WorldWideScience

Sample records for selective absorption system

  1. Sulfur K-edge absorption spectroscopy on selected biological systems

    International Nuclear Information System (INIS)

    Lichtenberg, Henning

    2008-07-01

    Sulfur is an essential element in organisms. In this thesis investigations of sulfur compounds in selected biological systems by XANES (X-ray Absorption Near Edge Structure) spectroscopy are reported. XANES spectroscopy at the sulfur K-edge provides an excellent tool to gain information about the local environments of sulfur atoms in intact biological samples - no extraction processes are required. Spatially resolved measurements using a Kirkpatrick-Baez mirror focusing system were carried out to investigate the infection of wheat leaves by rust fungi. The results give information about changes in the sulfur metabolism of the host induced by the parasite and about the extension of the infection into visibly uninfected plant tissue. Furthermore, XANES spectra of microbial mats from sulfidic caves were measured. These mats are dominated by microbial groups involved in cycling sulfur. Additionally, the influence of sulfate deprivation and H 2 S exposure on sulfur compounds in onion was investigated. To gain an insight into the thermal degradation of organic material the influence of roasting of sulfur compounds in coffee beans was studied. (orig.)

  2. Absorption heat pump system

    Science.gov (United States)

    Grossman, G.

    1982-06-16

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  3. Sulfur K-edge absorption spectroscopy on selected biological systems; Schwefel-K-Kanten-Absorptionsspektroskopie an ausgewaehlten biologischen Systemen

    Energy Technology Data Exchange (ETDEWEB)

    Lichtenberg, Henning

    2008-07-15

    Sulfur is an essential element in organisms. In this thesis investigations of sulfur compounds in selected biological systems by XANES (X-ray Absorption Near Edge Structure) spectroscopy are reported. XANES spectroscopy at the sulfur K-edge provides an excellent tool to gain information about the local environments of sulfur atoms in intact biological samples - no extraction processes are required. Spatially resolved measurements using a Kirkpatrick-Baez mirror focusing system were carried out to investigate the infection of wheat leaves by rust fungi. The results give information about changes in the sulfur metabolism of the host induced by the parasite and about the extension of the infection into visibly uninfected plant tissue. Furthermore, XANES spectra of microbial mats from sulfidic caves were measured. These mats are dominated by microbial groups involved in cycling sulfur. Additionally, the influence of sulfate deprivation and H{sub 2}S exposure on sulfur compounds in onion was investigated. To gain an insight into the thermal degradation of organic material the influence of roasting of sulfur compounds in coffee beans was studied. (orig.)

  4. Selective gas absorption by ionic liquids

    DEFF Research Database (Denmark)

    Shunmugavel, Saravanamurugan; Kegnæs, Søren; Due-Hansen, Johannes

    2010-01-01

    Reversible absorption performance for the flue gas components CO 2, NO and SO2 has been tested for several different ionic liquids (ILs) at different temperatures and flue gas compositions. Furthermore, different porous, high surface area carriers have been applied as supports for the ionic liquids...... to obtain Supported Ionic Liquid-Phase (SILP) absorber materials. The use of solid SILP absorbers with selected ILs were found to significantly improve the absorption capacity and sorption dynamics at low flue gas concentration, thus making the applicability of ILs viable in technical, continuous flow...... processes for flue gas cleaning. The results show that CO 2, NO and SO2 can be reversible and selective absorbed using different ILs and that Supported Ionic Liquid-Phase (SILP) absorbers are promising materials for industrial flue gas cleaning. Absorption/desorption dynamics can be tuned by temperatures...

  5. Optical absorption measurement system

    International Nuclear Information System (INIS)

    Draggoo, V.G.; Morton, R.G.; Sawicki, R.H.; Bissinger, H.D.

    1989-01-01

    This patent describes a non-intrusive method for measuring the temperature rise of optical elements under high laser power optical loading to determine the absorption coefficient. The method comprises irradiating the optical element with a high average power laser beam, viewing the optical element with an infrared camera to determine the temperature across the optical element and calculating the absorption of the optical element from the temperature

  6. Absorption-heat-pump system

    Science.gov (United States)

    Grossman, G.; Perez-Blanco, H.

    1983-06-16

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  7. Uniform semiclassical approximation for absorptive scattering systems

    International Nuclear Information System (INIS)

    Hussein, M.S.; Pato, M.P.

    1987-07-01

    The uniform semiclassical approximation of the elastic scattering amplitude is generalized to absorptive systems. An integral equation is derived which connects the absorption modified amplitude to the absorption free one. Division of the amplitude into a diffractive and refractive components is then made possible. (Author) [pt

  8. Superwetting nanowire membranes for selective absorption.

    Science.gov (United States)

    Yuan, Jikang; Liu, Xiaogang; Akbulut, Ozge; Hu, Junqing; Suib, Steven L; Kong, Jing; Stellacci, Francesco

    2008-06-01

    The construction of nanoporous membranes is of great technological importance for various applications, including catalyst supports, filters for biomolecule purification, environmental remediation and seawater desalination. A major challenge is the scalable fabrication of membranes with the desirable combination of good thermal stability, high selectivity and excellent recyclability. Here we present a self-assembly method for constructing thermally stable, free-standing nanowire membranes that exhibit controlled wetting behaviour ranging from superhydrophilic to superhydrophobic. These membranes can selectively absorb oils up to 20 times the material's weight in preference to water, through a combination of superhydrophobicity and capillary action. Moreover, the nanowires that form the membrane structure can be re-suspended in solutions and subsequently re-form the original paper-like morphology over many cycles. Our results suggest an innovative material that should find practical applications in the removal of organics, particularly in the field of oil spill cleanup.

  9. The low-ion QSO absorption-line systems

    International Nuclear Information System (INIS)

    Lanzetta, K.M.

    1988-01-01

    Various techniques are used to investigate the class of QSO absorption-line systems that exhibit low-ion absorption lines. Four separate investigations are conducted as follows: Spectroscopy of 32 QSOs at red wavelengths is presented and used to investigate intermediate-redshift MgII absorption. A total of 22 Mg II doublets are detected, from which properties of the Mg II absorbers are derived. Marginal evidence for intrinsic evolution of the number density of the Mg II absorbers with redshift is found. The data are combined with previous observations of C IV and C II seen in the same QSOs at blue wavelengths, and the properties of Mg II- and C IV-selected systems are compared. A sample is constructed of 129 QSOs for which are available published data suitable for detecting absorption-line systems that are optically thick to Lyman continuum radiation. A total of 53 such Lyman-limit systems are found, from which properties of the Lyman-limit systems are derived. It is found that the rate of incidence of the systems does not strongly evolved with redshift. This result is contrasted with the evolution found previously for systems selected on the basis of Mg II absorption. Spectroscopy at red wavelengths of eight QSOs with known damped Lyα absorption systems is presented. Spectroscopic and spectrophotometric observations aimed at detecting molecular hydrogen and dust in the z = 2.796 damped Lyα absorber toward Q1337 + 113 are presented

  10. Systemic Absorption of Nanomaterials by Oral Exposure

    DEFF Research Database (Denmark)

    Binderup, Mona-Lise; Bredsdorff, Lea; Beltoft, Vibe Meister

    This report and accompanying database systematically evaluates the reliability and relevance of the existing scientific literature regarding systemic absorption of nanomaterials by oral exposure and makes specific recommendations for future testing approaches.......This report and accompanying database systematically evaluates the reliability and relevance of the existing scientific literature regarding systemic absorption of nanomaterials by oral exposure and makes specific recommendations for future testing approaches....

  11. ALMACAL - III. A combined ALMA and MUSE survey for neutral, molecular, and ionized gas in an H I-absorption-selected system

    Science.gov (United States)

    Klitsch, A.; Péroux, C.; Zwaan, M. A.; Smail, I.; Oteo, I.; Biggs, A. D.; Popping, G.; Swinbank, A. M.

    2018-03-01

    Studying the flow of baryons into and out of galaxies is an important part of understanding the evolution of galaxies over time. We present a detailed case study of the environment around an intervening Ly α absorption line system at zabs = 0.633, seen towards the quasar J0423-0130 (zQSO = 0.915). We detect with ALMA the 12CO(2-1), 12CO(3-2), and 1.2 mm continuum emission from a galaxy at the redshift of the Ly α absorber at a projected distance of 135 kpc. From the ALMA detections, we infer interstellar medium conditions similar to those in low-redshift luminous infrared galaxies. Director's Discretionary Time (DDT) Multi-Unit Spectroscopic Explorer (MUSE) integral field unit observations reveal the optical counterpart of the 12CO emission line source and three additional emission line galaxies at the absorber redshift, which together form a galaxy group. The 12CO emission line detections originate from the most massive galaxy in this group. While we cannot exclude that we miss a fainter host, we reach a dust-uncorrected star formation rate (SFR) limit of >0.3 M⊙yr-1 within 100 kpc from the sightline to the background quasar. We measure the dust-corrected SFR (ranging from 3 to 50 M⊙ yr-1), the morpho-kinematics and the metallicities of the four group galaxies to understand the relation between the group and the neutral gas probed in absorption. We find that the Ly α absorber traces either an outflow from the most massive galaxy or intragroup gas. This case study illustrates the power of combining ALMA and MUSE to obtain a census of the cool baryons in a bounded structure at intermediate redshift.

  12. Cosmological implications of the redshift distribution of QSO absorption systems

    International Nuclear Information System (INIS)

    Khare-Joshi, P.; Perry, J.J.

    1982-01-01

    We have used the observational data on QSO absorption redshifts, as compiled by Perry, Burbidge and Burbidge (1978) (hereafter PB 2 ), Drew (1978) and Weyman et al. (1979) (hereafter W 2 PT), to study various selection effects likely to affect the distribution of absorption redshifts and, then to determine the probable number distribution of absorbers per redshift interval of 0.1, as a function of z. The distribution obtained, assuming all the observed absorption to be intervening, is found to be statistically incompatible with the redshift distribution of galaxies with constant cross-section for any Friedman cosmology with zero cosmological constant and q 0 >= 0. Therefore, in order to eliminate the absorption systems which are plausibly intrinsic, we have applied the criterion suggested by W 2 PT and by the analysis of the distribution of absorption systems as a function of the relative velocity between the emitting and the absorbing gas, for the PB 2 data set; to wit, we have analysed the distributions obtained by assuming that those systems with relative velocity greater than 0.02 c, 0.02 c but not equal to 0.1 c to 0.11 c and 0.06 c respectively, or those systems without O VI and N V lines, are produced by the intervening galaxies. The results are discussed. (author)

  13. Performance of Active Wave Absorption Systems

    DEFF Research Database (Denmark)

    Hald, Tue; Frigaard, Peter

    on a horisontal and vertical velocity are treated. All three systems are based on digital FIR-filters. For numerical comparison a performance function combining the frequency response of the set of filters for each system is derived enabling discussion on optimal filter design and system setup. Irregular wave......A comparison of wave gauge based on velocity meter based active absorption systems is presented discussing advantages and disadvantages of the systems. In detail one system based on two surface elevations, one system based on a surface elevation and a horisontal velocity and one system based...... tests with a highly reflective structure with the purely wave gauge based system and the wave gauge velocity meter based system are performed. The wave test depict the differences between the systems....

  14. Cosmological Evolution of QSO Absorption Systems

    Science.gov (United States)

    Stengler-Larrea, Erik

    1995-08-01

    First, the evolution with cosmic time of the hydrogen clouds which produce the Lyman-alpha absorption lines is studied in dependence on the strength of these lines. From the analysis it is concluded that the results show no evidence of a dependence in the sense of stronger lines evolving faster, although for the resolution at which the used observations were done, it can not be ruled out. Within the same analysis, a distribution of the Doppler parameter of the lines was obtained, with large values and a wide spread. This parameter being an indicator of the gas temperature, this result is in accordance with high temperatures and, consequently, large ionised fractions and a large fraction of the baryonic matter of the universe being associated with these clouds. However, recent high resolution studies seem to reveal that much lower temperatures are characteristic of the clouds. The main content of this thesis, however, focuses on the redshift evolution of the absorbing systems producing absorption at the Lyman limit and of the amount of CIV producing CIV absorption lines. Regarding the CIV absorbers, previous predictions on the effects underlying their redshift distribution pointed to an increase with redshift of the absorbing column densities. In this thesis the first direct measurements of such column densities by profile fitting of a large number of absorption systems (73) are presented, confirming the predictions of a decrease of at least a factor of 3 between z=1.5 and z=3.0. The study on the evolution of Lyman limit absorption systems (LLSs) puts an end to previous discrepancies between the results of different groups. Both a smooth single power law dependence of the LLS number density on redshift indicating no evolution in number density for 0.4 Team of the HST Key Project on QSO absorption lines, and in particular to estimate the necessary exposure times, the magnitudes of several of these objects had to be re-measured. The acquisition of their images and the

  15. Endovascular vein harvest: systemic carbon dioxide absorption.

    Science.gov (United States)

    Maslow, Andrew M; Schwartz, Carl S; Bert, Arthur; Hurlburt, Peter; Gough, Jeffrey; Stearns, Gary; Singh, Arun K

    2006-06-01

    Endovascular vein harvest (EDVH) requires CO(2) insufflation to expand the subcutaneous space, allowing visualization and dissection of the saphenous vein. The purpose of this study was to assess the extent of CO(2) absorption during EDVH. Prospective observational study. Single tertiary care hospital. Sixty patients (30 EDVH and 30 open-vein harvest) undergoing isolated coronary artery bypass graft surgery. Hemodynamic, procedural, and laboratory data were collected prior to (baseline), during, and at it the conclusion (final) of vein harvesting. Data were also collected during cardiopulmonary bypass (CPB). Data were compared by using t tests, analysis of variance, and correlation statistics when needed. There were significant increases in arterial CO(2) (PaCO(2), 35%) and decreases in pH (1.35%) during EDVH. These were associated with increases in heart rate, mean blood pressure, and cardiac output. Within the EDVH group, greater elevations (>10 mmHg) in PaCO2 were more likely during difficult harvest procedures, and these patients exhibited greater increase in heart rate. Elevated CO(2) persisted during CPB, requiring higher systemic gas flows and greater use of phenylephrine to maintain desired hemodynamics. EDVH was associated with systemic absorption of CO(2). Greater absorption was more likely in difficult procedures and was associated with greater hemodynamic changes requiring medical therapy.

  16. Broadband Reflectionless Metasheets: Frequency-Selective Transmission and Perfect Absorption

    Directory of Open Access Journals (Sweden)

    V. S. Asadchy

    2015-07-01

    Full Text Available Energy of propagating electromagnetic waves can be fully absorbed in a thin lossy layer, but only in a narrow frequency band, as follows from the causality principle. On the other hand, it appears that there are no fundamental limitations on broadband matching of thin resonant absorbing layers. However, known thin absorbers produce significant reflections outside of the resonant absorption band. In this paper, we explore possibilities to realize a thin absorbing layer that produces no reflected waves in a very wide frequency range, while the transmission coefficient has a narrow peak of full absorption. Here we show, both theoretically and experimentally, that a thin resonant absorber, invisible in reflection in a very wide frequency range, can be realized if one and the same resonant mode of the absorbing array unit cells is utilized to create both electric and magnetic responses. We test this concept using chiral particles in each unit cell, arranged in a periodic planar racemic array, utilizing chirality coupling in each unit cell but compensating the field coupling at the macroscopic level. We prove that the concept and the proposed realization approach also can be used to create nonreflecting layers for full control of transmitted fields. Our results can have a broad range of potential applications over the entire electromagnetic spectrum including, for example, perfect ultracompact wave filters and selective multifrequency sensors.

  17. Analysis of a solar powered absorption system

    International Nuclear Information System (INIS)

    Said, S.A.M.; El-Shaarawi, M.A.I.; Siddiqui, M.U.

    2015-01-01

    Highlights: • Conventional absorption system modified to increase COP. • Results indicated increase of 10% in COP due to dephlegmator heat recovery. • Results indicated increase of 8% in COP due to refrigerant storage unit. • Results indicated increase of 18% in COP due to combined effect of modifications. • Simulation results indicated a very good agreement with the measured results. - Abstract: Today, fossil fuel is the primary extensively used source of energy. However, its negative impact on the environment have forced the energy research continuity to seriously consider renewable sources of energy. Solar energy, in particular, has been the main focus in this regard because it is a source of clean energy and naturally available. This study presents the design and analysis of a solar powered absorption refrigeration system modified to increase its coefficient of performance (COP). The modifications include recovering of waste heat from a dephlegmator and utilization of a refrigerant storage unit. The simulation results indicate an increase of 10% in the COP of the conventional design using dephlegmator heat recovery and an increase of 8% in the COP of the conventional design due to the use of a refrigerant storage. The analysis for the combined effect of modifications indicates an increase of 18% in the COP compared to conventional design. Calculated values of coefficient of performance indicate a very good agreement with the ones obtained based on measurement

  18. Guided-wave approaches to spectrally selective energy absorption

    Science.gov (United States)

    Stegeman, G. I.; Burke, J. J.

    1987-01-01

    Results of experiments designed to demonstrate spectrally selective absorption in dielectric waveguides on semiconductor substrates are reported. These experiments were conducted with three waveguides formed by sputtering films of PSK2 glass onto silicon-oxide layers grown on silicon substrates. The three waveguide samples were studied at 633 and 532 nm. The samples differed only in the thickness of the silicon-oxide layer, specifically 256 nm, 506 nm, and 740 nm. Agreement between theoretical predictions and measurements of propagation constants (mode angles) of the six or seven modes supported by these samples was excellent. However, the loss measurements were inconclusive because of high scattering losses in the structures fabricated (in excess of 10 dB/cm). Theoretical calculations indicated that the power distribution among all the modes supported by these structures will reach its steady state value after a propagation length of only 1 mm. Accordingly, the measured loss rates were found to be almost independent of which mode was initially excited. The excellent agreement between theory and experiment leads to the conclusion that low loss waveguides confirm the predicted loss rates.

  19. Ion competition effects on the selective absorption of radionuclides by komatsuna (Brassica rapa var. perviridis)

    International Nuclear Information System (INIS)

    Ambe, S.; Shinonaga, T.; Ozaki, T.; Enomoto, S.; Yasuda, H.; Uchida, S.

    1999-01-01

    The selective absorption coefficient, which is a parameter of an uptake model of radionuclides by plants, was determined for various radionuclides by a multitracer technique. Komatsuna, Brassica rapa var. perviridis, was hydroponically cultivated in a nutrient solution containing a multitracer for 1 day. Nutrient concentration dependence of the selective absorption coefficient of various elements from Be to Re was obtained separately for leaves and roots. The selective absorption coefficients of these elements were, in general, found to decrease with an increase in the concentration of nutrient solutions. Regression equations of the power function for the selective absorption coefficients and the concentration of nutrient solutions were obtained for the leaves and roots. The effects of photon flux and growth stage of plants on the selective absorption coefficients were also studied. It was found that the photon flux influenced the accumulation of radionuclides in the roots but had no significant effect on the selective absorption coefficients for the leaves in 1-day cultivation with the multitracer. The selective absorption coefficients of Mn and Zn in the leaves of the plants at the development stage were higher than those at the maturation stage. For the other elements, no significant effects of the growth stage on the selective absorption coefficients were observed. (author)

  20. Gintonin absorption in intestinal model systems

    Directory of Open Access Journals (Sweden)

    Byung-Hwan Lee

    2018-01-01

    Conclusion: The present study shows that gintonin could be absorbed in the intestine through transcellular and paracellular diffusion, and active transport. In addition, the lipid component of gintonin might play a key role in its intestinal absorption.

  1. Simulation of absorption refrigeration system for automobile application

    Directory of Open Access Journals (Sweden)

    Ramanathan Anand

    2008-01-01

    Full Text Available An automotive air-conditioning system based on absorption refrigeration cycle has been simulated. This waste heat driven vapor absorption refrigeration system is one alternate to the currently used vapour compression refrigeration system for automotive air-conditioning. Performance analysis of vapor absorption refrigeration system has been done by developing a steady-state simulation model to find the limitation of the proposed system. The water-lithium bromide pair is used as a working mixture for its favorable thermodynamic and transport properties compared to the conventional refrigerants utilized in vapor compression refrigeration applications. The pump power required for the proposed vapor absorption refrigeration system was found lesser than the power required to operate the compressor used in the conventional vapor compression refrigeration system. A possible arrangement of the absorption system for automobile application is proposed.

  2. Cloud Absorption Radiometer Autonomous Navigation System - CANS

    Science.gov (United States)

    Kahle, Duncan; Gatebe, Charles; McCune, Bill; Hellwig, Dustan

    2013-01-01

    CAR (cloud absorption radiometer) acquires spatial reference data from host aircraft navigation systems. This poses various problems during CAR data reduction, including navigation data format, accuracy of position data, accuracy of airframe inertial data, and navigation data rate. Incorporating its own navigation system, which included GPS (Global Positioning System), roll axis inertia and rates, and three axis acceleration, CANS expedites data reduction and increases the accuracy of the CAR end data product. CANS provides a self-contained navigation system for the CAR, using inertial reference and GPS positional information. The intent of the software application was to correct the sensor with respect to aircraft roll in real time based upon inputs from a precision navigation sensor. In addition, the navigation information (including GPS position), attitude data, and sensor position details are all streamed to a remote system for recording and later analysis. CANS comprises a commercially available inertial navigation system with integral GPS capability (Attitude Heading Reference System AHRS) integrated into the CAR support structure and data system. The unit is attached to the bottom of the tripod support structure. The related GPS antenna is located on the P-3 radome immediately above the CAR. The AHRS unit provides a RS-232 data stream containing global position and inertial attitude and velocity data to the CAR, which is recorded concurrently with the CAR data. This independence from aircraft navigation input provides for position and inertial state data that accounts for very small changes in aircraft attitude and position, sensed at the CAR location as opposed to aircraft state sensors typically installed close to the aircraft center of gravity. More accurate positional data enables quicker CAR data reduction with better resolution. The CANS software operates in two modes: initialization/calibration and operational. In the initialization/calibration mode

  3. Selecting a silvicultural system

    Science.gov (United States)

    Richard M. Godman

    1992-01-01

    Sometimes a name creates a problem. The name of a silvicultural system usually refers to the way a stand is cut to get regeneration-"single tree selection"-for example. Trouble is, the name suggests that the regeneration cut will be the first treatment applied to the stand. Not so. We are now mostly making "intermediate" cuts in our Lake States...

  4. Model systems for understanding absorption tuning by opsin proteins

    DEFF Research Database (Denmark)

    Nielsen, Mogens Brøndsted

    2009-01-01

    This tutorial review reports on model systems that have been synthesised and investigated for elucidating how opsin proteins tune the absorption of the protonated retinal Schiff base chromophore. In particular, the importance of the counteranion is highlighted. In addition, the review advocates...... is avoided, and it becomes clear that opsin proteins induce blueshifts in the chromophore absorption rather than redshifts....

  5. The Role of Absorption Cooling for Reaching Sustainable Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Lindmark, Susanne

    2005-07-01

    This thesis focuses on the role and potential of absorption cooling in future energy systems. Two types of energy systems are investigated: a district energy system based on waste incineration and a distributed energy system with natural gas as fuel. In both cases, low temperature waste heat is used as driving energy for the absorption cooling. The main focus is to evaluate the absorption technology in an environmental perspective, in terms of reduced CO{sub 2} emissions. Economic evaluations are also performed. The reduced electricity when using absorption cooling instead of compression cooling is quantified and expressed as an increased net electrical yield. The results show that absorption cooling is an environmentally friendly way to produce cooling as it reduces the use of electrically driven cooling in the energy system and therefore also reduces global CO{sub 2} emissions. In the small-scale trigeneration system the electricity use is lowered with 84 % as compared to cooling production with compression chillers only. The CO{sub 2} emissions can be lowered to 45 CO{sub 2}/MWh{sub c} by using recoverable waste heat as driving heat for absorption chillers. However, the most cost effective cooling solution in a district energy system is a combination between absorption and compression cooling technologies according to the study. Absorption chillers have the potential to be suitable bottoming cycles for power production in distributed systems. Net electrical yields over 55 % may be reached in some cases with gas motors and absorption chillers. This small-scale system for cogeneration of power and cooling shows electrical efficiencies comparable to large-scale power plants and may contribute to reducing peak electricity demand associated with the cooling demand.

  6. Optical performance and metallic absorption in nanoplasmonic systems.

    Science.gov (United States)

    Arnold, Matthew D; Blaber, Martin G

    2009-03-02

    Optical metrics relating to metallic absorption in representative plasmonic systems are surveyed, with a view to developing heuristics for optimizing performance over a range of applications. We use the real part of the permittivity as the independent variable; consider strengths of particle resonances, resolving power of planar lenses, and guiding lengths of planar waveguides; and compare nearly-free-electron metals including Al, Cu, Ag, Au, Li, Na, and K. Whilst the imaginary part of metal permittivity has a strong damping effect, field distribution is equally important and thus factors including geometry, real permittivity and frequency must be considered when selecting a metal. Al performs well at low permittivities (e.g. sphere resonances, superlenses) whereas Au & Ag only perform well at very negative permittivities (shell and rod resonances, LRSPP). The alkali metals perform well overall but present engineering challenges.

  7. Absorption solar cooling systems using optimal driving temperatures

    International Nuclear Information System (INIS)

    Lecuona, Antonio; Ventas, Rubén; Vereda, Ciro; López, Ricardo

    2015-01-01

    The optimum instantaneous driving temperature of a solar cooling facility is determined along a day. The chillers compared use single effect cycles working with NH 3 /LiNO 3 , either conventional or hybridised by incorporating a low pressure booster compressor. Their performances are compared with a H 2 O/LiBr single effect absorption chiller as part of the same solar system. The results of a detailed thermodynamic cycle for the absorption chillers allow synthesizing them in a modified characteristic temperature difference model. The day accumulated solar cold production is determined using this optimum temperature during two sunny days in mid-July and mid-September, located in Madrid, Spain. The work shows the influences of operational variables and a striking result: selection of a time-constant temperature during all the day does not necessarily imply a substantial loss, being the temperature chosen a key parameter. The results indicate that the NH 3 /LiNO 3 option with no boosting offers a smaller production above-zero Celsius degrees temperatures, but does not require higher hot water driving temperatures than H 2 O/LiBr. The boosted cycle offers superior performance. Some operational details are discussed. - Highlights: • Instantaneous optimum driving temperature t g,op for solar cooling in Madrid. • 3 absorption cycles tested: H 2 O/LiBr and NH 3 /LiNO 3 single effect and hybrid. • The t g,op of the hybrid cycle is 16 °C lower than both single effect cycles. • The best fixed driving temperature can reach almost the same behaviour than t g,op

  8. Differential Absorption as a Factor Influencing the Selective Toxicity of MCPA and MCPB

    Energy Technology Data Exchange (ETDEWEB)

    Kirkwood, R. C.; Robertson, M. M.; Smith, J. E. [University of Strathclyde, Glasgow (United Kingdom)

    1966-05-15

    enhanced inhibitory effect of this herbicide. In addition it was found that mitochondria extracted from this mycelium of A. niger grown in a nutrient-herbicide medium showed a greater absorption of MCPB than MCPA. These results have great significance since it has been shown that the mitochondria are the probable site of toxic action of these compounds in A. niger. It was tentatively concluded from these early experiments that differential absorption was a factor influencing toxicity of these two herbicides, but that this would be additional to the selectivity resulting from the widely accepted {beta} -oxidizing enzyme system. (author)

  9. Artificial neural network analysis of triple effect absorption refrigeration systems

    Energy Technology Data Exchange (ETDEWEB)

    Hajizadeh Aghdam, A. [Department of Mechanical Engineering, Islamic Azad University (Iran, Islamic Republic of)], email: a.hajizadeh@iaukashan.ac.ir; Nazmara, H.; Farzaneh, B. [Department of Mechanical Engineering, University of Tabriz (Iran, Islamic Republic of)], email: h.nazmara@nioec.org, email: b_farzaneh_ms@yahoo.com

    2011-07-01

    In this study, artificial neural networks are utilized to predict the performance of triple effect series and parallel flow absorption refrigeration systems, with lithium bromide/water as the working fluid. Important parameters such as high generator and evaporator temperatures were varied and their effects on the performance characteristics of the refrigeration unit were observed. Absorption refrigeration systems make energy savings possible because they can use heat energy to produce cooling, in place of the electricity used for conventional vapour compression chillers. In addition, non-conventional sources of energy (such as solar, waste heat, and geothermal) can be utilized as their primary energy input. Moreover, absorption units use environmentally friendly working fluid pairs instead of CFCs and HCFCs, which affect the ozone layer. Triple effect absorption cycles were analysed. Results apply for both series and parallel flow systems. A relative preference for parallel-flow over series-flow is also shown.

  10. The distribution of absorptive power dissipation in irradiated nanoparticulate system

    International Nuclear Information System (INIS)

    Li, Jiayu; Yang, Jian; Gu, Xiaobing

    2016-01-01

    The knowledge of local radiant absorption is important to the nanostructure optimization, it is beneficial to the applications in energy harvesting, optical heating, photocatalysis, etc. In this paper, FDTD model is constructed for the distribution of absorptive power dissipation in irradiated nanoparticulate system. The theoretical model extended from Mie theory is used to examine the FDTD model, the parameters and conditions set for FDTD simulation are confirmed based on the comparison. Then, the influence of Ag nanoparticle on the absorptive properties of nearby TiO_2 nanoparticle is investigated by FDTD simulation at the wavelength of 0.25 μm. It is indicated that suitable distance between TiO_2 and Ag particles is beneficial to the spectral radiant absorption of TiO_2 particle. Considering the agglomeration of nanoparticles and the oxidation at the TiO_2–Ag interface, the Ag core coated with Al_2O_3 shell is suggested, and the simulated results indicated that the shell thickness and the Ag core size need to be optimized for enhancing the radiant absorption of TiO_2 particle. - Highlights: • The absorptive power distribution in nanoparticulate system is simulated by FDTD. • FDTD simulation is compared with theoretical model extended from Mie theory. • The parameters and conditions are confirmed based on the comparison. • The influence of Ag nanoparticle on nearby TiO_2 particle's absorption is analyzed.

  11. Highly selective population of two excited states in nonresonant two-photon absorption

    International Nuclear Information System (INIS)

    Zhang Hui; Zhang Shi-An; Sun Zhen-Rong

    2011-01-01

    A nonresonant two-photon absorption process can be manipulated by tailoring the ultra-short laser pulse. In this paper, we theoretically demonstrate a highly selective population of two excited states in the nonresonant two-photon absorption process by rationally designing a spectral phase distribution. Our results show that one excited state is maximally populated while the other state population is widely tunable from zero to the maximum value. We believe that the theoretical results may play an important role in the selective population of a more complex nonlinear process comprising nonresonant two-photon absorption, such as resonance-mediated (2+1)-three-photon absorption and (2+1)-resonant multiphoton ionization. (atomic and molecular physics)

  12. Spectrophotometer-Integrating-Sphere System for Computing Solar Absorptance

    Science.gov (United States)

    Witte, William G., Jr.; Slemp, Wayne S.; Perry, John E., Jr.

    1991-01-01

    A commercially available ultraviolet, visible, near-infrared spectrophotometer was modified to utilize an 8-inch-diameter modified Edwards-type integrated sphere. Software was written so that the reflectance spectra could be used to obtain solar absorptance values of 1-inch-diameter specimens. A descriptions of the system, spectral reflectance, and software for calculation of solar absorptance from reflectance data are presented.

  13. Second law analysis of double effect vapour absorption cooler system

    International Nuclear Information System (INIS)

    Gomri, Rabah; Hakimi, Riad

    2008-01-01

    In this paper, exergy analysis of double effect lithium bromide/water absorption refrigeration system is presented. The system consists of a second effect generator between the generator and condenser of the single effect absorption refrigeration system, including two solution heat exchangers between the absorber and the two generators. In order to simulate the refrigeration system by using a computer, a new set of computationally efficient formulations of thermodynamic properties of lithium bromide/water solution developed is used. The exergy analysis is carried out for each component of the system. All exergy losses that exist in double effect lithium bromide/water absorption system are calculated. In addition to the coefficient of performance and the exergetic efficiency of the system, the number of exergy of each component of the system is also estimated. This study suggests the component of the absorption refrigeration system that should be developed. The results show that the performance of the system increases with increasing low pressure generator (LPG) temperature, but decreases with increasing high pressure generator (HPG) temperature. The highest exergy loss occurs in the absorber and in the HPG, which therefore makes the absorber and HPG the most important components of the double effect refrigeration system

  14. Optomechanically induced absorption in parity-time-symmetric optomechanical systems

    Science.gov (United States)

    Zhang, X. Y.; Guo, Y. Q.; Pei, P.; Yi, X. X.

    2017-06-01

    We explore the optomechanically induced absorption (OMIA) in a parity-time- (PT -) symmetric optomechanical system (OMS). By numerically calculating the Lyapunov exponents, we find out the stability border of the PT -symmetric OMS. The results show that in the PT -symmetric phase the system can be either stable or unstable depending on the coupling constant and the decay rate. In the PT -symmetric broken phase the system can have a stable state only for small gain rates. By calculating the transmission rate of the probe field, we find that there is an inverted optomechanically induced transparency (OMIT) at δ =-ωM and an OMIA at δ =ωM for the PT -symmetric optomechanical system. At each side of δ =-ωM there is an absorption window due to the resonance absorption of the two generated supermodes. Comparing with the case of optomechanics coupled to a passive cavity, we find that the active cavity can enhance the resonance absorption. The absorption rate at δ =ωM increases as the coupling strength between the two cavities increases. Our work provides us with a promising platform for controlling light propagation and light manipulation in terms of PT symmetry, which might have potential applications in quantum information processing and quantum optical devices.

  15. Multiple wavelength multitimescale optical absorption system

    International Nuclear Information System (INIS)

    Lubis, R.; Allan, D.; Hodgson, B.W.; Swallow, A.J.

    1992-01-01

    A new workstation for pulse radiolysis studies has been developed for the Paterson Institute Linear Accelerator Laboratory. It is particularly suited to the study of materials available only in limited quantities. The analysing light beam is dispersed into a plane spectrum by a McPherson 270 monochromator and focused down to a line spectrum by a rod lens. The spectral intensity distribution is sampled by a linear array of optical fibres which conduct the light to photodiodes. A preamplifier unit amplifies and buffers the diode photocurrent signal which then passes to the main electronics unit incorporating further amplification stages, filters, backing-off of the background photocurrent, analog-to-digital conversion, data storage memory and a computer interface. All control of the electronic system is performed from a computer equipped with appropriate software. The system has 10 channels of spectral bandwidth 16 nm, a useful spectral response from 350 nm to 1 μm with a high signal-to-noise ratio, signal sampling rates from 20 MHz to 2 kHz and 8 kbyte of local memory for each channel. (author)

  16. Multiple wavelength multitimescale optical absorption system

    Science.gov (United States)

    Lubis, R.; Allan, D.; Hodgson, B. W.; Swallow, A. J.

    A new workstation for pulse radiolysis studies has been developed for the Paterson Institute Linear Accelerator Laboratory. It is particularly suited to the study of materials available only in limited quantities. The analysing light beam is dispersed into a plane spectrum by a McPherson 270 monochromator and focused down to a line spectrum by a rod lens. The spectral intensity distribution is sampled by a linear array of optical fibres which conduct the light to photodiodes. A preamplifier unit amplifies and buffers the diode photocurrent signal which then passes to the main electronics unit incorporating further amplification stages, filters, backing-off of the background photocurrent, analog-to-digital conversion, data storage memory and a computer interface. All control of the electronic system is performed from a computer equipped with appropriate software. The system has 10 channels of spectral bandwidth 16 nm, a useful spectral response from 350 nm to 1 μm with a high signal-to-noise ratio, signal sampling rates from 20 MHz to 2 kHz and 8 kbyte of local memory for each channel.

  17. Computational Model of a Biomass Driven Absorption Refrigeration System

    Directory of Open Access Journals (Sweden)

    Munyeowaji Mbikan

    2017-02-01

    Full Text Available The impact of vapour compression refrigeration is the main push for scientists to find an alternative sustainable technology. Vapour absorption is an ideal technology which makes use of waste heat or renewable heat, such as biomass, to drive absorption chillers from medium to large applications. In this paper, the aim was to investigate the feasibility of a biomass driven aqua-ammonia absorption system. An estimation of the solid biomass fuel quantity required to provide heat for the operation of a vapour absorption refrigeration cycle (VARC is presented; the quantity of biomass required depends on the fuel density and the efficiency of the combustion and heat transfer systems. A single-stage aqua-ammonia refrigeration system analysis routine was developed to evaluate the system performance and ascertain the rate of energy transfer required to operate the system, and hence, the biomass quantity needed. In conclusion, this study demonstrated the results of the performance of a computational model of an aqua-ammonia system under a range of parameters. The model showed good agreement with published experimental data.

  18. Selective absorption of water from different oil–water emulsions with ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 30; Issue 4. Selective absorption of water from different oil–water emulsions with Psy-cl-poly(AAm) synthesized using irradiation copolymerization method. B S Kaith Kiran Kumar. Polymers Volume 30 Issue 4 August 2007 pp 387-391 ...

  19. Optical absorption spectra of linear and cyclic thiophenes--selection rules manifestation

    International Nuclear Information System (INIS)

    Bednarz, Mariusz; Reineker, Peter; Mena-Osteritz, Elena; Baeuerle, Peter

    2004-01-01

    We theoretically study the size-dependent relation between absorption spectra of thiophene-based oligomers and the corresponding cyclothiophenes. In our approach based on a Frenkel exciton Hamiltonian, we demonstrate that the geometry and selection rules determine the observed relations between the spectra

  20. COMPREHENSIVE ANALYSIS OF BIOLOGICALLY RELEVANT ARSENICALS BY PH-SELECTIVE HYDRIDE GENERATION-ATOMIC ABSORPTION SPECTROMETRY

    Science.gov (United States)

    A method based on pH-selective generation and separation of arsines is commonly used for analysis of inorganic, methylated, and dimethylated trivalent and pentavalent arsenicals by hydride generation-atomic absorption spectrometry (HG-AAS). We have optimized this method to pe...

  1. Thermodynamic simulation of ammonia-water absorption refrigeration system

    Directory of Open Access Journals (Sweden)

    Sathyabhama A.

    2008-01-01

    Full Text Available The ammonia-water absorption refrigeration system is attracting increasing research interests, since the system can be powered by waste thermal energy, thus reducing demand on electricity supply. The development of this technology demands reliable and effective system simulations. In this work, a thermodynamic simulation of the cycle is carried out to investigate the effects of different operating variables on the performance of the cycle. A computer program in C language is written for the performance analysis of the cycle.

  2. Simulation of solar-powered absorption cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Atmaca, I.; Yigit, A. [Uludag Univ., Bursa (Turkey). Dept. of Mechanical Engineering

    2003-07-01

    With developing technology and the rapid increase in world population, the demand for energy is ever increasing. Conventional energy will not be enough to meet the continuously increasing need for energy in the future. In this case, renewable energy sources will become important. Solar energy is a very important energy source because of its advantages. Instead of a compressor system, which uses electricity, an absorption cooling system, using renewable energy and kinds of waste heat energy, may be used for cooling. In this study, a solar-powered, single stage, absorption cooling system, using a water-lithium bromide solution, is simulated. A modular computer program has been developed for the absorption system to simulate various cycle configurations and solar energy parameters for Antalya, Turkey. So, the effects of hot water inlet temperatures on the coefficient of performance (COP) and the surface area of the absorption cooling components are studied. In addition, reference temperatures which are the minimum allowable hot water inlet temperatures are determined and their effect on the fraction of the total load met by non-purchased energy (FNP) and the coefficient of performance are researched. Also, the effects of the collector type and storage tank mass are investigated in detail. (author)

  3. Backscatter absorption gas imaging systems and light sources therefore

    Science.gov (United States)

    Kulp, Thomas Jan [Livermore, CA; Kliner, Dahv A. V. [San Ramon, CA; Sommers, Ricky [Oakley, CA; Goers, Uta-Barbara [Campbell, NY; Armstrong, Karla M [Livermore, CA

    2006-12-19

    The location of gases that are not visible to the unaided human eye can be determined using tuned light sources that spectroscopically probe the gases and cameras that can provide images corresponding to the absorption of the gases. The present invention is a light source for a backscatter absorption gas imaging (BAGI) system, and a light source incorporating the light source, that can be used to remotely detect and produce images of "invisible" gases. The inventive light source has a light producing element, an optical amplifier, and an optical parametric oscillator to generate wavelength tunable light in the IR. By using a multi-mode light source and an amplifier that operates using 915 nm pump sources, the power consumption of the light source is reduced to a level that can be operated by batteries for long periods of time. In addition, the light source is tunable over the absorption bands of many hydrocarbons, making it useful for detecting hazardous gases.

  4. Lack of dust in quasar absorption line systems

    International Nuclear Information System (INIS)

    Jura, M.

    1977-01-01

    It is stated that the origin of absorption line systems in quasars is still uncertain. Most such systems apparently have atomic hydrogen column densities of the order of 10 19 /cm 2 , but at least two quasars, 1331 + 170 and PHL957, have such strong Lyman α absorption lines that atomic hydrogen column densities of the order of 10 21 /cm 2 are indicated. It should be possible to observe the dust produced 2,200 A extinction feature as it is red shifted into the visible, and to determine whether absorption line systems are produced in spiral galaxies where the dust content is similar to that in the interstellar medium. It has been argued that the emission line regions of quasars generally lack dust and that towards PHL957 the 2,200 A feature is absent. The present author argues that dust similar to that found in the interstellar medium is not found towards the quasars 1331 + 170 and PHL957. This could explain why H 2 is not found towards PHL957, and it indicates that the absorption line systems in quasars are not produced in spiral galaxies similar to our own. It seems from the analysis presented that the dust-to-gas ratio towards 1331 + 170 is at least a factor of 20 less than in the interstellar medium, and there is no reason to suppose that this lack of dust results from a lack of metals It is concluded that there seems to be a lack of normal dust towards PHL957 by at least a factor of two; and that the absorption region towards 1331 + 170 and probably the region towards PHL957 are lacking dust similar to that in our own galaxy. This can explain the lack of H 2 in these systems. (U.K.)

  5. Use of a parallel artificial membrane system to evaluate passive absorption and elimination in small fish.

    Science.gov (United States)

    Kwon, Jung-Hwan; Katz, Lynn E; Liljestrand, Howard M

    2006-12-01

    A parallel artificial lipid membrane system was developed to mimic passive mass transfer of hydrophobic organic chemicals in fish. In this physical model system, a membrane filter-supported lipid bilayer separates two aqueous phases that represent the external and internal aqueous environments of fish. To predict bioconcentration kinetics in small fish with this system, literature absorption and elimination rates were analyzed with an allometric diffusion model to quantify the mass transfer resistances in the aqueous and lipid phases of fish. The effect of the aqueous phase mass transfer resistance was controlled by adjusting stirring intensity to mimic bioconcentration rates in small fish. Twenty-three simple aromatic hydrocarbons were chosen as model compounds for purposes of evaluation. For most of the selected chemicals, literature absorption/elimination rates fall into the range predicted from measured membrane permeabilities and elimination rates of the selected chemicals determined by the diffusion model system.

  6. Performance modelling and simulation of an absorption solar cooling system for Malaysia

    International Nuclear Information System (INIS)

    Assilzadeh, F.; Ali, Y.; Kamaruzzaman Sopian

    2006-01-01

    Solar radiation contains huge amounts of energy and is required for almost all the natural processes on earth. Solar-powered air-conditioning has many advantages when compared to normal electricity system. This paper presents a solar cooling system that has been designed for Malaysia and other tropical regions using evacuated tube solar collector and LiBr absorption system. A modelling and simulation of absorption solar cooling system is modeled in Transient System Simulation (TRNSYS) environment. The typical meteorological year file containing the weather parameters is used to simulate the system. Then a system optimization is carried out in order to select the appropriate type of collector, the optimum size of storage tank, the optimum collector slope and area and the optimum thermostat setting of the auxiliary boiler

  7. Material selection for elastic energy absorption in origami-inspired compliant corrugations

    International Nuclear Information System (INIS)

    Tolman, Sean S; Delimont, Isaac L; Howell, Larry L; Fullwood, David T

    2014-01-01

    Elastic absorption of kinetic energy and distribution of impact forces are required in many applications. Recent attention to the potential for using origami in engineering may provide new methods for energy absorption and force distribution. A three-stage strategy is presented for selecting materials for such origami-inspired designs that can deform to achieve a desired motion without yielding, absorb elastic strain energy, and be lightweight or cost effective. Two material indices are derived to meet these requirements based on compliant mechanism theory. Finite element analysis is used to investigate the effects of the material stiffness in the Miura-ori tessellation on its energy absorption and force distribution characteristics compared with a triangular wave corrugation. An example is presented of how the method can be used to select a material for a general energy absorption application of the Miura-ori. Whereas the focus of this study is the Miura-ori tessellation, the methods developed can be applied to other tessellated patterns used in energy absorbing or force distribution applications. (paper)

  8. Performance of a compact solar absorption cooling system

    International Nuclear Information System (INIS)

    Mulyanef; Kamaruzzaman Sopian

    2006-01-01

    This paper describes the performance of a compact solar absorption system. Purpose of compact solar is collector, generator and condenser in one unit. At present, two types of absorption cooling systems are marketed: the lithium bromide-water system and the ammonia-water system. In the lithium bromide-water system, water vapor is the refrigerant and ammonia water system where ammonia is the refrigerant. In addition, the ammonia-water system requires higher generator temperature 120 o C to 150 o C than a flat-plate solar collector can provide without special techniques. The lithium bromide-water system operates satisfactorily at a generator temperature of 75 o C to 100 o C, achievable by a flat-plate collector. The lithium bromide-water system also has a higher COP than the ammonia-water system. The disadvantage of the lithium bromide-water systems is that the evaporators cannot operate at temperature below 0 o C since the refrigerant is water. The Coefficient of Performance (COP) system is 0.62 and the concentration of LiBr-H 2 O is 50%

  9. Economic performance optimization of an absorption cooling system under uncertainty

    International Nuclear Information System (INIS)

    Gebreslassie, Berhane H.; Guillen-Gosalbez, Gonzalo; Jimenez, Laureano; Boer, Dieter

    2009-01-01

    Many of the strategies devised so far to address the optimization of energy systems are deterministic approaches that rely on estimated data. However, in real world applications there are many sources of uncertainty that introduce variability into the decision-making problem. Within this general context, we propose a novel approach to address the design of absorption cooling systems under uncertainty in the energy cost. As opposed to other approaches that optimize the expected performance of the system as a single objective, in our method the design task is formulated as a stochastic bi-criteria non-linear optimization problem that simultaneously accounts for the minimization of the expected total cost and the financial risk associated with the investment. The latter criterion is measured by the downside risk, which avoids the need to define binary variables thus improving the computational performance of the model. The capabilities of the proposed modeling framework and solution strategy are illustrated in a case study problem that addresses the design of a typical absorption cooling system. Numerical results demonstrate that the method presented allows to manage the risk level effectively by varying the area of the heat exchangers of the absorption cycle. Specifically, our strategy allows identifying the optimal values of the operating and design variables of the cycle that make it less sensitive to fluctuations in the energy price, thus improving its robustness in the face of uncertainty.

  10. The application of feature selection to the development of Gaussian process models for percutaneous absorption.

    Science.gov (United States)

    Lam, Lun Tak; Sun, Yi; Davey, Neil; Adams, Rod; Prapopoulou, Maria; Brown, Marc B; Moss, Gary P

    2010-06-01

    The aim was to employ Gaussian processes to assess mathematically the nature of a skin permeability dataset and to employ these methods, particularly feature selection, to determine the key physicochemical descriptors which exert the most significant influence on percutaneous absorption, and to compare such models with established existing models. Gaussian processes, including automatic relevance detection (GPRARD) methods, were employed to develop models of percutaneous absorption that identified key physicochemical descriptors of percutaneous absorption. Using MatLab software, the statistical performance of these models was compared with single linear networks (SLN) and quantitative structure-permeability relationships (QSPRs). Feature selection methods were used to examine in more detail the physicochemical parameters used in this study. A range of statistical measures to determine model quality were used. The inherently nonlinear nature of the skin data set was confirmed. The Gaussian process regression (GPR) methods yielded predictive models that offered statistically significant improvements over SLN and QSPR models with regard to predictivity (where the rank order was: GPR > SLN > QSPR). Feature selection analysis determined that the best GPR models were those that contained log P, melting point and the number of hydrogen bond donor groups as significant descriptors. Further statistical analysis also found that great synergy existed between certain parameters. It suggested that a number of the descriptors employed were effectively interchangeable, thus questioning the use of models where discrete variables are output, usually in the form of an equation. The use of a nonlinear GPR method produced models with significantly improved predictivity, compared with SLN or QSPR models. Feature selection methods were able to provide important mechanistic information. However, it was also shown that significant synergy existed between certain parameters, and as such it

  11. Natural selection on HFE in Asian populations contributes to enhanced non-heme iron absorption.

    Science.gov (United States)

    Ye, Kaixiong; Cao, Chang; Lin, Xu; O'Brien, Kimberly O; Gu, Zhenglong

    2015-06-10

    HFE, a major regulator of iron (Fe) homeostasis, has been suggested to be under positive selection in both European and Asian populations. While the genetic variant under selection in Europeans (a non-synonymous mutation, C282Y) has been relatively well-studied, the adaptive variant in Asians and its functional consequences are still unknown. Identifying the adaptive HFE variants in Asians will not only elucidate the evolutionary history and the genetic basis of population difference in Fe status, but also assist the future practice of genome-informed dietary recommendation. Using data from the International HapMap Project, we confirmed the signatures of positive selection on HFE in Asian populations and identified a candidate adaptive haplotype that is common in Asians (52.35-54.71%) but rare in Europeans (5.98%) and Africans (4.35%). The T allele at tag SNP rs9366637 (C/T) captured 95.8% of this Asian-common haplotype. A significantly reduced HFE expression was observed in individuals carrying T/T at rs9366637 compared to C/C and C/T, indicating a possible role of gene regulation in adaptation. We recruited 57 women of Asian descent and measured Fe absorption using stable isotopes in those homozygous at rs9366637. We observed a 22% higher absorption in women homozygous for the Asian-common haplotype (T/T) compared to the control genotype (C/C). Additionally, compared with a group of age-matched Caucasian women, Asian women exhibited significantly elevated Fe absorption. Our results indicate parallel adaptation of HFE gene in Europeans and Asians with different genetic variants. Moreover, natural selection on HFE may have contributed to elevated Fe absorption in Asians. This study regarding population differences in Fe homeostasis has significant medical impact as high Fe level has been linked to an increased disease risk of metabolic syndromes.

  12. Technique Selectively Represses Immune System

    Science.gov (United States)

    ... Research Matters December 3, 2012 Technique Selectively Represses Immune System Myelin (green) encases and protects nerve fibers (brown). A new technique prevents the immune system from attacking myelin in a mouse model of ...

  13. Highly Sensitive and Selective Uranium Detection in Natural Water Systems Using a Luminescent Mesoporous Metal-Organic Framework Equipped with Abundant Lewis Basic Sites: A Combined Batch, X-ray Absorption Spectroscopy, and First Principles Simulation Investigation.

    Science.gov (United States)

    Liu, Wei; Dai, Xing; Bai, Zhuanling; Wang, Yanlong; Yang, Zaixing; Zhang, Linjuan; Xu, Lin; Chen, Lanhua; Li, Yuxiang; Gui, Daxiang; Diwu, Juan; Wang, Jianqiang; Zhou, Ruhong; Chai, Zhifang; Wang, Shuao

    2017-04-04

    Uranium is not only a strategic resource for the nuclear industry but also a global contaminant with high toxicity. Although several strategies have been established for detecting uranyl ions in water, searching for new uranium sensor material with great sensitivity, selectivity, and stability remains a challenge. We introduce here a hydrolytically stable mesoporous terbium(III)-based MOF material compound 1, whose channels are as large as 27 Å × 23 Å and are equipped with abundant exposed Lewis basic sites, the luminescence intensity of which can be efficiently and selectively quenched by uranyl ions. The detection limit in deionized water reaches 0.9 μg/L, far below the maximum contamination standard of 30 μg/L in drinking water defined by the United States Environmental Protection Agency, making compound 1 currently the only MOF material that can achieve this goal. More importantly, this material exhibits great capability in detecting uranyl ions in natural water systems such as lake water and seawater with pH being adjusted to 4, where huge excesses of competing ions are present. The uranyl detection limits in Dushu Lake water and in seawater were calculated to be 14.0 and 3.5 μg/L, respectively. This great detection capability originates from the selective binding of uranyl ions onto the Lewis basic sites of the MOF material, as demonstrated by synchrotron radiation extended X-ray adsorption fine structure, X-ray adsorption near edge structure, and first principles calculations, further leading to an effective energy transfer between the uranyl ions and the MOF skeleton.

  14. Absorption in multiple scattering systems of coated spheres: design applications

    International Nuclear Information System (INIS)

    Stout, Brian; Andraud, Christine; Stout, Sophie; Lafait, Jacques

    2003-01-01

    We illustrate the utility of some recently derived transfer matrix methods for electromagnetic scattering calculations in systems composed of coated spherical scatterers. Any of the spherical coatings, cores, or host media may be composed of absorbing materials. Our formulae permit the calculation of local absorption in either orientation fixed or orientation averaged situations. We introduce methods for estimating the macroscopic transport properties of such media, and show how our scattering calculations can permit 'design' optimization of macroscopic properties

  15. β Absorption dust concentration monitor system based on the PLC

    International Nuclear Information System (INIS)

    Lian Dexing; Zhou Xiuliang; Liu Liyan; Li Zonglun; Cao Guanghui; Mao Wanchong

    2011-01-01

    To provide an on-line automatic system for dust concentration monitor is the purpose of this design.The system based on β-ray-absorption-method,employing PLC (Programmable Logic Controller) control technology, is presented. The user input parameter setup,the data acquisition and processing, and the communication with computer can be effectively regulated using the advanced PLC control technology. It has the features of high reliability, easy operation and easy maintenance, and the ability to monitor remotely. Measurement range: 0.1-1500 mg/m 3 , Accuracy: ±9%. The structure,working principle, electric circuit and software development of the system are introduced in detail. (authors)

  16. Selected System Models

    Science.gov (United States)

    Schmidt-Eisenlohr, F.; Puñal, O.; Klagges, K.; Kirsche, M.

    Apart from the general issue of modeling the channel, the PHY and the MAC of wireless networks, there are specific modeling assumptions that are considered for different systems. In this chapter we consider three specific wireless standards and highlight modeling options for them. These are IEEE 802.11 (as example for wireless local area networks), IEEE 802.16 (as example for wireless metropolitan networks) and IEEE 802.15 (as example for body area networks). Each section on these three systems discusses also at the end a set of model implementations that are available today.

  17. Selection of the optimal combination of water vapor absorption lines for detection of temperature in combustion zones of mixing supersonic gas flows by diode laser absorption spectrometry

    International Nuclear Information System (INIS)

    Mironenko, V.R.; Kuritsyn, Yu.A.; Bolshov, M.A.; Liger, V.V.

    2017-01-01

    Determination of a gas medium temperature by diode laser absorption spectrometry (DLAS) is based on the measurement of integral intensities of the absorption lines of a test molecule (generally water vapor molecule). In case of local thermodynamic equilibrium temperature is inferred from the ratio of the integral intensities of two lines with different low energy levels. For the total gas pressure above 1 atm the absorption lines are broadened and one cannot find isolated well resolved water vapor absorption lines within relatively narrow spectral interval of fast diode laser (DL) tuning range (about 3 cm"−"1). For diagnostics of a gas object in the case of high temperature and pressure DLAS technique can be realized with two diode lasers working in different spectral regions with strong absorption lines. In such situation the criteria of the optimal line selection differs significantly from the case of narrow lines. These criteria are discussed in our work. The software for selection the optimal spectral regions using the HITRAN-2012 and HITEMP data bases is developed. The program selects spectral regions of DL tuning, minimizing the error of temperature determination δT/T, basing on the attainable experimental error of line intensity measurement δS. Two combinations of optimal spectral regions were selected – (1.392 & 1.343 μm) and (1.392 & 1.339 μm). Different algorithms of experimental data processing are discussed.

  18. Dependence of the solar absorptance of selective absorber coatings on the angle of incidence

    Energy Technology Data Exchange (ETDEWEB)

    Reed, K A

    1977-01-01

    The directional solar absorptances ..cap alpha../sub s/(theta) of samples of a number of selective absorber coatings have been determined. The spectral directional hemispherical reflectances plambda(theta;2..pi..) of each sample was measured over the wavelength range 0.3..mu.. to 2.5..mu.. at angles of incidence theta between 10/sup 0/ and 80/sup 0/. The quantity (1-plambda(theta;2..pi..)) was convoluted over an AM2 solar spectrum to obtain ..cap alpha../sub s/(theta) at each angle of incidence. The solar absorptance at near normal incidence varied from sample to sample and from coating to coating, as expected, given the present state of the art. All the absorptances show similar angular dependences, however. When normalized to unity at normal incidence, the data nearly describe a single curve, for which a power series in theta was found. For comparison, the solar absorptance was also determined for freshly prepared lamp black.

  19. Monitoring and analysis of an absorption air-conditioning system

    Energy Technology Data Exchange (ETDEWEB)

    Perez de Vinaspre, M.; Bourouis, M.; Coronas, A. [Centro de Innovacion Tecnologica en Revalorizacion Energetica y Refrigeracion, Tarragona (Spain); Garcia, A.; Soto, V.; Pinazo, J.M. [E.T.S. Ingenieros Industriales, Valencia (Spain)

    2004-09-01

    In the last few years, high-energy consumption due to air-conditioning has led to a growing interest in the efficient use of energy in buildings. Although simulation programs have always been the main tools for analyzing energy in buildings, the reliability of their results is often compromised by a lack of certainty to reflect real conditions. The aim of this work is to monitorize and analyze the thermal behavior of an absorption-based air-conditioning installation of a university building in Tarragona, Spain. The existing monitoring system of the installation has been improved by implementing additional sensors and flow meters. The data has been stored during summer 2002 and used to assess the energy balance of the air-conditioning installation and the operational regime of the absorption chiller. [Author].

  20. Differential Optical-absorption Spectroscopy (doas) System For Urban Atmospheric-pollution Monitoring

    OpenAIRE

    Edner, H; Ragnarson, P; Spannare, S; Svanberg, Sune

    1993-01-01

    We describe a fully computer-controlled differential optical absorption spectroscopy system for atmospheric air pollution monitoring. A receiving optical telescope can sequentially tune in to light beams from a number of distant high-pressure Xe lamp light sources to cover the area of a medium-sized city. A beam-finding servosystem and automatic gain control permit unattended long-time monitoring. Using an astronomical code, we can also search and track celestial sources. Selected wavelength ...

  1. Energy and exergy analyses of the diffusion absorption refrigeration system

    International Nuclear Information System (INIS)

    Yıldız, Abdullah; Ersöz, Mustafa Ali

    2013-01-01

    This paper describes the thermodynamic analyses of a DAR (diffusion absorption refrigeration) cycle. The experimental apparatus is set up to an ammonia–water DAR cycle with helium as the auxiliary inert gas. A thermodynamic model including mass, energy and exergy balance equations are presented for each component of the DAR cycle and this model is then validated by comparison with experimental data. In the thermodynamic analyses, energy and exergy losses for each component of the system are quantified and illustrated. The systems' energy and exergy losses and efficiencies are investigated. The highest energy and exergy losses occur in the solution heat exchanger. The highest energy losses in the experimental and theoretical analyses are found 25.7090 W and 25.4788 W respectively, whereas those losses as to exergy are calculated 13.7933 W and 13.9976 W. Although the values of energy efficiencies obtained from both the model and experimental studies are calculated as 0.1858, those values, in terms of exergy efficiencies are found 0.0260 and 0.0356. - Highlights: • The diffusion absorption refrigerator system is designed manufactured and tested. • The energy and exergy analyses of the system are presented theoretically and experimentally. • The energy and exergy losses are investigated for each component of the system. • The highest energy and exergy losses occur in the solution heat exchanger. • The energy and the exergy performances are also calculated

  2. Selecting a Cable System Operator.

    Science.gov (United States)

    Cable Television Information Center, Washington, DC.

    Intended to assist franchising authorities with the process of selecting a cable television system operator from franchise applicants, this document provides a framework for analysis of individual applications. Section 1 deals with various methods which can be used to select an operator. The next section covers the application form, the vehicle a…

  3. Selecting practice management information systems.

    Science.gov (United States)

    Worley, R; Ciotti, V

    1997-01-01

    Despite enormous advances in information systems, the process by which most medical practices select them has remained virtually unchanged for decades: the request for proposal (RFP). Unfortunately, vendors have learned ways to minimize the value of RFP checklists to where purchasers now learn little about the system functionality. The authors describe a selection methodology that replaces the RFP with scored demos, reviews of vendor user manuals and mathematically structured reference checking. In a recent selection process at a major medical center, these techniques yielded greater user buy-in and favorable contract terms as well.

  4. Airborne differential absorption lidar system for water vapor investigations

    Science.gov (United States)

    Browell, E. V.; Carter, A. F.; Wilkerson, T. D.

    1981-01-01

    Range-resolved water vapor measurements using the differential-absorption lidar (DIAL) technique is described in detail. The system uses two independently tunable optically pumped lasers operating in the near infrared with laser pulses of less than 100 microseconds separation, to minimize concentration errors caused by atmospheric scattering. Water vapor concentration profiles are calculated for each measurement by a minicomputer, in real time. The work is needed in the study of atmospheric motion and thermodynamics as well as in forestry and agriculture problems.

  5. Absorption of selected radionuclides. Analysis of a literature study. Resorption ausgewaehlter Radionuklide. Analyse einer Literaturstudie

    Energy Technology Data Exchange (ETDEWEB)

    Roedler, H D; Kraus, H M

    1979-12-01

    In October 1978, the Institut fuer Energie- und Umweltforschung Heidelberg e.V. published a contribution to part 26 of the model study of radio-ecology at Biblis under the title 'Estimation of the absorption of radionuclides from the gastrointestinal tract in the blood'. Using the example of this contribution, a critical analysis is made to show how a selection of the information contained in various scientific publications and other items of literature can give uncritical readers the impression that all statements made are scientifically well founded.

  6. Selection Method for COTS Systems

    DEFF Research Database (Denmark)

    Hedman, Jonas; Andersson, Bo

    2014-01-01

    feature behind the method is that improved understanding of organizational ‘ends’ or goals should govern the selection of a COTS system. This can also be expressed as a match or fit between ‘ends’ (e.g. improved organizational effectiveness) and ‘means’ (e.g. implementing COTS systems). This way...

  7. Decision support system to select cover systems

    International Nuclear Information System (INIS)

    Bostick, K.V.

    1995-01-01

    The objective of this technology is to provide risk managers with a defensible, objective way to select capping alternatives for remediating radioactive and mixed waste landfills. The process of selecting containment cover technologies for mixed waste landfills requires consideration of many complex and interrelated technical, regulatory, and economic issues. A Decision Support System (DSS) is needed to integrate the knowledge of experts from scientific, engineering, and management disciplines to help in selecting the best capping practice for the site

  8. Industrial trigeneration using ammonia-water absorption refrigeration systems (AAR)

    International Nuclear Information System (INIS)

    Colonna, Piero; Gabrielli, Sandro

    2003-01-01

    In many industrial processes there is a simultaneous need for electric power and refrigeration at low temperatures. Examples are in the food and chemical industries. Nowadays the increase in fuel prices and the ecological implications are giving an impulse to energy technologies that better exploit the primary energy source and integrated production of utilities should be considered when designing a new production plant. The number of so-called trigeneration systems installations (electric generator and absorption refrigeration plant) is increasing. If low temperature refrigeration is needed (from 0 to -40 deg. C), ammonia-water absorption refrigeration plants can be coupled to internal combustion engines or turbogenerators. A thermodynamic system study of trigeneration configurations using a commercial software integrated with specifically designed modules is presented. The study analyzes and compares heat recovery from the primary mover at different temperature levels. In the last section a simplified economic assessment that takes into account disparate prices in European countries compares conventional electric energy supply from the grid and optimized trigeneration plants in one test case (10 MW electric power, 7000 h/year)

  9. New thermodynamical systems. Alternative of compression-absorption; Nouveaux systemes thermodynamiques. Alternative de la compression-absorption

    Energy Technology Data Exchange (ETDEWEB)

    Feidt, M.; Brunin, O.; Lottin, O.; Vidal, J.F. [Universite Henri Poincare Nancy, 54 - Vandoeuvre-les-Nancy (France); Hivet, B. [Electricite de France, 77 - Moret sur Loing (France)

    1996-12-31

    This paper describes a 5 years joint research work carried out by Electricite de France (EdF) and the ESPE group of the LEMTA on compression-absorption heat pumps. It shows how a thermodynamical model of machinery, completed with precise exchanger-reactor models, allows to simulate and dimension (and eventually optimize) the system. A small power prototype has been tested and the first results are analyzed with the help of the models. A real scale experiment in industrial sites is expected in the future. (J.S.) 20 refs.

  10. Selective Reversible Absorption of the Industrial Off-Gas Components CO2 and NOx by Ionic Liquids

    DEFF Research Database (Denmark)

    Kaas-Larsen, Peter Kjartan; Thomassen, P.; Schill, Leonhard

    2016-01-01

    Ionic liquids are promising new materials for climate and pollution control by selective absorption of CO2 and NOx in industrial off-gases. In addition practical cleaning of industrial off gases seems to be attractive by use of ionic liquids distributed on the surface of porous, high surface area...... carriers in the form of so-called Supported Ionic Liquid Phase (SILP) materials. The potential of selected ionic liquids for absorption of CO2 and NOx are demonstrated and the possible interference of other gases influencing the stability and absorption capacity of the ionic liquids are investigated...

  11. System for illuminating a region for isotopically selective photoexcitation

    International Nuclear Information System (INIS)

    Debaryshe, P.G.; Janes, G.S.; Levy, R.H.; Lindenmeier, C.W.

    1979-01-01

    A method is described to improve laser beam utilization in isotope separation techniques (using laser induced isotopically selective photoexcitation) by increasing the probability of photon absorption without extreme beam propagation lengths. For this purpose an optical reflection system has been designed for illuminating substantially all of three-dimensional space of a transversely flowing vapor with multiple traversals of a beam of radiation. (UK)

  12. Selection Process of ERP Systems

    OpenAIRE

    Molnár, Bálint; Szabó, Gyula; Benczúr, András

    2013-01-01

    Background: The application and introduction of ERP systems have become a central issue for management and operation of enterprises. The competition on market enforces the improvement and optimization of business processes of enterprises to increase their efficiency, effectiveness, and to manage better the resources outside the company. The primary task of ERP systems is to achieve the before-mentioned objectives. Objective: The selection of a particular ERP system has a decisive effect on th...

  13. A low-cost vaporization-atomization system for atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Bruhn F, C.G.; Ambiado V, F.; Woerner V, R.

