WorldWideScience

Sample records for high conversion rates

  1. A system approach to high quality picture-rate conversion

    NARCIS (Netherlands)

    Bartels, C.L.L.; Cordes, C.N.; Riemens, B.; Haan, de G.

    2010-01-01

    Various techniques have been implemented to improve the motion portrayal of flat-panel displays, of which the widespread introduction of motion-compensated picture-rate conversion systems is an essential part. However, a careful design of such systems is critical as they have the potential to

  2. Key requirements for high quality picture-rate conversion.

    NARCIS (Netherlands)

    Cordes, C.N.; Haan, de G.

    2009-01-01

    Past LCD-TV generations suffered from a poor motion portrayal, causing the blurring of moving objects. Hence, various techniques have been implemented to improve their motion portrayal, of which the widespread introduction of motion compensated picture-rate conversion in TV systems is an essential

  3. High-Order Model and Dynamic Filtering for Frame Rate Up-Conversion.

    Science.gov (United States)

    Bao, Wenbo; Zhang, Xiaoyun; Chen, Li; Ding, Lianghui; Gao, Zhiyong

    2018-08-01

    This paper proposes a novel frame rate up-conversion method through high-order model and dynamic filtering (HOMDF) for video pixels. Unlike the constant brightness and linear motion assumptions in traditional methods, the intensity and position of the video pixels are both modeled with high-order polynomials in terms of time. Then, the key problem of our method is to estimate the polynomial coefficients that represent the pixel's intensity variation, velocity, and acceleration. We propose to solve it with two energy objectives: one minimizes the auto-regressive prediction error of intensity variation by its past samples, and the other minimizes video frame's reconstruction error along the motion trajectory. To efficiently address the optimization problem for these coefficients, we propose the dynamic filtering solution inspired by video's temporal coherence. The optimal estimation of these coefficients is reformulated into a dynamic fusion of the prior estimate from pixel's temporal predecessor and the maximum likelihood estimate from current new observation. Finally, frame rate up-conversion is implemented using motion-compensated interpolation by pixel-wise intensity variation and motion trajectory. Benefited from the advanced model and dynamic filtering, the interpolated frame has much better visual quality. Extensive experiments on the natural and synthesized videos demonstrate the superiority of HOMDF over the state-of-the-art methods in both subjective and objective comparisons.

  4. Cardiothoracic and Vascular Surgeons Achieve High Rates of K-Award Conversion Into R01 Funding.

    Science.gov (United States)

    Narahari, Adishesh K; Mehaffey, J Hunter; Hawkins, Robert B; Baderdinni, Pranav K; Chandrabhatla, Anirudha S; Tribble, Curtis G; Kron, Irving L; Roeser, Mark E; Walters, Dustin M; Ailawadi, Gorav

    2018-03-14

    Obtaining National Institutes of Health (NIH) R01 funding remains extremely difficult. The utility of career development grants (K awards) for achieving the goal of R01 funding remains debated, particularly for surgeon-scientists. We examined the success rate for cardiothoracic and vascular (CTV) surgeons compared to other specialties in converting K-level grants into R01 equivalents. All K (K08 and K23) grants awarded to surgeons by the NIH between 1992-2017 were identified through NIH RePORTER, an online database combining funding, publications, and patents. Only grants awarded to CTV surgeons were included. Grants active within the past year were excluded. Mann-Whitney U-tests and Chi-squared tests were used to compare groups. A total of 62 K grants awarded to CTV surgeons were identified during this period. Sixteen grants were still active within the last year and excluded from analysis. Twenty-two (48%) of the remaining K awardees successfully transitioned to an R01 or equivalent grant. Awardees with successful conversion published 9 publications per K grant compared to 4 publications for those who did not convert successfully (p=0.01). The median time for successful conversion to an R grant was 5.0 years after the K award start date. Importantly, the 10-year conversion rate to R01 was equal for CTV surgeons compared to other clinician-investigators (52.6% vs 42.5%). CTV surgeons have an equal 10-year conversion rate to first R01 award compared to other clinicians. These data suggest that NIH achieves a good return on investment when funding CTV surgeon-scientists with K-level funding. Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  5. Occlusion classifiers for picture rate conversion

    NARCIS (Netherlands)

    Bartels, C.L.L.; Haan, de G.; Rabbani, Majid

    2009-01-01

    Occlusion detection is an essential ingredient in high quality picture rate up-conversion and view interpolation applications. Many integrated approaches to occlusion detection and classification have been proposed, particularly in the stereo literature. However, due to their high complexity and

  6. A low-temperature partial-oxidation-methanol micro reformer with high fuel conversion rate and hydrogen production yield

    International Nuclear Information System (INIS)

    Wang, Hsueh-Sheng; Huang, Kuo-Yang; Huang, Yuh-Jeen; Su, Yu-Chuan; Tseng, Fan-Gang

    2015-01-01

    Highlights: • A low-operating temperature of the POM-mode micro methanol reformer is obtained. • The effect of channel design on the performance is studied. • The effect of solid content and binder’ ratio on the performance is studied. • The centrifugal process is benefit for the modification of performance. • 98% of methanol conversion rate of the micro reformer can be obtained at 180 °C. - Abstract: A partial oxidation methanol micro reformer (POM-μReformer) with finger-shaped channels for low operating temperature and high conversing efficiency is proposed in this study. The micro reformer employs POM reaction for low temperature operation (less than 200 °C), exothermic reaction, and quick start-up, as well as air feeding capability; and the finger type reaction chambers for increasing catalyst loading as well as reaction area for performance enhancement. In this study, centrifugal technique was introduced to assist on the catalyst loading with high amount and uniform distribution. The solid content (S), binder’s ratio (B), and channel design (the ratio between channel’s length and width, R) were investigated in detail to optimize the design parameters. Scanning electron microscopy (SEM), gas chromatography (GC), and inductively coupled plasma-mass spectrometer (ICP-MS) were employed to analyze the performance of the POM-μReformer. The result depicted that the catalyst content and reactive area could be much improved at the optimized condition, and the conversion rate and hydrogen selectivity approached 97.9% and 97.4%, respectively, at a very low operating temperature of 180 °C with scarce or no binder in catalyst. The POM-μReformer can supply hydrogen to fuel cells by generating 2.23 J/min for 80% H 2 utilization and 60% fuel cell efficiency at 2 ml/min of supplied reactant gas, including methanol, oxygen and argon at a mixing ratio of 12.2%, 6.1% and 81.7%, respectively

  7. Rating Instructional Conversations: A Guide

    OpenAIRE

    Rueda, Robert; Goldenberg, Claude; Gallimore, Ronald

    1992-01-01

    The current focus on more effective ways to foster literacy in school-age children, especially language minority students, has led to the development of alternative instructional approaches. One such approach is the instructional conversation (IC), based on early work in the Hawaiian Kamehameha Elementary Education Project (KEEP), on neo-Vygotskian theory, and on recent classroom-based research on reading comprehension. The present report outlines preliminary efforts to operationaliz...

  8. Analysis of 62 hybrid assembled human Y chromosomes exposes rapid structural changes and high rates of gene conversion.

    Directory of Open Access Journals (Sweden)

    Laurits Skov

    2017-08-01

    Full Text Available The human Y-chromosome does not recombine across its male-specific part and is therefore an excellent marker of human migrations. It also plays an important role in male fertility. However, its evolution is difficult to fully understand because of repetitive sequences, inverted repeats and the potentially large role of gene conversion. Here we perform an evolutionary analysis of 62 Y-chromosomes of Danish descent sequenced using a wide range of library insert sizes and high coverage, thus allowing large regions of these chromosomes to be well assembled. These include 17 father-son pairs, which we use to validate variation calling. Using a recent method that can integrate variants based on both mapping and de novo assembly, we genotype 10898 SNVs and 2903 indels (max length of 27241 bp in our sample and show by father-son concordance and experimental validation that the non-recurrent SNP and indel variation on the Y chromosome tree is called very accurately. This includes variation called in a 0.9 Mb centromeric heterochromatic region, which is by far the most variable in the Y chromosome. Among the variation is also longer sequence-stretches not present in the reference genome but shared with the chimpanzee Y chromosome. We analyzed 2.7 Mb of large inverted repeats (palindromes for variation patterns among the two palindrome arms and identified 603 mutation and 416 gene conversions events. We find clear evidence for GC-biased gene conversion in the palindromes (and a balancing AT mutation bias, but irrespective of this, also a strong bias towards gene conversion towards the ancestral state, suggesting that palindromic gene conversion may alleviate Muller's ratchet. Finally, we also find a large number of large-scale gene duplications and deletions in the palindromic regions (at least 24 and find that such events can consist of complex combinations of simultaneous insertions and deletions of long stretches of the Y chromosome.

  9. Modeling the Influence of Diffusion-Controlled Reactions and Residual Termination and Deactivation on the Rate and Control of Bulk ATRP at High Conversions

    Directory of Open Access Journals (Sweden)

    Ali Mohammad Rabea

    2015-04-01

    Full Text Available In high-conversion atom transfer radical polymerization (ATRP, all the reactions, such as radical termination, radical deactivation, dormant chain activation, monomer propagation, etc. could become diffusion controlled sooner or later, depending on relative diffusivities of the involved reacting species. These diffusion-controlled reactions directly affect the rate of polymerization and the control of polymer molecular weight. A model is developed to investigate the influence of diffusion-controlled reactions on the high conversion ATRP kinetics. Model simulation reveals that diffusion-controlled termination slightly increases the rate, but it is the diffusion-controlled deactivation that causes auto-acceleration in the rate (“gel effect” and loss of control. At high conversions, radical chains are “trapped” because of high molecular weight. However, radical centers can still migrate through (1 radical deactivation–activation cycles and (2 monomer propagation, which introduce “residual termination” reactions. It is found that the “residual termination” does not have much influence on the polymerization kinetics. The migration of radical centers through propagation can however facilitate catalytic deactivation of radicals, which improves the control of polymer molecular weight to some extent. Dormant chain activation and monomer propagation also become diffusion controlled and finally stop the polymerization when the system approaches its glass state.

  10. Analysis of 62 hybrid assembled human Y chromosomes exposes rapid structural changes and high rates of gene conversion

    DEFF Research Database (Denmark)

    Gonzalez-Izarzugaza, Jose Maria; Skov, Laurits; Maretty, Lasse

    2017-01-01

    with the chimpanzee Y chromosome. We analyzed 2.7 Mb of large inverted repeats (palindromes) for variation patterns among the two palindrome arms and identified 603 mutation and 416 gene conversions events. We find clear evidence for GC-biased gene conversion in the palindromes (and a balancing AT mutation bias...

  11. Analysis of 62 hybrid assembled human Y chromosomes exposes rapid structural changes and high rates of gene conversion

    DEFF Research Database (Denmark)

    Gonzalez-Izarzugaza, Jose Maria; Skov, Laurits; Maretty, Lasse

    2017-01-01

    The human Y-chromosome does not recombine across its male-specific part and is therefore an excellent marker of human migrations. It also plays an important role in male fertility. However, its evolution is difficult to fully understand because of repetitive sequences, inverted repeats and the po......The human Y-chromosome does not recombine across its male-specific part and is therefore an excellent marker of human migrations. It also plays an important role in male fertility. However, its evolution is difficult to fully understand because of repetitive sequences, inverted repeats...... and the potentially large role of gene conversion. Here we perform an evolutionary analysis of 62 Y-chromosomes of Danish descent sequenced using a wide range of library insert sizes and high coverage, thus allowing large regions of these chromosomes to be well assembled. These include 17 father-son pairs, which we...... use to validate variation calling. Using a recent method that can integrate variants based on both mapping and de novo assembly, we genotype 10898 SNVs and 2903 indels (max length of 27241 bp) in our sample and show by father-son concordance and experimental validation that the non-recurrent SNP...

  12. Conversion rate optimization in Finnish online businesses

    OpenAIRE

    Ratia, Miramaria; Ruoho, Vilma

    2016-01-01

    Conversion rate optimization (CRO) is an unfamiliar term to many online business owners even though it has become almost as important as search engine optimization is in e-commerce today. It is a method that is used to turn passive visitors into active users in order to improve a website’s performance. The main objective of this thesis was to find out what kinds of conversion rate optimization methods do Finnish small and medium-sized online businesses use. The thesis also studies what ar...

  13. The weak conversion rate in quark matter

    International Nuclear Information System (INIS)

    Heiselberg, H.

    1992-01-01

    The weak conversion rate of strange to down quarks, s + u ↔ u + d, is calculated analytically for degenerate u, d and s quark matter to leading orders in temperature and deviations from chemical equilibrium. The rate is applied to burning of neutron matter into quark matter, to evaporation from quark nuggets in the early universe, for estimating the lifetime of strangelets, and to pulsar glitches

  14. Development of high conversion boiling water reactor

    International Nuclear Information System (INIS)

    Yamashita, Jun-ichi; Mochida, Takaaki; Uchikawa, Sadao.

    1988-01-01

    It is expected that the period of LWRs being the main source of electric power supply becomes long, therefore, the development of next generation LWRs placing emphasis on the effective utilization of uranium resources and the improvement of economical efficiency is necessary. In this paper, as the next generation BWRs subsequent to ABWRs, the concept of the core of high conversion type BWRs is reported, in which emphasis is placed on the saving of natural uranium resources by raising the rate of conversion to plutonium. This core is that of realizing the high rate of conversion by utilizing the void in the core, which is the feature of BWRs, and the case of making the change of the core structure relatively small by using cross type control rods and the case of changing the core structure for further heightening the rate of conversion and making control rods into cluster type are described. In order to meet the demand like this, Hitachi Ltd. has engaged in the development of the concept of the core of next generation LWRs. In the high conversion type BWRs, there is not large change in the reactor system and turbine system from the current BWRs. The features and the concept of the core of high conversion type BWRs are described. (Kako, I.)

  15. Conversion Factors for Predicting Unshielded Dose Rates in Shielded Waste

    International Nuclear Information System (INIS)

    Clapham, M.; Seamans Jr, J.V.; Arbon, R.E.

    2009-01-01

    This document describes the methodology developed and used by the Advanced Mixed Waste Treatment Project for determining the activity content and the unshielded surface dose rate for lead lined containers contaminated with transuranic waste. Several methods were investigated: - Direct measurement of the dose rate after removing the shielding. - Use of a MicroShield R derived dose conversion factor, (mRem/hr unshielded )/(mRem/hr shielded ), applied to the measured surface dose rate to estimate the unshielded surface dose rate. - Use of a MicroShield R derived activity conversion factor, mRem/hr unshielded /Ci, applied to the measured activity to estimate the unshielded dose rate. - Use of an empirically derived activity conversion factor, mRem/hr unshielded /Ci, applied to the measured activity to estimate the unshielded dose rate. The last approach proved to be the most efficacious by using a combination of nondestructive assay and empirically defined dose rate conversion factors. Empirically derived conversion factors were found to be highly dependent upon the matrix of the waste. Use of conversion factors relied on activity values corrected to address the presence of a lead liner. (authors)

  16. Conversion Rate Optimization : Visual Neuro Programming Principles

    OpenAIRE

    Berezhnaya, Anastasia

    2016-01-01

    The influence of the world wide web has already spread in every business. Consequently, it has become crucial to develop strong online presence and offer qualified user experience for website visitors. Website optimization undeniably has proved its importance in the recent decade. This research was conducted in order to study the practical application and structure of the stages of the CRO (Conversion Rate Optimization) framework that focuses on the most representative website metric – c...

  17. High conversion burner type reactor

    International Nuclear Information System (INIS)

    Higuchi, Shin-ichi; Kawashima, Masatoshi

    1987-01-01

    Purpose: To simply and easily dismantle and reassemble densified fuel assemblies taken out of a high conversion ratio area thereby improve the neutron and fuel economy. Constitution: The burner portion for the purpose of fuel combustion is divided into a first burner region in adjacent with the high conversion ratio area at the center of the reactor core, and a second burner region formed to the outer circumference thereof and two types of fuels are charged therein. Densified fuel assemblies charged in the high conversion ratio area are separatably formed as fuel assemblies for use in the two types of burners. In this way, dense fuel assembly is separated into two types of fuel assemblies for use in burner of different number and arranging density of fuel elements which can be directly charged to the burner portion and facilitate the dismantling and reassembling of the fuel assemblies. Further, since the two types of fuel assemblies are charged in the burner portion, utilization factor for the neutron fuels can be improved. (Kamimura, M.)

  18. High temperature thermoelectric energy conversion

    International Nuclear Information System (INIS)

    Wood, C.

    1986-01-01

    Considerable advances were made in the late '50's and early early '60's in the theory and development of materials for high-temperature thermoelectric energy conversion. This early work culminated in a variety of materials, spanning a range of temperatures, with the product of the figure of merit, Z, and temperature, T, i.e., the dimensionless figure of merit, ZT, of the order of one. This experimental limitation appeared to be universal and led a number of investigators to explore the possibility that a ZT - also represents a theoretical limitation. It was found not to be so

  19. Conversion Rate Optimization through Evolutionary Computation

    OpenAIRE

    Miikkulainen, Risto; Iscoe, Neil; Shagrin, Aaron; Cordell, Ron; Nazari, Sam; Schoolland, Cory; Brundage, Myles; Epstein, Jonathan; Dean, Randy; Lamba, Gurmeet

    2017-01-01

    Conversion optimization means designing a web interface so that as many users as possible take a desired action on it, such as register or purchase. Such design is usually done by hand, testing one change at a time through A/B testing, or a limited number of combinations through multivariate testing, making it possible to evaluate only a small fraction of designs in a vast design space. This paper describes Sentient Ascend, an automatic conversion optimization system that uses evolutionary op...

  20. Improved picture rate conversion using classification based LMS-filters.

    NARCIS (Netherlands)

    An, L.; Heinrich, A.; Cordes, C.N.; Haan, de G.; Rabbani, Majid

    2009-01-01

    Due to the recent explosion of multimedia formats and the need to convert between them, more attention is drawn to picture rate conversion. Moreover, growing demands on video motion portrayal without judder or blur requires improved format conversion. The simplest conversion repeats the latest

  1. 49 CFR 583.14 - Currency conversion rate.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 7 2010-10-01 2010-10-01 false Currency conversion rate. 583.14 Section 583.14... conversion rate. For purposes of calculations of content value under this part, manufacturers and suppliers shall calculate exchange rates using the methodology set forth in this section. (a) Manufacturers. (1...

  2. Performance evaluation of a direct-conversion flat-panel detector system in imaging and quality assurance for a high-dose-rate 192Ir source

    Science.gov (United States)

    Miyahara, Yoshinori; Hara, Yuki; Nakashima, Hiroto; Nishimura, Tomonori; Itakura, Kanae; Inomata, Taisuke; Kitagaki, Hajime

    2018-03-01

    In high-dose-rate (HDR) brachytherapy, a direct-conversion flat-panel detector (d-FPD) clearly depicts a 192Ir source without image halation, even under the emission of high-energy gamma rays. However, it was unknown why iridium is visible when using a d-FPD. The purpose of this study was to clarify the reasons for visibility of the source core based on physical imaging characteristics, including the modulation transfer functions (MTF), noise power spectral (NPS), contrast transfer functions, and linearity of d-FPD to high-energy gamma rays. The acquired data included: x-rays, [X]; gamma rays, [γ] dual rays (X  +  γ), [D], and subtracted data for depicting the source ([D]  -  [γ]). In the quality assurance (QA) test for the positional accuracy of a source core, the coordinates of each dwelling point were compared between the planned and actual source core positions using a CT/MR-compatible ovoid applicator and a Fletcher-Williamson applicator. The profile curves of [X] and ([D]  -  [γ]) matched well on MTF and NPS. The contrast resolutions of [D] and [X] were equivalent. A strongly positive linear correlation was found between the output data of [γ] and source strength (r 2  >  0.99). With regard to the accuracy of the source core position, the largest coordinate difference (3D distance) was noted at the maximum curvature of the CT/MR-compatible ovoid and Fletcher-Williamson applicators, showing 1.74  ±  0.02 mm and 1.01  ±  0.01 mm, respectively. A d-FPD system provides high-quality images of a source, even when high-energy gamma rays are emitted to the detector, and positional accuracy tests with clinical applicators are useful in identifying source positions (source movements) within the applicator for QA.

  3. Mathematical Simulation of High-Conversion Binary Copolymerization

    Institute of Scientific and Technical Information of China (English)

    JiangWei; QinJiguang

    2005-01-01

    A new model for mathematical simulation of high-conversion binary copolymerization was established by combination of the concept of the three stage polymerization model (TSPM) proposed by Qin et al. for bulk free radical homopolymerization with the North equation to describe high-conversion copolymerization reaction exhibiting a strong gel effect, and the mathematical expressions of this new model were derived. Like TSPM, the new model also assmnes that the whole course of binary copolymerization can be divided into three different stages: low conversion, gel effect and glass effect stages. In addition, the reaction rate constants and the initiator efficiency at each copolymerization stage do not vary with conversion. Based on the expressions derived, a plot method for determining the overall rate constants and critical conversions was proposed. The literature data on conversion history for styrene (St)-methyl methacrylate (MMA) and ethylene glycol dimethacrylate (EGDMA)-MMA copolymerizations were treated to examine the model, which shows that the model is satisfactory.

  4. Estimating forest conversion rates with annual forest inventory data

    Science.gov (United States)

    Paul C. Van Deusen; Francis A. Roesch

    2009-01-01

    The rate of land-use conversion from forest to nonforest or natural forest to forest plantation is of interest for forest certification purposes and also as part of the process of assessing forest sustainability. Conversion rates can be estimated from remeasured inventory plots in general, but the emphasis here is on annual inventory data. A new estimator is proposed...

  5. High conversion heavy water moderated reactor

    International Nuclear Information System (INIS)

    Miyawaki, Yoshio; Wakabayashi, Toshio.

    1989-01-01

    In the present invention, fuel rods using uranium-plutonium oxide mixture fuels are arranged in a square lattice at the same pitch as that in light water cooled reactor and heavy water moderators are used. Accordingly, the volume ratio (Vm/Vf) between the moderator and the fuel can be, for example, of about 2. When heavy water is used for the moderator (coolant), since the moderating effect of heavy water is lower than that of light water, a high conversion ratio of not less than 0.8 can be obtained even if the fuel rod arrangement is equal to that of PWR (Vm/Vf about 2). Accordingly, it is possible to avoid problems caused by dense arrangement of fuel rods as in high conversion rate light water cooled reactors. That is, there are no more troubles in view of thermal hydrodynamic characteristics, re-flooding upon loss of coolant accident, etc., as well as the fuel production cost is not increased. (K.M.)

  6. High-conversion emulsion polymerization

    NARCIS (Netherlands)

    Maxwell, I.A.; Verdurmen, E.M.F.J.; German, A.L.

    1992-01-01

    The four important factors that det. the rate of emulsion polymn. are the propagation rate coeff., the latex-particle concn., the monomer concn. in the latex particles, and the free-radical concn. in the latex particles. Both theor. considerations and exptl. evidence suggested that the important

  7. Intelligent Online Marketing : Predicting Conversion Rate Of New Keywords

    OpenAIRE

    Engström, Tommy

    2013-01-01

    This thesis looks at the problem of predicting conversion rate of keywords in Google Adwords where little or no data for the keyword is available. Several methods are investigated and tested on data belonging to three different real world clients. The methods try to predict the conversion rate only given the keyword text. All methods are compared, using two different evaluation methods, with results showing good potential. Finally further improvements are suggested that could have a big impac...

  8. Rate and predictors of conversion from unipolar to bipolar disorder

    DEFF Research Database (Denmark)

    Kessing, Lars Vedel; Willer, Inge; Andersen, Per Kragh

    2017-01-01

    OBJECTIVES: For the first time to present a systematic review and meta-analysis of the conversion rate and predictors of conversion from unipolar disorder to bipolar disorder. METHODS: A systematic literature search up to October 2016 was performed. For the meta-analysis, we only included studies...... that used survival analysis to estimate the conversion rate. RESULTS: A total of 31 studies were identified, among which 11 used survival analyses, including two register-based studies. The yearly rate of conversion to bipolar disorder decreased with time from 3.9% in the first year after study entry...... with a diagnosis of unipolar disorder to 3.1% in years 1-2, 1.0% in years 2-5 and 0.8% in years 5-10. A total of eight risk factors were evaluated comprising gender, age at onset of unipolar disorder, number of depressive episodes, treatment resistance to antidepressants, family history of bipolar disorder...

  9. High conversion HTRs and their fuel cycle

    International Nuclear Information System (INIS)

    Gutmann, H.; Hansen, U.; Larsen, H.; Price, M.S.T.

    1975-01-01

    This report discusses the principles of the core design and the fuel cycle layout for High Conversion HTRs (HCHTRs). Though most of the principles apply equally to HTRs of the pebble-bed and the prismatic fuel element design types, the paper concentrates on the latter. Design and fuel cycle strategies for the full utilisation of the high conversion potential are compared with others that aim at easier reprocessing and the 'environmental' fuel cycle. The paper concludes by discussing operating and fuel cycle characteristics and economics of HCHTRs, and how the latter impinge on the allowable price for uranium ore and the available uranium resources. (orig./UA) [de

  10. Two-Stage Variable Sample-Rate Conversion System

    Science.gov (United States)

    Tkacenko, Andre

    2009-01-01

    A two-stage variable sample-rate conversion (SRC) system has been pro posed as part of a digital signal-processing system in a digital com munication radio receiver that utilizes a variety of data rates. The proposed system would be used as an interface between (1) an analog- todigital converter used in the front end of the receiver to sample an intermediatefrequency signal at a fixed input rate and (2) digita lly implemented tracking loops in subsequent stages that operate at v arious sample rates that are generally lower than the input sample r ate. This Two-Stage System would be capable of converting from an input sample rate to a desired lower output sample rate that could be var iable and not necessarily a rational fraction of the input rate.

  11. Conversion rate for PWR reactors in thorium cycle

    International Nuclear Information System (INIS)

    Angelkorte, G.M.

    1980-01-01

    This work concerns to the determination of the conversion-rate for a PWR reactor with an enrichment of 7.47%, considering a cell, geometrically equal to Angra I, composed by Thorium and U-238 in a 1:1 relation. The study was performed considering neutrons of one and two groups of energy, according to the suggestion from other authors sup(1,2). It was also performed a study about the production and consumption of fissile material. (author)

  12. Lagrangian measurements of sulfur dioxide to sulfate conversion rates

    Energy Technology Data Exchange (ETDEWEB)

    Zak, B D

    1981-12-01

    On the basis of Project MISTT data and proposed homogenous gas phase oxidation mechanisms for sulfur dioxide, it has been suggested that the degree of mixing with background air, the chemical composition of the background air, and the intensity of the sunlight available are key factors determining the rate of sulfur dioxide to sulfate conversion. These hypotheses are examined in light of Lagrangian measrements of conversion rates in power plant plumes made during the Tennessee Plume Study and Project Da Vinci. It is found that the Lagrangian conversion rate measurements are consistent with these hypotheses. It has also been suggested that the concentration of ozone may serve as a workable surrogate for the concentrations of the free radicals involved in the homogeneous gas phase mechanism. The night-time Lagrangian data remind one that the gross difference in mean lifetime of ozone and free radicals can lead to situations in which the ozone concentration is not a good surrogate for the free radical concentrations.

  13. On the equivalence between the minimum entropy generation rate and the maximum conversion rate for a reactive system

    International Nuclear Information System (INIS)

    Bispo, Heleno; Silva, Nilton; Brito, Romildo; Manzi, João

    2013-01-01

    Highlights: • Minimum entropy generation (MEG) principle improved the reaction performance. • MEG rate and the maximum conversion equivalence have been analyzed. • Temperature and residence time are used to the domain establishment of MEG. • Satisfying the temperature and residence time relationship results a optimal performance. - Abstract: The analysis of the equivalence between the minimum entropy generation (MEG) rate and the maximum conversion rate for a reactive system is the main purpose of this paper. While being used as a strategy of optimization, the minimum entropy production was applied to the production of propylene glycol in a Continuous Stirred-Tank Reactor (CSTR) with a view to determining the best operating conditions, and under such conditions, a high conversion rate was found. The effects of the key variables and restrictions on the validity domain of MEG were investigated, which raises issues that are included within a broad discussion. The results from simulations indicate that from the chemical reaction standpoint a maximum conversion rate can be considered as equivalent to MEG. Such a result can be clearly explained by examining the classical Maxwell–Boltzmann distribution, where the molecules of the reactive system under the condition of the MEG rate present a distribution of energy with reduced dispersion resulting in a better quality of collision between molecules with a higher conversion rate

  14. Recent Rates of Forest Harvest and Conversion in North America

    Science.gov (United States)

    Masek, Jeffrey G.; Cohen, Warren B.; Leckie, Donald; Wulder, Michael A.; Vargas, Rodrigo; de Jong, Ben; Healey, Sean; Law, Beverly; Birdsey, Richard; Houghton, R. A.; hide

    2011-01-01

    Incorporating ecological disturbance into biogeochemical models is critical for estimating current and future carbon stocks and fluxes. In particular, anthropogenic disturbances, such as forest conversion and wood harvest, strongly affect forest carbon dynamics within North America. This paper summarizes recent (2000.2008) rates of extraction, including both conversion and harvest, derived from national forest inventories for North America (the United States, Canada, and Mexico). During the 2000s, 6.1 million ha/yr were affected by harvest, another 1.0 million ha/yr were converted to other land uses through gross deforestation, and 0.4 million ha/yr were degraded. Thus about 1.0% of North America fs forests experienced some form of anthropogenic disturbance each year. However, due to harvest recovery, afforestation, and reforestation, the total forest area on the continent has been roughly stable during the decade. On average, about 110 m3 of roundwood volume was extracted per hectare harvested across the continent. Patterns of extraction vary among the three countries, with U.S. and Canadian activity dominated by partial and clear ]cut harvest, respectively, and activity in Mexico dominated by conversion (deforestation) for agriculture. Temporal trends in harvest and clearing may be affected by economic variables, technology, and forest policy decisions. While overall rates of extraction appear fairly stable in all three countries since the 1980s, harvest within the United States has shifted toward the southern United States and away from the Pacific Northwest.

  15. A frequency conversion mode for dispenser in the service station based on flow rate signal

    International Nuclear Information System (INIS)

    Liu, Y J; Tang, D; Huang, J B; Liu, J; Jia, P F

    2012-01-01

    Dispenser is an integrated fuel transport and measurement system at the service station. In this paper, we developed a frequency conversion mode for the dispenser, based on the flow rate signal which is obtained from the converter measuring flow capacity. After introducing the frequency conversion mode to dispenser, we obtained that pump rotates at a high speed when fuelled with high flow rate, and it rotates at a low speed when fuelled with low flow rate. This makes the fuel dispenser more energy-efficient and controllable. We also did some valve optimizations on the dispenser and developed a new control mode for preset refuelling based on the frequency conversion mode, Experimental and theoretical studies have shown that the new dispenser not only can meet the national standards, but also performs better than the ordinary one especially in preset refuelling.

  16. Application of a conversion factor to estimate the adenoma detection rate from the polyp detection rate.

    LENUS (Irish Health Repository)

    Francis, Dawn L

    2011-03-01

    The adenoma detection rate (ADR) is a quality benchmark for colonoscopy. Many practices find it difficult to determine the ADR because it requires a combination of endoscopic and histologic findings. It may be possible to apply a conversion factor to estimate the ADR from the polyp detection rate (PDR).

  17. High population increase rates.

    Science.gov (United States)

    1991-09-01

    In addition to its economic and ethnic difficulties, the USSR faces several pressing demographic problems, including high population increase rates in several of its constituent republics. It has now become clear that although the country's rigid centralized planning succeeded in covering the basic needs of people, it did not lead to welfare growth. Since the 1970s, the Soviet economy has remained sluggish, which as led to increase in the death and birth rates. Furthermore, the ideology that held that demography could be entirely controlled by the country's political and economic system is contradicted by current Soviet reality, which shows that religion and ethnicity also play a significant role in demographic dynamics. Currently, Soviet republics fall under 2 categories--areas with high or low natural population increase rates. Republics with low rates consist of Christian populations (Armenia, Moldavia, Georgia, Byelorussia, Russia, Lithuania, Estonia, Latvia, Ukraine), while republics with high rates are Muslim (Tadzhikistan, Uzbekistan, Turkmenistan, Kirgizia, Azerbaijan Kazakhstan). The later group has natural increase rates as high as 3.3%. Although the USSR as a whole is not considered a developing country, the later group of republics fit the description of the UNFPA's priority list. Another serious demographic issue facing the USSR is its extremely high rate of abortion. This is especially true in the republics of low birth rates, where up to 60% of all pregnancies are terminated by induced abortions. Up to 1/5 of the USSR's annual health care budget is spent on clinical abortions -- money which could be better spent on the production of contraceptives. Along with the recent political and economic changes, the USSR is now eager to deal with its demographic problems.

  18. Advanced high conversion PWR: preliminary analysis

    International Nuclear Information System (INIS)

    Golfier, H.; Bellanger, V.; Bergeron, A.; Dolci, F.; Gastaldi, B.; Koberl, O.; Mignot, G.; Thevenot, C.

    2007-01-01

    In this paper, physical aspects of a HCPWR (High Conversion Light Water Reactor), which is an innovative PWR fuelled with mixed oxide and having a higher conversion ratio due to a lower moderation ratio. Moderation ratios lower than unity are considered which has led to low moderation PWR fuel assembly designs. The objectives of this parametric study are to define a feasibility area with regard to the following neutronic aspects: moderation ratio, Pu loading, reactor spectrum, irradiation time, and neutronic coefficients. Important thermohydraulic parameters are the pressure drop, the critical heat flux, the maximum temperature in the fuel rod and the pumping power. The thermohydraulic analysis shows that a range of moderation ratios from 0.8 to 1.2 is technically possible. A compromise between improved fuel utilization and research and development effort has been found for the moderation ration of about 1. The parametric study shows that there are 2 ranges of interest for the moderation ratio: -) moderation ratio between 0.8 and 1.2 with reduced fissile heights (> 3 m), hexagonal arrangement fuel assembly and square arrangement fuel assembly are possible; and -) moderation between 0.6 and 0.7 with a modification of the reactor operating conditions (reduction of the primary flow and of the thermal power), the fuel rods could be arranged inside a hexagonal fuel rod assembly. (A.C.)

  19. Hospital revisit rate after a diagnosis of conversion disorder.

    Science.gov (United States)

    Merkler, Alexander E; Parikh, Neal S; Chaudhry, Simriti; Chait, Alanna; Allen, Nicole C; Navi, Babak B; Kamel, Hooman

    2016-04-01

    To estimate the hospital revisit rate of patients diagnosed with conversion disorder (CD). Using administrative data, we identified all patients discharged from California, Florida and New York emergency departments (EDs) and acute care hospitals between 2005 and 2011 with a primary discharge diagnosis of CD. Patients discharged with a primary diagnosis of seizure or transient global amnesia (TGA) served as control groups. Our primary outcome was the rate of repeat ED visits and hospital admissions after initial presentation. Poisson regression was used to compare rates between diagnosis groups while adjusting for demographic characteristics. We identified 7946 patients discharged with a primary diagnosis of CD. During a mean follow-up of 3.0 (±1.6) years, patients with CD had a median of three (IQR, 1-9) ED or inpatient revisits, compared with 0 (IQR, 0-2) in patients with TGA and 3 (IQR, 1-7) in those with seizures. Revisit rates were 18.25 (95% CI, 18.10 to 18.40) visits per 100 patients per month in those with CD, 3.90 (95% CI, 3.84 to 3.95) in those with TGA and 17.78 (95% CI, 17.75 to 17.81) in those with seizures. As compared to CD, the incidence rate ratio for repeat ED visits or hospitalisations was 0.89 (95% CI, 0.86 to 0.93) for seizure disorder and 0.32 (95% CI 0.31 to 0.34) for TGA. CD is associated with a substantial hospital revisit rate. Our findings suggest that CD is not an acute, time-limited response to stress, but rather that CD is a manifestation of a broader pattern of chronic neuropsychiatric disease. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  20. A procedure validation for high conversion reactors fuel elements calculation

    International Nuclear Information System (INIS)

    Ishida, V.N.; Patino, N.E.; Abbate, M.J.; Sbaffoni, M.M.

    1990-01-01

    The present work includes procedure validation of cross sections generation starting from nuclear data and the calculation system actually used at the Bariloche Atomic Center Reactor and Neutrons Division for its application to fuel elements calculation of a high conversion reactor (HCR). To this purpose, the fuel element calculation belonging to a High Conversion Boiling water Reactor (HCBWR) was chosen as reference problem, employing the Monte Carlo method. Various cases were considered: with and without control bars, cold of hot, at different vacuum fractions. Multiplication factors, reaction rates, power maps and peak factors were compared. A sensitivity analysis of typical cells used, the approximations employed to solve the transport equation (Sn or Diffusion), the 1-D or 2-D representation and densification of the spatial network used, with the aim of evaluating their influence on the parameters studied and to come to an optimum combination to be used in future design calculations. (Author) [es

  1. 50 CFR Table 3 to Part 679 - Product Recovery Rates for Groundfish Species and Conversion Rates for Pacific Halibut

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Product Recovery Rates for Groundfish Species and Conversion Rates for Pacific Halibut 3 Table 3 to Part 679 Wildlife and Fisheries FISHERY... Rates for Groundfish Species and Conversion Rates for Pacific Halibut ER28JA02.074 ER10JY02.000 ER28JA02...

  2. Parametric study for high conversion pebble bed reactor

    Energy Technology Data Exchange (ETDEWEB)

    Teuchert, E.; Ruetten, H. J.

    1975-06-15

    Tables are presented of fuel cycle costs, conversion ratios and accompanying variations in fuel element designs for a 3,00 MWth high conversion pebble bed reactor with initial high enriched uranium/thorium cycle and subsequent recycling of U-233, Pu-239 and Pu-241.

  3. Derivation of pulse height to exposure rate conversion functions for aerial radiological surveys

    International Nuclear Information System (INIS)

    Artuso, J.F.

    1985-01-01

    A method is described for deriving conversion functions that can be used to convert pulse height spectra taken at altitude to the exposure rate at the 1-m level. An integral equation is set up which involves the integration of a calculated pulse height spectrum multiplied by an unknown conversion function and then set equal to the exposure rate at ground level. This equation is then solved for the conversion function by assuming as a solution a three-term polynomial. Conversion functions have been derived for various source distributions, including surface, uniform, and exponentially distributed sources. These conversion functions are independent of source energy, which means that a conversion can be made without any knowledge of the isotopic content of the source. In the case of a uniform distribution, these conversion functions provide conversions that agree to within 10% with ground truth measurements

  4. Estimates of external dose-rate conversion factors and internal dose conversion factors for selected radionuclides released from fusion facilities

    Energy Technology Data Exchange (ETDEWEB)

    Homma, Toshimitsu; Togawa, Orihiko [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1996-11-01

    This report provides a tabulation of both external dose-rate conversion factors and internal dose conversion factors using radioactive decay data in the updated Evaluated Nuclear Structure Data File (ENSDF) for selected 26 radionuclides and all their daughter radionuclides of potential importance in safety assessments of fusion facilities. The external dose-rate conversion factors for 21 target organs are tabulated for three exposure modes that are immersion in contaminated air, irradiation at a height of 1 m above a contaminated ground surface and immersion contaminated water. For internal exposure, committed dose equivalents, based on the methodology of ICRP Publication 30, in the same target organs per intake of unit activity are given for the inhalation and ingestion exposure pathways. The data presented here is intended to be generally used for safety assessments of fusion reactors. Comparisons of external effective dose-rate conversion factors and committed effective dose equivalents are made with the previous data from the independent data bases to provide quality assurance on our calculated results. There is generally good agreement among data from the independent data bases. The differences in the values of both effective dose-rate and dose conversion factors appeared are primarily due to differences in calculational methodology, the use of different radioactive decay data, and compilation errors. (author)

  5. Optimization of mass flow rate in RGTT200K coolant purification for Carbon Monoxide conversion process

    International Nuclear Information System (INIS)

    Sumijanto; Sriyono

    2016-01-01

    Carbon monoxide is a species that is difficult to be separated from the reactor coolant helium because it has a relatively small molecular size. So it needs a process of conversion from carbon monoxide to carbondioxide. The rate of conversion of carbon monoxide in the purification system is influenced by several parameters including concentration, temperature and mass flow rate. In this research, optimization of the mass flow rate in coolant purification of RGTT200K for carbon monoxide conversion process was done. Optimization is carried out by using software Super Pro Designer. The rate of reduction of reactant species, the growth rate between the species and the species products in the conversion reactions equilibrium were analyzed to derive the mass flow rate optimization of purification for carbon monoxide conversion process. The purpose of this study is to find the mass flow rate of purification for the preparation of the basic design of the RGTT200K coolant helium purification system. The analysis showed that the helium mass flow rate of 0.6 kg/second resulted in an un optimal conversion process. The optimal conversion process was reached at a mass flow rate of 1.2 kg/second. A flow rate of 3.6 kg/second – 12 kg/second resulted in an ineffective process. For supporting the basic design of the RGTT200K helium purification system, the mass flow rate for carbon monoxide conversion process is suggested to be 1.2 kg/second. (author)

  6. Performance analysis of 60-min to 1-min integration time rain rate conversion models in Malaysia

    Science.gov (United States)

    Ng, Yun-Yann; Singh, Mandeep Singh Jit; Thiruchelvam, Vinesh

    2018-01-01

    Utilizing the frequency band above 10 GHz is in focus nowadays as a result of the fast expansion of radio communication systems in Malaysia. However, rain fade is the critical factor in attenuation of signal propagation for frequencies above 10 GHz. Malaysia is located in a tropical and equatorial region with high rain intensity throughout the year, and this study will review rain distribution and evaluate the performance of 60-min to 1-min integration time rain rate conversion methods for Malaysia. Several conversion methods such as Segal, Chebil & Rahman, Burgeono, Emiliani, Lavergnat and Gole (LG), Simplified Moupfouma, Joo et al., fourth order polynomial fit and logarithmic model have been chosen to evaluate the performance to predict 1-min rain rate for 10 sites in Malaysia. After the completion of this research, the results show that Chebil & Rahman model, Lavergnat & Gole model, Fourth order polynomial fit and Logarithmic model have shown the best performances in 60-min to 1-min rain rate conversion over 10 sites. In conclusion, it is proven that there is no single model which can claim to perform the best across 10 sites. By averaging RMSE and SC-RMSE over 10 sites, Chebil and Rahman model is the best method.

  7. Comparison of the two different standard flux-to-dose rate conversion factors

    International Nuclear Information System (INIS)

    Metghalchi, M.; Ashrafi, R.

    1983-01-01

    A very useful and simple way of obtaining the dose rate associated with neutron or photon fluxes is to multiply these fluxes by the appropriate flux-to-dose rate conversion factors. Two basic standard flux-to-dose rate conversion factors. are being used in all over the world, those recommended by the International Commission on Radiation Protection (ICRP) and the American National Standars (ANS). The purpose of this paper is to compare these two standard with each other. The comparison proved that the dose rate associated with a specific neutron flux, obtained by the ANS flux-to-dose rate conversion factors is usually higher than those calculated by the ICRP's conversion factors. Whereas in the case of the photon, in all energies, the difference between the dose rates obtained by these two standard flux-to-dose rate conversion factors are noticeable, and the ANS results are higher than the ICRP ones. So, it should be noted that for a specific neutron or photon flux the dose rate obtained by the ANS flux-to-dose rate conversion factors are more conservative than those obtained by the ICRP's. Therefore, in order to establish a more reasonable new standard flux-to-dose rate conversion factors, more work should be done. (author)

  8. Surgical volume and conversion rate in laparoscopic hysterectomy: does volume matter? A multicenter retrospective cohort study.

    Science.gov (United States)

    Keurentjes, José H M; Briët, Justine M; de Bock, Geertruida H; Mourits, Marian J E

    2018-02-01

    A multicenter, retrospective, cohort study was conducted in the Netherlands. The aim was to evaluate whether surgical volume of laparoscopic hysterectomies (LHs) performed by proven skilled gynecologists had an impact on the conversion rate from laparoscopy to laparotomy. In 14 hospitals, all LHs performed by 19 proven skilled gynecologists between 2007 and 2010 were included in the analysis. Surgical volume, conversion rate and type of conversion (reactive or strategic) were retrospectively assessed. To estimate the impact of surgical volume on the conversion rate, logistic regressions were performed. These regressions were adjusted for patient's age, Body Mass Index (BMI), ASA classification, previous abdominal surgery and the indication (malignant versus benign) for the LH. During the study period, 19 proven skilled gynecologists performed a total of 1051 LHs. Forty percent of the gynecologists performed over 20 LHs per year (median 17.3, range 5.4-49.5). Conversion to laparotomy occurred in 5.0% of all LHs (53 of 1051); 38 (3.6%) were strategic and 15 (1.4%) were reactive conversions. Performing over 20 LHs per year was significantly associated with a lower overall conversion rate (OR adjusted 0.43, 95% CI 0.24-0.77), a lower strategic conversion rate (OR adjusted 0.32, 95% CI 0.16-0.65), but not with a lower reactive conversion rate (OR adjusted 0.96, 95% CI 0.33-2.79). A higher annual surgical volume of LHs by proven skilled gynecologists is inversely related to the conversion rate to laparotomy, and results in a lower strategic conversion rate.

  9. Conversion factors for estimating release rate of gaseous radioactivity by an aerial survey

    International Nuclear Information System (INIS)

    Saito, Kimiaki; Moriuchi, Shigeru

    1988-02-01

    Conversion factors necessary for estimating release rate of gaseous radioactivity by an aerial survey are presented. The conversion factors were determined based on calculation assuming a Gaussian plume model as a function of atmospheric stability, down-wind distance and flight height. First, the conversion factors for plumes emitting mono-energy gamma rays were calculated, then, conversion factors were constructed through convolution for the radionuclides essential in an accident of a nuclear reactor, and for mixtures of these radionuclides considering elapsed time after shutdown. These conversion factors are shown in figures, and also polynomial expressions of the conversion factors as a function of height have been decided with the least-squares method. A user can easily obtain proper conversion factors from data shown here. (author)

  10. Conversion of highly active waste to solids

    International Nuclear Information System (INIS)

    Scheffler, K.

    Borosilicate glasses were selected as matrix material for solidification of highly radioactive wastes. Current laboratory work on the VERA process is described. Goals were met by a five-component glass VG-38 and a glass-ceramic VC-15. The VERA process is described: flowsheet, denitration, calcinator, fusion facility

  11. High-conversion HTRs and their fuel cycle

    International Nuclear Information System (INIS)

    Gutmann, H.; Hansen, U.; Larsen, H.; Price, M.S.T.

    1976-01-01

    The high-temperature reactors using graphite as structural core material and helium as coolant represent thermal reactor designs with a very high degree of neutron economy which, when using the thorium fuel cycle, offer, at least theoretically, the possibility of thermal breeding. Though this was already known from previous studies, the economic climate at that time was such that the achievement of high conversion ratios conflicted with the incentive for low fuel cycle costs. Consequently, thorium cycle conversion ratios of around 0.6 were found optimum, and the core and fuel element layout followed from the economic ground rules. The recent change in attitude, brought about partly by the slow process of realization of the limits to the earth's accessible high-grade uranium ore resources and more dramatically by the oil crisis, makes it necessary to concentrate attention again on the high conversion fuel cycles. This report discusses the principles of the core design and the fuel cycle layout for High Conversion HTRs (HCHTRs). Though most of the principles apply equally to HTRs of the pebble-bed and the prismatic fuel element design types, the paper concentrates on the latter. Design and fuel cycle strategies for the full utilization of the high conversion potential are compared with others that aim at easier reprocessing and the ''environmental'' fuel cycle. The paper concludes by discussing operating and fuel cycle characteristics and economics of HCHTRs, and how the latter impinge on the allowable price for uranium ore and the available uranium resources. (author)

  12. The determinants of conversion rates in SME e-commerce websites

    OpenAIRE

    Di Fatta, D.; Patton, Dean; Viglia, G.

    2018-01-01

    © 2017 Web retailers invest significant resources to improve the proportion of website visitors that make a purchase, also known as the conversion rate. Improving this rate is particularly important to SMEs that have traditionally lagged behind larger firms as they have found it difficult to justify the significant investment involved in website development against the historical low returns associated with an online sales channel. Identifying methods that increase conversion rates reduces th...

  13. DIGITAL FLOOD INSURANCE RATE MAP DATABASE, CONVERSE COUNTY, WYOMING, USA.

    Data.gov (United States)

    Federal Emergency Management Agency, Department of Homeland Security — The Digital Flood Insurance Rate Map (DFIRM) Database depicts flood risk information and supporting data used to develop the risk data. The primary risk...

  14. Advances in Very High Frequency Power Conversion

    DEFF Research Database (Denmark)

    Kovacevic, Milovan

    Resonant and quasi-resonant converters operated at frequencies above 30 MHz have attracted special attention in the last two decades. Compared to conventional converters operated at ~100 kHz, they offer significant advantages: smaller volume and weight, lower cost, and faster transient performance....... Excellent performance and small size of magnetic components and capacitors at very high frequencies, along with constant advances in performance of power semiconductor devices, suggests a sizable shift in consumer power supplies market into this area in the near future. To operate dc-dc converter power...... method provides low complexity and low gate loss simultaneously. A direct design synthesis method is provided for resonant SEPIC converters employing this technique. Most experimental prototypes were developed using low cost, commercially available power semiconductors. Due to very fast transient...

  15. Temporal dynamics of high repetition rate pulsed single longitudinal ...

    Indian Academy of Sciences (India)

    ing (GIG) cavity, single-mode dye laser pumped by high repetition rate ... in a high loss cavity, a detailed theoretical study and optimization of cavity ..... rate for high conversion efficiency and longer pulse width of the single-mode dye laser.

  16. Oscillating thermionic conversion for high-density space power

    International Nuclear Information System (INIS)

    Jacobson, D.L.; Morris, J.F.

    1988-01-01

    The compactness, maneuverability, and productive weight utilization of space nuclear reactors benefit from the use of thermionic converters at high temperature. Nuclear-thermionic-conversion power requirements are discussed, and the role of oscillations in thermionic energy conversion (TEC) history is examined. Proposed TEC oscillations are addressed, and the results of recent studies of TEC oscillations are reviewed. The possible use of high-frequency TEC oscillations to amplify low-frequency ones is considered. The accomplishments of various programs studying the use of high-temperature thermionic oscillators are examined. 16 references

  17. Solutions for ultra-high speed optical wavelength conversion and clock recovery

    DEFF Research Database (Denmark)

    Oxenløwe, Leif Katsuo; Galili, Michael; Mulvad, Hans Christian Hansen

    2006-01-01

    This paper reports on our recent advances in ultra-fast optical communications relying on ultra-short pulses densely stacked in ultra-high bit rate serial data signals at a single wavelength. The paper describes details in solutions for the network functionalities of wavelength conversion and clock...... recovery at bit rates up to 320 Gb/s...

  18. Calculation of dose-rate conversion factors for external exposure to photons and electrons

    International Nuclear Information System (INIS)

    Kocher, D.C.

    1978-01-01

    Methods are presented for the calculation of dose-rate conversion factors for external exposure to photon and electron radiation from radioactive decay. A dose-rate conversion factor is defined as the dose-equivalent rate per unit radionuclide concentration. Exposure modes considered are immersion in contaminated air, immersion in contaminated water, and irradiation from a contaminated ground surface. For each radiation type and exposure mode, dose-rate conversion factors are derived for tissue-equivalent material at the body surface of an exposed individual. In addition, photon dose-rate conversion factors are estimated for 22 body organs. The calculations are based on the assumption that the exposure medium is infinite in extent and that the radionuclide concentration is uniform. The dose-rate conversion factors for immersion in contaminated air and water then follow from the requirement that all of the energy emitted in the radioactive decay is absorbed in the infinite medium. Dose-rate conversion factors for ground-surface exposure are calculated at a reference location above a smooth, infinite plane using the point-kernel integration method and known specific absorbed fractions for photons and electrons in air

  19. External dose-rate conversion factors for calculation of dose to the public

    Energy Technology Data Exchange (ETDEWEB)

    1988-07-01

    This report presents a tabulation of dose-rate conversion factors for external exposure to photons and electrons emitted by radionuclides in the environment. This report was prepared in conjunction with criteria for limiting dose equivalents to members of the public from operations of the US Department of Energy (DOE). The dose-rate conversion factors are provided for use by the DOE and its contractors in performing calculations of external dose equivalents to members of the public. The dose-rate conversion factors for external exposure to photons and electrons presented in this report are based on a methodology developed at Oak Ridge National Laboratory. However, some adjustments of the previously documented methodology have been made in obtaining the dose-rate conversion factors in this report. 42 refs., 1 fig., 4 tabs.

  20. High Rate Digital Demodulator ASIC

    Science.gov (United States)

    Ghuman, Parminder; Sheikh, Salman; Koubek, Steve; Hoy, Scott; Gray, Andrew

    1998-01-01

    The architecture of High Rate (600 Mega-bits per second) Digital Demodulator (HRDD) ASIC capable of demodulating BPSK and QPSK modulated data is presented in this paper. The advantages of all-digital processing include increased flexibility and reliability with reduced reproduction costs. Conventional serial digital processing would require high processing rates necessitating a hardware implementation in other than CMOS technology such as Gallium Arsenide (GaAs) which has high cost and power requirements. It is more desirable to use CMOS technology with its lower power requirements and higher gate density. However, digital demodulation of high data rates in CMOS requires parallel algorithms to process the sampled data at a rate lower than the data rate. The parallel processing algorithms described here were developed jointly by NASA's Goddard Space Flight Center (GSFC) and the Jet Propulsion Laboratory (JPL). The resulting all-digital receiver has the capability to demodulate BPSK, QPSK, OQPSK, and DQPSK at data rates in excess of 300 Mega-bits per second (Mbps) per channel. This paper will provide an overview of the parallel architecture and features of the HRDR ASIC. In addition, this paper will provide an over-view of the implementation of the hardware architectures used to create flexibility over conventional high rate analog or hybrid receivers. This flexibility includes a wide range of data rates, modulation schemes, and operating environments. In conclusion it will be shown how this high rate digital demodulator can be used with an off-the-shelf A/D and a flexible analog front end, both of which are numerically computer controlled, to produce a very flexible, low cost high rate digital receiver.

  1. Framing the conversation: use of PRECIS-2 ratings to advance understanding of pragmatic trial design domains.

    Science.gov (United States)

    Lipman, Paula Darby; Loudon, Kirsty; Dluzak, Leanora; Moloney, Rachael; Messner, Donna; Stoney, Catherine M

    2017-11-10

    There continues to be debate about what constitutes a pragmatic trial and how it is distinguished from more traditional explanatory trials. The NIH Pragmatic Trials Collaborative Project, which includes five trials and a coordinating unit, has adopted the Pragmatic-Explanatory Continuum Indicator Summary (PRECIS-2) instrument. The purpose of the study was to collect PRECIS-2 ratings at two points in time to assess whether the tool was sensitive to change in trial design, and to explore with investigators the rationale for rating shifts. A mixed-methods design included sequential collection and analysis of quantitative data (PRECIS-2 ratings) and qualitative data. Ratings were collected at two annual, in-person project meetings, and subsequent interviews conducted with investigators were recorded, transcribed, and coded using NVivo 11 Pro for Windows. Rating shifts were coded as either (1) actual change (reflects a change in procedure or protocol), (2) primarily a rating shift reflecting rater variability, or (3) themes that reflect important concepts about the tool and/or pragmatic trial design. Based on PRECIS-2 ratings, each trial was highly pragmatic at the planning phase and remained so 1 year later in the early phases of trial implementation. Over half of the 45 paired ratings for the nine PRECIS-2 domains indicated a rating change from Time 1 to Time 2 (N = 24, 53%). Of the 24 rating changes, only three represented a true change in the design of the trial. Analysis of rationales for rating shifts identified critical themes associated with the tool or pragmatic trial design more generally. Each trial contributed one or more relevant comments, with Eligibility, Flexibility of Adherence, and Follow-up each accounting for more than one. PRECIS-2 has proved useful for "framing the conversation" about trial design among members of the Pragmatic Trials Collaborative Project. Our findings suggest that design elements assessed by the PRECIS-2 tool may represent

  2. All-optical wavelength conversion at bit rates above 10 Gb/s using semiconductor optical amplifiers

    DEFF Research Database (Denmark)

    Jørgensen, Carsten; Danielsen, Søren Lykke; Stubkjær, Kristian

    1997-01-01

    This work assesses the prospects for high-speed all-optical wavelength conversion using the simple optical interaction with the gain in semiconductor optical amplifiers (SOAs) via the interband carrier recombination. Operation and design guidelines for conversion speeds above 10 Gb/s are described...... and the various tradeoffs are discussed. Experiments at bit rates up to 40 Gb/s are presented for both cross-gain modulation (XGM) and cross-phase modulation (XPM) in SOAs demonstrating the high-speed capability of these techniques...

  3. Mechanical Conversion for High-Throughput TEM Sample Preparation

    International Nuclear Information System (INIS)

    Kendrick, Anthony B; Moore, Thomas M; Zaykova-Feldman, Lyudmila

    2006-01-01

    This paper presents a novel method of direct mechanical conversion from lift-out sample to TEM sample holder. The lift-out sample is prepared in the FIB using the in-situ liftout Total Release TM method. The mechanical conversion is conducted using a mechanical press and one of a variety of TEM coupons, including coupons for both top-side and back-side thinning. The press joins a probe tip point with attached TEM sample to the sample coupon and separates the complete assembly as a 3mm diameter TEM grid, compatible with commercially available TEM sample holder rods. This mechanical conversion process lends itself well to the high through-put requirements of in-line process control and to materials characterization labs where instrument utilization and sample security are critically important

  4. Meiotic gene-conversion rate and tract length variation in the human genome.

    Science.gov (United States)

    Padhukasahasram, Badri; Rannala, Bruce

    2013-02-27

    Meiotic recombination occurs in the form of two different mechanisms called crossing-over and gene-conversion and both processes have an important role in shaping genetic variation in populations. Although variation in crossing-over rates has been studied extensively using sperm-typing experiments, pedigree studies and population genetic approaches, our knowledge of variation in gene-conversion parameters (ie, rates and mean tract lengths) remains far from complete. To explore variability in population gene-conversion rates and its relationship to crossing-over rate variation patterns, we have developed and validated using coalescent simulations a comprehensive Bayesian full-likelihood method that can jointly infer crossing-over and gene-conversion rates as well as tract lengths from population genomic data under general variable rate models with recombination hotspots. Here, we apply this new method to SNP data from multiple human populations and attempt to characterize for the first time the fine-scale variation in gene-conversion parameters along the human genome. We find that the estimated ratio of gene-conversion to crossing-over rates varies considerably across genomic regions as well as between populations. However, there is a great degree of uncertainty associated with such estimates. We also find substantial evidence for variation in the mean conversion tract length. The estimated tract lengths did not show any negative relationship with the local heterozygosity levels in our analysis.European Journal of Human Genetics advance online publication, 27 February 2013; doi:10.1038/ejhg.2013.30.

  5. Present status and subjects of research on heat removal in high conversion light water reactors

    International Nuclear Information System (INIS)

    Murao, Yoshio

    1990-01-01

    Merits of high conversion LWRs: (1) The utilization of nuclear fuel several times as much as that in LWRs is possible. The rate of effective utilization of uranium is 4-6%. (2) The active storage of plutonium is feasible. (3) The bridging to the nuclear fuel cycle industries in fast reactor age can be done. (4) These contribute to the control of plutonium storage as the partner of FBRs in fast reactor age. (5) These contribute to the flexibility of medium and long term energy strategy. The reduction of natural uranium demand by the introduction of high conversion LWRs: Assuming the scale of nuclear power facilities in 2030 as 107 million kW, and that HCLWRs are introduced from 2000, the reduction till 2100 is 13%. The features of high conversion LWRs, the effect of improving the conversion ratio by spectral hardening and so on are explained. The specification of high conversion LWRs is shown in comparison with other reactor types. The aim is the high conversion PWRs in which the same safety as conventional LWRs is ensured, and energy resources and economical efficiency are attractive. The schedule of the research and the subjects of the thermo-hydraulic engineering research are shown. (K.I.)

  6. Burnup calculation in microcells of high conversion reactors

    International Nuclear Information System (INIS)

    Gomez, S.E.; Salvatore, M.; Patino, N.E.; Abbate, M.J.

    1991-01-01

    The development of high converter reactors (HCR) requires careful burnup calculations because their main goals are reach high discharge burnup levels (Up to 50 GWd/T) and a close to one conversion ratio. Then, it is necessary a revision of design elements used for this type of calculation. In this work, a burnup module (BUM) developed in order to use nuclear data directly from evaluated data files is presented; these was included in the AMPX system. (author)

  7. Lepton flavour violating μ-e conversion rate for various nuclei

    International Nuclear Information System (INIS)

    Koike, Masafumi; Kitano, Ryuichiro; Okada, Yasuhiro

    2003-01-01

    The coherent μ-e conversion rate for general LFV interactions for various nuclei is calculated. The branching ratio increases for the light nuclei such as Z ∼ 60. Although this tendency of Z dependence is the same for different types of coupling constants, there are significant differences in Z dependence of branching ratios. The atomic number dependence of the conversion ratio calculated here is useful to distinguish theoretical models with lepton flavour violation

  8. The fitting parameters extraction of conversion model of the low dose rate effect in bipolar devices

    International Nuclear Information System (INIS)

    Bakerenkov, Alexander

    2011-01-01

    The Enhanced Low Dose Rate Sensitivity (ELDRS) in bipolar devices consists of in base current degradation of NPN and PNP transistors increase as the dose rate is decreased. As a result of almost 20-year studying, the some physical models of effect are developed, being described in detail. Accelerated test methods, based on these models use in standards. The conversion model of the effect, that allows to describe the inverse S-shaped excess base current dependence versus dose rate, was proposed. This paper presents the problem of conversion model fitting parameters extraction.

  9. High conversion pressurized water reactor with boiling channels

    Energy Technology Data Exchange (ETDEWEB)

    Margulis, M., E-mail: maratm@post.bgu.ac.il [The Unit of Nuclear Engineering, Ben Gurion University of the Negev, POB 653, Beer Sheva 84105 (Israel); Shwageraus, E., E-mail: es607@cam.ac.uk [Department of Engineering, University of Cambridge, CB2 1PZ Cambridge (United Kingdom)

    2015-10-15

    Highlights: • Conceptual design of partially boiling PWR core was proposed and studied. • Self-sustainable Th–{sup 233}U fuel cycle was utilized in this study. • Seed-blanket fuel assembly lattice optimization was performed. • A coupled Monte Carlo, fuel depletion and thermal-hydraulics studies were carried out. • Thermal–hydraulic analysis assured that the design matches imposed safety constraints. - Abstract: Parametric studies have been performed on a seed-blanket Th–{sup 233}U fuel configuration in a pressurized water reactor (PWR) with boiling channels to achieve high conversion ratio. Previous studies on seed-blanket concepts suggested substantial reduction in the core power density is needed in order to operate under nominal PWR system conditions. Boiling flow regime in the seed region allows more heat to be removed for a given coolant mass flow rate, which in turn, may potentially allow increasing the power density of the core. In addition, reduced moderation improves the breeding performance. A two-dimensional design optimization study was carried out with BOXER and SERPENT codes in order to determine the most attractive fuel assembly configuration that would ensure breeding. Effects of various parameters, such as void fraction, blanket fuel form, number of seed pins and their dimensions, on the conversion ratio were examined. The obtained results, for which the power density was set to be 104 W/cm{sup 3}, created a map of potentially feasible designs. It was found that several options have the potential to achieve end of life fissile inventory ratio above unity, which implies potential feasibility of a self-sustainable Thorium fuel cycle in PWRs without significant reduction in the core power density. Finally, a preliminary three-dimensional coupled neutronic and thermal–hydraulic analysis for a single seed-blanket fuel assembly was performed. The results indicate that axial void distribution changes drastically with burnup. Therefore

  10. Improved conversion rates in drug screening applications using miniaturized electrochemical cells with frit channels.

