WorldWideScience

Sample records for preliminary cell performance

  1. Cell emulation and preliminary results.

    Science.gov (United States)

    2016-07-01

    This report details preliminary results of the testing plan implemented by the Hawaii Natural Energy Institute to evaluate Electric Vehicle (EV) battery durability and reliability under electric utility grid operations. Commercial EV battery cells ar...

  2. Preliminary melter performance assessment report

    International Nuclear Information System (INIS)

    Elliott, M.L.; Eyler, L.L.; Mahoney, L.A.; Cooper, M.F.; Whitney, L.D.; Shafer, P.J.

    1994-08-01

    The Melter Performance Assessment activity, a component of the Pacific Northwest Laboratory's (PNL) Vitrification Technology Development (PVTD) effort, was designed to determine the impact of noble metals on the operational life of the reference Hanford Waste Vitrification Plant (HWVP) melter. The melter performance assessment consisted of several activities, including a literature review of all work done with noble metals in glass, gradient furnace testing to study the behavior of noble metals during the melting process, research-scale and engineering-scale melter testing to evaluate effects of noble metals on melter operation, and computer modeling that used the experimental data to predict effects of noble metals on the full-scale melter. Feed used in these tests simulated neutralized current acid waste (NCAW) feed. This report summarizes the results of the melter performance assessment and predicts the lifetime of the HWVP melter. It should be noted that this work was conducted before the recent Tri-Party Agreement changes, so the reference melter referred to here is the Defense Waste Processing Facility (DWPF) melter design

  3. Safety performance of preliminary KALIMER conceptual design

    Energy Technology Data Exchange (ETDEWEB)

    Hahn Dohee; Kim Kyoungdoo; Kwon Youngmin; Chang Wonpyo; Suk Soodong [Korea atomic Energy Resarch Inst., Taejon (Korea)

    1999-07-01

    The Korea Atomic Energy Research Institute (KAERI) is developing KALIMER (Korea Advanced Liquid Metal Reactor), which is a sodium cooled, 150 MWe pool-type reactor. The safety design of KALIMER emphasizes accident prevention by using passive processes, which can be accomplished by the safety design objectives including the utilization of inherent safety features. In order to assess the effectiveness of the inherent safety features in achieving the safety design objectives, a preliminary evaluation of ATWS performance for the KALIMER design has been performed with SSC-K code, which is a modified version of SSC-L code. KAERI's modification of the code includes development of reactivity feedback models for the core and a pool model for KALIMER reactor vessel. This paper describes the models for control rod driveline expansion, gas expansion module and the thermal hydraulic model for reactor pool and the results of preliminary analyses for unprotected loss of flow and loss o heat sink. (author)

  4. Safety performance of preliminary KALIMER conceptual design

    International Nuclear Information System (INIS)

    Hahn Dohee; Kim Kyoungdoo; Kwon Youngmin; Chang Wonpyo; Suk Soodong

    1999-01-01

    The Korea Atomic Energy Research Institute (KAERI) is developing KALIMER (Korea Advanced Liquid Metal Reactor), which is a sodium cooled, 150 MWe pool-type reactor. The safety design of KALIMER emphasizes accident prevention by using passive processes, which can be accomplished by the safety design objectives including the utilization of inherent safety features. In order to assess the effectiveness of the inherent safety features in achieving the safety design objectives, a preliminary evaluation of ATWS performance for the KALIMER design has been performed with SSC-K code, which is a modified version of SSC-L code. KAERI's modification of the code includes development of reactivity feedback models for the core and a pool model for KALIMER reactor vessel. This paper describes the models for control rod driveline expansion, gas expansion module and the thermal hydraulic model for reactor pool and the results of preliminary analyses for unprotected loss of flow and loss o heat sink. (author)

  5. Guidance for performing preliminary assessments under CERCLA

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1991-09-01

    EPA headquarters and a national site assessment workgroup produced this guidance for Regional, State, and contractor staff who manage or perform preliminary assessments (PAs). EPA has focused this guidance on the types of sites and site conditions most commonly encountered. The PA approach described in this guidance is generally applicable to a wide variety of sites. However, because of the variability among sites, the amount of information available, and the level of investigative effort required, it is not possible to provide guidance that is equally applicable to all sites. PA investigators should recognize this and be aware that variation from this guidance may be necessary for some sites, particularly for PAs performed at Federal facilities, PAs conducted under EPA`s Environmental Priorities Initiative (EPI), and PAs at sites that have previously been extensively investigated by EPA or others. The purpose of this guidance is to provide instructions for conducting a PA and reporting results. This guidance discusses the information required to evaluate a site and how to obtain it, how to score a site, and reporting requirements. This document also provides guidelines and instruction on PA evaluation, scoring, and the use of standard PA scoresheets. The overall goal of this guidance is to assist PA investigators in conducting high-quality assessments that result in correct site screening or further action recommendations on a nationally consistent basis.

  6. Preliminary results of testing bioassay analytical performance standards

    International Nuclear Information System (INIS)

    Fisher, D.R.; Robinson, A.V.; Hadley, R.T.

    1983-08-01

    The analytical performance of both in vivo and in vitro bioassay laboratories is being studied to determine the capability of these laboratories to meet the minimum criteria for accuracy and precision specified in the draft ANSI Standard N13.30, Performance Criteria for Radiobioassay. This paper presents preliminary results of the first round of testing

  7. Preliminary performance of the LBL AECR

    International Nuclear Information System (INIS)

    Lyneis, C.M.; Xie, Zuqi; Clark, D.J.; Lam, R.S.; Lundgren, S.A.

    1990-11-01

    The AECR source, which operates at 14 GHz, is being developed for the 88-Inch Cyclotron at Lawrence Berkeley Laboratory. The AECR has been under source development since December 1989, when the mechanical construction was completed. The first AECR beams were injected into the cyclotron in June of 1990 and since then a variety of ion species from the AECR have been accelerated. The cyclotron recently accelerated 209 Bi 38+ to 954 MeV. An electron gun, which injects 10 to 150 eV electrons into the plasma chamber of the AECR, has been developed to increase the production of high charge state ions. With the electron gun the AECR has produced at 10 kV extraction voltage 131 eμA of O 7+ , 13 eμA of O 8+ , 17 eμA of Ar 14+ , 2.2 eμA of Kr 25+ , 1 eμA of Xe 31+ , and 0.2 eμA of Bi 38+ . The AECR was also tested as a single stage source with a coating of SiO 2 on the plasma chamber walls. This significantly improved its performance compared to no coating, but direct injection of electrons with the electron gun produced the best results. 5 refs., 6 figs., 4 tabs

  8. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus: Preliminary Evaluation Results

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, K.; Eudy, L.

    2008-10-01

    This report provides preliminary results from a National Renewable Energy Laboratory evaluation of a protoptye fuel cell transit bus operating at Connecticut Transit in Hartford. Included are descriptions of the planned fuel cell bus demonstration and equipment; early results and agency experience are also provided.

  9. Preliminary test conditions for KNGR SBLOCA DVI ECCS performance test

    International Nuclear Information System (INIS)

    Bae, Kyoo Whan; Song, Jin Ho; Chung, Young Jong; Sim, Suk Ku; Park, Jong Kyun

    1999-03-01

    The Korean Next Generation Reactor (KNGR) adopts 4-train Direct Vessel Injection (DVI) configuration and injects the safety injection water directly into the downcomer through the 8.5'' DVI nozzle. Thus, the thermal hydraulic phenomena such as ECCS mixing and bypass are expected to be different from those observed in the cold leg injection. In order to investigate the realistic injection phenomena and modify the analysis code developed in the basis of cold leg injection, thermal hydraulic test with the performance evaluation is required. Preliminarily, the sequence of events and major thermal hydraulic phenomena during the small break LOCA for KNGR are identified from the analysis results calculated by the CEFLASH-4AS/REM. It is shown from the analysis results that the major transient behaviors including the core mixture level are largely affected by the downcomer modeling. Therefore, to investigate the proper thermal hydraulic phenomena occurring in the downcomer with limited budget and time, the separate effects test focusing on this region is considered to be effective and the conceptual test facility based on this recommended. For this test facility the test initial and boundary conditions are developed using the CEFLASH-4AS/REM analysis results that will be used as input for the preliminary test requirements. The final test requirements will be developed through the further discussions with the test performance group. (Author). 10 refs., 18 tabs., 4 figs

  10. Preliminary study of application of Moringa oleifera resin as polymer electrolyte in DSSC solar cells

    Science.gov (United States)

    Saehana, Sahrul; Darsikin, Muslimin

    2016-04-01

    This study reports the preliminary study of application of Moringa oleifera resin as polymer electrolyte in dye-sensitized solar cell (DSSC). We found that polymer electrolyte membrane was formed by using solution casting methods. It is observed that polymer electrolyte was in elastic form and it is very potential to application as DSSC component. Performance of DSSC which employing Moringa oleifera resin was also observed and photovoltaic effect was found.

  11. Handbook of fuel cell performance

    Energy Technology Data Exchange (ETDEWEB)

    Benjamin, T.G.; Camara, E.H.; Marianowski, L.G.

    1980-05-01

    The intent of this document is to provide a description of fuel cells, their performances and operating conditions, and the relationship between fuel processors and fuel cells. This information will enable fuel cell engineers to know which fuel processing schemes are most compatible with which fuel cells and to predict the performance of a fuel cell integrated with any fuel processor. The data and estimates presented are for the phosphoric acid and molten carbonate fuel cells because they are closer to commercialization than other types of fuel cells. Performance of the cells is shown as a function of operating temperature, pressure, fuel conversion (utilization), and oxidant utilization. The effect of oxidant composition (for example, air versus O/sub 2/) as well as fuel composition is examined because fuels provided by some of the more advanced fuel processing schemes such as coal conversion will contain varying amounts of H/sub 2/, CO, CO/sub 2/, CH/sub 4/, H/sub 2/O, and sulfur and nitrogen compounds. A brief description of fuel cells and their application to industrial, commercial, and residential power generation is given. The electrochemical aspects of fuel cells are reviewed. The phosphoric acid fuel cell is discussed, including how it is affected by operating conditions; and the molten carbonate fuel cell is discussed. The equations developed will help systems engineers to evaluate the application of the phosphoric acid and molten carbonate fuel cells to commercial, utility, and industrial power generation and waste heat utilization. A detailed discussion of fuel cell efficiency, and examples of fuel cell systems are given.

  12. Comments on SKB's SFL 3-5 preliminary performance assessment

    International Nuclear Information System (INIS)

    Wilmot, R.D.; Crawford, M.B.

    2000-01-01

    Recently introduced regulations in Sweden have established an individual risk criterion ( -6 per year) for the long-term performance of repositories for the disposal of radioactive wastes. SKB has not focused its assessment of SFL 3-5 on demonstrating compliance with this regulation. Instead, SKB has calculated individual dose and provided a comparison with an annual individual dose of 14 iSv (derived from the risk criteria using the ICRP's dose-risk conversion factor of 0.073 per Sv). The justification of this approach is that probabilities do not need to be determined if doses are less than the dose equivalent to the risk criterion. However, there is insufficient information regarding uncertainty provided in the documentation of the SFL 3-5 assessment to determine whether this approach is reasonable. SKB's parallel assessment of a repository for spent fuel using the KBS-3 concept (SR 97) accounts for uncertainty by specifying a 'reasonable' and a 'pessimistic' value for uncertain parameters in the assessment calculations. Although there are problems with the way probabilities have been assigned to these values, this approach does indicate where there are significant uncertainties. The SFL 3-5 PA does not include a structured approach to defining uncertainty, although a number of assumptions and parameter values are stated to be conservative. As a preliminary assessment, there is insufficient information to identify key uncertainties or sensitivities, or to determine where further work should be focused. Any assessment requires the use of expert judgement to determine how the assessment is conducted, what modelling approach to use, what features, events and processes (FEPs) could potentially affect the disposal system, which FEPs should be included in the conceptual models, and which scenarios should be assessed. Judgements are also required in determining how to parameterize the models, and this may extend to formal expert elicitation for particular parameter

  13. Deficiencies in school readiness skills of children with sickle cell anemia: a preliminary report.

    Science.gov (United States)

    Chua-Lim, C; Moore, R B; McCleary, G; Shah, A; Mankad, V N

    1993-04-01

    Patients with sickle cell anemia often express myriad clinical signs and symptoms that affect their life-style and academic performance. Certain psychoeducational and psychosocial factors have been shown to influence the academic achievement of older patients with sickle cell anemia. However, studies evaluating the school readiness skills of younger children have not been published. To determine whether sickle cell anemia delays preschool development in children aged 4 to 6 years, we studied 10 affected children and 10 normal subjects matched for age, sex, and race. School readiness was evaluated by the Pediatric Examination of Educational Readiness (PEER), which assess a child's performance in areas of developmental attainment such as visual input, verbal output, and short-term memory. The presence of associated movements (minor neurologic signs) and other areas of behavior such as selective attention, activity level, adaptive behavior, and processing efficiency are also observed. The children with sickle cell anemia scored significantly lower than their normal counterparts in several parameters of the PEER. The McCarthy Scales of Children's Abilities, a standardized psychometric test, showed that these children with sickle cell anemia were within the normal range of intelligence. Magnetic resonance imaging done on three children with sickle cell anemia who scored lowest on the PEER revealed no cerebrovascular infarcts. These preliminary studies demonstrate significant differences in school readiness skills between children with sickle cell anemia and normal subjects.

  14. Preliminary Performance Assessment for Disposal of APT and CLWR/TEF Wastes at SRS

    International Nuclear Information System (INIS)

    Wilhite, E.L.

    1998-01-01

    This section provides the descriptive information for understanding the analyses presented in this preliminary performance assessment. This section addresses the approach taken in the PA, provides a general description of the Savannah River Site E-Area low-level waste facility, and discusses the performance criteria used for evaluating performance

  15. Personality Factors Affecting Pilot Combat Performance: A Preliminary Investigation

    National Research Council Canada - National Science Library

    Siem, Frederick M; Murray, Michael W

    1997-01-01

    .... The present research was designed to examine the relationship between personality and combat performance using the "Big Five" model of personality and a multicomponent model of pilot combat performance...

  16. Preliminary performance assessment for the Waste Isolation Pilot Plant, December 1992

    International Nuclear Information System (INIS)

    1992-01-01

    This volume documents model parameters chosen as of July 1992 that were used by the Performance Assessment Department of Sandia National Laboratories in its 1992 preliminary performance assessment of the Waste Isolation Pilot Plant (WIPP). Ranges and distributions for about 300 modeling parameters in the current secondary data base are presented in tables for the geologic and engineered barriers, global materials (e.g., fluid properties), and agents that act upon the WIPP disposal system such as climate variability and human-intrusion boreholes. The 49 parameters sampled in the 1992 Preliminary Performance Assessment are given special emphasis with tables and graphics that provide insight and sources of data for each parameter

  17. Dynamic Contrast-Enhanced Perfusion Area-Detector CT: Preliminary Comparison of Diagnostic Performance for N Stage Assessment With FDG PET/CT in Non-Small Cell Lung Cancer.

    Science.gov (United States)

    Ohno, Yoshiharu; Fujisawa, Yasuko; Sugihara, Naoki; Kishida, Yuji; Seki, Shinichiro; Koyama, Hisanobu; Yoshikawa, Takeshi

    2017-11-01

    The objective of our study was to directly compare the capability of dynamic first-pass contrast-enhanced (CE) perfusion area-detector CT (ADCT) and FDG PET/CT for differentiation of metastatic from nonmetastatic lymph nodes and assessment of N stage in patients with non-small cell lung carcinoma (NSCLC). Seventy-seven consecutive patients, 45 men (mean age ± SD, 70.4 ± 5.9 years) and 32 women (71.2 ± 7.7 years), underwent dynamic first-pass CE-perfusion ADCT at two or three different positions for covering the entire thorax, FDG PET/CT, surgical treatment, and pathologic examination. From all ADCT data for each of the subjects, a whole-chest perfusion map was computationally generated using the dual- and single-input maximum slope and Patlak plot methods. For quantitative N stage assessment, perfusion parameters and the maximum standardized uptake value (SUV max ) for each lymph node were determined by measuring the relevant ROI. ROC curve analyses were performed for comparing the diagnostic capability of each of the methods on a per-node basis. N stages evaluated by each of the indexes were then statistically compared with the final pathologic diagnosis by means of chi-square and kappa statistics. The area under the ROC curve (A z ) values of systemic arterial perfusion (A z = 0.89), permeability surface (A z = 0.78), and SUV max (A z = 0.85) were significantly larger than the A z values of total perfusion (A z = 0.70, p Dynamic first-pass CE-perfusion ADCT is as useful as FDG PET/CT for the differentiation of metastatic from nonmetastatic lymph nodes and assessment of N stage in patients with NSCLC.

  18. Preliminary Analytical Reviews on the Performance of Fibrous Filter

    International Nuclear Information System (INIS)

    Choi, Yu Jung; Hong, Tae Hyub; Kim, Hyeong-Taek

    2015-01-01

    The wet type Containment Filtered Vent System (CFVS) is composed of a tank including nozzles in a liquid pool, moisture separators, and a few dry filters such as a metal fiber filter and a molecular sieve. After injecting gases from the containment into the CFVS under severe accident conditions, the CFVS will release decontaminated radioactive materials to the environment. To protect against the release of uncontrolled fission products to the environment, we need to confirm the performance of the CFVS in terms of not only the integral capability but also the capabilities of the individual components. It is crucial to confirm the performance of the metal fiber filter in both analytical and experimental ways. Pressure drop across a filter and collection efficiency are ways to explain the performance of a fibrous filter. Based on data from the literature survey, pressure drop and collection efficiency for a single filter were calculated. The trends of pressure drop and collection efficiencies due to various deposition mechanisms of particles onto the fiber of the filters were roughly confirmed. Therefore, to obtain better quantitative predictions of the performance of the metal fiber filter, a new model able to evaluate the performance of fibrous filters under severe conditions should be developed

  19. Preliminary performance and ICF target experiments with Nova

    International Nuclear Information System (INIS)

    Drake, R.P.

    1985-11-01

    In December 1984, the Nova facility fired all ten laser arms, converted the output 1.05 micron energy to 0.35 micron light, and focused the 0.35 micron light through a 4 mm pinhole in the ten-beam target chamber. Since that time, a two-beam target chamber has been added, the performance of the laser evaluated, and preparation has been made for target experiments. This paper summarizes the performance of Nova and describes progress and plans for target experiments

  20. Preliminary analysis on incore performance of nuclear fuel: pt. 4

    International Nuclear Information System (INIS)

    Noh, S.K.; Chang, M.H.; Lee, C.C.; Chung, Y.H.; Kuk, K.Y.; Park, C.Y.; Lee, S.K.

    1981-01-01

    An analysis has been performed for thermal hydraulic design parameters of Wolsung-1 reactor core in steady state with the help of a computer code COBRA-IV-I. The design parameters are coolant enthalpy, flow velocity, coolant quality, pressure and fuel temperature distribution. The maximum power channel has been taken into account in this work. The results appear to be reasonably agreeable with data from PSR'S, with the maximum difference between this work and PSR'S being 4.3%

  1. Advanced stellar compass - Onboard autonomous orbit determination, preliminary performance

    DEFF Research Database (Denmark)

    Betto, Maurizio; Jørgensen, John Leif; Jørgensen, Peter Siegbjørn

    2004-01-01

    and the cost of deep space missions. From past experience, it appears that navigation is the Achilles heel of deep space missions. Performed on ground, this imposes considerable constraints on the entire system and limits operations. This makes it is very expensive to execute, especially when the mission lasts...... be implemented into an ASC without degrading the attitude measurements; and (4) to identify the areas of development and consolidation. The results obtained are very encouraging....

  2. Preliminary evidence that glucose ingestion facilitates prospective memory performance.

    Science.gov (United States)

    Riby, Leigh M; Law, Anna S; McLaughlin, Jennifer; Murray, Jennifer

    2011-05-01

    Previous research has found that the ingestion of glucose boosts task performance in the memory domain (including tasks tapping episodic, semantic, and working memory). The present pilot study tested the hypothesis that glucose ingestion would enhance performance on a test of prospective memory. In a between-subjects design, 56 adults ranging from 17 to 80 years of age performed a computerized prospective memory task and an attention (filler) task after 25 g of glucose or a sweetness-matched placebo. Blood glucose measurements were also taken to assess the impact of individual differences on glucose regulation. After the drink containing glucose, cognitive facilitation was observed on the prospective memory task after excluding subjects with impaired fasting glucose level. Specifically, subjects receiving glucose were 19% more accurate than subjects receiving a placebo, a trend that was marginally nonsignificant, F₁,₄₁ = 3.4, P = .07, but that had a medium effect size, d = 0.58. Subjects receiving glucose were also significantly faster on the prospective memory task, F₁,₃₅ = 4.8, P glucose (indicative of poor glucose regulation) was associated with slower prospective memory responding, F₁,₃₅ = 4.4, P memory and executive functioning can benefit from the increased provision of glucose to the brain. Copyright © 2011 Elsevier Inc. All rights reserved.

  3. Advanced analysis of finger-tapping performance: a preliminary study.

    Science.gov (United States)

    Barut, Cağatay; Kızıltan, Erhan; Gelir, Ethem; Köktürk, Fürüzan

    2013-06-01

    The finger-tapping test is a commonly employed quantitative assessment tool used to measure motor performance in the upper extremities. This task is a complex motion that is affected by external stimuli, mood and health status. The complexity of this task is difficult to explain with a single average intertap-interval value (time difference between successive tappings) which only provides general information and neglects the temporal effects of the aforementioned factors. This study evaluated the time course of average intertap-interval values and the patterns of variation in both the right and left hands of right-handed subjects using a computer-based finger-tapping system. Cross sectional study. Thirty eight male individuals aged between 20 and 28 years (Mean±SD = 22.24±1.65) participated in the study. Participants were asked to perform single-finger-tapping test for 10 seconds of test period. Only the results of right-handed (RH) 35 participants were considered in this study. The test records the time of tapping and saves data as the time difference between successive tappings for further analysis. The average number of tappings and the temporal fluctuation patterns of the intertap-intervals were calculated and compared. The variations in the intertap-interval were evaluated with the best curve fit method. An average tapping speed or tapping rate can reliably be defined for a single-finger tapping test by analysing the graphically presented data of the number of tappings within the test period. However, a different presentation of the same data, namely the intertap-interval values, shows temporal variation as the number of tapping increases. Curve fitting applications indicate that the variation has a biphasic nature. The measures obtained in this study reflect the complex nature of the finger-tapping task and are suggested to provide reliable information regarding hand performance. Moreover, the equation reflects both the variations in and the general

  4. A Preliminary Analysis of LANDSAT-4 Thematic Mapper Radiometric Performance

    Science.gov (United States)

    Justice, C.; Fusco, L.; Mehl, W.

    1985-01-01

    The NASA raw (BT) product, the radiometrically corrected (AT) product, and the radiometrically and geometrically corrected (PT) product of a TM scene were analyzed examine the frequency distribution of the digital data; the statistical correlation between the bands; and the variability between the detectors within a band. The analyses were performed on a series of image subsets from the full scence. Results are presented from one 1024 c 1024 pixel subset of Realfoot Lake, Tennessee which displayed a representative range of ground conditions and cover types occurring within the full frame image. From this cursory examination of one of the first seven channel TM data sets, it would appear that the radiometric performance of the system is most satisfactory and largely meets pre-launch specifications. Problems were noted with Band 5 Detector 3 and Band 2 Detector 4. Differences were observed between forward and reverse scan detector responses both for the BT and AT products. No systematic variations were observed between odd and even detectors.

  5. Preliminary Transportation, Aging and Disposal Canister System Performance Specification

    International Nuclear Information System (INIS)

    C.A Kouts

    2006-01-01

    This document provides specifications for selected system components of the Transportation, Aging and Disposal (TAD) canister-based system. A list of system specified components and ancillary components are included in Section 1.2. The TAD canister, in conjunction with specialized overpacks will accomplish a number of functions in the management and disposal of spent nuclear fuel. Some of these functions will be accomplished at purchaser sites where commercial spent nuclear fuel (CSNF) is stored, and some will be performed within the Office of Civilian Radioactive Waste Management (OCRWM) transportation and disposal system. This document contains only those requirements unique to applications within Department of Energy's (DOE's) system. DOE recognizes that TAD canisters may have to perform similar functions at purchaser sites. Requirements to meet reactor functions, such as on-site dry storage, handling, and loading for transportation, are expected to be similar to commercially available canister-based systems. This document is intended to be referenced in the license application for the Monitored Geologic Repository (MGR). As such, the requirements cited herein are needed for TAD system use in OCRWM's disposal system. This document contains specifications for the TAD canister, transportation overpack and aging overpack. The remaining components and equipment that are unique to the OCRWM system or for similar purchaser applications will be supplied by others

  6. High-performance instruments in neutron arena of JHP. Preliminary version

    International Nuclear Information System (INIS)

    Furusaka, M.; Itoh, S.; Otomo, T.; Arai, M.

    1996-05-01

    This report is a preliminary report of high-performance instruments in neutron arena of JHP (Japan Hadron Project). This report consists of as follows; neutron intensity of neutron arena, development of neutron sources in neutron arena, experimental devices and instrumentation. (J.P.N.)

  7. Immunohistochemical characterisation of the hepatic stem cell niche in feline hepatic lipidosis: a preliminary morphological study.

    Science.gov (United States)

    Valtolina, Chiara; Robben, Joris H; Favier, Robert P; Rothuizen, Jan; Grinwis, Guy Cm; Schotanus, Baukje A; Penning, Louis C

    2018-05-01

    Objectives The aim of this study was to describe the cellular and stromal components of the hepatic progenitor cell niche in feline hepatic lipidosis (FHL). Methods Immunohistochemical staining for the progenitor/bile duct marker (K19), activated Kupffer cells (MAC387), myofibroblasts (alpha-smooth muscle actin [α-SMA]) and the extracellular matrix component laminin were used on seven liver biopsies of cats with FHL and three healthy cats. Double immunofluorescence stainings were performed to investigate co-localisation of different cell types in the hepatic progenitor cell (HPC) niche. Results HPCs, Kupffer cells, myofibroblasts and laminin deposition were observed in the liver samples of FHL, although with variability in the expression and positivity of the different immunostainings between different samples. When compared with the unaffected cats where K19 positivity and minimal α-SMA and laminin positivity were seen mainly in the portal area, in the majority of FHL samples K19 and α-SMA-positive cells and laminin positivity were seen also in the periportal and parenchymatous area. MAC387-positive cells were present throughout the parenchyma. Conclusions and relevance This is a preliminary morphological study to describe the activation and co-localisation of components of the HPC niche in FHL. Although the HPC niche in FHL resembles that described in hepatopathies in dogs and in feline lymphocytic cholangitis, the expression of K19, α-SMA, MAC387 and lamin is more variable in FHL, and a common pattern of activation could not be established. Nevertheless, when HPCs were activated, a spatial association between HPCs and their niche could be demonstrated.

  8. Preliminary design and off-design performance analysis of an Organic Rankine Cycle for geothermal sources

    International Nuclear Information System (INIS)

    Hu, Dongshuai; Li, Saili; Zheng, Ya; Wang, Jiangfeng; Dai, Yiping

    2015-01-01

    Highlights: • A method for preliminary design and performance prediction is established. • Preliminary data of radial inflow turbine and plate heat exchanger are obtained. • Off-design performance curves of critical components are researched. • Performance maps in sliding pressure operation are illustrated. - Abstract: Geothermal fluid of 90 °C and 10 kg/s can be exploited together with oil in Huabei Oilfield of China. Organic Rankine Cycle is regarded as a reasonable method to utilize these geothermal sources. This study conducts a detailed design and off-design performance analysis based on the preliminary design of turbines and heat exchangers. The radial inflow turbine and plate heat exchanger are selected in this paper. Sliding pressure operation is applied in the simulation and three parameters are considered: geothermal fluid mass flow rate, geothermal fluid temperature and condensing pressure. The results indicate that in all considered conditions the designed radial inflow turbine has smooth off-design performance and no choke or supersonic flow are found at the nozzle and rotor exit. The lager geothermal fluid mass flow rate, the higher geothermal fluid temperature and the lower condensing pressure contribute to the increase of cycle efficiency and net power. Performance maps are illustrated to make system meet different load requirements especially when the geothermal fluid temperature and condensing pressure deviate from the design condition. This model can be used to provide basic data for future detailed design, and predict off-design performance in the initial design phase

  9. Connecticut Transit (CTTRANSIT) Fuel Cell Transit Bus Preliminary Evaluation Results

    Science.gov (United States)

    2008-10-16

    This report describes operations at Connecticut Transit (CTTRANSIT) in Hartford for one prototype fuel cell bus and three new diesel buses operating from the same location. The report discusses the planned fuel cell bus demonstration and equipment us...

  10. Preliminary study on zinc-carbon battery performance by using neutron tomography

    International Nuclear Information System (INIS)

    Abdul Aziz Mohamed; Nor Abidin Ashari; Mohd Zaid Abdullah; Junita Mohamad Saleh; Azraf Azman; Megat Harun AlRashid Megat Ahmad; Rafhayudi Jamro

    2008-08-01

    This paper describes on the discharging characteristic of zinc-carbon batteries (dry cells) by using a neutron imaging technique called a monochromatic neutron tomography. Experiment was conducted on the Nuclear Malaysia neutron tomography prototype instrument which based on 1-dimensional position sensitive neutron detector. The instrument is constructed at the small angle neutron scattering (SANS) beam line built at the one of the beam ports of TRIGA MARK II Research reactor, Malaysian Nuclear Agency, Bangi, Selangor. The main aim of this preliminary experiment was to test the instrument capability on a real industrial component. It was also aimed to understand structural and chemical changes of these battery particles after experiencing a discharging process. In this preliminary work, new and used batteries used were the products of Eveready company. (Author)

  11. Preliminary performance test of control rod position indicator for ballscrew type CEDM

    International Nuclear Information System (INIS)

    Yoo, J. Y.; Kim, J. H.; Hu, H.; Lee, J. S.; Kim, J. I.

    2003-01-01

    The reliability and accuracy of the information on control rod position are very important to the reactor safety and the design of the core protection system. A survey on the RSPT(Reed Switch Position Transmitter) type control rod position indication system and its actual implementation in the exiting nuclear power plants in Korea was performed first. The prototype of control rod position indicator having the high performance for the ballscrew type CEDM was developed on the basis of RSPT technology identified through the survey. The characteristics of control rod position indicator was defined and documented through design procedure and preliminary performance test

  12. Thermal plasma treatment of cell-phone waste : preliminary result

    Energy Technology Data Exchange (ETDEWEB)

    Ruj, B. [Central Mechanical Engineering Research Inst., Durgapur (India). Thermal Engineering Group; Chang, J.S.; Li, O.L. [McMaster Univ., Hamilton, ON (Canada). Dept. of Engineering Physics; Pietsch, G. [RWTH Aachen Univ., Aachen (Germany)

    2010-07-01

    The cell phone is an indispensable service facilitator, however, the disposal and recycling of cell phones is a major problem. While the potential life span of a mobile phone, excluding batteries, is over 10 years, most of the users upgrade their phones approximately four times during this period. Cell phone waste is significantly more hazardous than many other municipal wastes as it contains thousands of components made of toxic chemicals and metals like lead, cadmium, chromium, mercury, polyvinyl chlorides (PVC), brominated flame retardants, beryllium, antimony and phthalates. Cell phones also use many expensive rare metals. Since cell phones are made up of plastics, metals, ceramics, and trace other substances, primitive recycling or disposal of cell phone waste to landfills and incinerators creates irreversible environmental damage by polluting water and soil, and contaminating air. In order to minimize releases into the environment and threat to human health, the disposal of cell phones needs to be managed in an environmentally friendly way. This paper discussed a safer method of reducing the generation of syngas and hydrocarbons and metal recovery through the treatment of cell phone wastes by a thermal plasma. The presentation discussed the experiment, with particular reference to sample preparation; experimental set-up; and results four samples with different experimental conditions. It was concluded that the plasma treatment of cell phone waste in reduced condition generates gaseous components such as hydrogen, carbon monoxide, and hydrocarbons which are combustible. Therefore, this system is an energy recovery system that contributes to resource conservation and reduction of climate change gases. 5 refs., 2 tabs., 2 figs.

  13. Site Characterization and Preliminary Performance Assessment Calculation Applied To JAEA-Horonobe URL Site of Japan

    International Nuclear Information System (INIS)

    Lim, Doo Hyun; Hatanaka, Koichiro; Ishii, Eiichi

    2010-01-01

    JAEA-Horonobe Underground Research Laboratory (URL) is designed for research and development on high-level radioactive waste (HLW) repository in sedimentary rock. For a potential HLW repository, understanding and implementing fracturing and faulting system, with data from the site characterization, into the performance assessment is essential because fracture and fault will be the major conductors or barriers for the groundwater flow and radionuclide release. The objectives are i) quantitative derivation of characteristics and correlation of fracturing/faulting system with geologic and geophysics data obtained from the site characterization, and ii) preliminary performance assessment calculation with characterized site information

  14. Site Characterization and Preliminary Performance Assessment Calculation Applied To JAEA-Horonobe URL Site of Japan

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Doo Hyun [NE Union Hill Road, Suite 200, WA 98052 (United States); Hatanaka, Koichiro; Ishii, Eiichi [Japan Atomic Energy Agency, Hokkaido (Japan)

    2010-10-15

    JAEA-Horonobe Underground Research Laboratory (URL) is designed for research and development on high-level radioactive waste (HLW) repository in sedimentary rock. For a potential HLW repository, understanding and implementing fracturing and faulting system, with data from the site characterization, into the performance assessment is essential because fracture and fault will be the major conductors or barriers for the groundwater flow and radionuclide release. The objectives are i) quantitative derivation of characteristics and correlation of fracturing/faulting system with geologic and geophysics data obtained from the site characterization, and ii) preliminary performance assessment calculation with characterized site information

  15. A Preliminary Analysis of Reactor Performance Test (LOEP) for a Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyeonil; Park, Su-Ki [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    The final phase of commissioning is reactor performance test, which is to prove the integrated performance and safety of the research reactor at full power with fuel loaded such as neutron power calibration, Control Absorber Rod/Second Shutdown Rod drop time, InC function test, Criticality, Rod worth, Core heat removal with natural mechanism, and so forth. The last test will be safety-related one to assure the result of the safety analysis of the research reactor is marginal enough to be sure about the nuclear safety by showing the reactor satisfies the acceptance criteria of the safety functions such as for reactivity control, maintenance of auxiliaries, reactor pool water inventory control, core heat removal, and confinement isolation. After all, the fuel integrity will be ensured by verifying there is no meaningful change in the radiation levels. To confirm the performance of safety equipment, loss of normal electric power (LOEP), possibly categorized as Anticipated Operational Occurrence (AOO), is selected as a key experiment to figure out how safe the research reactor is before turning over the research reactor to the owner. This paper presents a preliminary analysis of the reactor performance test (LOEP) for a research reactor. The results showed how different the transient between conservative estimate and best estimate will look. Preliminary analyses have shown all probable thermal-hydraulic transient behavior of importance as to opening of flap valve, minimum critical heat flux ratio, the change of flow direction, and important values of thermal-hydraulic parameters.

  16. Preliminary study to improve the performance of SCWR-M during loss-of-flow accident

    Energy Technology Data Exchange (ETDEWEB)

    Liu, X.J., E-mail: xiaojingliu@sjtu.edu.cn [School of Nuclear Science and Engineering, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240 (China); Sun, C.; Wang, Z.D.; Chai, X.; Xiong, J.B.; Yang, Y.H. [School of Nuclear Science and Engineering, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240 (China); Cheng, X. [Institute of Fusion and Nuclear Technology, Karlsruhe Institute of Technology (KIT), Kaiserstr. 12, 76131 Karlsruhe (Germany)

    2016-10-15

    Highlights: • Validation of the ATHLET-SC code to the safety analysis for SCWR. • Loss of flow accident analysis for SCWR-M is performed. • The passive design parameter is optimized. • The optimized SCWR-M design shows a better safety performance. - Abstract: The SCWR-M is one of the conceptual core designs with mixed neutron spectrum (fast and thermal), which is developed at Shanghai Jiao Tong University. Some preliminary calculations of this new conceptual SCWR indicate the SCWR-M system gets better safety characteristics compared to other single spectrum supercritical water cooled reactors. Loss of flow accident (LOFA) is of particular importance among the abnormal events and accidents for SCWR-M. In order to perform the preliminary study to improve the current SCWR-M safety design, this paper presents the validation results of the ATHLET-SC code and optimization work for safety system design parameters of the ICS, ACC, GDCS based on LOFA analysis. The better performance of the optimized design parameters are demonstrated by comparison with the previous design.

  17. Preliminary development of thermal nuclear cell homogenization code

    International Nuclear Information System (INIS)

    Su'ud, Z.; Shafii, M. A.; Yudha, S. P.; Waris, A.; Rijal, K.

    2012-01-01

    Nuclear fuel cell homogenization for thermal reactors usually include three main parts, i.e., fast energy resonance part which usually adopt narrow resonance approximation to treat the resonance, low (intermediate) energy region in which the resonance can not be treated accurately using NR approximation and therefore we should use intermediate resonance treatment, and thermal energy region (very low) in which the effect of thermal must be treated properly. In n this study the application of the intermediate resonance approximation treatment for low energy nuclear resonance is discussed. The method is iterative based. As a sample the method is applied in U-235 low lying resonance and the result is presented and discussed.

  18. Preliminary Seismic Performance Evaluation of RPS Cabinet in a Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Kwag, Shinyoung; Oh, Jinho; Lee, Jongmin; Kim, Youngki [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-05-15

    This RPS cabinet mainly provides the operators with the physical interface to monitor and handle the RPS. The objective of this paper is to perform seismic analyses and evaluate the preliminary structural integrity and seismic capacity of the RPS cabinet. For this purpose, a 3-D finite element model of the RPS cabinet is developed and its modal analyses are carried out for analyzing the dynamic characteristics. Response time history analyses and related safety evaluation are performed for the RPS cabinet subjected to seismic loads. Finally, the seismic margin and seismic fragility of the RPS cabinet are investigated. The seismic analysis, and preliminary structural integrity and seismic margin of the RPS cabinet under self weight and seismic load have been evaluated. For this purpose, 3-D finite element models of the RPS cabinet were developed. A modal analysis, response time history analysis, and seismic fragility analysis were then performed. From the structural analysis results, the RPS cabinet is below the structural design limit under PGA 0.3g (hor.) and 0.2g (ver.) and structurally withstands until PGA 3g (hor.) and 2g (ver.)

  19. Conceptual Designs for the Performance Improvement of APR1400 SIT and Preliminary Performance Evaluation

    International Nuclear Information System (INIS)

    Chu, In-Cheol; Kwon, Tae-Soon; Song, Chul-Hwa

    2008-01-01

    Some evolutionary type PWRs such as APR1400 and APWR adopt advanced safety injection tank (SIT). The SIT of APR1400 has a fluidic device (FD) which passively controls ECC water injection flow rate into reactor coolant system during refill and reflood phases of LB-LOCA (i.e., a high injection flow rate during the refill phase and a low injection flow rate during the reflood phase). The benefit of the FD is the elimination of the function of low pressure safety injection pump from the safety injection system. The flow controlling performance of the APR1400 FD was evaluated using a prototypical full-scale test facility, called VAPER (Valve Performance Evaluation Rig). Even though the performance of the APR1400 FD satisfied major design and licensing requirements, further improvement of the performance is expected such as the extension of total injection period, the delay of nitrogen gas discharge. Several conceptual designs have been being drawn out in order to improve the performance of the APR1400 SIT. The performance of some designs was evaluated using a small scale SIT test rig. The present paper introduces some of the conceptual designs and shows the performance evaluation experimental results

  20. Experimental advances and preliminary mathematical modeling of the Swiss-roll mixed-reactant direct borohydride fuel cell

    Science.gov (United States)

    Aziznia, Amin; Oloman, Colin W.; Gyenge, Előd L.

    2014-11-01

    The Swiss-roll single-cell mixed reactant (SR-MRFC) borohydride - oxygen fuel cell equipped with Pt/carbon cloth 3D anode and either MnO2 or Ag gas-diffusion cathodes is investigated by a combination of experimental studies and preliminary mathematical modeling of the polarization curve. We investigate the effects of four variables: cathode side metallic mesh fluid distributor, separator type (Nafion 112® vs. Viledon®), cathode catalyst (MnO2 vs. Ag), and the hydrophilic pore volume fraction of the gas-diffusion cathode. Using a two-phase feed of alkaline borohydride solution (1 M NaBH4 - 2 M NaOH) and O2 gas in an SR-MRFC equipped with Pt/C 3D anode, MnO2 gas diffusion cathode, Viledon® porous diaphragm, expanded mesh cathode-side fluid distributor, the maximum superficial power density is 2230 W m-2 at 323 K and 105 kPa(abs). The latter superficial power density is almost 3.5 times higher than our previously reported superficial power density for the same catalyst combinations. Furthermore, with a Pt anode and Ag cathode catalyst combination, a superficial power density of 2500 W m-2 is achieved with superior performance durability compared to the MnO2 cathode. The fuel cell results are substantiated by impedance spectroscopy analysis and preliminary mathematical model predictions based on mixed potential theory.

  1. Preliminary performance assessment for the Waste Isolation Pilot Plant, December 1992

    International Nuclear Information System (INIS)

    1992-12-01

    Before disposing of transuranic radioactive waste in the Waste Isolation Pilot Plant (WIPP), the United States Department of Energy (DOE) must evaluate compliance with applicable long-term regulations of the United States Environmental Protection Agency (EPA). Sandia National Laboratories is conducting iterative performance assessments (PAs) of the WIPP for the DOE to provide interim guidance while preparing for a final compliance evaluation. This volume, Volume 2, contains the technical basis for the 1992 PA. Specifically, it describes the conceptual basis for consequence modeling and the PA methodology, including the selection of scenarios for analysis, the determination of scenario probabilities, and the estimation of scenario consequences using a Monte Carlo technique and a linked system of computational models. Additional information about the 1992 PA is provided in other volumes. Volume I contains an overview of WIPP PA and results of a preliminary comparison with the long-term requirements of the EPA's Environmental Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes (40 CFR 191, Subpart B). Volume 3 contains the reference data base and values for input parameters used in consequence and probability modeling. Volume 4 contains uncertainty and sensitivity analyses related to the preliminary comparison with 40 CFR 191B. Volume 5 contains uncertainty and sensitivity analyses of gas and brine migration for undisturbed performance. Finally, guidance derived from the entire 1992 PA is presented in Volume 6

  2. Do district health systems perform differently because of their managers? Preliminary insights from Indonesia

    Directory of Open Access Journals (Sweden)

    Augustine Asante

    2015-07-01

    Full Text Available District health systems (DHS are central to the global efforts to improve health outcomes but many remain ineffective. In many lowresource settings, despite the generally weak DHS there is evidence that some districts consistently perform well against the odds, and this is often attributed to the calibre of managers leading such districts and their management and leadership (M&L skills. This paper examines the M&L practices of district health managers in high and low performing districts in Indonesia in an attempt to understand whether the differences in the performance of DHS can be explained, at least in part, by the differences in the performance of their health managers. We employed a mixed methods case study design focusing on two purposefully selected districts. Data were collected in 2011 using questionnaires and in-depth interviews. The preliminary results suggest that M&L practices of managers in the high and low performing districts are similar and provide little explanation for the differences in the performance of the two DHS. Contextual and health system factors offered a much better explanation for the variations in DHS performance.

  3. Visual Assessment on Coastal Cruise Tourism: A Preliminary Planning Using Importance Performance Analysis

    Science.gov (United States)

    Trisutomo, S.

