpower; Basic research on fuel; Investigation of the changes in the mechanical properties of austenitic stainless steel DIN 1.4948 due to fast neutron doses, this material has been used in the manufacture of the reactor vessel and its internal components; Study of aerosols which could be formed at the time of a fast reactor accident and their progressive behaviour on leaking through cracks in the concrete containment; Studies on heat transfer in a sodium-cooled fast reactor core. As fast breeders operate at high power densities, an accurate knowledge of the heat transfer phenomena under single-phase and two-phase conditions is sought. (Auth.)

  11. Imprints of fast-rotating massive stars in the Galactic Bulge.

    Science.gov (United States)

    Chiappini, Cristina; Frischknecht, Urs; Meynet, Georges; Hirschi, Raphael; Barbuy, Beatriz; Pignatari, Marco; Decressin, Thibaut; Maeder, André

    2011-04-28

    The first stars that formed after the Big Bang were probably massive, and they provided the Universe with the first elements heavier than helium ('metals'), which were incorporated into low-mass stars that have survived to the present. Eight stars in the oldest globular cluster in the Galaxy, NGC 6522, were found to have surface abundances consistent with the gas from which they formed being enriched by massive stars (that is, with higher α-element/Fe and Eu/Fe ratios than those of the Sun). However, the same stars have anomalously high abundances of Ba and La with respect to Fe, which usually arises through nucleosynthesis in low-mass stars (via the slow-neutron-capture process, or s-process). Recent theory suggests that metal-poor fast-rotating massive stars are able to boost the s-process yields by up to four orders of magnitude, which might provide a solution to this contradiction. Here we report a reanalysis of the earlier spectra, which reveals that Y and Sr are also overabundant with respect to Fe, showing a large scatter similar to that observed in extremely metal-poor stars, whereas C abundances are not enhanced. This pattern is best explained as originating in metal-poor fast-rotating massive stars, which might point to a common property of the first stellar generations and even of the 'first stars'. PMID:21525928

  12. Media Capture and Wealth Concentration

    OpenAIRE

    Corneo, Giacomo

    2003-01-01

    While objective news coverage is vital to democracy, media bias can seriously distort collective decisions. This Paper develops a voting model where citizens are uncertain about the welfare effects induced by alternative policy options and derive information about those effects from the mass media. The media might, however, secretly collude with interest groups in order to influence the public opinion. In case of voting over the level of a productivity-enhancing public bad, it is shown that a...

  13. Neutron-capture elements in the s- and r-process-rich stars: Constraints on neutron-capture nucleosynthesis processes

    CERN Document Server

    Zhang, B; Zhou, G; Zhang, Bo; Ma, Kun; Zhou, Guide

    2006-01-01

    The chemical abundances of the very metal-poor double-enhanced stars are excellent information for setting new constraints on models of neutron-capture processes at low metallicity. These stars are known as s+r stars, since they show enhancements of both s-process and r-process elements. The observed abundance ratios for the double-enhanced stars can be explained by those of stars that were polluted by an AGB star and subsequently accreted very significant amounts of r-process material out of an AIC (accretion-induced collapse) or Type 1.5 supernova. In this paper we present for the first time an attempt to fit the elemental abundances observed in the s- and r-rich, very metal-poor stars using a parametric model and suggest a new concept of component coefficients to describe the contributions of the individual neutron-capture processes to double-enhanced stars. We find that the abundance ratios of these stars are best fitted by enrichments of s- and r-process material. The overlap factor in the AGB stars wher...

  14. The fast code

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, L.N.; Wilson, R.E. [Oregon State Univ., Dept. of Mechanical Engineering, Corvallis, OR (United States)

    1996-09-01

    The FAST Code which is capable of determining structural loads on a flexible, teetering, horizontal axis wind turbine is described and comparisons of calculated loads with test data are given at two wind speeds for the ESI-80. The FAST Code models a two-bladed HAWT with degrees of freedom for blade bending, teeter, drive train flexibility, yaw, and windwise and crosswind tower motion. The code allows blade dimensions, stiffnesses, and weights to differ and models tower shadow, wind shear, and turbulence. Additionally, dynamic stall is included as are delta-3 and an underslung rotor. Load comparisons are made with ESI-80 test data in the form of power spectral density, rainflow counting, occurrence histograms, and azimuth averaged bin plots. It is concluded that agreement between the FAST Code and test results is good. (au)

  15. A fast friend

    Institute of Scientific and Technical Information of China (English)

    高怡

    2010-01-01

    我们都知道fast food的意思是“快餐”。那fast friend能解释为“快速或速成的朋友”吗?也许你会说:“什么是速成朋友呀?It doesn’t make sense.”没错,交朋友怎么会有速成的呢?原来;fast还有一个意思是“忠实的、牢固的”,所以a fast friend的真正意思是“可靠、忠实的朋友”。

  16. Measurement of neutron capture on $^{48}$Ca at thermal and thermonuclear energies

    OpenAIRE

    Beer, H.; Coceva, C.; Sedyshev, P. V.; Popov, Yu. P.; Herndl, H.; Hofinger, R.; Mohr, P.; Oberhummer, H.

    1996-01-01

    At the Karlsruhe pulsed 3.75\\,MV Van de Graaff accelerator the thermonuclear $^{48}$Ca(n,$\\gamma$)$^{49}$Ca(8.72\\,min) cross section was measured by the fast cyclic activation technique via the 3084.5\\,keV $\\gamma$-ray line of the $^{49}$Ca-decay. Samples of CaCO$_3$ enriched in $^{48}$Ca by 77.87\\,\\% were irradiated between two gold foils which served as capture standards. The capture cross-section was measured at the neutron energies 25, 151, 176, and 218\\,keV, respectively. Additionally, t...

  17. Porous multi-component material for the capture and separation of species of interest

    Energy Technology Data Exchange (ETDEWEB)

    Addleman, Raymond S.; Chouyyok, Wilaiwan; Li, Xiaohong S.; Cinson, Anthony D.; Gerasimenko, Aleksandr A

    2016-06-21

    A method and porous multi-component material for the capture, separation or chemical reaction of a species of interest is disclosed. The porous multi-component material includes a substrate and a composite thin film. The composite thin film is formed by combining a porous polymer with a nanostructured material. The nanostructured material may include a surface chemistry for the capture of chemicals or particles. The composite thin film is coupled to the support or device surface. The method and material provides a simple, fast, and chemically and physically benign way to integrate nanostructured materials into devices while preserving their chemical activity.

  18. Nuclear reaction diagnostics of fast confined and escaping alpha particles

    International Nuclear Information System (INIS)

    The resonant radiative capture nuclear reactions D(α,γ)6Li, 6Li(α,γ) 19B and 7Li(α,γ)11B are examined as diagnostics of the energy distribution of confined fast alpha particles in tokamak plasmas. Count rates for realistic Q=1 DT plasma conditions are presented and compared to expected backgrounds. The design of and preliminary results from the prototype fusion gamma ray detector on TFTR are presented. The activation reactions are similarly examined as diagnostics of escaping fast alpha particles. Where possible, count rate estimates for Q=1 DT plasmas and proposed ignition devices are presented

  19. Opportunities for early Carbon Capture, Utilisation and Storage development in China

    Energy Technology Data Exchange (ETDEWEB)

    Jansen, D. [ECN Biomass and Energy Efficiency, Petten (Netherlands)

    2013-01-15

    The outline of the presentation shows the following elements: China CCUS (Carbon Capture, Utilisation and Storage) policy, strategy and development status; International developments in CCUS; High-purity CO2 sources and potential EOR (Enhanced Oil Recovery) locations in China; Capture routes: (a) Separation technologies/processes, (b) CO2 purity specifications, compression and after treatment, (c) CO2 transportation options, (d) Associated Cost; Potential cost-effective full-chain CCUS projects in Shaanxi; Barriers to CCUS development in Shaanxi; and Conclusions.