    Science.gov (United States)

    Odijk, Mathieu; Olthuis, Wouter; van den Berg, A; Qiao, Liang; Girault, Hubert

    2012-11-06

    This paper reports a novel design of a miniaturized three-electrode electrochemical cell, the purpose of which is aimed at generating drug metabolites with a high conversion efficiency. The working electrode and the counter electrode are placed in two separate channels to isolate the reaction products generated at both electrodes. The novel design includes connecting channels between these two electrode channels to provide a uniform distribution of the current density over the entire working electrode. In addition, the effect of ohmic drop is decreased. Moreover, two flow resistors are included to ensure an equal flow of analyte through both electrode channels. Total conversion of fast reacting ions is achieved at flow rates up to at least 8 μL/min, while the internal chip volume is only 175 nL. Using this electrochemical chip, the metabolism of mitoxantrone is studied by microchip electrospray ionization-mass spectrometry. At an oxidation potential of 700 mV, all known metabolites from direct oxidation are observed. The electrochemical chip performs equally well, compared to a commercially available cell, but at a 30-fold lower flow of reagents.

  11. Frequency conversion of high-intensity, femtosecond laser pulses

    Energy Technology Data Exchange (ETDEWEB)

    Banks, P S

    1997-06-01

    Almost since the invention of the laser, frequency conversion of optical pulses via non- linear processes has been an area of active interest. However, third harmonic generation using ~(~1 (THG) in solids is an area that has not received much attention because of ma- terial damage limits. Recently, the short, high-intensity pulses possible with chirped-pulse amplification (CPA) laser systems allow the use of intensities on the order of 1 TW/cm2 in thin solids without damage. As a light source to examine single-crystal THG in solids and other high field inter- actions, the design and construction of a Ti:sapphire-based CPA laser system capable of ultimately producing peak powers of 100 TW is presented. Of special interest is a novel, all-reflective pulse stretcher design which can stretch a pulse temporally by a factor of 20,000. The stretcher design can also compensate for the added material dispersion due to propagation through the amplifier chain and produce transform-limited 45 fs pulses upon compression. A series of laser-pumped amplifiers brings the peak power up to the terawatt level at 10 Hz, and the design calls for additional amplifiers to bring the power level to the 100 TW level for single shot operation. The theory for frequency conversion of these short pulses is presented, focusing on conversion to the third harmonic in single crystals of BBO, KD*P, and d-LAP (deuterated I-arginine phosphate). Conversion efficiencies of up to 6% are obtained with 500 fs pulses at 1053 nm in a 3 mm thick BBO crystal at 200 GW/cm 2. Contributions to this process by unphasematched, cascaded second harmonic generation and sum frequency generation are shown to be very significant. The angular relationship between the two orders is used to measure the tensor elements of C = xt3)/4 with Crs = -1.8 x 1O-23 m2/V2 and .15Cri + .54Crs = 4.0 x 1O-23 m2/V2. Conversion efficiency in d-LAP is about 20% that in BBO and conversion efficiency in KD*P is 1% that of BBO. It is calculated

  12. Fiber Bragg grating based notch filter for bit-rate-transparent NRZ to PRZ format conversion with two-degree-of-freedom optimization

    International Nuclear Information System (INIS)

    Cao, Hui; Zuo, Jun; Xiong, Bangyun; Cheng, Jianqun; Shu, Xuewen; Shen, Fangcheng; Liu, Xin; Atai, Javid

    2015-01-01

    We propose a novel notch-filtering scheme for bit-rate transparent all-optical NRZ-to-PRZ format conversion. The scheme is based on a two-degree-of-freedom optimally designed fiber Bragg grating. It is shown that a notch filter optimized for any specific operating bit rate can be used to realize high-Q-factor format conversion over a wide bit rate range without requiring any tuning. (paper)

  13. High enrichment to low enrichment core's conversion. Technical securities

    International Nuclear Information System (INIS)

    Abbate, P.; Madariaga, M.R.

    1990-01-01

    This work presents the fulfillment of the technical securities subscribed by INVAP S.E. for the conversion of a high enriched uranium core. The reactor (of 5 thermal Mw), built in the 50's and 60's, is of the 'swimming pool' type, with light water and fuel elements of the curve plates MTR type, enriched at 93.15 %. These are neutronic and thermohydraulic securities. (Author) [es

  14. Calculation of neutron and gamma-ray flux-to-dose-rate conversion factors

    International Nuclear Information System (INIS)

    Kwon, S.G.; Lee, S.Y.; Yook, C.C.

    1981-01-01

    This paper presents flux-to-dose-rate conversion factors for neutrons and gamma rays based on the American National Standard Institute (ANSI) N666. These data are used to calculate the dose rate distribution of neutron and gamma ray in radiation fields. Neutron flux-to-dose-rate conversion factors for energies from 2.5 x 10 -8 to 20 MeV are presented; the corresponding energy range for gamma rays is 0.01 to 15 MeV. Flux-to-dose-rate conversion factors were calculated, under the assumption that radiation energy distribution has nonlinearity in the phantom, have different meaning from those values obtained by monoenergetic radiation. Especially, these values were determined with the cross section library. The flux-to-dose-rate conversion factors obtained in this work were in a good agreement to the values presented by ANSI. Those data will be useful for the radiation shielding analysis and the radiation dosimetry in the case of continuous energy distributions. (author)

  15. High conversion ratio plutonium recycle in pressurized water reactors

    International Nuclear Information System (INIS)

    Edlund, M.C.

    1975-01-01

    The use of Pu light water reactors in such a way as to minimise the depletion of Pu needed for future use, and therefore to reduce projected demands for U ore and U enrichment is envisaged. Fuel utilisation in PWRs could be improved by tightly-packed fuel rod lattices with conversion ratios of 0.8 to 0.9 compared with ratios of about 0.5 in Pu recycle designs using fuel to water volume ratios of currently operating PWRs. A conceptual design for the Babcock and Wilcox Company reactors now in operation is presented and for illustrative purposes thermalhydraulic design considerations and the reactor physics are described. Principle considerations in the mechanical design of the fuel assemblies are the effect of hydraulic forces, thermal expansion, and fission gas release. The impact of high conversion ratio plutionium recycle in separative work and natural U requirements for PWRs likely to be in operation by 1985 are examined. (U.K.)

  16. Towards a default soil carbon sequestration rate after cropland to Miscanthus conversion in Europe

    Science.gov (United States)

    Poeplau, Christopher; Don, Axel

    2013-04-01

    In Europe, an estimated 17-21 million hectares (Mha) of land will need to be converted to bioenergy crop production to meet the EU bioenergy targets for 2020. Conventional bioenergy crops, such as maize and oilseed rape, are known for high greenhouse gas emissions. Perennial grases, such as Miscanthus, are seen as sustainable alternative, due to low fertilizer demand, relatively high yields and the potential to sequester soil organic carbon (SOC). However, the variability of currently published SOC stock changes is huge, ranging from -6.8 to +7.7 Mg ha-1 yr-1, which we attribute to different organic manure applications and differences in the baseline SOC stocks between the sampled plots in the paired plot approach. The conversion from cropland to Miscanthus involves a C3-C4 vegetation change, which allows following the incorporation of C4 Miscanthus-derived carbon into the soil by measuring the abundance of the stable isotope 13C. This was done for six different Miscanthus plantations across Europe, which were older than ten years. C3 carbon decomposition was estimated using the carbon turnover model RothC. Both, C4 and C3 carbon dynamics were summed to obtain the vegetation change-induced SOC stock change. We subsequently applied this approach to all European sites, where C4 carbon dynamic after cropland to Miscanthus conversion has been investigated (n=14) and derived a temperature dependant SOC sequestration rate. We found a mean annual accumulation of 0.40±0.20 Mg C ha-1. Furthermore, we conducted a SOC fractionation to assess the incorporation of C4 carbon into different SOC fractions. After a mean time of 16 years, the particulate organic matter (POM) fraction consisted of 68% Miscanthus-derived carbon in 0-10 cm soil depth. The NaOCl resistant fraction, which is considered "inert", consisted of 12% Miscanthus-derived carbon in 0-10 cm soil depth.

  17. All passive architecture for high efficiency cascaded Raman conversion

    Science.gov (United States)

    Balaswamy, V.; Arun, S.; Chayran, G.; Supradeepa, V. R.

    2018-02-01

    Cascaded Raman fiber lasers have offered a convenient method to obtain scalable, high-power sources at various wavelength regions inaccessible with rare-earth doped fiber lasers. A limitation previously was the reduced efficiency of these lasers. Recently, new architectures have been proposed to enhance efficiency, but this came at the cost of enhanced complexity, requiring an additional low-power, cascaded Raman laser. In this work, we overcome this with a new, all-passive architecture for high-efficiency cascaded Raman conversion. We demonstrate our architecture with a fifth-order cascaded Raman converter from 1117nm to 1480nm with output power of ~64W and efficiency of 60%.

  18. Optimization of hierarchical 3DRS motion estimators for picture rate conversion

    NARCIS (Netherlands)

    Heinrich, A.; Bartels, C.L.L.; Vleuten, van der R.J.; Cordes, C.N.; Haan, de G.

    2010-01-01

    There is a continuous pressure to lower the implementation complexity and improve the quality of motion-compensated picture rate conversion methods. Since the concept of hierarchy can be advantageously applied to many motion estimation methods, we have extended and improved the current

  19. Ultra-high-speed wavelength conversion in a silicon photonic chip

    DEFF Research Database (Denmark)

    Hu, Hao; Ji, Hua; Galili, Michael

    2011-01-01

    We have successfully demonstrated all-optical wavelength conversion of a 640-Gbit/s line-rate return-to-zero differential phase-shift keying (RZ-DPSK) signal based on low-power four wave mixing (FWM) in a silicon photonic chip with a switching energy of only ~110 fJ/bit. The waveguide dispersion...... of the silicon nanowire is nano-engineered to optimize phase matching for FWM and the switching power used for the signal processing is low enough to reduce nonlinear absorption from twophoton- absorption (TPA). These results demonstrate that high-speed wavelength conversion is achievable in silicon chips...

  20. Vitamin C supplementation improve the sputum conversion culture rate in pulmonary tuberculosis treatment while rifampicin susceptible

    Science.gov (United States)

    Susanto, L.; Siregar, Y.; Kusumawati, L.

    2018-03-01

    The failure of first-line tuberculosis treatment greatly affects multiple drug-resistant tuberculosis. In vitro study of vitamin C induces the death of M. tuberculosis bacteria and accelerates healing of tuberculosis, so the multiple drug-resistant tuberculosis can be avoided. This research aimed to identify the effect of vitamin C as a supportive treatment on the sputum conversion rate. The randomizedand double group with a parallel design by matching pair method was used to collect samples. The first group was treated with standard tuberculosis treatment, and the other was given vitamin C supplementation. Vitamin C plasma level analyzation was performed before and after two months of treatment. Sputum conversion was evaluated every week for eight weeks. The comparison of vitamin C plasma level in pre and post-treatment group was significant (p=0.03) but not in the other group. There was no significant difference in vitamin C plasma level between two groups (p=0.21). The proportion of sputum conversion rate in both group in the first week was 0% vs. 9.6% (p=0.83) and the last week of study was 83.9% vs. 100% (p=0.02). In conclusion, vitamin C supplementation has effects in improving the healing process of tuberculosis patients as indicated by higher in sputum conversion rate.

  1. High enrichment to low enrichment core's conversion. Accidents analysis

    International Nuclear Information System (INIS)

    Abbate, P.; Rubio, R.; Doval, A.; Lovotti, O.

    1990-01-01

    This work analyzes the different accidents that may occur in the reactor's facility after the 20% high-enriched uranium core's conversion. The reactor (of 5 thermal Mw), built in the 50's and 60's, is of the 'swimming pool' type, with light water and fuel elements of the curve plates MTR type, enriched at 93.15 %. This analysis includes: a) accidents by reactivity insertion; b) accidents by coolant loss; c) analysis by flow loss and d) fission products release. (Author) [es

  2. Electrohydrodynamics: a high-voltage direct energy conversion process

    International Nuclear Information System (INIS)

    Brun, S.

    1967-04-01

    This analysis consists of a theoretical and practical study of a high-tension electrical power generator based on the Van de Graaff generator principle, the main difference being that the charges produced are transported by a gas in motion and not by a belt. The electrical and thermal properties of such a generator are studied, as well as the difficult problem of the production of the ionised particles used in the conversion. A certain number of results already published on this process for converting kinetic energy into electrical energy is given, as well as some possible applications in the field of space technology. (author) [fr

  3. Scaling the energy conversion rate from magnetic field reconnection to different bodies

    International Nuclear Information System (INIS)

    Mozer, F. S.; Hull, A.

    2010-01-01

    Magnetic field reconnection is often invoked to explain electromagnetic energy conversion in planetary magnetospheres, stellar coronae, and other astrophysical objects. Because of the huge dynamic range of magnetic fields in these bodies, it is important to understand energy conversion as a function of magnetic field strength and related parameters. It is conjectured theoretically and shown experimentally that the energy conversion rate per unit area in reconnection scales as the cube of an appropriately weighted magnetic field strength divided by the square root of an appropriately weighted density. With this functional dependence, the energy release in flares on the Sun, the large and rapid variation of the magnetic flux in the tail of Mercury, and the apparent absence of reconnection on Jupiter and Saturn, may be understood. Electric fields at the perihelion of the Solar Probe Plus mission may be tens of V/m.

  4. [Improving the feed conversion rate in the pig fattening industry by optimising hygienic management].

    Science.gov (United States)

    Riedl, Antonia M; Völkel, Inger; Schlindwein, Bernhard; Czerny, Claus-Peter

    2013-01-01

    Considering continuously increasing forage costs, the feed conversion rate has a major impact on the economic efficiency in hog fattening. The influence of hygienic management strategies on animal health and feed efficiency was evaluated by an online-study comprising animal health management data of 202 German pig fatteners. Data analysis included a simple comparison of averages, a linear regression analysis, and a cluster analysis. Due to geographical distribution and size of premises, the random sample was not representative but yielded in significant results. The total impact of hygienic management on feed conversion was calculated to be 23.9 %. Professional performance of rodent control (beta = 0.357; p conversion ranged from Euro 1.15 to and Euro 2.53 per pig. Likewise optimized growth performance as a result of improved hygienic management could partly compensate increasing feed costs. The results of this online-study reveal the need to establish reliable HACCP systems on farm level.

  5. Rapid assessment of malaria transmission using age-specific sero-conversion rates.

    Directory of Open Access Journals (Sweden)

    Laveta Stewart

    2009-06-01

    Full Text Available Malaria transmission intensity is a crucial determinant of malarial disease burden and its measurement can help to define health priorities. Rapid, local estimates of transmission are required to focus resources better but current entomological and parasitological methods for estimating transmission intensity are limited in this respect. An alternative is determination of antimalarial antibody age-specific sero-prevalence to estimate sero-conversion rates (SCR, which have been shown to correlate with transmission intensity. This study evaluated SCR generated from samples collected from health facility attendees as a tool for a rapid assessment of malaria transmission intensity.The study was conducted in north east Tanzania. Antibodies to Plasmodium falciparum merozoite antigens MSP-1(19 and AMA-1 were measured by indirect ELISA. Age-specific antibody prevalence was analysed using a catalytic conversion model based on maximum likelihood to generate SCR. A pilot study, conducted near Moshi, found SCRs for AMA-1 were highly comparable between samples collected from individuals in a conventional cross-sectional survey and those collected from attendees at a local health facility. For the main study, 3885 individuals attending village health facilities in Korogwe and Same districts were recruited. Both malaria parasite prevalence and sero-positivity were higher in Korogwe than in Same. MSP-1(19 and AMA-1 SCR rates for Korogwe villages ranged from 0.03 to 0.06 and 0.07 to 0.21 respectively. In Same district there was evidence of a recent reduction in transmission, with SCR among those born since 1998 [MSP-1(19 0.002 to 0.008 and AMA-1 0.005 to 0.014 ] being 5 to 10 fold lower than among individuals born prior to 1998 [MSP-1(19 0.02 to 0.04 and AMA-1 0.04 to 0.13]. Current health facility specific estimates of SCR showed good correlations with malaria incidence rates in infants in a contemporaneous clinical trial (MSP-1(19 r(2 = 0.78, p<0.01 & AMA-1 r

  6. Rates and Predictors of Conversion to Schizophrenia or Bipolar Disorder Following Substance-Induced Psychosis.

    Science.gov (United States)

    Starzer, Marie Stefanie Kejser; Nordentoft, Merete; Hjorthøj, Carsten

    2018-04-01

    The authors investigated the rates of conversion to schizophrenia and bipolar disorder after a substance-induced psychosis, as well as risk factors for conversion. All patient information was extracted from the Danish Civil Registration System and the Psychiatric Central Research Register. The study population included all persons who received a diagnosis of substance-induced psychosis between 1994 and 2014 (N=6,788); patients were followed until first occurrence of schizophrenia or bipolar disorder or until death, emigration, or August 2014. The Kaplan-Meier method was used to obtain cumulative probabilities for the conversion from a substance-induced psychosis to schizophrenia or bipolar disorder. Cox proportional hazards regression models were used to calculate hazard ratios for all covariates. Overall, 32.2% (95% CI=29.7-34.9) of patients with a substance-induced psychosis converted to either bipolar or schizophrenia-spectrum disorders. The highest conversion rate was found for cannabis-induced psychosis, with 47.4% (95% CI=42.7-52.3) converting to either schizophrenia or bipolar disorder. Young age was associated with a higher risk of converting to schizophrenia. Self-harm after a substance-induced psychosis was significantly linked to a higher risk of converting to both schizophrenia and bipolar disorder. Half the cases of conversion to schizophrenia occurred within 3.1 years after a substance-induced psychosis, and half the cases of conversion to bipolar disorder occurred within 4.4 years. Substance-induced psychosis is strongly associated with the development of severe mental illness, and a long follow-up period is needed to identify the majority of cases.

  7. High efficiency heat transport and power conversion system for cascade

    International Nuclear Information System (INIS)

    Maya, I.; Bourque, R.F.; Creedon, R.L.; Schultz, K.R.

    1985-02-01

    The Cascade ICF reactor features a flowing blanket of solid BeO and LiAlO 2 granules with very high temperature capability (up to approx. 2300 K). The authors present here the design of a high temperature granule transport and heat exchange system, and two options for high efficiency power conversion. The centrifugal-throw transport system uses the peripheral speed imparted to the granules by the rotating chamber to effect granule transport and requires no additional equipment. The heat exchanger design is a vacuum heat transfer concept utilizing gravity-induced flow of the granules over ceramic heat exchange surfaces. A reference Brayton power cycle is presented which achieves 55% net efficiency with 1300 K peak helium temperature. A modified Field steam cycle (a hybrid Rankine/Brayton cycle) is presented as an alternate which achieves 56% net efficiency

  8. Improved Conversion Rates in Drug Screening Applications sing Miniaturized Electrochemical Cells with Frit Channels

    NARCIS (Netherlands)

    Odijk, Mathieu; Olthuis, Wouter; van den Berg, Albert; Qiao, L.; Girault, H.

    2012-01-01

    This paper reports a novel design of a miniaturized three-electrode electrochemical cell, the purpose of which is aimed at generating drug metabolites with a high conversion efficiency. The working electrode and the counter electrode are placed in two separate channels to isolate the reaction

  9. Power Conversion Study for High Temperature Gas-Cooled Reactors

    International Nuclear Information System (INIS)

    Chang Oh; Richard Moore; Robert Barner

    2005-01-01

    The Idaho National Laboratory (INL) is investigating a Brayton cycle efficiency improvement on a high temperature gas-cooled reactor (HTGR) as part of Generation-IV nuclear engineering research initiative. There are some technical issues to be resolved before the selection of the final design of the high temperature gas cooled reactor, called as a Next Generation Nuclear Plant (NGNP), which is supposed to be built at the INEEL by year 2017. The technical issues are the selection of the working fluid, direct vs. indirect cycle, power cycle type, the optimized design in terms of a number of intercoolers, and others. In this paper, we investigated a number of working fluids for the power conversion loop, direct versus indirect cycle, the effect of intercoolers, and other thermal hydraulics issues. However, in this paper, we present part of the results we have obtained. HYSYS computer code was used along with a computer model developed using Visual Basic computer language

  10. Modeling of the reactant conversion rate in a turbulent shear flow

    Science.gov (United States)

    Frankel, S. H.; Madnia, C. K.; Givi, P.

    1992-01-01

    Results are presented of direct numerical simulations (DNS) of spatially developing shear flows under the influence of infinitely fast chemical reactions of the type A + B yields Products. The simulation results are used to construct the compositional structure of the scalar field in a statistical manner. The results of this statistical analysis indicate that the use of a Beta density for the probability density function (PDF) of an appropriate Shvab-Zeldovich mixture fraction provides a very good estimate of the limiting bounds of the reactant conversion rate within the shear layer. This provides a strong justification for the implementation of this density in practical modeling of non-homogeneous turbulent reacting flows. However, the validity of the model cannot be generalized for predictions of higher order statistical quantities. A closed form analytical expression is presented for predicting the maximum rate of reactant conversion in non-homogeneous reacting turbulence.

  11. Influence of curing rate on softening in ethanol, degree of conversion, and wear of resin composite

    DEFF Research Database (Denmark)

    Benetti, Ana Raquel; Peutzfeldt, Anne; Asmussen, Erik

    2011-01-01

    PURPOSE: To investigate the effect of curing rate on softening in ethanol, degree of conversion, and wear of resin composites. METHOD: With a given energy density and for each of two different light-curing units (QTH or LED), the curing rate was reduced by modulating the curing mode. Thus......, the irradiation of resin composite specimens (Filtek Z250, Tetric Ceram, Esthet-X) was performed in a continuous curing mode and in a pulse-delay curing mode. Wallace hardness was used to determine the softening of resin composite after storage in ethanol. Degree of conversion was determined by infrared...... exposed to the pulse-delay curing mode were softer than resin composites exposed to continuous cure (Pconversion (P

  12. Improper ferroelectrics as high-efficiency energy conversion materials

    Energy Technology Data Exchange (ETDEWEB)

    Wakamatsu, Toru; Tanabe, Kenji; Terasaki, Ichiro; Taniguchi, Hiroki [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan)

    2017-05-15

    An improper ferroelectric is a certain type of ferroelectrics whose primary order parameter is not polarization but another physical quantity such as magnetization. In contrast to a conventional proper ferroelectrics as represented by Pb(Zr,Ti)O{sub 3} and BaTiO{sub 3}, the improper ferroelectrics has been inconceivable for practical applications thus far. Herein, we illustrate the great potential of improper ferroelectrics for efficient conversion of temperature fluctuation to electric energy, as demonstrated with (Ca{sub 0.84}Sr{sub 0.16}){sub 8}[AlO{sub 2}]{sub 12}(MoO{sub 4}){sub 2} (CSAM-16). The present study has experimentally proven that CSAM-16 achieves an excellent electrothermal coupling factor and high electric field sensitivity for pyroelectric energy conversion that approach a practical level for application to self-powered autonomous electronic devices for rapidly spreading wireless sensor networks. The present results provide a novel approach to developing innovative pyroelectric energy harvesting devices using improper ferroelectrics. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Improper ferroelectrics as high-efficiency energy conversion materials

    International Nuclear Information System (INIS)

    Wakamatsu, Toru; Tanabe, Kenji; Terasaki, Ichiro; Taniguchi, Hiroki

    2017-01-01

    An improper ferroelectric is a certain type of ferroelectrics whose primary order parameter is not polarization but another physical quantity such as magnetization. In contrast to a conventional proper ferroelectrics as represented by Pb(Zr,Ti)O_3 and BaTiO_3, the improper ferroelectrics has been inconceivable for practical applications thus far. Herein, we illustrate the great potential of improper ferroelectrics for efficient conversion of temperature fluctuation to electric energy, as demonstrated with (Ca_0_._8_4Sr_0_._1_6)_8[AlO_2]_1_2(MoO_4)_2 (CSAM-16). The present study has experimentally proven that CSAM-16 achieves an excellent electrothermal coupling factor and high electric field sensitivity for pyroelectric energy conversion that approach a practical level for application to self-powered autonomous electronic devices for rapidly spreading wireless sensor networks. The present results provide a novel approach to developing innovative pyroelectric energy harvesting devices using improper ferroelectrics. (copyright 2017 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Low Power High Dynamic Range A/D Conversion Channel

    DEFF Research Database (Denmark)

    Marker-Villumsen, Niels; Rombach, Pirmin

    in the conversion channel in order to avoid distortion for large input signals. In combination with a low resolution A/D converter (ADC) and a digital gain block, the adaptive A/D conversion channel achieves an extended dynamic range beyond that of the ADC. This in turn reduces the current consumption......This work concerns the analysis of an adaptive analog-to-digital (A/D) conversion channel for use with a micro electromechanical system (MEMS) microphone for audio applications. The adaptive A/D conversion channel uses an automatic gain control (AGC) for adjusting the analog preamplifier gain...... of the conversion channel in comparison to a static A/D conversion channel; this at the cost of a reduced peak signal-to-noise ratio (SNR). The adaptive A/D conversion channel compensates for the change in analog gain by a digital gain, thus achieving a constant channel gain in the full dynamic range. However...

  15. Optimization of hierarchical 3DRS motion estimators for picture rate conversion

    OpenAIRE

    Heinrich, A.; Bartels, C.L.L.; Vleuten, van der, R.J.; Cordes, C.N.; Haan, de, G.

    2010-01-01

    There is a continuous pressure to lower the implementation complexity and improve the quality of motion-compensated picture rate conversion methods. Since the concept of hierarchy can be advantageously applied to many motion estimation methods, we have extended and improved the current state-of-the-art motion estimation method in this field, 3-Dimensional Recursive Search (3DRS), with this concept. We have explored the extensive parameter space and present an analysis of the importance and in...

  16. Monitoring forest/non-forest land use conversion rates with annual inventory data

    Science.gov (United States)

    Francis A. Roesch; Paul C. Van Deusen

    2012-01-01

    The transitioning of land from forest to other uses is of increasing interest as urban areas expand and the world’s population continues to grow. Also of interest, but less recognized, is the transitioning of land from other uses into forest. In this paper, we show how rates of conversion from forest to non-forest and non-forest to forest can be estimated in the US...

  17. Process and catalysts for hydrocarbon conversion. [high antiknock motor fuel

    Energy Technology Data Exchange (ETDEWEB)

    1940-02-14

    High anti-knock motor fuel is produced from hydrocarbons by subjecting it at an elevated temperature to contact with a calcined mixture of hydrated silica, hydrated alumina, and hydrated zirconia, substantially free from alkali metal compounds. The catalyst may be prepared by precipitating silica gel by the acidification of an aqueous solution of an alkali metal silicate, intimately mixing hydrated alumina and hydrated zirconia therewith, drying, purifying the composite to substantially remove alkali metal compounds, again drying, forming the dried material into particles, and finally calcining. The resultant conversion products may be fractionated to produce gasoline, hydrocarbon oil above gasoling boiling point range, and a gaseous fraction of olefins which are polymerized into gasoline boiling range polymers.

  18. Conceptual design study of high conversion light water reactor

    International Nuclear Information System (INIS)

    Okumura, Keisuke; Akie, Hiroshi; Mori, Takamasa; Nakagawa, Masayuki; Ishiguro, Yukio

    1990-06-01

    Since 1984, R and D work has been made for high conversion light water reactors (HCLWRs), at JAERI, to improve the natural uranium saving and effective plutonium utilization by the use of conventional or extended LWR technology. This report summarizes the results of the feasibility study made mainly from the viewpoint of nuclear design in the Phase-I Program (1985∼1989). Until now, the following various types of HCLWR core concepts have been investigated; 1) homogeneous core with tight pitch lattice of fuel rods, 2) homogeneous core with semi-tight pitch lattice, 3) spectral shift core using fertile rod with semi-tight pitch lattice, 4) flat-core, 5) axial heterogeneous core. The core burnup and thermohydraulic analyses during normal operations have been performed to clear up the burnup performances and feasibility for each core. Based on the analysis results, the axial heterogeneous HCLWR core was selected as the JAERI reference core. (author)

  19. On the muon-nucleus integrals entering the neutrinoless μ- → e- conversion rates

    International Nuclear Information System (INIS)

    Kosmas, T S; Lagaris, I E

    2002-01-01

    The muon-nucleus integrals which determine the nuclear-structure dependence of the branching ratio R μe , i.e. the rate of the flavour-changing muon-electron conversion divided by the total rate of the ordinary muon capture, are extensively studied. Precise muon wavefunctions are employed which are obtained by solving the Schroedinger and Dirac equations. To this aim a method based on modern neural network techniques is developed which gives the radial muon wavefunctions as a linear combination of sigmoid functions

  20. Kinetic modeling of ethane pyrolysis at high conversion.

    Science.gov (United States)

    Xu, Chen; Al Shoaibi, Ahmed Sultan; Wang, Chenguang; Carstensen, Hans-Heinrich; Dean, Anthony M

    2011-09-29

    The primary objective of this study is to develop an improved first-principle-based mechanism that describes the molecular weight growth kinetics observed during ethane pyrolysis. A proper characterization of the kinetics of ethane pyrolysis is a prerequisite for any analysis of hydrocarbon pyrolysis and oxidation. Flow reactor experiments were performed with ~50/50 ethane/nitrogen mixtures with temperatures ranging from 550 to 850 °C at an absolute pressure of ~0.8 atm and a residence time of ~5 s. These conditions result in ethane conversions ranging from virtually no reaction to ~90%. Comparisons of predictions using our original mechanism to these data yielded very satisfactory results in terms of the temperature dependence of ethane conversion and prediction of the major products ethylene and hydrogen. However, there were discrepancies in some of the minor species concentrations that are involved in the molecular weight growth kinetics. We performed a series of CBS-QB3 analyses for the C(3)H(7), C(4)H(7), and C(4)H(9) potential energy surfaces to better characterize the radical addition reactions that lead to molecular weight growth. We also extended a published C(6)H(9) PES to include addition of vinyl to butadiene. The results were then used to calculate pressure-dependent rate constants for the multiple reaction pathways of these addition reactions. Inclusion of the unadjusted rate constants resulting from these analyses in the mechanism significantly improved the description of several of the species involved in molecular weight growth kinetics. We compare the predictions of this improved model to those obtained with a consensus model recently published as well as to ethane steam cracking data. We find that a particularly important reaction is that of vinyl addition to butadiene. Another important observation is that several radical addition reactions are partially equilibrated. Not only does this mean that reliable thermodynamic parameters are essential

  1. Implementation elements for conversion of general-purpose freeway lane into high-occupancy-vehicle lane

    Science.gov (United States)

    1997-01-01

    Conversion of a general-purpose freeway into a high-occupancy-vehicle (HOV) lane is an alternative to infrastructure addition for HOV system implementation. Research indicates that lane conversion is feasible technically if sufficient HOV usage and m...

  2. Continuum random-phase approximation study of the incoherent μ--e- conversion rate and its spurious 1- admixture

    International Nuclear Information System (INIS)

    Papakonstantinou, P.; Wambach, J.; Kosmas, T.S.; Faessler, A.

    2006-01-01

    The incoherent transition strength of the exotic μ - -e - conversion in the 208 Pb nucleus is investigated by utilizing the continuum random-phase-approximation method, appropriate for the evaluation of the rate that goes to the continuum of the nuclear spectrum. We find that the contribution of resonances lying high in the continuum is not negligible. Special attention is paid to the detailed study of the pronounced 1 - contribution that according to previous calculations, dominates the overall incoherent rate in about all the nuclear targets. The spurious center-of-mass admixture to the partial rate originating from the 1 - excitations is explored, and its elimination is performed by correcting properly the dipole operators. The results found this way show that the greatest portion of the total 1 - contribution to the incoherent rate is spurious

  3. Bit-rate-transparent optical RZ-to-NRZ format conversion based on linear spectral phase filtering

    DEFF Research Database (Denmark)

    Maram, Reza; Da Ros, Francesco; Guan, Pengyu

    2017-01-01

    We propose a novel and strikingly simple design for all-optical bit-rate-transparent RZ-to-NRZ conversion based on optical phase filtering. The proposed concept is experimentally validated through format conversion of a 640 Gbit/s coherent RZ signal to NRZ signal.......We propose a novel and strikingly simple design for all-optical bit-rate-transparent RZ-to-NRZ conversion based on optical phase filtering. The proposed concept is experimentally validated through format conversion of a 640 Gbit/s coherent RZ signal to NRZ signal....

  4. High-fidelity frequency down-conversion of visible entangled photon pairs with superconducting single-photon detectors

    International Nuclear Information System (INIS)

    Ikuta, Rikizo; Kato, Hiroshi; Kusaka, Yoshiaki; Yamamoto, Takashi; Imoto, Nobuyuki; Miki, Shigehito; Yamashita, Taro; Terai, Hirotaka; Wang, Zhen; Fujiwara, Mikio; Sasaki, Masahide; Koashi, Masato

    2014-01-01

    We experimentally demonstrate a high-fidelity visible-to-telecommunicationwavelength conversion of a photon by using a solid-state-based difference frequency generation. In the experiment, one half of a pico-second visible entangled photon pair at 780 nm is converted to a 1522-nm photon. Using superconducting single-photon detectors with low dark count rates and small timing jitters, we observed a fidelity of 0.93±0.04 after the wavelength conversion

  5. Low-temperature conversion of high-moisture biomass: Topical report, January 1984--January 1988

    Energy Technology Data Exchange (ETDEWEB)

    Sealock, L.J. Jr.; Elliott, D.C.; Butner, R.S.; Neuenschwander, G.G.

    1988-10-01

    Pacific Northwest Laboratory (PNL) is developing a low-temperature, catalytic process that converts high-moisture biomass feedstocks and other wet organic substances to useful gaseous and liquid fuels. The advantage of this process is that it works without the need for drying or dewatering the feedstock. Conventional thermal gasification processes, which require temperatures above 750/degree/C and air or oxygen for combustion to supply reaction heat, generally cannot utilize feedstocks with moisture contents above 50 wt %, as the conversion efficiency is greatly reduced as a result of the drying step. For this reason, anaerobic digestion or other bioconversion processes traditionally have been used for gasification of high-moisture feedstocks. However, these processes suffer from slow reaction rates and incomplete carbon conversion. 50 refs., 21 figs., 22 tabs.

  6. Nitric oxide-to-nitrogen dioxide conversion rates at a natural gas compressor station

    International Nuclear Information System (INIS)

    Gibbons, T.H.; Gebhart, D.H.

    1992-01-01

    An ambient air quality measurements program collected NO x data for a year at a natural gas compressor station located in the southwestern United States. This monitoring program had the unique characteristic of measuring ambient NO x concentrations at a remote location that was virtually free of NO sources other than the compressor station. These measurements indicate that the only source of NO x emissions in the area comes from the combustion of natural gas by the compressor station turbines. Thus, increases in NO 2 calculation of NO-to-NO 2 conversion rates. These results indicate 22 percent of the compressor station NO x emissions were converted to NO 2 in the near field. Regulatory modeling methods often assume that all NO x emissions exist as NO 2 . In an environment where ozone concentrations are relatively low, however, NO 2 concentrations are commonly calculated using the ozone limiting method (OLM), wherein NO conversion to NO 2 is limited by the amount of ozone present. Results from the measurement program show that the OLM generally overpredicts NO 2 concentrations in the near field. A partial conversion method is more suitable for predicting NO 2 concentrations for low-level natural gas combustion sources

  7. Leadership conversations challenging high potential managers to become great leaders

    CERN Document Server

    Berson, Alan S

    2012-01-01

    Conversation techniques and tools that can help strong managers become great leaders Often the very same skills and traits that enable rising stars to achieve success ""tenacity, aggressiveness, self-confidence"" become liabilities when promoted into a leadership track. While managers'' conversations are generally transactional and centered on the task at hand, leaders must focus on people, asking great questions and aligning them with the vision for the future. Leadership mindsets and skills can be developed, and Leadership Conversations provides practical guidance for connecting with others

  8. Ortho-para conversion in the solid hydrogens at high pressures

    International Nuclear Information System (INIS)

    Strzhemechny; Hemley, R.J.

    2003-01-01

    At low pressures the ortho-para conversion in H 2 and D 2 is a slow process governed by the magnetic dipole interaction of nuclear magnetic moments, phonons being the main energy sink. As the pressure is raised to a few GPa and the Debye temperature increases substantially, the conversion energy finds itself in an area where phonon states are depleted and conversion slows down. The recent Raman and NMR experiments showed that the conversion rate in H 2 after an initial slowdown predicted by theory increases immensely. As for solid D 2 , conversion rates have apparently not yet been directly measured under pressure. In order to explain the anomaly observed in H 2 , we have suggested a new conversion mechanism, in which the basic conversion-producing interaction only initiates conversion whereas the energy is removed by rotational excitations via the stronger electric quadrupole-quadrupole interaction. Estimated conversion rates are in good qualitative agreement with available experimental observations. Here we extend the theory to solid D 2 taking into account the differences between H 2 and D 2 in the molecular and solid-state parameters. The new libron-mediated channel is predicted to result for D 2 in conversion rates under pressure that are by an order of magnitude larger than at P = 0

  9. Internal conversion coefficients of high multipole transitions: Experiment and theories

    International Nuclear Information System (INIS)

    Gerl, J.; Vijay Sai, K.; Sainath, M.; Gowrishankar, R.; Venkataramaniah, K.

    2008-01-01

    A compilation of the available experimental internal conversion coefficients (ICCs), α T , α K , α L , and ratios K/L and K/LM of high multipole (L > 2) transitions for a number of elements in the range 21 ≤ Z ≤ 94 is presented. Our listing of experimental data includes 194 data sets on 110 E3 transitions, 10 data sets on 6 E4 transitions, 11 data sets on 7 E5 transitions, 38 data sets on 21 M3 transitions, and 132 data sets on 68 M4 transitions. Data with less than 10% experimental uncertainty have been selected for comparison with the theoretical values of Hager and Seltzer [R.S. Hager, E.C. Seltzer, Nucl. Data Tables A 4 (1968) 1], Rosel et al. [F. Roesel, H.M. Fries, K. Alder, H.C. Pauli, At. Data Nucl. Data Tables 21 (1978) 91], and BRICC. The relative percentage deviations (%Δ) have been calculated for each of the above theories and the averages (%Δ-bar) are estimated. The Band et al. [I.M. Band, M.B. Trzhaskovskaya, C.W. Nestor Jr., P.O. Tikkanen, S. Raman, At. Data Nucl. Data Tables 81 (2002) 1] tables, using the BRICC interpolation code, are seen to give theoretical ICCs closest to experimental values

  10. Lignin conversion to high-octane fuel additives

    Energy Technology Data Exchange (ETDEWEB)

    Shabtai, J.; Zmierczak, W.; Kadangode, S. [University of Utah, Salt Lake City (United States); Chornet, E.; Johnson, D.K. [National Renewable Energy Laboratory, Golden, CO (United States)

    1999-07-01

    Continuing previous studies on the conversion of lignin to reformulated gasoline compositions, new lignin upgrading processes were developed that allow preferential production of specific high-octane fuel additives of two distinct types: (1) C{sub 7}-C{sub 10} alkylbenzenes; and (2) aryl methyl ethers, where aryl mostly = phenyl, 2-methylphenyl, 4-methylphenyl, and dimethylphenyl. Process (1) comprises base-catalyzed depolymerization (BCD) and simultaneous partial ({approx} 50%) deoxygenation of lignin at 270 - 290{sup o}C, in the presence of supercritical methanol as reaction medium, followed by exhaustive hydrodeoxygenation and attendant mild hydrocracking of the BCD product with sulfided catalysts to yield C{sub 8}-C{sub 10} alkylbenzenes as main products. Process (2) involves mild BCD at 250 - 270{sup o}C with preservation of the lignin oxygen, followed by selective C-C hydrocracking with solid superacid catalysts. This method preferentially yields a mixture of alkylated phenols, which upon acid-catalyzed etherification with methanol are converted into corresponding aryl methyl ethers (see above) possessing blending octane numbers in the range of 142-166. In a recent extension of this work, a greatly advantageous procedure for performing the BCD stage of processes (1) and (2) in water as reaction medium was developed. (author)

  11. High-Resolution Measurements of Low-Energy Conversion Electrons

    CERN Multimedia

    Gizon, A; Putaux, J

    2002-01-01

    Measurements of low-energy internal conversion electrons have been performed with high energy resolution in some N = 105 odd and odd-odd nuclei using a semi-circular spectrograph associated to a specific tape transport system. These experiments aimed to answer the following questions~: \\begin{itemize} \\item Do M3 isomeric transitions exist in $^{183}$Pt and $^{181}$Os, isotones of $^{184}$Au~? \\item Are the neutron configurations proposed to describe the isomeric and ground states of $^{184}$Au right or wrong~? \\item Does it exist an isomeric state in $^{182}$Ir, isotone of $^{181}$Os, $^{183}$Pt and $^{184}$Au~? \\item What are the spin and parity values of the excited states of $^{182}$Ir~? \\end{itemize} In $^{183}$Pt, the 35.0 keV M3 isomeric transition has been clearly observed and the reduced transition probability has been determined. The deduced hindrance factor is close to that observed in the neighbouring odd-odd $^{184}$Au nucleus. This confirms the neutron configurations previously proposed for the ...

  12. High-order harmonic conversion efficiency in helium

    International Nuclear Information System (INIS)

    Crane, J.K.

    1992-01-01

    Calculated results are presented for the energy, number of photons, and conversion efficiency for high-order harmonic generation in helium. The results show the maximum values that we should expect to achieve experimentally with our current apparatus and the important parameters for scaling this source to higher output. In the desired operating regime where the coherence length, given by L coh =πb/(q-1), is greater than the gas column length, l, the harmonic output can be summarized by a single equation: N q =[(π z n z b 3 τ q |d q | z )/4h]{(p/q)(2l/b) z }. N q - numbers of photons of q-th harmonic; n - atom density; b - laser confocal parameter; τ q - pulse width of harmonic radiation; q - harmonic order; p - effective order of nonlinearity. (Note the term in brackets, the phase-matching function, has been separated from the rest of the expression in order to be consistent with the relevant literature)

  13. High efficiency Dual-Cycle Conversion System using Kr-85.

    Science.gov (United States)

    Prelas, Mark A; Tchouaso, Modeste Tchakoua

    2018-04-26

    This paper discusses the use of one of the safest isotopes known isotopes, Kr-85, as a candidate fuel source for deep space missions. This isotope comes from 0.286% of fission events. There is a vast quantity of Kr-85 stored in spent fuel and it is continually being produced by nuclear reactors. In using Kr-85 with a novel Dual Cycle Conversion System (DCCS) it is feasible to boost the system efficiency from 26% to 45% over a single cycle device while only increasing the system mass by less than 1%. The Kr-85 isotope is the ideal fuel for a Photon Intermediate Direct Energy Conversion (PIDEC) system. PIDEC is an excellent choice for the top cycle in a DCCS. In the top cycle, ionization and excitation of the Kr-85:Cl gas mixture (99% Kr and 1% Cl) from beta particles creates KrCl* excimer photons which are efficiently absorbed by diamond photovoltaic cells on the walls of the pressure vessels. The benefit of using the DCCS is that Kr-85 is capable of operating at high temperatures in the primary cycle and the residual heat can then be converted into electrical power in the bottom cycle which uses a Stirling Engine. The design of the DCCS begins with a spherical pressure vessel of radius 13.7 cm with 3.7 cm thick walls and is filled with a Kr-85:Cl gas mixture. The inner wall has diamond photovoltaic cells attached to it and there is a sapphire window between the diamond photovoltaic cells and the Kr-85:Cl gas mixture which shields the photovoltaic cells from beta particles. The DCCS without a gamma ray shield has specific power of 6.49 W/kg. A removable 6 cm thick tungsten shield is used to safely limit the radiation exposure levels of personnel. A shadow shield remains in the payload to protect the radiation sensitive components in the flight package. The estimated specific power of the unoptimized system design in this paper is about 2.33 W/kg. The specific power of an optimized system should be higher. The Kr-85 isotope is relatively safe because it

  14. Consensus Through Conversation How to Achieve High-Commitment Decisions

    CERN Document Server

    Dressler, Larry

    2006-01-01

    Facilitation expert Larry Dressler's Consensus Through Conversation is a guide for the effective facilitation and practice of one of business's most popular - but most widely misunderstood - decision-making models: consensus.

  15. Small protease sensitive oligomers of PrPSc in distinct human prions determine conversion rate of PrP(C.

    Directory of Open Access Journals (Sweden)

    Chae Kim

    Full Text Available The mammalian prions replicate by converting cellular prion protein (PrP(C into pathogenic conformational isoform (PrP(Sc. Variations in prions, which cause different disease phenotypes, are referred to as strains. The mechanism of high-fidelity replication of prion strains in the absence of nucleic acid remains unsolved. We investigated the impact of different conformational characteristics of PrP(Sc on conversion of PrP(C in vitro using PrP(Sc seeds from the most frequent human prion disease worldwide, the Creutzfeldt-Jakob disease (sCJD. The conversion potency of a broad spectrum of distinct sCJD prions was governed by the level, conformation, and stability of small oligomers of the protease-sensitive (s PrP(Sc. The smallest most potent prions present in sCJD brains were composed only of∼20 monomers of PrP(Sc. The tight correlation between conversion potency of small oligomers of human sPrP(Sc observed in vitro and duration of the disease suggests that sPrP(Sc conformers are an important determinant of prion strain characteristics that control the progression rate of the disease.

  16. Rate and predictors of conversion from unipolar to bipolar disorder: A systematic review and meta-analysis.

    Science.gov (United States)

    Kessing, Lars Vedel; Willer, Inge; Andersen, Per Kragh; Bukh, Jens Drachman

    2017-08-01

    For the first time to present a systematic review and meta-analysis of the conversion rate and predictors of conversion from unipolar disorder to bipolar disorder. A systematic literature search up to October 2016 was performed. For the meta-analysis, we only included studies that used survival analysis to estimate the conversion rate. A total of 31 studies were identified, among which 11 used survival analyses, including two register-based studies. The yearly rate of conversion to bipolar disorder decreased with time from 3.9% in the first year after study entry with a diagnosis of unipolar disorder to 3.1% in years 1-2, 1.0% in years 2-5 and 0.8% in years 5-10. A total of eight risk factors were evaluated comprising gender, age at onset of unipolar disorder, number of depressive episodes, treatment resistance to antidepressants, family history of bipolar disorder, the prevalence of psychotic depression, the prevalence of chronic depression, and severity of depression. It was not possible to identify risk factors that were consistently or mainly confirmed to predict conversion across studies. The conversion rate from unipolar to bipolar disorder decreases with time. It was not possible to identify predictors of conversion that were consistently or mainly confirmed across studies, which may be due to variations in methodology across studies. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  17. Understanding High Rate Behavior Through Low Rate Analog

    Science.gov (United States)

    2014-04-28

    challenges in high rate character- isation of polymers. The most important is that, owing to their low stress wavespeed, the structural response of...box’ tool, to provide supporting date for the rate dependent mechanical character- isation . Experiments were performed on a TA instruments Q800

  18. Line filter design of parallel interleaved VSCs for high power wind energy conversion systems

    DEFF Research Database (Denmark)

    Gohil, Ghanshyamsinh Vijaysinh; Bede, Lorand; Teodorescu, Remus

    2015-01-01

    The Voltage Source Converters (VSCs) are often connected in parallel in a Wind Energy Conversion System (WECS) to match the high power rating of the modern wind turbines. The effect of the interleaved carriers on the harmonic performance of the parallel connected VSCs is analyzed in this paper...... limit. In order to achieve the desired filter performance with optimal values of the filter parameters, the use of a LC trap branch with the conventional LCL filter is proposed. The expressions for the resonant frequencies of the proposed line filter are derived and used in the design to selectively...

  19. Gate controlled high efficiency ballistic energy conversion system

    NARCIS (Netherlands)

    Xie, Yanbo; Bos, Diederik; de Boer, Hans L.; van den Berg, Albert; Eijkel, Jan C.T.; Zengerle, R.

    2013-01-01

    Last year we demonstrated the microjet ballistic energy conversion system[1]. Here we show that the efficiency of such a system can be further improved by gate control. With gate control the electrical current generation is enhanced a hundred times with respect to the current generated from the zeta

  20. Proceedings of the technical committee on high conversion and high burnup reactors

    International Nuclear Information System (INIS)

    Shiroya, Seiji; Kanda, Keiji; Sekiya, Tamotsu

    1990-02-01

    The present issue is the proceedings of 'the Technical Committee on High Conversion and High Burnup Reactors' held at Kyoto University Research Reactor Institute (KURRI) on December 12 and 22, 1988. In this committee, members so much concerned with this theme were asked to report their recent accomplishment and activities. By such a program, the committee was intended to make a survey of future direction of research in this type of reactor. (J.P.N.)

  1. Influence of the rate of conversion of HT and HTO on projected radiation doses from release of molecular tritium

    International Nuclear Information System (INIS)

    Jacobs, D.G.; Easterly, C.E.; Phillips, J.E.

    1979-01-01

    Releases of tritium in the past have been largely in the form of tritiated water, and the projected radiation doses could be estimated by assuming tritium behaviour to parallel that of water. There is increasing interest in potential releases of tritium in the form of HT because of significant recent advances in fusion reactor research. Several recent studies have shown that bacteria containing the enzyme hydrogenase can catalyse the conversion of HT to HTO at rates several orders of magnitude faster than the rates measured in atmospheric systems. Rates of conversion in the soil have been combined with estimates of rates of permeation of HT into the soil and with global and local models depicting tritium transport and cycling. The results suggest that for the expected conversion rates, the impact on projected radiation doses should be relatively minor. (author)

  2. Monte Carlo calculation of dose rate conversion factors for external exposure to photon emitters in soil

    CERN Document Server

    Clouvas, A; Antonopoulos-Domis, M; Silva, J

    2000-01-01

    The dose rate conversion factors D/sub CF/ (absorbed dose rate in air per unit activity per unit of soil mass, nGy h/sup -1/ per Bq kg/sup -1/) are calculated 1 m above ground for photon emitters of natural radionuclides uniformly distributed in the soil. Three Monte Carlo codes are used: 1) The MCNP code of Los Alamos; 2) The GEANT code of CERN; and 3) a Monte Carlo code developed in the Nuclear Technology Laboratory of the Aristotle University of Thessaloniki. The accuracy of the Monte Carlo results is tested by the comparison of the unscattered flux obtained by the three Monte Carlo codes with an independent straightforward calculation. All codes and particularly the MCNP calculate accurately the absorbed dose rate in air due to the unscattered radiation. For the total radiation (unscattered plus scattered) the D/sub CF/ values calculated from the three codes are in very good agreement between them. The comparison between these results and the results deduced previously by other authors indicates a good ag...

  3. Highly efficient Cu-decorated iron oxide nanocatalyst for low pressure CO 2 conversion

    Energy Technology Data Exchange (ETDEWEB)

    Halder, Avik; Kilianová, Martina; Yang, Bing; Tyo, Eric C.; Seifert, Soenke; Prucek, Robert; Panáček, Aleš; Suchomel, Petr; Tomanec, Ondřej; Gosztola, David J.; Milde, David; Wang, Hsien-Hau; Kvítek, Libor; Zbořil, Radek; Vajda, Stefan

    2018-06-01

    We report a nanoparticulate iron oxide based catalyst for CO2 conversion with high efficiency at low pressures and on the effect of the presence of copper on the catalyst's restructuring and its catalytic performance. In situ X-ray scattering reveals the restructuring of the catalyst at the nanometer scale. In situ X-ray absorption near edge structure (XANES) shows the evolution of the composition and oxidation state of the iron and copper components under reaction conditions along with the promotional effect of copper on the chemical transformation of the iron component. X-ray diffraction (XRD), XANES and Raman spectroscopy proved that the starting nano catalyst is composed of iron oxides differing in chemical nature (alpha-Fe2O3, Fe3O4, FeO(OH)) and dimensionality, while the catalyst after CO2 conversion was identified as a mixture of alpha-Fe, Fe3C, and traces of Fe5C2. The significant increase of the rate CO2 is turned over in the presence of copper nanoparticles indicates that Cu nanoparticles activate hydrogen, which after spilling over to the neighbouring iron sites, facilitate a more efficient conversion of carbon dioxide.

  4. Linear constraint relations in biochemical reaction systems: I. Classification of the calculability and the balanceability of conversion rates.

    Science.gov (United States)

    van der Heijden, R T; Heijnen, J J; Hellinga, C; Romein, B; Luyben, K C

    1994-01-05

    Measurements provide the basis for process monitoring and control as well as for model development and validation. Systematic approaches to increase the accuracy and credibility of the empirical data set are therefore of great value. In (bio)chemical conversions, linear conservation relations such as the balance equations for charge, enthalpy, and/or chemical elements, can be employed to relate conversion rates. In a pactical situation, some of these rates will be measured (in effect, be calculated directly from primary measurements of, e.g., concentrations and flow rates), as others can or cannot be calculated from the measured ones. When certain measured rates can also be calculated from other measured rates, the set of equations, the accuracy and credibility of the measured rates can indeed be improved by, respectively, balancing and gross error diagnosis. The balanced conversion rates are more accurate, and form a consistent set of data, which is more suitable for further application (e.g., to calculate nonmeasured rates) than the raw measurements. Such an approach has drawn attention in previous studies. The current study deals mainly with the problem of mathematically classifying the conversion rates into balanceable and calculable rates, given the subset of measured rates. The significance of this problem is illustrated with some examples. It is shown that a simple matrix equation can be derived that contains the vector of measured conversion rates and the redundancy matrix R. Matrix R plays a predominant role in the classification problem. In supplementary articles, significance of the redundancy matrix R for an improved gross error diagnosis approach will be shown. In addition, efficient equations have been derived to calculate the balanceable and/or calculable rates. The method is completely based on matrix algebra (principally different from the graph-theoretical approach), and it is easily implemented into a computer program. (c) 1994 John Wiley & Sons

  5. Determining the rate of forest conversion in Mato Grosso, Brazil, using Landsat MSS and AVHRR data

    Science.gov (United States)

    Nelson, Ross; Horning, Ned; Stone, Thomas A.

    1987-01-01

    AVHRR-LAC thermal data and Landsat MSS and TM spectral data were used to estimate the rate of forest clearing in Mato Grosso, Brazil, between 1981 and 1984. The Brazilian state was stratified into forest and nonforest. A list sampling procedure was used in the forest stratum to select Landsat MSS scenes for processing based on estimates of fire activity in the scenes. Fire activity in 1984 was estimated using AVHRR-LAC thermal data. State-wide estimates of forest conversion indicate that between 1981 and 1984, 353,966 ha + or - 77,000 ha (0.4 percent of the state area) were converted per year. No evidence of reforestation was found in this digital sample. The relationship between forest clearing rate (based on MSS-TM analysis) and fire activity (estimated using AVHRR data) was noisy (R-squared = 0.41). The results suggest that AVHRR data may be put to better use as a stratification tool than as a subsidiary variable in list sampling.

  6. TEKNIK ESTIMASI GERAK PENCARIAN PENUH DENGAN AKURASI SETENGAH PIKSEL UNTUK FRAME RATE UP CONVERSION VIDEO

    Directory of Open Access Journals (Sweden)

    ary satya prabhawa

    2014-10-01

    Full Text Available ABSTRAK Saat ini Teknologi video digital banyak digunakan pada aplikasi hiburan, contohnya adalah TV Digital dengan format HD. Dengan frame rate tinggi, pengkodean video akan menghasil laju bit lebih tinggi yaitu sampai 15 – 30 fps. Permasalahannya adalah kapasitas saluran transmisi memiliki kapasitas terbatas. Solusinya adalah menurunkan laju bit dengan menurunkan jumlah frame video ke penerima. Skema ini dikenal dengan Frame Rate Up-Conversion (FRUC video, dimana frame yang di encoder akan direkonstruksi kembali di decoder dengan membangkitkan frame intermediate (FI. FI dibangkitkan dengan teknik Motion Compensation Interpolation (MCI. Terkait dengan metode FRUC, penelitian ini mengajukan skema MCI unidirectional dengan pencarian gerak akurasi setengah piksel. Pada skema ini, sebuah motion vector (MV kandidat akan dicari di frame referensi, proses estimasi gerak dilakukan dengan menambah piksel sisipan diantara piksel eksisting. Sasarannya adalah meningkatkan akurasi MV kandidat. Hasil simulasi menunjukkan bahwa metode yang diajukan lebih baik sampai sebesar masing – masing 3,21 dB dan 3,11 dB pada wilayah pencarian 7 dan 15 piksel dibandingkan dengan metode frame repetition untuk sekuen video foreman dan hall monitor.

  7. Theoretical determination of spectrum-exposure rate conversion operator of HPGe detector and its application to the measurement of environmental gamma-ray exposure rate

    International Nuclear Information System (INIS)

    Park, Ch.M.; Choi, B.I.; Kwak, S.S.; Ji, P.K.; Kim, T.W.; Park, Y.W.; Yoon, B.K.

    1993-01-01

    A conversion operator between spectrum and exposure rate, using a portable HPGe detector for environmental radiation monitoring, was determined theoretically under the assumption of uniform distribution of radiation source on the ground surface. The measurement results were compared with those of a pressurized ionization chamber. The results obtained with the HPGe detector were slightly lower. The method can be easily applied to any gamma ray detector to obtain a spectrum - exposure-rate conversion factor for computing the exposure rate of environmental gamma radiation. (N.T.) 15 refs.; 6 figs.; 3 tabs

  8. Internal conversion in highly stripped 83Kr ions

    International Nuclear Information System (INIS)

    Copnell, J.; Phillips, W.R.; Barnett, A.R.; Rehm, K.E.; Ahmad, I.; Gehring, J.; Glagola, B.G.; Kutschera, W.

    1995-01-01

    The total decay probabilities per unit time of the first excited 9.4-keV state in 83 Kr have been measured in ions of ionicity q from 28 to 32. Using a γ-decay probability per unit time of 0.255(2)x10 6 s -1 gives internal conversion coefficients of 14.6(11), 14.9(10), 14.1(9), 14.6(11), and 15.2(24) for q=28--32, respectively. These values are compared with theoretical predictions

  9. High-capacity lithium-ion battery conversion cathodes based on iron fluoride nanowires and insights into the conversion mechanism.

    Science.gov (United States)

    Li, Linsen; Meng, Fei; Jin, Song

    2012-11-14

    The increasing demands from large-scale energy applications call for the development of lithium-ion battery (LIB) electrode materials with high energy density. Earth abundant conversion cathode material iron trifluoride (FeF(3)) has a high theoretical capacity (712 mAh g(-1)) and the potential to double the energy density of the current cathode material based on lithium cobalt oxide. Such promise has not been fulfilled due to the nonoptimal material properties and poor kinetics of the electrochemical conversion reactions. Here, we report for the first time a high-capacity LIB cathode that is based on networks of FeF(3) nanowires (NWs) made via an inexpensive and scalable synthesis. The FeF(3) NW cathode yielded a discharge capacity as high as 543 mAh g(-1) at the first cycle and retained a capacity of 223 mAh g(-1) after 50 cycles at room temperature under the current of 50 mA g(-1). Moreover, high-resolution transmission electron microscopy revealed the existence of continuous networks of Fe in the lithiated FeF(3) NWs after discharging, which is likely an important factor for the observed improved electrochemical performance. The loss of active material (FeF(3)) caused by the increasingly ineffective reconversion process during charging was found to be a major factor responsible for the capacity loss upon cycling. With the advantages of low cost, large quantity, and ease of processing, these FeF(3) NWs are not only promising battery cathode materials but also provide a convenient platform for fundamental studies and further improving conversion cathodes in general.

  10. [High gene conversion frequency between genes encoding 2-deoxyglucose-6-phosphate phosphatase in 3 Saccharomyces species].

    Science.gov (United States)

    Piscopo, Sara-Pier; Drouin, Guy

    2014-05-01

    Gene conversions are nonreciprocal sequence exchanges between genes. They are relatively common in Saccharomyces cerevisiae, but few studies have investigated the evolutionary fate of gene conversions or their functional impacts. Here, we analyze the evolution and impact of gene conversions between the two genes encoding 2-deoxyglucose-6-phosphate phosphatase in S. cerevisiae, Saccharomyces paradoxus and Saccharomyces mikatae. Our results demonstrate that the last half of these genes are subject to gene conversions among these three species. The greater similarity and the greater percentage of GC nucleotides in the converted regions, as well as the absence of long regions of adjacent common converted sites, suggest that these gene conversions are frequent and occur independently in all three species. The high frequency of these conversions probably result from the fact that they have little impact on the protein sequences encoded by these genes.

  11. Management of marine cage aquaculture. Environmental carrying capacity method based on dry feed conversion rate.

    Science.gov (United States)

    Cai, Huiwen; Sun, Yinglan

    2007-11-01

    Marine cage aquaculture produces a large amount of waste that is released directly into the environment. To effectively manage the mariculture environment, it is important to determine the carrying capacity of an aquaculture area. In many Asian countries trash fish is dominantly used in marine cage aquaculture, which contains more water than pellet feed. The traditional nutrient loading analysis is for pellet feed not for trash fish feed. So, a more critical analysis is necessary in trash fish feed culturing areas. Corresponding to FCR (feed conversion rate), dry feed conversion rate (DFCR) was used to analyze the nutrient loadings from marine cage aquaculture where trash fish is used. Based on the hydrodynamic model and the mass transport model in Xiangshan Harbor, the relationship between the water quality and the waste discharged from cage aquaculture has been determined. The environmental carrying capacity of the aquaculture sea area was calculated by applying the models noted above. Nitrogen and phosphorus are the water quality parameters considered in this study. The simulated results show that the maximum nitrogen and phosphorus concentrations were 0.216 mg/L and 0.039 mg/L, respectively. In most of the sea area, the nutrient concentrations were higher than the water quality standard. The calculated environmental carrying capacity of nitrogen and phosphorus in Xiangshan Harbor were 1,107.37 t/yr and 134.35 t/yr, respectively. The waste generated from cage culturing in 2000 has already exceeded the environmental carrying capacity. Unconsumed feed has been identified as the most important origin of all pollutants in cage culturing systems. It suggests the importance of increasing the feed utilization and improving the feed composition on the basis of nutrient requirement. For the sustainable development of the aquaculture industry, it is an effective management measure to keep the stocking density and pollution loadings below the environmental carrying

  12. High-frequency thermal-electrical cycles for pyroelectric energy conversion

    International Nuclear Information System (INIS)

    Bhatia, Bikram; Damodaran, Anoop R.; Cho, Hanna; Martin, Lane W.; King, William P.

    2014-01-01

    We report thermal to electrical energy conversion from a 150 nm thick BaTiO 3 film using pyroelectric cycles at 1 kHz. A microfabricated platform enables temperature and electric field control with temporal resolution near 1 μs. The rapid electric field changes as high as 11 × 10 5  kV/cm-s, and temperature change rates as high as 6 × 10 5  K/s allow exploration of pyroelectric cycles in a previously unexplored operating regime. We investigated the effect of phase difference between electric field and temperature cycles, and electric field and temperature change rates on the electrical energy generated from thermal-electrical cycles based on the pyroelectric Ericsson cycle. Complete thermodynamic cycles are possible up to the highest cycle rates tested here, and the energy density varies significantly with phase shifts between temperature and electric field waveforms. This work could facilitate the design and operation of pyroelectric cycles at high cycle rates, and aid in the design of new pyroelectric systems

  13. Genetic variation for growth rate, feed conversion efficiency, and disease resistance exists within a farmed population of rainbow trout

    DEFF Research Database (Denmark)

    Henryon, Mark; Jokumsen, Alfred; Berg, Peer

    2002-01-01

    The objective of this study was to test that additive genetic (co)variation for survival, growth rate, feed conversion efficiency, and resistance to viral haemorrhagic septicaemia (VHS) exists within a farmed population of rainbow trout. Thirty sires and 30 dams were mated by a partly factorial...... the predicted breeding values for VHS resistance and the predicted breeding values for the body weights, body length, and feed conversion efficiencies. These results demonstrate that additive genetic (co)variation for growth rate, feed conversion efficiency, and VHS resistance does exist within the farmed...... mating design. Each sire was mated to two dams, and each dam was mated to two sires, producing 50 viable full-sib families (29 sires, 25 dams). The fish from these families were reared for a 215-day growout period, and were assessed for survival between days 52 and 215, growth rate (i.e., body weight...