    1990-01-01

    A low-cost vaporization-atomization system for atomic absorption spectrometry is developed as an alternative to the use of a graphite furnace in electrothermal atomic absorption spectrometry. (Author)

  14. The redshift number density evolution of Mg II absorption systems

    International Nuclear Information System (INIS)

    Chen Zhi-Fu

    2013-01-01

    We make use of the recent large sample of 17 042 Mg II absorption systems from Quider et al. to analyze the evolution of the redshift number density. Regardless of the strength of the absorption line, we find that the evolution of the redshift number density can be clearly distinguished into three different phases. In the intermediate redshift epoch (0.6 ≲ z ≲ 1.6), the evolution of the redshift number density is consistent with the non-evolution curve, however, the non-evolution curve over-predicts the values of the redshift number density in the early (z ≲ 0.6) and late (z ≳ 1.6) epochs. Based on the invariant cross-section of the absorber, the lack of evolution in the redshift number density compared to the non-evolution curve implies the galaxy number density does not evolve during the middle epoch. The flat evolution of the redshift number density tends to correspond to a shallow evolution in the galaxy merger rate during the late epoch, and the steep decrease of the redshift number density might be ascribed to the small mass of halos during the early epoch.

  15. OBSERVATIONS OF Mg II ABSORPTION NEAR z ∼ 1 GALAXIES SELECTED FROM THE DEEP2 REDSHIFT SURVEY

    International Nuclear Information System (INIS)

    Lovegrove, Elizabeth; Simcoe, Robert A.

    2011-01-01

    We study the frequency of Mg II absorption in the outer halos of galaxies at z = 0.6-1.4 (with median z = 0.87), using new spectra obtained of 10 background quasars with galaxy impact parameters of b r = 0.15-1.0 A, though not all absorbers correlate with DEEP galaxies. We find five unique absorbers within Δv = 500 km s -1 and b r > 1.0 A, consistent with other samples of galaxy-selected Mg II systems. We speculate that Mg II systems with 0.3 r r are more likely to reflect the more recent star-forming history of their associated galaxies.

  16. Production Systems and Supplier Selection

    DEFF Research Database (Denmark)

    Pedraza-Acosta, Isabel; Pilkington, Alan; Barnes, David

    2016-01-01

    strategic stamping suppliers. Findings: Our contribution is the multi-phased production and product innovation process. This is an advance from traditional supplier selection and also an extension of ideas of supplier-located product development as it includes production system development, and complements...

  17. Wideband RCS Reduction of Microstrip Array Antenna Based on Absorptive Frequency Selective Surface and Microstrip Resonators

    Directory of Open Access Journals (Sweden)

    Jingjing Xue

    2017-01-01

    Full Text Available An approach for wideband radar cross section (RCS reduction of a microstrip array antenna is presented and discussed. The scheme is based on the microstrip resonators and absorptive frequency selective surface (AFSS with a wideband absorptive property over the low band 1.9–7.5 GHz and a transmission characteristic at high frequency 11.05 GHz. The AFSS is designed to realize the out-of-band RCS reduction and preserve the radiation performance simultaneously, and it is placed above the antenna with the operating frequency of 11.05 GHz. Moreover, the microstrip resonators are loaded to obtain the in-band RCS reduction. As a result, a significant RCS reduction from 1.5 GHz to 13 GHz for both types of polarization has been accomplished. Compared with the reference antenna, the simulated results exhibit that the monostatic RCS of the proposed array antenna in x- and y-polarization can be reduced as much as 17.6 dB and 21.5 dB, respectively. And the measured results agree well with the simulated ones.

  18. Understanding Absorptive Capacities is an "Innovation Systems" Context

    DEFF Research Database (Denmark)

    Narula, Rajneesh

    2004-01-01

    This paper seeks to broaden our understanding of the concept underlying absorptive capacity atthe macro -level, paying particular attention to the growth and development perspectives. Weprovide definitions of absorptive and technological capacity, external technology flows,productivity growth....... We also undertake to explain how the nature ofabsorptive capacity changes with stages of economic development, and the importance of thedifferent aspects of absorptive capability at different stages. The relationship is not a linear one:the benefits that accrue from marginal increases in absorptive...... capability change over time.Finally, we provide a tentative and preliminary conceptual argument of how the different stagesof absorptive capacity are related to productivity growth, economic growth and employmentcreation.Key words: New economy, absorptive capacity, knowledge...

  19. Cooling performance and energy saving of a compression-absorption refrigeration system assisted by geothermal energy

    International Nuclear Information System (INIS)

    Kairouani, L.; Nehdi, E.

    2006-01-01

    The objectives of this paper are to develop a novel combined refrigeration system, and to discuss the thermodynamic analysis of the cycle and the feasibility of its practical development. The aim of this work was to study the possibility of using geothermal energy to supply vapour absorption system cascaded with conventional compression system. Three working fluids (R717, R22, and R134a) are selected for the conventional compression system and the ammonia-water pair for the absorption system. The geothermal temperature source in the range 343-349 K supplies a generator operating at 335 K. Results show that the COP of a combined system is significantly higher than that of a single stage refrigeration system. It is found that the COP can be improved by 37-54%, compared with the conventional cycle, under the same operating conditions, that is an evaporation temperature at 263 K and a condensation temperature of 308 K. For industrial refrigeration, the proposed system constitutes an alternative solution for reducing energy consumption and greenhouse gas emissions

  20. Rapidly reconfigurable slow-light system based on off-resonant Raman absorption

    International Nuclear Information System (INIS)

    Vudyasetu, Praveen K.; Howell, John C.; Camacho, Ryan M.

    2010-01-01

    We present a slow-light system based on dual Raman absorption resonances in warm rubidium vapor. Each Raman absorption resonance is produced by a control beam in an off-resonant Λ system. This system combines all optical control of the Raman absorption and the low-dispersion broadening properties of the double Lorentzian absorption slow light. The bandwidth, group delay, and central frequency of the slow-light system can all be tuned dynamically by changing the properties of the control beam. We demonstrate multiple pulse delays with low distortion and show that such a system has fast switching dynamics and thus fast reconfiguration rates.

  1. Water absorption length measurement with the ANTARES optical beacon system

    International Nuclear Information System (INIS)

    Yepes-Ramirez, Harold

    2011-01-01

    ANTARES is a neutrino telescope located in the Mediterranean Sea with the aim of detecting high energy neutrinos of extra-terrestrial origin. It consists of a three dimensional array on 12 detection lines of photomultiplier tubes (PMTs) able to detect the Cherenkov light induced by muons produced in the interaction of neutrinos with the surrounding water and seabed. To reach the best angular resolution, good time and positioning calibrations are required. The propagation of Cherenkov photons strongly depends on the optical properties of the sea water, which has an impact on the reconstruction efficiency. The determination of the optical parameters, as the absorption and scattering lengths, is crucial to calculate properly the effective area and the angular resolution of the detector. The ANTARES optical beacon system consists of pulsed and fast, well controlled light sources distributed throughout the detector to carry out in situ the relative time calibration of the detector components. In this contribution we show some results on the sea water optical properties and their stability measured with the optical beacon system.

  2. Depth-selective X-ray absorption spectroscopy by detection of energy-loss Auger electrons

    Energy Technology Data Exchange (ETDEWEB)

    Isomura, Noritake, E-mail: isomura@mosk.tytlabs.co.jp [Toyota Central R& D Labs., Inc., 41-1 Yokomichi, Nagakute, Aichi 480-1192 (Japan); Soejima, Narumasa; Iwasaki, Shiro [Toyota Central R& D Labs., Inc., 41-1 Yokomichi, Nagakute, Aichi 480-1192 (Japan); Nomoto, Toyokazu; Murai, Takaaki [Aichi Synchrotron Radiation Center (AichiSR), 250-3 Minamiyamaguchi-cho, Seto, Aichi 489-0965 (Japan); Kimoto, Yasuji [Toyota Central R& D Labs., Inc., 41-1 Yokomichi, Nagakute, Aichi 480-1192 (Japan)

    2015-11-15

    Graphical abstract: - Highlights: • A unique XAS method is proposed for depth profiling of chemical states. • PEY mode detecting energy-loss electrons enables a variation in the probe depth. • Si K-edge XAS spectra of the Si{sub 3}N{sub 4}/SiO{sub 2}/Si multilayer films have been investigated. • Deeper information was obtained in the spectra measured at larger energy loss. • Probe depth could be changed by the selection of the energy of detected electrons. - Abstract: A unique X-ray absorption spectroscopy (XAS) method is proposed for depth profiling of chemical states in material surfaces. Partial electron yield mode detecting energy-loss Auger electrons, called the inelastic electron yield (IEY) mode, enables a variation in the probe depth. As an example, Si K-edge XAS spectra for a well-defined multilayer sample (Si{sub 3}N{sub 4}/SiO{sub 2}/Si) have been investigated using this method at various kinetic energies. We found that the peaks assigned to the layers from the top layer to the substrate appeared in the spectra in the order of increasing energy loss relative to the Auger electrons. Thus, the probe depth can be changed by the selection of the kinetic energy of the energy loss electrons in IEY-XAS.

  3. Depth-selective X-ray absorption spectroscopy by detection of energy-loss Auger electrons

    International Nuclear Information System (INIS)

    Isomura, Noritake; Soejima, Narumasa; Iwasaki, Shiro; Nomoto, Toyokazu; Murai, Takaaki; Kimoto, Yasuji

    2015-01-01

    Graphical abstract: - Highlights: • A unique XAS method is proposed for depth profiling of chemical states. • PEY mode detecting energy-loss electrons enables a variation in the probe depth. • Si K-edge XAS spectra of the Si_3N_4/SiO_2/Si multilayer films have been investigated. • Deeper information was obtained in the spectra measured at larger energy loss. • Probe depth could be changed by the selection of the energy of detected electrons. - Abstract: A unique X-ray absorption spectroscopy (XAS) method is proposed for depth profiling of chemical states in material surfaces. Partial electron yield mode detecting energy-loss Auger electrons, called the inelastic electron yield (IEY) mode, enables a variation in the probe depth. As an example, Si K-edge XAS spectra for a well-defined multilayer sample (Si_3N_4/SiO_2/Si) have been investigated using this method at various kinetic energies. We found that the peaks assigned to the layers from the top layer to the substrate appeared in the spectra in the order of increasing energy loss relative to the Auger electrons. Thus, the probe depth can be changed by the selection of the kinetic energy of the energy loss electrons in IEY-XAS.

  4. [Wavelength Selection in Hemolytic Evaluation Systems with Spectrophotometry Detection].

    Science.gov (United States)

    Zhang, Hong; Su, Baochang; Ye, Xunda; Luo, Man

    2016-04-01

    Spectrophotometry is a simple hemolytic evaluation method commonly used in new drugs,biomedical materials and blood products.It is for the quantitative analysis of the characteristic absorption peaks of hemoglobin.Therefore,it is essential to select the correct detection wavelength when the evaluation system has influences on the conformation of hemoglobin.Based on the study of changes in the characteristic peaks over time of the hemolysis supernatant in four systems,namely,cell culture medium,phosphate buffered saline(PBS),physiological saline and banked blood preservation solution,using continuous wavelength scanning,the selections of detection wavelength were proposed as follows.In the cell culture medium system,the wavelength of 415 nm should be selected within 4h;,near 408 nm should be selected within 4~72h.In PBS system,within 4h,541 nm,577nm or 415 nm should be selected;4~72h,541 nm,577nm or near 406 nm should be selected.In physiological saline system,within 4h,414 nm should be selected;4~72h,near 405 nm should be selected;within 12 h,541nm or 577 nm could also be selected.In banked blood preservation solution system,within 72 h,415nm,540 nm or 576 nm should be selected.

  5. Absorption of UV-B to blue light radiation by leaf cuticles of selected crop plants

    International Nuclear Information System (INIS)

    Baur, P.; Stulle, K.; Schönherr, J.; Uhlig, B.

    1998-01-01

    Plants have protective pigments absorbing destructive shortwave radiation. These pigments have been found in the epidermis and mesophyll of leaves. We studied the absorption characteristics of the leaf cuticle, the outermost part of the epidermis that is directly exposed to radiation. Adaxial leaf cuticles of apple, pear, sour cherry, strawberry, cauliflower, sugarbeet, and 13 other plant species were tested. The UV-B absorption was highest in Citrus aurantium and Citrus maxima (<3 % transmittance) and lowest in sugarbeet and peach (>64 % transmittance). The absorption maxima are at wavelenghts below 320 nm. Significant absorption was also determined at 500 nm, which correlated with cuticle thickness of the plant species (r(2)=0.72). The absorption in the range of 250 to 350 nm is caused by pigments with a high extinction coefficient. This absorption is species dependent and the patterns were designated to three different types. The highest absorption was found in evergreen species. The extraction of cuticular waxes had little effect on absorption. The specific absorption of shortwave radiation by plant cuticles is probably caused by pigments covalently bound to cut in. It is known for some plant species that cuticles can contain the phenolics p-coumaric acid, ferulic acid, and vanillic acid. Mixtures of these phenolics had spectra similar to cuticles. For most species absorption of shortwave radiation by the cuticle alone does not give complete protection

  6. Diode laser absorption spectroscopy for process control: Sensor system design methodology

    International Nuclear Information System (INIS)

    Berzins, L.V.; Anklam, T.M.; Chambers, F.; Galanti, S.; Haynam, C.A.; Worden, E.F.

    1995-03-01

    A laser absorption spectroscopy (LAS) system has been developed at Lawrence Livermore National Laboratory (LLNL) for process control. LAS has proven itself to be an accurate and reliable method to monitor both density and composition. In this paper the important features and components of an industrial LAS diagnostic are described. Application of this approach to vaporization processes requires careful selection of the species and transitions to be monitored The relative vapor pressure, hyperfine structure, isotopic frequency shifts, and electronic temperature all effect the selection of a particular transition. In this paper we describe the methodology for choosing the optimal transition or transitions. Coevaporation of a titanium-niobium alloy is used to illustrate the methodology. In a related paper, T.M. Anklam et al describe the application of this diagnostic to monitoring and controlling composition in a physical vapor deposition process of industrial interest

  7. Selective absorption pilot plant for decontamination of fuel reprocessing plant off-gas

    Energy Technology Data Exchange (ETDEWEB)

    Stephenson, M.J.; Eby, R.S.; Huffstetler, V.C.

    1977-10-01

    A fluorocarbon-based selective absorption process for removing krypton-85, carbon-14, and radon-222 from the off-gas of conventional light water and advanced reactor fuel reprocessing plants is being developed at the Oak Ridge Gaseous Diffusion Plant in conjunction with fuel recycle work at the Oak Ridge National Laboratory and at the Savannah River Laboratory. The process is characterized by an especially high tolerance for many other reprocessing plant off-gas components. This report presents detailed drawings and descriptions of the second generation development pilot plant as it has evolved after three years of operation. The test facility is designed on the basis of removing 99% of the feed gas krypton and 99.9% of the carbon and radon, and can handle a nominal 15 scfm (425 slm) of contaminated gas at pressures from 100 to 600 psig (7.0 to 42.2 kg/cm/sup 2/) and temperatures from minus 45 to plus 25/sup 0/F (-43 to -4/sup 0/C). Part of the development program is devoted to identifying flowsheet options and simplifications that lead to an even more economical and reliable process. Two of these applicative flowsheets are discussed.

  8. Selective Reversible Absorption of the Industrial Off-Gas Components CO2 and NOx by Ionic Liquids

    DEFF Research Database (Denmark)

    Kaas-Larsen, Peter Kjartan; Thomassen, Peter; Schill, Leonard

    2016-01-01

    Ionic liquids are promising new materials for climate and pollution control by selective absorption of CO2 and NOx in industrial off-gases. In addition pratical cleaning of industrial off gases seems to be attractive by use of ionic liquids distributed on the surface of porous, high surface area...

  9. A new active absorption system and its performance to linear and non-linear waves

    DEFF Research Database (Denmark)

    Andersen, Thomas Lykke; Clavero, M.; Frigaard, Peter Bak

    2016-01-01

    Highlights •An active absorption system for wavemakers has been developed. •The theory for flush mounted gauges has been extended to cover also small gaps. •The new system has been validated in a wave flume with wavemakers in both ends. •A generation and absorption procedure for highly non-linear...

  10. Photoacoustic Experimental System to Confirm Infrared Absorption Due to Greenhouse Gases

    Science.gov (United States)

    Kaneko, Fumitoshi; Monjushiro, Hideaki; Nishiyama, Masayoshi; Kasai, Toshio; Harris, Harold H.

    2010-01-01

    An experimental system for detecting infrared absorption using the photoacoustic (PA) effect is described. It is aimed for use at high-school level to illustrate the difference in infrared (IR) absorption among the gases contained in the atmosphere in connection with the greenhouse effect. The experimental system can be built with readily…

  11. CONCEPT OF AUTOMATIC CONTROL SYSTEM FOR IMPROVING THE EFFICIENCY OF THE ABSORPTION REFRIGERATING UNITS

    Directory of Open Access Journals (Sweden)

    O. Titlova

    2016-12-01

    Full Text Available The general concept of the automatic control systems constructing for increasing the efficiency of the artificial cold production process in the absorption refrigerating units is substantiated. The described automatic control systems provides necessary degree of the ammonia vapor purification from the water in all absorption refrigerating units modes and minimizes heat loss from the dephlegmator surface.

  12. The effect of age on systemic absorption and systemic disposition of bupivacaine after subarachnoid administration

    Energy Technology Data Exchange (ETDEWEB)

    Veering, B.T.; Burm, A.G.; Vletter, A.A.; van den Hoeven, R.A.; Spierdijk, J. (Leiden Univ. Hospital (Netherlands))

    1991-02-01

    In order to evaluate the role of the pharmacokinetics of the age-related changes in the clinical profile of spinal anesthesia with bupivacaine, we studied the influence of age on the systemic absorption and systemic disposition of bupivacaine after subarachnoid administration in 20 male patients (22-81 yr), ASA Physical Status 1 or 2, by a stable isotope method. After subarachnoid administration of 3 ml 0.5% bupivacaine in 8% glucose, a deuterium-labeled analog (13.4 mg) was administered intravenously. Blood samples were collected for 24 h. Plasma concentrations of unlabeled and deuterium-labeled bupivacaine were determined with a combination of gas chromatography and mass fragmentography. Biexponential functions were fitted to the plasma concentration-time data of the deuterium-labeled bupivacaine. The systemic absorption was evaluated by means of deconvolution. Mono- and biexponential functions were fitted to the data of fraction absorbed versus time. The maximal height of analgesia and the duration of analgesia at T12 increased with age (r = 0.715, P less than 0.001; r = 0.640, P less than 0.01, respectively). In 18 patients the systemic absorption of bupivacaine was best described by a biexponential equation. The half-life of the slow systemic absorption process (r = -0.478; P less than 0.05) and the mean absorption time (r = -0.551; P less than 0.02) decreased with age. The total plasma clearance decreased with age (r = -0.650, P less than 0.002), whereas the mean residence time and terminal half-life increased with age (r = 0.597, P less than 0.01; r = 0.503, P less than 0.05).

  13. The effect of age on systemic absorption and systemic disposition of bupivacaine after subarachnoid administration

    International Nuclear Information System (INIS)

    Veering, B.T.; Burm, A.G.; Vletter, A.A.; van den Hoeven, R.A.; Spierdijk, J.

    1991-01-01

    In order to evaluate the role of the pharmacokinetics of the age-related changes in the clinical profile of spinal anesthesia with bupivacaine, we studied the influence of age on the systemic absorption and systemic disposition of bupivacaine after subarachnoid administration in 20 male patients (22-81 yr), ASA Physical Status 1 or 2, by a stable isotope method. After subarachnoid administration of 3 ml 0.5% bupivacaine in 8% glucose, a deuterium-labeled analog (13.4 mg) was administered intravenously. Blood samples were collected for 24 h. Plasma concentrations of unlabeled and deuterium-labeled bupivacaine were determined with a combination of gas chromatography and mass fragmentography. Biexponential functions were fitted to the plasma concentration-time data of the deuterium-labeled bupivacaine. The systemic absorption was evaluated by means of deconvolution. Mono- and biexponential functions were fitted to the data of fraction absorbed versus time. The maximal height of analgesia and the duration of analgesia at T12 increased with age (r = 0.715, P less than 0.001; r = 0.640, P less than 0.01, respectively). In 18 patients the systemic absorption of bupivacaine was best described by a biexponential equation. The half-life of the slow systemic absorption process (r = -0.478; P less than 0.05) and the mean absorption time (r = -0.551; P less than 0.02) decreased with age. The total plasma clearance decreased with age (r = -0.650, P less than 0.002), whereas the mean residence time and terminal half-life increased with age (r = 0.597, P less than 0.01; r = 0.503, P less than 0.05)

  14. Thermionic detection of the ionic fragments of continiuum-state pair absorption systems

    International Nuclear Information System (INIS)

    Hotop, R.; Niemax, K.; Richter, J.; Weber, K.H.

    1981-01-01

    Using a thermionic diode we have detected the ionic fragments formed by associative ionization and dissociation after continuum-state pair absorption processes in Cs-Cs and Cs-K systems. Assuming an ionization probability of unity of the excited species and calibrating the pair absorption bands by taking into account the known photoionization cross section of the atoms we found excellent agreement with data from classical absorption measurements. (orig.)

  15. An Optical Biosensing Strategy Based on Selective Light Absorption and Wavelength Filtering from Chromogenic Reaction

    Directory of Open Access Journals (Sweden)

    Hyeong Jin Chun

    2018-03-01

    Full Text Available To overcome the time and space constraints in disease diagnosis via the biosensing approach, we developed a new signal-transducing strategy that can be applied to colorimetric optical biosensors. Our study is focused on implementation of a signal transduction technology that can directly translate the color intensity signals—that require complicated optical equipment for the analysis—into signals that can be easily counted with the naked eye. Based on the selective light absorption and wavelength-filtering principles, our new optical signaling transducer was built from a common computer monitor and a smartphone. In this signal transducer, the liquid crystal display (LCD panel of the computer monitor served as a light source and a signal guide generator. In addition, the smartphone was used as an optical receiver and signal display. As a biorecognition layer, a transparent and soft material-based biosensing channel was employed generating blue output via a target-specific bienzymatic chromogenic reaction. Using graphics editor software, we displayed the optical signal guide patterns containing multiple polygons (a triangle, circle, pentagon, heptagon, and 3/4 circle, each associated with a specified color ratio on the LCD monitor panel. During observation of signal guide patterns displayed on the LCD monitor panel using a smartphone camera via the target analyte-loaded biosensing channel as a color-filtering layer, the number of observed polygons changed according to the concentration of the target analyte via the spectral correlation between absorbance changes in a solution of the biosensing channel and color emission properties of each type of polygon. By simple counting of the changes in the number of polygons registered by the smartphone camera, we could efficiently measure the concentration of a target analyte in a sample without complicated and expensive optical instruments. In a demonstration test on glucose as a model analyte, we

  16. An Optical Biosensing Strategy Based on Selective Light Absorption and Wavelength Filtering from Chromogenic Reaction.

    Science.gov (United States)

    Chun, Hyeong Jin; Han, Yong Duk; Park, Yoo Min; Kim, Ka Ram; Lee, Seok Jae; Yoon, Hyun C

    2018-03-06

    To overcome the time and space constraints in disease diagnosis via the biosensing approach, we developed a new signal-transducing strategy that can be applied to colorimetric optical biosensors. Our study is focused on implementation of a signal transduction technology that can directly translate the color intensity signals-that require complicated optical equipment for the analysis-into signals that can be easily counted with the naked eye. Based on the selective light absorption and wavelength-filtering principles, our new optical signaling transducer was built from a common computer monitor and a smartphone. In this signal transducer, the liquid crystal display (LCD) panel of the computer monitor served as a light source and a signal guide generator. In addition, the smartphone was used as an optical receiver and signal display. As a biorecognition layer, a transparent and soft material-based biosensing channel was employed generating blue output via a target-specific bienzymatic chromogenic reaction. Using graphics editor software, we displayed the optical signal guide patterns containing multiple polygons (a triangle, circle, pentagon, heptagon, and 3/4 circle, each associated with a specified color ratio) on the LCD monitor panel. During observation of signal guide patterns displayed on the LCD monitor panel using a smartphone camera via the target analyte-loaded biosensing channel as a color-filtering layer, the number of observed polygons changed according to the concentration of the target analyte via the spectral correlation between absorbance changes in a solution of the biosensing channel and color emission properties of each type of polygon. By simple counting of the changes in the number of polygons registered by the smartphone camera, we could efficiently measure the concentration of a target analyte in a sample without complicated and expensive optical instruments. In a demonstration test on glucose as a model analyte, we could easily measure the

  17. Optoacoustic measurements of water vapor absorption at selected CO laser wavelengths in the 5-micron region

    Science.gov (United States)

    Menzies, R. T.; Shumate, M. S.

    1976-01-01

    Measurements of water vapor absorption were taken with a resonant optoacoustical detector (cylindrical pyrex detector, two BaF2 windows fitted into end plates at slight tilt to suppress Fabry-Perot resonances), for lack of confidence in existing spectral tabular data for the 5-7 micron region, as line shapes in the wing regions of water vapor lines are difficult to characterize. The measurements are required for air pollution studies using a CO laser, to find the differential absorption at the wavelengths in question due to atmospheric constituents other than water vapor. The design and performance of the optoacoustical detector are presented. Effects of absorption by ambient NO are considered, and the fixed-frequency discretely tunable CO laser is found suitable for monitoring urban NO concentrations in a fairly dry climate, using the water vapor absorption data obtained in the study.

  18. Tunable ultranarrow spectrum selective absorption in a graphene monolayer at terahertz frequency

    Science.gov (United States)

    Wu, Jun

    2016-06-01

    Complete absorption in a graphene monolayer at terahertz frequency through the critical coupling effect is investigated. It is achieved by sandwiching the graphene monolayer between a dielectric grating and a Bragg grating. The designed graphene absorber exhibits near-unity absorption at resonance but with an ultranarrow spectrum and antenna-like response, which is attributed to the combined effects of guided mode resonance with dielectric grating and the photonic band gap with Bragg grating. In addition to numerical simulation, the electric field distributions are also illustrated to provide a physical understanding of the perfect absorption effect. Furthermore, the absorption performance can be tuned by only changing the Fermi level of graphene, which is beneficial for real application. It is believed that this study may be useful for designing next-generation graphene-based optoelectronic devices.

  19. Thermodynamic performance analysis of a vapor compression–absorption cascaded refrigeration system

    International Nuclear Information System (INIS)

    Jain, Vaibhav; Kachhwaha, S.S.; Sachdeva, Gulshan

    2013-01-01

    Highlights: • Study includes first and second law analysis with alternatives refrigerants. • Power consumption in cascaded system is 61% less than vapor compression system. • COP of compression system is improved by 155% with cascaded absorption system. • Condenser is more sensitive to external fluid temperature as compare to evaporator. - Abstract: In the present study, a thermodynamic model for cascaded vapor compression–absorption system (CVCAS) has been developed which consists of a vapor compression refrigeration system (VCRS) coupled with single effect vapor absorption refrigeration system (VARS). Based on first and second laws, a comparative performance analysis of CVCAS and an independent VCRS has been carried out for a design capacity of 66.67 kW. The results show that the electric power consumption in CVCAS is reduced by 61% and COP of compression section is improved by 155% with respect to the corresponding values pertaining to a conventional VCRS. However there is a trade-off between these parameters and the rational efficiency which is found to decrease to half of that for a VCRS. The effect of various operating parameters, i.e., superheating, subcooling, cooling capacity, inlet temperature and the product of effectiveness and heat capacitance of external fluids are extensively studied on the COP, total irreversibility and rational efficiency of the CVCAS. Besides, the performance of environment friendly refrigerants such as R410A, R407C and R134A is found to be almost at par with that of R22. Hence, all the alternative refrigerants selected herein can serve as potential substitutes for R22. Furthermore, it has been found that reducing the irreversibility rate of the condenser by one unit due to decrease in condenser temperature depicted approximately 3.8 times greater reduction in the total irreversibility rate of the CVCAS, whereas unit reduction in the evaporator’s irreversibility rate due to increase in evaporator temperature reduced

  20. Resonance absorption spectroscopy for laser-ablated lanthanide atom. (1) Optimized experimental conditions for isotope-selective absorption of gadolinium (Contract research)

    International Nuclear Information System (INIS)

    Miyabe, Masabumi; Oba, Masaki; Iimura, Hideki; Akaoka, Katsuaki; Maruyama, Yoichiro; Wakaida, Ikuo; Watanabe, Kazuo

    2008-06-01

    For remote isotope analysis of low-decontaminated TRU fuel, we are developing an analytical technique on the basis of the resonance absorption spectroscopy for the laser-ablation plume. To improve isotopic selectivity and detection sensitivity of this technique, we measured absorption spectra of Gd atom with various plume production conditions (ablation laser intensity, ambient gas and its pressure) and observation conditions (transition, probe height from sample, observation timing). As a result, high resolution spectrum was obtained from the observation of slow component of the plume produced under low-pressure rare-gas ambient. The observed narrowest linewidth of about 0.85GHz was found to be close to the Doppler width estimated for Gd atom of room temperature. Furthermore, relaxation rate of higher meta-stable state was found to be higher than that of ground state, suggesting that use of the transition arising from ground state or lower meta-stable state is preferable for highly sensitive isotope analysis. (author)

  1. Studies of selected transuranium and lanthanide tri-iodides under pressure using absorption spectrophotometry

    International Nuclear Information System (INIS)

    Haire, R.G.; Young, J.P.; Peterson, J.R.; Tennessee Univ., Knoxville; Benedict, U.

    1987-01-01

    The anhydrous tri-iodides of plutonium, americium and curium under pressure have been investigated using absorption spectrophotometry. These initial studies on plutonium and curium tri-iodides together with the published data for americium tri-iodide show that the rhombohedral form of these compounds (BiI 3 -type structure) can be converted to the orthorhombic form (PuBr 3 -type structure) by applying pressure at room temperature. Absorption spectrophotometry can often differentiate between two crystallographic forms of a material and has been used in the present high-pressure studies to monitor the effects of pressure on the tri-iodides. A complication in these studies of the tri-iodides is a significant shift of their absorption edges with pressure from the near UV to the visible spectral region. With curium tri-iodide this shift causes interference with the major f-f absorption peaks and precludes identification by absorption spectrophotometry of the high pressure phase of CmI 3 . (orig.)

  2. Multispectral selective near-perfect light absorption by graphene monolayer using aperiodic multilayer microstructures

    Science.gov (United States)

    Zand, Iman; Dalir, Hamed; Chen, Ray T.; Dowling, Jonathan P.

    2018-03-01

    We investigate one-dimensional aperiodic multilayer microstructures in order to achieve near-total absorptions at preselected wavelengths in a graphene monolayer. The proposed structures are designed using a genetic optimization algorithm coupled to a transfer matrix code. Coupled-mode-theory analysis, consistent with transfer matrix method results, indicates the existence of a critical coupling in the graphene monolayer for perfect absorptions. Our findings show that the near-total-absorption peaks are highly tunable and can be controlled simultaneously or independently in a wide range of wavelengths in the near-infrared and visible ranges. The proposed approach is metal-free, does not require surface texturing or patterning, and can be also applied for other two-dimensional materials.

  3. Residential solar air conditioning: Energy and exergy analyses of an ammonia–water absorption cooling system

    International Nuclear Information System (INIS)

    Aman, J.; Ting, D.S.-K.; Henshaw, P.

    2014-01-01

    Large scale heat-driven absorption cooling systems are available in the marketplace for industrial applications but the concept of a solar driven absorption chiller for air-conditioning applications is relatively new. Absorption chillers have a lower efficiency than compression refrigeration systems, when used for small scale applications and this restrains the absorption cooling system from air conditioning applications in residential buildings. The potential of a solar driven ammonia–water absorption chiller for residential air conditioning application is discussed and analyzed in this paper. A thermodynamic model has been developed based on a 10 kW air cooled ammonia–water absorption chiller driven by solar thermal energy. Both energy and exergy analyses have been conducted to evaluate the performance of this residential scale cooling system. The analyses uncovered that the absorber is where the most exergy loss occurs (63%) followed by the generator (13%) and the condenser (11%). Furthermore, the exergy loss of the condenser and absorber greatly increase with temperature, the generator less so, and the exergy loss in the evaporator is the least sensitive to increasing temperature. -- Highlights: • 10 kW solar thermal driven ammonia–water air cooled absorption chiller is investigated. • Energy and exergy analyses have been done to enhance the thermal performance. • Low driving temperature heat sources have been optimized. • The efficiencies of the major components have been evaluated

  4. A experimental system for the checking of the absorption of E.C.A.G. graphite

    International Nuclear Information System (INIS)

    Raievski, V.; Vidal, R.

    1958-01-01

    A system is described for measuring the mean absorption cross section in thermal neutrons of graphite. This system consists of a graphite stack containing a Ra-Be source and a BF3 counter. A cavity in the stack receives the graphite to be studied or the graphite standard. By comparing the counting rates their absorption ratio can be deduced. The measurement is performed on graphite rods which have been machined before being placed in the pile. It provides the possibility of detecting over a batch of 1 ton of graphite, in a single measurement, a difference in absorption of 0.1 milli barn. (author) [fr

  5. Element selective detection of molecular species applying chromatographic techniques and diode laser atomic absorption spectrometry.

    Science.gov (United States)

    Kunze, K; Zybin, A; Koch, J; Franzke, J; Miclea, M; Niemax, K

    2004-12-01

    Tunable diode laser atomic absorption spectroscopy (DLAAS) combined with separation techniques and atomization in plasmas and flames is presented as a powerful method for analysis of molecular species. The analytical figures of merit of the technique are demonstrated by the measurement of Cr(VI) and Mn compounds, as well as molecular species including halogen atoms, hydrogen, carbon and sulfur.

  6. Intestinal alkaline phosphatase: selective endocytosis from the enterocyte brush border during fat absorption

    DEFF Research Database (Denmark)

    Hansen, Gert Helge; Niels-Christiansen, Lise-Lotte; Immerdal, Lissi

    2007-01-01

    explants. By immunofluorescence microscopy, fat absorption caused a translocation of IAP from the enterocyte brush border to the interior of the cell, whereas other brush-border enzymes were unaffected. By electron microscopy, the translocation occurred by a rapid (5 min) induction of endocytosis via...

  7. A Selection Method for COTS Systems

    DEFF Research Database (Denmark)

    Hedman, Jonas

    new skills and methods supporting the process of evaluating and selecting information systems. This paper presents a method for selecting COTS systems. The method includes the following phases: problem framing, requirements and appraisal, and selection of systems. The idea and distinguishing feature...... behind the method is that improved understanding of organizational' ends' or goals should govern the selection of a COTS system. This can also be expressed as a match or fit between ‘ends' (e.g. improved organizational effectiveness) and ‘means' (e.g. implementing COTS systems). This way of approaching...

  8. Materials Selection for Aerospace Systems

    Science.gov (United States)

    Arnold, Steven M.; Cebon, David; Ashby, Mike

    2012-01-01

    A systematic design-oriented, five-step approach to material selection is described: 1) establishing design requirements, 2) material screening, 3) ranking, 4) researching specific candidates and 5) applying specific cultural constraints to the selection process. At the core of this approach is the definition performance indices (i.e., particular combinations of material properties that embody the performance of a given component) in conjunction with material property charts. These material selection charts, which plot one property against another, are introduced and shown to provide a powerful graphical environment wherein one can apply and analyze quantitative selection criteria, such as those captured in performance indices, and make trade-offs between conflicting objectives. Finding a material with a high value of these indices maximizes the performance of the component. Two specific examples pertaining to aerospace (engine blades and pressure vessels) are examined, both at room temperature and elevated temperature (where time-dependent effects are important) to demonstrate the methodology. The discussion then turns to engineered/hybrid materials and how these can be effectively tailored to fill in holes in the material property space, so as to enable innovation and increases in performance as compared to monolithic materials. Finally, a brief discussion is presented on managing the data needed for materials selection, including collection, analysis, deployment, and maintenance issues.

  9. In vitro and in vivo percutaneous absorption of retinol from cosmetic formulations: Significance of the skin reservoir and prediction of systemic absorption

    International Nuclear Information System (INIS)

    Yourick, Jeffrey J.; Jung, Connie T.; Bronaugh, Robert L.

    2008-01-01

    The percutaneous absorption of retinol (Vitamin A) from cosmetic formulations was studied to predict systemic absorption and to understand the significance of the skin reservoir in in vitro absorption studies. Viable skin from fuzzy rat or human subjects was assembled in flow-through diffusion cells for in vitro absorption studies. In vivo absorption studies using fuzzy rats were performed in glass metabolism cages for collection of urine, feces, and body content. Retinol (0.3%) formulations (hydroalcoholic gel and oil-in-water emulsion) containing 3 H-retinol were applied and absorption was measured at 24 or 72 h. All percentages reported are % of applied dose. In vitro studies using human skin and the gel and emulsion vehicles found 0.3 and 1.3% retinol, respectively, in receptor fluid at 24 h. Levels of absorption in the receptor fluid increased over 72 h with the gel and emulsion vehicles. Using the gel vehicle, in vitro rat skin studies found 23% in skin and 6% in receptor fluid at 24 h, while 72-h studies found 18% in skin and 13% in receptor fluid. Thus, significant amounts of retinol remained in rat skin at 24 h and decreased over 72 h, with proportional increases in receptor fluid. In vivo rat studies with the gel found 4% systemic absorption of retinol after 24 h and systemic absorption did not increase at 72 h. Retinol remaining in rat skin after in vivo application was 18% and 13% of the applied dermal dose after 24 and 72 h, respectively. Similar observations were made with the oil-in water emulsion vehicle in the rat. Retinol formed a reservoir in rat skin both in vivo and in vitro. Little additional retinol was bioavailable after 24 h. Comparison of these in vitro and in vivo results for absorption through rat skin indicates that the 24-h in vitro receptor fluid value accurately estimated 24-h in vivo systemic absorption. Therefore, the best single estimate of retinol systemic absorption from in vitro human skin studies is the 24-h receptor fluid

  10. Automotive exhaust gas flow control for an ammonia–water absorption refrigeration system

    International Nuclear Information System (INIS)

    Rêgo, A.T.; Hanriot, S.M.; Oliveira, A.F.; Brito, P.; Rêgo, T.F.U.

    2014-01-01

    A considerable part of the energy generated by an automotive internal combustion engine is wasted as heat in the exhaust system. This wasted heat could be recovered and applied to power auxiliary systems in a vehicle, contributing to its overall energy efficiency. In the present work, the experimental analysis of an absorption refrigeration system was performed. The exhaust system of an automotive internal combustion engine was connected to the generator element of an absorption refrigeration system. The performance of the absorption refrigerator was evaluated as a function of the supplied heat. The use of a control strategy for the engine exhaust gas mass flow rate was implemented to optimize the system. Exhaust gas flow was controlled by step-motor actuated valves commanded by a microcontroller in which a proportional-integral control scheme was implemented. Information such as engine torque, speed, key temperatures in the absorption cycle, as well as internal temperatures of the refrigerator was measured in a transient regime. The results indicated that the refrigeration system exhibited better performance when the amount of input heat is controlled based on the temperature of the absorption cycle generator. It was possible to conclude that, by dynamically controlling the amount of input heat, the utilisation range of the absorption refrigeration system powered by exhaust gas heat could be expanded in order to incorporate high engine speed operating conditions. - Highlights: •An absorption refrigerator was driven by automotive exhaust gas heat. •A system for controlling the refrigeration system heat input was developed. •Excessive exhaust gas heat leads to ineffective operation of the refrigerator. •Control of refrigerator's generator temperature led to better performance. •The use of exhaust gas was possible for high engine speeds

  11. Absorption efficiency and heating kinetics of nanoparticles in the RF range for selective nanotherapy of cancer.

    Science.gov (United States)

    Letfullin, Renat R; Letfullin, Alla R; George, Thomas F

    2015-02-01

    Radio-frequency (RF) waves have an excellent ability to penetrate into the human body, giving a great opportunity to activate/heat nanoparticles delivered inside the body as a contrast agent for diagnosis and treatment purposes. However the heating of nanoparticles in the RF range of the spectrum is controversial in the research community because of the low power load of RF waves and low absorption of nanoparticles in the RF range. This study uses a phenomenological approach to estimate the absorption efficiency of metal and dielectric nanoparticles in the RF range through a study of heating kinetics of those particles in radio wave field. We also discuss the specific features of heating kinetics of nanoparticles, such as a short time scale for heating and cooling of nanoparticles in a liquid biological environment, and the effect of the radiation field structure on the heating kinetics by single-pulse and multipulse RF radiation. In this study a phenomenological approach was applied to estimate the absorption efficiency of radiofrequency radiation (RF) by metal and dielectric nanoparticles. Such nanoparticles can be designed and used for therapeutic purposes, like for localized heating and to activate nanoparticles by RF. The authors also discuss the differences in heating kinetics using single-pulse and multi-pulse RF radiation. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Optimization study of a single-effect water–lithium bromide absorption refrigeration system powered by flat-plate collector in hot regions

    International Nuclear Information System (INIS)

    Saleh, A.; Mosa, M.

    2014-01-01

    Highlights: • A comprehensive analysis for optimizing solar absorption system in hot region. • The most important parameter to be controlled is hot source temperature. • Ensuring appropriate choice of parameters, COP of absorption unit exceeds 0.8. • Results show that solar cooling systems are promising in hot regions. • The research aims to play a vital role to promote the use of renewable energy. - Abstract: This investigation has been carried out to present a comprehensive analysis for optimizing the operation of solar absorption system in hot regions. To optimize performance of the system, the hot source temperature should be controlled in function of incident solar radiation, chilled and cooling water temperatures. With an appropriate control, these external conditions can be monitored to detect and implement the actual optimization conditions. Adopting typical values encountered in hot regions, the overall system performance takes its optimal value at temperatures between 75 and 80 °C. It was found that in designing or selecting solar collector, selective coating type is necessary to produce hot water with potential around 80–90 °C needed to optimize operation of absorption unit. By ensuring an appropriate choice of components temperatures, COP of absorption unit can exceed the value 0.8. Cooling water temperature above 40 °C reduces significantly the performance of the unit which requires, under conditions of extremely high external temperatures, dimensioning and selection of condensers and absorbers that guarantee values less than this limit

  13. The selection of stopping power and mass energy absorption coefficient data for the HPA Code of Practice for dosimetry

    International Nuclear Information System (INIS)

    Williams, P.C.

    1985-01-01

    The author draws attention to a discussion by Cunningham and Schultz (1984) which states that, 'with the exception of the NACP and AAPM protocols, the selection of stopping power and energy absorption coefficient ratios has been based upon only the stated accelerating potential of the accelerator', and points out that the HPA Revised Code of Practice should be added to these exceptions. In calculating the HPA's new Csub(lambda) values, a similar, but not identical, approach was taken in order to determine the stopping power and absorption coefficient ratios at each radiation quality. It was recognised that the approximation of a spectrum to a monoenergetic spectrum of between 0.4 and 0.45 of the maximum energy, as had been done in calculating the values, given in ICRU Report 14, was incorrect. (U.K.)

  14. Quasar 2175 Å dust absorbers - II. Correlation analysis and relationship with other absorption line systems

    Science.gov (United States)

    Ma, Jingzhe; Ge, Jian; Prochaska, J. Xavier; Zhang, Shaohua; Ji, Tuo; Zhao, Yinan; Zhou, Hongyan; Lu, Honglin; Schneider, Donald P.

    2018-03-01

    We present the cold neutral content (H I and C I gas) of 13 quasar 2175 Å dust absorbers (2DAs) at z = 1.6-2.5 to investigate the correlation between the presence of the UV extinction bump with other physical characteristics. These 2DAs were initially selected from the Sloan Digital Sky Surveys I-III and followed up with the Keck-II telescope and the Multiple Mirror Telescope as detailed in our Paper I. We perform a correlation analysis between metallicity, redshift, depletion level, velocity width, and explore relationships between 2DAs and other absorption line systems. The 2DAs on average have higher metallicity, higher depletion levels, and larger velocity widths than Damped Lyman α absorbers (DLAs) or subDLAs. The correlation between [Zn/H] and [Fe/Zn] or [Zn/H] and logΔV90 can be used as alternative stellar mass estimators based on the well-established mass-metallicity relation. The estimated stellar masses of the 2DAs in this sample are in the range of ˜109 to ˜2 × 1011 M⊙ with a median value of ˜2 × 1010 M⊙. The relationship with other quasar absorption line systems can be described as (1) 2DAs are a subset of Mg II and Fe II absorbers, (2) 2DAs are preferentially metal-strong DLAs/subDLAs, (3) More importantly, all of the 2DAs show C I detections with logN(C I) > 14.0 cm-2, and (4) 2DAs can be used as molecular gas tracers. Their host galaxies are likely to be chemically enriched, evolved, massive (more massive than typical DLA/subDLA galaxies), and presumably star-forming galaxies.

  15. Emergency membrane contactor based absorption system for ammonia leaks in water treatment plants.

    Science.gov (United States)

    Shao, Jiahui; Fang, Xuliang; He, Yiliang; Jin, Qiang

    2008-01-01

    Abstract Because of the suspected health risks of trihalomethanes (THMs), more and more water treatment plants have replaced traditional chlorine disinfection process with chloramines but often without the proper absorption system installed in the case of ammonia leaks in the storage room. A pilot plant membrane absorption system was developed and installed in a water treatment plant for this purpose. Experimentally determined contact angle, surface tension, and corrosion tests indicated that the sulfuric acid was the proper choice as the absorbent for leaking ammonia using polypropylene hollow fiber membrane contactor. Effects of several operating conditions on the mass transfer coefficient, ammonia absorption, and removal efficiency were examined, including the liquid concentration, liquid velocity, and feed gas concentration. Under the operation conditions investigated, the gas absorption efficiency over 99.9% was achieved. This indicated that the designed pilot plant membrane absorption system was effective to absorb the leaking ammonia in the model storage room. The removal rate of the ammonia in the model storage room was also experimentally and theoretically found to be primarily determined by the ammonia suction flow rate from the ammonia storage room to the membrane contactor. The ammonia removal rate of 99.9% was expected to be achieved within 1.3 h at the ammonia gas flow rate of 500 m3/h. The success of the pilot plant membrane absorption system developed in this study illustrated the potential of this technology for ammonia leaks in water treatment plant, also paved the way towards a larger scale application.

  16. Remote Laser Evaporative Molecular Absorption Spectroscopy Sensor System

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a sensor system capable of remotely probing the molecular composition of cold solar system targets (asteroids, comets, planets, moons), such as from a...

  17. LiBr absorption systems integrated with high–efficiency IGSG plant

    DEFF Research Database (Denmark)

    Rokni, Masoud; Bellomare, Filippo

    2015-01-01

    vapor compression inverse cycles; waste heat from other systems can in fact be used as an efficient input instead of electrical energy. The opportunity to integrate Li-Br absorption systems with a high-efficiency energy plant was studied; rejected heat from a Municipal Solid Waste Gasification Plant......Over the last few years, the energy demand for cooling systems is increasing; different solutions in fact have been proposed in order to minimize the energetic and environmental impact of this trend. In this direction, absorption cooling systems are recognized as a valid alternative to traditional...

  18. Increasing efficacy and reducing systemic absorption of brimonidine tartrate ophthalmic gels in rabbits.

    Science.gov (United States)

    Pang, Xiaochen; Li, Jiawei; Pi, Jiaxin; Qi, Dongli; Guo, Pan; Li, Nan; Wu, Yumei; Liu, Zhidong

    2018-03-01

    Systemic absorption of ocularly administered Brimonidine Tartrate has been reported to give rise to several side-effects. Hence, it has become crucial to develop a delivery system that could increase efficacy and reduce systemic absorption. Therefore, the present work aims to develop Brimonidine Tartrate gels with different concentrations (0.05%, 0.1%, and 0.2% w/v, respectively) using Carbopol 974 P and HPMC E4M, and compare the therapeutic efficacy and systemic absorption with that of eye drop (0.2%, w/v) by UPLC-MS/MS. The result of histological analysis did not show any morphological or structural changes after the administration of formulations. In vitro residence time studies demonstrated that the gels exhibited a better precorneal residence time as compared with the eye drop. The gels with lower concentrations of the drug (0.05% and 0.1%, w/v) could significantly decrease intraocular pressure (IOP) in both normal and water-loaded rabbits as compared to the eye drop. Finally, the values of the ratio of AUC (0→∞) in comparison to eye drop showed the gels with lower concentrations of Brimonidine Tartrate could decrease the systemic absorption. From the result, it can be concluded the 0.1% ophthalmic gel has a potential to improve therapeutic efficacy and reduce the potential toxicity caused by systemic absorption.

  19. Process and device for the excitation and selective dissociation by absorption of a laser light and application to isotopic enrichment

    International Nuclear Information System (INIS)

    Rigny, Paul.

    1975-01-01

    The description is given of a process for the excitation and selective dissociation by absorption of the monochromatic light emitted by a high power laser. The laser light at frequency ν 1 is beamed on to an isotopic mixture of gaseous molecules, some of these molecules presenting transitions, between two vibration levels corresponding to a given isotope, separated by an energy interval ΔE 1 =2h ν 1 , and the molecules of a given isotopic species are thus preferentially dissociated into several component parts [fr

  20. Highly doped semiconductor plasmonic nanoantenna arrays for polarization selective broadband surface-enhanced infrared absorption spectroscopy of vanillin

    Science.gov (United States)

    Barho, Franziska B.; Gonzalez-Posada, Fernando; Milla, Maria-Jose; Bomers, Mario; Cerutti, Laurent; Tournié, Eric; Taliercio, Thierry

    2017-11-01

    Tailored plasmonic nanoantennas are needed for diverse applications, among those sensing. Surface-enhanced infrared absorption (SEIRA) spectroscopy using adapted nanoantenna substrates is an efficient technique for the selective detection of molecules by their vibrational spectra, even in small quantity. Highly doped semiconductors have been proposed as innovative materials for plasmonics, especially for more flexibility concerning the targeted spectral range. Here, we report on rectangular-shaped, highly Si-doped InAsSb nanoantennas sustaining polarization switchable longitudinal and transverse plasmonic resonances in the mid-infrared. For small array periodicities, the highest reflectance intensity is obtained. Large periodicities can be used to combine localized surface plasmon resonances (SPR) with array resonances, as shown in electromagnetic calculations. The nanoantenna arrays can be efficiently used for broadband SEIRA spectroscopy, exploiting the spectral overlap between the large longitudinal or transverse plasmonic resonances and narrow infrared active absorption features of an analyte molecule. We demonstrate an increase of the vibrational line intensity up to a factor of 5.7 of infrared-active absorption features of vanillin in the fingerprint spectral region, yielding enhancement factors of three to four orders of magnitude. Moreover, an optimized readout for SPR sensing is proposed based on slightly overlapping longitudinal and transverse localized SPR.

  1. Highly doped semiconductor plasmonic nanoantenna arrays for polarization selective broadband surface-enhanced infrared absorption spectroscopy of vanillin

    Directory of Open Access Journals (Sweden)

    Barho Franziska B.

    2017-11-01

    Full Text Available Tailored plasmonic nanoantennas are needed for diverse applications, among those sensing. Surface-enhanced infrared absorption (SEIRA spectroscopy using adapted nanoantenna substrates is an efficient technique for the selective detection of molecules by their vibrational spectra, even in small quantity. Highly doped semiconductors have been proposed as innovative materials for plasmonics, especially for more flexibility concerning the targeted spectral range. Here, we report on rectangular-shaped, highly Si-doped InAsSb nanoantennas sustaining polarization switchable longitudinal and transverse plasmonic resonances in the mid-infrared. For small array periodicities, the highest reflectance intensity is obtained. Large periodicities can be used to combine localized surface plasmon resonances (SPR with array resonances, as shown in electromagnetic calculations. The nanoantenna arrays can be efficiently used for broadband SEIRA spectroscopy, exploiting the spectral overlap between the large longitudinal or transverse plasmonic resonances and narrow infrared active absorption features of an analyte molecule. We demonstrate an increase of the vibrational line intensity up to a factor of 5.7 of infrared-active absorption features of vanillin in the fingerprint spectral region, yielding enhancement factors of three to four orders of magnitude. Moreover, an optimized readout for SPR sensing is proposed based on slightly overlapping longitudinal and transverse localized SPR.

  2. X-ray absorption spectroscopy in biological systems. Opportunities and limitations

    Energy Technology Data Exchange (ETDEWEB)

    Bovenkamp, Gudrun Lisa

    2013-05-15

    X-ray absorption spectroscopy has become more important for applications in the material sciences, geology, environmental science and biology, specifically in the field of molecular biology. The scope of this thesis is to add more experimental evidence in order to show how applicable X-ray absorption near edge structure (XANES) is to biology. Two biological systems were investigated, at the molecular level, lead uptake in plants and the effect of silver on bacteria. This investigation also included an analysis of the sensitivity of Pb L{sub 3}- and Ag L{sub 3}-XANES spectra with regard to their chemical environment. It was shown that Pb L{sub 3}- and Ag L{sub 3}-XANES spectra are sensitive to an environment with at least differences in the second coordination shell. The non-destructive and element specific properties of XANES are the key advantages that were very important for this investigation. However, in both projects the adequate selection of reference compounds, which required in some cases a chemical synthesis, was the critical factor to determine the chemical speciation and, finally, possible uptake and storage mechanisms for plants and antibacterial mechanisms of silver. The chemical environment of Pb in roots and leaves of plants from four different plant families and a lichen from a former lead mining site in the Eifel mountains in Germany was determined using both solid compounds and aqueous solutions of different ionic strength, which simulate the plant environment. The results can be interpreted in such a way that lead is sorbed on the surface of cell walls. Silver bonding as reaction with Staphylococcus aureus, Listeria monocytogenes, and Escherichia coli bacteria was determined using inorganic silver compounds and synthesized silver amino acids. Silver binds to sulfur, amine and carboxyl groups in amino acids.

  3. X-ray absorption spectroscopy in biological systems. Opportunities and limitations

    International Nuclear Information System (INIS)

    Bovenkamp, Gudrun Lisa

    2013-05-01

    X-ray absorption spectroscopy has become more important for applications in the material sciences, geology, environmental science and biology, specifically in the field of molecular biology. The scope of this thesis is to add more experimental evidence in order to show how applicable X-ray absorption near edge structure (XANES) is to biology. Two biological systems were investigated, at the molecular level, lead uptake in plants and the effect of silver on bacteria. This investigation also included an analysis of the sensitivity of Pb L 3 - and Ag L 3 -XANES spectra with regard to their chemical environment. It was shown that Pb L 3 - and Ag L 3 -XANES spectra are sensitive to an environment with at least differences in the second coordination shell. The non-destructive and element specific properties of XANES are the key advantages that were very important for this investigation. However, in both projects the adequate selection of reference compounds, which required in some cases a chemical synthesis, was the critical factor to determine the chemical speciation and, finally, possible uptake and storage mechanisms for plants and antibacterial mechanisms of silver. The chemical environment of Pb in roots and leaves of plants from four different plant families and a lichen from a former lead mining site in the Eifel mountains in Germany was determined using both solid compounds and aqueous solutions of different ionic strength, which simulate the plant environment. The results can be interpreted in such a way that lead is sorbed on the surface of cell walls. Silver bonding as reaction with Staphylococcus aureus, Listeria monocytogenes, and Escherichia coli bacteria was determined using inorganic silver compounds and synthesized silver amino acids. Silver binds to sulfur, amine and carboxyl groups in amino acids.

  4. Expert System Model for Educational Personnel Selection

    Directory of Open Access Journals (Sweden)

    Héctor A. Tabares-Ospina

    2013-06-01

    Full Text Available The staff selection is a difficult task due to the subjectivity that the evaluation means. This process can be complemented using a system to support decision. This paper presents the implementation of an expert system to systematize the selection process of professors. The management of software development is divided into 4 parts: requirements, design, implementation and commissioning. The proposed system models a specific knowledge through relationships between variables evidence and objective.

  5. Site- and phase-selective x-ray absorption spectroscopy based on phase-retrieval calculation

    International Nuclear Information System (INIS)

    Kawaguchi, Tomoya; Fukuda, Katsutoshi; Matsubara, Eiichiro

    2017-01-01

    Understanding the chemical state of a particular element with multiple crystallographic sites and/or phases is essential to unlocking the origin of material properties. To this end, resonant x-ray diffraction spectroscopy (RXDS) achieved through a combination of x-ray diffraction (XRD) and x-ray absorption spectroscopy (XAS) techniques can allow for the measurement of diffraction anomalous fine structure (DAFS). This is expected to provide a peerless tool for electronic/local structural analyses of materials with complicated structures thanks to its capability to extract spectroscopic information about a given element at each crystallographic site and/or phase. At present, one of the major challenges for the practical application of RXDS is the rigorous determination of resonant terms from observed DAFS, as this requires somehow determining the phase change in the elastic scattering around the absorption edge from the scattering intensity. This is widely known in the field of XRD as the phase problem. The present review describes the basics of this problem, including the relevant background and theory for DAFS and a guide to a newly-developed phase-retrieval method based on the logarithmic dispersion relation that makes it possible to analyze DAFS without suffering from the intrinsic ambiguities of conventional iterative-fitting. Several matters relating to data collection and correction of RXDS are also covered, with a final emphasis on the great potential of powder-sample-based RXDS (P-RXDS) to be used in various applications relevant to practical materials, including antisite-defect-type electrode materials for lithium-ion batteries. (topical review)

  6. Parametric analysis of an irreversible proton exchange membrane fuel cell/absorption refrigerator hybrid system

    International Nuclear Information System (INIS)

    Yang, Puqing; Zhang, Houcheng

    2015-01-01

    A hybrid system mainly consisting of a PEMFC (proton exchange membrane fuel cell) and an absorption refrigerator is proposed, where the PEMFC directly converts the chemical energy contained in the hydrogen into electrical and thermal energies, and the thermal energy is transferred to drive the bottoming absorption refrigerator for cooling purpose. By considering the existing irreversible losses in the hybrid system, the operating current density region of the PEMFC permits the absorption refrigerator to exert its function is determined and the analytical expressions for the equivalent power output and efficiency of the hybrid system under different operating conditions are specified. Numerical calculations show that the equivalent maximum power density and the corresponding efficiency of the hybrid system can be respectively increased by 5.3% and 6.8% compared to that of the stand-alone PEMFC. Comprehensive parametric analyses are conducted to reveal the effects of the internal irreversibility of the absorption refrigerator, operating current density, operating temperature and operating pressure of the PEMFC, and some integrated parameters related to the thermodynamic losses on the performance of the hybrid system. The model presented in the paper is more general than previous study, and the results for some special cases can be directly derived from this paper. - Highlights: • A CHP system composed of a PEMFC and an absorption refrigerator is proposed. • Current density region enables the absorption refrigerator to work is determined. • Multiple irreversible losses in the system are analytically characterized. • Maximum power density and corresponding efficiency can be increased by 5.3% and 6.8%. • Effects of some designing and operating parameters on the performance are discussed

  7. Moisture movement in cement-based repair systems monitored by X-ray absorption

    NARCIS (Netherlands)

    Lukovic, M.; Ye, G.; Schlangen, H.E.J.G.; van Breugel, K.

    2017-01-01

    In concrete repair systems, material properties in the repair material and interface are greatly influenced by the initial moisture content of the concrete (or mortar) substrate. In order to quantify moisture profiles inside the repair system, X-ray absorption was used. Preliminary studies are

  8. Safety, tolerability, and systemic absorption of dapivirine vaginal microbicide gel in healthy, HIV-negative women

    NARCIS (Netherlands)

    Nel, Annalene M.; Coplan, Paul; van de Wijgert, Janneke H.; Kapiga, Saidi H.; von Mollendorf, Claire; Geubbels, Eveline; Vyankandondera, Joseph; Rees, Helen V.; Masenga, Gileard; Kiwelu, Ireen; Moyes, Jocelyn; Smythe, Shanique C.

    2009-01-01

    To assess the local and systemic safety of dapivirine vaginal gel vs. placebo gel as well as the systemic absorption of dapivirine in healthy, HIV-negative women. Two prospective, randomized, double-blind, placebo-controlled phase I/II studies were conducted at five research centers, four in Africa

  9. Absorption of electromagnetic field energy by superfluid system of atoms with electric dipole moment

    International Nuclear Information System (INIS)

    Poluektov, Yu.M.

    2014-01-01

    The modified Gross-Pitaevskii equation which takes into account relaxation and interaction with alternating electromagnetic field is used to consider the absorption of electromagnetic field energy by a superfluid system on the assumption that the atoms has intrinsic dipole moment. It is shown that the absorption may be of a resonant behavior only if the dispersion curves of the electromagnetic wave and the excitations of the superfluid system intersect. It is remarkable that such a situation is possible if the superfluid system has a branch of excitations with the energy gap at low momenta. The experiments on absorption of microwaves in superfluid helium are interpreted as evidence of existence of such gap excitations. A possible modification of the excitation spectrum of superfluid helium in the presence of excitation branch with energy gap is dis-cussed qualitatively

  10. Photosynthetic antennae systems: energy transport and optical absorption

    International Nuclear Information System (INIS)

    Reineker, P.; Supritz, Ch.; Warns, Ch.; Barvik, I.

    2004-01-01

    The energy transport and the optical line shape of molecular aggregates, modeling bacteria photosynthetic light-harvesting systems (chlorosomes in the case of Chlorobium tepidum or Chloroflexus aurantiacus and LH2 in the case of Rhodopseudomonas acidophila) is investigated theoretically. The molecular units are described by two-level systems with an average excitation energy ε and interacting with each other through nearest-neighbor interactions. For LH2 an elliptical deformation of the ring is also allowed. Furthermore, dynamic and in the case of LH2 also quasi-static fluctuations of the local excitation energies are taken into account, simulating fast molecular vibrations and slow motions of the protein backbone, respectively. The fluctuations are described by Gaussian Markov processes in the case of the chlorosomes and by colored dichotomic Markov processes, with exponentially decaying correlation functions, with small (λ s ) and large (λ) decay constants, in the case of LH2

  11. Absorptive capacity, technological innovation, and product life cycle: a system dynamics model.

    Science.gov (United States)

    Zou, Bo; Guo, Feng; Guo, Jinyu

    2016-01-01

    While past research has recognized the importance of the dynamic nature of absorptive capacity, there is limited knowledge on how to generate a fair and comprehensive analytical framework. Based on interviews with 24 Chinese firms, this study develops a system-dynamics model that incorporates an important feedback loop among absorptive capacity, technological innovation, and product life cycle (PLC). The simulation results reveal that (1) PLC affects the dynamic process of absorptive capacity; (2) the absorptive capacity of a firm peaks in the growth stage of PLC, and (3) the market demand at different PLC stages is the main driving force in firms' technological innovations. This study also explores a sensitivity simulation using the variables of (1) time spent in founding an external knowledge network, (2) research and development period, and (3) knowledge diversity. The sensitivity simulation results show that the changes of these three variables have a greater impact on absorptive capacity and technological innovation during growth and maturity stages than in the introduction and declining stages of PLC. We provide suggestions on how firms can adjust management policies to improve their absorptive capacity and technological innovation performance during different PLC stages.

  12. Experimental results of a direct air-cooled ammonia–lithium nitrate absorption refrigeration system

    International Nuclear Information System (INIS)

    Llamas-Guillén, S.U.; Cuevas, R.; Best, R.; Gómez, V.H.

    2014-01-01

    Absorption thermal cooling systems driven by renewable energy are a viable option in order to reduce fossil fuel consumption and the associated emissions. This work shows the results of an air cooled absorption cooling prototype working with an ammonia–lithium nitrate mixture at high ambient temperatures. An absorption refrigeration system was designed and built. The prototype is a one stage ammonia–lithium nitrate air cooled chiller. The experimental system was instrumented to evaluate each component. This paper shows the operation conditions in the experimental unit as well as some of the heat loads encountered at different operating conditions. The system was operated successfully at ambient temperatures in the range of 25–35 °C. A series of test showed that even at ambient temperatures it can be operated at evaporator temperatures below 10 °C producing chilled water for air conditioning applications such as radiative cooling panels. The system proved to stabilize very quickly and no risk of crystallization was encountered so the first results are promising in order to continue with the development of a more advanced prototype. - Highlights: •Experimental results of a direct air-cooled ammonia–lithium nitrate system. •The prototype is a one stage ammonia–lithium nitrate air cooled chiller. •The absorption system was operated successfully at ambient temperatures. •Cooling loads of 4.5 kW were reached in the chilled water side

  13. Method for Business Process Management System Selection

    OpenAIRE

    Westelaken, van de, Thijs; Terwee, Bas; Ravesteijn, Pascal

    2013-01-01

    In recent years business process management (BPM) and specifically information systems that support the analysis, design and execution of processes (also called business process management systems (BPMS)) are getting more attention. This has lead to an increase in research on BPM and BPMS. However the research on BPMS is mostly focused on the architecture of the system and how to implement such systems. How to select a BPM system that fits the strategy and goals of a specific organization is ...

  14. Prototype explosives detection system based on nuclear resonance absorption in nitrogen

    International Nuclear Information System (INIS)

    Morgado, R.E.; Arnone, G.J.; Cappiello, C.C.

    1996-01-01

    A laboratory prototype system has been developed for the experimental evaluation of an explosives detection technique based on nuclear resonance absorption of gamma rays in nitrogen. Major subsystems include a radiofrequency quadrupole proton accelerator and associated beam transport system, a high-power gamma-ray production target, an airline-luggage tomographic inspection system, and an image- processing/detection-alarm subsystem. The detection system performance, based on a limited experimental test, is reported

  15. Folate absorption

    International Nuclear Information System (INIS)

    Baker, S.J.

    1976-01-01

    Folate is the generic term given to numerous compounds of pteroic acid with glutamic acid. Knowledge of absorption is limited because of the complexities introduced by the variety of compounds and because of the inadequacy of investigational methods. Two assay methods are in use, namely microbiological and radioactive. Techniques used to study absorption include measurement of urinary excretion, serum concentration, faecal excretion, intestinal perfusion, and haematological response. It is probably necessary to test absorption of both pteroylmonoglutamic acid and one or more polyglutamates, and such tests would be facilitated by availability of synthesized compounds labelled with radioactive tracers at specifically selected sites. (author)

  16. Thermodynamic analysis of an absorption refrigeration system used to cool down the intake air in an Internal Combustion Engine

    International Nuclear Information System (INIS)

    Novella, R.; Dolz, V.; Martín, J.; Royo-Pascual, L.

    2017-01-01

    Highlights: • Enough power in the exhaust gases is available to operate the absorption cycle. • Three engine operating points are presented in the article. • Improvement potential up to 4% is possible in the engine indicated efficiency. • Engine indicated efficiency benefit was experimentally confirmed by direct testing. - Abstract: This paper deals with the thermodynamic analysis of an absorption refrigeration cycle used to cool down the temperature of the intake air in an Internal Combustion Engine using as a heat source the exhaust gas of the engine. The solution of ammonia-water has been selected due to the stability for a wide range of operating temperatures and pressures and the low freezing point. The effects of operating temperatures, pressures, concentrations of strong and weak solutions in the absorption refrigeration cycle were examined to achieve proper heat rejection to the ambient. Potential of increasing Internal Combustion Engine efficiency and reduce pollutant emissions was estimated by means of theoretical models and experimental tests. In order to provide boundary conditions for the absorption refrigeration cycle and to simulate its effect on engine performance, a 0D thermodynamic model was used to reproduce the engine performance when the intake air is cooled. Furthermore, a detailed experimental work was carried out to validate the results in real engine operation. Theoretical results show how the absorption refrigeration system decreases the intake air flow temperature down to a temperature around 5 °C and even lower by using the bottoming waste heat energy available in the exhaust gases in a wide range of engine operating conditions. In addition, the theoretical analysis estimates the potential of the strategy for increasing the engine indicated efficiency in levels up to 4% also at the operating conditions under evaluation. Finally, this predicted benefit in engine indicated efficiency has been experimentally confirmed by direct

  17. Optimisation of optical absorption properties of spectrally selective C-NiO composite coatings

    CSIR Research Space (South Africa)

    Tile, N

    2011-05-01

    Full Text Available and expensive. Carbon in Nickel Oxide (C-NiO) composite material has been found to have a very good spectral selectivity1,2. Moreover this material has a potential of low cost large scale fabrication since it can be fabricated by a simple sol-gel technique...