  20. Fast neutron dosimetry

    International Nuclear Information System (INIS)

    Research concentrated on three major areas during the last twelve months: (1) investigations of energy fluence and absorbed dose measurements using crystalline and hot pressed TLD materials exposes to ultrasoft beams of photons, (2) fast neutron kerma factor measurements for several important elements as well as NE-213 scintillation material response function determinations at the intense ''white'' source available at the WNR facility at LAMPF, and (3) kerma factor ratio determinations for carbon and oxygen to A-150 tissue equivalent plastic at the clinical fast neutron radiation facility at Harper Hospital, Detroit, MI. Progress summary reports of these efforts are given in this report

  1. Fast food in Tbilisi

    OpenAIRE

    Ulrica Soderlind

    2014-01-01

    This article deals with the fast food establishments that can be found in Georgia's capital Tbilisi as of today. The article is divided into two sections, first interviews with the managers or the owners of the establishments and then we hear the voices of the costumers by a questionnaire that was left for the costumers to answer while they were visiting the establishments. The article and study should be seen as a first academic attempt to map out the fast food sphere in Tbilisi that is quit...

  2. Commercialization of fast reactors

    International Nuclear Information System (INIS)

    Comparative analysis has been performed of capital and fuel cycle costs for fast BN-type and pressurized light water VVER-type reactors. As a result of materials demand and components costs comparison of NPPs with VVER-1000 and BN-600 reactors, respectively, conclusion was made, that under equal conditions of the comparison, NPP with fast reactor had surpassed the specific capital cost of NPP with VVER by about 30 - 40 %. Ways were determined for further decrease of this difference, as well as for the fuel cycle cost reduction, because at present it is higher than that of VVER-type reactors. (author)

  3. ATLAS fast physics monitoring

    Indian Academy of Sciences (India)

    Karsten Köneke; on behalf of the ATLAS Collaboration

    2012-11-01

    The ATLAS experiment at the Large Hadron Collider is recording data from proton–proton collisions at a centre-of-mass energy of 7 TeV since the spring of 2010. The integrated luminosity has grown nearly exponentially since then and continues to rise fast. The ATLAS Collaboration has set up a framework to automatically process the rapidly growing dataset and produce performance and physics plots for the most interesting analyses. The system is designed to give fast feedback. The histograms are produced within hours of data reconstruction (2–3 days after data taking). Hints of potentially interesting physics signals obtained this way are followed up by physics groups.

  4. Moms og fast ejendom

    DEFF Research Database (Denmark)

    Edlund, Hans Henrik

    1999-01-01

    I artiklen gives et overblik over, hvorledes fast ejendom behandles momsmæssigt. Derfor findes en kort skitsering af reglerne for moms på byggearbejder, afgrænsningen mellem momspligtig og momsfri udlejning, muligheden for frivillig registrering af udlejning samt opgørelse af reguleringsforpligte......I artiklen gives et overblik over, hvorledes fast ejendom behandles momsmæssigt. Derfor findes en kort skitsering af reglerne for moms på byggearbejder, afgrænsningen mellem momspligtig og momsfri udlejning, muligheden for frivillig registrering af udlejning samt opgørelse af...

  5. SERS detection of indirect viral DNA capture using colloidal gold and methylene blue as a Raman label

    Science.gov (United States)

    An indirect capture model assay using colloidal Au nanoparticles is demonstrated for surface enhanced Raman scattering (SERS) spectroscopy detection of DNA. The sequence targeted for capture is derived from the West Nile Virus (WNV) RNA genome and was selected on the basis of exhibiting minimal seco...

  6. Techno-Economic Study of Adsorption Processes for Pre-Combustion Carbon Capture at a Biomass CHP Plant

    OpenAIRE

    Oreggioni, Gabriel David; Friedrich, Daniel; Brandani, Stefano; Ahn, Hyungwoong

    2014-01-01

    An exemplary 10 MWth biomass CHP plant with a FICFB (Fast Internally Circulating Fluidised Bed) gasifier and Jenbacher type 6 gas engine was simulated to estimate the power and thermal outputs. The biomass-fuelled CHP plant was modified for carbon capture using either adsorption or amine process. It was found that a two-stage, two-bed PVSA (Pressure Vacuum Swing Adsorption) unit applied to syngas stream for pre-combustion capture spent less specific energy per captured CO2 than a conventional...

  7. Enhancement of the computational efficiency of the near-to-far field mapping in the finite-difference method and ray-by-ray method with the fast multi-pole plane wave expansion approach

    Science.gov (United States)

    Tang, Guanglin; Yang, Ping; Sun, Bingqiang; Panetta, R. Lee; Kattawar, George W.

    2016-06-01

    The finite-difference time-domain (FDTD) and ray-by-ray (RBR) methods are techniques used to calculate the optical properties of nonspherical particles for small-to-moderate and large size parameters, respectively. The former is a rigorous method, and the latter is an approximate geometric-physical optics-hybrid method that takes advantage of both high efficiency of the geometric optics approach and high accuracy of the physical optics approach. In these two methods, the far field is calculated by mapping the near field to the far field with consideration of the phase interference. The mapping computation is more time-consuming than the near-field simulation when multiple scattering directions are involved, particularly in the case of the RBR implementation. To overcome the difficulty, in this study the fast multi-pole method is applied to both FDTD and RBR towards accelerating the far-field calculation, without degrading the accuracy of the simulation results.

  8. Fast-track surgery in India.

    Science.gov (United States)

    Nanavati, Aditya J; Nagral, Sanjay; Prabhakar, Subramaniam

    2014-01-01

    Fast-track surgery or 'enhanced recovery after surgery' or 'multimodal rehabilitation after surgery' is a form of protocol-based perioperative care programme. It is an amalgamation of evidence-based practices that have been proven to improve patient outcome independently and exert a synergistic effect when applied together. The philosophy is to treat the patient's pathology with minimal disturbance to the physiology. Several surgical subspecialties have now adopted such protocols with good results. The role of fast-track surgery in colorectal procedures has been well demonstrated. Its application to other major abdominal surgical procedures is not as well defined but there are encouraging results in the few studies conducted. There has been resistance to several aspects of this programme among gastrointestinal and general surgeons. There is little data from India in the available literature on the application of fast-tracking in gastrointestinal surgery. In a country such as India the existing healthcare structure stands to gain the most by widespread adoption of fast-track methods. Early discharge, early ambulation, earlier return to work and increased hospital efficiency are some of the benefits. The cost gains derived from this programme stand to benefit the patient, doctor and government as well. The practice and implementation of fast-track surgery involves a multidisciplinary team approach. It requires policy formation at an institutional level and interdepartmental coordination. More research is required in areas like implementation of such protocols across India to derive the maximum benefit from them. PMID:25471759

  9. Electron capture to the continuum

    International Nuclear Information System (INIS)

    The second order Oppenheimer-Brinkman-Kramers approximation is used to derive simple analytical formulae, evaluated to the lowest order in the fine-structure constant α in the numerator, for the differential cross section for electron capture to the continuum (ECC) by incident bare ions having velocity ν from target hydrogenic atomic systems. Relativistic as well as non-relativistic forms are derived. Comparison of the theory with the experimental data of Dahl and Andersen et al for H+, He2+ + He collisions is fairly satisfactory for energies >50 keV amu-1. However, although the velocity dependence obtained by Andersen et al is ν-11.3±0.2 in the range of impact energies 1-2.6 MeV amu-1, this does not imply that the asymptotic ν-11 velocity dependence given by the non-relativistic second-order OBK cross section is almost attained. It is shown that this cannot happen until an energy >500 MeV amu-1 is reached where allowance for relativity produces a considerable change in the energy fall off. A modification of the second-order OBK approximation may be expanded to first order in the atomic number ΖP of the projectile ion to get simple formulae for the yield of continuum electrons and the cusp asymmetry factor β. The agreement with the data of Andersen et al for β is fair at impact energies >0.5 MeV amu-1P-1 but the situation is unclear at energies -1 ΖP-1 where the data of different experimenters doe not agree with each other and CDW calculations produce low values of β. (author)