  14. All-Optical Ultra-High-Speed OFDM to Nyquist-WDM Conversion Based on Complete Optical Fourier Transformation

    DEFF Research Database (Denmark)

    Guan, Pengyu; Røge, Kasper Meldgaard; Mulvad, Hans Christian Hansen

    2016-01-01

    We propose a novel all-optical ultra-high-speed orthogonal frequency-division multiplexing (OFDM) to Nyquist wavelength-division multiplexing (Nyquist-WDM) conversion scheme, achieved by exchanging the temporal and spectral profiles using a complete optical Fourier transformation (OFT). This scheme...... enables high-speed OFDM to Nyquist-WDM conversion without complex optical/electrical/optical conversion. The all-optical OFDM transmitter is based on the generation of OFDM symbols with a low duty cycle by rectangular temporal gating, which in combination with optical time-division multiplexing yields...... a higher symbol-rate OFDM signal. In the receiver, the converted Nyquist-WDM super-channel is WDM demultiplexed into individual Nyquist-WDM channels using a rectangular optical bandpass filter, followed by optical sampling at the intersymbol-interference free point. In the experimental demonstration...

  15. Numerical investigation of power requirements for ultra-high-speed serial-to-parallel conversion

    DEFF Research Database (Denmark)

    Lillieholm, Mads; Mulvad, Hans Christian Hansen; Palushani, Evarist

    2012-01-01

    We present a numerical bit-error rate investigation of 160-640 Gbit/s serial-to-parallel conversion by four-wave mixing based time-domain optical Fourier transformation, showing an inverse scaling of the required pump energy per bit with the bit rate.......We present a numerical bit-error rate investigation of 160-640 Gbit/s serial-to-parallel conversion by four-wave mixing based time-domain optical Fourier transformation, showing an inverse scaling of the required pump energy per bit with the bit rate....

  16. Conversion of zero point energy into high-energy photons

    Energy Technology Data Exchange (ETDEWEB)

    Ivlev, B. I. [Universidad Autonoma de San Luis Potosi, Instituto de Fisica, Av. Manuel Nava No. 6, Zona Universitaria, 78290 San Luis Potosi, SLP (Mexico)

    2016-11-01

    An unusual phenomenon, observed in experiments is studied. X-ray laser bursts of keV energy are emitted from a metal where long-living states, resulting in population inversion, are totally unexpected. Anomalous electron-photon states are revealed to be formed inside the metal. These states are associated with narrow, 10{sup -11} cm, potential well created by the local reduction of zero point electromagnetic energy. In contrast to analogous van der Waals potential well, leading to attraction of two hydrogen atoms, the depth of the anomalous well is on the order of 1 MeV. The states in that well are long-living which results in population inversion and subsequent laser generation observed. The X-ray emission, occurring in transitions to lower levels, is due to the conversion of zero point electromagnetic energy. (Author)

  17. Rates and Predictors of Conversion to Schizophrenia or Bipolar Disorder Following Substance-Induced Psychosis

    DEFF Research Database (Denmark)

    Starzer, Marie Stefanie Kejser; Nordentoft, Merete; Hjorthøj, Carsten

    2017-01-01

    . Self-harm after a substance-induced psychosis was significantly linked to a higher risk of converting to both schizophrenia and bipolar disorder. Half the cases of conversion to schizophrenia occurred within 3.1 years after a substance-induced psychosis, and half the cases of conversion to bipolar...

  18. Conceptual design of a FGM thermoelectric energy conversion system for high temperature heat source. 1. Design of thermoelectric energy conversion unit

    International Nuclear Information System (INIS)

    Kambe, Mitsuru; Teraki, Junichi; Hirano, Toru.

    1996-01-01

    Thermoelectric (TE) power conversion system has been focused as a candidate of direct energy conversion systems for high temperature heat source to meet the various power requirements in next century. A concept of energy conversion unit by using TE cell elements combined with FGM compliant pads has been presented to achieve high thermal energy density as well as high energy conversion efficiency. An energy conversion unit consists of 8 couples of P-N cell elements sandwiched between two FGM compliant pads. Performance analysis revealed that the power generated by this unit was 11 watts which is nearly ten times as much as conventional unit of the same size. Energy conversion efficiency of 12% was expected based on the assumption of ZT = 1. All the member of compliant pads as well as TE cells could be bonded together to avoid thermal resistance. (author)

  19. Modeling of large aperture third harmonic frequency conversion of high power Nd:glass laser systems

    International Nuclear Information System (INIS)

    Henesian, M.A.; Wegner, P.J.; Speck, D.R.; Bibeau, C.; Ehrlich, R.B.; Laumann, C.W.; Lawson, J.K.; Weiland, T.L.

    1991-01-01

    To provide high-energy, high-power beams at short wavelengths for inertial-confinement-fusion experiments, we routinely convert the 1.053-μm output of the Nova, Nd:phosphate-glass, laser system to its third-harmonic wavelength. We describe performance and conversion efficiency modeling of the 3 x 3 arrays potassium-dihydrogen-phosphate crystal plates used for type II/type II phase-matched harmonic conversion of Nova 0.74-m diameter beams, and an alternate type I/type II phase-matching configuration that improves the third-harmonic conversion efficiency. These arrays provide energy conversion of up to 65% and intensity conversion to 70%. 19 refs., 11 figs

  20. Influence on moisture and hydrocarbons on conversion rate of tritium in catalytic reactors of fusion-DEMO detritiation system

    International Nuclear Information System (INIS)

    Edao, Yuki; Sato, Katsumi; Iwai, Yasunori; Hayashi, Takumi

    2017-01-01

    Thoughtful consideration of abnormal events such as fire is required to design and qualify a detritiation system (DS) of a nuclear fusion facility. Since conversion of tritium to tritiated vapor over catalyst is the key process of the DS, it is indispensable to evaluate the effect of excess moisture and hydrocarbons produced by combustion of cables on tritium conversion rate considering fire events. We conducted demonstration tests on tritium conversion under the following representative conditions: (I) leakage of tritium, (II) leakage of tritium plus moisture, and (III) leakage of tritium plus hydrocarbons. Detritiation behavior in the simulated room was assessed, and the amount of catalyst to fulfill the requirement on tritium conversion rate was evaluated. The dominant parameters for detritiation are the concentration of hydrogen in air and catalyst temperature. The tritium in the simulated room was decreased for condition (I) following ventilation theory. An initial reduction in conversion rate was measured for condition (II). To recover the reduction smoothly, it is suggested to optimize the power of preheater. An increase in catalyst temperature by heat of reaction of hydrocarbon combustion was evaluated for condition (III). The heat balance of catalytic reactor is a point to be carefully investigated to avoid runaway of catalyst temperature. (author)

  1. High burn rate solid composite propellants

    Science.gov (United States)

    Manship, Timothy D.

    High burn rate propellants help maintain high levels of thrust without requiring complex, high surface area grain geometries. Utilizing high burn rate propellants allows for simplified grain geometries that not only make production of the grains easier, but the simplified grains tend to have better mechanical strength, which is important in missiles undergoing high-g accelerations. Additionally, high burn rate propellants allow for a higher volumetric loading which reduces the overall missile's size and weight. The purpose of this study is to present methods of achieving a high burn rate propellant and to develop a composite propellant formulation that burns at 1.5 inches per second at 1000 psia. In this study, several means of achieving a high burn rate propellant were presented. In addition, several candidate approaches were evaluated using the Kepner-Tregoe method with hydroxyl terminated polybutadiene (HTPB)-based propellants using burn rate modifiers and dicyclopentadiene (DCPD)-based propellants being selected for further evaluation. Propellants with varying levels of nano-aluminum, nano-iron oxide, FeBTA, and overall solids loading were produced using the HTPB binder and evaluated in order to determine the effect the various ingredients have on the burn rate and to find a formulation that provides the burn rate desired. Experiments were conducted to compare the burn rates of propellants using the binders HTPB and DCPD. The DCPD formulation matched that of the baseline HTPB mix. Finally, GAP-plasticized DCPD gumstock dogbones were attempted to be made for mechanical evaluation. Results from the study show that nano-additives have a substantial effect on propellant burn rate with nano-iron oxide having the largest influence. Of the formulations tested, the highest burn rate was a 84% solids loading mix using nano-aluminum nano-iron oxide, and ammonium perchlorate in a 3:1(20 micron: 200 micron) ratio which achieved a burn rate of 1.2 inches per second at 1000

  2. High pressure HC1 conversion of cellulose to glucose

    Energy Technology Data Exchange (ETDEWEB)

    Antonoplis, Robert Alexander [Univ. of California, Berkeley, CA (United States); Blanch, Harvey W. [Univ. of California, Berkeley, CA (United States); Wilke, Charles R. [Univ. of California, Berkeley, CA (United States)

    1981-08-01

    The production of ethanol from glucose by means of fermentation represents a potential long-range alternative to oil for use as a transportation fuel. Today's rising oil prices and the dwindling world supply of oil have made other fuels, such as ethanol, attractive alternatives. It has been shown that automobiles can operate, with minor alterations, on a 10% ethanol-gasoline mixture popularly known as gasohol. Wood has long been known as a potential source of glucose. Glucose may be obtained from wood following acid hydrolysis. In this research, it was found that saturating wood particles with HCl gas under pressure was an effective pretreatment before subjecting the wood to dilute acid hydrolysis. The pretreatment is necessary because of the tight lattice structure of cellulose, which inhibits dilute acid hydrolysis. HCl gas makes the cellulose more susceptible to hydrolysis and the glucose yield is doubled when dilute acid hydrolysis is preceded by HCl saturation at high pressure. The saturation was most effectively performed in a fluidized bed reactor, with pure HCl gas fluidizing equal volumes of ground wood and inert particles. The fluidized bed effectively dissipated the large amount of heat released upon HCl absorption into the wood. Batch reaction times of one hour at 314.7 p.s.i.a. gave glucose yields of 80% and xylose yields of 95% after dilute acid hydrolysis. A non-catalytic gas-solid reaction model, with gas diffusing through the solid limiting the reaction rate, was found to describe the HCl-wood reaction in the fluidized bed. HCl was found to form a stable adduct with the lignin residue in the wood, in a ratio of 3.33 moles per mole of lignin monomer. This resulted in a loss of 0.1453 lb. of HCl per pound of wood. The adduct was broken upon the addition of water. A process design and economic evaluation for a plant to produce 214 tons per day of glucose from air-dried ground Populus tristi gave an estimated glucose cost of 15.14 cents per pound

  3. High-rate lithium thionyl chloride cells

    Science.gov (United States)

    Goebel, F.

    1982-03-01

    A high-rate C cell with disc electrodes was developed to demonstrate current rates which are comparable to other primary systems. The tests performed established the limits of abuse beyond which the cell becomes hazardous. Tests include: impact, shock, and vibration tests; temperature cycling; and salt water immersion of fresh cells.

  4. Lithium thionyl chloride high rate discharge

    Science.gov (United States)

    Klinedinst, K. A.

    1980-04-01

    Improvements in high rate lithium thionyl chloride power technology achieved by varying the electrolyte composition, operating temperature, cathode design, and cathode composition are discussed. Discharge capacities are plotted as a function of current density, cell voltage, and temperature.

  5. Concomitant chemoradiotherapy with high dose rate brachytherapy ...

    African Journals Online (AJOL)

    Concomitant chemoradiotherapy with high dose rate brachytherapy as a definitive treatment modality for locally advanced cervical cancer. T Refaat, A Elsaid, N Lotfy, K Kiel, W Small Jr, P Nickers, E Lartigau ...

  6. LOGOS. HX: a core simulator for high conversion boiling water reactors

    International Nuclear Information System (INIS)

    Tsuiki, Makoto; Sakurada, Koichi; Yoshida, Hiroyuki.

    1988-01-01

    A three-dimensional physics simulator 'LOGOS. HX' has been developed for the designing analysis of high conversion boiling water reactor (HCBWR) cores. Its functions, calculational methods, and verification results will briefly be discussed. (author)

  7. Conversational Behaviors in Youth with High-Functioning ASD and Asperger Syndrome

    Science.gov (United States)

    Paul, Rhea; Orlovski, Stephanie Miles; Marcinko, Hillary Chuba; Volkmar, Fred

    2009-01-01

    Twenty-nine youth with autism spectrum disorders and 26 with typical development between 12 and 18 years of age were engaged in structured interviews (ADOS). The interviews were videotaped and rated for atypical conversational behaviors by trained raters, using the Pragmatic Rating Scale (Landa et al. "Psychol Med" 22:245-254, 1992). The ASD group…

  8. Is the bulk mode conversion important in high density helicon plasma?

    Energy Technology Data Exchange (ETDEWEB)

    Isayama, Shogo; Hada, Tohru [Interdisciplinary Graduate School of Engineering Sciences, Kyushu University, 6-1 Kasuga-Kohen, Kasuga, Fukuoka 816-8580 (Japan); Shinohara, Shunjiro [Institute of Engineering, Tokyo University of Agriculture and Technology, 2-24-16, Naka-cho, Koganei, Tokyo 184-8588 (Japan); Tanikawa, Takao [Research Institute of Science and Technology, Tokai University 4-1-1 Kitakaname, Hiratsuka, Kanagawa 259-1292 (Japan)

    2016-06-15

    In a high-density helicon plasma production process, a contribution of Trivelpiece-Gould (TG) wave for surface power deposition is widely accepted. The TG wave can be excited either due to an abrupt density gradient near the plasma edge (surface conversion) or due to linear mode conversion from the helicon wave in a density gradient in the bulk region (bulk mode conversion). By numerically solving the boundary value problem of linear coupling between the helicon and the TG waves in a background with density gradient, we show that the efficiency of the bulk mode conversion strongly depends on the dissipation included in the plasma, and the bulk mode conversion is important when the dissipation is small. Also, by performing FDTD simulation, we show the time evolution of energy flux associated with the helicon and the TG waves.

  9. Parametric study on thermal-hydraulic characteristics of high conversion light water reactor

    International Nuclear Information System (INIS)

    Mori, Takamasa; Nakagawa, Masayuki; Fujii, Sadao.

    1988-11-01

    To assess the feasibility of high conversion light water reactors (HCLWRs) from the thermal-hydraulic viewpoint, parametric study on thermal-hydraulic characteristics of HCLWR has been carried out by using a unit cell model. It is assumed that a HCLWR core is contained in a current 1000 MWe PWR plant. At the present study, reactor core parameters such as fuel pin diameter, pitch, core height and linear heat rate are widely and parametrically changed to survey the relation between these parameters and the basic thermal-hydraulic characteristics, i.e. maximum fuel temperature, minimum DNBR, reduction of reactor thermal output and so on. The validity of the unit cell model used has been ensured by comparison with the result of a subchannel analysis carried out for a whole core. (author)

  10. Analysis of Electric Vehicle DC High Current Conversion Technology

    Science.gov (United States)

    Yang, Jing; Bai, Jing-fen; Lin, Fan-tao; Lu, Da

    2017-05-01

    Based on the background of electric vehicles, it is elaborated the necessity about electric energy accurate metering of electric vehicle power batteries, and it is analyzed about the charging and discharging characteristics of power batteries. It is needed a DC large current converter to realize accurate calibration of power batteries electric energy metering. Several kinds of measuring methods are analyzed based on shunts and magnetic induction principle in detail. It is put forward power batteries charge and discharge calibration system principle, and it is simulated and analyzed ripple waves containing rate and harmonic waves containing rate of power batteries AC side and DC side. It is put forward suitable DC large current measurement methods of power batteries by comparing different measurement principles and it is looked forward the DC large current measurement techniques.

  11. High Strain Rate Characterisation of Composite Materials

    DEFF Research Database (Denmark)

    Eriksen, Rasmus Normann Wilken

    -reinforced polymers, were considered, and it was first shown that the loading history controls equilibrium process. Then the High-speed servo-hydraulic test machine was analysed in terms its ability to create a state of constant strain rate in the specimen. The invertible inertial forces in the load train prevented...... from designing and constructing a high-speed servo-hydraulic test machine and by performing a comprehensive test series. The difficulties encountered in the test work could be addressed with the developed analysis. The conclusion was that the High-speed servo-hydraulic test machine is less suited...... for testing fibre-reinforced polymers due to their elastic behaviour and low strain to failure. This is problematic as the High-speed servo-hydraulic test machine closes the gap between quasi-static tests rates and lower strain rates, which are achievable with the Split Hopkinson Pressure Bar. The Split...

  12. Conceptual process for conversion of high level waste to glass

    International Nuclear Information System (INIS)

    1975-01-01

    During a ten-year period highly radioactive wastes amounting to 22 million gallons of salt cake and 5 million gallons of wet sludge are to be converted to 1.2 million gallons of glass and 24 million gallons of decontaminated salt cake and placed in the new storage facilities which will provide high assurance of containment with minimal reliance on maintenance and surveillance. The glass will contain nearly all of the radioactivity in a form that is highly resistant to leaching and dispersion. The salt cake will contain a small amount of residual radioactivity. The process is shown in Figure 1 and the facilities may be arranged in seven modules to accomplish seven tasks, (1) remove wastes from tanks, (2) separate sludge and salt, (3) decontaminate salt, (4) solidify and package sludge and 137 Cs, (5) solidify and package decontaminated salt, (6) store high level waste, and (7) store decontaminated salt cake

  13. The relationship between high street footfall, attraction and conversion

    OpenAIRE

    Graham, CD

    2016-01-01

    The three critical measures of retail performance are often suggested to be “location, location, location”. However this generalisation, like many others in the literature, is of little practical use without underpinning empirical evidence. At a time when high streets find themselves under pressure from emerging omni-channel shopping behaviours, now more than ever retail managers need reliable performance benchmarks and comparators. We report findings from a mass observation of high street sh...

  14. Modified High Voltage Conversion Inverting Cuk DC-DC Converter for Renewable Energy Application

    DEFF Research Database (Denmark)

    Maroti, Pandav Kiran; Padmanaban, Sanjeevikumar; Wheeler, Patrick

    2017-01-01

    controlled device DC-DC topology. The voltage conversion ratio of proposed converter has increased by ten times of the conventional Cuk converterat a duty ratio of 90%. The detailed analysis of the voltage conversion ratio and losses occur due to internal resistance of components is done in the paper......The proposed exertion represents the modified high voltage conversion Cuk converter for renewable energy application. The proposed Cuk converter is a combination of the conventional boost converter and Cuk converter. The arrangement of the proposed converter make, such as, it becomes the single...

  15. SYNTACTIC ERRORS ANALYSIS IN THE CASUAL CONVERSATION 60 COMMITED BY TWO SENIOR HIGH STUDENTS

    Directory of Open Access Journals (Sweden)

    Anjar Setiawan

    2017-12-01

    Full Text Available Syntactic structures are the base of English grammar. This study was aimed to analyze the syntactic errors in the casual conversation commited by two senior high students of MAN 2 Semarang. The researcher used qualitative approach to analyze and interpret the meaning of casual conversation. Furthermore, the data collection had been transcribed and analyzed based on the areas of syntactic errors analysis. The findings of the study showed that all areas of syntactic errors happened during the conversation, included auxiliaries, tenses, article, preposition, and conjunction. Both speakers also had a relatively weak vocabulary and their sentences which were sometimes incomprehensible by the interlocutor.

  16. Thrombus Formation at High Shear Rates.

    Science.gov (United States)

    Casa, Lauren D C; Ku, David N

    2017-06-21

    The final common pathway in myocardial infarction and ischemic stroke is occlusion of blood flow from a thrombus forming under high shear rates in arteries. A high-shear thrombus forms rapidly and is distinct from the slow formation of coagulation that occurs in stagnant blood. Thrombosis at high shear rates depends primarily on the long protein von Willebrand factor (vWF) and platelets, with hemodynamics playing an important role in each stage of thrombus formation, including vWF binding, platelet adhesion, platelet activation, and rapid thrombus growth. The prediction of high-shear thrombosis is a major area of biofluid mechanics in which point-of-care testing and computational modeling are promising future directions for clinically relevant research. Further research in this area will enable identification of patients at high risk for arterial thrombosis, improve prevention and treatment based on shear-dependent biological mechanisms, and improve blood-contacting device design to reduce thrombosis risk.

  17. Evaluation of fluence to dose equivalent conversion factors for high energy radiations, (1)

    International Nuclear Information System (INIS)

    Sato, Osamu; Uehara, Takashi; Yoshizawa, Nobuaki; Iwai, Satoshi; Tanaka, Shun-ichi.

    1992-09-01

    Computer code system and basic data have been investigated for evaluating fluence to dose equivalent conversion factors for photons and neutrons up to 10 GeV. The present work suggested that the conversion factors would be obtained by incorporating effective quality factors of charged particles into the HERMES (High Energy Radiation Monte Carlo Elaborate System) code system. The effective quality factors for charged particles were calculated on the basis of the Q-L relationships specified in the ICRP Publication-60. (author)

  18. High efficiency thermal to electric energy conversion using selective emitters and spectrally tuned solar cells

    Science.gov (United States)

    Chubb, Donald L.; Flood, Dennis J.; Lowe, Roland A.

    1992-01-01

    Thermophotovoltaic (TPV) systems are attractive possibilities for direct thermal-to-electric energy conversion, but have typically required the use of black body radiators operating at high temperatures. Recent advances in both the understanding and performance of solid rare-earth oxide selective emitters make possible the use of TPV at temperatures as low as 1500 K. Depending on the nature of parasitic losses, overall thermal-to-electric conversion efficiencies greater than 20 percent are feasible.

  19. High-Power Microwave Transmission and Mode Conversion Program

    Energy Technology Data Exchange (ETDEWEB)

    Vernon, Ronald J. [Univ. of Wisconsin, Madison, WI (United States)

    2015-08-14

    This is a final technical report for a long term project to develop improved designs and design tools for the microwave hardware and components associated with the DOE Plasma Fusion Program. We have developed basic theory, software, fabrication techniques, and low-power measurement techniques for the design of microwave hardware associated gyrotrons, microwave mode converters and high-power microwave transmission lines. Specifically, in this report we discuss our work on designing quasi-optical mode converters for single and multiple frequencies, a new method for the analysis of perturbed-wall waveguide mode converters, perturbed-wall launcher design for TE0n mode gyrotrons, quasi-optical traveling-wave resonator design for high-power testing of microwave components, and possible improvements to the HSX microwave transmission line.

  20. High Conversion of Styrene, Ethylene, and Hydrogen to Linear Monoalkylbenzenes

    Directory of Open Access Journals (Sweden)

    David Hermann Lamparelli

    2018-05-01

    Full Text Available 1-Alkylbenzenes as a precursor of surfactants, can be produced from ethylene, styrene, and hydrogen. These intermediates, lacking tertiary carbons, are environmentally more benign than commercial ones that bear the aromatic ring linked to an internal carbon of the aliphatic chain. The one-pot synthesis of highly linear 1-alkylbenzenes (LABs through the homogeneous catalysis of olefin poly-insertion from cheap and largely available reagents can be carried out with a high turnover and selectivity. A purposely designed reactor that allows for the fine control of the three components feed, along with temperature, plays a key role in this achievement. A turnover of 194 g of LABs per mmol of catalyst per hour can be obtained with the simultaneous removal of polyethylene as a by-product.

  1. Metamaterial Receivers for High Efficiency Concentrated Solar Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Yellowhair, Julius E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Concentrating Solar Technologies Dept.; Kwon, Hoyeong [Univ. of Texas, Austin, TX (United States). Dept. of Electrical and Computer Engineering; Alu, Andrea [Univ. of Texas, Austin, TX (United States). Dept. of Electrical and Computer Engineering; Jarecki, Robert L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Concentrating Solar Technologies Dept.; Shinde, Subhash L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Concentrating Solar Technologies Dept.

    2016-09-01

    Operation of concentrated solar power receivers at higher temperatures (>700°C) would enable supercritical carbon dioxide (sCO2) power cycles for improved power cycle efficiencies (>50%) and cost-effective solar thermal power. Unfortunately, radiative losses at higher temperatures in conventional receivers can negatively impact the system efficiency gains. One approach to improve receiver thermal efficiency is to utilize selective coatings that enhance absorption across the visible solar spectrum while minimizing emission in the infrared to reduce radiative losses. Existing coatings, however, tend to degrade rapidly at elevated temperatures. In this report, we report on the initial designs and fabrication of spectrally selective metamaterial-based absorbers for high-temperature, high-thermal flux environments important for solarized sCO2 power cycles. Metamaterials are structured media whose optical properties are determined by sub-wavelength structural features instead of bulk material properties, providing unique solutions by decoupling the optical absorption spectrum from thermal stability requirements. The key enabling innovative concept proposed is the use of structured surfaces with spectral responses that can be tailored to optimize the absorption and retention of solar energy for a given temperature range. In this initial study through the Academic Alliance partnership with University of Texas at Austin, we use Tungsten for its stability in expected harsh environments, compatibility with microfabrication techniques, and required optical performance. Our goal is to tailor the optical properties for high (near unity) absorptivity across the majority of the solar spectrum and over a broad range of incidence angles, and at the same time achieve negligible absorptivity in the near infrared to optimize the energy absorbed and retained. To this goal, we apply the recently developed concept of plasmonic Brewster angle to suitably designed

  2. Organic nonlinear crystals and high power frequency conversion

    International Nuclear Information System (INIS)

    Velsko, S.P.; Davis, L.; Wang, F.; Monaco, S.; Eimerl, D.

    1987-12-01

    We are searching for a new second- and third-harmonic generators among the salts of chiral organic acids and bases. We discuss the relevant properties of crystals from this group of compounds, including their nonlinear and phasematching characteristics, linear absorption, damage threshold and crystal growth. In addition, we summarize what is known concerning other nonlinear optical properties of these crystals, such as two-photon absorption, nonlinear refractive index, and stimulated Raman thresholds. A preliminary assessment is made of the potential of these materials for use in future high power, large aperture lasers such as those used for inertial confinement fusion experiments. 14 refs., 1 fig., 3 tabs

  3. Organic nonlinear crystals and high power frequency conversion

    International Nuclear Information System (INIS)

    Velsko, S.P.; Davis, L.; Wang, F.; Monaco, S.; Eimerl, D.

    1987-01-01

    The authors are searching for new second and third harmonic generators among the salts of organic acids and bases. They discuss the relevant properties of crystals from this group of compounds, including their nonlinear and phasematching characteristics, linear absorption, damage threshold and crystal growth. In addition, they summarize what is known concerning other nonlinear optical properties of these crystals, such as two-photon absorption, nonlinear refractive index, and stimulated Raman thresholds. A preliminary assessment is made of the potential of these materials for use in future high power, large aperture lasers such as those used for inertial confinement fusion experiments

  4. A Switched-Capacitor Based High Conversion Ratio Converter for Renewable Energy Applications

    DEFF Research Database (Denmark)

    Li, Kerui; Yin, Zhijian; Yang, Yongheng

    2017-01-01

    A high step-up switched-capacitor based converter is proposed in this paper. The proposed converter features high conversion ratio, low voltage stress and continuous input current, which makes it very suitable for renewable energy applications like photovoltaic systems. More importantly...... voltage gain, low voltage stress on the switches, continuous input current, and relatively high efficiency....

  5. Mathematical modeling of high-rate Anammox UASB reactor based on granular packing patterns

    International Nuclear Information System (INIS)

    Tang, Chong-Jian; He, Rui; Zheng, Ping; Chai, Li-Yuan; Min, Xiao-Bo

    2013-01-01

    Highlights: ► A novel model was conducted to estimate volumetric nitrogen conversion rates. ► The packing patterns of the granules in Anammox reactor are investigated. ► The simple cubic packing pattern was simulated in high-rate Anammox UASB reactor. ► Operational strategies concerning sludge concentration were proposed by the modeling. -- Abstract: A novel mathematical model was developed to estimate the volumetric nitrogen conversion rates of a high-rate Anammox UASB reactor based on the packing patterns of granular sludge. A series of relationships among granular packing density, sludge concentration, hydraulic retention time and volumetric conversion rate were constructed to correlate Anammox reactor performance with granular packing patterns. It was suggested that the Anammox granules packed as the equivalent simple cubic pattern in high-rate UASB reactor with packing density of 50–55%, which not only accommodated a high concentration of sludge inside the reactor, but also provided large pore volume, thus prolonging the actual substrate conversion time. Results also indicated that it was necessary to improve Anammox reactor performance by enhancing substrate loading when sludge concentration was higher than 37.8 gVSS/L. The established model was carefully calibrated and verified, and it well simulated the performance of granule-based high-rate Anammox UASB reactor

  6. Mathematical modeling of high-rate Anammox UASB reactor based on granular packing patterns

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Chong-Jian, E-mail: chjtangzju@yahoo.com.cn [Department of Environmental Engineering, School of Metallurgical Science and Engineering, Central South University, Changsha 410083 (China); National Engineering Research Center for Control and Treatment of Heavy Metal Pollution, Changsha 410083 (China); He, Rui; Zheng, Ping [Department of Environmental Engineering, Zhejiang University, Zijingang Campus, Hangzhou 310058 (China); Chai, Li-Yuan; Min, Xiao-Bo [Department of Environmental Engineering, School of Metallurgical Science and Engineering, Central South University, Changsha 410083 (China); National Engineering Research Center for Control and Treatment of Heavy Metal Pollution, Changsha 410083 (China)

    2013-04-15

    Highlights: ► A novel model was conducted to estimate volumetric nitrogen conversion rates. ► The packing patterns of the granules in Anammox reactor are investigated. ► The simple cubic packing pattern was simulated in high-rate Anammox UASB reactor. ► Operational strategies concerning sludge concentration were proposed by the modeling. -- Abstract: A novel mathematical model was developed to estimate the volumetric nitrogen conversion rates of a high-rate Anammox UASB reactor based on the packing patterns of granular sludge. A series of relationships among granular packing density, sludge concentration, hydraulic retention time and volumetric conversion rate were constructed to correlate Anammox reactor performance with granular packing patterns. It was suggested that the Anammox granules packed as the equivalent simple cubic pattern in high-rate UASB reactor with packing density of 50–55%, which not only accommodated a high concentration of sludge inside the reactor, but also provided large pore volume, thus prolonging the actual substrate conversion time. Results also indicated that it was necessary to improve Anammox reactor performance by enhancing substrate loading when sludge concentration was higher than 37.8 gVSS/L. The established model was carefully calibrated and verified, and it well simulated the performance of granule-based high-rate Anammox UASB reactor.

  7. High frame rate synthetic aperture duplex imaging

    DEFF Research Database (Denmark)

    Stuart, Matthias Bo; Tomov, Borislav Gueorguiev; Pihl, Michael Johannes

    2013-01-01

    aperture flow imaging as demonstrated in this paper. Synthetic aperture, directional beamforming, and cross-correlation are used to produce B-mode and vector velocity images at high frame rates. The frame rate equals the effective pulse repetition frequency of each imaging mode. Emissions for making the B...... estimation is −1.8% and the relative standard deviation 5.4%. The approach can thus estimate both high and low velocities with equal accuracy and thereby makes it possible to present vector flow images with a high dynamic range. Measurements are made using the SARUS research scanner, a linear array......Conventional color flow images are limited in velocity range and can either show the high velocities in systole or be optimized for the lower diastolic velocities. The full dynamics of the flow is, thus, hard to visualize. The dynamic range can be significantly increased by employing synthetic...

  8. Skin dose rate conversion factors after contamination with radiopharmaceuticals: influence of contamination area, epidermal thickness and percutaneous absorption

    International Nuclear Information System (INIS)

    Covens, P; Berus, D; Caveliers, V; Struelens, L; Vanhavere, F; Verellen, D

    2013-01-01

    Skin contamination with radiopharmaceuticals can occur during biomedical research and daily nuclear medicine practice as a result of accidental spills, after contact with bodily fluids of patients or by inattentively touching contaminated materials. Skin dose assessment should be carried out by repeated quantification to map the course of the contamination together with the use of appropriate skin dose rate conversion factors. Contamination is generally characterised by local spots on the palmar surface of the hand and complete decontamination is difficult as a result of percutaneous absorption. This specific issue requires special consideration as to the skin dose rate conversion factors as a measure for the absorbed dose rate to the basal layer of the epidermis. In this work we used Monte Carlo simulations to study the influence of the contamination area, the epidermal thickness and the percutaneous absorption on the absorbed skin dose rate conversion factors for a set of 39 medical radionuclides. The results show that the absorbed dose to the basal layer of the epidermis can differ by up to two orders of magnitude from the operational quantity H p (0.07) when using an appropriate epidermal thickness in combination with the effect of percutaneous absorption. (paper)

  9. Baltimore District Tackles High Suspension Rates

    Science.gov (United States)

    Maxwell, Lesli A.

    2007-01-01

    This article reports on how the Baltimore District tackles its high suspension rates. Driven by an increasing belief that zero-tolerance disciplinary policies are ineffective, more educators are embracing strategies that do not exclude misbehaving students from school for offenses such as insubordination, disrespect, cutting class, tardiness, and…

  10. Endorectal high dose rate brachytherapy quality assurance

    International Nuclear Information System (INIS)

    Devic, S.; Vuong, T.; Evans, M.; Podgorsak, E.

    2008-01-01

    We describe our quality assurance method for preoperative high dose rate (HDR) brachytherapy of endorectal tumours. Reproduction of the treatment planning dose distribution on a daily basis is crucial for treatment success. Due to the cylindrical symmetry, two types of adjustments are necessary: applicator rotation and dose distribution shift along the applicator axis. (author)

  11. Advanced, High Power, Next Scale, Wave Energy Conversion Device

    Energy Technology Data Exchange (ETDEWEB)

    Mekhiche, Mike [Principal Investigator; Dufera, Hiz [Project Manager; Montagna, Deb [Business Point of Contact

    2012-10-29

    The project conducted under DOE contract DE‐EE0002649 is defined as the Advanced, High Power, Next Scale, Wave Energy Converter. The overall project is split into a seven‐stage, gated development program. The work conducted under the DOE contract is OPT Stage Gate III work and a portion of Stage Gate IV work of the seven stage product development process. The project effort includes Full Concept Design & Prototype Assembly Testing building on our existing PowerBuoy technology to deliver a device with much increased power delivery. Scaling‐up from 150kW to 500kW power generating capacity required changes in the PowerBuoy design that addressed cost reduction and mass manufacturing by implementing a Design for Manufacturing (DFM) approach. The design changes also focused on reducing PowerBuoy Installation, Operation and Maintenance (IO&M) costs which are essential to reducing the overall cost of energy. In this design, changes to the core PowerBuoy technology were implemented to increase capability and reduce both CAPEX and OPEX costs. OPT conceptually envisaged moving from a floating structure to a seabed structure. The design change from a floating structure to seabed structure would provide the implementation of stroke‐ unlimited Power Take‐Off (PTO) which has a potential to provide significant power delivery improvement and transform the wave energy industry if proven feasible.

  12. Dose conversion coefficients for high-energy photons, electrons, neutrons and protons

    International Nuclear Information System (INIS)

    Sakamoto, Yukio

    2005-01-01

    Dose conversion coefficients for photons, electrons and neutrons based on new ICRP recommendations were cited in the ICRP Publication 74, but the energy ranges of these data were limited and there are no data for high energy radiations produced in accelerator facilities. For the purpose of designing the high intensity proton accelerator facilities at JAERI, the dose evaluation code system of high energy radiations based on the HERMES code was developed and the dose conversion coefficients of effective dose were evaluated for photons, neutrons and protons up to 10 GeV, and electrons up to 100 GeV. The dose conversion coefficients of effective dose equivalent were also evaluated using quality factors to consider the consistency between radiation weighting factors and Q-L relationship. The effective dose conversion coefficients obtained in this work were in good agreement with those recently evaluated by using FLUKA code for photons and electrons with all energies, and neutrons and protons below 500 MeV. There were some discrepancy between two data owing to the difference of cross sections in the nuclear reaction models. The dose conversion coefficients of effective dose equivalents for high energy radiations based on Q-L relation in ICRP Publication 60 were evaluated only in this work. The previous comparison between effective dose and effective dose equivalent made it clear that the radiation weighting factors for high energy neutrons and protons were overestimated and the modification was required. (author)

  13. Patchy zooplankton grazing and high energy conversion efficiency: ecological implications of sandeel behavior and strategy

    DEFF Research Database (Denmark)

    Deurs, Mikael van; Christensen, Asbjørn; Rindorf, Anna

    2013-01-01

    of prey. Here we studied zooplankton consumption and energy conversion efficiency of lesser sandeel (Ammodytes marinus) in the central North Sea, using stomach data, length and weight-at-age data, bioenergetics, and hydrodynamic modeling. The results suggested: (i) Lesser sandeel in the Dogger area depend...... sandeel densities and growth rates per area than larger habitats...

  14. The "polyenviromic risk score": Aggregating environmental risk factors predicts conversion to psychosis in familial high-risk subjects.

    Science.gov (United States)

    Padmanabhan, Jaya L; Shah, Jai L; Tandon, Neeraj; Keshavan, Matcheri S

    2017-03-01

    Young relatives of individuals with schizophrenia (i.e. youth at familial high-risk, FHR) are at increased risk of developing psychotic disorders, and show higher rates of psychiatric symptoms, cognitive and neurobiological abnormalities than non-relatives. It is not known whether overall exposure to environmental risk factors increases risk of conversion to psychosis in FHR subjects. Subjects consisted of a pilot longitudinal sample of 83 young FHR subjects. As a proof of principle, we examined whether an aggregate score of exposure to environmental risk factors, which we term a 'polyenviromic risk score' (PERS), could predict conversion to psychosis. The PERS combines known environmental risk factors including cannabis use, urbanicity, season of birth, paternal age, obstetric and perinatal complications, and various types of childhood adversity, each weighted by its odds ratio for association with psychosis in the literature. A higher PERS was significantly associated with conversion to psychosis in young, familial high-risk subjects (OR=1.97, p=0.009). A model combining the PERS and clinical predictors had a sensitivity of 27% and specificity of 96%. An aggregate index of environmental risk may help predict conversion to psychosis in FHR subjects. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Highly Efficient Spin-to-Charge Current Conversion in Strained HgTe Surface States Protected by a HgCdTe Layer

    Science.gov (United States)

    Noel, P.; Thomas, C.; Fu, Y.; Vila, L.; Haas, B.; Jouneau, P.-H.; Gambarelli, S.; Meunier, T.; Ballet, P.; Attané, J. P.

    2018-04-01

    We report the observation of spin-to-charge current conversion in strained mercury telluride at room temperature, using spin pumping experiments. We show that a HgCdTe barrier can be used to protect the HgTe from direct contact with the ferromagnet, leading to very high conversion rates, with inverse Edelstein lengths up to 2.0 ±0.5 nm . The influence of the HgTe layer thickness on the conversion efficiency is found to differ strongly from what is expected in spin Hall effect systems. These measurements, associated with the temperature dependence of the resistivity, suggest that these high conversion rates are due to the spin momentum locking property of HgTe surface states.

  16. Rapid slowing of the atrial fibrillatory rate after administration of AZD7009 predicts conversion of atrial fibrillation

    DEFF Research Database (Denmark)

    Aunes, Maria; Egstrup, Kenneth; Frison, Lars

    2014-01-01

    to sinus rhythm (SR) and were matched to 35 non-converters. The mean AFR before conversion was 231 fibrillations per minute (fpm), having decreased by 41%; in non-converters, it was 296 fpm at the end of infusion, having decreased by 26%. The rate of decrease was greater in converters at 5 min, -88 vs. -66......BACKGROUND: Effects on the atrial fibrillatory rate (AFR) were studied during infusion with the combined potassium and sodium channel blocker AZD7009. METHODS AND RESULTS: Patients with persistent atrial fibrillation (AF) were randomized to AZD7009 or placebo. Thirty-five patients converted...... fpm (p=0.02), and at 10 min, -133 vs. -111 fpm (p=0.048). The AFR-SD and the exponential decay decreased. A small left atrial area was the only baseline predictor of conversion to SR. CONCLUSIONS: AZD7009 produced a significantly more rapid decrease of the AFR in converters than in non...

  17. Conversion rate of para-hydrogen to ortho-hydrogen by oxygen: implications for PHIP gas storage and utilization.

    Science.gov (United States)

    Wagner, Shawn

    2014-06-01

    To determine the storability of para-hydrogen before reestablishment of the room temperature thermal equilibrium mixture. Para-hydrogen was produced at near 100% purity and mixed with different oxygen quantities to determine the rate of conversion to the thermal equilibrium mixture of 75: 25% (ortho: para) by detecting the ortho-hydrogen (1)H nuclear magnetic resonance using a 9.4 T imager. The para-hydrogen to ortho-hydrogen velocity constant, k, near room temperature (292 K) was determined to be 8.27 ± 1.30 L/mol · min(-1). This value was calculated utilizing four different oxygen fractions. Para-hydrogen conversion to ortho-hydrogen by oxygen can be minimized for long term storage with judicious removal of oxygen contamination. Prior calculated velocity rates were confirmed demonstrating a dependence on only the oxygen concentration.

  18. Determination of correction and conversion factor of exposure rate generated Gamma spectrometer GR-320 to Victoreen data

    International Nuclear Information System (INIS)

    Supardjo-AS; Mappa, Djody-Rachim; Nasrun-Syamsul; Syamsul-Hadi

    2000-01-01

    Exposure rate data of Muria Peninsula were generated from Victoreen-491 measurement and calculation of radioelement content in soil which were measured by Exploranium GR-320, using IAEA formula. However those data are not be comparable so the exposure rate calculated from Gamma Spectrometer data necessarily to be corrected. The correction factor was determinate by measuring the exposure rate of at the NMDC's back yard selected location using Victoreen-491 and Gamma Spectrometer Exploranium GR-320 . Correction factor was created by comparing mean exposure rate data that calculated from 30 data measured by Gamma Spectrometer instrument and to those Victoreen's exposure rate. Conversion factor was gained from comparing of total count data of Gamma Spectrometer Exploranium GR-320 to Victoreen's exposure rate data. The correction factor of Exploranium GR-320's exposure rate is 0.34 μR/hours, and the conversion factor of total count is 0.0092 μR/hours per c/m. Deviation Victoreen 491 = 4.7 % and Gamma Spectrometer Exploranium GR-320 8.6 %

  19. Turkey's regulatory plans for high enriched to low enriched conversion of TR-2 reactor core

    International Nuclear Information System (INIS)

    Guelol Oezdere, Oya

    2003-01-01

    Turkey is a developing country and has three nuclear facilities two of which are research reactors and one pilot fuel production plant. One of the two research reactors is TR-2 which is located in Cekmece site in Istanbul. TR-2 Reactor's core is composed of both high enriched and low enriched fuel and from high enriched to low enriched core conversion project will take place in year 2005. This paper presents the plans for drafting regulations on the safety analysis report updates for high enriched to low enriched core conversion of TR-2 reactor, the present regulatory structure of Turkey and licensing activities of nuclear facilities. (author)

  20. Low power ion spectrometer for high counting rates

    International Nuclear Information System (INIS)

    Klein, J.W.; Dullenkopf, P.; Glasmachers, A.; Melbert, J.; Winkelnkemper, W.

    1980-01-01

    This report describes in detail the electronic concept for a time-of-flight (TOF) ion spectrometer for high counting rates and high dynamic range which can be used as a satellite instrument. The detection principle of the spectrometer is based on a time-of-flight and energy measurement for each incident ion. The ionmass is related to these two quantities by a simple equation. The described approach for the mass identification systems is using an analog fast-slow concept: The fast TOF-signal preselects the gainstep in the much slower energy channel. The conversion time of the mass identifier is approximately 10 -6 s and the dynamic range of the energy channel is better than 10 3 (20 keV to 25 MeV). The purpose of this study was to demonstrate the feasibility of a TOF-spectrometer capable to measure the ion composition in planetary magnetospheres. (orig.) [de

  1. High strain rate behaviour of polypropylene microfoams

    Directory of Open Access Journals (Sweden)

    Martínez A.B.

    2012-08-01

    Full Text Available Microcellular materials such as polypropylene foams are often used in protective applications and passive safety for packaging (electronic components, aeronautical structures, food, etc. or personal safety (helmets, knee-pads, etc.. In such applications the foams which are used are often designed to absorb the maximum energy and are generally subjected to severe loadings involving high strain rates. The manufacture process to obtain polymeric microcellular foams is based on the polymer saturation with a supercritical gas, at high temperature and pressure. This method presents several advantages over the conventional injection moulding techniques which make it industrially feasible. However, the effect of processing conditions such as blowing agent, concentration and microfoaming time and/or temperature on the microstructure of the resulting microcellular polymer (density, cell size and geometry is not yet set up. The compressive mechanical behaviour of several microcellular polypropylene foams has been investigated over a wide range of strain rates (0.001 to 3000 s−1 in order to show the effects of the processing parameters and strain rate on the mechanical properties. High strain rate tests were performed using a Split Hopkinson Pressure Bar apparatus (SHPB. Polypropylene and polyethylene-ethylene block copolymer foams of various densities were considered.

  2. High strain rate behaviour of polypropylene microfoams

    Science.gov (United States)

    Gómez-del Río, T.; Garrido, M. A.; Rodríguez, J.; Arencón, D.; Martínez, A. B.

    2012-08-01

    Microcellular materials such as polypropylene foams are often used in protective applications and passive safety for packaging (electronic components, aeronautical structures, food, etc.) or personal safety (helmets, knee-pads, etc.). In such applications the foams which are used are often designed to absorb the maximum energy and are generally subjected to severe loadings involving high strain rates. The manufacture process to obtain polymeric microcellular foams is based on the polymer saturation with a supercritical gas, at high temperature and pressure. This method presents several advantages over the conventional injection moulding techniques which make it industrially feasible. However, the effect of processing conditions such as blowing agent, concentration and microfoaming time and/or temperature on the microstructure of the resulting microcellular polymer (density, cell size and geometry) is not yet set up. The compressive mechanical behaviour of several microcellular polypropylene foams has been investigated over a wide range of strain rates (0.001 to 3000 s-1) in order to show the effects of the processing parameters and strain rate on the mechanical properties. High strain rate tests were performed using a Split Hopkinson Pressure Bar apparatus (SHPB). Polypropylene and polyethylene-ethylene block copolymer foams of various densities were considered.

  3. More than words: The influence of affective content and linguistic style matches in online reviews on conversion rates

    OpenAIRE

    Ludwig, S.; de Ruyter, K.; Friedman, M.; Brüggen, E.; Wetzels, M.; Pfann, G.

    2013-01-01

    Customers increasingly rely on other consumers' reviews to make purchase decisions online. New insights into the customer review phenomenon can be derived from studying the semantic content and style properties of verbatim customer reviews to examine their influence on online retail sites' conversion rates. The authors employ text mining to extract changes in affective content and linguistic style properties of customer book reviews on Amazon.com. A dynamic panel data model reveals that the i...

  4. High dose rate endobronchial brachytherapy - treatment technique

    International Nuclear Information System (INIS)

    Carvalho, Heloisa de Andrade; Aisen, Salim; Haddad, Cecilia Maria Kalil; Nadalin, Wladimir; Pedreira Junior, Wilson Leite; Chavantes, Maria Cristina

    1998-01-01

    High dose rate endobronchial brachytherapy is efficient in symptom relief due to obstructive endobronchial malignancies. However, it's role in survival improvement for patients with lung cancer is not yet established. The use of this treatment in increasing, specially in the developing countries. The purpose of this paper is to present the treatment technique used in the Radiotherapy Department of the Hospital da Clinicas, University of Sao Paulo, based on an experience of 60 cases treated with 180 procedures. Some practical suggestions and rules adopted in the Department are described. The severe complications rate is 6.7%, demonstrating an adequate patient selection associated with the technique utilized. (author)

  5. Electronics for very high rate tracking detectors

    International Nuclear Information System (INIS)

    Williams, H.H.; Dressnandt, N.; Ekenberg, T.; Gerds, E.J.; Newcomer, F.M.; Tedja, S.; Van Berg, R.; Van der Speigel, J.

    1995-01-01

    Results are presented on a system of electronics designed for very high rate tracking detectors at the SSC and LHC. The primary goal was a system for signal detection, time measurement, and readout for the straw tracker for SDC. An integrated circuit incorporating eight channels of amplifier-shaper-discriminator (including detector tail cancellation), and two different integrated circuits for time measurement are described. The performance of tracking measurements up to counting rates of 8 MHz per wire is reported, as well as preliminary results from a baseline restoration circuit. (orig.)

  6. High-flux/high-temperature solar thermal conversion: technology development and advanced applications

    Directory of Open Access Journals (Sweden)

    Romero Manuel

    2016-01-01

    Full Text Available Solar Thermal Power Plants have generated in the last 10 years a dynamic market for renewable energy industry and a pro-active networking within R&D community worldwide. By end 2015, there are about 5 GW installed in the world, most of them still concentrated in only two countries, Spain and the US, though a rapid process of globalization is taking place in the last few years and now ambitious market deployment is starting in countries like South Africa, Chile, Saudi Arabia, India, United Arab Emirates or Morocco. Prices for electricity produced by today's plants fill the range from 12 to 16 c€/kWh and they are capital intensive with investments above 4000 €/kW, depending on the number of hours of thermal storage. The urgent need to speed up the learning curve, by moving forward to LCOE below 10 c€/kWh and the promotion of sun-to-fuel applications, is driving the R&D programmes. Both, industry and R&D community are accelerating the transformation by approaching high-flux/high-temperature technologies and promoting the integration with high-efficiency conversion systems.

  7. Eye Donation Awareness and Conversion Rate in Hospital Cornea Retrieval Programme in a Tertiary Hospital of Central India.

    Science.gov (United States)

    Sharma, Bhavana; Shrivastava, Ulka; Kumar, Kavita; Baghel, Rajendra; Khan, Farhana; Kulkarni, Shridhar

    2017-08-01

    Corneal blindness accounts for 6-8 million blinds in the world. In India, it is estimated that there are approximately 6.8 million people who have vision less than 6/60 in at least one eye due to corneal diseases. This study was done to assess the awareness about eye donation amongst attendants of critically ill and deceased patients, their willingness to donate eyes, the efficacy of grief counselling by Eye Donation Counsellors (EDC), its impact on the conversion rate and the reasons for poor donation rate. This prospective hospital based study was done in 554 participants (guardians of critically ill and deceased subjects) to understand the awareness of eye donation. Factors related to willingness for eye donation that influenced conversion to actual donation were evaluated. Data was analysed with tests for statistical significance: Chi square test; pdonation, time taken for motivation remained less than 12 hours, which was statistically significant (Chi square=106. pdonation in comparison to those who were unaware in a ratio of 2:1. Grief counsellors (57.5%) had the most influence among the causes that were facilitators of donation. Utilizing the services of eye donation counsellors is a promising way to motivate the guardians of deceased. Increasing the awareness in society, rendering simple assistances to next of kin and speeding the medico legal formalities can go a long way in increasing the conversion rate and hence actual donation.

  8. On the sensitivity of HCPWR [high conversion pressurized water reactors] microcell calculations to geometrical treatment

    International Nuclear Information System (INIS)

    Sbaffoni, Maria; Abbate, Maximo; Patino, Nestor

    1990-01-01

    Nuclear reactor microcell calculations are, normally, carried out using simplified geometrical models which do not include the total number of homogeneous zones actually present. Regarding the particular case of High Conversion Pressurized Water Reactors (HCPWR), the revision of this approximation has been done to determine the sensitivity of its neutronic parameters to the use of these models. The study was performed comparing multiplication factors, reaction rates and neutron spectra, obtained using different geometrical treatments for a HCPWR typical microcell. From the results, it can be asserted that, if only two zones should be used in the calculation, the model which dilutes the clad into the moderator gives best results for the neutron fluxes, but the model that mix it with the fuel is better for k-infinite and reaction rate values. Considering the significance of these parameters on the physical behaviour of the reactor, the last one is recommended for cell calculations. Even if there is a slight difference between the cells considered, some results of this work were also compared with those of the NEACRP HCLWR benchmark with good agreement, so it can be concluded that the methodology here used for data processing and calculations is applicable to HCR's cell studies. (Author)

  9. Transesterification of waste cooking oil: Process optimization and conversion rate evaluation

    International Nuclear Information System (INIS)

    Abd Rabu, R.; Janajreh, I.; Honnery, D.

    2013-01-01

    Highlights: ► The highest purity of the produced biodiesel determined by gas chromatography was 95%. ► Produced biodiesel samples fell within the requirements of American standard for biodiesel. ► The reaction order is 1st order with a rate constant of 0.01 min -1 in the above point min -1 . - Abstract: Biodiesel is a mono-alkyl ester of vegetable oil, animal fat, and recycled cooking oil. It is gaining importance in the quest of finding sustainable fuel as it is compatible with petrodiesel and its synthesis process is becoming more commercially deployable. It is commonly prepared by the transesterification of triglycerides or the esterification of free fatty acid with methanol by stirring and accelerated by the presence of base or acidic catalyst. In this work biodiesel was produced by transesterification of waste cooking oil (WCO) following different process settings with the objective to achieve maximum yield and purity. Due to immiscibility and reaction reversibility, high purity WCO biodiesel of 95% was produced at 12:1 alcohol to oil molar ratio at 1% w/w NaOH catalyst and under continuous mixing of 2 h at 60 °C. Chemical kinetics was determined for the optimal process and found to follow 1st order reaction rate with a rate constant ranges from 0.0035 to 0.0106 min −1 . The activation energy was also evaluated by running the experiment at three different temperatures and found to be near 25,496 J/mol. The distillation curve and properties of the resulted fuel was also assessed and were compared plausibly to ASTM biodiesel standards. Furthermore, the emitted soot from a diffusion wick flame was measured via opacity meter and clearly show the advantage of the biodiesel with a nearly an order of magnitude lower.

  10. A Four-Phase High Voltage Conversion Ratio Bidirectional DC-DC Converter for Battery Applications

    Directory of Open Access Journals (Sweden)

    Li-Kun Xue

    2015-06-01

    Full Text Available This study presents a four-phase interleaved high voltage conversion ratio bidirectional DC-DC converter circuit based on coupled inductors and switched capacitors, which can eliminate the defects of conventional high voltage conversion ratio bidirectional DC-DC converters in terms of high-voltage/current stress, less efficiency and low-power limitation. Parallel channels are used to reduce current stress at the low-voltage side and series connected switched capacitors are used to enlarge voltage conversion ratio, reduce voltage stress and achieve auto current sharing. This paper proposes the operation principle, feature analysis and optimization design considerations. On this basis the objectives of high voltage conversion ratio, low voltage/current stress, high power density, high efficiency and high-power applications can be achieved. Some experimental results based on a 500 W prototype converter (24 V to 48 V at low-voltage side, 400 V at high-voltage side are given to verify the theoretical analysis and the effectiveness of the proposed converter.

  11. Dose conversion coefficients for high-energy photons, electrons, neutrons and protons

    CERN Document Server

    Sakamoto, Y; Sato, O; Tanaka, S I; Tsuda, S; Yamaguchi, Y; Yoshizawa, N

    2003-01-01

    In the International Commission on Radiological Protection (ICRP) 1990 Recommendations, radiation weighting factors were introduced in the place of quality factors, the tissue weighting factors were revised, and effective doses and equivalent doses of each tissues and organs were defined as the protection quantities. Dose conversion coefficients for photons, electrons and neutrons based on new ICRP recommendations were cited in the ICRP Publication 74, but the energy ranges of theses data were limited and there are no data for high energy radiations produced in accelerator facilities. For the purpose of designing the high intensity proton accelerator facilities at JAERI, the dose evaluation code system of high energy radiations based on the HERMES code was developed and the dose conversion coefficients of effective dose were evaluated for photons, neutrons and protons up to 10 GeV, and electrons up to 100 GeV. The dose conversion coefficients of effective dose equivalent were also evaluated using quality fact...

  12. AREA EFFICIENT FRACTIONAL SAMPLE RATE CONVERSION ARCHITECTURE FOR SOFTWARE DEFINED RADIOS

    Directory of Open Access Journals (Sweden)

    Latha Sahukar

    2014-09-01

    Full Text Available The modern software defined radios (SDRs use complex signal processing algorithms to realize efficient wireless communication schemes. Several such algorithms require a specific symbol to sample ratio to be maintained. In this context the fractional rate converter (FRC becomes a crucial block in the receiver part of SDR. The paper presents an area optimized dynamic FRC block, for low power SDR applications. The limitations of conventional cascaded interpolator and decimator architecture for FRC are also presented. Extending the SINC function interpolation based architecture; towards high area optimization and providing run time configuration with time register are presented. The area and speed analysis are carried with Xilinx FPGA synthesis tools. Only 15% area occupancy with maximum clock speed of 133 MHz are reported on Spartan-6 Lx45 Field Programmable Gate Array (FPGA.

  13. Conversion between mini-mental state examination, montreal cognitive assessment, and dementia rating scale-2 scores in Parkinson's disease.

    Science.gov (United States)

    van Steenoven, Inger; Aarsland, Dag; Hurtig, Howard; Chen-Plotkin, Alice; Duda, John E; Rick, Jacqueline; Chahine, Lama M; Dahodwala, Nabila; Trojanowski, John Q; Roalf, David R; Moberg, Paul J; Weintraub, Daniel

    2014-12-01

    Cognitive impairment is one of the earliest, most common, and most disabling non-motor symptoms in Parkinson's disease (PD). Thus, routine screening of global cognitive abilities is important for the optimal management of PD patients. Few global cognitive screening instruments have been developed for or validated in PD patients. The Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and Dementia Rating Scale-2 (DRS-2) have been used extensively for cognitive screening in both clinical and research settings. Determining how to convert the scores between instruments would facilitate the longitudinal assessment of cognition in clinical settings and the comparison and synthesis of cognitive data in multicenter and longitudinal cohort studies. The primary aim of this study was to apply a simple and reliable algorithm for the conversion of MoCA to MMSE scores in PD patients. A secondary aim was to apply this algorithm for the conversion of DRS-2 to both MMSE and MoCA scores. The cognitive performance of a convenience sample of 360 patients with idiopathic PD was assessed by at least two of these cognitive screening instruments. We then developed conversion scores between the MMSE, MoCA, and DRS-2 using equipercentile equating and log-linear smoothing. The conversion score tables reported here enable direct and easy comparison of three routinely used cognitive screening assessments in PD patients. © 2014 International Parkinson and Movement Disorder Society.

  14. Maximum Efficiency of Thermoelectric Heat Conversion in High-Temperature Power Devices

    Directory of Open Access Journals (Sweden)

    V. I. Khvesyuk

    2016-01-01

    Full Text Available Modern trends in development of aircraft engineering go with development of vehicles of the fifth generation. The features of aircrafts of the fifth generation are motivation to use new high-performance systems of onboard power supply. The operating temperature of the outer walls of engines is of 800–1000 K. This corresponds to radiation heat flux of 10 kW/m2 . The thermal energy including radiation of the engine wall may potentially be converted into electricity. The main objective of this paper is to analyze if it is possible to use a high efficiency thermoelectric conversion of heat into electricity. The paper considers issues such as working processes, choice of materials, and optimization of thermoelectric conversion. It presents the analysis results of operating conditions of thermoelectric generator (TEG used in advanced hightemperature power devices. A high-temperature heat source is a favorable factor for the thermoelectric conversion of heat. It is shown that for existing thermoelectric materials a theoretical conversion efficiency can reach the level of 15–20% at temperatures up to 1500 K and available values of Ioffe parameter being ZT = 2–3 (Z is figure of merit, T is temperature. To ensure temperature regime and high efficiency thermoelectric conversion simultaneously it is necessary to have a certain match between TEG power, temperature of hot and cold surfaces, and heat transfer coefficient of the cooling system. The paper discusses a concept of radiation absorber on the TEG hot surface. The analysis has demonstrated a number of potentialities for highly efficient conversion through using the TEG in high-temperature power devices. This work has been implemented under support of the Ministry of Education and Science of the Russian Federation; project No. 1145 (the programme “Organization of Research Engineering Activities”.

  15. Chronic Depressive Symptomatology in Mild Cognitive Impairment Is Associated with Frontal Atrophy Rate which Hastens Conversion to Alzheimer Dementia.

    Science.gov (United States)

    Sacuiu, Simona; Insel, Philip S; Mueller, Susanne; Tosun, Duygu; Mattsson, Niklas; Jack, Clifford R; DeCarli, Charles; Petersen, Ronald; Aisen, Paul S; Weiner, Michael W; Mackin, R Scott

    2016-02-01

    Investigate the association of chronic depressive symptomatology (chrDS) with cortical atrophy rates and conversion to Alzheimer dementia (AD) over 3 years in mild cognitive impairment (MCI). In a multicenter, clinic-based study, MCI elderly participants were selected from the Alzheimer's Disease Neuroimaging Initiative repository, based on availability of both serial structural magnetic resonance imaging and chrDS endorsed on three depression-related items from the Neuropsychiatric Inventory Questionnaire (chrDS N = 32 or no depressive symptoms N = 62) throughout follow-up. Clinical and laboratory investigations were performed every 6 months during the first 2 years and yearly thereafter (median follow-up: 3 years; interquartile range: 1.5-4.0 years). Cortical atrophy rates in 16 predefined frontotemporoparietal regions affected in major depression and AD and the rate of incident AD at follow-up. ChrDS in a single domain amnestic MCI sample were associated with accelerated cortical atrophy in the frontal lobe and anterior cingulate but not with atrophy rates in temporomedial or other AD-affected regions. During follow-up, 38 participants (42.7%) developed AD. Participants with chrDS had 60% shorter conversion time to AD than those without depressive symptoms. This association remained significant in survival models adjusted for temporomedial atrophy rates and showed the same trend in models adjusted for frontal cortical atrophy rate, which all increased the risk of AD. Our results suggest that chrDS associated with progressive atrophy of frontal regions may represent an additional risk factor for conversion to dementia in MCI as opposite to representing typical prodromal AD symptomatology. Published by Elsevier Inc.

  16. Electron dose-rate conversion factors for external exposure of the skin from uniformly deposited activity on the body surface

    International Nuclear Information System (INIS)

    Kocher, D.C.; Eckerman, K.F.

    1987-01-01

    Dose-rate conversion factors have been calculated for external exposure of the skin from electrons emitted by sources that are deposited uniformly on the body surface. The dose-rate factors are obtained from electron scaled point kernels developed by Berger. The dose-rate factors are calculated at depths of 4, 8, and 40 mg cm-2 below the body surface as recommended by Whitton, and at a depth of 7 mg cm-2 as recommended in ICRP Publication 26 (ICRP77). The dependence of the dose-rate factors at selected depths on the energy of the emitted electrons is displayed. The dose-rate factors for selected radionuclides of potential importance in radiological assessments are tabulated

  17. High strain rate studies in rock

    International Nuclear Information System (INIS)

    Grady, D.