    2017-07-01

    Importance-Performance Analysis (IPA) has been widely applied in many cases. In this research, IPA was applied to measure perceive on coastal tourism objects and its possibility to be developed as coastal cruise tourism in Makassar. Three objects, i.e. Akkarena recreational site, Losari public space at waterfront, and Paotere traditional Phinisi ships port, were selected and assessed visually from water area by a group of purposive resource persons. The importance and performance of 10 attributes of each site were scored using Likert scale from 1 to 5. Data were processed by SPSS-21 than resulted Cartesian graph which the scores were divided in four quadrants: Quadrant I concentric here, Quadrant II keep up the good work, Quadrant III low priority, and Quadrant IV possible overkill. The attributes in each quadrant could be considered as the platform for preliminary planning of coastal cruise tour in Makassar

  4. Preliminary Analysis of the General Performance and Mechanical Behavior of Irradiated FeCrAl Base Alloys and Weldments

    Energy Technology Data Exchange (ETDEWEB)

    Gussev, Maxim N. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Field, Kevin G. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Briggs, Samuel A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Yamamoto, Yukinori [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-09-30

    The iron-based, iron-chromium-aluminum (FeCrAl) alloys are promising, robust materials for deployment in current and future nuclear power plants. This class of alloys demonstrates excellent performance in a range of environments and conditions, including high-temperature steam (>1000°C). Furthermore, these alloys have the potential to have prolonged survival under loss-of-coolant accident (LOCA) conditions compared to the more traditional cladding materials that are either Zr-based alloys or austenitic steels. However, one of the issues associated with FeCrAl alloys is cracking during welding. The present project investigates the possibility of mitigating welding-induced cracking via alloying and precise structure control of the weldments; in the frame work of the project, several advanced alloys were developed and are being investigated prior to and after neutron irradiation to provide insight into the radiation tolerance and mechanical performance of the weldments. The present report provides preliminary results on the post-irradiation characterization and mechanical tests performed during United States Fiscal Year (FY) 2016. Chapter 1 provides a general introduction, and Chapter 2 describes the alloy compositions, welding procedure, specimen geometry and manufacturing parameters. Also, a brief discussion of the irradiation at the High Flux Isotope Reactor (HFIR) is provided. Chapter 3 is devoted to the analysis of mechanical tests performed at the hot cell facility; tensile curves and mechanical properties are discussed in detail focusing on the irradiation temperature. Limited fractography results are also presented and analyzed. The discussion highlights the limitations of the testing within a hot cell. Chapter 4 underlines the advantages of in-situ testing and discusses the preliminary results obtained with newly developed miniature specimens. Specimens were moved to the Low Activation Materials Development and Analysis (LAMDA) laboratory and prepared for

  5. Review of cell performance in anion exchange membrane fuel cells

    Science.gov (United States)

    Dekel, Dario R.

    2018-01-01

    Anion exchange membrane fuel cells (AEMFCs) have recently received increasing attention since in principle they allow for the use of non-precious metal catalysts, which dramatically reduces the cost per kilowatt of power in fuel cell devices. Until not long ago, the main barrier in the development of AEMFCs was the availability of highly conductive anion exchange membranes (AEMs); however, improvements on this front in the past decade show that newly developed AEMs have already reached high levels of conductivity, leading to satisfactory cell performance. In recent years, a growing number of research studies have reported AEMFC performance results. In the last three years, new records in performance were achieved. Most of the literature reporting cell performance is based on hydrogen-AEMFCs, although an increasing number of studies have also reported the use of fuels others than hydrogen - such as alcohols, non-alcohol C-based fuels, as well as N-based fuels. This article reviews the cell performance and performance stability achieved in AEMFCs through the years since the first reports in the early 2000s.

  6. Five-Kilometers Time Trial: Preliminary Validation of a Short Test for Cycling Performance Evaluation.

    Science.gov (United States)

    Dantas, Jose Luiz; Pereira, Gleber; Nakamura, Fabio Yuzo

    2015-09-01

    The five-kilometer time trial (TT5km) has been used to assess aerobic endurance performance without further investigation of its validity. This study aimed to perform a preliminary validation of the TT5km to rank well-trained cyclists based on aerobic endurance fitness and assess changes of the aerobic endurance performance. After the incremental test, 20 cyclists (age = 31.3 ± 7.9 years; body mass index = 22.7 ± 1.5 kg/m(2); maximal aerobic power = 360.5 ± 49.5 W) performed the TT5km twice, collecting performance (time to complete, absolute and relative power output, average speed) and physiological responses (heart rate and electromyography activity). The validation criteria were pacing strategy, absolute and relative reliability, validity, and sensitivity. Sensitivity index was obtained from the ratio between the smallest worthwhile change and typical error. The TT5km showed high absolute (coefficient of variation 0.95) reliability of performance variables, whereas it presented low reliability of physiological responses. The TT5km performance variables were highly correlated with the aerobic endurance indices obtained from incremental test (r > 0.70). These variables showed adequate sensitivity index (> 1). TT5km is a valid test to rank the aerobic endurance fitness of well-trained cyclists and to differentiate changes on aerobic endurance performance. Coaches can detect performance changes through either absolute (± 17.7 W) or relative power output (± 0.3 W.kg(-1)), the time to complete the test (± 13.4 s) and the average speed (± 1.0 km.h(-1)). Furthermore, TT5km performance can also be used to rank the athletes according to their aerobic endurance fitness.

  7. Preliminary Feasibility Study on the Construction of Steel Hot Cell Facility for Precise Manipulated Examinations

    International Nuclear Information System (INIS)

    Ahn, Sangbok; Kwon, Hyungmun; Kim, Heemoon; Kim, Dosik; Min, Duckkee; Hong, Kwonpyo

    2006-01-01

    Hot laboratory is essential facility to research and develop in the nuclear industries to examine radioactive materials. The post irradiation examinations for irradiated fuels and materials should be mainly conducted in the hot cell facility to protect radiations to operators. Hot cells are divided into a concrete hot cell and a steel hot cell according to the wall materials. Usually a concrete hot cell is applied to test for high level radioactive materials like as a fuel assembly, rods, and large structure specimens, and a steel hot cell for comparatively lower level activity materials in fuel fragments, and small structural materials. A steel hot cell has many benefits in a specimen manipulation, construction and maintenance costs. In recent the test for the irradiated materials is more frequently required a small and precise manipulating examination for higher degree tests of research and developments. Unfortunately hot laboratory facilities in domestics have mainly constituted of concrete hot cells, and not ready for techniques in steel hot cells. In this paper the construction feasibility of steel hot cell facility is preliminary reviewed in the points of the status of domestic facilities, the test demand prospect and detailed plans

  8. Preliminary performance assessment for the Waste Isolation Pilot Plant, December 1992. Volume 3, Model parameters: Sandia WIPP Project

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-29

    This volume documents model parameters chosen as of July 1992 that were used by the Performance Assessment Department of Sandia National Laboratories in its 1992 preliminary performance assessment of the Waste Isolation Pilot Plant (WIPP). Ranges and distributions for about 300 modeling parameters in the current secondary data base are presented in tables for the geologic and engineered barriers, global materials (e.g., fluid properties), and agents that act upon the WIPP disposal system such as climate variability and human-intrusion boreholes. The 49 parameters sampled in the 1992 Preliminary Performance Assessment are given special emphasis with tables and graphics that provide insight and sources of data for each parameter.

  9. Behavior of HepG2 liver cancer cells using microfluidic-microscopy: a preliminary study

    Science.gov (United States)

    Karamahmutoglu, Hande; ćetin, Metin; Yaǧcı, Tamer; Elitaş, Meltem

    2018-02-01

    Hepatocellular carcinoma is one of the most common types of liver cancer causing death all over the world. Although early-stage liver cancer can sometimes be treated with partial hepatectomy, liver transplantation, ablation, and embolization, sorafenib treatment is the only approved systemic therapy for advanced HCC. The aim of this research is to develop tools and methods to understand the individuality of hepatocellular carcinoma. Microfluidic cell-culture platform has been developed to observe behavior of single-cells; fluorescence microscopy has been implemented to investigate phenotypic changes of cells. Our preliminary data proved high-level heterogeneity of hepatocellular carcinoma while verifying limited growth of liver cancer cell lines on the silicon wafer.

  10. Preliminary Evaluation of MapReduce for High-Performance Climate Data Analysis

    Science.gov (United States)

    Duffy, Daniel Q.; Schnase, John L.; Thompson, John H.; Freeman, Shawn M.; Clune, Thomas L.

    2012-01-01

    MapReduce is an approach to high-performance analytics that may be useful to data intensive problems in climate research. It offers an analysis paradigm that uses clusters of computers and combines distributed storage of large data sets with parallel computation. We are particularly interested in the potential of MapReduce to speed up basic operations common to a wide range of analyses. In order to evaluate this potential, we are prototyping a series of canonical MapReduce operations over a test suite of observational and climate simulation datasets. Our initial focus has been on averaging operations over arbitrary spatial and temporal extents within Modern Era Retrospective- Analysis for Research and Applications (MERRA) data. Preliminary results suggest this approach can improve efficiencies within data intensive analytic workflows.

  11. Preliminary assessment of adjuster system performance in CANDU-6 RUFIC core

    International Nuclear Information System (INIS)

    Kim, Soon Young; Suk, Ho Chun

    2002-07-01

    Four operational transients in CANDU-6 RUFIC core have been simulated to assess the adjuster system performance. These transients included startup after a short shutdown, startup after a poison-out shutdown, shim mode operation, and a stepback to 60% full power. Also, an alternative adjuster-banking scheme has been assessed in this report. The alternative adjuster-banking scheme involves rods in Bank 1 and Bank 7 being re-distributed within the two banks. In the alternative adjuster-banking scheme, Bank 1 becomes the heaviest one. The results of the preliminary assessment indicated that the adjuster system as currently designed and installed in the NU core will adequately meet the functional requirements in the RUFIC core. Comparing to the adjuster system performance in the NU core, the total worth of the adjuster in the RUFIC core is reduced, leading to less xenon override capability and shimming capability. However, the overall performance is expected to still be satisfactory. The overall results from the transient studied indicated that the alternative banking scheme does show some better performance characteristics and merits further detailed studies

  12. A preliminary study for constructing a bioartificial liver device with induced pluripotent stem cell-derived hepatocytes

    Directory of Open Access Journals (Sweden)

    Iwamuro Masaya

    2012-12-01

    Full Text Available Abstract Background Bioartificial liver systems, designed to support patients with liver failure, are composed of bioreactors and functional hepatocytes. Immunological rejection of the embedded hepatocytes by the host immune system is a serious concern that crucially degrades the performance of the device. Induced pluripotent stem (iPS cells are considered a desirable source for bioartificial liver systems, because patient-derived iPS cells are free from immunological rejection. The purpose of this paper was to test the feasibility of a bioartificial liver system with iPS cell-derived hepatocyte-like cells. Methods Mouse iPS cells were differentiated into hepatocyte-like cells by a multi-step differentiation protocol via embryoid bodies and definitive endoderm. Differentiation of iPS cells was evaluated by morphology, PCR assay, and functional assays. iPS cell-derived hepatocyte-like cells were cultured in a bioreactor module with a pore size of 0.2 μm for 7 days. The amount of albumin secreted into the circulating medium was analyzed by ELISA. Additionally, after a 7-day culture in a bioreactor module, cells were observed by a scanning electron microscope. Results At the final stage of the differentiation program, iPS cells changed their morphology to a polygonal shape with two nucleoli and enriched cytoplasmic granules. Transmission electron microscope analysis revealed their polygonal shape, glycogen deposition in the cytoplasm, microvilli on their surfaces, and a duct-like arrangement. PCR analysis showed increased expression of albumin mRNA over the course of the differentiation program. Albumin and urea production was also observed. iPS-Heps culture in bioreactor modules showed the accumulation of albumin in the medium for up to 7 days. Scanning electron microscopy revealed the attachment of cell clusters to the hollow fibers of the module. These results indicated that iPS cells were differentiated into hepatocyte-like cells after culture

  13. Cell shunt resistance and photovoltaic module performance

    Energy Technology Data Exchange (ETDEWEB)

    McMahon, T.J.; Basso, T.S.; Rummel, S.R. [National Renewable Energy Lab., Golden, CO (United States)

    1996-05-01

    Shunt resistance of cells in photovoltaic modules can affect module power output and could indicate flawed manufacturing processes and reliability problems. The authors describe a two-terminal diagnostic method to directly measure the shunt resistance of individual cells in a series-connected module non-intrusively, without deencapsulation. Peak power efficiency vs. light intensity was measured on a 12-cell, series-connected, single crystalline module having relatively high cell shunt resistances. The module was remeasured with 0.5-, 1-, and 2-ohm resistors attached across each cell to simulate shunt resistances of several emerging technologies. Peak power efficiencies decreased dramatically at lower light levels. Using the PSpice circuit simulator, the authors verified that cell shunt and series resistances can indeed be responsible for the observed peak power efficiency vs. intensity behavior. The authors discuss the effect of basic cell diode parameters, i.e., shunt resistance, series resistance, and recombination losses, on PV module performance as a function of light intensity.

  14. An Algorithm for Glaucoma Screening in Clinical Settings and Its Preliminary Performance Profile

    Directory of Open Access Journals (Sweden)

    S-Farzad Mohammadi

    2013-01-01

    Full Text Available Purpose: To devise and evaluate a screening algorithm for glaucoma in clinical settings. Methods: Screening included examination of the optic disc for vertical cupping (≥0.4 and asymmetry (≥0.15, Goldmann applanation tonometry (≥21 mmHg, adjusted or unadjusted for central corneal thickness, and automated perimetry. In the diagnostic step, retinal nerve fiber layer imaging was performed using scanning laser polarimetry. Performance of the screening protocol was assessed in an eye hospital-based program in which 124 non-physician personnel aged 40 years or above were examined. A single ophthalmologist carried out the examinations and in equivocal cases, a glaucoma subspecialist′s opinion was sought. Results: Glaucoma was diagnosed in six cases (prevalence 4.8%; 95% confidence interval, 0.01-0.09 of whom five were new. The likelihood of making a definite diagnosis of glaucoma for those who were screened positively was 8.5 times higher than the estimated baseline risk for the reference population; the positive predictive value of the screening protocol was 30%. Screening excluded 80% of the initial population. Conclusion: Application of a formal screening protocol (such as our algorithm or its equivalent in clinical settings can be helpful in detecting new cases of glaucoma. Preliminary performance assessment of the algorithm showed its applicability and effectiveness in detecting glaucoma among subjects without any visual complaint.

  15. Barrier analogs: Long-term performance issues, preliminary studies, and recommendations

    Energy Technology Data Exchange (ETDEWEB)

    Waugh, W.J. [Rust Geotech, Inc., Grand Junction, CO (United States). Environmental Sciences Lab.; Chatters, J.C.; Last, G.V.; Bjornstad, B.N.; Link, S.O. [Pacific Northwest Lab., Richland, WA (United States); Hunter, C.R. [Cascade Earth Sciences, La Grande, OR (United States)

    1994-02-01

    The US Department of Energy`s Hanford Protective Barrier Development Program is funding studies of natural analogs of the long-term performance of waste site covers. Natural-analog studies examine past environments as evidence for projecting the future performance of engineered structures. The information generated by analog studies is needed to (1) evaluate the designs and results of short term experiments and demonstrations, (2) formulate performance-modeling problems that bound expected changes in waste site environments, and (3) understand emergent system attributes that cannot be evaluated with short-term experiments or computer models. Waste site covers will be part of dynamic environmental systems with attributes that transcend the traits of engineered components. This report discusses results of the previously unreported preliminary studies conducted in 1983 and 1984. These results indicate that analogs could play an important role in predicting the long-term behavior of engineered waste covers. Layered exposures of glacial-flood-deposited gravels mantled with silt or sand that resemble contemporary barrier designs were examined. Bergmounds, another anomaly left by cataclysmic glacial floods, were also examined as analogs of surface gravel.

  16. New technologies and new performances of the JCMT radio-telescope: a preliminary design study

    Science.gov (United States)

    Mian, S.; De Lorenzi, S.; Ghedin, L.; Rampini, F.; Marchiori, G.; Craig, S.

    2012-09-01

    With a diameter of 15m the James Clerk Maxwell Telescope (JCMT) is the largest astronomical telescope in the world designed specifically to operate in the submillimeter wavelength region of the spectrum. It is situated close to the summit of Mauna Kea, Hawaii, at an altitude of 4092m. Its primary reflector currently consists of a steel geodesic supporting structure and pressed aluminium panels on a passive mount. The major issues of the present reflector are its thermal stability and its panels deterioration. A preliminary design study for the replacement of the JCMT antenna dish is here presented. The requested shape error for the new reflector is <20μm RMS. The proposed solution is based on a semi-monocoque backing structure made of CFRP and on high precision electroformed panels. The choice of CFRP for the backing structure allows indeed to improve the antenna performance in terms of both stiffness and thermal stability, so that the required surface accuracy of the primary can be achieved even by adopting a passive panels system. Moreover thanks to CFRP, a considerable weight reduction of the elevation structure can be attained. The performance of the proposed solution for the JCMT antenna has been investigated through FE analyses and the assessed deformation of the structure under different loading cases has been taken into account for subsequent error budgeting. Results show that the proposed solution is in line with the requested performance. With this new backing structure, the JCMT would have the largest CFRP reflector ever built.

  17. The Preliminary Research for Implementation of Improved DTC Scheme of High Performance PMSM Drives

    Directory of Open Access Journals (Sweden)

    Tole Sutikno

    2008-12-01

    Full Text Available The direct torque control (DTC is one of control approache that is used commonly in PMSM control system. This method supports a very quick and precise torque response. However, the DTC method is not perfect and has some disadvantages. Many researchers have been proposed to modify the basic DTC scheme for PMSM drive. All this contributions allow performance to be improved, but at the same time they lead to more complex schemes. Furthermore, the PMSM drive control systems are usually based on microcontroller and DSP. Some researchers also have been used DSP and FPGA together to develop DTC for AC drives. These allow improving the performance, but they will increase cost. For the reason above, this paper proposed a new DTC scheme to apply only based on FPGA. The preliminary research showed that the proposed DTC sheme can reduce torque and flux ripples significantly. Therefore, this paper also recomend to realize proposed DTC scheme based on FPGA in order to support to execute very fast computation.The implementation is hoped that it will very potential to replace not only the induction motor but also the DC servo motor in a number of industrial process, commercial, domestic and modern military applications of high-performance drive.

  18. Progress in static fourier transform infrared spectroscopy: assessment of sifti preliminary performances

    Science.gov (United States)

    Hébert, Philippe; Pierangelo, Clémence; Rosak, Alain; Cansot, Elodie; Bernard, Frédéric; Camy-Peyret, Claude

    2017-11-01

    The concept of static Fourier transform interferometry at thermal infrared wavelengths is well suited in the case of narrow spectral bands that are looked at for targeted molecular species as CO and O3 for pollution and air quality monitoring, or H20 and CO2 for weather forecast, down to the troposphere. It permits a high spectral resolution and a very good radiometric performance, with the advantage of a static interferometer, including no moving part. Along with other molecules sounded in the UV-VIS domain, as for instance in the TRAQ mission, SIFTI will provide scientists with a complete set for pollution measurements and air quality survey. Our paper presents the principles of static Fourier transform spectrometry, the work led on the instrument performance model and our study of the SIFTI instrument. We describe the instrument, its main dimensions and characteristics, and its architecture and major subsystems. We eventually make a preliminary survey of the SIFTI performance budget items. As a conclusion, we introduce the future CNES phase A study of this instrument that is started in 2006

  19. A preliminary study on the association between ventilation rates in classrooms and student performance.

    Science.gov (United States)

    Shaughnessy, R J; Haverinen-Shaughnessy, U; Nevalainen, A; Moschandreas, D

    2006-12-01

    Poor conditions leading to substandard indoor air quality (IAQ) in classrooms have been frequently cited in the literature over the past two decades. However, there is limited data linking poor IAQ in the classrooms to student performance. Whereas, it is assumed that poor IAQ results in reduced attendance and learning potential, and subsequent poor student performance, validating this hypothesis presents a challenge in today's school environment. This study explores the association between student performance on standardized aptitude tests that are administered to students on a yearly basis, to classroom carbon dioxide (CO2) concentrations, which provide a surrogate of ventilation being provided to each room. Data on classroom CO2 concentrations (over a 4-5 h time span within a typical school day) were recorded in fifth grade classrooms in 54 elementary schools within a school district in the USA. Results from this preliminary study yield a significant (P classroom-level ventilation rate and test results in math. They also indicate that non-linear effects may need to be considered for better representation of the association. A larger sample size is required in order to draw more definitive conclusions. Practical Implications Future studies could focus on (1) gathering more evidence on the possible association between classroom ventilation rates and students' academic performance; (2) the linear/non-linear nature of the association; and (3) whether it is possible to detect 'no observed adverse effect level' for adequate ventilation with respect to academic performance in schools. All of this information could be used to improve guidance and take regulatory actions to ensure adequate ventilation in schools. The high prevalence of low ventilation rates, combined with the growing evidence of the positive impact that sufficient ventilation has on human performance, suggests an opportunity for improving design and management of school facilities.

  20. Preliminary estimation of the dose rates of the operation room of the RPR radioisotope cell

    International Nuclear Information System (INIS)

    Rocha, A.C.S.; Silva, J.J.G.; Pina, J.L.S. de; Fajardo, P.W.

    1986-07-01

    During the preliminary studies, about the installations layout of a radioisotope production reactor, the possibility of construction of a radioisotope cell at the reactor building has been investigated. The decisions about that construction has considered mainly the level of the radiation dose over the cell operator. The dose rate has been calculated based on: neutron flux and gamma radiation from fission products and activation materials inside the reactor; volatile fission products such as noble gases and iodides; tritium form ternary fission. The objective was calculate the radiation dose over the cell operator during a journey of 8 hours of work per day. For those calculations some data have been obtained from the Angra-3 reactor. (author)

  1. Modelling fuel cell performance using artificial intelligence

    Science.gov (United States)

    Ogaji, S. O. T.; Singh, R.; Pilidis, P.; Diacakis, M.

    Over the last few years, fuel cell technology has been increasing promisingly its share in the generation of stationary power. Numerous pilot projects are operating worldwide, continuously increasing the amount of operating hours either as stand-alone devices or as part of gas turbine combined cycles. An essential tool for the adequate and dynamic analysis of such systems is a software model that enables the user to assess a large number of alternative options in the least possible time. On the other hand, the sphere of application of artificial neural networks has widened covering such endeavours of life such as medicine, finance and unsurprisingly engineering (diagnostics of faults in machines). Artificial neural networks have been described as diagrammatic representation of a mathematical equation that receives values (inputs) and gives out results (outputs). Artificial neural networks systems have the capacity to recognise and associate patterns and because of their inherent design features, they can be applied to linear and non-linear problem domains. In this paper, the performance of the fuel cell is modelled using artificial neural networks. The inputs to the network are variables that are critical to the performance of the fuel cell while the outputs are the result of changes in any one or all of the fuel cell design variables, on its performance. Critical parameters for the cell include the geometrical configuration as well as the operating conditions. For the neural network, various network design parameters such as the network size, training algorithm, activation functions and their causes on the effectiveness of the performance modelling are discussed. Results from the analysis as well as the limitations of the approach are presented and discussed.

  2. Modelling fuel cell performance using artificial intelligence

    Energy Technology Data Exchange (ETDEWEB)

    Ogaji, S.O.T.; Singh, R.; Pilidis, P.; Diacakis, M. [Power Propulsion and Aerospace Engineering Department, Centre for Diagnostics and Life Cycle Costs, Cranfield University (United Kingdom)

    2006-03-09

    Over the last few years, fuel cell technology has been increasing promisingly its share in the generation of stationary power. Numerous pilot projects are operating worldwide, continuously increasing the amount of operating hours either as stand-alone devices or as part of gas turbine combined cycles. An essential tool for the adequate and dynamic analysis of such systems is a software model that enables the user to assess a large number of alternative options in the least possible time. On the other hand, the sphere of application of artificial neural networks has widened covering such endeavours of life such as medicine, finance and unsurprisingly engineering (diagnostics of faults in machines). Artificial neural networks have been described as diagrammatic representation of a mathematical equation that receives values (inputs) and gives out results (outputs). Artificial neural networks systems have the capacity to recognise and associate patterns and because of their inherent design features, they can be applied to linear and non-linear problem domains. In this paper, the performance of the fuel cell is modelled using artificial neural networks. The inputs to the network are variables that are critical to the performance of the fuel cell while the outputs are the result of changes in any one or all of the fuel cell design variables, on its performance. Critical parameters for the cell include the geometrical configuration as well as the operating conditions. For the neural network, various network design parameters such as the network size, training algorithm, activation functions and their causes on the effectiveness of the performance modelling are discussed. Results from the analysis as well as the limitations of the approach are presented and discussed. (author)

  3. Preliminary Analysis of Remote Monitoring and Robotic Concepts for Performance Confirmation

    International Nuclear Information System (INIS)

    McAffee, D.A.

    1997-01-01

    main Performance Confirmation monitoring needs and requirements during the post-emplacement preclosure period. This includes radiological, non-radiological, host rock, and infrastructure performance monitoring needs. It also includes monitoring for possible off-normal events. (Presented in Section 7.3). (3) Identify general approaches and methods for obtaining performance information from within the emplacement drifts for Performance Confirmation. (Presented in Section 7.4) (4)Review and discuss available technologies and design strategies that may permit the use of remotely operated systems within the hostile thermal and radiation environment expected within the emplacement drifts. (Presented in Section 7.5). (5) Based on Performance Confirmation monitoring needs and available technologies, identify potential application areas for remote systems and robotics for post-emplacement preclosure Performance Confirmation activities (Presented in Section 7.6). (6) Develop preliminary remote monitoring and robotic concepts for post-emplacement, preclosure Performance Confirmation activities. (Presented in Section 7.7) This analysis is being performed very early in the systems engineering cycle, even as issues related to the Performance Confirmation program planning phase are being formulated and while the associated needs, constraints and objectives are yet to be fully determined and defined. This analysis is part of an issue formulation effort and is primarily concerned with identification and description of key issues related to remotely monitoring repository performance for Performance Confirmation. One of the purposes of this analysis is to provide an early investigation of potential design challenges that may have a high impact on future design concepts. This analysis can be used to guide future concept development and help access what is feasible and achievable by application of remote systems technology. Future design and systems engineering analysis with applicable

  4. Methodology for the preliminary design of high performance schools in hot and humid climates

    Science.gov (United States)

    Im, Piljae

    A methodology to develop an easy-to-use toolkit for the preliminary design of high performance schools in hot and humid climates was presented. The toolkit proposed in this research will allow decision makers without simulation knowledge easily to evaluate accurately energy efficient measures for K-5 schools, which would contribute to the accelerated dissemination of energy efficient design. For the development of the toolkit, first, a survey was performed to identify high performance measures available today being implemented in new K-5 school buildings. Then an existing case-study school building in a hot and humid climate was selected and analyzed to understand the energy use pattern in a school building and to be used in developing a calibrated simulation. Based on the information from the previous step, an as-built and calibrated simulation was then developed. To accomplish this, five calibration steps were performed to match the simulation results with the measured energy use. The five steps include: (1) Using an actual 2006 weather file with measured solar radiation, (2) Modifying lighting & equipment schedule using ASHRAE's RP-1093 methods, (3) Using actual equipment performance curves (i.e., scroll chiller), (4) Using the Winkelmann's method for the underground floor heat transfer, and (5) Modifying the HVAC and room setpoint temperature based on the measured field data. Next, the calibrated simulation of the case-study K-5 school was compared to an ASHRAE Standard 90.1-1999 code-compliant school. In the next step, the energy savings potentials from the application of several high performance measures to an equivalent ASHRAE Standard 90.1-1999 code-compliant school. The high performance measures applied included the recommendations from the ASHRAE Advanced Energy Design Guides (AEDG) for K-12 and other high performance measures from the literature review as well as a daylighting strategy and solar PV and thermal systems. The results show that the net

  5. Instrumental concept and preliminary performances of SIFTI: static infrared fourier transform interferometer

    Science.gov (United States)

    Hébert, Philippe-Jean; Cansot, E.; Pierangelo, C.; Buil, C.; Bernard, F.; Loesel, J.; Trémas, T.; Perrin, L.; Courau, E.; Casteras, C.; Maussang, I.; Simeoni, D.

    2017-11-01

    The SIFTI (Static Infrared Fourier Transform Interferometer) instrument aims at supporting an important part in a mission for atmospheric pollution sounding from space, by providing high spectral resolution and high Signal to Noise Ratio spectra of the atmosphere. They will allow to resolve tropospheric profiles of ozone (03) and carbon monoxide (C0), especially down to the planetary boundary layer (PBL), an altitude region of very high interest, though poorly monitored to date, for air quality and pollution monitoring. The retrieved profile of ozone, resp. C0, will contain 5 to 7, resp. 2.5 to 4, independent pieces of information. The French space agency CNES (Centre National d'Etudes Spatiales) has proposed and is studying an instrument concept for SIFTI based on a static interferometer, where the needed optical path are generated by a pair of crossed staircase fixed mirrors (replacing the moving reflector of dynamic Fourier transform interferometers like IASI or MIPAS). With the SIFTI design, a very high spectral resolution ( 0.1 cm-1 apodised) is achieved in a very compact optical setup, allowing a large throughput, hence a high SNR. The measurements are performed in the 9.5 μm band for 03 and in the 4.6 μm band for C0. The science return of the sounder can be further increased if an "intelligent pointing" process is implemented. This consists in combining the TIR sounder with a companion TIR imager, providing information on the cloud coverage in the next observed scene. 0nboard, real-time analysis of the IR image is used to command the sounder staring mirror to cloud free areas, which will maximize the probability for probing down to the surface. After the first part of the phase A, the architecture of SIFTI was studied as a trade-off between performance and resource budget. We review the main architecture and functional choices, and their advantages. The preliminary instrument concept is then presented in its main aspects and in terms of main subsystem

  6. Examining implementation and preliminary performance indicators of veterans treatment courts: The Kentucky experience.

    Science.gov (United States)

    Shannon, Lisa M; Birdwhistell, Shira; Hulbig, Shelia K; Jones, Afton Jackson; Newell, Jennifer; Payne, Connie

    2017-08-01

    Veterans' Treatment Courts (VTCs) are posited as a solution to offer rehabilitation for veterans involved in the criminal justice system. Despite the pervasive implementation of VTCs, there is little research focused specifically on VTC implementation and outcomes, which are based on other problem-solving court models such as drug court. The current study presents qualitative process evaluation data from key stakeholders (n=21) and veteran participants (n=4) to show accomplishments, challenges, and lessons learned during first-year implementation at two VTC sites. Quantitative performance data is also presented on veteran participants (n=19) served during the first year to show: types of services, monitoring, judicial interaction, sanctions/therapeutic responses, and rewards, as well as preliminary data on recidivism. Qualitative data, from both key stakeholders and veteran participants, suggests that offering rehabilitation via various program components, services/referrals, and accountability are critical to the success of the VTC. Data also provides valuable lessons learned for VTC implementation including communication, collaboration, information/protocols, and resources. Performance data shows that a variety of services are utilized and that frequent judicial interaction, drug testing, and sanctions are cornerstones of the VTC. Implications and future directions for research are discussed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Preliminary Evaluation Methodology of ECCS Performance for Design Basis LOCA Redefinition

    International Nuclear Information System (INIS)

    Kang, Dong Gu; Ahn, Seung Hoon; Seul, Kwang Won

    2010-01-01

    To improve their existing regulations, the USNRC has made efforts to develop the risk-informed and performance-based regulation (RIPBR) approaches. As a part of these efforts, the rule revision of 10CFR50.46 (ECCS Acceptance Criteria) is underway, considering some options for 4 categories of spectrum of break sizes, ECCS functional reliability, ECCS evaluation model, and ECCS acceptance criteria. Since the potential for safety benefits and unnecessary burden reduction from design basis LOCA redefinition is high relative to other options, the USNRC is proceeding with the rulemaking for design basis LOCA redefinition. An instantaneous break with a flow rate equivalent to a double ended guillotine break (DEGB) of the largest primary piping system in the plant is widely recognized as an extremely unlikely event, while redefinition of design basis LOCA can affect the existing regulatory practices and approaches. In this study, the status of the design basis LOCA redefinition and OECD/NEA SMAP (Safety Margin Action Plan) methodology are introduced. Preliminary evaluation methodology of ECCS performance for LOCA is developed and discussed for design basis LOCA redefinition

  8. Performance adaptive training control strategy for recovering wrist movements in stroke patients: a preliminary, feasibility study

    Directory of Open Access Journals (Sweden)

    Sandini Giulio

    2009-12-01

    Full Text Available Abstract Background In the last two decades robot training in neuromotor rehabilitation was mainly focused on shoulder-elbow movements. Few devices were designed and clinically tested for training coordinated movements of the wrist, which are crucial for achieving even the basic level of motor competence that is necessary for carrying out ADLs (activities of daily life. Moreover, most systems of robot therapy use point-to-point reaching movements which tend to emphasize the pathological tendency of stroke patients to break down goal-directed movements into a number of jerky sub-movements. For this reason we designed a wrist robot with a range of motion comparable to that of normal subjects and implemented a self-adapting training protocol for tracking smoothly moving targets in order to facilitate the emergence of smoothness in the motor control patterns and maximize the recovery of the normal RoM (range of motion of the different DoFs (degrees of Freedom. Methods The IIT-wrist robot is a 3 DoFs light exoskeleton device, with direct-drive of each DoF and a human-like range of motion for Flexion/Extension (FE, Abduction/Adduction (AA and Pronation/Supination (PS. Subjects were asked to track a variable-frequency oscillating target using only one wrist DoF at time, in such a way to carry out a progressive splinting therapy. The RoM of each DoF was angularly scanned in a staircase-like fashion, from the "easier" to the "more difficult" angular position. An Adaptive Controller evaluated online performance parameters and modulated both the assistance and the difficulty of the task in order to facilitate smoother and more precise motor command patterns. Results Three stroke subjects volunteered to participate in a preliminary test session aimed at verify the acceptability of the device and the feasibility of the designed protocol. All of them were able to perform the required task. The wrist active RoM of motion was evaluated for each patient at the

  9. A preliminary study on performance of Saccharomyces cerevisiae n0 DY 7221 immobilized using grafted bioflocculant in bioethanol production

    Science.gov (United States)

    Suci, Windhu Griyasti; Margono, Kaavessina, Mujtahid

    2018-02-01

    Bioethanol has been well acknowledged to be developed as a biofuel and can be derived from renewable resources. Currently, the utilization of bioethanol as a fuel is more expensive than that of gasoline due to the high production cost. Researchers from industrial and academia have been doing some efforts to reduce it, namely: energy efficiency, exploring many potential renewable resources, increasing fermentation productivity, etc. We propose a novel immobilized Saccharomyces cerevisiae trapped in grafted bioflocculant. The flocculant was developed from polyacrylamide chains grafted into modified starches. This research aims to preliminary performance study of S. cerevisiae immobilized using our new developed method. The bioflocculant solution with the various concentration of 1%, 2%, and 2.5% v/v was dropped into 90 ml of developed inoculum to get flocs which would be used as a starter in fermentation process. The fermentation process was carried out in a shaken flask at 30oC and 150 rpm for 72 hours. The best result was obtained in the sample of 2.5% bioflocculant fraction, i.e. bioethanol 9.25% and enhanced productivity 3.6 times of free cell. These results indicate that flocculation method is a way of immobilizing yeast that needs to be further investigated.

  10. Preliminary Study on Testicular Germ Cell Transplantation of Endemic Species Oryzias celebensis

    Science.gov (United States)

    Andriani, I.; Agustiani, F.; Hassan, M.; Parenrengi, A.; Inoue, K.

    2018-03-01

    The research has been conducted to study some technical steps for male germ-plasm from endemic fish species such as some species of Oryzias fish in Indonesia to preserve and propagate through germ cell transplantation technology. For preliminary research, the study was started with germ cell characterization of testes, cryopreservation of TGC and the transplantation of Oryzias celebensis as candidates for surrogate broodstock of Oryzias fish male germ plasm. The data analized included the potential number of TGC as donor, the viability of cryopreserved TGC in two types of cryoprotectans and the survival rate of O.celebensis larvae as recipient after transplantation. The result showed that the average amount of TGC yielded after dissociation was 131000 ± 31349 with 74.2 % viability of TGC each. Cryoprotectan10% DMSO +glucose yielded higher viable of TGC. More than 80 % of O.celebensis larvae survived after transplantation. In conclusion, these preliminary data of O.celebensis as surrogate broodstock candidate will support the application of TGC transplantation technology in Oryzias endemic species.

  11. Cell kinetics of gastrointestinal tumors after different nutritional regimens. A preliminary report

    International Nuclear Information System (INIS)

    Franchi, F.; Rossi-Fanelli, F.; Seminara, P.; Cascino, A.; Barone, C.; Scucchi, L.

    1991-01-01

    Forty-four cases of different untreated gastrointestinal tumors were studied with regard to cell kinetic activity. As a pilot experiment, the authors also determined the 3H-TdR Labeling Index (LI) in 28 patients in basal conditions and after 15 days of nutritional manipulation with prevalently lipid-based or glucose-based feeding to ascertain whether selective nutritional regimens could affect tumor proliferation. Preliminary results from this study indicate that a kinetic perturbation is induced in tumor cells by nutritional manipulation. Lipid-based feeding seems to produce effects similar to those of chemical or physical anticancer agents, thus suggesting a possible supporting role of nutritional manipulation in cancer treatment strategy

  12. A comparison of the recruitment of antibody forming cells in the nose and lung: Preliminary findings

    Energy Technology Data Exchange (ETDEWEB)

    King-Herbert, A P; Bice, D E; Harkema, J R

    1988-12-01

    Instillation of a particulate antigen into a selected lung lobe leads to an accumulation of antibody forming cells in the exposed lung lobe. Our goal in this preliminary study was to determine if an immune response could be elicited in the nasal mucosa of Beagle dogs exposed to a particulate antigen, and if so, to compare this immune response with that of the lungs when the nasal mucosa and the lungs are each immunized with a different particulate antigen. An Immune response was observed when the nasal mucosa was exposed to particulate antigen, but numbers of antibody-forming cells and levels of antibody in the nose were much lower than observed in an immunized lung lobe. (author)

  13. A comparison of the recruitment of antibody forming cells in the nose and lung: Preliminary findings

    International Nuclear Information System (INIS)

    King-Herbert, A.P.; Bice, D.E.; Harkema, J.R.

    1988-01-01

    Instillation of a particulate antigen into a selected lung lobe leads to an accumulation of antibody forming cells in the exposed lung lobe. Our goal in this preliminary study was to determine if an immune response could be elicited in the nasal mucosa of Beagle dogs exposed to a particulate antigen, and if so, to compare this immune response with that of the lungs when the nasal mucosa and the lungs are each immunized with a different particulate antigen. An Immune response was observed when the nasal mucosa was exposed to particulate antigen, but numbers of antibody-forming cells and levels of antibody in the nose were much lower than observed in an immunized lung lobe. (author)

  14. Preliminary Performance Analysis Program Development for Safety System with Safeguard Vessel

    International Nuclear Information System (INIS)

    Kang, Han-Ok; Lee, Jun; Park, Cheon-Tae; Yoon, Ju-Hyeon; Park, Keun-Bae

    2007-01-01

    SMART is an advanced modular integral type pressurized water reactor for a seawater desalination and an electricity production. Major components of the reactor coolant system such as the pressurizer, Reactor Coolant Pump (RCP), and steam generators are located inside the reactor vessel. The SMART can fundamentally eliminate the possibility of large break loss of coolant accidents (LBLOCAs), improve the natural circulation capability, and better accommodate and thus enhance a resistance to a wide range of transients and accidents. The safety goals of the SMART are enhanced through highly reliable safety systems such as the passive residual heat removal system (PRHRS) and the safeguard vessel coupled with the passive safety injection feature. The safeguard vessel is a steel-made, leak-tight pressure vessel housing the RPV, SIT, and the associated valves and pipelines. A primary function of the safeguard vessel is to confine any radioactive release from the primary circuit within the vessel under DBAs related to loss of the integrity of the primary system. A preliminary performance analysis program for a safety system using the safeguard vessel is developed in this study. The developed program is composed of several subroutines for the reactor coolant system, passive safety injection system, safeguard vessel including the pressure suppression pool, and PRHRS. A small break loss of coolant accident at the upper part of a reactor is analyzed and the results are discussed

  15. Preliminary effects of pagoclone, a partial GABAA agonist, on neuropsychological performance

    Directory of Open Access Journals (Sweden)

    Angela F Caveney

    2008-03-01

    Full Text Available Angela F Caveney1, Bruno Giordani1, George M Haig21Department of Psychiatry, University of Michigan, Ann Arbor, MI, USA; 2Neurosciences Development, Abbott Laboratories, Abbott Park, IL, USAAbstract: Pagoclone is a novel cyclopyrrolone that acts as a partial GABAA receptor agonist. Preclinical studies suggest that pagoclone may have clinical utility as an anxiolytic agent, as well as a reduced incidence of side-effects. The present study was conducted to determine whether pagoclone would affect healthy individuals’ performances on neuropsychological measures as a function of dose within the projected therapeutic range. Twelve healthy adult subjects were randomly assigned to dosage groups in a 3-way crossover study. Participants were administered neuropsychological measures six hours following dosing on Day 1 and Day 6 of administration of the drug. Dose effects were noted on measures of alertness, learning, and memory and movement time. Significant effects were also noted on measures of alertness, learning and memory, information processing and psychomotor speed. Overall, the results of this small, preliminary study do not support a finding of behavioral toxicity for these doses of pagoclone. Rather, a pattern was found of transient and mild negative effects on learning and memory scores at the highest dose administered, though these changes were small and no longer evident by the sixth day of use.Keywords: pagoclone, cyclopyrrolone, neuropsychological, memory, generalized anxiety disorder

  16. Accelerated stress testing of thin film solar cells: Development of test methods and preliminary results

    Science.gov (United States)

    Lathrop, J. W.

    1985-01-01

    If thin film cells are to be considered a viable option for terrestrial power generation their reliability attributes will need to be explored and confidence in their stability obtained through accelerated testing. Development of a thin film accelerated test program will be more difficult than was the case for crystalline cells because of the monolithic construction nature of the cells. Specially constructed test samples will need to be fabricated, requiring committment to the concept of accelerated testing by the manufacturers. A new test schedule appropriate to thin film cells will need to be developed which will be different from that used in connection with crystalline cells. Preliminary work has been started to seek thin film schedule variations to two of the simplest tests: unbiased temperature and unbiased temperature humidity. Still to be examined are tests which involve the passage of current during temperature and/or humidity stress, either by biasing in the forward (or reverse) directions or by the application of light during stress. Investigation of these current (voltage) accelerated tests will involve development of methods of reliably contacting the thin conductive films during stress.

  17. The Effects of Battalion Staff Stabilization on Individual and Unit Performance: A Preliminary Investigation

    National Research Council Canada - National Science Library

    Ardison, Sharon

    2001-01-01

    ... (six of the seven units). Although improvements in leadership skills and abilities were associated with longer command team tenure, the results are those of a preliminary investigation and not intended for generalization to the Army-at-large.

  18. A preliminary report on stem cell therapy for neuropathic pain in humans

    Directory of Open Access Journals (Sweden)

    Vickers ER

    2014-05-01

    Full Text Available E Russell Vickers,1 Elisabeth Karsten,2 John Flood,3 Richard Lilischkis21Sydney Oral and Maxillofacial Surgery, NSW, Australia; 2Regeneus Ltd, Gordon, NSW, Australia; 3St Vincents Hospital, Sydney, NSW, AustraliaObjective: Mesenchymal stem cells (MSCs have been shown in animal models to attenuate chronic neuropathic pain. This preliminary study investigated if: i injections of autologous MSCs can reduce human neuropathic pain and ii evaluate the safety of the procedure.Methods: Ten subjects with symptoms of neuropathic trigeminal pain underwent liposuction. The lipoaspirate was digested with collagenase and washed with saline three times. Following centrifugation, the stromal vascular fraction was resuspended in saline, and then transferred to syringes for local injections into the pain fields. Outcome measures at 6 months assessed reduction in: i pain intensity measured by standard numerical rating scale from 0–10 and ii daily dosage requirements of antineuropathic pain medication.Results: Subjects were all female (mean age 55.3 years ± standard deviation [SD] 14.67; range 27–80 years with pain symptoms lasting from 4 months to 6 years and 5 months. Lipoaspirate collection ranged from 102–214 g with total cell numbers injected from 33 million to 162 million cells. Cell viability was 62%–91%. There were no systemic or local tissue side effects from the stem cell therapy (n=41 oral and facial injection sites. Clinical pain outcomes showed that at 6 months, 5/9 subjects had reduced both pain intensity scores and use of antineuropathic medication. The mean pain score pre-treatment was 7.5 (SD 1.58 and at 6 months had decreased to 4.3 (SD 3.28, P=0.018, Wilcoxon signed-rank test. Antineuropathic pain medication use showed 5/9 subjects reduced their need for medication (gabapentin, P=0.053, Student's t-test.Conclusion: This preliminary open-labeled study showed autologous administration of stem cells for neuropathic trigeminal pain

  19. Preliminary performance assessment for the Waste Isolation Pilot Plant, December 1992

    International Nuclear Information System (INIS)

    1993-08-01

    Before disposing of transuranic radioactive waste in the Waste Isolation Pilot Plant (WIPP), the United States Department of Energy (DOE) must evaluate compliance with applicable long-term regulations of the United States Environmental Protection Agency (EPA). Sandia National Laboratories is conducting iterative performance assessments (PAs) of the WIPP for the DOE to provide interim guidance while preparing for a final compliance evaluation. This volume of the 1992 PA contains results of uncertainty and sensitivity analyses with respect to migration of gas and brine from the undisturbed repository. Additional information about the 1992 PA is provided in other volumes. Volume 1 contains an overview of WIPP PA and results of a preliminary comparison with 40 CFR 191, Subpart B. Volume 2 describes the technical basis for the performance assessment, including descriptions of the linked computational models used in the Monte Carlo analyses. Volume 3 contains the reference data base and values for input parameters used in consequence and probability modeling. Volume 4 contains uncertainty and sensitivity analyses with respect to the EPA's Environmental Standards for the Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes (40 CFR 191, Subpart B). Finally, guidance derived from the entire 1992 PA is presented in Volume 6. Results of the 1992 uncertainty and sensitivity analyses indicate that, conditional on the modeling assumptions and the assigned parameter-value distributions, the most important parameters for which uncertainty has the potential to affect gas and brine migration from the undisturbed repository are: initial liquid saturation in the waste, anhydrite permeability, biodegradation-reaction stoichiometry, gas-generation rates for both corrosion and biodegradation under inundated conditions, and the permeability of the long-term shaft seal

  20. Treatment of Unruptured Intracranial Aneurysms and Cognitive Performance: Preliminary Results of a Prospective Clinical Trial.