  10. High spatial resolution fast-neutron imaging detectors for Pulsed Fast-Neutron Transmission Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Mor, I; Vartsky, D; Bar, D; Feldman, G; Goldberg, M B; Katz, D; Sayag, E; Shmueli, I; Cohen, Y; Tal, A; Vagish, Z [Soreq NRC, 81800 Yavne (Israel); Bromberger, B; Dangendorf, V; Mugai, D; Tittelmeier, K; Weierganz, M [Physikalisch-Technische Bundesanstalt (PTB), 38116 Braunschweig (Germany)], E-mail: ilmor@soreq.gov.il

    2009-05-15

    Two generations of a novel detector for high-resolution transmission imaging and spectrometry of fast-neutrons are presented. These devices are based on a hydrogenous fiber scintillator screen and single- or multiple-gated intensified camera systems (ICCD). This detector is designed for energy-selective neutron radiography with nanosecond-pulsed broad-energy (1-10 MeV) neutron beams. Utilizing the Time-of-Flight (TOF) method, such a detector is capable of simultaneously capturing several images, each at a different neutron energy (TOF). In addition, a gamma-ray image can also be simultaneously registered, allowing combined neutron/gamma inspection of objects. This permits combining the sensitivity of the fast-neutron resonance method to low-Z elements with that of gamma radiography to high-Z materials.

  11. High Spatial Resolution Fast-Neutron Imaging Detectors for Pulsed Fast-Neutron Transmission Spectroscopy

    CERN Document Server

    Mor, I; Bar, D; Feldman, G; Goldberg, M B; Katz, D; Sayag, E; Shmueli, I; Cohen, Y; Tal, A; Vagish, Z; Bromberger, B; Dangendorf, V; Mugai, D; Tittelmeier, K; Weierganz, M

    2009-01-01

    Two generations of a novel detector for high-resolution transmission imaging and spectrometry of fast-neutrons are presented. These devices are based on a hydrogenous fiber scintillator screen and single- or multiple-gated intensified camera systems (ICCD). This detector is designed for energy-selective neutron radiography with nanosecond-pulsed broad-energy (1 - 10 MeV) neutron beams. Utilizing the Time-of-Flight (TOF) method, such a detector is capable of simultaneously capturing several images, each at a different neutron energy (TOF). In addition, a gamma-ray image can also be simultaneously registered, allowing combined neutron/gamma inspection of objects. This permits combining the sensitivity of the fast-neutron resonance method to low-Z elements with that of gamma radiography to high-Z materials.

  12. Experience machines : Capturing and retrieving personal content

    NARCIS (Netherlands)

    Werkhoven, P.

    2005-01-01

    Fundamental to human existence is the ability to capture, memorise and retrieve personal experiences and to share them with others. Can systems help us to capture and retrieve experiences? After motors have supplemented our muscles and sensors have supplemented our senses, emerging computer systems

  13. Screen captures to support switching attention

    NARCIS (Netherlands)

    Gellevij, Mark; Meij, van der Hans

    2002-01-01

    The study set out to validate the supportive role of screen captures for switching attention. Forty-two participants learned how to work with Microsoft Excel with a paper manual. There were three types of manuals: a textual manual, a visual manual with full-screen captures, and a visual manual with

  14. kev neutron capture in zirconium-91

    International Nuclear Information System (INIS)

    The neutron capture cross section of 91Zr has been measured with high resolution (ΔE/E approximately 0.2 per cent) between 3 and 30 keV. Values of the gGAMMAsub(n)GAMMAsub(γ) for 119 resonances in this energy range have been obtained. The average capture cross section is consistent with values of = = 200. (author)

  15. Delirium in fast-track colonic surgery

    DEFF Research Database (Denmark)

    Kurbegovic, Sorel; Andersen, Jens; Krenk, Lene; Kehlet, Henrik

    2015-01-01

    BACKGROUND: Postoperative delirium (PD) is a common but serious problem after major surgery with a multifactorial pathogenesis including age, pain, opioid use, sleep disturbances and the surgical stress response. These factors have been minimised by the "fast-track methodology" previously...... demonstrated to enhance recovery and reduce morbidity. METHODS: Clinical symptoms of PD were routinely collected three times daily from preoperatively until discharge in a well-defined enhanced recovery program after colonic surgery in 247 consecutive patients. RESULTS: Total median length of hospital stay was...

  16. Immobilization Techniques and Integrated Signal Enhancement for POC Nanocolor Microfluidic Devices

    Directory of Open Access Journals (Sweden)

    Marlies Schlauf

    2015-01-01

    Full Text Available Resonance enhanced absorption (REA nanocolor microfluidic devices are new promising bioassay platforms, which employ nanoparticle- (NP- protein conjugates for the immunodetection of medically relevant markers in biologic samples such as blood, urine, and saliva. The core component of a REA test device is a PET chip coated with aluminum and SiO2 thin layers, onto which biorecognitive molecules are immobilized. Upon addition of a sample containing the analyte of interest, a NP-protein-analyte complex is formed in the test device that is captured on the REA chip, for example, via streptavidin-biotin interaction. Thereby, a colored symbol is generated, which allows optical readout. Silver enhancement of the bound nanoparticles may be used to increase the sensitivity of the assay. Herein, we demonstrate that adsorptive immobilization via a cationic polymeric interlayer is a competitive and fast technique for the binding of the capture protein streptavidin onto planar SiO2 surfaces such as REA biochips. Moreover, we report the development of a silver enhancement technology that operates even in the presence of high chloride concentrations as may be encountered in biologic samples. The silver enhancement reagents may be integrated into the microfluidic assay platform to be released upon sample addition. Hereby, a highly sensitive one-step assay can be realized.

  17. Capture of Planetesimals into a Circumterrestrial Swarm

    Science.gov (United States)

    Weidenschilling, S. J.

    1985-01-01

    The lunar origin model considered in this report involves processing of protolunar material through a circumterrestrial swarm of particles. Once such a swarm has formed, it can gain mass by capturing infalling planetesimals and ejecta from giant impacts on the Earth, although the angular momentum supply from these sources remains a problem. The first stage of formation of a geocentric swarm by capture of planetesimals from initially heliocentric orbits is examined. The only plausible capture mechanism that is not dependent on very low approach velocities is the mutual collision of planetesimals passing within Earth's sphere of influence. The dissipation of energy in inelastic collisions or accretion events changes the value of the Jacobi parameter, allowing capture into bound geocentric orbits. This capture scenario was tested directly by many body numerical integration of planetesimal orbits in near Earth space.

  18. CO2 Capture by Cement Raw Meal

    DEFF Research Database (Denmark)

    Pathi, Sharat Kumar; Lin, Weigang; Illerup, Jytte Boll;

    2013-01-01

    The cement industry is one of the major sources of CO2 emissions and is likely to contribute to further increases in the near future. The carbonate looping process has the potential to capture CO2 emissions from the cement industry, in which raw meal for cement production could be used as the...... sorbent. Cyclic experiments were carried out in a TGA apparatus using industrial cement raw meal and synthetic raw meal as sorbents, with limestone as the reference. The results show that the CO2 capture capacities of the cement raw meal and the synthetic raw meal are comparable to those of pure limestone....... The CO2 capture capacity of limestone in the raw meal is lower than for pure limestone. The difference in the CO2 capture capacity decreases with an increase in cycle number. The calcination conditions and composition are major factors that influence the CO2 capture capacity of limestone. At 850 °C in...