    1977-01-01

    Dynamic compression studies using high velocity impact are usually considered to involve a catastrophic process of indeterminate loading rate by which a material is brough to a shock compressed state. Although this is frequently the case, methods are also available to control the rate of strain during the shock compression process. One of the most accurate of these methods makes use of the anomalous nonlinear elastic property of glass to transform an initial shock or step wave input into a ramp wave of known amplitude and duration. Fused silica is the most carefully calibrated material for this purpose and, when placed between the test specimen and the impact projectile, can provide loading strain rates in the range of 10 4 /s to 10 6 /s for final stress states of approximately 3.9 GPa or less.Ramp wave compression experiments have been conducted on dolomite at strain rates of 3 x 10 4 /s. Both initial yielding and subsequent deformation at this strain rate agrees well with previous shock wave studies (epsilon-dotapprox.10 6 /s) and differs substantially from quasi-static measurements (epsilon-dotapprox.10 -4 /s). The ramp wave studies have also uncovered a pressure-induced phase transition in dolomite initiating at 4.0 GPa

  18. All-optical ultra-high-speed OFDM to Nyquist-WDM conversion

    DEFF Research Database (Denmark)

    Guan, Pengyu; Røge, Kasper Meldgaard; Mulvad, Hans Christian Hansen

    2015-01-01

    We propose an all-optical ultra-high-speed OFDM to Nyquist-WDM conversion scheme based on complete OFT. An 8-subcarrier 640 Gbit/s DPSK OFDM super-channel is converted to eight 80-Gbit/s Nyquist-WDM channels with BER <10−9 performance for all channels.......We propose an all-optical ultra-high-speed OFDM to Nyquist-WDM conversion scheme based on complete OFT. An 8-subcarrier 640 Gbit/s DPSK OFDM super-channel is converted to eight 80-Gbit/s Nyquist-WDM channels with BER

  19. Reconfigurable high-speed optical fibre networks: Optical wavelength conversion and switching using VCSELs to eliminate channel collisions

    Science.gov (United States)

    Boiyo, Duncan Kiboi; Chabata, T. V.; Kipnoo, E. K. Rotich; Gamatham, R. R. G.; Leitch, A. W. R.; Gibbon, T. B.

    2017-01-01

    We experimentally provide an alternative solution to channel collisions through up-wavelength conversion and switching by using vertical cavity surface-emitting lasers (VCSELs). This has been achieved by utilizing purely optical wavelength conversion on VCSELs at the low attenuation, 1550 nm transmission window. The corresponding transmission and bit error-rate (BER) performance evaluation is also presented. In this paper, two 1550 nm VCSELs with 50-150 GHz channel spacing are modulated with a 10 Gb/s NRZ PRBS 27-1 data and their interferences investigated. A channel interference penalty range of 0.15-1.63 dB is incurred for 150-50 GHz channel spacing without transmission. To avoid channel collisions and to minimize high interference penalties, the transmitting VCSEL with data is injected into the side-mode of a slave VCSEL to obtain a new up converted wavelength. A 16 dB extinction ratio of the incoming wavelength is achieved when a 15 dBm transmitting beam is injected into the side-mode of a -4.5 dBm slave VCSEL. At 8.5 Gb/s, a 1.1 dB conversion and a 0.5 dB transmission penalties are realized when the converted wavelength is transmitted over a 24.7 km G.655 fibre. This work offers a low-cost, effective wavelength conversion and channel switching to reduce channel collision probability by reconfiguring channels at the node of networks.

  20. Comparison of Radiation Dose Rates with the Flux to Dose Conversion Factors Recommended in ICRP-74 and ICRP-116

    International Nuclear Information System (INIS)

    Jeong, Hae Sun; Kil, A Reum; Lee, Jo Eun; Jeong, Hyo Joon; Kim, Eun Han; Han, Moon Hee; Hwang, Won Tae

    2016-01-01

    The evaluation of radiation shielding has been performed for the design and maintenance of various facilities using radioactive sources such as nuclear fuel, accelerator, and radionuclide. The conversion of flux to dose mainly used in nuclear and radiation fields has been generally made with the dose coefficients presented in ICRP Publication 74 (ICRP- 74), which are produced based on ICRP Publication 60. On the other hand, ICRP Publication 116 (ICRP-116), which adopts the protection system of ICRP Publication 103, has recently been published and provides the dose conversion coefficients calculated with a variety of Monte Carlo codes. The coefficients have more than an update of those in ICRP-74, including new particle types and a greatly expanded energy range. In this study, a shielding evaluation of a specific container for neutron and gamma sources was performed with the MCNP6 code. The dose rates from neutron and gamma-ray sources were calculated using the MCNP6 codes, and these results were based on the flux to dose conversion factors recommended in ICRP-74 and ICRP-116. As a result, the dose rates evaluated with ICRP-74 were generally shown higher than those with ICRP-116. For neutrons, the difference is mainly occurred by the decrease of radiation weighting factors in a part of energy ranges in the ICRP-116 recommendations. For gamma-rays, the ICRP-74 recommendation applied with the kerma approximation leads to overestimated results than the other assessment

  1. High repetition rate intense ion beam source

    International Nuclear Information System (INIS)

    Hammer, D.A.; Glidden, S.C.; Noonan, B.

    1992-01-01

    This final report describes a ≤ 150kV, 40kA, 100ns high repetition rate pulsed power system and intense ion beam source which is now in operation at Cornell University. Operation of the Magnetically-controlled Anode Plasma (MAP) ion diode at > 100Hz (burst mode for up to 10 pulse bursts) provides an initial look at repetition rate limitations of both the ion diode and beam diagnostics. The pulsed power systems are capable of ≥ 1kHz operation (up to 10 pulse bursts), but ion diode operation was limited to ∼100Hz because of diagnostic limitations. By varying MAP diode operating parameters, ion beams can be extracted at a few 10s of keV or at up to 150keV, the corresponding accelerating gap impedance ranging from about 1Ω to about 10Ω. The ability to make hundreds of test pulses per day at an average repetition rate of about 2 pulses per minute permits statistical analysis of diode operation as a function of various parameters. Most diode components have now survived more than 10 4 pulses, and the design and construction of the various pulsed power components of the MAP diode which have enabled us to reach this point are discussed. A high speed data acquisition system and companion analysis software capable of acquiring pulse data at 1ms intervals (in bursts of up to 10 pulses) and processing it in ≤ min is described

  2. High strain rate deformation of layered nanocomposites.

    Science.gov (United States)

    Lee, Jae-Hwang; Veysset, David; Singer, Jonathan P; Retsch, Markus; Saini, Gagan; Pezeril, Thomas; Nelson, Keith A; Thomas, Edwin L

    2012-01-01

    Insight into the mechanical behaviour of nanomaterials under the extreme condition of very high deformation rates and to very large strains is needed to provide improved understanding for the development of new protective materials. Applications include protection against bullets for body armour, micrometeorites for satellites, and high-speed particle impact for jet engine turbine blades. Here we use a microscopic ballistic test to report the responses of periodic glassy-rubbery layered block-copolymer nanostructures to impact from hypervelocity micron-sized silica spheres. Entire deformation fields are experimentally visualized at an exceptionally high resolution (below 10 nm) and we discover how the microstructure dissipates the impact energy via layer kinking, layer compression, extreme chain conformational flattening, domain fragmentation and segmental mixing to form a liquid phase. Orientation-dependent experiments show that the dissipation can be enhanced by 30% by proper orientation of the layers.

  3. High strain rate deformation of layered nanocomposites

    Science.gov (United States)

    Lee, Jae-Hwang; Veysset, David; Singer, Jonathan P.; Retsch, Markus; Saini, Gagan; Pezeril, Thomas; Nelson, Keith A.; Thomas, Edwin L.

    2012-11-01

    Insight into the mechanical behaviour of nanomaterials under the extreme condition of very high deformation rates and to very large strains is needed to provide improved understanding for the development of new protective materials. Applications include protection against bullets for body armour, micrometeorites for satellites, and high-speed particle impact for jet engine turbine blades. Here we use a microscopic ballistic test to report the responses of periodic glassy-rubbery layered block-copolymer nanostructures to impact from hypervelocity micron-sized silica spheres. Entire deformation fields are experimentally visualized at an exceptionally high resolution (below 10 nm) and we discover how the microstructure dissipates the impact energy via layer kinking, layer compression, extreme chain conformational flattening, domain fragmentation and segmental mixing to form a liquid phase. Orientation-dependent experiments show that the dissipation can be enhanced by 30% by proper orientation of the layers.

  4. A soft-switching coupled inductor bidirectional DC-DC converter with high-conversion ratio

    Science.gov (United States)

    Chao, Kuei-Hsiang; Jheng, Yi-Cing

    2018-01-01

    A soft-switching bidirectional DC-DC converter is presented herein as a way to improve the conversion efficiency of a photovoltaic (PV) system. Adoption of coupled inductors enables the presented converter not only to provide a high-conversion ratio but also to suppress the transient surge voltage via the release of the energy stored in leakage flux of the coupled inductors, and the cost can kept down consequently. A combined use of a switching mechanism and an auxiliary resonant branch enables the converter to successfully perform zero-voltage switching operations on the main switches and improves the efficiency accordingly. It was testified by experiments that our proposed converter works relatively efficiently in full-load working range. Additionally, the framework of the converter intended for testifying has high-conversion ratio. The results of a test, where a generating system using PV module array coupled with batteries as energy storage device was used as the low-voltage input side, and DC link was used as high-voltage side, demonstrated our proposed converter framework with high-conversion ratio on both high-voltage and low-voltage sides.

  5. High-frame-rate digital radiographic videography

    Science.gov (United States)

    King, Nicholas S. P.; Cverna, Frank H.; Albright, Kevin L.; Jaramillo, Steven A.; Yates, George J.; McDonald, Thomas E.; Flynn, Michael J.; Tashman, Scott

    1994-10-01

    High speed x-ray imaging can be an important tool for observing internal processes in a wide range of applications. In this paper we describe preliminary implementation of a system having the eventual goal of observing the internal dynamics of bone and joint reactions during loading. Two Los Alamos National Laboratory (LANL) gated and image intensified camera systems were used to record images from an x-ray image convertor tube to demonstrate the potential of high frame-rate digital radiographic videography in the analysis of bone and joint dynamics of the human body. Preliminary experiments were done at LANL to test the systems. Initial high frame-rate imaging (from 500 to 1000 frames/s) of a swinging pendulum mounted to the face of an X-ray image convertor tube demonstrated high contrast response and baseline sensitivity. The systems were then evaluated at the Motion Analysis Laboratory of Henry Ford Health Systems Bone and Joint Center. Imaging of a 9 inch acrylic disk with embedded lead markers rotating at approximately 1000 RPM, demonstrated the system response to a high velocity/high contrast target. By gating the P-20 phosphor image from the X-ray image convertor with a second image intensifier (II) and using a 100 microsecond wide optical gate through the second II, enough prompt light decay from the x-ray image convertor phosphor had taken place to achieve reduction of most of the motion blurring. Measurement of the marker velocity was made by using video frames acquired at 500 frames/s. The data obtained from both experiments successfully demonstrated the feasibility of the technique. Several key areas for improvement are discussed along with salient test results and experiment details.

  6. Irradiation Tests Supporting LEU Conversion of Very High Power Research Reactors in the US

    Energy Technology Data Exchange (ETDEWEB)

    Woolstenhulme, N. E.; Cole, J. I.; Glagolenko, I.; Holdaway, K. K.; Housley, G. K.; Rabin, B. H.

    2016-10-01

    The US fuel development team is developing a high density uranium-molybdenum alloy monolithic fuel to enable conversion of five high-power research reactors. Previous irradiation tests have demonstrated promising behavior for this fuel design. A series of future irradiation tests will enable selection of final fuel fabrication process and provide data to qualify the fuel at moderately-high power conditions for use in three of these five reactors. The remaining two reactors, namely the Advanced Test Reactor and High Flux Isotope Reactor, require additional irradiation tests to develop and demonstrate the fuel’s performance with even higher power conditions, complex design features, and other unique conditions. This paper reviews the program’s current irradiation testing plans for these moderately-high irradiation conditions and presents conceptual testing strategies to illustrate how subsequent irradiation tests will build upon this initial data package to enable conversion of these two very-high power research reactors.

  7. High counting rate resistive-plate chamber

    International Nuclear Information System (INIS)

    Peskov, V.; Anderson, D.F.; Kwan, S.

    1993-05-01

    Parallel-plate avalanche chambers (PPAC) are widely used in physics experiments because they are fast ( 5 counts/mm 2 . A resistive-plate chamber (RPC) is similar to the PPAC in construction except that one or both of the electrodes are made from high resistivity (≥10 10 Ω·cm) materials. In practice RPCs are usually used in the spark mode. Resistive electrodes are charged by sparks, locally reducing the actual electric field in the gap. The size of the charged surface is about 10 mm 2 , leaving the rest of the detector unaffected. Therefore, the rate capability of such detectors in the spark mode is considerably higher than conventional spark counters. Among the different glasses tested the best results were obtained with electron type conductive glasses, which obey Ohm's law. Most of the work with such glasses was done with high pressure parallel-plate chambers (10 atm) for time-of-flight measurements. Resistive glasses have been expensive and produced only in small quantities. Now resistive glasses are commercially available, although they are still expensive in small scale production. From the positive experience of different groups working with the resistive glasses, it was decided to review the old idea to use this glass for the RPC. This work has investigated the possibility of using the RPC at 1 atm and in the avalanche mode. This has several advantages: simplicity of construction, high rate capability, low voltage operation, and the ability to work with non-flammable gases

  8. Restorative Justice Conferencing, Oral Language Competence, and Young Offenders: Are These High-Risk Conversations?

    Science.gov (United States)

    Snow, Pamela

    2013-01-01

    This article is concerned with the oral language demands (both talking and listening) associated with restorative justice conferencing--an inherently highly verbal and conversational process. Many vulnerable young people (e.g., those in the youth justice system) have significant, yet unidentified language impairments, and these could compromise…

  9. On high interest rates in Brazil

    Directory of Open Access Journals (Sweden)

    Francisco Lafaiete Lopes

    2014-03-01

    Full Text Available This article examines the question of why interest rates are so high in Brazil as compared to the international average. It looks at theoretical arguments based on excessive government deficits, structural lack of private savings, inflation bias, excessive investment demand and fear of floating. An informal look at the evidence does not strongly corroborate any of these arguments. Hence a wise central bank should consider "testing" the market to make sure it is not dealing with an extreme equilibrium configuration or a long standing disequilibrium.

  10. Flashing motor at high transition rate

    International Nuclear Information System (INIS)

    Ai Baoquan; Wang Liqiu; Liu Lianggang

    2007-01-01

    The movement of a Brownian particle in a fluctuating two-state periodic potential is investigated. At high transition rate, we use a perturbation method to obtain the analytical solution of the model. It is found that the net current is a peaked function of thermal noise, barrier height and the fluctuation ratio between the two states. The thermal noise may facilitate the directed motion at a finite intensity. The asymmetry parameter of the potential is sensitive to the direction of the net current

  11. Modular High Temperature Gas-Cooled Reactor heat source for coal conversion

    International Nuclear Information System (INIS)

    Schleicher, R.W. Jr.; Lewis, A.C.

    1992-09-01

    In the industrial nations, transportable fuels in the form of natural gas and petroleum derivatives constitute a primary energy source nearly equivalent to that consumed for generating electric power. Nations with large coal deposits have the option of coal conversion to meet their transportable fuel demands. But these processes themselves consume huge amounts of energy and produce undesirable combustion by-products. Therefore, this represents a major opportunity to apply nuclear energy for both the environmental and energy conservation reasons. Because the most desirable coal conversion processes take place at 800 degree C or higher, only the High Temperature Gas-Cooled Reactors (HTGRs) have the potential to be adapted to coal conversion processes. This report provides a discussion of this utilization of HTGR reactors

  12. A high repetition rate XUV seeding source for FLASH2

    International Nuclear Information System (INIS)

    Willner, Arik

    2012-05-01

    Improved performance of free-electron laser (FEL) light sources in terms of timing stability, pulse shape and spectral properties of the amplified FEL pulses is of interest in material science, the fields of ultrafast dynamics, biology, chemistry and even special branches in industry. A promising scheme for such an improvement is direct seeding with high harmonic generation (HHG) in a noble gas target. A free-electron laser seeded by an external extreme ultraviolet (XUV) source is planned for FLASH2 at DESY in Hamburg. The requirements for the XUV/soft X-ray source can be summarized as follows: A repetition rate of at least 100 kHz in a 10 Hz burst is needed at variable wavelengths from 10 to 40 nm and pulse energies of several nJ within a single laser harmonic. This application requires a laser amplifier system with exceptional parameters, mJ-level pulse energy, 10-15 fs pulse duration at 100 kHz (1 MHz) burst repetition rate. A new optical parametric chirped-pulse amplification (OPCPA) system is under development in order to meet these requirements, and very promising results have been achieved in the last three years. In parallel to this development, a new HHG concept is necessary to sustain high average power of the driving laser system and to generate harmonics with high conversion efficiencies. Currently, the highest conversion efficiency with HHG has been demonstrated using gas-filled capillary targets. For our application, only a free-jet target can be used for HHG, in order to overcome damage threshold limitations of HHG target optics at a high repetition rate. A novel dual-gas multijet gas target has been developed and first experiments show remarkable control of the degree of phase matching forming the basis for improved control of the harmonic photon flux and the XUV pulse characteristics. The basic idea behind the dual-gas concept is the insertion of matching zones in between multiple HHG sources. These matching sections are filled with hydrogen which

  13. A high repetition rate XUV seeding source for FLASH2

    Energy Technology Data Exchange (ETDEWEB)

    Willner, Arik

    2012-05-15

    Improved performance of free-electron laser (FEL) light sources in terms of timing stability, pulse shape and spectral properties of the amplified FEL pulses is of interest in material science, the fields of ultrafast dynamics, biology, chemistry and even special branches in industry. A promising scheme for such an improvement is direct seeding with high harmonic generation (HHG) in a noble gas target. A free-electron laser seeded by an external extreme ultraviolet (XUV) source is planned for FLASH2 at DESY in Hamburg. The requirements for the XUV/soft X-ray source can be summarized as follows: A repetition rate of at least 100 kHz in a 10 Hz burst is needed at variable wavelengths from 10 to 40 nm and pulse energies of several nJ within a single laser harmonic. This application requires a laser amplifier system with exceptional parameters, mJ-level pulse energy, 10-15 fs pulse duration at 100 kHz (1 MHz) burst repetition rate. A new optical parametric chirped-pulse amplification (OPCPA) system is under development in order to meet these requirements, and very promising results have been achieved in the last three years. In parallel to this development, a new HHG concept is necessary to sustain high average power of the driving laser system and to generate harmonics with high conversion efficiencies. Currently, the highest conversion efficiency with HHG has been demonstrated using gas-filled capillary targets. For our application, only a free-jet target can be used for HHG, in order to overcome damage threshold limitations of HHG target optics at a high repetition rate. A novel dual-gas multijet gas target has been developed and first experiments show remarkable control of the degree of phase matching forming the basis for improved control of the harmonic photon flux and the XUV pulse characteristics. The basic idea behind the dual-gas concept is the insertion of matching zones in between multiple HHG sources. These matching sections are filled with hydrogen which

  14. High dose rate brachytherapy for oral cancer

    International Nuclear Information System (INIS)

    Yamazaki, Hideya; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Koizumi, Masahiko; Ogawa, Kazuhiko; Furukawa, Souhei

    2013-01-01

    Brachytherapy results in better dose distribution compared with other treatments because of steep dose reduction in the surrounding normal tissues. Excellent local control rates and acceptable side effects have been demonstrated with brachytherapy as a sole treatment modality, a postoperative method, and a method of reirradiation. Low-dose-rate (LDR) brachytherapy has been employed worldwide for its superior outcome. With the advent of technology, high-dose-rate (HDR) brachytherapy has enabled health care providers to avoid radiation exposure. This therapy has been used for treating many types of cancer such as gynecological cancer, breast cancer, and prostate cancer. However, LDR and pulsed-dose-rate interstitial brachytherapies have been mainstays for head and neck cancer. HDR brachytherapy has not become widely used in the radiotherapy community for treating head and neck cancer because of lack of experience and biological concerns. On the other hand, because HDR brachytherapy is less time-consuming, treatment can occasionally be administered on an outpatient basis. For the convenience and safety of patients and medical staff, HDR brachytherapy should be explored. To enhance the role of this therapy in treatment of head and neck lesions, we have reviewed its outcomes with oral cancer, including Phase I/II to Phase III studies, evaluating this technique in terms of safety and efficacy. In particular, our studies have shown that superficial tumors can be treated using a non-invasive mold technique on an outpatient basis without adverse reactions. The next generation of image-guided brachytherapy using HDR has been discussed. In conclusion, although concrete evidence is yet to be produced with a sophisticated study in a reproducible manner, HDR brachytherapy remains an important option for treatment of oral cancer. (author)

  15. High dose rate brachytherapy for oral cancer.

    Science.gov (United States)

    Yamazaki, Hideya; Yoshida, Ken; Yoshioka, Yasuo; Shimizutani, Kimishige; Furukawa, Souhei; Koizumi, Masahiko; Ogawa, Kazuhiko

    2013-01-01

    Brachytherapy results in better dose distribution compared with other treatments because of steep dose reduction in the surrounding normal tissues. Excellent local control rates and acceptable side effects have been demonstrated with brachytherapy as a sole treatment modality, a postoperative method, and a method of reirradiation. Low-dose-rate (LDR) brachytherapy has been employed worldwide for its superior outcome. With the advent of technology, high-dose-rate (HDR) brachytherapy has enabled health care providers to avoid radiation exposure. This therapy has been used for treating many types of cancer such as gynecological cancer, breast cancer, and prostate cancer. However, LDR and pulsed-dose-rate interstitial brachytherapies have been mainstays for head and neck cancer. HDR brachytherapy has not become widely used in the radiotherapy community for treating head and neck cancer because of lack of experience and biological concerns. On the other hand, because HDR brachytherapy is less time-consuming, treatment can occasionally be administered on an outpatient basis. For the convenience and safety of patients and medical staff, HDR brachytherapy should be explored. To enhance the role of this therapy in treatment of head and neck lesions, we have reviewed its outcomes with oral cancer, including Phase I/II to Phase III studies, evaluating this technique in terms of safety and efficacy. In particular, our studies have shown that superficial tumors can be treated using a non-invasive mold technique on an outpatient basis without adverse reactions. The next generation of image-guided brachytherapy using HDR has been discussed. In conclusion, although concrete evidence is yet to be produced with a sophisticated study in a reproducible manner, HDR brachytherapy remains an important option for treatment of oral cancer.

  16. Family Ratings of Communication Largely Reflect Expressive Language and Conversation-Level Ability in People With Aphasia.

    Science.gov (United States)

    Fucetola, Robert; Tabor Connor, Lisa

    2015-11-01

    Family ratings of communication and social interactions represent an important source of information about people with aphasia. Because of the reliance on family/partner ratings as an outcome measure in many aphasia treatment studies and in the clinic, there is a great need for the validation of commonly used family/partner rating measures, and a better understanding of predictors of family ratings of communication. The communication ability of 130 individuals with aphasia due to neurologic illness was rated by family members/partners on the Communicative Effectiveness Index (CETI; Lomas et al., 1989). Information on aphasia severity, mood, quality of life, nonverbal cognitive functioning, and various demographic factors was collected. Principal component analysis confirmed a 2-factor model best represents the relationships among CETI rating items, and this model largely consists of a conversation-level ability factor. Family ratings were largely predicted by the patient's expressive (not receptive) language but also patient self-perceived quality of communication life. Family/partners typically rate the effectiveness of communication based largely on expressive language, despite the fact that other aspects of the aphasia (e.g., listening comprehension) are as important for everyday communication.

  17. Effects of radiation transport on mass ablation rate and conversion efficiency in numerical simulations of inertial confinement fusion

    International Nuclear Information System (INIS)

    Gupta, N.K.

    2002-01-01

    The effects of radiation transport on hydrodynamic parameters of laser produced plasmas are studied. LTE and non-LTE atomic models are used to calculate multi group opacities and emissivities. Screened hydrogenic atom model is used to calculate the energy levels. The population densities of neutral to fully ionized ions are obtained by solving the steady state rate equations. Radiation transport is treated in multi-group diffusion or Sn method. A comparison is made between 1 and 100 group radiation transport and LTE and non-LTE models. For aluminium, multi group radiation transport leads to much higher mass ablation as compared to the 1 group and no radiation transport cases. This in turn leads to higher ablation pressures. However, for gold gray approximation gives higher mass ablation as compared to multi group simulations. LTE conversion efficiency of laser light into x-rays is more than the non-LTE estimates. For LTE as well as non-LTE cases, the one group approximation over-predicts the conversion efficiency Multi group non-LTE simulations predict that the conversion efficiency increases with laser intensity up to a maximum and then it decreases. (author)

  18. The modified gait abnormality rating scale in patients with a conversion disorder: a reliability and responsiveness study.

    Science.gov (United States)

    Vandenberg, Justin M; George, Deanna R; O'Leary, Andrea J; Olson, Lindsay C; Strassburg, Kaitlyn R; Hollman, John H

    2015-01-01

    Individuals with conversion disorder have neurologic symptoms that are not identified by an underlying organic cause. Often the symptoms manifest as gait disturbances. The modified gait abnormality rating scale (GARS-M) may be useful for quantifying gait abnormalities in these individuals. The purpose of this study was to examine the reliability, responsiveness and concurrent validity of GARS-M scores in individuals with conversion disorder. Data from 27 individuals who completed a rehabilitation program were included in this study. Pre- and post-intervention videos were obtained and walking speed was measured. Five examiners independently evaluated gait performance according to the GARS-M criteria. Inter- and intrarater reliability of GARS-M scores were estimated with intraclass correlation coefficients (ICCs). Responsiveness was estimated with the minimum detectable change (MDC). Pre- to post-treatment changes in GARS-M scores were analyzed with a dependent t-test. The correlation between GARS-M scores and walking speed was analyzed to assess concurrent validity. GARS-M scores were quantified with good-to-excellent inter- (ICC = 0.878) and intrarater reliability (ICC = 0.989). The MDC was 2 points. Mean GARS-M scores decreased from 7 ± 5 at baseline to 1 ± 2 at discharge (t26 = 7.411, p conversion disorder. GARS-M scores provide objective measures upon which treatment effects can be assessed. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. High-ratio voltage conversion in CMOS for efficient mains-connected standby

    CERN Document Server

    Meyvaert, Hans

    2016-01-01

    This book describes synergetic innovation opportunities offered by combining the field of power conversion with the field of integrated circuit (IC) design. The authors demonstrate how integrating circuits enables increased operation frequency, which can be exploited in power converters to reduce drastically the size of the discrete passive components. The authors introduce multiple power converter circuits, which are very compact as result of their high level of integration. First, the limits of high-power-density low-voltage monolithic switched-capacitor DC-DC conversion are investigated to enable on-chip power granularization. AC-DC conversion from the mains to a low voltage DC is discussed, enabling an efficient and compact, lower-power auxiliary power supply to take over the power delivery during the standby mode of mains-connected appliances, allowing the main power converter of these devices to be shut down fully. Discusses high-power-density monolithic switched-capacitor DC-DC conversion in bulk CMOS,...

  20. Ultra Fast, High Rep Rate, High Voltage Spark Gap Pulser

    Science.gov (United States)

    1995-07-01

    current rise time. The spark gap was designed to have a coaxial geometry reducing its inductance. Provisions were made to pass flowing gas between the...ULTRA FAST, HIGH REP RATE, HIGH VOLTAGE SPARK GAP PULSER Robert A. Pastore Jr., Lawrence E. Kingsley, Kevin Fonda, Erik Lenzing Electrophysics and...Modeling Branch AMSRL-PS-EA Tel.: (908)-532-0271 FAX: (908)-542-3348 U.S. Army Research Laboratory Physical Sciences Directorate Ft. Monmouth

  1. Conversion of Airborne Gamma ray Spectra to Ground Level Air Kerma Rates

    DEFF Research Database (Denmark)

    Bargholz, Kim; Korsbech, Uffe C C

    1997-01-01

    A new method for relating airborne gamma-ray spectra to dose rates and kerma rates at ground level is presented. Dependent on flying altitude 50 m to 125 m the method gives correct results for gamma energies above 250 keV respective 350 keV. At lower energies the method underestimate the dose...... or kerma rates; by having a large fraction of the ground level gamma-rays at energies below 350 keV special care should be taken at an interpretation of the results....

  2. Rates of intraoperative complications and conversion to laparotomy during laparoscopic ovariectomy performed by veterinary students: 161 cases (2010-2014).

    Science.gov (United States)

    Nylund, Adam M; Drury, Adam; Weir, Heather; Monnet, Eric

    2017-07-01

    OBJECTIVE To assess rates of intraoperative complications and conversion to laparotomy associated with supervised veterinary students performing laparoscopic ovariectomy in dogs. DESIGN Retrospective case series. ANIMALS 161 female shelter dogs for which elective laparoscopic ovariectomy had been performed by supervised senior (fourth-year) veterinary students from 2010 through 2014. PROCEDURES Medical records of all dogs were reviewed and data collected regarding duration of surgery, surgical complications and other characteristics, and whether conversion to laparotomy was required. RESULTS Laparoscopic ovariectomy was performed with a 2-cannula technique and a 10-mm vessel-sealing device for hemostasis in all dogs. A Veress needle was used for initial insufflation in 144 (89.4%) dogs; method of insufflation was not reported for the remaining 17 (10.6%) dogs. Mean ± SD duration of surgery was 114.90 ± 33.40 minutes. Surgical complications, all classified as minor blood loss, occurred in 24 (14.9%) dogs. These included splenic puncture during insertion of the Veress needle (n = 20 [12.4%]) and minor bleeding from the ovarian pedicle (4 [2.5%]). Splenic puncture required no intervention, and ovarian pedicle bleeding required application of the vessel-sealing device an additional time to control the bleeding. Two ovaries were dropped in the abdominal cavity at the time of removal. Both were retrieved without complication. Conversion to laparotomy was not required for any dog. All dogs were discharged from the hospital within 24 hours after surgery. CONCLUSIONS AND CLINICAL RELEVANCE Laparoscopic ovariectomy in dogs was performed safely by closely supervised novice surgeons, with only minor intraoperative complications encountered and no need for conversion to laparotomy.

  3. Precision measurements of high-energy conversion electron lines and determination of neutron binding energies

    International Nuclear Information System (INIS)

    Braumandl, F.

    1979-01-01

    The paper first discusses the energy accuracy of the BILL conversion electron spectrometer at the Grenoble high flux reactor. With an improved temperature stabilisation of the magnets, an energy accuracy of ΔE/E -5 can be reached. After this, highly exact measurements of high-energy conversion electron lines of the 200 Hg, 114 Cd, 165 Dy, 168 Er, 239 U nuclei and the 13 C, 28 Al 3 H and 92 Zr photoelectron lines were carried out. Energy calibration of the spectrometer was carried out in the 1.5 MeV to 6.5 MeV range with intensive high-energy transitions of the 200 Hg nucleus. Systematic calibration errors could be investigated by means of combinations between the calibration lines. A calibration for absolute energies was obtained by comparing low-energy gamma transitions of 200 Hg with the 411.8 keV gold standard. (orig.) [de

  4. Efficient video coding integrating MPEG-2 and picture-rate conversion

    NARCIS (Netherlands)

    Bruin, de F.J.; Bruls, W.H.A.; Burazerovic, D.; Haan, de G.

    2002-01-01

    We present an MPEG-2 compliant video codec using picture-rate upconversion during decoding. The upconversion autonomously regenerates major parts of frames without vectorial and residual data. Consequently, the bitrate is greatly reduced.

  5. Critical heat flux experiments for high conversion light water reactor, (3)

    International Nuclear Information System (INIS)

    Iwamura, Takamichi; Okubo, Tsutomu; Suemura, Takayuki; Hiraga, Fujio; Murao, Yoshio

    1990-03-01

    As a part of the thermal-hydraulic feasibility study of a high conversion light water reactor (HCLWR), critical heat flux (CHF) experiments were performed using triangular array rod bundles under steady-state and flow reduction transient conditions. The geometries of test sections were: rod outer diameter 9.5 mm, number of rods 4∼7, heated length 0.5∼1.0 m, and pitch to diameter ratio (P/D) 1.126∼1.2. The simulated fuel rod was a stainless steel tube and uniformly heated electrically with direct current. In the steady-state tests, pressures ranged: 1.0∼3.9 Mpa, mass velocities: 460∼4270 kg/s·m 2 , and exit qualities: 0.02∼0.35. In the transient tests, the times to CHF detection ranged from 0.5 to 25.4 s. The steady-state CHF's for the 4-rod test sections were higher than those for the 7-rod test sections with respect to the bundle averaged flow conditions. The measured CHF's increased with decreasing the heated length and decreased with decreasing the P/D. Based on the local flow conditions obtained with the subchannel analysis code COBRA-IV-I, KfK correlation agreed with the CHF data within 20 %, while WSC-2, EPRI-B and W, EPRI-Columbia and Kattor correlations failed to give satisfactory agreements. Under flow reduction rates less than 6 %/s, no significant difference in the onset conditions of DNB (departure from nucleate boiling) was recognized between the steady-state and transient conditions. At flow reduction rates higher than 6 %/s, on the other hand, the DNB occurred earlier than the DNB time predicted with the steady-state experiments. (author)

  6. Dose-rate conversion factors for external exposure to photon and electron radiation from radionuclides occurring in routine releases from nuclear fuel cycle facilities

    International Nuclear Information System (INIS)

    Kocher, D.C.

    1980-01-01

    Dose-rate conversion factors for external exposure to photon and electron radiation are calculated for 240 radionuclides of potential importance in routine releases from nuclear fuel cycle facilities. Exposure modes considered are immersion in contaminated air, immersion in contaminated water, and irradiation from a contaminated ground surface. For each exposure mode, dose-rate conversion factors for photons and electrons are calculated for tissue-equivalent material at the body surface of an exposed individual. Dose-rate conversion factors for photons only are calculated for 22 body organs. (author)

  7. Operation of high rate microstrip gas chambers

    CERN Document Server

    Barr, A J; Bouclier, Roger; Capéans-Garrido, M; Dominik, Wojciech; Manzin, G; Million, Gilbert; Hoch, M; Ropelewski, Leszek; Sauli, Fabio; Sharma, A

    1996-01-01

    We describe recent measurements carried out in well controlled and reproducible conditions to help understanding the factors affecting the short and long term behaviour of Microstrip Gas Chambers. Special care has been taken concerning the gas purity and choice of materials used in the system and for the detectors construction. Detectors built on glasses with surface resistivity in the range $10^{13}-10^{15} \\Omega/\\Box$ have shown satisfactory performance as they do not show charging-up process at high rate and stand the large doses required for the future high luminosity experiments (~10 mC·cm-1·yr-1). Concerning the lifetime measurements, it has been observed that chambers manufactured on high-resistivity glass are far more susceptible of suffering ageing than detectors made on low resistivity, electron-conducting supports, independently of the metal used for the artwork (chromium or gold) at least in clean gas conditions. The successfully operation in the laboratory of detectors manufactured on diamond-...

  8. Study on Millimeter-Wave Vivaldi Rectenna and Arrays with High Conversion Efficiency

    Directory of Open Access Journals (Sweden)

    Guan-Nan Tan

    2016-01-01

    Full Text Available A novel Vivaldi rectenna operated at 35 GHz with high millimeter wave to direct current (MMW-to-DC conversion efficiency is presented and the arrays are investigated. The measured conversion efficiency is 51.6% at 35 GHz and the efficiency higher than 30% is from 33.2 GHz to 36.6 GHz when the input MMW power is 79.4 mW. The receiving Vivaldi antenna loaded with metamaterial units has a high gain of 10.4 dBi at 35 GHz. A SIW- (substrate integrated waveguide- to-microstrip transition is designed not only to integrate the antenna with the rectifying circuit directly but also to provide the DC bypass for the rectifying circuit. When the power density is 8.7 mW/cm2, the received MMW power of the antenna is 5.6 mW, and the maximum conversion efficiency of the rectenna element is 31.5%. The output DC voltage of the element is nearly the same as that of the parallel array and is about half of the series array. The DC power obtained by the 1 × 2 rectenna arrays is about two times as much as that of the element. The conversion efficiencies of the arrays are very close to that of the element. Large scale arrays could be expended for collecting more DC power.

  9. Consideration of wear rates at high velocity

    Science.gov (United States)

    Hale, Chad S.

    The development of the research presented here is one in which high velocity relative sliding motion between two bodies in contact has been considered. Overall, the wear environment is truly three-dimensional. The attempt to characterize three-dimensional wear was not economically feasible because it must be analyzed at the micro-mechanical level to get results. Thus, an engineering approximation was carried out. This approximation was based on a metallographic study identifying the need to include viscoplasticity constitutive material models, coefficient of friction, relationships between the normal load and velocity, and the need to understand wave propagation. A sled test run at the Holloman High Speed Test Track (HHSTT) was considered for the determination of high velocity wear rates. In order to adequately characterize high velocity wear, it was necessary to formulate a numerical model that contained all of the physical events present. The experimental results of a VascoMax 300 maraging steel slipper sliding on an AISI 1080 steel rail during a January 2008 sled test mission were analyzed. During this rocket sled test, the slipper traveled 5,816 meters in 8.14 seconds and reached a maximum velocity of 1,530 m/s. This type of environment was never considered previously in terms of wear evaluation. Each of the features of the metallography were obtained through micro-mechanical experimental techniques. The byproduct of this analysis is that it is now possible to formulate a model that contains viscoplasticity, asperity collisions, temperature and frictional features. Based on the observations of the metallographic analysis, these necessary features have been included in the numerical model, which makes use of a time-dynamic program which follows the movement of a slipper during its experimental test run. The resulting velocity and pressure functions of time have been implemented in the explicit finite element code, ABAQUS. Two-dimensional, plane strain models

  10. Motion Vector field improvement for picture rate conversion with reduced Halo

    NARCIS (Netherlands)

    Mertens, M.J.W.; Haan, de G.; Girod, B.; Bouman, C.A.; Steinbach, E.G.

    2001-01-01

    The quality of the interpolated images in picture rate upconversion is predominantly dependent on the accuracy of the motion vector fields. Block based MEs typically yield incorrect vectors in occlusion areas, which leads to an annoying halo in the upconverted video sequences. In the past we have

  11. High Data Rate Architecture (HiDRA)

    Science.gov (United States)

    Hylton, Alan; Raible, Daniel

    2016-01-01

    high-rate laser terminals. These must interface with the existing, aging data infrastructure. The High Data Rate Architecture (HiDRA) project is designed to provide networked store, carry, and forward capability to optimize data flow through both the existing radio frequency (RF) and new laser communications terminal. The networking capability is realized through the Delay Tolerant Networking (DTN) protocol, and is used for scheduling data movement as well as optimizing the performance of existing RF channels. HiDRA is realized as a distributed FPGA memory and interface controller that is itself controlled by a local computer running DTN software. Thus HiDRA is applicable to other arenas seeking to employ next-generation communications technologies, e.g. deep space. In this paper, we describe HiDRA and its far-reaching research implications.

  12. Application of the dose rate spectroscopy to the dose-to-curie conversion method using a NaI(Tl) detector

    International Nuclear Information System (INIS)

    JI, Young-Yong; Chung, Kun Ho; Kim, Chang-Jong; Kang, Mun Ja; Park, Sang Tae

    2015-01-01

    Dose rate spectroscopy is a very useful method to directly calculate the individual dose rate from the converted energy spectrum for the dose rate using the G-factor which is related to the used detector response function. A DTC conversion method for the estimation of the radioactivity based on the measured dose rate from the radioactive materials can then be modified into a simple equation using the dose rate spectroscopy. In order to make the method validation of the modified DTC conversion method, experimental verifications using a 3″φx3″ NaI(Tl) detector were conducted at the simple geometry of the point source located onto a detector and more complex geometries which mean the assay of the simulated radioactive material. In addition, the linearity about the results from the modified DTC conversion method was also estimated by increasing the distance between source positions and a detector to confirm the method validation in the energy, dose rate, and distance range of the gamma nuclides. - Highlights: • A modified DTC conversion method using the dose rate spectroscopy was established. • In-situ calibration factors were calculated from the MCNP simulation. • Radioactivities of the disk sources were accurately calculated using a modified DTC conversion method. • A modified DTC conversion method was applied to the assay of the radioactive material

  13. Matter effects on the flavor conversions of solar neutrinos and high-energy astrophysical neutrinos

    Science.gov (United States)

    Huang, Guo-yuan; Liu, Jun-Hao; Zhou, Shun

    2018-06-01

    Can we observe the solar eclipses in the neutrino light? In principle, this is possible by identifying the lunar matter effects on the flavor conversions of solar neutrinos when they traverse the Moon before reaching the detectors at the Earth. Unfortunately, we show that the lunar matter effects on the survival probability of solar 8B neutrinos are suppressed by an additional factor of 1.2%, compared to the day-night asymmetry. However, we point out that the matter effects on the flavor conversions of high-energy astrophysical neutrinos, when they propagate through the Sun, can be significant. Though the flavor composition of high-energy neutrinos can be remarkably modified, it is quite challenging to observe such effects even in the next-generation of neutrino telescopes.

  14. Catalytic oxidative conversion of cellulosic biomass to formic acid and acetic acid with exceptionally high yields

    KAUST Repository

    Zhang, Jizhe

    2014-09-01

    Direct conversion of raw biomass materials to fine chemicals is of great significance from both economic and ecological perspectives. In this paper, we report that a Keggin-type vanadium-substituted phosphomolybdic acid catalyst, namely H4PVMo11O40, is capable of converting various biomass-derived substrates to formic acid and acetic acid with high selectivity in a water medium and oxygen atmosphere. Under optimized reaction conditions, H4PVMo11O40 gave an exceptionally high yield of formic acid (67.8%) from cellulose, far exceeding the values achieved in previous catalytic systems. Our study demonstrates that heteropoly acids are generally effective catalysts for biomass conversion due to their strong acidities, whereas the composition of metal addenda atoms in the catalysts has crucial influence on the reaction pathway and the product selectivity. © 2013 Elsevier B.V.

  15. Conversion of wastelands into state ownership for the needs of high-rise construction

    Science.gov (United States)

    Ganebnykh, Elena

    2018-03-01

    High-rise construction in big cities faces the problem of land shortage in downtown areas. Audit of economic complexes showed a large volume of wastelands. The conversion of wastelands into state and municipal ownership helps in part to solve the problem of the lack of space for high-rise construction in the urban area in the format of infill construction. The article investigates the problem of the conversion of wastelands into state and municipal ownership. The research revealed no clear algorithm for converting wastelands into state and municipal ownership. To form a unified system for identifying such plots, a universal algorithm was developed to identify and convert ownerless immovable property into state or municipal ownership.

  16. Critical evaluation of high-temperature gas-cooled reactors applicable to coal conversion

    International Nuclear Information System (INIS)

    Spiewak, I.; Jones, J.E. Jr.; Rittenhouse, P.L.; DeStefano, J.R.; Delene, J.G.

    1975-12-01

    A critical review is presented of the technology and costs of very high-temperature gas-cooled reactors (VHTRs) applicable to nuclear coal conversion. Coal conversion processes suitable for coupling to reactors are described. Vendor concepts of the VHTR are summarized. The materials requirements as a function of process temperature in the range 1400 to 2000 0 F are analyzed. Components, environmental and safety factors, economics and nuclear fuel cycles are reviewed. It is concluded that process heat supply in the range 1400 to 1500 0 F could be developed with a high degree of assurance. Process heat at 1600 0 F would require considerably more materials development. While temperatures up to 2000 0 F appear to be attainable, considerably more research and risk were involved. A demonstration plant would be required as a step in the commercialization of the VHTR

  17. Photocathodes for High Repetition Rate Light Sources

    Energy Technology Data Exchange (ETDEWEB)

    Ben-Zvi, Ilan [Stony Brook Univ., NY (United States). Dept. of Physics and Astronomy. Center for Accelerator Science and Education

    2014-04-20

    This proposal brought together teams at Brookhaven National Laboratory (BNL), Lawrence Berkeley National Laboratory (LBNL) and Stony Brook University (SBU) to study photocathodes for high repetition rate light sources such as Free Electron Lasers (FEL) and Energy Recovery Linacs (ERL). Below details the Principal Investigators and contact information. Each PI submits separately for a budget through his corresponding institute. The work done under this grant comprises a comprehensive program on critical aspects of the production of the electron beams needed for future user facilities. Our program pioneered in situ and in operando diagnostics for alkali antimonide growth. The focus is on development of photocathodes for high repetition rate Free Electron Lasers (FELs) and Energy Recovery Linacs (ERLs), including testing SRF photoguns, both normal-­conducting and superconducting. Teams from BNL, LBNL and Stony Brook University (SBU) led this research, and coordinated their work over a range of topics. The work leveraged a robust infrastructure of existing facilities and the support was used for carrying out the research at these facilities. The program concentrated in three areas: a) Physics and chemistry of alkali-­antimonide cathodes (BNL – LBNL) b) Development and testing of a diamond amplifier for photocathodes (SBU -­ BNL) c) Tests of both cathodes in superconducting RF photoguns (SBU) and copper RF photoguns (LBNL) Our work made extensive use of synchrotron radiation materials science techniques, such as powder-­ and single-­crystal diffraction, x-­ray fluorescence, EXAFS and variable energy XPS. BNL and LBNL have many complementary facilities at the two light sources associated with these laboratories (NSLS and ALS, respectively); use of these will be a major thrust of our program and bring our understanding of these complex materials to a new level. In addition, CHESS at Cornell will be used to continue seamlessly throughout the NSLS dark period and

  18. Rate of revisions or conversion after bariatric surgery over 10 years in the state of New York.

    Science.gov (United States)

    Altieri, Maria S; Yang, Jie; Nie, Lizhou; Blackstone, Robin; Spaniolas, Konstantinos; Pryor, Aurora

    2018-04-01

    A primary measure of the success of a procedure is the whether or not additional surgery may be necessary. Multi-institutional studies regarding the need for reoperation after bariatric surgery are scarce. The purpose of this study is to evaluate the rate of revisions/conversions (RC) after 3 common bariatric procedures over 10 years in the state of New York. University Hospital, involving a large database in New York State. The Statewide Planning and Research Cooperative System database was used to identify all patients undergoing laparoscopic adjustable gastric banding (LAGB), sleeve gastrectomy (SG), and Roux-en-Y gastric bypass (RYGB) between 2004 and 2010. Patients were followed for RC to other bariatric procedures for at least 4 years (up to 2014). Multivariable cox proportional hazard regression analysis was performed to identify risk factors for additional surgery after each common bariatric procedure. Multivariable logistic regression was used to check the factors associated with having ≥2 follow-up procedures. There were 40,994 bariatric procedures with 16,444 LAGB, 22,769 RYGB, and 1781 SG. Rate of RC was 26.0% for LAGB, 9.8% for SG, and 4.9% for RYGB. Multiple RC ( = />2) were more common for LAGB (5.7% for LAGB, .5% for RYGB, and .2% for LSG). Band revision/replacements required further procedures compared with patients who underwent conversion to RYGB/SG (939 compared with 48 procedures). Majority of RC were not performed at initial institution (68.2% of LAGB patients, 75.9% for RYGB, 63.7% of SG). Risk factors for multiple procedures included surgery type, as LAGB was more likely to have multiple RC. Reoperation was common for LAGB, but less common for RYGB (4.9%) and SG (9.8%). RC rate are almost twice after SG than after RYGB. LAGB had the highest rate (5.7%) of multiple reoperations. Conversion was the procedure of choice after a failed LAGB. Copyright © 2018 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

  19. Highly-Efficient Thermoelectronic Conversion of Heat and Solar Radiation to Electric Power

    OpenAIRE

    Meir, Stefan

    2013-01-01

    Thermionic energy conversion has long been a candidate to convert solar radiation and the combustion heat of fossil fuels into electricity at high efficiencies. However, the formation of electron space charges has prevented the widespread use of the principle since its was first suggested in 1915. In this work, a novel mechanism to suppress the effects of the space charge was investigated: the acceleration of electrons in a special configuration of electric and magnetic fields. This work d...

  20. Highly integrated CO2 capture and conversion: Direct synthesis of cyclic carbonates from industrial flue gas

    KAUST Repository

    Barthel, Alexander; Saih, Youssef; Gimenez, Michel; Pelletier, Jeremie; Kü hn, Fritz Elmar; D´ Elia, Valerio; Basset, Jean-Marie

    2016-01-01

    Robust and selective catalytic systems based on early transition metal halides (Y, Sc, Zr) and organic nucleophiles were found able to quantitatively capture CO2 from diluted streams via formation of hemicarbonate species and to convert it to cyclic organic carbonates under ambient conditions. This observation was exploited in the direct and selective chemical fixation of flue gas CO2 collected from an industrial exhaust, affording high degrees of CO2 capture and conversion.

  1. Highly integrated CO2 capture and conversion: Direct synthesis of cyclic carbonates from industrial flue gas

    KAUST Repository

    Barthel, Alexander

    2016-02-08

    Robust and selective catalytic systems based on early transition metal halides (Y, Sc, Zr) and organic nucleophiles were found able to quantitatively capture CO2 from diluted streams via formation of hemicarbonate species and to convert it to cyclic organic carbonates under ambient conditions. This observation was exploited in the direct and selective chemical fixation of flue gas CO2 collected from an industrial exhaust, affording high degrees of CO2 capture and conversion.

  2. Brachytherapy treatment with high dose rate

    International Nuclear Information System (INIS)

    Santana Rodriguez, Sergio Marcelino; Rodriguez Rodriguez, Lissi Lisbet; Ciscal Chiclana, Onelio Alberto

    2009-01-01

    Retrospectively analyze results and prognostic factors of cervical cancer patients treated with radio concomitant cisplatin-based chemotherapy, radiation therapy combined modality. Methods: From January 2003 to December 2007, 198 patients with invasive cervical cancer were treated at the Oncology Department of Hospital Robau Celestino Hernandez (brachytherapy performed at INOR). The most common age group was 31 to 40 years. The histology in squamous cell carcinoma accounted for 84.3% of cases. The treatment consisted of external pelvic irradiation and vaginal brachytherapy, high dose rate. Concomitant chemotherapy consisted of cisplatin 40 mg/m2 weekly with a maximum of 70 mg for 5 weeks. Results: 66.2% of patients completed 5 cycles of chemotherapy. The median overall survival was 39 months, overall survival, disease-free survival and survival free of locoregional recurrence at 5 years of 78%, 76% and 78.6% respectively .. We found that clinical stage, histological type (adenocarcinoma worst outcome) were statistically related to level of response. Conclusions: Treatment with external pelvic radiation, brachytherapy and concurrent weekly cisplatin in patients with stage IIIB cervical cancer is feasible in the Chilean public health system, well tolerated and results comparable to international literature. (Author)

  3. Interpersonal Movement Synchrony Responds to High- and Low-Level Conversational Constraints

    Directory of Open Access Journals (Sweden)

    Alexandra Paxton

    2017-07-01

    Full Text Available Much work on communication and joint action conceptualizes interaction as a dynamical system. Under this view, dynamic properties of interaction should be shaped by the context in which the interaction is taking place. Here we explore interpersonal movement coordination or synchrony—the degree to which individuals move in similar ways over time—as one such context-sensitive property. Studies of coordination have typically investigated how these dynamics are influenced by either high-level constraints (i.e., slow-changing factors or low-level constraints (i.e., fast-changing factors like movement. Focusing on nonverbal communication behaviors during naturalistic conversation, we analyzed how interacting participants' head movement dynamics were shaped simultaneously by high-level constraints (i.e., conversation type; friendly conversations vs. arguments and low-level constraints (i.e., perceptual stimuli; non-informative visual stimuli vs. informative visual stimuli. We found that high- and low-level constraints interacted non-additively to affect interpersonal movement dynamics, highlighting the context sensitivity of interaction and supporting the view of joint action as a complex adaptive system.

  4. Experimental determination of the kinetic conversion rate of gaseous tritium into HTO

    International Nuclear Information System (INIS)

    Gulden, W.; Guenot, J.; Djerassi, H.; Clerc, H.

    1986-09-01

    To assess the impact of atmospheric tritium releases from a fusion plant to the environment, the dose to man usually is determined under the conservative assumption that all tritium is released in the more dangerous oxide form. To quantify this overprediction, experiments are presently being performed by CEA. Oxidation of tritium gas by soil and subsequent resuspension of HTO from soil to atmosphere is one of them. First results have been obtained by CEA on the kinetics of HTO resuspension from contaminated soils. Immediately after contamination, the fraction of the deposited activity which is resuspended to atmosphere is in the range of 1% to 5% per hour. This resuspension rate then decreases more or less slowly with time, depending on specific conditions

  5. An integrated CMOS high data rate transceiver for video applications

    International Nuclear Information System (INIS)

    Liang Yaping; Sun Lingling; Che Dazhi; Liang Cheng

    2012-01-01

    This paper presents a 5 GHz CMOS radio frequency (RF) transceiver built with 0.18 μm RF-CMOS technology by using a proprietary protocol, which combines the new IEEE 802.11n features such as multiple-in multiple-out (MIMO) technology with other wireless technologies to provide high data rate robust real-time high definition television (HDTV) distribution within a home environment. The RF frequencies cover from 4.9 to 5.9 GHz: the industrial, scientific and medical (ISM) band. Each RF channel bandwidth is 20 MHz. The transceiver utilizes a direct up transmitter and low-IF receiver architecture. A dual-quadrature direct up conversion mixer is used that achieves better than 35 dB image rejection without any on chip calibration. The measurement shows a 6 dB typical receiver noise figure and a better than 33 dB transmitter error vector magnitude (EVM) at −3 dBm output power. (semiconductor integrated circuits)

  6. HE CONVERSION OF THE EFFICIENCY OF LABOR, RESPECTIVELY OF LABOR PRODUCTIVITY IN THE ECONOMIC AND COMMERCIAL RATE OF RETURN

    Directory of Open Access Journals (Sweden)

    Constantin CĂRUNTU

    2010-12-01

    Full Text Available Generally, an activity is considered to be efficient if the production implies low costs or if the revenues from selling the products on the market outweigh the expenditures that were made to achieve them. Labor productivity as an efficiency indicator of a production process represents an expression of the relationship between effect (products, services and effort (work means, labor force, work items. Through the labor productivity conversion in rates of return (economic and commercial is determined an evolution and an influence on these rates, driving the company’s own efforts to innovate, produce and harness goods, works and services with maximum utility, efficiency and competitiveness services. The aim of this paper is to highlight the work efficiency, respectively the labor productivity detached from the factorial context in the trade and economic rates of return. The introduction presents some general aspects referring to labor productivity, then it will be presented and discussed the analytical methods used in the process of reflecting the labor productivity in the rates of return, the results analysis, and at the end of this paper it will be presented some conclusions based on the study case. The expected results consist in identifying the mechanisms by which labor efficiency is converted into the company’s economic and financial performance.

  7. An optimized rapid bisulfite conversion method with high recovery of cell-free DNA.

    Science.gov (United States)

    Yi, Shaohua; Long, Fei; Cheng, Juanbo; Huang, Daixin

    2017-12-19

    Methylation analysis of cell-free DNA is a encouraging tool for tumor diagnosis, monitoring and prognosis. Sensitivity of methylation analysis is a very important matter due to the tiny amounts of cell-free DNA available in plasma. Most current methods of DNA methylation analysis are based on the difference of bisulfite-mediated deamination of cytosine between cytosine and 5-methylcytosine. However, the recovery of bisulfite-converted DNA based on current methods is very poor for the methylation analysis of cell-free DNA. We optimized a rapid method for the crucial steps of bisulfite conversion with high recovery of cell-free DNA. A rapid deamination step and alkaline desulfonation was combined with the purification of DNA on a silica column. The conversion efficiency and recovery of bisulfite-treated DNA was investigated by the droplet digital PCR. The optimization of the reaction results in complete cytosine conversion in 30 min at 70 °C and about 65% of recovery of bisulfite-treated cell-free DNA, which is higher than current methods. The method allows high recovery from low levels of bisulfite-treated cell-free DNA, enhancing the analysis sensitivity of methylation detection from cell-free DNA.

  8. High mitogenomic evolutionary rates and time dependency.

    NARCIS (Netherlands)

    Subramanian, S.; Denver, D.R.; Millar, C.D.; Heupink, T.; Aschrafi, A.; Emslie, S.D.; Baroni, C.; Lambert, D.M.

    2009-01-01

    Using entire modern and ancient mitochondrial genomes of Adelie penguins (Pygoscelis adeliae) that are up to 44000 years old, we show that the rates of evolution of the mitochondrial genome are two to six times greater than those estimated from phylogenetic comparisons. Although the rate of

  9. Rationale for continuing R&D in direct coal conversion to produce high quality transportation fuels

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, R.D.; McIlvried, H.G. [Burns and Roe Services Corp., Pittsburgh, PA (United States); Gray, D. [Mitre Corp, McLean, VA (United States)] [and others

    1995-12-31

    For the foreseeable future, liquid hydrocarbon fuels will play a significant role in the transportation sector of both the United States and the world. Factors favoring these fuels include convenience, high energy density, and the vast existing infrastructure for their production and use. At present the U.S. consumes about 26% of the world supply of petroleum, but this situation is expected to change because of declining domestic production and increasing competition for imports from countries with developing economies. A scenario and time frame are developed in which declining world resources will generate a shortfall in petroleum supply that can be allieviated in part by utilizing the abundant domestic coal resource base. One option is direct coal conversion to liquid transportation fuels. Continued R&D in coal conversion technology will results in improved technical readiness that can significantly reduce costs so that synfuels can compete economically in a time frame to address the shortfall.

  10. Ultra-broadband and high-efficiency polarization conversion metasurface with multiple plasmon resonance modes

    International Nuclear Information System (INIS)

    Dong Guo-Xiang; Xia Song; Li Wei; Zhang An-Xue; Xu Zhuo; Wei Xiao-Yong; Shi Hong-Yu

    2016-01-01

    In this paper, we present a novel metasurface design that achieves a high-efficiency ultra-broadband cross polarization conversion. The metasurface is composed of an array of unit resonators, each of which combines an H-shaped structure and two rectangular metallic patches. Different plasmon resonance modes are excited in unit resonators and allow the polarization states to be manipulated. The bandwidth of the cross polarization converter is 82% of the central frequency, covering the range from 15.7 GHz to 37.5 GHz. The conversion efficiency of the innovative new design is higher than 90%. At 14.43 GHz and 40.95 GHz, the linearly polarized incident wave is converted into a circularly polarized wave. (paper)

  11. High lactic acid and fructose production via Mn2+-mediated conversion of inulin by Lactobacillus paracasei.

    Science.gov (United States)

    Petrov, Kaloyan; Popova, Luiza; Petrova, Penka

    2017-06-01

    Lactobacillus paracasei DSM 23505 is able to produce high amounts of lactic acid (LA) by simultaneous saccharification and fermentation (SSF) of inulin. Aiming to obtain the highest possible amounts of LA and fructose, the present study is devoted to evaluate the impact of bivalent metal ions on the process of inulin conversion. It was shown that Mn 2+ strongly increases the activity of the purified key enzyme β-fructosidase. In vivo, batch fermentation kinetics revealed that the high Mn 2+ concentrations accelerated inulin hydrolysis by raise of the inulinase activity, and increased sugars conversion to LA through enhancement of the whole glycolytic flux. The highest LA concentration and yield were reached by addition of 15 mM Mn 2+ -151 g/L (corresponding to 40% increase) and 0.83 g/g, respectively. However, the relative quantification by real-time reverse transcription assay showed that the presence of Mn 2+ decreases the expression levels of fosE gene encoding β-fructosidase. Contrariwise, the full exclusion of metal ions resulted in fosE gene expression enhancement, blocked fructose transport, and hindered fructose conversion thus leading to huge fructose accumulation. During fed-batch with optimized medium and fermentation parameters, the fructose content reached 35.9% (w/v), achieving yield of 467 g fructose from 675 g inulin containing chicory flour powder (0.69 g/g). LA received in course of the batch fermentation and fructose gained by the fed-batch are the highest amounts ever obtained from inulin, thus disclosing the key role of Mn 2+ as a powerful tool to guide inulin conversion to targeted bio-chemicals.

  12. Beneficial Effect of Conversion to Belatacept in Kidney-Transplant Patients with a Low Glomerular-Filtration Rate

    Directory of Open Access Journals (Sweden)

    Julie Belliere

    2014-01-01

    Full Text Available Belatacept has been found to be efficient at preserving good kidney function in maintenance kidney-transplant patients. Herein, we report on the use of belatacept as a rescue therapy for two kidney-transplant patients presenting with severe adverse events after treatment with calcineurin inhibitors (CNIs and mammalian target-of-rapamycin (mTOR inhibitors. Two kidney-transplant patients developed severely impaired kidney function after receiving CNIs. The use of everolimus was associated with severe angioedema. Belatacept was then successfully used to improve kidney function in both cases, even though estimated glomerular-filtration rate before conversion was <20 mL/min. These case reports show that belatacept can be used as a rescue therapy, even if kidney function is very low in kidney-transplant patients who cannot tolerate CNIs and/or mTOR inhibitors.

  13. Tunable catalytic properties of bi-functional mixed oxides in ethanol conversion to high value compounds

    Energy Technology Data Exchange (ETDEWEB)

    Ramasamy, Karthikeyan K.; Gray, Michel J.; Job, Heather M.; Smith, Colin D.; Wang, Yong

    2016-04-10

    tA highly versatile ethanol conversion process to selectively generate high value compounds is pre-sented here. By changing the reaction temperature, ethanol can be selectively converted to >C2alcohols/oxygenates or phenolic compounds over hydrotalcite derived bi-functional MgO–Al2O3cata-lyst via complex cascade mechanism. Reaction temperature plays a role in whether aldol condensationor the acetone formation is the path taken in changing the product composition. This article containsthe catalytic activity comparison between the mono-functional and physical mixture counterpart to thehydrotalcite derived mixed oxides and the detailed discussion on the reaction mechanisms.

  14. Cheetah: A high frame rate, high resolution SWIR image camera

    Science.gov (United States)

    Neys, Joel; Bentell, Jonas; O'Grady, Matt; Vermeiren, Jan; Colin, Thierry; Hooylaerts, Peter; Grietens, Bob

    2008-10-01

    A high resolution, high frame rate InGaAs based image sensor and associated camera has been developed. The sensor and the camera are capable of recording and delivering more than 1700 full 640x512pixel frames per second. The FPA utilizes a low lag CTIA current integrator in each pixel, enabling integration times shorter than one microsecond. On-chip logics allows for four different sub windows to be read out simultaneously at even higher rates. The spectral sensitivity of the FPA is situated in the SWIR range [0.9-1.7 μm] and can be further extended into the Visible and NIR range. The Cheetah camera has max 16 GB of on-board memory to store the acquired images and transfer the data over a Gigabit Ethernet connection to the PC. The camera is also equipped with a full CameralinkTM interface to directly stream the data to a frame grabber or dedicated image processing unit. The Cheetah camera is completely under software control.

  15. Nitrogen conversion during rapid pyrolysis of coal and petroleum coke in a high-frequency furnace

    International Nuclear Information System (INIS)

    Yuan, Shuai; Zhou, Zhi-jie; Li, Jun; Wang, Fu-chen

    2012-01-01

    Highlights: ► Use a high-frequency furnace to study N-conversion during rapid pyrolysis of coal. ► Scarcely reported N-conversion during rapid pyrolysis of petroleum coke was studied. ► Both of NH 3 and HCN can be formed directly from coal during rapid pyrolysis. ► NH 3 –N yields are higher than HCN–N yields in most conditions. ► NH 3 –N yields of petroleum coke increase with temperature and no HCN detected. -- Abstract: Rapid pyrolysis of three typical Chinese coals, lignite from Inner Mongolia, bituminous from Shenfu coalfield, and anthracite from Guizhou, as well as a petroleum coke were carried out in a drop-style high-frequency furnace. The reactor was induction coil heated and had a very small high-temperature zone, which could restrain secondary conversions of nitrogen products. The effects of temperature and coal rank on conversions of fuel-N to primary nitrogen products (char-N, HCN–N, NH 3 –N and (tar + N 2 )–N) have been investigated. The results showed that, the increasing temperature reduced the yields of char-N and promoted the conversion of fuel-N to N 2 . Char-N yields increased, while volatile-N yields decreased as the coal rank increased. In most of the conditions, NH 3 –N yields were higher than HCN–N yields during rapid pyrolysis of coal. In the case of petroleum coke, NH 3 –N yields increased gradually with the increasing temperature, but no HCN was detected. We argue that NH 3 –N can be formed directly through the primary pyrolysis without secondary reactions. Although volatile-N yields of lignite were higher than those of bituminous, yields of (HCN + NH 3 )–N in volatile-N of lignite were lower than those of bituminous. While the (HCN + NH 3 )–N yields of anthracite were the lowest of the three coals. Both of the (HCN + NH 3 )–N yields and (HCN + NH 3 )–N proportions in volatile-N of petroleum coke were lower than the three coals.