    Science.gov (United States)

    Bründl, Elisabeth; Böhm, Christina; Lürding, Ralf; Schödel, Petra; Bele, Sylvia; Hochreiter, Andreas; Scheitzach, Judith; Zeman, Florian; Brawanski, Alexander; Schebesch, Karl-Michael

    2016-10-01

    Few studies have addressed the effect of treatment of unruptured intracranial aneurysm (UIA) on cognitive function. Neuropsychological assessment after UIA treatment is underreported, and prospective trials have repeatedly been demanded. In 2014, we conducted a prospective controlled study to evaluate the differences in cognitive processing caused by the treatment of anterior circulation UIAs. Thirty patients were enrolled until September 2015. Ten patients received endovascular aneurysm occlusion (EV), 10 patients were treated microsurgically (MS), and 10 patients with surgically treated degenerative lumbar spine disease (LD) served as control. All patients underwent extended standardized neuropsychological assessment before (t 1 ) and 6 weeks after treatment (t 2 ). Tests included verbal, visual, and visuospatial memory, psychomotor functioning, executive functioning, and its subdomains verbal fluency and cognitive flexibility. We statistically evaluated intragroup and intergroup changes. Intragroup comparisons and group-rate analysis showed no significant impairment in overall neuropsychological performance, either postinterventionally or postoperatively. However, the postoperative performance in cognitive processing speed, cognitive flexibility, and executive functioning was significantly worse in the MS group than in the EV (P = 0.038) and LD group (P = 0.02). Compared with the EV group, patients with MS showed significant postoperative impairment in a subtest for auditory-verbal memory (Wechsler Memory Scale, Fourth Edition, Logical Memory II; MS vs. EV P = 0.011). The MS group trended toward posttreatment impairment in subtests for verbal fluency and semantic memory (Regensburg Word Fluency Test; MS vs. EV P = 0.083) and in auditory-verbal memory (Wechsler Memory Scale, Fourth Edition, Logical Memory II; MS vs. LD P = 0.06). Our preliminary data showed no effect of anterior circulation UIA treatment on overall neuropsychological function but impaired

  1. Preliminary evaluation of rotational Vol-oxidizer for hot cell operation - 5320

    International Nuclear Information System (INIS)

    Kim, Y.H.; Lee, J.W.; Cho, Y.Z.; Ahn, D.H.; Song, K.C.

    2015-01-01

    KAERI is developing a mechanical head-end process for pyro-processing. As a piece of the processing equipment, a vol-oxidizer that can handle several tens of kg of HM/batch is under development to supply U 3 O 8 powders to an electrolytic reduction (ER) reactor. To operate a vol-oxidizer in a hot cell, the reactor should be optimized by the mechanical design, and the vol-oxidizer should have a high hull recovery rate. In addition, a vol-oxidizer for hot cell demonstrations that handles the spent fuel of high radiation virulence in a limited space should have a small size and not scatter in its outlet. In this paper, we aim at a preliminary evaluation of a rotational vol-oxidizer for hot cell operation. To evaluate the preliminary situation, we produced a theoretical equation of an optimum reactor size, and verification tests were conducted using an acryl vessel and zircaloy-4 tube according to various weights and lengths. In addition, we predicted the terminal velocity of U 3 O 8 using the terminal velocity of SiO 2 , which will determine the optimum air flux, and through an oxidation experiment, we verified the theory form to detect the existence of U 3 O 8 powder in a discharge filter. In addition, hull separation tests were conducted using a reactor and hulls with a 50 kg HM/batch for the recovery rate of the hulls. The results indicate that we obtained an appropriate air flux so as to not cause U 3 O 8 powder dispersion from using a Stokes equation and density ratio equation prior to the demonstration. The optimum flow and experimental results of the hull separation test have been applied for the design of the demonstration oxidizer, and the operation conditions of the oxidizer were produced. (authors)

  2. Effects of emotionally charged auditory stimulation on gait performance in the elderly: a preliminary study.

    Science.gov (United States)

    Rizzo, John-Ross; Raghavan, Preeti; McCrery, J R; Oh-Park, Mooyeon; Verghese, Joe

    2015-04-01

    To evaluate the effect of a novel divided attention task-walking under auditory constraints-on gait performance in older adults and to determine whether this effect was moderated by cognitive status. Validation cohort. General community. Ambulatory older adults without dementia (N=104). Not applicable. In this pilot study, we evaluated walking under auditory constraints in 104 older adults who completed 3 pairs of walking trials on a gait mat under 1 of 3 randomly assigned conditions: 1 pair without auditory stimulation and 2 pairs with emotionally charged auditory stimulation with happy or sad sounds. The mean age of subjects was 80.6±4.9 years, and 63% (n=66) were women. The mean velocity during normal walking was 97.9±20.6cm/s, and the mean cadence was 105.1±9.9 steps/min. The effect of walking under auditory constraints on gait characteristics was analyzed using a 2-factorial analysis of variance with a 1-between factor (cognitively intact and minimal cognitive impairment groups) and a 1-within factor (type of auditory stimuli). In both happy and sad auditory stimulation trials, cognitively intact older adults (n=96) showed an average increase of 2.68cm/s in gait velocity (F1.86,191.71=3.99; P=.02) and an average increase of 2.41 steps/min in cadence (F1.75,180.42=10.12; Pactivities of daily living accounted for these differences. Our results provide preliminary evidence of the differentiating effect of emotionally charged auditory stimuli on gait performance in older individuals with minimal cognitive impairment compared with those without minimal cognitive impairment. A divided attention task using emotionally charged auditory stimuli might be able to elicit compensatory improvement in gait performance in cognitively intact older individuals, but lead to decompensation in those with minimal cognitive impairment. Further investigation is needed to compare gait performance under this task to gait on other dual-task paradigms and to separately examine the

  3. LOD 1 VS. LOD 2 - Preliminary Investigations Into Differences in Mobile Rendering Performance

    Science.gov (United States)

    Ellul, C.; Altenbuchner, J.

    2013-09-01

    The increasing availability, size and detail of 3D City Model datasets has led to a challenge when rendering such data on mobile devices. Understanding the limitations to the usability of such models on these devices is particularly important given the broadening range of applications - such as pollution or noise modelling, tourism, planning, solar potential - for which these datasets and resulting visualisations can be utilized. Much 3D City Model data is created by extrusion of 2D topographic datasets, resulting in what is known as Level of Detail (LoD) 1 buildings - with flat roofs. However, in the UK the National Mapping Agency (the Ordnance Survey, OS) is now releasing test datasets to Level of Detail (LoD) 2 - i.e. including roof structures. These datasets are designed to integrate with the LoD 1 datasets provided by the OS, and provide additional detail in particular on larger buildings and in town centres. The availability of such integrated datasets at two different Levels of Detail permits investigation into the impact of the additional roof structures (and hence the display of a more realistic 3D City Model) on rendering performance on a mobile device. This paper describes preliminary work carried out to investigate this issue, for the test area of the city of Sheffield (in the UK Midlands). The data is stored in a 3D spatial database as triangles and then extracted and served as a web-based data stream which is queried by an App developed on the mobile device (using the Android environment, Java and OpenGL for graphics). Initial tests have been carried out on two dataset sizes, for the city centre and a larger area, rendering the data onto a tablet to compare results. Results of 52 seconds for rendering LoD 1 data, and 72 seconds for LoD 1 mixed with LoD 2 data, show that the impact of LoD 2 is significant.

  4. Meteosat third generation: preliminary imagery and sounding mission concepts and performances

    Science.gov (United States)

    Aminou, Donny M.; Bézy, Jean-Loup; Bensi, Paolo; Stuhlmann, Rolf; Rodriguez, Antonio

    2017-11-01

    The operational deployment of MSG-1 at the beginning of 2004, the first of a series of four Meteosat Second Generation (MSG) satellites, marks the start of a new era in Europe for the meteorological observations from the geostationary orbit. This new system shall be the backbone of the European operational meteorological services up to at least 2015. The time required for the definition and the development of new space systems as well as the approval process of such complex programs implies to plan well ahead for the future missions. EUMETSAT have initiated in 2001, with ESA support, a User Consultation Process aiming at preparing for a future operational geostationary meteorological satellite system in the post-MSG era, named Meteosat Third Generation (MTG). The first phase of the User Consultation Process was devoted to the definition and consolidation of end user requirements and priorities in the field of Nowcasting and Very Short Term Weather Forecasting (NWC), Medium/Short Range global and regional Numerical Weather Prediction (NWP), Climate and Air Composition Monitoring and to the definition of the relevant observation techniques. After an initial post-MSG mission study (2003-2004) where preliminary instrument concepts were investigated allowing in the same time to consolidate the technical requirements for the overall system study, a MTG pre-phase A study has been performed for the overall system concept, architecture and programmatic aspects during 2004-2005 time frame. This paper provides an overview of the outcome of the MTG sensor concept studies conducted in the frame of the pre-phase A. It namely focuses onto the Imaging and Sounding Missions, highlights the resulting instrument concepts, establishes the critical technologies and introduces the study steps towards the implementation of the MTG development programme.

  5. Effects of creatine supplementation on exercise performance and muscular strength in amyotrophic lateral sclerosis: preliminary results.

    Science.gov (United States)

    Mazzini, L; Balzarini, C; Colombo, R; Mora, G; Pastore, I; De Ambrogio, R; Caligari, M

    2001-10-15

    Creatine supplementation in humans has been reported to enhance power and strength both in normal subjects and in patients with various neuromuscular diseases. The purpose of this study was to examine the effects of supplementation on exercise performance and maximal voluntary isometric muscular contraction (MVIC) in Amyotrophic Lateral Sclerosis (ALS) patients. We report the results obtained in 28 patients with probable/definite ALS. In each patient we acquired the dynamometric measurement of MVIC in 10 muscle groups of upper and lower limbs and a measure of fatigue by means of an high-intensity intermittent protocol in elbow flexors and knee extensors muscles. All patients completed the protocols at the baseline and after supplementation of 20 g per day for 7 days and after supplementation of 3 g per day for 3 and 6 months. MVIC increased after 7 days of supplementation in 20 patients (70%) in knee extensors and in 15 (53%) of them also in elbow flexors. A statistically significant difference between pre and post-treatment mean values of MVIC was found both in elbow flexors (P<0.05) and knee extensors (p<0.04). The analysis of the slopes of fatigue test showed a statistically significant improvement after 7 days of supplementation in 11 patients (39%) in elbow flexors and in 9 patients (32%) also in knee extensors muscles. During the 6-month follow-up period all the examined parameters showed a linear progressive decline. In conclusion, our preliminary results have demonstrated that supplementation temporary increases maximal isometric power in ALS patients so it may be of potential benefit in situations such as high intensity activity and it can be proposed as a symptomatic treatment.

  6. Effect of alternative conceptual models in a preliminary performance assessment for the waste isolation pilot plant

    International Nuclear Information System (INIS)

    Helton, J.C.; Bean, J.E.; Berglund, J.W.; Beyeler, W.; Garner, J.W.; Iuzzolino, H.J.; Marietta, M.G.; Rudeen, D.K.; Schreiber, J.D.; Swift, P.N.; Tierney, M.S.; Vaughn, P.

    1995-01-01

    The most appropriate conceptual model for performance assessment (PA) at the waste isolation pilot plant (WIPP) is believed to include gas generation resulting from corrosion and microbial action in the repository, and a dual-porosity (matrix and fracture porosity) representation for the solute transport in the Culebra dolomite member of the Rustler formation. Under these assumptions, complementary cummulative distribution functions (CCDFs) which summarize the radionuclide releases to the accessible environment, resulting from both cutting removal and groundwater transport, fall substantially below the release limits promulgated by the US Environmental Protection Agency (EPA), with the releases being dominated by cuttings removal. To provide additional views, the following alternative conceptual models were considered as part of a preliminary PA for the WIPP: no gas generation in the repository and a dual-porosity transport model in the Culebra; gas generation in the repository and a single-porosity (fracture porosity) transport model in the Culebra; no gas generation in the repository and a single-porosity transport model in the Culebra; gas generation in the repository and a dual-porosity transport model in the Culebra, without chemical retardation; gas generation in the repository, chemical retardation in the Culebra, and extremes of climatic variation. These variations relate to groundwater transport, so do not affect the releases resulting from cuttings removal. Several of these variations substantially increase the importance of releases resulting from groundwater transport relative to releases resulting from cuttings removal. However, the total amount of releases generally remained small, with the CCDFs which summarize the releases to the accessible environment falling below the EPA release limits

  7. Gold-silica nanocomposites for the detection of human ovarian cancer cells: a preliminary study

    International Nuclear Information System (INIS)

    Mishra, Y K; Mohapatra, S; Avasthi, D K; Kabiraj, D; Lalla, N P; Pivin, J C; Sharma, Himani; Kar, Rajarshi; Singh, Neeta

    2007-01-01

    We report the structural and optical properties of Au nanoparticles embedded in a silica matrix synthesized by atom beam co-sputtering. The presence of surface plasmon resonant absorption indicates the formation of Au nanoparticles. Transmission electron microscopy (TEM) studies show the presence of Au nanoparticles with an average size ranging from ∼1.8 to 5.4 nm with narrow size distributions depending on the relative areas of Au and SiO 2 . We discuss the process of nucleation and growth of Au nanoparticles in the nanocomposite films formed by co-sputtering. The present method of nanoparticle synthesis is compared with other ion beam based techniques such as ion implantation and ion beam mixing. Preliminary experiments for the detection of human ovarian cancer cells using these Au nanoparticles are described

  8. Preliminary evaluation of optical glucose sensing in red cell concentrations using near-infrared diffuse-reflectance spectroscopy

    Science.gov (United States)

    Suzuki, Yusuke; Maruo, Katsuhiko; Zhang, Alice W.; Shimogaki, Kazushige; Ogawa, Hideto; Hirayama, Fumiya

    2012-01-01

    Bacterial contamination of blood products is one of the most frequent infectious complications of transfusion. Since glucose levels in blood supplies decrease as bacteria proliferate, it should be possible to detect the presence of bacterial contamination by measuring the glucose concentrations in the blood components. Hence this study is aimed to serve as a preliminary study for the nondestructive measurement of glucose level in transfusion blood. The glucose concentrations in red blood cell (RBC) samples were predicted using near-infrared diffuse-reflectance spectroscopy in the 1350 to 1850 nm wavelength region. Furthermore, the effects of donor, hematocrit level, and temperature variations among the RBC samples were observed. Results showed that the prediction performance of a dataset which contained samples that differed in all three parameters had a standard error of 29.3 mg/dL. Multiplicative scatter correction (MSC) preprocessing method was also found to be effective in minimizing the variations in scattering patterns created by various sample properties. The results suggest that the diffuse-reflectance spectroscopy may provide another avenue for the detection of bacterial contamination in red cell concentrations (RCC) products.

  9. Preliminary Study of the Use of Sulphonated Polyether Ether Ketone (SPEEK as Proton Exchange Membrane for Microbial Fuel Cell (MFC

    Directory of Open Access Journals (Sweden)

    Dani Permana

    2018-02-01

    Full Text Available Sulfonated polyether ether ketone (SPEEK was utilized as a proton exchange membrane (PEM in Microbial Fuel Cell (MFC. The SPEEK performance in producing electricity had been observed in MFC using wastewater and glucose as substrates. The MFC with catering and tofu wastewater produced maximum power density about 0.31 mW/m2 and 0.03 mW/m2, respectively, lower that of MFC with tapioca average power density of 39.4 W/m2 over 48 h. The power density boosted because of the presence of Saccharomyces cerevisiae as inoculum. The study using of S. cerevisiae and Acetobacter acetii, separately, were also conducted in with glucose as substrate. The MFC produced an average power densities were 7.3 and 6.4 mW/m2 for S. cerevisiae and A. acetii, respectively. The results of this study indicated that SPEEK membrane has the potential usage in MFCs and can substitute the commercial membrane, Nafion. Article History: Received: Juni 14th 2017; Received: Sept 25th 2017; Accepted: December 16th 2017; Available online How to Cite This Article: Putra, H.E., Permana, D and Djaenudin, D. (2018 Preliminary Study of the Use of Sulfonated Polyether Ether Ketone (SPEEK as Proton Exchange Membrane for Microbial Fuel Cell (MFC. International Journal of Renewable Energy Development, 7(1, 7-12. https://doi.org/10.14710/ijred.7.1.7-12

  10. Transoral robotic surgery for the base of tongue squamous cell carcinoma: a preliminary comparison between da Vinci Xi and Si.

    Science.gov (United States)

    Alessandrini, Marco; Pavone, Isabella; Micarelli, Alessandro; Caporale, Claudio

    2017-09-13

    Considering the emerging advantages related to da Vinci Xi robotic platform, the aim of this study is to compare for the first time the operative outcomes of this tool to the previous da Vinci Si during transoral robotic surgery (TORS), both performed for squamous cell carcinomas (SCC) of the base of tongue (BOT). Intra- and peri-operative outcomes of eight patients with early stage (T1-T2) of the BOT carcinoma and undergoing TORS by means of the da Vinci Xi robotic platform (Xi-TORS) are compared with the da Vinci Si group ones (Si-TORS). With respect to Si-TORS group, Xi-TORS group demonstrated a significantly shorter overall operative time, console time, and intraoperative blood loss, as well as peri-operative pain intensity and length of mean hospital stays and nasogastric tube positioning. Considering recent advantages offered by surgical robotic techniques, the da Vinci Xi Surgical System preliminary outcomes could suggest its possible future routine implementation in BOT squamous cell carcinoma procedures.

  11. DEMONSTRATION OF FUEL CELLS TO RECOVER ENERGY FROM ANAEROBIC DIGESTER GAS - PHASE I. CONCEPTUAL DESIGN, PRELIMINARY COST, AND EVALUATION STUDY

    Science.gov (United States)

    The report discusses Phase I (a conceptual design, preliminary cost, and evaluation study) of a program to demonstrate the recovery of energy from waste methane produced by anaerobic digestion of waste water treatment sludge. The fuel cell is being used for this application becau...

  12. Effects of coal-derived trace species on performance of molten carbonate fuel cells. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1992-05-01

    The Carbonate Fuel Cell is a very promising option for highly efficient generation of electricity from many fuels. If coal-gas is to be used, the interactions of coal-derived impurities on various fuel cell components need to be understood. Thus the effects on Carbonate Fuel Cell performance due to ten different coal-derived contaminants viz., NH{sub 3}, H{sub 2}S, HC{ell}, H{sub 2}Se, AsH{sub 3}, Zn, Pb, Cd, Sn, and Hg, have been studied at Energy Research Corporation. Both experimental and theoretical evaluations were performed, which have led to mechanistic insights and initial estimation of qualitative tolerance levels for each species individually and in combination with other species. The focus of this study was to investigate possible coal-gas contaminant effects on the anode side of the Carbonate Fuel Cell, using both out-of-cell thermogravimetric analysis by isothermal TGA, and fuel cell testing in bench-scale cells. Separate experiments detailing performance decay in these cells with high levels of ammonia contamination (1 vol %) and with trace levels of Cd, Hg, and Sn, have indicated that, on the whole, these elements do not affect carbonate fuel cell performance. However, some performance decay may result when a number of the other six species are present, singly or simultaneously, as contaminants in fuel gas. In all cases, tolerance levels have been estimated for each of the 10 species and preliminary models have been developed for six of them. At this stage the models are limited to isothermal, benchscale (300 cm{sup 2} size) single cells. The information obtained is expected to assist in the development of coal-gas cleanup systems, while the contaminant performance effects data will provide useful basic information for modeling fuel cell endurance in conjunction with integrated gasifier/fuel-cell systems (IGFC).

  13. Effects of coal-derived trace species on performance of molten carbonate fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    1992-05-01

    The Carbonate Fuel Cell is a very promising option for highly efficient generation of electricity from many fuels. If coal-gas is to be used, the interactions of coal-derived impurities on various fuel cell components need to be understood. Thus the effects on Carbonate Fuel Cell performance due to ten different coal-derived contaminants viz., NH{sub 3}, H{sub 2}S, HC{ell}, H{sub 2}Se, AsH{sub 3}, Zn, Pb, Cd, Sn, and Hg, have been studied at Energy Research Corporation. Both experimental and theoretical evaluations were performed, which have led to mechanistic insights and initial estimation of qualitative tolerance levels for each species individually and in combination with other species. The focus of this study was to investigate possible coal-gas contaminant effects on the anode side of the Carbonate Fuel Cell, using both out-of-cell thermogravimetric analysis by isothermal TGA, and fuel cell testing in bench-scale cells. Separate experiments detailing performance decay in these cells with high levels of ammonia contamination (1 vol %) and with trace levels of Cd, Hg, and Sn, have indicated that, on the whole, these elements do not affect carbonate fuel cell performance. However, some performance decay may result when a number of the other six species are present, singly or simultaneously, as contaminants in fuel gas. In all cases, tolerance levels have been estimated for each of the 10 species and preliminary models have been developed for six of them. At this stage the models are limited to isothermal, benchscale (300 cm{sup 2} size) single cells. The information obtained is expected to assist in the development of coal-gas cleanup systems, while the contaminant performance effects data will provide useful basic information for modeling fuel cell endurance in conjunction with integrated gasifier/fuel-cell systems (IGFC).

  14. Solid oxide electrolysis cells - Performance and durability

    Energy Technology Data Exchange (ETDEWEB)

    Hauch, A.

    2007-10-15

    In this work H2 electrode supported solid oxide cells (SOC) produced at Risoe National Laboratory, DTU, have been used for steam electrolysis. Electrolysis tests have been performed at temperatures from 650AeC to 950AeC, p(H2O)/p(H2) from 0.99/0.01 to 0.30/0.70 and current densities from -0.25 A/cm2 to -2 A/cm2. The solid oxide electrolysis cells (SOEC) have been characterised by iV curves and electrochemical impedance spectroscopy (EIS) at start and end of tests and by EIS under current load during electrolysis testing. The tested SOCs have shown the best initial electrolysis performance reported in literature to date. Area specific resistances of 0.26 Oecm2 at 850AeC and 0.17 Oecm2 at 950AeC were obtained from electrolysis iV curves. The general trend for the SOEC tests was: 1) a short-term passivation in first few hundred hours, 2) then an activation and 3) a subsequent and underlying long-term degradation. The transient phenomenon (passivation/activation) was shown to be a set-up dependent artefact caused by the albite glass sealing with a p(Si(OH)4) of 1.10-7 atm, leading to silica contamination of the triple-phase boundaries (TPBs) of the electrode. The long-term degradation for the SOECs was more pronounced than for fuel cell testing of similar cells. Long-term degradation of 2%/1000 h was obtained at 850AeC, p(H2O)/p(H2) = 0.5/0.5 and -0.5 A/cm2, whereas the degradation rate increased to 6%/1000h at 950AeC, p(H2O)/p(H2) = 0.9/0.1 and -1.0 A/cm2. Both the short-term passivation and the long-term degradation appear mainly to be related to processes in the H2 electrode. Scanning electron microscopy micrographs show that only limited changes occur in the Ni particle size distribution and these are not the main degradation mechanism for the SOECs. Micro and nano analysis using energy dispersive spectroscopy in combination with transmission electron microscopy (TEM) and scanning TEM reveals that glassy phase impurities have accumulated at the TPBs as a result of

  15. Lessons learned from the preliminary performance assessment exercise for the Vienne site strategies for investigating the granodiorite confinement capability

    International Nuclear Information System (INIS)

    Lebon, P.

    1999-01-01

    One of the three sites under study by ANDRA is located on the Poitou shoal in the Vienne Department. The granitic basement rock is overlain by a 160 m thick layer of Jurassic sediments containing two seasonally pumped aquifers. The preliminary hydrogeological model of the granitic basement assumed that regional flow is SE-NW, and circulates in the hecto-metric fractures, and that groundwater flow velocity is very low. A preliminary performance assessment exercise focusing on the geological barrier was carried out based on these assumptions and a disposal concept where radwaste is stored in separate granodiorite 'blocks' delimited by the water-bearing fractures. As regards of the granodioritic blocks, the programme goals include analysing of detailed structure, obtaining uncontaminated samples of interstitial ground water in order to determine its physicochemical properties and evaluating transport and retention parameters. (author)

  16. Effect of dietary natural extracts mixture on rabbit does reproductive performances: preliminary data.

    Directory of Open Access Journals (Sweden)

    Sara Chiapparini

    2017-05-01

    T1 and 826 ± 26.8 g T2. These preliminary data showed that at the present dosage, the natural extracts mixture is not able to affect does reproductive performance. However, further research is needed to confirm the present data and explore the mechanism of action of this natural mixture.

  17. Performance optimization of a PEM hydrogen-oxygen fuel cell

    OpenAIRE

    Maher A.R. Sadiq Al-Baghdadi

    2013-01-01

    The objective was to develop a semi-empirical model that would simulate the performance of proton exchange membrane (PEM) fuel cells without extensive calculations. A fuel cell mathematical module has been designed and constructed to determine the performance of a PEM fuel cell. The influence of some operating parameters on the performance of PEM fuel cell has been investigated using pure hydrogen on the anode side and oxygen on the cathode side. The present model can be used to investigate t...

  18. Expression, purification, crystallization and preliminary X-ray analysis of the olfactomedin domain from the sea urchin cell-adhesion protein amassin

    International Nuclear Information System (INIS)

    Hillier, Brian J.; Sundaresan, Vidyasankar; Stout, C. David; Vacquier, Victor D.

    2005-01-01

    The olfactomedin (OLF) domain from the sea urchin cell-adhesion protein amassin has been crystallized. A native data set extending to 2.7 Å has been collected using an in-house X-ray source. A family of animal proteins is emerging which contain a conserved protein motif known as an olfactomedin (OLF) domain. Novel extracellular protein–protein interactions occur through this domain. The OLF-family member amassin, from the sea urchin Strongylocentrotus purpuratus, has previously been identified to mediate a rapid cell-adhesion event resulting in a large aggregation of coelomocytes, the circulating immune cells. In this work, heterologous expression and purification of the OLF domain from amassin was carried out and initial crystallization trials were performed. A native data set has been collected, extending to 2.7 Å under preliminary cryoconditions, using an in-house generator. This work leads the way to the determination of the first structure of an OLF domain

  19. Preliminary Transcriptome Analysis of Mature Biofilm and Planktonic Cells of Salmonella Enteritidis Exposure to Acid Stress

    Directory of Open Access Journals (Sweden)

    Kun Jia

    2017-09-01

    Full Text Available Salmonella has emerged as a well-recognized food-borne pathogen, with many strains able to form biofilms and thus cause cross-contamination in food processing environments where acid-based disinfectants are widely encountered. In the present study, RNA sequencing was employed to establish complete transcriptome profiles of Salmonella Enteritidis in the forms of planktonic and biofilm-associated cells cultured in Tryptic Soytone Broth (TSB and acidic TSB (aTSB. The gene expression patterns of S. Enteritidis significantly differed between biofilm-associated and planktonic cells cultivated under the same conditions. The assembled transcriptome of S. Enteritidis in this study contained 5,442 assembled transcripts, including 3,877 differentially expressed genes (DEGs identified in biofilm and planktonic cells. These DEGs were enriched in terms such as regulation of biological process, metabolic process, macromolecular complex, binding and transferase activity, which may play crucial roles in the biofilm formation of S. Enteritidis cultivated in aTSB. Three significant pathways were observed to be enriched under acidic conditions: bacterial chemotaxis, porphyrin-chlorophyll metabolism and sulfur metabolism. In addition, 15 differentially expressed novel non-coding small RNAs (sRNAs were identified, and only one was found to be up-regulated in mature biofilms. This preliminary study of the S. Enteritidis transcriptome serves as a basis for future investigations examining the complex network systems that regulate Salmonella biofilm in acidic environments, which provide information on biofilm formation and acid stress interaction that may facilitate the development of novel disinfection procedures in the food processing industry.

  20. Preliminary Axial Flow Turbine Design and Off-Design Performance Analysis Methods for Rotary Wing Aircraft Engines. Part 1; Validation

    Science.gov (United States)

    Chen, Shu-cheng, S.

    2009-01-01

    For the preliminary design and the off-design performance analysis of axial flow turbines, a pair of intermediate level-of-fidelity computer codes, TD2-2 (design; reference 1) and AXOD (off-design; reference 2), are being evaluated for use in turbine design and performance prediction of the modern high performance aircraft engines. TD2-2 employs a streamline curvature method for design, while AXOD approaches the flow analysis with an equal radius-height domain decomposition strategy. Both methods resolve only the flows in the annulus region while modeling the impact introduced by the blade rows. The mathematical formulations and derivations involved in both methods are documented in references 3, 4 for TD2-2) and in reference 5 (for AXOD). The focus of this paper is to discuss the fundamental issues of applicability and compatibility of the two codes as a pair of companion pieces, to perform preliminary design and off-design analysis for modern aircraft engine turbines. Two validation cases for the design and the off-design prediction using TD2-2 and AXOD conducted on two existing high efficiency turbines, developed and tested in the NASA/GE Energy Efficient Engine (GE-E3) Program, the High Pressure Turbine (HPT; two stages, air cooled) and the Low Pressure Turbine (LPT; five stages, un-cooled), are provided in support of the analysis and discussion presented in this paper.

  1. Parallel local search for solving Constraint Problems on the Cell Broadband Engine (Preliminary Results

    Directory of Open Access Journals (Sweden)

    Salvator Abreu

    2009-10-01

    Full Text Available We explore the use of the Cell Broadband Engine (Cell/BE for short for combinatorial optimization applications: we present a parallel version of a constraint-based local search algorithm that has been implemented on a multiprocessor BladeCenter machine with twin Cell/BE processors (total of 16 SPUs per blade. This algorithm was chosen because it fits very well the Cell/BE architecture and requires neither shared memory nor communication between processors, while retaining a compact memory footprint. We study the performance on several large optimization benchmarks and show that this achieves mostly linear time speedups, even sometimes super-linear. This is possible because the parallel implementation might explore simultaneously different parts of the search space and therefore converge faster towards the best sub-space and thus towards a solution. Besides getting speedups, the resulting times exhibit a much smaller variance, which benefits applications where a timely reply is critical.

  2. Identification of transplanted pancreatic islet cells by radioactive Dithizone-[131I]-Histamine conjugate. Preliminary report

    International Nuclear Information System (INIS)

    Garnuszek, P.; Licinska, I.; Mazurek, A.P.; Mrozek, A.; Wardawa, A.; Fiedor, P.S.

    2000-01-01

    Background: The unique mechanism of dithizone action in the interior of the viable pancreatic islet suggests the possible development of a specific radiopharmaceutical that may have a potential clinical application in the diagnosis of the pancreatic organ allografts or islets rejection. The radiodiagnostic properties of the newly developed radioactive analogue of dithizone, i.e. Dithizone-[131I]-Histamine conjugate have been evaluated in the present study. METHODS: The four islet cells transplantation models were chosen for this purpose. The most important feature of the Dithizone-[131I]-Histamine conjugate is its possessed ability of zinc chelation. As was presented in the recent study, the conjugate stains pink-reddish the isolated pancreatic islets in vitro. Among the studied transplantation models, only the islets grafting under testis capsule enabled determination of the pancreatic islets in rats by radioactive Dithizone-[131I]-Histamine conjugate. The level of the radioactivity in the recipient testis (right) was almost two times higher compared to the controls (0.24 v. 0.13% ID/g, respectively). CONCLUSIONS: These preliminary data demonstrate the ability of the developed radioactive analogue of dithizone for in vivo identification of transplanted pancreatic islets, and suggests a potential clinical application of the radiodithizone in the diagnosis of the pancreatic islet rejection. (author)

  3. Preliminary report on the experiment performed in MARIUS reactor loaded with teledial fuel

    Energy Technology Data Exchange (ETDEWEB)

    Estiot, J C; Morier, F

    1972-06-15

    The experimental work described in this paper is part of a collaborative programme agreed between CEA and the Dragon Project. The aim of the programme is the measurement of the relative conversion ratio in a reactor loaded with Teledial fuel elements. The results will allow us to check our calculational methods and assumptions upon which the calculations are based, in the case of a teledial core, which represents a very complicated geometry, specially, due to the presence of the U238 with its resonance. The programme of experiments described in the paper have been completed. Some preliminary results are presented in the second part of this report (Part 2).

  4. Influence of Ta Content in High Purity Niobium on Cavity Performance Preliminary Results*

    CERN Document Server

    Kneisel, P

    2004-01-01

    In a previous paper* a program designed to study the influence of the residual tantalum content on the superconducting properties of pure niobium metal for RF cavities was outlined. The main rationale for this program was based on a potential cost reduction for high purity niobium, if a less strict limit on the chemical specification for Ta content, which is not significantly affecting the RRR–value, could be tolerated for high performance cavities. Four ingots with different Ta contents have been melted and transformed into sheets. In each manufacturing step the quality of the material has been monitored by employing chemical analysis, neutron activation analysis, thermal conductivity measurements and evaluation of the mechanical properties. The niobium sheets have been scanned for defects by an eddy current device. From three of the four ingots—Ta contents 100, 600 and 1,200 wppm—two single cell cavities each of the CEBAF variety have been fabricated and a series of tests on each ...

  5. Preliminary screening and identification of the peptide binding to hepatocarcinoma cell

    International Nuclear Information System (INIS)

    Zhu Xiaohua; Wu Ha

    2004-01-01

    Objective: The present study was performed to screen and isolate homing peptides that bind specifically, or preferentially, to hepatocarcinoma cells using phage display of random peptide library with the purpose of developing a new peptide which may be potentially used as target delivery carrier in the biological target diagnosis or therapy for liver cancer. Methods: A peptide 12-mer phage display library was used to screen and isolate peptide that bind to human hepatocarcinoma cell, and four rounds subtractive panning were carried out with the human hepatocarcinoma cell line HepG2 as the target. The affinities of selected phage clones to human hepatocarcinoma cell were determined with ELISA and compared with human liver cell and other tumor cells of different tissue origins respectively. In addition, the binding site in the tumor cells was observed with immunofluorescence analysis under confocal light microscopy. The amino acid sequences of phages that bind HepG2 specifically were deduced though DNA sequencing. Based on the results of DNA sequence, a 16-mer peptide (WH16) was designed and synthesized. Binding ability of the new peptide WH16 was determined with competitive inhibition test. Results: After four rounds panning, the phages that bound to and internalized in human hepatocarcinoma cell were isolated. ELISA and immunofluorescence analysis confirmed the affinity of these phages to hepatpcarcinoma cells 56.57%(17/30) of the isolated phages displayed repeated sequence FLLEPHLMDTSM, and FLEP was defined as conservative motif. Binding of the selected phage to HepG2 cells was inhibited by synthesized peptide WH16, which strongly support that cellular binding of phage is mediated though its displayed peptide and WH16 can also bind to HepG2. Conclusion: It is feasible to screen and isolate homing peptides that bind specifically, or preferentially, to hepatocarcinoma cells using phage display of random peptide libraries. The sequence of peptide that can bind to

  6. Preliminary screening and identification of the peptide binding to hepatocarcinoma cell

    Energy Technology Data Exchange (ETDEWEB)

    Xiaohua, Zhu; Ha, Wu [Department of Nuclear Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China)

    2004-07-01

    Objective: The present study was performed to screen and isolate homing peptides that bind specifically, or preferentially, to hepatocarcinoma cells using phage display of random peptide library with the purpose of developing a new peptide which may be potentially used as target delivery carrier in the biological target diagnosis or therapy for liver cancer. Methods: A peptide 12-mer phage display library was used to screen and isolate peptide that bind to human hepatocarcinoma cell, and four rounds subtractive panning were carried out with the human hepatocarcinoma cell line HepG2 as the target. The affinities of selected phage clones to human hepatocarcinoma cell were determined with ELISA and compared with human liver cell and other tumor cells of different tissue origins respectively. In addition, the binding site in the tumor cells was observed with immunofluorescence analysis under confocal light microscopy. The amino acid sequences of phages that bind HepG2 specifically were deduced though DNA sequencing. Based on the results of DNA sequence, a 16-mer peptide (WH16) was designed and synthesized. Binding ability of the new peptide WH16 was determined with competitive inhibition test. Results: After four rounds panning, the phages that bound to and internalized in human hepatocarcinoma cell were isolated. ELISA and immunofluorescence analysis confirmed the affinity of these phages to hepatpcarcinoma cells 56.57%(17/30) of the isolated phages displayed repeated sequence FLLEPHLMDTSM, and FLEP was defined as conservative motif. Binding of the selected phage to HepG2 cells was inhibited by synthesized peptide WH16, which strongly support that cellular binding of phage is mediated though its displayed peptide and WH16 can also bind to HepG2. Conclusion: It is feasible to screen and isolate homing peptides that bind specifically, or preferentially, to hepatocarcinoma cells using phage display of random peptide libraries. The sequence of peptide that can bind to

  7. Performance of a low-cost methane sensor for ambient concentration measurements in preliminary studies

    Directory of Open Access Journals (Sweden)

    W. Eugster

    2012-08-01

    Full Text Available Methane is the second most important greenhouse gas after CO2 and contributes to global warming. Its sources are not uniformly distributed across terrestrial and aquatic ecosystems, and most of the methane flux is expected to stem from hotspots which often occupy a very small fraction of the total landscape area. Continuous time-series measurements of CH4 concentrations can help identify and locate these methane hotspots. Newer, low-cost trace gas sensors such as the Figaro TGS 2600 can detect CH4 even at ambient concentrations. Hence, in this paper we tested this sensor under real-world conditions over Toolik Lake, Alaska, to determine its suitability for preliminary studies before placing more expensive and service-intensive equipment at a given locality. A reasonably good agreement with parallel measurements made using a Los Gatos Research FMA 100 methane analyzer was found after removal of the strong sensitivities for temperature and relative humidity. Correcting for this sensitivity increased the absolute accuracy required for in-depth studies, and the reproducibility between two TGS 2600 sensors run in parallel is very good. We conclude that the relative CH4 concentrations derived from such sensors are sufficient for preliminary investigations in the search of potential methane hotspots.

  8. Performance of Small Bore 60NiTi Hybrid Ball Bearings: Preliminary Life Test Results

    Science.gov (United States)

    Dellacorte, Christopher; Howard, S. Adam

    2016-01-01

    Small bore (R8 size) hybrid ball bearings made with 60NiTi races and silicon nitride balls are under development for highly corrosive aerospace applications that are also exposed to heavy static (shock) loads. The target application is the vacuum pump used inside the wastewater recycling system on the International Space Station. To verify bearing longevity, life tests are run at 2000rpm for time periods up to 5000 hours. Accelerometers with data tracking are used to monitor operation and the bearings are disassembled and inspected at intervals to assess wear. Preliminary tests show that bearings made from 60NiTi are feasible for this aerospace and potentially other industrial applications that must endure similar operating environments.

  9. The performance of Dutch photovoltaic inverters in areas with low grid voltage. A preliminary study

    International Nuclear Information System (INIS)

    Van Twisk, J.; Van der Borg, N.J.C.M.; Groeman, J.F.

    2000-08-01

    An important component of grid-connected photovoltaic (PV) systems is the inverter. The inverter must be suitable for the expected characteristics of the input of the photovoltaic panels and for the expected characteristics of the output of the electricity network. The characteristics of the electric grid in potential markets for Dutch inverter manufacturers can differ from the characteristics of Dutch electric grids. A preliminary study has been carried out to determine the characteristics of relevant power distribution systems and the expected effects of those networks on PV-inverters. It is concluded that the following characteristics need further study: voltage level (nominal voltage and long-lasting deviations of that level); transient overvoltages, harmonic components in the voltage, and direct current component. 5 refs

  10. Operating performance and environmental and safety risks: A preliminary comparison of majors and independents

    International Nuclear Information System (INIS)

    Pulsipher, A.G.; Iledare, W.O.; Baumann, R.H.; Mesyanzhinov, D.

    1995-01-01

    The objective is to compare the safety and environmental records of oil and gas companies operating on the OCS in the Gulf of Mexico over the past decade. The reason for doing so is to help inform public sector policy-makers and private sector decision-makers about the potential safety and environmental risks associated with the expected increased presence of smaller independents in the domestic oil and gas industry in general and on the federal OCS in particular. The preliminary conclusion is that although independents have had a modestly high incidence of fires and explosions than the majors, the difference is not significant statistically and is largely attributable to a few ''bad actors'' rather than demonstrably poorer practice by the group as a whole

  11. Preliminary investigation of stereotactic body radiation therapy for medically inoperable stage I/II non-small cell lung cancer

    International Nuclear Information System (INIS)

    Guo Jindong; Lu Changxing; Wang Jiaming; Liu Jun; Li Hongxuan; Wang Changlu; Gao Lanting; Zhao Lei

    2011-01-01

    Objective: To evaluate the therapeutic efficacy and treatment-related toxicity of stereotactic body radiation therapy (SBRT) in patients with medically inoperable stage I/II non-small cell lung cancer (NSCLC). Methods: SBRT was applied to 30 patients, including clinically staged T 1 , T 2 (≤5 cm) or T 3 (chest wall primary tumors only), N 0 , M 0 ,biopsy-confirmed NSCLC. All patients were precluded from lobotomy because of physical condition or comorbidity. No patients developed tumors of any T-stage in the proximal zone. SBRT was performed with the total dose of 50 Gy to 70 Gy in 10 - 11 fractions during 12 - 15 days. prescription line was set onthe edge of the PTV. Results: The follow-up rate was 100%. The number of patients who completed the 1-, and 2-year follow-up were 15, and 10, respectively. All 30 patients completed therapy as planned. The complete response (CR), partial response (PR) and stable disease (SD) rates were 37%, 53% and 3%, respectively. With a median follow-up of 16 months (range, 4-36 months), Kaplan-Meier local control at 2 years was 94%. The 2-year overall survival was 84% and the 2-year cancer specific survival was 90%. Seven patients(23%) developed Grade 2 pneumonitis, no grade > 2 acute or late lung toxicity was observed. No one developed chest wall pain. Conclusions: It is feasible to deliver 50 Gy to 70 Gy of SBRT in 10 - 11 fractions for medically inoperable patients with stage I / II NSCLC. It was associated with low incidence of toxicities and provided sustained local tumor control.The preliminary investigation indicated the cancer specific survival probability of SBRT was high. It is necessary to perform similar investigation in a larger number of patients with long-term follow-up. (authors)

  12. What Happens Inside a Fuel Cell? Developing an Experimental Functional Map of Fuel Cell Performance

    KAUST Repository

    Brett, Daniel J. L.; Kucernak, Anthony R.; Aguiar, Patricia; Atkins, Stephen C.; Brandon, Nigel P.; Clague, Ralph; Cohen, Lesley F.; Hinds, Gareth; Kalyvas, Christos; Offer, Gregory J.; Ladewig, Bradley; Maher, Robert; Marquis, Andrew; Shearing, Paul; Vasileiadis, Nikos; Vesovic, Velisa

    2010-01-01

    Fuel cell performance is determined by the complex interplay of mass transport, energy transfer and electrochemical processes. The convolution of these processes leads to spatial heterogeneity in the way that fuel cells perform, particularly due

  13. Preliminary performance analysis of exponential experimental system for the determination of neutron effective multiplication factor of PWR spent fuel

    International Nuclear Information System (INIS)

    Shin, Heesung; Lee, Sang-Yun; Ro, Seung-Gy; Seo, Gi-Seok; Kim, Ho-Dong

    2002-01-01

    An exponential experiment system which is composed of neutron detector, signal analysis system and neutron source, 10 mCi Cf-252 has been installed in the storage pool of PIEF at KAERI in order to experimentally determining neutron effective multiplication factors of PWR spent fuel assemblies. Preliminary functional characteristic tests of the experimental system are performed for C15, J14 and J44 assemblies loaded in the pool. As a result of preliminary tests, the average neutron counts obtained for 3 minutes in the plateau of the C15, J14 and J44 assemblies are about 1900, 3800 and 3200, respectively. A dip of the neutron flux density distribution is noticed in the spacer grid position. Neutron counts at those positions appear to be reduced to about 70 % in comparison to the fuel position. The measured axial neutron distribution shapes are compared with the result for the P14 assembly and Cs-137 gamma scanning data performed in KAERI. It is revealed that the spacer grid position measured is consistent with the design specifications within a 2.3 % error. The exponential decay constants for the C15 assembly were determined to be 0.152 and 0.165 for detector and source scanning, respectively. (author)

  14. Emergency CT brain: preliminary interpretation with a tablet device: image quality and diagnostic performance of the Apple iPad.