  18. Threshold fluence measurement for laser liftoff of InP thin films by selective absorption

    NARCIS (Netherlands)

    Jan, A.; Reeves, B.A.; Van De Burgt, Y.B.; Hayes, G.J.; Clemens, B.M.

    2018-01-01

    e explore conditions for achieving laser liftoff in epitaxially grown heterojunctions, in which single crystal thin films can be separated from their growth substrates using a selectively absorbing buried intermediate layer. Because this highly non-linear process is subject to a variety of process

  19. Preliminary aseismic analysis on bolts of driving mechanism in absorption sphere shutdown system

    International Nuclear Information System (INIS)

    Chen Feng; Li Tianjin; Zhang Zhengming; Huang Zhiyong; Bo Hanliang

    2012-01-01

    The absorption sphere shutdown system performs an important role in reactivity regulating and control. Driving mechanism is a set of key mechanical moving parts which is used to control falling of absorption spheres in absorption sphere shutdown system. It is about 5 m for driving mechanism with the slim structure, which is connected with the upper supported plate of metal reactor internals through storage vessel with bolts. Both the storage vessel and driving mechanism are equipment of seismic classification I. It is significant to calculate and check the bolts strength of driving mechanism. In this paper, complicate structure of driving mechanism was simplified to three variable cross sections and statically indeterminate problem was solved. The bolts at the bottom and on the top of the storage vessel were calculated and checked. The preliminary results indicate that the bolts strength is reliable and safe, and the supporting force at the most weak point of driving mechanism is as well obtained. (authors)

  20. LiCl Dehumidifier LiBr absorption chiller hybrid air conditioning system with energy recovery

    Science.gov (United States)

    Ko, Suk M.

    1980-01-01

    This invention relates to a hybrid air conditioning system that combines a solar powered LiCl dehumidifier with a LiBr absorption chiller. The desiccant dehumidifier removes the latent load by absorbing moisture from the air, and the sensible load is removed by the absorption chiller. The desiccant dehumidifier is coupled to a regenerator and the desiccant in the regenerator is heated by solar heated hot water to drive the moisture therefrom before being fed back to the dehumidifier. The heat of vaporization expended in the desiccant regenerator is recovered and used to partially preheat the driving fluid of the absorption chiller, thus substantially improving the overall COP of the hybrid system.

  1. Synthesis of integrated absorption refrigeration systems involving economic and environmental objectives and quantifying social benefits

    International Nuclear Information System (INIS)

    Lira-Barragán, Luis Fernando; Ponce-Ortega, José María; Serna-González, Medardo; El-Halwagi, Mahmoud M.

    2013-01-01

    This paper presents a new methodology for energy integration of systems that require absorption refrigeration. It allows heat exchange among process hot and cold streams and the integration of excess process heat as well as external utilities provided by solar energy, fossil fuels and biofuels. An optimization formulation is developed to address the multiple objectives of simultaneously minimizing the total annualized cost and the greenhouse gas emissions while the social impact is measured by the number of jobs generated by the project in the entire life cycle. The economic function accounts for the tax credit obtained by the reduction of greenhouse gas emissions when cleaner technologies are used. The proposed model also considers the optimal selection of different types of solar collectors and the optimal time-based usage of solar energy, fossil fuel, and biofuel. Two example problems are presented to show the applicability of the proposed methodology. -- Highlights: ► An approach for the thermal integration of refrigeration processes is proposed. ► Different forms of sustainable energies are considered in the optimization process. ► Economic and environmental objectives are considered quantifying the number of jobs. ► The availability for the different forms of energy is taken into account. ► Results show significant advantages obtained with the proposed approach

  2. Airborne differential absorption lidar system for measurements of atmospheric water vapor and aerosols

    Science.gov (United States)

    Carter, Arlen F.; Allen, Robert J.; Mayo, M. Neale; Butler, Carolyn F.; Grossman, Benoist E.; Ismail, Syed; Grant, William B.; Browell, Edward V.; Higdon, Noah S.; Mayor, Shane D.; hide

    1994-01-01

    An airborne differential absorption lidar (DIAL) system has been developed at the NASA Langley Research Center for remote measurements of atmospheric water vapor (H2O) and aerosols. A solid-state alexandrite laser with a 1-pm linewidth and greater than 99.85% spectral purity was used as the on-line transmitter. Solid-state avalanche photodiode detector technology has replaced photomultiplier tubes in the receiver system, providing an average increase by a factor of 1.5-2.5 in the signal-to-noise ratio of the H2O measurement. By incorporating advanced diagnostic and data-acquisition instrumentation into other subsystems, we achieved additional improvements in system operational reliability and measurement accuracy. Laboratory spectroscopic measurements of H2O absorption-line parameters were performed to reduce the uncertainties in our knowledge of the absorption cross sections. Line-center H2O absorption cross sections were determined, with errors of 3-6%, for more than 120 lines in the 720-nm region. Flight tests of the system were conducted during 1989-1991 on the NASA Wallops Flight Facility Electra aircraft, and extensive intercomparison measurements were performed with dew-point hygrometers and H2O radiosondes. The H2O distributions measured with the DIAL system differed by less than 10% from the profiles determined with the in situ probes in a variety of atmospheric conditions.

  3. Reversible Assembly of Graphitic Carbon Nitride 3D Network for Highly Selective Dyes Absorption and Regeneration.

    Science.gov (United States)

    Zhang, Yuye; Zhou, Zhixin; Shen, Yanfei; Zhou, Qing; Wang, Jianhai; Liu, Anran; Liu, Songqin; Zhang, Yuanjian

    2016-09-27

    Responsive assembly of 2D materials is of great interest for a range of applications. In this work, interfacial functionalized carbon nitride (CN) nanofibers were synthesized by hydrolyzing bulk CN in sodium hydroxide solution. The reversible assemble and disassemble behavior of the as-prepared CN nanofibers was investigated by using CO2 as a trigger to form a hydrogel network at first. Compared to the most widespread absorbent materials such as active carbon, graphene and previously reported supramolecular gel, the proposed CN hydrogel not only exhibited a competitive absorbing capacity (maximum absorbing capacity of methylene blue up to 402 mg/g) but also overcame the typical deficiencies such as poor selectivity and high energy-consuming regeneration. This work would provide a strategy to construct a 3D CN network and open an avenue for developing smart assembly for potential applications ranging from environment to selective extraction.

  4. Aluminium or copper substrate panel for selective absorption of solar energy

    Science.gov (United States)

    Roberts, M. L.; Sharpe, M. H.; Krupnick, A. C. (Inventor)

    1979-01-01

    A method for making panels which selectively absorb solar energy is disclosed. The panels are comprised of an aluminum substrate, a layer of zinc thereon, a layer of nickel over the zinc layer and an outer layer of solar energy absorbing nickel oxide or a copper substrate with a layer of nickel thereon and a layer of solar energy absorbing nickel oxide distal from the copper substrate.

  5. The influence of coordination geometry and valency on the K-edge absorption near edge spectra of selected chromium compounds

    International Nuclear Information System (INIS)

    Pantelouris, A.; Modrow, H.; Pantelouris, M.; Hormes, J.; Reinen, D.

    2004-01-01

    X-ray absorption spectra at the chromium K-edge are reported for a number of selected chromium compounds of known chemical structure. The spectra were obtained with use of synchrotron radiation available at the ELectron Stretcher Accelerator ELSA in Bonn. The compounds studied include the tetrahedrally coordinated compounds Ca 2 Ge 0.8 Cr 0.2 O 4 , Ba 2 Ge 0.1 Cr 0.9 O 4 , Sr 2 CrO 4 , Ca 2 (PO 4 ) x (CrO 4 ) 1-x Cl (x=0.25,0.5), Ca 5 (CrO 4 ) 3 Cl, CrO 3 , the octahedrally coordinated compounds Cr(II)-acetate, CrCl 3 , CrF 3 , Cr 2 O 3 , KCr(SO 4 ) 2 · 12H 2 O, CrO 2 and cubic coordinated metallic chromium. In these compounds chromium exhibits a wide range of formal oxidation states (0 to VI). The absorption features in the near edge region are shown to be characteristic of the spatial environment of the absorbing atom. The occurrence of a single pre-edge line easily allows one to distinguish between tetrahedral and octahedral coordination geometry, whereas the energy position of the absorption edge is found to be very sensitive to the valency of the excited chromium atom. Calculations of the ionisation potential of Cr in different oxidation states using the non-relativistic Hartree-Fock method (Froese-Fischer) confirm that the ionisation limit shifts to higher energy with increasing Cr valency. More detailed information on the electronic structure of the different compounds is gained by real-space full multiple scattering calculations using the FEFF8 code

  6. The influence of coordination geometry and valency on the K-edge absorption near edge spectra of selected chromium compounds

    Energy Technology Data Exchange (ETDEWEB)

    Pantelouris, A.; Modrow, H.; Pantelouris, M.; Hormes, J.; Reinen, D

    2004-05-10

    X-ray absorption spectra at the chromium K-edge are reported for a number of selected chromium compounds of known chemical structure. The spectra were obtained with use of synchrotron radiation available at the ELectron Stretcher Accelerator ELSA in Bonn. The compounds studied include the tetrahedrally coordinated compounds Ca{sub 2}Ge{sub 0.8}Cr{sub 0.2}O{sub 4}, Ba{sub 2}Ge{sub 0.1}Cr{sub 0.9}O{sub 4}, Sr{sub 2}CrO{sub 4}, Ca{sub 2}(PO{sub 4}){sub x}(CrO{sub 4}){sub 1-x}Cl (x=0.25,0.5), Ca{sub 5}(CrO{sub 4}){sub 3}Cl, CrO{sub 3}, the octahedrally coordinated compounds Cr(II)-acetate, CrCl{sub 3}, CrF{sub 3}, Cr{sub 2}O{sub 3}, KCr(SO{sub 4}){sub 2} {center_dot} 12H{sub 2}O, CrO{sub 2} and cubic coordinated metallic chromium. In these compounds chromium exhibits a wide range of formal oxidation states (0 to VI). The absorption features in the near edge region are shown to be characteristic of the spatial environment of the absorbing atom. The occurrence of a single pre-edge line easily allows one to distinguish between tetrahedral and octahedral coordination geometry, whereas the energy position of the absorption edge is found to be very sensitive to the valency of the excited chromium atom. Calculations of the ionisation potential of Cr in different oxidation states using the non-relativistic Hartree-Fock method (Froese-Fischer) confirm that the ionisation limit shifts to higher energy with increasing Cr valency. More detailed information on the electronic structure of the different compounds is gained by real-space full multiple scattering calculations using the FEFF8 code.

  7. The influence of coordination geometry and valency on the K-edge absorption near edge spectra of selected chromium compounds

    Science.gov (United States)

    Pantelouris, A.; Modrow, H.; Pantelouris, M.; Hormes, J.; Reinen, D.

    2004-05-01

    X-ray absorption spectra at the chromium K-edge are reported for a number of selected chromium compounds of known chemical structure. The spectra were obtained with use of synchrotron radiation available at the ELectron Stretcher Accelerator ELSA in Bonn. The compounds studied include the tetrahedrally coordinated compounds Ca 2Ge 0.8Cr 0.2O 4, Ba 2Ge 0.1Cr 0.9O 4, Sr 2CrO 4, Ca 2(PO 4) x(CrO 4) 1- xCl ( x=0.25,0.5), Ca 5(CrO 4) 3Cl, CrO 3, the octahedrally coordinated compounds Cr(II)-acetate, CrCl 3, CrF 3, Cr 2O 3, KCr(SO 4) 2 · 12H 2O, CrO 2 and cubic coordinated metallic chromium. In these compounds chromium exhibits a wide range of formal oxidation states (0 to VI). The absorption features in the near edge region are shown to be characteristic of the spatial environment of the absorbing atom. The occurrence of a single pre-edge line easily allows one to distinguish between tetrahedral and octahedral coordination geometry, whereas the energy position of the absorption edge is found to be very sensitive to the valency of the excited chromium atom. Calculations of the ionisation potential of Cr in different oxidation states using the non-relativistic Hartree-Fock method (Froese-Fischer) confirm that the ionisation limit shifts to higher energy with increasing Cr valency. More detailed information on the electronic structure of the different compounds is gained by real-space full multiple scattering calculations using the FEFF8 code.

  8. The pharmacokinetic profile of tamsulosin oral controlled absorption system (OCAS((R)))

    NARCIS (Netherlands)

    Michel, M. C.; Korstanje, C.; Krauwinkel, W.; Kuipers, M.

    2005-01-01

    Context: A new formulation of tamsulosin for the treatment of lower urinary tract symptoms suggestive of benign prostatic hyperplasia (LUTS/BPH) has been developed. This formulation uses the proprietary oral controlled absorption system (OCAS(R)) technology which has the potential to better control

  9. Pharmacokinetics and Pharmacodynamics of Tamsulosin in its Modified-Release and Oral Controlled Absorption System Formulations

    NARCIS (Netherlands)

    Franco-Salinas, Gabriela; de La Rosette, Jean J. M. C. H.; Michel, Martin C.

    2010-01-01

    Tamsulosin is an alpha(1)-adrenoceptor antagonist used for the treatment of lower urinary tract symptoms that are suggestive of benign prostatic hyperplasia. It is mostly used in a modified-release (M R) Formulation. but an oral controlled absorption system (OCAS) and a 'without-water' tablet

  10. Nonlinear absorption of fullerene- and nanotubes-doped liquid crystal systems

    Czech Academy of Sciences Publication Activity Database

    Kamanina, N.; Reshak, Ali H; Vasiliev, P.Y.; Vangonen, A. I.; Studeonov, V. I.; Usanov, Y. E.; Ebothe, J.; Gondek, E.; Wojcik, W.; Danel, A.

    2009-01-01

    Roč. 41, č. 3 (2009), s. 391-394 ISSN 1386-9477 Institutional research plan: CEZ:AV0Z60870520 Keywords : nonlinear absorption properties * organic electrooptical systems * liquid crystal * fullerene s * nanotubes * PVK-derivatives Subject RIV: BO - Biophysics Impact factor: 1.177, year: 2009

  11. Study of an absorption machine for an ammonia-water system ...

    African Journals Online (AJOL)

    This paper deals with Study of an absorption machine for an ammonia-water system decentralized trigeneration. The effects of evaporator, absorber and boiler temperature on the coefficient of performance of this cycle investigate. Simulation results show that with increasing the evaporator and absorber temperature the ...

  12. Mapping Quantitatively Regional Drug Absorption in Canines with IntelliCap System

    NARCIS (Netherlands)

    Becker, D.; Schütz, H.; Beyerbach, A.; Zou, H.; Shimizu, J.; Iordanov, V.P.

    2011-01-01

    Quantitative regional absorption of a drug under development was studied by using the novel IntelliCap system. IntelliCap is an orally swallowable programmable drug delivery capsule and capable of real-time monitoring of physiological conditions (pH, temperature), consequently allowing localization

  13. Nature and statistical properties of quasar associated absorption systems in the XQ-100 Legacy Survey

    DEFF Research Database (Denmark)

    Perrotta, Serena; D'Odorico, Valentina; Prochaska, J. Xavier

    2016-01-01

    We statistically study the physical properties of a sample of narrow absorption line (NAL) systems looking for empirical evidences to distinguish between intrinsic and intervening NALs without taking into account any a priori definition or velocity cut-off. We analyze the spectra of 100 quasars...

  14. Multiuser hybrid switched-selection diversity systems

    KAUST Repository

    Shaqfeh, Mohammad

    2011-09-01

    A new multiuser scheduling scheme is proposed and analyzed in this paper. The proposed system combines features of conventional full-feedback selection-based diversity systems and reduced-feedback switch-based diversity systems. The new hybrid system provides flexibility in trading-off the channel information feedback overhead with the prospected multiuser diversity gains. The users are clustered into groups, and the users\\' groups are ordered into a sequence. Per-group feedback thresholds are used and optimized to maximize the system overall achievable rate. The proposed hybrid system applies switched diversity criterion to choose one of the groups, and a selection criterion to decide the user to be scheduled from the chosen group. Numerical results demonstrate that the system capacity increases as the number of users per group increases, but at the cost of more required feedback messages. © 2011 IEEE.

  15. How to take absorptive surfaces into account when designing outdoor sound reinforcement systems

    DEFF Research Database (Denmark)

    Rasmussen, Karsten bo

    1996-01-01

    When sound reinforcement systems are used outdoors, absorptive surfaces are usually present along the propagation path of the sound. This may lead to a very significant colouration of the spectrum received by the audience. The colouration depends on the location and directivity of the loudspeaker......, the nature of the absorptive surface (eg grass) and the location of the audience. It is discussed how this effect may be calculated and numerical examples are shown. The results show a significant colouration and attenuation of the sound due to grass-covered surfaces....

  16. Efficient atom localization via probe absorption in an inverted-Y atomic system

    Science.gov (United States)

    Wu, Jianchun; Wu, Bo; Mao, Jiejian

    2018-06-01

    The behaviour of atom localization in an inverted-Y atomic system is theoretically investigated. For the atoms interacting with a weak probe field and several orthogonal standing-wave fields, their position information can be obtained by measuring the probe absorption. Compared with the traditional scheme, we couple the probe field to the transition between the middle and top levels. It is found that the probe absorption sensitively depends on the detuning and strength of the relevant light fields. Remarkably, the atom can be localized at a particular position in the standing-wave fields by coupling a microwave field to the transition between the two ground levels.

  17. Portable Instrument to Measure CDOM Light Absorption in Aquatic Systems: WPI Success Story

    Science.gov (United States)

    2001-01-01

    World Precision Instruments, Inc. (WPI), of Sarasota, FL, in collaboration with NASA's John C. Stennis Space Center, has developed an innovative instrument to accurately measure Colored Dissolved Organic Matter (CDOM) absorption in the field. This successful collaboration has culminated in an exciting new device, called the UltraPath, now commercially available through WPI. Traditional methods of measuring absorption of dissolved materials require special handling and storage prior to measurement. Use of laboratory spectrophotometers as the measuring devices have proven time consuming, cumbersome, and delicate to handle. The UltraPath provides a low-cost, highly sensitive, rugged, portable system that is capable of high sensitivity measurements in widely divergent waters.

  18. Ab-sorption machines for heating and cooling in future energy systems - Final report

    Energy Technology Data Exchange (ETDEWEB)

    Tozer, R.; Gustafsson, M.

    2000-12-15

    After the Executive Summary and a brief introductory chapter, Chapter 2, Sorption Technologies for Heating and Cooling in Future Energy Systems, reviews the main types of sorption systems. Chapter 3, Market Segmentation, then considers the major segments of the market including residential, commercial/institutional and industrial, and the types of sorption hardware most suitable to each. The highly important residential and commercial/institutional markets are mostly concerned with air-conditioning of buildings. More applications are identified and discussed for the industrial market, including refrigeration, food-storage cooling, process cooling, and process heating at various temperature ranges from hot water for hand-washing to high-temperature (greater than 130C). Other interesting industrial applications are absorption cooling or heating combined with co-generation, desiccant cooling, gas turbine inlet air cooling, combining absorption chillers with district heating systems, direct-fired absorption heat pumps (AHPs), and a closed greenhouse concept being developed for that economically important sector in the Netherlands. Most of the sorption market at this time comprises direct-fired absorption chillers, or hot water or steam absorption chillers indirectly driven by direct-fired boilers. Throughout the report, this category of absorption chillers is referred to generically as 'direct-fired'. In addition, this report covers absorption (reversible) heat pumps, absorption heat transformers, compression-absorption heat pumps, and adsorption chillers and heat pumps. Adsorption systems together with desiccant systems are also addressed. Chapter 4, Factors Affecting the Market, considers economic, environmental and policy issues. The geographical make-up of the world sorption market is then reviewed, followed by a number of practical operating and control considerations. These include vacuum requirements, crystallisation, corrosion, maintenance, health and

  19. Informing the Selection of Screening Hit Series with in Silico Absorption, Distribution, Metabolism, Excretion, and Toxicity Profiles.

    Science.gov (United States)

    Sanders, John M; Beshore, Douglas C; Culberson, J Christopher; Fells, James I; Imbriglio, Jason E; Gunaydin, Hakan; Haidle, Andrew M; Labroli, Marc; Mattioni, Brian E; Sciammetta, Nunzio; Shipe, William D; Sheridan, Robert P; Suen, Linda M; Verras, Andreas; Walji, Abbas; Joshi, Elizabeth M; Bueters, Tjerk

    2017-08-24

    High-throughput screening (HTS) has enabled millions of compounds to be assessed for biological activity, but challenges remain in the prioritization of hit series. While biological, absorption, distribution, metabolism, excretion, and toxicity (ADMET), purity, and structural data are routinely used to select chemical matter for further follow-up, the scarcity of historical ADMET data for screening hits limits our understanding of early hit compounds. Herein, we describe a process that utilizes a battery of in-house quantitative structure-activity relationship (QSAR) models to generate in silico ADMET profiles for hit series to enable more complete characterizations of HTS chemical matter. These profiles allow teams to quickly assess hit series for desirable ADMET properties or suspected liabilities that may require significant optimization. Accordingly, these in silico data can direct ADMET experimentation and profoundly impact the progression of hit series. Several prospective examples are presented to substantiate the value of this approach.

  20. Selective Two-Photon Absorptive Resonance Femtosecond-Laser Electronic-Excitation Tagging (STARFLEET) Velocimetry in Flow and Combustion Diagnostics

    Science.gov (United States)

    Jiang, Naibo; Halls, Benjamin R.; Stauffer, Hans U.; Roy, Sukesh; Danehy, Paul M.; Gord, James R.

    2016-01-01

    Selective Two-Photon Absorptive Resonance Femtosecond-Laser Electronic-Excitation Tagging (STARFLEET), a non-seeded ultrafast-laser-based velocimetry technique, is demonstrated in reactive and non-reactive flows. STARFLEET is pumped via a two-photon resonance in N2 using 202.25-nm 100-fs light. STARFLEET greatly reduces the per-pulse energy required (30 µJ/pulse) to generate the signature FLEET emission compared to the conventional FLEET technique (1.1 mJ/pulse). This reduction in laser energy results in less energy deposited in the flow, which allows for reduced flow perturbations (reactive and non-reactive), increased thermometric accuracy, and less severe damage to materials. Velocity measurements conducted in a free jet of N2 and in a premixed flame show good agreement with theoretical velocities and further demonstrate the significantly less-intrusive nature of STARFLEET.

  1. Characterization of selective binding of alkali cations with carboxylate by x-ray absorption spectroscopy of liquid microjets

    Energy Technology Data Exchange (ETDEWEB)

    Saykally, Richard J; Uejio, Janel S.; Schwartz, Craig P.; Duffin, Andrew M.; Drisdell, Walter S.; Cohen, Ronald C.; Saykally, Richard J.

    2008-01-08

    We describe an approach for characterizing selective binding between oppositely charged ionic functional groups under biologically relevant conditions. Relative shifts in K-shell x-ray absorption spectra of aqueous cations and carboxylate anions indicate the corresponding binding strengths via perturbations of carbonyl antibonding orbitals. XAS spectra measured for aqueous formate and acetate solutions containing lithium, sodium, and potassium cations reveal monotonically stronger binding of the lighter metals, supporting recent results from simulations and other experiments. The carbon K-edge spectra of the acetate carbonyl feature centered near 290 eV clearly indicate a preferential interaction of sodium versus potassium, which was less apparent with formate. These results are in accord with the Law of Matching Water Affinities, relating relative hydration strengths of ions to their respective tendencies to form contact ion pairs. Density functional theory calculations of K-shell spectra support the experimental findings.

  2. Characterization of selective binding of alkali cations with carboxylate by x-ray absorption spectroscopy of liquid microjets

    International Nuclear Information System (INIS)

    Saykally, Richard J; Uejio, Janel S.; Schwartz, Craig P.; Duffin, Andrew M.; Drisdell, Walter S.; Cohen, Ronald C.; Saykally, Richard J.

    2008-01-01

    We describe an approach for characterizing selective binding between oppositely charged ionic functional groups under biologically relevant conditions. Relative shifts in K-shell x-ray absorption spectra of aqueous cations and carboxylate anions indicate the corresponding binding strengths via perturbations of carbonyl antibonding orbitals. XAS spectra measured for aqueous formate and acetate solutions containing lithium, sodium, and potassium cations reveal monotonically stronger binding of the lighter metals, supporting recent results from simulations and other experiments. The carbon K-edge spectra of the acetate carbonyl feature centered near 290 eV clearly indicate a preferential interaction of sodium versus potassium, which was less apparent with formate. These results are in accord with the Law of Matching Water Affinities, relating relative hydration strengths of ions to their respective tendencies to form contact ion pairs. Density functional theory calculations of K-shell spectra support the experimental findings

  3. High levels of absorption in orientation-unbiased, radio-selected 3CR Active Galaxies

    Science.gov (United States)

    Wilkes, Belinda J.; Haas, Martin; Barthel, Peter; Leipski, Christian; Kuraszkiewicz, Joanna; Worrall, Diana; Birkinshaw, Mark; Willner, Steven P.

    2014-08-01

    A critical problem in understanding active galaxies (AGN) is the separation of intrinsic physical differences from observed differences that are due to orientation. Obscuration of the active nucleus is anisotropic and strongly frequency dependent leading to complex selection effects for observations in most wavebands. These can only be quantified using a sample that is sufficiently unbiased to test orientation effects. Low-frequency radio emission is one way to select a close-to orientation-unbiased sample, albeit limited to the minority of AGN with strong radio emission.Recent Chandra, Spitzer and Herschel observations combined with multi-wavelength data for a complete sample of high-redshift (1half the sample is significantly obscured with ratios of unobscured: Compton thin (22 24.2) = 2.5:1.4:1 in these high-luminosity (log L(0.3-8keV) ~ 44-46) sources. These ratios are consistent with current expectations based on modelingthe Cosmic X-ray Background. A strong correlation with radio orientation constrains the geometry of the obscuring disk/torus to have a ~60 degree opening angle and ~12 degree Compton-thick cross-section. The deduced ~50% obscured fraction of the population contrasts with typical estimates of ~20% obscured in optically- and X-ray-selected high-luminosity samples. Once the primary nuclear emission is obscured, AGN X-ray spectra are frequently dominated by unobscured non-nuclear or scattered nuclear emission which cannot be distinguished from direct nuclear emission with a lower obscuration level unless high quality data is available. As a result, both the level of obscuration and the estimated instrinsic luminosities of highly-obscured AGN are likely to be significantly (*10-1000) underestimated for 25-50% of the population. This may explain the lower obscured fractions reported for optical and X-ray samples which have no independent measure of the AGN luminosity. Correcting AGN samples for these underestimated luminosities would result in

  4. Control Configuration Selection for Multivariable Descriptor Systems

    DEFF Research Database (Denmark)

    Shaker, Hamid Reza; Stoustrup, Jakob

    2012-01-01

    Control configuration selection is the procedure of choosing the appropriate input and output pairs for the design of SISO (or block) controllers. This step is an important prerequisite for a successful industrial control strategy. In industrial practices it is often the case that the system, whi...... is that it can be used to propose a richer sparse or block diagonal controller structure. The interaction measure is used for control configuration selection of the linearized CSTR model with descriptor from....

  5. Hybrid compression/absorption type heat utilization system (eco-energy city project)

    Energy Technology Data Exchange (ETDEWEB)

    Karimata, T.; Susami, S.; Ogawa, Y. [Research and Development Dept., EBARA Corp., Kanagawa pref. (Japan)

    1999-07-01

    This research is intended to develop a 'hybrid compression/absorption type heat utilization system' by combining an absorption process with a compression process in one circulation cycle. This system can produce chilling heat for ice thermal storage by utilizing low-temperature waste heat (lower than 100 C) which is impossible to treat with a conventional absorption chiller. It means that this system will be able to solve the problem of a timing mismatch between waste heat and heat demand. The working fluid used in this proposed system should be suitable for producing ice, be safe, and not damage the ozone layer. In this project, new working fluids were searched as substitutes for the existing H{sub 2}O/LiBr or NH{sub 3}/H{sub 2}O. The interim results of this project in 1997, a testing unit using NH{sub 3}/H{sub 2}O was built for demonstration of the system and evaluation of its characteristics, and R134a/E181 was found to be one of the good working fluid for this system. The COP (ratio of energy of ice produced to electric power provided) of this system using R134a/E181 is expected to achieve 5.5 by computer simulation. The testing unit with this working fluid was built recently and prepared for the tests to confirm the result of the simulation. (orig.)

  6. Thermodynamic performance analysis of gas-fired air-cooled adiabatic absorption refrigeration systems

    International Nuclear Information System (INIS)

    Wang, L.; Chen, G.M.; Wang, Q.; Zhong, M.

    2007-01-01

    In China, the application of small size gas-fired air-cooled absorption refrigeration systems as an alternative for electric compression air conditioning systems has shown broad prospects due to occurrence of electricity peak demand in Chinese big cities and lack of water resources. However, for conventional air-cooled absorption refrigeration systems, it is difficult to enhance the heat and mass transfer process in the falling film absorber, and may cause problems, for example, remarkable increase of pressure, temperature and concentration in the generators, risk of crystallization, acceleration of corrosion, degradation of performance, and so on. This paper presents a gas-fired air-cooled adiabatic absorption refrigeration system using lithium bromide-water solutions as its working fluid, which is designed with a cooling capacity of 16 kW under standard conditions. The system has two new features of waste heat recovery of condensed water from generator and an adiabatic absorber with an air cooler. Performance simulation and characteristic analysis are crucial for the optimal control and reliability of operation in extremely hot climates. A methodology is presented to simulate thermodynamic performance of the system. The influences of outdoor air temperature on operation performances of the system are investigated

  7. Design of absorption system water-ammonia by using solar radiation as thermal source

    Energy Technology Data Exchange (ETDEWEB)

    Cavalcanti, Eduardo J. Cidade; Souza, Luiz Guilherme Meira [Universidade Federal do Rio Grande do Norte (UFRN), Natal, RN (Brazil). Centro de Tecnlogia. Dept. de Engenharia Mecanica], E-mails: educanti@gmail.com, lguilherme@dem.ufrn.br

    2010-07-01

    An absorption refrigeration system with the single effect of par ammonia water with 1.758 kW (1 / 2 RT) cooling capacity was designed. The system was operating under conditions of 5 degree C evaporation and 45 degree C condensation temperature. The absorption system has a heat exchanger to improve performance. The heat source is the cylinder parabolic solar concentrator (CPC). The design of the concentrator was estimated based on experimental data of the pilot plant built in the Solar Energy Laboratory, Federal University of Rio Grande do Norte. The thermodynamic model with heat and mass transfer was made to the project areas of heat exchange (absorber) and consequent construction of the system. The rectifying column was modeling assuming that liquid is in equilibrium with the vapor state in all plate. The results should show the dimensions of the compact and allows a future assessment of the operational cost. (author)

  8. Two-dimensional atom localization via probe absorption in a four-level atomic system

    International Nuclear Information System (INIS)

    Wang Zhi-Ping; Ge Qiang; Ruan Yu-Hua; Yu Ben-Li

    2013-01-01

    We have investigated the two-dimensional (2D) atom localization via probe absorption in a coherently driven four-level atomic system by means of a radio-frequency field driving a hyperfine transition. It is found that the detecting probability and precision of 2D atom localization can be significantly improved via adjusting the system parameters. As a result, our scheme may be helpful in laser cooling or the atom nano-lithography via atom localization

  9. Designing the lithium bromide air conditioning absorption system for a bus

    International Nuclear Information System (INIS)

    Yusoff Ali; Kamaruzzaman Sopian; Hariadi

    2006-01-01

    A system of air-conditioning using Lithium Bromide absorption system is used as an alternative refrigerant that will not pollute the atmosphere. Lithium Bromide is a chemical salt soluble in water. There is a big difference between vapour compression system and LiBr 2 absorption system. The absorption air conditioning system is made of a generator, a condenser, an evaporator and an absorber with necessary pumps and piping. When LiBr 2 solution is heated under low pressure, water will evaporate first, while LiBr 2 will remain in the solution and will become more concentrated. The water is the refrigerant in this system. The generator, where the water is vapourised, is heated using an electric heater or solar energy. The LiBr 2 weak solution under low pressure in the generator is heated and the water evaporate into vapour. The vapour produced is then cooled in the condenser and then expanded into the evaporator. The refrigerant (water) in evaporator change phase from liquid to vapour by absorbing heat from cooling water, which flow in the coil in the evaporator. The chilled water obtained is then pumped into the fan coil, which will be used in conditioning the passenger area of the bus. The water vapour from the evaporator is absorbed into LiBr 2 solution in the absorber, forming a weak solution of LiBr 2 . the weak solution from the absorber is then pumped back to the generator to regenerate. The absorption system does not use compressor, but requires pumps that need lower input power compared to that of a compressor. The system is considered as a new application for the bus. This will have great potential and will be environmentally friendly. The model in this study will be used for calculation of the cooling load for the bus

  10. ORIGINS OF ABSORPTION SYSTEMS OF CLASSICAL NOVA V2659 CYG (NOVA CYG 2014)

    Energy Technology Data Exchange (ETDEWEB)

    Arai, A.; Kawakita, H. [Koyama Astronomical Observatory, Kyoto Sangyo University, Motoyama, Kamigamo, Kita-ku, Kyoto 603-8555 (Japan); Shinnaka, Y. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Tajitsu, A., E-mail: arai6a@cc.kyoto-su.ac.jp [Subaru Telescope, National Astronomical Observatory of Japan, 650 North A’ohoku Place, Hilo, Hawaii 96720 (United States)

    2016-10-10

    We report on high-dispersion spectroscopy results of a classical nova V2659 Cyg (Nova Cyg 2014) that are taken 33.05 days after the V -band maximum. The spectrum shows two distinct blueshifted absorption systems originating from H i, Fe ii, Ca ii, etc. The radial velocities of the absorption systems are −620 km s{sup −1}, and −1100 to −1500 km s{sup −1}. The higher velocity component corresponds to the P-Cygni absorption features frequently observed in low-resolution spectra. Much larger numbers of absorption lines are identified at the lower velocity. These mainly originate from neutral or singly ionized Fe-peak elements (Fe i, Ti ii, Cr ii, etc.). Based on the results of our spectroscopic observations, we discuss the structure of the ejecta of V2659 Cyg. We conclude that the low- and high-velocity components are likely to be produced by the outflow wind and the ballistic nova ejecta, respectively.

  11. Spectral control of an alexandrite laser for an airborne water-vapor differential absorption lidar system

    Science.gov (United States)

    Ponsardin, Patrick; Grossmann, Benoist E.; Browell, Edward V.

    1994-01-01

    A narrow-linewidth pulsed alexandrite laser has been greatly modified for improved spectral stability in an aircraft environment, and its operation has been evaluated in the laboratory for making water-vapor differential absorption lidar measurements. An alignment technique is described to achieve the optimum free spectral range ratio for the two etalons inserted in the alexandrite laser cavity, and the sensitivity of this ratio is analyzed. This technique drastically decreases the occurrence of mode hopping, which is commonly observed in a tunable, two-intracavity-etalon laser system. High spectral purity (greater than 99.85%) at 730 nm is demonstrated by the use of a water-vapor absorption line as a notch filter. The effective cross sections of 760-nm oxygen and 730-nm water-vapor absorption lines are measured at different pressures by using this laser, which has a finite linewidth of 0.02 cm(exp -1) (FWHM). It is found that for water-vapor absorption linewidths greater than 0.04 cm(exp -1) (HWHM), or for altitudes below 10 km, the laser line can be considered monochromatic because the measured effective absorption cross section is within 1% of the calculated monochromatic cross section. An analysis of the environmental sensitivity of the two intracavity etalons is presented, and a closed-loop computer control for active stabilization of the two intracavity etalons in the alexandrite laser is described. Using a water-vapor absorption line as a wavelength reference, we measure a long-term frequency drift (approximately 1.5 h) of less than 0.7 pm in the laboratory.

  12. Synthesis of Hα absorption in old stellar systems: formation of the cluster red sequence by `downsizing'

    Science.gov (United States)

    Smith, Russell J.

    2005-05-01

    We compute population synthesis models for the variation of Hα absorption indices (HαA and HαF), as a function of age and metallicity in old stellar systems. The models are based on the STELIB spectral library of Le Borgne et al., and defined at a resolution of 3Åfull width at half-maximum. Errors in the age and metallicity responses are derived by bootstrap resampling the input measurements on the stellar library. The indices are found to be highly sensitive to age variation, with only moderate response to metallicity. For galaxies uncontaminated by nebular emission, our HαA index is more powerful in breaking the age-metallicity degeneracy than Hβ or HγF. Using a sample of red cluster galaxies from Nelan et al., carefully selected to exclude objects with emission, we find a steep decline of HαA with velocity dispersion (slope -0.75 +/- 0.07Ådex-1). The slope can be translated to constraints on age and metallicity scaling relations, incorporating measurement errors and also the model errors determined from the bootstrap method. If the HαA-σ slope is due only to age, we obtain Age ~σ0.95+/-0.12. Because HαA depends quite weakly on [Fe/H], a metallicity interpretation would require Fe/H ~σ1.2 or steeper. The HαA-σ slope is consistent with the combined age and metallicity scaling relations reported by Nelan et al. from classical Lick indices. The relations obtained by Thomas et al. significantly underpredict the observed slope. The discrepancy could arise from differences in the sample selection. In particular, our sample probes a lower mass range, is not explicitly selected on morphological criteria, and excludes objects significantly bluer than the red sequence. We discuss in detail the impact of emission contamination on the results, and conclude that this effect is unlikely to yield the observed behaviour in the Hα-σ relations. Indeed, similar results are obtained using HαF, despite its different sensitivity to Hα and [NII] emission lines. The

  13. Critical tuning of magnetron sputtering process parameters for optimized solar selective absorption of NiCrO{sub x} cermet coatings on aluminium substrate

    Energy Technology Data Exchange (ETDEWEB)

    Gaouyat, Lucie, E-mail: lucie.gaouyat@fundp.ac.be [Solid State Physics Laboratory, Research Center in Physics of Matter and Radiation (PMR), Facultés Universitaires Notre-Dame de la Paix (FUNDP), 61 rue de Bruxelles, B-5000 Namur (Belgium); Mirabella, Frédéric [CRM Group – AC and CS, 57b boulevard de Colonster, B-4000 Liège (Belgium); Deparis, Olivier [Solid State Physics Laboratory, Research Center in Physics of Matter and Radiation (PMR), Facultés Universitaires Notre-Dame de la Paix (FUNDP), 61 rue de Bruxelles, B-5000 Namur (Belgium)

    2013-04-15

    NiCrO{sub x} ceramic–metal composites (i.e. cermets) exhibit not only oxidation and moisture resistances, which are very important for industrial applications, but also remarkable solar selective absorption properties. In order to reach the best optical performances with only one coating layer, tuning of the magnetron sputtering process parameters (O{sub 2} flow rate, pressure and deposition time) was performed systematically. The process window turned out to be very narrow implying a critical tuning of the parameters. The optimal operating point was determined for a single layer coating of NiCrO{sub x} on an aluminium substrate, leading to a spectrally integrated solar absorption as high as 78%. Among various material properties, the focus was put on the optical reflectance of the coating/substrate system, which was measured by UV–vis–NIR spectrophotometry. Using complex refractive index data from the literature, the theoretical reflectance spectra were calculated and found to be in good agreement with the measurements. Chemical analysis combined with scanning electronic and atomic force microscopies suggested a cermet structure consisting of metallic Ni particles and a compound matrix made of a mixture of chromium oxide, nickel oxide and nickel hydroxide.

  14. Graphical expression of thermodynamic characteristics of absorption process in ammonia-water system

    Directory of Open Access Journals (Sweden)

    Fortelný Zdeněk

    2012-04-01

    Full Text Available The adiabatic sorption is very interesting phenomenon that occurs when vapor of refrigerant is in contact with unsaturated liquid absorbent-refrigerant mixture and exchange of heat is forbid between the system and an environment. This contribution introduces new auxiliary lines that enable correct position determination of the adiabatic sorption process in the p-T-x diagram of ammoniawater system. The presented auxiliary lines were obtained from common functions for fast calculation of water-ammonia system properties. Absorption cycles designers often utilize p-t-x diagrams of working mixtures for first suggestion of new absorption cycles. The p-t-x diagrams enable fast correct determination of saturate states of liquid (and gaseous mixtures of refrigerants and absorbents. The working mixture isn’t only at saturated state during a real working cycle. If we know pressure and temperature of an unsaturated mixture, exact position determination is possible in the p-t-x diagrams too.

  15. Application of a solar refrigeration system by absorption for the air conditioning of buildings

    Energy Technology Data Exchange (ETDEWEB)

    Machielsen, Cees H. M [Delft University of Technology, Mekelweg (Netherlands); Hagendijk, Andre E [Consultancy and Research (Netherlands)

    2000-07-01

    This paper describes the Sofri project, a cooperation between Ceeran Ltd and The Delft University of Technology. The main objective of this project is to develop the necessary knowledge and experience to commercialize solar-assisted air conditioning and dehumidification systems in the Dutch Caribbean. The project is motivated by the present needs of the Dutch Caribbean for renewable energy sources and the fact that the Caribbean has a high and uniform insolation throughout the year. Furthermore, hotels and offices in this area use more than 40% of their energy for air-conditioning purposes. Therefore solar-assisted air conditioning systems are a logic approach in reducing the energy demand and to lower the peak electricity reducing the energy demands for the local power station. Ceeran Ltd has the objective to reach full commercialization of the proposed technologies in the Dutch Caribbean. The research is concentrated on liquid absorption machines and solar collection systems such as flat plates with selective surfaces, heat pipe evacuated tubes flat plate collectors, and Compound Parabolic Concentrators. The first demonstration unit is planned to be installed in an office building in Curacao. The installation consists of a 35 kW LiBr/H{sub 2}O absorption machine driven by 100 m{sup 2} flat pate collectors with a gas backup system. The system will provide comfort air-conditioning for this these type of office buildings during daytime. [Spanish] Este documento describe el proyecto SOFRI, una cooperacion entre Ceeran, Ltd, y la Universidad Tecnologica del Delft. El principal objetivo de este proyecto es el de desarrollar el conocimiento necesario y la experiencia para comercializar los sistemas de aire acondicionado y deshumidificacion ayudados por la energia solar en el Caribe Holandes. Este proyecto ha sido motivado por las actuales necesidades del Caribe Holandes de fuentes de energia renovable y por el hecho de que el Caribe tiene una alta y uniforme insolacion

  16. [Signal analysis and spectrum distortion correction for tunable diode laser absorption spectroscopy system].

    Science.gov (United States)

    Bao, Wei-Yi; Zhu, Yong; Chen, Jun; Chen, Jun-Qing; Liang, Bo

    2011-04-01

    In the present paper, the signal of a tunable diode laser absorption spectroscopy (TDLAS) trace gas sensing system, which has a wavelength modulation with a wide range of modulation amplitudes, is studied based on Fourier analysis method. Theory explanation of spectrum distortion induced by laser intensity amplitude modulation is given. In order to rectify the spectrum distortion, a method of synchronous amplitude modulation suppression by a variable optical attenuator is proposed. To validate the method, an experimental setup is designed. Absorption spectrum measurement experiments on CO2 gas were carried out. The results show that the residual laser intensity modulation amplitude of the experimental system is reduced to -0.1% of its original value and the spectrum distortion improvement is 92% with the synchronous amplitude modulation suppression. The modulation amplitude of laser intensity can be effectively reduced and the spectrum distortion can be well corrected by using the given correction method and system. By using a variable optical attenuator in the TDLAS (tunable diode laser absorption spectroscopy) system, the dynamic range requirements of photoelectric detector, digital to analog converter, filters and other aspects of the TDLAS system are reduced. This spectrum distortion correction method can be used for online trace gas analyzing in process industry.

  17. A thermodynamic evaluation on high pressure condenser of double effect absorption refrigeration system

    International Nuclear Information System (INIS)

    Yılmaz, İbrahim Halil; Saka, Kenan; Kaynakli, Omer

    2016-01-01

    One of the parameters affecting the COP of the absorption system can be considered as the thermal balance between the high pressure condenser (HPC) and the low pressure generator (LPG) since heat rejected from the HPC is utilized as an energy source by the LPG. Condensation of the water vapor in the HPC depends on the heat removal via the LPG. This circumstance is significant for making an appropriate design and a controllable system with high performance in practical applications. For this reason, a thermodynamic analysis for the HPC of a double effect series flow water/lithium bromide absorption refrigeration system was emphasized in this study. A simulation was developed to investigate the energy transfer between the HPC and LPG. The results show that the proper designation of the HPC temperature improves the COP and ECOP due its significant impact, and its value necessarily has to be higher than the outlet temperature of the LPG based on the operating scheme. Furthermore, the COP and ECOP of the absorption system can be raised in the range of 9.72–35.09% in case of 2 °C-temperature increment in the HPC under the described conditions to be applied. - Highlights: • Thermal balance in HPC/LPG unit of a double effect absorption system was studied. • A simulation program was developed and its outputs were validated. • A parametric study was conducted for a wide range of component temperatures. • Proper designation of the HPC temperature improves the COP and ECOP. • The system performance raised 9.72–35.09% by controlling the HPC temperature.

  18. Cavity ring-down spectroscopy (CRDS) system for measuring atmospheric mercury using differential absorption

    Science.gov (United States)

    Pierce, A.; Obrist, D.; Moosmuller, H.; Moore, C.

    2012-04-01

    Atmospheric elemental mercury (Hg0) is a globally pervasive element that can be transported and deposited to remote ecosystems where it poses — particularly in its methylated form — harm to many organisms including humans. Current techniques for measurement of atmospheric Hg0 require several liters of sample air and several minutes for each analysis. Fast-response (i.e., 1 second or faster) measurements would improve our ability to understand and track chemical cycling of mercury in the atmosphere, including high frequency Hg0 fluctuations, sources and sinks, and chemical transformation processes. We present theory, design, challenges, and current results of our new prototype sensor based on cavity ring-down spectroscopy (CRDS) for fast-response measurement of Hg0 mass concentrations. CRDS is a direct absorption technique that implements path-lengths of multiple kilometers in a compact absorption cell using high-reflectivity mirrors, thereby improving sensitivity and reducing sample volume compared to conventional absorption spectroscopy. Our sensor includes a frequency-doubled, dye-laser emitting laser pulses tunable from 215 to 280 nm, pumped by a Q-switched, frequency tripled Nd:YAG laser with a pulse repetition rate of 50 Hz. We present how we successfully perform automated wavelength locking and stabilization of the laser to the peak Hg0 absorption line at 253.65 nm using an external isotopically-enriched mercury (202Hg0) cell. An emphasis of this presentation will be on the implementation of differential absorption measurement whereby measurements are alternated between the peak Hg0 absorption wavelength and a nearby wavelength "off" the absorption line. This can be achieved using a piezo electric tuning element that allows for pulse-by-pulse tuning and detuning of the laser "online" and "offline" of the Hg absorption line, and thereby allows for continuous correction of baseline extinction losses. Unexpected challenges with this approach included

  19. Tamsulosin oral controlled absorption system (OCAS in the treatment of benign prostatic hypertrophy

    Directory of Open Access Journals (Sweden)

    Mischel G Neill

    2008-03-01

    Full Text Available Mischel G Neill, Rohan Shahani, Alexandre R ZlottaDivision of Urology, Department of Surgical Oncology, Princess Margaret and Mount Sinai Hospitals, University of Toronto, Toronto, CanadaAbstract: The efficacy of tamsulosin at the cost of a relatively benign side effect profile has been attributed to receptor selectivity directed at the α1a and α1d adrenergic receptor subtypes. The oral-controlled absorption system (OCAS® represents a drug delivery refinement that incorporates a matrix of gel-forming and gel-enhancing agents to promote a constant drug release independent of environmental food or fluid. There are clinical data to support the concept that drug peaks are lessened and that drug release continues throughout the alimentary tract due to the OCAS formulation. Furthermore this equates with less adverse effects on physiologic parameters. To date however improvements in cardiovascular symptoms such as dizziness, headache and syncope have not been demonstrated in healthy men. Ejaculatory dysfunction appears less problematic with the OCAS preparation. Tamsulosin OCAS may be of greatest benefit to men with cardiovascular co-morbidities taking anti-hypertensive medications that might predispose them to symptomatic hypotensive episodes. It will be necessary to evaluate this group of men more closely in further trials to determine what they stand to gain from changing medications, and then relate this to drug costs to draw a final conclusion as to the place of tamsulosin OCAS in contemporary urological practice.Keywords: lower urinary tract symptoms, benign prostatic hyperplasia, tamsulosin OCAS, safety, efficacy, tolerability

  20. Open absorption system for cooling and air conditioning using membrane contactors - Final report

    Energy Technology Data Exchange (ETDEWEB)

    Conde-Petit, M. [M. Conde Engineering, Zuerich (Switzerland); Weber, R.; Dorer, V. [Swiss Federal Laboratories for Materials Testing and Research (EMPA), Duebendorf (Switzerland)

    2008-07-01

    Air conditioning systems based upon the open absorption principle, essentially an absorption device operating at atmospheric pressure, have been proposed and investigated at many instances in the past eighty years. Their potential for improving energy efficiency is clearly recognized in the earliest research reports. By the mid 1950ies, solar thermal energy was being applied to drive open absorption-based air conditioning systems. For several reasons, however, the open absorption technology was not mature enough to take place in the mainstream. In the past two decades, vigorous efforts have been undertaken to reverse this situation, but success continued to elude, despite the fact that the main problems, such as corrosion, aerosols in the supply air, etc., have been identified. This report details the work and the main results from the MemProDEC Project. In this project innovative solutions were proposed, and successfully investigated, for the corrosion problem and the improvement of efficiency of the absorption process, in particular a new method to cool a very compact absorber. The practically uniform flow distribution for all three streams in the absorber (air, water and desiccant) warrants the contact of the air to be dehumidified with the desiccant over the whole surface of exchange (across a porous membrane). This, together with the cooling with water in counter flow to the air, are the key factors for the excellent effectiveness of the absorber. As the results show, the dehydration effectiveness of the prototype absorber is up to 150 % higher than that previously obtained by others. The solutions developed for compactness and modularity represent an important step in the way to flexible manufacturing, i.e. using a single element size to assemble autonomous air handling units of various nominal capacities. And although the manufacturing methods of the individual elements require improvement, namely by avoiding adhesive bonding, the choice of materials and the

  1. Energy and exergy analysis of a double effect absorption refrigeration system based on different heat sources

    International Nuclear Information System (INIS)

    Kaynakli, Omer; Saka, Kenan; Kaynakli, Faruk

    2015-01-01

    Highlights: • Energy and exergy analysis was performed on double effect series flow absorption refrigeration system. • The refrigeration system runs on various heat sources such as hot water, hot air and steam. • A comparative analysis was carried out on these heat sources in terms of exergy destruction and mass flow rate of heat source. • The effect of heat sources on the exergy destruction of high pressure generator was investigated. - Abstract: Absorption refrigeration systems are environmental friendly since they can utilize industrial waste heat and/or solar energy. In terms of heat source of the systems, researchers prefer one type heat source usually such as hot water or steam. Some studies can be free from environment. In this study, energy and exergy analysis is performed on a double effect series flow absorption refrigeration system with water/lithium bromide as working fluid pair. The refrigeration system runs on various heat sources such as hot water, hot air and steam via High Pressure Generator (HPG) because of hot water/steam and hot air are the most common available heat source for absorption applications but the first law of thermodynamics may not be sufficient analyze the absorption refrigeration system and to show the difference of utilize for different type heat source. On the other hand operation temperatures of the overall system and its components have a major effect on their performance and functionality. In this regard, a parametric study conducted here to investigate this effect on heat capacity and exergy destruction of the HPG, coefficient of performance (COP) of the system, and mass flow rate of heat sources. Also, a comparative analysis is carried out on several heat sources (e.g. hot water, hot air and steam) in terms of exergy destruction and mass flow rate of heat source. From the analyses it is observed that exergy destruction of the HPG increases at higher temperature of the heat sources, condenser and absorber, and lower

  2. Determining CDOM Absorption Spectra in Diverse Aquatic Environments Using a Multiple Pathlength, Liquid Core Waveguide System

    Science.gov (United States)

    Miller, Richard L.; Belz, Mathias; DelCastillo, Carlos; Trzaska, Rick

    2001-01-01

    We evaluated the accuracy, sensitivity and precision of a multiple pathlength, liquid core waveguide (MPLCW) system for measuring colored dissolved organic matter (CDOM) absorption in the UV-visible spectral range (370-700 nm). The MPLCW has four optical paths (2.0, 9.8, 49.3, and 204 cm) coupled to a single Teflon AF sample cell. Water samples were obtained from inland, coastal and ocean waters ranging in salinity from 0 to 36 PSU. Reference solutions for the MPLCW were made having a refractive index of the sample. CDOM absorption coefficients, aCDOM, and the slope of the log-linearized absorption spectra, S, were compared with values obtained using a dual-beam spectrophotometer. Absorption of phenol red secondary standards measured by the MPLCW at 558 nm were highly correlated with spectrophotometer values and showed a linear response across all four pathlengths. Values of aCDOM measured using the MPLCW were virtually identical to spectrophotometer values over a wide range of concentrations. The dynamic range of aCDOM for MPLCW measurements was 0.002 - 231.5 m-1. At low CDOM concentrations spectrophotometric aCDOM were slightly greater than MPLCW values and showed larger fluctuations at longer wavelengths due to limitations in instrument precision. In contrast, MPLCW spectra followed an exponential to 600 nm for all samples.

  3. Effect of resin system on the mechanical properties and water absorption of kenaf fibre reinforced laminates

    International Nuclear Information System (INIS)

    Rassmann, S.; Paskaramoorthy, R.; Reid, R.G.

    2011-01-01

    The objective of this study is to compare the mechanical and water absorption properties of kenaf (Hibiscus cannabinus L.) fibre reinforced laminates made of three different resin systems. The use of different resin systems is considered so that potentially complex and expensive fibre treatments are avoided. The resin systems used include a polyester, a vinyl ester and an epoxy. Laminates of 15%, 22.5% and 30% fibre volume fraction were manufactured by resin transfer moulding. The laminates were tested for strength and modulus under tensile and flexural loading. Additionally, tests were carried out on laminates to determine the impact energy, impact strength and water absorption. The results revealed that properties were affected in markedly different ways by the resin system and the fibre volume fraction. Polyester laminates showed good modulus and impact properties, epoxy laminates displayed good strength values and vinyl ester laminates exhibited good water absorption characteristics. Scanning electron microscope studies show that epoxy laminates fail by fibre fracture, polyester laminates by fibre pull-out and vinyl ester laminates by a combination of the two. A comparison between kenaf and glass laminates revealed that the specific tensile and flexural moduli of both laminates are comparable at the volume fraction of 15%. However, glass laminates have much better specific properties than the kenaf laminates at high fibre volume fractions for all three resins used.

  4. Tunable Absorption System based on magnetorheological elastomers and Halbach array: design and testing

    Energy Technology Data Exchange (ETDEWEB)

    Bocian, Mirosław; Kaleta, Jerzy; Lewandowski, Daniel, E-mail: daniel.lewandowski@pwr.edu.pl; Przybylski, Michał

    2017-08-01

    Highlights: • Construction of a Tunable Absorption System incorporating MRE has been done. • For system control by magnetic field a double circular Halbach array has been used. • Significant changes of the TSAs natural frequency and damping has been obtained. - Abstract: In this paper, the systematic design, construction and testing of a Tunable Absorption System (TAS) incorporating magnetorheological elastomer (MRE) has been investigated. The TAS has been designed for energy absorption and mitigation of vibratory motions from an impact excitation. The main advantage of the designed TAS is that it has the ability to change and adapt to working conditions. Tunability can be realised through a change in the magnetic field caused by the change of an internal arrangement of permanent magnets within a double dipolar circular Halbach array. To show the capabilities of the tested system, experiments based on an impulse excitation have been performed. Significant changes of the TASs natural frequency and damping characteristics have been obtained. By incorporating magnetic tunability within the TAS a significant qualitative and quantitative change in the devices mechanical properties and performance were obtained.

  5. The importance of the ammonia purification process in ammonia-water absorption systems

    International Nuclear Information System (INIS)

    Fernandez-Seara, Jose; Sieres, Jaime

    2006-01-01

    Practical experience in working with ammonia-water absorption systems shows that the ammonia purification process is a crucial issue in order to obtain an efficient and reliable system. In this paper, the detrimental effects of the residual water content in the vapour refrigerant are described and quantified based on the system design variables that determine the effectiveness of the purification process. The study has been performed considering a single stage system with a distillation column with complete condensation. The ammonia purification effectiveness of the column is analysed in terms of the efficiencies in the stripping and rectifying sections and the reflux ratio. By varying the efficiencies from 0 to 1, systems with neither the rectifying nor stripping section, with either the rectifying or stripping section, or with both sections can be considered. The impact of the ammonia purification process on the absorption system performance is studied based on the column efficiencies and reflux ratio; and its effects on refrigerant concentration, system COP, system pressures and main system mass flow rates and concentrations are analysed. When the highest efficiency rectifying sections are used a combination of generation temperature and reflux ratio which leads to optimum COP values is found. The analysis covers different operating conditions with air and water cooled systems from refrigeration to air conditioning applications by changing the evaporation temperature. The importance of rectification in each kind of application is evaluated

  6. Selecting RMF Controls for National Security Systems

    Energy Technology Data Exchange (ETDEWEB)

    Witzke, Edward L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-08-01

    In 2014, the United States Department of Defense started tra nsitioning the way it performs risk management and accreditation of informatio n systems to a process entitled Risk Management Framework for DoD Information Technology or RMF for DoD IT. There are many more security and privacy contro ls (and control enhancements) from which to select in RMF, than there w ere in the previous Information Assurance process. This report is an attempt t o clarify the way security controls and enhancements are selected. After a brief overview and comparison of RMF for DoD I T with the previously used process, this report looks at the determination of systems as National Security Systems (NSS). Once deemed to be an NSS, this report addr esses the categorization of the information system with respect to impact level s of the various security objectives and the selection of an initial baseline o f controls. Next, the report describes tailoring the controls through the use of overl ays and scoping considerations. Finally, the report discusses organizatio n-defined values for tuning the security controls to the needs of the information system.

  7. Selective evolutionary generation systems: Theory and applications

    Science.gov (United States)

    Menezes, Amor A.

    This dissertation is devoted to the problem of behavior design, which is a generalization of the standard global optimization problem: instead of generating the optimizer, the generalization produces, on the space of candidate optimizers, a probability density function referred to as the behavior. The generalization depends on a parameter, the level of selectivity, such that as this parameter tends to infinity, the behavior becomes a delta function at the location of the global optimizer. The motivation for this generalization is that traditional off-line global optimization is non-resilient and non-opportunistic. That is, traditional global optimization is unresponsive to perturbations of the objective function. On-line optimization methods that are more resilient and opportunistic than their off-line counterparts typically consist of the computationally expensive sequential repetition of off-line techniques. A novel approach to inexpensive resilience and opportunism is to utilize the theory of Selective Evolutionary Generation Systems (SECS), which sequentially and probabilistically selects a candidate optimizer based on the ratio of the fitness values of two candidates and the level of selectivity. Using time-homogeneous, irreducible, ergodic Markov chains to model a sequence of local, and hence inexpensive, dynamic transitions, this dissertation proves that such transitions result in behavior that is called rational; such behavior is desirable because it can lead to both efficient search for an optimizer as well as resilient and opportunistic behavior. The dissertation also identifies system-theoretic properties of the proposed scheme, including equilibria, their stability and their optimality. Moreover, this dissertation demonstrates that the canonical genetic algorithm with fitness proportional selection and the (1+1) evolutionary strategy are particular cases of the scheme. Applications in three areas illustrate the versatility of the SECS theory: flight

  8. Connecting the Interstellar Gas and Dust Properties in Distant Galaxies Using Quasar Absorption Systems

    Science.gov (United States)

    Aller, Monique C.; Dwek, Eliahu; Kulkarni, Varsha P.; York, Donald G.; Welty, Daniel E.; Vladilo, Giovanni; Som, Debopam; Lackey, Kyle; Dwek, Eli; Beiranvand, Nassim; hide

    2016-01-01

    Gas and dust grains are fundamental components of the interstellar medium and significantly impact many of the physical processes driving galaxy evolution, such as star-formation, and the heating, cooling, and ionization of the interstellar material. Quasar absorption systems (QASs), which trace intervening galaxies along the sightlines to luminous quasars, provide a valuable tool to directly study the properties of the interstellar gas and dust in distant, normal galaxies. We have established the presence of silicate dust grains in at least some gas-rich QASs, and find that they exist at higher optical depths than expected for diffuse gas in the Milky Way. Differences in the absorption feature shapes additionally suggest variations in the silicate dust grain properties, such as in the level of grain crystallinity, from system-to-system. We present results from a study of the gas and dust properties of QASs with adequate archival IR data to probe the silicate dust grain properties. We discuss our measurements of the strengths of the 10 and 18 micron silicate dust absorption features in the QASs, and constraints on the grain properties (e.g., composition, shape, crystallinity) based on fitted silicate profile templates. We investigate correlations between silicate dust abundance, reddening, and gas metallicity, which will yield valuable insights into the history of star formation and chemical enrichment in galaxies.

  9. Simultaneous multi-element atomic absorption system using photodiode array detector

    International Nuclear Information System (INIS)

    Tong, S.L.; Chin, K.S.

    1994-01-01

    A photodiode array (PDA) detector-multichannel analyser (MCA) system has been coupled to a flame and a graphite furnace atomiser and tested for simultaneous multielement atomic absorption analysis. Multielement hollow cathode lamps (HCL) are used as light source. Spectral lines are dispersed through a spectrograph with triple gratings and detected by a 25.4 mm PDA detector consisting of 1024 elements. The optical MCA system is capable of recording multiple spectra spanned by the spectrograph/PDA. The transmitted intensity spectra obtained for the standard and analyte solutions during flame or graphite furnace atomisation are converted to absorbance spectra using the MCA software provided. Results from the comparison studies show that the linear range and sensitivities for Ni-Co-Fe and Cu-Cr obtained from the simultaneous measurements are within the same order of magnitudes as those from conventional single element determinations using photomultiplier tube detection. The study also shows that non-atomic absorption can be readily corrected by a two-line method where non-atomic absorption lines can be chosen from the spectra recorded simultaneously. The proposed system has been evaluated for the determination of trace elements using NBS standard reference water SRM 1643b

  10. Triple-effect absorption refrigeration system with double-condenser coupling

    Science.gov (United States)

    DeVault, Robert C.; Biermann, Wendell J.

    1993-01-01

    A triple effect absorption refrigeration system is provided with a double-condenser coupling and a parallel or series circuit for feeding the refrigerant-containing absorbent solution through the high, medium, and low temperature generators utilized in the triple-effect system. The high temperature condenser receiving vaporous refrigerant from the high temperature generator is double coupled to both the medium temperature generator and the low temperature generator to enhance the internal recovery of heat within the system and thereby increase the thermal efficiency thereof.

  11. Evaluation of trigeneration system using microturbine, ammonia-water absorption chiller, and a heat recovery boiler

    Energy Technology Data Exchange (ETDEWEB)

    Preter, Felipe C.; Rocha, Marcelo S.; Simoes-Moreira, Jose Roberto [SISEA - Alternative Energy Systems Lab. Dept. of Mechanical Engineering. University of Sao Paulo (EP/USP), SP (Brazil)], e-mails: felipe.preter@poli.usp.br, msrocha@poli.usp.br, jrsimoes@usp.br; Andreos, Ronaldo [COMGAS - Companhia de Gas de Sao Paulo, SP (Brazil)], e-mail: randreos@comgas.com.br

    2010-07-01

    In this work, a CCHP or tri generation system has been projected, mounted, and tested in laboratory, combining a microturbine for power generation, a heat recovery boiler for hot water production, and an ammonia water absorption chiller for chilled water production. The project was motivated by the large practical applications of this kind of energy recovery system in commerce, and industry, and, in general, more than 85% of the energy source is used as power, hot water, and cold water. In the first part, the trigeneration system theoretical model is detailed, and in the second part, experimental results are presented for different operation conditions. (author)

  12. Trigeneration System Based on Municipal Waste Gasification, Fuel Cell and an Absorption Chiller

    DEFF Research Database (Denmark)

    Katsaros, Giannis; Nguyen, Tuong-Van; Rokni, Masoud

    2016-01-01

    of a specific building is also investigated and the system can fully meet the electricity and cooling demands, whereas the heat needs can be satisfied only up to 55%. Moreover, assuming 20 years of operation, the payback period is 4.3 years and the net present value exceeds 5 MEUR.......The present work focuses on the design of a novel tri-generation system based on municipal solid wastes gasification, solid oxide fuel cell and an ammonia-water absorption chiller. Trigeneration systems can be implemented in buildings such as hospitals, where there is a continuous and large demand...

  13. The Mean Metal-line Absorption Spectrum of Damped Ly α Systems in BOSS

    Energy Technology Data Exchange (ETDEWEB)

    Mas-Ribas, Lluís [Institute of Theoretical Astrophysics, University of Oslo, Postboks 1029, NO-0315 Oslo (Norway); Miralda-Escudé, Jordi; Pérez-Ràfols, Ignasi; Arinyo-i-Prats, Andreu [Institut de Ciències del Cosmos, Universitat de Barcelona (UB-IEEC), Barcelona E-08028, Catalonia (Spain); Noterdaeme, Pasquier; Petitjean, Patrick [Institut d’Astrophysique de Paris, UPMC and CNRS, UMR7095 98bis Boulevard Arago, F-75014—Paris (France); Schneider, Donald P. [Department of Astronomy and Astrophysics, The Pennsylvania State University, University Park, PA 16802 (United States); York, Donald G. [Department of Astronomy and Astrophysics and the Enrico Fermi Institute, University of Chicago, 5640 South Ellis Avenue, Chicago, IL 60637 (United States); Ge, Jian, E-mail: l.m.ribas@astro.uio.no [Department of Astronomy, University of Florida, Bryant Space Science Center, Gainesville, FL 32611-2055 (United States)

    2017-09-01

    We study the mean absorption spectrum of the Damped Ly α (DLA) population at z ∼ 2.6 by stacking normalized, rest-frame-shifted spectra of ∼27,000 DLA systems from the DR12 of the Baryon Oscillation Spectroscopic Survey (BOSS)/SDSS-III. We measure the equivalent widths of 50 individual metal absorption lines in five intervals of DLA hydrogen column density, five intervals of DLA redshift, and overall mean equivalent widths for an additional 13 absorption features from groups of strongly blended lines. The mean equivalent width of low-ionization lines increases with N {sub H} {sub i}, whereas for high-ionization lines the increase is much weaker. The mean metal line equivalent widths decrease by a factor ∼1.1–1.5 from z ∼ 2.1 to z ∼ 3.5, with small or no differences between low- and high-ionization species. We develop a theoretical model, inspired by the presence of multiple absorption components observed in high-resolution spectra, to infer mean metal column densities from the equivalent widths of partially saturated metal lines. We apply this model to 14 low-ionization species and to Al iii, S iii, Si iii, C iv, Si iv, N v, and O vi. We use an approximate derivation for separating the equivalent width contributions of several lines to blended absorption features, and infer mean equivalent widths and column densities from lines of the additional species N i, Zn ii, C ii*, Fe iii, and S iv. Several of these mean column densities of metal lines in DLAs are obtained for the first time; their values generally agree with measurements of individual DLAs from high-resolution, high signal-to-noise ratio spectra when they are available.