  16. High thermal efficiency x-ray energy conversion scheme for advanced fusion reactors

    International Nuclear Information System (INIS)

    Quimby, D.C.; Taussig, R.T.; Hertzberg, A.

    1977-01-01

    This paper reports on a new radiation energy conversion scheme which appears to be capable of producing electricity from the high quality x-ray energy with efficiencies of 60 to 70 percent. This new reactor concept incorporates a novel x-ray radiation boiler and a new thermal conversion device known as an energy exchanger. The low-Z first walls of the radiation boiler are semi-transparent to x-rays, and are kept cool by incoming working fluid, which is subsequently heated to temperatures of 2000 to 3000 0 K in the interior of the boiler by volumetric x-ray absorption. The radiation boiler may be a compact part of the reactor shell since x-rays are readily absorbed in high-Z materials. The energy exchanger transfers the high-temperature working fluid energy to a lower temperature gas which drives a conventional turbine. The overall efficiency of the cycle is characterized by the high temperature of the working fluid. The high thermal efficiencies which appear achievable with this cycle would make an otherwise marginal advanced fusion reactor into an attractive net power producer. The operating principles, initial conceptual design, and engineering problems of the radiation boiler and thermal cycle are presented

  17. Thick sputtered tantalum coatings for high-temperature energy conversion applications

    Energy Technology Data Exchange (ETDEWEB)

    Stelmakh, Veronika, E-mail: stelmakh@mit.edu; Peykov, Daniel; Chan, Walker R.; Senkevich, Jay J.; Joannopoulos, John D.; Soljačić, Marin; Celanovic, Ivan [Institute for Soldier Nanotechnologies, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Castillo, Robert; Coulter, Kent; Wei, Ronghua [Materials Engineering Department, Southwest Research Institute, San Antonio, Texas 78238 (United States)

    2015-11-15

    Thick sputtered tantalum (Ta) coatings on polished Inconel were investigated as a potential replacement for bulk refractory metal substrates used for high-temperature emitters and absorbers in thermophotovoltaic energy conversion applications. In these applications, high-temperature stability and high reflectance of the surface in the infrared wavelength range are critical in order to sustain operational temperatures and reduce losses due to waste heat. The reflectance of the coatings (8 and 30 μm) was characterized with a conformal protective hafnia layer as-deposited and after one hour anneals at 700, 900, and 1100 °C. To further understand the high-temperature performance of the coatings, the microstructural evolution was investigated as a function of annealing temperature. X-ray diffraction was used to analyze the texture and residual stress in the coatings at four reflections (220, 310, 222, and 321), as-deposited and after anneal. No significant changes in roughness, reflectance, or stress were observed. No delamination or cracking occurred, even after annealing the coatings at 1100 °C. Overall, the results of this study suggest that the thick Ta coatings are a promising alternative to bulk substrates and pave the way for a relatively low-cost and easily integrated platform for nanostructured devices in high-temperature energy conversion applications.

  18. All-Optical Wavelength Conversion of a High-Speed RZ-OOK Signal in a Silicon Nanowire

    DEFF Research Database (Denmark)

    Hu, Hao; Ji, Hua; Galili, Michael

    2011-01-01

    All-optical wavelength conversion of a 320 Gb/s line-rate RZ-OOK signal is demonstrated based on four-wave mixing in a 3.6 mm long silicon nanowire. Bit error rate measurements validate the performance within FEC limits.......All-optical wavelength conversion of a 320 Gb/s line-rate RZ-OOK signal is demonstrated based on four-wave mixing in a 3.6 mm long silicon nanowire. Bit error rate measurements validate the performance within FEC limits....

  19. X-ray conversion efficiency of high-Z hohlraum wall materials for indirect drive ignition

    International Nuclear Information System (INIS)

    Dewald, E. L.; Rosen, M.; Glenzer, S. H.; Suter, L. J.; Neumayer, P.; Landen, O. L.; Girard, F.; Jadaud, J. P.; Wagon, F.; Huser, G.; Schein, J.; Constantin, C.

    2008-01-01

    The conversion efficiency of 351 nm laser light to soft x rays (0.1-5 keV) was measured for Au, U, and high Z mixture ''cocktails'' used as hohlraum wall materials in indirect drive fusion experiments. For the spherical targets in a direct drive geometry, flattop laser pulses and laser smoothing with phase plates are employed to achieve constant and uniform laser intensities of 10 14 and 10 15 W/cm 2 over the target surface that are relevant for the future ignition experiments at the National Ignition Facility [G. H. Miller, E. I. Moses, and C. R. Wuest, Nucl. Fusion 44, 228 (2004)]. The absolute time and spectrally resolved radiation flux is measured with a multichannel soft x-ray power diagnostic. The conversion efficiency is then calculated by dividing the measured x-ray power by the incident laser power from which the measured laser backscattering losses are subtracted. After ∼0.5 ns, the time resolved x-ray conversion efficiency reaches a slowly increasing plateau of 95% at 10 14 W/cm 2 laser intensity and of 80% at 10 15 W/cm 2 . The M-band flux (2-5 keV) is negligible at 10 14 W/cm 2 reaching ∼1% of the total x-ray flux for all target materials. In contrast, the M-band flux is significant and depends on the target material at 10 15 W/cm 2 laser intensity, reaching values between 10% of the total flux for U and 27% for Au. LASNEX simulations [G. B. Zimmerman and W. L. Kruer, Comm. Plasma Phys. Contr. Fusion 2, 51 (1975)] show good agreement in conversion efficiency and radiated spectra with data when using XSN atomic physics model and a flux limiter of 0.15, but they underestimate the generated M-band flux.

  20. X-ray Conversion Efficiency of high-Z hohlraum wall materials for indirect drive ignition

    International Nuclear Information System (INIS)

    Dewald, E.; Rosen, M.; Glenzer, S.H.; Suter, L.J.; Girard, F.; Jadaud, J.P.; Schein, J.; Constantin, C.G.; Neumayer, P.; Landen, O.

    2008-01-01

    We measure the conversion efficiency of 351 nm laser light to soft x-rays (0.1-5 keV) for Au, U and high Z mixtures 'cocktails' used for hohlraum wall materials in indirect drive ICF. We use spherical targets in a direct drive geometry, flattop laser pulses and laser smoothing with phase plates to achieve constant and uniform laser intensities of 10 14 and 10 15 W/cm 2 over the target surface that are relevant for the future ignition experiments on NIF. The absolute time and spectrally-resolved radiation flux is measured with a multichannel soft x-ray power diagnostic. The conversion efficiency is then calculated by dividing the measured x-ray power by the incident laser power from which the measured laser backscattering losses is subtracted. After ∼0.5 ns, the time resolved x-ray conversion efficiency reaches a slowly increasing plateau of 95% at 10 14 W/cm 2 laser intensity and of 80% at 10 15 W/cm 2 . The M-band flux (2-5 keV) is negligible at 10 14 W/cm 2 reaching ∼1% of the total x-ray flux for all target materials. In contrast, the M-band flux is significant and depends on the target material at 10 15 W/cm 2 laser intensity, reaching values between 10% of the total flux for U and 27% for Au. Our LASNEX simulations show good agreement in conversion efficiency and radiated spectra with data when using XSN atomic physics model and a flux limiter of 0.15, but they underestimate the generated M-band flux

  1. Ceramic high-rate timing RPCs

    International Nuclear Information System (INIS)

    Lopes, L.; Ferreira Marques, R.; Fonte, P.; Hennetier, L.; Pereira, A.; Sousa Correia, A.M.

    2006-01-01

    Following some previous work, we report here considerable improvements on the counting rate capability of timing RPCs by the use of ceramic electrodes with a resistivity of 10 9 Ω.cm. The X-ray sensitivity of the detector depends linearly on the counting rate with a slope of 9% per 100 kHz/cm 2 , free from charge depletion effects, while keeping a timing accuracy, measured with 511 keV synchronous photon pairs, around 90 ps σ up to 75 kHz/cm 2

  2. High conversion efficiency and high radiation resistance InP solar cells

    International Nuclear Information System (INIS)

    Yamamoto, Akio; Itoh, Yoshio; Yamaguchi, Masafumi

    1987-01-01

    The fabrication of homojunction InP solar cells has been studied using impurity thermal diffusion, organometallic vapor phase epitaxy (OMVPE) and liquid phase epitaxy (LPE), and is discussed in this paper. Conversion efficiencies exceeding 20 % (AM1.5) are attained. These are the most efficient results ever reported for InP cells, and are comparable to those for GaAs cells. Electron and γ-ray irradiation studies have also been conducted for fabricated InP cells. The InP cells were found to have higher radiation resistance than GaAs cells. Through these studies, it has been demonstrated that the InP cells have excellent potential for space application. (author)

  3. High Temperature Fusion Reactor Cooling Using Brayton Cycle Based Partial Energy Conversion

    Science.gov (United States)

    Juhasz, Albert J.; Sawicki, Jerzy T.

    2003-01-01

    For some future space power systems using high temperature nuclear heat sources most of the output energy will be used in other than electrical form, and only a fraction of the total thermal energy generated will need to be converted to electrical work. The paper describes the conceptual design of such a partial energy conversion system, consisting of a high temperature fusion reactor operating in series with a high temperature radiator and in parallel with dual closed cycle gas turbine (CCGT) power systems, also referred to as closed Brayton cycle (CBC) systems, which are supplied with a fraction of the reactor thermal energy for conversion to electric power. Most of the fusion reactor's output is in the form of charged plasma which is expanded through a magnetic nozzle of the interplanetary propulsion system. Reactor heat energy is ducted to the high temperature series radiator utilizing the electric power generated to drive a helium gas circulation fan. In addition to discussing the thermodynamic aspects of the system design the authors include a brief overview of the gas turbine and fan rotor-dynamics and proposed bearing support technology along with performance characteristics of the three phase AC electric power generator and fan drive motor.

  4. Controlling Solid–Liquid Conversion Reactions for a Highly Reversible Aqueous Zinc–Iodine Battery

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Huilin; Li, Bin; Mei, Donghai; Nie, Zimin; Shao, Yuyan; Li, Guosheng; Li, Xiaohong S.; Han, Kee Sung; Muller, Karl T.; Sprenkle, Vincent L.; Liu, Jun

    2017-10-30

    Aqueous rechargeable batteries are desirable for many energy storage applications due to their low cost and high safety. However, low capacity and short cycle life are the significant obstacles to their practical applications. Here, we demonstrate a highly reversible aqueous zinc-iodine battery using encapsulated iodine in microporous active carbon fibers (ACFs) as cathode materials through the rational control of solid-liquid conversion reactions. The experiments and density function theory (DFT) calculations were employed to investigate the effects of solvents and properties of carbon hosts, e.g. pore size, surface chemistries, on the adsorption of iodine species. The rational manipulation of the competition between the adsorption in carbon and solvation in electrolytes for iodine species is responsible for the high reversibility and cycling stability. The zinc-iodine batteries deliver a high capacity of 180 mAh g-1 at 1C and a stable cycle life over 3000 cycles with ~90% capacity retention as well as negligible self-discharge. We believe the principles for stabilizing the zinc-iodine system could provide new insight into conversion systems such as Li-S systems.

  5. Design of a Highly Stable, High-Conversion-Efficiency, Optical Parametric Chirped-Pulse Amplification System with Good Beam Quality

    International Nuclear Information System (INIS)

    Guardalben, M.J.; Keegan, J.; Waxer, L.J.; Bagnoud, V.; Begishev, I.A.; Puth, J.; Zuegel, J.D.

    2003-01-01

    OAK B204 An optical parametric chirped-pulse amplifier (OPCPA) design that provides 40% pump-to-signal conversion efficiency and over-500-mJ signal energy at 1054 nm for front-end injection into a Nd:glass amplifier chain is presented. This OPCPA system is currently being built as the prototype front end for the OMEGA EP (extended performance) laser system at the University of Rochester's Laboratory for Laser Energetics. Using a three-dimensional spatial and temporal numerical model, several design considerations necessary to achieve high conversion efficiency, good output stability, and good beam quality are discussed. The dependence of OPCPA output on the pump beam's spatiotemporal shape and the relative size of seed and pump beams is described. This includes the effects of pump intensity modulation and pump-signal walk-off. The trade-off among efficiency, stability, and low output beam intensity modulation is discussed

  6. High-power waveguide resonator second harmonic device with external conversion efficiency up to 75%

    Science.gov (United States)

    Stefszky, M.; Ricken, R.; Eigner, C.; Quiring, V.; Herrmann, H.; Silberhorn, C.

    2018-06-01

    We report on a highly efficient waveguide resonator device for the production of 775 nm light using a titanium indiffused LiNbO3 waveguide resonator. When scanning the resonance, the device produces up to 110 mW of second harmonic power with 140 mW incident on the device—an external conversion efficiency of 75%. The cavity length is also locked, using a Pound–Drever–Hall type locking scheme, involving feedback to either the cavity temperature or the laser frequency. With laser frequency feedback, a stable output power of approximately 28 mW from a 52 mW pump is seen over one hour.

  7. Evaluation of some resonance self-shielding procedures employed in high conversion light water reactor design

    International Nuclear Information System (INIS)

    Patino, N.E.; Abbate, M.J.; Sbaffoni, M.M.

    1990-01-01

    The procedures employed in the treatment of the resonance shielding effect have been identified as one of the causes of the large discrepancies found in the neutronic calculation of high conversion light water reactors (HCLWRs), indicating the need for a revision of the self-shielding procedures employed. In this work some well known techniques applied in HCLWR self-shielding calculations are evaluated; the study involves the comparison of methods for the generation of group constants, the analysis of the impact of considering some isotopes as infinitely diluted and the evaluation of the usual approximations utilized for the treatment of heterogeneities

  8. Analysis of proinsulin and its conversion products by reversed-phase high-performance liquid chromatography

    DEFF Research Database (Denmark)

    Linde, S; Welinder, B S; Nielsen, Jens Høiriis

    1993-01-01

    . Most mammals produce a single insulin, but in rodents two non-allelic insulin genes are expressed. There is an inverse ratio between the two insulins in rats and mice, the reason for this being unknown. It has been suggested that differences in transcription, translation (biosynthesis) and...... PIM (intact proinsulin or its intermediates) has been incompletely determined. Studies of the biosynthesis of proinsulins and their conversion with the purpose of revealing some of these points depend on accessible reversed-phase high-performance liquid chromatographic (RP-HPLC) analyses capable...

  9. Efficient high-peak-power and high-repetition-rate eye-safe laser using an intracavity KTP OPO

    International Nuclear Information System (INIS)

    Guo, J; Jiao, Z X; Wang, B; He, G Y

    2015-01-01

    An efficient high-peak-power and high-repetition-rate intracavity KTP optical parametric oscillator pumped by a Q-switched Nd:YVO 4 laser is demonstrated. We achieved 1.5 W output power of 1.5 μm at 10 kHz repetition rate with the pulse duration of 6 ns. The maximum peak power of 25 kW and the maximum pulse energy of 150 μJ have been obtained. The maximum conversion efficiency of 9.5% is achieved with respect to a laser diode power of 10.5 W. (paper)

  10. Transition to high rate aerospace NDI processes

    Science.gov (United States)

    Vanderheiden, Bert; Thomson, Clint; Ivakhnenko, Igor; Garner, Chuck

    2018-04-01

    With the rapidly expanding use of carbon fiber composite materials in military and commercial aircraft, processes to manufacture and inspect the structural components must evolve to ensure economic viability. Inspection techniques which were developed to inspect products produced at a rate of one or two structures a month are not fast or flexible enough to inspect more than 8500 parts per month. This presentation describes the evolution of phased array ultrasonic inspection systems to provide the increased rate capacity, the flexibility to accommodate multiple unique designs, and the ability to rapidly adjust to product design changes. The paper will describe how system developments were made in response to new programs resulting in a much less expensive, higher degree of accuracy, increased flexibility, and lower cycle time inspections.

  11. High exposure rate hardware ALARA plan

    International Nuclear Information System (INIS)

    Nellesen, A.L.

    1996-10-01

    This as low as reasonably achievable review provides a description of the engineering and administrative controls used to manage personnel exposure and to control contamination levels and airborne radioactivity concentrations. HERH waste is hardware found in the N-Fuel Storage Basin, which has a contact dose rate greater than 1 R/hr and used filters. This waste will be collected in the fuel baskets at various locations in the basins

  12. Why Are Real Interest Rates So High?

    OpenAIRE

    Zvi Bodie; Alex Kane; Robert L. McDonald

    1983-01-01

    This paper applies the Capital Asset Pricing Model to help explain the anomalous behavior of real interest rates during the last several years. Specifically,we are able to show that the increased volatility of bond prices since the change in Federal Reserve operating procedure in October 1979 has substantially increased the required real risk premium on long term bonds. We also consider and reject the possibility that increased risk alone accounts for the recent increase in the short-term rea...

  13. High conversion Th-U{sup 233} fuel assembly for current generation of PWRs

    Energy Technology Data Exchange (ETDEWEB)

    Baldova, D.; Fridman, E. [Reactor Safety Div., Helmholtz-Zentrum Dresden-Rossendorf, POB 510119, Dresden, 01314 (Germany)

    2012-07-01

    This paper presents a preliminary design of a high conversion Th-U{sup 233} fuel assembly applicable for current generation of Pressurized Water Reactor (PWRs). The considered fuel assembly has a typical 17 x 17 PWR lattice. However in order to increase the conversion of Th{sup 232} to U{sup 233}, the assembly was subdivided into the two regions called seed and blanket. The central seed region has a higher than blanket U{sup 233} content and acts as a neutron source for the peripheral blanket region. The latest acts as a U{sup 233} breeder. While the seed fuel pins have a standard dimensions the blanket fuel radius was increased in order to reduce the moderation and to facilitate the resonance neutron absorption in blanket Th{sup 232}. The U{sup 233} content in the seed and blanket regions was optimized to achieve maximal initial to discharged fissile inventory ratio (FIR) taking into account the target fuel cycle length of 12 months with 3-batch reloading scheme. In this study the neutronic calculations were performed on the fuel assembly level using Helios deterministic lattice transport code. The fuel cycle length and the core k{sub eff} were estimated by applying the Non Linear Reactivity Model. The applicability of the HELIOS code for the analysis of the Th-based high conversion designs was confirmed with the help of continuous-energy Monte-Carlo code SERPENT. The results of optimization studies show that for the heterogeneous seed and blanket (SB) fuel assembly the FIR of about 0.95 can be achieved. (authors)

  14. Conversational Repair in School-Aged Children with High-Functioning Autism

    Directory of Open Access Journals (Sweden)

    Pei-Mei Lu

    2015-12-01

    Full Text Available The main purpose of this study was to investigate the conversational repair skills of Mandarin Chinese-speaking children with high-functioning autism (HFA as compared with those of typically developing children (TD. Ten school-aged children (age 9 to 12 with HFA were recruited and matched against ten TD children in the control group based on age, gender, and verbal intelligence level. During three different conversation situations (free talk, story picture description, play, an examiner engineered 9 episodes of communicative breakdowns. Each consisted of a stacked series of three prompts for responding to requests for clarification (RQCLs (i.e.‘What?’, ‘I don’t understand’, ‘I still don’t know’. Verbal responses to each RQCL were then coded for further analyses. The results showed that (1 In response to the stacked series RQCLs, children with HFA were similar to the control group children in evidencing repetition, revision, and addition types of repair. Furthermore, children with HFA showed fewer cue type of repair and more inappropriate type of repair than TD group. (2For both groups, the pattern of responding over the series of RQCLs was similar in varying the repetition and revision types of repair strategies. However, the pattern in the addition, cue, and inappropriate types of repair strategies were different. Children with HFA were significantly more likely to respond to an RQCL with an inappropriate response than the language and age-matched controls. It is suggested that teachers and parents could facilitate the conversational repair skills of children with high-functioning autism by offering them opportunities to manage different types of communicative breakdowns.

  15. Wavelength conversion devices

    DEFF Research Database (Denmark)

    Mikkelsen, Benny; Durhuus, Terji; Jørgensen, Carsten

    1996-01-01

    system requirements. The ideal wavelength converter should be transparent to the bit rate and signal format and provide an unchirped output signal with both a high extinction ratio and a large signal-to-noise ratio. It should allow conversion to both shorter and longer wavelengths with equal performance...

  16. Generation of µW level plateau harmonics at high repetition rate.

    Science.gov (United States)

    Hädrich, S; Krebs, M; Rothhardt, J; Carstens, H; Demmler, S; Limpert, J; Tünnermann, A

    2011-09-26

    The process of high harmonic generation allows for coherent transfer of infrared laser light to the extreme ultraviolet spectral range opening a variety of applications. The low conversion efficiency of this process calls for optimization or higher repetition rate intense ultrashort pulse lasers. Here we present state-of-the-art fiber laser systems for the generation of high harmonics up to 1 MHz repetition rate. We perform measurements of the average power with a calibrated spectrometer and achieved µW harmonics between 45 nm and 61 nm (H23-H17) at a repetition rate of 50 kHz. Additionally, we show the potential for few-cycle pulses at high average power and repetition rate that may enable water-window harmonics at unprecedented repetition rate. © 2011 Optical Society of America

  17. Fission product model for lattice calculation of high conversion boiling water reactor

    International Nuclear Information System (INIS)

    Iijima, S.; Yoshida, T.; Yamamoto, T.

    1988-01-01

    A high precision fission product model for boiling water reactor (BWR) lattice calculation was developed, which consists of 45 nuclides to be treated explicitly and one nonsaturating pseudo nuclide. This model is applied to a high conversion BWR lattice calculation code. From a study based on a three-energy-group calculation of fission product poisoning due to full fission products and explicitly treated nuclides, the multigroup capture cross sections and the effective fission yields of the pseudo nuclide are determined, which do not depend on fuel types or reactor operating conditions for a good approximation. Apart from nuclear data uncertainties, the model and the derived pseudo nuclide constants would predict the fission product reactivity within an error of 0.1% Δk at high burnup

  18. High readmission rate after heart valve surgery

    DEFF Research Database (Denmark)

    Sibilitz, K L; Berg, S K; Thygesen, L C

    2015-01-01

    investigated. RESULTS: After valve surgery, the self-reported health was lower (Short Form-36 (SF-36) Physical Component Scale (PCS): 44.5 vs. 50.6 and Mental Component Scale (MCS): 51.9 vs. 55.0, pClinical signs......BACKGROUND: After heart valve surgery, knowledge on long-term self-reported health status and readmission is lacking. Thus, the optimal strategy for out-patient management after surgery remains unclear. METHODS: Using a nationwide survey with linkage to Danish registers with one year follow-up, we...... included all adults 6-12months after heart valve surgery irrespective of valve procedure, during Jan-June 2011 (n=867). Participants completed a questionnaire regarding health-status (n=742), and answers were compared with age- and sex-matched healthy controls. Readmission rates and mortality were...

  19. High PEC conversion efficiencies from CuSe film electrodes modified with metalloporphyrin/polyethylene matrices

    International Nuclear Information System (INIS)

    Zyoud, Ahed; Al-Kerm, Rola S.; Al-Kerm, Rana S.; Waseem, Mansur; Mohammed, H.S. Helal; Park, DaeHoon; Campet, Guy; Sabli, Nordin; Hilal, Hikmat S.

    2015-01-01

    Enhancement of hole-transfer across CuSe electrode/liquid junction can be facilitated by coating with metalloporphyrin complexes embedded inside polyethylene matrices. - Highlights: • CuSe films were electrochemically deposited onto FTO/Glass • Annealing CuSe film electrodes enhanced PEC characteristics • PEC characteristics were further enhanced by metalloporphyrin/polyethylene matrices, yielding ∼15% efficiency • Matrix behavior as charge transfer mediator enhanced electrode conversion efficiency and stability - Abstract: Electrodeposited CuSe film electrodes have been prepared onto FTO/glass by a facile method based on earlier methods described for other systems. The films were characterized, modified by annealing and further characterized. The films were then modified by coating with tetra(-4-pyridyl) pophyrinato-manganese (MnTPyP) complexes embedded inside commercial polyethylene (PE) matrices. The effects of modifications on different film properties, such as X-ray diffraction (XRD) patterns, surface morphology, photoluminescence (PL) spectra and electronic absorption spectra were investigated. Compared with other thin film electrode systems, very high photoelectrochemical (PEC) conversion efficiency values have been observed here. Pre-annealing the CuSe films at 150°C for 2 h, followed by attaching the MnTPyP/PE matrices remarkably enhanced their PEC characteristics. The conversion efficiency was significantly enhanced, from less than 1.0% to more than 15%. Fill factor (FF) was also enhanced from ∼30% to ∼80%. Values of open-circuit potential (V OC ) and short-circuit current (J SC ) were significantly enhanced. While annealing affects uniformity, particle inter-connection and surface texture of the CuSe films, the MnTPyP complex species behaves as an additional charge-transfer mediator across the film/electrolyte junction. Optimization of PEC characteristics, using different deposition times, different annealing temperatures, different

  20. Anti-corrosive Conversion Coating on Aluminium Alloys Using High Temperature Steam

    DEFF Research Database (Denmark)

    Din, Rameez Ud; Jellesen, Morten Stendahl; Ambat, Rajan

    or convert to a functional conversion coating. In the last several decades chromate conversion coating (CrCCs) have been the most common conversion coatings used for aluminium alloys. Due to the toxicity of the hexavalent chrome, however, environmental friendly alternatives to CrCCs have been investigated...

  1. High dose rate brachytherapy source measurement intercomparison.

    Science.gov (United States)

    Poder, Joel; Smith, Ryan L; Shelton, Nikki; Whitaker, May; Butler, Duncan; Haworth, Annette

    2017-06-01

    This work presents a comparison of air kerma rate (AKR) measurements performed by multiple radiotherapy centres for a single HDR 192 Ir source. Two separate groups (consisting of 15 centres) performed AKR measurements at one of two host centres in Australia. Each group travelled to one of the host centres and measured the AKR of a single 192 Ir source using their own equipment and local protocols. Results were compared to the 192 Ir source calibration certificate provided by the manufacturer by means of a ratio of measured to certified AKR. The comparisons showed remarkably consistent results with the maximum deviation in measurement from the decay-corrected source certificate value being 1.1%. The maximum percentage difference between any two measurements was less than 2%. The comparisons demonstrated the consistency of well-chambers used for 192 Ir AKR measurements in Australia, despite the lack of a local calibration service, and served as a valuable focal point for the exchange of ideas and dosimetry methods.

  2. First-principles method for calculating the rate constants of internal-conversion and intersystem-crossing transitions.

    Science.gov (United States)

    Valiev, R R; Cherepanov, V N; Baryshnikov, G V; Sundholm, D

    2018-02-28

    A method for calculating the rate constants for internal-conversion (k IC ) and intersystem-crossing (k ISC ) processes within the adiabatic and Franck-Condon (FC) approximations is proposed. The applicability of the method is demonstrated by calculation of k IC and k ISC for a set of organic and organometallic compounds with experimentally known spectroscopic properties. The studied molecules were pyrromethene-567 dye, psoralene, hetero[8]circulenes, free-base porphyrin, naphthalene, and larger polyacenes. We also studied fac-Alq 3 and fac-Ir(ppy) 3 , which are important molecules in organic light emitting diodes (OLEDs). The excitation energies were calculated at the multi-configuration quasi-degenerate second-order perturbation theory (XMC-QDPT2) level, which is found to yield excitation energies in good agreement with experimental data. Spin-orbit coupling matrix elements, non-adiabatic coupling matrix elements, Huang-Rhys factors, and vibrational energies were calculated at the time-dependent density functional theory (TDDFT) and complete active space self-consistent field (CASSCF) levels. The computed fluorescence quantum yields for the pyrromethene-567 dye, psoralene, hetero[8]circulenes, fac-Alq 3 and fac-Ir(ppy) 3 agree well with experimental data, whereas for the free-base porphyrin, naphthalene, and the polyacenes, the obtained quantum yields significantly differ from the experimental values, because the FC and adiabatic approximations are not accurate for these molecules.

  3. CONVERSION OF FOREIGN COMPANIES ACCOUNTS IN THE ACCOUNT CONSOLIDATION PROCESS IN ROMANIA UNDER THE CLOSING RATE METHOD

    Directory of Open Access Journals (Sweden)

    Mariana BANUTA

    2017-12-01

    Full Text Available The article approaches a topical theme of debate both in the professional academic environment and especially in the economic practice, i.e. the manner of converting the accounts of foreign companies in the account consolidation process, in Romania. We analyse the conditions of applying the accounting regulations related to the consolidation of accounts, in Romania, focusing on the manner of converting the accounts of the foreign companies according to Order no. 1802/2014 approving the accounting regulations on individual annual financial statements and consolidated annual financial statements and to the International Financial Reporting Standards (IFRS. We focused on the presentation of the practical method of applying the conversion of the accounts of the foreign companies according to the closing rate method, because irrespective of the accounting referential applied by the parent company for consolidation, this method occurs in the pre-consolidation stage, if the group leader has affiliates abroad, and the individual financial statements of the companies in the consolidation perimeter have different disclosure currencies.

  4. High-deposition-rate ceramics synthesis

    Energy Technology Data Exchange (ETDEWEB)

    Allendorf, M.D.; Osterheld, T.H.; Outka, D.A. [Sandia National Laboratories, Livermore, CA (United States)] [and others

    1995-05-01

    Parallel experimental and computational investigations are conducted in this project to develop validated numerical models of ceramic synthesis processes. Experiments are conducted in the High-Temperature Materials Synthesis Laboratory in Sandia`s Combustion Research Facility. A high-temperature flow reactor that can accommodate small preforms (1-3 cm diameter) generates conditions under which deposition can be observed, with flexibility to vary both deposition temperature (up to 1500 K) and pressure (as low as 10 torr). Both mass spectrometric and laser diagnostic probes are available to provide measurements of gas-phase compositions. Experiments using surface analytical techniques are also applied to characterize important processes occuring on the deposit surface. Computational tools developed through extensive research in the combustion field are employed to simulate the chemically reacting flows present in typical industrial reactors. These include the CHEMKIN and Surface-CHEMKIN suites of codes, which permit facile development of complex reaction mechanisms and vastly simplify the implementation of multi-component transport and thermodynamics. Quantum chemistry codes are also used to estimate thermodynamic and kinetic data for species and reactions for which this information is unavailable.

  5. Liquid Argon Calorimeter performance at High Rates

    CERN Document Server

    Seifert, F; The ATLAS collaboration

    2013-01-01

    The expected increase of luminosity at HL-LHC by a factor of ten with respect to LHC luminosities has serious consequences for the signal reconstruction, radiation hardness requirements and operations of the ATLAS liquid argon calorimeters in the endcap, respectively forward region. Small modules of each type of calorimeter have been built and exposed to a high intensity proton beam of 50 GeV at IHEP/Protvino. The beam is extracted via the bent crystal technique, offering the unique opportunity to cover intensities ranging from $10^6$ p/s up to $3\\cdot10^{11}$ p/s. This exceeds the deposited energy per time expected at HL-LHC by more than a factor of 100. The correlation between beam intensity and the read-out signal has been studied. The data show clear indications of pulse shape distortion due to the high ionization build-up, in agreement with MC expectations. This is also confirmed from the dependence of the HV currents on beam intensity.

  6. Toward High-Power Klystrons With RF Power Conversion Efficiency on the Order of 90%

    CERN Document Server

    Baikov, Andrey Yu; Syratchev, Igor

    2015-01-01

    The increase in efficiency of RF power generation for future large accelerators is considered a high priority issue. The vast majority of the existing commercial high-power RF klystrons operates in the electronic efficiency range between 40% and 55%. Only a few klystrons available on the market are capable of operating with 65% efficiency or above. In this paper, a new method to achieve 90% RF power conversion efficiency in a klystron amplifier is presented. The essential part of this method is a new bunching technique - bunching with bunch core oscillations. Computer simulations confirm that the RF production efficiency above 90% can be reached with this new bunching method. The results of a preliminary study of an L-band, 20-MW peak RF power multibeam klystron for Compact Linear Collider with the efficiency above 85% are presented.

  7. Parametric studies for the nuclear design of high-conversion pressurized water reactors

    International Nuclear Information System (INIS)

    Axmann, J.; Oldekop, W.

    1987-01-01

    Undermoderated high-conversion pressurized water reactors with steel canning tubes offer the possibility of high burnup together with a comparatively low consumption of fissionable material; however, they require a relatively large inventory of fissionable material. The effects of different fuel compositions upon the specific consumption of fissionable material are investigated for a fixed burnup and moderator-to-fuel volume ratios varying between 0.5 and 2.0. Moreover, the required inventory of fissionable material is determined and the influence on the costs of electric power generation is shown. Further investigations deal with the neutron-physical effects of decreasing fuel rod diameters and the influence of differing steel additives. It appears that the parasitic neutron absorption by alloying constituents depends on the moderation level in a non-uniform manner and that the contribution of the fissionable material to the electric power generation costs is rather independent of the moderator-to-fuel volume ratio. (orig.) [de

  8. Type I parametric down conversion of highly focused Gaussian beams in finite length crystals

    International Nuclear Information System (INIS)

    Jeronimo-Moreno, Yasser; Jáuregui, R

    2014-01-01

    This paper presents a study of the correlations in wave vector space of photon pairs generated by type I spontaneous parametric down conversion using a Gaussian pump beam. The analysis covers both moderate focused and highly focused regimes, paying special attention to the angular spectrum and the conditional angular spectrum. Simple analytic expressions are derived that allow a detailed study of the dependence of these spectra on the waist of the source and the length of the nonlinear crystal. These expressions are in good agreement with numerical expectations and reported experimental results. They are used to make a systematic search of optimization parameters that improve the feasibility of using highly focused Gaussian beams to generate idler and signal photons with predetermined mean values and spread of their transverse wave vectors. (papers)

  9. Potential for efficient frequency conversion at high average power using solid state nonlinear optical materials

    International Nuclear Information System (INIS)

    Eimerl, D.

    1985-01-01

    High-average-power frequency conversion using solid state nonlinear materials is discussed. Recent laboratory experience and new developments in design concepts show that current technology, a few tens of watts, may be extended by several orders of magnitude. For example, using KD*P, efficient doubling (>70%) of Nd:YAG at average powers approaching 100 KW is possible; and for doubling to the blue or ultraviolet regions, the average power may approach 1 MW. Configurations using segmented apertures permit essentially unlimited scaling of average power. High average power is achieved by configuring the nonlinear material as a set of thin plates with a large ratio of surface area to volume and by cooling the exposed surfaces with a flowing gas. The design and material fabrication of such a harmonic generator are well within current technology

  10. Modeling of the dynamics of wind to power conversion including high wind speed behavior

    DEFF Research Database (Denmark)

    Litong-Palima, Marisciel; Bjerge, Martin Huus; Cutululis, Nicolaos Antonio

    2016-01-01

    This paper proposes and validates an efficient, generic and computationally simple dynamic model for the conversion of the wind speed at hub height into the electrical power by a wind turbine. This proposed wind turbine model was developed as a first step to simulate wind power time series...... for power system studies. This paper focuses on describing and validating the single wind turbine model, and is therefore neither describing wind speed modeling nor aggregation of contributions from a whole wind farm or a power system area. The state-of-the-art is to use static power curves for the purpose...... of power system studies, but the idea of the proposed wind turbine model is to include the main dynamic effects in order to have a better representation of the fluctuations in the output power and of the fast power ramping especially because of high wind speed shutdowns of the wind turbine. The high wind...

  11. Barriers to high conversion operations in an ebullated bed unit -- Relationship between sedimentation and operability

    Energy Technology Data Exchange (ETDEWEB)

    Sherwood, D. [Criterion Catalysts Company L.P., Houston, TX (United States)

    2000-07-01

    Ebullated-Bed (EB) catalytic processes are high temperature, high pressure residue hydrocrackers, which transform sour feeds into light, sweet products. EB processes typically involve one or more trains, with one, two, or three EB reactors in series. The key to operating any EB process is to control the 'sediment' which tends to increase with increasing level of conversion. Sediment problems are generally attributed to the catalyst. While this is true in some cases, there are certain problems that occur regardless of the catalyst used, whereas in some situations sediments from the EB process can actually be controlled by the catalyst. This paper describes two typical sedimentation patterns; one in which the sediment increases, and another in which sediment decreases as the EB products move through the recovery section. The benefits of sediment control are illustrated for the latter sedimentation pattern.

  12. Rate and Predictors of the Conversion of Abstracts Presented at the Canadian Cardiovascular Congress Scientific Meetings to Full Peer-Reviewed Publications

    DEFF Research Database (Denmark)

    Abuzeid, Wael; Fosbøl, Emil Loldrup; Fosbøl, Philip Loldrup

    2013-01-01

    The rate of conversion of abstracts presented at scientific meetings into peer-reviewed published manuscripts is an important metric for medical societies, because it facilitates translation of scientific knowledge into practice. We determined the rate and predictors of conversion of scientific...... abstracts presented at the Canadian Cardiovascular Congress (CCC) from 2006 to 2010 into peer-reviewed article publications within 2 years of their initial presentation. Using a previously validated computer algorithm, we searched the International Statistical Institute Web of Science to identify peer...

  13. Brayton Power Conversion Unit Tested: Provides a Path to Future High-Power Electric Propulsion Missions

    Science.gov (United States)

    Mason, Lee S.

    2003-01-01

    Closed-Brayton-cycle conversion technology has been identified as an excellent candidate for nuclear electric propulsion (NEP) power conversion systems. Advantages include high efficiency, long life, and high power density for power levels from about 10 kWe to 1 MWe, and beyond. An additional benefit for Brayton is the potential for the alternator to deliver very high voltage as required by the electric thrusters, minimizing the mass and power losses associated with the power management and distribution (PMAD). To accelerate Brayton technology development for NEP, the NASA Glenn Research Center is developing a low-power NEP power systems testbed that utilizes an existing 2- kWe Brayton power conversion unit (PCU) from previous solar dynamic technology efforts. The PCU includes a turboalternator, a recuperator, and a gas cooler connected by gas ducts. The rotating assembly is supported by gas foil bearings and consists of a turbine, a compressor, a thrust rotor, and an alternator on a single shaft. The alternator produces alternating-current power that is rectified to 120-V direct-current power by the PMAD unit. The NEP power systems testbed will be utilized to conduct future investigations of operational control methods, high-voltage PMAD, electric thruster interactions, and advanced heat rejection techniques. The PCU was tested in Glenn s Vacuum Facility 6. The Brayton PCU was modified from its original solar dynamic configuration by the removal of the heat receiver and retrofitting of the electrical resistance gas heater to simulate the thermal input of a steady-state nuclear source. Then, the Brayton PCU was installed in the 3-m test port of Vacuum Facility 6, as shown. A series of tests were performed between June and August of 2002 that resulted in a total PCU operational time of about 24 hr. An initial test sequence on June 17 determined that the reconfigured unit was fully operational. Ensuing tests provided the operational data needed to characterize PCU

  14. High power densities from high-temperature material interactions. [in thermionic energy conversion and metallic fluid heat pipes

    Science.gov (United States)

    Morris, J. F.

    1981-01-01

    Thermionic energy conversion (TEC) and metallic-fluid heat pipes (MFHPs), offering unique advantages in terrestrial and space energy processing by virtue of operating on working-fluid vaporization/condensation cycles that accept great thermal power densities at high temperatures, share complex materials problems. Simplified equations are presented that verify and solve such problems, suggesting the possibility of cost-effective applications in the near term for TEC and MFHP devices. Among the problems discussed are: the limitation of alkali-metal corrosion, protection against hot external gases, external and internal vaporization, interfacial reactions and diffusion, expansion coefficient matching, and creep deformation.

  15. Development of a Novel Bidirectional DC/DC Converter Topology with High Voltage Conversion Ratio for Electric Vehicles and DC-Microgrids

    Directory of Open Access Journals (Sweden)

    Ching-Ming Lai

    2016-05-01

    Full Text Available The main objective of this paper was to study a bidirectional direct current to direct current converter (BDC topology with a high voltage conversion ratio for electric vehicle (EV batteries connected to a dc-microgrid system. In this study, an unregulated level converter (ULC cascaded with a two-phase interleaved buck-boost charge-pump converter (IBCPC is introduced to achieve a high conversion ratio with a simpler control circuit. In discharge state, the topology acts as a two-stage voltage-doubler boost converter to achieve high step-up conversion ratio (48 V to 385 V. In charge state, the converter acts as two cascaded voltage-divider buck converters to achieve high voltage step-down conversion ratio (385 V to 48 V. The features, operation principles, steady-state analysis, simulation and experimental results are made to verify the performance of the studied novel BDC. Finally, a 500 W rating prototype system is constructed for verifying the validity of the operation principle. Experimental results show that highest efficiencies of 96% and 95% can be achieved, respectively, in charge and discharge states.

  16. Bioreactors for lignocellulose conversion into fermentable sugars for production of high added value products.

    Science.gov (United States)

    Liguori, Rossana; Ventorino, Valeria; Pepe, Olimpia; Faraco, Vincenza

    2016-01-01

    Lignocellulosic biomasses derived from dedicated crops and agro-industrial residual materials are promising renewable resources for the production of fuels and other added value bioproducts. Due to the tolerance to a wide range of environments, the dedicated crops can be cultivated on marginal lands, avoiding conflict with food production and having beneficial effects on the environment. Besides, the agro-industrial residual materials represent an abundant, available, and cheap source of bioproducts that completely cut out the economical and environmental issues related to the cultivation of energy crops. Different processing steps like pretreatment, hydrolysis and microbial fermentation are needed to convert biomass into added value bioproducts. The reactor configuration, the operative conditions, and the operation mode of the conversion processes are crucial parameters for a high yield and productivity of the biomass bioconversion process. This review summarizes the last progresses in the bioreactor field, with main attention on the new configurations and the agitation systems, for conversion of dedicated energy crops (Arundo donax) and residual materials (corn stover, wheat straw, mesquite wood, agave bagasse, fruit and citrus peel wastes, sunflower seed hull, switchgrass, poplar sawdust, cogon grass, sugarcane bagasse, sunflower seed hull, and poplar wood) into sugars and ethanol. The main novelty of this review is its focus on reactor components and properties.

  17. Accuracy of cell calculation methods used for analysis of high conversion light water reactor lattice

    International Nuclear Information System (INIS)

    Jeong, Chang-Joon; Okumura, Keisuke; Ishiguro, Yukio; Tanaka, Ken-ichi

    1990-01-01

    Validation tests were made for the accuracy of cell calculation methods used in analyses of tight lattices of a mixed-oxide (MOX) fuel core in a high conversion light water reactor (HCLWR). A series of cell calculations was carried out for the lattices referred from an international HCLWR benchmark comparison, with emphasis placed on the resonance calculation methods; the NR, IR approximations, the collision probability method with ultra-fine energy group. Verification was also performed for the geometrical modelling; a hexagonal/cylindrical cell, and the boundary condition; mirror/white reflection. In the calculations, important reactor physics parameters, such as the neutron multiplication factor, the conversion ratio and the void coefficient, were evaluated using the above methods for various HCLWR lattices with different moderator to fuel volume ratios, fuel materials and fissile plutonium enrichments. The calculated results were compared with each other, and the accuracy and applicability of each method were clarified by comparison with continuous energy Monte Carlo calculations. It was verified that the accuracy of the IR approximation became worse when the neutron spectrum became harder. It was also concluded that the cylindrical cell model with the white boundary condition was not so suitable for MOX fuelled lattices, as for UO 2 fuelled lattices. (author)

  18. Ultra-broadband and high-efficiency polarization conversion metasurface with multiple plasmon resonance modes

    Science.gov (United States)

    Dong, Guo-Xiang; Shi, Hong-Yu; Xia, Song; Li, Wei; Zhang, An-Xue; Xu, Zhuo; Wei, Xiao-Yong

    2016-08-01

    In this paper, we present a novel metasurface design that achieves a high-efficiency ultra-broadband cross polarization conversion. The metasurface is composed of an array of unit resonators, each of which combines an H-shaped structure and two rectangular metallic patches. Different plasmon resonance modes are excited in unit resonators and allow the polarization states to be manipulated. The bandwidth of the cross polarization converter is 82% of the central frequency, covering the range from 15.7 GHz to 37.5 GHz. The conversion efficiency of the innovative new design is higher than 90%. At 14.43 GHz and 40.95 GHz, the linearly polarized incident wave is converted into a circularly polarized wave. Project supported by the National Natural Science Foundation of China (Grant Nos. 61471292, 61331005, 61471388, 51277012, 41404095, and 61501365), the 111 Project, China (Grant No. B14040), the National Basic Research Program of China (Grant No. 2015CB654602), and the China Postdoctoral Science Foundation ( Grant No. 2015M580849).

  19. In situ generation of highly dispersed metal nanoparticles on two-dimensional layered SiO2 by topotactic structure conversion and their superior catalytic activity

    Science.gov (United States)

    Chen, Zhe; Jia, Da-Shuang; Zhou, Yue; Hao, Jiang; Liang, Yu; Cui, Zhi-Min; Song, Wei-Guo

    2018-03-01

    Metal nanoparticles such as Ag, Cu and Fe are effective catalysts for many reactions, whereas a facile method to prepare metal nanoparticles with high uniformed dispersion is still desirable. Herein, the topotactic structure conversion of layered silicate, RUB-15, was utilized to support metal nanoparticles. Through simple ion-exchange and following calcination step, metal nanoparticles were generated in situ inside the interlayer space of layered silica, and the topotactic structure conversion process assured nano-sized and highly uniformed dispersion of metal nanoparticles. The obtained Ag/SiO2 composite showed superior catalytic activity for the reduction of 4-nitrophenol (4-NP) and methylene blue (MB), with a rate constant as high as 0.0607 s-1 and 0.0778 s-1. The simple and universal synthesis method as well as high activity of the product composite endow the strategy good application prospect.

  20. Electrohydrodynamics: a high-voltage direct energy conversion process; L'electrohydrodynamique: Un procede de conversion directe d'energie a haute tension

    Energy Technology Data Exchange (ETDEWEB)

    Brun, S [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1967-04-15

    This analysis consists of a theoretical and practical study of a high-tension electrical power generator based on the Van de Graaff generator principle, the main difference being that the charges produced are transported by a gas in motion and not by a belt. The electrical and thermal properties of such a generator are studied, as well as the difficult problem of the production of the ionised particles used in the conversion. A certain number of results already published on this process for converting kinetic energy into electrical energy is given, as well as some possible applications in the field of space technology. (author) [French] Cette analyse est une etude theorique et pratique d'un generateur de puissance electrique a haute tension, base sur le principe du generateur Van de Graaff, la difference principale etant que les charges produites sont transportees pur un gaz en mouvement et non par une courroie. Les proprietes electriques et thermiques d'un tel generateur sont etudiees ainsi que le probleme delicat de la production des particules ionisees utilisees dans la conversion. Un certain nombre de resultats publies sur ce procede de conversion d'energie cinetique en energie electrique sont reproduits, ainsi que les applications possibles aux problemes spatiaux. (auteur)

  1. High School Graduation Rates:Alternative Methods and Implications

    OpenAIRE

    Jing Miao; Walt Haney

    2004-01-01

    The No Child Left Behind Act has brought great attention to the high school graduation rate as one of the mandatory accountability measures for public school systems. However, there is no consensus on how to calculate the high school graduation rate given the lack of longitudinal databases that track individual students. This study reviews literature on and practices in reporting high school graduation rates, compares graduation rate estimates yielded from alternative methods, and estimates d...

  2. Lysate of engineered Escherichia coli supports high-level conversion of glucose to 2,3-butanediol.

    Science.gov (United States)

    Kay, Jennifer E; Jewett, Michael C

    2015-11-01

    Cell-free metabolic engineering (CFME) is emerging as a powerful approach for the production of target molecules and pathway debugging. Unfortunately, high cofactor costs, limited cofactor and energy regeneration, and low volumetric productivities hamper the widespread use and practical implementation of CFME technology. To address these challenges, we have developed a cell-free system that harnesses ensembles of catalytic proteins prepared from crude lysates, or extracts, of cells to fuel highly active heterologous metabolic conversions. As a model pathway, we selected conversion of glucose to 2,3-butanediol (2,3-BD), a medium level commodity chemical with many industrial applications. Specifically, we engineered a single strain of Escherichia coli to express three pathway enzymes necessary to make meso-2,3-BD (m2,3-BD). We then demonstrated that lysates from this strain, with addition of glucose and catalytic amounts of cofactors NAD+ and ATP, can produce m2,3-BD. Endogenous glycolytic enzymes convert glucose to pyruvate, the starting intermediate for m2,3-BD synthesis. Strikingly, with no strain optimization, we observed a maximal synthesis rate of m2,3-BD of 11.3 ± 0.1 g/L/h with a theoretical yield of 71% (0.36 g m2,3-BD/g glucose) in batch reactions. Titers reached 82 ± 8 g/L m2,3-BD in a 30 h fed-batch reaction. Our results highlight the ability for high-level co-factor regeneration in cell-free lysates. Further, they suggest exciting opportunities to use lysate-based systems to rapidly prototype metabolic pathways and carry out molecular transformations when bioconversion yields (g product/L), productivities (g product/L/h), or cellular toxicity limit commercial feasibility of whole-cell fermentation. Copyright © 2015 International Metabolic Engineering Society. Published by Elsevier Inc. All rights reserved.

  3. High School Graduation Rates:Alternative Methods and Implications

    Directory of Open Access Journals (Sweden)

    Jing Miao

    2004-10-01

    Full Text Available The No Child Left Behind Act has brought great attention to the high school graduation rate as one of the mandatory accountability measures for public school systems. However, there is no consensus on how to calculate the high school graduation rate given the lack of longitudinal databases that track individual students. This study reviews literature on and practices in reporting high school graduation rates, compares graduation rate estimates yielded from alternative methods, and estimates discrepancies between alternative results at national, state, and state ethnic group levels. Despite the graduation rate method used, results indicate that high school graduation rates in the U.S. have been declining in recent years and that graduation rates for black and Hispanic students lag substantially behind those of white students. As to graduation rate method preferred, this study found no evidence that the conceptually more complex methods yield more accurate or valid graduation rate estimates than the simpler methods.

  4. Uranium conversion

    International Nuclear Information System (INIS)

    Oliver, Lena; Peterson, Jenny; Wilhelmsen, Katarina

    2006-03-01

    FOI, has performed a study on uranium conversion processes that are of importance in the production of different uranium compounds in the nuclear industry. The same conversion processes are of interest both when production of nuclear fuel and production of fissile material for nuclear weapons are considered. Countries that have nuclear weapons ambitions, with the intention to produce highly enriched uranium for weapons purposes, need some degree of uranium conversion capability depending on the uranium feed material available. This report describes the processes that are needed from uranium mining and milling to the different conversion processes for converting uranium ore concentrate to uranium hexafluoride. Uranium hexafluoride is the uranium compound used in most enrichment facilities. The processes needed to produce uranium dioxide for use in nuclear fuel and the processes needed to convert different uranium compounds to uranium metal - the form of uranium that is used in a nuclear weapon - are also presented. The production of uranium ore concentrate from uranium ore is included since uranium ore concentrate is the feed material required for a uranium conversion facility. Both the chemistry and principles or the different uranium conversion processes and the equipment needed in the processes are described. Since most of the equipment that is used in a uranium conversion facility is similar to that used in conventional chemical industry, it is difficult to determine if certain equipment is considered for uranium conversion or not. However, the chemical conversion processes where UF 6 and UF 4 are present require equipment that is made of corrosion resistant material

  5. The Effect of Minimum Wage Rates on High School Completion

    Science.gov (United States)

    Warren, John Robert; Hamrock, Caitlin

    2010-01-01

    Does increasing the minimum wage reduce the high school completion rate? Previous research has suffered from (1. narrow time horizons, (2. potentially inadequate measures of states' high school completion rates, and (3. potentially inadequate measures of minimum wage rates. Overcoming each of these limitations, we analyze the impact of changes in…

  6. Metallic metasurfaces for high efficient polarization conversion control in transmission mode.

    Science.gov (United States)

    Li, Tong; Hu, Xiaobin; Chen, Huamin; Zhao, Chen; Xu, Yun; Wei, Xin; Song, Guofeng

    2017-10-02

    A high efficient broadband polarization converter is an important component in integrated miniaturized optical systems, but its performances is often restricted by the material structures, metallic metasurfaces for polarization control in transmission mode never achieved efficiency above 0.5. Herein, we theoretically demonstrate that metallic metasurfaces constructed by thick cross-shaped particles can realize a high efficient polarization transformation over a broadband. We investigated the resonant properties of designed matesurfaces and found that the interaction between double FP cavity resonances and double bulk magnetic resonances is the main reason to generate a high transmissivity over a broadband. In addition, through using four resonances effect and tuning the anisotropic optical response, we realized a high efficient (> 0.85) quarter-wave plate at the wavelength range from 1175nm to 1310nm and a high efficient (> 0.9) half-wave plate at the wavelength range from 1130nm to 1230nm. The proposed polarization converters may have many potential applications in integrated polarization conversion devices and optical data storage systems.

  7. Consideration of ultra-high temperature nuclear heat sources for MHD conversion systems

    International Nuclear Information System (INIS)

    Holman, R.R.; Tobin, J.M.; Young, W.E.

    1975-01-01

    The nuclear technology reactors developed and tested in the Nuclear Engine Rocket Vehicle Application (NERVA) program operated with fuel exit gas temperatures in excess of 2600 K. This experience provided a significant ultra-high temperature technology base and design insight for commercial power applications. Design approaches to accommodate fission product retention and other key prevailing requirements are examined in view of the basic overriding functional requirements, and some interesting reconsiderations are suggested. Predicted overall system performance potentials for a 2000 K MHD conversion system and reactor parameter requirements are compared and related to existing technology status. Needed verification and development efforts are suggested. A reconsideration of basic design approaches is suggested that could open the door for immediate development of ultrahigh temperature nuclear heat sources for advanced energy systems

  8. Neutrino flavor conversions in high-density astrophysical and cosmological environments

    International Nuclear Information System (INIS)

    Saviano, Ninetta

    2014-03-01

    The topic of this thesis is the study of the neutrino flavor conversions in high-density environments: the supernovae and the the Early Universe. Remarkably, these represent the only two cases in which neutrinos themselves contribute to the ''background medium'' for their propagation, making their oscillations a non-linear phenomenon. In particular, in the dense supernova core, the neutrino-neutrino interactions can lead in some situations to surprising and counterintuitive collective phenomena, when the entire neutrino system oscillates coherently as a single collective mode. In this context, we have shown that during the early SN accretion phase (post-bounce times 10 -3 ) in order to suppress the sterile neutrino production and to find a better agreement between the cosmological and laboratory hints. Finally, we discuss the implications of our results on Big-Bang Nucleosynthesis and on the Cosmic Microwave Background from data measured by the Planck experiment.

  9. Computational screening of new inorganic materials for highly efficient solar energy conversion

    DEFF Research Database (Denmark)

    Kuhar, Korina

    2017-01-01

    in solar cells convert solar energy into electricity, and PC uses harvested energy to conduct chemical reactions, such as splitting water into oxygen and, more importantly, hydrogen, also known as the fuel of the future. Further progress in both PV and PC fields is mostly limited by the flaws in materials...... materials. In this work a high-throughput computational search for suitable absorbers for PV and PC applications is presented. A set of descriptors has been developed, such that each descriptor targets an important property or issue of a good solar energy conversion material. The screening study...... that we have access to. Despite the vast amounts of energy at our disposal, we are not able to harvest this solar energy efficiently. Currently, there are a few ways of converting solar power into usable energy, such as photovoltaics (PV) or photoelectrochemical generation of fuels (PC). PV processes...

  10. Core design options for high conversion BWRs operating in Th–233U fuel cycle

    International Nuclear Information System (INIS)

    Shaposhnik, Y.; Shwageraus, E.; Elias, E.

    2013-01-01

    Highlights: • BWR core operating in a closed self-sustainable Th– 233 U fuel cycle. • Seed blanket optimization that includes assembly size array and axial dimensions. • Fully coupled MC with fuel depletion and thermo-hydraulic feedback modules. • Thermal-hydraulic analysis includes MCPR observation. -- Abstract: Several options of fuel assembly design are investigated for a BWR core operating in a closed self-sustainable Th– 233 U fuel cycle. The designs rely on an axially heterogeneous fuel assembly structure consisting of a single axial fissile zone “sandwiched” between two fertile blanket zones, in order to improve fertile to fissile conversion ratio. The main objective of the study was to identify the most promising assembly design parameters, dimensions of fissile and fertile zones, for achieving net breeding of 233 U. The design challenge, in this respect, is that the fuel breeding potential is at odds with axial power peaking and the core minimum critical power ratio (CPR), hence limiting the maximum achievable core power rating. Calculations were performed with the BGCore system, which consists of the MCNP code coupled with fuel depletion and thermo-hydraulic feedback modules. A single 3-dimensional fuel assembly having reflective radial boundaries was modeled applying simplified restrictions on the maximum centerline fuel temperature and the CPR. It was found that axially heterogeneous fuel assembly design with a single fissile zone can potentially achieve net breeding, while matching conventional BWR core power rating under certain restrictions to the core loading pattern design

  11. Conversion rate of laparoscopic cholecystectomy after endoscopic retrograde cholangiography in the treatment of choledocholithiasis - Does the time interval matter?

    NARCIS (Netherlands)

    de Vries, A.; Donkervoort, S. C.; van Geloven, A. A. W.; Pierik, E. G. J. M.

    2005-01-01

    Background: Preceding endoscopic retrograde cholangiography (ERC) in patients with choledochocystolithiasis impedes laparoscopic cholecystectomy (LC) and increases risk of conversion. We studied the influence of time interval between ERC and LC on the course of LC. Methods: All patients treated for

  12. High regression rate, high density hybrid fuels, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR program will investigate high energy density novel nanofuels combined with high density binders for use with an N2O oxidizer. Terves has developed...

  13. Novel high efficient speed sensorless controller for maximum power extraction from wind energy conversion systems

    International Nuclear Information System (INIS)

    Fathabadi, Hassan

    2016-01-01

    Highlights: • Novel sensorless MPPT technique without drawbacks of other sensor/sensorless methods. • Tracking the actual MPP of WECSs, no tracking the MPP of their wind turbines. • Actually extracting the highest output power from WECSs. • Novel MPPT technique having the MPPT efficiency more than 98.5% for WECSs. • Novel MPPT technique having short convergence time for WECSs. - Abstract: In this study, a novel high accurate sensorless maximum power point tracking (MPPT) method is proposed. The technique tracks the actual maximum power point of a wind energy conversion system (WECS) at which maximum output power is extracted from the system, not the maximum power point of its wind turbine at which maximum mechanical power is obtained from the turbine, so it actually extracts the highest output power from the system. The technique only uses input voltage and current of the converter used in the system, and neither needs any speed sensors (anemometer and tachometer) nor has the drawbacks of other sensor/sensorless based MPPT methods. The technique has been implemented as a MPPT controller by constructing a WECS. Theoretical results, the technique performance, and its advantages are validated by presenting real experimental results. The real static-dynamic response of the MPPT controller is experimentally obtained that verifies the proposed MPPT technique high accurately extracts the highest instant power from wind energy conversion systems with the MPPT efficiency of more than 98.5% and a short convergence time that is only 25 s for the constructed system having a total inertia and friction coefficient of 3.93 kg m 2 and 0.014 N m s, respectively.

  14. Environmental impacts of genetic improvement of growth rate and feed conversion ratio in fish farming under rearing density and nitrogen output limitations

    NARCIS (Netherlands)

    Besson, M.; Aubin, J.; Komen, H.; Poelman, M.; Quillet, E.; Vandeputte, M.; Arendonk, Van J.A.M.; Boer, De I.J.M.

    2016-01-01

    Today, fish farming faces an increasing demand in fish products, but also various environmental challenges. Genetic improvement in growth rate and feed conversion ratio is known to be an efficient way to increase production and increase efficiency in fish farming. The environmental consequences

  15. Up-Conversion Intersystem Crossing Rates in Organic Emitters for Thermally Activated Delayed Fluorescence: Impact of the Nature of Singlet vs Triplet Excited States

    KAUST Repository

    Samanta, Pralok Kumar; Kim, Dongwook; Coropceanu, Veaceslav; Bredas, Jean-Luc

    2017-01-01

    The rates for up-conversion intersystem crossing (UISC) from the T1 state to the S1 state are calculated for a series of organic emitters with an emphasis on thermally activated delayed fluorescence (TADF) materials. Both the spin-orbit coupling

  16. Catalytic Conversion of Carbohydrates

    DEFF Research Database (Denmark)

    Osmundsen, Christian Mårup

    a renewable route to aromatics. The conversion of biomass by high temperature processes is a desirable prospect due to the high volumetric production rates which can be achieved, and the ability of these types of processes to convert a wide range of substrates. Current processes however typically have rather...... with the production of commodity chemicals from the most abundantly available renewable source of carbon, carbohydrates. The production of alkyl lactates by the Lewis acid catalyzed conversion of hexoses is an interesting alternative to current fermentation based processes. A range of stannosilicates were...... to be an efficient initial conversion step in the utilization of biomass for chemicals production. The shift from an oil based chemical industry to one based on renewable resources is bound to happen sooner or later, however the environmental problems associated with the burning of fossil resources means...

  17. R and D on the power conversion system for gas turbine high temperature reactors

    International Nuclear Information System (INIS)

    Takizuka, Takakazu; Takada, Shoji; Yan Xing; Kosugiyama, Shinichi; Katanishi, Shoji; Kunitomi, Kazuhiko

    2004-01-01

    JAERI is conducting R and D on the power conversion system of the GTHTR300 plant, in parallel with plant design work. The design of the power conversion system is based on a regenerative, non-intercooled, closed Brayton cycle with helium gas as the working fluid. A single-shaft, axial-flow turbo-compressor and a directly coupled electric generator run on magnetic bearings. Major R and D issues for the power conversion system are aerodynamic performance of the helium gas compressor, high load capacity magnetic bearings and performance of magnetic bearing supported rotor, and operability and controllability of the closed-cycle gas turbine system. Three test plans were set up to address theses issues, aiming at verifying the design of the GTHTR300 power conversion system and establishing key technologies of a closed-cycle helium gas turbine system. The compressor aerodynamic performance test is aiming at verifying the aerodynamic performance and design method of the helium compressor. A 1/3-scale, four-stage compressor test model and a helium gas loop were designed and fabricated. The model was designed to simulate the repeating stage flow, and at the same time have satisfactorily high machining precision, Reynolds number and measurement accuracy. The helium gas operating pressure is varied to investigate the effects of the Reynolds number on the efficiency and surge margin. Two sets of blades were fabricated to evaluate the effects of the end-wall over-camber angle. Test results will provide the basis for further improvement in the GTHTR300 compressor design. The magnetic bearing development test is aiming at developing the technology of the magnetic bearing supported rotor system. The test rig composed of 1/3-scale turbo-compressor and generator rotor models that are connected together by a flexible coupling. Each rotor models are supported by two radial magnetic bearings with a high load capacity that is about 1/10 of the GTHTR300 design. The rotor models were

  18. High-quality LaVO3 films as solar energy conversion material

    International Nuclear Information System (INIS)

    Zhang, Hai-Tian; Brahlek, Matthew; Ji, Xiaoyu; Lei, Shiming; Lapano, Jason

    2017-01-01

    Mott insulating oxides and their heterostructures have recently been identified as potential photovoltaic materials with favorable absorption properties and an intrinsic built-in electric field that can efficiently separate excited electron hole pairs. At the same time, they are predicted to overcome the Shockley-Queisser limit due to strong electron electron interaction present. Despite these premises a high concentration of defects commonly observed in Mott insulating films acting as recombination centers can derogate the photovoltaic conversion efficiency. With use of the self-regulated growth kinetics in hybrid molecular beam epitaxy, this obstacle can be overcome. High-quality, stoichiometric LaVO 3 films were grown with defect densities of in-gap states up to 2 orders of magnitude lower compared to the films in the literature, and a factor of 3 lower than LaVO 3 bulk single crystals. Photoconductivity measurements revealed a significant photoresponsivity increase as high as tenfold of stoichiometric LaVO 3 films compared to their nonstoichiometric counterparts. Furthermore, this work marks a critical step toward the realization of high-performance Mott insulator solar cells beyond conventional semiconductors.