    LENUS (Irish Health Repository)

    Mc Laughlin, Patrick

    2012-04-01

    Tablet devices have recently been used in radiological image interpretation because they have a display resolution comparable to desktop LCD monitors. We identified a need to examine tablet display performance prior to their use in preliminary interpretation of radiological images. We compared the spatial and contrast resolution of a commercially available tablet display with a diagnostic grade 2 megapixel monochrome LCD using a contrast detail phantom. We also recorded reporting discrepancies, using the ACR RADPEER system, between preliminary interpretation of 100 emergency CT brain examinations on the tablet display and formal review on a diagnostic LCD. The iPad display performed inferiorly to the diagnostic monochrome display without the ability to zoom. When the software zoom function was enabled on the tablet device, comparable contrast detail phantom scores of 163 vs 165 points were achieved. No reporting discrepancies were encountered during the interpretation of 43 normal examinations and five cases of acute intracranial hemorrhage. There were seven RADPEER2 (understandable) misses when using the iPad display and 12 with the diagnostic LCD. Use of software zoom in the tablet device improved its contrast detail phantom score. The tablet allowed satisfactory identification of acute CT brain findings, but additional research will be required to examine the cause of "understandable" reporting discrepancies that occur when using tablet devices.

  15. Exponential Decay Nonlinear Regression Analysis of Patient Survival Curves: Preliminary Assessment in Non-Small Cell Lung Cancer

    Science.gov (United States)

    Stewart, David J.; Behrens, Carmen; Roth, Jack; Wistuba, Ignacio I.

    2010-01-01

    Background For processes that follow first order kinetics, exponential decay nonlinear regression analysis (EDNRA) may delineate curve characteristics and suggest processes affecting curve shape. We conducted a preliminary feasibility assessment of EDNRA of patient survival curves. Methods EDNRA was performed on Kaplan-Meier overall survival (OS) and time-to-relapse (TTR) curves for 323 patients with resected NSCLC and on OS and progression-free survival (PFS) curves from selected publications. Results and Conclusions In our resected patients, TTR curves were triphasic with a “cured” fraction of 60.7% (half-life [t1/2] >100,000 months), a rapidly-relapsing group (7.4%, t1/2=5.9 months) and a slowly-relapsing group (31.9%, t1/2=23.6 months). OS was uniphasic (t1/2=74.3 months), suggesting an impact of co-morbidities; hence, tumor molecular characteristics would more likely predict TTR than OS. Of 172 published curves analyzed, 72 (42%) were uniphasic, 92 (53%) were biphasic, 8 (5%) were triphasic. With first-line chemotherapy in advanced NSCLC, 87.5% of curves from 2-3 drug regimens were uniphasic vs only 20% of those with best supportive care or 1 drug (p<0.001). 54% of curves from 2-3 drug regimens had convex rapid-decay phases vs 0% with fewer agents (p<0.001). Curve convexities suggest that discontinuing chemotherapy after 3-6 cycles “synchronizes” patient progression and death. With postoperative adjuvant chemotherapy, the PFS rapid-decay phase accounted for a smaller proportion of the population than in controls (p=0.02) with no significant difference in rapid-decay t1/2, suggesting adjuvant chemotherapy may move a subpopulation of patients with sensitive tumors from the relapsing group to the cured group, with minimal impact on time to relapse for a larger group of patients with resistant tumors. In untreated patients, the proportion of patients in the rapid-decay phase increased (p=0.04) while rapid-decay t1/2 decreased (p=0.0004) with increasing

  16. Preliminary safety analysis report for the Auxiliary Hot Cell Facility, Sandia National Laboratories, Albuquerque, New Mexico

    International Nuclear Information System (INIS)

    OSCAR, DEBBY S.; WALKER, SHARON ANN; HUNTER, REGINA LEE; WALKER, CHERYL A.

    1999-01-01

    The Auxiliary Hot Cell Facility (AHCF) at Sandia National Laboratories, New Mexico (SNL/NM) will be a Hazard Category 3 nuclear facility used to characterize, treat, and repackage radioactive and mixed material and waste for reuse, recycling, or ultimate disposal. A significant upgrade to a previous facility, the Temporary Hot Cell, will be implemented to perform this mission. The following major features will be added: a permanent shield wall; eight floor silos; new roof portals in the hot-cell roof; an upgraded ventilation system; and upgraded hot-cell jib crane; and video cameras to record operations and facilitate remote-handled operations. No safety-class systems, structures, and components will be present in the AHCF. There will be five safety-significant SSCs: hot cell structure, permanent shield wall, shield plugs, ventilation system, and HEPA filters. The type and quantity of radionuclides that could be located in the AHCF are defined primarily by SNL/NM's legacy materials, which include radioactive, transuranic, and mixed waste. The risk to the public or the environment presented by the AHCF is minor due to the inventory limitations of the Hazard Category 3 classification. Potential doses at the exclusion boundary are well below the evaluation guidelines of 25 rem. Potential for worker exposure is limited by the passive design features incorporated in the AHCF and by SNL's radiation protection program. There is no potential for exposure of the public to chemical hazards above the Emergency Response Protection Guidelines Level 2

  17. Preliminary safety analysis report for the Auxiliary Hot Cell Facility, Sandia National Laboratories, Albuquerque, New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    OSCAR,DEBBY S.; WALKER,SHARON ANN; HUNTER,REGINA LEE; WALKER,CHERYL A.

    1999-12-01

    The Auxiliary Hot Cell Facility (AHCF) at Sandia National Laboratories, New Mexico (SNL/NM) will be a Hazard Category 3 nuclear facility used to characterize, treat, and repackage radioactive and mixed material and waste for reuse, recycling, or ultimate disposal. A significant upgrade to a previous facility, the Temporary Hot Cell, will be implemented to perform this mission. The following major features will be added: a permanent shield wall; eight floor silos; new roof portals in the hot-cell roof; an upgraded ventilation system; and upgraded hot-cell jib crane; and video cameras to record operations and facilitate remote-handled operations. No safety-class systems, structures, and components will be present in the AHCF. There will be five safety-significant SSCs: hot cell structure, permanent shield wall, shield plugs, ventilation system, and HEPA filters. The type and quantity of radionuclides that could be located in the AHCF are defined primarily by SNL/NM's legacy materials, which include radioactive, transuranic, and mixed waste. The risk to the public or the environment presented by the AHCF is minor due to the inventory limitations of the Hazard Category 3 classification. Potential doses at the exclusion boundary are well below the evaluation guidelines of 25 rem. Potential for worker exposure is limited by the passive design features incorporated in the AHCF and by SNL's radiation protection program. There is no potential for exposure of the public to chemical hazards above the Emergency Response Protection Guidelines Level 2.

  18. Fort Hood Solar Total Energy Project. Volume II. Preliminary design. Part 2. System performance and supporting studies. Final report

    Energy Technology Data Exchange (ETDEWEB)

    None,

    1979-01-01

    The preliminary design developed for the Solar Total Energy System to be installed at Fort Hood, Texas, is presented. System performance analysis and evaluation are described. Feedback of completed performance analyses on current system design and operating philosophy is discussed. The basic computer simulation techniques and assumptions are described and the resulting energy displacement analysis is presented. Supporting technical studies are presented. These include health and safety and reliability assessments; solar collector component evaluation; weather analysis; and a review of selected trade studies which address significant design alternatives. Additional supporting studies which are generally specific to the installation site are reported. These include solar availability analysis; energy load measurements; environmental impact assessment; life cycle cost and economic analysis; heat transfer fluid testing; meteorological/solar station planning; and information dissemination. (WHK)

  19. Performance improvement of silicon solar cells by nanoporous silicon coating

    Directory of Open Access Journals (Sweden)

    Dzhafarov T. D.

    2012-04-01

    Full Text Available In the present paper the method is shown to improve the photovoltaic parameters of screen-printed silicon solar cells by nanoporous silicon film formation on the frontal surface of the cell using the electrochemical etching. The possible mechanisms responsible for observed improvement of silicon solar cell performance are discussed.

  20. Preliminary model and validation of molten carbonate fuel cell kinetics under sulphur poisoning

    Science.gov (United States)

    Audasso, E.; Nam, S.; Arato, E.; Bosio, B.

    2017-06-01

    MCFC represents an effective technology to deal with CO2 capture and relative applications. If used for these purposes, due to the working conditions and the possible feeding, MCFC must cope with a different number of poisoning gases such as sulphur compounds. In literature, different works deal with the development of kinetic models to describe MCFC performance to help both industrial applications and laboratory simulations. However, in literature attempts to realize a proper model able to consider the effects of poisoning compounds are scarce. The first aim of the present work is to provide a semi-empirical kinetic formulation capable to take into account the effects that sulphur compounds (in particular SO2) have on the MCFC performance. The second aim is to provide a practical example of how to effectively include the poisoning effects in kinetic models to simulate fuel cells performances. To test the reliability of the proposed approach, the obtained formulation is implemented in the kinetic core of the SIMFC (SIMulation of Fuel Cells) code, an MCFC 3D model realized by the Process Engineering Research Team (PERT) of the University of Genova. Validation is performed through data collected at the Korea Institute of Science and Technology in Seoul.

  1. Preliminary performance and operating results from the integrated dry NOx/SO2 emissions control system

    International Nuclear Information System (INIS)

    Hunt, T.; Schott, G.; Smith, R.; Muzio, L.; Jones, D.; Mali E.; Arrigoni, T.

    1993-01-01

    The Integrated Dry NO x /SO 2 Emissions Control System was installed at Public Service Company of Colorado's Arapaho 4 generating station in 1992 in cooperation with the U.S. Department of Energy (DOE) and and the Electric Power Research Institute (EPRI). This full scale 100 MWe demonstration combines low-NO x burners, overfire air, and selective noncatalytic reduction (SNCR) for NO x control and dry sorbent injection with humidification for SO 2 control. Operation and testing of the Integrated Dry NO x /SO 2 Emissions Control System began in August 1992 and will continue through mid 1994. Preliminary results of the NO x control technologies show that the original system goal of 70% NO x removal has been easily met and that NO x removals of up to 80% are possible at full load with the combustion and SNCR systems. Testing of the dry sorbent injection system with low sulfur coal began in April 1993 using a calcium-based reagent. A maximum SO 2 removal of 40% has been achieved with duct injection of commercial calcium hydroxide and humidification to a 25 degrees F approach to saturation. Sodium-based dry sorbent injection is expected to achieved up to a 70% SO 2 reduction

  2. Preliminary analysis of engineered barrieer performances in geological disposal of high level waste

    International Nuclear Information System (INIS)

    Ohe, Toshiaki; Maki, Yasuo; Tanaka, Hiroshi; Kawanishi, Motoi.

    1988-01-01

    This report represents preliminary results of safety analysis of a engineered barrier system in geological disposal of high level radioactive waste. Three well-known computer codes; ORIGEN 2, TRUMP, and SWIFT were used in the simulation. Main conceptual design of the repository was almost identical to that of SKB in Sweden and NAGRA in Switzerland; the engineered barrier conasists glass solidified waste, steel overpack, and compacted bentonite. Two different underground formations are considered; granite and neogene sedimentary rock, which are typically found in Japan. We first determined the repository configuration, particularly the space between disposal pitts. The ORIGEN 2 was used to estimate heat generation in the waste glass reprocessed at 4 years after removal from PWR. Then, temperature distribution was calculated by the TRUMP. The results of two or three dimensional calculation indicated that the pit interval should be kept more than 5 m in the case of granite formation at 500 m depth, according to the temperature criteria in the bentonite layer ( 90 Sr, 241 Am, 239 Pu, and 237 Np were chosen in one or two dimensional calculations. For both cases of steady release and instanteneous release, the maximum concentration in the pore water at the boundary between bentonite and surrounding rock had the following order; 237 Np> 239 Pu> 90 Sr> 241 Am. Sensitivity analysis showed that the order mainly due to the different adsorption characteristics of the nuclides in bentonite layer. (author)

  3. Acrylic acid grafted PDMS preliminary activated by Ar{sup +}beam plasma and cell observation

    Energy Technology Data Exchange (ETDEWEB)

    Kostadinova, A.; Zaekov, N. [Institute of Biophysics, BAS, Sofia (Bulgaria); Keranov, I. [Department of Polymer Engineering, University of Chemical Technology and Metallurgy (UCTM), Sofia (Bulgaria)

    2007-07-01

    Plasma based Ar{sup +} beam performed in RF (13.56 MHz) low-pressure (200 mTorr) glow discharge (at 100 W, 1200 W and 2500 W) with a serial capacitance was employed for surface modification of poly(dimethylsiloxane) (PDMS) aimed at improvement of its interactions with living cells. The presence of a serial capacitance ensures arise of an ion-flow inside the plasma volume directed toward the treated sample and the vary of the discharge power ensures varied density of the ion-flow The initial adhesion of human fibroblast cells was studied on the described above plasma based Ar{sup +}beam modified and acrylic acid (AA) grafted or not fibronectin (FN) pre-coated or ba resurfaces. The cell response seem sto be related with the peculiar structure and wettability of the modified PDMS surface layer after plasma based Ar{sup +} beam treatment followed or not by AA grafting. Key words: Biomaterials; Surface treatment of PDMS; Plasma based Ar{sup +} beam; Acrylic acid grafting; Fibroblast cells.

  4. Theoretical performance of hydrogen-bromine rechargeable SPE fuel cell

    Science.gov (United States)

    Savinell, Robert F.; Fritts, S. D.

    1987-01-01

    A mathematical model was formulated to describe the performance of a hydrogen-bromine fuel cell. Porous electrode theory was applied to the carbon felt flow-by electrode and was coupled to theory describing the solid polymer electrolyte (SPE) system. Parametric studies using the numerical solution to this model were performed to determine the effect of kinetic, mass transfer, and design parameters on the performance of the fuel cell. The results indicate that the cell performance is most sensitive to the transport properties of the SPE membrane. The model was also shown to be a useful tool for scale-up studies.

  5. Performance characterization of solid oxide cells under high pressure

    DEFF Research Database (Denmark)

    Sun, Xiufu; Bonaccorso, Alfredo Damiano; Graves, Christopher R.

    2014-01-01

    in both fuel cell mode and electrolysis mode. In electrolysis mode at low current density, the performance improvement was counteracted by the increase in open circuit voltage, but it has to be born in mind that the pressurised gas contains higher molar free energy. Operating at high current density...... hydrocarbon fuels, which is normally performed at high pressure to achieve a high yield. Operation of SOECs at elevated pressure will therefore facilitate integration with the downstream fuel synthesis and is furthermore advantageous as it increases the cell performance. In this work, recent pressurised test...... results of a planar Ni-YSZ (YSZ: Yttria stabilized Zirconia) supported solid oxide cell are presented. The test was performed at 800 °C at pressures up to 15 bar. A comparison of the electrochemical performance of the cell at 1 and 3 bar shows a significant and equal performance gain at higher pressure...

  6. Relationships between Handwriting Performance and Organizational Abilities among Children with and without Dysgraphia: A Preliminary Study

    Science.gov (United States)

    Rosenblum, Sara; Aloni, Tsipi; Josman, Naomi

    2010-01-01

    Organizational ability constitutes one executive function (EF) component essential for common everyday performance. The study aim was to explore the relationship between handwriting performance and organizational ability in school-aged children. Participants were 58 males, aged 7-8 years, 30 with dysgraphia and 28 with proficient handwriting.…

  7. Effect of compressive force on PEM fuel cell performance

    Science.gov (United States)

    MacDonald, Colin Stephen

    Polymer electrolyte membrane (PEM) fuel cells possess the potential, as a zero-emission power source, to replace the internal combustion engine as the primary option for transportation applications. Though there are a number of obstacles to vast PEM fuel cell commercialization, such as high cost and limited durability, there has been significant progress in the field to achieve this goal. Experimental testing and analysis of fuel cell performance has been an important tool in this advancement. Experimental studies of the PEM fuel cell not only identify unfiltered performance response to manipulation of variables, but also aid in the advancement of fuel cell modelling, by allowing for validation of computational schemes. Compressive force used to contain a fuel cell assembly can play a significant role in how effectively the cell functions, the most obvious example being to ensure proper sealing within the cell. Compression can have a considerable impact on cell performance beyond the sealing aspects. The force can manipulate the ability to deliver reactants and the electrochemical functions of the cell, by altering the layers in the cell susceptible to this force. For these reasons an experimental study was undertaken, presented in this thesis, with specific focus placed on cell compression; in order to study its effect on reactant flow fields and performance response. The goal of the thesis was to develop a consistent and accurate general test procedure for the experimental analysis of a PEM fuel cell in order to analyse the effects of compression on performance. The factors potentially affecting cell performance, which were a function of compression, were identified as: (1) Sealing and surface contact; (2) Pressure drop across the flow channel; (3) Porosity of the GDL. Each factor was analysed independently in order to determine the individual contribution to changes in performance. An optimal degree of compression was identified for the cell configuration in

  8. Performance Anxiety at English PBL Groups Among Taiwanese Medical Students: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Cheng-Sheng Chen

    2008-03-01

    Full Text Available Students' performance anxiety can impact negatively on the effectiveness of medical education reform, including performance in problem-based learning (PBL and in using English in discussion. This study aimed to investigate the nature of performance anxiety among Taiwanese medical students in an English-language PBL group. Eighteen Taiwanese, one American and four Asian medical students who were attending an international PBL workshop were enrolled. A questionnaire seeking demographic data and experience in use of PBL and eight questions evaluating performance anxiety were administered. The performance anxiety of Taiwanese medical students was compared to that of the Asians and the one American. Frequencies of each performance anxiety were calculated. The results suggested that the Taiwanese students showed more anxiety than the one student from the United States, but less than other Asian students. The acts of giving a report, being the center of attention, and talking in the PBL group were the most common situations related to anxiety in PBL groups. Using English and working in a new PBL environment are possible sources of anxiety. The presence of anxiety among the Taiwanese medical students in English PBL groups implies the necessity for developing an effective strategy to deal with students' performance anxiety.

  9. The impact of manufacturing complexity drivers on performance-a preliminary study

    Science.gov (United States)

    Huah Leang, Suh; Mahmood, Wan Hasrulnizzam Wan; Rahman, Muhamad Arfauz A.

    2018-03-01

    Manufacturing systems, in pursuit of cost, time and flexibility optimisation are becoming more and more complex, exhibiting a dynamic and nonlinear behaviour. Unpredictability is a distinct characteristic of such behaviour and effects production planning significantly. Therefore, this study was undertaken to investigate the priority level and current achievement of manufacturing performance in Malaysia’s manufacturing industry and the complexity drivers on manufacturing productivity performance. The results showed that Malaysia’s manufacturing industry prioritised product quality and they managed to achieve a good on time delivery performance. However, for other manufacturing performance, there was a difference where the current achievement of manufacturing performances in Malaysia’s manufacturing industry is slightly lower than the priority given to them. The strong correlation of significant value for priority status was observed between efficient production levelling (finished goods) and finish product management while the strong correlation of significant value for current achievement was minimised the number of workstation and factory transportation system. This indicates that complexity drivers have an impact towards manufacturing performance. Consequently, it is necessary to identify complexity drivers to achieve well manufacturing performance.

  10. Development and validation of trauma surgical skills metrics: Preliminary assessment of performance after training.

    Science.gov (United States)

    Shackelford, Stacy; Garofalo, Evan; Shalin, Valerie; Pugh, Kristy; Chen, Hegang; Pasley, Jason; Sarani, Babak; Henry, Sharon; Bowyer, Mark; Mackenzie, Colin F

    2015-07-01

    Maintaining trauma-specific surgical skills is an ongoing challenge for surgical training programs. An objective assessment of surgical skills is needed. We hypothesized that a validated surgical performance assessment tool could detect differences following a training intervention. We developed surgical performance assessment metrics based on discussion with expert trauma surgeons, video review of 10 experts and 10 novice surgeons performing three vascular exposure procedures and lower extremity fasciotomy on cadavers, and validated the metrics with interrater reliability testing by five reviewers blinded to level of expertise and a consensus conference. We tested these performance metrics in 12 surgical residents (Year 3-7) before and 2 weeks after vascular exposure skills training in the Advanced Surgical Skills for Exposure in Trauma (ASSET) course. Performance was assessed in three areas as follows: knowledge (anatomic, management), procedure steps, and technical skills. Time to completion of procedures was recorded, and these metrics were combined into a single performance score, the Trauma Readiness Index (TRI). Wilcoxon matched-pairs signed-ranks test compared pretraining/posttraining effects. Mean time to complete procedures decreased by 4.3 minutes (from 13.4 minutes to 9.1 minutes). The performance component most improved by the 1-day skills training was procedure steps, completion of which increased by 21%. Technical skill scores improved by 12%. Overall knowledge improved by 3%, with 18% improvement in anatomic knowledge. TRI increased significantly from 50% to 64% with ASSET training. Interrater reliability of the surgical performance assessment metrics was validated with single intraclass correlation coefficient of 0.7 to 0.98. A trauma-relevant surgical performance assessment detected improvements in specific procedure steps and anatomic knowledge taught during a 1-day course, quantified by the TRI. ASSET training reduced time to complete vascular

  11. Performance validation of commercially available mobile waste-assay systems: Preliminary report

    Energy Technology Data Exchange (ETDEWEB)

    Schanfein, M.; Bonner, C.; Maez, R. [Los Alamos National Lab., NM (United States)] [and others

    1997-11-01

    Prior to disposal, nuclear waste must be accurately characterized to identify and quantify the radioactive content to reduce the radioactive hazard to the public. Validation of the waste-assay systems` performance is critical for establishing the credibility of the assay results for storage and disposal purposes. Canberra Nuclear has evaluated regulations worldwide and identified standard, modular, neutron- and gamma-waste-assay systems that can be used to characterize a large portion of existing and newly generated transuranic (TRU) and low-level waste. Before making claims of guaranteeing any system`s performance for specific waste types, the standardized systems` performance be evaluated. 7 figs., 11 tabs.

  12. Performance validation of commercially available mobile waste-assay systems: Preliminary report

    International Nuclear Information System (INIS)

    Schanfein, M.; Bonner, C.; Maez, R.

    1997-01-01

    Prior to disposal, nuclear waste must be accurately characterized to identify and quantify the radioactive content to reduce the radioactive hazard to the public. Validation of the waste-assay systems' performance is critical for establishing the credibility of the assay results for storage and disposal purposes. Canberra Nuclear has evaluated regulations worldwide and identified standard, modular, neutron- and gamma-waste-assay systems that can be used to characterize a large portion of existing and newly generated transuranic (TRU) and low-level waste. Before making claims of guaranteeing any system's performance for specific waste types, the standardized systems' performance be evaluated. 7 figs., 11 tabs

  13. Performance of flash ADCs in the 100 MHz range: I. Test bench and preliminary results

    International Nuclear Information System (INIS)

    Crawley, H.B.; McKay, R.; Meyer, W.T.; Rosenberg, E.I.; Thomas, W.D.

    1990-01-01

    We describe a systematic study of the performance of commercially available Flash ADCs in the 100 Megasample per second range, which might be suitable for use in the Superconducting Super Collider. Performance characteristics are measured using a CAMAC based test bench which is described. Among the FADC performance characteristics reported are linearity, differential linearity and the effective number of bits. This paper is the first in a series of reports to be presented within the next year as our tests continue. 6 refs., 2 figs., 1 tab

  14. Stem Cell Ophthalmology Treatment Study (SCOTS for retinal and optic nerve diseases: a preliminary report

    Directory of Open Access Journals (Sweden)

    Jeffrey N Weiss

    2015-01-01

    Full Text Available In this report, we present the results of a single patient with optic neuropathy treated within the Stem Cell Ophthalmology Treatment Study (SCOTS. SCOTS is an Institutional Review Board approved clinical trial and is the largest ophthalmology stem cell study registered at the National Institutes of Health to date- www.clinicaltrials.gov Identifier NCT 01920867. SCOTS utilizes autologous bone marrow-derived stem cells in the treatment of optic nerve and retinal diseases. Pre- and post-treatment comprehensive eye exams were independently performed at the Wilmer Eye Institute at the Johns Hopkins Hospital, USA. A 27 year old female patient had lost vision approximately 5 years prior to enrollment in SCOTS. Pre-treatment best-corrected visual acuity at the Wilmer Eye Institute was 20/800 Right Eye (OD and 20/4,000 Left Eye (OS. Four months following treatment in SCOTS, the central visual acuity had improved to 20/100 OD and 20/40 OS.

  15. Preliminary Finding from a New Device for Monitoring Performance and Environmental Factors in the Field

    National Research Council Canada - National Science Library

    Lieberman, Harris

    2000-01-01

    .... This paper will introduce a new device, the U.S. Army Research Institute of Environmental Medicine vigilance monitor, which was developed for assessment of human performance in an automated, continuous manner in the field...

  16. Performance optimization of a PEM hydrogen-oxygen fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Sadiq Al-Baghdadi, Maher A.R. [Fuel Cell Research Center, International Energy and Environment Foundation, Al-Najaf, P.O.Box 39 (Iraq)

    2013-07-01

    The objective was to develop a semi-empirical model that would simulate the performance of proton exchange membrane (PEM) fuel cells without extensive calculations. A fuel cell mathematical module has been designed and constructed to determine the performance of a PEM fuel cell. The influence of some operating parameters on the performance of PEM fuel cell has been investigated using pure hydrogen on the anode side and oxygen on the cathode side. The present model can be used to investigate the influence of process variables for design optimization of fuel cells, stacks, and complete fuel cell power system. The possible mechanisms of the parameter effects and their interrelationships are discussed. In order to assess the validity of the developed model a real PEM fuel cell system has been used to generate experimental data. The comparison shows good agreements between the modelling results and the experimental data. The model is shown a very useful for estimating the performance of PEM fuel cell stacks and optimization of fuel cell system integration and operation.

  17. An appraisal of the 1992 preliminary performance assessment for the Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    Lee, W.W.L.; Chaturvedi, L.; Silva, M.K.; Weiner, R.; Neill, R.H.

    1994-09-01

    The purpose of the New Mexico Environmental Evaluation Group is to conduct an independent technical evaluation of the Waste Isolation Pilot Plant (WIPP) Project to ensure the protection of the public health and safety and the environment. The WIPP Project, located in southeastern New Mexico, is being constructed as a repository for the disposal of transuranic (TRU) radioactive wastes generated by the national defense programs. The Environmental Evaluation Group (EEG) has reviewed the WIPP 1992 Performance Assessment (Sandia WIPP Performance Assessment Department, 1992). Although this performance assessment was released after the October 1992 passage of the WIPP Land Withdrawal Act (PL 102-579), the work preceded the Act. For individual and ground-water protection, calculations have been done for 1000 years post closure, whereas the US Environmental Protection Agency's Standards (40 CFR 191) issued in 1993 require calculations for 10,000 years. The 1992 Performance Assessment continues to assimilate improved understanding of the geology and hydrogeology of the site, and evolving conceptual models of natural barriers. Progress has been made towards assessing WIPP's compliance with the US Environmental Protection Agency's Standards (40 CFR 191). The 1992 Performance Assessment has addressed several items of major concern to EEG, outlined in the July 1992 review of the 1991 performance assessment (Neill et al., 1992). In particular, the authors are pleased that some key results in this performance assessment deal with sensitivity of the calculated complementary cumulative distribution functions (CCDF) to alterative conceptual models proposed by EEG -- that flow in the Culebra be treated as single-porosity fracture-flow; with no sorption retardation unless substantiated by experimental data

  18. Morningness-eveningness is not associated with academic performance in the afternoon school shift: Preliminary findings.

    Science.gov (United States)

    Arrona-Palacios, Arturo; Díaz-Morales, Juan F

    2017-11-01

    The effect of morningness-eveningness, sleep habits, and intelligence on academic performance has been studied in a fixed morning school shift. However, no studies have analysed these variables in an afternoon school shift and tested whether morningness-eveningness is related to academic performance beyond sleep habits and intelligence effects. The psychometric properties of the Morningness-Eveningness Scale for Children (MESC) were analysed. Additionally, academic performance, sex, intelligence, sleep habits, and morningness-eveningness relationship in a morning and afternoon school shift were compared. The sample consisted of 400 students at a secondary public school in Reynosa, Tamaulipas, in north-eastern Mexico (195 boys and 205 girls; mean ± SD: 13.85 ± 0.70 years old) attending a double-shift school system: 200 from the morning shift (99 boys and 101 girls) and 200 from the afternoon shift (96 boys and 104 girls). The students completed the MESC as a measure of morningness-eveningness, a sleep habits survey, a test of academic performance, and the inductive reasoning subtest (R) of the Primary Mental Abilities battery. Adolescents in the two school shifts did not differ in academic performance and intelligence. In the afternoon shift, adolescents slept longer, reported less sleep deficit and social jet lag, and were more oriented to eveningness than adolescents in the morning shift. Sex (girls), sleep length, inductive reasoning, and morningness were associated with academic performance in the morning shift but only sex and intelligence in the afternoon shift. The role of morningness-eveningness in academic performance in the afternoon shift is examined. © 2017 The British Psychological Society.

  19. Performance analysis of a potassium-base AMTEC cell

    International Nuclear Information System (INIS)

    Huang, C.; Hendricks, T.J.; Hunt, T.K.

    1998-01-01

    Sodium-BASE Alkali-Metal-Thermal-to-Electric-Conversion (AMTEC) cells have been receiving increased attention and funding from the Department of Energy, NASA and the United States Air Force. Recently, sodium-BASE (Na-BASE) AMTEC cells were selected for the Advanced Radioisotope Power System (ARPS) program for the next generation of deep-space missions and spacecraft. Potassium-BASE (K-BASE) AMTEC cells have not received as much attention to date, even though the vapor pressure of potassium is higher than that of sodium at the same temperature. So that, K-BASE AMTEC cells with potentially higher open circuit voltage and higher power output than Na-BASE AMTEC cells are possible. Because the surface tension of potassium is about half of the surface tension of sodium at the same temperature, the artery and evaporator design in a potassium AMTEC cell has much more challenging pore size requirements than designs using sodium. This paper uses a flexible thermal/fluid/electrical model to predict the performance of a K-BASE AMTEC cell. Pore sizes in the artery of K-BASE AMTEC cells must be smaller by an order of magnitude than in Na-BASE AMTEC cells. The performance of a K-BASE AMTEC cell was higher than a Na-BASE AMTEC cell at low voltages/high currents. K-BASE AMTEC cells also have the potential of much better electrode performance, thereby creating another avenue for potentially better performance in K-BASE AMTEC cells

  20. Performance enhancement of PV cells through micro-channel cooling

    Directory of Open Access Journals (Sweden)

    Muzaffar Ali

    2015-11-01

    Full Text Available Efficiency of a PV cell is strongly dependent on its surface temperature. The current study is focused to achieve maximum efficiency of PV cells even in scorching temperatures in hot climates like Pakistan where the cell surface temperatures can even rise up to around 80 ℃. The study includes both the CFD and real time experimental investigations of a solar panel using micro channel cooling. Initially, CFD analysis is performed by developing a 3D model of a Mono-Crystalline cell with micro-channels to analyze cell surface temperature distribution at different irradiance and water flow rates. Afterwards, an experimental setup is developed for performance investigations under the real conditions of an open climate of a Pakistan's city, Taxila. Two 35W panels are manufactured for the experiments; one is based on the standard manufacturing procedure while other cell is developed with 4mm thick aluminum sheet having micro-channels of cross-section of 1mm by 1mm. The whole setup also includes different sensors for the measurement of solar irradiance, cell power, surface temperature and water flow rates. The experimental results show that PV cell surface temperature drop of around 15 ℃ is achieved with power increment of around 14% at maximum applied water flow rate of 3 LPM. Additionally, a good agreement is also found between CFD and experimental results. Therefore, that study clearly shows that a significant performance improvement of PV cells can be achieved through the proposed cell cooling technique.

  1. Emotional intelligence and its correlation to performance as a resident: a preliminary study.

    Science.gov (United States)

    Talarico, Joseph F; Metro, David G; Patel, Rita M; Carney, Patricia; Wetmore, Amy L

    2008-03-01

    To test the hypothesis that emotional intelligence, as measured by the Bar-On Emotional Quotient Inventory (EQ-I) 125 (Multi Health Systems, Toronto, Ontario, Canada) personal inventory, would correlate with resident performance. Prospective survey. University-affiliated, multiinstitutional anesthesiology residency program. Current clinical anesthesiology years one to three (PGY 2-4) anesthesiology residents enrolled in the University of Pittsburgh Anesthesiology Residency Program. Participants confidentially completed the Bar-On EQ-I 125 survey. Results of the individual EQ-I 125 and daily evaluations by the faculty of the residency program were compiled and analyzed. There was no positive correlation between any facet of emotional intelligence and resident performance. There was statistically significant negative correlation (-0.40; P Emotional intelligence, as measured by the Bar-On EQ-I personal inventory, does not strongly correlate to resident performance as defined at the University of Pittsburgh.

  2. Preliminary performance assessment strategy for single-shell tank waste disposal

    International Nuclear Information System (INIS)

    Sonnichsen, J.C. Jr.

    1991-10-01

    The disposal of the waste stored in single-shell tanks at the Hanford Site is recognized as a major environmental concern. A comprehensive program has been initiated to evaluate the various alternatives available for disposal of these wastes. Theses wastes will be disposed of in a manner consistent with applicable laws and regulations. Long-term waste isolation is one measure of performance that will be used for purposes of selection. The performance of each disposal alternative will be simulated using numerical models. Contained herein is a discussion of the strategy that has and continues to evolve to establish a general analytical framework to evaluate this performance. This general framework will be used to construct individual models of each waste disposal alternative selected for purposes of evaluation. 30 refs., 3 figs

  3. Improving International-Level Chess Players' Performance with an Acceptance-Based Protocol: Preliminary Findings

    Science.gov (United States)

    Ruiz, Francisco J.; Luciano, Carmen

    2012-01-01

    This study compared an individual, 4-hr intervention based on acceptance and commitment therapy (ACT) versus a no-contact control condition in improving the performance of international-level chess players. Five participants received the brief ACT protocol, with each matched to another chess player with similar characteristics in the control…

  4. A preliminary investigation on the effects of characteristics and contractual behaviour on civil engineering project performance

    Science.gov (United States)

    Ismail, W. N. W.; Adnan, H.; Yusuwan, N.; Maisham, M.; Hassan, A. A.

    2018-02-01

    The significant role of civil engineering project is not only to make the lives of people easier and secure but also to trigger the economic growth by providing infrastructure facilities as well as job opportunities. As it is dominantly initiated by government sectors, performance of the civil engineering projects is always observed. This study aims to investigate the characteristics of civil engineering project and the contractual behavior of the key participants and how do these two factors affect civil engineering projects performance. Literature reviews, content analysis and questionnaires survey were conducted to undertake the research. A total of 50 questionnaires were distributed and 10 questionnaires were returned, resulting in a 20% response rate. The research unveiled that performance of civil engineering projects are influenced greatly by the ability to handle the unpredictable character of the civil engineering projects and adequate behavioral management. Apart from that, balancing the factors with high quality of workmanship, avoidance or well managed conflicts and high satisfaction level will ensure performance in projects.

  5. Preliminary tests of a model of cooling-pond thermal performance

    International Nuclear Information System (INIS)

    Hicks, B.B.; Wesely, M.L.; Wilczek, J.

    1975-01-01

    Experiments performed during recent years at the cooling pond complex at the Dresden nuclear power station have been designed to improve our understanding of the fundamental properties of thermal exchange at a warm-water surface. To a considerable extent, the field studies have been successful in that they have shown that modern micrometeorological techniques can be successfully applied to the demanding circumstances of an industrial cooling lake at temperature of at least 40 0 C. The intent of these studies has been to create a set of parameterization schemes good enough to allow simulation of the performance of the Dresden cooling lake without adjustment of numerical constants. An obvious extension of these studies, and one of the goals of the cooling-pond research program as presently stated, is to obtain an accurate numerical simulation of thermal performance of ponds with use of the improved formulations that have resulted from the experimental work at the Dresden lake. The computer model is divided into two sections and can be used to test the sensitivity of predicted performance to variations in procedures for determining the thermal transfer from the surface

  6. Preliminary Assessment of Suomi-NPP VIIRS On-orbit Radiometric Performance

    Science.gov (United States)

    Oudrari, Hassan; DeLuccia, Frank; McIntire, Jeff; Moyer, David; Chiang, Vincent; Xiong, Xiao-xiong; Butler, James

    2012-01-01

    The Visible-Infrared Imaging Radiometer Suite (VIIRS) is a key instrument on-board the Suomi National Polar-orbiting Partnership (NPP) spacecraft that was launched on October 28th 2011. VIIRS was designed to provide moderate and imaging resolution of most of the globe twice daily. It is a wide-swath (3,040 km) cross-track scanning radiometer with spatial resolutions of 370.and 740 m at nadir for imaging and moderate bands, respectively. It has 22 spectral bands covering the spectrum between 0.412 11m and 12.01 11m, including 14 reflective solar bands (RSB), 7 thermal emissive bands (TEB), and 1 day-night band (ON B). VIIRS observations are used to generate 22 environmental data products (EORs). This paper will briefly describe NPP VIIRS calibration strategies performed by the independent government team, for the initial on-orbit Intensive Calibration and Validation (ICV) activities. In addition, this paper will provide an early assessment of the sensor on-orbit radiometric performance, such as the sensor signal to noise ratios (SNRs), dual gain transition verification, dynamic range and linearity, reflective bands calibration based on the solar diffuser (SO) and solar diffuser stability monitor (SOSM), and emissive bands calibration based on the on-board blackbody calibration (OBC). A comprehensive set of performance metrics generated during the pre-launch testing program will be compared to VIIRS on-orbit early performance, and a plan for future cal/val activities and performance enhancements will be presented.

  7. Gas-phase optical fiber photocatalytic reactors for indoor air application: a preliminary study on performance indicators

    Science.gov (United States)

    Palmiste, Ü.; Voll, H.

    2017-10-01

    The development of advanced air cleaning technologies aims to reduce building energy consumption by reduction of outdoor air flow rates while keeping the indoor air quality at an acceptable level by air cleaning. Photocatalytic oxidation is an emerging technology for gas-phase air cleaning that can be applied in a standalone unit or a subsystem of a building mechanical ventilation system. Quantitative information on photocatalytic reactor performance is required to evaluate the technical and economic viability of the advanced air cleaning by PCO technology as an energy conservation measure in a building air conditioning system. Photocatalytic reactors applying optical fibers as light guide or photocatalyst coating support have been reported as an approach to address the current light utilization problems and thus, improve the overall efficiency. The aim of the paper is to present a preliminary evaluation on continuous flow optical fiber photocatalytic reactors based on performance indicators commonly applied for air cleaners. Based on experimental data, monolith-type optical fiber reactor performance surpasses annular-type optical fiber reactors in single-pass removal efficiency, clean air delivery rate and operating cost efficiency.

  8. Serotonin transporter bi- and triallelic genotypes and their relationship with anxiety and academic performance: a preliminary study.

    Science.gov (United States)

    Calapoğlu, Mustafa; Sahin-Calapoğlu, Nilufer; Karaçöp, Ataman; Soyöz, Mustafa; Elyıldırım, Umit Y; Avşaroğlu, Selahattin

    2011-01-01

    Considerable evidence suggests that variation of the serotonin-transporter-linked promoter region (5- HTTLPR) is associated with anxiety-related traits. Academic outcomes are also more closely related to trait anxiety. This preliminary study aimed to explore the association between academic performance and levels of anxiety with respect to the bi- and triallelic classification of 5-HTTLPR polymorphism of the 5-HTT gene in teacher candidates. In our study, Spielberger's State-Trait Anxiety Inventory, the Selection Examination for Professional Posts in Public Organizations (KPSS) and 5-HTTLPR genotypes were used to investigate a group of 94 healthy teacher candidates. Higher anxiety scores were significantly associated with the S'S' genotype. There was no direct, statistically significant association between academic performance and genotypic groups regarding bi- and triallelic classification. However, the students who have L'L' or LL genotypes had the lowest levels of trait anxiety and the poorest academic performance. Additionally, there was a significant positive correlation between academic performance and anxiety levels. These findings support the idea that S and L(G) alleles are associated with anxiety-related traits, and that the S'S' genotype may be a good indicator for anxiety-related traits in a sample from the Turkish population. A specific degree of anxiety is considered to be a motivation for learning and high academic performance. However, 5-HTTLPR polymorphism of the 5-HTT gene may be one of the genetic factors affecting academic performance in connection with anxiety levels. Implications for incorporating anxiety management training in the educational process in terms of both environmental and individual factors will have a very important role in improving effective strategies for student personality services, as well as for development and planning. © 2010 S. Karger AG, Basel.

  9. Performance Characterization of Solid Oxide Cells Under High Pressure

    DEFF Research Database (Denmark)

    Sun, Xiufu; Bonaccorso, Alfredo Damiano; Graves, Christopher R.

    2015-01-01

    on partial pressures (oxygen, steam and hydrogen) were affected by increasing the pressure. In electrolysis mode at low current density, the performance improvement was counteracted by the increase in open circuit voltage, but it has to be borne in mind that the pressurized gas contains higher molar free......In this work, recent pressurized test results of a planar Ni- YSZ (YSZ: Yttria stabilized Zirconia) supported solid oxide cell are presented. Measurements were performed at 800 C in both fuel cell and electrolysis mode at different pressures. A comparison of the electrochemical performance...... of the cell at 1 and 3 bar shows a significant and equal performance gain at higher pressure in both fuel cell mode and electrolysis mode. Electrochemical impedance spectroscopy revealed that the serial resistance was not affected by the operation pressure; all the other processes that are dependent...

  10. STUDY OF PERFORMANCES OF ORGANIC SOLAR CELLS BY ...

    African Journals Online (AJOL)

    30 juin 2011 ... results of analysis of performances of organic solar cells by using what one call the datamining materials. ... Keywords: organic solar cells, gap energie, effiency, PCA. Author Correspondence .... oubli est malencontreux car le type de données disponibles influence toujours la direction de la recherche.

  11. Performance of an electrochemical solar cell with molybdenite anode

    International Nuclear Information System (INIS)

    Lima, G.F.; Chagas, J.W.R.; Cesar, H.L.; Juliao, J.F.

    1984-01-01

    The performance of photoeletrochemical cells for solar energy conversion, using photoanodes of molybdenite and platinum cathode is reported. Conversion efficiency between 0.1 and 1% were determined. The surface condition of the photoanode and the light absorption by the electrolite were some factors responsible for the low efficiency of those cells. (C.L.B.) [pt

  12. A hand-held imaging probe for radio-guided surgery: physical performance and preliminary clinical experience

    International Nuclear Information System (INIS)

    Pitre, S.; Menard, L.; Charon, Y.; Solal, M.; Garbay, J.R.