  19. Integral Fast Reactor Program

    International Nuclear Information System (INIS)

    This report summarizes highlights of the technical progress made in the Integral Fast Reactor (IFR) Program in FY 1992. Technical accomplishments are presented in the following areas of the IFR technology development activities: (1) metal fuel performance, (2) pyroprocess development, (3) safety experiments and analyses, (4) core design development, (5) fuel cycle demonstration, and (6) LMR technology R ampersand D

  20. Fast Passenger Tracks Network

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    China’s fast passenger tracks network consists of four parts:express rail- way with speeds between 300km/h and 350 kin/h,passenger rail lines with speeds between 200 km/h and 250 km/h,intercity high-speed railways that run

  1. Fast reactor programme

    International Nuclear Information System (INIS)

    This progress report summarises the fast reactor research carried out at the Netherlands Energy Research Centre during the year 1981. The neutron and fission product cross sections of various isotopes have been evaluated. In the fuel performance programme, some preliminary results are given and irradiation facilities described. Creep experiments on various stainless steel components are reported

  2. China experimental fast reactor

    International Nuclear Information System (INIS)

    The Chinese experimental fast reactor (CEFR) is a pool-type sodium-cooled fast reactor whose short term purposes are: -) the validation of computer codes, -) the check of the relevance of standards, and -) the gathering of experimental data on fast reactors. On the long term the expectations will focus on: -) gaining experience in fast reactor operations, -) the testing of nuclear fuels and materials, and -) the study of sodium compounds. The main technical features of CEFR are: -) thermal power output: 65 MW (electrical power output: 20 MW), -) size of the core: height: 45 cm, diameter: 60 cm, -) maximal linear output: 430 W/cm, -) neutron flux: 3.7*1015 n/cm2/s, -) input/output sodium temperature: 360 / 530 Celsius degrees, -) 2 loops for the primary system and 2 loops for the secondary system. The temperature coefficient and the power coefficient are settled to stay negative for any change in the values of the core parameters. The installation of the reactor vessel will be completed by mid 2007. The first criticality of CEFR is expected during the first semester of 2010. (A.C.)

  3. Fast nastic motion of plants and bio-inspired structures

    OpenAIRE

    Guo, Qiaohang; Dai, Eric; Han, Xiaomin; Xie, Stephen; Chao, Eric; Chen, Zi

    2015-01-01

    The capability to sense and respond to external mechanical stimuli at various timescales is essential to many physiological aspects in plants, including self-protection, intake of nutrients, and reproduction. Remarkably, some plants have evolved the ability to react to mechanical stimuli within a few seconds despite a lack of muscles and nerves. The fast movements of plants in response to mechanical stimuli have long captured the curiosity of scientists and engineers, but the mechanisms behin...

  4. Fast nastic motion of plants and bioinspired structures

    OpenAIRE

    Guo, Q.; Dai, E.; Han, X.; Xie, S.; Chao, E; Chen, Z.

    2015-01-01

    The capability to sense and respond to external mechanical stimuli at various timescales is essential to many physiological aspects in plants, including self-protection, intake of nutrients and reproduction. Remarkably, some plants have evolved the ability to react to mechanical stimuli within a few seconds despite a lack of muscles and nerves. The fast movements of plants in response to mechanical stimuli have long captured the curiosity of scientists and engineers, but the mechanisms behind...

  5. Dynamics of fast charged particle beam rotation in bended crystals

    International Nuclear Information System (INIS)

    Dynamics of fast charged particle beam rotation in a bended monocrystal is considered. Face and volume mechanisms of capture in channels are taken into account simultaneously in the model presented. Functions of distribution in transverse energies (φ) of channeled and dechanneled particles are obtained. Charge-energy ''scale invariance'' in ion channeling with charge Z in a bended crystal determined by scale parameter W=pv/Z (p and v are pulse and velocity local to transverse planes) follows from the model presented

  6. Real-time dosimetry for boron-neutron capture therapy

    International Nuclear Information System (INIS)

    Epithermal/thermal boron neutron-capture therapy (BNCT) is promising treatment method for malignant tumors. Because the doses and dose rates for medical therapeutic radiation are very close to the normal tissue tolerance, small errors in radiation delivery can result in harmful overdoses. A substantial need exists for a device that will monitor, in real time, the radiation dose being delivered to a patient. Pacific Northwest Laboratory (PNL) has developed a scintillating glass optical fiber that is sensitive to thermal neutrons. The small size of the fibers offers the possibility of in vivo dose monitoring at several points within the radiation field. The count rate of such detectors can approach 10 MHz because the lifetime of the cerium activator is fast. Fluxes typical of those in BNCT (i.e., 109 n/cm2/sec) may be measured because of this potentially high count rate and the small diameter of the fiber

  7. Levels in 237U studied by resonant neutron capture

    International Nuclear Information System (INIS)

    Primary and secondary γ rays in 237U from resonant neutron capture in 236U have been measured with the fast chopper facility, the neutron monochromator, and 2- and 24-keV neutron beam filters. A level scheme was constructed including 27 levels with spin and parity assignments. Rotational band members of the Nilsson configurations [631arrow-down], [622up-arrow], [624arrow-down], [631up-arrow], [633arrow-down], and [501arrow-down] and of the vibrational bands ][622up-arrow] - 2+] and ][631arrow-down] + 0+] were identified. There are more levels below 800 keV, in particular, K = 1/2- bands, than expected from comparison with 235U and 239U. The neutron binding energy in 237U was determined to be 5125.9 +- 0.5 keV

  8. An overview of the theory of Microeconomics (consumer behaviour and market structures) in fast food marketing

    OpenAIRE

    Emmanuel Selase Asamoah; Miloslava Chovancová

    2011-01-01

    This paper provides an overview of the application of microeconomic theories in fast food marketing. The aim is to bring out the interrelationship between marketing and microeconomics with respect to the fast food industry. The paper examines some conceptual and theoretical tools that will enhance the marketing practices of managers in the fast food industry. Hence, the marketing aspects of international fast food firms are analyzed within the framework of the concept of consumer behaviour an...

  9. Fast breeder reactor research

    International Nuclear Information System (INIS)

    Full text: The meeting was attended by 15 participants from seven countries and two international organizations. The Eighth Annual Meeting of the International Working Group on Fast Reactors (IWGFR) was attended by representatives from France, Fed. Rep. Germany, Italy, Japan, United Kingdom, Union of Soviet Socialist Republics and the United States of America - countries that have made significant progress in developing the technology and physics of sodium cooled fast reactors and have extensive national programmes in this field - as well as by representatives of the Commission of the European Communities and the IAEA. The design of fast-reactor power plants is a more difficult task than developing facilities with thermal reactors. Different reactor kinetics and dynamics, a hard neutron spectrum, larger integral doses of fuel and structural material irradiation, higher core temperatures, the use of an essentially novel coolant, and, as a result of all these factors, the additional reliability and safety requirements that are imposed on the planning and operation of sodium cooled fast reactors - all these factors pose problems that can be solved comprehensively only by countries with a high level of scientific and technical development. The exchange of experience between these countries and their combined efforts in solving the fundamental problems that arise in planning, constructing and operating fast reactors are promoting technical progress and reducing the relative expenditure required for various studies on developing and introducing commercial fast reactors. For this reason, the meeting concentrated on reviewing and discussing national fast reactor programmes. The situation with regard to planning, constructing and operating fast experimental and demonstration reactors in the countries concerned, the experience accumulated in operating them, the difficulties arising during operation and ways of over-coming them, the search for optimal designs for the power

  10. Towards gadolinium neutron capture therapy

    International Nuclear Information System (INIS)

    As glioblastoma multiforme has macroscopic areas with poor vascularisation, and thereby poor uptake of an NCT-agent, the long-range γ-rays from GdNCT might enhance dose deposition compared to BNCT and to conformal photon therapy. Multicellular spheroids from a human glioblastoma cell line (Gli-6) were irradiated with conventional X-rays, with neutrons only (from the NRG Argonaut Reactor, LFR), and with neutrons (from the LFR) + 157Gd-DTPA (240 ppm 157Gd). Preliminary results demonstrate that after neutron irradiation in the presence of 157Gd, the spheroids showed growth arrest. By 3D treatment planning calculations on MRI's from patients with brain tumours, dose volume histograms (DVH) for GdNCT were compared to DVH for conventional conformal radiotherapy. The calculations indicate that GdNCT on patients with large, deep-seated tumours yields better tumour/brain dose distribution than conformal radiotherapy. (author)