  14. Experimental assessment of an absorption cooling system operating with the ammonia/lithium nitrate mixture

    International Nuclear Information System (INIS)

    Hernández-Magallanes, J.A.; Domínguez-Inzunza, L.A.; Gutiérrez-Urueta, G.; Soto, P.; Jiménez, C.; Rivera, W.

    2014-01-01

    This paper reports the experimental results of a single effect absorption cooling system of 3 kW of nominal cooling capacity operating with ammonia–lithium nitrate solution. The system was designed and built in the Instituto de Energías Renovables of the Universidad Nacional Autónoma de México and can be used for food conservation or air conditioning. The absorber and generator are falling film heat exchangers. The condenser, evaporator and solution heat exchanger are compact plate heat exchangers. The heat was supplied to the generator at temperatures between 85 °C and 105 °C, while the cooling water temperatures to remove the heat produced during the condensation and absorption varied between 18 °C and 36 °C. The results showed that the system can produce up to 2.7 kW of cooling capacity at heating water temperatures of 95 °C and can achieve evaporator temperatures as low as 1 °C. The experimental coefficients of performance varied between 0.45 and 0.70. Because of the developed system do not need a rectifier and reasonable good coefficients of performance were achieved, the developed system seems to be a good alternative to be used for food conservation or air conditioning. - Highlights: • An absorption cooling system was developed using NH 3 –LiNO 3 . • The achieved COP (coefficients of performance) are the highest reported for a system using NH 3 –LiNO 3 . • Evaporator temperatures as low as 1 °C were achieved. • COP varied between 0.45 and 0.7. • The developed system seems to be a good alternative for food conservation and air conditioning

  15. Optimal Sensor Selection for Health Monitoring Systems

    Science.gov (United States)

    Santi, L. Michael; Sowers, T. Shane; Aguilar, Robert B.

    2005-01-01

    Sensor data are the basis for performance and health assessment of most complex systems. Careful selection and implementation of sensors is critical to enable high fidelity system health assessment. A model-based procedure that systematically selects an optimal sensor suite for overall health assessment of a designated host system is described. This procedure, termed the Systematic Sensor Selection Strategy (S4), was developed at NASA John H. Glenn Research Center in order to enhance design phase planning and preparations for in-space propulsion health management systems (HMS). Information and capabilities required to utilize the S4 approach in support of design phase development of robust health diagnostics are outlined. A merit metric that quantifies diagnostic performance and overall risk reduction potential of individual sensor suites is introduced. The conceptual foundation for this merit metric is presented and the algorithmic organization of the S4 optimization process is described. Representative results from S4 analyses of a boost stage rocket engine previously under development as part of NASA's Next Generation Launch Technology (NGLT) program are presented.

  16. NLP model based thermoeconomic optimization of vapor compression–absorption cascaded refrigeration system

    International Nuclear Information System (INIS)

    Jain, Vaibhav; Sachdeva, Gulshan; Kachhwaha, S.S.

    2015-01-01

    Highlights: • It addresses the size and cost estimation of cascaded refrigeration system. • Cascaded system is a promising decarburizing and energy efficient technology. • Second law analysis is carried out with modified Gouy-Stodola equation. • The total annual cost of plant operation is optimized in present work. - Abstract: This paper addresses the size and cost estimation of vapor compression–absorption cascaded refrigeration system (VCACRS) for water chilling application taking R410a and water–LiBr as refrigerants in compression and absorption section respectively which can help the design engineers in manufacturing and experimenting on such kind of systems. The main limitation in the practical implementation of VCACRS is its size and cost which are optimized in the present work by implementing Direct Search Method in non-linear programming (NLP) mathematical model of VCACRS. The main objective of optimization is to minimize the total annual cost of system which comprises of costs of exergy input and capital costs in monetary units. The appropriate set of decision variables (temperature of evaporator, condenser, generator, absorber, cascade condenser, degree of overlap and effectiveness of solution heat exchanger) minimizes the total annual cost of VCACRS by 11.9% with 22.4% reduction in investment cost at the base case whereas the same is reduced by 7.5% with 11.7% reduction in investment cost with reduced rate of interest and increased life span and period of operation. Optimization results show that the more investment cost in later case is well compensated through the performance and operational cost of the system. In the present analysis, optimum cascade condensing temperature is a strong function of period of operation and capital recovery factor. The cascading of compression and absorption systems becomes attractive for lower rate of interest and increase life span and operational period

  17. Experimental assessment of an absorption cooling system utilizing a falling film absorber and generator

    International Nuclear Information System (INIS)

    Domínguez-Inzunza, L.A.; Hernández-Magallanes, J.A.; Soto, P.; Jiménez, C.; Gutiérrez-Urueta, G.; Rivera, W.

    2016-01-01

    Highlights: • A new prototype of an absorption cooling system using NH_3/LiNO_3 was developed. • Falling films shell and tubes heat exchangers were used as absorber and generator. • Evaporator temperatures as low as 4 °C were achieved. • The COP varied between 0.27 and 0.62 depending on the system temperatures. • A flow recirculation in the absorber was implemented showing an increase in COP. - Abstract: This study presents the results of the evaluation of an ammonia/lithium nitrate absorption cooling system. The generator and the absorber are shell and tubes falling film heat exchangers while the rest of the components are compact plate heat exchangers. A parametric study was carried out in order to determine the coefficients of performance and cooling capacities at different operating conditions. Also, an analysis was carried out to determine the influence of the absorber solution recirculation on the system performance. The generator temperatures varied between 80 °C and 100 °C, while the cooling water temperatures varied from 20 °C to 34 °C. Cooling capacities up to 4.5 kW and evaporator temperatures as low as 4 °C were achieved with the system. The internal coefficients of performance varied between 0.3 and 0.62 depending on the system operating temperatures. The system also showed good stability and repeatability.

  18. Species selective preconcentration and quantification of gold nanoparticles using cloud point extraction and electrothermal atomic absorption spectrometry.

    Science.gov (United States)

    Hartmann, Georg; Schuster, Michael

    2013-01-25

    The determination of metallic nanoparticles in environmental samples requires sample pretreatment that ideally combines pre-concentration and species selectivity. With cloud point extraction (CPE) using the surfactant Triton X-114 we present a simple and cost effective separation technique that meets both criteria. Effective separation of ionic gold species and Au nanoparticles (Au-NPs) is achieved by using sodium thiosulphate as a complexing agent. The extraction efficiency for Au-NP ranged from 1.01 ± 0.06 (particle size 2 nm) to 0.52 ± 0.16 (particle size 150 nm). An enrichment factor of 80 and a low limit of detection of 5 ng L(-1) is achieved using electrothermal atomic absorption spectrometry (ET-AAS) for quantification. TEM measurements showed that the particle size is not affected by the CPE process. Natural organic matter (NOM) is tolerated up to a concentration of 10 mg L(-1). The precision of the method expressed as the standard deviation of 12 replicates at an Au-NP concentration of 100 ng L(-1) is 9.5%. A relation between particle concentration and the extraction efficiency was not observed. Spiking experiments showed a recovery higher than 91% for environmental water samples. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Radiation induced in-situ cationic polymerization of polystyrene organogel for selective absorption of cholorophenols from petrochemical wastewater.

    Science.gov (United States)

    Ghobashy, Mohamed M; Younis, Sherif A; Elhady, Mohamed A; Serp, Philippe

    2018-03-15

    A new in-situ cationic polymerization was performed to synthesize a cross-linked (91%) polystyrene (PS) organogel through tetrachloroethylene radiolysis assisted by 60 Co gamma rays. Hoernschemeyer diagram and swelling capacity test show a better selectivity of PS organogel to chlorinated molecules compared to ester, hydrocarbons and alcohols organic molecules by 80-184 folds. Response surface modeling (RSM) of CPs (2,4,6-trichlorophenol) sorption from artificial wastewater confirm superiority of PS organogel to absorb 1746 μmol CPs/g (∼345 mg CPs/g) at broad pH (4-10) and temperature (25-45 °C). Based on ANOVA statistic, simulated CPs absorption model onto PS organogel was successfully developed, with accuracy of prediction of R 2 ≈ R Adj 2 of 0.991-0.995 and lower coefficient of variation of 2.73% with F model of 611.4 at p 99%) by non-covalent and/or dispersive interaction mechanisms with a well-term reusability and good stability up to 5 cycles. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Analysis of a multicomponent gas absorption system with carrier gas coabsorption

    International Nuclear Information System (INIS)

    Merriman, J.R.

    1975-03-01

    Conventional integrated versions of the packed gas absorber design equations do not account for significant coabsorption of the carrier gas along with the dilute transferring species. These equations, as a result, also neglect the relationship between dilute component transfer and carrier gas coabsorption. In the absorption of Kr and Xe from various carrier gases, using CCl 2 F 2 as the process solvent, carrier coabsorption is substantial. Consequently, a design package was developed to deal with multicomponent gas absorption in systems characterized by carrier gas coabsorption. Developed within the general film theory framework, the basic feature of this design approach is a view of dilute component mass-transfer as a conventional diffusive transfer superimposed on a net flux caused by carrier absorption. Other supporting elements of the design package include predictive techniques for various fluid properties, estimating procedures for carrier gas equilibrium constants, and correlations for carrier gas and dilute gas mass-transfer coefficients. When applied to systems using CCl 2 F 2 as the solvent; He, N 2 , air, or Ar as the carrier gas; and Kr or Xe as the dilute gas; the design approach gave good results, even when extended to conditions well beyond those of its development. (U.S.)

  1. Dynamic investigation of the diffusion absorption refrigeration system NH3-H2O-H2

    Directory of Open Access Journals (Sweden)

    Mohamed Izzedine Serge Adjibade

    2017-09-01

    Full Text Available This paper reports on a numerical and experimental study of a diffusion absorption refrigerator. The performance of the system is examined by computer simulation using MATLAB software and Engineering Equations Solver. A dynamic model is developed for each component of the system and solved numerically in order to predict the transient state of the diffusion absorption refrigeration. The experiment set included 0.04 m3 commercial absorption diffusion refrigerator working with the ammonia-water-hydrogen (NH3-H2O-H2 solution. The transient numerical results were validated with the experimental data. The investigations are focused on the dynamic profile of the temperature of each component. The results obtained agree with the experiment; the relative error between numerical and experimental models doesn’t exceed 15% for all temperatures of each component. The increase of the average ambient temperature from 23.04 °C to 32.56 °C causes an increase of the condensation temperature from 29.46 °C to 37.51 °C, and the best evaporation temperature obtained was 3 °C, with an ambient temperature of 23.04 °C. The results show that a minimum starting temperature of 152 °C and 63.8 W electric power are required to initiate the decrease of evaporation temperature.

  2. Species selective preconcentration and quantification of gold nanoparticles using cloud point extraction and electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Hartmann, Georg, E-mail: georg.hartmann@tum.de [Department of Chemistry, Technische Universitaet Muenchen, 85748 Garching (Germany); Schuster, Michael, E-mail: michael.schuster@tum.de [Department of Chemistry, Technische Universitaet Muenchen, 85748 Garching (Germany)

    2013-01-25

    Highlights: Black-Right-Pointing-Pointer We optimized cloud point extraction and ET-AAS parameters for Au-NPs measurement. Black-Right-Pointing-Pointer A selective ligand (sodium thiosulphate) is introduced for species separation. Black-Right-Pointing-Pointer A limit of detection of 5 ng Au-NP per L is achieved for aqueous samples. Black-Right-Pointing-Pointer Measurement of samples with high natural organic mater content is possible. Black-Right-Pointing-Pointer Real water samples including wastewater treatment plant effluent were analyzed. - Abstract: The determination of metallic nanoparticles in environmental samples requires sample pretreatment that ideally combines pre-concentration and species selectivity. With cloud point extraction (CPE) using the surfactant Triton X-114 we present a simple and cost effective separation technique that meets both criteria. Effective separation of ionic gold species and Au nanoparticles (Au-NPs) is achieved by using sodium thiosulphate as a complexing agent. The extraction efficiency for Au-NP ranged from 1.01 {+-} 0.06 (particle size 2 nm) to 0.52 {+-} 0.16 (particle size 150 nm). An enrichment factor of 80 and a low limit of detection of 5 ng L{sup -1} is achieved using electrothermal atomic absorption spectrometry (ET-AAS) for quantification. TEM measurements showed that the particle size is not affected by the CPE process. Natural organic matter (NOM) is tolerated up to a concentration of 10 mg L{sup -1}. The precision of the method expressed as the standard deviation of 12 replicates at an Au-NP concentration of 100 ng L{sup -1} is 9.5%. A relation between particle concentration and the extraction efficiency was not observed. Spiking experiments showed a recovery higher than 91% for environmental water samples.

  3. Species selective preconcentration and quantification of gold nanoparticles using cloud point extraction and electrothermal atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Hartmann, Georg; Schuster, Michael

    2013-01-01

    Highlights: ► We optimized cloud point extraction and ET-AAS parameters for Au-NPs measurement. ► A selective ligand (sodium thiosulphate) is introduced for species separation. ► A limit of detection of 5 ng Au-NP per L is achieved for aqueous samples. ► Measurement of samples with high natural organic mater content is possible. ► Real water samples including wastewater treatment plant effluent were analyzed. - Abstract: The determination of metallic nanoparticles in environmental samples requires sample pretreatment that ideally combines pre-concentration and species selectivity. With cloud point extraction (CPE) using the surfactant Triton X-114 we present a simple and cost effective separation technique that meets both criteria. Effective separation of ionic gold species and Au nanoparticles (Au-NPs) is achieved by using sodium thiosulphate as a complexing agent. The extraction efficiency for Au-NP ranged from 1.01 ± 0.06 (particle size 2 nm) to 0.52 ± 0.16 (particle size 150 nm). An enrichment factor of 80 and a low limit of detection of 5 ng L −1 is achieved using electrothermal atomic absorption spectrometry (ET-AAS) for quantification. TEM measurements showed that the particle size is not affected by the CPE process. Natural organic matter (NOM) is tolerated up to a concentration of 10 mg L −1 . The precision of the method expressed as the standard deviation of 12 replicates at an Au-NP concentration of 100 ng L −1 is 9.5%. A relation between particle concentration and the extraction efficiency was not observed. Spiking experiments showed a recovery higher than 91% for environmental water samples.

  4. Space Launch System Base Heating Test: Tunable Diode Laser Absorption Spectroscopy

    Science.gov (United States)

    Parker, Ron; Carr, Zak; MacLean, Mathew; Dufrene, Aaron; Mehta, Manish

    2016-01-01

    This paper describes the Tunable Diode Laser Absorption Spectroscopy (TDLAS) measurement of several water transitions that were interrogated during a hot-fire testing of the Space Launch Systems (SLS) sub-scale vehicle installed in LENS II. The temperature of the recirculating gas flow over the base plate was found to increase with altitude and is consistent with CFD results. It was also observed that the gas above the base plate has significant velocity along the optical path of the sensor at the higher altitudes. The line-by-line analysis of the H2O absorption features must include the effects of the Doppler shift phenomena particularly at high altitude. The TDLAS experimental measurements and the analysis procedure which incorporates the velocity dependent flow will be described.

  5. Electrochemical kinetics and X-ray absorption spectroscopy investigations of select chalcogenide electrocatalysts for oxygen reduction reaction applications

    International Nuclear Information System (INIS)

    Ziegelbauer, Joseph M.; Murthi, Vivek S.; O'Laoire, Cormac; Gulla, Andrea F.; Mukerjee, Sanjeev

    2008-01-01

    Transition metal-based chalcogenide electrocatalysts exhibit a promising level of performance for oxygen reduction reaction applications while offering significant economic benefits over the state of the art Pt/C systems. The most active materials are based on Ru x Se y clusters, but the toxicity of selenium will most likely limit their embrace by the marketplace. Sulfur-based analogues do not suffer from toxicity issues, but suffer from substantially less activity and stability than their selenium brethren. The structure/property relationships that result in these properties are not understood due to ambiguities regarding the specific morphologies of Ru x S y -based chalcogenides. To clarify these properties, an electrochemical kinetics study was interpreted in light of extensive X-ray diffraction, scanning electron microscopy, and in situ X-ray absorption spectroscopy evaluations. The performance characteristics of ternary M x Ru y S z /C (M = Mo, Rh, or Re) chalcogenide electrocatalysts synthesized by the now-standard low-temperature nonaqueous (NA) route are compared to commercially available (De Nora) Rh- and Ru-based systems. Interpretation of performance differences is made in regards to bulk and surface properties of these systems. In particular, the overall trends of the measured activation energies in respect to increasing overpotential and the gross energy values can be explained in regards to these differences

  6. Using waste heat of ship as energy source for an absorption refrigeration system

    International Nuclear Information System (INIS)

    Salmi, Waltteri; Vanttola, Juha; Elg, Mia; Kuosa, Maunu; Lahdelma, Risto

    2017-01-01

    Highlights: • A steady-state thermodynamic model is developed for absorption refrigeration in a ship. • Operation profile of B.Delta37 bulk carrier is used as an initial data. • Suitability of water-LiBr and ammonia-water working pairs were validated. • Coefficient of performance (COP) was studied in ISO and tropical conditions. • Estimated energy savings were 47 and 95 tons of fuel every year. - Abstract: This work presents a steady-state thermodynamic model for absorption refrigeration cycles with water-LiBr and ammonia-water working pairs for purpose of application on a ship. The coefficient of performance was studied with different generator and evaporator temperatures in ISO and tropical conditions. Absorption refrigeration systems were examined using exhaust gases, jacket water, and scavenge air as energy sources. Optimal generator temperatures for different refrigerant temperatures were found using different waste heat sources and for the absorption cycle itself. Critical temperature values (where the refrigeration power drops to zero) were defined. All of these values were used in order to evaluate the cooling power and energy production possibilities in a bulk carrier. The process data of exhaust gases and cooling water flows in two different climate conditions (ISO and tropical) and operation profiles of a B. Delta37 bulk carrier were used as initial data in the study. With the case ship data, a theoretical potential of saving of 70% of the electricity used in accommodation (AC use) compressor in ISO conditions and 61% in tropical conditions was recognized. Those estimates enable between 47 and 95 tons of annual fuel savings, respectively. Moreover, jacket water heat recovery with a water-LiBr system has the potential to provide 2.2–4.0 times more cooling power than required during sea-time operations in ISO conditions, depending on the main engine load.

  7. Experimental investigation on an ammonia-water-lithium bromide absorption refrigeration system without solution pump

    International Nuclear Information System (INIS)

    Wu Tiehui; Wu Yuyuan; Yu Zhiqiang; Zhao Haichen; Wu Honglin

    2011-01-01

    Highlights: → An absorption refrigeration system with ternary solution of NH 3 -H 2 O-LiBr was set up. → Performance of the NH 3 -H 2 O-LiBr system without solution pump was firstly tested. → Generator pressure in NH 3 -H 2 O-LiBr system was lower than the one in NH 3 -H 2 O system. → The COP of the NH 3 -H 2 O-LiBr system was 51.89% larger than the NH 3 -H 2 O binary system. → The optimum mass fraction of LiBr of about 23% led to the largest COP of 0.401. -- Abstract: Experimental researches were carried out on a novel ammonia-water-lithium bromide ternary solution absorption refrigeration and air-conditioning system without solution pump and distillation equipments. The experiments were conducted by using three kinds of NH 3 -H 2 O binary solution and 17 kinds of ternary solution with difference in mass fraction of NH 3 and LiBr. The experimental results showed that the vapor pressure of the generator in the system would be lower than that of the generator in an ammonia-water absorption system. In above two situations the same ammonia mass fraction and the same solution temperature were kept. The amplitude of vapor pressure decrease of the system generator would be larger with the increase of the mass fraction of LiBr. The maximum amplitude of decrease would be of 50%. With the increase of the mass fraction of LiBr, the coefficient of performance (COP) of the system would be increased initially, and then decreased later when the mass fraction of LiBr exceeded a certain value. This value was about 23% for the solution with ammonia mass fraction of 50% and 55%, and about 30% for the solution with ammonia mass fraction of 60%. Compared with the ammonia-water system, the COP of the ternary solution system with the same mass fraction of ammonia would increase up to 30%. With the ammonia mass fraction of 60% and LiBr mass fraction of 30% applied, the COP of the ternary solution system was increased up to 0.401. It was 51.89% higher than that when binary

  8. Observations of nickel, chromium, and zinc in QSO absorption-line systems

    International Nuclear Information System (INIS)

    Meyer, D.M.; Roth, K.C.

    1990-01-01

    New observations of Ni II, Cr II, and Zn II in several damped Ly-alpha QSO absorption-line systems at z about 2 are presented. Using the N(Zn II)/N(H I) ratio as a probe of the metallicity and N(Cr II)/N(Zn II) as a measure of the dust content, it is found that the heavy-element abundances in the z = 1.921 system toward the QSO 2206-199N are 20 percent solar and that the dust-to-gas ratio is 11 percent of the Galactic disk value. The observations of these species in the z = 2.309 system toward PHL 957 yield a more extreme metallicity (4 percent solar) and dust-to-gas ratio (3 percent Galactic). In addition, a depletion of Ni in the z = 2.039 absorber toward PKS 0458 - 020 and an absence of C I absorption in the z about 2 damped systems toward 1215 + 333 and 2359 - 022 are found which are consistent with a lack of dust. Among the four damped systems whose Ni, Cr, and Zn abundances have been examined quantitatively to date, all show convincing evidence of much lower metallicities and dust content than the Galactic disk. The implications of these results with regard to the interpretation of the high-redshift damped Ly-alpha systems as an evolving population of young galaxies are discussed. 41 refs

  9. Moisture absorption characteristics of the Orbiter thermal protection system and methods used to prevent water ingestion

    Science.gov (United States)

    Schomburg, C.; Dotts, R. L.; Tillian, D. J.

    1983-01-01

    The Space Shuttle Orbiter's silica tile Thermal Protection System (TPS) is beset by the moisture absorption problems inherently associated with low density, highly porous insulation systems. Attention is presently given to the comparative success of methods for the minimization and/or prevention of water ingestion by the TPS tiles, covering the development of water-repellent agents and their tile application techniques, flight test program results, and materials improvements. The use of external films for rewaterproofing of the TPS tiles after each mission have demonstrated marginal to unacceptable performance. By contrast, a tile interior waterproofing agent has shown promise.

  10. Second law comparison of single effect and double effect vapour absorption refrigeration systems

    International Nuclear Information System (INIS)

    Gomri, Rabah

    2009-01-01

    In this paper a comparative study between single effect and double effect absorption refrigeration systems with identical cold output is carried out. Simulation results were used to study the influence of the various operating parameters on the performance coefficient, the thermal loads of the components, exergetic efficiency (rational efficiency) and the total change in exergy of the two systems. It is concluded that the COP of double effect system is approximately twice the COP of single effect system but the exergetic efficiency of double effect system increase slightly compared to the exergetic efficiency of single effect system. It is found that for each condenser and evaporator temperature, there is an optimum generator temperature where the total change in exergy of the single effect and double effect absorption refrigeration systems is minimum. At this point the COP and exergetic efficiency of the systems become maximum. In this study and when the evaporation temperature is varied from 4 deg. C to 10 deg. C, condenser and absorber temperatures are varied from 33 deg. C to 39 deg. C and generator (HPG) temperature is varied from 60 deg. C to 190 deg. C the maximum COP values of the single effect refrigeration systems are in the range of 0.73-0.79 and for double effect refrigeration systems are in the range of 1.22-1.42. The maximum exergetic efficiency values of the single effect refrigeration systems are in the range of 12.5-23.2% and for double effect refrigeration systems are in the range of 14.3-25.1%.

  11. An In Silico Knockout Model for Gastrointestinal Absorption Using a Systems Pharmacology Approach - Development and Application for Ketones.

    Directory of Open Access Journals (Sweden)

    Vittal Shivva

    Full Text Available Gastrointestinal absorption and disposition of ketones is complex. Recent work describing the pharmacokinetics (PK of d-β-hydroxybutyrate (BHB following oral ingestion of a ketone monoester ((R-3-hydroxybutyl (R-3-hydroxybutyrate found multiple input sites, nonlinear disposition and feedback on endogenous production. In the current work, a human systems pharmacology model for gastrointestinal absorption and subsequent disposition of small molecules (monocarboxylic acids with molecular weight < 200 Da was developed with an application to a ketone monoester. The systems model was developed by collating the information from the literature and knowledge gained from empirical population modelling of the clinical data. In silico knockout variants of this systems model were used to explore the mechanism of gastrointestinal absorption of ketones. The knockouts included active absorption across different regions in the gut and also a passive diffusion knockout, giving 10 gut knockouts in total. Exploration of knockout variants has suggested that there are at least three distinct regions in the gut that contribute to absorption of ketones. Passive diffusion predominates in the proximal gut and active processes contribute to the absorption of ketones in the distal gut. Low doses are predominantly absorbed from the proximal gut by passive diffusion whereas high doses are absorbed across all sites in the gut. This work has provided mechanistic insight into the absorption process of ketones, in the form of unique in silico knockouts that have potential for application with other therapeutics. Future studies on absorption process of ketones are suggested to substantiate findings in this study.

  12. Intervening O vi Quasar Absorption Systems at Low Redshift: A Significant Baryon Reservoir.

    Science.gov (United States)

    Tripp; Savage; Jenkins

    2000-05-01

    Far-UV echelle spectroscopy of the radio-quiet QSO H1821+643 (zem=0.297), obtained with the Space Telescope Imaging Spectrograph (STIS) at approximately 7 km s-1 resolution, reveals four definite O vi absorption-line systems and one probable O vi absorber at 0.15quasar in redshift; these are likely intervening systems unrelated to the background QSO. In the case of the strong O vi system at zabs=0.22497, multiple components are detected in Si iii and O vi as well as H i Lyman series lines, and the differing component velocity centroids and b-values firmly establish that this is a multiphase absorption system. A weak O vi absorber is detected at zabs=0.22637, i.e., offset by approximately 340 km s-1 from the zabs=0.22497 system. Lyalpha absorption is detected at zabs=0.22613, but no Lyalpha absorption is significantly detected at 0.22637. Other weak O vi absorbers at zabs=0.24531 and 0.26659 and the probable O vi system at 0.21326 have widely diverse O vi/H i column density ratios with N(O vi)/N(H i) ranging from systems is Omegab(Ovi&parr0; greater, similar0.0008 h-175. With an assumed metallicity of 1/10 solar and a conservative assumption that the fraction of oxygen in the O vi ionization stage is 0.2, we obtain Omegab(Ovi&parr0; greater, similar0.004 h-175. This is comparable to the combined cosmological mass density of stars and cool gas in galaxies and X-ray-emitting gas in galaxy clusters at low redshift.

  13. Mathematical Model of a Lithium-Bromide/Water Absorption Refrigeration System Equipped with an Adiabatic Absorber

    Directory of Open Access Journals (Sweden)

    Salem M. Osta-Omar

    2016-11-01

    Full Text Available The objective of this paper is to develop a mathematical model for thermodynamic analysis of an absorption refrigeration system equipped with an adiabatic absorber using a lithium-bromide/water (LiBr/water pair as the working fluid. The working temperature of the generator, adiabatic absorber, condenser, evaporator, the cooling capacity of the system, and the ratio of the solution mass flow rate at the circulation pump to that at the solution pump are used as input data. The model evaluates the thermodynamic properties of all state points, the heat transfer in each component, the various mass flow rates, and the coefficient of performance (COP of the cycle. The results are used to investigate the effect of key parameters on the overall performance of the system. For instance, increasing the generator temperatures and decreasing the adiabatic absorber temperatures can increase the COP of the cycle. The results of this mathematical model can be used for designing and sizing new LiBr/water absorption refrigeration systems equipped with an adiabatic absorber or for optimizing existing aforementioned systems.

  14. Optimization of operation of energy supply systems with co-generation and absorption refrigeration

    Directory of Open Access Journals (Sweden)

    Stojiljković Mirko M.

    2012-01-01

    Full Text Available Co-generation systems, together with absorption refrigeration and thermal storage, can result in substantial benefits from the economic, energy and environmental point of view. Optimization of operation of such systems is important as a component of the entire optimization process in pre-construction phases, but also for short-term energy production planning and system control. This paper proposes an approach for operational optimization of energy supply systems with small or medium scale co-generation, additional boilers and heat pumps, absorption and compression refrigeration, thermal energy storage and interconnection to the electric utility grid. In this case, the objective is to minimize annual costs related to the plant operation. The optimization problem is defined as mixed integer nonlinear and solved combining modern stochastic techniques: genetic algorithms and simulated annealing with linear programming using the object oriented “ESO-MS” software solution for simulation and optimization of energy supply systems, developed as a part of this research. This approach is applied to optimize a hypothetical plant that might be used to supply a real residential settlement in Niš, Serbia. Results are compared to the ones obtained after transforming the problem to mixed 0-1 linear and applying the branch and bound method.

  15. Mechanism of enhanced oral absorption of morin by phospholipid complex based self-nanoemulsifying drug delivery system.

    Science.gov (United States)

    Zhang, Jinjie; Li, Jianbo; Ju, Yuan; Fu, Yao; Gong, Tao; Zhang, Zhirong

    2015-02-02

    Phospholipid complex (PLC) based self-nanoemulsifying drug delivery system (PLC-SNEDDS) has been developed for efficient delivery of drugs with poor solubility and low permeability. In the present study, a BCS class IV drug and a P-glycoprotein (P-gp) substrate, morin, was selected as the model drug to elucidate the oral absorption mechanism of PLC-SNEDDS. PLC-SNEDDS was superior to PLC in protecting morin from degradation by intestinal enzymes in vitro. In situ perfusion study showed increased intestinal permeability by PLC was duodenum-specific. In contrast, PLC-SNEDDS increased morin permeability in all intestinal segments and induced a change in the main absorption site of morin from colon to ileum. Moreover, ileum conducted the lymphatic transport of PLC-SNEDDS, which was proven by microscopic intestinal visualization of Nile red labeled PLC-SNEDDS and lymph fluids in vivo. Low cytotoxicity and increased Caco-2 cell uptake suggested a safe and efficient delivery of PLC-SNEDDS. The increased membrane fluidity and disrupted actin filaments were closely associated with the increased cell uptake of PLC-SNEDDS. PLC-SNEDDS could be internalized into enterocytes as an intact form in a cholesterol-dependent manner via clathrin-mediated endocytosis and macropinocytosis. The enhanced oral absorption of morin was attributed to the P-gp inhibition by Cremophor RH and the intact internalization of M-PLC-SNEDDS into Caco-2 cells bypassing P-gp recognition. Our findings thus provide new insights into the development of novel nanoemulsions for poorly absorbed drugs.

  16. A CCD-based system for the detection of DNA in electrophoresis gels by UV absorption

    International Nuclear Information System (INIS)

    Mahon, A.R.; MacDonald, J.H.; Mainwood, A.; Ott, R.J.

    1999-01-01

    A method and apparatus for the detection and quantification of large fragments of unlabelled nucleic acids in agarose gels is presented. The technique is based on ultraviolet (UV) absorption by nucleotides. A deuterium source illuminates individual sample lanes of an electrophoresis gel via an array of optical fibres. As DNA bands pass through the illuminated region of the gel the amount of UV light transmitted is reduced because of absorption by the DNA. During electrophoresis the regions of DNA are detected on-line using a UV-sensitive charge coupled device (CCD). As the absorption coefficient is proportional to the mass of DNA the technique is inherently quantitative. The mass of DNA in a region of the gel is approximately proportional to the integrated signal in the corresponding section of the CCD image. This system currently has a detection limit of less than 1.25 ng compared with 2-10 ng for the most popular conventional technique, ethidium bromide (EtBr) staining. In addition the DNA sample remains in its native state. The removal of the carcinogenic dye from the detection procedure greatly reduces associated biological hazards. (author)

  17. Experimental investigation on photothermal properties of nanofluids for direct absorption solar thermal energy systems

    International Nuclear Information System (INIS)

    He, Qinbo; Wang, Shuangfeng; Zeng, Shequan; Zheng, Zhaozhi

    2013-01-01

    Highlights: • The factors affecting the transmittance of Cu–H 2 O nanofluids were studied with UV–Vis–NIR spectrophotometer. • The optical properties of Cu–H 2 O nanofluids were studied through the theoretical model. • The Cu–H 2 O nanofluids can enhance the absorption ability for solar energy. - Abstract: In this article, Cu–H 2 O nanofluids were prepared through two-step method. The transmittance of nanofluids over solar spectrum (250–2500 nm) was measured by the UV–Vis–NIR spectrophotometer based on integrating sphere principle. The factors influencing transmittance of nanofluids, such as particle size, mass fraction and optical path were investigated. The extinction coefficients measured experimentally were compared with the theoretical calculation value. Meanwhile, the photothermal properties of nanofluids were also investigated. The experimental results show that the transmittance of Cu–H 2 O nanofluids is much less than that of deionized water, and decreases with increasing nanoparticle size, mass fraction and optical depth. The highest temperature of Cu–H 2 O nanofluids (0.1 wt.%) can increased up to 25.3% compared with deionized water. The good absorption ability of Cu–H 2 O nanofluids for solar energy indicates that it is suitable for direct absorption solar thermal energy systems

  18. Enhancement of absorption and hepatoprotective potential through soya-phosphatidylcholine-andrographolide vesicular system.

    Science.gov (United States)

    Jain, Pushpendra Kumar; Khurana, Navneet; Pounikar, Yogesh; Gajbhiye, Asmita; Kharya, Murli Dhar

    2013-06-01

    Andrographis paniculata is a medicinal herb used extensively for various ailments and contains therapeutically active phytoconstituent, andrographolide (AN). Although hepatoprotective activity of AN is established, but their bioavailability is restricted due to its rapid clearance. The aim of this study, therefore, was to formulate AN herbosomes (ANH) through complexation with naturally occurring soya-phosphatidylcholine (SPC), in order to enhance absorption. Prepared andrographolide-soy phosphatidylcholine (AN-SPC) complex prepared was subjected for characterisation of complex and formation of vesicular system known as ANH using rotary evaporation techniques. This complex was subjected to in vitro study using everted small intestine sac technique which showed significantly increased absorption of AN from the ANH as compared to the plain AN. The hepatoprotective potential of ANH and plain AN was evaluated using carbon tetrachloride inducing hepatotoxicity rat model and compared, in which ANH equivalent to 50 mg/kg of plain AN significantly restore serum glutamate oxalacetate transaminase (112.4 ± 9.67 for AN whereas 90.2 ± 4.23 for ANH) and serum glutamate pyruvate transaminase (109.3 ± 7.89 for AN whereas 90.6 ± 4.34 for ANH) level as compared to control group. The ANH showed significantly better absorption than plain AN and this effect of ANH was also comparable to the standard drug (Silymarin). The findings of present study reveal that ANH has better bioavailability as shown by in vitro absorption study and hence improved hepatoprotection as compared to plain AN at equivalent dose.

  19. UV absorption cross-sections of selected sulfur-containing compounds at temperatures up to 500°C

    DEFF Research Database (Denmark)

    Grosch, Helge; Fateev, Alexander; Clausen, Sønnik

    2015-01-01

    The temperature dependence of the ultraviolet absorption cross-sections of three different sulfur containing compounds, hydrogen sulfide (H2S), carbon disulfide (CS2) and carbonyl sulfide (OCS), are presented between 200nm and 360nm at a resolution of 0.018nm. The absorption cross-sections for each...... compound are initially compared with those available in the literature, followed by the discussion of the measurements and their spectral features at three temperatures up to 500°C/773K. Uncertainties in the measured absorption cross-sections are also addressed....

  20. Thermo- economical consideration of Regenerative organic Rankine cycle coupling with the absorption chiller systems incorporated in the trigeneration system

    International Nuclear Information System (INIS)

    Anvari, Simin; Taghavifar, Hadi; Parvishi, Alireza

    2017-01-01

    Highlights: • A new trigeneration cycle was studied from a new viewpoint of exergoeconomic and thermodynamic. • Organic Rankine and refrigeration cycles are used for recovery waste heat of cogeneration system. • Application of trigeneration cycles is advantageous in economical and thermodynamic aspects. - Abstract: In this paper, a combined cooling, heating and power cycle is proposed consisting of three sections of gas turbine and heat recovery steam generator cycle, Regenerative organic Rankine cycle, and absorption refrigeration cycle. This trigeneration cycle is subjected to a thorough thermodynamic and exergoeconomic analysis. The principal goal followed in the investigation is to address the thermodynamic and exergoeconomic of a trigeneration cycle from a new prospective such that the economic and thermodynamic viability of incorporating Regenerative organic Rankine cycle, and absorption refrigeration cycle to the gas turbine and heat recovery steam generator cycle is being investigated. Thus, the cost-effectiveness of the introduced method can be studied and further examined. The results indicate that adding Regenerative organic Rankine cycle to gas turbine and heat recovery steam generator cycle leads to 2.5% increase and the addition of absorption refrigeration cycle to the gas turbine and heat recovery steam generator/ Regenerative Organic Rankine cycle would cause 0.75% increase in the exergetic efficiency of the entire cycle. Furthermore, from total investment cost of the trigeneration cycle, only 5.5% and 0.45% results from Regenerative organic Rankine cycle and absorption refrigeration cycles, respectively.

  1. Analysis of a gas absorption system with soluble carrier gas and volatile solvent

    International Nuclear Information System (INIS)

    Kanak, B.E.

    1980-01-01

    The effects of column diameter, carrier gas coabsorption, and solvent vaporization on the performance of a packed gas absorption column are examined. The system investigated employs dichlorodifluoromethane as a solvent to remove krypton from a nitrogen stream and is characterized by substantial nitrogen coabsorption. Three columns with diameters of 2, 3, and 4 inches were constructed and packed with 34.5 inches of Goodloe packing. In addition to the more conventional data, the experimental evaluation of these columns included the use of a radioisotope and a gamma scanning technique which provided direct measurement of the columns' molar krypton profiles. A multicomponent gas absorption model was developed, based on the two-film mass transfer theory, that allows the fluxes of all species to interact. Verification of this model was achieved through comparison of the calculated results with experimental data. With the feed gas flow rate between 6 and 36 lb moles/hr-ft 2 and the solvent feed rate between 40 and 400 lb moles/hr-ft 2 , column diameter was found to have no significant impact on the mass transfer efficiency of this system when carried out in columns with diameters of 2 inches or greater. The absorption of krypton was found to be enhanced and inhibited, respectively, by carrier gas coabsorption and solvent vaporization. An injector system to add gaseous solvent to the feed gas stream prior to its introduction into the packed bed was proposed to eliminate the detrimental effects of solvent vaporization.Using this injector to supersaturate the feed gas stream with solvent enhanced absorber performance in the same manner as carrier gas coabsorption

  2. A solar absorption refrigeration system operating with the mixture ammonia-lithium nitrate

    Energy Technology Data Exchange (ETDEWEB)

    Rivera, W.; Martinez, F.; Garcia-Valladares, O. [Centro de Investigacion en Energia de la Univ. Nacional Autonoma de Mexico, Mor (Mexico); Rivera, C.O. [Univ. Veracruzana, Campus Coatzacoalcos (Mexico)

    2007-07-01

    An intermittent solar absorption refrigeration system for ice production operating with the ammonia-lithium nitrate mixture has been developed in the Centro de Investigacion en Energia of the Universidad Nacional Autonoma de Mexico. The system consists basically of a compound parabolic concentrator (CPC), a generator-absorber, a condenser, a condensate tank, an expansion valve and an evaporator. The system was evaluated in sunny days with insolations above 20 MJ/m{sup 2}-day at different condenser temperatures. The generator temperatures varied from 108 to 121 C and the evaporator temperatures inside the camera from -8 to 0 C. The coefficients of performance (COP) varied from 0.13 to 0.26 depending of the operating temperatures of the system and the solar irradiation. (orig.)

  3. The standard calibration instrument automation system for the atomic absorption spectrophotometer. Part 3: Program documentation

    Science.gov (United States)

    Ryan, D. P.; Roth, G. S.

    1982-04-01

    Complete documentation of the 15 programs and 11 data files of the EPA Atomic Absorption Instrument Automation System is presented. The system incorporates the following major features: (1) multipoint calibration using first, second, or third degree regression or linear interpolation, (2) timely quality control assessments for spiked samples, duplicates, laboratory control standards, reagent blanks, and instrument check standards, (3) reagent blank subtraction, and (4) plotting of calibration curves and raw data peaks. The programs of this system are written in Data General Extended BASIC, Revision 4.3, as enhanced for multi-user, real-time data acquisition. They run in a Data General Nova 840 minicomputer under the operating system RDOS, Revision 6.2. There is a functional description, a symbol definitions table, a functional flowchart, a program listing, and a symbol cross reference table for each program. The structure of every data file is also detailed.

  4. Investigation of periodically driven systems by x-ray absorption spectroscopy using asynchronous data collection mode

    Science.gov (United States)

    Singh, H.; Donetsky, D.; Liu, J.; Attenkofer, K.; Cheng, B.; Trelewicz, J. R.; Lubomirsky, I.; Stavitski, E.; Frenkel, A. I.

    2018-04-01

    We report the development, testing, and demonstration of a setup for modulation excitation spectroscopy experiments at the Inner Shell Spectroscopy beamline of National Synchrotron Light Source - II. A computer algorithm and dedicated software were developed for asynchronous data processing and analysis. We demonstrate the reconstruction of X-ray absorption spectra for different time points within the modulation pulse using a model system. This setup and the software are intended for a broad range of functional materials which exhibit structural and/or electronic responses to the external stimulation, such as catalysts, energy and battery materials, and electromechanical devices.

  5. Implications of a primordial origin for the dispersion in D/H in quasar absorption systems.

    Science.gov (United States)

    Copi, C J; Olive, K A; Schramm, D N

    1998-03-17

    We explore the difficulties with a primordial origin of variations of D/H in quasar absorption systems. In particular we examine options such as a very large-scale inhomogeneity in the baryon content of the universe. We show that very large-scale (much larger than 1 Mpc) isocurvature perturbations are excluded by current cosmic microwave background observations. Smaller-scale ad hoc perturbations (approximately 1 Mpc) still may lead to a large dispersion in primordial abundances but are subject to other constraints.

  6. Absorption spectra of thin films of triple compounds in the system RbIPbI2

    International Nuclear Information System (INIS)

    Yunakova, O.N.; Miloslavskij, V.K.; Ksenofontova, E.V.; Kovalenko, E.N.

    2012-01-01

    A formation of compounds RbPbI 3 and Rb 4 PbI 6 in the system RbI-PbI 2 is revealed and their absorption spectra are investigated in an energy interval 2-6 eV and a temperatures range 90-500 K. It is established that the low-frequency exciton excitations are localized in PbI 6 4- structural elements of the crystal lattice, they are classified as excitons of intermediate coupling and are of a three-dimensional character in RbPbI 3 and a quasi-two-dimensional one in Rb 4 PbI 6 .

  7. Exergy analysis of single effect absorption refrigeration systems: The heat exchange aspect

    International Nuclear Information System (INIS)

    Joybari, Mahmood Mastani; Haghighat, Fariborz

    2016-01-01

    Highlights: • Exergy analysis of LiBr/H 2 O absorption systems with identical COP was carried out. • Exergy destruction rank: absorber followed by generator, condenser and evaporator. • Lower heat source and chilled water inlet temperature reduced exergy destruction. • Higher cooling water inlet temperature reduced exergy destruction. • Lower HTF mass flow rate increased exergy efficiency even for fixed system COP. - Abstract: The main limitation of conventional energy analysis for the thermal performance of energy systems is that this approach does not consider the quality of energy. On the other hand, exergy analysis not only provides information about the systems performance, but also it can specify the locations and magnitudes of losses. A number of studies investigated the effect of parameters such as the component temperature, and heat transfer fluid (HTF) temperature and mass flow rate on the exergetic performance of the same absorption refrigeration system; thus, reported different coefficient of performance (COP) values. However, in this study, the system COP was considered to remain constant during the investigation. This means comparing systems with different heat exchanger designs (based on HTF mass flow rate and temperature) having the same COP value. The effect of HTF mass flow rate and inlet temperature of the cooling water, chilled water and heat source on the outlet specific exergy and exergy destruction rate of each component was investigated. It was found that the lower HTF mass flow rate decreased exergy destruction of the corresponding component. Moreover, the lower temperature of heat source and chilled water inlet increased the system exergetic efficiency. That was also the case for the higher cooling water inlet temperature. Based on the analysis, since the absorber and condenser accounted for a large portion of the total exergy destruction, cooling tower modification with lower cooling water mass flow rate is recommended

  8. Simulation of solar lithium bromide-water absorption cooling system with parabolic trough collector

    International Nuclear Information System (INIS)

    Mazloumi, M.; Naghashzadegan, M.; Javaherdeh, K.

    2008-01-01

    Ahwaz is one of the sweltering cities in Iran where an enormous amount of energy is being consumed to cool residential places in a year. The aim of this research is to simulate a solar single effect lithium bromide-water absorption cooling system in Ahwaz. The solar energy is absorbed by a horizontal N-S parabolic trough collector and stored in an insulated thermal storage tank. The system has been designed to supply the cooling load of a typical house where the cooling load peak is about 17.5 kW (5 tons of refrigeration), which occurs in July. A thermodynamic model has been used to simulate the absorption cycle. The working fluid is water, which is pumped directly to the collector. The results showed that the collector mass flow rate has a negligible effect on the minimum required collector area, but it has a significant effect on the optimum capacity of the storage tank. The minimum required collector area was about 57.6 m 2 , which could supply the cooling loads for the sunshine hours of the design day for July. The operation of the system has also been considered after sunset by saving solar energy

  9. Supplier Selection Using Fuzzy Inference System

    Directory of Open Access Journals (Sweden)

    hamidreza kadhodazadeh

    2014-01-01

    Full Text Available Suppliers are one of the most vital parts of supply chain whose operation has significant indirect effect on customer satisfaction. Since customer's expectations from organization are different, organizations should consider different standards, respectively. There are many researches in this field using different standards and methods in recent years. The purpose of this study is to propose an approach for choosing a supplier in a food manufacturing company considering cost, quality, service, type of relationship and structure standards of the supplier organization. To evaluate supplier according to the above standards, the fuzzy inference system has been used. Input data of this system includes supplier's score in any standard that is achieved by AHP approach and the output is final score of each supplier. Finally, a supplier has been selected that although is not the best in price and quality, has achieved good score in all of the standards.

  10. The Research on Programmable Control System of Lithium-Bromide Absorption Refrigerating Air Conditioner Based on the Network

    Directory of Open Access Journals (Sweden)

    Sun Lunan

    2016-01-01

    Full Text Available This article regard the solar lithium-bromide absorption refrigerating air conditioning system as the research object, and it was conducting adequate research of the working principle of lithium bromide absorption refrigerating machine, also it was analyzing the requirements of control system about solar energy air conditioning. Then the solar energy air conditioning control system was designed based on PLC, this system was given priority to field bus control system, and the remote monitoring is complementary, which was combining the network remote monitoring technology. So that it realized the automatic control and intelligent control of new lithium bromide absorption refrigerating air conditioning system with solar energy, also, it ensured the control system can automatically detect and adjust when the external conditions was random changing, to make air conditioning work effectively and steadily, ultimately ,it has great research significance to research the air conditioning control system with solar energy.

  11. Energy and parametric analysis of solar absorption cooling systems in various Moroccan climates

    Directory of Open Access Journals (Sweden)

    Y. Agrouaz

    2017-03-01

    Full Text Available The aim of this work is to investigate the energetic performance of a solar cooling system using absorption technology under Moroccan climate. The solar fraction and the coefficient of performance of the solar cooling system were evaluated for various climatic conditions. It is found that the system operating in Errachidia shows the best average annual solar fraction (of 30% and COP (of 0.33 owing to the high solar capabilities of this region. Solar fraction values in other regions varied between 19% and 23%. Moreover, the coefficient of performance values shows in the same regions a significant variation from 0.12 to 0.33 all over the year. A detailed parametric study was as well carried out to evidence the effect of the operating and design parameters on the solar air conditioner performance.

  12. Open absorption system for cooling and air conditioning using membrane contactors. 2006 annual report

    Energy Technology Data Exchange (ETDEWEB)

    Conde-Petit, M. [M. Conde Engineering, Zuerich (Switzerland); Weber, R. [Materials Science and Technology (EMPA), Abteilung Bautechnologien, Duebendorf (Switzerland)

    2006-11-15

    This illustrated annual report for 2006 for the Swiss Federal Office of Energy (SFOE) reports on work being done on the development of an open absorption system for cooling and air-conditioning. The report reviews the construction of a first prototype and the manufacture of its components. The conceptual design of this new type of air handling unit (AHU), operating with a liquid desiccant, is discussed. The AHU is to be autonomous and the system will not require additional mechanical refrigeration. It is to be thermally driven at temperatures below 80 {sup o}C. Waste heat sources, solar collectors, district heating plants and co-generation systems are targeted as providers of thermal energy at this temperature level. Work carried out is reported on, including that on two-stream membrane contactors.

  13. Thermodynamic analysis of a combined gas turbine, ORC cycle and absorption refrigeration for a CCHP system

    International Nuclear Information System (INIS)

    Mohammadi, Amin; Kasaeian, Alibakhsh; Pourfayaz, Fathollah; Ahmadi, Mohammad Hossein

    2017-01-01

    Highlights: • Thermodynamic analysis of a hybrid CCHP system. • Sensitivity analysis is performed on the most important parameters of the system. • Pressure ratio and gas turbine inlet temperature are the most effective parameters. - Abstract: Hybrid power systems are gained more attention due to their better performance and higher efficiency. Widespread use of these systems improves environmental situation as they reduce the amount of fossil fuel consumption. In this paper a hybrid system composed of a gas turbine, an ORC cycle and an absorption refrigeration cycle is proposed as a combined cooling, heating and power system for residential usage. Thermodynamic analysis is applied on the system. Also a parametric analysis is carried out to investigate the effect of different parameters on the system performance and output cooling, heating and power. The results show that under design conditions, the proposed plant can produce 30 kW power, 8 kW cooling and almost 7.2 ton hot water with an efficiency of 67.6%. Moreover, parametric analysis shows that pressure ratio and gas turbine inlet temperature are the most important and influential parameters. After these two, ORC turbine inlet temperature is the most effective parameter as it can change both net output power and energy efficiency of the system.

  14. Application of vacuum membrane distillation to lithium bromide absorption refrigeration system

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zanshe; Feng, Shiyu; Li, Yun [School of Energy and Power Engineering, Xi' an Jiaotong University, Xi' an 710049 (China); Gu, Zhaolin [School of Human Settlement and Civil Engineering, Xi' an Jiaotong University, Xi' an 710049 (China)

    2009-11-15

    Conventional generator in lithium bromide absorption refrigeration system is too bulky and heavy to be fitted into small scale device, and the temperature of the driving heater in the generator seems much higher than low grade energy such as regenerative energy or waste heat energy. In this paper, desorption of aqueous lithium bromide solution by vacuum membrane distillation process was presented. Hollow fiber membrane module made by polyvinylidene fluoride was used as desorption device of aqueous lithium bromide solution. Influencing factors of feed flux, feed temperature in lumen side and vacuum pressure in shell side were tested and analyzed with orthogonal test. The results showed that permeation flux of water vapor increased with the feed temperature increasing and the feed flux increasing in lumen side, and the permeation flux also went up along with absolute pressure drop in shell side. Feasibility and potential application analysis shows that the temperature of the driving heat was low and the volume and weight of the desorption device was light. In this study, vacuum membrane distillation to the lithium bromide absorption refrigeration system has proved to be an efficient and cheap desorption mode. (author)

  15. A Lack of Systemic Absorption Following the Repeated Application of Topical Quetiapine in Healthy Adults.

    Science.gov (United States)

    Kayhart, Bryce; Lapid, Maria I; Nelson, Sarah; Cunningham, Julie L; Thompson, Virginia H; Leung, Jonathan G

    2018-01-01

    In the absence of suitable oral or intravenous access for medication administration and when the intramuscular medications are undesirable, alternative routes for drug delivery may be considered. Antipsychotics administered via an inhaled, intranasal, rectal, or topical route have been described in the literature. Topically administered antipsychotics have been previously reported to produce negligible systemic absorption despite being used in clinical practice for nausea and behavioral symptoms associated with dementia. Additionally, the American Academy of Hospice and Palliative Medicine recommends against the use of topical medications that lack supporting literature. Three studies have assessed the systemic absorption of different antipsychotics after administration of only a single, topically applied dose. To evaluate whether the repeated administration of a topically applied antipsychotic may result in detectable serum levels in an accumulating fashion, a pharmacokinetic study was conducted. Five healthy, adult participants consented to receive extemporaneously prepared topical quetiapine in Lipoderm every 4 hours for a total of 5 doses. Blood samples were drawn at baseline and hours 2, 4, 8, 12, 16, and 24, and serum quetiapine concentrations were measured using high-performance liquid chromatography. Quetiapine was undetectable in every sample from 3 participants. Two participants had minimally detectable serum quetiapine levels no sooner than hour 12 of the study period. Extemporaneously prepared quetiapine in Lipoderm resulted in nonexistent or minimal serum level following repeated topical administration. The use of topically applied quetiapine should still be questioned.

  16. Continuous optical measurement system of hemolysis during a photosensitization reaction using absorption spectrum

    Science.gov (United States)

    Hamada, R.; Ogawa, E.; Arai, T.

    2018-02-01

    To investigate hemolysis phenomena during a photosensitization reaction with the reaction condition continuously and simultaneously for a safety assessment of hemolysis side effect, we constructed an optical system to measure blood sample absorption spectrum during the reaction. Hemolysis degree might be under estimated in general evaluation methods because there is a constant oxygen pressure assumption in spite of oxygen depression take place. By investigating hemoglobin oxidation and oxygen desorption dynamics obtained from the contribution of the visible absorption spectrum and multiple regression analysis, both the hemolysis phenomena and its oxygen environment might be obtained with time. A 664 nm wavelength laser beam for the reaction excitation and 475-650 nm light beam for measuring the absorbance spectrum were arranged perpendicularly crossing. A quartz glass cuvette with 1×10 mm in dimensions for the spectrum measurement was located at this crossing point. A red blood cells suspension medium was arranged with low hematocrit containing 30 μg/ml talaporfin sodium. This medium was irradiated up to 40 J/cm2 . The met-hemoglobin, oxygenatedhemoglobin, and deoxygenated-hemoglobin concentrations were calculated by a multiple regression analysis from the measured spectra. We confirmed the met-hemoglobin concentration increased and oxygen saturation decreased with the irradiation time, which seems to indicate the hemolysis progression and oxygen consumption, respectively. By using our measuring system, the hemolysis progression seems to be obtained with oxygen environment information.

  17. Experimental investigation of integrated refrigeration system (IRS) with gas engine, compression chiller and absorption chiller

    International Nuclear Information System (INIS)

    Sun, Z.G.

    2008-01-01

    An integrated refrigeration system (IRS) with a gas engine, a vapor-compression chiller and an absorption chiller is set up and tested. The vapor-compression refrigeration cycle is operated directly by the gas engine. The waste heat from the gas engine operates the absorption refrigeration cycle, which provides additional cooling. The performance of the IRS is described. The cooling capacity of the IRS is about 596 kW, and primary energy ratio (PER) reaches 1.84 at air-conditioning rated conditions. The refrigerating capacity of the prototype increased and PER of prototype decreased with the increase of the gas engine speed. The gas engine speed was preferably regulated at part load condition in order to operate the prototype at high-energy efficiency. The refrigerating capacity and PER of the prototype increased with the increase of the outlet temperature of chilled water or the decrease of the inlet temperature of cooling water. The integrated refrigeration chiller in this work saves running costs as compared to the conventional refrigeration system by using the waste heat

  18. Corneal Absorption of a New Riboflavin-Nanostructured System for Transepithelial Collagen Cross-Linking

    Science.gov (United States)

    Bottos, Katia M.; Oliveira, Anselmo G.; Bersanetti, Patrícia A.; Nogueira, Regina F.; Lima-Filho, Acácio A. S.; Cardillo, José A.; Schor, Paulo; Chamon, Wallace

    2013-01-01

    Corneal collagen cross-linking (CXL) has been described as a promising therapy for keratoconus. According to standard CXL protocol, epithelium should be debrided before treatment to allow penetration of riboflavin into the corneal stroma. However, removal of the epithelium can increase procedure risks. In this study we aim to evaluate stromal penetration of a biocompatible riboflavin-based nanoemulsion system (riboflavin-5-phosphate and riboflavin-base) in rabbit corneas with intact epithelium. Two riboflavin nanoemulsions were developed. Transmittance and absorption coefficient were measured on corneas with intact epithelia after 30, 60, 120, 180, and 240 minutes following exposure to either the nanoemulsions or standard 0.1% or 1% riboflavin-dextran solutions. For the nanoemulsions, the epithelium was removed after measurements to assure that the riboflavin had passed through the hydrophobic epithelium and retained within the stroma. Results were compared to de-epithelialized corneas exposed to 0.1% riboflavin solution and to the same riboflavin nanoemulsions for 30 minutes (standard protocol). Mean transmittance and absorption measured in epithelialized corneas receiving the standard 0.1% riboflavin solution did not reach the levels found on the debrided corneas using the standard technique. Neither increasing the time of exposure nor the concentration of the riboflavin solution from 0.1% to 1% improved riboflavin penetration through the epithelium. When using riboflavin-5-phosphate nanoemulsion for 240 minutes, we found no difference between the mean absorption coefficients to the standard cross-linking protocol (p = 0.54). Riboflavin nanoemulsion was able to penetrate the corneal epithelium, achieving, after 240 minutes, greater stromal concentration when compared to debrided corneas with the standard protocol (p = 0.002). The riboflavin-5-phosphate nanoemulsion diffused better into the stroma than the riboflavin-base nanoemulsion. PMID:23785497

  19. Determination of selected metals in urban runoff and related estuarine sediments by neutron activation and atomic absorption

    International Nuclear Information System (INIS)

    Christensen, E.R.; Guinn, V.P.; Scherfig, J.

    1977-01-01

    Pollution sources for Newport Bay, California are of a nonpoint nature. To assess the heavy metals loading of the runoff into the Bay, 18 water samples, taken during dry and rainy periods, have been analyzed for Mn, Cu, Zn, and Pb, using atomic absorption spectrometry (AAS). In addition, 7 sediment cores from the Upper Bay and 5 sediment grab samples from the Lower Bay were analyzed for Cr, Mn, Fe, Co, Cu, Zn, and Pb. Instrumental neutron activation analysis (INAA) was used for Cr, Fe, and Co, whereas Mn, Cu, and Pb were determined by AAS. Zinc was determined by both of these techniques. Three major streams pass into Newport Bay carrying: (1) agricultural and to some extent urban and residential runoff (70-90%), (2) urban runoff (10-30%), and (3) residential runoff (<5%). The levels of Zn and Pb are much higher under storm conditions, e.g., 338 μg/l Zn and 425 μg/l Pb, than during dry weather, where typical concentrations are 20 μg/l Zn and 9 μg/l Pb. For Cu there is a moderate increase from about 10 μg/l in dry weather to a maximum of 54 μg/l under storm conditions. Soil erosion appears to be responsible for high Mn values (max. 1230 μg/l) in agricultural storm runoff. The cleansing action of a storm is evidenced by high concentrations in the beginning, and much lower levels towards the end of the storm.Vertical profiles of heavy metals in sediment cores indicate that Zn and Pb are the only metals of those investigated that show clearly increased levels in the uppermost layers. Typical enrichment ratios are 2.0 for Zn and 5.5 for Pb. Maximum concentrations of Zn and Pb in sediments from the Upper Bay were 300 ppm and 132 ppm, respectively. The highest Pb value was found close to the mouth of the urban drainage channel. Dating of selected cores was carried out by the Pb-210 method. Mass injection rates into Upper Newport Bay for Zn and Pb of anthropogenic origin were estimated to be 6.0 and 6.5 tons/yr, respectively

  20. Selection of fluids for tritium pumping systems

    International Nuclear Information System (INIS)

    Chastagner, P.

    1984-02-01

    The degradation characteristics of three types of vacuum pump fluids, polyphenyl ethers, perfluoropolyethers and hydrocarbon oils were reviewed. Fluid selection proved to be a critical factor in the long-term performance of tritium pumping systems and subsequent tritium recovery operations. Thermal degradation and tritium radiolysis of pump fluids produce contaminants which can damage equipment and interfere with tritium recovery operations. General characteristics of these fluids are as follows: polyphenyl ether has outstanding radiation resistance, is very stable under normal diffusion pump conditions, but breaks down in the presence of oxygen at anticipated operating temperatures. Perfluoropolyether fluids are very stable and do not react chemically with most gases. Thermal and mechanical degradation products are inert, but the radiolysis products are very corrosive. Most of the degradation products of hydrogen oils are volatile and the principal radiolysis product is methane. Our studies show that polyphenyl ethers and hydrocarbon oils are the preferred fluids for use in tritium pumping systems. No corrosive materials are formed and most of the degradation products can be removed with suitable filter systems

  1. Process for Selecting System Level Assessments for Human System Technologies

    Science.gov (United States)

    Watts, James; Park, John

    2006-01-01

    The integration of many life support systems necessary to construct a stable habitat is difficult. The correct identification of the appropriate technologies and corresponding interfaces is an exhaustive process. Once technologies are selected secondary issues such as mechanical and electrical interfaces must be addressed. The required analytical and testing work must be approached in a piecewise fashion to achieve timely results. A repeatable process has been developed to identify and prioritize system level assessments and testing needs. This Assessment Selection Process has been defined to assess cross cutting integration issues on topics at the system or component levels. Assessments are used to identify risks, encourage future actions to mitigate risks, or spur further studies.

  2. Identification of MgII Absorption Line Systems from SDSS Quasar ...

    Indian Academy of Sciences (India)

    Motivation. The quasar absorption lines are crucial to our understanding of the Universe since the absorption lines provide a wealth of information on the gaseous Universe from high redshift to present day. The absorption lines can also allow us to probe the metallicity and ionization state of the gas (Wild et al. 2008).

  3. Inhibition of two-photon absorption in a three-level system with a pair of bichromatic fields

    International Nuclear Information System (INIS)

    Zou Jinhua; Hu Xiangming; Cheng Guangling; Li Xing; Du Dan

    2005-01-01

    We study two-photon absorption in a three-level ladder atomic system driven by a pair of bichromatic fields of equal frequency differences. The high-frequency component of one bichromatic field and the low-frequency component of the other are on two-photon resonance. The transition probability is calculated by employing the method of harmonic expansion and matrix inversion. Unexpectedly, when the sums of the phases of the different pairs of field components on the two-photon resonance are equal to each other, two-photon absorption is dramatically suppressed and the atomic system becomes transparent against two-photon absorption. Physically, due to dynamical Stark splitting, the two-photon transitions induced by the different pairs of field components experience different dressed states with phase difference of π. As a result, destructive interference occurs between the two pathways and leads to the inhibition of two-photon absorption

  4. Three-dimensional atom localization via probe absorption in a cascade four-level atomic system

    Directory of Open Access Journals (Sweden)

    Zeng Wei

    2018-03-01

    Full Text Available For an atomic system with cascade four-level type, a useful scheme about three-dimensional (3D atom localization is proposed. In our scheme the atomic system is coherently controlled by using a radio-frequency field to couple with two-folded levels under the condition of the existence of probe absorption. Our results show that detecting precision of 3D atom localization may be obviously improved by properly adjusting the frequency detuning and strength of the radio-frequency driving field. So our scheme could be helpful to realize 3D atom localization with high-efficiency and high-precision . In the field of laser cooling or the atom nano-lithography, our studies provide potential applications.

  5. Three-dimensional atom localization via probe absorption in a cascade four-level atomic system

    Science.gov (United States)

    Zeng, Wei; Deng, Li; Chen, Aixi

    2018-03-01

    For an atomic system with cascade four-level type, a useful scheme about three-dimensional (3D) atom localization is proposed. In our scheme the atomic system is coherently controlled by using a radio-frequency field to couple with two-folded levels under the condition of the existence of probe absorption. Our results show that detecting precision of 3D atom localization may be obviously improved by properly adjusting the frequency detuning and strength of the radio-frequency driving field. So our scheme could be helpful to realize 3D atom localization with high-efficiency and high-precision . In the field of laser cooling or the atom nano-lithography, our studies provide potential applications.

  6. Energy and Exergy Based Optimization of Licl-Water Absorption Cooling System

    Directory of Open Access Journals (Sweden)

    Bhargav Pandya

    2017-06-01

    Full Text Available This study presents thermodynamic analysis and optimization of single effect LiCl-H2O absorption cooling system. Thermodynamic models are employed in engineering equation solver to compute the optimum performance parameters. In this study, cut off temperature to operate system has been obtained at various operating temperatures. Analysis depicts that on 3.59 % rise in evaporator temperature, the required cut-off temperature decreased by 12.51%. By realistic comparison between thermodynamic first and second law analysis, optimum generator temperature relative to energy and exergy based prospective has been evaluated. It is found that optimum generator temperature is strong function of evaporator and condenser temperature. Thus, it is feasible to find out optimum generator temperature for various combinations of evaporator and condenser temperatures. Contour plots of optimum generator temperature for several combinations of condenser and absorber temperatures have been also depicted.

  7. Vibration energy absorption in the whole-body system of a tractor operator.

    Science.gov (United States)

    Szczepaniak, Jan; Tanaś, Wojciech; Kromulski, Jacek

    2014-01-01

    Many people are exposed to whole-body vibration (WBV) in their occupational lives, especially drivers of vehicles such as tractor and trucks. The main categories of effects from WBV are perception degraded comfort interference with activities-impaired health and occurrence of motion sickness. Absorbed power is defined as the power dissipated in a mechanical system as a result of an applied force. The vibration-induced injuries or disorders in a substructure of the human system are primarily associated with the vibration power absorption distributed in that substructure. The vibration power absorbed by the exposed body is a measure that combines both the vibration hazard and the biodynamic response of the body. The article presents measurement method for determining vibration power dissipated in the human whole body system called Vibration Energy Absorption (VEA). The vibration power is calculated from the real part of the force-velocity cross-spectrum. The absorbed power in the frequency domain can be obtained from the cross-spectrum of the force and velocity. In the context of the vibration energy transferred to a seated human body, the real component reflects the energy dissipated in the biological structure per unit of time, whereas the imaginary component reflects the energy stored/released by the system. The seated human is modeled as a series/parallel 4-DOF dynamic models. After introduction of the excitation, the response in particular segments of the model can be analyzed. As an example, the vibration power dissipated in an operator has been determined as a function of the agricultural combination operating speed 1.39 - 4.16 ms(-1).