    2003-01-01

    Improvements in the specificity of radiopharmaceutical compounds have been paralleled by an upsurge of interest in developing small detectors to assist surgeons in localizing tumour tissue during surgery. This study reports the main technical features and physical characteristics of a new hand-held gamma camera dedicated to accurate and real-time intra-operative imaging. First clinical experience is also reported. The POCI (Per-operative Compact Imager) camera consists of a head module composed of a high-resolution interchangeable lead collimator and a CsI(Na) crystal plate optically coupled to an intensified position-sensitive diode. The current prototype has a 40-mm diameter field of view, an outer diameter of 9.5 cm, a length of 9 cm and a weight of 1.2 kg. Overall detector imaging characteristics were evaluated by technetium-99m phantom measurements. Three patients with breast cancer previously scheduled to undergo sentinel lymph node detection were selected for the preliminary clinical experience. Preoperative images of the lymphatic basin obtained using the POCI camera were compared with conventional transcutaneous explorations using a non-imaging gamma probe. The full-width at half-maximum (FWHM) spatial resolution was investigated in both air and scattering medium; when the phantom was placed in contact with the collimator, the POCI camera exhibited a 3.2 mm FWHM. The corresponding sensitivity was 290 cps/MBq. The preliminary clinical results showed that POCI was able to predict the number and location of all SLNs. In one case, two deep radioactive nodes missed by the gamma probe were detected on the intra-operative images. This very initial experience demonstrates that the physical performance of the POCI camera is adequate for radio-guided surgery. These results are sufficiently encouraging to prompt further evaluation studies designed to determine the specific and optimal clinical role of intra-operative imaging devices

  13. Preliminary study on functional performance of compound type multistage safety injection tank

    International Nuclear Information System (INIS)

    Bae, Youngmin; Kim, Young In; Kim, Keung Koo

    2015-01-01

    Highlights: • Functional performance of compound type multistage safety injection tanks is studied. • Effects of key design parameters are scrutinized. • Distinctive flow features in compound type safety injection tanks are explored. - Abstract: A parametric study is carried out to evaluate the functional performance of a compound type multistage safety injection tank that would be considered one of the components for the passive safety injection systems in nuclear power plants. The effects of key design parameters such as the initial volume fraction and charging pressure of gas, tank elevation, vertical location of a sparger, resistance coefficient, and operating condition on the injection flow rate are scrutinized along with a discussion of the relevant flow features. The obtained results indicate that the compound type multistage safety injection tank can effectively control the injection flow rate in a passive manner, by switching the driving force for the safety injection from gas pressure to gravity during the refill and reflood phases, respectively

  14. Preliminary evidence for performance enhancement following parietal lobe stimulation in Developmental Dyscalculia.

    Science.gov (United States)

    Iuculano, Teresa; Cohen Kadosh, Roi

    2014-01-01

    Nearly 7% of the population exhibit difficulties in dealing with numbers and performing arithmetic, a condition named Developmental Dyscalculia (DD), which significantly affects the educational and professional outcomes of these individuals, as it often persists into adulthood. Research has mainly focused on behavioral rehabilitation, while little is known about performance changes and neuroplasticity induced by the concurrent application of brain-behavioral approaches. It has been shown that numerical proficiency can be enhanced by applying a small-yet constant-current through the brain, a non-invasive technique named transcranial electrical stimulation (tES). Here we combined a numerical learning paradigm with transcranial direct current stimulation (tDCS) in two adults with DD to assess the potential benefits of this methodology to remediate their numerical difficulties. Subjects learned to associate artificial symbols to numerical quantities within the context of a trial and error paradigm, while tDCS was applied to the posterior parietal cortex (PPC). The first subject (DD1) received anodal stimulation to the right PPC and cathodal stimulation to the left PPC, which has been associated with numerical performance's improvements in healthy subjects. The second subject (DD2) received anodal stimulation to the left PPC and cathodal stimulation to the right PPC, which has been shown to impair numerical performance in healthy subjects. We examined two indices of numerical proficiency: (i) automaticity of number processing; and (ii) mapping of numbers onto space. Our results are opposite to previous findings with non-dyscalculic subjects. Only anodal stimulation to the left PPC improved both indices of numerical proficiency. These initial results represent an important step to inform the rehabilitation of developmental learning disabilities, and have relevant applications for basic and applied research in cognitive neuroscience, rehabilitation, and education.

  15. A Preliminary Investigation into Cognitive Aptitudes Predictive of Overall MQ-1 Predator Pilot Qualification Training Performance

    Science.gov (United States)

    2015-11-06

    of the Wechsler Adult Intelligence Scale and Wechsler’s theory of intelligence [12]. The MAB-II manual has well-documented internal consistency... Wechsler Adult Intelligence Scale -3rd Edition (WAIS-3®). San Antonio (TX): Harcourt Assessment; 1997. 13. Powell DH, Kaplan EF, Whitla D, Weintraub S...n = 46) Adequate Performers M (SD) (n = 43) r rc Intelligence Quotients Full Scale 120.26 (16.83) 118.30 (6.60) .08

  16. Preliminary Study on Evaluation of Impact Resistance Performance of Fiber Reinforced Concrete Walls

    International Nuclear Information System (INIS)

    Jin, Byeong Moo; Lee, Yun Seok; Kim, Young Jin; Jeon, Se Jin

    2012-01-01

    As the safety assessments of nuclear power plants for the hypothetical large civil aircraft crash should be made mandatory, studies on large aircraft-nuclear power plant impact analyses and assessments studies are actively in progress. For the safety assessment of nuclear power plants against large civil aircraft crash, it is practically impossible to conduct full-scale experiments. Therefore, analysis using general purpose numerical analysis program accompanied by scale model experiments and element experiments has been adopted for the safety assessment. The safety of nuclear power plants against large civil aircraft crash is able to be accomplished by enhancement of the impact resistance performance, such as increasing the wall thickness, increasing the strength of concrete and using the fiber reinforced concrete which is able to be acquired by relatively simple process of adding fibers to a concrete mix without significant change of design and construction. A research for the enhancement of impact resistance performance depending upon design parameters for fiber reinforced concrete, such as type of fibers and application rate, is in progress. In this study, before the safety assessment of nuclear power plants against large civil aircraft crash, we assess the impact resistance performance of concrete wall depending upon type of fibers and impact velocity of objects

  17. Evaluation of Muscle Performance in Patients with Vitamin D De ciency: Preliminary Study

    Directory of Open Access Journals (Sweden)

    Gökhan Tuna Öztürk

    2013-04-01

    Full Text Available Aim: Vitamin D de ciency is very common in general population and has potentially harmful effect on musculoskeletal system. We aimed to show the effect of vitamin D de ciency on the muscle performance by using isokinetic test. Meterial and Methods: This study includes 12 women with vitamin D de ciency for patient group and 12 healthy women for control group. We compared knee muscles performance of these two groups by using isokinetic test. Results: The mean age was 40.71 (26-57 years in patients and 41.43 (28-58 years in healthy group. There was no statistical difference between two groups at knee  exion and extension pick-torque values in 60°/s velocity and fatigue index in 180°/s velocity (respectively, p1=0.86, p2=0.12, p3=0.42. Conclusion: Vitamin D de ciency has no effect on muscle performance. Further invastigations that evaluating larger populations are needed. (Turkish Journal of Osteoporosis 2013;19: 17-9

  18. Performance environment and nested task constraints influence long jump approach run: a preliminary study.

    Science.gov (United States)

    Panteli, Flora; Smirniotou, Athanasia; Theodorou, Apostolos

    2016-01-01

    The purpose of the study was to investigate possible changes at step pattern and technical performance of the long jump approach run in seven young long jumpers by modifying the performance environment (long jump runway versus track lane) and the nested actions (run-through with take-off versus complete long jump). Our findings suggest that the step pattern and technical aspects of the approach run are affected by environmental context and nested task constraints. In terms of environmental context, it appears that practising the training routine of run-through followed by take-off on the long jump runway allows athletes to simulate competition conditions in terms of step regulation and technical efficacy. The task of run-through followed by take-off on the track lane failed to initiate visual perception, step regulation and technical efficiency at the steps preceding the instant of take-off. In terms of nested task constraints, when run-ups were followed by jump for distance instead of only a take-off, a higher level of consistency was achieved and step regulation was based on perception-action coupling. Practising long jump run-up accuracy at a setting not containing the informational elements of the performance environment fails to develop the key elements of the skill.

  19. Preliminary Study on Evaluation of Impact Resistance Performance of Fiber Reinforced Concrete Walls

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Byeong Moo; Lee, Yun Seok; Kim, Young Jin [Daewoo E and C Co. Ltd., Suwon (Korea, Republic of); Jeon, Se Jin [Ajou University, Suwon (Korea, Republic of)

    2012-05-15

    As the safety assessments of nuclear power plants for the hypothetical large civil aircraft crash should be made mandatory, studies on large aircraft-nuclear power plant impact analyses and assessments studies are actively in progress. For the safety assessment of nuclear power plants against large civil aircraft crash, it is practically impossible to conduct full-scale experiments. Therefore, analysis using general purpose numerical analysis program accompanied by scale model experiments and element experiments has been adopted for the safety assessment. The safety of nuclear power plants against large civil aircraft crash is able to be accomplished by enhancement of the impact resistance performance, such as increasing the wall thickness, increasing the strength of concrete and using the fiber reinforced concrete which is able to be acquired by relatively simple process of adding fibers to a concrete mix without significant change of design and construction. A research for the enhancement of impact resistance performance depending upon design parameters for fiber reinforced concrete, such as type of fibers and application rate, is in progress. In this study, before the safety assessment of nuclear power plants against large civil aircraft crash, we assess the impact resistance performance of concrete wall depending upon type of fibers and impact velocity of objects

  20. Preliminary evidence for performance enhancement following parietal lobe stimulation in Developmental Dyscalculia

    Directory of Open Access Journals (Sweden)

    Teresa eIuculano

    2014-02-01

    Full Text Available Nearly 7% of the population exhibit difficulties in dealing with numbers and performing arithmetic, a condition named Developmental Dyscalculia (DD, which significantly affects the educational and professional outcomes of these individuals, as it often persists into adulthood. Research has mainly focused on behavioral rehabilitation, while little is known about performance changes and neuroplasticity induced by the concurrent application of brain-behavioral approaches. It has been shown that numerical proficiency can be enhanced by applying a small – yet constant – current through the brain, a non-invasive technique named transcranial electrical stimulation (tES. Here we combined a numerical learning paradigm with transcranial direct current stimulation (tDCS in two adults with DD to assess the potential benefits of this methodology to remediate their numerical difficulties. Subjects learned to associate artificial symbols to numerical quantities within the context of a trial and error paradigm, while tDCS was applied to the posterior parietal cortex (PPC. The first subject (DD1 received anodal stimulation to the right PPC and cathodal stimulation to the left PPC, which has been associated with numerical performance’s improvements in healthy subjects. The second subject (DD2 received anodal stimulation to the left PPC and cathodal stimulation to the right PPC, which has been shown to impair numerical performance in healthy subjects. We examined two indices of numerical proficiency: (i automaticity of number processing; and (ii mapping of numbers onto space. Our results are opposite to previous findings with non-dyscalculic subjects. Only anodal stimulation to the left PPC improved both indices of numerical proficiency. These initial results represent an important step to inform the rehabilitation of developmental learning disabilities, and have relevant applications for basic and applied research in cognitive neuroscience, rehabilitation

  1. Evaluating Method Engineer Performance: an error classification and preliminary empirical study

    Directory of Open Access Journals (Sweden)

    Steven Kelly

    1998-11-01

    Full Text Available We describe an approach to empirically test the use of metaCASE environments to model methods. Both diagrams and matrices have been proposed as a means for presenting the methods. These different paradigms may have their own effects on how easily and well users can model methods. We extend Batra's classification of errors in data modelling to cover metamodelling, and use it to measure the performance of a group of metamodellers using either diagrams or matrices. The tentative results from this pilot study confirm the usefulness of the classification, and show some interesting differences between the paradigms.

  2. Cooling via one hand improves physical performance in heat-sensitive individuals with Multiple Sclerosis: A preliminary study

    Directory of Open Access Journals (Sweden)

    Murray Julie

    2008-05-01

    Full Text Available Abstract Background Many individuals afflicted with multiple sclerosis (MS experience a transient worsening of symptoms when body temperature increases due to ambient conditions or physical activity. Resulting symptom exacerbations can limit performance. We hypothesized that extraction of heat from the body through the subcutaneous retia venosa that underlie the palmar surfaces of the hands would reduce exercise-related heat stress and thereby increase the physical performance capacity of heat-sensitive individuals with MS. Methods Ten ambulatory MS patients completed one or more randomized paired trials of walking on a treadmill in a temperate environment with and without cooling. Stop criteria were symptom exacerbation and subjective fatigue. The cooling treatment entailed inserting one hand into a rigid chamber through an elastic sleeve that formed an airtight seal around the wrist. A small vacuum pump created a -40 mm Hg subatmospheric pressure enviinside the chamber where the palmar surface of the hand rested on a metal surface maintained at 18–22°C. During the treatment trials, the device was suspended from above the treadmill on a bungee cord so the subjects could comfortably keep a hand in the device without having to bear its weight while walking on the treadmill. Results When the trials were grouped by treatment only, cooling treatment increased exercise durations by 33% (43.6 ± 17.1 min with treatment vs. 32.8 ± 10.9 min. without treatment, mean ± SD, p -6, paired t-test, n = 26. When the average values were calculated for the subjects who performed multiple trials before the treatment group results were compared, cooling treatment increased exercise duration by 35% (42.8 ± 16.4 min with treatment vs. 31.7 ± 9.8 min. without treatment, mean ± SD, p Conclusion These preliminary results suggest that utilization of the heat transfer capacity of the non-hairy skin surfaces can enable temperature-sensitive individuals with MS to

  3. Evaluation of Exercise Tolerance in Dialysis Patients Performing Tai Chi Training: Preliminary Study

    Directory of Open Access Journals (Sweden)

    Wioletta Dziubek

    2016-01-01

    Full Text Available Introduction. Patients with end-stage renal disease (ESRD have poor physical performance and exercise capacity due to frequent dialysis treatments. Tai Chi exercises can be very useful in the area of rehabilitation of people with ESRD. Objectives. The aim of the study was to assess exercise capacity in ESRD patients participating in 6-month Tai Chi training. Patients and Methods. Twenty dialysis patients from Wroclaw took part in the training; at the end of the project, 14 patients remained (age 69.2±8.6 years. A 6-minute walk test (6MWT and spiroergometry were performed at the beginning and after 6 months of training. Results. After 6 months of Tai Chi, significant improvements were recorded in mean distance in the 6MWT (387.89 versus 436.36 m, rate of perceived exertion (7.4 versus 4.7, and spiroergometry (8.71 versus 10.08 min. Conclusions. In the ESRD patients taking part in Tai Chi training, a definite improvement in exercise tolerance was recorded after the 6-month training. Tai Chi exercises conducted on days without dialysis can be an effective and interesting form of rehabilitation for patients, offering them a chance for a better quality of life and fewer falls and hospitalisations that are the result of it.

  4. Preliminary performance assessment for the Waste Isolation Pilot Plant, December 1992

    International Nuclear Information System (INIS)

    1993-08-01

    Before disposing of transuranic radioactive waste in the Waste Isolation Pilot Plant (WIPP), the United States Department of Energy (DOE) must evaluate compliance with applicable long-term regulations of the United States Environmental Protection Agency (EPA). Sandia National Laboratories is conducting iterative performance assessments (PAs) of the WIPP for the DOE to provide interim guidance while preparing for a final compliance evaluation. This volume of the 1992 PA contains results of uncertainty and sensitivity analyses with respect to the EPA's Environmental Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes (40 CFR 191, Subpart B). Additional information about the 1992 PA is provided in other volumes. Results of the 1992 uncertainty and sensitivity analyses indicate that, conditional on the modeling assumptions, the choice of parameters selected for sampling, and the assigned parameter-value distributions, the most important parameters for which uncertainty has the potential to affect compliance with 40 CFR 191B are: drilling intensity, intrusion borehole permeability, halite and anhydrite permeabilities, radionuclide solubilities and distribution coefficients, fracture spacing in the Culebra Dolomite Member of the Rustler Formation, porosity of the Culebra, and spatial variability of Culebra transmissivity. Performance with respect to 40 CFR 191B is insensitive to uncertainty in other parameters; however, additional data are needed to confirm that reality lies within the assigned distributions

  5. Enhanced photovoltaic performance of an inclined nanowire array solar cell.

    Science.gov (United States)

    Wu, Yao; Yan, Xin; Zhang, Xia; Ren, Xiaomin

    2015-11-30

    An innovative solar cell based on inclined p-i-n nanowire array is designed and analyzed. The results show that the inclined geometry can sufficiently increase the conversion efficiency of solar cells by enhancing the absorption of light in the active region. By tuning the nanowire array density, nanowire diameter, nanowire length, as well as the proportion of intrinsic region of the inclined nanowire solar cell, a remarkable efficiency in excess of 16% can be obtained in GaAs. Similar results have been obtained in InP and Si nanowire solar cells, demonstrating the universality of the performance enhancement of inclined nanowire arrays.

  6. Solid Polymer Fuel Cells. Electrode and membrane performance studies

    Energy Technology Data Exchange (ETDEWEB)

    Moeller-Holst, S.

    1996-12-31

    This doctoral thesis studies aspects of fuel cell preparation and performance. The emphasis is placed on preparation and analysis of low platinum-loading solid polymer fuel cell (SPEC) electrodes. A test station was built and used to test cells within a wide range of real operating conditions, 40-150{sup o}C and 1-10 bar. Preparation and assembling equipment for single SPFCs was designed and built, and a new technique of spraying the catalyst layer directly onto the membrane was successfully demonstrated. Low Pt-loading electrodes (0.1 mg Pt/cm{sup 2}) prepared by the new technique exhibited high degree of catalyst utilization. The performance of single cells holding these electrodes is comparable to state-of-the-art SPFCs. Potential losses in single cell performance are ascribed to irreversibilities by analysing the efficiency of the Solid Oxide Fuel Cell by means of the second law of thermodynamics. The water management in membranes is discussed for a model system and the results are relevant to fuel cell preparation and performance. The new spray deposition technique should be commercially interesting as it involves few steps as well as techniques that are adequate for larger scale production. 115 refs., 43 figs., 18 tabs.

  7. Solid Polymer Fuel Cells. Electrode and membrane performance studies

    Energy Technology Data Exchange (ETDEWEB)

    Moeller-Holst, S

    1997-12-31

    This doctoral thesis studies aspects of fuel cell preparation and performance. The emphasis is placed on preparation and analysis of low platinum-loading solid polymer fuel cell (SPEC) electrodes. A test station was built and used to test cells within a wide range of real operating conditions, 40-150{sup o}C and 1-10 bar. Preparation and assembling equipment for single SPFCs was designed and built, and a new technique of spraying the catalyst layer directly onto the membrane was successfully demonstrated. Low Pt-loading electrodes (0.1 mg Pt/cm{sup 2}) prepared by the new technique exhibited high degree of catalyst utilization. The performance of single cells holding these electrodes is comparable to state-of-the-art SPFCs. Potential losses in single cell performance are ascribed to irreversibilities by analysing the efficiency of the Solid Oxide Fuel Cell by means of the second law of thermodynamics. The water management in membranes is discussed for a model system and the results are relevant to fuel cell preparation and performance. The new spray deposition technique should be commercially interesting as it involves few steps as well as techniques that are adequate for larger scale production. 115 refs., 43 figs., 18 tabs.

  8. A Preliminary Model for Spacecraft Propulsion Performance Analysis Based on Nuclear Gain and Subsystem Mass-Power Balances

    Science.gov (United States)

    Chakrabarti, Suman; Schmidt, George R.; Thio, Y. C.; Hurst, Chantelle M.

    1999-01-01

    A preliminary model for spacecraft propulsion performance analysis based on nuclear gain and subsystem mass-power balances are presented in viewgraph form. For very fast missions with straight-line trajectories, it has been shown that mission trip time is proportional to the cube root of alpha. Analysis of spacecraft power systems via a power balance and examination of gain vs. mass-power ratio has shown: 1) A minimum gain is needed to have enough power for thruster and driver operation; and 2) Increases in gain result in decreases in overall mass-power ratio, which in turn leads to greater achievable accelerations. However, subsystem mass-power ratios and efficiencies are crucial: less efficient values for these can partially offset the effect of nuclear gain. Therefore, it is of interest to monitor the progress of gain-limited subsystem technologies and it is also possible that power-limited systems with sufficiently low alpha may be competitive for such ambitious missions. Topics include Space flight requirements; Spacecraft energy gain; Control theory for performance; Mission assumptions; Round trips: Time and distance; Trip times; Vehicle acceleration; and Minimizing trip times.

  9. A preliminary assessment of financial stability, efficiency, health systems and health outcomes using performance-based contracts in Belize.

    Science.gov (United States)

    Bowser, Diana M; Figueroa, Ramon; Natiq, Laila; Okunogbe, Adeyemi

    2013-01-01

    Over the last 10 years, Belize has implemented a National Health Insurance (NHI) program that uses performance-based contracts with both public and private facilities to improve financial sustainability, efficiency and service provision. Data were collected at the facility, district and national levels in order to assess trends in financial sustainability, efficiency payments, year-end bonuses and health system and health outcomes. A difference-in-difference approach was used to assess the difference in technical efficiency between private and public facilities. The results show that per capita spending on services provided by the NHI program has decreased over the period 2006-2009 from BZ$177 to BZ$136. The private sector has achieved higher levels of technical efficiency, but lower percentages of efficiency and year-end bonus payments. Districts with contracts through the NHI program showed greater improvements in facility births, nurse density, reducing maternal mortality, diabetes deaths and morbidity from bronchitis, emphysema and asthma than districts without contracts over the period 2006-2010. This preliminary assessment of Belize's pay-for-performance system provides some positive results, however further research is needed to use the lessons learned from Belize to implement similar reforms in other systems.

  10. Preliminary measurement performance evaluation of a new white light interferometer for cylindrical surfaces

    International Nuclear Information System (INIS)

    Albertazzi, Armando Jr; Pont, Alex Dal

    2005-01-01

    This paper introduces a new design of a white light interferometer, suitable for measurement of cylindrical or quasi-cylindrical parts. A high precision 45 deg. conical mirror is used to direct collimated light radially, making it possible to measure in true cylindrical coordinates. The image of the measurand, distorted by the conical mirror, is projected in a high resolution digital camera. A mapping algorithm is used to reconstruct the cylindrical geometry from the distorted image. The rest of the interferometer is quite similar to a conventional white light interferometer: A flat reference mirror is scanned through the measurement range while an algorithm is searching for the maximum contrast position of the interference pattern. The performance evaluation of a configuration suitable for measurement of external cylindrical surfaces is also presented in this paper. A master cylinder was used as reference. Uncertainties of about 1.0 μm were found at the present stage of development

  11. Preliminary results on performance testing of a turbocharged rotary combustion engine

    Science.gov (United States)

    Meng, P. R.; Rice, W. J.; Schock, H. J.; Pringle, D. P.

    1982-01-01

    The performance of a turbocharged rotary engine at power levels above 75 kW (100 hp) was studied. A twin rotor turbocharged Mazda engine was tested at speeds of 3000 to 6000 rpm and boost pressures to 7 psi. The NASA developed combustion diagnostic instrumentation was used to quantify indicated and pumping mean effect pressures, peak pressure, and face to face variability on a cycle by cycle basis. Results of this testing showed that a 5900 rpm a 36 percent increase in power was obtained by operating the engine in the turbocharged configuration. When operating with lean carburetor jets at 105 hp (78.3 kW) and 4000 rpm, a brake specific fuel consumption of 0.45 lbm/lb-hr was measured.

  12. Preliminary study on performance of a coupled hydrodynamic and sediment transport model on small domain

    Science.gov (United States)

    Rasyif, Teuku M.; Kato, Shigeru; Syamsidik, Okabe, Takumi

    2017-10-01

    Numerical simulation is one of the useful tools to analyze natural phenomena in the earth such as the tsunami disaster. Several numerical models can simulate the tsunami wave from its generation, propagation, and inundation. However, most tsunami models do not include the sediment transport module. The tsunami wave actually induces a lot of sediment during the propagation in the coastal area. In the case of Indian Ocean Tsunami in 2004, massive morphological changes were caused by the tsunami waves around Sumatra coast. In Aceh, some areas eroded by the tsunami wave were living place for a local community. It is indispensable for the resident in the coastal area to estimate the risk of morphological changes due to a tsunami wave. Therefore, a model that can investigate the morphological changes due tsunami wave is necessary. The result of this model can be used to consider a countermeasure for tsunami wave impact in the coastal area, such as land-use management and planning. The COMCOT-SED model had been developed by several researchers. This model combines the hydrodynamic module and the sediment module. The aim of this study is to get general information about performance of the COMCOT-SED model and to modify the model for more accurate results. Firstly, the model was demonstrated in the ideal condition to confirm the model validity. Then, we evaluated the model performance comparing the model results and the laboratory experiment data which was conducted by other researcher. The authors found that the results of water level and bottom profile by the original model in the ideal condition are not suitable. The model modification will give us more suitable results. The modified model will be applied to simulate the tsunami wave and sediment transport in the small area.

  13. Correlation between impurities, defects and cell performance in semicrystalline silicon

    International Nuclear Information System (INIS)

    Doolittle, W.A.; Rohatgi, A.

    1990-01-01

    This paper reports that an in-depth analysis of Solarex CDS semicrystalline silicon has been performed and correlations between the efficiency and impurities, and defects present in the material have been made. Comparisons were made between cell performance and variations in interstitial oxygen, substitutional carbon, grain size, etch pit density, and trap location as a function of position in the ingot. The oxygen concentration was found to decrease with increasing distance from the bottom of the ingot while the carbon concentration as well as average grain size was found to increase. The best cell performance was obtained on wafers with minimum oxygen and maximum carbon (top). No correlation was found between etch pit density and cell performance. DLTS and JVT measurements revealed that samples with higher oxygen content (bottom) gave lower cell performance due to a large number of distributed states, possibly due to extended defects like oxygen precipitates. Low oxygen samples (top) showed predominately discrete states, improved cell performance and a doping dependent average trap density

  14. Preliminary study on gas separation performance of flat sheet mixed matrix (PVDF/Zeolite)

    Science.gov (United States)

    Rahman, Sunarti Abd; Abdalla Suliman Haron, Gamal; Krishna Roshan Kanasan, Raj; Hasbullah, Hasrinah

    2018-04-01

    Membrane separation has attracted a lot of attention over the last years mainly due to its separation ability, operational capability and economical viability. Mixed matrix membrane (MMM) combines the superior transport and selectivity properties of inorganic membrane materials and the excellent fabrication properties of organic polymers. This emerging technology can be utilized to purify biogas which can be used in a variety of applications. In this study, flat sheet mixed matrix membranes were synthesized with different percentages of N-Mehtyl-2-pyrrolidone (NMP) as solvent, Polyvinylidene Fluoride (PVDF) as the polymer matrix and zeolite 4A as the dispersed fine particles, membrane A (80: 20: 0), membrane B (80: 18: 2), membrane C (80: 15: 5), and membrane D (75: 15: 10) respectively. The membranes were fabricated using dry/wet phase inversion method. The membrane’s performance in terms of permeability and selectivity was examined using the single gas permeation device. The general trend was that, the permeability of the two gases (CO2/CH4) decreased with the increase of the pressure (0.5, 1, 1.5) bar. Membrane D was found to be suitable to separate the pair gas (CO2/CH4) as the permeability was 65623.412, Barrer and 15587.508, Barrer respectively, and its selectivity for was 4.21 at 0.5 bar.

  15. Multivariate regression applied to the performance optimization of a countercurrent ultracentrifuge - a preliminary study

    International Nuclear Information System (INIS)

    Migliavacca, Elder; Andrade, Delvonei Alves de

    2004-01-01

    In this work, the least-squares methodology with covariance matrix is applied to determine a data curve fitting in order to obtain a performance function for the separative power δU of a ultracentrifuge as a function of variables that are experimentally controlled. The experimental data refer to 173 experiments on the ultracentrifugation process for uranium isotope separation. The experimental uncertainties related with these independent variables are considered in the calculation of the experimental separative power values, determining an experimental data input covariance matrix. The process control variables, which significantly influence the δU values, are chosen in order to give information on the ultracentrifuge behaviour when submitted to several levels of feed flow F and cut θ . After the model goodness-of-fit validation, a residual analysis is carried out to verify the assumed basis concerning its randomness and independence and mainly the existence of residual heterocedasticity with any regression model variable. The response curves are made relating the separative power with the control variables F and θ, to compare the fitted model with the experimental data and finally to calculate their optimized values. (author)

  16. Executive functioning performance predicts subjective and physiological acute stress reactivity: preliminary results.

    Science.gov (United States)

    Hendrawan, Donny; Yamakawa, Kaori; Kimura, Motohiro; Murakami, Hiroki; Ohira, Hideki

    2012-06-01

    Individual differences in baseline executive functioning (EF) capacities have been shown to predict state anxiety during acute stressor exposure. However, no previous studies have clearly demonstrated the relationship between EF and physiological measures of stress. The present study investigated the efficacy of several well-known EF tests (letter fluency, Stroop test, and Wisconsin Card Sorting Test) in predicting both subjective and physiological stress reactivity during acute psychosocial stress exposure. Our results show that letter fluency served as the best predictor for both types of reactivity. Specifically, the higher the letter fluency score, the lower the acute stress reactivity after controlling for the baseline stress response, as indicated by lower levels of state anxiety, negative mood, salivary cortisol, and skin conductance. Moreover, the predictive power of the letter fluency test remained significant for state anxiety and cortisol indices even after further adjustments for covariates by adding the body mass index (BMI) as a covariate. Thus, good EF performance, as reflected by high letter fluency scores, may dampen acute stress responses, which suggests that EF processes are directly associated with aspects of stress regulation. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Preliminary Performance Assessment for the Waste Management Area C at the Hanford Site in Southeast Washington

    International Nuclear Information System (INIS)

    Bergeron, Marcel P.; Singleton, Kristin M.; Eberlein, Susan J.

    2015-01-01

    A performance assessment (PA) of Single-Shell Tank (SST) Waste Management Area C (WMA C) located at the U.S. Department of Energy's (DOE) Hanford Site in southeastern Washington is being conducted to satisfy the requirements of the Hanford Federal Facility Agreement and Consent Order (HFFACO), as well as other Federal requirements and State-approved closure plans and permits. The WMP C PA assesses the fate, transport, and impacts of radionuclides and hazardous chemicals within residual wastes left in tanks and ancillary equipment and facilities in their assumed closed configuration and the subsequent risks to humans into the far future. The part of the PA focused on radiological impacts is being developed to meet the requirements for a closure authorization under DOE Order 435.1 that includes a waste incidental to reprocessing determination for residual wastes remaining in tanks, ancillary equipment, and facilities. An additional part of the PA will evaluate human health and environmental impacts from hazardous chemical inventories in residual wastes remaining in WMA C tanks, ancillary equipment, and facilities needed to meet the requirements for permitted closure under RCRA.

  18. Preliminary evaluation of SensHand V1 in assessing motor skills performance in Parkinson disease.

    Science.gov (United States)

    Cavallo, Filippo; Esposito, Dario; Rovini, Erika; Aquilano, Michela; Carrozza, Maria Chiara; Dario, Paolo; Maremmani, Carlo; Bongioanni, Paolo

    2013-06-01

    Nowadays, the increasing old population 65+ as well as the pace imposed by work activities lead to a high number of people that have particular injuries for limbs. In addition to persistent or temporary disabilities related to accidental injuries we must take into account that part of the population suffers from motor deficits of the hands due to stroke or diseases of various clinical nature. The most recurrent technological solutions to measure the rehabilitation or skill motor performance of the hand are glove-based devices, able to faithfully capture the movements of the hand and fingers. This paper presents a system for hand motion analysis based on 9-axis complete inertial modules and dedicated microcontroller which are fixed on fingers and forearm. The technological solution presented is able to track the patients' hand motions in real-time and then to send data through wireless communication reducing the clutter and the disadvantages of a glove equipped with sensors through a different technological structure. The device proposed has been tested in the study of Parkinson's disease.

  19. Preparation and Preliminary Dialysis Performance Research of Polyvinylidene Fluoride Hollow Fiber Membranes

    Science.gov (United States)

    Zhang, Qinglei; Lu, Xiaolong; Liu, Juanjuan; Zhao, Lihua

    2015-01-01

    In this study, the separation properties of Polyvinylidene fluoride (PVDF) hollow fiber hemodialysis membranes were improved by optimizing membrane morphology and structure. The results showed that the PVDF membrane had better mechanical and separation properties than Fresenius Polysulfone High-Flux (F60S) membrane. The PVDF membrane tensile stress at break, tensile elongation and bursting pressure were 11.3 MPa, 395% and 0.625 MPa, respectively. Ultrafiltration (UF) flux of pure water reached 108.2 L∙h−1∙m−2 and rejection of Albumin from bovine serum was 82.3%. The PVDF dialyzers were prepared by centrifugal casting. The influences of membrane area and simulate fluid flow rate on dialysis performance were investigated. The results showed that the clearance rate of urea and Lysozyme (LZM) were improved with increasing membrane area and fluid flow rate while the rejection of albumin from bovine serum (BSA) had little influence. The high-flux PVDF dialyzer UF coefficient reached 62.6 mL/h/mmHg. The PVDF dialyzer with membrane area 0.69 m2 has the highest clearance rate to LZM and urea. The clearance rate of LZM was 66.8% and urea was 87.7%. PMID:25807890

  20. Preliminary Performance Assessment for the Waste Management Area C at the Hanford Site in Southeast Washington

    Energy Technology Data Exchange (ETDEWEB)

    Bergeron, Marcel P. [Washington River Protection Solutions LLC, Richland, WA (United States); Singleton, Kristin M. [Washington River Protection Solutions LLC, Richland, WA (United States); Eberlein, Susan J. [Washington River Protection Solutions LLC, Richland, WA (United States)

    2015-01-07

    A performance assessment (PA) of Single-Shell Tank (SST) Waste Management Area C (WMA C) located at the U.S. Department of Energy's (DOE) Hanford Site in southeastern Washington is being conducted to satisfy the requirements of the Hanford Federal Facility Agreement and Consent Order (HFFACO), as well as other Federal requirements and State-approved closure plans and permits. The WMP C PA assesses the fate, transport, and impacts of radionuclides and hazardous chemicals within residual wastes left in tanks and ancillary equipment and facilities in their assumed closed configuration and the subsequent risks to humans into the far future. The part of the PA focused on radiological impacts is being developed to meet the requirements for a closure authorization under DOE Order 435.1 that includes a waste incidental to reprocessing determination for residual wastes remaining in tanks, ancillary equipment, and facilities. An additional part of the PA will evaluate human health and environmental impacts from hazardous chemical inventories in residual wastes remaining in WMA C tanks, ancillary equipment, and facilities needed to meet the requirements for permitted closure under RCRA.

  1. Effects of impurities on silicon solar-cell performance

    Science.gov (United States)

    Hopkins, R. H.

    1986-01-01

    Model analyses indicate that sophisticated solar cell designs (back surface fields, optical reflectors, surface passivation, and double layer antireflective coatings) can produce devices with conversion efficiencies above 20%. To realize this potential, the quality of the silicon from which the cells are made must be improved; and these excellent electrical properties must be maintained during device processing. As the cell efficiency rises, the sensitivity to trace contaminants also increases. For example, the threshold Ti impurity concentraion at which cell performance degrades is more than an order of magnitude lower for an 18% cell than for a 16% cell. Similar behavior occurs for numerous other metal species which introduce deep level traps that stimulate the recombination of photogenerated carriers in silicon. Purification via crystal growth in conjunction with gettering steps to preserve the large diffusion length of the as grown material can lead to the production of devices with efficiencies above 18%, as verified experimentally.

  2. High performance direct methanol fuel cell with thin electrolyte membrane

    Science.gov (United States)

    Wan, Nianfang

    2017-06-01

    A high performance direct methanol fuel cell is achieved with thin electrolyte membrane. 320 mW cm-2 of peak power density and over 260 mW cm-2 at 0.4 V are obtained when working at 90 °C with normal pressure air supply. It is revealed that the increased anode half-cell performance with temperature contributes primarily to the enhanced performance at elevated temperature. From the comparison of iR-compensated cathode potential of methanol/air with that of H2/air fuel cell, the impact of methanol crossover on cathode performance decreases with current density and becomes negligible at high current density. Current density is found to influence fuel efficiency and methanol crossover significantly from the measurement of fuel efficiency at different current density. At high current density, high fuel efficiency can be achieved even at high temperature, indicating decreased methanol crossover.

  3. The performance of silicon solar cells operated in liquids

    International Nuclear Information System (INIS)

    Wang Yiping; Fang Zhenlei; Zhu Li; Huang Qunwu; Zhang Yan; Zhang Zhiying

    2009-01-01

    Better performance can be achieved when the bare silicon solar cells are immersed into liquids for the enhanced heat removing. In this study, the performance of solar cells immersed in liquids was examined under simulated sunlight. To distinguish the effects of the liquid optic and electric properties on the solar cells, a comparison between immersion of the solar module and the bare solar cells was carried out. It was found that the optic properties of the liquids can cause minor efficiency changes on the solar cells, while the electric properties of the liquids, the molecular polarizable and ions, are responsible for the most of the changes. The bare solar cells immersed in the non-polar silicon oil have the best performance. The accelerated life tests were carried out at 150 deg. C high temperature and under 200 W/m 2 ultraviolet light irradiation, respectively. It was found that the silicon oil has good stability. This study can give support on the cooling of the concentrated photovoltaic systems by immersing the solar cells in the liquids directly

  4. Provesicular granisetron hydrochloride buccal formulations: in vitro evaluation and preliminary investigation of in vivo performance.

    Science.gov (United States)

    Ahmed, Sami; El-Setouhy, Doaa Ahmed; El-Latif Badawi, Alia Abd; El-Nabarawi, Mohamed Ahmed

    2014-08-18

    Granisetron hydrochloride (granisetron) is a potent antiemetic that has been proven to be effective in acute and delayed emesis in cancer chemotherapy. Granisetron suffers from reduced oral bioavailability (≈60%) due to hepatic metabolism. In this study the combined advantage of provesicular carriers and buccal drug delivery has been explored aiming to sustain effect and improve bioavailability of granisetron via development of granisetron provesicular buccoadhesive tablets with suitable quality characteristics (hardness, drug content, in vitro release pattern, exvivo bioadhesion and in vivo bioadhesion behavior). Composition of the reconstituted niosomes from different prepared provesicular carriers regarding type of surfactant used and cholesterol concentration significantly affected both entrapment efficiency (%EE) and vesicle size. Span 80 proniosome-derived niosomes exhibited higher encapsulation efficiency and smaller particle size than those derived from span 20. Also, the effect of %EE and bioadhesive polymer type on in vitro drug release and in vivo performance of buccoadhesive tablets was investigated. Based on achievement of required in vitro release pattern (20-30% at 2h, 40-65% at 6h and 80-95% at 12h), in vivo swelling behavior, and in vivo adhesion time (>14 h) granisetron formulation (F19, 1.4 mg) comprising HPMC:carbopol 974P (7:3) and maltodextrin coated with the vesicular precursors span 80 and cholesterol (9:1) was chosen for in vivo study. In vivo pharmacokinetic study revealed higher bioavailability of buccal formulation relative to conventional oral formulation of granisetron (AUC0-∞ is 89.97 and 38.18 ng h/ml for buccal and oral formulation, respectively). A significantly lower and delayed Cmax (12.09±4.47 ng/ml, at 8h) was observed after buccal application compared to conventional oral tablet (31.66±10.15 ng/ml, at 0.5 h). The prepared provesicular buccoadhesive tablet of granisetron (F19) might help bypass hepatic first

  5. Preliminary Data Pipeline for SunRISE: Assessing the Performance of Space Based Radio Arrays

    Science.gov (United States)

    Hegedus, A. M.; Kasper, J. C.; Lazio, J.; Amiri, N.; Stuart, J.

    2017-12-01

    elliptical Gaussian, which we can compare directly to the input. We find that at the upper frequencies the phase noise can negatively affect performance of the array, but for the large majority of the tracking range of interest, SunRISE can sufficiently resolve the radio bursts to fulfill its science requirements and constrain Solar Energetic Particle acceleration and transport.

  6. Preliminary Axial Flow Turbine Design and Off-Design Performance Analysis Methods for Rotary Wing Aircraft Engines. Part 2; Applications

    Science.gov (United States)

    Chen, Shu-cheng, S.

    2009-01-01

    In this paper, preliminary studies on two turbine engine applications relevant to the tilt-rotor rotary wing aircraft are performed. The first case-study is the application of variable pitch turbine for the turbine performance improvement when operating at a substantially lower shaft speed. The calculations are made on the 75 percent speed and the 50 percent speed of operations. Our results indicate that with the use of the variable pitch turbines, a nominal (3 percent (probable) to 5 percent (hypothetical)) efficiency improvement at the 75 percent speed, and a notable (6 percent (probable) to 12 percent (hypothetical)) efficiency improvement at the 50 percent speed, without sacrificing the turbine power productions, are achievable if the technical difficulty of turning the turbine vanes and blades can be circumvented. The second casestudy is the contingency turbine power generation for the tilt-rotor aircraft in the One Engine Inoperative (OEI) scenario. For this study, calculations are performed on two promising methods: throttle push and steam injection. By isolating the power turbine and limiting its air mass flow rate to be no more than the air flow intake of the take-off operation, while increasing the turbine inlet total temperature (simulating the throttle push) or increasing the air-steam mixture flow rate (simulating the steam injection condition), our results show that an amount of 30 to 45 percent extra power, to the nominal take-off power, can be generated by either of the two methods. The methods of approach, the results, and discussions of these studies are presented in this paper.

  7. Alameda-Contra Costa Transit District (AC Transit) Fuel Cell Transit Buses: Preliminary Evaluation Results

    Energy Technology Data Exchange (ETDEWEB)

    Chandler, K.; Eudy, L.

    2007-03-01

    This report provides an evaluation of three prototype fuel cell-powered transit buses operating at AC Transit in Oakland, California, and six baseline diesel buses similar in design to the fuel cell buses.

  8. Experimental-demonstrative system for energy conversion using hydrogen fuel cell - preliminary results

    International Nuclear Information System (INIS)

    Stoenescu, D.; Stefanescu, I.; Patularu, I.; Culcer, M.; Lazar, R.E.; Carcadea, E.; Mirica, D. . E-mail address of corresponding author: daniela@icsi.ro; Stoenescu, D.)

    2005-01-01

    It is well known that hydrogen is the most promising solution of future energy, both for long and medium term strategies. Hydrogen can be produced using many primary sources (natural gas, methane, biomass, etc.), it can be burned or chemically react having a high yield of energy conversion, being a non-polluted fuel. This paper presents the preliminary results obtained by ICSI Rm. Valcea in an experimental-demonstrative conversion energy system made by a sequence of hydrogen purification units and a CO removing reactors until a CO level lower than 10ppm, that finally feeds a hydrogen fuel stack. (author)

  9. Impact of Interfacial Water Transport in PEMFCs on Cell Performance

    International Nuclear Information System (INIS)

    Kotaka, Toshikazu; Tabuchi, Yuichiro; Pasaogullari, Ugur; Wang, Chao-Yang

    2014-01-01

    Coupled cell performance evaluation, liquid water visualization by neutron radiography (NRG) and numerical modeling based on multiphase mixture (M2) model were performed with three types of GDMs: Micro Porous Layer (MPL) free; Carbon Paper (CP) with MPL; and CP free to investigate interfacial liquid water transport phenomena in PEMFCs and its effect on cell performance. The visualized results of MPL free GDM with different wettability of bi-polar plates (BPPs) showed hydrophilic BPP improved liquid water transport at the interface between CP and channel. Numerical modeling results indicated that this difference with BPP wettability was caused by the liquid water coverage difference on CP surface. Thus, controlling liquid water coverage is the one of the key strategies for improving cell performance. Additionally, liquid water distributions across the cell for three types of GDMs were compared and significant difference in liquid water content at the interface between Catalyst Layer (CL) and GDM was observed. Numerical modeling suggests this difference is influenced by the gap at the interface and that the MPL could minimize this effect. The CP free cell (i.e. only MPL) showed the best performance and the lowest liquid water content. There were multiple impacts of interfacial liquid water transport both at CL-GDM and GDM-channel interfaces. High hydrophobicity and fine structure of MPLs contributed to enhanced liquid water transport at GDM-channel interface and as a result reduced the liquid water coverage. At the same time, MPL improves contact at the CL-GDM interface in the same manner as seen in CP with MPL case. Thus, the CP free concept showed the best performance. It is suggested that the design of the interface between each component of the PEMFC has a great impact on cell performance and plays a significant role in achievement of high current density operation and cost reduction in FCEVs

  10. Preliminary study of steep pulse irreversible electroporation technology in human large cell lung cancer cell lines L9981

    Directory of Open Access Journals (Sweden)

    Song Zuoqing

    2013-01-01

    Full Text Available Our aim was to validate the effectiveness of steep pulse irreversible electroporation technology in human large cell lung cancer cells and to screen the optimal treatment of parameters for human large cell lung cancer cells. Three different sets of steep pulse therapy parameters were applied on the lung cancer cell line L9981. The cell line L9981 inhibition rate and proliferation capacity were detected by Vi-Cell vitality analysis and MTT. Steep pulsed irreversible electroporation technology for large cell lung cancer L9981 presents killing effects with various therapy parameters. The optimal treatment parameters are at a voltage amplitude of 2000V/cm, pulse width of 100μs, pulse frequency of 1 Hz, pulse number 10. With this group of parameters, steep pulse could have the best tumor cell-killing effects.