  11. Capturing triplet emission in white organic light emitting devices

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Jai [Faculty of EHSE, School of Engineering and IT, B-purple-12, Charles Darwin University, Darwin, NT 0909 (Australia)

    2011-08-15

    The state-of-the art in the white organic light emitting devices (WOLEDs) is reviewed for further developments with a view to enhance the capture of triplet emission. In particular, applying the new exciton-spin-orbit-photon interaction operator as a perturbation, rates of spontaneous emission are calculated in a few phosphorescent materials and compared with experimental results. For iridium based phosphorescent materials the rates agree quite well with the experimental results. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  12. Dynamic MR hepatocholangiography with the SIP Fast GRE (saturation inversion projection fast gradient echo) method

    International Nuclear Information System (INIS)

    The purpose of this study was to assess the utility of dynamic MR hepatocholangiography with the Gd-EOB-DTPA enhanced SIP Fast GRE sequence in the hepatobiliary system. The SIP Fast GRE sequence was used for sequential imaging of the hepatobiliary system with a frame rate of 3 sec in a 256 x 192 matrix. Dynamic sequential acquisition was performed for 51 min before and after the injection of 30μmol/kg of Gd-EOB-DTPA in a rabbit. Dynamic images of the hepatobiliary system were obtained in the rabbit study. Dynamic MR hepatocholangiography provides better functional information than conventional MR cholangiography. (author)

  13. Capture of irregular satellites at Jupiter

    International Nuclear Information System (INIS)

    The irregular satellites of outer planets are thought to have been captured from heliocentric orbits. The exact nature of the capture process, however, remains uncertain. We examine the possibility that irregular satellites were captured from the planetesimal disk during the early solar system instability when encounters between the outer planets occurred. Nesvorný et al. already showed that the irregular satellites of Saturn, Uranus, and Neptune were plausibly captured during planetary encounters. Here we find that the current instability models present favorable conditions for capture of irregular satellites at Jupiter as well, mainly because Jupiter undergoes a phase of close encounters with an ice giant. We show that the orbital distribution of bodies captured during planetary encounters provides a good match to the observed distribution of irregular satellites at Jupiter. The capture efficiency for each particle in the original transplanetary disk is found to be (1.3-3.6) × 10–8. This is roughly enough to explain the observed population of jovian irregular moons. We also confirm Nesvorný et al.'s results for the irregular satellites of Saturn, Uranus, and Neptune.

  14. Capture of irregular satellites at Jupiter

    Energy Technology Data Exchange (ETDEWEB)

    Nesvorný, David; Vokrouhlický, David; Deienno, Rogerio [Department of Space Studies, Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302 (United States)

    2014-03-20

    The irregular satellites of outer planets are thought to have been captured from heliocentric orbits. The exact nature of the capture process, however, remains uncertain. We examine the possibility that irregular satellites were captured from the planetesimal disk during the early solar system instability when encounters between the outer planets occurred. Nesvorný et al. already showed that the irregular satellites of Saturn, Uranus, and Neptune were plausibly captured during planetary encounters. Here we find that the current instability models present favorable conditions for capture of irregular satellites at Jupiter as well, mainly because Jupiter undergoes a phase of close encounters with an ice giant. We show that the orbital distribution of bodies captured during planetary encounters provides a good match to the observed distribution of irregular satellites at Jupiter. The capture efficiency for each particle in the original transplanetary disk is found to be (1.3-3.6) × 10{sup –8}. This is roughly enough to explain the observed population of jovian irregular moons. We also confirm Nesvorný et al.'s results for the irregular satellites of Saturn, Uranus, and Neptune.

  15. Impact of Thorium Capture Cross Section Uncertainty on the Thorium Utilized ADS Reactivity Calculation

    OpenAIRE

    Thanh Mai Vu; Takanori Kitada

    2014-01-01

    Recently, the researches on fast neutron spectrum system utilized thorium fuel are widely conducted. However, the recent thorium cross section libraries are limited compared to uranium cross section libraries. The impact of thorium cross section uncertainty on thorium fuel utilized accelerator driven system (ADS) reactivity calculation is estimated in this study. The uncertainty of the keff caused by 232Th capture cross section of JENDL-4.0 is about 1.3%. The uncertainty of JENDL-4.0 is neede...

  16. The Processing of Image Data Collected by Light UAV Systems for GIS Data Capture and Updating

    OpenAIRE

    N. Yastikli; I. Bagci; C. Beser

    2013-01-01

    The collection and updating of 3D data is the one of the important steps for GIS applications which require fast and efficient data collection methods. The photogrammetry has been used for many years as a data collection method for GIS application in larger areas. The Unmanned Aerial Vehicles (UAV) Systems gained increasing attraction in geosciences for cost effective data capture and updating at high spatial and temporal resolution during the last years. These autonomously flying UA...

  17. Minimizing capture-related stress on white-tailed deer with a capture collar

    Science.gov (United States)

    DelGiudice, G.D.; Kunkel, K.E.; Mech, L.D.; Seal, U.S.

    1990-01-01

    We compared the effect of 3 capture methods for white-tailed deer (Odocoileus virginianus) on blood indicators of acute excitement and stress from 1 February to 20 April 1989. Eleven adult females were captured by Clover trap or cannon net between 1 February and 9 April 1989 in northeastern Minnesota [USA]. These deer were fitted with radio-controlled capture collars, and 9 deer were recaptured 7-33 days later. Trapping method affected serum cortisol (P capture-collared deer (0.54 .+-. 0.07 [SE] .mu.g/dL) compared to Clover-trapped (4.37 .+-. 0.69 .mu.g/dL) and cannon-netted (3.88 .+-. 0.82 .mu.g/dL) deer. Capture-collared deer were minimally stressed compared to deer captured by traditional methods. Use of the capture collar should permit more accurate interpretation of blood profiles of deer for assessement of condition and general health.

  18. Hydrodynamics of jumping for prey capture in Archer fish

    Science.gov (United States)

    Techet, A. H.; Shih, A. M.

    2010-11-01

    The prey capture behavior by jumping Archer fish (Toxotes microlepisis) was investigated using high speed imaging and particle imaging velocimetry (PIV). Archer fish are renowned for their ability to spit jets of water at insects and also to jump out of the water to capture their prey. Our investigations reveal that the fish typically fail to reach their prey by jumping when the bait is placed at a height above 3.5 body lengths. After jumping and failing, the fish do not typically jump again, only spit. For our experiments bait was placed between 0.5 and 3.5 body lengths (BL) above the free surface, within reach of jumping, and thus the fish rarely spit unless they missed first by jumping. It is observed that the fish typically position their bodies under the bait with a slight angle, hover momentarily, snap in their pectoral fins, and then flap their tail in an "S-start"-type maneuver with a fixed number of cycles, which increases as a function of bait height. High speed imaging, including time-resolved PIV, was used to capture the kinematics of the jumping behavior and compare the fluid impulse generated during the fast start, jump maneuver with the total change in momentum of the fish body. Maximum acceleration was observed in the early stages of the jump maneuver and was often on the order of 5 to 15 times gravity. Correlations between the maximum energy, power in, number of tail beats, jump height and overall jumping kinematics will be discussed.

  19. Understanding Motion Capture for Computer Animation

    CERN Document Server

    Menache, Alberto

    2010-01-01

    The power of today's motion capture technology has taken animated characters and special effects to amazing new levels of reality. And with the release of blockbusters like Avatar and Tin-Tin, audiences continually expect more from each new release. To live up to these expectations, film and game makers, particularly technical animators and directors, need to be at the forefront of motion capture technology. In this extensively updated edition of Understanding Motion Capture for Computer Animation and Video Games, an industry insider explains the latest research developments in digital design

  20. The carbon dioxide capture and geological storage

    International Nuclear Information System (INIS)

    This road-map proposes by the Group Total aims to inform the public on the carbon dioxide capture and geological storage. One possible means of climate change mitigation consists of storing the CO2 generated by the greenhouse gases emission in order to stabilize atmospheric concentrations. This sheet presents the CO2 capture from lage fossil-fueled combustion installations, the three capture techniques and the CO2 transport options, the geological storage of the CO2 and Total commitments in the domain. (A.L.B.)