  19. The american high school graduation rate : trends and levels

    OpenAIRE

    Heckman, James J.; LaFontaine, Paul A.

    2008-01-01

    This paper uses multiple data sources and a unified methodology to estimate the trends and levels of the U.S. high school graduation rate. Correcting for important biases that plague previous calculations, we establish that (a) the true high school graduation rate is substantially lower than the official rate issued by the National Center for Educational Statistics; (b) it has been declining over the past 40 years; (c) majority/minority graduation rate differentials are substantial and have n...

  20. Dye-sensitized solar cell module realized photovoltaic and photothermal highly efficient conversion via three-dimensional printing technology

    International Nuclear Information System (INIS)

    Huang Qi-Zhang; Zhu Yan-Qing; Shi Ji-Fu; Wang Lei-Lei; Zhong Liu-Wen; Xu Gang

    2017-01-01

    Three-dimensional (3D) printing technology is employed to improve the photovoltaic and photothermal conversion efficiency of dye-sensitized solar cell (DSC) module. The 3D-printed concentrator is optically designed and improves the photovoltaic efficiency of the DSC module from 5.48% to 7.03%. Additionally, with the 3D-printed microfluidic device serving as water cooling, the temperature of the DSC can be effectively controlled, which is beneficial for keeping a high photovoltaic conversion efficiency for DSC module. Moreover, the 3D-printed microfluidic device can realize photothermal conversion with an instantaneous photothermal efficiency of 42.1%. The integrated device realizes a total photovoltaic and photothermal conversion efficiency of 49% at the optimal working condition. (paper)

  1. Dye-sensitized solar cell module realized photovoltaic and photothermal highly efficient conversion via three-dimensional printing technology

    Institute of Scientific and Technical Information of China (English)

    Qi-Zhang Huang; Yan-Qing Zhu; Ji-Fu Shi; Lei-Lei Wang; Liu-Wen Zhong; Gang Xu

    2017-01-01

    Three-dimensional (3D) printing technology is employed to improve the photovoltaic and photothermal conversion efficiency of dye-sensitized solar cell (DSC) module.The 3D-printed concentrator is optically designed and improves the photovoltaic efficiency of the DSC module from 5.48% to 7.03%.Additionally,with the 3D-printed microfluidic device serving as water cooling,the temperature of the DSC can be effectively controlled,which is beneficial for keeping a high photovoltaic conversion efficiency for DSC module.Moreover,the 3D-printed microfluidic device can realize photothermal conversion with an instantaneous photothermal efficiency of 42.1%.The integrated device realizes a total photovoltaic and photothermal conversion efficiency of 49% at the optimal working condition.

  2. Large-video-display-format conversion

    NARCIS (Netherlands)

    Haan, de G.

    2000-01-01

    High-quality video-format converters apply motion estimation and motion compensation to prevent jitter resulting from picture-rate conversion, and aliasing due to de-interlacing, in sequences with motion. Although initially considered as too expensive, high-quality conversion is now economically

  3. Automatic conversational scene analysis in children with Asperger syndrome/high-functioning autism and typically developing peers.

    Science.gov (United States)

    Tavano, Alessandro; Pesarin, Anna; Murino, Vittorio; Cristani, Marco

    2014-01-01

    Individuals with Asperger syndrome/High Functioning Autism fail to spontaneously attribute mental states to the self and others, a life-long phenotypic characteristic known as mindblindness. We hypothesized that mindblindness would affect the dynamics of conversational interaction. Using generative models, in particular Gaussian mixture models and observed influence models, conversations were coded as interacting Markov processes, operating on novel speech/silence patterns, termed Steady Conversational Periods (SCPs). SCPs assume that whenever an agent's process changes state (e.g., from silence to speech), it causes a general transition of the entire conversational process, forcing inter-actant synchronization. SCPs fed into observed influence models, which captured the conversational dynamics of children and adolescents with Asperger syndrome/High Functioning Autism, and age-matched typically developing participants. Analyzing the parameters of the models by means of discriminative classifiers, the dialogs of patients were successfully distinguished from those of control participants. We conclude that meaning-free speech/silence sequences, reflecting inter-actant synchronization, at least partially encode typical and atypical conversational dynamics. This suggests a direct influence of theory of mind abilities onto basic speech initiative behavior.

  4. Automatic conversational scene analysis in children with Asperger syndrome/high-functioning autism and typically developing peers.

    Directory of Open Access Journals (Sweden)

    Alessandro Tavano

    Full Text Available Individuals with Asperger syndrome/High Functioning Autism fail to spontaneously attribute mental states to the self and others, a life-long phenotypic characteristic known as mindblindness. We hypothesized that mindblindness would affect the dynamics of conversational interaction. Using generative models, in particular Gaussian mixture models and observed influence models, conversations were coded as interacting Markov processes, operating on novel speech/silence patterns, termed Steady Conversational Periods (SCPs. SCPs assume that whenever an agent's process changes state (e.g., from silence to speech, it causes a general transition of the entire conversational process, forcing inter-actant synchronization. SCPs fed into observed influence models, which captured the conversational dynamics of children and adolescents with Asperger syndrome/High Functioning Autism, and age-matched typically developing participants. Analyzing the parameters of the models by means of discriminative classifiers, the dialogs of patients were successfully distinguished from those of control participants. We conclude that meaning-free speech/silence sequences, reflecting inter-actant synchronization, at least partially encode typical and atypical conversational dynamics. This suggests a direct influence of theory of mind abilities onto basic speech initiative behavior.

  5. Quantum data locking for high-rate private communication

    OpenAIRE

    Lupo, Cosmo; Lloyd, Seth

    2015-01-01

    We show that, if the accessible information is used as a security quantifier, quantum channels with a certain symmetry can convey private messages at a tremendously high rate, as high as less than one bit below the rate of non-private classical communication. This result is obtained by exploiting the quantum data locking effect. The price to pay to achieve such a high private communication rate is that accessible information security is in general not composable. However, composable security ...

  6. High-Rate Strong-Signal Quantum Cryptography

    Science.gov (United States)

    Yuen, Horace P.

    1996-01-01

    Several quantum cryptosystems utilizing different kinds of nonclassical lights, which can accommodate high intensity fields and high data rate, are described. However, they are all sensitive to loss and both the high rate and the strong-signal character rapidly disappear. A squeezed light homodyne detection scheme is proposed which, with present-day technology, leads to more than two orders of magnitude data rate improvement over other current experimental systems for moderate loss.

  7. A novel on-chip high to low voltage power conversion circuit

    International Nuclear Information System (INIS)

    Wang Hui; Wang Songlin; Mou Zaixin; Guo Baolong; Lai Xinquan; Ye Qiang; Li Xianrui

    2009-01-01

    A novel power supply transform technique for high voltage IC based on the TSMC 0.6 μm BCD process is achieved. An adjustable bandgap voltage reference is presented which is different from the traditional power supply transform technique. It can be used as an internal power supply for high voltage IC by using the push-pull output stage to enhance its load capability. High-order temperature compensated circuit is designed to ensure the precision of the reference. Only 0.01 mm 2 area is occupied using this novel power supply technique. Compared with traditional technique, 50% of the area is saved, 40% quiescent power loss is decreased, and the temperature coefficient of the reference is only 4.48 ppm/deg. C. Compared with the traditional LDO (low dropout) regulator, this power conversion architecture does not need external output capacitance and decreases the chip-pin and external components, so the PCB area and design cost are also decreased. The testing results show that this circuit works well.

  8. A novel on-chip high to low voltage power conversion circuit

    Energy Technology Data Exchange (ETDEWEB)

    Wang Hui; Wang Songlin; Mou Zaixin; Guo Baolong [Institute of Mechano-electronic Engineering, Xidian University, Xi' an 71007 (China); Lai Xinquan; Ye Qiang; Li Xianrui, E-mail: whui94@126.co [Institute of Electronic CAD, Xidian University, Xi' an 710071 (China)

    2009-03-15

    A novel power supply transform technique for high voltage IC based on the TSMC 0.6 mum BCD process is achieved. An adjustable bandgap voltage reference is presented which is different from the traditional power supply transform technique. It can be used as an internal power supply for high voltage IC by using the push-pull output stage to enhance its load capability. High-order temperature compensated circuit is designed to ensure the precision of the reference. Only 0.01 mm{sup 2} area is occupied using this novel power supply technique. Compared with traditional technique, 50% of the area is saved, 40% quiescent power loss is decreased, and the temperature coefficient of the reference is only 4.48 ppm/deg. C. Compared with the traditional LDO (low dropout) regulator, this power conversion architecture does not need external output capacitance and decreases the chip-pin and external components, so the PCB area and design cost are also decreased. The testing results show that this circuit works well.

  9. THE INFLUENCE OF CONVERSION MODEL CHOICE FOR EROSION RATE ESTIMATION AND THE SENSITIVITY OF THE RESULTS TO CHANGES IN THE MODEL PARAMETER

    Directory of Open Access Journals (Sweden)

    Nita Suhartini

    2010-06-01

    Full Text Available A study of soil erosion rates had been done on a slightly and long slope of cultivated area in Ciawi - Bogor, using 137Cs technique. The objective of the present study was to evaluate the applicability of the 137Cs technique in obtaining spatially distributed information of soil redistribution at small catchment. This paper reports the result of the choice of conversion model for erosion rate estimates and the sensitive of the changes in the model parameter. For this purpose, small site was selected, namely landuse I (LU-I. The top of a slope was chosen as a reference site. The erosion/deposit rate of individual sampling points was estimated using the conversion models, namely Proportional Model (PM, Mass Balance Model 1 (MBM1 and Mass Balance Model 2 (MBM2. A comparison of the conversion models showed that the lowest value is obtained by the PM. The MBM1 gave values closer to MBM2, but MBM2 gave a reliable values. In this study, a sensitivity analysis suggest that the conversion models are sensitive to changes in parameters that depend on the site conditions, but insensitive to changes in  parameters that interact to the onset of 137Cs fallout input.   Keywords: soil erosion, environmental radioisotope, cesium

  10. The design study of an ultra-high power EB/X-ray conversion facility

    Energy Technology Data Exchange (ETDEWEB)

    He, Zi-Feng, E-mail: hezifeng@sinap.ac.cn; Li, Deming; Huang, Jian-Ming; Yang, Yong-Jin; Zhu, Xi-Kai; Zhang, Yu-Tian

    2014-10-15

    Highlights: • We describe a 100 kW electron beam to X-rays conversion system. • We give an idea to improve the conversion efficiency and lifetime of the target. • We describe the design and thermal characteristics of the X-ray converter. - Abstract: X-ray conversion is a frequent need for irradiating the products that cannot be processed by electron beams, duo to their limited penetration capacity in materials, in radiation sterilization of disposable healthcare products and food irradiation. In this paper, we report the design of a conversion facility with a 5-MeV/120-kW electron accelerator, regarding the considerations on selection of the target materials and target structure, design of the electron beam transport line and approaches to improve the conversion efficiency and lifetime.

  11. Total skin high-dose-rate electron therapy dosimetry using TG-51

    International Nuclear Information System (INIS)

    Gossman, Michael S.; Sharma, Subhash C.

    2004-01-01

    An approach to dosimetry for total skin electron therapy (TSET) is discussed using the currently accepted TG-51 high-energy calibration protocol. The methodology incorporates water phantom data for absolute calibration and plastic phantom data for efficient reference dosimetry. The scheme is simplified to include the high-dose-rate mode conversion and provides support for its use, as it becomes more available on newer linear accelerators. Using a 6-field, modified Stanford technique, one may follow the process for accurate determination of absorbed dose

  12. High rate flame synthesis of highly crystalline iron oxide nanorods

    International Nuclear Information System (INIS)

    Merchan-Merchan, W; Taylor, A M; Saveliev, A V

    2008-01-01

    Single-step flame synthesis of iron oxide nanorods is performed using iron probes inserted into an opposed-flow methane oxy-flame. The high temperature reacting environment of the flame tends to convert elemental iron into a high density layer of iron oxide nanorods. The diameters of the iron oxide nanorods vary from 10 to 100 nm with a typical length of a few microns. The structural characterization performed shows that nanorods possess a highly ordered crystalline structure with parameters corresponding to cubic magnetite (Fe 3 O 4 ) with the [100] direction oriented along the nanorod axis. Structural variations of straight nanorods such as bends, and T-branched and Y-branched shapes are frequently observed within the nanomaterials formed, opening pathways for synthesis of multidimensional, interconnected networks

  13. A high conversion-gain Q-band InP DHBT subharmonic mixer using LO frequency doubler

    DEFF Research Database (Denmark)

    Johansen, Tom Keinicke; Vidkjær, Jens; Krozer, Viktor

    2008-01-01

    The paper presents analysis and design of a Q-band subharmonic mixer (SHM) with high conversion gain. The SHM consists of a local oscillator (LO) frequency doubler, RF pre-amplifier, and single-ended mixer. The SHM has been fabricated in a high-speed InP double heterojunction bipolar transistor (...

  14. Conversion of low BMEP 4-cylinder to high BMEP 2-cylinder large bore natural gas engine

    Science.gov (United States)

    Ladd, John

    There are more than 6,000 integral compressor engines in use on US natural gas pipelines, operating 24 hours a day, 365 days a year. Many of these engines have operated continuously for more than 50 years, with little to no modifications. Due to recent emission regulations at the local, state and federal levels much of the aging infrastructure requires retrofit technology to remain within compliance. The Engines and Energy Conversion Laboratory was founded to test these retrofit technologies on its large bore engine testbed (LBET). The LBET is a low brake mean effective pressure (BMEP) Cooper Bessemer GMVTF-4. Newer GMV models, constructed in 1980's, utilize turbocharging to increase the output power, achieving BMEP's nearly double that of the LBET. To expand the lab's testing capability and to reduce the LBET's running cost: material testing, in-depth modeling, and on engine testing was completed to evaluate the feasibility of uprating the LBET to a high BMEP two cylinder engine. Due to the LBET's age, the crankcase material properties were not known. Material samples were removed from engine to conduct an in-depth material analysis. It was found that the crankcase was cast out of a specific grade of gray iron, class 25 meehanite. A complete three dimensional model of the LBET's crankcase and power cylinders was created. Using historical engine data, the force inputs were created for a finite element analysis model of the LBET, to determine the regions of high stress. The areas of high stress were instrumented with strain gauges to iterate and validate the model's findings. Several test cases were run at the high and intermediate BMEP engine conditions. The model found, at high BMEP conditions the LBET would operate at the fatigue limit of the class 25 meehanite, operating with no factor of safety but the intermediate case were deemed acceptable.

  15. Pulse shaping for all-optical signal processing of ultra-high bit rate serial data signals

    DEFF Research Database (Denmark)

    Palushani, Evarist

    The following thesis concerns pulse shaping and optical waveform manipulation for all-optical signal processing of ultra-high bit rate serial data signals, including generation of optical pulses in the femtosecond regime, serial-to-parallel conversion and terabaud coherent optical time division...

  16. The effect of wind shielding and pen position on the average daily weight gain and feed conversion rate of grower/finisher pigs

    DEFF Research Database (Denmark)

    Jensen, Dan B.; Toft, Nils; Cornou, Cécile

    2014-01-01

    of the effects of wind shielding, linear mixed models were fitted to describe the average daily weight gain and feed conversion rate of 1271 groups (14 individuals per group) of purebred Duroc, Yorkshire and Danish Landrace boars, as a function of shielding (yes/no), insert season (winter, spring, summer, autumn...... groups placed in the 1st and 4th pen (p=0.0001). A similar effect was not seen on smaller pigs. Pen placement appears to have no effect on feed conversion rate.No interaction effects between shielding and distance to the corridor could be demonstrated. Furthermore, in models including both factors......). The effect could not be tested for Yorkshire and Danish Landrace due to lack of data on these breeds. For groups of pigs above the average start weight, a clear tendency of higher growth rates at greater distances from the central corridor was observed, with the most significant differences being between...

  17. Ultrathin and Ion-Selective Janus Membranes for High-Performance Osmotic Energy Conversion.

    Science.gov (United States)

    Zhang, Zhen; Sui, Xin; Li, Pei; Xie, Ganhua; Kong, Xiang-Yu; Xiao, Kai; Gao, Longcheng; Wen, Liping; Jiang, Lei

    2017-07-05

    The osmotic energy existing in fluids is recognized as a promising "blue" energy source that can help solve the global issues of energy shortage and environmental pollution. Recently, nanofluidic channels have shown great potential for capturing this worldwide energy because of their novel transport properties contributed by nanoconfinement. However, with respect to membrane-scale porous systems, high resistance and undesirable ion selectivity remain bottlenecks, impeding their applications. The development of thinner, low-resistance membranes, meanwhile promoting their ion selectivity, is a necessity. Here, we engineered ultrathin and ion-selective Janus membranes prepared via the phase separation of two block copolymers, which enable osmotic energy conversion with power densities of approximately 2.04 W/m 2 by mixing natural seawater and river water. Both experiments and continuum simulation help us to understand the mechanism for how membrane thickness and channel structure dominate the ion transport process and overall device performance, which can serve as a general guiding principle for the future design of nanochannel membranes for high-energy concentration cells.

  18. Feasible conversion of solid waste bauxite tailings into highly crystalline 4A zeolite with valuable application.

    Science.gov (United States)

    Ma, Dongyang; Wang, Zhendong; Guo, Min; Zhang, Mei; Liu, Jingbo

    2014-11-01

    Bauxite tailings are a major type of solid wastes generated in the flotation process. The waste by-products caused significant environmental impact. To lessen this hazardous effect from poisonous mine tailings, a feasible and cost-effective solution was conceived and implemented. Our approach focused on reutilization of the bauxite tailings by converting it to 4A zeolite for reuse in diverse applications. Three steps were involved in the bauxite conversion: wet-chemistry, alkali fusion, and crystallization to remove impurities and to prepare porous 4A zeolite. It was found that the cubic 4A zeolite was single phase, in high purity, with high crystallinity and well-defined structure. Importantly, the 4A zeolite displayed maximum calcium ion exchange capacity averaged at 296 mg CaCO3/g, comparable to commercially-available zeolite (310 mg CaCO3/g) exchange capacity. Base on the optimal synthesis condition, the reaction yield of zeolite 4A from bauxite tailings achieved to about 38.43%, hence, this study will provide a new paradigm for remediation of bauxite tailings, further mitigating the environmental and health care concerns, particularly in the mainland of PR China. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Conversion of the RB reactor neutrons by highly enriched uranium fuel and lithium deuteride

    International Nuclear Information System (INIS)

    Strugar, P.; Sotic, O.; Ninkovic, M.; Pesic, M.; Altiparmakov, D.

    1981-01-01

    A thermal-to-fast-neutron converter has been constructed at the RB reactor. The material used for the conversion of thermal neutrons is highly enriched uranium fuel of Soviet production applied in Yugoslav heavy water experimental reactors RA and RB. Calculations and preliminary measurements show that the spectrum of converted neutrons only slightly differs from that of fission neutrons. The basic characteristics of converted neutrons can be expressed by the neutron radiation dose of 800 rad (8 Gy) for 1 h of reactor operation at a power level of 1 kW. This dose is approximately 10 times higher than the neutron dose at the same place without converter. At the same time, thermal neutron and gamma radiation doses are negligible. The constructed neutron converter offers wide possibilities for applications in reactor and nuclear physics and similar disciplines, where neutron spectra of high energies are required, as well as in the domain of neutron dosimetry and biological irradiations in homogeneous fields of larger dimensions. The possibility of converting thermal reactor neutrons with energies of about 14 MeV with the aid of lithium deuteride from natural lithium has been considered too. (author)

  20. The effect of hydroxyapatite presence on the degree of conversion and polymerization rate in a model self-etching adhesive

    Science.gov (United States)

    Zhang, Ying; Wang, Yong

    2011-01-01

    Objective The effect of hydroxyapatite (HAp) content on photopolymerization of a model self-etching adhesive was studied by using attenuated total reflectance Fourier transform infrared (ATR/FT-IR) spectroscopy. Materials and methods The model adhesive contained two monomers: bis[2-(methacryloyloxy)ethyl] phosphate (2MP) and 2-hydroxyethyl methacrylate (HEMA) using a 1:1 mass ratio, representing an acidic formulation. Camphorquinone and ethyl 4-dimethylaminobenzoate were added to enable visible light photopolymerization in a constant concentration of 0.022 mmol per gram monomer. HAp [Ca10(OH)2(PO4)6] powder were added to the test solutions to obtain mass fraction of 0, 1, 2, 3, 4 wt%. The degree of conversion (DC) and the polymerization rate (PR) with/without HAp were determined using ATR/FT-IR with a time-based spectrum analysis. Results Monomer DC and PR were significantly enhanced by addition of HAp. Incorporation of 4 wt% of HAp increased DC from 20.8 (±0.3) % to 93.4 (±1.1) %, and PR from 0.42 (±0.01) %/s to 3.21 (±0.07) %/s. The pH of adhesive solutions was measured and correlated with DC and PR. The pH of test solutions was also controlled using a base (sodium hydroxide, NaOH) to similar values as when using HAp. Results indicated that both the DC and PR increased with increasing pH, regardless of additive, confirming the role of pH on polymerization. From the IR spectral comparison, changes in molecular structures of the self-etching adhesive after the addition of HAp were observed, which were correlated with the specific interaction between 2MP and HAp. The effect of viscosity was also proposed to be another possible reason for the improved polymerization. Significance The photopolymerization of a self-etching adhesive was enhanced / accelerated in the presence of HAp. The results provide the critical information for understanding the interactions/bonding between self-etching adhesives and tooth substrates. PMID:22032933

  1. In operando spectroscopic studies of high temperature electrocatalysts used for energy conversion

    Science.gov (United States)

    McIntyre, Melissa Dawn

    Solid-state electrochemical cells are efficient energy conversion devices that can be used for clean energy production or for removing air pollutants from exhaust gas emitted by combustion processes. For example, solid oxide fuel cells generate electricity with low emissions from a variety of fuel sources; solid oxide electrolysis cells produce zero-emission H2 fuel; and solid-state DeNOx cells remove NOx gases from diesel exhaust. In order to maintain high conversion efficiencies, these systems typically operate at temperatures ≥ 500°C. The high operating temperatures, however, accelerate chemical and mechanical cell degradation. To improve device durability, a mechanistic understanding of the surface chemistry occurring at the cell electrodes (anode and cathode) is critical in terms of refining cell design, material selection and operation protocols. The studies presented herein utilized in operando Raman spectroscopy coupled with electrochemical measurements to directly correlate molecular/material changes with device performance in solid oxide cells under various operating conditions. Because excessive carbon accumulation with carbon-based fuels destroys anodes, the first three studies investigated strategies for mitigating carbon accumulation on Ni cermet anodes. Results from the first two studies showed that low amounts of solid carbon stabilized the electrical output and improved performance of solid oxide fuel cells operating with syn-gas (H 2/CO fuel mixture). The third study revealed that infiltrating anodes with Sn or BaO suppressed carbon accumulation with CH4 fuel and that H2O was the most effective reforming agent facilitating carbon removal. The last two studies explored how secondary phases formed in traditional solid oxide cell materials doped with metal oxides improve electrochemical performance. Results from the fourth study suggest that the mixed ion-electron conducting Zr5Ti7O24 secondary phase can expand the electrochemically active region

  2. HIGH-RATE DISINFECTION TECHNIQUES FOR COMBIND SEWER OVERFLOW

    Science.gov (United States)

    This paper presents high-rate disinfection technologies for combined sewer overflow (CSO). The high-rate disinfection technologies of interest are: chlorination/dechlorination, ultraviolet light irradiation (UV), chlorine dioxide (ClO2 ), ozone (O3), peracetic acid (CH3COOOH )...

  3. High Graduate Unemployment Rate and Taiwanese Undergraduate Education

    Science.gov (United States)

    Wu, Chih-Chun

    2011-01-01

    An expansion in higher education in combination with the recent global economic recession has resulted in a high college graduate unemployment rate in Taiwan. This study investigates how the high unemployment rate and financial constraints caused by economic cutbacks have shaped undergraduates' class choices, job needs, and future income…

  4. Circuit and interconnect design for high bit-rate applications

    NARCIS (Netherlands)

    Veenstra, H.

    2006-01-01

    This thesis presents circuit and interconnect design techniques and design flows that address the most difficult and ill-defined aspects of the design of ICs for high bit-rate applications. Bottlenecks in interconnect design, circuit design and on-chip signal distribution for high bit-rate

  5. Feasible conversion of solid waste bauxite tailings into highly crystalline 4A zeolite with valuable application

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Dongyang; Wang, Zhendong; Guo, Min [State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083 (China); Zhang, Mei, E-mail: zhangmei@ustb.edu.cn [State Key Laboratory of Advanced Metallurgy, University of Science and Technology Beijing, Beijing 100083 (China); Liu, Jingbo [The Department of Chemistry, Texas A and M University-Kingsville, Kingsville, TX 78363 (United States); The Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2014-11-15

    Highlights: • Concept to convert waste to valuable product is carried out in this study. • An industrially feasible and cost-effective approach was developed and optimized. • Highly crystalline and well-defined zeolite was produced under moderate conditions. • The zeolite derived from the bauxite tailings displayed high ion exchange capacity. • Bauxite tailings have potential application in heavy metal ions adsorbent. - Abstract: Bauxite tailings are a major type of solid wastes generated in the flotation process. The waste by-products caused significant environmental impact. To lessen this hazardous effect from poisonous mine tailings, a feasible and cost-effective solution was conceived and implemented. Our approach focused on reutilization of the bauxite tailings by converting it to 4A zeolite for reuse in diverse applications. Three steps were involved in the bauxite conversion: wet-chemistry, alkali fusion, and crystallization to remove impurities and to prepare porous 4A zeolite. It was found that the cubic 4A zeolite was single phase, in high purity, with high crystallinity and well-defined structure. Importantly, the 4A zeolite displayed maximum calcium ion exchange capacity averaged at 296 mg CaCO{sub 3}/g, comparable to commercially-available zeolite (310 mg CaCO{sub 3}/g) exchange capacity. Base on the optimal synthesis condition, the reaction yield of zeolite 4A from bauxite tailings achieved to about 38.43%, hence, this study will provide a new paradigm for remediation of bauxite tailings, further mitigating the environmental and health care concerns, particularly in the mainland of PR China.

  6. Feasible conversion of solid waste bauxite tailings into highly crystalline 4A zeolite with valuable application

    International Nuclear Information System (INIS)

    Ma, Dongyang; Wang, Zhendong; Guo, Min; Zhang, Mei; Liu, Jingbo

    2014-01-01

    Highlights: • Concept to convert waste to valuable product is carried out in this study. • An industrially feasible and cost-effective approach was developed and optimized. • Highly crystalline and well-defined zeolite was produced under moderate conditions. • The zeolite derived from the bauxite tailings displayed high ion exchange capacity. • Bauxite tailings have potential application in heavy metal ions adsorbent. - Abstract: Bauxite tailings are a major type of solid wastes generated in the flotation process. The waste by-products caused significant environmental impact. To lessen this hazardous effect from poisonous mine tailings, a feasible and cost-effective solution was conceived and implemented. Our approach focused on reutilization of the bauxite tailings by converting it to 4A zeolite for reuse in diverse applications. Three steps were involved in the bauxite conversion: wet-chemistry, alkali fusion, and crystallization to remove impurities and to prepare porous 4A zeolite. It was found that the cubic 4A zeolite was single phase, in high purity, with high crystallinity and well-defined structure. Importantly, the 4A zeolite displayed maximum calcium ion exchange capacity averaged at 296 mg CaCO 3 /g, comparable to commercially-available zeolite (310 mg CaCO 3 /g) exchange capacity. Base on the optimal synthesis condition, the reaction yield of zeolite 4A from bauxite tailings achieved to about 38.43%, hence, this study will provide a new paradigm for remediation of bauxite tailings, further mitigating the environmental and health care concerns, particularly in the mainland of PR China

  7. Phosphate conversion coating reduces the degradation rate and suppresses side effects of metallic magnesium implants in an animal model.

    Science.gov (United States)

    Rahim, Muhammad Imran; Tavares, Ana; Evertz, Florian; Kieke, Marc; Seitz, Jan-Marten; Eifler, Rainer; Weizbauer, Andreas; Willbold, Elmar; Jürgen Maier, Hans; Glasmacher, Birgit; Behrens, Peter; Hauser, Hansjörg; Mueller, Peter P

    2017-08-01

    Magnesium alloys have promising mechanical and biological properties for the development of degradable implants. However, rapid implant corrosion and gas accumulations in tissue impede clinical applications. With time, the implant degradation rate is reduced by a highly biocompatible, phosphate-containing corrosion layer. To circumvent initial side effects after implantation it was attempted to develop a simple in vitro procedure to generate a similarly protective phosphate corrosion layer. To this end magnesium samples were pre-incubated in phosphate solutions. The resulting coating was well adherent during routine handling procedures. It completely suppressed the initial burst of corrosion and it reduced the average in vitro magnesium degradation rate over 56 days almost two-fold. In a small animal model phosphate coatings on magnesium implants were highly biocompatible and abrogated the appearance of gas cavities in the tissue. After implantation, the phosphate coating was replaced by a layer with an elemental composition that was highly similar to the corrosion layer that had formed on plain magnesium implants. The data demonstrate that a simple pre-treatment could improve clinically relevant properties of magnesium-based implants. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 1622-1635, 2017. © 2016 Wiley Periodicals, Inc.

  8. Absorbed-dose beam quality conversion factors for cylindrical chambers in high energy photon beams.

    Science.gov (United States)

    Seuntjens, J P; Ross, C K; Shortt, K R; Rogers, D W

    2000-12-01

    Recent working groups of the AAPM [Almond et al., Med. Phys. 26, 1847 (1999)] and the IAEA (Andreo et al., Draft V.7 of "An International Code of Practice for Dosimetry based on Standards of Absorbed Dose to Water," IAEA, 2000) have described guidelines to base reference dosimetry of high energy photon beams on absorbed dose to water standards. In these protocols use is made of the absorbed-dose beam quality conversion factor, kQ which scales an absorbed-dose calibration factor at the reference quality 60Co to a quality Q, and which is calculated based on state-of-the-art ion chamber theory and data. In this paper we present the measurement and analysis of beam quality conversion factors kQ for cylindrical chambers in high-energy photon beams. At least three chambers of six different types were calibrated against the Canadian primary standard for absorbed dose based on a sealed water calorimeter at 60Co [TPR10(20)=0.572, %dd(10)x=58.4], 10 MV [TPR10(20)=0.682, %dd(10)x=69.6), 20 MV (TPR10(20)=0.758, %dd(10)x= 80.5] and 30 MV [TPR10(20) = 0.794, %dd(10)x= 88.4]. The uncertainty on the calorimetric determination of kQ for a single chamber is typically 0.36% and the overall 1sigma uncertainty on a set of chambers of the same type is typically 0.45%. The maximum deviation between a measured kQ and the TG-51 protocol value is 0.8%. The overall rms deviation between measurement and the TG-51 values, based on 20 chambers at the three energies, is 0.41%. When the effect of a 1 mm PMMA waterproofing sleeve is taken into account in the calculations, the maximum deviation is 1.1% and the overall rms deviation between measurement and calculation 0.48%. When the beam is specified using TPR10(20), and measurements are compared with kQ values calculated using the version of TG-21 with corrected formalism and data, differences are up to 1.6% when no sleeve corrections are taken into account. For the NE2571 and the NE2611A chamber types, for which the most literature data are

  9. Introduction to State Estimation of High-Rate System Dynamics.

    Science.gov (United States)

    Hong, Jonathan; Laflamme, Simon; Dodson, Jacob; Joyce, Bryan

    2018-01-13

    Engineering systems experiencing high-rate dynamic events, including airbags, debris detection, and active blast protection systems, could benefit from real-time observability for enhanced performance. However, the task of high-rate state estimation is challenging, in particular for real-time applications where the rate of the observer's convergence needs to be in the microsecond range. This paper identifies the challenges of state estimation of high-rate systems and discusses the fundamental characteristics of high-rate systems. A survey of applications and methods for estimators that have the potential to produce accurate estimations for a complex system experiencing highly dynamic events is presented. It is argued that adaptive observers are important to this research. In particular, adaptive data-driven observers are advantageous due to their adaptability and lack of dependence on the system model.

  10. Processing of high-temperature superconductors at high strain rates

    International Nuclear Information System (INIS)

    Mamalis, A.G.; Pantazsopoulos, G.; Manolakos, D.E.; Szalay, A.

    2000-01-01

    This new book provides, for the first time, a systematic, unified presentation of all steps in the processing of high-temperature superconductor materials, ranging from synthesis of various systems to fabrication and industrial applications. Also covered are characterization techniques and current directions in research and development. The authors are leading specialists who bring to this new book their many years of experience in research, education and industrial engineering work in superconductor materials. This book is primarily focused on the bulk-fabrication techniques of high-temperature ceramic superconducting components, especially on the combination of dynamic powder-consolidation and subsequent deformation processing. The properties of these ceramics, which are difficult-to-form materials by applying conventional techniques, are combined for the net-shape manufacturing of such components for the construction of HTS deviceshor e llipsis. However, very important topics such as superconducting structures, chemical synthesis, film fabrication and characterization techniques are also reviewedhor e llipsis to provide a complete, comprehensive view of superconductors engineering

  11. High dose rate brachytherapy in treatment of high grade astrocytomas

    International Nuclear Information System (INIS)

    Garcia-Alejo, R.; Delgado, J.M.; Cerro, E. del; Torres, J.J.; Martinez, R.

    1996-01-01

    From May 1994 to June 1995, 18 patients with high grade astrocytomas were entered prospectively on a selective protocol combining surgery, external beam radiotherapy, stereotactic interstitial implantation with HDR Iridium 192 and chemotherapy. Only those patients with tumor size 100cc or less average dimension, high grade astrocytoma, Karnofsky 70 or greater, unilateral, circumscribed, unifocal, tumor stable or responding to external radiation and supratentorial were included in the study. Ages ranged from 16 to 69 years. There were 13 males and 5 females. Surgery consisted of biopsy only in 3 patients, subtotal resection in 11, and gross total resection in 4 patients. Focal external beam radiation portals included the contrast enhancing mass on CT scan plus a 3 cm margin. The protocol called for minimum tumor dose of 60 Gy to be given in 2 Gy daily fractions. An interstitial brachytherapy boost was to be performed two weeks after the conclusion of external beam radiation. The dose was 30 Gy in 4 fractions. The authors analyze on basis on their personal experience, the possibilities and the limits offered by this therapeutic procedure in neuro-oncology. Using stereotactic techniques, interstitial brachytherapy of brain tumors was technically possible with negligible acute morbidity and mortality, and appeared to be effective and may provide for an increase in tumor control in selected cases

  12. Wavelength conversion of a 40 Gb/s RZ-DPSK signal using four-wave mixing in a dispersion-flattened highly nonlinear photonic crystal fiber

    DEFF Research Database (Denmark)

    Andersen, Peter Andreas; Tokle, Torger; Geng, Yan

    2005-01-01

    Wavelength conversion of a 40-Gb/s return-to-zero differential phase-shift keying signal is demonstrated in a highly nonlinear photonic crystal fiber (HNL-PCF) for the first time. A conversion efficiency of -20 dB for a pump power of 23 dBm and a conversion bandwidth of 31 nm, essentially limited...

  13. A Low-Cost Time-Hopping Impulse Radio System for High Data Rate Transmission

    Directory of Open Access Journals (Sweden)

    Jinyun Zhang

    2005-03-01

    Full Text Available We present an efficient, low-cost implementation of time-hopping impulse radio that fulfills the spectral mask mandated by the FCC and is suitable for high-data-rate, short-range communications. Key features are (i all-baseband implementation that obviates the need for passband components, (ii symbol-rate (not chip rate sampling, A/D conversion, and digital signal processing, (iii fast acquisition due to novel search algorithms, and (iv spectral shaping that can be adapted to accommodate different spectrum regulations and interference environments. Computer simulations show that this system can provide 110 Mbps at 7–10 m distance, as well as higher data rates at shorter distances under FCC emissions limits. Due to the spreading concept of time-hopping impulse radio, the system can sustain multiple simultaneous users, and can suppress narrowband interference effectively.

  14. Pictorial Conversations.

    Science.gov (United States)

    Hooper, Kristina

    1982-01-01

    Provides the rationale for considering communication in a graphic domain and suggests a specific goal for designing work stations which provide graphic capabilities in educational settings. The central element of this recommendation is the "pictorial conversation", a highly interactive exchange that includes pictures as the central elements.…

  15. Towards the reanalysis of void coefficients measurements at proteus for high conversion light water reactor lattices

    Energy Technology Data Exchange (ETDEWEB)

    Hursin, M.; Koeberl, O.; Perret, G. [Paul Scherrer Institut PSI, 5232 Villigen (Switzerland)

    2012-07-01

    High Conversion Light Water Reactors (HCLWR) allows a better usage of fuel resources thanks to a higher breeding ratio than standard LWR. Their uses together with the current fleet of LWR constitute a fuel cycle thoroughly studied in Japan and the US today. However, one of the issues related to HCLWR is their void reactivity coefficient (VRC), which can be positive. Accurate predictions of void reactivity coefficient in HCLWR conditions and their comparisons with representative experiments are therefore required. In this paper an inter comparison of modern codes and cross-section libraries is performed for a former Benchmark on Void Reactivity Effect in PWRs conducted by the OECD/NEA. It shows an overview of the k-inf values and their associated VRC obtained for infinite lattice calculations with UO{sub 2} and highly enriched MOX fuel cells. The codes MCNPX2.5, TRIPOLI4.4 and CASMO-5 in conjunction with the libraries ENDF/B-VI.8, -VII.0, JEF-2.2 and JEFF-3.1 are used. A non-negligible spread of results for voided conditions is found for the high content MOX fuel. The spread of eigenvalues for the moderated and voided UO{sub 2} fuel are about 200 pcm and 700 pcm, respectively. The standard deviation for the VRCs for the UO{sub 2} fuel is about 0.7% while the one for the MOX fuel is about 13%. This work shows that an appropriate treatment of the unresolved resonance energy range is an important issue for the accurate determination of the void reactivity effect for HCLWR. A comparison to experimental results is needed to resolve the presented discrepancies. (authors)

  16. Type conversion by high-energy particles in Hg1-xCdxTe compounds

    International Nuclear Information System (INIS)

    Blanchard, C.; Favre, J.; Barbot, J.F.; Desoyer, J.C.; Toulemonde, M.; Konczykowski, M.; Le Scoul, D.; Dessus, J.L.

    1990-01-01

    p-type crystals of the ternary compounds Hg 1-x Cd x Te have been irradiated with high-energy ions and electrons. Electron-beam-induced current signals on xenon- and krypton-irradiated Hg 1-x Cd x Te show that n-type conversion, occurring all along the ion path, is related to the presence of mercury atoms. Resistivity and Hall measurements on carbon-, oxygen-, xenon- and electron-irradiated Hg 0.8 Cd 0.2 Te crystals allow us to determine the effective cross section for atomic displacement. We observe, for electron-irradiated samples, a saturation in carrier concentration interpreted as the pinning of the Fermi level at a resonant donor state 370 meV above the bottom of the conduction band. Comparison between ion and electron irradiations shows that electrically active produced defects are mainly due to atomic collisions. Additional reduction of defect production efficiency for xenon ions may be the onset of some energy transfer from electronic loss to target atoms

  17. High-temperature conversion of methane on a composite gadolinia-doped ceria-gold electrode

    DEFF Research Database (Denmark)

    Marina, O.A.; Mogensen, Mogens Bjerg

    1999-01-01

    Direct electrochemical oxidation of methane was attempted on a gadolinia-doped ceria Ce(0.6)Gd(0.4)O(1.8) (CG4) electrode in a solid oxide fuel cell using a porous gold-CG4 mixture as current collector Gold is relatively inert to methane in contrast to other popular SOFC anode materials such as n......Direct electrochemical oxidation of methane was attempted on a gadolinia-doped ceria Ce(0.6)Gd(0.4)O(1.8) (CG4) electrode in a solid oxide fuel cell using a porous gold-CG4 mixture as current collector Gold is relatively inert to methane in contrast to other popular SOFC anode materials...... such as nickel and platinum. CG4 was found to exhibit a low electrocatalytic activity for methane oxidation as well as no significant reforming activity implying that the addition of an electrocatalyst or cracking catalyst to the CG4 anode is required for SOFC operating on methane. The methane conversion...... observed at the open-circuit potential and low anodic overpotentials seems to be due to thermal methane cracking in the gas phase and on the alumina surfaces in the cell housing. At high anodic overpotentials, at electrode potentials where oxygen evolution was expected to take place, the formation of CO(2...

  18. Feasibility survey on international cooperation for high efficiency energy conversion technology in fiscal 1993

    Science.gov (United States)

    1994-03-01

    Following cooperative researches on fuel cell jointly conducted by NEDO and EGAT (Electricity Generating Authority of Thailand), the survey on international cooperation relating to high efficiency energy conversion technology was carried out for the ASEAN countries. The paper summed up the results of the survey. The study of the international cooperation is made for the following three items: a program for periodical exchange of information with EGAT, a project for cooperative research on phosphoric acid fuel cell in Indonesia, and a project for cooperative research with EGAT on electric power storage by advanced battery. In Malaysia, which is small in scale of state, part of the Ministry of Energy, Telecommunication and Posts is only in charge of the energy issue. Therefore, the situation is that they cannot answer well to many items of research/development cooperation brought in from Japan. The item of medium- and long-term developmental research in the Philippines is about the problems which are seen subsequently in the Manila metropolitan area where the problem of outage is being settled. Accordingly, it is essential to promote the cooperative research, well confirming policies and systems of the Ministry of Energy and the national electricity corporation.

  19. Biosyngas Fischer. Tropsch conversion by high Fe loaded supported catalysts prepared with ultrasound and microwave

    Energy Technology Data Exchange (ETDEWEB)

    Pirola, C.; Di Fronzo, A.; Boffito, D.C.; Bianchi, C. [Milano Univ. (Italy). Dipt. di Chimica; Di Michele, A. [Perugia Univ. (Italy). Dipt. di Fisica

    2012-07-01

    Catalysts with iron high loading of 30 wt%, promoted with K (2.0 wt%) and Cu (3.75 wt%), have been synthesized according to three different methods: (1) the traditional impregnation method (TR); (2) Ultrasound (US) assisted TR method; (3) Microwave (MW) assisted TR method. All the samples have been fully characterized by BET, ICP/OES, XRPD, TG-DTA, FT-IR, TPR, SEM and TEM and tested in a laboratory pilot plant for Fischer-Tropsch synthesis working at 220 C and 20 bar. The results of the catalysts characterization indicated that the morphology of the samples strongly depends on the method of preparation. The best FTS results in term of C{sub 2+} yield (41%) has been obtained using MW with a good value of the selectivity towards heavy hydrocarbons, while in term of CO conversion (58%), using US. The samples prepared with non-traditional methods show FTS better results, probably due to a more wide and uniform distribution of Fe in the medium during the synthesis phase. (orig.)

  20. Transverse Electromagnetic Mode Conversion for High-Harmonic Self-Probing Spectroscopy

    Directory of Open Access Journals (Sweden)

    Antoine Camper

    2015-02-01

    Full Text Available We report on high-order harmonic (HHG two-source interferometry (TSI in molecular gases. We used a 0-\\(\\pi\\ phase plate to create two bright spots at the focus of a lens by converting a Gaussian laser beam into a TEM please define \\(_{01}\\ Transverse Electromagnetic Mode. The two bright foci produce two synchronized HHG sources. One of them is used to probe on-going dynamics in the generating medium, while the other serves to heterodyne the signal. The interference of the emissions in the far–field gives access to the phase difference between the two sources. In self–probing HHG phase spectroscopy, one of the two sources is used as a reference while the other one probes some on goin dynamics in the generating medium. We first compute overlap integrals to investigate the mode conversion efficiency. We then establish a clear relation between the laser phase-front curvature and the far-field overlap of the two HHG beams. Both Fresnel diffraction calculations and an experimental lens position scan are used to reveal variations of the phase front inclination in each source. We show that this arrangement offers \\(\\frac{\\lambda_{XUV}}{100}\\ precision, enabling extremely sensitive phase measurements. Finally, we use this compact setup for TSI and measure phase variations across the molecular alignment revival of nitrogen and in vibrating sulfur hexafluoride. In both gases, the phase variations change sign around the ionization threshold of the investigated molecule.

  1. High-Efficiency, Nanowire Based Thermoelectric Devices for Radioisotope Power Conversion, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This SBIR Phase I proposal responds to topic S3.03 of the 2010 NASA SBIR solicitation, for Power Generation and Conversion. Thermoelectric devices offer a simple and...

  2. Design study on evaluation for power conversion system concepts in high temperature gas cooled reactor with gas turbine

    International Nuclear Information System (INIS)

    Minatsuki, Isao; Mizokami, Yorikata

    2007-01-01

    The design studies on High Temperature Gas Cooled Reactor with Gas Turbine (HTGR-GT) have been performed, which were mainly promoted by Japan Atomic Energy Agency (JAEA) and supported by fabricators in Japan. HTGR-GT plant feature is almost determined by selection of power conversion system concepts. Therefore, plant design philosophy is observed characteristically in selection of them. This paper describes the evaluation and analysis of the essential concepts of the HTGR-GT power conversion system through the investigations based on our experiences and engineering knowledge as a fabricator. As a result, the following concepts were evaluated that have advantages against other competitive one, such as the horizontal turbo machine rotor, the turbo machine in an individual vessel, the turbo machine with single shaft, the generator inside the power conversion vessel, and the power conversion system cycle with an intercooler. The results of the study can contribute as reference data when the concepts will be selected. Furthermore, we addressed reasonableness about the concept selection of the Gas Turbine High Temperature Reactor GTHTR300 power conversion system, which has been promoted by JAEA. As a conclusion, we recognized the GTHTR300 would be one of the most promising concepts for commercialization in near future. (author)

  3. Low-Enriched Uranium Fuel Conversion Activities for the High Flux Isotope Reactor, Annual Report for FY 2011

    Energy Technology Data Exchange (ETDEWEB)

    Renfro, David G [ORNL; Cook, David Howard [ORNL; Freels, James D [ORNL; Griffin, Frederick P [ORNL; Ilas, Germina [ORNL; Sease, John D [ORNL; Chandler, David [ORNL

    2012-03-01

    This report describes progress made during FY11 in ORNL activities to support converting the High Flux Isotope Reactor (HFIR) from high-enriched uranium (HEU) fuel to low-enriched uranium (LEU) fuel. Conversion from HEU to LEU will require a change in fuel form from uranium oxide to a uranium-molybdenum (UMo) alloy. With both radial and axial contouring of the fuel foil and an increase in reactor power to 100 MW, calculations indicate that the HFIR can be operated with LEU fuel with no degradation in performance to users from the current levels achieved with HEU fuel. Studies are continuing to demonstrate that the fuel thermal safety margins can be preserved following conversion. Studies are also continuing to update other aspects of the reactor steady state operation and accident response for the effects of fuel conversion. Technical input has been provided to Oregon State University in support of their hydraulic testing program. The HFIR conversion schedule was revised and provided to the GTRI program. In addition to HFIR conversion activities, technical support was provided directly to the Fuel Fabrication Capability program manager.

  4. Low-Enriched Uranium Fuel Conversion Activities for the High Flux Isotope Reactor, Annual Report for FY 2011

    International Nuclear Information System (INIS)

    Renfro, David G.; Cook, David Howard; Freels, James D.; Griffin, Frederick P.; Ilas, Germina; Sease, John D.; Chandler, David

    2012-01-01

    This report describes progress made during FY11 in ORNL activities to support converting the High Flux Isotope Reactor (HFIR) from high-enriched uranium (HEU) fuel to low-enriched uranium (LEU) fuel. Conversion from HEU to LEU will require a change in fuel form from uranium oxide to a uranium-molybdenum (UMo) alloy. With both radial and axial contouring of the fuel foil and an increase in reactor power to 100 MW, calculations indicate that the HFIR can be operated with LEU fuel with no degradation in performance to users from the current levels achieved with HEU fuel. Studies are continuing to demonstrate that the fuel thermal safety margins can be preserved following conversion. Studies are also continuing to update other aspects of the reactor steady state operation and accident response for the effects of fuel conversion. Technical input has been provided to Oregon State University in support of their hydraulic testing program. The HFIR conversion schedule was revised and provided to the GTRI program. In addition to HFIR conversion activities, technical support was provided directly to the Fuel Fabrication Capability program manager.

  5. High frame-rate neutron radiography of dynamic events

    International Nuclear Information System (INIS)

    Bossi, R.H.; Robinson, A.H.; Barton, J.P.

    1981-01-01

    A system has been developed to perform neutron radiographic analysis of dynamic events having a duration of several milliseconds. The system has been operated in the range of 2000 to 10,000 frames/second. Synchronization has provided high-speed-motion neutron radiographs for evaluation of the firing cycle of 7.62 mm munition rounds within a steel rifle barrel. The system has also been used to demonstrate the ability to produce neutron radiographic movies of two-phase flow. The equipment uses the Oregon State University TRIGA reactor capable of pulsing to 3000 MW peak power, a neutron beam collimator, a scintillator neutron conversion screen coupled to an image intensifier, and a 16 mm high speed movie camera. The peak neutron flux incident at the object position is approximately 4 x 10 11 n/cm 2 s with a pulse, full width at half maximum, of 9 ms. Special studies have been performed on the scintillator conversion screens and on the effects of statistical limitations on the image quality. Modulation transfer function analysis has been used to assist in the evaluation of the system performance

  6. High frame-rate neutron radiography of dynamic events

    International Nuclear Information System (INIS)

    Bossi, R.H.; Robinson, A.H.; Barton, J.P.

    1983-01-01

    A system has been developed to perform neutron radiographic analysis of dynamic events having a duration of several milliseconds. The system has been operated in the range of 2000 to 10,000 frames/second. Synchronization has provided high-speed-motion neutron radiographs for evaluation of the firing cycle of 7.62 mm munition rounds within a steel rifle barrel. The system has also been used to demonstrate the ability to produce neutron radiographic movies of two phase flow. The equipment uses the Oregon State University TRIGA reactor capable of pulsing to 3000 MW peak power, a neutron beam collimator, a scintillator neutron conversion screen coupled to an image intensifier, and a 16 mm high speed movie camera. The peak neutron flux incident at the object position is approximately 4 x 10 11 n/cm 2 s with a pulse, full width at half maximum, of 9 ms. Special studies have been performed on the scintillator conversion screens and on the effects of statistical limitations on the image quality. Modulation transfer function analysis has been used to assist in the evaluation of the system performance. (Auth.)

  7. Status of the conversion working plan in the High Flux Reactor (Petten, The Netherlands)

    International Nuclear Information System (INIS)

    Hendriks, J.A.; Thijssen, P.J.M.; Wijtsma, F.J.; Gevers, A.; Guidez, J.

    2000-01-01

    The conversion from HEU to LEU has often many disadvantages: flux penalties, increase of fuel consumption, cost and delay to obtain a new license etc. But to fulfill the non-proliferation programme, and to simplify the future fuel supply, the HFR renewed in 1998 studies on conversion possibilities. To minimize the conversion costs, these studies were made with a progressive conversion that avoids the need of one new core and permits to begin the conversion with a replacement of 5 elements at each cycle. Hence the conversion can be made in 7 cycles, without special elements and with a normal bum-up for each element. To avoid an increase of fuel consumption, an increase of the fuel cycle length from 24.7 to 28.3 days was also considered. This point allows reducing the number of annual cycles from 1 to 10 and enables in one cycle to have the possibility of four successive irradiations for Molybdenum production (7 days) in one irradiation position. A working plan for fuel licensing has been sent to the safety authorities and is presented in the paper. (author)

  8. Rates and predictors of remission, recurrence and conversion to bipolar disorder after the first lifetime episode of depression

    DEFF Research Database (Denmark)

    Bukh, J. D.; Andersen, P. K.; Kessing, L. V.

    2016-01-01

    .6% converted to bipolar disorder (6.3% within the first 2 years). Non-remission increased with younger age, co-morbid anxiety and suicidal ideations. Recurrence increased with severity and treatment resistance of the first depression, and conversion to bipolar disorder with treatment resistance, a family......BACKGROUND: In depression, non-remission, recurrence of depressive episodes after remission and conversion to bipolar disorder are crucial determinants of poor outcome. The present study aimed to determine the cumulative incidences and clinical predictors of these long-term outcomes after the first...... lifetime episode of depression. METHOD: A total of 301 in- or out-patients aged 18-70 years with a validated diagnosis of a single depressive episode were assessed from 2005 to 2007. At 5 years of follow-up, 262 patients were reassessed by means of the life chart method and diagnostic interviews from 2011...

  9. Conversion electrons in the SDC

    International Nuclear Information System (INIS)

    Wicklund, A.B.

    1991-01-01

    We summarize a preliminary analysis of the rates for conversion electrons in the SDC detector, relative to other interesting sources of prompt electrons. We have used Papageno V3.30, and other available NLO calculations to estimate inclusive rates in the central region (η less than 2.0), and we have cross checked these using CDF data at 1.8 TeV. We have considered three sources of ''isolated'' electrons, namely inclusive W/Z production; top quark (Mt=140); and QCD prompt photon production, followed by conversion in 10% XO. This value approximates the inner silicon detector at SDC. Additional conversions will occur in the outer tracking chamber, but the trigger and track reconstruction efficiency will be lower. We have also considered ''nonisolated'' leptons coming from inclusive bottom production, photon conversions resulting from π 0 ,η production in jets, and high pt hadrons faking electrons

  10. Quantum data locking for high-rate private communication

    International Nuclear Information System (INIS)

    Lupo, Cosmo; Lloyd, Seth

    2015-01-01

    We show that, if the accessible information is used as a security quantifier, quantum channels with a certain symmetry can convey private messages at a tremendously high rate, as high as less than one bit below the rate of non-private classical communication. This result is obtained by exploiting the quantum data locking effect. The price to pay to achieve such a high private communication rate is that accessible information security is in general not composable. However, composable security holds against an eavesdropper who is forced to measure her share of the quantum system within a finite time after she gets it. (paper)

  11. Anhydrous ZnCl2: A Highly Efficient Reagent for Facile and Regioselective Conversion of Epoxides to β-Chlorohydrins

    Directory of Open Access Journals (Sweden)

    Ronak Eisavi

    2016-01-01

    Full Text Available Facile conversion of structurally different epoxides to the corresponding β-chlorohydrins was carried out successfully with anhydrous ZnCl2 in CH3CN. The reactions were carried out within 10-50 min to give β-chlorohydrins with perfect regioselectivity and high yields (80-97%.

  12. Influence of the flux axial form on the conversion rate and duration of cycle between recharging for ThPu and U{sub nat} fuels in CANDU reactors; Influence de la forme axiale du flux sur le taux de conversion et la duree du cycle entre rechargements pour du combustible ThPu et U{sub nat} dans les reacteurs CANDU

    Energy Technology Data Exchange (ETDEWEB)

    Chambon, Richard [Laboratoire de Physique Subatomique et de Cosmologie, Universite Joseph Fourier / CNRS-IN2P3, 53 Avenue des Martyrs, F-38026 Grenoble (France)

    2007-01-15

    To face the increasing world power demand the world nuclear sector must be continuously updated and developed as well. Thus reactors of new types are introduced and advanced fuel cycles are proposed. The technological and economic feasibility and the transition of the present power park to a renewed park require thorough studies and scenarios, which are highly dependent on the reactor performances. The conversion rate and cycle span between recharging are important parameters in the scenarios studies. In this frame, we have studied the utilisation of thorium in the CANDU type reactors and particularly the influence of axial form of the flux, i.e. of the recharging mode, on the conversion rate and duration of the cycle between recharging. The results show that up to a first approximation the axial form of the flux resulting from the neutron transport calculations for assessing the conversion rate is not necessary to be taken into account. However the time span between recharging differs up to several percents if the axial form of the flux is taken into consideration in transport calculations. Thus if the burnup or the recharging frequency are parameters which influence significantly the deployment scenarios of a nuclear park an approach more refined than a simple transport evolution in a typical cell/assembly is recommended. Finally, the results of this study are not more general than for the assumed conditions but they give a thorough calculation method valid for any recharging/fuel combination in a CANDU type reactor.

  13. Effectiveness of high interest rate policy on exchange rates: A reexamination of the Asian financial crisis

    Directory of Open Access Journals (Sweden)

    Chin Diew Lai

    2006-09-01

    Full Text Available One of the most controversial issues in the aftermath of the Asian financial crisis has been the appropriate response of monetary policy to a sharp decline in the value of some currencies. In this paper, we empirically examine the effects on Asian exchange rates of sharply higher interest rates during the Asian financial crisis. Taking account of the currency contagion effect, our results indicate that sharply higher interest rates helped to support the exchange rates of South Korea, the Philippines, and Thailand. For Malaysia, no significant causal relation is found from the rate of interest to exchange rates, as the authorities in Malaysia did not actively adopt a high interest rate policy to defend the currency.

  14. Noise and conversion performance of a high-Tc superconducting Josephson junction mixer at 0.6 THz

    Science.gov (United States)

    Gao, Xiang; Du, Jia; Zhang, Ting; Guo, Yingjie Jay

    2017-11-01

    This letter presents both theoretical and experimental investigations on the noise and conversion performance of a high-Tc superconducting (HTS) step-edge Josephson-junction mixer at the frequency of 0.6 THz and operating temperatures of 20-40 K. Based on the Y-factor and U-factor methods, a double-sideband noise temperature of around 1000 K and a conversion gain of -3.5 dB were experimentally obtained at 20 K. At the temperature of 40 K, the measured mixer noise and conversion efficiency are around 2100 K and -10 dB, respectively. The experimental data are in good agreement with the numerical analysis results using the three-port model. A detailed performance comparison with other reported HTS terahertz mixers has confirmed the superior performance of our presented mixer device.

  15. Conversion Between Mini-Mental State Examination, Montreal Cognitive Assessment, and Dementia Rating Scale-2 Scores in Parkinson’s Disease

    Science.gov (United States)

    van Steenoven, Inger; Aarsland, Dag; Hurtig, Howard; Chen-Plotkin, Alice; Duda, John E.; Rick, Jacqueline; Chahine, Lama M.; Dahodwala, Nabila; Trojanowski, John Q.; Roalf, David R.; Moberg, Paul J.; Weintraub, Daniel

    2015-01-01

    Cognitive impairment is one of the earliest, most common, and most disabling non-motor symptoms in Parkinson’s disease (PD). Thus, routine screening of global cognitive abilities is important for the optimal management of PD patients. Few global cognitive screening instruments have been developed for or validated in PD patients. The Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment (MoCA), and Dementia Rating Scale-2 (DRS-2) have been used extensively for cognitive screening in both clinical and research settings. Determining how to convert the scores between instruments would facilitate the longitudinal assessment of cognition in clinical settings and the comparison and synthesis of cognitive data in multicenter and longitudinal cohort studies. The primary aim of this study was to apply a simple and reliable algorithm for the conversion of MoCA to MMSE scores in PD patients. A secondary aim was to apply this algorithm for the conversion of DRS-2 to both MMSE and MoCA scores. The cognitive performance of a convenience sample of 360 patients with idiopathic PD was assessed by at least two of these cognitive screening instruments. We then developed conversion scores between the MMSE, MoCA, and DRS-2 using equipercentile equating and log-linear smoothing. The conversion score tables reported here enable direct and easy comparison of three routinely used cognitive screening assessments in PD patients. PMID:25381961

  16. How Did Successful High Schools Improve Their Graduation Rates?

    Science.gov (United States)

    Robertson, Janna Siegel; Smith, Robert W.; Rinka, Jason

    2016-01-01

    The researchers surveyed 23 North Carolina high schools that had markedly improved their graduation rates over the past five years. The administrators reported on the dropout prevention practices and programs to which they attributed their improved graduation rates. The majority of schools reported policy changes, especially with suspension. The…

  17. Effect of high heating rate on thermal decomposition behaviour of ...

    Indian Academy of Sciences (India)

    the thermal decomposition behaviour of the aforementioned powder at high heating rates was taken into considera- ... does not change the process of releasing hydrogen from titanium hydride ... from titanium hydride in a sequence of steps.

  18. Treatment of the prostate cancer with high dose rate brachytherapy

    International Nuclear Information System (INIS)

    Martinez, Alvaro; Torres Silva, Felipe

    2002-01-01

    The prostate cancer treatment in early stages is controversial. The high dose rate brachytherapy has been used like monotherapy or boost with external beam radiotherapy in advanced disease. This paper describes the technique and the advantages over other modalities

  19. Effect of high heating rate on thermal decomposition behaviour of ...

    Indian Academy of Sciences (India)

    Effect of high heating rate on thermal decomposition behaviour of titanium hydride ... hydride powder, while switching it from internal diffusion to chemical reaction. ... TiH phase and oxides form on the powder surface, controlling the process.

  20. Mechanisms of radiation - chemical conversion of high-paraffinic crude oil

    International Nuclear Information System (INIS)

    Zaikin, Yu.A.; Zaikina, R.F.; Silverman, J.

    2002-01-01

    Complete text of publication follows. Regularities of radiation-thermal cracking (RTC) are studied in high-paraffinic oil. Irradiation of oil samples by 2 MeV electrons was performed using a special facility assembled at the electron accelerator ELU-4. The following characteristic RTC features were observed in oil with high contents of heavy paraffins: low level of isomerization in light RTC fractions; very high polymerization rate and low olefin contents in RTC products; relatively low yields of light fractions at low irradiation dose rates; increase in the molecular weight of the gasoline fraction as the irradiation dose rate grows. Similar intense polymerization of RTC products was observed in our experiments with such wastes of oil extraction as asphalt-pitch-paraffin sediments (APPS). Theoretically this feedstock contains great reserves of hydrogen, and, therefore, has high potential yields of light fractions. However, in this case RTC was accompanied by intense reactions of polymerization and chemical adsorption that limited the maximum yields of light RTC products to 40% in our experiments. A specific feature of APPS radiation-induced destruction is formation of the big amount of a reactive paraffinic residue. As a result of interaction with the polymerizing residue the light liquid fractions were completely absorbed and the heavy residue got denser and solidified after several days of exposure at room temperature. RTC regularities in heavy paraffinic oil differ from those observed both in highly viscous petroleum feedstock and light paraffin oils. We attribute these observations to the behavior of heavy alkyl radicals that initiate polymerization and isomerization in heavy paraffin fractions

  1. Neutronic characteristics of FLWR in the transition phase changing from high conversion core to breeder core

    International Nuclear Information System (INIS)

    Akie, Hiroshi; Nakano, Yoshihiro; Okubo, Tsutomu

    2009-01-01

    Innovative Water Reactor for Flexible Fuel Cycle (FLWR) is a low moderation type boiling water reactor which can realize plutonium multiple recycling and breeding. For the introduction stage of FLWR, a high conversion (HC) type FLWR is proposed to keep technical continuity from current light water reactors. The HC core of FLWR has a less tight fuel lattice with lower coolant void fraction than the breeder (BR) type core. The HC type FLWR core is to be shifted to the BR core by only replacing the fuel assemblies of the same outer shape and size in the same reactor system. In the HC to BR transition phase of FLWR, there exist both types of fuel assemblies in the same core configuration. In the HC assembly, neutron spectrum is softer than in the BR assembly, and the axial fuel and blanket arrangement is different from the BR assembly. Due to these differences, there might appear a power peaking in the adjacent region between HC and BR assemblies. The power distribution in the HC + BR assemblies mixed core configuration is studied by performing assembly calculations and core calculations on a few assemblies local geometry and the whole core geometry. As a result, although a power peaking can be locally very large in the HC and BR assemblies adjacent regions, such local power peakings are shown to be effectively reduced by considering a rod-wise fuel enrichment distribution. In the whole core calculation, it seems possible to optimize the fuel assembly loading and shuffling pattern to avoid large power level mismatch between the assemblies. It is expected that FLWR can be shifted from HC type to BR type without major neutronic difficulties. (author)

  2. Increased strength of concrete subject to high loading rates

    International Nuclear Information System (INIS)

    Curbach, M.