  11. Evaluation of the structural integrity of LMFBR equipment cell liners: results of preliminary investigations

    International Nuclear Information System (INIS)

    McAfee, W.J.; Sartory, W.K.

    1976-01-01

    The behavior of a plane wall segment of a prototype liquid-metal-cooled fast breeder reactor (LMFBR) cell under conditions of a postulated massive sodium spill was studied. Sodium-concrete reaction calculations were performed assuming an initial flaw existed in the liner such that high-temperature sodium could penetrate to the concrete underneath. Based on existing sodium-concrete reaction rate data, bounding values were established for the maximum energy release per unit volume of concrete. The potential effect of this energy release on the deformation of the liner material was determined. The temperature buildup in the liner and the pressure differential across the flaw in the liner were also studied. The transient thermal and structural responses of the steel liner and backup concrete were analyzed in detail using the inelastic computer code ANSYS. The literature on the mechanical, physical, and general behavior properties of concrete at high temperature was reviewed. This review emphasized the structural behavior of concrete and did not cover the sodium-concrete reaction

  12. Performance of planar heterojunction perovskite solar cells under light concentration

    Directory of Open Access Journals (Sweden)

    Aaesha Alnuaimi

    2016-11-01

    Full Text Available In this work, we present 2D simulation of planar heterojunction perovskite solar cells under high concentration using physics-based TCAD. The performance of planar perovskite heterojunction solar cells is examined up to 1000 suns. We analyze the effect of HTM mobility and band structure, surface recombination velocities at interfaces and the effect of series resistance under concentrated light. The simulation results revealed that the low mobility of HTM material limits the improvement in power conversation efficiency of perovskite solar cells under concentration. In addition, large band offset at perovskite/HTM interface contributes to the high series resistance. Moreover, losses due to high surface recombination at interfaces and the high series resistance deteriorate significantly the performance of perovskite solar cells under concentration.

  13. Performance of proton exchange membrane fuel cells at elevated temperature

    International Nuclear Information System (INIS)

    Shyu, Jin-Cherng; Hsueh, Kan-Lin; Tsau, Fanghei

    2011-01-01

    Highlights: → At 1 atm, cell has best performance (∼1300 mA/cm at 0.6 V) at 100 deg. C and RH = 100%. → The A value in Eq. increased with increases in the back pressure and RH. →R i dramatically decreased at back pressure of 1 atm. → At each RH, R i decreased and then increased as cell temperature increased at 1 atm. - Abstract: The polarization curves of a single PEMFC having a Nafion membrane fed with H 2 /O 2 with relative humidity (RH) of 35%, 70% and 100% were measured at cell temperatures ranging from 65 deg. C to 120 deg. C at back pressures of 0 atm and 1 atm, respectively. Measured results showed that the best cell performance at 0.6 V operated within 65-120 deg. C at zero back pressure was 1000 mA cm -2 at 65 deg. C and RH = 100%, while the best cell performance at 1 atm back pressure was 1300 mA cm -2 at 100 deg. C and RH = 100%. Based on the analysis of impedance data measured at anode and cathode humidification temperatures of 90 deg. C and cell temperature of 100 deg. C at back pressures of 0 and 1 atm (90-100p0 and 90-100p1), it could be found that the membrane resistance was reduced and the catalyst became more active as the back pressure increases. The present results showed that increasing back pressure was able to dramatically improve cell performance and the effect of the back pressure surpassed that of humidification in the internal resistance of cell.

  14. Full-Duplex MIMO Small-Cell Networks: Performance Analysis

    OpenAIRE

    Atzeni, Italo; Kountouris, Marios

    2015-01-01

    Full-duplex small-cell relays with multiple antennas constitute a core element of the envisioned 5G network architecture. In this paper, we use stochastic geometry to analyze the performance of wireless networks with full-duplex multiple-antenna small cells, with particular emphasis on the probability of successful transmission. To achieve this goal, we additionally characterize the distribution of the self-interference power of the full-duplex nodes. The proposed framework reveals useful ins...

  15. In Vivo Articular Cartilage Regeneration Using Human Dental Pulp Stem Cells Cultured in an Alginate Scaffold: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Manuel Mata

    2017-01-01

    Full Text Available Osteoarthritis is an inflammatory disease in which all joint-related elements, articular cartilage in particular, are affected. The poor regeneration capacity of this tissue together with the lack of pharmacological treatment has led to the development of regenerative medicine methodologies including microfracture and autologous chondrocyte implantation (ACI. The effectiveness of ACI has been shown in vitro and in vivo, but the use of other cell types, including bone marrow and adipose-derived mesenchymal stem cells, is necessary because of the poor proliferation rate of isolated articular chondrocytes. In this investigation, we assessed the chondrogenic ability of human dental pulp stem cells (hDPSCs to regenerate cartilage in vitro and in vivo. hDPSCs and primary isolated rabbit chondrocytes were cultured in chondrogenic culture medium and found to express collagen II and aggrecan. Both cell types were cultured in 3% alginate hydrogels and implanted in a rabbit model of cartilage damage. Three months after surgery, significant cartilage regeneration was observed, particularly in the animals implanted with hDPSCs. Although the results presented here are preliminary, they suggest that hDPSCs may be useful for regeneration of articular cartilage.

  16. In Vivo Articular Cartilage Regeneration Using Human Dental Pulp Stem Cells Cultured in an Alginate Scaffold: A Preliminary Study.

    Science.gov (United States)

    Mata, Manuel; Milian, Lara; Oliver, Maria; Zurriaga, Javier; Sancho-Tello, Maria; de Llano, Jose Javier Martin; Carda, Carmen

    2017-01-01

    Osteoarthritis is an inflammatory disease in which all joint-related elements, articular cartilage in particular, are affected. The poor regeneration capacity of this tissue together with the lack of pharmacological treatment has led to the development of regenerative medicine methodologies including microfracture and autologous chondrocyte implantation (ACI). The effectiveness of ACI has been shown in vitro and in vivo , but the use of other cell types, including bone marrow and adipose-derived mesenchymal stem cells, is necessary because of the poor proliferation rate of isolated articular chondrocytes. In this investigation, we assessed the chondrogenic ability of human dental pulp stem cells (hDPSCs) to regenerate cartilage in vitro and in vivo . hDPSCs and primary isolated rabbit chondrocytes were cultured in chondrogenic culture medium and found to express collagen II and aggrecan. Both cell types were cultured in 3% alginate hydrogels and implanted in a rabbit model of cartilage damage. Three months after surgery, significant cartilage regeneration was observed, particularly in the animals implanted with hDPSCs. Although the results presented here are preliminary, they suggest that hDPSCs may be useful for regeneration of articular cartilage.

  17. 2010 Survey on cell phone use while performing cardiopulmonary bypass.

    Science.gov (United States)

    Smith, T; Darling, E; Searles, B

    2011-09-01

    Cell phone use in the U.S. has increased dramatically over the past decade and text messaging among adults is now mainstream. In professions such as perfusion, where clinical vigilance is essential to patient care, the potential distraction of cell phones may be especially problematic. However, the extent of this as an issue is currently unknown. Therefore, the purpose of this study was to (1) determine the frequency of cell phone use in the perfusion community, and (2) to identify concerns and opinions among perfusionists regarding cell phone use. In October 2010, a link to a 19-question survey (surveymonkey.com) was posted on the AmSECT (PerfList) and Perfusion.com (PerfMail) forums. There were 439 respondents. Demographic distribution is as follows; Chief Perfusionist (30.5%), Staff Perfusionist (62.0%), and Other (7.5%), with age ranges of 20-30 years (14.2%), 30-40 years (26.5%), 40-50 years (26.7%), 50-60 years (26.7%), >60 years (5.9%). The use of a cell phone during the performance of cardiopulmonary bypass (CPB) was reported by 55.6% of perfusionists. Sending text messages while performing CPB was acknowledged by 49.2%, with clear generational differences detected when cross-referenced with age groups. For smart phone features, perfusionists report having accessed e-mail (21%), used the internet (15.1%), or have checked/posted on social networking sites (3.1%) while performing CPB. Safety concerns were expressed by 78.3% who believe that cell phones can introduce a potentially significant safety risk to patients. Speaking on a cell phone and text messaging during CPB are regarded as "always an unsafe practice" by 42.3% and 51.7% of respondents, respectively. Personal distraction by cell phone use that negatively affected performance was admitted by 7.3%, whereas witnessing another perfusionist distracted with phone/text while on CPB was acknowledged by 33.7% of respondents. This survey suggests that the majority of perfusionists believe cell phones raise

  18. Performance of Lithium Polymer Cells with Polyacrylonitrile based Electrolyte

    DEFF Research Database (Denmark)

    Perera, Kumudu; Dissanayake, M.A.K.L.; Skaarup, Steen

    2006-01-01

    The performance of lithium polymer cells fabricated with Polyacrylonitrile (PAN) based electrolytes was studied using cycling voltammetry and continuous charge discharge cycling. The electrolytes consisted of PAN, ethylene carbonate (EC), propylene carbonate (PC) and lithium...... trifluoromethanesulfonate (LiCF3SO3 – LiTF). The polymer electrode material was polypyrrole (PPy) doped with dodecyl benzene sulfonate (DBS). The cells were of the form, Li / PAN : EC : PC : LiCF3SO3 / PPy : DBS. Polymer electrodes of three different thicknesses were studied using cycling at different scan rates. All cells...

  19. The effect of liner hydraulic conductivity on disposal cell performance

    International Nuclear Information System (INIS)

    Yu, C.; Yuan, Y.C.; Chia, Y.P.

    1988-01-01

    Multilayered disposal cells are frequently used for the disposal of radioactive and hazardous wastes. These disposal cells consist of materials with different permeabilities that are placed in various thicknesses at the bottom as well as in the cover of the cell. Typically, a layer of permeable material is placed above a layer with low permeability; the permeable layer functions as a drainage/leachate collection system and the low-permeability layer functions as a migration barrier/liner. This paper analyzes the effects of infiltration through unsaturated soil liners on the long-term performance of the disposal cell. Based on the results of this study, it is concluded that the long-term performance of a disposal cell is dependent on a well-designed cell cover. The design should emphasize a cap with less permeable material to prevent water from infiltrating the disposal cell. An impermeable bottom liner is effective only in the short term; however, it can eventually result in saturation of the wastes and cause the bathtub effect over the long term

  20. Transcriptomic response of goat mammary epithelial cells to Mycoplasma agalactiae challenge – a preliminary study

    DEFF Research Database (Denmark)

    Ogorevc, Jernej; Mihevc, Sonja Prpar; Hedegaard, Jakob

    2015-01-01

    Mycoplasma agalactiae (Ma) is one of the main aetiological agents of intramammary infections in small ruminants, causing contagious agalactia. To better understand the underlying disease patterns a primary goat mammary epithelial cell (pgMEC) culture was established from the mammary tissue......, steroid metabolism, fatty acid metabolism, apoptosis signalling, transcription regulation, and cell cycle regulation. Based on the results we suggest that mammary epithelial cells in vivo contribute to the immune system by the induced expression of cytokines and other chemotactic agents, activation...

  1. Preliminary study on proteomic technique in radiobiological characteristics in nasopharyngeal carcinoma cell line

    International Nuclear Information System (INIS)

    Wang Hui; Yi Xuping; Hu Bingqiang; Zeng Liang; Liu Yisong; Liang Songping

    2007-01-01

    Objective: To examine the variation of protein expression in nasopharyngeal carcinoma cell lines with different biological characteristics and to identify the radiobiological associated proteins. Methods: Biological characteristics of 5-8F and 6-10B were compared by flow cytometry assay after irradiation. The total proteins of 5-8F and 6-10B were separated by immobilized pH gradient(IPG) IEF-SDS two-dimensional gel eleetrophoresis technique. The differentially expressed proteins were cut from the gel and digested into peptides for MALDI-TOF MS and the Q-TOF mass spectrometric analysis. Identification of protein was made through searching in protein sequence database. Protein expressions were examined by western blot and immunohistochemistry method. Results: Nine most differentially expressed proteins between 5-8F cell and 6-10B cell were identified, p73 and CK19 expression examined by western blot were conformal with that by proteomic method, p73 expression in 5-8F cell was higher than in 6-10B cell. CK19 expression in 6- 10B cell was higher than in 5-8F cell. Conclusion: Differentially expression of proteins exist in nasopharyngeal carcinoma cell lines with different biological characteristics. These proteins may be associated with cell radiobiological characteristic with the p73 as a potential biomarker. (authors)

  2. Intravenous mesenchymal stem cell therapy after recurrent laryngeal nerve injury: a preliminary study.

    Science.gov (United States)

    Lerner, Michael Z; Matsushita, Takashi; Lankford, Karen L; Radtke, Christine; Kocsis, Jeffery D; Young, Nwanmegha O

    2014-11-01

    Intravenous administration of mesenchymal stem cells (MSCs) has been recently shown to enhance functional recovery after stroke and spinal cord injury. The therapeutic properties of MSCs are attributed to their secretion of a variety of potent antiinflammatory and neurotrophic factors. We hypothesize that intravenous administration of MSCs after recurrent laryngeal nerve (RLN) injury in the rat may enhance functional recovery. Animal Research. Twelve 250-gram Sprague-Dawley rats underwent a controlled crush injury to the left RLN. After confirming postoperative vocal fold immobility, each rat was intravenously infused with either green fluorescent protein-expressing MSCs or control media in a randomized and blinded fashion. Videolaryngoscopy was performed weekly. The laryngoscopy video recordings were reviewed and rated by a fellowship-trained laryngologist who remained blinded to the intervention using a 0 to 3 scale. At 1 week postinjury, the MSC-infused group showed a trend for higher average functional recovery scores compared to the control group (2.2 vs 1.3), but it did not reach statistical significance (P value of 0.06). By 2 weeks, however, both groups exhibited complete return of function. These pilot data indicate that with complete nerve transection by crush injury of the RLN in rat, there is complete recovery of vocal fold mobility at 2 weeks. At 1 week postinjury, animals receiving intravenous infusion of MSCs showed a trend for greater functional recovery, suggesting a potential beneficial effect of MSCs; however, this did not reach statistical significance. Therefore, no definite conclusions can be drawn from these data and further study is required. N/A. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

  3. Thorium-Based Fuels Preliminary Lattice Cell Studies for Candu Reactors

    International Nuclear Information System (INIS)

    Margeanu, C.A.; Rizoiu, A.C.

    2009-01-01

    The choice of nuclear power as a major contributor to the future global energy needs must take into account acceptable risks of nuclear weapon proliferation, in addition to economic competitiveness, acceptable safety standards, and acceptable waste disposal options. Candu reactors offer a proven technology, safe and reliable reactor technology, with an interesting evolutionary potential for proliferation resistance, their versatility for various fuel cycles creating premises for a better utilization of global fuel resources. Candu reactors impressive degree of fuel cycle flexibility is a consequence of its channel design, excellent neutron economy, on-power refueling, and simple fuel bundle. These features facilitate the introduction and exploitation of various fuel cycles in Candu reactors in an evolutionary fashion. The main reasons for our interest in Thorium-based fuel cycles have been, globally, to extend the energy obtainable from natural Uranium and, locally, to provide a greater degree of energy self-reliance. Applying the once through Thorium (OTT) cycle in existing and advanced Candu reactors might be seen as an evaluative concept for the sustainable development both from the economic and waste management points of view. Two Candu fuel bundles project will be used for the proposed analysis, namely the Candu standard fuel bundle with 37 fuel elements and the CANFLEX fuel bundle with 43 fuel elements. Using the Canadian proposed scheme - loading mixed ThO 2 -SEU CANFLEX bundles in Candu 6 reactors - simulated at lattice cell level led to promising conclusions on operation at higher fuel burnups, reduction of the fissile content to the end of the cycle, minor actinide content reduction in the spent fuel, reduction of the spent fuel radiotoxicity, presence of radionuclides emitting strong gamma radiation for proliferation resistance benefit. The calculations were performed using the lattice codes WIMS and Dragon (together with the corresponding nuclear data

  4. Preliminary results in combined therapy (polychemotherapy and radiotherapy) of small cell bronchial cancer

    International Nuclear Information System (INIS)

    Gaertner, C.; Rjabuchin, J.S.; Michina, Z.P.; Motorina, L.I.

    1984-01-01

    The effective therapy of small cell lung cancer is the combination of polychemotherapy and radiation treatment. A randomized small cell lung cancer study of 141 patients revealed that with an agressive treatment more than 50 % complete remissions and nearly 90 % complete and partial remissions can be achieved by corresponding selection of patients. (author)

  5. Preliminary report of cells at risk at the bone surface in trabecular bone

    International Nuclear Information System (INIS)

    Jee, W.S.S.; Wronski, T.J.; Kimmel, D.B.; Dell, R.B.; Johnson, F.

    1975-01-01

    This is a report of some early work on the cells at risk portion of the dynamic microanatomical dosimetry program of the Bone Group. The cells lining the trabecular bone of thoracic vertebral bodies from beagles aged 568, 2942, 4117, 4277, 4629, and 4801 days were characterized. Histologic and sampling experience gained in this attempt indicates that further improvements are needed

  6. Performance analysis of solar cell arrays in concentrating light intensity

    International Nuclear Information System (INIS)

    Xu Yongfeng; Li Ming; Lin Wenxian; Wang Liuling; Xiang Ming; Zhang Xinghua; Wang Yunfeng; Wei Shengxian

    2009-01-01

    Performance of concentrating photovoltaic/thermal system is researched by experiment and simulation calculation. The results show that the I-V curve of the GaAs cell array is better than that of crystal silicon solar cell arrays and the exergy produced by 9.51% electrical efficiency of the GaAs solar cell array can reach 68.93% of the photovoltaic/thermal system. So improving the efficiency of solar cell arrays can introduce more exergy and the system value can be upgraded. At the same time, affecting factors of solar cell arrays such as series resistance, temperature and solar irradiance also have been analyzed. The output performance of a solar cell array with lower series resistance is better and the working temperature has a negative impact on the voltage in concentrating light intensity. The output power has a -20 W/V coefficient and so cooling fluid must be used. Both heat energy and electrical power are then obtained with a solar trough concentrating photovoltaic/thermal system. (semiconductor devices)

  7. Energy Harvesting From River Sediment Using a Microbial Fuel Cell: Preliminary Results

    Directory of Open Access Journals (Sweden)

    Philippe Namour

    2014-05-01

    Full Text Available We have built a sedimentary fuel cell or Sediment Microbial Fuel Cell (SMFC. The device works on the principle of microbial fuel cells by exploiting directly the energy contained in sedimentary organic matter. It converts in electricity the sediment potential, thanks to microorganisms able to waste electrons from their metabolism directly to a solid anode instead of their natural electron acceptors, such as oxygen or nitrate. The sediment microbial fuel cell was made of a non-corrodible anode (graphite buried in anoxic sediments layer and connected via an electrical circuit to a cathode installed in surface water. We present the first results of laboratory sedimentary fuel cell and a prototype installed in the river.

  8. Effect of localized polycrystalline silicon properties on solar cell performance

    Science.gov (United States)

    Leung, D.; Iles, P. A.; Hyland, S.; Kachare, A.

    1984-01-01

    Several forms of polycrystalline silicon, mostly from cast ingots, (including UCP, SILSO and HEM) were studied. On typical slices, localized properties were studied in two ways. Small area (about 2.5 sq mm) mesa diodes were formed, and localized photovoltaic properties were measured. Also a small area (about .015 sq mm) light spot was scanned across the cells; the light spot response was calibrated to measure local diffusion length directly. Using these methods, the effects of grain boundaries, or of intragrain imperfections were correlated with cell performance. Except for the fine grain portion of SILSO, grain boundaries played only a secondary role in determining cell performance. The major factor was intra-grain material quality and it varied with position in ingots and probably related to solidification procedure.

  9. Preliminary performance assessment for the Waste Isolation Pilot Plant, December 1992. Volume 5, Uncertainty and sensitivity analyses of gas and brine migration for undisturbed performance

    Energy Technology Data Exchange (ETDEWEB)

    1993-08-01

    Before disposing of transuranic radioactive waste in the Waste Isolation Pilot Plant (WIPP), the United States Department of Energy (DOE) must evaluate compliance with applicable long-term regulations of the United States Environmental Protection Agency (EPA). Sandia National Laboratories is conducting iterative performance assessments (PAs) of the WIPP for the DOE to provide interim guidance while preparing for a final compliance evaluation. This volume of the 1992 PA contains results of uncertainty and sensitivity analyses with respect to migration of gas and brine from the undisturbed repository. Additional information about the 1992 PA is provided in other volumes. Volume 1 contains an overview of WIPP PA and results of a preliminary comparison with 40 CFR 191, Subpart B. Volume 2 describes the technical basis for the performance assessment, including descriptions of the linked computational models used in the Monte Carlo analyses. Volume 3 contains the reference data base and values for input parameters used in consequence and probability modeling. Volume 4 contains uncertainty and sensitivity analyses with respect to the EPA`s Environmental Standards for the Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes (40 CFR 191, Subpart B). Finally, guidance derived from the entire 1992 PA is presented in Volume 6. Results of the 1992 uncertainty and sensitivity analyses indicate that, conditional on the modeling assumptions and the assigned parameter-value distributions, the most important parameters for which uncertainty has the potential to affect gas and brine migration from the undisturbed repository are: initial liquid saturation in the waste, anhydrite permeability, biodegradation-reaction stoichiometry, gas-generation rates for both corrosion and biodegradation under inundated conditions, and the permeability of the long-term shaft seal.

  10. Preliminary screening and identification of the hepatocarcinoma cell-binding peptide

    International Nuclear Information System (INIS)

    Zhu Xiaohua; Wu Hua

    2004-01-01

    Objective: To explore the feasibility of screening and isolating homing peptides that bind specifically, or preferentially, to hepatocarcinoma cells using phage display random peptide library and to develop a new peptide which may be potentially used as targeting delivery carrier in the biological targeted diagnosis or therapy for liver cancer. Methods: A 12-mer peptide phage display library was used to screen and isolate peptides that bind to human hepatocarcinoma cells, and four rounds of subtractive panning were carried out with the human hepatocarcinoma cell line HepG2 as the target. The affinities of selected phage clones for human hepatocarcinoma cells were determined with enzyme-linked immunosorbent assay (ELISA) and compared with that to human liver cell and other tumor cells of different tissue origins, respectively. In addition, the binding site in the tumor cells was observed with immunofluorescence analysis under confocal light microscopy. The amino acid sequences of phages that bind HepG2 specifically were deduced through DNA sequencing. Based on the results of DNA sequence, a 16-mer peptide (WH16) was designed and synthesized. Binding ability of the new peptide, WH16, was determined with competitive inhibition test. Results: After four rounds of panning, the phages that were bound to and internalized in human hepatocarcinoma cells were isolated. ELISA and immunofluorescence analysis confirmed the affinity of these phages for hepatocarcinoma cells. 56.67%(17/30) of the isolated phages displayed repeated sequence FLLEPHLMDTSM, and FLEP was defined as conservative motif . Binding of the selected phage to HepG2 cells was inhibited by synthesized peptide WH16, that strongly support that cellular binding of the phage is mediated through its displayed peptide, and WH16 can also bind to HepG2. Conclusions: It is feasible to screen and isolate homing peptides that bind specifically, or preferentially, to hepatocarcinoma cells using phage display random peptide

  11. Preliminary screening and identification of the hepatocarcinoma cell-binding peptide

    Energy Technology Data Exchange (ETDEWEB)

    Xiaohua, Zhu; Hua, Wu [Department of Nuclear Medicine, Tongji Hospital, Tongji Medical College, Huazhong Univ. of Science and Technology, Wuhan (China)

    2004-12-15

    Objective: To explore the feasibility of screening and isolating homing peptides that bind specifically, or preferentially, to hepatocarcinoma cells using phage display random peptide library and to develop a new peptide which may be potentially used as targeting delivery carrier in the biological targeted diagnosis or therapy for liver cancer. Methods: A 12-mer peptide phage display library was used to screen and isolate peptides that bind to human hepatocarcinoma cells, and four rounds of subtractive panning were carried out with the human hepatocarcinoma cell line HepG2 as the target. The affinities of selected phage clones for human hepatocarcinoma cells were determined with enzyme-linked immunosorbent assay (ELISA) and compared with that to human liver cell and other tumor cells of different tissue origins, respectively. In addition, the binding site in the tumor cells was observed with immunofluorescence analysis under confocal light microscopy. The amino acid sequences of phages that bind HepG2 specifically were deduced through DNA sequencing. Based on the results of DNA sequence, a 16-mer peptide (WH16) was designed and synthesized. Binding ability of the new peptide, WH16, was determined with competitive inhibition test. Results: After four rounds of panning, the phages that were bound to and internalized in human hepatocarcinoma cells were isolated. ELISA and immunofluorescence analysis confirmed the affinity of these phages for hepatocarcinoma cells. 56.67%(17/30) of the isolated phages displayed repeated sequence FLLEPHLMDTSM, and FLEP was defined as conservative motif . Binding of the selected phage to HepG2 cells was inhibited by synthesized peptide WH16, that strongly support that cellular binding of the phage is mediated through its displayed peptide, and WH16 can also bind to HepG2. Conclusions: It is feasible to screen and isolate homing peptides that bind specifically, or preferentially, to hepatocarcinoma cells using phage display random peptide

  12. Effects of ambient conditions on fuel cell vehicle performance

    Science.gov (United States)

    Haraldsson, K.; Alvfors, P.

    Ambient conditions have considerable impact on the performance of fuel cell hybrid vehicles. Here, the vehicle fuel consumption, the air compressor power demand, the water management system and the heat loads of a fuel cell hybrid sport utility vehicle (SUV) were studied. The simulation results show that the vehicle fuel consumption increases with 10% when the altitude increases from 0 m up to 3000 m to 4.1 L gasoline equivalents/100 km over the New European Drive Cycle (NEDC). The increase is 19% on the more power demanding highway US06 cycle. The air compressor is the major contributor to this fuel consumption increase. Its load-following strategy makes its power demand increase with increasing altitude. Almost 40% of the net power output of the fuel cell system is consumed by the air compressor at the altitude of 3000 m with this load-following strategy and is thus more apparent in the high-power US06 cycle. Changes in ambient air temperature and relative humidity effect on the fuel cell system performance in terms of the water management rather in vehicle fuel consumption. Ambient air temperature and relative humidity have some impact on the vehicle performance mostly seen in the heat and water management of the fuel cell system. While the heat loads of the fuel cell system components vary significantly with increasing ambient temperature, the relative humidity did not have a great impact on the water balance. Overall, dimensioning the compressor and other system components to meet the fuel cell system requirements at the minimum and maximum expected ambient temperatures, in this case 5 and 40 °C, and high altitude, while simultaneously choosing a correct control strategy are important parameters for efficient vehicle power train management.

  13. Dopamine transporter density by [99mTc]-TRODAT-1 SPECT and neurocognitive performance - a preliminary pilot study

    International Nuclear Information System (INIS)

    Shih, Ming C; Amaro, Edson Jr; Souza, Sayuri de E

    2006-01-01

    Introduction: Cognitive deficits are associated with functional impairment as well as with poor quality of life in Parkinson's disease (PD). The main brain alteration in PD is a progressive loss of nigrostriatal dopamine neurons. Both animal and human studies have demonstrated that basal ganglia dopamine system is important for cognitive and motor functioning. Dopamine transporter (DAT) PET and SPECT radiotracers have been successfully used to estimate, in vivo, dopamine neuronal loss in humans. Objectives: The present study is aimed to examine the relationship between cognitive impairment and striatal dopamine neuronal loss, as estimated by [ 99m Tc]-TRODAT-1 SPECT in PD patients. Methods: Fifteen PD patients were scanned with [ 99m Tc]-TRODAT-1 SPECT (Dual-Head-SPECT Hwakeye, GE). SPECT images were reconstructed with FBP and Butterworth filter 0,40c/px order 10. Regions of interest (ROIs) were striatum (STR) and occipital lobe (BKG nonspecific binding) and were delineated in 3-mm transaxials slices analyzed according to this formula BP=([STR-BKG]/BKG), where BP is the striatal DAT binding potential. Neurocognitive tests, including the Rey Auditory Verbal Learning Test, Wisconsin Card Sorting Test, Ravens Progressive Matrices, Digit Span and Tavis 3, were applied to all subjects by trained neuropsychologists. Results: Striatal DAT binding potential (BP) was negatively correlated with the RAVLT tests 4 (R= 0.57, p≤0.05) and 5 (R=0.57, p≤0.05), which evaluate verbal learning. Striatal DAT BP was also negatively correlated with the WCST learning item (R=0.54, p≤0.05) and the Tavis 3 items, action error (R=0.52, p≤0.05) and number of correct responses (R=0.47, p≤0.05). Conclusions: Although preliminary, the present findings suggest that striatal DAT loss is associated with a poorer performance on verbal learning and cognitive flexibility tasks. These results are in line with a previous study that examined healthy volunteers and found a relationship between

  14. Ventilation rates in classrooms and performances of students. Preliminary study on their association; Ventilatiedebieten in klaslokalen en prestaties van scholieren

    Energy Technology Data Exchange (ETDEWEB)

    Shaughnessy, R.J. [The University of Tulsa, Tulsa, OK (United States); Haverinen-Shaughnessy, U.; Nevalainen, A. [Department of Environmental Health, National Public Health Institute, Kuopio (Finland); Moschandreas, D. [Department of Chemical and Environmental Engineering, Illinois Institute of Technology, Chicago, IL (United States)

    2007-10-15

    Poor conditions leading to sub-standard indoor air quality (IAQ) in classrooms have been frequently cited in the literature over the past two decades. However, there is limited data linking poor IAQ in the classrooms to student performance. Whereas, it is assumed that poor IAQ results in reduced attendance and learning potential, and subsequent poor student performance, validating this hypothesis presents a challenge in today's school environment. This study explores the association between student performance on standardized aptitude tests that are administered to students on a yearly basis, to classroom carbon dioxide (CO2) concentrations, which provide a surrogate of ventilation being provided to each room. Data on classroom CO2 concentrations (over a 4-5h time span within a typical school day) were recorded in fifth grade classrooms in 54 elementary schools within a school district in the USA. Results from this preliminary study yield a significant (P<0.10) association between classroom-level ventilation rate and test results in math. They also indicate that non-linear effects may need to be considered for better representation of the association. A larger sample size is required in order to draw more definitive conclusions. [Dutch] Slechte omstandigheden die leiden tot een benedenmaatse binnenluchtkwaliteit (Indoor Air Quality - IAQ) in klaslokalen, zijn in de afgelopen twee decennia regelmatig aangehaald in de literatuur. Toch zijn er weinig onderzoeksresultaten waarin een verband wordt gelegd tussen een slechte IAQ in klaslokalen en de prestatie van scholieren. Er wordt verondersteld dat een slechte IAQ resulteert in een verminderde aanwezigheid en in een verminderd vermogen om te studeren, en daarop volgend in een slechte schoolprestatie. Om die reden zal het valideren van deze hypothese een uitdaging vormen in de schoolomgeving van dit moment. Dit onderzoek bestudeert het verband tussen de prestaties van scholieren en de concentraties koolstofdioxide

  15. Use of an adaptable cell culture kit for performing lymphocyte and monocyte cell cultures in microgravity

    Science.gov (United States)

    Hatton, J. P.; Lewis, M. L.; Roquefeuil, S. B.; Chaput, D.; Cazenave, J. P.; Schmitt, D. A.

    1998-01-01

    The results of experiments performed in recent years on board facilities such as the Space Shuttle/Spacelab have demonstrated that many cell systems, ranging from simple bacteria to mammalian cells, are sensitive to the microgravity environment, suggesting gravity affects fundamental cellular processes. However, performing well-controlled experiments aboard spacecraft offers unique challenges to the cell biologist. Although systems such as the European 'Biorack' provide generic experiment facilities including an incubator, on-board 1-g reference centrifuge, and contained area for manipulations, the experimenter must still establish a system for performing cell culture experiments that is compatible with the constraints of spaceflight. Two different cell culture kits developed by the French Space Agency, CNES, were recently used to perform a series of experiments during four flights of the 'Biorack' facility aboard the Space Shuttle. The first unit, Generic Cell Activation Kit 1 (GCAK-1), contains six separate culture units per cassette, each consisting of a culture chamber, activator chamber, filtration system (permitting separation of cells from supernatant in-flight), injection port, and supernatant collection chamber. The second unit (GCAK-2) also contains six separate culture units, including a culture, activator, and fixation chambers. Both hardware units permit relatively complex cell culture manipulations without extensive use of spacecraft resources (crew time, volume, mass, power), or the need for excessive safety measures. Possible operations include stimulation of cultures with activators, separation of cells from supernatant, fixation/lysis, manipulation of radiolabelled reagents, and medium exchange. Investigations performed aboard the Space Shuttle in six different experiments used Jurkat, purified T-cells or U937 cells, the results of which are reported separately. We report here the behaviour of Jurkat and U937 cells in the GCAK hardware in ground

  16. Preliminary research developing a theory of cell phone distraction and social relationships.

    Science.gov (United States)

    LaVoie, Noelle; Lee, Yi-Ching; Parker, James

    2016-01-01

    Motor vehicle crashes remain the leading cause of death and injury for people aged 5-34, accounting annually for over 3000 deaths, and 100 times as many injuries. It is well established that distracted driving, and cell phone use while driving in particular, pose significant crash risk to drivers. Research has demonstrated that drivers are well aware of this danger but over 90% of drivers report using a cell phone while driving. Given the likely role that social influence plays in how people use cell phones while driving surprisingly little research has been conducted investigating to whom drivers are talking or texting. We report the results of a national survey to determine who drivers are most likely to call or text when behind the wheel and compared these results with general cell phone calling and texting patterns as well as previous findings on the prevalence of calling and texting while driving. The results suggest that social distance is a key factor in cell phone use while driving: Teens are more likely to talk with parents, and adults are more likely to talk with spouses than general calling patterns would suggest. We discuss whether the purpose of calls made while driving, such as coordination, could help explain these patterns. We propose next steps for further examining the role social relationships play in cell phone use while driving to potentially reduce teen driver cell phone use by lowering the number of calls from parents. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Improved Performance in Mammalian Cell Perfusion Cultures by Growth Inhibition.

    Science.gov (United States)

    Wolf, Moritz K F; Closet, Aurélie; Bzowska, Monika; Bielser, Jean-Marc; Souquet, Jonathan; Broly, Hervé; Morbidelli, Massimo

    2018-05-21

    Mammalian cell perfusion cultures represent a promising alternative to the current fed-batch technology for the production of various biopharmaceuticals. Long-term operation at a fixed viable cell density (VCD) requires a viable culture and a constant removal of excessive cells. Product loss in the cell removing bleed stream deteriorates the process yield. In this study, the authors investigate the use of chemical and environmental growth inhibition on culture performance by either adding valeric acid (VA) to the production media or by reducing the culture temperature (33.0 °C) with respect to control conditions (36.5 °C, no VA). Low temperature significantly reduces cellular growth, thus, resulting in lower bleed rates accompanied by a reduced product loss of 11% compared to 26% under control conditions. Additionally, the cell specific productivity of the target protein improves and maintained stable leading to media savings per mass of product. VA shows initially an inhibitory effect on cellular growth. However, cells seemed to adapt to the presence of the inhibitor resulting in a recovery of the cellular growth. Cell cycle and Western blot analyses support the observed results. This work underlines the role of temperature as a key operating variable for the optimization of perfusion cultures. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Analysis of clonogenic human brain tumour cells: preliminary results of tumour sensitivity testing with BCNU

    Energy Technology Data Exchange (ETDEWEB)

    Rosenblum, M L; Dougherty, D A; Deen, D F; Hoshino, T; Wilson, C B [California Univ., San Francisco (USA). Dept. of Neurology

    1980-04-01

    Biopsies from 6 patients with glioblastoma multiforme were disaggregated and single cells were treated in vitro with various concentrations of 1,3-bis(2-chloroethyl)-1-nitroso urea (BCNU) and plated for cell survival. One patient's cells were sensitive to BCNU in vitro; after a single dose of BCNU her brain scan reverted to normal and she was clinically well. Five tumours demonstrated resistance in vitro. Three of these tumours progressed during the first course of chemotherapy with a nitrosourea and the patients died at 21/2, 4 and 81/2 months after operation. Two patients who showed dramatic responses to radiation therapy were considered unchanged after the first course of nitrosourea therapy (although one demonstrated tumour enlargement on brain scan). The correlation of in vitro testing of tumour cell sensitivity with actual patient response is encouraging enough to warrant further work to determine whether such tests should weigh in decisions on patient therapy.

  19. Preliminary report for the license of a hot cell that will be use in the technology development for the obtention of Mo-99

    International Nuclear Information System (INIS)

    Fucugauchi, L.A.; Millan S, S.; Lopez M, A.E.; Lopez C, R; Sanchez M, V.; Reynoso V, R.; Vera, A.

    1991-05-01

    A preliminary report for the license of a hot cell that will be used in the development of the technology for the obtaining of Mo-99 is presented. The following topics are also included: objective of the project, technical description, description of the prototype cell, handling of radioactive wastes, lists of equipment that will be used, risk analysis, curricula, quality assurance plan and an annex with the report on handling of radioactive wastes presented to the PAGD-IAEA. (Author)

  20. The Performance of a Direct Borohydride/Peroxide Fuel Cell Using Graphite Felts as Electrodes

    Directory of Open Access Journals (Sweden)

    Heng-Yi Lee

    2017-08-01

    Full Text Available A direct borohydride/peroxide fuel cell (DBPFC generates electrical power by recirculating liquid anolyte and catholyte between the stack and reservoirs, which is similar to the operation of flow batteries. To enhance the accessibility of the catalyst layer to the liquid anolyte/catholyte, graphite felts are employed as the porous diffusion layer of a single-cell DBPFC instead of carbon paper/cloth. The effects of the type of anode alkaline solution and operating conditions, including flow rate and temperature of the anolyte/catholyte, on DBPFC performance are investigated and discussed. The durability of the DBPFC is also evaluated by galvanostatic discharge at 0.1 A∙cm−2 for over 50 h. The results of this preliminary study show that a DBPFC with porous graphite electrodes can provide a maximum power density of 0.24 W∙cm−2 at 0.8 V. The performance of the DBPFC drops slightly after 50 h of operation; however, the discharge capacity shows no significant decrease.

  1. Performance Analysis and Development Strategies for Solid Oxide Fuel Cells

    International Nuclear Information System (INIS)

    Ivers-Tiffee, E; Leonide, A; Weber, A

    2011-01-01

    Solid oxide fuel cells (SOFC) are of great interest for a diverse range of applications. Within the past 10 years, an increase in power density by one order of magnitude, a lowering of the operating temperature by 200 K, and degradation rates lowered by a factor of 10 have been achieved on the cell and stack level. However, there is still room for further enhancement of the overall performance by suitably tailoring the cell components on a micro- and nanostructural level. The efficiency of the electrochemically active single cell is characterized by the linear ohmic losses within the electrolyte and by nonlinear polarization losses at the electrode-electrolyte interfaces. Both depend on material composition and operation conditions (temperature and time, fuel utilisation and gas composition). The area-specific resistance (ASR) is considered as the figure of merit for overall performance. ASR values of anode supported cells (ASC) were determined by means of impedance spectroscopy and subsequently separated into ohmic losses (mainly electrolyte) and nonlinear polarisation losses resulting from gas diffusion and activation polarization in the cathode and anode. The efficiencies of ASCs will be discussed for various material combinations in the temperature range of technological interest (between 550 deg. C and 850 deg. C).

  2. Solid oxide fuel cell performance under severe operating conditions

    DEFF Research Database (Denmark)

    Koch, Søren; Hendriksen, P.V.; Mogensen, Mogens Bjerg

    2006-01-01

    The performance and degradation of Solid Oxide Fuel Cells (SOFC) were studied under severe operating conditions. The cells studied were manufactured in a small series by ECN, in the framework of the EU funded CORE-SOFC project. The cells were of the anode-supported type with a double layer LSM...... cathode. They were operated at 750 °C or 850 °C in hydrogen with 5% or 50% water at current densities ranging from 0.25 A cm–2 to 1 A cm–2 for periods of 300 hours or more. The area specific cell resistance, corrected for fuel utilisation, ranged between 0.20 Ω cm2 and 0.34 Ω cm2 at 850 °C and 520 m......V, and between 0.51 Ω cm2 and 0.92 Ω cm2 at 750 °C and 520 mV. The degradation of cell performance was found to be low (ranging from 0 to 8%/1,000 hours) at regular operating conditions. Voltage degradation rates of 20 to 40%/1,000 hours were observed under severe operating conditions, depending on the test...

  3. Preliminary Identification of the Microbial Fuel Cell Bacteria Communities in Sewage

    International Nuclear Information System (INIS)

    Zain, S.M; Hashim, R.; Roslani, N.S.; Suja, F.; Basri, N.E.A.; Anuar, N.; Daud, W.R.W.

    2011-01-01

    This study aimed to determine the types of bacteria exist in wastewater that contribute to generate electricity and simultaneously remove carbon and nitrogen. The method used was Fluorescence In Situ Hybridization (FISH) to detect the bacteria group while Polymerase Chain Reaction (PCR) was used to confirm the observation made using FISH. A biochemical identification using BIOLOG GEN III MICROPLATE TM also was used . The samples were cultured on nutrient agar plate to identify the morphology of the bacteria. The result showed that 21 isolates from three different locations at the activated sludge treatment plant with six, eleven and four strains for raw sewage, aeration tank and returned activated sludge samples, respectively. Preliminary identification does not give a good match but only showed the existence of ammonia-oxidizing bacteria (FISH) and Kurtia Gibsoni (BIOLOG) from aeration tank : Bacillus sp (PCR) and Bacillus Pseudomycoides (BIOLOG) from returned activated sludge. The maximum power density generated using returned activated sludge was 9.053 mW/ cm 2 , with 26.8 % COD removal and 40 % TKN removal (author)

  4. A preliminary study of a miniature planar 6-cell PEMFC stack combined with a small hydrogen storage canister

    Science.gov (United States)

    Zhang, Xigui; Zheng, Dan; Wang, Tao; Chen, Cong; Cao, Jianyu; Yan, Jian; Wang, Wenming; Liu, Juanying; Liu, Haohan; Tian, Juan; Li, Xinxin; Yang, Hui; Xia, Baojia

    The fabrication and performance evaluation of a miniature 6-cell PEMFC stack based on Micro-Electronic-Mechanical-System (MEMS) technology is presented in this paper. The stack with a planar configuration consists of 6-cells in serial interconnection by spot welding one cell anode with another cell cathode. Each cell was made by sandwiching a membrane-electrode-assembly (MEA) between two flow field plates fabricated by a classical MEMS wet etching method using silicon wafer as the original material. The plates were made electrically conductive by sputtering a Ti/Pt/Au composite metal layer on their surfaces. The 6-cells lie in the same plane with a fuel buffer/distributor as their support, which was fabricated by the MEMS silicon-glass bonding technology. A small hydrogen storage canister was used as fuel source. Operating on dry H 2 at a 40 ml min -1 flow rate and air-breathing conditions at room temperature and atmospheric pressure, the linear polarization experiment gave a measured peak power of 0.9 W at 250 mA cm -2 for the stack and average power density of 104 mW cm -2 for each cell. The results suggested that the stack has reasonable performance benefiting from an even fuel supply. But its performance tended to deteriorate with power increase, which became obvious at 600 mW. This suggests that the stack may need some power assistance, from say supercapacitors to maintain its stability when operated at higher power.