  1. Screen captures to support switching attention

    OpenAIRE

    Gellevij, Mark; Meij, van der, T.

    2002-01-01

    The study set out to validate the supportive role of screen captures for switching attention. Forty-two participants learned how to work with Microsoft Excel with a paper manual. There were three types of manuals: a textual manual, a visual manual with full-screen captures, and a visual manual with a mixture of partial- and full-screen captures. The findings show that participants in all conditions looked up from the manual to the screen on about 97% of the cases in which such a switch was ca...

  2. Gravitational Capture of Asteroids by Gas Drag

    Directory of Open Access Journals (Sweden)

    E. Vieira Neto

    2009-01-01

    captured by the planet got its velocity reduced and could been trapped as an irregular satellite. It is well known that, depending on the time scale of the gas envelope, an asteroid will spiral and collide with the planet. So, we simulate the passage of the asteroid in the gas envelope with its density decreasing along the time. Using this approach, we found effective captures, and have a better understanding of the whole process. Finally, we conclude that the origin of the irregular satellites cannot be attributed to the gas drag capture mechanism alone.

  3. Carbon dioxide capture and geological storage

    OpenAIRE

    2013-01-01

    Sustainable Carbon dioxide Capture and Storage, or CCS, can be achieved using geological means, an approach that differs in many ways from CO2 capture and storage in vegetation. Firstly, it differs because this latter approach enables CO2 to be stored only temporarily – for less than one year in annual plants or for several centuries in tree phytomass. Secondly, CO2 capture is associated with bioconversion of the sun’s energy which is then stored in biochemical form in the phytomass. As the t...

  4. A Solenoid Capture System for Neutrino Production

    International Nuclear Information System (INIS)

    This paper describes the use of a high field solenoidal magnet to capture secondary pions from the production target. The captured pions subsequentially decay to produce the neutrino beam. A pion capture system using a high field solenoid magnet has been proposed for the muon collider. This technology would also be available for neutrino beam production. It will be shown that a high field solenoid would produce a larger flux of neutrinos with energy, Eν e, (bar ν)e flux contamination in the solenoid neutrino beam is only 0.15%

  5. CO2 Capture by Carbon Aerogel–Potassium Carbonate Nanocomposites

    Directory of Open Access Journals (Sweden)

    Guang Yang

    2016-01-01

    Full Text Available Recently, various composites for reducing CO2 emissions have been extensively studied. Because of their high sorption capacity and low cost, alkali metal carbonates are recognized as a potential candidate to capture CO2 from flue gas under moist conditions. However, undesirable effects and characteristics such as high regeneration temperatures or the formation of byproducts lead to high energy costs associated with the desorption process and impede the application of these materials. In this study, we focused on the regeneration temperature of carbon aerogel–potassium carbonate (CA–KC nanocomposites, where KC nanocrystals were formed in the mesopores of the CAs. We observed that the nanopore size of the original CA plays an important role in decreasing the regeneration temperature and in enhancing the CO2 capture capacity. In particular, 7CA–KC, which was prepared from a CA with 7 nm pores, exhibited excellent performance, reducing the desorption temperature to 380 K and exhibiting a high CO2 capture capacity of 13.0 mmol/g-K2CO3, which is higher than the theoretical value for K2CO3 under moist conditions.

  6. Fast radiographic systems

    International Nuclear Information System (INIS)

    Industrial radiography can be performed with shorter exposure times, when instead of X-ray film with lead intensifying screens the radiographic paper with fluorescent screen is used. With paper radiography one can obtain lower material, equipment, and labor costs, shorter exposure and processing times, and easier radiation protection. The speed of the radiographic inspection can also be increased by the use of fluorometallic intensifying screens together with a special brand of X-ray film. Before accepting either of the two fast radiographic systems one must be sure that they can produce radiographs of adequate image quality. Therefore an investigation was performed on that subject using ISO wire IQI's and ASTM penetrameters. The radiographic image quality was tested for aluminium and steel up to 30 mm thick using various brands of radiographic paper and X-ray film with fluorometallic screens and comparing them with fast X-ray films with lead screens. Both systems give satisfactory results. (author)

  7. Fast reactor database

    International Nuclear Information System (INIS)

    This publication contains detailed data on liquid metal cooled fast reactors (LMFRs), specifically plant parameters and design details. Each LMFR power plant is characterized by about 400 parameters, by design data and by relevant materials. The report provides general and detailed design characteristics including structural materials, data on experimental, demonstration, prototype and commercial size LMFRs. The focus is on practical issues that are useful to engineers, scientists, managers and university students and professors. The report includes updated information contained in IAEA previous publications on LMFR plant parameters: IWGRF/51 (1985) and IWGFR/80 (1991) and reflects experience gained from two consultants meetings held in Vienna (1993,1994). This compilation of data was produced by members of the IAEA International Working Group on Fast Reactors (IWGFR)

  8. Note: A technique to capture and compose streak images of explosive events with unpredictable timing.

    Science.gov (United States)

    Parker, Gary R; Asay, Blaine W; Dickson, Peter M

    2010-01-01

    The authors describe a method to capture optical data and construct digitized streak images for analysis of high-speed phenomena with unpredictable timing by using a high-speed video camera and software routines. Advances in high-speed video camera technology have led to development of cameras with frame rates (1 x 10(6) frames per second) and spatial resolution (1280 x 800 pixels) suitable to capture fast phenomena, such as detonation in high explosives ( or = 1 s) are maintained in a rolling buffer in volatile memory allowing the entire frame sequence to be recorded pretrigger, thus obviating the need for precisely located diagnostic triggers. The method described was used to capture the progression of luminous reaction during the deflagration-to-detonation transition of the HMX-based (octahydro-1, 3, 5, 7-tetranitro-1, 3, 5, 7-tetrazocine) plastic bonded explosive (PBX) formulation during cookoff. PMID:20113140