  8. Vibration energy absorption in the whole-body system of a tractor operator

    Directory of Open Access Journals (Sweden)

    Jan Szczepaniak

    2014-06-01

    Full Text Available Many people are exposed to whole-body vibration (WBV in their occupational lives, especially drivers of vehicles such as tractor and trucks. The main categories of effects from WBV are perception degraded comfort interference with activities-impaired health and occurrence of motion sickness. Absorbed power is defined as the power dissipated in a mechanical system as a result of an applied force. The vibration-induced injuries or disorders in a substructure of the human system are primarily associated with the vibration power absorption distributed in that substructure. The vibration power absorbed by the exposed body is a measure that combines both the vibration hazard and the biodynamic response of the body. The article presents measurement method for determining vibration power dissipated in the human whole body system called Vibration Energy Absorption (VEA. The vibration power is calculated from the real part of the force-velocity cross-spectrum. The absorbed power in the frequency domain can be obtained from the cross-spectrum of the force and velocity. In the context of the vibration energy transferred to a seated human body, the real component reflects the energy dissipated in the biological structure per unit of time, whereas the imaginary component reflects the energy stored/released by the system. The seated human is modeled as a series/parallel 4-DOF dynamic models. After introduction of the excitation, the response in particular segments of the model can be analyzed. As an example, the vibration power dissipated in an operator has been determined as a function of the agricultural combination operating speed 1.39 – 4.16 ms[sup] -1 [/sup].

  9. Monitoring of elemental composition of honey from selected regions of Ghana using Instrumental Neutron Activation Analysis and Atomic Absorption Spectroscopy

    International Nuclear Information System (INIS)

    Boateng, R.

    2015-01-01

    Honey is a sweet, thick and viscid fluid collected from beehives and usually found in cells of the honey comb. It is produced from nectar collected from various flowers by honeybees and processed. Among the important uses, pure and undiluted honey serves as natural sweetener and contains a broad variety of vitamins for human consumption. Due to its global demand, monitoring of the quality of honey is of great significance. In this study, honey samples were collected systematically from farmers and retailers in the Brong Ahafo, Ashanti and Greater Accra regions of Ghana. The sampling was done along the farmer-to-trader channels, to assess the quality of honey produced from various regions and to trace the sources of elemental contamination. Physicochemical studies; pH, electrical conductivity and specific gravity were done. The levels of selected toxic heavy metals (Hg, Pb, Cd, V, Cr, As) and essential metals (K, Na, Ca, Mg, Mn, Cu, Fe, Co) in the honey samples were analysed using instrumental neutron activation analysis (INAA). Flame atomic absorption spectrophotometry (FAAS) was also employed to determine elements such as Pb, Co, Cr and Fe. All the honey samples were found to be acidic, with pH ranging from 3.60 to 6.10. The acidity of honey is significant as it inhibits the growth of microorganisms. The values agrees favourably with the permitted pH limits of 3.40 to 3.60 for good quality honey, set by the National Honey Board of United States. The electrical conductivities measured ranged from 11.9 μS/cm to 44.4 μS/cm. The values were within the acceptable limits set by Ghana Standards Authority and other organizations (<800 μS/cm). The specific gravity of the honey samples analysed ranged from 1.297 to 2.031. These values were higher than the values (1.2081 to 1.2270) reported in Libyan Honey. However, these values were closer to the average specific gravity (1.425) value reported in other studies. These variations in the specific gravity may be related to

  10. Experimental analysis of a diffusion absorption refrigeration system used alternative energy sources

    International Nuclear Information System (INIS)

    Soezen, A.; Oezbas, E.

    2009-01-01

    The continuous-cycle absorption refrigeration device is widely used in domestic refrigerators, and recreational vehicles. It is also used in year-around air conditioning of both homes and larger buildings. The unit consists of four main parts the boiler, condenser, evaporator and the absorber. When the unit operates on kerosene or gas, the heat is supplied by a burner. This element is fitted underneath the central tube. When operating on electricity, the heat is supplied by an element inserted in the pocket. No moving parts are employed. The operation of the refrigerating mechanism is based on Dalton's law. In this study, experimental analysis was performed of a diffusion absorption refrigeration system (DARS) used alternative energy sources such as solar, liquid petroleum gas (LPG) sources. Two basic DAR cycles were set up and investigated: i) In the first cycle (DARS-1), the condensate is sub-cooled prior to the evaporator entrance by the coupled evaporator/gas heat exchanger similar with manufactured by Electrolux Sweden. ii) In the second cycle (DARS-2), the condensate is not sub-cooled prior to the evaporator entrance and gas heat exchanger is separated from the evaporator. (author)

  11. Open-ended response theory with polarizable embedding: multiphoton absorption in biomolecular systems.

    Science.gov (United States)

    Steindal, Arnfinn Hykkerud; Beerepoot, Maarten T P; Ringholm, Magnus; List, Nanna Holmgaard; Ruud, Kenneth; Kongsted, Jacob; Olsen, Jógvan Magnus Haugaard

    2016-10-12

    We present the theory and implementation of an open-ended framework for electric response properties at the level of Hartree-Fock and Kohn-Sham density functional theory that includes effects from the molecular environment modeled by the polarizable embedding (PE) model. With this new state-of-the-art multiscale functionality, electric response properties to any order can be calculated for molecules embedded in polarizable atomistic molecular environments ranging from solvents to complex heterogeneous macromolecules such as proteins. In addition, environmental effects on multiphoton absorption (MPA) properties can be studied by evaluating single residues of the response functions. The PE approach includes mutual polarization effects between the quantum and classical parts of the system through induced dipoles that are determined self-consistently with respect to the electronic density. The applicability of our approach is demonstrated by calculating MPA strengths up to four-photon absorption for the green fluorescent protein. We show how the size of the quantum region, as well as the treatment of the border between the quantum and classical regions, is crucial in order to obtain reliable MPA predictions.

  12. Molecular dynamics simulation of a nanofluidic energy absorption system: effects of the chiral vector of carbon nanotubes.

    Science.gov (United States)

    Ganjiani, Sayed Hossein; Hossein Nezhad, Alireza

    2018-02-14

    A Nanofluidic Energy Absorption System (NEAS) is a novel nanofluidic system with a small volume and weight. In this system, the input mechanical energy is converted to surface tension energy during liquid infiltration in the nanotube. The NEAS is made of a mixture of nanoporous material particles in a functional liquid. In this work, the effects of the chiral vector of a carbon nanotube (CNT) on the performance characteristics of the NEAS are investigated by using molecular dynamics simulation. For this purpose, six CNTs with different diameters for each type of armchair, zigzag and chiral, and several chiral CNTs with different chiral vectors (different values of indices (m,n)) are selected and studied. The results show that in the chiral CNTs, the contact angle shows the hydrophobicity of the CNT, and infiltration pressure is reduced by increasing the values of m and n (increasing the CNT diameter). Contact angle and infiltration pressure are decreased by almost 1.4% and 9% at all diameters, as the type of CNT is changed from chiral to zigzag and then to armchair. Absorbed energy density and efficiency are also decreased by increasing m and n and by changing the type of CNT from chiral to zigzag and then to armchair.

  13. Tri-generation System based on Municipal Waste Gasification, Fuel Cell and an Absorption Chiller

    Directory of Open Access Journals (Sweden)

    Giannis Katsaros

    2018-03-01

    Full Text Available The present work focuses on the design of a novel tri-generation system based on gasification of municipal solid wastes, a solid oxide fuel cell and an ammonia-water absorption chiller. Tri-generation systems can be implemented in buildings such as hospitals and hotels, where there is a continuous and large demand for electricity, heating and cooling. The system is modelled in Aspen Plus and the influence of different operating parameters on the system performance was studied. The findings suggest that low air equivalent ratios and high gasification temperatures enhance the overall system performance. Syngas cleaning with metal sorbents zinc oxide and sodium bicarbonate for the removal of hydrogen sulfide and hydrogen chloride concentrations proved to be very effective, reducing the concentration of contaminants to < 1 ppm (part per million levels. The possibility of covering the demand profiles of a specific building was also investigated: the system could fully meet the electricity and cooling demands, whereas the heat requirements could be satisfied only up to 55%. Moreover, assuming 20 years of operation, the payback period was 4.5 years and the net present value exceeded 5 million euros.

  14. Experimental investigation on charging and discharging performance of absorption thermal energy storage system

    International Nuclear Information System (INIS)

    Zhang, Xiaoling; Li, Minzhi; Shi, Wenxing; Wang, Baolong; Li, Xianting

    2014-01-01

    Highlights: • A prototype of ATES using LiBr/H 2 O was designed and built. • Charging and discharging performances of ATES system were investigated. • ESE and ESD for cooling, domestic hot water and heating were obtained. - Abstract: Because of high thermal storage density and little heat loss, absorption thermal energy storage (ATES) is known as a potential thermal energy storage (TES) technology. To investigate the performance of the ATES system with LiBr–H 2 O, a prototype with 10 kW h cooling storage capacity was designed and built. The experiments demonstrated that charging and discharging processes are successful in producing 7 °C chilled water, 65 °C domestic hot water, or 43 °C heating water to meet the user’s requirements. Characteristics such as temperature, concentration and power variation of the ATES system during charging and discharging processes were investigated. The performance of the ATES system for supplying cooling, heating or domestic hot water was analyzed and compared. The results indicate that the energy storage efficiencies (ESE) for cooling, domestic hot water and heating are 0.51, 0.97, 1.03, respectively, and the energy storage densities (ESD) for cooling, domestic hot water and heating reach 42, 88, 110 kW h/m 3 , respectively. The performance is better than those of previous TES systems, which proves that the ATES system using LiBr–H 2 O may be a good option for thermal energy storage

  15. Safety, tolerability, and systemic absorption of dapivirine vaginal microbicide gel in healthy, HIV-negative women.

    Science.gov (United States)

    Nel, Annalene M; Coplan, Paul; van de Wijgert, Janneke H; Kapiga, Saidi H; von Mollendorf, Claire; Geubbels, Eveline; Vyankandondera, Joseph; Rees, Helen V; Masenga, Gileard; Kiwelu, Ireen; Moyes, Jocelyn; Smythe, Shanique C

    2009-07-31

    To assess the local and systemic safety of dapivirine vaginal gel vs. placebo gel as well as the systemic absorption of dapivirine in healthy, HIV-negative women. Two prospective, randomized, double-blind, placebo-controlled phase I/II studies were conducted at five research centers, four in Africa and one in Belgium. A total of 119 women used dapivirine gel (concentrations of 0.001, 0.002, 0.005, or 0.02%), and 28 used placebo gel twice daily for 42 days. The primary endpoints were colposcopic findings, adverse events, Division of AIDS grade 3 or grade 4 laboratory values, and plasma levels of dapivirine. Safety data were similar for the dapivirine and placebo gels. None of the adverse events with incidence more than 5% occurred with greater frequency in the dapivirine than placebo groups. Similar percentages of placebo and dapivirine gel users had adverse events that were considered by the investigator to be related to study gel. A total of five serious adverse events occurred in the two studies, and none was assessed as related to study gel. Mean plasma concentrations of dapivirine were approximately dose proportional, and, within each dose group, mean concentrations were similar on days 7, 28, and 42. The maximum observed mean concentration was 474 pg/ml in the 0.02% gel group on day 28. Two weeks after the final application of study gel, mean concentrations decreased to 5 pg/ml or less. Twice daily administration of dapivirine vaginal gel for 42 days was safe and well tolerated with low systemic absorption in healthy, HIV-negative women suggesting that continued development is warranted.

  16. Second law-based thermodynamic analysis of water-lithium bromide absorption refrigeration system

    Energy Technology Data Exchange (ETDEWEB)

    Kilic, Muhsin [Department of Mechanical Engineering, Faculty of Engineering and Architecture, Uludag University, TR 16059, Bursa (Turkey)]. E-mail: mkilic@uludag.edu.tr; Kaynakli, Omer [Department of Mechanical Engineering, Faculty of Engineering and Architecture, Uludag University, TR 16059, Bursa (Turkey)

    2007-08-15

    In this study, the first and the second law of thermodynamics are used to analyze the performance of a single-stage water-lithium bromide absorption refrigeration system (ARS) when some working parameters are varied. A mathematical model based on the exergy method is introduced to evaluate the system performance, exergy loss of each component and total exergy loss of all the system components. Parameters connected with performance of the cycle-circulation ratio (CR), coefficient of performance (COP), Carnot coefficient of performance (COP{sub c} ), exergetic efficiency ({xi}) and efficiency ratio ({tau})-are calculated from the thermodynamic properties of the working fluids at various operating conditions. Using the developed model, the effect of main system temperatures on the performance parameters of the system, irreversibilities in the thermal process and non-dimensional exergy loss of each component are analyzed in detail. The results show that the performance of the ARS increases with increasing generator and evaporator temperatures, but decreases with increasing condenser and absorber temperatures. Exergy losses in the expansion valves, pump and heat exchangers, especially refrigerant heat exchanger, are small compared to other components. The highest exergy loss occurs in the generator regardless of operating conditions, which therefore makes the generator the most important component of the cycle.

  17. Second law-based thermodynamic analysis of water-lithium bromide absorption refrigeration system

    International Nuclear Information System (INIS)

    Kilic, Muhsin; Kaynakli, Omer

    2007-01-01

    In this study, the first and the second law of thermodynamics are used to analyze the performance of a single-stage water-lithium bromide absorption refrigeration system (ARS) when some working parameters are varied. A mathematical model based on the exergy method is introduced to evaluate the system performance, exergy loss of each component and total exergy loss of all the system components. Parameters connected with performance of the cycle-circulation ratio (CR), coefficient of performance (COP), Carnot coefficient of performance (COP c ), exergetic efficiency (ξ) and efficiency ratio (τ)-are calculated from the thermodynamic properties of the working fluids at various operating conditions. Using the developed model, the effect of main system temperatures on the performance parameters of the system, irreversibilities in the thermal process and non-dimensional exergy loss of each component are analyzed in detail. The results show that the performance of the ARS increases with increasing generator and evaporator temperatures, but decreases with increasing condenser and absorber temperatures. Exergy losses in the expansion valves, pump and heat exchangers, especially refrigerant heat exchanger, are small compared to other components. The highest exergy loss occurs in the generator regardless of operating conditions, which therefore makes the generator the most important component of the cycle

  18. Theoretical study on the effect of operating conditions on performance of absorption refrigeration system

    Energy Technology Data Exchange (ETDEWEB)

    Kaynakli, Omer; Kilic, Muhsin [Uludag University, Faculty of Engineering and Architecture, Department of Mechanical Engineering, TR-16059, Bursa (Turkey)

    2007-02-15

    In this study, a detailed thermodynamic analysis of the water/lithium bromide absorption refrigeration cycle is performed. The influences of operating temperature and effectiveness of heat exchanger on the thermal loads of components, coefficients of performance (COP{sub c}, COP) and efficiency ratio ({eta}) are investigated. It is concluded that the COP{sub c} and COP values increase with increasing generator and evaporator temperatures but decrease with increasing condenser and absorber temperatures. The {eta} value varies with these temperatures. Also, the effects of solution and refrigerant heat exchangers on the performance, efficiency ratio of the system and fluid temperatures are compared. As a result, it is found that the solution heat exchanger (SHE) has more effect on the investigated parameters than the refrigerant heat exchanger (RHE). While the SHE increases the COP value up to a maximum 44%, the RHE has an effect of only 2.8%. (author)

  19. Study of laser radar system using the differential absorption method for detection of air pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Inomata, H; Igarashi, T

    1975-11-01

    A laser radar system using the differential absorption method for remote measurement of atmospheric NO/sub 2/ and SO/sub 2/ is studied. A simultaneous two-wavelength dye laser for the transmitter and a simultaneous two-wavelength signal processer for the receiver are developed. In using this technique, one laser shot allows the determination of NO/sub 2/ concentrations with an uncertainty equivalent to 44 ppM times the range interval (in meters). It seems that the technique is most promising for a range-resolved measurement of ambient molecular pollutants, since it has the advantage of canceling the effect of atmospheric variation in a measurement when atmospheric aerosols are used as a distributed reflector.

  20. Comparative study of irreversibilities in an aqua-ammonia absorption refrigeration system

    Energy Technology Data Exchange (ETDEWEB)

    Ataer, O E [Gazi Univ., Ankara (TR). Mechanical Engineering Dept.; Gogus, Y [Middle East Technical Univ., Ankara (Turkey)

    1991-03-01

    Irreversibilities in components of an aqua-ammonia absorption refrigeration system (ARS) have been determined by second law analysis. The components of the ARS are as follows: condenser, evaporator, absorber, generator, pump, expansion valves, mixture heat exchanger and refrigerant heat exchanger. It is assumed that the ammonia concentration at the generator exit is, independent of the other parameters, equal to 0.999 and at the evaporator exit the gas is saturated vapour. Pressure losses between the generator and condenser, and the evaporator and absorber are taken into consideration. In the results the dimensionless exergy loss of each component, the exergetic coefficient of performance, the coefficient of performance and the circulation ratio are given graphically for each different generator, evaporator, condenser and absorber temperature. (author).

  1. ERP systems selection in multinational enterprises: a practical guide

    OpenAIRE

    Moutaz Haddara

    2018-01-01

    The Enterprise Resource Planning (ERP) system selection is an early phase in the ERP adoption process. When organizations evaluate an ERP, they commonly develop their own selection criteria that usually involve various system and vendor related factors. While the selection process is critical, however, there is an apparent research gap in literature. The ERP selection effort also focuses on the system’s fit with the organizational requirements and needs. Thus, the selection phase is critical,...

  2. Research on ration selection of mixed absorbent solution for membrane air-conditioning system

    International Nuclear Information System (INIS)

    Li, Xiu-Wei; Zhang, Xiao-Song; Wang, Fang; Zhao, Xiao; Zhang, Zhuo

    2015-01-01

    Highlights: • We derive models of the membrane air-conditioning system with mixed absorbents. • We make analysis on system COP, cost-effectiveness and economy. • The paper provides a new method for ideal absorbent selection. • The solutes concentration of 50% achieves the best cost-effectiveness and the economy. - Abstract: Absorption air-conditioning system is a good alternative to vapor compression system for developing low carbon society. To improve the performance of the traditional absorption system, the membrane air-conditioning system is configured and its COP can reach as high as 6. Mixed absorbents are potential for cost reduction of the membrane system while maintaining a high COP. On the purpose of finding ideal mixed absorbent groups, this paper makes analysis on COP, cost-effectiveness and economy of the membrane system with mixed LiBr–CaCl 2 absorbent solution. The models of the system have been developed for the analysis. The results show the COP is higher for the absorbent groups with lower concentration of the total solute and higher concentration ratio of LiBr. It also reveals when the total solutes concentration is about 50%, it achieves the best cost-effectiveness and the economy. The process of the analysis provides a useful method for mixed absorbents selection

  3. Ab-initio calculations of the hydrogen-uranium system: Surface phenomena, absorption, transport and trapping

    International Nuclear Information System (INIS)

    Taylor, Christopher D.; Scott Lillard, R.

    2009-01-01

    Density functional theory was applied to the initial steps of uranium hydriding: surface phenomena, absorption, bulk transport and trapping. H adsorbs exothermically to the (0 0 1) surface, yet H absorption into the bulk is endothermic, with off-center octahedral absorption having the lowest absorption energy of 0.39 eV, relative to molecular H 2 . H absorption in interstitial sites causes a local softening of the bulk modulus. Diffusion of H in unstrained α-U has a barrier of 0.6 eV. The energy of H absorption adjacent to the chemical impurities C, S, Si was lowered by an amount proportional to the size of the impurity atom, and the resulting lattice strain Si > S > C. Thus, impurities may promote hydriding by providing surfaces or prestrained zones for H uptake.

  4. System driven technology selection for future European launch systems

    Science.gov (United States)

    Baiocco, P.; Ramusat, G.; Sirbi, A.; Bouilly, Th.; Lavelle, F.; Cardone, T.; Fischer, H.; Appel, S.

    2015-02-01

    In the framework of the next generation launcher activity at ESA, a top-down approach and a bottom-up approach have been performed for the identification of promising technologies and alternative conception of future European launch vehicles. The top-down approach consists in looking for system-driven design solutions and the bottom-up approach features design solutions leading to substantial advantages for the system. The main investigations have been focused on the future launch vehicle technologies. Preliminary specifications have been used in order to permit sub-system design to find the major benefit for the overall launch system. The development cost, non-recurring and recurring cost, industrialization and operational aspects have been considered as competitiveness factors for the identification and down-selection of the most interesting technologies. The recurring cost per unit payload mass has been evaluated. The TRL/IRL has been assessed and a preliminary development plan has been traced for the most promising technologies. The potentially applicable launch systems are Ariane and VEGA evolution. The main FLPP technologies aim at reducing overall structural mass, increasing structural margins for robustness, metallic and composite containment of cryogenic hydrogen and oxygen propellants, propellant management subsystems, elements significantly reducing fabrication and operational costs, avionics, pyrotechnics, etc. to derive performing upper and booster stages. Application of the system driven approach allows creating performing technology demonstrators in terms of need, demonstration objective, size and cost. This paper outlines the process of technology down selection using a system driven approach, the accomplishments already achieved in the various technology fields up to now, as well as the potential associated benefit in terms of competitiveness factors.

  5. ARTIFICIAL NEURAL NETWORKS BASED GEARS MATERIAL SELECTION HYBRID INTELLIGENT SYSTEM

    Institute of Scientific and Technical Information of China (English)

    X.C. Li; W.X. Zhu; G. Chen; D.S. Mei; J. Zhang; K.M. Chen

    2003-01-01

    An artificial neural networks(ANNs) based gear material selection hybrid intelligent system is established by analyzing the individual advantages and weakness of expert system (ES) and ANNs and the applications in material select of them. The system mainly consists of tow parts: ES and ANNs. By being trained with much data samples,the back propagation (BP) ANN gets the knowledge of gear materials selection, and is able to inference according to user input. The system realizes the complementing of ANNs and ES. Using this system, engineers without materials selection experience can conveniently deal with gear materials selection.

  6. Portable ultrahigh-vacuum sample storage system for polarization-dependent total-reflection fluorescence x-ray absorption fine structure spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Yoshihide, E-mail: e0827@mosk.tytlabs.co.jp; Nishimura, Yusaku F.; Suzuki, Ryo; Beniya, Atsushi; Isomura, Noritake [Toyota Central R& D Labs., Inc., Yokomichi 41-1, Nagakute, Aichi 480-1192 (Japan); Uehara, Hiromitsu; Asakura, Kiyotaka; Takakusagi, Satoru [Catalysis Research Center, Hokkaido University, Kita 21-10, Sapporo, Hokkaido 001-0021 (Japan); Nimura, Tomoyuki [AVC Co., Ltd., Inada 1450-6, Hitachinaka, Ibaraki 312-0061 (Japan)

    2016-03-15

    A portable ultrahigh-vacuum sample storage system was designed and built to investigate the detailed geometric structures of mass-selected metal clusters on oxide substrates by polarization-dependent total-reflection fluorescence x-ray absorption fine structure spectroscopy (PTRF-XAFS). This ultrahigh-vacuum (UHV) sample storage system provides the handover of samples between two different sample manipulating systems. The sample storage system is adaptable for public transportation, facilitating experiments using air-sensitive samples in synchrotron radiation or other quantum beam facilities. The samples were transferred by the developed portable UHV transfer system via a public transportation at a distance over 400 km. The performance of the transfer system was demonstrated by a successful PTRF-XAFS study of Pt{sub 4} clusters deposited on a TiO{sub 2}(110) surface.

  7. Solar-assisted absorption air-conditioning systems in buildings: Control strategies and operational modes

    International Nuclear Information System (INIS)

    Shirazi, Ali; Pintaldi, Sergio; White, Stephen D.; Morrison, Graham L.; Rosengarten, Gary; Taylor, Robert A.

    2016-01-01

    Highlights: • A simulation model of a solar driven absorption chiller is developed in detail. • Three control strategies were proposed in the solar loop of the plant. • Series and parallel auxiliary heater arrangements were investigated. • The results showed the auxiliary-heater in parallel outperformed the series one. • Solar fraction can be increased by 20% by implementing the proposed configuration. - Abstract: Solar-assisted cooling technology has enormous potential for air-conditioning applications since both solar energy supply and cooling energy demand are well correlated. Unfortunately, market uptake of solar cooling technologies has been slow due to the high capital cost and limited design/operational experience. In the present work, different designs and operational modes for solar heating and cooling (SHC) absorption chiller systems are investigated and compared in order to identify the preferred design strategies for these systems. Three control scenarios are proposed for the solar collector loop. The first uses a constant flow pump, while the second and third control schemes employ a variable speed pump, where the solar collector (SC) set-point temperature could be either fixed or adjusted to the required demand. Series and parallel arrangements, between the auxiliary heater and the storage tank, have been examined in detail from an energy efficiency perspective. A simulation model for different system layouts is developed in the transient system simulation environment (TRNSYS, Version 17). Simulation results revealed that the total solar fraction of the plant is increased by up to 11% when a variable speed solar loop pump is used to achieve a collector set-point temperature adjusted according to the building load demand. Another significant finding of this study is that a parallel configuration for the auxiliary heater out-performs a conventional series configuration. The yearly performance of an auxiliary heater in parallel with the storage

  8. Cardiovascular safety of the oral controlled absorption system (OCAS) formulation of tamsulosin compared to the modified release (MR) formulation

    NARCIS (Netherlands)

    Michel, M. C.; Korstanje, C.; Klauwinkel, W.; Shear, M.; Davies, J.; Quartel, A.

    2005-01-01

    Objective: The potential to interfere with efferent adrenergic drive in the cardiovascular system was tested in elderly healthy subjects for the new oral controlled absorption system (OCAS) 0.4 mg tablet formulation of tamsulosin compared to the modified release (MR) 0.4 mg capsule formulation of

  9. Measurement of Electronic States of PbS Nanocrystal Quantum Dots Using Scanning Tunneling Spectroscopy: The Role of Parity Selection Rules in Optical Absorption

    Science.gov (United States)

    Diaconescu, Bogdan; Padilha, Lazaro A.; Nagpal, Prashant; Swartzentruber, Brian S.; Klimov, Victor I.

    2013-03-01

    We study the structure of electronic states in individual PbS nanocrystal quantum dots by scanning tunneling spectroscopy (STS) using one-to-two monolayer nanocrystal films treated with 1, 2-ethanedithiols (EDT). Up to six individual valence and conduction band states are resolved for a range of quantum dot sizes. The measured states’ energies are in good agreement with calculations using the k·p four-band envelope function formalism. A comparison of STS and optical absorption spectra indicates that some of the absorption features can only be explained by asymmetric transitions involving the states of different symmetries (e.g., S and P or P and D), which points towards the relaxation of the parity selection rules in these nanostructures. STS measurements also reveal a midgap feature, which is likely similar to one observed in previous charge transport studies of EDT-treated quantum dot films.

  10. Advanced Sine Wave Modulation of Continuous Wave Laser System for Atmospheric CO2 Differential Absorption Measurements

    Science.gov (United States)

    Campbell, Joel F.; Lin, Bing; Nehrir, Amin R.

    2014-01-01

    NASA Langley Research Center in collaboration with ITT Exelis have been experimenting with Continuous Wave (CW) laser absorption spectrometer (LAS) as a means of performing atmospheric CO2 column measurements from space to support the Active Sensing of CO2 Emissions over Nights, Days, and Seasons (ASCENDS) mission.Because range resolving Intensity Modulated (IM) CW lidar techniques presented here rely on matched filter correlations, autocorrelation properties without side lobes or other artifacts are highly desirable since the autocorrelation function is critical for the measurements of lidar return powers, laser path lengths, and CO2 column amounts. In this paper modulation techniques are investigated that improve autocorrelation properties. The modulation techniques investigated in this paper include sine waves modulated by maximum length (ML) sequences in various hardware configurations. A CW lidar system using sine waves modulated by ML pseudo random noise codes is described, which uses a time shifting approach to separate channels and make multiple, simultaneous online/offline differential absorption measurements. Unlike the pure ML sequence, this technique is useful in hardware that is band pass filtered as the IM sine wave carrier shifts the main power band. Both amplitude and Phase Shift Keying (PSK) modulated IM carriers are investigated that exibit perfect autocorrelation properties down to one cycle per code bit. In addition, a method is presented to bandwidth limit the ML sequence based on a Gaussian filter implemented in terms of Jacobi theta functions that does not seriously degrade the resolution or introduce side lobes as a means of reducing aliasing and IM carrier bandwidth.

  11. Experimental study on a project with CHP system basing on absorption cycles

    International Nuclear Information System (INIS)

    Sun, Jian; Fu, Lin; Sun, Fangtian; Zhang, Shigang

    2014-01-01

    A new heat recovery system for the CHP (combined heating and power) is presented, and HRU (heat recovery unit) and AHE (absorption heat exchanger) are invented to improve the total energy efficiency of the conventional CHP system by more than 20%, which are installed at the thermal power plant and the heating substation separately. The HRU could recover the low grade heat of exhausted steam from the turbine directly, and the AHE could decrease the temperature of back water of primary pipe to a lower temperature than that of secondary pipe without changing the flow rate of secondary pipe. A large demonstration project employing this technology has been built in Datong of China. And experimental results of HRU and AHE are presented to evaluate this system. - Highlights: • The total energy efficiency of CHP could by increased by more than 20%. • Temperature of back water of primary pipe could be lower than that of secondary pipe. • Heating capacity of primary pipe could be increased significantly. • Low grade heat of exhausted steam from turbine could be recovered directly

  12. 46 CFR 108.404 - Selection of fire detection system.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Selection of fire detection system. 108.404 Section 108... DESIGN AND EQUIPMENT Fire Extinguishing Systems § 108.404 Selection of fire detection system. (a) If a... space. (b) The fire detection system must be designed to minimize false alarms. ...

  13. Combining selective sequential extractions, X-Ray Absorption Spectroscopy, and X-Ray Powder Diffraction for Cu (II speciation in soil and mineral phases

    Directory of Open Access Journals (Sweden)

    Tatiana Minkina

    2017-04-01

    Full Text Available Interaction of Cu (II ions with the matrix of soil and mineral phases of layered silicates was assessed by the Miller method of selective sequential fractionation and a set of synchrotron X-ray methods, including X-ray powder diffraction (XRD and X-ray absorption spectroscopy (XANES. It was shown that the input of Cu into Calcic Chernozem in the form of monoxide (CuO and salt (Cu(NO32 affected the transformation of Cu compounds and their affinity for metal-bearing phases. It was found that the contamination of soil with a soluble Cu(II salt increased the bioavailability of the metal and the role of organic matter and Fe oxides in the fixation and retention of Cu. During the incubation of soil with Cu monoxide, the content of the metal in the residual fractions increased, which was related to the possible entry of Cu in the form of isomorphic impurities into silicates, as well as to the incomplete dissolution of exogenic compounds at the high level of their input into the soil. A mechanism for the structural transformation of minerals was revealed, which showed that ion exchange processes result in the sorption of Cu (II ions from the saturated solution by active sites on the internal surface of the lattice of dioctahedral aluminosilicates. Surface hydroxyls at the octahedral aluminum atom play the main role. X-ray diagnostics revealed that excess Cu(II ions are removed from the system due to the formation and precipitation of coarsely crystalline Cu(NO3(OH3.

  14. Modelling the effect of oil/fat content in food systems on flavour absorption by LLDPE.

    NARCIS (Netherlands)

    Dekker, M.; Willige, van R.W.G.; Linssen, J.P.H.; Voragen, A.G.J.

    2003-01-01

    One of the phenomena in food packaging interactions is flavour absorption. Absorption of flavour compounds from food products into food-packaging materials can result in loss of flavour compounds or an unbalance in the flavour profile changing a product's quality. The food matrix influences the

  15. Evaluation of systemic absorption and renal effects of topical ophthalmic flurbiprofen and diclofenac in healthy cats.

    Science.gov (United States)

    Lanuza, Rick; Rankin, Amy J; KuKanich, Butch; Meekins, Jessica M

    2016-07-01

    To investigate systemic absorption and renal effects of topically applied ophthalmic flurbiprofen and diclofenac in healthy cats. Twelve domestic shorthair cats. Cats were randomly assigned to two treatment groups (n = 6) and administered one drop (approximately 40 μL) of either flurbiprofen 0.03% or diclofenac 0.1% in both eyes four times daily (6 am, 12 pm, 6 pm, and 12 am) for 14 days. Blood samples were collected on days 0, 4, 8, 14, 16, and 17 and analyzed by liquid chromatography and mass spectrometry for flurbiprofen and diclofenac plasma concentrations. A complete blood count (CBC), serum chemistry, and urinalysis were analyzed at the beginning of the study (Day 0) and at the end of topical drug administration (Day 15). Both drugs demonstrated systemic absorption. Flurbiprofen was detected (mean ± SD) at day 4 (237 ± 65 ng/mL), day 8 (396 ± 91 ng/mL), day 14 (423 ± 56 ng/mL), day 16 (350 ± 66 ng/mL), and day 17 (270 ± 62 ng/mL), and diclofenac was detected (mean ± SD) at day 4 (130 ± 44 ng/mL), day 8 (131 ± 25 ng/mL), day 14 (150 ± 36 ng/mL), and sporadically on day 16 [corrected]. Flurbiprofen plasma concentration decreased slowly over 48 h after the last dose. No clinically significant abnormalities were noted in the serum blood urea nitrogen, creatinine, or urine specific gravity at the end of topical drug administration compared to the beginning of the study. Flurbiprofen and diclofenac were systemically absorbed after topical administration four times daily to both eyes of healthy cats. Flurbiprofen reached higher plasma concentrations compared to diclofenac. © 2015 American College of Veterinary Ophthalmologists.

  16. A Faraday rotation search for magnetic fields in quasar damped Ly alpha absorption systems

    Science.gov (United States)

    Oren, Abraham L.; Wolfe, Arthur M.

    1995-01-01

    We present the results of a Faraday rotation survey of 61 radio-bright QSOs conducted at the National Radio Astronomy Observatory (NRAO) Very Large Array (VLA). The Galactic contribution to the Faraday rotation is estimated and subtracted to determine the extragalactic rotation measure (RRM) for each source. Eleven of these QSOs are known to exhibit damped Ly alpha absorption. The rate of incidence of significant Faraday rotation of these 11 sources is compared to the remaining 50 and is found to be higher at the 99.8% confidence level. However, as this is based upon only two detections of Faraday rotation in the damped Ly alpha sample, the result is only tentative. If the two detections in the damped Ly alpha sample are dug to the absorbing systems, then the inferred rotation measure induced by these systems is roughly 250 rad/sq m. The two detections were for the two lowest redshift absorbers in the sample. We find that a rotation measure of 250 rad/sq m would have gone undetected for any other absorber in the damped Ly alpha sample due to the 1/(1 + 2) squared dilution of the observed RRM with redshift. Thus the data are consistent with, but do not prove, the hypothesis that Faraday rotation is a generic property of damped Ly alpha absorbers. We do not confirm the suggestion that the amplitude of RRMs increases with redshift. Rather, the data are consistent with no redshift evolution. We find that the uncertainty in the estimation of the Galactic rotation measure (GRM) is a more serious problem than previously realized for extra-galactic Faraday rotation studies of QSO absorbers. A careful analysis of current methods for estimating GRM indicate that it can be determined to an accuracy of about 15 - 20 rad/sq m. Previous studies underestimated this uncertainty by more than a factor of 2. Due to this uncertainty, rotation measures such as we suspect are associated with damped Ly alpha absorption systems can only be detected at redshifts less than z approximately

  17. SODIUM ABSORPTION SYSTEMS TOWARD SN Ia 2014J ORIGINATE ON INTERSTELLAR SCALES

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, K.; Nogami, D. [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Tajitsu, A. [Subaru Telescope, National Astronomical Observatory of Japan, 650 North A’ohoku Place, Hilo, HI 96720 (United States); Kawabata, K. S. [Hiroshima Astrophysical Science Center, Hiroshima University, Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Foley, R. J. [Astronomy Department, University of Illinois at Urbana-Champaign, 1002 W. Green Street, Urbana, IL 61801 (United States); Honda, S.; Arai, A. [Nishi-Harima Astronomical Observatory, Center for Astronomy, University of Hyogo, 407-2, Nishigaichi, Sayo-cho, Sayo, Hyogo 679-5313 (Japan); Moritani, Y.; Ishigaki, M.; Nomoto, K.; Schramm, M. [Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Tanaka, M.; Aoki, W. [National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan); Hashimoto, O. [Gunma Astronomical Observatory, Takayama, Gunma 377-0702 (Japan); Simon, J. D. [Observatories of the Carnegie Institution for Science, 813 Santa Barbara St, Pasadena, CA 91101 (United States); Phillips, M. M. [Carnegie Observatories, Las Campanas Observatory, Casilla 601, La Serena (Chile); Yamanaka, M. [Department of Physics, Faculty of Science and Engineering, Konan University, Okamoto, Kobe, Hyogo 658-8501 (Japan); Milisavljevic, D.; Soderberg, A. M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Mazzali, P. A., E-mail: keiichi.maeda@kusastro.kyoto-u.ac.jp [Astrophysics Research Institute, Liverpool John Moores University, Liverpool L3 5RF (United Kingdom); and others

    2016-01-10

    Na i D absorbing systems toward Type Ia supernovae (SNe Ia) have been intensively studied over the last decade with the aim of finding circumstellar material (CSM), which is an indirect probe of the progenitor system. However, it is difficult to deconvolve CSM components from non-variable, and often dominant, components created by interstellar material (ISM). We present a series of high-resolution spectra of SN Ia 2014J from before maximum brightness to ≳250 days after maximum brightness. The late-time spectrum provides unique information for determining the origin of the Na i D absorption systems. The deep late-time observation allows us to probe the environment around the SN at a large scale, extending to ≳40 pc. We find that a spectrum of diffuse light in the vicinity, but not directly in the line of sight, of the SN has absorbing systems nearly identical to those obtained for the “pure” SN line of sight. Therefore, basically all Na i D systems seen toward SN 2014J must originate from foreground material that extends to at least ∼40 pc in projection and none at the CSM scale. A fluctuation in the column densities at a scale of ∼20 pc is also identified. After subtracting the diffuse, “background” spectrum, the late-time Na i D profile along the SN line of sight is consistent with profiles near maximum brightness. The lack of variability on a ∼1 year timescale is consistent with the ISM interpretation for the gas.

  18. Cogeneration with gas turbine associated to the absorption refrigeration system: a computer program for exergy economics analysis; Cogeracao com turbina a gas associada ao sistema de refrigeracao por absorcao: um programa computacional para analise exergoeconomica

    Energy Technology Data Exchange (ETDEWEB)

    Antunes, Julio Santana [UNESP, Guaratingueta, SP (Brazil). Faculdade de Engenharia. Dept. de Matematica] E-mail: santana@feg.unesp.br; Silveira, Jose Luz; Balestieri, Jose Antonio Perrella [UNESP, Guaratingueta, SP (Brazil). Faculdade de Engenharia. Dept. de Energia

    2000-07-01

    This paper presents the development of a computer program for exergy and economic analysis of cogeneration systems applying gas turbine associated to the absorption refrigeration system. The computer program selects gas turbine systems viewing the operation under thermal parity through a data base composed by gas turbines commercially available in the market, under the ISO (International Standard Organization). The computer program corrects the system performance parameters selected for the installation local conditions. The exergy and economic analysis are made based on the lowest exergy manufacturing cost where the best system is considered. A case study of the computer program application is presented.

  19. Determination of mercury by multisyringe flow injection system with cold-vapor atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Leal, L.O.; Elsholz, O.; Forteza, R.; Cerda, V.

    2006-01-01

    A new software-controlled time-based multisyringe flow injection system for mercury determination by cold-vapor atomic absorption spectrometry is proposed. Precise known volumes of sample, reducing agent (1.1% SnCl 2 in 3% HCl) and carrier (3% HCl) are dispensed into a gas-liquid separation cell with a multisyringe burette coupled with one three-way solenoid valve. An argon flow delivers the reduced mercury to the spectrometer. The optimization of the system was carried out testing reaction coils and gas-liquid separators of different design as well as changing parameters, such as sample and reagents volumes, reagent concentrations and carrier gas flow rate, among others. The analytical curves were obtained within the range 50-5000 ng L -1 . The detection limit (3σ b /S) achieved is 5 ng L -1 . The relative standard deviation (R.S.D.) was 1.4%, evaluated from 16 successive injections of 250 ng L -1 Hg standard solution. The injection and sample throughput per hour were 44 and 11, respectively. This technique was validated by means of solid and water reference materials with good agreement with the certified values and was successfully applied to fish samples

  20. Simulator for design absorption refrigeration system; Simulador para projeto de ciclos de refrigeracao por absorcao

    Energy Technology Data Exchange (ETDEWEB)

    Morejon, C.F.M.; Brum, N. de C. [Universidade Federal, Rio de Janeiro, RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia. Programa de Engenharia Mecanica]. E-mails: Camilo_freddy@hotmail.com; Nisio@serv.com.ufrj.br

    2000-07-01

    This work presents a development of a thermal fluid dynamics model and a solution of a steady state absorption refrigeration cycle, with ammonia water as the working fluid. Analytical thermodynamics models expressing the enthalpy in function of pressure, temperature and composition (h=f(P,T,x)), are used with the aim to design all of the cycle devices, moved by any type of energy such as solar, natural gas, steam or electrical energy (Morejon and Hackenberg, 1978). The development of the analysis is carried out by the application of thermal fluid dynamics concepts together with a detailed study of the heat and mass transfer in the different cycle stages. The thermodynamic cycle model, obtained from equation of state for ammonia - water mixtures (Ziegker and Trepp, 1984), is represented by the relation h - x (enthalpy-composition) for different pressures and temperatures. The obtained models are used to implement computational codes in MAPLE-V facilitating the design and simulation of refrigeration system. This study can be applied in the systems of air conditioning and refrigeration chambers design. (author)

  1. SADA: Ecological Risk Based Decision Support System for Selective Remediation

    Science.gov (United States)

    Spatial Analysis and Decision Assistance (SADA) is freeware that implements terrestrial ecological risk assessment and yields a selective remediation design using its integral geographical information system, based on ecological and risk assessment inputs. Selective remediation ...

  2. Thermodynamic analysis of an absorption refrigeration system with ionic-liquid/refrigerant mixture as a working fluid

    International Nuclear Information System (INIS)

    Kim, Yoon Jo; Kim, Sarah; Joshi, Yogendra K.; Fedorov, Andrei G.; Kohl, Paul A.

    2012-01-01

    Thermodynamics of an ionic-liquid (IL) based absorption refrigeration system has been numerically analyzed. It provides an alternative to the normally toxic working fluids, such as the ammonia in conventional absorption systems. The use of ILs also eliminates crystallization and metal-compatibility problems of the water/LiBr system. Mixtures of refrigerants and imidazolium-based ILs are theoretically explored as the working fluid pairs in a miniature absorption refrigeration system, so as to utilize waste-heat to power a refrigeration/heat pump system for electronics cooling. A non-random two-liquid (NRTL) model was built and used to predict the solubility of the mixtures. Saturation temperatures at the evaporator and condenser were set at 25 °C and 50 °C, respectively, with the power dissipation of 100 W. Water in combination with [emim][BF 4 ] (1-ethyl-3-methylimidazolium tetrafluoroborate) gave the highest coefficient of performance (COP) around 0.9. The refrigerant/IL compatibility indicated by the circulation ratio, alkyl chain length of the IL, and thermodynamic properties of the refrigerants, such as latent heat of evaporation were proven to be important factors in determining the performance of the absorption system. The negative effect of high viscosity was mitigated by dilution of the IL with the refrigerant and the use of slightly larger microfluidic channel heat exchangers. -- Highlights: ► Mixtures of refrigerant/ionic-liquid are studied for absorption system. ► We carry out comprehensive theoretical thermodynamic analysis. ► The essential factors of refrigerant/IL affecting the performance are identified. ► Water/[emim][BF 4 ] showed the best performance of COP. ► The effects of high viscosity ILs on the system performance are not significant.

  3. New waste heat district heating system with combined heat and power based on absorption heat exchange cycle in China

    International Nuclear Information System (INIS)

    Sun Fangtian; Fu Lin; Zhang Shigang; Sun Jian

    2012-01-01

    A new waste heat district heating system with combined heat and power based on absorption heat exchange cycle (DHAC) was developed to increase the heating capacity of combined heat and power (CHP) through waste heat recovery, and enhance heat transmission capacity of the existing primary side district heating network through decreasing return water temperature by new type absorption heat exchanger (AHE). The DHAC system and a conventional district heating system based on CHP (CDH) were analyzed in terms of both thermodynamics and economics. Compared to CDH, the DHAC increased heating capacity by 31% and increased heat transmission capacity of the existing primary side district heating network by 75%. The results showed that the exergetic efficiency of DHAC was 10.41% higher and the product exergy monetary cost was 36.6¥/GJ less than a CHD. DHAC is an effective way to increase thermal utilization factor of CHP, and to reduce district heating cost. - Highlights: ► Absorption heat pumps are used to recover waste heat in CHP. ► Absorption heat exchanger can reduce exergy loss in the heat transfer process. ► New waste heat heating system (DHAC) can increase heating capacity of CHP by 31%. ► DHAC can enhance heat transmission capacity of the primary pipe network by 75%. ► DHAC system has the higher exergetic efficiency and the better economic benefit.

  4. The absorption and distribution of Cesium-134 in rice-soil system

    International Nuclear Information System (INIS)

    Xu Yinliang; Chen Chuanqun; Chen Bin; Sun Zhiming

    1991-01-01

    Dynamics of absorption of 134 Cs by rice shows that absorption rate is the fastest at boot stage; absorption capacities of 134 Cs in soils are different with the different physical-chemical properties of soils; absorption amounts vary with the time of irrigating 134 Cs; the closer the irrigation time to mature stage is, the more the absorption amount of 134 Cs in rice will be; the more the irrigating times are, and the higher the radioactivity of 134 Cs in irrigating water is, the more the absorption amount in rice will be. After brown rice is polished, contamination of 134 Cs can be decreased by 22.6-45.6%. The order of specific activity in rice is: bran > root > straw > husk > polished rice. Percentage activity of straw, brown rice, root and husk is 51.4%, 28.4%, 11.8% and 8.4% respectively. The migration of 134 Cs is very slow in soil and 95.1% of 134 Cs is concentrated in surface soil (0-2.5 cm). The distribution ratio of 134 Cs in the rice and soil is 6.1%:93.9%. Potassium ion can inhibit the absorption of 134 Cs by rice. There is an exponential function between the concentration of potassium ion and specific activity of 134 Cs in rice

  5. A Fast Adaptive Receive Antenna Selection Method in MIMO System

    Directory of Open Access Journals (Sweden)

    Chaowei Wang

    2013-01-01

    Full Text Available Antenna selection has been regarded as an effective method to acquire the diversity benefits of multiple antennas while potentially reduce hardware costs. This paper focuses on receive antenna selection. According to the proportion between the numbers of total receive antennas and selected antennas and the influence of each antenna on system capacity, we propose a fast adaptive antenna selection algorithm for wireless multiple-input multiple-output (MIMO systems. Mathematical analysis and numerical results show that our algorithm significantly reduces the computational complexity and memory requirement and achieves considerable system capacity gain compared with the optimal selection technique in the same time.

  6. Implementation of Computer Assisted Test Selection System in Local Governments

    Directory of Open Access Journals (Sweden)

    Abdul Azis Basri

    2016-05-01

    Full Text Available As an evaluative way of selection of civil servant system in all government areas, Computer Assisted Test selection system was started to apply in 2013. In phase of implementation for first time in all areas in 2014, this system selection had trouble in several areas, such as registration procedure and passing grade. The main objective of this essay was to describe implementation of new selection system for civil servants in the local governments and to seek level of effectiveness of this selection system. This essay used combination of study literature and field survey which data collection was made by interviews, observations, and documentations from various sources, and to analyze the collected data, this essay used reduction, display data and verification for made the conclusion. The result of this essay showed, despite there a few parts that be problem of this system such as in the registration phase but almost all phases of implementation of CAT selection system in local government areas can be said was working clearly likes in preparation, implementation and result processing phase. And also this system was fulfilled two of three criterias of effectiveness for selection system, they were accuracy and trusty. Therefore, this selection system can be said as an effective way to select new civil servant. As suggestion, local governments have to make prime preparation in all phases of test and make a good feedback as evaluation mechanism and together with central government to seek, fix and improve infrastructures as supporting tool and competency of local residents.

  7. Modulated Sine Waves for Differential Absorption Measurements Using a CW Laser System

    Science.gov (United States)

    Campbell, Joel F. (Inventor); Lin, Bing (Inventor); Nehrir, Amin R. (Inventor)

    2015-01-01

    A continuous wave Light Detection and Ranging (CW LiDAR) system utilizes two or more laser frequencies and time or range shifted pseudorandom noise (PN) codes to discriminate between the laser frequencies. The performance of these codes can be improved by subtracting out the bias before processing. The CW LiDAR system may be mounted to an artificial satellite orbiting the earth, and the relative strength of the return signal for each frequency can be utilized to determine the concentration of selected gases or other substances in the atmosphere.

  8. Materials and systems developments on solid absorption refrigeration with CaCl2·xNH3

    International Nuclear Information System (INIS)

    Iloeji, O.C.

    1995-10-01

    The paper presents some developments on the stabilization of CaCl 2 for use as a solid absorption material in refrigerators, the development of a refrigerator using the stabilized salt, and computer modelling of the refrigerator system. (author). 8 refs, 19 figs

  9. Comparison of vascular alpha(1)-adrenoceptor antagonism of tamsulosin in oral controlled absorption system (OCAS) and modified release (MR) formulations

    NARCIS (Netherlands)

    Michel, M. C.; Korstanje, C.; Krauwinkel, W.; Shear, M.; Davies, J.; Quartel, A.

    2005-01-01

    Objective: The cardiovascular a-l-adrenoceptor (AR) antagonism of the new oral controlled absorption system (OCAS) 0.4 mg tablet formulation of tamsulosin was compared with that of the modified release (MR) 0.4 mg capsule formulation in healthy male volunteers after a single dose in the fasted

  10. Comparison of the cardiovascular effects of tamsulosin oral controlled absorption system (OCAS) and alfuzosin prolonged release (XL)

    NARCIS (Netherlands)

    Michel, Martin C.; Chapple, Christopher R.

    2006-01-01

    OBJECTIVE: The cardiovascular (CV) effects of tamsulosin oral controlled absorption system (OCAS) 0.4 mg were compared with those of alfuzosin prolonged release (XL) 10 mg. METHODS: Two single-dose, crossover studies were performed. In study 1, CV alpha1-adrenoceptor antagonism was assessed by

  11. A comparison of neutron resonance absorption in thermal reactor lattices in the AUS neutronics code system with Monte Carlo calculations

    International Nuclear Information System (INIS)

    Robinson, G.S.

    1985-08-01

    The calculation of resonance shielding by the subgroup method, as incorporated in the MIRANDA module of the AUS neutronics code system, is compared with Monte Carlo calculatons for a number of thermal reactor lattices. For the large range of single rod and rod cluster lattices considered, AUS results for resonance absorption were high by up to two per cent

  12. Three-objective optimization of a novel triple-effect absorption heat transformer combined with a water desalination system

    International Nuclear Information System (INIS)

    Mahmoudi, S.M.S.; Salehi, S.; Yari, M.

    2017-01-01

    Highlights: • A new type of triple-effect absorption heat transformers is proposed. • A temperature lift of 180 °C is obtained by the proposed system. • The proposed system is observed to be the most effective. • The highest distilled water mass flow rate is obtained by the proposed system. - Abstract: A novel triple-effect absorption heat transformer is proposed and compared with a most studied configuration of triple-effect absorption heat transformer and a modified form of it from the viewpoint of exergoeconomics. All systems are integrated with water desalination system to produced distilled water. Sensitivity analyses are performed to identify the influence on the systems’ performance of such decision parameters as the temperatures of evaporator, condenser, absorber and absorbing evaporators for all the configurations. Then a three-objective optimization is accomplished to specify the optimal design points for the purpose of minimizing the product unit cost and maximizing the exergy coefficient of performance as well as the distilled water mass flow rate. In this regard, the Pareto frontiers are plotted for all the systems. The results show that, under the optimized conditions, the exergy coefficient of performance and distilled water mass flow rate for the proposed configuration can be higher by 16% and 38% with respect to the corresponding values in the other two systems. In addition, it is observed that the maximum gross temperature lift in the proposed system is about 20–40% higher than those in the other systems.

  13. Effluent Storage and Biomat Occurrence among Septic System Absorption Field Architectures in a Typic Fragiudult.

    Science.gov (United States)

    Prater, N J M; Brye, K R; Dunn, S; Soerens, T S; Sharpley, A N; Mason, E; Gbur, E E

    2013-07-01

    On-site wastewater treatment systems (OWTSs) are commonly used by households in areas of low population density to treat household wastewater and recycle it back to the environment. However, new absorption field products of differing architecture types have recently become available. A 3-yr field study was conducted in Bethel Heights, northwest Arkansas to assess several newer architecture types (i.e., chambers, polystyrene-aggregate, and gravel-less pipe) relative to the traditional pipe-and-gravel design under wet- and dry-soil conditions. Thirteen products of four different architecture types were installed in 46-cm-deep trenches in a Captina silt loam (fine-silty, siliceous, active, mesic Typic Fragiudult). Products were evaluated based on in-trench solution storage measured with an electronic water-level sensor approximately weekly from January 2009 through January 2012. Between May 2010 and January 2012, the thickness of any biomat formation was measured approximately weekly by insertion of a wooden dowel through in-trench monitoring ports. Architecture type alone did not affect ( > 0.05) in-trench solution storage. However, solution storage among individual products differed under wet- and dry-soil conditions ( storage but that several alternative products also had greater solution storage than that of the traditional pipe-and-gravel system. With no observed effluent surfacing, the soil morphology approach appears to be adequate and appropriately environmentally conservative for assigning typical single-family loading rates to alternative OWTS products and to the traditional pipe-and-gravel system. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  14. Hydrogeologic implications of increased septic-tank-soil-absorption system density, Ogden Valley, Weber County, Utah

    Science.gov (United States)

    Lowe, Mike; Miner, Michael L.; ,

    1990-01-01

    Ground water in Ogden Valley occurs in perched, confined, and unconfined aquifers in the valley fill to depths of 600 feet and more. The confined aquifer, which underlies only the western portion of the valley, is overlain by cleyey silt lacustrine sediments probably deposited during the Bonneville Basin's Little Valley lake cycle sometime between 90,000 and 150,000 years ago. The top of this cleyey silt confining layer is generally 25 to 60 feet below the ground surface. Unconfined conditions occur above and beyond the outer margin of the confining layer. The sediments overlying the confining layer are primarily Lake Bonneville deposits. Water samples from springs, streams, and wells around Pineview Reservoir, and from the reservoir itself, were collected and analyzed. These samples indicate that water quality in Ogden Valley is presently good. Average nitrate concentrations in the shallow unconfined aquifer increase toward the center of Ogden Valley. This trend was not observed in the confined aquifer. There is no evidence, however, of significant water-quality deterioration, even in the vicinity of Huntsville, a town that has been densely developed using septic-tank-soil-absorption systems for much of the time since it was founded in 1860.

  15. Resonant two-photon absorption and electromagnetically induced transparency in open ladder-type atomic system.

    Science.gov (United States)

    Moon, Han Seb; Noh, Heung-Ryoul

    2013-03-25

    We have experimentally and theoretically studied resonant two-photon absorption (TPA) and electromagnetically induced transparency (EIT) in the open ladder-type atomic system of the 5S(1/2) (F = 1)-5P(3/2) (F' = 0, 1, 2)-5D(5/2) (F″ = 1, 2, 3) transitions in (87)Rb atoms. As the coupling laser intensity was increased, the resonant TPA was transformed to EIT for the 5S(1/2) (F = 1)-5P(3/2) (F' = 2)-5D(5/2) (F″ = 3) transition. The transformation of resonant TPA into EIT was numerically calculated for various coupling laser intensities, considering all the degenerate magnetic sublevels of the 5S(1/2)-5P(3/2)-5D(5/2) transition. From the numerical results, the crossover from TPA to EIT could be understood by the decomposition of the spectrum into an EIT component owing to the pure two-photon coherence and a TPA component caused by the mixed term.

  16. Solar heating and cooling system with absorption chiller and low temperature latent heat storage: Energetic performance and operational experience

    Energy Technology Data Exchange (ETDEWEB)

    Helm, M.; Keil, C.; Hiebler, S.; Mehling, H.; Schweigler, C. [Bavarian Center for Applied Energy Research (ZAE Bayern) (Germany)

    2009-06-15

    Absorption cooling systems based on water/lithium bromide (LiBr) solution typically require an open wet cooling tower to transfer the reject heat to the ambient. Yet, water consumption, the need for water make-up and cleaning, formation of fog, and the risk of Legionella bacteria growth are hindering factors for the implementation of small solar cooling systems. The application of a latent heat storage supporting the heat rejection of the absorption chiller in conjunction with a dry cooling system allows eliminating the wet cooling tower. By that means heat rejection of the chiller is shifted to periods with lower ambient temperatures, i.e. night time or off-peak hours. The system concept and the hydraulic scheme together with an analysis of the energetic performance of the system are presented, followed by a report on the operation of a first pilot installation. (author)

  17. Evaluation of an oral carrier system in rats: bioavailability and gastrointestinal absorption properties of curcumin encapsulated PBCA nanoparticles

    International Nuclear Information System (INIS)

    Sun Min; Zhao Lixia; Guo Chenyu; Cao Fengliang; Chen Huanlei; Zhao Liyan; Tan Qi; Zhu Xiuqing; Zhu Fanping; Ding Tingting; Zhai Yingjie; Zhai Guangxi

    2012-01-01

    A new oral delivery system, polybutylcyanoacrylate nanoparticles (PBCNs), was introduced to improve the oral bioavailability of curcumin (CUR), a poorly soluble drug. The formulation was optimized by orthogonal design and the optimal PBCNs loading CUR exhibited a spherical shape under transmission electron microscopy with a range of 40–400 nm. Physicochemical state of CUR in PBCN was investigated by X-ray diffraction and the possible structure changes occurring in CUR after conjugating with polybutylcyanoacrylate were studied with FTIR. The results indicated that CUR in PBCN was in a non-crystalline state and CUR was encapsulated in PBCN without chemical reaction. The oral pharmacokinetic study was conducted in rats and the relative bioavailability of CUR encapsulated PBCNs to the crude CUR was more than 800%. The in situ absorption experiment in rat intestine indicated the absorption was first order with passive diffusion mechanism. The absorption results in various segments of intestine showed that the main absorption sites were ileum and colon. It can be concluded that PBCNs as an oral carrier can significantly improve the oral absorption of a poorly soluble drug.

  18. Evaluation of an oral carrier system in rats: bioavailability and gastrointestinal absorption properties of curcumin encapsulated PBCA nanoparticles

    Science.gov (United States)

    Sun, Min; Zhao, Lixia; Guo, Chenyu; Cao, Fengliang; Chen, Huanlei; Zhao, Liyan; Tan, Qi; Zhu, Xiuqing; Zhu, Fanping; Ding, Tingting; Zhai, Yingjie; Zhai, Guangxi

    2012-02-01

    A new oral delivery system, polybutylcyanoacrylate nanoparticles (PBCNs), was introduced to improve the oral bioavailability of curcumin (CUR), a poorly soluble drug. The formulation was optimized by orthogonal design and the optimal PBCNs loading CUR exhibited a spherical shape under transmission electron microscopy with a range of 40-400 nm. Physicochemical state of CUR in PBCN was investigated by X-ray diffraction and the possible structure changes occurring in CUR after conjugating with polybutylcyanoacrylate were studied with FTIR. The results indicated that CUR in PBCN was in a non-crystalline state and CUR was encapsulated in PBCN without chemical reaction. The oral pharmacokinetic study was conducted in rats and the relative bioavailability of CUR encapsulated PBCNs to the crude CUR was more than 800%. The in situ absorption experiment in rat intestine indicated the absorption was first order with passive diffusion mechanism. The absorption results in various segments of intestine showed that the main absorption sites were ileum and colon. It can be concluded that PBCNs as an oral carrier can significantly improve the oral absorption of a poorly soluble drug.

  19. Evaluation of an oral carrier system in rats: bioavailability and gastrointestinal absorption properties of curcumin encapsulated PBCA nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Sun Min; Zhao Lixia; Guo Chenyu; Cao Fengliang; Chen Huanlei; Zhao Liyan; Tan Qi; Zhu Xiuqing; Zhu Fanping; Ding Tingting; Zhai Yingjie; Zhai Guangxi, E-mail: professorzhai@yeah.net [Shandong University, Department of Pharmaceutics, College of Pharmacy (China)

    2012-02-15

    A new oral delivery system, polybutylcyanoacrylate nanoparticles (PBCNs), was introduced to improve the oral bioavailability of curcumin (CUR), a poorly soluble drug. The formulation was optimized by orthogonal design and the optimal PBCNs loading CUR exhibited a spherical shape under transmission electron microscopy with a range of 40-400 nm. Physicochemical state of CUR in PBCN was investigated by X-ray diffraction and the possible structure changes occurring in CUR after conjugating with polybutylcyanoacrylate were studied with FTIR. The results indicated that CUR in PBCN was in a non-crystalline state and CUR was encapsulated in PBCN without chemical reaction. The oral pharmacokinetic study was conducted in rats and the relative bioavailability of CUR encapsulated PBCNs to the crude CUR was more than 800%. The in situ absorption experiment in rat intestine indicated the absorption was first order with passive diffusion mechanism. The absorption results in various segments of intestine showed that the main absorption sites were ileum and colon. It can be concluded that PBCNs as an oral carrier can significantly improve the oral absorption of a poorly soluble drug.

  20. Study of absorption and re-emission processes in a ternary liquid scintillation system

    International Nuclear Information System (INIS)

    Xiao Hualin; Wang Naiyan; Li Xiaobo; Cao Jun; Wen Liangjian; Zheng Dong

    2010-01-01

    Liquid scintillators are widely used as the neutrino target in neutrino experiments. The absorption and emission of different components of a ternary liquid scintillator (Linear Alkyl Benzene (LAB) as the solvent, 2, 5-diphenyloxazole (PPO) as the fluor and p-bis-(o-methylstyryl)-benzene (bis-MSB) as wavelength shifter) are studied. It is shown that the absorption of this liquid scintillator is dominant by LAB and PPO at wavelengths less than 349 nm, and the absorption by bis-MSB becomes prevalent at the wavelength larger than 349 nm. The fluorescence quantum yields, which are the key parameters to model the absorption and re-emission processes in large liquid scintillation detectors, are measured. (authors)

  1. Microfluidic systems with ion-selective membranes.

    Science.gov (United States)

    Slouka, Zdenek; Senapati, Satyajyoti; Chang, Hsueh-Chia

    2014-01-01

    When integrated into microfluidic chips, ion-selective nanoporous polymer and solid-state membranes can be used for on-chip pumping, pH actuation, analyte concentration, molecular separation, reactive mixing, and molecular sensing. They offer numerous functionalities and are hence superior to paper-based devices for point-of-care biochips, with only slightly more investment in fabrication and material costs required. In this review, we first discuss the fundamentals of several nonequilibrium ion current phenomena associated with ion-selective membranes, many of them revealed by studies with fabricated single nanochannels/nanopores. We then focus on how the plethora of phenomena has been applied for transport, separation, concentration, and detection of biomolecules on biochips.

  2. Gas treating absorption theory and practice

    CERN Document Server

    Eimer, Dag

    2014-01-01

    Gas Treating: Absorption Theory and Practice provides an introduction to the treatment of natural gas, synthesis gas and flue gas, addressing why it is necessary and the challenges involved.  The book concentrates in particular on the absorption-desorption process and mass transfer coupled with chemical reaction. Following a general introduction to gas treatment, the chemistry of CO2, H2S and amine systems is described, and selected topics from physical chemistry with relevance to gas treating are presented. Thereafter the absorption process is discussed in detail, column hardware is explain

  3. Enabling the Distributed Generation Market of High Temperature Fuel Cell and Absorption Chiller Systems to Support Critical and Commercial Loads

    Science.gov (United States)

    DiMola, Ashley M.

    Buildings account for over 18% of the world's anthropogenic Greenhouse Gas (GHG) emissions. As a result, a technology that can offset GHG emissions associated with buildings has the potential to save over 9 Giga-tons of GHG emissions per year. High temperature fuel cell and absorption chiller (HTFC/AC) technology offers a relatively low-carbon option for meeting cooling and electric loads for buildings while producing almost no criteria pollutants. GHG emissions in the state of California would decrease by 7.48 million metric tons per year if every commercial building in the State used HTFC/AC technology to meet its power and cooling requirements. In order to realize the benefits of HTFC/AC technology on a wide scale, the distributed generation market needs to be exposed to the technology and informed of its economic viability and real-world potential. This work characterizes the economics associated with HTFC/AC technology using select scenarios that are representative of realistic applications. The financial impacts of various input factors are evaluated and the HTFC/AC simulations are compared to the economics of traditional building utilities. It is shown that, in addition to the emissions reductions derived from the systems, HTFC/AC technology is financially preferable in all of the scenarios evaluated. This work also presents the design of a showcase environment, centered on a beta-test application, that presents (1) system operating data gathered using a custom data acquisition module, and (2) HTFC/AC technology in a clear and approachable manner in order to serve the target audience of market stakeholders.

  4. Optimal design of solid oxide fuel cell, ammonia-water single effect absorption cycle and Rankine steam cycle hybrid system

    Science.gov (United States)

    Mehrpooya, Mehdi; Dehghani, Hossein; Ali Moosavian, S. M.

    2016-02-01

    A combined system containing solid oxide fuel cell-gas turbine power plant, Rankine steam cycle and ammonia-water absorption refrigeration system is introduced and analyzed. In this process, power, heat and cooling are produced. Energy and exergy analyses along with the economic factors are used to distinguish optimum operating point of the system. The developed electrochemical model of the fuel cell is validated with experimental results. Thermodynamic package and main parameters of the absorption refrigeration system are validated. The power output of the system is 500 kW. An optimization problem is defined in order to finding the optimal operating point. Decision variables are current density, temperature of the exhaust gases from the boiler, steam turbine pressure (high and medium), generator temperature and consumed cooling water. Results indicate that electrical efficiency of the combined system is 62.4% (LHV). Produced refrigeration (at -10 °C) and heat recovery are 101 kW and 22.1 kW respectively. Investment cost for the combined system (without absorption cycle) is about 2917 kW-1.

  5. Method for Business Process Management System Selection

    NARCIS (Netherlands)

    Thijs van de Westelaken; Bas Terwee; Pascal Ravesteijn

    2013-01-01

    In recent years business process management (BPM) and specifically information systems that support the analysis, design and execution of processes (also called business process management systems (BPMS)) are getting more attention. This has lead to an increase in research on BPM and BPMS. However

  6. Direct estimates of natural selection in Iberia indicate calcium absorption was not the only driver of lactase persistence in Europe.