  5. Brush Seals for Cryogenic Applications: Performance, Stage Effects, and Preliminary Wear Results in LN2 and LH2

    Science.gov (United States)

    Proctor, Margaret P.; Walker, James F.; Perkins, H. Douglas; Hoopes, Joan F.; Williamson, G. Scott

    1996-01-01

    Brush seals are compliant contacting seals and have significantly lower leakage than labyrinth seals in gas turbine applications. Their long life and low leakage make them candidates for use in rocket engine turbopumps. Brush seals, 50.8 mm (2 in.) in diameter with a nominal 127-micron (0.005-in.) radial interference, were tested in liquid nitrogen (LN2) and liquid hydrogen (LH2) at shaft speeds up to 35,000 and 65,000 rpm, respectively, and at pressure drops up to 1.21 MPa (175 psid) per brush. A labyrinth seal was also tested in liquid nitrogen to provide a baseline. The LN2 leakage rate of a single brush seal with an initial radial shaft interference of 127 micron (0.005 in.) measured one-half to one-third the leakage rate of a 12-tooth labyrinth seal with a radial clearance of 127 micron (0.005 in.). Two brushes spaced 7.21 micron (0.248 in.) apart leaked about one-half as much as a single brush, and two brushes tightly packed together leaked about three-fourths as much as a single brush. The maximum measured groove depth on the Inconel 718 rotor with a surface finish of 0.81 micron (32 microinch) was 25 micron (0.0010 in.) after 4.3 hr of shaft rotation in liquid nitrogen. The Haynes-25 bristles wore approximately 25 to 76 micron (0.001 to 0.003 in.) under the same conditions. Wear results in liquid hydrogen were significantly different. In liquid hydrogen the rotor did not wear, but the bristle material transferred onto the rotor and the initial 127 micron (0.005 in.) radial interference was consumed. Relatively high leakage rates were measured in liquid hydrogen. More testing is required to verify the leakage performance, to validate and calibrate analysis techniques, and to determine the wear mechanisms. Performance, staging effects, and preliminary wear results are presented.

  6. What Happens Inside a Fuel Cell? Developing an Experimental Functional Map of Fuel Cell Performance

    KAUST Repository

    Brett, Daniel J. L.

    2010-08-20

    Fuel cell performance is determined by the complex interplay of mass transport, energy transfer and electrochemical processes. The convolution of these processes leads to spatial heterogeneity in the way that fuel cells perform, particularly due to reactant consumption, water management and the design of fluid-flow plates. It is therefore unlikely that any bulk measurement made on a fuel cell will accurately represent performance at all parts of the cell. The ability to make spatially resolved measurements in a fuel cell provides one of the most useful ways in which to monitor and optimise performance. This Minireview explores a range of in situ techniques being used to study fuel cells and describes the use of novel experimental techniques that the authors have used to develop an \\'experimental functional map\\' of fuel cell performance. These techniques include the mapping of current density, electrochemical impedance, electrolyte conductivity, contact resistance and CO poisoning distribution within working PEFCs, as well as mapping the flow of reactant in gas channels using laser Doppler anemometry (LDA). For the high-temperature solid oxide fuel cell (SOFC), temperature mapping, reference electrode placement and the use of Raman spectroscopy are described along with methods to map the microstructural features of electrodes. The combination of these techniques, applied across a range of fuel cell operating conditions, allows a unique picture of the internal workings of fuel cells to be obtained and have been used to validate both numerical and analytical models. © 2010 Wiley-VCH Verlag GmbH& Co. KGaA, Weinheim.

  7. Performance of multi-junction cells due to illumination distribution across the cell surface

    International Nuclear Information System (INIS)

    Schultz, R.D.; Vorster, F.J; Dyk, E.E van

    2012-01-01

    This paper addresses the influence of illumination distribution on the performance of a high concentration photovoltaic (HCPV) module. CPV systems comprise of optical elements as well as mechanical tracking to concentrate the solar flux onto the solar receiver as well as to keep the system on track with the sun. The performance of the subcells of the multi-junction concentrator cell depends on the optical alignment of the system. Raster scanning of the incident intensity in the optical plane of the receiver and corresponding I–V measurements were used to investigate the influence of illumination distribution on performance. The results show that the illumination distribution that differs between cells does affect the performance of the module. The performance of the subcells of the multi-junction concentrator cell also depends on the optical alignment of the system.

  8. Performance of multi-junction cells due to illumination distribution across the cell surface

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, R.D., E-mail: s206029578@live.nmmu.ac.za [Nelson Mandela University, Physics Department, P.O. Box 77000, 6031, Port Elizabeth (South Africa); Vorster, F.J; Dyk, E.E van [Nelson Mandela University, Physics Department, P.O. Box 77000, 6031, Port Elizabeth (South Africa)

    2012-05-15

    This paper addresses the influence of illumination distribution on the performance of a high concentration photovoltaic (HCPV) module. CPV systems comprise of optical elements as well as mechanical tracking to concentrate the solar flux onto the solar receiver as well as to keep the system on track with the sun. The performance of the subcells of the multi-junction concentrator cell depends on the optical alignment of the system. Raster scanning of the incident intensity in the optical plane of the receiver and corresponding I-V measurements were used to investigate the influence of illumination distribution on performance. The results show that the illumination distribution that differs between cells does affect the performance of the module. The performance of the subcells of the multi-junction concentrator cell also depends on the optical alignment of the system.

  9. Interfacial Layer Engineering for Performance Enhancement in Polymer Solar Cells

    Directory of Open Access Journals (Sweden)

    Hao Zeng

    2015-02-01

    Full Text Available Improving power conversion efficiency and device performance stability is the most critical challenge in polymer solar cells for fulfilling their applications in industry at large scale. Various methodologies have been developed for realizing this goal, among them interfacial layer engineering has shown great success, which can optimize the electrical contacts between active layers and electrodes and lead to enhanced charge transport and collection. Interfacial layers also show profound impacts on light absorption and optical distribution of solar irradiation in the active layer and film morphology of the subsequently deposited active layer due to the accompanied surface energy change. Interfacial layer engineering enables the use of high work function metal electrodes without sacrificing device performance, which in combination with the favored kinetic barriers against water and oxygen penetration leads to polymer solar cells with enhanced performance stability. This review provides an overview of the recent progress of different types of interfacial layer materials, including polymers, small molecules, graphene oxides, fullerene derivatives, and metal oxides. Device performance enhancement of the resulting solar cells will be elucidated and the function and operation mechanism of the interfacial layers will be discussed.

  10. Elective brain irradiation in patients with small-cell carcinoma of the lung: preliminary report

    International Nuclear Information System (INIS)

    Katsenis, A.T.; Karpasitis, N.; Giannakakis, D.; Maragoudakis, N.; Kiparissiadis, P.

    1982-01-01

    The brain is a common site of metastases in small-cell carcinoma of the lung. Prophylactic brain irradiation with doses of 4000-4500 rads in 3-4 weeks appears to decrease the occurrence of brain metastases although it does not prevent this completely. In a group of patients with small-cell carcinoma of the lung and without evidence of brain metastases, the authors review the site and extent of the primary, the methods of treatment, the techniques of brain irradiation, and the relapses rate in relation to the status of the primary and the rate of brain metastases in another group without prophylactic brain irradiation. They further attempt to investigate combined modalities of treatment which would prolong life and prevent neurological complications in the small number of long survivors with small-cell carcinoma of the lung. (Auth.)

  11. Purification, crystallization and preliminary crystallographic analysis of the SH2 domain of IL-2-inducible T-cell kinase

    International Nuclear Information System (INIS)

    Joseph, Raji E.; Ginder, Nathaniel D.; Hoy, Julie A.; Nix, Jay C.; Honzatko, Richard B.; Andreotti, Amy H.

    2011-01-01

    Crystallization conditions are described for the cis- and trans-imide bond-containing SH2 domain of IL-2-inducible T-cell kinase. Proline is a unique amino acid owing to the relatively small energy difference between the cis and trans conformations of its peptide bond. The X–Pro imide bond readily undergoes cis–trans isomerization in the context of short peptides as well as some proteins. However, the direct detection of cis–trans proline isomerization in folded proteins is technically challenging. NMR spectroscopy is well suited to the direct detection of proline isomerization in folded proteins. It is less clear how well X-ray crystallography can reveal this conformational exchange event in folded proteins. Conformational heterogeneity owing to cis–trans proline isomerization in the Src homology 2 (SH2) domain of the IL-2-inducible T-cell kinase (ITK) has been extensively characterized by NMR. Using the ITK SH2 domain as a test system, an attempt was made to determine whether proline isomerization could be detected in a crystal structure of the ITK SH2 domain. As a first step towards this goal, the purification, crystallization and preliminary characterization of the ITK SH2 domain are described

  12. Light-induced performance increase of silicon heterojunction solar cells

    KAUST Repository

    Kobayashi, Eiji; De Wolf, Stefaan; Levrat, Jacques; Christmann, Gabriel; Descoeudres, Antoine; Nicolay, Sylvain; Despeisse, Matthieu; Watabe, Yoshimi; Ballif, Christophe

    2016-01-01

    Silicon heterojunction solar cells consist of crystalline silicon (c-Si) wafers coated with doped/intrinsic hydrogenated amorphous silicon (a-Si:H) bilayers for passivating-contact formation. Here, we unambiguously demonstrate that carrier injection either due to light soaking or (dark) forward-voltage bias increases the open circuit voltage and fill factor of finished cells, leading to a conversion efficiency gain of up to 0.3% absolute. This phenomenon contrasts markedly with the light-induced degradation known for thin-film a-Si:H solar cells. We associate our performance gain with an increase in surface passivation, which we find is specific to doped a-Si:H/c-Si structures. Our experiments suggest that this improvement originates from a reduced density of recombination-active interface states. To understand the time dependence of the observed phenomena, a kinetic model is presented.

  13. Performance evaluation of direct methanol fuel cells for portable applications

    Energy Technology Data Exchange (ETDEWEB)

    Rashidi, R.; Dincer, I.; Naterer, G.F. [Faculty of Engineering and Applied Science, University of Ontario Institute of Technology, 2000 Simcoe Street North, Oshawa, Ontario (Canada); Berg, P. [Faculty of Science, University of Ontario Institute of Technology, 2000 Simcoe Street North, Oshawa, Ontario (Canada)

    2009-02-15

    This study examines the feasibility of powering a range of portable devices with a direct methanol fuel cell (DMFC). The analysis includes a comparison between a Li-ion battery and DMFC to supply the power for a laptop, camcorder and a cell phone. A parametric study of the systems for an operational period of 4 years is performed. Under the assumptions made for both the Li-ion battery and DMFC system, the battery cost is lower than the DMFC during the first year of operation. However, by the end of 4 years of operational time, the DMFC system would cost less. The weight and cost comparisons show that the fuel cell system occupies less space than the battery to store a higher amount of energy. The weight of both systems is almost identical. Finally, the CO{sub 2} emissions can be decreased by a higher exergetic efficiency of the DMFC, which leads to improved sustainability. (author)

  14. Light-induced performance increase of silicon heterojunction solar cells

    KAUST Repository

    Kobayashi, Eiji

    2016-10-11

    Silicon heterojunction solar cells consist of crystalline silicon (c-Si) wafers coated with doped/intrinsic hydrogenated amorphous silicon (a-Si:H) bilayers for passivating-contact formation. Here, we unambiguously demonstrate that carrier injection either due to light soaking or (dark) forward-voltage bias increases the open circuit voltage and fill factor of finished cells, leading to a conversion efficiency gain of up to 0.3% absolute. This phenomenon contrasts markedly with the light-induced degradation known for thin-film a-Si:H solar cells. We associate our performance gain with an increase in surface passivation, which we find is specific to doped a-Si:H/c-Si structures. Our experiments suggest that this improvement originates from a reduced density of recombination-active interface states. To understand the time dependence of the observed phenomena, a kinetic model is presented.

  15. A preliminary investigation into the prevalence and prediction of problematic cell phone use.

    Science.gov (United States)

    Smetaniuk, Peter

    2014-03-01

    Likening mobile phone use dependency to the classification of excessive behaviors may be necessarily equivalent in seriousness to previously established addictions such as problematic computing or excessive gambling. The aim of the study explores into the behavior of excessive use of mobile phones as a pathological behavior. Two studies investigated criteria for problematic mobile phone usage by examining student (Study 1, N = 301) and nonstudent (Study 2, N = 362) responses to a set of adapted mobile phone addiction inventories. Study 1 investigated cell phone addiction inventories as constructs designed to measure problematic cell phone use. Additionally, Study 2 sought to predict age, depression, extraversion, emotional stability, impulse control, and self-esteem as independent variables that augment respondents' perceptions of problematic use. The results from Study 1 and Study 2 indicate that 10 to 25% of the participants tested exhibited problematic cell phone usage. Additionally, age, depression, extraversion, and low impulse control are the most suitable predictors for problematic use. The results of the two studies indicate that problematic mobile phone use does occur and ought to be taken seriously by the psychological community. Presently, there is limited data providing conclusive evidence for a comprehensible categorization of cell phone addiction, as well as a unified explanatory model specific to problematic mobile phone use. Studies such as this one may contribute substantial findings, adding scientific significance, and offering a valuable submission for the ongoing progress of creating intervention frameworks relative to "virtual addictions".

  16. A preliminary investigation into the prevalence and prediction of problematic cell phone use

    Science.gov (United States)

    Smetaniuk, Peter

    2014-01-01

    Background and aims: Likening mobile phone use dependency to the classification of excessive behaviors may be necessarily equivalent in seriousness to previously established addictions such as problematic computing or excessive gambling. The aim of the study explores into the behavior of excessive use of mobile phones as a pathological behavior. Methods: Two studies investigated criteria for problematic mobile phone usage by examining student (Study 1, N = 301) and nonstudent (Study 2, N = 362) responses to a set of adapted mobile phone addiction inventories. Study 1 investigated cell phone addiction inventories as constructs designed to measure problematic cell phone use. Additionally, Study 2 sought to predict age, depression, extraversion, emotional stability, impulse control, and self-esteem as independent variables that augment respondents’ perceptions of problematic use. Results: The results from Study 1 and Study 2 indicate that 10 to 25% of the participants tested exhibited problematic cell phone usage. Additionally, age, depression, extraversion, and low impulse control are the most suitable predictors for problematic use. Conclusions: The results of the two studies indicate that problematic mobile phone use does occur and ought to be taken seriously by the psychological community. Presently, there is limited data providing conclusive evidence for a comprehensible categorization of cell phone addiction, as well as a unified explanatory model specific to problematic mobile phone use. Studies such as this one may contribute substantial findings, adding scientific significance, and offering a valuable submission for the ongoing progress of creating intervention frameworks relative to “virtual addictions”. PMID:25215213

  17. Novel Desaturation Cell to Quantify Gushing Intensity: A Preliminary Study on Model Solutions

    Czech Academy of Sciences Publication Activity Database

    Novák, Pavel; Poštulková, Michaela; Růžička, Marek; Brányik, T.

    2015-01-01

    Roč. 73, č. 2 (2015), s. 185-189 ISSN 0361-0470 R&D Projects: GA MŠk(CZ) LD13018 Institutional support: RVO:67985858 Keywords : gushing * desaturation cell * gushing matrix Subject RIV: EI - Biotechnology ; Bionics Impact factor: 0.492, year: 2015

  18. PRELIMINARY CLINICAL RESULTS WITH LIPOASPIRATE STROMAL VASCULAR CELL FRACTION IN TREATMENT OF PATIENTS WITH KNEE OSTEOARTHRITIS

    Directory of Open Access Journals (Sweden)

    E. Ya. Shevela

    2017-01-01

    Full Text Available The paper presents results of clinical application of autologous stromal-vascular fraction (SVF cells in patients with degenerative osteoarthritis (OA of the knee, grade II and III (Kellgren–Lawrence scale.We recruited six patients with knee OA (3 men and 3 women; median age 64 years with mean disease duration of 7 years. All the patients were administered a single intra-articular injection of autologous nucleated SVF cells at an average dose of 16.8±0.9 × 106 per joint (a total of 11 joints. The patients did not experience any serious side effects (allergic, toxic or inflammatory related to the knee injection. Patient surveys at 1 month after SVF administration revealed a decrease in the severity of pain, as measured by a visual analog scale (VAS and a specialized 100-point scale KOOS (subscale "pain" (p < 0.05 on both scales. Moreover, the patients reported improvement in the joint functions and quality of life related to affected joints on a KOOS scale (p < 0.05. These positive clinical changes persisted during 6 month follow up. Significant improvements were noted in ultrasound findings, with increased thickness of the cartilage layer at 3 months (in 73% of cases and at 6 months (in 82%. Our pilot study demonstrated the safety and tolerability of intra-articular injection of autologous SVF cells in patients with moderate to severe OA. The results obtained also indicate a significant antiinflammatory effect of autologous adipose tissue SVF cells, which is manifested at the early stages of cell therapy. Our further investigations will be focused on exploring the SVF stimulatory effects on regeneration of damaged joints.

  19. Analysis performance of proton exchange membrane fuel cell (PEMFC)

    Science.gov (United States)

    Mubin, A. N. A.; Bahrom, M. H.; Azri, M.; Ibrahim, Z.; Rahim, N. A.; Raihan, S. R. S.

    2017-06-01

    Recently, the proton exchange membrane fuel cell (PEMFC) has gained much attention to the technology of renewable energy due to its mechanically ideal and zero emission power source. PEMFC performance reflects from the surroundings such as temperature and pressure. This paper presents an analysis of the performance of the PEMFC by developing the mathematical thermodynamic modelling using Matlab/Simulink. Apart from that, the differential equation of the thermodynamic model of the PEMFC is used to explain the contribution of heat to the performance of the output voltage of the PEMFC. On the other hand, the partial pressure equation of the hydrogen is included in the PEMFC mathematical modeling to study the PEMFC voltage behaviour related to the input variable input hydrogen pressure. The efficiency of the model is 33.8% which calculated by applying the energy conversion device equations on the thermal efficiency. PEMFC’s voltage output performance is increased by increasing the hydrogen input pressure and temperature.

  20. Improving the photovoltaic performance of perovskite solar cells with acetate

    Science.gov (United States)

    Zhao, Qian; Li, G. R.; Song, Jian; Zhao, Yulong; Qiang, Yinghuai; Gao, X. P.

    2016-01-01

    In an all-solid-state perovskite solar cell, methylammonium lead halide film is in charge of generating photo-excited electrons, thus its quality can directly influence the final photovoltaic performance of the solar cell. This paper accentuates a very simple chemical approach to improving the quality of a perovskite film with a suitable amount of acetic acid. With introduction of acetate ions, a homogeneous, continual and hole-free perovskite film comprised of high-crystallinity grains is obtained. UV-visible spectra, steady-state and time-resolved photoluminescence (PL) spectra reveal that the obtained perovskite film under the optimized conditions shows a higher light absorption, more efficient electron transport, and faster electron extraction to the adjoining electron transport layer. The features result in the optimized perovskite film can provide an improved short-circuit current. The corresponding solar cells with a planar configuration achieves an improved power conversion efficiency of 13.80%, and the highest power conversion efficiency in the photovoltaic measurements is up to 14.71%. The results not only provide a simple approach to optimizing perovskite films but also present a novel angle of view on fabricating high-performance perovskite solar cells. PMID:27934924

  1. Improving the photovoltaic performance of perovskite solar cells with acetate.

    Science.gov (United States)

    Zhao, Qian; Li, G R; Song, Jian; Zhao, Yulong; Qiang, Yinghuai; Gao, X P

    2016-12-09

    In an all-solid-state perovskite solar cell, methylammonium lead halide film is in charge of generating photo-excited electrons, thus its quality can directly influence the final photovoltaic performance of the solar cell. This paper accentuates a very simple chemical approach to improving the quality of a perovskite film with a suitable amount of acetic acid. With introduction of acetate ions, a homogeneous, continual and hole-free perovskite film comprised of high-crystallinity grains is obtained. UV-visible spectra, steady-state and time-resolved photoluminescence (PL) spectra reveal that the obtained perovskite film under the optimized conditions shows a higher light absorption, more efficient electron transport, and faster electron extraction to the adjoining electron transport layer. The features result in the optimized perovskite film can provide an improved short-circuit current. The corresponding solar cells with a planar configuration achieves an improved power conversion efficiency of 13.80%, and the highest power conversion efficiency in the photovoltaic measurements is up to 14.71%. The results not only provide a simple approach to optimizing perovskite films but also present a novel angle of view on fabricating high-performance perovskite solar cells.

  2. High Performance Nano-Ceria Electrodes for Solid Oxide Cells

    DEFF Research Database (Denmark)

    Graves, Christopher R.; Martinez Aguilera, Lev; Sudireddy, Bhaskar Reddy

    2016-01-01

    forming the active surfaces on a porous backbone with embedded electronic current collector material, yielding one of the highest performances reported for an electrode that operates either on fuel or oxidant. The second is a nano-Ce0.9Gd0.1O2-δ thin film prepared by spin-coating, which provides......In solid oxide electrochemical cells, the conventional Ni-based fuel-electrodes provide high electrocatalytic activity but they are often a major source of long-term performance degradation due to carbon deposition, poisoning of reaction sites, Ni mobility, etc. Doped-ceria is a promising mixed...

  3. Device Engineering Towards Improved Tin Sulfide Solar Cell Performance and Performance Reproducibility

    Energy Technology Data Exchange (ETDEWEB)

    Steinmann, Vera; Chakraborty, Rupak; Rekemeyer, Paul; Siol, Sebastian; Martinot, Loic; Polizzotti, Alex; Yang, Chuanxi; Hartman, Katy; Gradecak, Silvija; Zakutayev, Andriy; Gordon, Roy G.; Buonassisi, Tonio

    2016-11-21

    As novel absorber materials are developed and screened for their photovoltaic (PV) properties, the challenge remains to rapidly test promising candidates in high-performing PV devices. There is a need to engineer new compatible device architectures, including the development of novel transparent conductive oxides and buffer layers. Here, we consider the two approaches of a substrate-style and a superstrate-style device architecture for novel thin-film solar cells. We use tin sulfide as a test absorber material. Upon device engineering, we demonstrate new approaches to improve device performance and performance reproducibility.

  4. Method to improve reliability of a fuel cell system using low performance cell detection at low power operation

    Science.gov (United States)

    Choi, Tayoung; Ganapathy, Sriram; Jung, Jaehak; Savage, David R.; Lakshmanan, Balasubramanian; Vecasey, Pamela M.

    2013-04-16

    A system and method for detecting a low performing cell in a fuel cell stack using measured cell voltages. The method includes determining that the fuel cell stack is running, the stack coolant temperature is above a certain temperature and the stack current density is within a relatively low power range. The method further includes calculating the average cell voltage, and determining whether the difference between the average cell voltage and the minimum cell voltage is greater than a predetermined threshold. If the difference between the average cell voltage and the minimum cell voltage is greater than the predetermined threshold and the minimum cell voltage is less than another predetermined threshold, then the method increments a low performing cell timer. A ratio of the low performing cell timer and a system run timer is calculated to identify a low performing cell.

  5. Lithium alloy-thionyl chloride cells - Performance and safety aspects

    Science.gov (United States)

    Peled, E.; Lombardi, A.; Schlaikjer, C. R.

    1983-06-01

    It is pointed out that the lithium-thionyl chloride cell has the highest energy density among all the commercially available batteries. The low rate, AA-bobbin cathode cell has been in the marketplace for several years, while the wound or spiral electrode cell is still in the stage of development. The main reason for this are safety problems. These problems are related to the very high reactivity of lithium toward thionyl chloride and the rather low melting point of lithium (180.5 C). The practical stability of the system depends on an LiCl-passivating layer which forms spontaneously on the immersion of the lithium in the electrolyte. This layer serves as a solid electrolyte interphase (SEI). Under certain extreme conditions, however, the SEI can be damaged in such a way that an explosion of the cell occurs. The present investigation is concerned with the reduction of the short-circuit current and the improvement of the safety performance of the cell by the use of special, treated lithium alloys.

  6. A Preliminary Study of Europium Uptake by Yeast Cells. The Case of Kluveromyces Marxianus

    International Nuclear Information System (INIS)

    Anagnostopoulos, V.; Symeopoulos, B.

    2008-01-01

    The objective of the present work is an exploration of a cost effective recovery of lanthanides, either for minimizing the industrial processes losses, or for reasons related to Radioactive Waste Management. Specifically, the uptake of europium from aqueous solutions by Kluveromyces marxianus cells was studied. Moreover, this biotechnological approach turns out to be environmental friendly, considering that cells of Kluveromyces marxianus are readily available as wastes from food fermentation industries. Europium [ 152 Eu+ 154 Eu]-labelled solutions were used providing better accuracy and reproducibility of measurements, mainly in low concentration range. The effect of pH, contact time and europium initial concentration were investigated. Adsorption data were fitted to Langmuir and Freundlich sorption models and Scatchard plots were used to reveal the existence of at least two types of binding sites

  7. Transcriptomic response of goat mammary epithelial cells to Mycoplasma agalactiae challenge – a preliminary study

    DEFF Research Database (Denmark)

    Ogorevc, Jernej; Mihevc, Sonja Prpar; Hedegaard, Jakob

    2015-01-01

    Mycoplasma agalactiae (Ma) is one of the main aetiological agents of intramammary infections in small ruminants, causing contagious agalactia. To better understand the underlying disease patterns a primary goat mammary epithelial cell (pgMEC) culture was established from the mammary tissue and ch....... Additionally, the results represent comprehensive goat mammary transcriptome information and demonstrate the applicability of the comparative genomics approach for annotation of goat data, using transcriptome information of a closely related species (Bos taurus) as a reference....

  8. A preliminary parametric performance assessment for the disposal of alpha-contaminated mixed low-level waste stored at the Idaho National Engineering Laboratory

    International Nuclear Information System (INIS)

    Smith, T.H.; Anderson, G.L.; Myers, J.

    1995-01-01

    A preliminary parametric performance assessment (PA) has been performed of potential waste disposal systems for alpha-contaminated mixed low-level waste (ALLW) currently stored at the Idaho National Engineering Laboratory. The radionuclide-confinement performance of treated ALLW in various final waste forms, in various disposal locations, and under various assumptions was evaluated. Compliance with performance objectives was assessed for the undisturbed waste scenario and for intrusion scenarios. Some combinations of final waste form, disposal site, and environmental transport assumptions lead to calculated does that comply with the performance objectives, while others do not. The results will help determine the optimum degree of ALLW immobilization to satisfy the performance objectives while minimizing cost

  9. Immunotropic potency of microwave fields: preliminary studies on immunocompetent cells exposed in vitro

    International Nuclear Information System (INIS)

    Stankiewicz, W.; Dabrowski, M.P.; Sobiczewska, E.; Kubacki, R.; Szmigielski, S.

    2006-01-01

    Exposure in radiofrequency (RF) and microwave (MW) fields can influence the function of the immune system, but the data available on the immunotropic potency of RF/MW radiation are still full of uncertainties and controversies. In the available literature there exist no reports on complex assessment of function and responsiveness of the immune system. All investigations have been aimed to evaluate selected, fragmentary reaction of the system and/or functional response of immunocompetent cells in RF/MW-exposed subjects. However, at the present state of knowledge it is not possible to conclude about the possible immunotropic potencies of RF/MW radiation. The undisturbed defensive, tolerogenic, and proregenerative activities of the immune system are commonly recognised as one of the most important homeostatic functions of the organism. Thus, basic immunoregulatory activities which can be observed and precisely quantified in microcultures of immune cells separated from the human blood, represent a unique and objective model for the investigation of possible immunotropic effects of electromagnetic fields (EMFs). To determine the potential immunomodulatory influences of EMFs, the immunotropic effects of pulse modulated microwave (1300 MHz) were investigated in the cultures of blood mononuclear cells from sixteen healthy donors

  10. Single Cell Confocal Raman Spectroscopy of Human Osteoarthritic Chondrocytes: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Rajesh Kumar

    2015-04-01

    Full Text Available A great deal of effort has been focused on exploring the underlying molecular mechanism of osteoarthritis (OA especially at the cellular level. We report a confocal Raman spectroscopic investigation on human osteoarthritic chondrocytes. The objective of this investigation is to identify molecular features and the stage of OA based on the spectral signatures corresponding to bio-molecular changes at the cellular level in chondrocytes. In this study, we isolated chondrocytes from human osteoarthritic cartilage and acquired Raman spectra from single cells. Major spectral differences between the cells obtained from different International Cartilage Repair Society (ICRS grades of osteoarthritic cartilage were identified. During progression of OA, a decrease in protein content and an increase in cell death were observed from the vibrational spectra. Principal component analysis and subsequent cross-validation was able to associate osteoarthritic chondrocytes to ICRS Grade I, II and III with specificity 100.0%, 98.1%, and 90.7% respectively, while, sensitivity was 98.6%, 82.8%, and 97.5% respectively. The overall predictive efficiency was 92.2%. Our pilot study encourages further use of Raman spectroscopy as a noninvasive and label free technique for revealing molecular features associated with osteoarthritic chondrocytes.

  11. l-Ergothioneine Protects Skin Cells against UV-Induced Damage—A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Karolina Bazela

    2014-03-01

    Full Text Available Many changes related to aging at the cellular level may be due to the physiological condition of mitochondria. One of the most common types of damage of mtDNA is the so-called “common deletion” referring to a deletion of 4977 base pairs. In the skin cells this phenomenon probably is caused by oxidative damage of mtDNA induced by UV. The present study was aimed at evaluating the effect of the antioxidant l-ergothioneine on UV-induced damage in skin cells. The effect of l-ergothioneine on the reduced glutathione level was studied. The presence of the “common deletion” in human fibroblasts irradiated with UVA and treated with l-ergothioneine was evaluated by a polymerase chain reaction. We have demonstrated that l-ergothioneine enhanced the level of reduced glutathione and protected cells from the induction of a photoaging-associated mtDNA “common deletion”. In view of our results, l-ergothioneine could be an effective skin care and anti-photoaging ingredient.

  12. Long-Term Performance of Uranium Tailings Disposal Cells - 13340

    International Nuclear Information System (INIS)

    Bostick, Kent; Daniel, Anamary; Pill, Ken; Tachiev, Georgio; Noosai, Nantaporn; Villamizar, Viviana

    2013-01-01

    Recently, there has been interest in the performance and evolution of Uranium Mill Tailings Remedial Action (UMTRA) Project disposal cell covers because some sites are not compliant with groundwater standards. Field observations of UMTRA disposal cells indicate that rock covers tend to become vegetated and that saturated conductivities in the upper portion of radon barriers may increase due to freeze/thaw cycles and biointrusion. This paper describes the results of modeling that addresses whether these potential changes and transient drainage of moisture in the tailings affect overall performance of the disposal cells. A numerical unsaturated/saturated 3-dimensional flow model was used to simulate whether increases in saturated conductivities in radon barriers with rock covers affect the overall performance of the disposal cells using field data from the Shiprock, NM, UMTRA site. A unique modeling approach allowed simulation with daily climatic conditions to determine changes in moisture and moisture flux from the disposal cell. Modeling results indicated that increases in the saturated conductivity at the top of radon barrier do not influence flux from the tailings with time because the tailings behave similar hydraulically to the radon barrier. The presence of a thin layer of low conductivity material anywhere in the cover or tailings restricts flux in the worst case to the saturated conductivity of that material. Where materials are unsaturated at depth within the radon barrier of tailings slimes, conductivities are typically less than 10 -8 centimeters per second. If the low conductivity layer is deep within the disposal cell, its saturated properties are less likely to change with time. The significance of this modeling is that operation and maintenance of the disposal cells can be minimized if they are allowed to progress to a natural condition with some vegetation and soil genesis. Because the covers and underlying tailings have a very low saturated

  13. Long-Term Performance of Uranium Tailings Disposal Cells - 13340

    Energy Technology Data Exchange (ETDEWEB)

    Bostick, Kent; Daniel, Anamary; Pill, Ken [Professional Project Services, Inc., 1100 Bethel Valley Road, Oak Ridge, TN, 37922 (United States); Tachiev, Georgio; Noosai, Nantaporn; Villamizar, Viviana [Florida International University, 10555 W. Flagler St., EC 2100, Miami FL, 33174 (United States)

    2013-07-01

    Recently, there has been interest in the performance and evolution of Uranium Mill Tailings Remedial Action (UMTRA) Project disposal cell covers because some sites are not compliant with groundwater standards. Field observations of UMTRA disposal cells indicate that rock covers tend to become vegetated and that saturated conductivities in the upper portion of radon barriers may increase due to freeze/thaw cycles and biointrusion. This paper describes the results of modeling that addresses whether these potential changes and transient drainage of moisture in the tailings affect overall performance of the disposal cells. A numerical unsaturated/saturated 3-dimensional flow model was used to simulate whether increases in saturated conductivities in radon barriers with rock covers affect the overall performance of the disposal cells using field data from the Shiprock, NM, UMTRA site. A unique modeling approach allowed simulation with daily climatic conditions to determine changes in moisture and moisture flux from the disposal cell. Modeling results indicated that increases in the saturated conductivity at the top of radon barrier do not influence flux from the tailings with time because the tailings behave similar hydraulically to the radon barrier. The presence of a thin layer of low conductivity material anywhere in the cover or tailings restricts flux in the worst case to the saturated conductivity of that material. Where materials are unsaturated at depth within the radon barrier of tailings slimes, conductivities are typically less than 10{sup -8} centimeters per second. If the low conductivity layer is deep within the disposal cell, its saturated properties are less likely to change with time. The significance of this modeling is that operation and maintenance of the disposal cells can be minimized if they are allowed to progress to a natural condition with some vegetation and soil genesis. Because the covers and underlying tailings have a very low saturated

  14. Preliminary performance assessment for the Waste Isolation Pilot Plant, December 1992. Volume 1, Third comparison with 40 CFR 191, Subpart B

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-01

    Before disposing of transuranic radioactive wastes in the Waste Isolation Pilot Plant (WIPP), the United States Department of Energy (DOE) must evaluate compliance with applicable long-term regulations of the United States Environmental Protection Agency (EPA). Sandia National Laboratories is conducting iterative performance assessments of the WIPP for the DOE to provide interim guidance while preparing for final compliance evaluations. This volume contains an overview of WIPP performance assessment and a preliminary comparison with the long-term requirements of the Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes (40 CFR 191, Subpart B).

  15. Preliminary performance evaluation of on-the-fly doppler broadening capability for Monte Carlo simulation in MCS

    International Nuclear Information System (INIS)

    Khassenov, A.; Choi, S.; Lee, H.; Zhang, P.; Zheng, Y.; Lee, D.

    2015-01-01

    This paper examines multipole representation of the cross section and its further Doppler broadening at the resolved resonance region. At the first step, a conversion is performed from nuclear data file resonance parameters to multipoles, which are corresponding poles and residues. The application of multipole representation allows generating the cross section at the target temperature, without pre-generation of 0K cross section libraries. In order to reduce the computational time for cross section generation, window energy concept was implemented and tested. On-the-fly Doppler broadening module based on multipole and windowed multipole representations were implemented into Monte Carlo code, and a pin cell problem was simulated. Simulation time and multiplication factors for different cases were compared with original Monte Carlo simulation results. (author)

  16. Business cycles and the financial performance of fuel cell companies

    International Nuclear Information System (INIS)

    Henriques, I.; Sadorsky, P.

    2005-01-01

    Fuel cells are expected to play a major role in a hydrogen powered world. They will provide power to homes, modes of transportation and appliances. Hydrogen is the most abundant element in nature, but it must be extracted in order to be usable. It can be produced from oil, natural gas and coal or from renewable sources such as biomass, thermal or nuclear reactions. Fuel cells running on hydrogen extracted from non renewable resources have an efficiency of 30 per cent, which is twice as efficient as an internal combustion engine. The greatest barrier to mass commercialization is the cost of making hydrogen-powered auto engines. Also, an infrastructure must be developed to refill hydrogen cars. One solution is to build a hydrogen highway using the existing natural gas grid to produce hydrogen and sell it at existing filling stations. The cost of building 12,000 refueling pumps in urban areas which will provide access to 70 per cent of America's population is estimated at $10 to $15 billion. This paper described the vector autoregression (VAR) model which empirically examines the relationship between financial performance of fuel cell companies and business cycles. It was used to measure how sensitive the financial performance of fuel cell companies are to changes in macroeconomic activity. A four variable VAR model was developed to examine the relationship between stock prices, oil prices and interest rates. It was shown that the stock prices of fuel cell companies are affected by shocks to technology stock prices and oil prices, with the former having a longer lasting impact. These results add to the growing literature that oil price movements are not as important as once thought. 15 refs., 3 tabs., 3 figs

  17. Phenotype of dendritic cells generated in the presence of non-small cell lung cancer antigens - preliminary report.

    Directory of Open Access Journals (Sweden)

    Dariusz Sagan

    2009-01-01

    Full Text Available Therapeutic outcomes of definitively treated non-small-cell lung cancer (NSCLC are unacceptably poor. It has been proposed that the manipulation of dendritic cells (DCs as a "natural" vaccine adjuvant may prove to be a particularly effective way to stimulate antitumor immunity. Presently, there is no standardized methodology for preparing vaccines and many questions concerning the optimal source and type of antigens as well as maturation state and activity of DCs are still unsolved. The study population comprised of ten patients with histologically confirmed NSCLC (mean age: 67.63 +/- 6.15 years. Resected small tumor pieces were placed in tissue culture dishes containing different growth factors in order to obtain pure cancer cells. Seven days after the operation, the PBMC were collected and monocytes were purified by the adherence to culture dishes. Monocytes were cultured in RPMI 1640 medium supplemented with 10% of autologous plasma in the presence of rhIL-4 and rhGM-CSF to generate immature autologous (DCs. TNF-alpha with or without tumor cells' lysate were added to maturation of DCs. After 7 days of culture, DCs were harvested and the expression of CD1a, CD83, CD80, CD86 and HLA-DR antigens were analyzed by flow cytometry. We discovered higher (p=0.07 percentage of semimature DCs in tumor cell lysate culture in comparison with TNF-alpha culture (21.22 +/- 16.82% versus 11.27 +/- 11.64%. The expression of co-stimulatory and maturation markers (CD86, CD83 and HLA-DR was higher on DCs from the culture with tumor cell lysate compared with TNF-alpha culture as a control. Specimen of NSCLC's culture prepared in this way could generate differences in DCs phenotype, which may have an influence on the therapeutic and protective antitumor immunity of the vaccine. Our research seems to be the next step in the development of DC-based vaccine. We are going to continue the investigation to start the preparation of a pattern of immunological vaccine

  18. Moderate dose of hydroxyurea in children with sickle cell disease and stroke. Preliminary results

    OpenAIRE

    Machín-García, Sergio; Menéndez-Veitía, Andrea; Scherle-Matamoros, Claudio; Svarch, Eva; González-Otero, Alejandro; Arencibia-Núñez, Alberto; Gutiérrez-Díaz, Adys; Lam-Díaz, Rosa M

    2014-01-01

    Twenty children with sickle cell anemia, two with SC hemoglobinopathy and one with S/â0 thalassemia were treated, with a previous stroke or abnormal ultrasound transcranial Doppler (TCD) flow velocities more than 170 cm/s. The mean follow-up was of 41 ± 19 months. Hydroxyurea (HU) at a dose of 25 mg/kg/day associated with chronic transfusion therapy, was administrated during one year to patients with stroke. Patients with abnormal TCD received only HU at the same dose. There was a significant...

  19. Energy harvesting influences electrochemical performance of microbial fuel cells

    Science.gov (United States)

    Lobo, Fernanda Leite; Wang, Xin; Ren, Zhiyong Jason

    2017-07-01

    Microbial fuel cells (MFCs) can be effective power sources for remote sensing, wastewater treatment and environmental remediation, but their performance needs significant improvement. This study systematically analyzes how active harvesting using electrical circuits increased MFC system outputs as compared to passive resistors not only in the traditional maximal power point (MPP) but also in other desired operating points such as the maximum current point (MCP) and the maximum voltage point (MVP). Results show that active harvesting in MPP increased power output by 81-375% and active harvesting in MCP increased Coulombic efficiency by 207-805% compared with resisters operated at the same points. The cyclic voltammograms revealed redox potential shifts and supported the performance data. The findings demonstrate that active harvesting is a very effective approach to improve MFC performance across different operating points.

  20. Preliminary study for non – invasive optical detection of squamous and basal cell carcinomas

    Directory of Open Access Journals (Sweden)

    Ali Ahmed Mohammed

    2012-11-01

    Full Text Available Abstract Background The early detection of skin cancer may highly increase the chances of its healing. One of the non-invasive methods of such detection based on the Oblique- Incidence Diffuse Reflectance (OIDR measurements of the reflected diode laser light from the skin. In this research we designed and implemented the OIDR reflectometry measuring system with a 650 nm diode laser source to aid physicians in diagnosing both squamous cell carcinomas (SCC and basal cell carcinomas(BCC. Method The laser is delivered obliquely to the skin surface by an optical fiber fitted through a tube holder of CCD camera. The diffused reflected laser light from the skin is captured by the CCD camera and sent to a computer, which is supplied by a specially prepared Matlab program to analyze these images in order to decide in a time whether the lesion is malignant or benign. Fifty cases were diagnosed under supervision of the consultant section of The Governmental Specialized Marjan Teaching Hospital – MOH – Iraq. Result The fifty diagnosed cases by this technique, the results were 90% accurate. Conclusion The method of laser oblique-incidence diffuse reflectance (OIDR combined with using the developed algorithms that have high classification rates may prove useful in the clinic as the process is fast, noninvasive and accurate.

  1. Determinants of academic performance in children with sickle cell anaemia.

    Science.gov (United States)

    Ezenwosu, Osita U; Emodi, Ifeoma J; Ikefuna, Anthony N; Chukwu, Barth F; Osuorah, Chidiebere D

    2013-11-19

    Some factors are known to influence the academic performance of children with Sickle Cell Anaemia (SCA). Information on their effects in these children is limited in Nigeria. The factors which influence academic performance of children with SCA in Enugu, Nigeria are determined in this study. Consecutive children with SCA aged 5-11 years were recruited at the weekly sickle cell clinic of the University of Nigeria Teaching Hospital (UNTH) Enugu, Nigeria. Their age- and sex- matched normal classmates were recruited as controls. The total number of days of school absence for 2009/2010 academic session was obtained for each pair of pupils from the class attendance register. Academic performance was assessed using the average of the overall scores in the three term examinations of same session. Intelligence ability was determined with Draw-A-Person Quotient (DAPQ) using the Draw-A-Person Test while socio-economic status was determined using the occupational status and educational attainment of each parent. Academic performance of children with SCA showed statistically significant association with their socio-economic status (χ2 = 9.626, p = 0.047), and significant correlation with DAPQ (r = 0.394, p = 0.000) and age (r = -0.412, p = 0.000). However, no significant relationship existed between academic performance and school absence in children with SCA (r = -0.080, p = 0.453). Academic performance of children with SCA is influenced by their intelligence ability, age and socio-economic status but not negatively affected by their increased school absenteeism.

  2. Break-in and Performance Issues on a single cell PBI-based PEM Fuel Cell

    DEFF Research Database (Denmark)

    Kær, Søren Knudsen; Jespersen, Jesper Lebæk

    of the fuel cell, even though break-in of a fuel cell implemented in a commercial application would most likely not be feasible. In the present work a commercially available PBI-based high temperature MEA is subject to a break-in procedure, as specified by the manufacturer. The cell was operated at 160 °C...... during the break-in procedure at a current density of 0.2 A/cm2. The performance of the cell was measured over the 100 hour break-in period and a polarization curve was recorded after completion of break-in. The performance change was minimal during the break-in cycle. However, in the first hour of op......-eration a significant performance decrease of 30 mV was observed. Hereafter a performance in-crease started and the overall performance change during the break-in procedure was a voltage in-crease of 35 mV corresponding to a rate of 240 μV/hr. The performance increase was however fast-est in the first 50 hours...

  3. Performance evaluation of an air-breathing high-temperature proton exchange membrane fuel cell

    International Nuclear Information System (INIS)

    Wu, Qixing; Li, Haiyang; Yuan, Wenxiang; Luo, Zhongkuan; Wang, Fang; Sun, Hongyuan; Zhao, Xuxin; Fu, Huide

    2015-01-01

    Highlights: • An air-breathing HT-PEMFC was designed and evaluated experimentally. • The peak power density of the air-breathing HT-PEMFC was 220.5 mW cm"−"2 at 200 °C. • Break-in behavior and effects of temperature and anodic stoichiometry were studied. • The effect of cell orientations on the performance was investigated. • The degradation rate of the air-breathing HT-PEMFC was around 58.32 μV h"−"1. - Abstract: The air-breathing proton exchange membrane fuel cell (PEMFC) is of great interest in mobile power sources because of its simple system design and low parasitic power consumption. Different from previous low-temperature air-breathing PEMFCs, a high-temperature PEMFC with a phosphoric acid doped polybenzimidazole (PBI) membrane as the polymer electrolyte is designed and investigated under air-breathing conditions. The preliminary results show that a peak power density of 220.5 mW cm"−"2 at 200 °C can be achieved without employing any water managements, which is comparable to those with conventional Nafion® membranes operated at low temperatures. In addition, it is found that with the present cell design, the limiting current density arising from the oxygen transfer limitation is around 700 mA cm"−"2 even at 200 °C. The short-term durability test at 200 mA cm"−"2 and 180 °C reveals that all the cells exhibit a gradual decrease in the voltage along with a rise in the internal resistance. The degradation rate of continuous operation is around 58.32 μV h"−"1, which is much smaller than those of start/stop cycling operations.