  9. New measurement of $\\theta_{13}$ via neutron capture on hydrogen at Daya Bay

    CERN Document Server

    An, F P; Band, H R; Bishai, M; Blyth, S; Cao, D; Cao, G F; Cao, J; Cen, W R; Chan, Y L; Chang, J F; Chang, L C; Chang, Y; Chen, H S; Chen, Q Y; Chen, S M; Chen, Y X; Chen, Y; Cheng, J H; Cheng, J -H; Cheng, J; Cheng, Y P; Cheng, Z K; Cherwinka, J J; Chu, M C; Chukanov, A; Cummings, J P; de Arcos, J; Deng, Z Y; Ding, X F; Ding, Y Y; Diwan, M V; Dolgareva, M; Dove, J; Dwyer, D A; Edwards, W R; Gill, R; Gonchar, M; Gong, G H; Gong, H; Grassi, M; Gu, W Q; Guan, M Y; Guo, L; Guo, R P; Guo, X H; Guo, Z; Hackenburg, R W; Han, R; Hans, S; He, M; Heeger, K M; Heng, Y K; Higuera, A; Hor, Y K; Hsiung, Y B; Hu, B Z; Hu, T; Hu, W; Huang, E C; Huang, H X; Huang, X T; Huber, P; Huo, W; Hussain, G; Jaffe, D E; Jaffke, P; Jen, K L; Jetter, S; Ji, X P; Ji, X L; Jiao, J B; Johnson, R A; Joshi, J; Kang, L; Kettell, S H; Kohn, S; Kramer, M; Kwan, K K; Kwok, M W; Kwok, T; Langford, T J; Lau, K; Lebanowski, L; Lee, J; Lee, J H C; Lei, R T; Leitner, R; Leung, J K C; Li, C; Li, D J; Li, F; Li, G S; Li, Q J; Li, S; Li, S C; Li, W D; Li, X N; Li, Y F; Li, Z B; Liang, H; Lin, C J; Lin, G L; Lin, S; Lin, S K; Lin, Y -C; Ling, J J; Link, J M; Littenberg, L; Littlejohn, B R; Liu, D W; Liu, J J; Liu, J L; Liu, J C; Loh, C W; Lu, C; Lu, H Q; Lu, J S; Luk, K B; Lv, Z; Ma, Q M; Ma, X Y; Ma, X B; Ma, Y Q; Malyshkin, Y; Caicedo, D A Martinez; McDonald, K T; McKeown, R D; Mitchell, I; Mooney, M; Nakajima, Y; Napolitano, J; Naumov, D; Naumova, E; Ngai, H Y; Ning, Z; Ochoa-Ricoux, J P; Olshevskiy, A; Pan, H -R; Park, J; Patton, S; Pec, V; Peng, J C; Pinsky, L; Pun, C S J; Qi, F Z; Qi, M; Qian, X; Raper, N; Ren, J; Rosero, R; Roskovec, B; Ruan, X C; Steiner, H; Sun, G X; Sun, J L; Tang, W; Taychenachev, D; Konstantin, T; Tsang, K V; Tull, C E; Viaux, N; Viren, B; Vorobel, V; Wang, C H; Wang, M; Wang, N Y; Wang, R G; Wang, W; Wang, W W; Wang, X; Wang, Y F; Wang, Z; Wang, Z M; Wei, H Y; Wen, L J; Whisnant, K; White, C G; Whitehead, L; Wise, T; Wong, H L H; Wong, S C F; Worcester, E; Wu, C -H; Wu, Q; Xia, D M; Xia, J K; Xing, Z Z; Xu, J Y; Xu, J L; Xu, J; Xu, Y; Xue, T; Yan, J; Yang, C G; Yang, H; Yang, L; Yang, M S; Yang, M T; Ye, M; Ye, Z; Yeh, M; Young, B L; Yu, G Y; Yu, Z Y; Zhan, L; Zhang, C; Zhang, H H; Zhang, J W; Zhang, Q M; Zhang, X T; Zhang, Y M; Zhang, Y X; Zhang, Z J; Zhang, Z Y; Zhang, Z P; Zhao, J; Zhao, Q W; Zhao, Y F; Zhao, Y B; Zhong, W L; Zhou, L; Zhou, N; Zhuang, H L; Zou, J H

    2016-01-01

    This article reports an improved independent measurement of neutrino mixing angle $\\theta_{13}$ at the Daya Bay Reactor Neutrino Experiment. Electron antineutrinos were identified by inverse $\\beta$-decays with the emitted neutron captured by hydrogen, yielding a data-set with principally distinct uncertainties from that with neutrons captured by gadolinium. With the final two of eight antineutrino detectors installed, this study used 621 days of data including the previously reported 217-day data set with six detectors. The dominant statistical uncertainty was reduced by 49%. Intensive studies of the cosmogenic muon-induced $^9$Li and fast neutron backgrounds and the neutron-capture energy selection efficiency, resulted in a reduction of the systematic uncertainty by 26%. The deficit in the detected number of antineutrinos at the far detectors relative to the expected number based on the near detectors yielded $\\sin^22\\theta_{13} = 0.071 \\pm 0.011$ in the three-neutrino-oscillation framework. The combination...

  10. Bright flares in supergiant fast X-ray transients

    Science.gov (United States)

    Shakura, N.; Postnov, K.; Sidoli, L.; Paizis, A.

    2014-08-01

    At steady low-luminosity states, supergiant fast X-ray transients (SFXTs) can be at the stage of quasi-spherical settling accretion on to slowly rotating magnetized neutron stars from the OB-companion winds. At this stage, a hot quasi-static shell is formed above the magnetosphere, the plasma entry rate into magnetosphere is controlled by (inefficient) radiative plasma cooling, and the accretion rate on to the neutron star is suppressed by a factor of ˜30 relative to the Bondi-Hoyle-Littleton value. Changes in the local wind velocity and density due to, e.g. clumps, can only slightly increase the mass accretion rate (a factor of ˜10) bringing the system into the Compton-cooling-dominated regime and led to the production of moderately bright flares (Lx ≲ 1036 erg s-1). To interpret the brightest flares (Lx > 1036 erg s-1) displayed by the SFXTs within the quasi-spherical settling accretion regimes, we propose that a larger increase in the mass accretion rate can be produced by sporadic capture of magnetized stellar wind plasma. At sufficiently low accretion rates, magnetic reconnection can enhance the magnetospheric plasma entry rate, resulting in copious production of X-ray photons, strong Compton cooling and ultimately in unstable accretion of the entire shell. A bright flare develops on the free-fall time-scale in the shell, and the typical energy released in an SFXT bright flare corresponds to the mass of the shell. This view is consistent with the energy released in SFXT bright flares (˜1038-1040 erg), their typical dynamic range (˜100) and with the observed dependence of these characteristics on the average unflaring X-ray luminosity of SFXTs. Thus, the flaring behaviour of SFXTs, as opposed to steady HMXBs, may be primarily related to their low X-ray luminosity allowing sporadic magnetic reconnection to occur during magnetized plasma entry into the magnetosphere.

  11. Cross Sections for High-Energy Gamma Transitions from MeV Neutron Capture in 206Pb

    International Nuclear Information System (INIS)

    Gamma-ray spectra from neutron capture in Pb (radiogenic lead) in the energy range 1.5 to 8.5 MeV were recorded using time-of-flight techniques. The spectrometer was a Nal (Tl) crystal, 20.8 cm long and 22.6 cm in diameter. The spectra are dominated by gamma transitions to levels with large single-particle strength, in agreement with predictions of semi-direct capture theories. The theories predict enhancements of the direct capture cross section by a factor of 10 - 15 in the region of the giant dipole resonance. The observed enhancement is about 50

  12. The radiobiological principles of boron neutron capture therapy: A critical review

    International Nuclear Information System (INIS)

    The radiobiology of the dose components in a BNCT exposure is examined. The effect of exposure time in determining the biological effectiveness of γ-rays, due to the repair of sublethal damage, has been largely overlooked in the application of BNCT. Recoil protons from fast neutrons vary in their relative biological effectiveness (RBE) as a function of energy and tissue endpoint. Thus the energy spectrum of a beam will influence the RBE of this dose component. Protons from the neutron capture reaction in nitrogen have not been studied but in practice protons from nitrogen capture have been combined with the recoil proton contribution into a total proton dose. The relative biological effectiveness of the products of the neutron capture reaction in boron is derived from two factors, the RBE of the short range particles and the bio-distribution of boron, referred to collectively as the compound biological effectiveness factor. Caution is needed in the application of these factors for different normal tissues and tumors. - Highlights: ► Radiobiological properties of different dose components in BNCT are considered. ► Effectiveness of γ-ray dose depends strongly on exposure time due to sublethal damage repair. ► Effectiveness of fast neutron dose depends on neutron energy spectrum. ► γ-ray and fast neutron characteristics vary between beams and thus weighting factors will differ. ► Weighing factors for boron dose depend on the carrier, the tissue and its mode of administration.

  13. FAST PYROLYSIS OF LIGNINS

    OpenAIRE

    Sedat Beis; Saikrishna Mukkamala; Nathan Hill; Jincy Joseph; Cirila Baker; Bruce Jensen; Elizabeth Stemmler; Clayton Wheeler; Brian Frederick; Adriaan van Heiningen; Alex Berg; William Joseph DeSisto

    2010-01-01

    Three lignins: Indulin AT, LignoboostTM, and Acetocell lignin, were characterized and pyrolyzed in a continuous-fed fast pyrolysis process. The physical and chemical properties of the lignins included chemical composition, heat content, ash, and water content. The distributed activation energy model (DAEM) was used to describe the pyrolysis of each lignin. Activation energy distributions of each lignin were quite different and generally covered a broad range of energies, typically found in li...