    Science.gov (United States)

    Sverrisdóttir, Oddny Ósk; Timpson, Adrian; Toombs, Jamie; Lecoeur, Cecile; Froguel, Philippe; Carretero, Jose Miguel; Arsuaga Ferreras, Juan Luis; Götherström, Anders; Thomas, Mark G

    2014-04-01

    Lactase persistence (LP) is a genetically determined trait whereby the enzyme lactase is expressed throughout adult life. Lactase is necessary for the digestion of lactose--the main carbohydrate in milk--and its production is downregulated after the weaning period in most humans and all other mammals studied. Several sources of evidence indicate that LP has evolved independently, in different parts of the world over the last 10,000 years, and has been subject to strong natural selection in dairying populations. In Europeans, LP is strongly associated with, and probably caused by, a single C to T mutation 13,910 bp upstream of the lactase (LCT) gene (-13,910*T). Despite a considerable body of research, the reasons why LP should provide such a strong selective advantage remain poorly understood. In this study, we examine one of the most widely cited hypotheses for selection on LP--that fresh milk consumption supplemented the poor vitamin D and calcium status of northern Europe's early farmers (the calcium assimilation hypothesis). We do this by testing for natural selection on -13,910*T using ancient DNA data from the skeletal remains of eight late Neolithic Iberian individuals, whom we would not expect to have poor vitamin D and calcium status because of relatively high incident UVB light levels. None of the eight samples successfully typed in the study had the derived T-allele. In addition, we reanalyze published data from French Neolithic remains to both test for population continuity and further examine the evolution of LP in the region. Using simulations that accommodate genetic drift, natural selection, uncertainty in calibrated radiocarbon dates, and sampling error, we find that natural selection is still required to explain the observed increase in allele frequency. We conclude that the calcium assimilation hypothesis is insufficient to explain the spread of LP in Europe.

  7. Select PC/windows flat to develop data acquisition system

    International Nuclear Information System (INIS)

    Zhang Jin

    1993-01-01

    Through needing analysis, and also, considering user's ability of payment, the characteristic of China computer market, the computer developing tending, and the system's compatibility and up grade capability, PC/Windows flat are selected to develop a data acquisition system

  8. Selection of nuclear power information database management system

    International Nuclear Information System (INIS)

    Zhang Shuxin; Wu Jianlei

    1996-01-01

    In the condition of the present database technology, in order to build the Chinese nuclear power information database (NPIDB) in the nuclear industry system efficiently at a high starting point, an important task is to select a proper database management system (DBMS), which is the hinge of the matter to build the database successfully. Therefore, this article explains how to build a practical information database about nuclear power, the functions of different database management systems, the reason of selecting relation database management system (RDBMS), the principles of selecting RDBMS, the recommendation of ORACLE management system as the software to build database and so on

  9. Planar dynamical systems selected classical problems

    CERN Document Server

    Liu, Yirong; Huang, Wentao

    2014-01-01

    This book presents in an elementary way the recent significant developments in the qualitative theory of planar dynamical systems. The subjects are covered as follows: the studies of center and isochronous center problems, multiple Hopf bifurcations and local and global bifurcations of the equivariant planar vector fields which concern with Hilbert's 16th problem. This book is intended for graduate students, post-doctors and researchers in the area of theories and applications of dynamical systems. For all engineers who are interested the theory of dynamical systems, it is also a reasona

  10. Synthesis and selective IR absorption properties of iminodiacetic-acid intercalated MgAl-layered double hydroxide

    International Nuclear Information System (INIS)

    Wang Lijing; Xu Xiangyu; Evans, David G.; Duan Xue; Li Dianqing

    2010-01-01

    An MgAl-NO 3 -layered double hydroxide (LDH) precursor has been prepared by a method involving separate nucleation and aging steps (SNAS). Reaction with iminodiacetic acid (IDA) under weakly acidic conditions led to the replacement of the interlayer nitrate anions by iminodiacetic acid anions. The product was characterized by XRD, FT-IR, TG-DTA, ICP, elemental analysis and SEM. The results show that the original interlayer nitrate anions of LDHs precursor were replaced by iminodiacetic acid anions and that the resulting intercalation product MgAl-IDA-LDH has an ordered crystalline structure. MgAl-IDA-LDH was mixed with low density polyethylene (LDPE) using a masterbatch method. LDPE films filled with MgAl-IDA-LDH showed a higher mid to far infrared absorption than films filled with MgAl-CO 3 -LDH in the 7-25 μm range, particularly in the key 9-11 μm range required for application in agricultural plastic films. - Graphical abstract: Intercalation of iminodiacetic acid (IDA) anions in a MgAl-NO 3 -layered double hydroxide host leads to an enhancement of its infrared absorbing ability for application in agricultural plastic films.

  11. Multiuser hybrid switched-selection diversity systems

    KAUST Repository

    Shaqfeh, Mohammad; Alnuweiri, Hussein M.; Alouini, Mohamed-Slim

    2011-01-01

    system provides flexibility in trading-off the channel information feedback overhead with the prospected multiuser diversity gains. The users are clustered into groups, and the users' groups are ordered into a sequence. Per-group feedback thresholds

  12. ATTENTIONAL NETWORKS AND SELECTIVE VISUAL SYSTEM

    Directory of Open Access Journals (Sweden)

    ALEJANDRO CASTILLO MORENO

    2006-05-01

    Full Text Available In this paper we checked the principal researches and theories to explain the attention system functioning.We are going to start reviewing along time about the concept of attention, from filter theories andresources distributor theories, to the current theories in which attention is conceived as a control system.From this last point of view, we will emphasize on the attentional networks theory of Posner, thatproposes different systems to explain diverse aspects of attention, but they are related to each other. Atlast in this paper, we will mention experimental results that have been important to characterize theselective attentional mechanisms of the human visual system, using the attentional spotlight model forthis aim.

  13. Determining CDOM Absorption Spectra in Diverse Coastal Environments Using a Multiple Pathlength, Liquid Core Waveguide System. Measuring the Absorption of CDOM in the Field Using a Multiple Pathlength Liquid Waveguide System

    Science.gov (United States)

    Miller, Richard L.; Belz, Mathias; DelCastillo, Carlos; Trzaska, Rick

    2000-01-01

    We evaluated the accuracy, sensitivity and precision of a multiple pathlength, liquid core waveguide (MPLCW) system for measuring colored dissolved organic matter (CDOM) absorption in the UV-visible spectral range (370-700 nm). The MPLCW has four optical paths (2.0, 9.8, 49.3, and 204 cm) coupled to a single Teflon AF sample cell. Water samples were obtained from inland, coastal and ocean waters ranging in salinity from 0 to 36 PSU. Reference solutions for the MPLCW were made having a refractive index of the sample. CDOM absorption coefficients, a(sub CDOM), and the slope of the log-linearized absorption spectra, S, were compared with values obtained using a dual-beam spectrophotometer. Absorption of phenol red secondary standards measured by the MPLCW at 558 nm were highly correlated with spectrophotometer values (r > 0.99) and showed a linear response across all four pathlengths. Values of a(sub CDOM) measured using the MPLCW were virtually identical to spectrophotometer values over a wide range of concentrations. The dynamic range of a(sub CDOM) for MPLCW measurements was 0.002 - 231.5/m. At low CDOM concentrations (a(sub 370) CDOM) were slightly greater than MPLCW values and showed larger fluctuations at longer wavelengths due to limitations in instrument precision. In contrast, MPLCW spectra followed an exponential to 600 nm for all samples. The maximum deviation in replicate MPLCW spectra was less than 0.001 absorbance units. The portability, sampling, and optical characteristics of a MPLCW system provide significant enhancements for routine CDOM absorption measurements in a broad range of natural waters.

  14. Computerized adaptive testing item selection in computerized adaptive learning systems

    NARCIS (Netherlands)

    Eggen, Theodorus Johannes Hendrikus Maria; Eggen, T.J.H.M.; Veldkamp, B.P.

    2012-01-01

    Item selection methods traditionally developed for computerized adaptive testing (CAT) are explored for their usefulness in item-based computerized adaptive learning (CAL) systems. While in CAT Fisher information-based selection is optimal, for recovering learning populations in CAL systems item

  15. The system of employees motivation in a selected company

    OpenAIRE

    BEEROVÁ, Petra

    2014-01-01

    The system of employees motivation in a selected company is the title of this thesis that closely analyzes the system of employees motivation in a selected company and outlines some suggestions that could improve the management and performance in this area. Moreover, the focus is placed towards the motivation of employees in the workplace.

  16. X ray absorption fine structure of systems in the anharmonic limit

    Science.gov (United States)

    Mustredeleon, J.; Conradson, S. D.; Batistic, I.; Bishop, A. R.; Raistrick, I.; Jackson, W. E.; Brown, G. E.

    A new approach to the analysis of x-ray absorption fine structure (XAFS) data is presented. It is based on the use of radial distribution functions directly calculated from a single-particle ion Hamiltonian containing model potentials. The starting point of this approach is the statistical average of the XAFS for an atomic pair. This average can be computed using a radial distribution function (RDF), which can be expressed in terms of the eigenvalues and wavefunctions associated with the model potential. The pair potential describing the ionic motion is then expressed in terms of parameters that are determined by fitting this statistical average to the experimental XAFS spectrum. This approach allows the use of XAFS as a tool for mapping near-neighbor interatomic potentials, and allows the treatment of systems which exhibit strongly anharmonic potentials which can be treated by perturbative methods. Using this method we have analyzed the high temperature behavior of the oxygen contributions to the Fe K-edge XAFS in the ferrosilicate minerals andradite (Ca3Fe2Si3O12) and magnesiowustite (Mg(0.9)Fe(0.1)O). Using a temperature dependent anharmonic correction derived from these model compounds, we have found evidence for a local structural change in the Fe-O coordination environment upon melting of the geologically important mineral fayalite (Fe2SiO4). We have also employed this method to the study of the axial oxygen contributions to the polarized Cu K-edge XAFS on oriented samples of YBa2Cu3O7 and related compounds. From this study we find evidence for an axial oxygen-centered lattice distortion accompanying the superconducting phase transition and a correlation between this distortion and Tc. The relation of the observed lattice distortion to mechanisms of superconductivity is discussed.

  17. X-ray absorption fine structure of systems in the anharmonic limit

    International Nuclear Information System (INIS)

    Mustre de Leon, J.; Conradson, S.D.; Batistic, I.; Bishop, A.R.; Raistrick, I.; Jackson, W.E.; Brown, G.E.

    1991-01-01

    A new approach to the analysis of x-ray absorption fine structure (XAFS) data is presented. It is based on the use of radial distribution functions directly calculated from a single-particle ion hamiltonian containing model potentials. The starting point of this approach is the statistical average of the XAFS for an atomic pair. This average can be computed using a radial distribution function (RDF), which can be expressed in terms of the eigenvalues and wavefunctions associated with the model potential. The pair potential describing the ionic motion is then expressed in terms of parameters that are determined by fitting this statistical average to the experimental XAFS spectrum. This approach allow the use of XAFS as a tool for mapping near-neighbor interatomic potentials, and allows the treatment of systems which exhibit strongly anharmonic potentials which can be treated by perturbative methods. Using this method we have analyzed the high temperature behavior of the oxygen contributions to the Fe K-edge XAFS in the ferrosilicate minerals andradite (Ca 3 Fe 2 Si 3 O 12 ) and magnesiowustite (Mg 0.9 Fe 0.1 O). Using a temperature dependent anharmonic correction derived from these model compounds, we have found evidence for a local structural change in the Fe-O coordination environment upon melting of the geologically important mineral fayalite (Fe 2 SiO 4 ). We have also employed this method to the study of the axial oxygen contributions to the polarized Cu K-edge XAFS on oriented samples of YBa 2 Cu 3 O 7 and related compounds. From this study we find evidence for an axial oxygen-centered lattice distortion accompanying the superconducting phase transition and a correlation between this distortion and T c . The relation of the observed lattice distortion to mechanisms of superconductivity is discussed. 33 refs., 6 figs

  18. Titanium-based spectrally selective surfaces for solar thermal systems

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, A D; Holmes, J P

    1983-10-01

    A study of spectrally selective surfaces based on anodic oxide films on titanium is presented. These surfaces have low values of solar absorptance, 0.77, due to the nonideal optical properties of the anodic TiO2 for antireflection of titanium. A simple chemical etching process is described which gives a textured surface with dimensions similar to the wavelengths of solar radiation, leading to spectral selectivity. The performance of this dark-etched surface can be further improved by anodising, and optimum absorbers have been produced with alpha(s) 0.935 and hemispherical emittances (400 K) 0.23. The surface texturing effects a significant improvement in alpha(s) at oblique incidence.

  19. Effect of the hardener to epoxy monomer ratio on the water absorption behavior of the DGEBA/TETA epoxy system

    Directory of Open Access Journals (Sweden)

    Ayrton Alef Castanheira Pereira

    2016-02-01

    Full Text Available Abstract The water absorption behavior of the DGEBA/TETA epoxy system was evaluated as a function of the epoxy monomer to amine hardener ratio. Weight gain versus immersion time curves were obtained and the experimental points were fitted using Fickian and Non-Fickian diffusion models. The results obtained showed that for all epoxy monomer to hardener ratios analyzed water diffusion followed non-Fickian behavior. It was possible to correlate the water absorption behavior to the macromolecular structure developed when the epoxy/ hardener ratio was varied. All epoxy/hardener ratios present a two-phase macromolecular structure, composed of regions with high crosslink density and regions with lower crosslinking. Epoxy rich systems have a more open macromolecular structure with a lower fraction of the dense phase than the amine rich systems, which present a more compact two-phase structure.

  20. Measured performance of a 3 ton LiBr absorption water chiller and its effect on cooling system operation

    Science.gov (United States)

    Namkoong, D.

    1976-01-01

    A three ton lithium bromide absorption water chiller was tested for a number of conditions involving hot water input, chilled water, and the cooling water. The primary influences on chiller capacity were the hot water inlet temperature and the cooling water inlet temperature. One combination of these two parameters extended the output to as much as 125% of design capacity, but no combination could lower the capacity to below 60% of design. A cooling system was conceptually designed so that it could provide several modes of operation. Such flexibility is needed for any solar cooling system to be able to accommodate the varying solar energy collection and the varying building demand. It was concluded that a three-ton absorption water chiller with the kind of performance that was measured can be incorporated into a cooling system such as that proposed, to provide efficient cooling over the specified ranges of operating conditions.

  1. Measured performance of a 3-ton LiBr absorption water chiller and its effect on cooling system operation

    Science.gov (United States)

    Namkoong, D.

    1976-01-01

    A 3-ton lithium bromide absorption water chiller was tested for a number of conditions involving hot-water input, chilled water, and the cooling water. The primary influences on chiller capacity were the hot water inlet temperature and the cooling water inlet temperature. One combination of these two parameters extended the output to as much as 125% of design capacity, but no combination could lower the capacity to below 60% of design. A cooling system was conceptually designed so that it could provide several modes of operation. Such flexibility is needed for any solar cooling system to be able to accommodate the varying solar energy collection and the varying building demand. It is concluded that a 3-ton absorption water chiller with the kind of performance that was measured can be incorporated into a cooling system such as that proposed, to provide efficient cooling over the specified ranges of operating conditions.

  2. Analysis of hybrid membrane and chemical absorption systems for CO2 capture

    International Nuclear Information System (INIS)

    Binns, Michael; Oh, Se-Young; Kwak, Dong-Hun; Kim, Jin-Kuk

    2015-01-01

    Amine-based absorption of CO 2 is currently the industry standard technology for capturing CO 2 emitted from power plants, refineries and other large chemical plants. However, more recently there have been a number of competing technologies under consideration, including the use of membranes for CO 2 separation and purification. We constructed and analyzed two different hybrid configurations combining and connecting chemical absorption with membrane separation. For a particular flue gas which is currently treated with amine-based chemical absorption at a pilot plant we considered and tested how membranes could be integrated to improve the performance of the CO 2 capture. In particular we looked at the CO 2 removal efficiency and the energy requirements. Sensitivity analysis was performed varying the size of the membranes and the solvent flow rate

  3. Selected methods of rehabilitation in systemic sclerosis

    Directory of Open Access Journals (Sweden)

    Agnieszka Gerkowicz

    2017-09-01

    Full Text Available Systemic sclerosis is a chronic connective tissue disease characterized by microvascular abnormalities, immune disturbances and progressive fibrosis of the skin and internal organs. Skin involvement may result in contractures, leading to marked loss of hand mobility, adversely affecting the performance of daily activities and decreasing the quality of life. Face involvement not only causes functional loss, but also lowers the self-esteem of patients. Increasing attention has recently been focused on the need to rehabilitate patients with systemic sclerosis in order to prevent the development of joint contractures and loss of mobility. The study presents a review of the current literature on rehabilitation possibilities in patients with systemic sclerosis, with a special focus on physiotherapy methods.

  4. NPP site selection: A systems engineering approach

    Energy Technology Data Exchange (ETDEWEB)

    Pwani, Henry; Kamanja, Florah; Zolkaffly, Zulfakar; Jung, J. C. [KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2012-10-15

    The necessity for improved decision making concerning the siting and licensing of major power facilities has been accelerated in the past decade by the increased environmental consciousness of the public and by the energy crisis. These problems are exceedingly complex due to their multiple objective nature, the many interest groups, the long range time horizons, and the inherent uncertainties of the potential impacts of any decision. Along with the relatively objective economic and engineering concerns, the more subjective factors involving safety, environmental, and social issues are crucial to the problem. The preferences of the general public, as consumers, the utility companies, as builders and operators of power plant facilities, and environmentalists and the government must be accounted for in analyzing power plant siting and licensing issues. We advocate for a systems engineering approach that articulates stake holder's requirements, expert judgements, and a systems decision making approach. The appropriateness and application of systems decision making process is illustrated in this paper.

  5. NPP site selection: A systems engineering approach

    International Nuclear Information System (INIS)

    Pwani, Henry; Kamanja, Florah; Zolkaffly, Zulfakar; Jung, J. C.

    2012-01-01

    The necessity for improved decision making concerning the siting and licensing of major power facilities has been accelerated in the past decade by the increased environmental consciousness of the public and by the energy crisis. These problems are exceedingly complex due to their multiple objective nature, the many interest groups, the long range time horizons, and the inherent uncertainties of the potential impacts of any decision. Along with the relatively objective economic and engineering concerns, the more subjective factors involving safety, environmental, and social issues are crucial to the problem. The preferences of the general public, as consumers, the utility companies, as builders and operators of power plant facilities, and environmentalists and the government must be accounted for in analyzing power plant siting and licensing issues. We advocate for a systems engineering approach that articulates stake holder's requirements, expert judgements, and a systems decision making approach. The appropriateness and application of systems decision making process is illustrated in this paper

  6. Solar hybrid cooling system for high-tech offices in subtropical climate - Radiant cooling by absorption refrigeration and desiccant dehumidification

    International Nuclear Information System (INIS)

    Fong, K.F.; Chow, T.T.; Lee, C.K.; Lin, Z.; Chan, L.S.

    2011-01-01

    Highlights: → A solar hybrid cooling system is proposed for high-tech offices in subtropical climate. → An integration of radiant cooling, absorption refrigeration and desiccant dehumidification. → Year-round cooling and energy performances were evaluated through dynamic simulation. → Its annual primary energy consumption was lower than conventional system up to 36.5%. → The passive chilled beams were more energy-efficient than the active chilled beams. - Abstract: A solar hybrid cooling design is proposed for high cooling load demand in hot and humid climate. For the typical building cooling load, the system can handle the zone cooling load (mainly sensible) by radiant cooling with the chilled water from absorption refrigeration, while the ventilation load (largely latent) by desiccant dehumidification. This hybrid system utilizes solar energy for driving the absorption chiller and regenerating the desiccant wheel. Since a high chilled water temperature generated from the absorption chiller is not effective to handle the required latent load, desiccant dehumidification is therefore involved. It is an integration of radiant cooling, absorption refrigeration and desiccant dehumidification, which are powered up by solar energy. In this study, the application potential of the solar hybrid cooling system was evaluated for the high-tech offices in the subtropical climate through dynamic simulation. The high-tech offices are featured with relatively high internal sensible heat gains due to the intensive office electric equipment. The key performance indicators included the solar fraction and the primary energy consumption. Comparative study was also carried out for the solar hybrid cooling system using two common types of chilled ceilings, the passive chilled beams and active chilled beams. It was found that the solar hybrid cooling system was technically feasible for the applications of relatively higher cooling load demand. The annual primary energy

  7. Optimalization of selected RFID systems Parameters

    Directory of Open Access Journals (Sweden)

    Peter Vestenicky

    2004-01-01

    Full Text Available This paper describes procedure for maximization of RFID transponder read range. This is done by optimalization of magnetics field intensity at transponder place and by optimalization of antenna and transponder coils coupling factor. Results of this paper can be used for RFID with inductive loop, i.e. system working in near electromagnetic field.

  8. U(VI) complexation with selected flavonoids investigated by absorption and emission spectroscopy at light acidic conditions

    Energy Technology Data Exchange (ETDEWEB)

    Guenther, Alix; Geipel, Gerhard [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Biogeochemistry

    2017-06-01

    Flavonoids are secondary plant compounds and have important properties. Beside their antioxidant activity and effects as enzyme inhibitors, they can bind metals ions. The possible release of flavonoids from the root into the soil can affect the migration of radionuclides in the biological and geological environment. In this work, the complexation behavior of selected flavonols and a flavonol glycoside towards U(VI) were spectroscopically investigated and the corresponding complex stability constants were determined.

  9. U(VI) complexation with selected flavonoids investigated by absorption and emission spectroscopy at light acidic conditions

    International Nuclear Information System (INIS)

    Guenther, Alix; Geipel, Gerhard

    2017-01-01

    Flavonoids are secondary plant compounds and have important properties. Beside their antioxidant activity and effects as enzyme inhibitors, they can bind metals ions. The possible release of flavonoids from the root into the soil can affect the migration of radionuclides in the biological and geological environment. In this work, the complexation behavior of selected flavonols and a flavonol glycoside towards U(VI) were spectroscopically investigated and the corresponding complex stability constants were determined.

  10. Selection of Fuel System for Modern Heavy Duty Diesel Engines

    Directory of Open Access Journals (Sweden)

    G. M. Kukharonok

    2004-01-01

    Full Text Available Fuel systems of diesel engines have been analyzed. The paper shows components of the systems, peculiarities of their manufacturing process. Difference in efficiency of the systems, their application and market prospects are considered in the paper. While solving problems to design a power installation the essence of fuel system selection is given on the basis of an internal combustion engine.

  11. Mini-DIAL system measurements coupled with multivariate data analysis to identify TIC and TIM simulants: preliminary absorption database analysis

    International Nuclear Information System (INIS)

    Gaudio, P; Malizia, A; Gelfusa, M; Poggi, L.A.; Martinelli, E.; Di Natale, C.; Bellecci, C.

    2017-01-01

    Nowadays Toxic Industrial Components (TICs) and Toxic Industrial Materials (TIMs) are one of the most dangerous and diffuse vehicle of contamination in urban and industrial areas. The academic world together with the industrial and military one are working on innovative solutions to monitor the diffusion in atmosphere of such pollutants. In this phase the most common commercial sensors are based on “point detection” technology but it is clear that such instruments cannot satisfy the needs of the smart cities. The new challenge is developing stand-off systems to continuously monitor the atmosphere. Quantum Electronics and Plasma Physics (QEP) research group has a long experience in laser system development and has built two demonstrators based on DIAL (Differential Absorption of Light) technology could be able to identify chemical agents in atmosphere. In this work the authors will present one of those DIAL system, the miniaturized one, together with the preliminary results of an experimental campaign conducted on TICs and TIMs simulants in cell with aim of use the absorption database for the further atmospheric an analysis using the same DIAL system. The experimental results are analysed with standard multivariate data analysis technique as Principal Component Analysis (PCA) to develop a classification model aimed at identifying organic chemical compound in atmosphere. The preliminary results of absorption coefficients of some chemical compound are shown together pre PCA analysis. (paper)

  12. Layered surface structure of gas-atomized high Nb-containing TiAl powder and its impact on laser energy absorption for selective laser melting

    Science.gov (United States)

    Zhou, Y. H.; Lin, S. F.; Hou, Y. H.; Wang, D. W.; Zhou, P.; Han, P. L.; Li, Y. L.; Yan, M.

    2018-05-01

    Ti45Al8Nb alloy (in at.%) is designed to be an important high-temperature material. However, its fabrication through laser-based additive manufacturing is difficult to achieve. We present here that a good understanding of the surface structure of raw material (i.e. Ti45Al8Nb powder) is important for optimizing its process by selective laser melting (SLM). Detailed X-ray photoelectron spectroscopy (XPS) depth profiling and transmission electron microscopy (TEM) analyses were conducted to determine the surface structure of Ti45Al8Nb powder. An envelope structure (∼54.0 nm in thickness) was revealed for the powder, consisting of TiO2 + Nb2O5 (as the outer surface layer)/Al2O3 + Nb2O5 (as the intermediate layer)/Al2O3 (as the inner surface layer)/Ti45Al8Nb (as the matrix). During SLM, this layered surface structure interacted with the incident laser beam and improved the laser absorptivity of Ti45Al8Nb powder by ∼32.21%. SLM experiments demonstrate that the relative density of the as-printed parts can be realized to a high degree (∼98.70%), which confirms good laser energy absorption. Such layered surface structure with appropriate phase constitution is essential for promoting SLM of the Ti45Al8Nb alloy.

  13. Comparison and selection of off-grid PV systems

    Science.gov (United States)

    Izmailov, Andrey Yu.; Lobachevsky, Yakov P.; Shepovalova, Olga V.

    2018-05-01

    This work deals with comparison, evaluation and selection of PV systems of the same type based on their technical parameters either indicated in their technical specifications or calculated ones. Stand-alone and grid backed up photoelectric systems have been considered. General requirements for photoelectric system selection and evaluation have been presented that ensure system operability and required efficiency in operation conditions. Generic principles and definition of photoelectric systems characteristics have been considered. The described method is mainly targeted at PV engineering personnel and private customers purchasing PV systems. It can be also applied in the course of project contests, tenders, etc.

  14. Development of sound absorption measuring system with acoustic chamber; Kogata kyuon koka sokutei sochi no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Takahira, M.; Noba, M. [Toyota Motor Corp., Aichi (Japan); Matsuoka, H. [Nippon Soken, Inc., Tokyo (Japan)

    1998-05-01

    In order to measure sound absorption performance necessary to develop sound absorption materials, development was made on a device consisting of a small sound box capable of measurement inexpensively and easily, as a measure against the reverberation chamber method. In order to obtain stabilized diffusion sound internally, the sound box has a shape of asymmetric seven-side body in which sides do not face squarely with each other. The box was so sized that a large number of resonant vibration postures can be constituted at the targeted frequency simultaneously in the box. The box has a commercially available cone speaker with good acoustic output characteristics in frequency range of higher than 500 Hz installed on an inner side of the box. The sound source uses a method to derive sound absorption rate from difference of sound pressure levels. In order to eliminate need of averaging treatment by using a multi-point measurement inside the box, a discussion was given to provide an opening on part of the box to place the sound receiving point outside the opening. A square test piece is placed on the floor 0.5 meter or more away from the speaker in the box. As a result of the experiment, it was verified that the sound absorption rate obtained by this device corresponds well with that by the reverberation chamber method. The size of the test piece was also found adequate. 2 refs., 11 figs., 1 tab.

  15. High Pressure X-ray Absorption Studies on Correlated-Electron Systems

    International Nuclear Information System (INIS)

    Cornelius, Andrew L.

    2016-01-01

    This project used high pressure to alter the electron-electron and electron-lattice interactions in rare earth and actinide compounds. Knowledge of these properties is the starting points for a first-principles understanding of electronic and electronically related macroscopic properties. The research focused on a systematic study of x-ray absorption measurements on rare earth and actinide compounds.

  16. Low resolution spectroscopy of selected Algol systems

    Science.gov (United States)

    Devarapalli, Shanti Priya; Jagirdar, Rukmini; Parthasarathy, M.; Sahu, D. K.; Mohan, Vijay; Bhatt, B. C.; Thomas, Vineet S.

    2018-04-01

    The analysis of spectroscopic data for 30 Algol-type binaries is presented. All these systems are short period Algols having primaries with spectral types B and A. Dominant spectral lines were identified for the spectra collected and their equivalent widths were calculated. All the spectra were examined to understand presence of mass transfer, a disk or circumstellar matter and chromospheric emission. We also present first spectroscopic and period study for few Algols and conclude that high resolution spectra within and outside the primary minimum are needed for better understanding of these Algol type close binaries.

  17. Selective reduction of arsenic species by hydride generation - atomic absorption spectrometry. Part 2 - sample storage and arsenic determination in natural waters

    Directory of Open Access Journals (Sweden)

    Quináia Sueli P.

    2001-01-01

    Full Text Available Total arsenic, arsenite, arsinate and dimethylarsinic acid (DMA were selectively determined in natural waters by hydride generation - atomic absorption spectrometry, using sodium tetrahydroborate(III as reductant but in different reduction media. River water samples from the north region of Paraná State, Brazil, were analysed and showed arsenate as the principal arsenical form. Detection limits found for As(III (citrate buffer, As(III + DMA (acetic acid and As(III + As(V (hydrochloric acid were 0.6, 1.1 and 0.5 mg As L-1, respectively. Sample storage on the proper reaction media revealed to be a useful way to preserve the water sample.

  18. Development and operation of a real-time data acquisition system for the NASA-LaRC differential absorption lidar

    Science.gov (United States)

    Butler, C.

    1985-01-01

    Computer hardware and software of the NASA multipurpose differential absorption lidar (DIAL) sysatem were improved. The NASA DIAL system is undergoing development and experimental deployment for remote measurement of atmospheric trace gas concentration from ground and aircraft platforms. A viable DIAL system was developed with the capability of remotely measuring O3 and H2O concentrations from an aircraft platform. Test flights were successfully performed on board the NASA/Goddard Flight Center Electra aircraft from 1980 to 1984. Improvements on the DIAL data acquisition system (DAS) are described.

  19. Systemic absorption and adverse ocular and systemic effects after topical ophthalmic administration of 0.1% diclofenac to healthy cats.

    Science.gov (United States)

    Hsu, Kimberly K; Pinard, Chantale L; Johnson, Ron J; Allen, Dana G; KuKanich, Butch K; Nykamp, Stephanie G

    2015-03-01

    To quantify plasma concentrations and determine adverse ocular, renal, or hepatic effects associated with repeated topical ophthalmic application of 0.1% diclofenac to healthy cats. 8 healthy sexually intact male cats. A randomized, placebo-controlled crossover study was conducted. A topical formulation of 0.1% diclofenac was administered 4 times/d for 7 days to 4 cats, and artificial tear (control) solution was administered to the other 4 cats. After a 12-day washout period, cats received the other treatment. Ophthalmic examinations were performed daily. Plasma samples were obtained on days 1 and 7 for pharmacokinetic analysis. A CBC, serum biochemical analysis, urinalysis, determination of urine protein-to-creatinine ratio, and determination of glomerular filtration rate were performed before the start of the study and after each 7-day treatment period. Mild conjunctival hyperemia was the only adverse ocular effect detected. Maximal drug concentration and area under the curve were significantly higher on day 7 than on day 1. Diclofenac-treated cats had a significantly lower glomerular filtration rate than did control-treated cats after the second but not after the first treatment period, presumably associated with iatrogenic hypovolemia. Topical ophthalmic administration of 0.1% diclofenac was well tolerated in healthy cats, with only mild signs of ocular irritation. Detectable systemic concentrations of diclofenac were achieved with accumulation over 7 days. Systemic absorption of diclofenac may be associated with reduced glomerular filtration rate, particularly in volume-contracted animals. Topical ophthalmic 0.1% diclofenac should be used with caution in volume-contracted or systemically ill cats.

  20. Economy system and operation of a selected retail chain

    OpenAIRE

    KALUSOVÁ, Monika

    2011-01-01

    The goal of the thesis Economy system and operation of a selected retail chain is to explore and analyze the sphere in which the retailer chain operates, and evaluate their financial situation. At the same time, the selected retail chain will compare with the selected sectoral competition. The first part of thesis covers the theoretical information about issues, in particular the definition of basic terms of trade and retail. The second part of thesis includes application theoretical knowledg...

  1. Optimistic Selection Rule Better Than Majority Voting System

    Science.gov (United States)

    Sugiyama, Takuya; Obata, Takuya; Hoki, Kunihito; Ito, Takeshi

    A recently proposed ensemble approach to game-tree search has attracted a great deal of attention. The ensemble system consists of M computer players, where each player uses a different series of pseudo-random numbers. A combination of multiple players under the majority voting system would improve the performance of a Shogi-playing computer. We present a new strategy of move selection based on the search values of a number of players. The move decision is made by selecting one player from all M players. Each move is selected by referring to the evaluation value of the tree search of each player. The performance and mechanism of the strategy are examined. We show that the optimistic selection rule, which selects the player that yields the highest evaluation value, outperforms the majority voting system. By grouping 16 or more computer players straightforwardly, the winning rates of the strongest Shogi programs increase from 50 to 60% or even higher.

  2. Waste system optimization - can diameter selection

    International Nuclear Information System (INIS)

    Ashline, R.C.

    1983-08-01

    The purpose of the waste system optimization study is to define in terms of cost incentives the preferred waste package for HLW which has been converted to glass at a commercial reprocessing plant. The Waste Management Economic Model (WMEM) was employed to analyze the effect of varying important design parameters on the overall net present cost of waste handling. The parameters found to have the greatest effect on the calculated overall net present cost were can diameter, repository type (salt, basalt/bentonite, or welded tuff), allowable areal heat loading, and the repository availability date. The overall net present of a waste handling option is calculated over a 20-year operating period. It includes the total capital and operating costs associated with high-level and intermediate-level liquid waste storage, liquid waste solidification, hulls storage and compaction, and general process trash handling. It also includes the cask leasing and transportation costs associated with each waste type and the waste repository disposal costs. The waste repository disposal costs used in WMEM for this analysis were obtained from Battelle Pacific Northwest Laboratories and thir RECON model. 2 figures, 2 tables

  3. Selective tungsten deposition in a batch cold wall CVD system

    International Nuclear Information System (INIS)

    Chow, R.; Kang, S.; Harshbarger, W.R.; Susoeff, M.

    1987-01-01

    Selective deposition of tungsten offers many advantages for VLSI technology. The process can be used as a planarization technique for multilevel interconnect technology, it can be used to fill contacts and to provide a barrier layer between Al and Si materials, and the selective W process might be used as a self-aligned technology to provide low resistance layers on source/drain and gate conductors. Recent publications have indicate that cold wall CVD systems provide advantages for development of selective W process. Genus has investigated selective W deposition processing, and we have developed a selective W deposition process for the Genus 8402 multifilm deposition system. This paper describes the Genus 8402 system and the selective W process developed in this reactor. To further develop selective W technology, Genus has signed an agreement with General Electric establishing a joint development program. As a part of this program, the authors characterized the selective W process for encroachment, Si consumption and degrees of selectivity on various dielectrics. The status of this development activity and process characterization is reviewed in this paper

  4. ERP systems selection in multinational enterprises: a practical guide

    Directory of Open Access Journals (Sweden)

    Moutaz Haddara

    2018-01-01

    Full Text Available The Enterprise Resource Planning (ERP system selection is an early phase in the ERP adoption process. When organizations evaluate an ERP, they commonly develop their own selection criteria that usually involve various system and vendor related factors. While the selection process is critical, however, there is an apparent research gap in literature. The ERP selection effort also focuses on the system’s fit with the organizational requirements and needs. Thus, the selection phase is critical, because if an organization chooses an unfit ERP, the whole project could be predestined to fail. This research provides an overview of an ERP selection process at an overseas branch office of a multinational company. The process employed a simple multi-attribute rating technique (SMART for evaluation. In addition, this research presents how cross-border data protection laws between the parent company and its branch have influenced the selection process. As the ERP system has been implemented successfully, the method and the selection factors have been proven adequate for the selection process.

  5. ECMS--Educational Contest Management System for Selecting Elite Students

    Science.gov (United States)

    Schneider, Thorsten

    2004-01-01

    Selecting elite students out of a huge collective is a difficult task. The main problem is to provide automated processes to reduce human work. ECMS (Educational Contest Management System) is an online tool approach to help--fully or partly automated--with the task of selecting such elite students out of a mass of candidates. International tests…

  6. Polycyclic selection system for the tropical rainforests of northern Australia

    Science.gov (United States)

    Glen T. Dale; Grahame B. Applegate

    1992-01-01

    The polycyclic selection logging system developed and practiced for many years in the tropical rainforests of north Queensland has been successful in integrating timber production with the protection of conservation values. The system has been used by the Queensland Forest Service to manage north Queensland rainforests. The Queensland system has considerable potential...

  7. Sequence Selection and Performance in DS/CDMA Systems

    Directory of Open Access Journals (Sweden)

    Jefferson Santos Ambrosio

    2016-03-01

    Full Text Available In this work key concepts on coding division multiple access (CDMA communication systems have been discussed. The sequence selection impact on the performance and capacity of direct sequence CDMA (DS/CDMA systems under AWGN and increasing system loading, as well as under multiple antennas channels was investigated.

  8. Space Station Freedom regenerative water recovery system configuration selection

    Science.gov (United States)

    Reysa, R.; Edwards, J.

    1991-01-01

    The Space Station Freedom (SSF) must recover water from various waste water sources to reduce 90 day water resupply demands for a four/eight person crew. The water recovery system options considered are summarized together with system configuration merits and demerits, resource advantages and disadvantages, and water quality considerations used to select the SSF water recovery system.

  9. Matching People and Jobs: Value Systems and Employee Selection.

    Science.gov (United States)

    Heflich, Debra L.

    1981-01-01

    Offers strategies, based on six value systems, to reduce employee turnover. Maintains that understanding the value systems of people as they relate to jobs is the key to improving the selection process, and that employees should be chosen in accordance with how well their value systems match their work and work environments.

  10. Effective selection of transgenic papaya plants with the PMI/Man selection system.

    Science.gov (United States)

    Zhu, Yun J; Agbayani, Ricelle; McCafferty, Heather; Albert, Henrik H; Moore, Paul H

    2005-09-01

    The selectable marker gene phospho-mannose isomerase (pmi), which encodes the enzyme phospho-mannose isomerase (PMI) to enable selection of transformed cell lines on media containing mannose (Man), was evaluated for genetic transformation of papaya (Carica papaya L.). We found that papaya embryogenic calli have little or no PMI activity and cannot utilize Man as a carbon source; however, when calli were transformed with a pmi gene, the PMI activity was greatly increased and they could utilize Man as efficiently as sucrose. Plants regenerated from selected callus lines also exhibited PMI activity but at a lower specific activity level. Our transformation efficiency with Man selection was higher than that reported using antibiotic selection or with a visual marker. For papaya, the PMI/Man selection system for producing transgenic plants is a highly efficient addition to previously published methods for selection and may facilitate the stacking of multiple transgenes of interest. Additionally, since the PMI/Man selection system does not involve antibiotic or herbicide resistance genes, its use might reduce environmental concerns about the potential flow of those genes into related plant populations.

  11. Absorption heat pumps

    International Nuclear Information System (INIS)

    Formigoni, C.

    1998-01-01

    A brief description of the difference between a compression and an absorption heat pump is made, and the reasons why absorption systems have spread lately are given. Studies and projects recently started in the field of absorption heat pumps, as well as criteria usually followed in project development are described. An outline (performance targets, basic components) of a project on a water/air absorption heat pump, running on natural gas or LPG, is given. The project was developed by the Robur Group as an evolution of a water absorption refrigerator operating with a water/ammonia solution, which has been on the market for a long time and recently innovated. Finally, a list of the main energy and cost advantages deriving from the use of absorption heat pumps is made [it

  12. Contribution to analytical theory of neutron resonance absorption in heterogeneous reactor systems with cylindrical geometry

    International Nuclear Information System (INIS)

    Slipicevic, K.

    1968-12-01

    Following a review of the existing theories od resonance absorption this thesis includes a new approach for calculating the effective resonance integral of absorbed neutrons, new approximate formula for the penetration factor, an analysis of the effective resonance integral and the correction of the resonance integral taking into account the interference of potential and resonance dissipation. A separate chapter is devoted to calculation of the effective resonance integral for the regular reactor lattice with cylindrical fuel elements

  13. Förster resonance energy transfer, absorption and emission spectra in multichromophoric systems. III. Exact stochastic path integral evaluation.

    Science.gov (United States)

    Moix, Jeremy M; Ma, Jian; Cao, Jianshu

    2015-03-07

    A numerically exact path integral treatment of the absorption and emission spectra of open quantum systems is presented that requires only the straightforward solution of a stochastic differential equation. The approach converges rapidly enabling the calculation of spectra of large excitonic systems across the complete range of system parameters and for arbitrary bath spectral densities. With the numerically exact absorption and emission operators, one can also immediately compute energy transfer rates using the multi-chromophoric Förster resonant energy transfer formalism. Benchmark calculations on the emission spectra of two level systems are presented demonstrating the efficacy of the stochastic approach. This is followed by calculations of the energy transfer rates between two weakly coupled dimer systems as a function of temperature and system-bath coupling strength. It is shown that the recently developed hybrid cumulant expansion (see Paper II) is the only perturbative method capable of generating uniformly reliable energy transfer rates and emission spectra across a broad range of system parameters.

  14. Exergy and Exergoenvironmental Analysis of a CCHP System Based on a Parallel Flow Double-Effect Absorption Chiller

    Directory of Open Access Journals (Sweden)

    Ali Mousafarash

    2016-01-01

    Full Text Available A combined cooling, heating, and power (CCHP system which produces electricity, heating, and cooling is modeled and analyzed. This system is comprised of a gas turbine, a heat recovery steam generator, and a double-effect absorption chiller. Exergy analysis is conducted to address the magnitude and the location of irreversibilities. In order to enhance understanding, a comprehensive parametric study is performed to see the effect of some major design parameters on the system performance. These design parameters are compressor pressure ratio, gas turbine inlet temperature, gas turbine isentropic efficiency, compressor isentropic efficiency, and temperature of absorption chiller generator inlet. The results show that exergy efficiency of the CCHP system is higher than the power generation system and the cogeneration system. In addition, the results indicate that when waste heat is utilized in the heat recovery steam generator, the greenhouse gasses are reduced when the fixed power output is generated. According to the parametric study results, an increase in compressor pressure ratio shows that the network output first increases and then decreases. Furthermore, an increase in gas turbine inlet temperature increases the system exergy efficiency, decreasing the total exergy destruction rate consequently.

  15. Automation of cell-based drug absorption assays in 96-well format using permeable support systems.

    Science.gov (United States)

    Larson, Brad; Banks, Peter; Sherman, Hilary; Rothenberg, Mark

    2012-06-01

    Cell-based drug absorption assays, such as Caco-2 and MDCK-MDR1, are an essential component of lead compound ADME/Tox testing. The permeability and transport data they provide can determine whether a compound continues in the drug discovery process. Current methods typically incorporate 24-well microplates and are performed manually. Yet the need to generate absorption data earlier in the drug discovery process, on an increasing number of compounds, is driving the use of higher density plates. A simple, more efficient process that incorporates 96-well permeable supports and proper instrumentation in an automated process provides more reproducible data compared to manual methods. Here we demonstrate the ability to perform drug permeability and transport assays using Caco-2 or MDCKII-MDR1 cells. The assay procedure was automated in a 96-well format, including cell seeding, media and buffer exchanges, compound dispense, and sample removal using simple robotic instrumentation. Cell monolayer integrity was confirmed via transepithelial electrical resistance and Lucifer yellow measurements. Proper cell function was validated by analyzing apical-to-basolateral and basolateral-to-apical movement of rhodamine 123, a known P-glycoprotein substrate. Apparent permeability and efflux data demonstrate how the automated procedure provides a less variable method than manual processing, and delivers a more accurate assessment of a compound's absorption characteristics.

  16. Selective Attention in Multi-Chip Address-Event Systems

    Directory of Open Access Journals (Sweden)

    Giacomo Indiveri

    2009-06-01

    Full Text Available Selective attention is the strategy used by biological systems to cope with the inherent limits in their available computational resources, in order to efficiently process sensory information. The same strategy can be used in artificial systems that have to process vast amounts of sensory data with limited resources. In this paper we present a neuromorphic VLSI device, the “Selective Attention Chip” (SAC, which can be used to implement these models in multi-chip address-event systems. We also describe a real-time sensory-motor system, which integrates the SAC with a dynamic vision sensor and a robotic actuator. We present experimental results from each component in the system, and demonstrate how the complete system implements a real-time stimulus-driven selective attention model.

  17. Selective attention in multi-chip address-event systems.

    Science.gov (United States)

    Bartolozzi, Chiara; Indiveri, Giacomo

    2009-01-01

    Selective attention is the strategy used by biological systems to cope with the inherent limits in their available computational resources, in order to efficiently process sensory information. The same strategy can be used in artificial systems that have to process vast amounts of sensory data with limited resources. In this paper we present a neuromorphic VLSI device, the "Selective Attention Chip" (SAC), which can be used to implement these models in multi-chip address-event systems. We also describe a real-time sensory-motor system, which integrates the SAC with a dynamic vision sensor and a robotic actuator. We present experimental results from each component in the system, and demonstrate how the complete system implements a real-time stimulus-driven selective attention model.

  18. Managing Selection for Electronic Resources: Kent State University Develops a New System to Automate Selection

    Science.gov (United States)

    Downey, Kay

    2012-01-01

    Kent State University has developed a centralized system that manages the communication and work related to the review and selection of commercially available electronic resources. It is an automated system that tracks the review process, provides selectors with price and trial information, and compiles reviewers' feedback about the resource. It…

  19. Fast Time-Dependent Density Functional Theory Calculations of the X-ray Absorption Spectroscopy of Large Systems.

    Science.gov (United States)

    Besley, Nicholas A

    2016-10-11

    The computational cost of calculations of K-edge X-ray absorption spectra using time-dependent density functional (TDDFT) within the Tamm-Dancoff approximation is significantly reduced through the introduction of a severe integral screening procedure that includes only integrals that involve the core s basis function of the absorbing atom(s) coupled with a reduced quality numerical quadrature for integrals associated with the exchange and correlation functionals. The memory required for the calculations is reduced through construction of the TDDFT matrix within the absorbing core orbitals excitation space and exploiting further truncation of the virtual orbital space. The resulting method, denoted fTDDFTs, leads to much faster calculations and makes the study of large systems tractable. The capability of the method is demonstrated through calculations of the X-ray absorption spectra at the carbon K-edge of chlorophyll a, C 60 and C 70 .

  20. Novel ion imprinted magnetic mesoporous silica for selective magnetic solid phase extraction of trace Cd followed by graphite furnace atomic absorption spectrometry detection

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Bingshan; He, Man; Chen, Beibei; Hu, Bin, E-mail: binhu@whu.edu.cn

    2015-05-01

    Determination of trace Cd in environmental, biological and food samples is of great significance to toxicological research and environmental pollution monitoring. While the direct determination of Cd in real-world samples is difficult due to its low concentration and the complex matrix. Herein, a novel Cd(II)-ion imprinted magnetic mesoporous silica (Cd(II)-II-MMS) was prepared and was employed as a selective magnetic solid-phase extraction (MSPE) material for extraction of trace Cd in real-world samples followed by graphite furnace atomic absorption spectrometry (GFAAS) detection. Under the optimized conditions, the detection limit of the proposed method was 6.1 ng L{sup −1} for Cd with the relative standard deviation (RSD) of 4.0% (c = 50 ng L{sup −1}, n = 7), and the enrichment factor was 50-fold. To validate the proposed method, Certified Reference Materials of GSBZ 50009–88 environmental water, ZK018-1 lyophilized human urine and NIES10-b rice flour were analyzed and the determined values were in a good agreement with the certified values. The proposed method exhibited a robust anti-interference ability due to the good selectivity of Cd(II)-II-MMS toward Cd(II). It was successfully employed for the determination of trace Cd(II) in environmental water, human urine and rice samples with recoveries of 89.3–116%, demonstrating that the proposed method has good application potential in real world samples with complex matrix. - Highlights: • Novel Cd(II)-II-MMS was prepared by surface imprinting combined with a sol–gel process. • Cd(II)-II-MMS has a high selectivity and adsorption capacity for Cd(II). • A sensitive and selective method of Cd(II)-IIMSPE-GFAAS was developed for trace cadmium analysis. • The method can be applied to determine trace Cd in various samples with complicated matrix.

  1. Novel ion imprinted magnetic mesoporous silica for selective magnetic solid phase extraction of trace Cd followed by graphite furnace atomic absorption spectrometry detection

    International Nuclear Information System (INIS)

    Zhao, Bingshan; He, Man; Chen, Beibei; Hu, Bin

    2015-01-01

    Determination of trace Cd in environmental, biological and food samples is of great significance to toxicological research and environmental pollution monitoring. While the direct determination of Cd in real-world samples is difficult due to its low concentration and the complex matrix. Herein, a novel Cd(II)-ion imprinted magnetic mesoporous silica (Cd(II)-II-MMS) was prepared and was employed as a selective magnetic solid-phase extraction (MSPE) material for extraction of trace Cd in real-world samples followed by graphite furnace atomic absorption spectrometry (GFAAS) detection. Under the optimized conditions, the detection limit of the proposed method was 6.1 ng L −1 for Cd with the relative standard deviation (RSD) of 4.0% (c = 50 ng L −1 , n = 7), and the enrichment factor was 50-fold. To validate the proposed method, Certified Reference Materials of GSBZ 50009–88 environmental water, ZK018-1 lyophilized human urine and NIES10-b rice flour were analyzed and the determined values were in a good agreement with the certified values. The proposed method exhibited a robust anti-interference ability due to the good selectivity of Cd(II)-II-MMS toward Cd(II). It was successfully employed for the determination of trace Cd(II) in environmental water, human urine and rice samples with recoveries of 89.3–116%, demonstrating that the proposed method has good application potential in real world samples with complex matrix. - Highlights: • Novel Cd(II)-II-MMS was prepared by surface imprinting combined with a sol–gel process. • Cd(II)-II-MMS has a high selectivity and adsorption capacity for Cd(II). • A sensitive and selective method of Cd(II)-IIMSPE-GFAAS was developed for trace cadmium analysis. • The method can be applied to determine trace Cd in various samples with complicated matrix

  2. Simulation of a combined heating, cooling and domestic hot water system based on ground source absorption heat pump

    International Nuclear Information System (INIS)

    Wu, Wei; You, Tian; Wang, Baolong; Shi, Wenxing; Li, Xianting

    2014-01-01

    Highlights: • A combined heating/cooling/DHW system based on GSAHP is proposed in cold regions. • The soil imbalance is effectively reduced and soil temperature can be kept stable. • 20% and 15% of condensation/absorption heat is recovered by GSAHP to produce DHW. • The combined system can improve the primary energy efficiency by 23.6% and 44.4%. - Abstract: The amount of energy used for heating and domestic hot water (DHW) is very high and will keep increasing. The conventional ground source electrical heat pump used in heating-dominated buildings has the problems of thermal imbalance, decrease of soil temperature, and deterioration of heating performance. Ground source absorption heat pump (GSAHP) is advantageous in both imbalance reduction and primary energy efficiency (PEE) improvement; however, the imbalance is still unacceptable in the warmer parts of cold regions. A combined heating/cooling/DHW (HCD) system based on GSAHP is proposed to overcome this problem. The GSAHPs using generator absorber heat exchange (GAX) and single-effect (SE) cycles are simulated to obtain the performance under various working conditions. Different HCD systems in Beijing and Shenyang are simulated comparatively in TRNSYS, based on which the thermal imbalance, soil temperature, heat recovery, and energy efficiency are analyzed. Results show that GSAHP–GAX–HCD is suitable for Beijing and GSAHP–SE–HCD is suitable for Shenyang. The imbalance ratio can be reduced to −14.8% in Beijing and to 6.0% in Shenyang with an annual soil temperature variation of only 0.5 °C and 0.1 °C. Furthermore, about 20% and 15% of the total condensation/absorption heat is recovered to produce DHW, and the PEE can reach 1.516 in Beijing and 1.163 in Shenyang. The combined HCD systems can achieve a PEE improvement of 23.6% and 44.4% compared with the normal heating/cooling systems

  3. Methylmercury determination using a hyphenated high performance liquid chromatography ultraviolet cold vapor multipath atomic absorption spectrometry system

    International Nuclear Information System (INIS)

    Campos, Reinaldo C.; Goncalves, Rodrigo A.; Brandao, Geisamanda P.; Azevedo, Marlo S.; Oliveira, Fabiana; Wasserman, Julio

    2009-01-01

    The present work investigates the use of a multipath cell atomic absorption mercury detector for mercury speciation analysis in a hyphenated high performance liquid chromatography assembly. The multipath absorption cell multiplies the optical path while energy losses are compensated by a very intense primary source. Zeeman-effect background correction compensates for non-specific absorption. For the separation step, the mobile phase consisted in a 0.010% m/v mercaptoethanol solution in 5% methanol (pH = 5), a C 18 column was used as stationary phase, and post column treatment was performed by UV irradiation (60 deg. C, 13 W). The eluate was then merged with 3 mol L -1 HCl, reduction was performed by a NaBH 4 solution, and the Hg vapor formed was separated at the gas-liquid separator and carried through a desiccant membrane to the detector. The detector was easily attached to the system, since an external gas flow to the gas-liquid separator was provided. A multivariate approach was used to optimize the procedure and peak area was used for measurement. Instrumental limits of detection of 0.05 μg L -1 were obtained for ionic (Hg 2+ ) and HgCH 3 + , for an injection volume of 200 μL. The multipath atomic absorption spectrometer proved to be a competitive mercury detector in hyphenated systems in relation to the most commonly used atomic fluorescence and inductively coupled plasma mass spectrometric detectors. Preliminary application studies were performed for the determination of methyl mercury in sediments.

  4. Methylmercury determination using a hyphenated high performance liquid chromatography ultraviolet cold vapor multipath atomic absorption spectrometry system

    Energy Technology Data Exchange (ETDEWEB)

    Campos, Reinaldo C. [Department of Chemistry, Pontifical Catholic University of Rio de Janeiro, Rua Marques de S Vicente 225, 22453-900 Rio de Janeiro (Brazil)], E-mail: rccampos@puc-rio.br; Goncalves, Rodrigo A.; Brandao, Geisamanda P.; Azevedo, Marlo S. [Department of Chemistry, Pontifical Catholic University of Rio de Janeiro, Rua Marques de S Vicente 225, 22453-900 Rio de Janeiro (Brazil); Oliveira, Fabiana; Wasserman, Julio [Institut of Geosciences, Fluminense Federal University, Av. Gal. Milton Tavares de Souza, s/n, 24.210-340, Niteroi, Rio de Janeiro (Brazil)

    2009-06-15

    The present work investigates the use of a multipath cell atomic absorption mercury detector for mercury speciation analysis in a hyphenated high performance liquid chromatography assembly. The multipath absorption cell multiplies the optical path while energy losses are compensated by a very intense primary source. Zeeman-effect background correction compensates for non-specific absorption. For the separation step, the mobile phase consisted in a 0.010% m/v mercaptoethanol solution in 5% methanol (pH = 5), a C{sub 18} column was used as stationary phase, and post column treatment was performed by UV irradiation (60 deg. C, 13 W). The eluate was then merged with 3 mol L{sup -1} HCl, reduction was performed by a NaBH{sub 4} solution, and the Hg vapor formed was separated at the gas-liquid separator and carried through a desiccant membrane to the detector. The detector was easily attached to the system, since an external gas flow to the gas-liquid separator was provided. A multivariate approach was used to optimize the procedure and peak area was used for measurement. Instrumental limits of detection of 0.05 {mu}g L{sup -1} were obtained for ionic (Hg{sup 2+}) and HgCH{sub 3}{sup +}, for an injection volume of 200 {mu}L. The multipath atomic absorption spectrometer proved to be a competitive mercury detector in hyphenated systems in relation to the most commonly used atomic fluorescence and inductively coupled plasma mass spectrometric detectors. Preliminary application studies were performed for the determination of methyl mercury in sedi0011men.

  5. Fate of chemicals in skin after dermal application: does the in vitro skin reservoir affect the estimate of systemic absorption?

    International Nuclear Information System (INIS)

    Yourick, Jeffrey J.; Koenig, Michael L.; Yourick, Debra L.; Bronaugh, Robert L.

    2004-01-01

    Recent international guidelines for the conduct of in vitro skin absorption studies put forward different approaches for addressing the status of chemicals remaining in the stratum corneum and epidermis/dermis at the end of a study. The present study investigated the fate of three chemicals [dihydroxyacetone (DHA), 7-(2H-naphtho[1,2-d]triazol-2-yl)-3-phenylcoumarin (7NTPC), and disperse blue 1 (DB1)] in an in vitro absorption study. In these studies, human and fuzzy rat skin penetration and absorption were determined over 24 or 72 h in flow-through diffusion cells. Skin penetration of these chemicals resulted in relatively low receptor fluid levels but high skin levels. For DHA, penetration studies found approximately 22% of the applied dose remaining in the skin (in both the stratum corneum and viable tissue) as a reservoir after 24 h. Little of the DHA that penetrates into skin is actually available to become systemically absorbed. 7NTPC remaining in the skin after 24 h was approximately 14.7% of the applied dose absorbed. Confocal laser cytometry studies with 7NTPC showed that it is present across skin in mainly the epidermis and dermis with intense fluorescence around hair. For DB1, penetration studies found approximately 10% (ethanol vehicle) and 3% (formulation vehicle) of the applied dose localized in mainly the stratum corneum after 24 h. An extended absorption study (72 h) revealed that little additional DB1 was absorbed into the receptor fluid. Skin levels should not be considered as absorbed material for DHA or DB1, while 7NTPC requires further investigation. These studies illustrate the importance of determining the fate of chemicals remaining in skin, which could significantly affect the estimates of systemically available material to be used in exposure estimates. We recommend that a more conclusive means to determine the fate of skin levels is to perform an extended study as conducted for DB1

  6. Optimal Parameter Selection of Power System Stabilizer using Genetic Algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Hyeng Hwan; Chung, Dong Il; Chung, Mun Kyu [Dong-AUniversity (Korea); Wang, Yong Peel [Canterbury Univeristy (New Zealand)

    1999-06-01

    In this paper, it is suggested that the selection method of optimal parameter of power system stabilizer (PSS) with robustness in low frequency oscillation for power system using real variable elitism genetic algorithm (RVEGA). The optimal parameters were selected in the case of power system stabilizer with one lead compensator, and two lead compensator. Also, the frequency responses characteristics of PSS, the system eigenvalues criterion and the dynamic characteristics were considered in the normal load and the heavy load, which proved usefulness of RVEGA compare with Yu's compensator design theory. (author). 20 refs., 15 figs., 8 tabs.

  7. Goal Selection for Embedded Systems with Oversubscribed Resources

    Science.gov (United States)

    Rabideau, Gregg; Chien, Steve; McLaren, David

    2010-01-01

    We describe an efficient, online goal selection algorithm and its use for selecting goals at runtime. Our focus is on the re-planning that must be performed in a timely manner on the embedded system where computational resources are limited. In particular, our algorithm generates near optimal solutions to problems with fully specified goal requests that oversubscribe available resources but have no temporal flexibility. By using a fast, incremental algorithm, goal selection can be postponed in a "just-in-time" fashion allowing requests to be changed or added at the last minute. This enables shorter response cycles and greater autonomy for the system under control.

  8. Application of the exergetic cost theory to the LiBr/H2O vapour absorption system

    International Nuclear Information System (INIS)

    Misra, R.D.; Sahoo, P.K.; Gupta, A.

    2002-01-01

    Optimization of thermal systems is generally based on thermodynamic analysis. However, the systems so optimized often are not viable due to economic constraints. The Theory of Exergetic Cost, a thermoeconomic optimization technique, combines the thermodynamic analysis with that of economic constraints to obtain an optimum configuration of a thermal system. In this paper, this technique is applied to optimize a LiBr/H 2 O vapour absorption refrigeration system run by pressurized hot water for air-conditioning applications. The mathematical and numerical techniques-based optimization of thermal systems is not always possible due to plant complexities. Hence, a simplified cost minimization methodology, based on 'Theory of Exergetic Cost', is applied to evaluate the economic costs of all the internal flows and products of the system under consideration. As shown in this paper, once these costs are determined, an approximately optimum design configuration can be obtained

  9. Work flow management systems. Selection of Platforms and tools

    International Nuclear Information System (INIS)

    Munoz Garcia, M.

    1997-01-01

    This paper addresses a formal procedure for selecting the Platform and tools necessary to implement a Work Flow system in a company's organisation. The proposed method is based on a preliminary study to ascertain the company's requirements; in other words, the tool is selected on the basis of the environment in which it is to be used, thus making it essential to know the frequency of use, the types of tasks to be executed, the complexity of work flow, etc. Once the preliminary study has been performed, the formal selection method does no differ greatly from that for selecting any other tool. The objective is to establish a series of weighted parameters so that each candidate configuration can be assessed and one finally selected. Lastly, the paper discusses some practical considerations which became evident during the selection of a work flow management tool for our own company. (Author)

  10. Polarization-selective three-photon absorption and subsequent photoluminescence in CsPbBr3 single crystal at room temperature

    Science.gov (United States)

    Clark, D. J.; Stoumpos, C. C.; Saouma, F. O.; Kanatzidis, M. G.; Jang, J. I.

    2016-05-01

    We report on highly polarization-selective three-photon absorption (3PA) in a Bridgman-grown single crystal of CsPbBr3 oriented along the (112) direction, which is an inorganic counterpart to emerging organic-inorganic hybrid halide perovskites for solar-cell and optoelectronic applications. The crystal exhibits strong photoluminescence (PL) at room temperature as a direct consequence of 3PA of fundamental radiation. Interestingly, 3PA disappears when the input polarization is parallel to the (-110 ) direction. This 3PA effect is strongest when orthogonal to (-110 ) and the corresponding 3PA coefficient was measured to be γ =0.14 ±0.03 cm3/GW2 under picosecond-pulse excitation at the fundamental wavelength of λ =1200 nm. The laser-induced damage threshold was also determined to be about 20 GW/cm2 at the same wavelength. Based on relative PL intensities upon λ tuning over the entire 3PA range (1100 -1700 nm), we determined the nonlinear optical dispersion of the 3PA coefficient for CsPbBr3, which is consistent with a theoretical prediction. Experimentally observed significant polarization dependence of γ was explained by relevant selection rules. The perovskite is potentially important for nonlinear optical applications owing to its highly efficient 3PA-induced PL response with a sharp on/off ratio by active polarization control.

  11. Selecting personnel to work on the interactive graphics system

    International Nuclear Information System (INIS)

    Norton, F.J.

    1979-01-01

    The paper established criteria for the selection of personnel to work on the interactive graphics system and mentions some of human behavioral patterns that are created by the implementation of graphic systems. Some of the social and educational problems associated with the interactive graphics system will be discussed. The project also provided for collecting objective data which would be useful in assessing the benefits of interactive graphics systems

  12. Selecting personnel to work on the interactive graphics system

    Energy Technology Data Exchange (ETDEWEB)

    Norton, F.J.

    1979-11-30

    The paper established criteria for the selection of personnel to work on the interactive graphics system and mentions some of human behavioral patterns that are created by the implementation of graphic systems. Some of the social and educational problems associated with the interactive graphics system will be discussed. The project also provided for collecting objective data which would be useful in assessing the benefits of interactive graphics systems.

  13. Analyzing Water's Optical Absorption

    Science.gov (United States)

    2002-01-01

    A cooperative agreement between World Precision Instruments (WPI), Inc., and Stennis Space Center has led the UltraPath(TM) device, which provides a more efficient method for analyzing the optical absorption of water samples at sea. UltraPath is a unique, high-performance absorbance spectrophotometer with user-selectable light path lengths. It is an ideal tool for any study requiring precise and highly sensitive spectroscopic determination of analytes, either in the laboratory or the field. As a low-cost, rugged, and portable system capable of high- sensitivity measurements in widely divergent waters, UltraPath will help scientists examine the role that coastal ocean environments play in the global carbon cycle. UltraPath(TM) is a trademark of World Precision Instruments, Inc. LWCC(TM) is a trademark of World Precision Instruments, Inc.

  14. Evaluation of a flue gas driven open absorption system for heat and water recovery from fossil fuel boilers

    International Nuclear Information System (INIS)

    Wang, Zhenying; Zhang, Xiaoyue; Li, Zhen

    2016-01-01

    Highlights: • Flue gas driven open absorption system that efficiently recovers total heat. • Efficient heat and water recovery for various kinds of fossil fuel boilers. • Heat and water recovery efficiencies increase with moisture content of flue gas. • Temperature requirements for district heat supply and domestic hot water were met. • Experimental system surpasses conventional condensing system in total heat recovery. - Abstract: This paper presents an open absorption system for total heat recovery from fossil fuel boilers using the high temperature flue gas as the regeneration heat source. In this system, liquid desiccant serves as the recycling medium, which absorbs waste heat and moisture contained in the low temperature flue gas in the packed tower and then regenerates in the regenerator by the high temperature flue gas. Water vapor generated in the regenerator gets condensed after releasing heat to the heating water system and the condensing water also gets recycled. The return water collects heat from the solution water heat exchanger, the flue gas water heat exchanger and the condenser respectively and is then used for district heating. Driven by the vapor pressure difference between high humidity flue gas and the liquid desiccant, the heat recovery efficiency of the system is not limited by the dew point of the flue gas, enabling a warmer water to be heated up than the conventional condensing boiler. The performance of this system was analyzed theoretically and experimentally and the results showed that the system operated well for both district heat supply and domestic hot water supply. The system efficiency increased with the moisture content of flue gas and the total heat recovery was about 8.5%, 17.2%, 21.2%, and 9.2% higher than the conventional condensing system in the case of coal fired boiler, fuel oil boiler, natural gas boiler, and coke oven gas boiler, respectively.

  15. Calcium absorption

    International Nuclear Information System (INIS)

    Carlmark, B.; Reizenstein, P.; Dudley, R.A.

    1976-01-01

    The methods most commonly used to measure the absorption and retention of orally administered calcium are reviewed. Nearly all make use of calcium radioisotopes. The magnitude of calcium absorption and retention depends upon the chemical form and amount of calcium administered, and the clinical and nutritional status of the subject; these influences are briefly surveyed. (author)

  16. Optical absorption studies on biodegradable PVA/PVP blend polymer electrolyte system

    Science.gov (United States)

    Basha, S. K. Shahenoor; Reddy, K. Veera Bhadra; Rao, M. C.

    2018-05-01

    Biodegradable blend polymer electrolytes of PVA/PVP with different wt% ratios of MgCl2.6H2O have been prepared using solution cast technique. Optical absorption studies were carried-out on to the prepared films at room temperature using JASCO V-670 Spectrophotometer in the wavelength region 200-600 nm. Due to the clusters between the vibrations of molecules a broad peak is obtained due to п-п* transition in the wavelength region 310-340 nm.