    1987-01-01

    Within the scope of this work various problems are discussed which occur in connection with concrete under high tensile loading rates (e.g. when a plane crashes on a nuclear power plant very high loads occur which act only for a very short time). Particularly the causes for the already frequently noticed increases in strength with increasing loading rates are investigated and also the question whether this increased strength can be taken into account when dimensioning a construction. (MM) [de

  3. Quantum Communication with a High-Rate Entangled Photon Source

    Science.gov (United States)

    Wilson, Nathaniel C.; Chaffee, Dalton W.; Lekki, John D.; Wilson, Jeffrey D.

    2016-01-01

    A high generation rate photon-pair source using a dual element periodically-poled potassium titanyl phosphate (PP KTP) waveguide is described. The photon-pair source features a high pair generation rate, a compact power-efficient package, and continuous wave (CW) or pulsed operation. Characterization and test results are presented. Details and preliminary results of a laboratory free-space QKD experiment with the B92 protocol are also presented.

  4. High-accuracy resolver-to-digital conversion via phase locked loop based on PID controller

    Science.gov (United States)

    Li, Yaoling; Wu, Zhong

    2018-03-01

    The problem of resolver-to-digital conversion (RDC) is transformed into the problem of angle tracking control, and a phase locked loop (PLL) method based on PID controller is proposed in this paper. This controller comprises a typical PI controller plus an incomplete differential which can avoid the amplification of higher-frequency noise components by filtering the phase detection error with a low-pass filter. Compared with conventional ones, the proposed PLL method makes the converter a system of type III and thus the conversion accuracy can be improved. Experimental results demonstrate the effectiveness of the proposed method.

  5. Bio-energy Alliance High-Tonnage Bio-energy Crop Production and Conversion into Conventional Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Capareda, Sergio [Texas A & M Univ., College Station, TX (United States). Dept. of Biological & Agricultural Engineering; El-Halwagi, Mahmoud [Texas A & M Univ., College Station, TX (United States). Dept. of Chemical Engineering; Hall, Kenneth R. [Texas A & M Univ., College Station, TX (United States). Dept. of Chemical Engineering; Holtzapple, Mark [Texas A & M Univ., College Station, TX (United States). Dept. of Chemical Engineering; Searcy, Royce [Texas A & M Univ., College Station, TX (United States). Dept. of Biological & Agricultural Engineering; Thompson, Wayne H. [Texas A & M Univ., College Station, TX (United States). Dept. of Soil and Crop Sciences; Baltensperger, David [Texas A & M Univ., College Station, TX (United States). Dept. of Soil and Crop Sciences; Myatt, Robert [Texas A & M Univ., College Station, TX (United States). Dept. of Soil and Crop Sciences; Blumenthal, Jurg [Texas A & M Univ., College Station, TX (United States). Dept. of Soil and Crop Sciences

    2012-11-30

    Maintaining a predictable and sustainable supply of feedstock for bioenergy conversion is a major goal to facilitate the efficient transition to cellulosic biofuels. Our work provides insight into the complex interactions among agronomic, edaphic, and climatic factors that affect the sustainability of bioenergy crop yields. Our results provide science-based agronomic response measures that document how to better manage bioenergy sorghum production from planting to harvest. We show that harvest aids provide no significant benefit as a means to decrease harvest moisture or improve bioenergy yields. Our efforts to identify optimal seeding rates under varied edaphic and climatological conditions reinforce previous findings that sorghum is a resilient plant that can efficiently adapt to changing population pressures by decreasing or increasing the numbers of additional shoots or tillers – where optimal seeding rates for high biomass photoperiod sensitive sorghum is 60,000 to 70,000 seeds per acre and 100,000 to 120,000 seeds per acre for sweet varieties. Our varietal adaptability trials revealed that high biomass photoperiod sensitive energy sorghum consistently outperforms conventional photoperiod insensitive sweet sorghum and high biomass forage sorghum as the preferred bioenergy sorghum type, with combined theoretical yields of both cellulosic and fermentable water-soluble sugars producing an average yield of 1,035 gallons of EtOH per acre. Our nitrogen trials reveal that sweet sorghums produce ample amounts of water-soluble sugars with minimal increases in nitrogen inputs, and that excess nitrogen can affect minor increases in biomass yields and cellulosic sugars but decrease bioenergy quality by decreasing water-soluble sugar concentrations and increasing ash content, specifically when plant tissue nitrogen concentrations exceed 0.6 %, dry weight basis. Finally, through our growth and re-growth trials, we show that single-cut high biomass sorghum bioenergy yields

  6. High Heating Rates Affect Greatly the Inactivation Rate of Escherichia coli

    Science.gov (United States)

    Huertas, Juan-Pablo; Aznar, Arantxa; Esnoz, Arturo; Fernández, Pablo S.; Iguaz, Asunción; Periago, Paula M.; Palop, Alfredo

    2016-01-01

    Heat resistance of microorganisms can be affected by different influencing factors. Although, the effect of heating rates has been scarcely explored by the scientific community, recent researches have unraveled its important effect on the thermal resistance of different species of vegetative bacteria. Typically heating rates described in the literature ranged from 1 to 20°C/min but the impact of much higher heating rates is unclear. The aim of this research was to explore the effect of different heating rates, such as those currently achieved in the heat exchangers used in the food industry, on the heat resistance of Escherichia coli. A pilot plant tubular heat exchanger and a thermoresistometer Mastia were used for this purpose. Results showed that fast heating rates had a deep impact on the thermal resistance of E. coli. Heating rates between 20 and 50°C/min were achieved in the heat exchanger, which were much slower than those around 20°C/s achieved in the thermoresistometer. In all cases, these high heating rates led to higher inactivation than expected: in the heat exchanger, for all the experiments performed, when the observed inactivation had reached about seven log cycles, the predictions estimated about 1 log cycle of inactivation; in the thermoresistometer these differences between observed and predicted values were even more than 10 times higher, from 4.07 log cycles observed to 0.34 predicted at a flow rate of 70 mL/min and a maximum heating rate of 14.7°C/s. A quantification of the impact of the heating rates on the level of inactivation achieved was established. These results point out the important effect that the heating rate has on the thermal resistance of E. coli, with high heating rates resulting in an additional sensitization to heat and therefore an effective food safety strategy in terms of food processing. PMID:27563300

  7. Stretching of red blood cells at high strain rates

    Science.gov (United States)

    Mancuso, J. E.; Ristenpart, W. D.

    2017-10-01

    Most work on the mechanical behavior of red blood cells (RBCs) in flow has focused on simple shear flows. Relatively little work has examined RBC deformations in the physiologically important extensional flow that occurs at the entrance to a constriction. In particular, previous work suggests that RBCs rapidly stretch out and then retract upon entering the constriction, but to date no model predicts this behavior for the extremely high strain rates typically experienced there. In this Rapid Communication, we use high speed video to perform systematic measurements of the dynamic stretching behavior of RBCs as they enter a microfluidic constriction. We demonstrate that both the Kelvin-Voigt and Skalak viscoelastic models capture the observed stretching dynamics, up to strain rates as high as 2000 s-1. The results indicate that the effective elastic modulus of the RBC membrane at these strain rates is an order of magnitude larger than moduli measured by micropipette aspiration or other low strain rate techniques.

  8. Development of High Yield Feedstocks and Biomass Conversion Technology for Renewable Energy

    Energy Technology Data Exchange (ETDEWEB)

    Hashimoto, Andrew G. [Univ. of Hawaii, Honolulu, HI (United States); Crow, Susan [Univ. of Hawaii, Honolulu, HI (United States); DeBeryshe, Barbara [Univ. of Hawaii, Honolulu, HI (United States); Ha, Richard [Hamakua Springs County Farms, Hilo, HI (United States); Jakeway, Lee [Hawaiian Commercial and Sugar Company, Puunene, HI (United States); Khanal, Samir [Univ. of Hawaii, Honolulu, HI (United States); Nakahata, Mae [Hawaiian Commercial and Sugar Company, Puunene, HI (United States); Ogoshi, Richard [Univ. of Hawaii, Honolulu, HI (United States); Shimizu, Erik [Univ. of Hawaii, Honolulu, HI (United States); Stern, Ivette [Univ. of Hawaii, Honolulu, HI (United States); Turano, Brian [Univ. of Hawaii, Honolulu, HI (United States); Turn, Scott [Univ. of Hawaii, Honolulu, HI (United States); Yanagida, John [Univ. of Hawaii, Honolulu, HI (United States)

    2015-04-09

    This project had two main goals. The first goal was to evaluate several high yielding tropical perennial grasses as feedstock for biofuel production, and to characterize the feedstock for compatible biofuel production systems. The second goal was to assess the integration of renewable energy systems for Hawaii. The project focused on high-yield grasses (napiergrass, energycane, sweet sorghum, and sugarcane). Field plots were established to evaluate the effects of elevation (30, 300 and 900 meters above sea level) and irrigation (50%, 75% and 100% of sugarcane plantation practice) on energy crop yields and input. The test plots were extensive monitored including: hydrologic studies to measure crop water use and losses through seepage and evapotranspiration; changes in soil carbon stock; greenhouse gas flux (CO2, CH4, and N2O) from the soil surface; and root morphology, biomass, and turnover. Results showed significant effects of environment on crop yields. In general, crop yields decrease as the elevation increased, being more pronounced for sweet sorghum and energycane than napiergrass. Also energy crop yields were higher with increased irrigation levels, being most pronounced with energycane and less so with sweet sorghum. Daylight length greatly affected sweet sorghum growth and yields. One of the energy crops (napiergrass) was harvested at different ages (2, 4, 6, and 8 months) to assess the changes in feedstock characteristics with age and potential to generate co-products. Although there was greater potential for co-products from younger feedstock, the increased production was not sufficient to offset the additional cost of harvesting multiple times per year. The feedstocks were also characterized to assess their compatibility with biochemical and thermochemical conversion processes. The project objectives are being continued through additional support from the Office of Naval Research, and the Biomass Research and Development

  9. Solidification at the High and Low Rate Extreme

    Energy Technology Data Exchange (ETDEWEB)

    Meco, Halim [Iowa State Univ., Ames, IA (United States)

    2004-12-19

    The microstructures formed upon solidification are strongly influenced by the imposed growth rates on an alloy system. Depending on the characteristics of the solidification process, a wide range of growth rates is accessible. The prevailing solidification mechanisms, and thus the final microstructure of the alloy, are governed by these imposed growth rates. At the high rate extreme, for instance, one can have access to novel microstructures that are unattainable at low growth rates. While the low growth rates can be utilized for the study of the intrinsic growth behavior of a certain phase growing from the melt. Although the length scales associated with certain processes, such as capillarity, and the diffusion of heat and solute, are different at low and high rate extremes, the phenomena that govern the selection of a certain microstructural length scale or a growth mode are the same. Consequently, one can analyze the solidification phenomena at both high and low rates by using the same governing principles. In this study, we examined the microstructural control at both low and high extremes. For the high rate extreme, the formation of crystalline products and factors that control the microstructure during rapid solidification by free-jet melt spinning are examined in Fe-Si-B system. Particular attention was given to the behavior of the melt pool at different quench-wheel speeds. Since the solidification process takes place within the melt-pool that forms on the rotating quench-wheel, we examined the influence of melt-pool dynamics on nucleation and growth of crystalline solidification products and glass formation. High-speed imaging of the melt-pool, analysis of ribbon microstructure, and measurement of ribbon geometry and surface character all indicate upper and lower limits for melt-spinning rates for which nucleation can be avoided, and fully amorphous ribbons can be achieved. Comparison of the relevant time scales reveals that surface-controlled melt

  10. Pedalling rate affects endurance performance during high-intensity cycling

    DEFF Research Database (Denmark)

    Nielsen, Jens Steen; Hansen, Ernst Albin; Sjøgaard, Gisela

    2004-01-01

    The purpose of this study into high-intensity cycling was to: (1) test the hypothesis that endurance time is longest at a freely chosen pedalling rate (FCPR), compared to pedalling rates 25% lower (FCPR-25) and higher (FCPR+25) than FCPR, and (2) investigate how physiological variables......, and endurance time at W90 with FCPR-25, FCPR, and FCPR+25. Power reserve was calculated as the difference between applied power output at a given pedalling rate and peak crank power at this same pedalling rate. W90 was 325 (47) W. FCPR at W90 was 78 (11) rpm, resulting in FCPR-25 being 59 (8) rpm and FCPR+25...... time was negatively related to VO(2max), W90 and % MHC I, while positively related to power reserve. In conclusion, at group level, endurance time was longer at FCPR and at a pedalling rate 25% lower compared to a pedalling rate 25% higher than FCPR. Further, inter-individual physiological variables...

  11. Evaluation for reasonableness of power conversion system concepts in the gas turbine high temperature reactor (GTHTR300)

    International Nuclear Information System (INIS)

    Minatsuki, I.; Mizokami, Y.

    2007-01-01

    The conceptual design study for the Gas Turbine High Temperature Reactor (GTHTR300) was completed in 2004. In GTHTR300, SECO (Simple, Economical Competitiveness and Originality) is advocated as design philosophy in order to minimize technical and economical requirement. Furthermore the design of the GTHTR300 was developed with reflecting various view points from utilities, manufacturers and research organizations. In GTHTR300, the horizontal turbo machine rotor, the turbo machine in a separated vessel, the turbo machine with single rotor, the generator inside the power conversion vessel, and the power conversion system without inter-coolers were selected as major power conversion system concepts. This paper describes the investigation and analysis about the major concepts of GTHTR300 power conversion system in order to evaluate reasonableness of GTHTR300 design approach and acceptability with using experience and engineering knowledge of Mitsubishi Heavy Industries, Ltd., which were accumulated through the activities of HTGR-GT and HTTR (High Temperature Engineering Test Reactor) designing, manufacturing, fabricating and testing. From the result of the evaluation, it was concluded that the selection of each concept in GTHTR300 was reasonable as based on the original design philosophy SECO. As a conclusion, we expect the GTHTR300 to become one of the most promising concepts for commercialization in near future. (authors)

  12. High-power 355 nm ultraviolet lasers operating at ultrahigh repetition rate

    International Nuclear Information System (INIS)

    Chen, H; Liu, Q; Yan, P; Gong, M

    2013-01-01

    In this letter, we demonstrate a novel 355 nm ultraviolet (UV) laser operating at ultrahigh repetition rate from 300 kHz to 1 MHz. The hybrid fiber-MOPA–bulk amplifiers based IR source exhibits a high average power of 105 W with near-diffraction-limited beam quality, narrow linewidth and high polarization extinction ratio. Two-cascaded LBO crystals are employed for high efficiency frequency tripling, and a maximum 43.7 W of average UV power is achieved at 400 kHz, corresponding to a conversion efficiency as high as 41.6%. The pulse duration of the UV pulse can be tuned from 5 to 10 ns with good pulse peak stability (better than 2.2% (RMS)). (letter)

  13. Establishment of a Digital Knowledge Conversion Architecture Design Learning with High User Acceptance

    Science.gov (United States)

    Wu, Yun-Wu; Weng, Apollo; Weng, Kuo-Hua

    2017-01-01

    The purpose of this study is to design a knowledge conversion and management digital learning system for architecture design learning, helping students to share, extract, use and create their design knowledge through web-based interactive activities based on socialization, internalization, combination and externalization process in addition to…

  14. Balance of oxygen throughout the conversion of a high-level waste melter feed to glass

    Czech Academy of Sciences Publication Activity Database

    Lee, S.M.; Hrma, P.; Kloužek, Jaroslav; Pokorný, R.; Hujová, Miroslava; Dixon, D.R.; Schweiger, M. J.; Kruger, A.A.

    2017-01-01

    Roč. 43, č. 16 (2017), s. 13113-13118 ISSN 0272-8842 Institutional support: RVO:67985891 Keywords : oxygen mass balance * feed-to-glass conversion * evolved gas * oxygen partial pressure * Fe redox ratio Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass OBOR OECD: Ceramics Impact factor: 2.986, year: 2016

  15. Catalytic oxidative conversion of cellulosic biomass to formic acid and acetic acid with exceptionally high yields

    KAUST Repository

    Zhang, Jizhe; Sun, Miao; Liu, Xin; Han, Yu

    2014-01-01

    Direct conversion of raw biomass materials to fine chemicals is of great significance from both economic and ecological perspectives. In this paper, we report that a Keggin-type vanadium-substituted phosphomolybdic acid catalyst, namely H4PVMo11O40

  16. Experimental verification of high spectral entanglement for pulsed waveguided spontaneous parametric down-conversion

    DEFF Research Database (Denmark)

    Avenhaus, M.; Chekhova, M. V.; Krivitsky, Leonid

    2009-01-01

    We study the spectral properties of spontaneous parametric down-conversion (SPDC) in a periodically poled waveguided structure of potassium-titanyl-phosphate (KTP) crystal pumped by ultrashort pulses. Our theoretical analysis reveals a strongly entangled and asymmetric structure of the two...

  17. Highly efficient power system based on direct fission fragment energy conversion utilizing magnetic collimation

    International Nuclear Information System (INIS)

    Tsvetkov, Pavel V.; Hart, Ron R.; Parish, Theodore A.

    2003-01-01

    The present study was focused on developing a technologically feasible power system that is based on direct fission fragment energy conversion utilizing magnetic collimation. The new concept is an attempt to combine several advantageous design solutions, which have been proposed for application in both fission and fusion reactors, into one innovative system that can offer exceptional energy conversion efficiency. The analysis takes into consideration a wide range of operational aspects including fission fragment escape from the fuel, collimation, collection, criticality, long-term performance, energy conversion efficiency, heat removal, and safety characteristics. Specific characteristics of the individual system components and the entire system are evaluated. Consistent analysis and evaluation of the technological feasibility of the concept were achieved using state-of-the-art computer codes that allowed realistic and consistent modeling. The calculated energy conversion efficiencies for the presented designs without a thermodynamic cycle and with the heavy water cycle are 52% and 62%, respectively. The analysis indicates that efficiencies up to 90% are potentially achievable. (author)

  18. Decay rate of the false vacuum at high temperatures

    International Nuclear Information System (INIS)

    Eboli, O.J.P.; Marques, G.C.

    1986-01-01

    We investigate, within the semiclassical approach, the high temperature behaviour of the decay rate (Γ) of the metastable vacuum in Field Theory. We exhibit some exactly soluble (1+1) and (3+1) dimensional examples and develop a formal expression for γ in the high temperature limit. (Author) [pt

  19. Authoritative School Climate and High School Dropout Rates

    Science.gov (United States)

    Jia, Yuane; Konold, Timothy R.; Cornell, Dewey

    2016-01-01

    This study tested the association between school-wide measures of an authoritative school climate and high school dropout rates in a statewide sample of 315 high schools. Regression models at the school level of analysis used teacher and student measures of disciplinary structure, student support, and academic expectations to predict overall high…

  20. High-repetition-rate short-pulse gas discharge.

    Science.gov (United States)

    Tulip, J; Seguin, H; Mace, P N

    1979-09-01

    A high-average-power short-pulse gas discharge is described. This consists of a volume-preionized transverse discharge of the type used in gas lasers driven by a Blumlein energy storage circuit. The Blumlein circuit is fabricated from coaxial cable, is pulse-charged from a high-repetition-rate Marx-bank generator, and is switched by a high-repetition-rate segmented rail gap. The operation of this discharge under conditions typical of rare-gas halide lasers is described. A maximum of 900 pps was obtained, giving a power flow into the discharge of 30 kW.

  1. Authoritative school climate and high school dropout rates.

    Science.gov (United States)

    Jia, Yuane; Konold, Timothy R; Cornell, Dewey

    2016-06-01

    This study tested the association between school-wide measures of an authoritative school climate and high school dropout rates in a statewide sample of 315 high schools. Regression models at the school level of analysis used teacher and student measures of disciplinary structure, student support, and academic expectations to predict overall high school dropout rates. Analyses controlled for school demographics of school enrollment size, percentage of low-income students, percentage of minority students, and urbanicity. Consistent with authoritative school climate theory, moderation analyses found that when students perceive their teachers as supportive, high academic expectations are associated with lower dropout rates. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  2. Evolution of high tooth replacement rates in sauropod dinosaurs.

    Science.gov (United States)

    D'Emic, Michael D; Whitlock, John A; Smith, Kathlyn M; Fisher, Daniel C; Wilson, Jeffrey A

    2013-01-01

    Tooth replacement rate can be calculated in extinct animals by counting incremental lines of deposition in tooth dentin. Calculating this rate in several taxa allows for the study of the evolution of tooth replacement rate. Sauropod dinosaurs, the largest terrestrial animals that ever evolved, exhibited a diversity of tooth sizes and shapes, but little is known about their tooth replacement rates. We present tooth replacement rate, formation time, crown volume, total dentition volume, and enamel thickness for two coexisting but distantly related and morphologically disparate sauropod dinosaurs Camarasaurus and Diplodocus. Individual tooth formation time was determined by counting daily incremental lines in dentin. Tooth replacement rate is calculated as the difference between the number of days recorded in successive replacement teeth. Each tooth family in Camarasaurus has a maximum of three replacement teeth, whereas each Diplodocus tooth family has up to five. Tooth formation times are about 1.7 times longer in Camarasaurus than in Diplodocus (315 vs. 185 days). Average tooth replacement rate in Camarasaurus is about one tooth every 62 days versus about one tooth every 35 days in Diplodocus. Despite slower tooth replacement rates in Camarasaurus, the volumetric rate of Camarasaurus tooth replacement is 10 times faster than in Diplodocus because of its substantially greater tooth volumes. A novel method to estimate replacement rate was developed and applied to several other sauropodomorphs that we were not able to thin section. Differences in tooth replacement rate among sauropodomorphs likely reflect disparate feeding strategies and/or food choices, which would have facilitated the coexistence of these gigantic herbivores in one ecosystem. Early neosauropods are characterized by high tooth replacement rates (despite their large tooth size), and derived titanosaurs and diplodocoids independently evolved the highest known tooth replacement rates among archosaurs.

  3. Evolution of high tooth replacement rates in sauropod dinosaurs.

    Directory of Open Access Journals (Sweden)

    Michael D D'Emic

    Full Text Available BACKGROUND: Tooth replacement rate can be calculated in extinct animals by counting incremental lines of deposition in tooth dentin. Calculating this rate in several taxa allows for the study of the evolution of tooth replacement rate. Sauropod dinosaurs, the largest terrestrial animals that ever evolved, exhibited a diversity of tooth sizes and shapes, but little is known about their tooth replacement rates. METHODOLOGY/PRINCIPAL FINDINGS: We present tooth replacement rate, formation time, crown volume, total dentition volume, and enamel thickness for two coexisting but distantly related and morphologically disparate sauropod dinosaurs Camarasaurus and Diplodocus. Individual tooth formation time was determined by counting daily incremental lines in dentin. Tooth replacement rate is calculated as the difference between the number of days recorded in successive replacement teeth. Each tooth family in Camarasaurus has a maximum of three replacement teeth, whereas each Diplodocus tooth family has up to five. Tooth formation times are about 1.7 times longer in Camarasaurus than in Diplodocus (315 vs. 185 days. Average tooth replacement rate in Camarasaurus is about one tooth every 62 days versus about one tooth every 35 days in Diplodocus. Despite slower tooth replacement rates in Camarasaurus, the volumetric rate of Camarasaurus tooth replacement is 10 times faster than in Diplodocus because of its substantially greater tooth volumes. A novel method to estimate replacement rate was developed and applied to several other sauropodomorphs that we were not able to thin section. CONCLUSIONS/SIGNIFICANCE: Differences in tooth replacement rate among sauropodomorphs likely reflect disparate feeding strategies and/or food choices, which would have facilitated the coexistence of these gigantic herbivores in one ecosystem. Early neosauropods are characterized by high tooth replacement rates (despite their large tooth size, and derived titanosaurs and

  4. Low dose rate and high dose rate intracavitary treatment for cervical cancer

    International Nuclear Information System (INIS)

    Hareyama, Masato; Oouchi, Atsushi; Shidou, Mitsuo

    1997-01-01

    From 1984 through 1993, 144 previous untreated patients with carcinoma of uterine cervix were treated with either low dose rate 137 Cs therapy (LDR) or high dose rate 60 Co therapy (HDR). The local failure rates for more than 2-years for the primary lesions were 11.8% (8 of 63 patients) for LDR and 18.0% (11 of 61 patients). Rectal complication rates were significantly lower for HDR versus LDR (14.3% VS. 32.8%. p<0.01). Also, bladder complication rates were significantly lower for HDR versus LDR (0% VS. 10.4%, p<0.005). Treatment results in term of local control were equivalent for HDR and LDR treatment. However, the incidence of complications was higher for the LDR group than for the HDR group. (author)

  5. Application of vibrational correlation formalism to internal conversion rate: Case study of Cun (n = 3, 6, and 9) and H2/Cu3

    International Nuclear Information System (INIS)

    Chiodo, Sandro Giuseppe; Mineva, Tzonka

    2015-01-01

    This work reports non-radiative internal conversion (IC) rate constants obtained for Cu n with n = 3, 6, and 9 and H 2 on Cu 3 . The Time-Dependent Density Functional Theory (TDDFT) method was employed with three different functionals in order to investigate the electronic structures and the absorption spectra. The performance of the generalized gradient approximation of Perdew, Burke and Ernzerhof (PBE) and the hybrid B3LYP and PBE0 exchange correlation functionals in combination with the SVP and the def2-TZVP basis sets was examined. TDDFT results were used as input data to compute internal conversion rate constants. For this purpose, we have developed a program package. A description of the theoretical background used in our numerical implementation and the program input file is presented. In view of future applications of this program package in photoinduced catalysis, we present the analysis of the IC rate processes for the photodissociation of H 2 on Cu 3 . These results showed the applicability of the method and the computational program to identify the vibrational modes in transition metal clusters giving rise to the largest IC rate constant due to their interactions with the excited electronic states occurring in the hot-electron induced dissociation phenomena

  6. Measurement of viscosity of slush at high shear rates

    OpenAIRE

    小林, 俊一; 川村, 公之; 津川, 圭一; 和泉, 薫; Kobayashi, Shun'ichi; Kawamura, Kimiyuki; Tugawa, Keiichi; Izumi, Kaoru

    1988-01-01

    Measurements of viscosity of slush were carried out using a method of flow along an inclined smooth surface in a 0℃cold room. The method was used to get the values of viscosity under high shear rates (25 and 75s^). From our experiments two important results were obtained: 1) the viscosity of slush decreases with increasing shear rates; 2) The fluid behavior is pseudoplastic that the values of non-Newtonian index of viscosity were less than unity.

  7. Conversion of the University of Missouri-Rolla Reactor from high-enriched uranium to low-enriched uranium fuel

    International Nuclear Information System (INIS)

    Bolon, A.E.; Straka, M.; Freeman, D.W.

    1997-01-01

    The objectives of this project were to convert the UMR Reactor fuel from high-enriched uranium (HEU) to low-enriched uranium (LEU) fuel and to ship the HEU fuel back to the Department of Energy Savannah River Site. The actual core conversion was completed in the summer of 1992. The HEU fuel was offloaded to an onsite storage pit where it remained until July, 1996. In July, 1996, the HEU fuel was shipped to the DOE Savannah River Site. The objectives of the project have been achieved. DOE provided the following funding for the project. Several papers were published regarding the conversion project and are listed in the Attachment. In retrospect, the conversion project required much more time and effort than originally thought. Several difficulties were encountered including the unavailability of a shipping cask for several years. The authors are grateful for the generous funding provided by DOE for this project but wish to point out that much of their efforts on the conversion project went unfunded

  8. Clinical predictors of conversion to bipolar disorder in a prospective longitudinal familial high-risk sample: focus on depressive features.

    Science.gov (United States)

    Frankland, Andrew; Roberts, Gloria; Holmes-Preston, Ellen; Perich, Tania; Levy, Florence; Lenroot, Rhoshel; Hadzi-Pavlovic, Dusan; Breakspear, Michael; Mitchell, Philip B

    2017-11-07

    Identifying clinical features that predict conversion to bipolar disorder (BD) in those at high familial risk (HR) would assist in identifying a more focused population for early intervention. In total 287 participants aged 12-30 (163 HR with a first-degree relative with BD and 124 controls (CONs)) were followed annually for a median of 5 years. We used the baseline presence of DSM-IV depressive, anxiety, behavioural and substance use disorders, as well as a constellation of specific depressive symptoms (as identified by the Probabilistic Approach to Bipolar Depression) to predict the subsequent development of hypo/manic episodes. At baseline, HR participants were significantly more likely to report ⩾4 Probabilistic features (40.4%) when depressed than CONs (6.7%; p conversion' to threshold BD (hazard ratio = 6.9, p conversion were psychomotor retardation and ⩾5 MDEs. Behavioural disorders only predicted conversion to subthreshold BD (hazard ratio = 5.23, p disorders did not predict either threshold or subthreshold hypo/mania. This study suggests that specific depressive characteristics substantially increase the risk of young people at familial risk of BD going on to develop future hypo/manic episodes and may identify a more targeted HR population for the development of early intervention programs.

  9. Radiobiological aspects of continuous low dose-rate irradiation and fractionated high dose-rate irradiation

    International Nuclear Information System (INIS)

    Turesson, I.

    1990-01-01

    The biological effects of continuous low dose-rate irradiation and fractionated high dose-rate irradiation in interstitial and intracavitary radiotherapy and total body irradiation are discussed in terms of dose-rate fractionation sensitivity for various tissues. A scaling between dose-rate and fraction size was established for acute and late normal-tissue effects which can serve as a guideline for local treatment in the range of dose rates between 0.02 and 0.005 Gy/min and fraction sizes between 8.5 and 2.5 Gy. This is valid provided cell-cycle progression and proliferation can be ignored. Assuming that the acute and late tissue responses are characterized by α/β values of about 10 and 3 Gy and a mono-exponential repair half-time of about 3 h, the same total doses given with either of the two methods are approximately equivalent. The equivalence for acute and late non-hemopoietic normal tissue damage is 0.02 Gy/min and 8.5 Gy per fraction; 0.01 Gy/min and 5.5 Gy per fraction; and 0.005 Gy/min and 2.5Gy per fraction. A very low dose rate, below 0.005 Gy/min, is thus necessary to simulate high dose-rate radiotherapy with fraction sizes of about 2Gy. The scaling factor is, however, dependent on the repair half-time of the tissue. A review of published data on dose-rate effects for normal tissue response showed a significantly stronger dose-rate dependence for late than for acute effects below 0.02 Gy/min. There was no significant difference in dose-rate dependence between various acute non-hemopoietic effects or between various late effects. The consistent dose-rate dependence, which justifies the use of a general scaling factor between fraction size and dose rate, contrasts with the wide range of values for repair half-time calculated for various normal-tissue effects. This indicates that the model currently used for repair kinetics is not satisfactory. There are also few experimental data in the clinical dose-rate range, below 0.02 Gy/min. It is therefore

  10. U.S. High School Graduation Rates: Patterns and Explanations

    OpenAIRE

    Richard J. Murnane

    2013-01-01

    I survey the evidence on patterns in U.S. high school graduation rates over the period 1970–2010 and report the results of new research conducted to fill in holes in the evidence. I begin by pointing out the strengths and limitations of existing data sources. I then describe six striking patterns in graduation rates. They include stagnation over the last three decades of the twentieth century, significant race-, income-, and gender-based gaps, and significant increases in graduation rates o...

  11. THE AMERICAN HIGH SCHOOL GRADUATION RATE: TRENDS AND LEVELS*

    Science.gov (United States)

    Heckman, James J.; LaFontaine, Paul A.

    2009-01-01

    This paper applies a unified methodology to multiple data sets to estimate both the levels and trends in U.S. high school graduation rates. We establish that (a) the true rate is substantially lower than widely used measures; (b) it peaked in the early 1970s; (c) majority/minority differentials are substantial and have not converged for 35 years; (d) lower post-1970 rates are not solely due to increasing immigrant and minority populations; (e) our findings explain part of the slowdown in college attendance and rising college wage premiums; and (f) widening graduation differentials by gender help explain increasing male-female college attendance gaps. PMID:20625528

  12. THE AMERICAN HIGH SCHOOL GRADUATION RATE: TRENDS AND LEVELS.

    Science.gov (United States)

    Heckman, James J; Lafontaine, Paul A

    2010-05-01

    This paper applies a unified methodology to multiple data sets to estimate both the levels and trends in U.S. high school graduation rates. We establish that (a) the true rate is substantially lower than widely used measures; (b) it peaked in the early 1970s; (c) majority/minority differentials are substantial and have not converged for 35 years; (d) lower post-1970 rates are not solely due to increasing immigrant and minority populations; (e) our findings explain part of the slowdown in college attendance and rising college wage premiums; and (f) widening graduation differentials by gender help explain increasing male-female college attendance gaps.

  13. A review of reaction rates in high temperature air

    Science.gov (United States)

    Park, Chul

    1989-01-01

    The existing experimental data on the rate coefficients for the chemical reactions in nonequilibrium high temperature air are reviewed and collated, and a selected set of such values is recommended for use in hypersonic flow calculations. For the reactions of neutral species, the recommended values are chosen from the experimental data that existed mostly prior to 1970, and are slightly different from those used previously. For the reactions involving ions, the recommended rate coefficients are newly chosen from the experimental data obtained more recently. The reacting environment is assumed to lack thermal equilibrium, and the rate coefficients are expressed as a function of the controlling temperature, incorporating the recent multitemperature reaction concept.

  14. High rate tests of the LHCb RICH Upgrade system

    CERN Multimedia

    Blago, Michele Piero

    2016-01-01

    One of the biggest challenges for the upgrade of the LHCb RICH detectors from 2020 is to readout the photon detectors at the full 40 MHz rate of the LHC proton-proton collisions. A test facility has been setup at CERN with the purpose to investigate the behaviour of the Multi Anode PMTs, which have been proposed for the upgrade, and their readout electronics at high trigger rates. The MaPMTs are illuminated with a monochromatic laser that can be triggered independently of the readout electronics. A first series of tests, including threshold scans, is performed at low trigger rates (20 kHz) for both the readout and the laser with the purpose to characterise the behaviour of the system under test. Then the trigger rate is increased in two separate steps. First the MaPMTs are exposed to high illumination by triggering the pulsed laser at a high (20 MHz) repetition rate while the DAQ is readout at the same low rate as before. In this way the performance of the MaPMTs and the attached electronics can be evaluated ...

  15. Semi-solid electrodes having high rate capability

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Yet-Ming; Duduta, Mihai; Holman, Richard; Limthongkul, Pimpa; Tan, Taison

    2017-11-28

    Embodiments described herein relate generally to electrochemical cells having high rate capability, and more particularly to devices, systems and methods of producing high capacity and high rate capability batteries having relatively thick semi-solid electrodes. In some embodiments, an electrochemical cell includes an anode, a semi-solid cathode that includes a suspension of an active material and a conductive material in a liquid electrolyte, and an ion permeable membrane disposed between the anode and the cathode. The semi-solid cathode has a thickness in the range of about 250 .mu.m-2,500 .mu.m, and the electrochemical cell has an area specific capacity of at least 5 mAh/cm.sup.2 at a C-rate of C/2.

  16. Generation of plasma X-ray sources via high repetition rate femtosecond laser pulses

    Science.gov (United States)

    Baguckis, Artūras; Plukis, Artūras; Reklaitis, Jonas; Remeikis, Vidmantas; Giniūnas, Linas; Vengris, Mikas

    2017-12-01

    In this study, we present the development and characterization of Cu plasma X-ray source driven by 20 W average power high repetition rate femtosecond laser in ambient atmosphere environment. The peak Cu- Kα photon flux of 2.3 × 109 photons/s into full solid angle is demonstrated (with a process conversion efficiency of 10-7), using pulses with peak intensity of 4.65 × 1014 W/cm2. Such Cu- Kα flux is significantly larger than others found in comparable experiments, performed in air environment. The effects of resonance plasma absorption process, when optimized, are shown to increase measured flux by the factor of 2-3. The relationship between X-ray photon flux and plasma-driving pulse repetition rate is quasi-linear, suggesting that fluxes could further be increased to 1010 photons/s using even higher average powers of driving radiation. These results suggest that to fully utilize the potential of high repetition rate laser sources, novel target material delivery systems (for example, jet-based ones) are required. On the other hand, this study demonstrates that high energy lasers currently used for plasma X-ray sources can be conveniently and efficiently replaced by high average power and repetition rate laser radiation, as a way to increase the brightness of the generated X-rays.

  17. A study of HANARO core conversion using high density U-Mo fuel

    International Nuclear Information System (INIS)

    Lee, K.H.; Lee, C.S.; Lee, B.C.; Park, S.J.; Kim, H.; Kim, C.K.

    2002-01-01

    Currently, HANARO is using 3.15gU/cc U3Si/Al as a driver fuel. HANARO has seven vertical irradiation holes in the core region. Three of them including a central trap are located in the inner region of the core and mainly being used for material irradiation tests. Four of them are located in the reflector tank but cooled by primary coolant. They are used for fuel irradiation tests or radioisotope development tests. For minimum core modification using high density U-Mo fuels, no dimension change is assumed in the current fuel rods and the cladding thickness remains the same in this study. The high density U-Mo fuel will have up to about twice the linear uranium loading of a current HANARO driver fuel. Using this high density fuel 8 fuel sites can be replaced with irradiation sites. Three kinds of conceptual cores are considered using 5 gU/cc U-7Mo/Al and 16 gU/cc U-7Mo. The increase of the linear heat generation rate due to the decrease of total fuel length can be overcome by more uniform radial and axial power distribution using different uranium densities and different fuel meat diameters are introduced into those cores. The new core has 4.54 times larger surface-to-volume ratio than the reference core. The core uranium loading, linear heat generation rate, excess reactivity, and control rod worth as well as the neutron spectra are analysed for each core. (author)

  18. Sustainability Aspects of Energy Conversion in Modern High-Speed Trains with Traction Induction Motors

    OpenAIRE

    Marc A. Rosen; Doru A. Nicola; Cornelia A. Bulucea; Daniel C. Cismaru

    2015-01-01

    Some aspects are illustrated of energy conversion processes during the operation of electric railway vehicles with traction induction motors, in order to support transport systems’ sustainability. Increasing efforts are being expended to enhance the sustainability of transportation technologies and systems. Since electric drive systems are used with variable voltage variable frequency (VVVF) inverters and traction induction motors, these machines with appropriate controls can realize both tra...

  19. Conversion and Blending Facility highly enriched uranium to low enriched uranium as metal. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-05

    The mission of this Conversion and Blending Facility (CBF) will be to blend surplus HEU metal and alloy with depleted uranium metal to produce an LEU product. The primary emphasis of this blending operation will be to destroy the weapons capability of large, surplus stockpiles of HEU. The blended LEU product can only be made weapons capable again by the uranium enrichment process. The blended LEU will be produced as a waste suitable for storage or disposal.

  20. Conversion and Blending Facility highly enriched uranium to low enriched uranium as metal. Revision 1

    International Nuclear Information System (INIS)

    1995-01-01

    The mission of this Conversion and Blending Facility (CBF) will be to blend surplus HEU metal and alloy with depleted uranium metal to produce an LEU product. The primary emphasis of this blending operation will be to destroy the weapons capability of large, surplus stockpiles of HEU. The blended LEU product can only be made weapons capable again by the uranium enrichment process. The blended LEU will be produced as a waste suitable for storage or disposal

  1. Effect of the silvicultural treatment on canopy properties, litter and seed production in beech coppices under conversion to high forest.

    Directory of Open Access Journals (Sweden)

    Andrea Cutini

    2010-12-01

    Full Text Available European beech (Fagus sylvatica L. is widely distributed in Italy where it covers 1035103 ha, mainly concentrated in the mountainous areas at altitudes above 900 m. The major part is represented by high forest often issued from the conversion of coppice woods, which in the past was the silvicultural system most widely applied mainly to provide fire wood. The social changes occurred in the second half of the last century –fire wood market crisis and the increasing importance of environmental issues- enhanced the conversion into high forest of large areas previously managed as coppice by means of different silvicultural treatments and practices. Nevertheless, the environmental benefits of this choice were not adequately investigated. Results of annual measurements (1992-2009 made in a beech coppice stand aged 65 are here reported. The study area is located on the Alpe di Catenaia, a pre-Apennine outcrop close to Arezzo (Central Italy. Variables strictly related to stand productivity and dynamics such as annual litter and seed production, leaf area index (LAI and transmittance (PAR were measured in the research area of Buca Zamponi to estimate the effects of two theses, natural evolution (TEST and conversion into high forest (DIR. Three thinnings were undertaken in the latter thesis in 1972, 1987 and 2002. Additional theses of natural evolution (CONTR and advance seed cutting (TS were added in 2002 in a nearby study area (Eremo della Casella. Results showed the high productivity of coppice stands, under conversion to high forest, with mean values of annual total litter, leaf litter and leaf area index of 5 Mg ha-1, 3 Mg ha-1 and 6 m2m-2, respectively. These findings confirm both the prompt response of beech to intensive thinning cycles and the reliability of undertaking coppice conversion into high forest. Furthermore, the positive trend observed in the ecological parameters and the high consistency of leaf fraction, highlight the still juvenile

  2. Rates and predictors of remission, recurrence and conversion to bipolar disorder after the first lifetime episode of depression--a prospective 5-year follow-up study.

    Science.gov (United States)

    Bukh, J D; Andersen, P K; Kessing, L V

    2016-04-01

    In depression, non-remission, recurrence of depressive episodes after remission and conversion to bipolar disorder are crucial determinants of poor outcome. The present study aimed to determine the cumulative incidences and clinical predictors of these long-term outcomes after the first lifetime episode of depression. A total of 301 in- or out-patients aged 18-70 years with a validated diagnosis of a single depressive episode were assessed from 2005 to 2007. At 5 years of follow-up, 262 patients were reassessed by means of the life chart method and diagnostic interviews from 2011 to 2013. Cumulative incidences and the influence of clinical variables on the rates of remission, recurrence and conversion to bipolar disorder, respectively, were estimated by survival analysis techniques. Within 5 years, 83.3% obtained remission, 31.5% experienced recurrence of depression and 8.6% converted to bipolar disorder (6.3% within the first 2 years). Non-remission increased with younger age, co-morbid anxiety and suicidal ideations. Recurrence increased with severity and treatment resistance of the first depression, and conversion to bipolar disorder with treatment resistance, a family history of affective disorder and co-morbid alcohol or drug abuse. The identified clinical characteristics of the first lifetime episode of depression should guide patients and clinicians for long-term individualized tailored treatment.

  3. Research reactor core conversion from the use of highly enriched uranium to the use of low enriched uranium fuels guidebook

    International Nuclear Information System (INIS)

    1980-08-01

    In view of the proliferation concerns caused by the use of highly enriched uranium (HEU) and in anticipation that the supply of HEU to research and test reactors will be more restricted in the future, this document has been prepared to assist reactor operators in determining whether conversion to the use of low enriched uranium (LEU) fuel designs is technically feasible for their specific reactor, and to assist in making a smooth transition to the use of LEU fuel designs where appropriate

  4. Low nitrous oxide production through nitrifier-denitrification in intermittent-feed high-rate nitritation reactors

    DEFF Research Database (Denmark)

    Su, Qingxian; Ma, Chun; Domingo-Felez, Carlos

    2017-01-01

    Nitrous oxide (N2O) production from autotrophic nitrogen conversion processes, especially nitritation systems, can be significant, requires understanding and calls for mitigation. In this study, the rates and pathways of N2O production were quantified in two lab-scale sequencing batch reactors...... to maintain high nitritation efficiency and high nitritation rates at 20-26 °C over a period of ∼300 days. Even at the high nitritation efficiencies, net N2O production was low (∼2% of the oxidized ammonium). Net N2O production rates transiently increased with a rise in pH after each feeding, suggesting...... operated with intermittent feeding and demonstrating long-term and high-rate nitritation. The resulting reactor biomass was highly enriched in ammonia-oxidizing bacteria, and converted ∼93 ± 14% of the oxidized ammonium to nitrite. The low DO set-point combined with intermittent feeding was sufficient...

  5. High-rate performance of muon drift tube detectors

    International Nuclear Information System (INIS)

    Schwegler, Philipp

    2014-01-01

    The Large Hadron Collider (LHC) at the European Centre for Particle Physics, CERN, collides protons with an unprecedentedly high centre-of-mass energy and luminosity. The collision products are recorded and analysed by four big experiments, one of which is the ATLAS detector. In parallel with the first LHC run from 2009 to 2012, which culminated in the discovery of the last missing particle of the Standard Model of particle physics, the Higgs boson, planning of upgrades of the LHC for higher instantaneous luminosities (HL-LHC) is already progressing. The high instantaneous luminosity of the LHC puts high demands on the detectors with respect to radiation hardness and rate capability which are further increased with the luminosity upgrade. In this thesis, the limitations of the Muon Drift Tube (MDT) chambers of the ATLAS Muon Spectrometer at the high background counting rates at the LHC and performance of new small diameter muon drift tube (sMDT) detectors at the even higher background rates at HL-LHC are studied. The resolution and efficiency of sMDT chambers at high γ-ray and proton irradiation rates well beyond the ones expected at HL-LHC have been measured and the irradiation effects understood using detailed simulations. The sMDT chambers offer an about an order of magnitude better rate capability and are an ideal replacement for the MDT chambers because of compatibility of services and read-out. The limitations of the sMDT chambers are now in the read-out electronics, taken from the MDT chambers, to which improvements for even higher rate capability are proposed.

  6. High Strain Rate Tensile Testing of Silver Nanowires: Rate-Dependent Brittle-to-Ductile Transition.

    Science.gov (United States)

    Ramachandramoorthy, Rajaprakash; Gao, Wei; Bernal, Rodrigo; Espinosa, Horacio

    2016-01-13

    The characterization of nanomaterials under high strain rates is critical to understand their suitability for dynamic applications such as nanoresonators and nanoswitches. It is also of great theoretical importance to explore nanomechanics with dynamic and rate effects. Here, we report in situ scanning electron microscope (SEM) tensile testing of bicrystalline silver nanowires at strain rates up to 2/s, which is 2 orders of magnitude higher than previously reported in the literature. The experiments are enabled by a microelectromechanical system (MEMS) with fast response time. It was identified that the nanowire plastic deformation has a small activation volume (ductile failure mode transition was observed at a threshold strain rate of 0.2/s. Transmission electron microscopy (TEM) revealed that along the nanowire, dislocation density and spatial distribution of plastic regions increase with increasing strain rate. Furthermore, molecular dynamic (MD) simulations show that deformation mechanisms such as grain boundary migration and dislocation interactions are responsible for such ductility. Finally, the MD and experimental results were interpreted using dislocation nucleation theory. The predicted yield stress values are in agreement with the experimental results for strain rates above 0.2/s when ductility is pronounced. At low strain rates, random imperfections on the nanowire surface trigger localized plasticity, leading to a brittle-like failure.

  7. Photoelectrochemical Complexes of Fucoxanthin-Chlorophyll Protein for Bio-Photovoltaic Conversion with a High Open-Circuit Photovoltage.

    Science.gov (United States)

    Zhang, Tianning; Liu, Cheng; Dong, Wenjing; Wang, Wenda; Sun, Yan; Chen, Xin; Yang, Chunhong; Dai, Ning

    2017-12-05

    Open-circuit photovoltage (V oc ) is among the critical parameters for achieving an efficient light-to-charge conversion in existing solar photovoltaic devices. Natural photosynthesis exploits light-harvesting chlorophyll (Chl) protein complexes to transfer sunlight energy efficiently. We describe the exploitation of photosynthetic fucoxanthin-chlorophyll protein (FCP) complexes for realizing photoelectrochemical cells with a high V oc . An antenna-dependent photocurrent response and a V oc up to 0.72 V are observed and demonstrated in the bio-photovoltaic devices fabricated with photosynthetic FCP complexes and TiO 2 nanostructures. Such high V oc is determined by fucoxanthin in FCP complexes, and is rarely found in photoelectrochemical cells with other natural light-harvesting antenna. We think that the FCP-based bio-photovoltaic conversion will provide an opportunity to fabricate environmental benign photoelectrochemical cells with high V oc , and also help improve the understanding of the essential physics behind the light-to-charge conversion in photosynthetic complexes. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Highly photoluminescent and photostable CdSe quantum dot-nylon hybrid composites for efficient light conversion applications

    Energy Technology Data Exchange (ETDEWEB)

    Yuan Ying; Riehle, Frank-Stefan [Freiburg Materials Research Centre (FMF), University of Freiburg, Stefan-Meier-Str. 21, D-79104 Freiburg (Germany); Department of Microsystems Engineering (IMTEK), Georg Koehler Allee 103, University of Freiburg, D-79110 Freiburg (Germany); Nitschke, Roland [Life Imaging Center, Centre of Systems Biology, University of Freiburg Habsburgerstr. 49, D-79104 Freiburg (Germany); Centre for Biological Signalling Studies (BIOSS), University of Freiburg (Germany); Krueger, Michael, E-mail: michael.krueger@fmf.uni-freiburg.de [Freiburg Materials Research Centre (FMF), University of Freiburg, Stefan-Meier-Str. 21, D-79104 Freiburg (Germany); Department of Microsystems Engineering (IMTEK), Georg Koehler Allee 103, University of Freiburg, D-79110 Freiburg (Germany)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer A novel in situ synthesis approach for highly luminescent CdSe core QDs-nylon hybrid materials. Black-Right-Pointing-Pointer Potential applications for light and energy conversion are demonstrated. Black-Right-Pointing-Pointer Three dimensional structures out of this hybrid material are available. - Abstract: Highly photoluminescent hexadecylamine (HDA) capped core CdSe quantum dots (QDs) with fluorescent quantum yields (QYs) up to 60% were synthesized using a hot injection method and directly incorporated into nylon polymer. For the incorporation of crude CdSe QDs into nylon a simple reproducible and upscalable one pot approach was developed without the need of further purification steps. The photoluminescence (PL) properties of the core QDs and the resulting QD-polymer hybrid composites were investigated and compared. Red emitting hybrid materials exhibit a QY of 60% with a high potential for applications in direct light and energy conversion. The hybrid materials could be successfully utilized as LED conversion layers. By avoiding exposure to oxygen the hybrid films can be kept for a month without detecting a significant decrease in luminescence. Various three dimensional structures are easily available opening doors for further applications such as novel materials for fluorescence standard development in laser scanning microscopy (LSM).

  9. Wavelength conversion, time demultiplexing and multicasting based on cross-phase modulation and four-wave mixing in dispersion-flattened highly nonlinear photonic crystal fiber

    International Nuclear Information System (INIS)

    Hui, Zhan-Qiang; Zhang, Jian-Guo

    2012-01-01

    We propose the use of cross-phase modulation (XPM) and four-wave mixing (FWM) in dispersion-flattened highly nonlinear photonic crystal fibers (HNL-PCFs) to implement the functionalities of wavelength conversion, simultaneous time demultiplexing and wavelength multicasting in optical time-division multiplexing (OTDM) systems. The experiments on wavelength conversion at 80 Gbit s −1 and OTDM demultiplexing from 80 to 10 Gbit s −1 with wavelength multicasting of two channels are successfully demonstrated to validate the proposed scheme, which are carried out by using two segments of dispersion-flattened HNL-PCFs with lengths of 100 and 50 m, respectively. Moreover, the bit error rate (BER) performance is also measured. The results show that our designed system can achieve a power penalty of less than 4.6 dB for two multicasting channels with a 24 nm wavelength span at the BER of 10 −9 when compared with the 10 Gbit/s back-to-back measurement. The proposed system is transparent to bit rate since only an ultrafast third-order nonlinear effect is used. The resulting configuration is compact, robust and reliable, benefiting from the use of dispersion-flattened HNL-PCFs with short lengths. This also makes the proposed system more flexible in the operational wavelengths than those based on dispersion-shifted fibers and traditional highly nonlinear fibers. (paper)

  10. Exhaustive Conversion of Inorganic Nitrogen to Nitrogen Gas Based on a Photoelectro-Chlorine Cycle Reaction and a Highly Selective Nitrogen Gas Generation Cathode.

    Science.gov (United States)

    Zhang, Yan; Li, Jinhua; Bai, Jing; Shen, Zhaoxi; Li, Linsen; Xia, Ligang; Chen, Shuai; Zhou, Baoxue

    2018-02-06

    A novel method for the exhaustive conversion of inorganic nitrogen to nitrogen gas is proposed in this paper. The key properties of the system design included an exhaustive photoelectrochemical cycle reaction in the presence of Cl - , in which Cl· generated from oxidation of Cl - by photoholes selectively converted NH 4 + to nitrogen gas and some NO 3 - or NO 2 - . The NO 3 - or NO 2 - was finally reduced to nitrogen gas on a highly selective Pd-Cu-modified Ni foam (Pd-Cu/NF) cathode to achieve exhaustive conversion of inorganic nitrogen to nitrogen gas. The results indicated total nitrogen removal efficiencies of 30 mg L -1 inorganic nitrogen (NO 3 - , NH 4 + , NO 3 - /NH 4 + = 1:1 and NO 2 - /NO 3 - /NH 4 + = 1:1:1) in 90 min were 98.2%, 97.4%, 93.1%, and 98.4%, respectively, and the remaining nitrogen was completely removed by prolonging the reaction time. The rapid reduction of nitrate was ascribed to the capacitor characteristics of Pd-Cu/NF that promoted nitrate adsorption in the presence of an electric double layer, eliminating repulsion between the cathode and the anion. Nitrate was effectively removed with a rate constant of 0.050 min -1 , which was 33 times larger than that of Pt cathode. This system shows great potential for inorganic nitrogen treatment due to the high rate, low cost, and clean energy source.

  11. Conversion of straight-run gas-condensate benzenes into high- octane gasolines based on modified ZSM-5 zeolites

    International Nuclear Information System (INIS)

    Erofeev, V; Reschetilowski, V; Khomajakov, I; Egorova, L; Volgina, T; Tatarkina, A

    2014-01-01

    This paper describes the conversion of straight-run benzene of gas condensate into high-octane gasoline based on zeolite catalyst ZSM-5, modified in binary system oxide- based Sn (III) and Bi (III). It was defined that the introduction of the binary system oxide-based Sn(III) and Bi (III) into the basic zeolite results in the 2-fold increase of its catalytic activity.High-octane gasoline converted from straight-run benzene is characterized by a low benzol content in comparison to the high-octane benzenes produced during the catalytic reforming

  12. High substrate uptake rates empower Vibrio natriegens as production host for industrial biotechnology.

    Science.gov (United States)

    Hoffart, Eugenia; Grenz, Sebastian; Lange, Julian; Nitschel, Robert; Müller, Felix; Schwentner, Andreas; Feith, André; Lenfers-Lücker, Mira; Takors, Ralf; Blombach, Bastian

    2017-09-08

    The productivity of industrial fermentation processes is essentially limited by the biomass specific substrate consumption rate (q S ) of the applied microbial production system. Since q S depends on the growth rate (μ), we highlight the potential of the fastest growing non-pathogenic bacterium, Vibrio natriegens , as novel candidate for future biotechnological processes. V. natriegens grows rapidly in BHIN complex medium with a μ of up to 4.43 h -1 (doubling time of 9.4 min) as well as in minimal medium supplemented with various industrially relevant substrates. Bioreactor cultivations in minimal medium with glucose showed that V. natriegens possesses an exceptionally high q S under aerobic (3.90 ± 0.08 g g -1 h -1 ) and anaerobic (7.81 ± 0.71 g g -1 h -1 ) conditions. Fermentations with resting cells of genetically engineered V. natriegens under anaerobic conditions yielded an overall volumetric productivity of 0.56 ± 0.10 g alanine L -1 min -1 (i.e. 34 g L -1 h -1 ). These inherent properties render V. natriegens a promising new microbial platform for future industrial fermentation processes operating with high productivity. Importance Low conversion rates are one major challenge to realize microbial fermentation processes for the production of commodities operating competitively to existing petrochemical approaches. For this reason, we screened for a novel platform organism possessing superior characteristics to traditionally employed microbial systems. We identified the fast growing Vibrio natriegens which exhibits a versatile metabolism and shows striking growth and conversion rates, as a solid candidate to reach outstanding productivities. Due to these inherent characteristics V. natriegens can speed up common laboratory routines, is suitable for already existing production procedures, and forms an excellent foundation to engineer next generation bioprocesses. Copyright © 2017 American Society for Microbiology.

  13. High data rate coding for the space station telemetry links.

    Science.gov (United States)

    Lumb, D. R.; Viterbi, A. J.

    1971-01-01

    Coding systems for high data rates were examined from the standpoint of potential application in space-station telemetry links. Approaches considered included convolutional codes with sequential, Viterbi, and cascaded-Viterbi decoding. It was concluded that a high-speed (40 Mbps) sequential decoding system best satisfies the requirements for the assumed growth potential and specified constraints. Trade-off studies leading to this conclusion are viewed, and some sequential (Fano) algorithm improvements are discussed, together with real-time simulation results.

  14. Predicting High Frequency Exchange Rates using Machine Learning

    OpenAIRE

    Palikuca, Aleksandar; Seidl,, Timo

    2016-01-01

    This thesis applies a committee of Artificial Neural Networks and Support Vector Machines on high-dimensional, high-frequency EUR/USD exchange rate data in an effort to predict directional market movements on up to a 60 second prediction horizon. The study shows that combining multiple classifiers into a committee produces improved precision relative to the best individual committee members and outperforms previously reported results. A trading simulation implementing the committee classifier...

  15. Decay rate of the false vacuum at high tempratures

    International Nuclear Information System (INIS)

    Eboli, O.J.P.; Marques, G.C.

    1984-01-01

    Within the semiclassical approach, the high temperaure behaviour of the decay rate of the metastable vacuum in Field Theory is investigated. It is shown that, contrarily to what has been proposed in the literature, the pre-exponential factor exhibits a nontrivial dependence on the temperature. Furthermore, this dependence is such that at very high temperatures it is as important as the exponential factor and consequently it spoils many conclusions drawn up to now on Cosmological Phase Transitions. (Author) [pt

  16. Electrophoretic Deposition of Gallium with High Deposition Rate

    Directory of Open Access Journals (Sweden)

    Hanfei Zhang

    2014-12-01

    Full Text Available In this work, electrophoretic deposition (EPD is reported to form gallium thin film with high deposition rate and low cost while avoiding the highly toxic chemicals typically used in electroplating. A maximum deposition rate of ~0.6 μm/min, almost one order of magnitude higher than the typical value reported for electroplating, is obtained when employing a set of proper deposition parameters. The thickness of the film is shown to increase with deposition time when sequential deposition is employed. The concentration of Mg(NO32, the charging salt, is also found to be a critical factor to control the deposition rate. Various gallium micropatterns are obtained by masking the substrate during the process, demonstrating process compatibility with microfabrication. The reported novel approach can potentially be employed in a broad range of applications with Ga as a raw material, including microelectronics, photovoltaic cells, and flexible liquid metal microelectrodes.

  17. Wavelength conversion techniques and devices

    DEFF Research Database (Denmark)

    Danielsen, Søren Lykke; Mikkelsen, Benny; Hansen, Peter Bukhave

    1997-01-01

    Taking into account the requirements to the converters e.g., bit rate transparency (at least up to 10 Gbit/s), polarisation independence, wavelength independence, moderate input power levels, high signal-to-noise ratio and high extinction ratio interferometric wavelength convertors are very...... interesting for use in WDM optical fibre networks. However, the perfect converter has probably not yet been fabricated and new techniques such as conversion relying on cross-absorption modulation in electro-absorption modulators might also be considered in pursue of effective conversion devices...

  18. Technical basis in support of the conversion of the University of Missouri Research Reactor (MURR) core from highly-enriched to low-enriched uranium - core neutron physics

    Energy Technology Data Exchange (ETDEWEB)

    Stillman, J. [Argonne National Lab. (ANL), Argonne, IL (United States); Feldman, E. [Univ. of Missouri, Columbia, MO (United States). Columbia Research Reactor; Foyto, L [Univ. of Missouri, Columbia, MO (United States). Columbia Research Reactor; Kutikkad, K [Univ. of Missouri, Columbia, MO (United States). Columbia Research Reactor; McKibben, J C [Univ. of Missouri, Columbia, MO (United States). Columbia Research Reactor; Peters, N. [Univ. of Missouri, Columbia, MO (United States). Columbia Research Reactor; Stevens, J. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2012-09-01

    This report contains the results of reactor design and performance for conversion of the University of Missouri Research Reactor (MURR) from the use of highly-enriched uranium (HEU) fuel to the use of low-enriched uranium (LEU) fuel. The analyses were performed by staff members of the Global Threat Reduction Initiative (GTRI) Reactor Conversion Program at the Argonne National Laboratory (ANL) and the MURR Facility. The core conversion to LEU is being performed with financial support of the U. S. government.

  19. READOUT ELECTRONICS FOR A HIGH-RATE CSC DETECTOR

    International Nuclear Information System (INIS)

    OCONNOR, P.; GRATCHEV, V.; KANDASAMY, A.; POLYCHRONAKOS, V.; TCHERNIATINE, V.; PARSONS, J.; SIPPACH, W.

    1999-01-01

    A readout system for a high-rate muon Cathode Strip Chamber (CSC) is described. The system, planned for use in the forward region of the ATLAS muon spectrometer, uses two custom CMOS integrated circuits to achieve good position resolution at a flux of up to 2,500 tracks/cm 2 /s

  20. Digital approach to high rate gamma-ray spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Korolczuk, Stefan; Mianowski, Slawomir; Rzadkiewicz, Jacek; Sibczynski, Pawel; Swiderski, Lukasz; Szewinski, Jaroslaw; Zychor, Izabella [Narodowe Centrum Badan Jadrowych (NCBJ), 05-400 Otwock, (Poland)

    2015-07-01

    Basic concepts and preliminary results of creating high rate digital spectrometry system using efficient ADCs and latest FPGA are presented as well as a comparison with commercially available devices. The possibility to use such systems, coupled to scintillators, in plasma experiments is discussed. (authors)

  1. High rate of teenage pregnancy and sexually transmitted infections ...

    African Journals Online (AJOL)

    There is increased in teenage pregnancy despite the presence of dual protection practice and health care awareness programmes related to health and sexuality education in South Africa. The present study explores the underlying causes of high teenage pregnancy and sexually transmitted diseases rates, including HIV ...

  2. Twinning in copper deformed at high strain rates

    Indian Academy of Sciences (India)

    Abstract. Copper samples having varying microstructures were deformed at high strain rates using a split-. Hopkinson pressure bar. Transmission electron microscopy results show deformation twins present in samples that were both annealed and strained, whereas samples that were annealed and left unstrained, as well ...