  14. Fast Air Temperature Sensors

    DEFF Research Database (Denmark)

    Hendricks, Elbert

    1998-01-01

    The note documents briefly work done on a newly developed sensor for making fast temperature measurements on the air flow in the intake ports of an SI engine and in the EGR input line. The work reviewed has been carried out in close cooperation with Civ. Ing. Michael Føns, the author (IAU......) and Spencer C. Sorenson (ET). The theory which decribes in detail the overall dynamic chracteristics of the sensor was developed at IAU, DTU....

  15. The Integral Fast Reactor

    International Nuclear Information System (INIS)

    The Integral Fast Reactor (IFR) is an innovative liquid metal reactor concept being developed at Argonne National Laboratory. It seeks to specifically exploit the inherent properties of liquid metal cooling and metallic fuel in a way that leads to substantial improvements in the characteristics of the complete reactor system. This paper describes the key features and potential advantages of the IFR concept, with emphasis on its safety characteristics. 3 refs., 4 figs., 1 tab

  16. Fast fission phenomenon

    Science.gov (United States)

    In these lectures we have described two different phenomena occuring in dissipative heavy ion collisions : neutron-proton asymmetry and fast fission. Neutron-proton asymmetry has provided us with an example of a fast collective motion. As a consequence quantum fluctuations can be observed. The observation of quantum or statistical fluctuations is directly connected to the comparison between the phonon energy and the temperature of the intrinsic system. This means that this mode might also provide a good example for the investigation of the transition between quantum and statistical fluctuations which might occur when the bombarding energy is raised above 10 MeV/A. However it is by no means sure that in this energy domain enough excitation energy can be put into the system in order to reach such high temperatures over the all system. The other interest in investigating neutron-proton asymmetry above 10 MeV/A is that the interaction time between the two incident nuclei will decrease. Consequently, if some collective motion should still be observed, it will be one of the last which can be seen. Fast fission corresponds on the contrary to long interaction times. The experimental indications are still rather weak and mainly consist of experimental data which cannot be understood in the framework of standard dissipative models. We have seen that a model which can describe both the entrance and the exit configuration gives this mechanism in a natural way and that the experimental data can, to a good extend, be explained. The nicest thing is probably that our old understanding of dissipative heavy ion collisions is not changed at all except for the problems that can now be understood in terms of fast fission. Nevertheless this area desserve further studies, especially on the experimental side to be sure that the consistent picture which we have on dissipative heavy ion collisions still remain coherent in the future.

  17. Fast synthesis of rare-earth (Pr{sup 3+}, Sm{sup 3+}, Eu{sup 3+} and Gd{sup 3+}) doped bismuth ferrite powders with enhanced magnetic properties

    Energy Technology Data Exchange (ETDEWEB)

    Iorgu, A.I. [Department of Chemical Thermodynamics, “Ilie Murgulescu” Institute of Physical Chemistry, 060021 Bucharest (Romania); Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry, University “Politehnica” of Bucharest, 011061 Bucharest (Romania); Maxim, F., E-mail: fmaxim@icf.ro [Department of Chemical Thermodynamics, “Ilie Murgulescu” Institute of Physical Chemistry, 060021 Bucharest (Romania); Matei, C. [Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry, University “Politehnica” of Bucharest, 011061 Bucharest (Romania); Ferreira, Liliana Pires [Centro de Física da Matéria Condensada, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa (Portugal); Department of Physics, University of Coimbra, 3004-516 Coimbra (Portugal); Ferreira, P. [Department of Materials and Ceramics Engineering, CICECO, Universidade de Aveiro, 3810-193 Aveiro (Portugal); Cruz, M.M. [Centro de Física da Matéria Condensada, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa (Portugal); Departamento de Física, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa (Portugal); Berger, D., E-mail: danaberger01@yahoo.com [Department of Inorganic Chemistry, Physical Chemistry and Electrochemistry, University “Politehnica” of Bucharest, 011061 Bucharest (Romania)

    2015-04-25

    Highlights: • Synthesis of rare earth doped bismuth ferrite powders by combustion method. • SEM and TEM were used to investigate the morphology and size of particles. • Effect of Bi substitution with Pr, Sm, Eu and Gd on magnetic properties of powders. - Abstract: Rare-earth (Pr{sup 3+}, Sm{sup 3+}, Eu{sup 3+} and Gd{sup 3+}) doped bismuth ferrite powders were synthesized for the first time by solution combustion method, which is a fast soft chemistry route for obtaining oxide powders. The materials were investigated by X-ray diffraction, Raman spectroscopy, as well as scanning and transmission electron microscopy. A distortion from rhombohedral R3c symmetry, specific to pure bismuth ferrite, to orthorhombic symmetry was observed for all doped samples. The SEM analysis of pure and doped bismuth ferrite powders showed the formation of sintered grains, with faceted cuboids-shaped particles with different size and lower average dimension in the case of doped samples. Magnetic properties were analyzed using SQUID magnetometry, M–H hysteresis loops being measured at 10 K and 300 K. All studied pure and doped bismuth ferrite samples presented high susceptibility values for high magnetic fields indicating strong antiferromagnetic interactions, whereas the behavior at low magnetic field demonstrates the existence of ferromagnetic coupling. Compared to BiFeO{sub 3}, Bi{sub 0.9}RE{sub 0.1}FeO{sub 3} (RE = Pr, Sm, Eu and Gd) powders exhibit higher susceptibility, remanence and coercivity values, Bi{sub 0.9}Eu{sub 0.1}FeO{sub 3} sample displaying the highest remanence and coercivity at room temperature.

  18. ADT fast losses MD

    CERN Document Server

    Priebe, A; Dehning, B; Redaelli, S; Salvachua Ferrando, BM; Sapinski, M; Solfaroli Camillocci, M; Valuch, D

    2013-01-01

    The fast beam losses in the order of 1 ms are expected to be a potential major luminosity limitation for higher beam energies after the LHC long shutdown (LS1). Therefore a Quench Test is planned in the winter 2013 to estimate the quench limit in this timescale and revise the current models. This experiment was devoted to determination the LHC Transverse Damper (ADT) as a system for fast losses induction. A non-standard operation of the ADT was used to develop the beam oscillation instead of suppressing them. The sign flip method had allowed us to create the fast losses within several LHC turns at 450 GeV during the previous test (26th March 2012). Thus, the ADT could be potentially used for the studies of the UFO ("Unidentied Falling Object") impact on the cold magnets. Verification of the system capability and investigations of the disturbed beam properties were the main objectives of this MD. During the experiment, the pilot bunches of proton beam were excited independently in the horizontal and vertical ...

  19. Development and Characterization of a High Sensitivity Segmented Fast Neutron Spectrometer (FaNS-2)

    OpenAIRE

    FaNS Collaboration; Langford, T. J.; Beise, E. J.; Breuer, H.; Heimbach, C. R.; Ji, G; Nico, J. S.

    2015-01-01

    We present the development of a segmented fast neutron spectrometer (FaNS-2) based upon plastic scintillator and $^3$He proportional counters. It was designed to measure both the flux and spectrum of fast neutrons in the energy range of few MeV to 1 GeV. FaNS-2 utilizes capture-gated spectroscopy to identify neutron events and reject backgrounds. Neutrons deposit energy in the plastic scintillator before capturing on a $^3$He nucleus in the proportional counters. Segmentation improves neutron...

  20. Indian fast reactor technology: Current status and future programme

    Indian Academy of Sciences (India)

    S C Chetal; P Chellapandi

    2013-10-01

    The paper brings out the advantages of fast breeder reactor and importance of developing closed nuclear fuel cycle for the large scale energy production, which is followed by its salient safety features. Further, the current status and future strategy of the fast reactor programme since the inception through 40 MWt/13 MWe Fast Breeder Test Reactor (FBTR), is highlighted. The challenges and achievements in science and technology of FBRs focusing on safety are described with the particular reference to 500 MWe capacity Prototype Fast Breeder Reactor (PFBR), being commissioned at Kalpakkam. Roadmap with comprehensive R&D for the large scale deployment of Sodium Cooled Fast Reactor (SFRs) and timely introduction of metallic fuel reactors with emphasis on breeding gain and enhanced safety are being brought out in this paper.