  17. The mechanism and properties of bio-photon emission and absorption in protein molecules in living systems

    Science.gov (United States)

    Pang, Xiao-feng

    2012-05-01

    The mechanism and properties of bio-photon emission and absorption in bio-tissues were studied using Pang's theory of bio-energy transport, in which the energy spectra of protein molecules are obtained from the discrete dynamic equation. From the energy spectra, it was determined that the protein molecules could both radiate and absorb bio-photons with wavelengths of energy level transitions of the excitons. These results were consistent with the experimental data; this consisted of infrared absorption data from collagen, bovine serum albumin, the protein-like molecule acetanilide, plasma, and a person's finger, and the laser-Raman spectra of acidity I-type collagen in the lungs of a mouse, and metabolically active Escherichia coli. We further elucidated the mechanism responsible for the non-thermal biological effects produced by the infrared light absorbed by the bio-tissues, using the above results. No temperature rise was observed; instead, the absorbed infrared light promoted the vibrations of amides as well the transport of the bio-energy from one place to other in the protein molecules, which changed their conformations. These experimental results, therefore, not only confirmed the validity of the mechanism of bio-photon emission, and the newly developed theory of bio-energy transport mentioned above, but also explained the mechanism and properties of the non-thermal biological effects produced by the absorption of infrared light by the living systems.

  18. Design and analysis of a waste gasification energy system with solid oxide fuel cells and absorption chillers

    DEFF Research Database (Denmark)

    Rokni, Masoud

    2018-01-01

    Energy saving is an open point in most European countries where energy policies are oriented to reduce the use of fossil fuels, greenhouses emissions and energy independence, and to increase the use of renewable energies. In the last several years, new technologies have been developed and some...... of them received subsidies to increase installation and reduce cost. This article presents a new sustainable trigeneration system (power, heat and cool) based on a solid oxide fuel cell (SOFC) system integrated with an absorption chiller for special applications such as hotels, resorts, hospitals, etc....... with a focus on plant design and performance. The proposal system is based on the idea of gasifying the municipal waste, producing syngas serving as fuel for the trigeneration system. Such advanced system when improved is thus self-sustainable without dependency on net grid, district heating and district...

  19. Absorption studies

    International Nuclear Information System (INIS)

    Ganatra, R.D.

    1992-01-01

    Absorption studies were once quite popular but hardly anyone does them these days. It is easier to estimate the blood level of the nutrient directly by radioimmunoassay (RIA). However, the information obtained by estimating the blood levels of the nutrients is not the same that can be obtained from the absorption studies. Absorption studies are primarily done to find out whether some of the essential nutrients are absorbed from the gut or not and if they are absorbed, to determine how much is being absorbed. In the advanced countries, these tests were mostly done to detect pernicious anaemia where vitamin B 12 is not absorbed because of the lack of the intrinsic factor in the stomach. In the tropical countries, ''malabsorption syndrome'' is quire common. In this condition, several nutrients like fat, folic acid and vitamin B 12 are not absorbed. It is possible to study absorption of these nutrients by radioisotopic absorption studies

  20. Measure Guideline: Selecting Ventilation Systems for Existing Homes

    Energy Technology Data Exchange (ETDEWEB)

    Aldrich, Robb [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-02-01

    This document addresses adding -or improving - mechanical ventilation systems to existing homes. The purpose of ventilation is to remove contaminants from homes, and this report discusses where, when, and how much ventilation is appropriate in a home, including some discussion of relevant codes and standards. Advantages, disadvantages, and approximate costs of various system types are presented along with general guidelines for implementing the systems in homes. CARB intends for this document to be useful to decision makers and contractors implementing ventilation systems in homes. Choosing the "best" system is not always straightforward; selecting a system involves balancing performance, efficiency, cost, required maintenance, and several other factors. It is the intent of this document to assist contractors in making more informed decisions when selecting systems. Ventilation is an integral part of a high-performance home. With more air-sealed envelopes, a mechanical means of removing contaminants is critical for indoor environmental quality and building durability.

  1. Infrared reflection absorption spectroscopy study of radiation-heterogeneous processes in the system of aluminum-hexane

    International Nuclear Information System (INIS)

    Gadzhieva, N.N.; Rimikhanova, A.N.; Garibov, A.A.

    2004-01-01

    Full text: Infrared reflection absorption spectroscopy (IRRAS) was applied to study the regularities of radiation conversion of hexane on the surface of aluminum. The research object was the thin polished aluminum plate by mark of AD-00 with reflection coefficient R=0.8†0.85 in infrared range λ=2.2†15 μ . As adsorbate unsaturated vapors of spectroscopy clear hexane were used. The absorption of hexane (C 2 H 14 ) was being studied manometric at pressures P=(0.1†1.0)·10 2 Pa , what corresponded to monolayer value of 1-10. The samples were irradiated with γ-quanta of 60 Co with D=1.03 Gy·s -1 doze rate. Infrared reflection spectrum when linear-polarized radiation fall on the sample under angle ψ=10 o was measured by spectrophotometer 'Specord 71 JR' in diapason of 4000-650cm -1 at the temperature by mean of special reflecting arrangements. Formation of molecular hydrogen (H 2 ) and other gaseous products of decomposition were controlled by chromotographical and infrared spectroscopical methods. The analysis of hexane infrared absorption spectra after radiation-stimulated adsorption on the surface of aluminum, points out the formation of H-bonded hydrocarbon complex ( ν∼2680cm -1 ) with much loosening of C-H bond (the molecular form of absorption) and the possibility of proceeding dissociative absorption with formation of metal-alkyls (ν∼2880, 2920, 2970 cm -1 ). Probability of the last mentioned process, which proceeds in the most defective centers, increases with increasing of γ-radiation doze. It was established that the radiation processes in hetero system Al-ads.C 6 H 14 accelerate the radiolysis of hexane. At all these the radiation decomposition of hexane in hetero system Al-ads.C 6 H 14 is accompanied by formation the surface hydrides (ν∼1700-2000 cm -1 ), acetylene (ν∼3200-3300 cm -1 ), ethylene (ν∼980 cm -1 ), and also gaseous products of molecular hydrogen decomposition (H 2 ) and hydrocarbons C 1 -C 5 (bands with maxima 770, 790

  2. Atomic absorption determination of ultratrace tellurium in rocks utilizing high sensitivity sampling systems

    International Nuclear Information System (INIS)

    Beaty, R.D.

    1973-01-01

    The sampling boat and the graphite furnace were shown to possess the required sensitivity to detect tellurium at ultratrace levels, in a variety of sample types, by atomic absorption. In the sampling boat approach, tellurium in sample solutions is chemically separated and concentrated by extraction into methyl isobutyl ketone before measurement. For samples exhibiting extraction interferences or excessively high background absorption, a preliminary separation of tellurium by coprecipitation with selenium is described. Using this technique, tellurium can be quantitatively detected down to 5 nanograms and linear response is observed to 100 nanograms. Relative standard deviations of better than 7 percent are achieved for 50 nanograms of tellurium. For samples that have a tellurium content below the detection limits of the sampling boat, the graphite furnace is used for atomization. By this method, as little as 0.07 nanograms of tellurium can be detected, and a precision of 1 percent relative standard deviation is achievable at the 5 nanogram level. A routinely applicable procedure was developed for determining tellurium in rocks, using the graphite furnace, after a hydrofluoric acid decomposition of the sample. Using this procedure, tellurium data were obtained on 20 different rocks, and the significance of this new information is discussed. (Diss. Abstr. Int., B)

  3. Plasmon-enhanced absorption in a metal nanoparticles and photosynthetic molecules hybrid system

    Science.gov (United States)

    Fan, Zhiyuan; Govorov, Alexander

    2010-03-01

    Photosystem I from cyanobacteria is one of nature's most efficient light harvesting complexes, converting light energy into electronic energy with a quantum yield of 100% and an energy yield about 58%. It is very attractive to the nanotechnology community because of its nanoscale dimensions and excellent optoelectronic properties. This protein has the potential to be utilized in devices such as solar cells, electric switches, photo-detectors, etc. However, there is one limiting factor for potential applications of a single monolayer of these photosynthetic proteins. One monolayer absorbs less than 1% of sunlight's energy, despite their excellent optoelectronic properties. Recently, experiments [1] have been conducted to enhance light absorption with the assistance of metal nanoparticles as artificial antenna for the photosystem I. Here, we present a theoretical description of the strong plasmon-assisted interactions between the metal nanoparticles and the optical dipoles of the reaction centers observed in the experiments. The resonance and off-resonance plasmon effects enhance the electromagnetic fields around the photosystem-I molecules and, in this way, lead to enhanced absorption. [4pt] [1] I. Carmeli, I. Lieberman, L. Kraversky, Zhiyuan Fan, A. O. Govorov, G. Markovich, and S. Richter, submitted.

  4. Critical coupling and coherent perfect absorption for ranges of energies due to a complex gain and loss symmetric system

    International Nuclear Information System (INIS)

    Hasan, Mohammad; Ghatak, Ananya; Mandal, Bhabani Prasad

    2014-01-01

    We consider a non-Hermitian medium with a gain and loss symmetric, exponentially damped potential distribution to demonstrate different scattering features analytically. The condition for critical coupling (CC) for unidirectional wave and coherent perfect absorption (CPA) for bidirectional waves are obtained analytically for this system. The energy points at which total absorption occurs are shown to be the spectral singular points for the time reversed system. The possible energies at which CC occurs for left and right incidence are different. We further obtain periodic intervals with increasing periodicity of energy for CC and CPA to occur in this system. -- Highlights: •Energy ranges for CC and CPA are obtained explicitly for complex WS potential. •Analytical conditions for CC and CPA for PT symmetric WS potential are obtained. •Conditions for left and right CC are shown to be different. •Conditions for CC and CPA are shown to be that of SS for the time reversed system. •Our model shows the great flexibility of frequencies for CC and CPA

  5. Cooling performance and energy saving of a compression-absorption refrigeration system driven by a gas engine

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Z.G.; Guo, K.H. [Sun Yat-Sen University, Guangzhou (China). Engineering School

    2006-07-01

    The prototype of combined vapour compression-absorption refrigeration system was set up, where a gas engine drove directly an open screw compressor in a vapour compression refrigeration chiller and waste heat from the gas engine was used to operate absorption refrigeration cycle. The experimental procedure and results showed that the combined refrigeration system was feasible. The cooling capacity of the prototype reached about 589 kW at the Chinese rated conditions of air conditioning (the inlet and outlet temperatures of chilled water are 12 and 7{sup o}C, the inlet and outlet temperatures of cooling water are 30 and 35{sup o}C, respectively). Primary energy rate (PER) and comparative primary energy saving were used to evaluate energy utilization efficiency of the combined refrigeration system. The calculated results showed that the PER of the prototype was about 1.81 and the prototype saved more than 25% of primary energy compared to a conventional electrically driven vapour compression refrigeration unit. Error analysis showed that the total error of the combined cooling system measurement was about 4.2% in this work. (author)

  6. Use of process steam in vapor absorption refrigeration system for cooling and heating applications: An exergy analysis

    Directory of Open Access Journals (Sweden)

    S. Anand

    2016-12-01

    Full Text Available The exponential increase in cost of conventional fuels shifts the interest toward the use of alternative as well waste energy sources for the operation of refrigeration and air-conditioning units. The present study therefore analyzes the performance of a process steam-operated vapor absorption system for cooling and heating applications using ammonia and water as working fluids based on first and second laws of thermodynamics. A mathematical model has been developed based on exergy analysis to investigate the performance of the system. The different performance parameters such as coefficient of performance (COP and exergetic efficiency of absorption system for cooling and heating applications are also calculated under different operating conditions. The results obtained show that cooling and heating COP along with second law efficiency (exergy efficiency increases with the heat source temperature at constant evaporator, condenser, and absorber temperature. Also, COP as well as exergy efficiency increases with an increase in the evaporator temperature at constant generator, condenser, and absorber temperature. The effect of ambient temperature on the exergetic efficiency for cooling and heating applications is also studied. The results obtained from the simulation studies can be used to optimize different components of the system so that the performance can be improved significantly.

  7. A comprehensive, multi-objective optimization of solar-powered absorption chiller systems for air-conditioning applications

    International Nuclear Information System (INIS)

    Shirazi, Ali; Taylor, Robert A.; Morrison, Graham L.; White, Stephen D.

    2017-01-01

    Highlights: • Multi-objective optimization of solar single/multi-effect absorption chillers was conducted. • Primary energy consumption and total annual cost were considered as the objectives. • Optimized designs of the alternative configurations were compared. • A detailed sensitivity analysis of the Pareto optimal solutions was investigated. - Abstract: Solar heating and cooling (SHC) systems are currently under rapid development and deployment due to their potential to reduce the use of fossil fuel resources and to alleviate greenhouse gas emissions in the building sector – a sector which is responsible for ∼40% of the world energy use. Absorption chiller technology (traditionally powered by natural gas in large buildings), can easily be retrofitted to run on solar energy. However, numerous non-intuitive design choices must be analyzed to achieve the best techno-economic performance of these systems. To date, there has been little research into the optimal configurations among the long list of potential solar-driven absorption chiller systems. To address this lack of knowledge, this paper presents a systematic simulation-based, multi-objective optimization of three common, commercially available lithium bromide-water absorption chillers – single-effect, double-effect and triple-effect – powered by evacuated tube collectors (ETCs), evacuated flat plate collectors (EFPCs), and concentrating parabolic trough collectors (PTCs), respectively. To the best of authors’ knowledge, this is the first study of its kind that compares the optimized designs of the most promising configurations of solar-assisted absorption chillers against a common set of energy, economic, and environmental metrics from a holistic perspective. A simulation model of these three configurations is developed using TRNSYS 17. A combined energy, economic, and environmental analysis of the modeled systems is conducted to calculate the primary energy use as well as the levelized total

  8. Fixed-wavelength H2O absorption spectroscopy system enhanced by an on-board external-cavity diode laser

    International Nuclear Information System (INIS)

    Brittelle, Mack S; Simms, Jean M; Sanders, Scott T; Gord, James R; Roy, Sukesh

    2016-01-01

    We describe a system designed to perform fixed-wavelength absorption spectroscopy of H 2 O vapor in practical combustion devices. The system includes seven wavelength-stabilized distributed feedback (WSDFB) lasers, each with a spectral accuracy of  ±1 MHz. An on-board external cavity diode laser (ECDL) that tunes 1320–1365 nm extends the capabilities of the system. Five system operation modes are described. In one mode, a sweep of the ECDL is used to monitor each WSDFB laser wavelength with an accuracy of  ±30 MHz. Demonstrations of fixed-wavelength thermometry at 10 kHz bandwidth in near-room-temperature gases are presented; one test reveals a temperature measurement error of ∼0.43%. (paper)

  9. Operator psychological selection system for nuclear power plant

    International Nuclear Information System (INIS)

    He Xuhong; Huang Xiangrui

    2004-01-01

    Based on a detailed job analysis of nuclear power plant operator including operation procedures analysis, interview with personnel familiar with operator job, and 9 events happened in the past in the plant involved operator error analysis, several operator work characteristics and performance influence factors are obtained. According to these specific characteristics and factors, referring to the psychological selection research results in the other related critical occupational fields, a full psychological selection system of nuclear power plant operator is forwarded in this paper, including 21 dimensions in 3 facets as general psychological ability, personality and psychological healthy. Practical measurement methods for the proposed selection dimensions are discussed in the end

  10. Performance analysis of solar air cooled double effect LiBr/H2O absorption cooling system in subtropical city

    International Nuclear Information System (INIS)

    Li, Zeyu; Ye, Xiangyang; Liu, Jinping

    2014-01-01

    Highlights: • The meteorological data during the working period of air conditioning was measured. • The suitable working range of collector temperature of system was gotten. • The characteristic of hourly and monthly total efficiency of system were obtained. • The yearly performance of system was calculated. - Abstract: Due to the absence of cooling tower and independent on water, the air cooled solar double effect LiBr/H 2 O absorption cooling system is more convenient to be used in commercial building and household use. The performance with collector temperature is an important field for such system. The paper mainly deals with the performance with collector temperature for the solar air cooled double effect LiBr/H 2 O absorption cooling system in subtropical city. The parameters of system are: aperture area of collector array is 27 m 2 , tilted angle of collector with respect to the horizontal plane is 20 toward to south evaporator temperature is 5 °C and the cooling capacity is 20 kW. The simulation is based on the meteorological data of monthly typical day which was summarized from a year round measured data. A corresponding parametric model was developed. The hourly and average performance with the collector temperature for monthly typical day was obtained and discussed. It was found that the suitable working range of inlet temperature of collector is 110–130 °C to improve performance and lower the risk of crystallization. The difference of hourly total efficiency in 9:00–16:00 is less, and the monthly total efficiency from May to October is approximate. The yearly performance of system including total efficiency, cooling capacity per area of collector and solar fraction was given. Furthermore, the effect of effectiveness of heat exchanger and pressure drop on total efficiency and solar fraction was studied and compared. The paper can serve as a preliminary investigation of solar air cooled double effect LiBr/H 2 O absorption cooling system in

  11. On the relationship between perceived importance of ERP systems selection characteristics and satisfaction with selected ERP systems in these characteristics

    DEFF Research Database (Denmark)

    Sudzina, Frantisek; Pucihar, Andreja; Lenart, Gregor

    2011-01-01

    of the relationship between the two. The paper focuses on the correlation between importance of ERP system selection criteria and the level of satisfaction with the chosen ERP systems in these characteristics. The research hypothesis is that there exists a correlation between the two. The analysis presented...

  12. A system to measure suprathermal electron distribution functions in toroidal plasmas by electron cyclotron wave absorption

    International Nuclear Information System (INIS)

    Boyd, D.A.; Skiff, F.; Gulick, S.

    1997-01-01

    A two-chord, four-beam suprathermal electron diagnostic has been installed on TdeV (B>1.5 T, R=0.86 m, a=0.25 m). Resonant absorption of extraordinary mode electron cyclotron waves is measured to deduce the chordal averaged suprathermal electron distribution function amplitude at the resonant momentum. Simultaneously counterpropagating beams permit good refractive loss cancellation. A nonlinear frequency sweep leads to a concentration of appropriately propagating power in a narrow range of time of flight, thus increasing the signal-to-noise ratio and facilitating the rejection of spurious reflections. Numerous measurements of electron distribution functions have been obtained during lower-hybrid current-drive experiments. copyright 1997 American Institute of Physics

  13. Performance of one and a half-effect absorption cooling cycle of H2O/LiBr system

    International Nuclear Information System (INIS)

    Wang Jianzhao; Zheng Danxing

    2009-01-01

    The performances of half-effect, single-effect and double-effect H 2 O/LiBr absorption cooling cycles were analyzed, and it was found that there is an obvious blank for generation temperature between the maximum generation temperature of the single-effect cycle and the minimum generation temperature of the double-effect cycle. It was proposed that the one and a half-effect (1.5-effect) cycle can fill up the blank perfectly. The state of the art in the 1.5-effect cycles was reviewed and analyzed, and two new configurations of 1.5-effect cycles were proposed. Three configurations of 1.5-effect cycles, which are suitable for H 2 O/LiBr as working fluids, were selected to be analyzed in detail. The 1.5-effect cycle shows the optimum performance at the foregoing blank of generation temperature. For example, under the conditions of evaporation temperature t E is 5 deg. C, and condensation temperature t C is 42 deg. C, and absorption temperature t A is 37 deg. C, the optimum range of generation temperature t G for the 1.5-effect cycle is from 110 deg. C to 140 deg. C. The coefficient of performance of the 1.5-effect cycle is about 1.0, which is more than 30% higher than that of the single-effect cycle at the same condition. The effects of the efficiency of solution heat exchanger, the generation temperature, the absorption temperature (or the condensation temperature) and the evaporation temperature on the performances of the three configurations of 1.5-effect cycle were analyzed. It was shown that the configuration II, which is composed with a high-temperature single-effect subcycle and a low-temperature half-effect subcycle, has the highest coefficient of performance and the best operational flexibility. Among the four parameters analyzed, the performances of 1.5-effect cycles are most sensitive to the change of absorption temperature (or condensation temperature), and then to the change of generation temperature.

  14. One-step displacement dispersive liquid-liquid microextraction coupled with graphite furnace atomic absorption spectrometry for the selective determination of methylmercury in environmental samples.

    Science.gov (United States)

    Liang, Pei; Kang, Caiyan; Mo, Yajun

    2016-01-01

    A novel method for the selective determination of methylmercury (MeHg) was developed by one-step displacement dispersive liquid-liquid microextraction (D-DLLME) coupled with graphite furnace atomic absorption spectrometry. In the proposed method, Cu(II) reacted with diethyldithiocarbamate (DDTC) to form Cu-DDTC complex, which was used as the chelating agent instead of DDTC for the dispersive liquid-liquid microextraction (DLLME) of MeHg. Because the stability of MeHg-DDTC is higher than that of Cu-DDTC, MeHg can displace Cu from the Cu-DDTC complex and be preconcentrated in a single DLLME procedure. MeHg could be extracted into the extraction solvent phase at pH 6 while Hg(II) remained in the sample solution. Potential interference from co-existing metal ions with lower DDTC complex stability was largely eliminated without the need of any masking reagent. Under the optimal conditions, the limit of detection of this method was 13.6ngL(-1) (as Hg), and an enhancement factor of 81 was achieved with a sample volume of 5.0mL. The proposed method was successfully applied for the determination of trace MeHg in some environmental samples with satisfactory results. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. A Fuzzy-MOORA approach for ERP system selection

    Directory of Open Access Journals (Sweden)

    Prasad Karande

    2012-07-01

    Full Text Available In today’s global and dynamic business environment, manufacturing organizations face the tremendous challenge of expanding markets and meeting the customer expectations. It compels them to lower total cost in the entire supply chain, shorten throughput time, reduce inventory, expand product choice, provide more reliable delivery dates and better customer service, improve quality, and efficiently coordinate demand, supply and production. In order to accomplish these objectives, the manufacturing organizations are turning to enterprise resource planning (ERP system, which is an enterprise-wide information system to interlace all the necessary business functions, such as product planning, purchasing, inventory control, sales, financial and human resources into a single system having a shared database. Thus to survive in the global competitive environment, implementation of a suitable ERP system is mandatory. However, selecting a wrong ERP system may adversely affect the manufacturing organization’s overall performance. Due to limitations in available resources, complexity of ERP systems and diversity of alternatives, it is often difficult for a manufacturing organization to select and install the most suitable ERP system. In this paper, two ERP system selection problems are solved using fuzzy multi-objective optimization on the basis of ratio analysis (MOORA method and it is observed that in both the cases, SAP is the best solution.

  16. Selective adsorption of ions in charged slit-systems

    Directory of Open Access Journals (Sweden)

    M.Valiskó

    2013-01-01

    Full Text Available We study the selective adsorption of various cations into a layered slit system using grand canonical Monte Carlo simulations. The slit system is formed by a series of negatively charged membranes. The electrolyte contains two kinds of cations with different sizes and valences modeled by charged hard spheres immersed in a continuum dielectric solvent. We present results for various cases depending on the combinations of the properties of the competing cations. We concentrate to the case when the divalent cations are larger than the monovalent cations. In this case, size and charge have counterbalancing effects, which results in interesting selectivity phenomena.

  17. Selective determination of inorganic cobalt in nutritional supplements by ultrasound-assisted temperature-controlled ionic liquid dispersive liquid phase microextraction and electrothermal atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Berton, Paula; Martinis, Estefanía M.; Martinez, Luis D.; Wuilloud, Rodolfo G.

    2012-01-01

    Highlights: ► Synergy of ultrasound energy and TILDLME technique for improved metal extraction. ► Highly selective determination of inorganic Co species at trace levels. ► Speciation analysis of Co in several nutritional supplements with highly complex matrices. ► Development of an environmentally friendly microextraction technique with minimal waste production and sample consumption. - Abstract: In the present work, a simple and rapid analytical method based on application of ionic liquids (ILs) for inorganic Co(II) species (iCo) microextraction in a variety of nutrient supplements was developed. Inorganic Co was initially chelated with 1-nitroso-2-naphtol (1N2N) reagent followed by a modern technique named ultrasound-assisted temperature-controlled ionic liquid dispersive liquid phase microextraction (USA-TILDLME). The extraction was performed with 1-hexyl-3-methylimidazolium hexafluorophosphate [C 6 mim][PF 6 ] with the aid of ultrasound to improve iCo recovery. Finally, the iCo-enriched IL phase was solubilized in methanol and directly injected into an electrothermal atomic absorption spectrometer (ETAAS). Several parameters that could influence iCo microextraction and detection were carefully studied. Since the main difficulty in these samples is caused by high concentrations of potential interfering ions, different approaches were evaluated to eliminate interferences. The limit of detection (LOD) was 5.4 ng L −1 , while the relative standard deviation (RSD) was 4.7% (at 0.5 μg L −1 Co level and n = 10), calculated from the peak height of absorbance signals. Selective microextraction of iCo species was achieved only by controlling the pH value during the procedure. The method was thus successfully applied for determination of iCo species in nutritional supplements.

  18. Selective detection of Fe and Mn species at mineral surfaces in weathered granite by conversion electron yield X-ray absorption fine structure

    International Nuclear Information System (INIS)

    Itai, Takaaki; Takahashi, Yoshio; Uruga, Tomoya; Tanida, Hajime; Iida, Atsuo

    2008-01-01

    A new method for the speciation of Fe and Mn at mineral surfaces is proposed using X-ray absorption fine structure in conversion electron yield mode (CEY-XAFS). This method generally reflects information on the species at the sub-μm scale from the particle surface due to the limited escape depth of the inelastic Auger electron. The surface sensitivity of this method was assessed by experiments on two samples of granite showing different degrees of weathering. The XANES spectra of the Fe-K and Mn-K edge clearly gave different information for CEY and fluorescence (FL) modes. These XANES spectra of Fe and Mn show a good fit upon application of least-squares fitting using ferrihydrite/MnO 2 and biotite as the end members. The XANES spectra collected by CEY mode provided more selective information on the secondary phases which are probably present at the mineral surfaces. In particular, CEY-XANES spectra of Mn indicated the presence of Mn oxide in unweathered granite despite a very small contribution of Mn oxide being indicated by FL-XANES and selective chemical-extraction analyses. Manganese oxide could not be detected by micro-beam XANES (beam size: 5 x 5 μm 2 ) in unweathered granite, suggesting that Mn oxide thinly and ubiquitously coats mineral surface at a sub-μm scale. This information is important, since Mn oxide can be the host for various trace elements. CEY-XAFS can prove to be a powerful tool as a highly sensitive surface speciation method. Combination of CEY and FL-XAFS will help identify minor phases that form at mineral surfaces, but identification of Fe and Mn oxides at mineral surfaces is critical to understand the migration of trace elements in water-rock interaction

  19. Selective detection of Fe and Mn species at mineral surfaces in weathered granite by conversion electron yield X-ray absorption fine structure

    Energy Technology Data Exchange (ETDEWEB)

    Itai, Takaaki [Department of Earth and Planetary Systems Science, Hiroshima University, Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526 (Japan)], E-mail: itai-epss@hiroshima-u.ac.jp; Takahashi, Yoshio [Department of Earth and Planetary Systems Science, Hiroshima University, Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526 (Japan); Uruga, Tomoya; Tanida, Hajime [Japan Synchrotron Radiation Research Institute, 1-1-1 Kouto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan); Iida, Atsuo [Photon Factory, National Laboratory for High Energy Physics, O-ho, Tsukuba, Ibaraki 305 (Japan)

    2008-09-15

    A new method for the speciation of Fe and Mn at mineral surfaces is proposed using X-ray absorption fine structure in conversion electron yield mode (CEY-XAFS). This method generally reflects information on the species at the sub-{mu}m scale from the particle surface due to the limited escape depth of the inelastic Auger electron. The surface sensitivity of this method was assessed by experiments on two samples of granite showing different degrees of weathering. The XANES spectra of the Fe-K and Mn-K edge clearly gave different information for CEY and fluorescence (FL) modes. These XANES spectra of Fe and Mn show a good fit upon application of least-squares fitting using ferrihydrite/MnO{sub 2} and biotite as the end members. The XANES spectra collected by CEY mode provided more selective information on the secondary phases which are probably present at the mineral surfaces. In particular, CEY-XANES spectra of Mn indicated the presence of Mn oxide in unweathered granite despite a very small contribution of Mn oxide being indicated by FL-XANES and selective chemical-extraction analyses. Manganese oxide could not be detected by micro-beam XANES (beam size: 5 x 5 {mu}m{sup 2}) in unweathered granite, suggesting that Mn oxide thinly and ubiquitously coats mineral surface at a sub-{mu}m scale. This information is important, since Mn oxide can be the host for various trace elements. CEY-XAFS can prove to be a powerful tool as a highly sensitive surface speciation method. Combination of CEY and FL-XAFS will help identify minor phases that form at mineral surfaces, but identification of Fe and Mn oxides at mineral surfaces is critical to understand the migration of trace elements in water-rock interaction.

  20. Selective determination of inorganic cobalt in nutritional supplements by ultrasound-assisted temperature-controlled ionic liquid dispersive liquid phase microextraction and electrothermal atomic absorption spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Berton, Paula; Martinis, Estefania M. [Analytical Chemistry Research and Development Group (QUIANID), (LISAMEN-CCT-CONICET-Mendoza), Av. Ruiz Leal S/N Parque General San Martin, M 5502 IRA Mendoza (Argentina); Martinez, Luis D. [INQUISAL-CONICET, Departamento de Quimica Analitica, Facultad de Quimica, Bioquimica y Farmacia, Universidad Nacional de San Luis, San Luis (Argentina); Wuilloud, Rodolfo G., E-mail: rwuilloud@mendoza-conicet.gob.ar [Analytical Chemistry Research and Development Group (QUIANID), (LISAMEN-CCT-CONICET-Mendoza), Av. Ruiz Leal S/N Parque General San Martin, M 5502 IRA Mendoza (Argentina); Instituto de Ciencias Basicas, Universidad Nacional de Cuyo, Mendoza (Argentina)

    2012-02-03

    Highlights: Black-Right-Pointing-Pointer Synergy of ultrasound energy and TILDLME technique for improved metal extraction. Black-Right-Pointing-Pointer Highly selective determination of inorganic Co species at trace levels. Black-Right-Pointing-Pointer Speciation analysis of Co in several nutritional supplements with highly complex matrices. Black-Right-Pointing-Pointer Development of an environmentally friendly microextraction technique with minimal waste production and sample consumption. - Abstract: In the present work, a simple and rapid analytical method based on application of ionic liquids (ILs) for inorganic Co(II) species (iCo) microextraction in a variety of nutrient supplements was developed. Inorganic Co was initially chelated with 1-nitroso-2-naphtol (1N2N) reagent followed by a modern technique named ultrasound-assisted temperature-controlled ionic liquid dispersive liquid phase microextraction (USA-TILDLME). The extraction was performed with 1-hexyl-3-methylimidazolium hexafluorophosphate [C{sub 6}mim][PF{sub 6}] with the aid of ultrasound to improve iCo recovery. Finally, the iCo-enriched IL phase was solubilized in methanol and directly injected into an electrothermal atomic absorption spectrometer (ETAAS). Several parameters that could influence iCo microextraction and detection were carefully studied. Since the main difficulty in these samples is caused by high concentrations of potential interfering ions, different approaches were evaluated to eliminate interferences. The limit of detection (LOD) was 5.4 ng L{sup -1}, while the relative standard deviation (RSD) was 4.7% (at 0.5 {mu}g L{sup -1} Co level and n = 10), calculated from the peak height of absorbance signals. Selective microextraction of iCo species was achieved only by controlling the pH value during the procedure. The method was thus successfully applied for determination of iCo species in nutritional supplements.

  1. Database system selection for marketing strategies support in information systems

    Directory of Open Access Journals (Sweden)

    František Dařena

    2007-01-01

    Full Text Available In today’s dynamically changing environment marketing has a significant role. Creating successful marketing strategies requires large amount of high quality information of various kinds and data types. A powerful database management system is a necessary condition for marketing strategies creation support. The paper briefly describes the field of marketing strategies and specifies the features that should be provided by database systems in connection with these strategies support. Major commercial (Oracle, DB2, MS SQL, Sybase and open-source (PostgreSQL, MySQL, Firebird databases are than examined from the point of view of accordance with these characteristics and their comparison in made. The results are useful for making the decision before acquisition of a database system during information system’s hardware architecture specification.

  2. X-ray absorption spectroscopy of diluted system by undulator photon source and multi-element solid-state detector

    CERN Document Server

    Tanida, H

    2001-01-01

    In order to measure the extended X-ray absorption fine structure (EXAFS) spectrum of an ultra-diluted system, an optics and detector control system for a synchrotron radiation beamline is developed. The undulator gap width is continuously tuned to obtain the maximum X-ray photon flux during the energy scan for the EXAFS measurement. A piezoelectric translator optimizes the parallelism of the double crystal in a monochromator at each measurement point to compensate for mechanical errors of the monochromator, resulting in a smooth and intense X-ray photon flux during the measurement. For a detection of a weak fluorescence signal from diluted samples, a 19-element solid-state detector and digital signal processor are used. A K-edge EXAFS spectrum of iron in a myoglobin aqueous solution with a concentration of 5.58 parts per million was obtained by this system.

  3. Selecting a Relational Database Management System for Library Automation Systems.

    Science.gov (United States)

    Shekhel, Alex; O'Brien, Mike

    1989-01-01

    Describes the evaluation of four relational database management systems (RDBMSs) (Informix Turbo, Oracle 6.0 TPS, Unify 2000 and Relational Technology's Ingres 5.0) to determine which is best suited for library automation. The evaluation criteria used to develop a benchmark specifically designed to test RDBMSs for libraries are discussed. (CLB)

  4. Selective maintenance of multi-state systems with structural dependence

    International Nuclear Information System (INIS)

    Dao, Cuong D.; Zuo, Ming J.

    2017-01-01

    This paper studies the selective maintenance problem for multi-state systems with structural dependence. Each component can be in one of multiple working levels and several maintenance actions are possible to a component in a maintenance break. The components structurally form multiple hierarchical levels and dependence groups. A directed graph is used to represent the precedence relations of components in the system. A selective maintenance optimization model is developed to maximize the system reliability in the next mission under time and cost constraints. A backward search algorithm is used to determine the assembly sequence for a selective maintenance scenario. The maintenance model helps maintenance managers in determining the best combination of maintenance activities to maximize the probability of successfully completing the next mission. Examples showing the use of the proposed method are presented. - Highlights: • A selective maintenance model for multi-state systems is proposed considering both economic and structural dependence. • Structural dependence is modeled as precedence relationship when disassembling components for maintenance. • Resources for disassembly and maintenance are evaluated using a backward search algorithm. • Maintenance strategies with and without structural dependence are analyzed. • Ignoring structural dependence may lead to over-estimation of system reliability.

  5. On design of absorption, regeneration and recovery system of low concentration hydrogen and tritium in He with titanium sponge

    International Nuclear Information System (INIS)

    Fukuhara, Masashi

    1978-01-01

    Design of a titanium sponge system to remove hydrogen from the helium coolant of high temperature gas-cooled reactors or fusion reactors is discussed in this paper. The data for the present purpose have been accumulated. The equilibrium relation of Ti-H 2 system was given by McQuillan. The present author of this paper obtained an absorption equilibrium diagram, and measurements were made for lower partial pressure than that of McQuillan's data. A breakthrough curve and an adsorption-desorption breakthrough curve of H 2 -Ti sponge system, and the regeneration characteristics of the Ti sponge were measured. As the results of experiments, it is said that tritium and hydrogen can be removed with a Ti sponge system. Examples of the design of a practical system are presented. A disposable system was designed for OGL-1 under the principle that the used Ti sponge is a solid radioactive waste. A regenerative system was designed as a system, in which solid radioactive wastes are not produced. An example of a recovery system is also presented. Discussion on the reason why the Ti-sponge has not been used is presented. (Kato, T.)

  6. Design of absorption, regeneration and recovery system of low concentration hydrogen and tritium in He with titanium sponge

    Energy Technology Data Exchange (ETDEWEB)

    Fukuhara, M [Kawasaki Heavy Industries Ltd., Kobe (Japan)

    1978-10-01

    Design of a titanium sponge system to remove hydrogen from the helium coolant of high temperature gas-cooled reactors or fusion reactors is discussed in this paper. The data for the present purpose have been accumulated. The equilibrium relation of Ti-H/sub 2/ system was given by McQuillan. The present author of this paper obtained an absorption equilibrium diagram, and measurements were made for lower partial pressure than that of McQuillan's data. A breakthrough curve and an adsorption-desorption breakthrough curve of H/sub 2/-Ti sponge system, and the regeneration characteristics of the Ti sponge were measured. As the results of experiments, it is said that tritium and hydrogen can be removed with a Ti sponge system. Examples of the design of a practical system are presented. A disposable system was designed for OGL-1 under the principle that the used Ti sponge is a solid radioactive waste. A regenerative system was designed as a system, in which solid radioactive wastes are not produced. An example of a recovery system is also presented. Discussion on the reason why the Ti-sponge has not been used is presented.

  7. SIMULATION OF SOLAR LITHIUM BROMIDE–WATER ABSORPTION COOLING SYSTEM WITH DOUBLE GLAZED FLAT PLATE COLLECTOR FOR ADRAR

    Directory of Open Access Journals (Sweden)

    ML CHOUGUI

    2014-12-01

    Full Text Available Adrar is a city in the Sahara desert, in southern Algeria known for its hot and dry climate, where a huge amount of energy is used for air conditioning. The aim of this research is to simulate a single effect lithium bromide–water absorption chiller coupled to a double-glazed flat plate collector to supply the cooling loads for a house of 200m2 in Adrar. The thermal energy is stored in an insulated thermal storage tank. The system was designed to cover a cooling load of 10.39KW for design day of July. Thermodynamic model was established to simulate the absorption cycle. The results have shown that the collector mass flow rate has a negligible effect on the minimum required collector area, but it has a significant effect on the optimum capacity of the storage tank. The minimum required collector area was about 65.3 m2, which could supply the cooling loads for the sunshine hours of the design day for July. The operation of the system has also been considered after sunset by saving solar energy.

  8. Neural mechanisms of selective attention in the somatosensory system.

    Science.gov (United States)

    Gomez-Ramirez, Manuel; Hysaj, Kristjana; Niebur, Ernst

    2016-09-01

    Selective attention allows organisms to extract behaviorally relevant information while ignoring distracting stimuli that compete for the limited resources of their central nervous systems. Attention is highly flexible, and it can be harnessed to select information based on sensory modality, within-modality feature(s), spatial location, object identity, and/or temporal properties. In this review, we discuss the body of work devoted to understanding mechanisms of selective attention in the somatosensory system. In particular, we describe the effects of attention on tactile behavior and corresponding neural activity in somatosensory cortex. Our focus is on neural mechanisms that select tactile stimuli based on their location on the body (somatotopic-based attention) or their sensory feature (feature-based attention). We highlight parallels between selection mechanisms in touch and other sensory systems and discuss several putative neural coding schemes employed by cortical populations to signal the behavioral relevance of sensory inputs. Specifically, we contrast the advantages and disadvantages of using a gain vs. spike-spike correlation code for representing attended sensory stimuli. We favor a neural network model of tactile attention that is composed of frontal, parietal, and subcortical areas that controls somatosensory cells encoding the relevant stimulus features to enable preferential processing throughout the somatosensory hierarchy. Our review is based on data from noninvasive electrophysiological and imaging data in humans as well as single-unit recordings in nonhuman primates. Copyright © 2016 the American Physiological Society.

  9. STRATEGY FOR EVALUATION AND SELECTION OF SYSTEMS FOR ELECTRONIC LEARNING

    Directory of Open Access Journals (Sweden)

    Dubravka Mandušić

    2012-12-01

    Full Text Available Today`s technology supported and accelerated learning time requires constant and continuous acquisition of new knowledge. On the other hand, it does not leave enough time for additional education. Increasing number of E-learning systems, withdraws a need for precise evaluation of functionality that those systems provide; so they could be reciprocally compared. While implementing new systems for electronic learning, it is very important to pre-evaluate existing systems in order to select the one that meets all defined parameters, with low costs/investment. Proper evaluation can save time and money.

  10. Configuration Selection for Reconfigurable Control of Piecewise Affine Systems

    DEFF Research Database (Denmark)

    Tabatabaeipour, Mojtaba; Gholami, M.; Bak, T.

    2015-01-01

    the recongurability of the system and the optimal conguration in the architecture design phase. A recongurable control must ensure stability of the recongured system and, if possible, a graceful degradation in the performance. Therefore, in the proposed recongurability analysis, we consider both stabilizability......In this paper, the problem of conguration selection i.e. sensor/actuator placement for piecewise ane (PWA) systems subject to both sensor and actuator faults is considered. A method is proposed that provides a tool for the design phase to decide about the optimal placement of sensor/actuators where...... and performance of the system. The efficiency of the proposed method is demonstrated on several numerical examples...

  11. Designing a fuzzy expert system for selecting knowledge management strategy

    Directory of Open Access Journals (Sweden)

    Ameneh Khadivar

    2014-12-01

    Full Text Available knowledge management strategy is mentioned as one of the most important success factors for implementing knowledge management. The KM strategy selection is a complex decision that requires consideration of several factors. For evaluation and selection of an appropriate knowledge management strategy in organizations, many factors must be considered. The identified factors and their impact on knowledge management strategy are inherently ambiguous. In this study, an overview of theoretical foundations of research regarding the different knowledge management strategies has been done And factors influencing the knowledge management strategy selection have been extracted from conceptual frameworks and models. How these factors influence the knowledge management strategy selection is extracted through the fuzzy Delphi. Next a fuzzy expert system for the selection of appropriate knowledge management strategy is designed with respect to factors that have an impact on knowledge management strategy. The factors which influence the selection of knowledge management strategy include: general business strategy, organizational structure, cultural factors, IT strategy, strategic human resource management, social level, the types of knowledge creation processes and release it. The factors which influence the knowledge management strategy selection include: business strategy general, organizational structure, cultural factors, IT strategy, human resource management strategies, socialization level, knowledge types and its creation and diffusion processes. According to identified factors which affect the knowledge management strategy, the final strategy is recommended based on the range of human-oriented and system-oriented by keep the balance of explicit and implicit knowledge. The Designed system performance is tested and evaluated by the information related to three Iranian organization.

  12. Measure Guideline: Selecting Ventilation Systems for Existing Homes

    Energy Technology Data Exchange (ETDEWEB)

    Aldrich, R. [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States)

    2014-02-01

    This report, developed by Building America research team CARB, addresses adding or improving mechanical ventilation systems to existing homes. The goal of this report is to assist decision makers and contractors in making informed decisions when selecting ventilation systems for homes. With more air-sealed envelopes, a mechanical means of removing contaminants is critical for indoor environmental quality and building durability. The purpose of ventilation is to remove contaminants from homes, and this report discusses where, when, and how much ventilation is appropriate in a home, including examination of relevant codes and standards. Choosing the "best" system is not always straightforward; selecting a system involves balancing performance, efficiency, cost, required maintenance, and several other factors.

  13. A systematic and practical method for selecting systems engineering tools

    DEFF Research Database (Denmark)

    Munck, Allan; Madsen, Jan

    2017-01-01

    analyses of the actual needs and the available tools. Grouping needs into categories, allow us to obtain a comprehensive set of requirements for the tools. The entire model-based systems engineering discipline was categorized for a modeling tool case to enable development of a tool specification...... in successful operation since 2013 at GN Hearing. We further utilized the method to select a set of tools that we used on pilot cases at GN Hearing for modeling, simulating and formally verifying embedded systems.......The complexity of many types of systems has grown considerably over the last decades. Using appropriate systems engineering tools therefore becomes increasingly important. Starting the tool selection process can be intimidating because organizations often only have a vague idea about what they need...

  14. Knowledge based expert system approach to instrumentation selection (INSEL

    Directory of Open Access Journals (Sweden)

    S. Barai

    2004-08-01

    Full Text Available The selection of appropriate instrumentation for any structural measurement of civil engineering structure is a complex task. Recent developments in Artificial Intelligence (AI can help in an organized use of experiential knowledge available on instrumentation for laboratory and in-situ measurement. Usually, the instrumentation decision is based on the experience and judgment of experimentalists. The heuristic knowledge available for different types of measurement is domain dependent and the information is scattered in varied knowledge sources. The knowledge engineering techniques can help in capturing the experiential knowledge. This paper demonstrates a prototype knowledge based system for INstrument SELection (INSEL assistant where the experiential knowledge for various structural domains can be captured and utilized for making instrumentation decision. In particular, this Knowledge Based Expert System (KBES encodes the heuristics on measurement and demonstrates the instrument selection process with reference to steel bridges. INSEL runs on a microcomputer and uses an INSIGHT 2+ environment.

  15. Effects of gastric pH on oral drug absorption: In vitro assessment using a dissolution/permeation system reflecting the gastric dissolution process.

    Science.gov (United States)

    Kataoka, Makoto; Fukahori, Miho; Ikemura, Atsumi; Kubota, Ayaka; Higashino, Haruki; Sakuma, Shinji; Yamashita, Shinji

    2016-04-01

    The aim of the present study was to evaluate the effects of gastric pH on the oral absorption of poorly water-soluble drugs using an in vitro system. A dissolution/permeation system (D/P system) equipped with a Caco-2 cell monolayer was used as the in vitro system to evaluate oral drug absorption, while a small vessel filled with simulated gastric fluid (SGF) was used to reflect the gastric dissolution phase. After applying drugs in their solid forms to SGF, SGF solution containing a 1/100 clinical dose of each drug was mixed with the apical solution of the D/P system, which was changed to fasted state-simulated intestinal fluid. Dissolved and permeated amounts on applied amount of drugs were then monitored for 2h. Similar experiments were performed using the same drugs, but without the gastric phase. Oral absorption with or without the gastric phase was predicted in humans based on the amount of the drug that permeated in the D/P system, assuming that the system without the gastric phase reflected human absorption with an elevated gastric pH. The dissolved amounts of basic drugs with poor water solubility, namely albendazole, dipyridamole, and ketoconazole, in the apical solution and their permeation across a Caco-2 cell monolayer were significantly enhanced when the gastric dissolution process was reflected due to the physicochemical properties of basic drugs. These amounts resulted in the prediction of higher oral absorption with normal gastric pH than with high gastric pH. On the other hand, when diclofenac sodium, the salt form of an acidic drug, was applied to the D/P system with the gastric phase, its dissolved and permeated amounts were significantly lower than those without the gastric phase. However, the oral absorption of diclofenac was predicted to be complete (96-98%) irrespective of gastric pH because the permeated amounts of diclofenac under both conditions were sufficiently high to achieve complete absorption. These estimations of the effects of

  16. System of selective disemination of information at ININ

    International Nuclear Information System (INIS)

    Martinez G, M.A.

    1981-01-01

    A study of the systems of selective dissemination of information (SDI) is presented, the concepts for such systems outlined, and their developments traced in advanced countries, its forms of operation and implications for the special libraries. Also the operation of INIS at CIDN (Centro de Informacion y Documentacion Nuclear) is presented, together with recommendations and conclusions to improve the development of this service in Mexico. (author)

  17. Expert hierarchical selection of oil and gas distribution systems

    International Nuclear Information System (INIS)

    Frankel, E.G.

    1991-01-01

    Selection and design of oil and gas distribution systems involves a large number of decision makers and interest groups, as well as many alternative technical, financial, network, operating, management and regulatory options. Their objectives and measures of performance are different. Decision models can be effectively represented by hierarchical structures. A simple deterministic analytic hierarchy process is presented with application to oil and gas distribution systems

  18. Assessment of the performance of a compact concentric spectrometer system for Atmospheric Differential Optical Absorption Spectroscopy

    Science.gov (United States)

    Whyte, C.; Leigh, R. J.; Lobb, D.; Williams, T.; Remedios, J. J.; Cutter, M.; Monks, P. S.

    2009-12-01

    A breadboard demonstrator of a novel UV/VIS grating spectrometer has been developed based upon a concentric arrangement of a spherical meniscus lens, concave spherical mirror and curved diffraction grating suitable for a range of atmospheric remote sensing applications from the ground or space. The spectrometer is compact and provides high optical efficiency and performance benefits over traditional instruments. The concentric design is capable of handling high relative apertures, owing to spherical aberration and comma being near zero at all surfaces. The design also provides correction for transverse chromatic aberration and distortion, in addition to correcting for the distortion called "smile", the curvature of the slit image formed at each wavelength. These properties render this design capable of superior spectral and spatial performance with size and weight budgets significantly lower than standard configurations. This form of spectrometer design offers the potential for exceptionally compact instrument for differential optical absorption spectroscopy (DOAS) applications from LEO, GEO, HAP or ground-based platforms. The breadboard demonstrator has been shown to offer high throughput and a stable Gaussian line shape with a spectral range from 300 to 450 nm at 0.5 nm resolution, suitable for a number of typical DOAS applications.

  19. Assessment of the performance of a compact concentric spectrometer system for Atmospheric Differential Optical Absorption Spectroscopy

    Directory of Open Access Journals (Sweden)

    C. Whyte

    2009-12-01

    Full Text Available A breadboard demonstrator of a novel UV/VIS grating spectrometer has been developed based upon a concentric arrangement of a spherical meniscus lens, concave spherical mirror and curved diffraction grating suitable for a range of atmospheric remote sensing applications from the ground or space. The spectrometer is compact and provides high optical efficiency and performance benefits over traditional instruments. The concentric design is capable of handling high relative apertures, owing to spherical aberration and comma being near zero at all surfaces. The design also provides correction for transverse chromatic aberration and distortion, in addition to correcting for the distortion called "smile", the curvature of the slit image formed at each wavelength. These properties render this design capable of superior spectral and spatial performance with size and weight budgets significantly lower than standard configurations. This form of spectrometer design offers the potential for exceptionally compact instrument for differential optical absorption spectroscopy (DOAS applications from LEO, GEO, HAP or ground-based platforms. The breadboard demonstrator has been shown to offer high throughput and a stable Gaussian line shape with a spectral range from 300 to 450 nm at 0.5 nm resolution, suitable for a number of typical DOAS applications.

  20. Evaluation of the bioavailability of major withanolides of Withania somnifera using an in vitro absorption model system.

    Science.gov (United States)

    Devkar, Santosh T; Kandhare, Amit D; Sloley, Brian D; Jagtap, Suresh D; Lin, James; Tam, Yun K; Katyare, Surendra S; Bodhankar, Subhash L; Hegde, Mahabaleshwar V

    2015-01-01

    Withania somnifera (L.) Dunal, shows several pharmacological properties which are attributed mainly to the withanolides present in the root. The efficacy of medicinally active withanolides constituents depends on the absorption and transportation through the intestinal epithelium. We examined these characteristics by employing the Sino-Veda Madin-Darby canine kidney cells culture system, which under in vitro condition shows the absorption characteristics similar to the human intestinal epithelium. Thus, the aim of the present investigation was to assess the bioavailability of individual withanolides. Withanolides were diluted in Hank's buffered saline at a concentration of 2 μg/ml were tested for permeability studies carried out for 1 h duration. Permeability was measured in terms of efflux pump (P eff) in cm/s. P eff values of withanolide A (WN A), withanone (WNN), 1,2-deoxywithastramonolide (1,2 DWM), withanolide B (WN B), withanoside IV-V (WS IV-V), and withaferin A were 4.05 × 10(-5), 2.06 × 10(-5), 1.97 × 10(-5), 1.80 × 10(-5), 3.19 × 10(-6), 3.03 × 10(-6) and 3.30 × 10(-7) respectively. In conclusion, the nonpolar and low molecular weight compounds (WN A, WNN, 1,2 DWM, and WN B) were highly permeable. As against this, the glycosylated and polar WS IV and WS V showed low permeability. Surprisingly and paradoxically, the highly biologically active withaferin A was completely impermeable, suggesting that further studies possibly using human epithelial colorectal adenocarcinoma (Caco-2) cells may be needed to delineate the absorption characteristics of withanolides, especially withaferin A.

  1. A Comparison between Human Selected, Derived and System ...

    African Journals Online (AJOL)

    admpather

    Using a prototype implementation of our scheme, we compare the results of human-selected, derived passwords and system generated to reveal the practical viability of our approach in terms of results achieved, ease of implementation and use. Keywords: Security, Biometric, Behavioral, Keystroke dynamics, Password.

  2. A Comparison between Human Selected, Derived and System ...

    African Journals Online (AJOL)

    Using a prototype implementation of our scheme, we compare the results of human-selected, derived passwords and system generated to reveal the practical viability of our approach in terms of results achieved, ease of implementation and use. Keywords: Security, Biometric, Behavioral, Keystroke dynamics, Password ...

  3. Corneal manifestations of selected systemic diseases: A review

    Directory of Open Access Journals (Sweden)

    Wayne D.H. Gillan

    2015-08-01

    Full Text Available The corneal manifestations of several selected systemic diseases are reviewed. Metabolic, immunologic and inflammatory and infectious diseases are included. A brief overview of each disease and how it manifests in the cornea is discussed. The importance of conducting a slit-lamp examination on every patient is emphasised.

  4. Online-Expert: An Expert System for Online Database Selection.

    Science.gov (United States)

    Zahir, Sajjad; Chang, Chew Lik

    1992-01-01

    Describes the design and development of a prototype expert system called ONLINE-EXPERT that helps users select online databases and vendors that meet users' needs. Search strategies are discussed; knowledge acquisition and knowledge bases are described; and the Analytic Hierarchy Process (AHP), a decision analysis technique that ranks databases,…

  5. Selection and implementation of a laboratory computer system.

    Science.gov (United States)

    Moritz, V A; McMaster, R; Dillon, T; Mayall, B

    1995-07-01

    The process of selection of a pathology computer system has become increasingly complex as there are an increasing number of facilities that must be provided and stringent performance requirements under heavy computing loads from both human users and machine inputs. Furthermore, the continuing advances in software and hardware technology provide more options and innovative new ways of tackling problems. These factors taken together pose a difficult and complex set of decisions and choices for the system analyst and designer. The selection process followed by the Microbiology Department at Heidelberg Repatriation Hospital included examination of existing systems, development of a functional specification followed by a formal tender process. The successful tenderer was then selected using predefined evaluation criteria. The successful tenderer was a software development company that developed and supplied a system based on a distributed network using a SUN computer as the main processor. The software was written using Informix running on the UNIX operating system. This represents one of the first microbiology systems developed using a commercial relational database and fourth generation language. The advantages of this approach are discussed.

  6. Absorption Spectrum and Density of States of Square, Rectangular, and Triangular Frenkel Exciton Systems with Gaussian Diagonal Disorder

    Directory of Open Access Journals (Sweden)

    Ibrahim Avgin

    2017-01-01

    Full Text Available Using the coherent potential approximation, we investigate the effects of disorder on the optical absorption and the density of states of Frenkel exciton systems on square, rectangular, and triangular lattices with nearest-neighbor interactions and a Gaussian distribution of transition energies. The analysis is based on an elliptic integral approach that gives results over the entire spectrum. The results for the square lattice are in good agreement with the finite-array calculations of Schreiber and Toyozawa. Our findings suggest that the coherent potential approximation can be useful in interpreting the optical properties of two-dimensional systems with dominant nearest-neighbor interactions and Gaussian diagonal disorder provided the optically active states are Frenkel excitons.

  7. Reactor technology assessment and selection utilizing systems engineering approach

    Science.gov (United States)

    Zolkaffly, Muhammed Zulfakar; Han, Ki-In

    2014-02-01

    The first Nuclear power plant (NPP) deployment in a country is a complex process that needs to consider technical, economic and financial aspects along with other aspects like public acceptance. Increased interest in the deployment of new NPPs, both among newcomer countries and those with expanding programs, necessitates the selection of reactor technology among commercially available technologies. This paper reviews the Systems Decision Process (SDP) of Systems Engineering and applies it in selecting the most appropriate reactor technology for the deployment in Malaysia. The integrated qualitative and quantitative analyses employed in the SDP are explored to perform reactor technology assessment and to select the most feasible technology whose design has also to comply with the IAEA standard requirements and other relevant requirements that have been established in this study. A quick Malaysian case study result suggests that the country reside with PWR (pressurized water reactor) technologies with more detailed study to be performed in the future for the selection of the most appropriate reactor technology for Malaysia. The demonstrated technology assessment also proposes an alternative method to systematically and quantitatively select the most appropriate reactor technology.

  8. Hybrid feature selection for supporting lightweight intrusion detection systems

    Science.gov (United States)

    Song, Jianglong; Zhao, Wentao; Liu, Qiang; Wang, Xin

    2017-08-01

    Redundant and irrelevant features not only cause high resource consumption but also degrade the performance of Intrusion Detection Systems (IDS), especially when coping with big data. These features slow down the process of training and testing in network traffic classification. Therefore, a hybrid feature selection approach in combination with wrapper and filter selection is designed in this paper to build a lightweight intrusion detection system. Two main phases are involved in this method. The first phase conducts a preliminary search for an optimal subset of features, in which the chi-square feature selection is utilized. The selected set of features from the previous phase is further refined in the second phase in a wrapper manner, in which the Random Forest(RF) is used to guide the selection process and retain an optimized set of features. After that, we build an RF-based detection model and make a fair comparison with other approaches. The experimental results on NSL-KDD datasets show that our approach results are in higher detection accuracy as well as faster training and testing processes.

  9. Our Selections and Decisions: Inherent Features of the Nervous System?

    Science.gov (United States)

    Rösler, Frank

    The chapter summarizes findings on the neuronal bases of decisionmaking. Taking the phenomenon of selection it will be explained that systems built only from excitatory and inhibitory neuron (populations) have the emergent property of selecting between different alternatives. These considerations suggest that there exists a hierarchical architecture with central selection switches. However, in such a system, functions of selection and decision-making are not localized, but rather emerge from an interaction of several participating networks. These are, on the one hand, networks that process specific input and output representations and, on the other hand, networks that regulate the relative activation/inhibition of the specific input and output networks. These ideas are supported by recent empirical evidence. Moreover, other studies show that rather complex psychological variables, like subjective probability estimates, expected gains and losses, prediction errors, etc., do have biological correlates, i.e., they can be localized in time and space as activation states of neural networks and single cells. These findings suggest that selections and decisions are consequences of an architecture which, seen from a biological perspective, is fully deterministic. However, a transposition of such nomothetic functional principles into the idiographic domain, i.e., using them as elements for comprehensive 'mechanistic' explanations of individual decisions, seems not to be possible because of principle limitations. Therefore, individual decisions will remain predictable by means of probabilistic models alone.

  10. Optimal Subinterval Selection Approach for Power System Transient Stability Simulation

    Directory of Open Access Journals (Sweden)

    Soobae Kim

    2015-10-01

    Full Text Available Power system transient stability analysis requires an appropriate integration time step to avoid numerical instability as well as to reduce computational demands. For fast system dynamics, which vary more rapidly than what the time step covers, a fraction of the time step, called a subinterval, is used. However, the optimal value of this subinterval is not easily determined because the analysis of the system dynamics might be required. This selection is usually made from engineering experiences, and perhaps trial and error. This paper proposes an optimal subinterval selection approach for power system transient stability analysis, which is based on modal analysis using a single machine infinite bus (SMIB system. Fast system dynamics are identified with the modal analysis and the SMIB system is used focusing on fast local modes. An appropriate subinterval time step from the proposed approach can reduce computational burden and achieve accurate simulation responses as well. The performance of the proposed method is demonstrated with the GSO 37-bus system.

  11. Demonstration of an on-site PAFC cogeneration system with waste heat utilization by a new gas absorption chiller

    Energy Technology Data Exchange (ETDEWEB)

    Urata, Tatsuo [Tokyo Gas Company, LTD, Tokyo (Japan)

    1996-12-31

    Analysis and cost reduction of fuel cells is being promoted to achieve commercial on-site phosphoric acid fuel cells (on-site FC). However, for such cells to be effectively utilized, a cogeneration system designed to use the heat generated must be developed at low cost. Room heating and hot-water supply are the most simple and efficient uses of the waste heat of fuel cells. However, due to the short room-heating period of about 4 months in most areas in Japan, the sites having demand for waste heat of fuel cells throughout the year will be limited to hotels and hospitals Tokyo Gas has therefore been developing an on-site FC and the technology to utilize tile waste heat of fuel cells for room cooling by means of an absorption refrigerator. The paper describes the results of fuel cell cogeneration tests conducted on a double effect gas absorption chiller heater with auxiliary waste heat recovery (WGAR) that Tokyo Gas developed in its Energy Technology Research Laboratory.

  12. Detection of gastrointestinal cancer by elastic scattering and absorption spectroscopies with the Los Alamos Optical Biopsy System

    Energy Technology Data Exchange (ETDEWEB)

    Mourant, J.R.; Boyer, J.; Johnson, T.M.; Lacey, J.; Bigio, I.J. [Los Alamos National Lab., NM (United States); Bohorfoush, A. [Wisconsin Medical School, Milwaukee, WI (United States). Dept. of Gastroenterology; Mellow, M. [Univ. of Oklahoma Medical School, Oklahoma City, OK (United States). Dept. of Gastroenterology

    1995-03-01

    The Los Alamos National Laboratory has continued the development of the Optical Biopsy System (OBS) for noninvasive, real-time in situ diagnosis of tissue pathologies. In proceedings of earlier SPIE conferences we reported on clinical measurements in the bladder, and we report here on recent results of clinical tests in the gastrointestinal tract. With the OBS, tissue pathologies are detected/diagnosed using spectral measurements of the elastic optical transport properties (scattering and absorption) of the tissue over a wide range of wavelengths. The use of elastic scattering as the key to optical tissue diagnostics in the OBS is based on the fact that many tissue pathologies, including a majority of cancer forms, exhibit significant architectural changes at the cellular and sub-cellular level. Since the cellular components that cause elastic scattering have dimensions typically on the order of visible to near-IR wavelengths, the elastic (Mie) scattering properties will be wavelength dependent. Thus, morphology and size changes can be expected to cause significant changes m an optical signature that is derived from the wavelength-dependence of elastic scattering. Additionally, the optical geometry of the OBS beneficially enhances its sensitivity for measuring absorption bands. The OBS employs a small fiber-optic probe that is amenable to use with any endoscope or catheter, or to direct surface examination, as well as interstitial needle insertion. Data acquistion/display time is <1 second.

  13. In operando observation system for electrochemical reaction by soft X-ray absorption spectroscopy with potential modulation method

    International Nuclear Information System (INIS)

    Nagasaka, Masanari; Kosugi, Nobuhiro; Yuzawa, Hayato; Horigome, Toshio

    2014-01-01

    In order to investigate local structures of electrolytes in electrochemical reactions under the same scan rate as a typical value 100 mV/s in cyclic voltammetry (CV), we have developed an in operando observation system for electrochemical reactions by soft X-ray absorption spectroscopy (XAS) with a potential modulation method. XAS spectra of electrolytes are measured by using a transmission-type liquid flow cell with built-in electrodes. The electrode potential is swept with a scan rate of 100 mV/s at a fixed photon energy, and soft X-ray absorption coefficients at different potentials are measured at the same time. By repeating the potential modulation at each fixed photon energy, it is possible to measure XAS of electrochemical reaction at the same scan rate as in CV. We have demonstrated successful measurement of the Fe L-edge XAS spectra of aqueous iron sulfate solutions and of the change in valence of Fe ions at different potentials in the Fe redox reaction. The mechanism of these Fe redox processes is discussed by correlating the XAS results with those at different scan rates

  14. Comment on resonant absorption

    International Nuclear Information System (INIS)

    Hammerling, P.

    1977-01-01

    An average over angles of incidence of the usual resonant absorption function is presented. This form is appropriate under experimental conditions where the angles of incidence vary greatly and in an unknown manner. For comparison a lens-ellipsoidal mirror illumination system with a known longitudinal aberration is considered. In the latter example the angles of incidence are readily obtained and the resulting resonance absorption function evaluated. The associated fields are calculated in a similar fashion. (author)

  15. Determination of water quality of ground water in selected Payatas residential areas using ion-selective electrodes (ISE) and atomic absorption spectroscopy (AAS) (determination of NO3, Cl, Pb, Cd, Zn)

    International Nuclear Information System (INIS)

    Tahir, Samsudin A.; Roque, Willie P.; Arididon, Bonifacio D. Jr.; Gardon, Ruel W.

    2003-01-01

    This study aims to determine the water-soluble ions using ion-selective electrodes (ISE) and trace metals using atomic absorption spectroscopy (AAS). Seven water samples were chosen from the thirteen sites, which were gathered from the selected Payatas residential areas in Quezon City. For the trace metals the lowest detection of AAS in lead was obtained in La Brea site and was found to be -0.5 ppm. Lead content has a value of -0.04 ppm and was found to be below the detection limit of 0.1 ppm. The remaining sites obtained high value of lead concentrations in AAS reading. The range of concentration for lead was from 0.5 ppm for La Brea site to 1.4 ppm for Velasco site. The cadmium as trace metal in groundwater samples from Payatas residential area was found to be below the lowest limit of detection ( 3 which is 15.6 ppm and it was obtained by the used of ion selective electrodes (ISE) Horiba model type. Second to it was the La Brea site, which is 10.04 ppm All the other samples do not exceeds to the maximum allowable concentration of nitrate (50.0 ppm), and it ranged from 4.10 ppm for open-well site to 15.6 ppm for Lopez site. In chloride determination, Lagro High School obtained a reading of 57.6 ppm using ISE and it was the highest concentration amount present in seven samples. Next to it was the Ungrin site (36.8 ppm), samples ranged from 6.7 ppm for La Brea site to 57.6 ppm for Lagro high school site. All the samples do not exceeds to the maximum allowable concentration for chloride, which is 250 ppm. (Authors)

  16. Characterization of the EPRI Differential Absorption Lidar (DIAL) System. Final report. [For remote sensing of air pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Baumgartner, R.A.; Depp, J.G.; Evans, W.E.; Grant, W.B.; Hawley, J.G.; March, R.G.; Murray, E.R.; Proctor, E.K.

    1979-12-01

    SRI International designed and constructed a DIfferential Absorption Lidar (DIAL) to provide EPRI with a mobile field system for remote measurements of SO/sub 2/, NO/sub 3/, and O/sub 3/. After field testing the lidar was prepared for the sytem calibration testing where lidar measurements were compared to in situ profiles of SO/sub 2/, NO/sub 2/, and O/sub 3/. This two-week field program determined overall system accuracy and reliability in measuring varying ambient gas concentrations. The lidar was then returned to SRI for detailed subsystem performance evaluations. Improvements were made wherever possible, and the lidar was prepared for further systems tests. Tests were made using an NO/sub 2/ sample chamber to simulate a calibrated NO/sub 2/ plume, and ambient measured NO/sub 2/ concentrations were compared with values from a regional air pollutant monitoring station. Following the local calibration and the systems field tests, SRI evaluated the performance and reliability of the EPRI lidar. Based on that evaluation, SRI undertook a major analysis of possible system improvements. Although the remote measuring capability had been successfully demonstrated in the field program, SRI makes several recommendations for systems improvements which would increase the lidar accuracy and reliability.

  17. Development of the Hybrid Operation Method of a Multi-Geothermal Heat Pump System and Absorption Chiller-Heater

    Directory of Open Access Journals (Sweden)

    Young-Ju Jung

    2015-08-01

    Full Text Available Considerable efforts have been made to reduce the energy consumption of buildings due to the energy crisis, and, the Korean government has supported the use of renewable energy through various grants. Among the possible renewable energy sources, geothermal energy can be used regardless of the outside weather. Therefore, energy consumption can be reduced considerably in summer and winter. Despite the increasing use of renewable energy, the use of renewables has not been operating appropriately. Therefore, this study examined some of the problems of the operation of renewable energy and some possible improvements. The aim of the study is to evaluate a building containing an actual installed multi-geothermal heat pump (Multi-GHP system, in terms of the energy efficiency. In addition, this study evaluated the present control system and the method of complex operation regarding existing heat sources systems and GHP systems through a simulation. The results can be regarded as the result of a hybrid operation method for the improvement of an existing operation. Therefore, the Multi-GHP system energy use of a hybrid operation condition of the Multi-GHP systems and the absorption (ABS chiller-heater system was reduced compared to the operation condition of the Multi-GHP system, and the total energy consumption of the heat source equipment was reduced. The proposed operation plan was evaluated after applying the system to a building. These results showed that the efficient operation of a Multi-GHP hybrid operation method is possible. As a result, the GHP energy use of Multi-GHP systems and the ABS chiller-heater system was reduced by 30% compared to existing operation and the total energy consumption of heat source equipment was reduced by 78%.