  3. High Frame Rate Synthetic Aperture 3D Vector Flow Imaging

    DEFF Research Database (Denmark)

    Villagómez Hoyos, Carlos Armando; Holbek, Simon; Stuart, Matthias Bo

    2016-01-01

    , current volumetric ultrasonic flow methods are limited to one velocity component or restricted to a reduced field of view (FOV), e.g. fixed imaging planes, in exchange for higher temporal resolutions. To solve these problems, a previously proposed accurate 2-D high frame rate vector flow imaging (VFI...

  4. Sphaleron rate at high temperature in 1+1 dimensions

    International Nuclear Information System (INIS)

    Smit, Jan; Tang, W.H.

    1999-01-01

    We resolve the controversy in the high temperature behavior of the sphaleron rate in the abelian Higgs model in 1+1 dimensions. The T 2 behavior at intermediate lattice spacings is found to change into T ((2)/(3)) behavior in the continuum limit. The results are supported by analytic arguments that the classical approximation is good for this model

  5. Highly Controlled Codeposition Rate of Organolead Halide Perovskite by Laser Evaporation Method.

    Science.gov (United States)

    Miyadera, Tetsuhiko; Sugita, Takeshi; Tampo, Hitoshi; Matsubara, Koji; Chikamatsu, Masayuki

    2016-10-05

    Organolead-halide perovskites can be promising materials for next-generation solar cells because of its high power conversion efficiency. The method of precise fabrication is required because both solution-process and vacuum-process fabrication of the perovskite have problems of controllability and reproducibility. Vacuum deposition process was expected to achieve precise control; however, vaporization of amine compound significantly degrades the controllability of deposition rate. Here we achieved the reduction of the vaporization by implementing the laser evaporation system for the codeposition of perovskite. Locally irradiated continuous-wave lasers on the source materials realized the reduced vaporization of CH 3 NH 3 I. The deposition rate was stabilized for several hours by adjusting the duty ratio of modulated laser based on proportional-integral control. Organic-photovoltaic-type perovskite solar cells were fabricated by codeposition of PbI 2 and CH 3 NH 3 I. A power-conversion efficiency of 16.0% with reduced hysteresis was achieved.

  6. High production rate of IBAD-MgO buffered substrate

    Energy Technology Data Exchange (ETDEWEB)

    Yoshizumi, M., E-mail: myoshizumi@istec.or.j [Superconductivity Research Laboratory, ISTEC, Shinonome 1-10-13, Koto-ku, Tokyo 135-0062 (Japan); Miyata, S.; Ibi, A.; Fukushima, H.; Yamada, Y.; Izumi, T.; Shiohara, Y. [Superconductivity Research Laboratory, ISTEC, Shinonome 1-10-13, Koto-ku, Tokyo 135-0062 (Japan)

    2009-10-15

    The conventional IBAD (Ion Beam Assisted Deposition) process using fluorite materials yields low production rates, resulting in high production cost, which reduces the motivation for practical application in spite of its high quality. The IBAD process using rock salt materials, e.g. MgO, is well known as a strong candidate of practical application due to its potential of high production rate and high in-plane grain alignment. In this work, the IBAD-MgO process was investigated for a newly developed architecture of PLD (Pulsed Laser Deposition)-CeO{sub 2}/sputter-LMO (LaMnO{sub 3})/IBAD-MgO/sputter-GZO (Gd{sub 2}Zr{sub 2}O{sub 7})/Hastelloy{sup TM} to make long buffered metal tapes with high properties and a high production rate. The 50 m-long IBAD-MgO substrates with about 4 deg. of DELTAphiCeO{sub 2} in an XRD phi scan could be fabricated repeatedly. A GdBCO (GdBa{sub 2}Cu{sub 3}O{sub x}) layer deposited on the buffered substrate showed the minimum I{sub c} value of 325 A/cm-w in a 41 m-long tape. Almost of the tape showed 500-600 A/cm-w of I{sub c} value. The deposition time for the IBAD-MgO layer was 60 s which was about 2 orders of magnitude shorter than the conventional IBAD process. The production rate of 24 m/h was realized at the IBAD-MgO process to fabricate the GdBCO coated conductor with high J{sub c} and I{sub c} properties.

  7. Studies on conversion of crude sodium diuranate to high purity uranium oxide by chemical route

    International Nuclear Information System (INIS)

    Rajan, K.C.; Ramadevi, G.; Giri, Nitai; Chakravartty, J.K.; Sreenivas, T.

    2016-01-01

    Uranium values are recovered from ores and mine rejects by employing chemical processing methods. The process chemistry could be either acidic (H 2 SO 4 medium) or alkaline (Na 2 CO 3 - NaHCO 3 medium) based depending on the nature of host rock. The end product is termed as 'yellow cake' which is sent to refining plants for final purification and fuel manufacture. Conventionally the yellow cake product is magnesium (MDU) or ammonium diuranate (ADU) in U-plants following the acidic processing route while it is sodium diuranate (SDU) in the alkaline route. The preference for SDU in plants operating with alkaline route is mainly driven by the requirement of conserving and reusing the expensive chemicals. Though alkaline processing gives relatively purer diuranate product, the practice of direct precipitation of dissolved uranium from pregnant leach liquors invariably leads to presence of impurities detrimental for downstream unit operations, mostly in solvent extraction based refining stages. In this score uranium peroxide is superior to other uranates in many respects. Two alternatives are practiced for the conversion of SDU to uranium peroxide - chemical and fluid bed precipitation. Though generic flowsheet for the conversion stage is well documented, the process conditions and complexities vary with the chemistry of the pregnant leach liquor which is specific for a given ore or a deposit. This paper discusses the process scheme tailored, optimized and tested on a kilo-gram scale for chemical conversion of SDU produced by alkaline processing of a low-grade carbonate hosted uranium ore. The entire process scheme is first of its kind in Indian uranium ore processing arena

  8. Physical nature of strain rate sensitivity of metals and alloys at high strain rates

    Science.gov (United States)

    Borodin, E. N.; Gruzdkov, A. A.; Mayer, A. E.; Selyutina, N. S.

    2018-04-01

    The role of instabilities of plastic flow at plastic deformation of various materials is one of the important cross-disciplinary problems which is equally important in physics, mechanics and material science. The strain rate sensitivities under slow and high strain rate conditions of loading have different physical nature. In the case of low strain rate, the sensitivity arising from the inertness of the defect structures evolution can be expressed by a single parameter characterizing the plasticity mechanism. In our approach, this is the value of the characteristic relaxation time. In the dynamic case, there are additional effects of “high-speed sensitivity” associated with the micro-localization of the plastic flow near the stress concentrators. In the frames of mechanical description, this requires to introduce additional strain rate sensitivity parameters, which is realized in numerous modifications of Johnson–Cook and Zerilli–Armstrong models. The consideration of both these factors is fundamental for an adequate description of the problems of dynamic deformation of highly inhomogeneous metallic materials such as steels and alloys. The measurement of the dispersion of particle velocities on the free surface of a shock-loaded material can be regarded as an experimental expression of the effect of micro-localization. This is also confirmed by our results of numerical simulation of the propagation of shock waves in a two-dimensional formulation and analytical estimations.

  9. Mode conversion of lower hybrid waves at high ion cyclotron harmonics. Appendix F

    International Nuclear Information System (INIS)

    Swanson, D.G.; Cho, S.

    1985-05-01

    The problem of ion cyclotron harmonic absorption for a lower hybrid wave is shown to be a mode conversion problem. A new form of the dispersion relation is developed and then expanded to get a differential equation identical to that for the second harmonic problem. The validity of this model is restricted to the region far from the lower hybrid resonance layer. It is shown that mode couplings occur among the incident cold wave and two other waves, and the tunneling factor becomes singular there

  10. Process for the aerobic conversion of poultry manure into high-protein feedstuff

    Energy Technology Data Exchange (ETDEWEB)

    Shuler, M.L.; Roberts, E.D.; Mitchell, D.W.; Kargi, F.; Austic, R.E.; Henry, A.; Vashon, R.; Seeley, H.W. Jr.

    1979-01-01

    A two-stage aerobic continuous process is suggested for the conversion of poultry waste into a single-cell protein (SCP) product. The technical feasibility of the process is examined in this paper. Using bench-scale apparatus the approximate growth kinetics have been discovered. Possible modes of product recovery have been examined. The product consists primarily of a strain of Pseudomonas fluorescens which has a lysine-rich (approx. 9.3%) amino acid profile that could make this product an attractive feed ingredient for poultry diets.

  11. High-speed conversion of carbon dioxide into methanol using catalyst. Shokubai ni yoru nisanka tanso no kosoku methanol ka

    Energy Technology Data Exchange (ETDEWEB)

    Inui, T. (Kyoto University, Kyoto (Japan). Faculty of Enineering)

    1993-02-01

    This paper describes high-speed conversion of CO2 into methanol. When a Cu-Zn-Cr-Al oxide-based catalyst (MSCp catalyst) prepared by using a sedimentation process used for synthesizing methanol from CO is applied to converting CO2 into methanol, the methanol yield decreases down to a several fraction of CO to methanol conversion, with a possibility of greater catalytic deactivation. If this catalyst prepared by using a homogeneous gelation process (MSCg catalyst) is used, the yield of methanol from CO2 increases by 240 plus percent over the case of using the MSCp catalyst, and no catalytic deactivation occurs at all during a use for ten and odd hours. Further, when La2O3 is added to the MSCg catalyst at 4% by weight, the methanol yield increases by about two times as much as the case without addition, and the temperature at which the maximum yield is achieved shifts to a lower temperature side by about 20[degree]C. Combining Ag or Pd with the MSCg catalyst provides the same effects. The paper touches on an attempt of high-speed CO2 conversion using this catalyst loaded with ceramic fibers. 15 refs., 5 figs., 2 tabs.

  12. Radiation shielding and dose rate distribution for the building of the high dose rate accelerator

    International Nuclear Information System (INIS)

    Matsuda, Koji; Takagaki, Torao; Nakase, Yoshiaki; Nakai, Yohta.

    1984-03-01

    A high dose rate electron accelerator was established at Osaka Laboratory for Radiation Chemistry, Takasaki Establishment, JAERI in the fiscal year of 1975. This report shows the fundamental concept for the radiation shielding of the accelerator building and the results of their calculations which were evaluated through the model experiments. After the construction of the building, the leak radiation was measured in order to evaluate the calculating method of radiation shielding. Dose rate distribution of X-rays was also measured in the whole area of the irradiation room as a data base. (author)

  13. Optimization and phase matching of fiber-laser-driven high-order harmonic generation at high repetition rate.

    Science.gov (United States)

    Cabasse, Amélie; Machinet, Guillaume; Dubrouil, Antoine; Cormier, Eric; Constant, Eric

    2012-11-15

    High-repetition-rate sources are very attractive for high-order harmonic generation (HHG). However, due to their pulse characteristics (low energy, long duration), those systems require a tight focusing geometry to achieve the necessary intensity to generate harmonics. In this Letter, we investigate theoretically and experimentally the optimization of HHG in this geometry, to maximize the extreme UV (XUV) photon flux and improve the conversion efficiency. We analyze the influence of atomic gas media (Ar, Kr, or Xe), gas pressure, and interaction geometries (a gas jet and a finite and a semi-infinite gas cell). Numerical simulations allow us to define optimal conditions for HHG in this tight focusing regime and to observe the signature of on-axis phase matching. These conditions are implemented experimentally using a high-repetition-rate Yb-doped fiber laser system. We achieve optimization of emission with a recorded XUV photon flux of 4.5×10(12) photons/s generated in Xe at 100 kHz repetition rate.

  14. Efficient continuous-wave nonlinear frequency conversion in high-Q gallium nitride photonic crystal cavities on silicon

    Directory of Open Access Journals (Sweden)

    Mohamed Sabry Mohamed

    2017-03-01

    Full Text Available We report on nonlinear frequency conversion from the telecom range via second harmonic generation (SHG and third harmonic generation (THG in suspended gallium nitride slab photonic crystal (PhC cavities on silicon, under continuous-wave resonant excitation. Optimized two-dimensional PhC cavities with augmented far-field coupling have been characterized with quality factors as high as 4.4 × 104, approaching the computed theoretical values. The strong enhancement in light confinement has enabled efficient SHG, achieving a normalized conversion efficiency of 2.4 × 10−3 W−1, as well as simultaneous THG. SHG emission power of up to 0.74 nW has been detected without saturation. The results herein validate the suitability of gallium nitride for integrated nonlinear optical processing.

  15. High strain-rate soft material characterization via inertial cavitation

    Science.gov (United States)

    Estrada, Jonathan B.; Barajas, Carlos; Henann, David L.; Johnsen, Eric; Franck, Christian

    2018-03-01

    Mechanical characterization of soft materials at high strain-rates is challenging due to their high compliance, slow wave speeds, and non-linear viscoelasticity. Yet, knowledge of their material behavior is paramount across a spectrum of biological and engineering applications from minimizing tissue damage in ultrasound and laser surgeries to diagnosing and mitigating impact injuries. To address this significant experimental hurdle and the need to accurately measure the viscoelastic properties of soft materials at high strain-rates (103-108 s-1), we present a minimally invasive, local 3D microrheology technique based on inertial microcavitation. By combining high-speed time-lapse imaging with an appropriate theoretical cavitation framework, we demonstrate that this technique has the capability to accurately determine the general viscoelastic material properties of soft matter as compliant as a few kilopascals. Similar to commercial characterization algorithms, we provide the user with significant flexibility in evaluating several constitutive laws to determine the most appropriate physical model for the material under investigation. Given its straightforward implementation into most current microscopy setups, we anticipate that this technique can be easily adopted by anyone interested in characterizing soft material properties at high loading rates including hydrogels, tissues and various polymeric specimens.

  16. Miniaturized Stretchable and High-Rate Linear Supercapacitors

    Science.gov (United States)

    Zhu, Wenjun; Zhang, Yang; Zhou, Xiaoshuang; Xu, Jiang; Liu, Zunfeng; Yuan, Ningyi; Ding, Jianning

    2017-07-01

    Linear stretchable supercapacitors have attracted much attention because they are well suited to applications in the rapidly expanding field of wearable electronics. However, poor conductivity of the electrode material, which limits the transfer of electrons in the axial direction of the linear supercapacitors, leads to a serious loss of capacity at high rates. To solve this problem, we use gold nanoparticles to decorate aligned multiwall carbon nanotube to fabricate stretchable linear electrodes. Furthermore, we have developed fine stretchable linear supercapacitors, which exhibited an extremely high elasticity up to 400% strain with a high capacitance of about 8.7 F g-1 at the discharge current of 1 A g-1.

  17. HIGH-RATE ANAEROBIC TREATMENT OF ALCOHOLIC WASTEWATERS

    Directory of Open Access Journals (Sweden)

    Florencio L.

    1997-01-01

    Full Text Available Modern high-rate anaerobic wastewater treatment processes are rapidly becoming popular for industrial wastewater treatment. However, until recently stable process conditions could not be guaranteed for alcoholic wastewaters containing higher concentrations of methanol. Although methanol can be directly converted into methane by methanogens, under specific conditions it can also be converted into acetate and butyrate by acetogens. The accumulation of volatile fatty acids can lead to reactor instability in a weakly buffered reactor. Since this process was insufficiently understood, the application of high-rate anaerobic reactors was highly questionable. This research investigated the environmental factors that are of importance in the predominance of methylotrophic methanogens over acetogens in a natural mixed culture during anaerobic wastewater treatment in upflow anaerobic sludge bed reactors. Technological and microbiological aspects were investigated. Additionally, the route by which methanol is converted into methane is also presented

  18. Spallation model for the high strain rates range

    Science.gov (United States)

    Dekel, E.; Eliezer, S.; Henis, Z.; Moshe, E.; Ludmirsky, A.; Goldberg, I. B.

    1998-11-01

    Measurements of the dynamic spall strength in aluminum and copper shocked by a high power laser to pressures of hundreds of kbars show a rapid increase in the spall strength with the strain rate at values of about 107 s-1. We suggest that this behavior is a result of a change in the spall mechanism. At low strain rates the spall is caused by the motion and coalescence of material's initial flaws. At high strain rates there is not enough time for the flaws to move and the spall is produced by the formation and coalescence of additional cavities where the interatomic forces become dominant. Material under tensile stress is in a metastable condition and cavities of a critical radius are formed in it due to thermal fluctuations. These cavities grow due to the tension. The total volume of the voids grow until the material disintegrates at the spall plane. Simplified calculations based on this model, describing the metal as a viscous liquid, give results in fairly good agreement with the experimental data and predict the increase in spall strength at high strain rates.

  19. Highly variable rates of genome rearrangements between hemiascomycetous yeast lineages.

    Directory of Open Access Journals (Sweden)

    2006-03-01

    Full Text Available Hemiascomycete yeasts cover an evolutionary span comparable to that of the entire phylum of chordates. Since this group currently contains the largest number of complete genome sequences it presents unique opportunities to understand the evolution of genome organization in eukaryotes. We inferred rates of genome instability on all branches of a phylogenetic tree for 11 species and calculated species-specific rates of genome rearrangements. We characterized all inversion events that occurred within synteny blocks between six representatives of the different lineages. We show that the rates of macro- and microrearrangements of gene order are correlated within individual lineages but are highly variable across different lineages. The most unstable genomes correspond to the pathogenic yeasts Candida albicans and Candida glabrata. Chromosomal maps have been intensively shuffled by numerous interchromosomal rearrangements, even between species that have retained a very high physical fraction of their genomes within small synteny blocks. Despite this intensive reshuffling of gene positions, essential genes, which cluster in low recombination regions in the genome of Saccharomyces cerevisiae, tend to remain syntenic during evolution. This work reveals that the high plasticity of eukaryotic genomes results from rearrangement rates that vary between lineages but also at different evolutionary times of a given lineage.

  20. Precise muon drift tube detectors for high background rate conditions

    Energy Technology Data Exchange (ETDEWEB)

    Engl, Albert

    2011-08-04

    The muon spectrometer of the ATLAS-experiment at the Large Hadron Collider consists of drift tube chambers, which provide the precise measurement of trajectories of traversing muons. In order to determine the momentum of the muons with high precision, the measurement of the position of the muon in a single tube has to be more accurate than {sigma}{<=}100 {mu}m. The large cross section of proton-proton-collisions and the high luminosity of the accelerator cause relevant background of neutrons and {gamma}s in the muon spectrometer. During the next decade a luminosity upgrade to 5.10{sup 34} cm{sup -2}s{sup -1} is planned, which will increase the background counting rates considerably. In this context this work deals with the further development of the existing drift chamber technology to provide the required accuracy of the position measurement under high background conditions. Two approaches of improving the drift tube chambers are described: - In regions of moderate background rates a faster and more linear drift gas can provide precise position measurement without changing the existing hardware. - At very high background rates drift tube chambers consisting of tubes with a diameter of 15 mm are a valuable candidate to substitute the CSC muon chambers. The single tube resolution of the gas mixture Ar:CO{sub 2}:N{sub 2} in the ratio of 96:3:1 Vol %, which is more linear and faster as the currently used drift gas Ar:CO{sub 2} in the ratio of 97:3 Vol %, was determined at the Cosmic Ray Measurement Facility at Garching and at high {gamma}-background counting rates at the Gamma Irradiation Facility at CERN. The alternative gas mixture shows similar resolution without background. At high background counting rates it shows better resolution as the standard gas. To analyse the data the various parts of the setup have to be aligned precisely to each other. The change to an alternative gas mixture allows the use of the existing hardware. The second approach are drift tubes

  1. Coal conversion rate in 1t/d PSU liquefaction reactor; 1t/d PSU ekika hannoto ni okeru sekitan tenka sokudo no kento

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, K.; Imada, K. [Nippon Steel Corp., Tokyo (Japan); Nogami, Y.; Inokuchi, K. [Mitsui SRC Development Co. Ltd., Tokyo (Japan)

    1996-10-28

    To investigate the coal liquefaction characteristics, coal slurry samples were taken from the outlets of the reactors and slurry preheater of NEDOL process 1 t/d process supporting unit (PSU), and were analyzed. Tanito Harum coal was used for liquefaction, and the slurry was prepared with recycle solvent. Liquefaction was performed using synthetic iron sulfide catalyst at reaction temperatures, 450 and 465{degree}C. Solubility of various solid samples was examined against n-hexane, toluene, and tetrahydrofuran (THF). When considering the decrease of IMO (THF-insoluble and ash) as a characteristic of coal conversion reaction, around 20% at the outlet of the slurry preheater, around 70% within the first reactor, and several percents within the successive second and third reactors were converted against supplied coal. Increase of reaction temperature led to the increase of evaporation of oil fraction, which resulted in the decrease of actual slurry flow rate and in the increase of residence time. Thus, the conversion of coal was accelerated by the synergetic effect of temperature and time. Reaction rate constant of the coal liquefaction was around 2{times}10{sup -1} [min{sup -1}], which increased slightly with increasing the reaction temperature from 450 to 465{degree}C. 3 refs., 5 figs., 1 tab.

  2. Iodine laser of high efficiency and fast repetition rate

    Energy Technology Data Exchange (ETDEWEB)

    Hohla, K; Witte, K J

    1976-07-01

    The scaling laws of an iodine laser of high efficiency and fast repetition rate are reported. The laser is pumped with a new kind of low pressure Hg-UV-lamps which convert 32% of the electrical input in UV-light in the absorption band of the iodine laser and which can be fired up to 100 Hz. Details of a 10 kJ/1 nsec system as dimensions, energy density, repetition rate, flow velocity, gas composition and gas pressure and the overall efficiency are given which is expected to be about 2%.

  3. Study of magnetorheological fluids at high shear rates

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiaojie; Gordaninejad, Faramarz [University of Nevada, Department of Mechanical Engineering, Reno, NV (United States)

    2006-08-15

    The tunable rheological properties of magnetorheological (MR) materials at high shear rates are studied using a piston-driven flow-mode-type rheometer. The proposed method provides measurement of the apparent viscosity and yield stress of MR fluids for a shear rate range of 50 to 40,000 s{sup -1}. The rheological properties of a commercial MR fluid, as well as a newly developed MR polymeric gel, and a ferrofluid-based MR fluid are investigated. The results for apparent viscosity and dynamic and static shear stresses under different applied magnetic fields are reported. (orig.)

  4. Palaeohistological Evidence for Ancestral High Metabolic Rate in Archosaurs.

    Science.gov (United States)

    Legendre, Lucas J; Guénard, Guillaume; Botha-Brink, Jennifer; Cubo, Jorge

    2016-11-01

    Metabolic heat production in archosaurs has played an important role in their evolutionary radiation during the Mesozoic, and their ancestral metabolic condition has long been a matter of debate in systematics and palaeontology. The study of fossil bone histology provides crucial information on bone growth rate, which has been used to indirectly investigate the evolution of thermometabolism in archosaurs. However, no quantitative estimation of metabolic rate has ever been performed on fossils using bone histological features. Moreover, to date, no inference model has included phylogenetic information in the form of predictive variables. Here we performed statistical predictive modeling using the new method of phylogenetic eigenvector maps on a set of bone histological features for a sample of extant and extinct vertebrates, to estimate metabolic rates of fossil archosauromorphs. This modeling procedure serves as a case study for eigenvector-based predictive modeling in a phylogenetic context, as well as an investigation of the poorly known evolutionary patterns of metabolic rate in archosaurs. Our results show that Mesozoic theropod dinosaurs exhibit metabolic rates very close to those found in modern birds, that archosaurs share a higher ancestral metabolic rate than that of extant ectotherms, and that this derived high metabolic rate was acquired at a much more inclusive level of the phylogenetic tree, among non-archosaurian archosauromorphs. These results also highlight the difficulties of assigning a given heat production strategy (i.e., endothermy, ectothermy) to an estimated metabolic rate value, and confirm findings of previous studies that the definition of the endotherm/ectotherm dichotomy may be ambiguous. © The Author(s) 2016. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  5. High Data Rate Optical Wireless Communications Based on Ultraviolet Band

    KAUST Repository

    Sun, Xiaobin

    2017-10-01

    Optical wireless communication systems based on ultraviolet (UV)-band has a lot inherent advantages, such as low background solar radiation, low device dark noise. Besides, it also has small restrictive requirements for PAT (pointing, acquisition, and tracking) because of its high atmospheric scattering with molecules and aerosols. And these advantages are driving people to explore and utilize UV band for constructing and implementing a high-data-rate, less PAT communication links, such as diffuse-line-of-sight links (diffuse-LOS) and non-line-of-sight (NLOS). The responsivity of the photodetector at UV range is far lower than that of visible range, high power UV transmitters which can be easily modulated are under investigation. These factors make it is hard to realize a high-data-rate diffuse-LOS or NLOS UV communication links. To achieve a UV link mentioned above with current devices and modulation schemes, this thesis presents some efficient modulation schemes and available devices for the time being. Besides, a demonstration of ultraviolet-B (UVB) communication link is implemented utilizing quadrature amplitude modulation (QAM) orthogonal frequency-division multiplexing (OFDM). The demonstration is based on a 294-nm UVB-light-emitting-diode (UVB-LED) with a full-width at half-maximum (FWHM) of 9 nm, and according to the measured L-I-V curve, we set the bias voltage as 7V for maximum the ac amplitude and thus get a high signal-noise-ratio (SNR) channel, and the light output power is 190 μW with such bias voltage. Besides, there is a unique silica gel lens on top of the LED to concentrate the beam. A -3-dB bandwidth of 29 MHz was measured and a high-speed near-solar-blind communication link with a data rate of 71 Mbit/s was achieved using 8-QAM-OFDM at perfect alignment, and 23.6 Mbit/s using 2-QAM-OFDM when the angle subtended by the pointing direction of the UVB-LED and photodetector (PD) is 12 degrees, thus establishing a diffuse-line-of-sight (LOS) link

  6. Modelling Chemical Kinetics of Soybean Oil Transesterification Process for Biodiesel Production: An Analysis of Molar Ratio between Alcohol and Soybean Oil Temperature Changes on the Process Conversion Rate

    Directory of Open Access Journals (Sweden)

    Maicon Tait

    2006-12-01

    Full Text Available A mathematical model describing chemical kinetics of transesterification of soybean oil for biodiesel production has been developed. The model is based on the reverse mechanism of transesterification reactions and describes dynamics concentration changes of triglycerides, diglycerides, monoglycerides, biodiesel, and glycerol production. Reaction rate constants were written in the Arrhenius form. An analysis of key process variables such as temperature and molar ratio soybean oil- alcohol using response surface analysis was performed to achieve the maximum soybean conversion rate to biodiesel. The predictive power of the developed model was checked for the very wide range of operational conditions and parameters values by fitting different experimental results for homogeneous catalytic and non-catalytic processes published in the literature. A very good correlation between model simulations and experimental data was observed.

  7. High-Rate Performance of Muon Drift Tube Detectors

    CERN Document Server

    Schwegler, Philipp

    The Large Hadron Collider (LHC) at the European Centre for Particle Physics, CERN, collides protons with an unprecedentedly high centre-of-mass energy and luminosity. The collision products are recorded and analysed by four big experiments, one of which is the ATLAS detector. In parallel with the first LHC run from 2009 to 2012, which culminated in the discovery of the last missing particle of the Standard Model of particle physics, the Higgs boson, planning of upgrades of the LHC for higher instantaneous luminosities (HL-LHC) is already progressing. The high instantaneous luminosity of the LHC puts high demands on the detectors with respect to radiation hardness and rate capability which are further increased with the luminosity upgrade. In this thesis, the limitations of the Muon Drift Tube (MDT) chambers of the ATLAS Muon Spectrometer at the high background counting rates at the LHC and performance of new small diameter muon drift tube (sMDT) detectors at the even higher background rates at HL-LHC are stud...

  8. Rate and factors influencing the conversion of abstracts presented at the argentinian congress of hypertension meetings to indexed full peer-reviewed publications.

    Science.gov (United States)

    Barochiner, J; Martínez, R; Choi, M; Espeche, W; Micali, R G; Tomat, A

    2018-03-01

    Publication rates vary significantly among different scientific meetings, with many abstracts never being published as peer-reviewed articles. This issue has never been investigated in the Hypertension field in Argentina. Our purpose was to determine the proportion of abstracts presented at the Argentinian Congress of Hypertension meetings that were published as full articles in peer-reviewed indexed journals, the time lag to publication and the factors associated with successful publication. we conducted a PubMed search to identify peer-reviewed publications of abstracts presented at the Argentinian Congress of Hypertension meetings between 2006 and 2015, assessing publication rate along with the time lag to publication. We also extracted information about several abstract characteristics and, for those that got published, we recorded the date of publication and journal name with its impact factor and H index. Predictors of publication were analyzed using a multivariable model. a total of 619 abstracts were presented between 2006 and 2015. The rate of conversion to full-text peer-reviewed articles by June 2017 was 28.1% (95%CI 24.7-31.8%), with a median time to publication of 15.7 months (IQR 8-30.9). On multivariable analysis, the independent predictors of publication were basic science category (OR 5 [95%CI 2.3-10.8], p<0.001), oral presentation (OR 2.8 [95%CI 1.6-4.9], p<0.001) and being an award winner for the presentation (OR 3 [95%CI 1.3-6.8], p=0.01). conversion rate to full peer-reviewed articles of abstracts presented at the Argentinian Congress of Hypertension meetings is far from ideal, with potential areas where efforts should be concentrated to improve dissemination of knowledge. Copyright © 2018 SEH-LELHA. Publicado por Elsevier España, S.L.U. All rights reserved.

  9. Thermal Effects on the Body mass, Transpiration rate, Feeding and Food Conversion of the Pillbug Armadillo officinalis (Isopoda, Oniscidea Fed on the Dry Leaf of Punica Granatum

    Directory of Open Access Journals (Sweden)

    Abdelgader K. Youssef

    2004-06-01

    Full Text Available Observations were made on the body mass; transpiration rate; assimilation efficiency; gross and net production efficiencies; feeding, assimilation, conversion and metabolic rates of the pillbug Armadillo officinalis Dumeril acclimatized at 14º  and 21 °C for 15 days and fed on the dry leaf of Punica granatum (Pomegranate.  A brief description is given on the chemical composition of P. granatum leaf.  The difference in body mass increments of A. officinalis between the acclimatized temperatures was not significant (t = 1.09; p>0.05.  However, significant differences were discernible on the transpiration rate (t = 9.53; p<0.01, moisture (t = 9.01; p<0.01, assimilation efficiency (t = 5.16; p<0.01, feeding (t = 3.76; p<0.05 and conversion (t = 2.58; p<0.05  rates between the woodlice acclimatized at 14º and 21 °C.  Better feeding of    P. granatum leaf by these animals was observed at 21° C, but better assimilation efficiency at 14 °C.  Only 3.21% assimilated food at 14° C and 6.30% at 21 °C were converted into the production of new tissues.  The food consumption of A. officinalis at 14º and 21° C was 2.05% and 3.79% body mass/day respectively.  The effect of temperature on the activity of A. officinalis in the field is discussed.

  10. Dynamic High-Temperature Characterization of an Iridium Alloy in Compression at High Strain Rates

    Energy Technology Data Exchange (ETDEWEB)

    Song, Bo [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Experimental Environment Simulation Dept.; Nelson, Kevin [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Mechanics of Materials Dept.; Lipinski, Ronald J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Advanced Nuclear Fuel Cycle Technology Dept.; Bignell, John L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Structural and Thermal Analysis Dept.; Ulrich, G. B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Radioisotope Power Systems Program; George, E. P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Radioisotope Power Systems Program

    2014-06-01

    Iridium alloys have superior strength and ductility at elevated temperatures, making them useful as structural materials for certain high-temperature applications. However, experimental data on their high-temperature high-strain-rate performance are needed for understanding high-speed impacts in severe elevated-temperature environments. Kolsky bars (also called split Hopkinson bars) have been extensively employed for high-strain-rate characterization of materials at room temperature, but it has been challenging to adapt them for the measurement of dynamic properties at high temperatures. Current high-temperature Kolsky compression bar techniques are not capable of obtaining satisfactory high-temperature high-strain-rate stress-strain response of thin iridium specimens investigated in this study. We analyzed the difficulties encountered in high-temperature Kolsky compression bar testing of thin iridium alloy specimens. Appropriate modifications were made to the current high-temperature Kolsky compression bar technique to obtain reliable compressive stress-strain response of an iridium alloy at high strain rates (300 – 10000 s-1) and temperatures (750°C and 1030°C). Uncertainties in such high-temperature high-strain-rate experiments on thin iridium specimens were also analyzed. The compressive stress-strain response of the iridium alloy showed significant sensitivity to strain rate and temperature.

  11. Mechanical characterization of rocks at high strain rate

    Directory of Open Access Journals (Sweden)

    Konstantinov A.

    2012-08-01

    Full Text Available The paper presents the dynamic characterization in tension and compression of three rocks, Carrara marble, Onsernone gneiss and Peccia Marble, at high strain-rates. Two versions of a Split Hopkinson Bar have been used. The version for direct tension tests is installed at the DynaMat Laboratory of the University of Applied Sciences of Southern Switzerland, while the traditional version in compression is installed at the Laboratory of Dynamic Investigation of Materials of Lobachevsky State University. Results of the tests show a significantly strain-rate sensitive behaviour, exhibiting dynamic strength increasing with strain-rate. The experimental research has been developed in the frame of the Swiss-Russian Joint Research Program.

  12. Enhanced energy conversion efficiency from high strength synthetic organic wastewater by sequential dark fermentative hydrogen production and algal lipid accumulation.

    Science.gov (United States)

    Ren, Hong-Yu; Liu, Bing-Feng; Kong, Fanying; Zhao, Lei; Xing, Defeng; Ren, Nan-Qi

    2014-04-01

    A two-stage process of sequential dark fermentative hydrogen production and microalgal cultivation was applied to enhance the energy conversion efficiency from high strength synthetic organic wastewater. Ethanol fermentation bacterium Ethanoligenens harbinense B49 was used as hydrogen producer, and the energy conversion efficiency and chemical oxygen demand (COD) removal efficiency reached 18.6% and 28.3% in dark fermentation. Acetate was the main soluble product in dark fermentative effluent, which was further utilized by microalga Scenedesmus sp. R-16. The final algal biomass concentration reached 1.98gL(-1), and the algal biomass was rich in lipid (40.9%) and low in protein (23.3%) and carbohydrate (11.9%). Compared with single dark fermentation stage, the energy conversion efficiency and COD removal efficiency of two-stage system remarkably increased 101% and 131%, respectively. This research provides a new approach for efficient energy production and wastewater treatment using a two-stage process combining dark fermentation and algal cultivation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Basic policy of maintenance for the power conversion system of the gas turbine high temperature reactor 300 (GTHTR300)

    International Nuclear Information System (INIS)

    Kosugiyama, Shinichi; Takizuka, Takakazu; Kunitomi, Kazuhiko; Yan, Xing; Katanishi, Shoji; Takada, Shoji

    2003-01-01

    Basic policy of maintenance was determined for major equipment in the power conversion system of the Gas Turbine High Temperature Reactor 300 (GTHTR300). It was developed based on the current maintenance practice in Light Water Reactors (LWRs), High Temperature Engineering Test Reactor (HTTR) and conventional combined cycle power plants while taking into account of unique design features of GTHTR300. First, potential degradation phenomena in operations were identified and corresponding maintenance approaches were proposed for the equipment. Such degradations encountered typically in LWRs as corrosion, erosion and stress corrosion cracking are unlikely to occur since the working fluid of GTHTR300 is inert helium. Main causes of the degradations are high operating temperature and pressure. The gas turbine, compressor, generator, control valves undergo opening and dismantling maintenance in a suitable time interval. The power conversion vessel, heat exchanger vessel, primary system piping and heat exchanging tubes of precooler are subjected to in-service inspections similar to those done in LWRs. As turbine blades represent the severest material degradation because of their high-temperature and high-stress operating conditions, a lifetime management scheme was suggested for them. The longest interval of open-casing maintenance of the gas turbine is estimated to be six to seven years from technical point of view. Present study is entrusted from the Ministry of Education, Culture, Sports, Science and Technology of Japan. (author)

  14. High freight rates hinder oil markets' return to equilibrium

    International Nuclear Information System (INIS)

    Anon

    2005-01-01

    Hurricane damage to refineries in the US has created shortages of refined products there, boosting imports and sending freight rates across the Atlantic to record levels. The situation was made worse for a time by a strike at France's main oil terminals in the Mediterranean, which prevented some oil tankers from being rapidly redeployed to routes across the Atlantic. Worldscale (WS) rates for routes from the UK and Europe to the US Atlantic and Gulf Coasts rose well above WS500 for clean tonnage during October. High rates were nevertheless not simply confined to product tankers crossing the Atlantic. Rates for crude tankers to the US have also risen, and tightness has begun to appear in some other markets as well. The net result has been to slow down the movement of oil from regions of surplus to those of scarcity, depressing prices in the former and keeping them at high levels in the latter. Atlantic tanker markets look like remaining tight for the rest of the year and perhaps beyond. (author)

  15. Investigation of high-rate lithium-thionyl chloride cells

    Science.gov (United States)

    Hayes, Catherine A.; Gust, Steven; Farrington, Michael D.; Lockwood, Judith A.; Donaldson, George J.

    Chemical analysis of a commercially produced high-rate D-size lithium-thionyl cell was carried out, as a function of rate of discharge (1 ohm and 5 ohms), depth of discharge, and temperature (25 C and -40 C), using specially developed methods for identifying suspected minor cell products or impurities which may effect cell performance. These methods include a product-retrieval system which involves solvent extraction to enhance the recovery of suspected semivolatile minor chemicals, and methods of quantitative GC analysis of volatile and semivolatile products. The nonvolatile products were analyzed by wet chemical methods. The results of the analyses indicate that the predominant discharge reaction in this cell is 4Li + 2SOCl2 going to 4LiCl + S + SO2, with SO2 formation decreasing towards the end of cell life (7 to 12 Ah). The rate of discharge had no effect on the product distribution. Upon discharge of the high-rate cell at -40 C, one cell exploded, and all others exhibited overheating and rapid internal pressure rise when allowed to warm up to room temperature.

  16. Development of amplifier and shaper for high-rate MWPC

    International Nuclear Information System (INIS)

    Kamiji, Ichinori; Nanjo, Hajime; Kawasaki, Naoki; Maeda, Yosuke; Naito, Daichi; Seki, Shigeto; Nakagiri, Kota; Sasao, Noboru; Nomura, Tadashi

    2015-01-01

    A multi-wire proportional chamber (MWPC) will be used as an in-beam charged particle detector for the J-PARC E14 (KOTO) experiment. The maximum counting rate of the MWPC is expected to be up to 1 MHz per channel due to the high neutron and photon flux, expected to be 1 GHz for the 30 x 30 cm"2 area. An amplifier to cope with such high counting-rate is required. We developed a prototype of such amplifier, which has a charge preamplifier with the integration time of 3 ns and a pulse shaping part with three pole-zero cancellation networks. The shaper reduced the characteristic long tail lasting tens of microseconds in the signal of MWPC to 150 ns. Its performance has been tested by using a single-channel MWPC which has almost the same geometrical parameters as the MWPC to be installed in the KOTO experiment. (author)

  17. Characteristics of Multiplexed Grooved Nozzles for High Flow Rate Electrospray

    International Nuclear Information System (INIS)

    Kim, Kyoung Tae; Kim, Woo Jin; Kim, Sang Soo

    2007-01-01

    The electrospray operated in the cone-jet mode can generate highly charged micro droplets in an almost uniform size at flow rates. Therefore, the multiplexing system which can retain the characteristics of the cone-jet mode is inevitable for the electrospray application. This experiment reports the multiplexed grooved nozzle system with the extractor. The effects of the grooves and the extractor on the performance of the electrospray were evaluated through experiments. Using the grooved nozzle, the stable cone-jet mode can be achieved at the each groove in the grooved mode. Furthermore, the number of nozzles per unit area is increased by the extractor. The multiplexing density is 12 jets per cm 2 at 30 mm distance from the nozzle tip to the ground plate. The multiplexing system for the high flow rate electrospray is realized with the extractor which can diminish the space charge effect without sacrificing characteristics of the cone-jet mode

  18. Assessment of independent risk factors of conversion into psychosis in the ultra-high risk state group of patients

    Directory of Open Access Journals (Sweden)

    Marta Gawłowska

    2010-12-01

    Full Text Available Background: The aim of this study was the independent psychosis risk factors assessment in a group of subjects fulfilling the criteria of at risk mental state, under specialist outpatient psychiatric care. Participants: Seventy-one patients – 33 women and 38 men, were involved into this study, aged on average 17.34, all under psychiatric care. The patients were recruited into the study in the sequence of their outpatient clinic admission. The criterion to be included into the study was the diagnosis of ultra-high risk state (UHRS – defined according to the Australian research group principles. Subsequently, the patients were divided into subgroups according to the clinical features of their mental state. Method: The author’s demographic questionnaire was applied in the study. Information regarding the family history of psychosis was obtained from patients and/or their relatives or carers. The patients’ mental state was assessed monthly – according to the presence of psychotic symptoms, change of their incidence and duration, presence of depressive symptoms or aggressive behaviour (measured by a three-level scale. On the basis of the obtained information, we evaluated: 1 conversion into psychosis time – measured from diagnosing of UHRS to the development of full-symptom psychosis, 2 therapeutic methods used (psychotherapy, pharmacotherapy or both, 3 use of psychoactive substances after being diagnosed with UHRS, 4 presence of serious life stressors (the patients’ subjective estimation – during the six-month period preceding the conversion into psychosis. Results: 1 In the UHRS group of patients, staying under professional outpatient psychiatric care, the use of marijuana was an independent risk factor of conversion into psychosis. 2 In the investigated group of patients with at risk mental state we did not find any correlation between modulating factors (including: therapeutic methods used, depressive symptoms, aggression or

  19. Sustainability Aspects of Energy Conversion in Modern High-Speed Trains with Traction Induction Motors

    Directory of Open Access Journals (Sweden)

    Marc A. Rosen

    2015-03-01

    Full Text Available Some aspects are illustrated of energy conversion processes during the operation of electric railway vehicles with traction induction motors, in order to support transport systems’ sustainability. Increasing efforts are being expended to enhance the sustainability of transportation technologies and systems. Since electric drive systems are used with variable voltage variable frequency (VVVF inverters and traction induction motors, these machines with appropriate controls can realize both traction and electric braking regimes for electric traction vehicles. In line with this idea, this paper addresses the operation sustainability of electric railway vehicles highlighting the chain of interactions among the main electric equipment on an electrically driven railway system supplied from an a.c. contact line: The contact line-side converter, the machine-side converter and the traction induction motor. The paper supports the findings that electric traction drive systems using induction motors fed by network-side converters and VVVF inverters enhance the sustainable operation of railway trains.

  20. High efficiency β radioisotope energy conversion using reciprocating electromechanical converters with integrated betavoltaics

    Science.gov (United States)

    Duggirala, Rajesh; Li, Hui; Lal, Amit

    2008-04-01

    We demonstrate a 5.1% energy conversion efficiency Ni63 radioisotope power generator by integrating silicon betavoltaic converters with radioisotope actuated reciprocating piezoelectric unimorph cantilever converters. The electromechanical energy converter efficiently utilizes both the kinetic energy and the electrical charge of the 0.94μW β radiation from a 9mCi Ni63 thin film source to generate maximum (1) continuous betavoltaic electrical power output of 22nW and (2) pulsed piezoelectric electrical power output of 750μW at 0.07% duty cycle. The electromechanical converters can be potentially used to realize 100year lifetime power sources for powering periodic sampling remote wireless sensor microsystems.

  1. Conversion and Blending Facility highly enriched uranium to low enriched uranium as oxide. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-05

    This Conversion and Blending Facility (CBF) will have two missions: (1) convert HEU materials into pure HEU oxide and (2) blend the pure HEU oxide with depleted and natural uranium oxide to produce an LWR grade LEU product. The primary emphasis of this blending operation will be to destroy the weapons capability of large, surplus stockpiles of HEU. The blended LEU product can only be made weapons capable again by the uranium enrichment process. To the extent practical, the chemical and isotopic concentrations of blended LEU product will be held within the specifications required for LWR fuel. Such blended LEU product will be offered to the United States Enrichment Corporation (USEC) to be sold as feed material to the commercial nuclear industry. Otherwise, blended LEU will be produced as a waste suitable for storage or disposal.

  2. Conversion and Blending Facility Highly enriched uranium to low enriched uranium as uranium hexafluoride. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-07-05

    This report describes the Conversion and Blending Facility (CBF) which will have two missions: (1) convert surplus HEU materials to pure HEU UF{sub 6} and a (2) blend the pure HEU UF{sub 6} with diluent UF{sub 6} to produce LWR grade LEU-UF{sub 6}. The primary emphasis of this blending be to destroy the weapons capability of large, surplus stockpiles of HEU. The blended LEU product can only be made weapons capable again by the uranium enrichment process. The chemical and isotopic concentrations of the blended LEU product will be held within the specifications required for LWR fuel. The blended LEU product will be offered to the United States Enrichment Corporation (USEC) to be sold as feed material to the commercial nuclear industry.

  3. Evaluation of a microwave high-power reception-conversion array for wireless power transmission

    Science.gov (United States)

    Dickinson, R. M.

    1975-01-01

    Initial performance tests of a 24-sq m area array of rectenna elements are presented. The array is used as the receiving portion of a wireless microwave power transmission engineering verification test system. The transmitting antenna was located at a range of 1.54 km. Output dc voltage and power, input RF power, efficiency, and operating temperatures were obtained for a variety of dc load and RF incident power levels at 2388 MHz. Incident peak RF intensities of up to 170 mW/sq cm yielded up to 30.4 kW of dc output power. The highest derived collection-conversion efficiency of the array was greater than 80 percent.

  4. Conversion and Blending Facility Highly enriched uranium to low enriched uranium as uranium hexafluoride. Revision 1

    International Nuclear Information System (INIS)

    1995-01-01

    This report describes the Conversion and Blending Facility (CBF) which will have two missions: (1) convert surplus HEU materials to pure HEU UF 6 and a (2) blend the pure HEU UF 6 with diluent UF 6 to produce LWR grade LEU-UF 6 . The primary emphasis of this blending be to destroy the weapons capability of large, surplus stockpiles of HEU. The blended LEU product can only be made weapons capable again by the uranium enrichment process. The chemical and isotopic concentrations of the blended LEU product will be held within the specifications required for LWR fuel. The blended LEU product will be offered to the United States Enrichment Corporation (USEC) to be sold as feed material to the commercial nuclear industry

  5. Energy Conversion Mechanism for Electron Perpendicular Energy in High Guide-Field Reconnection

    Science.gov (United States)

    Guo, Xuehan; Horiuchi, Ritoku; Kaminou, Yasuhiro; Cheng, Frank; Ono, Yasushi

    2016-10-01

    The energy conversion mechanism for electron perpendicular energy, both the thermal and the kinetic energy, is investigated by means of two-dimensional, full-particle simulations in an open system. It is shown that electron perpendicular heating is mainly due to the breaking of magnetic moment conservation in separatrix region because the charge separation generates intense variation of electric field within the electron Larmor radius. Meanwhile, electron perpendicular acceleration takes place manly due to the polarization drift term as well as the curvature drift term of E . u⊥ in the downstream near the X-point. The enhanced electric field due to the charge separation there results in a significant effect of the polarization drift term on the dissipation of magnetic energy within the ion inertia length in the downstream. Japan Society for the Promotion of Science (JSPS) Fellows 15J03758.

  6. Miniaturized Stretchable and High-Rate Linear Supercapacitors

    OpenAIRE

    Zhu, Wenjun; Zhang, Yang; Zhou, Xiaoshuang; Xu, Jiang; Liu, Zunfeng; Yuan, Ningyi; Ding, Jianning

    2017-01-01

    Linear stretchable supercapacitors have attracted much attention because they are well suited to applications in the rapidly expanding field of wearable electronics. However, poor conductivity of the electrode material, which limits the transfer of electrons in the axial direction of the linear supercapacitors, leads to a serious loss of capacity at high rates. To solve this problem, we use gold nanoparticles to decorate aligned multiwall carbon nanotube to fabricate stretchable linear electr...

  7. High repetition rate burst-mode spark gap

    International Nuclear Information System (INIS)

    Faltens, A.; Reginato, L.; Hester, R.; Chesterman, A.; Cook, E.; Yokota, T.; Dexter, W.

    1978-01-01

    Results are presented on the design and testing of a pressurized gas blown spark gap switch capable of high repetition rates in a burst mode of operation. The switch parameters which have been achieved are as follows: 220-kV, 42-kA, a five pulse burst at 1-kHz, 12-ns risetime, 2-ns jitter at a pulse width of 50-ns

  8. High rate multiplicity detector for relativistic heavy-ion collisions

    International Nuclear Information System (INIS)

    Beavis, D.; Bennett, M.J.; Carroll, J.B.; Chiba, J.; Chikanian, A.; Crawford, H.J.; Cronqvist, M.; Dardenne, Y.; Debbe, R.; Doke, T.; Engelage, J.; Flores, I.; Greiner, L.; Hayano, R.S.; Hallman, T.J.; Heckman, H.H.; Kashiwagi, T.; Kikuchi, J.; Kumar, B.S.; Kuo, C.; Lindstrom, P.J.; Mitchell, J.W.; Nagamiya, S.; Nagle, J.L.; Pope, J.K.; Stankus, P.; Tanaka, K.H.; Welsh, R.C.; Zhan, W.

    1995-01-01

    We have constructed and operated a detector to measure the multiplicity of secondary particles produced in nucleus-nucleus collisions in the E878 experiment at the Brookhaven National Laboratory AGS facility. We describe the operation and performance of the detector in a high rate Au beam environment, and interpret the multiplicity data in terms of the impact parameters of the nucleus-nucleus collisions. ((orig.))

  9. High rate multiplicity detector for relativistic heavy-ion collisions

    Energy Technology Data Exchange (ETDEWEB)

    Beavis, D [Brookhaven National Lab., Upton, NY (United States); Bennett, M J [Yale University, A.W. Wright Nuclear Structure Laboratory, New Haven, CT 06511 (United States); Carroll, J B [University of California at Los Angeles, Los Angeles, CA (United States); Chiba, J [KEK National High Energy Physics, Tsukuba (Japan); Chikanian, A [Yale University, A.W. Wright Nuclear Structure Laboratory, New Haven, CT 06511 (United States); Crawford, H J [University of California Space Sciences Laboratory, Berkeley, CA (United States); Cronqvist, M [University of California Space Sciences Laboratory, Berkeley, CA (United States); Dardenne, Y [University of California Space Sciences Laboratory, Berkeley, CA (United States); Debbe, R [Brookhaven National Lab., Upton, NY (United States); Doke, T [Waseda University, Science and Engineering Research Institute, Waseda (Japan); Engelage, J [University of California Space Sciences Laboratory, Berkeley, CA (United States); Flores, I [University of California Space Sciences Laboratory, Berkeley, CA (United States); Greiner, L [University of California Space Sciences Laboratory, Berkeley, CA (United States); Hayano, R S [University of Tokyo, Tokyo (Japan); Hallman, T J [University of California at Los Angeles, Los Angeles, CA (United States); Heckman, H H [Lawrence Berkeley Lab., CA (United States); Kashiwagi, T [Waseda University, Science and Engineering Research Institute, Waseda (Japan); Kikuchi, J [Waseda University, Science and Engineering Research Institute, Waseda (Japan); Kumar, B S [Yale University, A.W. Wright Nuclear Structure Laboratory, New Haven, CT 06511 (United States); Kuo, C [University of California Space Sciences Laboratory, Berkeley, CA (United States); Lindstrom, P J [Lawrence Berkeley Lab., CA (United States); Mitchell, J W [Universities Space Research Association/Goddard Space Flight Center, Greenbelt, MD (United States); Nagamiya, S; E878 Collaboration

    1995-04-21

    We have constructed and operated a detector to measure the multiplicity of secondary particles produced in nucleus-nucleus collisions in the E878 experiment at the Brookhaven National Laboratory AGS facility. We describe the operation and performance of the detector in a high rate Au beam environment, and interpret the multiplicity data in terms of the impact parameters of the nucleus-nucleus collisions. ((orig.)).

  10. MDT Performance in a High Rate Background Environment

    CERN Document Server

    Aleksa, Martin; Hessey, N P; Riegler, W

    1998-01-01

    A Cs137 gamma source with different lead filters in the SPS beam-line X5 has been used to simulate the ATLAS background radiation. This note shows the impact of high background rates on the MDT efficiency and resolution for three kinds of pulse shaping and compares the results with GARFIELD simulations. Furthermore it explains how the performance can be improved by time slewing corrections and double track separation.

  11. Enzymatic hydrolysis at high-solids loadings for the conversion of agave bagasse to fuel ethanol

    International Nuclear Information System (INIS)

    Caspeta, Luis; Caro-Bermúdez, Mario A.; Ponce-Noyola, Teresa; Martinez, Alfredo

    2014-01-01

    Highlights: • Conversion of agave bagasse to fuel ethanol. • Ethanosolv-pretreatment variables were statistically adjusted. • 91% of total sugars found in agave bagasse were recovered. • 225 g/L glucose from 30%-consistency hydrolysis using mini-reactors with peg-mixers. • 0.25 g of ethanol per g of dry agave bagasse was obtained. - Abstract: Agave bagasse is the lignocellulosic residue accumulated during the production of alcoholic beverages in Mexico and is a potential feedstock for the production of biofuels. A factorial design was used to investigate the effect of temperature, residence time and concentrations of acid and ethanol on ethanosolv pretreatment and enzymatic hydrolysis of agave bagasse. This method and the use of a stirred in-house-made mini-reactor increased the digestibility of agave bagasse from 30% observed with the dilute-acid method to 98%; also allowed reducing the quantity of enzymes used to hydrolyze samples with solid loadings of 30% w/w and glucose concentrations up to 225 g/L were obtained in the enzymatic hydrolysates. Overall this process allows the recovery of 91% of the total fermentable sugars contained in the agave bagasse (0.51 g/g) and 69% of total lignin as co-product (0.11 g/g). The maximum ethanol yield under optimal conditions using an industrial yeast strain for the fermentation was 0.25 g/g of dry agave bagasse, which is 86% of the maximum theoretical (0.29 g/g). The effect of the glucose concentration and solid loading on the conversion of cellulose to glucose is discussed, in addition to prospective production of about 50 million liters of fuel ethanol using agave bagasse residues from the tequila industry as a potential solution to the disposal problems

  12. Conversion of highly enriched uranium in thorium-232 based oxide fuel for light water reactors: MOX-T fuel

    Energy Technology Data Exchange (ETDEWEB)

    Vapirev, E I; Jordanov, T; Christoskov, I [Sofia Univ. (Bulgaria). Fizicheski Fakultet

    1994-12-31

    The idea of conversion of highly enriched uranium (HEU) from warheads without mixing it with natural uranium as well as the utilization of plutonium as fuel component is discussed. A nuclear fuel which is a mixture of 4% {sup 235}U (HEU) as a fissile isotope and 96 % {sup 232}Th (ThO{sub 2}) as a non-fissile isotope in a mixed oxide with thorium fuel is proposed. It is assumed that plutonium can also be used in the proposed fuel in a mixture with {sup 235}U. The following advantages of the use of HEU in LWRs in mixed {sup 235}U - Th fuel are pointed out: (1) No generation of long-living plutonium and americium isotopes (in case of reprocessing the high level radioactive wastes will contain only fission fragments and uranium); (2) The high conversion ratio of Th extends the expected burnup by approximately 1/3 without higher initial enrichment (the same initial enrichment simplifies the problem for compensation of the excess reactivity in the beginning with burnable poison and boric acid); (3) The high conversion ratio of Th allows the fuel utilization with less initial enrichment (by approx. 1/3) for the same burnup; thus less excess reactivity has to be compensated after reloading; in case of fuel reprocessing all fissile materials ({sup 235}U + {sup 233}U) could be chemically extracted. Irrespectively to the optimistic expectations outlined, further work including data on optimal loading and reloading schemes, theoretical calculations of thermal properties of {sup 235}U + Th fuel rods, manufacturing of several test fuel assemblies and investigations of their operational behaviour in a reactor core is still needed. 1 fig., 7 refs.

  13. High rate amplifier-digitizer system for liquid argon calorimeters

    International Nuclear Information System (INIS)

    Droege, T.F.; Lobkowicz, F.; Fukushima, Y.

    1978-01-01

    A low-cost charge amplifier for a liquid argon photon detector and a new method for pulse height analysis are described. This scheme is suitable for high-energy photon detection with high counting rate. Samples of preamplifer output are taken just before and just after the arrival of the charge from the detector. The difference of these samples provides a stable pedestal and rejects low frequency noise. Short two-pulse resolving time (approximately equal to 200ns) is achieved. 6 refs

  14. Abuse resistant high rate lithium/thionyl chloride cells

    Energy Technology Data Exchange (ETDEWEB)

    Surprenant, J.; Snuggerud, D.

    1982-08-01

    A compact, disc shaped lithium/thionyl chloride cell has been developed by Altus Corporation. The cell has a 6 Amphr capacity and is capable of high rate discharge at high voltage. Discharge data is presented over the range of 0.07 to 1.1 Amperes. The cell is operable over the temperature range of -40/sup 0/C to +70/sup 0/C, and has a 10 year shelf life at 20/sup 0/C. Safety features allow the cells to withstand fire, puncture, shock, spin, forced discharge or forced charge without dangerous reactions.

  15. Abuse resistant high rate lithium/thionyl chloride cells

    Science.gov (United States)

    Surprenant, J.; Snuggerud, D.

    A compact, disk shaped lithium/thionyl chloride cell has been developed. The cell has a 6 Amphr capacity and is capable of high rate discharge at high voltage. Discharge data are presented over the range of 0.07 to 1.1 amperes. The cell is operable over the temperature range of -40 C to +70 C, and has a 10 year shelf life at 20 C. Safety features allow the cells to withstand fire, puncture, shock, spin, forced discharge or forced charge without dangerous reactions.

  16. Semi-solid electrodes having high rate capability

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Yet-Ming; Duduta, Mihai; Holman, Richard; Limthongkul, Pimpa; Tan, Taison

    2017-11-28

    Embodiments described herein relate generally to electrochemical cells having high rate capability, and more particularly to devices, systems and methods of producing high capacity and high rate capability batteries having relatively thick semi-solid electrodes. In some embodiments, an electrochemical cell includes an anode and a semi-solid cathode. The semi-solid cathode includes a suspension of an active material of about 35% to about 75% by volume of an active material and about 0.5% to about 8% by volume of a conductive material in a non-aqueous liquid electrolyte. An ion-permeable membrane is disposed between the anode and the semi-solid cathode. The semi-solid cathode has a thickness of about 250 .mu.m to about 2,000 .mu.m, and the electrochemical cell has an area specific capacity of at least about 7 mAh/cm.sup.2 at a C-rate of C/4. In some embodiments, the semi-solid cathode slurry has a mixing index of at least about 0.9.

  17. THE DISCLOSURE OF THE CONVERSION OF VOLUME AND UTILIZATION OF FIXED CAPITAL IN THE COMMERCIAL RATE OF RETURN

    Directory of Open Access Journals (Sweden)

    CONSTANTIN CĂRUNTU

    2010-01-01

    Full Text Available The efficiency and sustainability in a competitive economy are provided also by the extent to which the company has a material potential whose technical and operational parameters meet the new requirements of market economy. The management of creating value at the enterprise level requires selecting from a range of alternative investments that variant that incubated the most likely probability to increase the value of the firm. The fixed capital of the company is a production factor with a significant role in the performances of economic efficiency of it. The fixed capital incorporates a certain qualitative level of the production tehnologies and its effectiveness will depend decisively on the degree of physical and moral wear and also by the degree to which production capacity is used. At company level, economic efficiency is called return and, if the ratio between effect and effort is expressed as a percentage, is called rate of return. The key element of a company's profitability is the profit which, in its various forms, is taken into account in determining the different rates of return. The objective of any enterprise is to achieve maximum benefit and profitability of capital invested with the view to ensure its development and compensation of those who made capital investments. The profitability is one of the synthetic forms of expressing the efficiency of the entire financial-economic activities of the enterprise, respectively of all the means of production used and labor force, in all stages of economic circuit: supply, production and sales.

  18. Conversion of Low-Flow Priapism to High-Flow State Using T-Shunt with Tunneling.

    Science.gov (United States)

    Mistry, Neil A; Tadros, Nicholas N; Hedges, Jason C

    2017-01-01

    Introduction . The three types of priapism are stuttering, arterial (high-flow, nonischemic), and venoocclusive (low-flow, ischemic). These are usually distinct entities and rarely occur in the same patient. T-shunts and other distal shunts are frequently combined with tunneling, but a seldom recognized potential complication is conversion to a high-flow state. Case Presentation . We describe 2 cases of men who presented with low-flow priapism episodes that were treated using T-shunts with tunneling that resulted with both men having recurrent erections shortly after surgery that were found to be consistent with high-flow states. Case 1 was a 33-year-old male with sickle cell anemia and case 2 was a 24-year-old male with idiopathic thrombocytopenic purpura. In both cases the men were observed over several weeks and both men returned to normal erectile function. Conclusions . Historically, proximal shunts were performed only in cases when distal shunts failed and carry a higher risk of serious complications. T-shunts and other distal shunts combined with tunneling are being used more frequently in place of proximal shunts. These cases illustrate how postoperative erections after T-shunts with tunneling can signify a conversion from low-flow to high-flow states and could potentially be misdiagnosed as an operative failure.

  19. Theoretical studies aiming at the IEA-R1 reactor core conversion from high U-235 enrichment to low U-235 enrichment

    International Nuclear Information System (INIS)

    Frajndlich, R.

    1982-01-01

    The research reactors, of which the fuel elements are of MTR type, functions presently, almost in their majority with high U-235 enrichment. The fear that those fuel elements might generate a considerabLe proliferation of nuclear weapons rendered almost mandatory the conversion of highly enriched fuel elements to a low U-235 enrichment. As the IEA-R1 reactor of IPEN is operating with highly enriched fuel elements a study aiming at this conversion was done. The problems related to the conversion and the results obtained, demonstrated the technical viabilty for its realization. (E.G.) [pt

  20. High Strain Rate and Shock-Induced Deformation in Metals

    Science.gov (United States)

    Ravelo, Ramon

    2012-02-01

    Large-scale non-equilibrium molecular Dynamics (MD) simulations are now commonly used to study material deformation at high strain rates (10^9-10^12 s-1). They can provide detailed information-- such as defect morphology, dislocation densities, and temperature and stress profiles, unavailable or hard to measure experimentally. Computational studies of shock-induced plasticity and melting in fcc and bcc single, mono-crystal metals, exhibit generic characteristics: high elastic limits, large directional anisotropies in the yield stress and pre-melting much below the equilibrium melt temperature for shock wave propagation along specific crystallographic directions. These generic features in the response of single crystals subjected to high strain rates of deformation can be explained from the changes in the energy landscape of the uniaxially compressed crystal lattice. For time scales relevant to dynamic shock loading, the directional-dependence of the yield strength in single crystals is shown to be due to the onset of instabilities in elastic-wave propagation velocities. The elastic-plastic transition threshold can accurately be predicted by a wave-propagation stability analysis. These strain-induced instabilities create incipient defect structures, which can be quite different from the ones, which characterize the long-time, asymptotic state of the compressed solid. With increase compression and strain rate, plastic deformation via extended defects gives way to amorphization associated with the loss in shear rigidity along specific deformation paths. The hot amorphous or (super-cooled liquid) metal re-crystallizes at rates, which depend on the temperature difference between the amorphous solid and the equilibrium melt line. This plastic-amorphous transition threshold can be computed from shear-waves stability analyses. Examples from selected fcc and bcc metals will be presented employing semi-empirical potentials of the embedded atom method (EAM) type as well as