  18. Sensor Selection method for IoT systems – focusing on embedded system requirements

    Directory of Open Access Journals (Sweden)

    Hirayama Masayuki

    2016-01-01

    Full Text Available Recently, various types of sensors have been developed. Using these sensors, IoT systems have become hot topics in embedded system domain. However, sensor selections for embedded systems are not well discussed up to now. This paper focuses on embedded system’s features and architecture, and proposes a sensor selection method which is composed seven steps. In addition, we applied the proposed method to a simple example – a sensor selection for computer scored answer sheet reader unit. From this case study, an idea to use FTA in sensor selection is also discussed.

  19. Machine-Vision Systems Selection for Agricultural Vehicles: A Guide

    Directory of Open Access Journals (Sweden)

    Gonzalo Pajares

    2016-11-01

    Full Text Available Machine vision systems are becoming increasingly common onboard agricultural vehicles (autonomous and non-autonomous for different tasks. This paper provides guidelines for selecting machine-vision systems for optimum performance, considering the adverse conditions on these outdoor environments with high variability on the illumination, irregular terrain conditions or different plant growth states, among others. In this regard, three main topics have been conveniently addressed for the best selection: (a spectral bands (visible and infrared; (b imaging sensors and optical systems (including intrinsic parameters and (c geometric visual system arrangement (considering extrinsic parameters and stereovision systems. A general overview, with detailed description and technical support, is provided for each topic with illustrative examples focused on specific applications in agriculture, although they could be applied in different contexts other than agricultural. A case study is provided as a result of research in the RHEA (Robot Fleets for Highly Effective Agriculture and Forestry Management project for effective weed control in maize fields (wide-rows crops, funded by the European Union, where the machine vision system onboard the autonomous vehicles was the most important part of the full perception system, where machine vision was the most relevant. Details and results about crop row detection, weed patches identification, autonomous vehicle guidance and obstacle detection are provided together with a review of methods and approaches on these topics.

  20. A novel lead imprinted polymer as the selective solid phase for extraction and trace detection of lead ions by flame atomic absorption spectrophotometry: Synthesis, characterization and analytical application

    Directory of Open Access Journals (Sweden)

    Homeira Ebrahimzadeh

    2017-05-01

    Full Text Available A novel ion imprinted polymer as the selective solid phase combined with flame atomic absorption spectrometry (FAAS was applied for preconcentration and determination of lead in real samples. In the first step, Pb(II-IIP was synthesized by copolymerization of 2-vinyl pyridine as the functional monomer, ethylene glycol dimethacrylate as the cross-linker, 2,2-azobisisobutyronitrile as the initiator that imprinted with Pb(II as the template ion, 2-amino pyridine as the ligand. Subsequently, the imprinted Pb(II was completely removed by leaching the dried and powdered imprinted polymer with HCl (2 mol L−1. This polymer was characterized by Fourier Transform Infrared (FT-IR spectrometer. The effect of different variables on the extraction efficiency such as type and volume of eluent for extraction, solution’s pH for adsorption, sorption and desorption times was evaluated. Under the optimum conditions: type of eluent, HCl (2 mol L−1; volume of eluent, 5 mL; solution’s pH for sorption, 5; sorption time, 90 min; desorption time, 125 min and breakthrough volume of 750 mL were obtained. Preconcentration factor of the method was about 150. The limit of detection was obtained 0.75 μg L−1 and a dynamic linear range (DLR of 3–150 μg L−1 was found. The maximum sorption retention capacity of Pb(II ions on the imprinted polymer was 85.6 mg g−1. The prepared ion-imprinted polymer particles have an increased selectivity toward Pb(II ions over a range of competing metal ions with the same charge and similar ionic radius. Performance of the present method was evaluated for extraction and determination of Pb(II in water samples at microgram per liter concentration and satisfactory results were obtained (RSD = 2.7%.

  1. Some comments about the comparison between a conventional and a solar powered absorption refrigeration system

    International Nuclear Information System (INIS)

    Corbella, O.D.; Garibotti, C.R.

    1983-08-01

    Two statements about the performance of solar refrigeration systems are discussed. First, concepts of efficiency and coefficient of performance are studied. Second, the influence of inflation and rise of fuel prices are considered, in relation to the comparison between solar and conventional refrigeration systems. (author)

  2. Applications of some microscopic, diffraction and absorption techniques to the study of metal--hydrogen systems

    International Nuclear Information System (INIS)

    Pick, M.A.

    1979-01-01

    Several experimental techniques were reviewed which are used to investigate metal hydrogen systems. The first technique is metallography and optical microscopy. This is a very old technique which was found to be very powerful in the case of metal hydrogen systems. A few examples of such work are shown and the results are discussed

  3. In Vitro-In Vivo Predictive Dissolution-Permeation-Absorption Dynamics of Highly Permeable Drug Extended-Release Tablets via Drug Dissolution/Absorption Simulating System and pH Alteration.

    Science.gov (United States)

    Li, Zi-Qiang; Tian, Shuang; Gu, Hui; Wu, Zeng-Guang; Nyagblordzro, Makafui; Feng, Guo; He, Xin

    2018-05-01

    Each of dissolution and permeation may be a rate-limiting factor in the absorption of oral drug delivery. But the current dissolution test rarely took into consideration of the permeation property. Drug dissolution/absorption simulating system (DDASS) valuably gave an insight into the combination of drug dissolution and permeation processes happening in human gastrointestinal tract. The simulated gastric/intestinal fluid of DDASS was improved in this study to realize the influence of dynamic pH change on the complete oral dosage form. To assess the effectiveness of DDASS, six high-permeability drugs were chosen as model drugs, including theophylline (pK a1  = 3.50, pK a2  = 8.60), diclofenac (pK a  = 4.15), isosorbide 5-mononitrate (pK a  = 7.00), sinomenine (pK a  = 7.98), alfuzosin (pK a  = 8.13), and metoprolol (pK a  = 9.70). A general elution and permeation relationship of their commercially available extended-release tablets was assessed as well as the relationship between the cumulative permeation and the apparent permeability. The correlations between DDASS elution and USP apparatus 2 (USP2) dissolution and also between DDASS permeation and beagle dog absorption were developed to estimate the predictability of DDASS. As a result, the common elution-dissolution relationship was established regardless of some variance in the characteristic behavior between DDASS and USP2 for drugs dependent on the pH for dissolution. Level A in vitro-in vivo correlation between DDASS permeation and dog absorption was developed for drugs with different pKa. The improved DDASS will be a promising tool to provide a screening method on the predictive dissolution-permeation-absorption dynamics of solid drug dosage forms in the early-phase formulation development.

  4. Multitracer study on absorption of radionuclides in atmosphere-plant system

    International Nuclear Information System (INIS)

    Ambe, Shizuko; Shinonaga, Taeko; Watanabe, Tadakazu; Yamaguchi, Isamu

    1996-01-01

    Direct absorption of atmospheric radionuclides by soybean plants was studied using a radioactive multitracer consisting of radionuclides of Sc, Mn, Co, As, Se, Rb, Sr, Y, Eu, Gd, Yb, Hf, Re, and Ir. Soybean seedlings were cultivated at 23degC in a box where multitracer-adsorbed cellulose powders were floating in air. After 28-49 day-cultivation, the plants were harvested and divided into beans (seeds and pods), leaves, stems (inside and outside), and roots. Beans or leaves originating from the same node were collected together. After washing with dilute HCl solution and distilled water, they were dried and then subjected to γ-ray measurement. It was estimated that about 0.2 % of the multitracer was absorbed by the soybean plant, of which 80 % was found in the leaves, and 10 % each in beans and stems. The relative amounts of elements in the beans, leaves, and stems markedly differed depending on the element. Among the elements, Se * was greatly accumulated in the beans, leaves, and stems. Cobalt * , Se * , and Rb * were dominant in the beans, especially in the edible part of seeds. Relative amounts of Mn * , As * , Sr * , and Re * in the seeds were very small. It is noticeable that these nuclides were found in the seeds, though they were not physically exposed to the multitracer-adsorbed cellulose powders during growth. The radioactivities of Sc * , Mn * , Co * , As * , Se * , Rb * , Sr * , Y * , Eu * , Gd * , Yb * , Hf * , Re * , and Ir * were observed for the leaves. Brown leaves accumulated greater amounts of radionuclides than green ones. Main nuclides found in the stem were Sc * , Co * , Se * , Y * , Eu * , Gd * , Yb * , Hf * , and Ir * , a larger part of them on the outside. Trace amounts of Co * , Se * , and Rb * were detected in the roots. Little leakage of the multitracer into the soil was observed. These results indicate that various radionuclides in the atmosphere were directly absorbed through soybean leaves and then transported to the edible part

  5. Narrative absorption

    DEFF Research Database (Denmark)

    Narrative Absorption brings together research from the social sciences and Humanities to solve a number of mysteries: Most of us will have had those moments, of being totally absorbed in a book, a movie, or computer game. Typically we do not have any idea about how we ended up in such a state. No...

  6. Corrosion behaviour of materials selected for FMIT lithium system

    Energy Technology Data Exchange (ETDEWEB)

    Bazinet, G.D.; Brehm, W.F.

    1983-09-01

    The corrosion behavior of selected materials in a liquid lithium environment was studied in support of system and component designs for the Fusion Materials Irradiation Test (FMIT) Facility. Testing conditions ranged from about 3700 to about6500 hours of exposure to flowing lithium at temperatures from 230/sup 0/ to 270/sup 0/C and static lithium at temperatures from 200/sup 0/ to 500/sup 0/C. Principal areas of investigation included lithium corrosion/erosion effects on FMIT lithium system baseline and candidate materials. Material coupons and full-size prototypic components were evaluated to determine corrosion rates, fatigue crack growth rates, structural compatibility, and component acceptability for the lithium system. Based on the results of these studies, concerns regarding system materials and component designs were satisfactorily resolved to support a 20-year design life requirement for the FMIT lithium system.

  7. Corrosion behaviour of materials selected for FMIT lithium system

    International Nuclear Information System (INIS)

    Bazinet, G.D.; Brehm, W.F.

    1983-01-01

    The corrosion behavior of selected materials in a liquid lithium environment was studied in support of system and component designs for the Fusion Materials Irradiation Test (FMIT) Facility. Testing conditions ranged from about 3700 to about6500 hours of exposure to flowing lithium at temperatures from 230 0 to 270 0 C and static lithium at temperatures from 200 0 to 500 0 C. Principal areas of investigation included lithium corrosion/erosion effects on FMIT lithium system baseline and candidate materials. Material coupons and full-size prototypic components were evaluated to determine corrosion rates, fatigue crack growth rates, structural compatibility, and component acceptability for the lithium system. Based on the results of these studies, concerns regarding system materials and component designs were satisfactorily resolved to support a 20-year design life requirement for the FMIT lithium system

  8. Configuration optimization of series flow double-effect water-lithium bromide absorption refrigeration systems by cost minimization

    DEFF Research Database (Denmark)

    Mussati, Sergio F.; Cignitti, Stefano; Mansouri, Seyed Soheil

    2018-01-01

    An optimal process configuration for double-effect water-lithium bromide absorption refrigeration systems with series flow – where the solution is first passed through the high-temperature generator – is obtained by minimization of the total annual cost for a required cooling capacity. To this end......) takes place entirely at the high-temperature zone, and the sizes and operating conditions of the other process units change accordingly in order to meet the problem specification with the minimal total annual cost. This new configuration was obtained for wide ranges of the cooling capacity (150–450 k.......9%, respectively. Most importantly, the obtained optimal solution eliminates the low-temperature solution heat exchanger from the conventional configuration, rendering a new process configuration. The energy integration between the weak and strong lithium bromide solutions (cold and hot streams, respectively...

  9. Utilizing Near-IR Tunable Laser Absorption Spectroscopy to Study Detonation and Combustion Systems

    Science.gov (United States)

    2014-03-27

    A Hencken burner, Rotating Detonation Engine ( RDE ), and a detonation tube were studied using a Time-Devision Multiplexed Tunable Diode Laser...for the three systems. Velocity was calculated for the RDE system using the Doppler shift of the spectral lines. To perform the calculations necessary...however, the CH4 flame did not match as well. The exhaust of the RDE was studied at various equivalence ratios using a hydrogen-air mixture (H2-air

  10. Vibration energy absorption in the whole-body system of a tractor operator

    OpenAIRE

    Jan Szczepaniak; Wojciech Tanaś; Jacek Kromulski

    2014-01-01

    Many people are exposed to whole-body vibration (WBV) in their occupational lives, especially drivers of vehicles such as tractor and trucks. The main categories of effects from WBV are perception degraded comfort interference with activities-impaired health and occurrence of motion sickness. Absorbed power is defined as the power dissipated in a mechanical system as a result of an applied force. The vibration-induced injuries or disorders in a substructure of the human system are primari...

  11. A experimental system for the checking of the absorption of E.C.A.G. graphite; Empilement pour le controle du graphite E.C.A.G

    Energy Technology Data Exchange (ETDEWEB)

    Raievski, V; Vidal, R [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1958-07-01

    A system is described for measuring the mean absorption cross section in thermal neutrons of graphite. This system consists of a graphite stack containing a Ra-Be source and a BF3 counter. A cavity in the stack receives the graphite to be studied or the graphite standard. By comparing the counting rates their absorption ratio can be deduced. The measurement is performed on graphite rods which have been machined before being placed in the pile. It provides the possibility of detecting over a batch of 1 ton of graphite, in a single measurement, a difference in absorption of 0.1 milli barn. (author) [French] On decrit un dispositif permettant de mesurer la section efficace moyenne d'absorption en neutrons thermiques du graphite. Ce dispositif est constitue par un empilement de graphite contenant une source de Ra-Be et un compteur a BF3. Une cavite menagee dans l'empilement peut recevoir le graphite a etudier ou le graphite etalon. Par comparaison des taux de comptage, on en deduit leur rapport d'absorption. La mesure est effectuee sur des barres de graphite usinees avant leur mise en place dans la pile. Elle permet de deceler sur un lot de graphite de 1 tonne, en une seule mesure, une difference d'absorption de 0,1 millibarn. (auteur)

  12. Design of mini-multi-gas monitoring system based on IR absorption

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Q.L.; Zhang, W.D.; Xue, C.Y.; Xiong, J.J.; Ma, Y.C.; Wen, F. [Northern University of China, Taiyuan (China)

    2008-07-15

    In this paper, a novel non-dispersive infrared ray (IR) gas detection system is described. Conventional devices typically include several primary components: a broadband source (usually all incandescent filament), a rotating chopper shutter, a narrow-band filter, a sample tube and a detector. But we mainly use file mini-multi-channel detector, electrical modulation means and mini-gas-cell structure. To solve the problems of gas accidents in coal mines, and for family safety that results from using gas, this new IR detection system with integration, miniaturization and non-moving parts has been developed. It is based on the principle that certain gases absorb infrared radiation at specific (and often unique) wavelengths. The infrared detection optics principle used in developing this system is mainly analyzed. The idea of multi-gas detection is introduced and guided through the analysis of the single-gas detection. Through researching the design of cell structure, a cell with integration and miniaturization has been devised. By taking a single-chip microcomputer (SCM) as intelligence handling, the functional block diagram of a gas detection system is designed with the analyzing and devising of its hardware and software system. The way of data transmission on a controller area network (CAN) bus and wireless data transmission mode is explained. This system has reached the technology requirement of lower power consumption, mini-volume, wide measure range, and is able to realize multi-gas detection.

  13. Quality assurance considerations for nuclear power system selection

    International Nuclear Information System (INIS)

    Bender, M.

    1977-01-01

    The key quality assurance principle to be applied in nuclear system selection is to establish that the technological basis is understood and used properly. Knowledgeable and capable personnel with experience in the application are needed, and they must have access to appropriate engineering, laboratory, and manufacturing facilities. A suitable balance must be maintained between the responsibilities of the seller-supplier and the purchaser-owner to assure an even-handed treatment of the implementation program. Safety and reliability must be inherent to the regulatory framework. There must be flexibility in the purchaser-owner resources to overcome unanticipated adversity. Given these quality assurance elements, the nuclear system selection process should result in a high probability that the performance objectives will be satisfied

  14. Design of an operations manager selection system in service encounter

    Directory of Open Access Journals (Sweden)

    Tanawin Nunthaphanich

    2015-10-01

    Full Text Available The purpose of this study is to provide criteria for selecting operations managers at the ‘service encounter’ for mobile telecommunication companies, and develop a system for this multi-criteria decision-making scheme based on the Analytical Hierarchy Process (AHP. There are three main criteria for evaluating the capability of service-encounter operation managers: (1 the ability to design service process; (2 the ability to operate service process; (3 the ability to conduct improvement. The AHP operation manager selection tool was developed based on the complex problems at the service encounter. It was created as a decision support system which was used to recruit and evaluate operations managers’ capability for the purpose of career advancement.

  15. Decision Analysis System for Selection of Appropriate Decontamination Technologies

    International Nuclear Information System (INIS)

    Ebadian, M.A.; Boudreaux, J.F.; Chinta, S.; Zanakis, S.H.

    1998-01-01

    The principal objective for designing Decision Analysis System for Decontamination (DASD) is to support DOE-EM's endeavor to employ the most efficient and effective technologies for treating radiologically contaminated surfaces while minimizing personnel and environmental risks. DASD will provide a tool for environmental decision makers to improve the quality, consistency, and efficacy of their technology selection decisions. The system will facilitate methodical comparisons between innovative and baseline decontamination technologies and aid in identifying the most suitable technologies for performing surface decontamination at DOE environmental restoration sites

  16. Environmental and economical aspects of selected energy system

    International Nuclear Information System (INIS)

    1991-11-01

    An analysis of environmental and economical aspects of selected renewable energy systems is presented. The aim was to provide a basis for estimating the competitive status in each case, to review the consequences of technological development, to identify attractive markets and to evaluate the effects of various economic conditions. Calculation methods are described and individual solar heating systems are compared to oil-fired boilers, boilers fired with solid fuels are compared to oil-fired boilers and straw-fired cogeneration plants are compared with coal, fuel-oil and straw-fired district heating plants. Results are presented in the form of tables and graphs. (AB)

  17. The effects of water absorption on an ester vinyl resin system

    Directory of Open Access Journals (Sweden)

    Ledjane Lima Sobrinho

    2009-09-01

    Full Text Available Derakene is a vinyl ester resin largely employed as matrix for polymeric based composite systems. In this work, the performance of such polymeric system was evaluated considering the effect of hygrothermal aging. The mechanical and thermal properties were examined for the processed material before and after ageing in water at 60 ºC for a maximum period of 64 days. Both analyses indicated the occurrence of post cure of the system after 16 days due to exposition at 60 ºC in water, which was also confirmed by analyses in samples with post cure treatment. Moreover, it was observed plasticizing of resin after 36 and 64 days of ageing. Micro structural and fracture surface analyses were carried out in order to characterize the samples. The appearance of surface voids was also observed.

  18. Förster resonance energy transfer, absorption and emission spectra in multichromophoric systems. II. Hybrid cumulant expansion.

    Science.gov (United States)

    Ma, Jian; Moix, Jeremy; Cao, Jianshu

    2015-03-07

    We develop a hybrid cumulant expansion method to account for the system-bath entanglement in the emission spectrum in the multi-chromophoric Förster transfer rate. In traditional perturbative treatments, the emission spectrum is usually expanded with respect to the system-bath coupling term in both real and imaginary time. This perturbative treatment gives a reliable absorption spectrum, where the bath is Gaussian and only the real-time expansion is involved. For the emission spectrum, the initial state is an entangled state of the system plus bath. Traditional perturbative methods are problematic when the excitations are delocalized and the energy gap is larger than the thermal energy, since the second-order expansion cannot predict the displacement of the bath. In the present method, the real-time dynamics is carried out by using the 2nd-order cumulant expansion method, while the displacement of the bath is treated more accurately by utilizing the exact reduced density matrix of the system. In a sense, the hybrid cumulant expansion is based on a generalized version of linear response theory with entangled initial states.

  19. Cultural selection drives the evolution of human communication systems.

    Science.gov (United States)

    Tamariz, Monica; Ellison, T Mark; Barr, Dale J; Fay, Nicolas

    2014-08-07

    Human communication systems evolve culturally, but the evolutionary mechanisms that drive this evolution are not well understood. Against a baseline that communication variants spread in a population following neutral evolutionary dynamics (also known as drift models), we tested the role of two cultural selection models: coordination- and content-biased. We constructed a parametrized mixed probabilistic model of the spread of communicative variants in four 8-person laboratory micro-societies engaged in a simple communication game. We found that selectionist models, working in combination, explain the majority of the empirical data. The best-fitting parameter setting includes an egocentric bias and a content bias, suggesting that participants retained their own previously used communicative variants unless they encountered a superior (content-biased) variant, in which case it was adopted. This novel pattern of results suggests that (i) a theory of the cultural evolution of human communication systems must integrate selectionist models and (ii) human communication systems are functionally adaptive complex systems.

  20. Functional Analysis Of A Selected Airport’s System

    Directory of Open Access Journals (Sweden)

    Dudek Ewa

    2015-11-01

    Full Text Available In this paper two selected airport’s systems (Flight Information System and Public Address Voice Annunciation are defined and described. Then they are used to create an integrated unit, with the presentation of its way of functioning and a schematic picture. The author names main purposes of the integration process, serving to counteract negative consequences arising from implementation of the increasing number of systems on transport objects. In the following part of the article functional analysis of the integrated unit is carried out, defining system’s possible states of work and relations between them. Utilization of mathematical apparatus allows to calculate probabilities of system staying in the respective states, as well as system’s time indexes. Presented results are a fundament for the further analysis of this matter.

  1. Cell culture models of biological barriers: in vitro test systems for drug absorption and delivery

    National Research Council Canada - National Science Library

    Lehr, Claus-Michael

    2002-01-01

    ... may be reprinted or reproduced or utilized in any form or by any electronic, mechanical, or other means, now known or hereafter invented, including photocopying and recording, or in any information storage or retrieval system, without permission in writing from the publishers. Every effort has been made to ensure that the advice and information in this book is t...

  2. MEMBRANOUS FLOWS IN GAS-LIQUID COLLECTORS-REGENERATORS OF SOLAR ABSORPTIVE SYSTEMS FEATURES

    Directory of Open Access Journals (Sweden)

    Doroshenko А.V.

    2009-12-01

    Full Text Available Article is devoted to the creation of new generation of solar collectors of the gas-liquid type, intended for use in alternative refrigerating and conditioning systems of drying-evaporating type with direct solar regeneration of absorbent. Special attention is given to the study of membranous flows features on inclined surfaces, including questions of such flows stability.

  3. Thermodynamic and economic studies of two new high efficient power-cooling cogeneration systems based on Kalina and absorption refrigeration cycles

    International Nuclear Information System (INIS)

    Rashidi, Jouan; Ifaei, Pouya; Esfahani, Iman Janghorban; Ataei, Abtin; Yoo, Chang Kyoo

    2016-01-01

    Highlights: • Proposing two new power and cooling cogeneration systems based on absorption chillers and Kalina cycles. • Model-based comparison through thermodynamic and economic standpoints. • Investigating sensitivity of system performance and costs to the key parameters. • Reducing total annual costs of the base system up to 8% by cogeneration. • Increasing thermal efficiency up to 4.9% despite of cooling generation. - Abstract: Two new power and cooling cogeneration systems based on Kalina cycle (KC) and absorption refrigeration cycle (AC) are proposed and studied from thermodynamic and economic viewpoints. The first proposed system, Kalina power-cooling cycle (KPCC), combines the refrigerant loop of the water-ammonia absorption chiller, consisting of an evaporator and two throttling valves with the KC. A portion of the KC mass flow enters the evaporator to generate cooling after being condensed in the KPCC system. KPCC is a flexible system adapting power and cooling cogeneration to the demand. The second proposed system, Kalina lithium bromide absorption chiller cycle (KLACC), consists of the KC and a single effect lithium bromide-water absorption chiller (AC_L_i_B_r_-_w_a_t_e_r). The KC subsystem discharges heat to the AC_L_i_B_r_-_w_a_t_e_r desorber before condensing in the condenser. The performance and economic aspects of both proposed systems are analyzed and compared with the stand alone KC. A parametric analysis is conducted to evaluate the sensitivity of efficiencies and the generated power and cooling quantities to the key operating variables. The results showed that, thermal efficiency and total annual costs decreased by 5.6% and 8% for KPCC system but increased 4.9% and 58% for KLACC system, respectively. Since the power-cooling efficiency of KLACC is 42% higher than KPCC it can be applied where the aim is cooling generation without considering economic aspects.

  4. BiOSS: A system for biomedical ontology selection.

    Science.gov (United States)

    Martínez-Romero, Marcos; Vázquez-Naya, José M; Pereira, Javier; Pazos, Alejandro

    2014-04-01

    In biomedical informatics, ontologies are considered a key technology for annotating, retrieving and sharing the huge volume of publicly available data. Due to the increasing amount, complexity and variety of existing biomedical ontologies, choosing the ones to be used in a semantic annotation problem or to design a specific application is a difficult task. As a consequence, the design of approaches and tools addressed to facilitate the selection of biomedical ontologies is becoming a priority. In this paper we present BiOSS, a novel system for the selection of biomedical ontologies. BiOSS evaluates the adequacy of an ontology to a given domain according to three different criteria: (1) the extent to which the ontology covers the domain; (2) the semantic richness of the ontology in the domain; (3) the popularity of the ontology in the biomedical community. BiOSS has been applied to 5 representative problems of ontology selection. It also has been compared to existing methods and tools. Results are promising and show the usefulness of BiOSS to solve real-world ontology selection problems. BiOSS is openly available both as a web tool and a web service. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  5. Resource evaluation and site selection for microalgae production systems

    Energy Technology Data Exchange (ETDEWEB)

    Maxwell, E.L.; Folger, A.G.; Hogg, S.E.

    1985-05-01

    Climate, land, and water resource requirements of microalgae production systems (MPS) were examined relative to construction costs, operating costs, and biomass productivity. The objective was the stratification of the southwestern United States into zones of relative suitability for MPS. Maps of climate (insolation, freeze-free period, precipitation, evaporation, thunderstorm days), land (use/cover, ownership, slope), and water (saline groundwater) resource parameters were obtained. These maps were transformed into digital overlays permitting the cell-by-cell compositing of selected resource parameters to form maps representing relative productivity, make-up water, climate suitability, land suitability, water suitability, and overall suitability. The Southwest was selected for this study because of its high levels of insolation, saline water resources, and large areas of relatively low valued land. The stratification maps cannot be used for the selection of specific sites because of their low resolution (12,455-acre cells). They can be used to guide future resource studies and site selection efforts, however, by limiting these efforts to the most suitable regions. Future efforts should concentrate on saline water resources, for which only limited data are currently available. 13 refs., 44 figs., 5 tabs.

  6. Theoretical modeling of deuteration-induced shifts of the 0-0 bands in absorption spectra of selected aromatic amines: the role of the double-well potential.

    Science.gov (United States)

    Andrzejak, Marcin; Kolek, Przemysław

    2013-12-05

    The harmonic approximation fails for inversion of the NH2 group in the ground state of aromatic amines as this vibration is characterized by a symmetric double-well potential with relatively small energy barrier. In such cases, the standard harmonic vibrational analysis is inapplicable: the inversion frequency calculated for the bottom of the potential well is strongly overestimated, while it attains imaginary values for the planar conformation of the molecule. The model calculations are discussed taking explicitly into account the presence of the double-well potential. The study is initially focused on reproduction of the deuteration-induced shifts of the 0-0 absorption band for anthranilic acid. The (incorrect) harmonic frequency of the NH2 inversion is replaced by a better one, obtained from numerical calculations employing a simple, quartic-quadratic model for the double-well potential, which is parametrized using just the harmonic frequency of the inversion and the height of the energy barrier. This operation brings theoretical results to qualitative agreement with experiment. A still better match is achieved with a modified version of the model that accounts for mixing of the NH2 inversion mode with other normal modes while retaining the initial simplicity of one-dimensional approach. The corrected results show surprisingly good accuracy, with deviations of the calculated shifts from the experimental values reduced to less than 5 cm(-1). In order to test the performance of the model for systems with higher energy barrier for the NH2 inversion, we have measured the LIF excitation spectra of three different amminobenzonitriles. Partial assignment of the 0-0 bands has been achieved based on their relative intensities for samples with different isotopic exchange ratios. Calculated shifts are in excellent agreement with experimental values for the identified bands. Theoretical predictions are used to complete the assignment of the 0-0 bands in the spectra of the

  7. Absorptive products

    International Nuclear Information System (INIS)

    Assarsson, P.G.; King, P.A.

    1976-01-01

    Applications for hydrophile gels produced by the radiation induced cross-linking in aqueous solution of polyethylene oxide and starch, as described in Norwegian patent 133501 (INIS RN 281494), such as sanitary napkins (diapers) and sanitary towels, are discussed. The process itself is also discussed and results, expressed as the percentage of insoluble gel and its absorptive capacity for saline solution as functions of the ratio of polyethylene oxide to starch and the radiation dose, are presented. (JIW)

  8. Unshifted Metastable He I* Mini-broad Absorption Line System in the Narrow-line Type 1 Quasar SDSS J080248.18+551328.9

    Science.gov (United States)

    Ji, Tuo; Zhou, Hongyan; Jiang, Peng; Wang, Tinggui; Ge, Jian; Wang, Huiyuan; Komossa, S.; Hamann, Fred; Zuther, Jens; Liu, Wenjuan; Lu, Honglin; Zuo, Wenwen; Yang, Chenwei; Yuan, Weimin

    2015-02-01

    We report the identification of an unusual absorption-line system in the quasar SDSS J080248.18+551328.9 and present a detailed study of the system, incorporating follow-up optical and near-IR spectroscopy. A few tens of absorption lines are detected, including He I*, Fe II*, and Ni II*, which arise from metastable or excited levels, as well as resonant lines in Mg I, Mg II, Fe II, Mn II, and Ca II. All of the isolated absorption lines show the same profile of width Δv ~ 1500 km s-1 centered at a common redshift as that of the quasar emission lines, such as [O II], [S II], and hydrogen Paschen and Balmer series. With narrow Balmer lines, strong optical Fe II multiplets, and weak [O III] doublets, its emission-line spectrum is typical for that of a narrow-line Seyfert 1 galaxy (NLS1). We have derived reliable measurements of the gas-phase column densities of the absorbing ions/levels. Photoionization modeling indicates that the absorber has a density of n H ~ (1.0-2.5) × 105 cm-3 and a column density of N H ~ (1.0-3.2) × 1021 cm-2 and is located at R ~100-250 pc from the central supermassive black hole. The location of the absorber, the symmetric profile of the absorption lines, and the coincidence of the absorption- and emission-line centroid jointly suggest that the absorption gas originates from the host galaxy and is plausibly accelerated by stellar processes, such as stellar winds and/or supernova explosions. The implications for the detection of such a peculiar absorption-line system in an NLS1 are discussed in the context of coevolution between supermassive black hole growth and host galaxy buildup.

  9. Selected topics in special nuclear materials safeguard system design

    International Nuclear Information System (INIS)

    King, L.L.; Thatcher, C.D.; Clarke, J.D.; Rodriguez, M.P.

    1991-01-01

    During the past two decades the improvements in circuit integration have given rise to many new applications in digital processing technology by continuously reducing the unit cost of processing power. Along with this increase in processing power a corresponding decrease in circuit volume has been achieved. Progress has been so swift that new classes of applications become feasible every 2 or 3 years. This is especially true in the application of proven new technology to special nuclear materials (SNM) safeguard systems. Several areas of application were investigated in establishing the performance requirements for the SNM safeguard system. These included the improvements in material control and accountability and surveillance by using multiple sensors to continuously monitor SNM inventory within the selected value(s); establishing a system architecture to provide capabilities needed for present and future performance requirements; and limiting operating manpower exposure to radiation. This paper describes two selected topics in the application of state-of-the-art, well-proven technology to SNM safeguard system design

  10. An interactive roof bolting selection and performance system

    Energy Technology Data Exchange (ETDEWEB)

    Agioutantis, Z.; Stiakakis, C.; Stiakakis, N. [Technical Univ. of Crete, Chania (Greece); Karmis, M. [Virginia Polytechnic Inst. and State Univ. (United States)

    2001-07-01

    In the last decades, bolting has become one of the most dominant support methods in underground construction, including both mining as well as civil engineering applications. A variety of bolt types has been developed in order to meet the support needs of different geological and geotechnical settings. The selection of the appropriate bolt type, as well as the troubleshooting procedures in case of failure or suspected failure, are often complex and require extensive experience. To facilitate bolt type selection as well as troubleshooting, various tools have been presented in the form of nomograms, computer programs or trouble shooting guides. The approach described in this paper incorporates information and data developed by laboratory and field investigations and has led to the development of a dynamic knowledge base system that can aid in the selection of appropriate bolting systems and, also, help troubleshoot existing installations. Additionally, the user can enhance the functionality of the existing database with site-specific information and geological behavior as experienced by field personnel. The package is developed as a Windows trademark based application, where data is stored in Microsoft Access trademark database. (orig.)

  11. On Secure NOMA Systems with Transmit Antenna Selection Schemes

    KAUST Repository

    Lei, Hongjiang; Zhang, Jianming; Park, Kihong; Xu, Peng; Ansari, Imran Shafique; Pan, Gaofeng; Alomair, Basel; Alouini, Mohamed-Slim

    2017-01-01

    This paper investigates the secrecy performance of a two-user downlink non-orthogonal multiple access systems. Both single-input and single-output and multiple-input and singleoutput systems with different transmit antenna selection (TAS) strategies are considered. Depending on whether the base station has the global channel state information of both the main and wiretap channels, the exact closed-form expressions for the secrecy outage probability (SOP) with suboptimal antenna selection and optimal antenna selection schemes are obtained and compared with the traditional space-time transmission scheme. To obtain further insights, the asymptotic analysis of the SOP in high average channel power gains regime is presented and it is found that the secrecy diversity order for all the TAS schemes with fixed power allocation is zero. Furthermore, an effective power allocation scheme is proposed to obtain the nonzero diversity order with all the TAS schemes. Monte-Carlo simulations are performed to verify the proposed analytical results.

  12. On Secure NOMA Systems with Transmit Antenna Selection Schemes

    KAUST Repository

    Lei, Hongjiang

    2017-08-09

    This paper investigates the secrecy performance of a two-user downlink non-orthogonal multiple access systems. Both single-input and single-output and multiple-input and singleoutput systems with different transmit antenna selection (TAS) strategies are considered. Depending on whether the base station has the global channel state information of both the main and wiretap channels, the exact closed-form expressions for the secrecy outage probability (SOP) with suboptimal antenna selection and optimal antenna selection schemes are obtained and compared with the traditional space-time transmission scheme. To obtain further insights, the asymptotic analysis of the SOP in high average channel power gains regime is presented and it is found that the secrecy diversity order for all the TAS schemes with fixed power allocation is zero. Furthermore, an effective power allocation scheme is proposed to obtain the nonzero diversity order with all the TAS schemes. Monte-Carlo simulations are performed to verify the proposed analytical results.

  13. Modeling of intensity-modulated continuous-wave laser absorption spectrometer systems for atmospheric CO(2) column measurements.

    Science.gov (United States)

    Lin, Bing; Ismail, Syed; Wallace Harrison, F; Browell, Edward V; Nehrir, Amin R; Dobler, Jeremy; Moore, Berrien; Refaat, Tamer; Kooi, Susan A

    2013-10-10

    The focus of this study is to model and validate the performance of intensity-modulated continuous-wave (IM-CW) CO(2) laser absorption spectrometer (LAS) systems and their CO(2) column measurements from airborne and satellite platforms. The model accounts for all fundamental physics of the instruments and their related CO(2) measurement environments, and the modeling results are presented statistically from simulation ensembles that include noise sources and uncertainties related to the LAS instruments and the measurement environments. The characteristics of simulated LAS systems are based on existing technologies and their implementation in existing systems. The modeled instruments are specifically assumed to be IM-CW LAS systems such as the Exelis' airborne multifunctional fiber laser lidar (MFLL) operating in the 1.57 μm CO(2) absorption band. Atmospheric effects due to variations in CO(2), solar radiation, and thin clouds, are also included in the model. Model results are shown to agree well with LAS atmospheric CO(2) measurement performance. For example, the relative bias errors of both MFLL simulated and measured CO(2) differential optical depths were found to agree to within a few tenths of a percent when compared to the in situ observations from the flight of 3 August 2011 over Railroad Valley (RRV), Nevada, during the summer 2011 flight campaign. In addition, the horizontal variations in the model CO(2) differential optical depths were also found to be consistent with those from MFLL measurements. In general, the modeled and measured signal-to-noise ratios (SNRs) of the CO(2) column differential optical depths (τd) agreed to within about 30%. Model simulations of a spaceborne IM-CW LAS system in a 390 km dawn/dusk orbit for CO(2) column measurements showed that with a total of 42 W of transmitted power for one offline and two different sideline channels (placed at different locations on the side of the CO(2) absorption line), the accuracy of the

  14. 77 FR 27263 - Computer Matching Between the Selective Service System and the Department of Education

    Science.gov (United States)

    2012-05-09

    ... SELECTIVE SERVICE SYSTEM Computer Matching Between the Selective Service System and the Department of Education AGENCY: Selective Service System. Action: Notice. In accordance with the Privacy Act of... of Participating Agencies The Selective Service System (SSS) and the Department of Education (ED). 2...

  15. Social absorption capability, systems of innovation and manufactured export response to preferential trade incentives

    DEFF Research Database (Denmark)

    Na-Allah, Abdelrasaq; Muchie, Mammo

    2012-01-01

    In many extant analyses of non-reciprocal system of trade preferences, it is typical to focus on the details of market access value of tarrif concessions as explanation for why export beneficiaries may or may not respond to include very often the role that supply related factors can, and do play...... & Opportunity Act apparel trade incentive is used as a classical illustration of this proposition. It is shown that the comparative efficiency of Lesetho, despite emerging from a relatively weak trade performance potential background, in recording the highest level of export success among beneficiaries...

  16. Effect of Moisture Exchange on Interface Formation in the Repair System Studied by X-ray Absorption

    Directory of Open Access Journals (Sweden)

    Mladena Lukovic

    2015-12-01

    Full Text Available In concrete repair systems, material properties of the repair material and the interface are greatly influenced by the moisture exchange between the repair material and the substrate. If the substrate is dry, it can absorb water from the repair material and reduce its effective water-to-cement ratio (w/c. This further affects the hydration rate of cement based material. In addition to the change in hydration rate, void content at the interface between the two materials is also affected. In this research, the influence of moisture exchange on the void content in the repair system as a function of initial saturation level of the substrate is investigated. Repair systems with varying level of substrate saturation are made. Moisture exchange in these repair systems as a function of time is monitored by the X-ray absorption technique. After a specified curing age (3 d, the internal microstructure of the repair systems was captured by micro-computed X-ray tomography (CT-scanning. From reconstructed images, different phases in the repair system (repair material, substrate, voids can be distinguished. In order to quantify the void content, voids were thresholded and their percentage was calculated. It was found that significantly more voids form when the substrate is dry prior to application of the repair material. Air, initially filling voids and pores of the dry substrate, is being released due to the moisture exchange. As a result, air voids remain entrapped in the repair material close to the interface. These voids are found to form as a continuation of pre-existing surface voids in the substrate. Knowledge about moisture exchange and its effects provides engineers with the basis for recommendations about substrate preconditioning in practice.

  17. Effect of Moisture Exchange on Interface Formation in the Repair System Studied by X-ray Absorption.

    Science.gov (United States)

    Lukovic, Mladena; Ye, Guang

    2015-12-22

    In concrete repair systems, material properties of the repair material and the interface are greatly influenced by the moisture exchange between the repair material and the substrate. If the substrate is dry, it can absorb water from the repair material and reduce its effective water-to-cement ratio (w/c). This further affects the hydration rate of cement based material. In addition to the change in hydration rate, void content at the interface between the two materials is also affected. In this research, the influence of moisture exchange on the void content in the repair system as a function of initial saturation level of the substrate is investigated. Repair systems with varying level of substrate saturation are made. Moisture exchange in these repair systems as a function of time is monitored by the X-ray absorption technique. After a specified curing age (3 d), the internal microstructure of the repair systems was captured by micro-computed X-ray tomography (CT-scanning). From reconstructed images, different phases in the repair system (repair material, substrate, voids) can be distinguished. In order to quantify the void content, voids were thresholded and their percentage was calculated. It was found that significantly more voids form when the substrate is dry prior to application of the repair material. Air, initially filling voids and pores of the dry substrate, is being released due to the moisture exchange. As a result, air voids remain entrapped in the repair material close to the interface. These voids are found to form as a continuation of pre-existing surface voids in the substrate. Knowledge about moisture exchange and its effects provides engineers with the basis for recommendations about substrate preconditioning in practice.

  18. Load Absorption Characteristics of Tyre Production Waste Rubber for Playground Floor Systems

    Directory of Open Access Journals (Sweden)

    Abdul Ghani A.N.

    2014-01-01

    Full Text Available The floor surfaces where slides and swings are placed in parks and playrooms should be soft and thick to ensure that whenever a child falls, the surface can withstand the impact and minimize injuries to the child. Shredded tyres from waste tyres or waste rubber from tyre manufacturing could become beneficial as shock absorber material which can be used as a playground floor. In this study, rubber cubes and rubber pads with 5%, 8% and 10% SBR mixes were prepared for mechanical testing. Two types of floor design surfaces with and without plywood on the surface were assembled for the shock test. Gmax and HIC of this waste rubber flooring system were investigated using the compression test for the rubber cube and the drop test for the rubber pad. The criteria of general protection standards are 200g for optimum acceleration and 1000 for HIC. The Gmax and HIC results indicated that the material and system could ensure a safe fall from up to 1.0m height.

  19. Mathematical modelling of heat absorption capacity of containment spray system in a 700 MWe PHWR

    International Nuclear Information System (INIS)

    Kota, Sampath Bharadwaj; Ali, Seik Mansoor; Balasubramaniyan, V.

    2015-01-01

    This paper presents a mathematical model for estimating the heat removal by containment spray system in the post Loss of Coolant Accident (LOCA) environment. The procedure involves firstly, the calculation of heat removal rates by droplets of spray dispersed in the air-steam mixture by an appropriate direct contact condensation model accounting for the presence of non-condensable gas (air). Parametric influence of droplet size, ambient pressure and temperature on heat flux is brought out. It was found that the heat flux is inversely proportional to the ambient pressure and diameter. A spray module was subsequently developed and incorporated into an in-house containment thermal hydraulics code. The pressure and temperature transients in a 700 MWe PHWR containment building following a Large Break LOCA was obtained using this code. The efficacy of the spray in condensing the steam is shown by comparing the transients with and without the operation of spray system. Parametric studies are also conducted with respect to droplet size and flow rate of water droplet spray. The details of the investigation are presented and discussed in this paper. (author)

  20. Experimental determination of line strengths for selected carbon monoxide and carbon dioxide absorption lines at temperatures between 295 and 1250 K

    International Nuclear Information System (INIS)

    Medvecz, P.J.; Nichols, K.M.

    1994-01-01

    Fourier transform infrared absorption spectroscopy has been used for the determination of the line strengths of 41 CO and CO 2 absorption lines at temperatures between 295 and 1250 K. The CO vibrational-rotational lines were from the P branch of the fundamental absorption band (2150--1950 cm -1 ) while the CO 2 vibrational-rotational lines were from the far wing of the R branch of the ν 3 fundamental band (2395--2380 cm -1 ). The intensities of the lines were measured from absorption spectra recorded in a high-temperature gas cell containing known concentrations of CO/CO 2 /N 2 gas mixtures at atmospheric pressure. Absorption spectra were recorded through the cell with the use of a moderate-resolution Fourier transform infrared spectrometer. The absorption spectra were mathematically corrected for distortions resulting from the finite resolution of the spectrometer and for peak overlap. Line strength measurements were made from the corrected peaks by using the Bouguer-Lambert law and assuming a Lorentzian line profile. The experimentally obtained line strengths were evaluated by statistical calculations, by consideration of the validity of the Bouguer-Lambert assumption for these data, by comparison with existing room-temperature and high-temperature data, and by comparison with theoretical calculations. For CO, the statistical analysis suggests that the reported values have an uncertainty of ±10--12%, which is similar to the observed discrepancies with other reported values at room temperature. At high temperatures, the difference between these data and previously reported data and theoretical predictions is less than 10%. For CO 2 , the statistical uncertainty associated with the line strength calculations is less than 5%, which is also the approximate level of agreement with existing room-temperature data

  1. An Antibiotic Selection System For Protein Overproducing Bacteria

    DEFF Research Database (Denmark)

    Rennig, Maja; Nørholm, Morten

    2015-01-01

    Introduction: Protein overproduction is a major bottleneck for analyses of membrane proteins and for the construction of cell factories. Screening for optimized protein production can be very time consuming. In this study we show that the coupling of antibiotic resistance to poorly produced...... membrane proteins of Escherichia coli can be used as a fast and simple selection system for protein overproduction.Methods: We designed an expression plasmid encoding the gene of interest and an additional, inducible antibiotic resistance marker. Both genes were linked by a hairpin structure...... that translationally couples the genes. Consequently, high expressing gene variants also allow for higher production of the coupled antibiotic resistance marker. Therefore, high expressing gene variants in a library can be determined either by plating the expression library on selection plates or by growing...

  2. Optical Selection Rule of Excitons in Gapped Chiral Fermion Systems

    Science.gov (United States)

    Zhang, Xiaoou; Shan, Wen-Yu; Xiao, Di

    2018-02-01

    We show that the exciton optical selection rule in gapped chiral fermion systems is governed by their winding number w , a topological quantity of the Bloch bands. Specifically, in a CN-invariant chiral fermion system, the angular momentum of bright exciton states is given by w ±1 +n N with n being an integer. We demonstrate our theory by proposing two chiral fermion systems capable of hosting dark s -like excitons: gapped surface states of a topological crystalline insulator with C4 rotational symmetry and biased 3 R -stacked MoS2 bilayers. In the latter case, we show that gating can be used to tune the s -like excitons from bright to dark by changing the winding number. Our theory thus provides a pathway to electrical control of optical transitions in two-dimensional material.

  3. The selection criteria elements of X-ray optics system

    Science.gov (United States)

    Plotnikova, I. V.; Chicherina, N. V.; Bays, S. S.; Bildanov, R. G.; Stary, O.

    2018-01-01

    At the design of new modifications of x-ray tomography there are difficulties in the right choice of elements of X-ray optical system. Now this problem is solved by practical consideration, selection of values of the corresponding parameters - tension on an x-ray tube taking into account the thickness and type of the studied material. For reduction of time and labor input of design it is necessary to create the criteria of the choice, to determine key parameters and characteristics of elements. In the article two main elements of X-ray optical system - an x-ray tube and the detector of x-ray radiation - are considered. Criteria of the choice of elements, their key characteristics, the main dependences of parameters, quality indicators and also recommendations according to the choice of elements of x-ray systems are received.

  4. System for selecting relevant information for decision support.

    Science.gov (United States)

    Kalina, Jan; Seidl, Libor; Zvára, Karel; Grünfeldová, Hana; Slovák, Dalibor; Zvárová, Jana

    2013-01-01

    We implemented a prototype of a decision support system called SIR which has a form of a web-based classification service for diagnostic decision support. The system has the ability to select the most relevant variables and to learn a classification rule, which is guaranteed to be suitable also for high-dimensional measurements. The classification system can be useful for clinicians in primary care to support their decision-making tasks with relevant information extracted from any available clinical study. The implemented prototype was tested on a sample of patients in a cardiological study and performs an information extraction from a high-dimensional set containing both clinical and gene expression data.

  5. Selecting a pharmacy layout design using a weighted scoring system.

    Science.gov (United States)

    McDowell, Alissa L; Huang, Yu-Li

    2012-05-01

    A weighted scoring system was used to select a pharmacy layout redesign. Facilities layout design techniques were applied at a local hospital pharmacy using a step-by-step design process. The process involved observing and analyzing the current situation, observing the current available space, completing activity flow charts of the pharmacy processes, completing communication and material relationship charts to detail which areas in the pharmacy were related to one another and how they were related, researching applications in other pharmacies or in scholarly works that could be beneficial, numerically defining space requirements for areas within the pharmacy, measuring the available space within the pharmacy, developing a set of preliminary designs, and modifying preliminary designs so they were all acceptable to the pharmacy staff. To select a final layout that could be implemented in the pharmacy, those layouts were compared via a weighted scoring system. The weighted aspect further allowed additional emphasis on categories based on their effect on pharmacy performance. The results produced a beneficial layout design as determined through simulated models of the pharmacy operation that more effectively allocated and strategically located space to improve transportation distances and materials handling, employee utilization, and ergonomics. Facilities layout designs for a hospital pharmacy were evaluated using a weighted scoring system to identify a design that was superior to both the current layout and alternative layouts in terms of feasibility, cost, patient safety, employee safety, flexibility, robustness, transportation distance, employee utilization, objective adherence, maintainability, usability, and environmental impact.

  6. Atomic absorption instrument functional description

    International Nuclear Information System (INIS)

    Bystroff, R.I.; Boyle, W.G. Jr.; Barton, G.W. Jr.

    1976-01-01

    This report describes a proposed system for automating atomic absorption analysis. The system consists of two atomic absorption instruments and an automatic sampler that can be attached to either instrument. A computer program controls the sampling and gathers data. The program then uses the data to perform bookkeeping, data processing, and report writing

  7. Recent Advances in Delivery Systems and Therapeutics of Cinnarizine: A Poorly Water Soluble Drug with Absorption Window in Stomach

    Directory of Open Access Journals (Sweden)

    Smita Raghuvanshi

    2014-01-01

    Full Text Available Low solubility causing low dissolution in gastrointestinal tract is the major problem for drugs meant for systemic action after oral administration, like cinnarizine. Pharmaceutical products of cinnarizine are commercialized globally as immediate release preparations presenting low absorption with low and erratic bioavailability. Approaches to enhance bioavailability are widely cited in the literature. An attempt has been made to review the bioavailability complications and clinical therapeutics of poorly water soluble drug: cinnarizine. The interest of writing this paper is to summarize the pharmacokinetic limitations of drug with special focus on strategies to improvise bioavailability along with effectiveness of novel dosage forms to circumvent the obstacle. The paper provides insight to the approaches to overcome low and erratic bioavailability of cinnarizine by cyclodextrin complexes and novel dosage forms: self-nanoemulsifying systems and buoyant microparticulates. Nanoformulations need to systematically explored in future, for their new clinical role in prophylaxis of migraine attacks in children. Clinical reports have affirmed the role of cinnarizine in migraine prophylaxis. Research needs to be dedicated to develop dosage forms for efficacious bioavailability and drug directly to brain.

  8. Modeling and experimental validation of the solar loop for absorption solar cooling system using double-glazed collectors

    International Nuclear Information System (INIS)

    Marc, Olivier; Praene, Jean-Philippe; Bastide, Alain; Lucas, Franck

    2011-01-01

    Solar cooling applied to buildings is without a doubt an interesting alternative for reducing energy consumption in traditional mechanical steam compression air conditioning systems. The study of these systems should have a closely purely fundamental approach including the development of numerical models in order to predict the overall installation performance. The final objective is to estimate cooling capacity, power consumption, and overall installation performance with relation to outside factors (solar irradiation, outside temperature...). The first stage in this work consists of estimating the primary energy produced by the solar collector field. The estimation of this primary energy is crucial to ensure the evaluation of the cooling capacity and therefore the cooling distribution and thermal comfort in the building. Indeed, the absorption chiller performance is directly related to its heat source. This study presents dynamic models for double glazing solar collectors and compares the results of the simulation with experimental results taken from our test bench (two collectors). In the second part, we present an extensive collector field model (36 collectors) from our solar cooling installation at The University Institute of Technology in St Pierre, Reunion Island as well as our stratified tank storage model. A comparison of the simulation results with real scale solar experimental data taken from our installation enables validation of the double glazing solar collector and stratified tank dynamic models.

  9. Comparative studies of H absorption/desorption kinetics and evaporation of liquid lithium in different porous systems and free surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Oyarzabal, E., E-mail: eider.oyarzabal@externos.ciemat.es [Ass. Euratom-Ciemat, Av. Complutense 22, 28040 Madrid (Spain); Calle de Guzmán el Bueno, 133, 28003 Madrid (Spain); Martín-Rojo, A.B. [Ass. Euratom-Ciemat, Av. Complutense 22, 28040 Madrid (Spain); Calle de Guzmán el Bueno, 133, 28003 Madrid (Spain); Tabarés, F.L. [Ass. Euratom-Ciemat, Av. Complutense 22, 28040 Madrid (Spain)

    2017-04-15

    In the present work, a study of the two most relevant properties of liquid lithium with respect to its suitability as a Plasma Facing Component (PFC) element in a Reactor, namely, its evaporation rate and the uptake/release of hydrogen, eventually leading to the formation of a stable hydride was carried out for Li in different porous systems and Li as a free surface. These properties were characterized in a temperature range of 200–500 °C. The H{sub 2} absorption kinetics at low pressure (<1torr) were measured for the different studied porous systems and then outgassed. Particle balance and chemical analysis were used to assess the retention properties of lithium for each case. Thermal Desorption Spectroscopy (TDS) analysis was used for the assessment of possible hydride formation. Evaporation rates were determined by using a Quartz Microbalance (QMB). A significant reduction of the evaporation rate was observed when Li was trapped in a microstructure of sintered stainless steel with a characteristic porous size of 5–10 μm. On the other hand, a negligible rate of H{sub 2} uptake was found at temperatures above 500 °C in all cases.

  10. Distributive estimation of frequency selective channels for massive MIMO systems

    KAUST Repository

    Zaib, Alam

    2015-12-28

    We consider frequency selective channel estimation in the uplink of massive MIMO-OFDM systems, where our major concern is complexity. A low complexity distributed LMMSE algorithm is proposed that attains near optimal channel impulse response (CIR) estimates from noisy observations at receive antenna array. In proposed method, every antenna estimates the CIRs of its neighborhood followed by recursive sharing of estimates with immediate neighbors. At each step, every antenna calculates the weighted average of shared estimates which converges to near optimal LMMSE solution. The simulation results validate the near optimal performance of proposed algorithm in terms of mean square error (MSE). © 2015 EURASIP.

  11. A review and guidance for pattern selection in spatiotemporal system

    Science.gov (United States)

    Wang, Chunni; Ma, Jun

    2018-03-01

    Pattern estimation and selection in media can give important clues to understand the collective response to external stimulus by detecting the observable variables. Both reaction-diffusion systems (RDs) and neuronal networks can be treated as multi-agent systems from molecular level, intrinsic cooperation, competition. An external stimulus or attack can cause collapse of spatial order and distribution, while appropriate noise can enhance the consensus in the spatiotemporal systems. Pattern formation and synchronization stability can bridge isolated oscillators and the network by coupling these nodes with appropriate connection types. As a result, the dynamical behaviors can be detected and discussed by developing different spatial patterns and realizing network synchronization. Indeed, the collective response of network and multi-agent system depends on the local kinetics of nodes and cells. It is better to know the standard bifurcation analysis and stability control schemes before dealing with network problems. In this review, dynamics discussion and synchronization control on low-dimensional systems, pattern formation and synchronization stability on network, wave stability in RDs and neuronal network are summarized. Finally, possible guidance is presented when some physical effects such as polarization field and electromagnetic induction are considered.

  12. Addressing selected problems of the modelling of digital control systems

    International Nuclear Information System (INIS)

    Sedlak, J.

    2004-12-01

    The introduction of digital systems to practical activities at nuclear power plants brings about new requirements for their modelling for the purposes of reliability analyses required for plant licensing as well as for inclusion into PSA studies and subsequent use in applications for the assessment of events, limits and conditions, and risk monitoring. It is very important to assess, both qualitatively and quantitatively, the effect of this change on operational safety. The report describes selected specific features of reliability analysis of digital system and recommends methodological procedures. The chapters of the report are as follows: (1) Flexibility and multifunctionality of the system. (2) General framework of reliability analyses (Understanding the system; Qualitative analysis; Quantitative analysis; Assessment of results, comparison against criteria; Documenting system reliability analyses; Asking for comments and their evaluation); and (3) Suitable reliability models (Reliability models of basic events; Monitored components with repair immediately following defect or failure; Periodically tested components; Constant unavailability (probability of failure to demand); Application of reliability models for electronic components; Example of failure rate decomposition; Example modified for diagnosis successfulness; Transfer of reliability analyses to PSA; Common cause failures - CCF; Software backup and CCF type failures, software versus hardware). (P.A.)

  13. Materials selection guidelines for geothermal energy utilization systems

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, P.F. II; Conover, M.F.

    1981-01-01

    This manual includes geothermal fluid chemistry, corrosion test data, and materials operating experience. Systems using geothermal energy in El Salvador, Iceland, Italy, Japan, Mexico, New Zealand, and the United States are described. The manual provides materials selection guidelines for surface equipment of future geothermal energy systems. The key chemical species that are significant in determining corrosiveness of geothermal fluids are identified. The utilization modes of geothermal energy are defined as well as the various physical fluid parameters that affect corrosiveness. Both detailed and summarized results of materials performance tests and applicable operating experiences from forty sites throughout the world are presented. The application of various non-metal materials in geothermal environments are discussed. Included in appendices are: corrosion behavior of specific alloy classes in geothermal fluids, corrosion in seawater desalination plants, worldwide geothermal power production, DOE-sponsored utilization projects, plant availability, relative costs of alloys, and composition of alloys. (MHR)

  14. System Quality Characteristics for Selecting Mobile Learning Applications

    Directory of Open Access Journals (Sweden)

    Mohamed SARRAB

    2015-10-01

    Full Text Available The majority of M-learning (Mobile learning applications available today are developed for the formal learning and education environment. These applications are characterized by the improvement in the interaction between learners and instructors to provide high interaction and flexibility to the learning process. M-learning is gaining increased recognition and adoption by different organizations. With the high number of M-learning applications available today, making the right decision about which, application to choose can be quite challenging. To date there is no complete and well defined set of system characteristics for such M-learning applications. This paper presents system quality characteristics for selecting M-learning applications based on the result of a systematic review conducted in this domain.

  15. Selection of initial events of accelerator driven subcritical system

    International Nuclear Information System (INIS)

    Wang Qianglong; Hu Liqin; Wang Jiaqun; Li Yazhou; Yang Zhiyi

    2013-01-01

    The Probabilistic Safety Assessment (PSA) is an important tool in reactor safety analysis and a significant reference to the design and operation of reactor. It is the origin and foundation of the PSA for a reactor to select the initial events. Accelerator Driven Subcritical System (ADS) has advanced design characteristics, complicated subsystems and little engineering and operating experience, which makes it much more difficult to identify the initial events of ADS. Based on the current design project of ADS, the system's safety characteristics and special issues were analyzed in this article. After a series of deductions with Master Logic Diagram (MLD) and considering the relating experience of other advanced research reactors, a preliminary initial events was listed finally, which provided the foundation for the next safety assessment. (authors)

  16. Radiator selection for Space Station Solar Dynamic Power Systems

    Science.gov (United States)

    Fleming, Mike; Hoehn, Frank

    A study was conducted to define the best radiator for heat rejection of the Space Station Solar Dynamic Power System. Included in the study were radiators for both the Organic Rankine Cycle and Closed Brayton Cycle heat engines. A number of potential approaches were considered for the Organic Rankine Cycle and a constructable radiator was chosen. Detailed optimizations of this concept were conducted resulting in a baseline for inclusion into the ORC Preliminary Design. A number of approaches were also considered for the CBC radiator. For this application a deployed pumped liquid radiator was selected which was also refined resulting in a baseline for the CBC preliminary design. This paper reports the results and methodology of these studies and describes the preliminary designs of the Space Station Solar Dynamic Power System radiators for both of the candidate heat engine cycles.

  17. Absorption of carbon dioxide and isotope exchange rate of carbon in a reaction system between carbon dioxide and carbamic acid

    International Nuclear Information System (INIS)

    Takeshita, Kenji; Kitamoto, Asashi

    1985-01-01

    The performance of isotope separation of carbon-13 by chemical exchange between carbon dioxide and carbamic acid was studied. The working fluid used in the study was a solution of DNBA, (C 4 H 9 ) 2 NH and n-octane mixture. Factors related to the isotope exchange rate were measured, such as the absorption rate of carbon dioxide into the solution of DNBA and n-octane, the isotope exchange rate and the separation factor in the reaction between CO 2 and carbamic acid. The absorption of CO 2 into the working fluid was the sum of chemical absorption by DNBA and physical absorption by n-octane. The absorption of carbon dioxide into the working fluid was negligible at temperatures over 90 0 C, but increased gradually at lower temperatures. Carbon dioxide was absorbed into DNBA by chemical absorption, and DNBA was converted to carbamic acid by the reaction. The reaction for synthesis and decomposition of carbamic acid was reversible. The separation factor in equilibrium reached a large value at lower temperatures. The isotope exchange rate between gas and liquid was proportional to the product of the concentration of carbamic acid and the concentration of CO 2 by physical absorption. The isotope separation of carbon by chemical exchange reaction is better operated under the conditions of lower temperature and higher pressure. (author)

  18. Corrosion behavior of selected materials in lithium bromide solution for the application absorption chillers; Korrosionsverhalten ausgewaehlter Werkstoffe in Lithiumbromid-Loesung fuer den Anwendungsfall Absorptionskaeltemaschinen

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, B. [ZAE Bayern, Garching (Germany)

    2004-07-01

    Absorption chillers on the basis of lithium bromide-water are interesting systems for efficient and energy-saving supply of coldness. The heating energy for the propulsion of the chiller could result ideally from renewable energies, e.g. solar energy, or waste heating energy from industry. The chiller can work as a multiple-stage process for increasing the energy efficiency. For the three-stage-plants, in the generator temperatures of up to 200-220 C are necessary. The factors high temperature, high halogenide concentration (lithium bromide) and the presence of water vapour lead to a very high corrosive exposure of the materials. In that reason the task of the present report was the consideration of commercial materials and inhibitors concerning their suitability for the application in triple-effect-chillers. The measurements were carried out under identical conditions, but in unmoved solution and excluding the contact with air. The result of the investigations showed that stainless steel has been identified as a promising material for this application. Furthermore we have found out that the type of the inhibitor and the interaction of different phases have a strong influence on the corrosion processes. (Abstract Copyright [2004], Wiley Periodicals, Inc.) [German] Absorptionskaeltemaschinen auf der Basis von Lithiumbromid-Wasser stellen eine interessante Moeglichkeit zur effizienten und energiesparenden Versorgung mit Kaelte dar. Die zum Antrieb erforderliche Waermeenergie kann idealerweise aus regenerativen Energien, wie z.B. Solarwaerme, oder Abwaerme aus der Industrie bereitgestellt werden. Um die Energieeffizienz zu steigern, koennen die Prozesse mehrstufig betrieben werden. Bei den dreistufigen, sogenannten Triple-Effekt-Anlagen, sind im Generator Temperaturen bis zu etwa 200-220 C erforderlich. Die Faktoren hohe Temperatur, hohe Halogenidkonzentration (Lithiumbromid) und die Anwesenheit von Wasserdampf fuehren zu einer besonders starken korrosiven

  19. Selenium speciation using capillary electrophoresis coupled with modified electrothermal atomic absorption spectrometry after selective extraction with 5-sulfosalicylic acid functionalized magnetic nanoparticles.

    Science.gov (United States)

    Yan, Lizhen; Deng, Biyang; Shen, Caiying; Long, Chanjuan; Deng, Qiufen; Tao, Chunyao

    2015-05-22

    A new method for selenium speciation in fermented bean curd wastewater and juice was described. This method involved sample extraction with 5-sulfosalicylic acid (SSA)-functionalized silica-coated magnetic nanoparticles (SMNPs), capillary electrophoresis (CE) separation, and online detection with a modified electrothermal atomic absorption spectrometry (ETAAS) system. The modified interface for ETAAS allowed for the introduction of CE effluent directly through the end of the graphite tube. Elimination of the upper injection hole of the graphite tube reduced the loss of the anlayte and enhanced the detection sensitivity. The SSA-SMNPs were synthesized and used to extract trace amounts of selenite [Se(IV)], selenite [Se(VI)], selenomethionine (SeMet), and selenocystine (SeCys2) from dilute samples. The concentration enrichment factors for Se(VI), Se(IV), SeMet, and SeCys2 were 21, 29, 18, and 12, respectively, using the SSA-SMNPs extraction. The limits of detection for Se(VI), Se(IV), SeMet, and SeCys2 were 0.18, 0.17, 0.54, 0.49ngmL(-1), respectively. The RSD values (n=6) of method for intraday were observed between 0.7% and 2.9%. The RSD values of method for interday were less than 3.5%. The linear range of Se(VI) and Se(IV) were in the range of 0.5-200ngmL(-1), and the linear ranges of SeMet and SeCys2 were 2-500 and 2-1000ngmL(-1), respectively. The detection limits of this method were improved by 10 times due to the enrichment by the SSA-SMNP extraction. The contents of Se(VI) and Se(IV) in fermented bean curd wastewater were measured as 3.83 and 2.62ngmL(-1), respectively. The contents of Se(VI), Se(IV), SeMet, and SeCys2 in fermented bean curd juice were determined as 6.39, 4.08, 2.77, and 4.00ngmL(-1), respectively. The recoveries were in the range of 99.14-104.5% and the RSDs (n=6) of recoveries between 0.82% and 3.5%. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Selected parameters of moulding sands for designing quality control systems

    Directory of Open Access Journals (Sweden)

    J. Jakubski

    2010-07-01

    Full Text Available One of the modern methods of production optimisation are artificial neural networks. Neural networks owe their popularity to the fact thatthey are convenient tools, which can be utilised in a wide scope of problems. They are capable of reflecting complex functions. Especiallytheir non-linearity should be emphasised. They are gaining wider and wider application in the foundry industry, among others, to controlmelting processes in cupolas and arc furnaces, designing castings and supply systems, control of moulding sands treatments, prediction ofproperties of cast alloys as well as selecting die casting.An attempt of the application neural networks to the quality control of moulding sands with bentonite is presented in the paper. This isa method of assessing the suitability of moulding sands by finding correlations in between individual parameters, by means of artificialneural network systems. The presented investigations were performed with the application of the Statistica 8.0 program.The investigations were aimed at the selection of the proper kind of a neural network for prediction a sand moistness on the bases ofcertain moulding sand properties such as: permeability, compactibility and friability. These parameters – determined as sand moistness functions - were introduced as initial parameters.Application of the Statistica program allowed for an automatic selection of the most suitable network for the reflection of dependencies and interactions existing among the proposed parameters. The best results were obtained for unidirectional multi-layer perception network (MLP. The neural network sensitivity to individual moulding sand parameters was determined, which allowed to reject not important parameters when constructing the network.