  4. Glucose-based Biofuel Cells: Nanotechnology as a Vital Science in Biofuel Cells Performance

    OpenAIRE

    Hamideh Aghahosseini; Ali Ramazani; Pegah Azimzadeh Asiabi; Farideh Gouranlou; Fahimeh Hosseini; Aram Rezaei; Bong-Ki Min; Sang Woo Joo

    2016-01-01

    Nanotechnology has opened up new opportunities for the design of nanoscale electronic devices suitable for developing high-performance biofuel cells. Glucose-based biofuel cells as green energy sources can be a powerful tool in the service of small-scale power source technology as it provides a latent potential to supply power for various implantable medical electronic devices. By using physiologically produced glucose as a fuel, the living battery can recharge for continuous production of el...

  5. Performance analysis of a stationary fuel cell thermoelectric cogeneration system

    Energy Technology Data Exchange (ETDEWEB)

    Kuo, J.K.; Hwang, J.J.; Lin, C.H. [Department of Greenergy, National University of Tainan, Tainan, 70005 (China)

    2012-12-15

    The main purpose of our study was to use an experimental method and system dynamic simulation technology to examine a proton exchange membrane fuel cell thermoelectric cogeneration system that provides both high-quality electric power and heated water. In the second part of our study, we experimentally verified the development of key components of the fuel cell and conducted a comprehensive analysis of the subsystems, including the fuel cell module, hydrogen supply subsystem, air supply subsystem, humidifier subsystem, and heat recovery subsystem. Finally, we integrated all of the subsystems into a PEM fuel cell thermoelectric cogeneration system and performed efficiency tests and analysis of power generation, heat recovery, and thermoelectric cogeneration. After comparing this system's efficiency results using simulation and experimentation, we determined that the accuracy of the simulation values when compared to the experimental values was >95%, showing that this system's simulation nearly approached the efficiency of the actual experiment, including more than 53% for power generation efficiency, more than 39% for heat recovery efficiency, and more than 93% for thermoelectric cogeneration combined efficiency. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Purification, crystallization and preliminary crystallographic analysis of the SH2 domain of IL-2-inducible T-cell kinase.

    Science.gov (United States)

    Joseph, Raji E; Ginder, Nathaniel D; Hoy, Julie A; Nix, Jay C; Honzatko, Richard B; Andreotti, Amy H

    2011-02-01

    Proline is a unique amino acid owing to the relatively small energy difference between the cis and trans conformations of its peptide bond. The X-Pro imide bond readily undergoes cis-trans isomerization in the context of short peptides as well as some proteins. However, the direct detection of cis-trans proline isomerization in folded proteins is technically challenging. NMR spectroscopy is well suited to the direct detection of proline isomerization in folded proteins. It is less clear how well X-ray crystallography can reveal this conformational exchange event in folded proteins. Conformational heterogeneity owing to cis-trans proline isomerization in the Src homology 2 (SH2) domain of the IL-2-inducible T-cell kinase (ITK) has been extensively characterized by NMR. Using the ITK SH2 domain as a test system, an attempt was made to determine whether proline isomerization could be detected in a crystal structure of the ITK SH2 domain. As a first step towards this goal, the purification, crystallization and preliminary characterization of the ITK SH2 domain are described.

  7. Conceptual development of a building-integrated photovoltaic–radiative cooling system and preliminary performance analysis in Eastern China

    International Nuclear Information System (INIS)

    Zhao, Bin; Hu, Mingke; Ao, Xianze; Pei, Gang

    2017-01-01

    Highlights: •A specific spectral characteristic for both PV and RC was proposed. •The PV/RC hybrid system based on spectral characteristic is original. •A thermal model of the system was established and the performance was analyzed. •The performance comparison with the conventional PV system was conducted. •The system shows considerable performance for both PV and RC. -- Abstract: Building-integrated photovoltaic/thermal (BIPV/T) technology has been receiving considerable research attention because of its ability to generate electricity and thermal energy simultaneously. However, space cooling is crucial for buildings in hot regions where space heating is of little use. This study proposed a building-integrated photovoltaic–radiative cooling system (BIPV–RC) that can generate electricity via photovoltaic (PV) conversion during daytime and generate cooling energy via radiative cooling (RC) during nighttime to satisfy the demand in such areas. The selective plate, which is the main component of the BIPV–RC system, exhibits high spectral absorptivity (emissivity) in the PV conversion band of crystalline silicon solar cells and in the atmospheric window band (i.e., 0.3–1.1 μm and 8–13 μm), as well as low spectral absorptivity (emissivity) in other bands. A quasi-steady-state mathematical model was built, and its performance under realistic ambient conditions was analyzed. The electrical efficiencies of the BIPV–RC and conventional BIPV systems were then compared under different solar radiations. Comparison results show that the annual electricity production and cooling energy gain of the BIPV–RC system in Hefei reached 156.74 kW h m −2 (equivalent to 564.26 MJ m −2 ) and 579.91 MJ m −2 , respectively. The total electricity production and cooling energy gain of this system are 96.96% higher than those of the BIPV system. Parametric studies show that the precipitable water vapor amount has remarkable effects on the nocturnal RC performance

  8. Effect of Perovskite Film Preparation on Performance of Solar Cells

    Directory of Open Access Journals (Sweden)

    Yaxian Pei

    2016-01-01

    Full Text Available For the perovskite solar cells (PSCs, the performance of the PSCs has become the focus of the research by improving the crystallization and morphology of the perovskite absorption layer. In this thesis, based on the structure of mesoporous perovskite solar cells (MPSCs, we designed the experiments to improve the photovoltaic performance of the PSCs by improved processing technique, which mainly includes the following two aspects. Before spin-coating PbI2 solution, we control the substrate temperature to modify the crystal quality and morphology of perovskite films. On the other hand, before annealing, we keep PbI2 films for the different drying time at room temperature to optimize films morphology. In our trials, it was found that the substrate temperature is more important in determining the photovoltaic performance than drying time. These results indicate that the crystallization and morphology of perovskite films affect the absorption intensity and obviously influence the short circuit current density of MPSCs. Utilizing films prepared by mentioning two methods, MPSCs with maximum power conversion efficiency of over 4% were fabricated for the active area of 0.5 × 0.5 cm2.

  9. Microstructured Electrolyte Membranes to Improve Fuel Cell Performance

    Science.gov (United States)

    Wei, Xue

    Fuel cells, with the advantages of high efficiency, low greenhouse gas emission, and long lifetime are a promising technology for both portable power and stationary power sources. The development of efficient electrolyte membranes with high ionic conductivity, good mechanical durability and dense structure at low cost remains a challenge to the commercialization of fuel cells. This thesis focuses on exploring novel composite polymer membranes and ceramic electrolytes with the microstructure engineered to improve performance in direct methanol fuel cells (DMFCs) and solid oxide fuel cells (SOFCs), respectively. Polymer/particle composite membranes hold promise to meet the demands of DMFCs at lower cost. The structure of composite membranes was controlled by aligning proton conducting particles across the membrane thickness under an applied electric field. The field-induced structural changes caused the membranes to display an enhanced water uptake, proton conductivity, and methanol permeability in comparison to membranes prepared without an applied field. Although both methanol permeability and proton conductivity are enhanced by the applied field, the permeability increase is relatively lower than the proton conductivity improvement, which results in enhanced proton/methanol selectivity and improved DMFC performance. Apatite ceramics are a new class of fast ion conductors being studied as alternative SOFC electrolytes in the intermediate temperature range. An electrochemical/hydrothermal deposition method was developed to grow fully dense apatite membranes containing well-developed crystals with c-axis alignment to promote ion conductivity. Hydroxyapatite seed crystals were first deposited onto a metal substrate electrochemically. Subsequent ion substitution during the hydrothermal growth process promoted the formation of dense, fully crystalline films with microstructure optimal for ion transport. The deposition parameters were systematically investigated, such as

  10. Social skills and executive function among youth with sickle cell disease: a preliminary investigation.

    Science.gov (United States)

    Hensler, Molly; Wolfe, Kelly; Lebensburger, Jeffrey; Nieman, Jilian; Barnes, Margaux; Nolan, William; King, Allison; Madan-Swain, Avi

    2014-06-01

    To explore the relationship between executive function (EF) and social skills in youth with sickle cell disease (SCD).   20 youth with SCD completed objective tests of EF (Tasks of Executive Control; Animal Sorting subtest from the Developmental Neuropsychological Assessment-Second Edition), an IQ screener, and paper-and-pencil measures of social skills (Social Skills Improvement System [SSIS]). Primary caregivers completed paper-and-pencil measures of EF (Behavior Rating Inventory of Executive Function) and social skills (SSIS).   EF scores from the Behavior Rating Inventory of Executive Function related to parent- and child-reported social skills such that EF deficits correlated with poorer overall and domain-specific social skills. Similarly, EF scores from the Animal Sorting test related to child-reported social skills. Worse parent-reported EF predicted worse parent-reported social skills above the variance accounted for by IQ.   EF is related to social skills and may be necessary for successful social interaction among youth with SCD. These results provide rationale and guidance for future larger-scale investigations of EF and social skills among children with SCD. © The Author 2014. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. STEREOLOGICAL ESTIMATION OF ITO CELLS FROM RAT LIVER USING THE OPTICAL FRACTIONATOR - A PRELIMINARY REPORT

    Directory of Open Access Journals (Sweden)

    Ricardo Marcos

    2011-05-01

    Full Text Available In the last two decades, much light has been shed on hepatic fibrosis, and the activation / proliferation of Ito cells (IC emerged to play a central role. Therefore, it is essential to have solid quantitative data in nonpathological statuses; yet, this data is scarce and confined to "number per area" or semiquantitative information. Moreover, the supposed heterogeneous distribution of IC in the hepatic lobule was never analysed with design-based (unbiased stereology. In the present study, the total number (N of IC in rat liver was estimated for the first time, by combining immunocytochemistry with the optical fractionator. Quantification was extended to the hepatocytes, to disclose the IC index, an often-used ratio in hepatology. Systematic uniform random liver sections were obtained from male Wistar rats (n = 3, and immunostained against glial fibrillary acidic protein (GFAP, a known specific marker for hepatic IC. For the first time, these were marked against GFAP in thick (30 μm paraffin sections. The estimated N of IC was 224E06; with a coefficient of error of 0.04 or 0.06, depending on the particular equation used (based on the so-called "quadratic approximation". The IC index was 91 IC/1000 hepatocytes. Concerning the lobular heterogeneity, it was proved the liver harbours a larger total number of periportal IC and hepatocytes.

  12. Preliminary study on biological dosimetry using alkaline single cell gel electrophoresis of human peripheral lymphocytes

    International Nuclear Information System (INIS)

    Liu Qingjie; Lu Xue; Feng Jiangbing; Chen Deqing; Chen Xiaosui

    2006-01-01

    Objective: To explore the feasibility of alkaline single cell gel electrophoresis (SCGE) in biological dosimetry of ionizing radiation. Methods: Normal peripheral blood samples from two healthy males were exposed to different doses coblat-60 gamma-rays, ranged from 0 to 5 Gy, and the tail length (TL) and Oliver tail moment (TM) of the lymphocytes were analyzed with SCGE. The dose-effect curves of TL and TM were fitted respectively. The TL and TM of lymphocytes for eight radiation workers were analyzed with SCGE, cumulative doses were estimated using the fitted TL and TM equations, and then compared with the recorded monitoring doses. Results: The TLs or TMs of normal human lymphocytes were increased with the irradiation doses, and its relationship can be fitted with a linear-quadratic equations: Y=13.59 + 20.87X - 2.27 X 2 for TL, and Y = 8.50 + 15.04X - 1.43X 2 for TM, respectively (Y denotes TL or TM value, X is radiation dose). The doses estimated with TM equation were closer to the recorded monitoring doses than that with TL equation. Conclusions: The TM in lymphocytes analyzed with SCGE is a promising radiation biological dosimeter. (authors)

  13. Suns-VOC characteristics of high performance kesterite solar cells

    Science.gov (United States)

    Gunawan, Oki; Gokmen, Tayfun; Mitzi, David B.

    2014-08-01

    Low open circuit voltage (VOC) has been recognized as the number one problem in the current generation of Cu2ZnSn(Se,S)4 (CZTSSe) solar cells. We report high light intensity and low temperature Suns-VOC measurement in high performance CZTSSe devices. The Suns-VOC curves exhibit bending at high light intensity, which points to several prospective VOC limiting mechanisms that could impact the VOC, even at 1 sun for lower performing samples. These VOC limiting mechanisms include low bulk conductivity (because of low hole density or low mobility), bulk or interface defects, including tail states, and a non-ohmic back contact for low carrier density CZTSSe. The non-ohmic back contact problem can be detected by Suns-VOC measurements with different monochromatic illuminations. These limiting factors may also contribute to an artificially lower JSC-VOC diode ideality factor.

  14. Preliminary evaluation of a microbial fuel cell treating artificial dialysis wastewater using graphene oxide

    Science.gov (United States)

    Goto, Yuko; Yoshida, Naoko

    2016-02-01

    Artificial dialysis wastewater (ADWW) generally contains 800-2,200 mg L-1 of organic matter. Prior to its discharge to the sewage system, ADWW must be treated in order to reduce organic matter to less than 600 mg L-1. This study assesses the applicability of a microbial fuel cell (MFC) to the reduction of organic matter in ADWW as an alternative pre-treatment system to aeration. In the MFC, conductive floccular aggregates microbially produced from graphene oxide (GO-flocs) were applied as an anode material in the MFC. The GO-flocs were obtained by anaerobic incubation of graphene oxide (GO) with microorganisms in ADWW at 28 °C for a minimum of 10 days. During incubation, GO in the mixture was transformed into black conductive floccular aggregates having 0.12 mS cm-1, suggesting the microbial reduction of GO to the reduced form. The produced GO-flocs were then used as the anode material in a cylindrical MFC, which was filled with ADWW and covered with a floating, platinum (Pt)-coated carbon cathode. The MFC was polarized via an external resistance of 10 Ω and applied for 120 days by replacing half of the supernatant of the MFC with fresh ADWW, every 6-9 days. As a result, the MFC achieved a 128 mg L-1 d-1 chemical oxygen demand (CODCr) removal rate. For example, the MFC contained 1,500 mg-CODCr L-1 just after replacement, with this concentration being reduced to 1,000 mg-CODCr L-1 after 6-9 days of incubation. At the same time, the MFC showed an average power density of 28 mW m-2 and a maximum power density of 291 mW m-2. These results suggest that a MFC packed with GO-flocs can be used as an alternative biotreatment system, replacing the energy-intensive aeration process.

  15. Preliminary results of three-dimensional conformal radiotherapy for non-small cell lung cancer

    International Nuclear Information System (INIS)

    Wang Yingjie; Wang Luhua; Wang Xin; Feng Qinfu; Zhang Hongxing; Xiao Zefen; Yin Weibo

    2005-01-01

    Objective: To evaluate the therapeutic effects and complications of three-dimensional conformal radiotherapy (3DCRT) for non-small cell lung cancer (NSCLC). Methods: Between March 1999 and September 2003, 91 NSCLC patients treated with 3DCRT were reviewed at the Cancer Hospital, Chinese Academy of Medical Sciences. This patient cohort consisted of 73 men and 18 women. The median age was 66 years. Radio-therapy was delivered at 2 Gy fraction, 5 fractions per week. The median total dose was 60 Gy. Results: With a median follow-up time of 17 months, the response rate after 3DCRT was 57.1%, with complete remission 11.0% (10/91) and partial remission 46.2%(42/91). The median survival time (MST) was 16 months, with 1- and 2- year overall survivals (OS) of 67.0% and 32.6%, 1- and 2-year local progression free survivals (LPFS) of 82.6% and 53.0%, respectively. The independent adverse prognostic factors by univariate analysis and multivariate analysis was weight loss ≥5%. Grade 2 acute radiation pneumonitis was observed in 2 patients and grade 3 in 4 patients. Late lung injury developed in 1 patient with grade 2, 1 patient with grade 3, respectively. Acute radiation esophagitis was observed in 8 patients with grade 2. Acute grade 2 hematologic toxicity developed in 5 patients. Conclusions: 3DCRT was feasible in the treatment of NSCLC with good immediate tumor response and acceptable normal tissue complication. The total dose may potentially be increased. (authors)

  16. Standard Test Method for Electrical Performance of Photovoltaic Cells Using Reference Cells Under Simulated Sunlight

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This test method covers the determination of the electrical performance of a photovoltaic cell under simulated sunlight by means of a calibrated reference cell procedure. 1.2 Electrical performance measurements are reported with respect to a select set of standard reporting conditions (SRC) (see Table 1) or to user-specified conditions. 1.2.1 The SRC or user-specified conditions include the cell temperature, the total irradiance, and the reference spectral irradiance distribution. 1.3 This test method is applicable only to photovoltaic cells with a linear response over the range of interest. 1.4 The cell parameters determined by this test method apply only at the time of test, and imply no past or future performance level. 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this s...

  17. The Impact of 2008 Global Financial Crisis on the Performance of Selected Indonesian Stocks: A Preliminary Study

    Directory of Open Access Journals (Sweden)

    Edwin Suparman

    2014-08-01

    Full Text Available This research is a preliminary study that analyzes the impact of the US financial markets on Indonesian financial markets during the 2008 global financial crisis. It specifically investigates the occurrence of contagion effect in the Indonesian IHSG index and selected LQ45 stocks with the US S&P500 index by the measurement of correlation using simple correlation, EWMA, OGARCH, and DCC GARCH. It also attempts to discuss on the decoupling of Indonesian market and provide recommendations on dealing with future similar events.

  18. Monitoring the Microgravity Environment Quality On-board the International Space Station Using Soft Computing Techniques. Part 2; Preliminary System Performance Results

    Science.gov (United States)

    Jules, Kenol; Lin, Paul P.; Weiss, Daniel S.

    2002-01-01

    This paper presents the preliminary performance results of the artificial intelligence monitoring system in full operational mode using near real time acceleration data downlinked from the International Space Station. Preliminary microgravity environment characterization analysis result for the International Space Station (Increment-2), using the monitoring system is presented. Also, comparison between the system predicted performance based on ground test data for the US laboratory "Destiny" module and actual on-orbit performance, using measured acceleration data from the U.S. laboratory module of the International Space Station is presented. Finally, preliminary on-orbit disturbance magnitude levels are presented for the Experiment of Physics of Colloids in Space, which are compared with on ground test data. The ground test data for the Experiment of Physics of Colloids in Space were acquired from the Microgravity Emission Laboratory, located at the NASA Glenn Research Center, Cleveland, Ohio. The artificial intelligence was developed by the NASA Glenn Principal Investigator Microgravity Services Project to help the principal investigator teams identify the primary vibratory disturbance sources that are active, at any moment of time, on-board the International Space Station, which might impact the microgravity environment their experiments are exposed to. From the Principal Investigator Microgravity Services' web site, the principal investigator teams can monitor via a dynamic graphical display, implemented in Java, in near real time, which event(s) is/are on, such as crew activities, pumps, fans, centrifuges, compressor, crew exercise, structural modes, etc., and decide whether or not to run their experiments, whenever that is an option, based on the acceleration magnitude and frequency sensitivity associated with that experiment. This monitoring system detects primarily the vibratory disturbance sources. The system has built-in capability to detect both known

  19. High-performance polymer photovoltaic cells and photodetectors

    Science.gov (United States)

    Yu, Gang; Srdanov, Gordana; Wang, Hailiang; Cao, Yong; Heeger, Alan J.

    2001-02-01

    Polymer photovoltaic cells and photodetectors have passed their infancy and become mature technologies. The energy conversion efficiency of polymer photovoltaic cells have been improved to over 4.1% (500 nm, 10 mW/cm2). Such high efficiency polymer photovoltaic cells are promising for many applications including e-papers, e-books and smart- windows. The development of polymer photodetectors is even faster. The performance parameters have been improved to the level meeting all specifications for practical applications. The polymer photodetectors are of high photosensitivity (approximately 0.2 - 0.3 A/Watt in visible and UV), low dark current (0.1 - 1 nA/cm2), large dynamic range (> 8 orders of magnitude), linear intensity dependence, low noise level and fast response time (to nanosecond time domain). These devices show long shelf and operation lives. The advantages of low manufacturing cost, large detection area, and easy hybridization and integration with other electronic or optical components make the polymer photodetectors promising for a variety of applications including chemical/biomedical analysis, full-color digital image sensing and high energy radiation detection.

  20. CDTE alloys and their application for increasing solar cell performance

    Science.gov (United States)

    Swanson, Drew E.

    Cadmium Telluride (CdTe) thin film solar is the largest manufactured solar cell technology in the United States and is responsible for one of the lowest costs of utility scale solar electricity at a purchase agreement of $0.0387/kWh. However, this cost could be further reduced by increasing the cell efficiency. To bridge the gap between the high efficiency technology and low cost manufacturing, a research and development tool and process was built and tested. This fully automated single vacuum PV manufacturing tool utilizes multiple inline close space sublimation (CSS) sources with automated substrate control. This maintains the proven scalability of the CSS technology and CSS source design but with the added versatility of independent substrate motion. This combination of a scalable deposition technology with increased cell fabrication flexibility has allowed for high efficiency cells to be manufactured and studied. The record efficiency of CdTe solar cells is lower than fundamental limitations due to a significant deficit in voltage. It has been modeled that there are two potential methods of decreasing this voltage deficiency. The first method is the incorporation of a high band gap film at the back contact to induce a conduction-band barrier that can reduce recombination by reflecting electrons from the back surface. The addition of a Cd1-x MgxTe (CMT) layer at the back of a CdTe solar cell should induce this desired offset and reflect both photoelectrons and forward-current electrons away from the rear surface. Higher collection of photoelectrons will increase the cells current and the reduction of forward current will increase the cells voltage. To have the optimal effect, CdTe must have reasonable carrier lifetimes and be fully depleted. To achieve this experimentally, CdTe layers have been grown sufficiently thin to help produce a fully depleted cell. A variety of measurements including performance curves, transmission electron microscopy, x

  1. Understanding the Photovoltaic Performance of Perovskite-Spirobifluorene Solar Cells.

    Science.gov (United States)

    Song, Zhen; Liu, Jiang; Wang, Gang; Zuo, Wentao; Liao, Cheng; Mei, Jun

    2017-11-03

    Lead halide perovskite solar cells with remarkable power conversion efficiency have attracted much attention in recent years. However, there still exist many problems with their use that are not completely understood, and further studies are needed. Herein, the hole-transport layer dependence of the photovoltaic performance of perovskite solar cells is investigated in detail. It is found that devices freshly prepared using pristine 2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-OMeTAD) and Li-doped spiro-OMeTAD as hole-transport layers exhibit S-shaped current density-voltage curves with poor fill factors. The devices show progressively improved fill factors and efficiencies upon exposure to air, which is attributed to air-induced conductivity improvement in the spiro-OMeTAD layer. After introducing a cobalt salt dopant (FK209) into the spiro-OMeTAD layer, the corresponding devices show remarkable performance without the need of air exposure. These results confirm that the dopant not only increases the conductivity of spiro-OMeTAD layer, but also tunes the surface potential, which helps to improve charge transport and reduce the recombination loss. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Performance of fuel cell for energy supply of passive house

    Energy Technology Data Exchange (ETDEWEB)

    Badea, G.; Felseghi, R. A., E-mail: Raluca.FELSEGHI@insta.utcluj.ro; Mureşan, D.; Naghiu, G. [Technical University of Cluj-Napoca, Building Services Engineering Department, Bd. December 21, no. 128-130, 400600, Cluj-Napoca (Romania); Răboacă, S. M. [National R& D Institute for Cryogenic and Isotopic Technologies, str. Uzinei, no. 4, Rm. Vălcea, 240050 (Romania); Aşchilean, I. [SC ACI Cluj SA, Avenue Dorobanţilor, no. 70, 400609, Cluj-Napoca (Romania)

    2015-12-23

    Hydrogen technology and passive house represent two concepts with a remarkable role for the efficiency and decarbonisation of energy systems in the residential buildings area. Through design and functionality, the passive house can make maximum use of all available energy resources. One of the solutions to supply energy of these types of buildings is the fuel cell, using this technology integrated into a system for generating electricity from renewable primary sources, which take the function of backup power (energy reserve) to cover peak load and meteorological intermittents. In this paper is presented the results of the case study that provide an analysis of the energy, environmental and financial performances regarding energy supply of passive house by power generation systems with fuel cell fed with electrolytic hydrogen produced by harnessing renewable energy sources available. Hybrid systems have been configured and operate in various conditions of use for five differentiated locations according to the main areas of solar irradiation from the Romanian map. Global performance of hybrid systems is directly influenced by the availability of renewable primary energy sources - particular geo-climatic characteristics of the building emplacement.

  3. Design and performance of U7B beamline and X-ray diffraction and scattering station at NSRL and its preliminary experiments in protein crystallography

    International Nuclear Information System (INIS)

    Pan Guoqiang; Xu, Chaoyin; Fan Rong; Gao Chen; Lou Xiaohua; Teng Maikun; Huang Qingqiu; Niu Liwen

    2005-01-01

    This publication describes the design and performance of the U7B beamline and X-ray diffraction and diffuse scattering station at National Synchrotron Radiation Laboratory (NSRL). The beamline optics comprise a Pt-coated toroidal focusing mirror and a double-crystal Si(1 1 1) monochromator. A preliminary experiment of diffraction data collection and processing was carried out using a commercial imaging plate detector system (Mar345). The data collected from one single crystal of acutohaemolysin, a Lys49-type PLA2 from Agkistrodon acutus venom, are of high quality

  4. How the relative permittivity of solar cell materials influences solar cell performance

    DEFF Research Database (Denmark)

    Crovetto, Andrea; Huss-Hansen, Mathias K.; Hansen, Ole

    2017-01-01

    of the materials permittivity on the physics and performance of the solar cell by means of numerical simulation supported by analytical relations. We demonstrate that, depending on the specific solar cell configuration and materials properties, there are scenarios where the relative permittivity has a major......The relative permittivity of the materials constituting heterojunction solar cells is usually not considered as a design parameter when searching for novel combinations of heterojunction materials. In this work, we investigate the validity of such an approach. Specifically, we show the effect...... the heterojunction partner has a high permittivity, solar cells are consistently more robust against several non-idealities that are especially likely to occur in early-stage development, when the device is not yet optimized....

  5. Preliminary parametric performance assessment of potential final waste forms for alpha low-level waste at the Idaho National Engineering Laboratory. Revision 1

    International Nuclear Information System (INIS)

    Smith, T.H.; Sussman, M.E.; Myers, J.; Djordjevic, S.M.; DeBiase, T.A.; Goodrich, M.T.; DeWitt, D.

    1995-08-01

    This report presents a preliminary parametric performance assessment (PA) of potential waste disposal systems for alpha-contaminated, mixed, low-level waste (ALLW) currently stored at the Transuranic Storage Area of INEL. The ALLW, which contains from 10 to 100 nCi/g of transuranic (TRU) radionuclides, is awaiting treatment and disposal. The purpose of this study was to examine the effects of several parameters on the radiological-confinement performance of potential disposal systems for the ALLW. The principal emphasis was on the performance of final waste forms (FWFs). Three categories of FWF (cement, glass, and ceramic) were addressed by evaluating the performance of two limiting FWFs for each category. Performance at five conceptual disposal sites was evaluated to illustrate the effects of site characteristics on the performance of the total disposal system. Other parameters investigated for effects on receptor dose included inventory assumptions, TRU radionuclide concentration, FWF fracture, disposal depth, water infiltration rates, subsurface-transport modeling assumptions, receptor well location, intrusion scenario assumptions, and the absence of waste immobilization. These and other factors were varied singly and in some combinations. The results indicate that compliance of the treated and disposed ALLW with the performance objectives depends on the assumptions made, as well as on the FWF and the disposal site. Some combinations result in compliance, while others do not. The implications of these results for decision making relative to treatment and disposal of the INEL ALLW are discussed. The report compares the degree of conservatism in this preliminary parametric PA against that in four other PAs and one risk assessment. All of the assessments addressed the same disposal site, but different wastes. The report also presents a qualitative evaluation of the uncertainties in the PA and makes recommendations for further study

  6. Clinical pharmacokinetics, safety, and preliminary efficacy evaluation of icotinib in patients with advanced non-small cell lung cancer.

    Science.gov (United States)

    Liu, Dongyang; Zhang, Li; Wu, Yiwen; Jiang, Ji; Tan, Fenlai; Wang, Yingxiang; Liu, Yong; Hu, Pei

    2015-09-01

    To receive pharmacokinetics, safety, and anti-tumor activity of icotinib, a novel epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor (TKI), in patients with advanced non-small-cell lung cancer (NSCLC). Patients (n=40) with advanced NSCLC were enrolled to receive escalating doses of icotinib, which was administrated on Day 1 followed by 28-day continuous dosing starting from Day 4. Four dosing regimens, 100mg b.i.d., 150 mg b.i.d., 125 mg t.i.d., and 200mg b.i.d. were studied. Pharmacokinetics (PK), safety, and efficacy of icotinib were evaluated. Icotinib was well tolerated in Chinese patients with refractory NSCLC. No toxicity with >3 grades were reported in more than 2 patients under any dose levels. One complete response (3%) and 9 partial responses (23%) were received. Total disease control rate could reach at 73% and median progress-free survival (range) was 154 (17-462) days. PK exposure of icotinib increased with increase of dose in NSCLC patients. Food was suggested to increase PK exposure by ∼30%. Mean t1/2β was within 5.31-8.07 h. No major metabolite (>10% plasma exposure of icotinib) was found in NSCLC patients. Icotinib with up to 400 mg/day exhibited good tolerance and preliminary antitumor activity in Chinese NSCLC patients. Pharmacokinetics of icotinib and 5 major metabolites were fully investigated in NSCLC patients. Optimized biologic dose (OBD) was finally recommended to be 125 mg t.i.d. for the later clinical study. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  7. Brain morphometric analysis predicts decline of intelligence quotient in children with sickle cell disease: A preliminary study.

    Science.gov (United States)

    Chen, Rong; Krejza, Jaroslaw; Arkuszewski, Michal; Zimmerman, Robert A; Herskovits, Edward H; Melhem, Elias R

    2017-03-01

    For children with sickle cell disease (SCD) and at low risk category of stroke, we aim to build a predictive model to differentiate those with decline of intelligence-quotient (IQ) from counterparts without decline, based on structural magnetic-resonance (MR) imaging volumetric analysis. This preliminary prospective cohort study included 25 children with SCD, homozygous for hemoglobin S, with no history of stroke and transcranial Doppler mean velocities below 170cm/s at baseline. We administered the Kaufman Brief Intelligence Test (K-BIT) to each child at yearly intervals for 2-4 years. Each child underwent MR examination within 30 days of the baseline K-BIT evaluation date. We calculated K-BIT change rates, and used rate of change in K-BIT to classify children into two groups: a decline group and a non-decline group. We then generated predictive models to predict K-BIT decline/non-decline based on regional gray-matter (GM) volumes computed from structural MR images. We identified six structures (the left median cingulate gyrus, the right middle occipital gyrus, the left inferior occipital gyrus, the right fusiform gyrus, the right middle temporal gyrus, the right inferior temporal gyrus) that, when assessed for volume at baseline, are jointly predictive of whether a child would suffer subsequent K-BIT decline. Based on these six regional GM volumes and the baseline K-BIT, we built a prognostic model using the K * algorithm. The accuracy, sensitivity and specificity were 0.84, 0.78 and 0.86, respectively. GM volumetric analysis predicts subsequent IQ decline for children with SCD. Copyright © 2017 Medical University of Bialystok. Published by Elsevier B.V. All rights reserved.

  8. Performance of the ACWA Pilot Immobilized Cell Bioreactor in Degradation of HD and Tetrytol Payloads of the M60 Chemical Round

    National Research Council Canada - National Science Library

    Guelta, Mark A; Chester, Nancy A; Kurnas, Carl W; Haley, Mark V; Lupton, F. S; Koch, Mark

    2002-01-01

    .... Neutralization followed by biodegradation was one technology identified as having potential. Guelta and DeFrank conducted preliminary laboratory studies using 1-liter Immobilized Cell Bioreactors (ICB...

  9. Understanding organic photovoltaic cells: Electrode, nanostructure, reliability, and performance

    Science.gov (United States)

    Kim, Myung-Su

    My Ph.D. research has focused on alternative renewable energy using organic semiconductors. During my study, first, I have established reliable characterization methods of organic photovoltaic devices. More specifically, less than 5% variation of power conversion efficiency of fabricated organic blend photovoltaic cells (OBPC) was achieved after optimization. The reproducibility of organic photovoltaic cell performance is one of the essential issues that must be clarified before beginning serious investigations of the application of creative and challenging ideas. Second, the relationships between fill factor (FF) and process variables have been demonstrated with series and shunt resistance, and this provided a chance to understand the electrical device behavior. In the blend layer, series resistance (Rs) and shunt resistance (Rsh) were varied by controlling the morphology of the blend layer, the regioregularity of the conjugated polymer, and the thickness of the blend layer. At the interface between the cathode including PEDOT:PSS and the blend layer, cathode conductivity was controlled by varying the structure of the cathode or adding an additive. Third, we thoroughly examined possible characterization mistakes in OPVC. One significant characterization mistake is observed when the crossbar electrode geometry of OPVC using PEDOT:PSS was fabricated and characterized with illumination which is larger than the actual device area. The hypothesis to explain this overestimation was excess photo-current generated from the cell region outside the overlapped electrode area, where PEDOT:PSS plays as anode and this was clearly supported with investigations. Finally, I incorporated a creative idea, which enhances the exciton dissociation efficiency by increasing the interface area between donor and acceptor to improve the power conversion efficiency of organic photovoltaic cells. To achieve this, nanoimprint lithography was applied for interface area increase. To clarify the

  10. Performance of a passive direct ethanol fuel cell

    Science.gov (United States)

    Pereira, J. P.; Falcão, D. S.; Oliveira, V. B.; Pinto, A. M. F. R.

    2014-06-01

    Ethanol emerges as an attractive fuel since it is less toxic and has higher energy density than methanol and can be produced from biomass. Direct ethanol fuel cells (DEFCs) appear as a good choice for producing sustainable energy for portable applications. However, they are still far from attaining acceptable levels of power output, since their performance is affected by the slow electrochemical ethanol oxidation and water and ethanol crossover. In the present work, an experimental study on the performance of a passive DEFC is described. Tailored MEAs (membrane electrode assembly) with different catalyst loadings, anode diffusion layers and membranes were tested in order to select optimal working conditions at high ethanol concentrations and low ethanol crossover. The performance increased with an increase of membrane and anode diffusion layer thicknesses and anode catalyst loading. A maximum power density of 1.33 mW cm-2, was obtained using a Nafion 117 membrane, 4 mg cm-2 of Pt-Ru and 2 mg cm-2 of Pt on the anode and cathode catalyst layers, ELAT as anode diffusion layer, carbon cloth as cathode diffusion layer and an ethanol concentration of 2 M. As far as the authors are aware this is the first work reporting an experimental optimization of passive DEFCs.

  11. Preliminary results for avelumab plus axitinib as first-line therapy in patients with advanced clear-cell renal-cell carcinoma (JAVELIN Renal 100): an open-label, dose-finding and dose-expansion, phase 1b trial.

    Science.gov (United States)

    Choueiri, Toni K; Larkin, James; Oya, Mototsugu; Thistlethwaite, Fiona; Martignoni, Marcella; Nathan, Paul; Powles, Thomas; McDermott, David; Robbins, Paul B; Chism, David D; Cho, Daniel; Atkins, Michael B; Gordon, Michael S; Gupta, Sumati; Uemura, Hirotsugu; Tomita, Yoshihiko; Compagnoni, Anna; Fowst, Camilla; di Pietro, Alessandra; Rini, Brian I

    2018-04-01

    The combination of an immune checkpoint inhibitor and a VEGF pathway inhibitor to treat patients with advanced renal-cell carcinoma might increase the clinical benefit of these drugs compared with their use alone. Here, we report preliminary results for the combination of avelumab, an IgG1 monoclonal antibody against the programmed cell death protein ligand PD-L1, and axitinib, a VEGF receptor inhibitor approved for second-line treatment of advanced renal-cell carcinoma, in treatment-naive patients with advanced renal-cell carcinoma. The JAVELIN Renal 100 study is an ongoing open-label, multicentre, dose-finding, and dose-expansion, phase 1b study, done in 14 centres in the USA, UK, and Japan. Eligible patients were aged 18 years or older (≥20 years in Japan) and had histologically or cytologically confirmed advanced renal-cell carcinoma with clear-cell component, life expectancy of at least 3 months, an Eastern Cooperative Oncology Group performance status of 1 or less, received no previous systemic treatment for advanced renal cell carcinoma, and had a resected primary tumour. Patients enrolled into the dose-finding phase received 5 mg axitinib orally twice daily for 7 days, followed by combination therapy with 10 mg/kg avelumab intravenously every 2 weeks and 5 mg axitinib orally twice daily. Based on the pharmacokinetic data from the dose-finding phase, ten additional patients were enrolled into the dose-expansion phase and assigned to this regimen. The other patients in the dose-expansion phase started taking combination therapy directly. The primary endpoint was dose-limiting toxicities in the first 4 weeks (two cycles) of treatment with avelumab plus axitinib. Safety and antitumour activity analyses were done in all patients who received at least one dose of avelumab or axitinib. This trial is registered with ClinicalTrials.gov, number NCT02493751. Between Oct 30, 2015, and Sept 30, 2016, we enrolled six patients into the dose-finding phase and 49 into the

  12. Experimental Study and Comparison of Various Designs of Gas Flow Fields to PEM Fuel Cells and Cell Stack Performance

    International Nuclear Information System (INIS)

    Liu, Hong; Li, Peiwen; Juarez-Robles, Daniel; Wang, Kai; Hernandez-Guerrero, Abel

    2014-01-01

    In this study, a significant number of experimental tests to proton exchange membrane (PEM) fuel cells were conducted to investigate the effect of gas flow fields on fuel cell performance. Graphite plates with various flow field or flow channel designs, from literature survey and also novel designs by the authors, were used for the PEM fuel cell assembly. The fabricated fuel cells have an effective membrane area of 23.5 cm 2 . The results showed that the serpentine flow channel design is still favorable, giving the best single fuel cell performance amongst all the studied flow channel designs. A novel symmetric serpentine flow field was proposed for a relatively large sized fuel cell application. Four fuel cell stacks each including four cells were assembled using different designs of serpentine flow channels. The output power performances of fuel cell stacks were compared and the novel symmetric serpentine flow field design is recommended for its very good performance.

  13. Preliminary Performance Data on Westinghouse Electronic Power Regulator Operating on J34-WE-32 Turbojet Engine in Altitude Wind Tunnel

    Science.gov (United States)

    Ketchum, James R.; Blivas, Darnold; Pack, George J.

    1950-01-01

    The behavior of the Westinghouse electronic power regulator operating on a J34-WE-32 turbojet engine was investigated in the NACA Lewis altitude wind tunnel at the request of the Bureau of Aeronautics, Department of the Navy. The object of the program was to determine the, steady-state stability and transient characteristics of the engine under control at various altitudes and ram pressure ratios, without afterburning. Recordings of the response of the following parameters to step changes in power lever position throughout the available operating range of the engine were obtained; ram pressure ratio, compressor-discharge pressure, exhaust-nozzle area, engine speed, turbine-outlet temperature, fuel-valve position, jet thrust, air flow, turbine-discharge pressure, fuel flow, throttle position, and boost-pump pressure. Representative preliminary data showing the actual time response of these variables are presented. These data are presented in the form of reproductions of oscillographic traces.

  14. Glucose-based Biofuel Cells: Nanotechnology as a Vital Science in Biofuel Cells Performance

    Directory of Open Access Journals (Sweden)

    Hamideh Aghahosseini

    2016-07-01

    Full Text Available Nanotechnology has opened up new opportunities for the design of nanoscale electronic devices suitable for developing high-performance biofuel cells. Glucose-based biofuel cells as green energy sources can be a powerful tool in the service of small-scale power source technology as it provides a latent potential to supply power for various implantable medical electronic devices. By using physiologically produced glucose as a fuel, the living battery can recharge for continuous production of electricity. This review article presents how nanoscience, engineering and medicine are combined to assist in the development of renewable glucose-based biofuel cell systems. Here, we review recent advances and applications in both abiotic and enzymatic glucose biofuel cells with emphasis on their “implantable” and “implanted” types. Also the challenges facing the design and application of glucose-based biofuel cells to convert them to promising replacement candidates for non-rechargeable lithium-ion batteries are discussed. Nanotechnology could make glucose-based biofuel cells cheaper, lighter and more efficient and hence it can be a part of the solutions to these challenges.

  15. Organic photovoltaic cells: from performance improvement to manufacturing processes.

    Science.gov (United States)

    Youn, Hongseok; Park, Hui Joon; Guo, L Jay

    2015-05-20

    Organic photovoltaics (OPVs) have been pursued as a next generation power source due to their light weight, thin, flexible, and simple fabrication advantages. Improvements in OPV efficiency have attracted great attention in the past decade. Because the functional layers in OPVs can be dissolved in common solvents, they can be manufactured by eco-friendly and scalable printing or coating technologies. In this review article, the focus is on recent efforts to control nanomorphologies of photoactive layer and discussion of various solution-processed charge transport and extraction materials, to maximize the performance of OPV cells. Next, recent works on printing and coating technologies for OPVs to realize solution processing are reviewed. The review concludes with a discussion of recent advances in the development of non-traditional lamination and transfer method towards highly efficient and fully solution-processed OPV. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Performance of denitrifying microbial fuel cell with biocathode over nitrite

    Directory of Open Access Journals (Sweden)

    Zhao eHuimin

    2016-03-01

    Full Text Available Microbial fuel cell (MFC with nitrite as an electron acceptor in cathode provided a new technology for nitrogen removal and electricity production simultaneously. The influences of influent nitrite concentration and external resistance on the performance of denitrifying MFC were investigated. The optimal effectiveness were obtained with the maximum total nitrogen (TN removal rate of 54.80±0.01 g m-3 d-1. It would be rather desirable for the TN removal than electricity generation at lower external resistance. Denaturing gradient gel electrophoresis suggested that Proteobacteria was the predominant phylum, accounting for 35.72%. Thiobacillus and Afipia might benefit to nitrite removal. The presence of nitrifying Devosia indicated that nitrite was oxidized to nitrate via a biochemical mechanism in the cathode. Ignavibacterium and Anaerolineaceae was found in the cathode as a heterotrophic bacterium with sodium acetate as substrate, which illustrated that sodium acetate in anode was likely permeated through proton exchange membrane to the cathode .

  17. Analysis of cell performance and thermal regeneration of a lithium-tin cell having an immobilized fused-salt electrolyte

    Science.gov (United States)

    Cairns, E. J.; Shimotake, H.

    1969-01-01

    Cell performance and thermal regeneration of a thermally regenerative cell uses lithium and tin and a fused-salt electrolyte. The emf of the Li-Sn cell, as a function of cathode-alloy composition, is shown to resemble that of the Na-Bi cell.

  18. A Cs-137 afterloading device. Preliminary results of cell kinetic effects of low dose-rate irradiation in an experimental tumour

    International Nuclear Information System (INIS)

    Rutgers, D.H.

    1988-01-01

    A Cs-137 afterloading technique is described which can be used in experimental tumours. Preliminary results, obtained with the human cervical carcinoma ME-180 xenografted to nude athymic mice, demonstrated that 20 Gy of low dose-rate irradiation induced an important redistribution of cells over cell cycle. The proportion of cells in G2-phase increased from 14.4% to 44.2% at 140 hours after irradiation. This method allows an accurate calculation of the dose-rate distribution in the tumour. Investigations of the cell kinetic effects of low dose-rate irradiation, at different dose-rates and different total doses, are therefore facilitated by the technique. (orig.) [de

  19. Preliminary performance assessment for the Waste Isolation Pilot Plant, December 1992. Vol. 1: Third comparison with 40 CFR 191, Subpart B

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1992-12-15

    Before disposing of transuranic radioactive wastes in the Waste Isolation Pilot Plant (WIPP), the United States Department of Energy (DOE) must evaluate compliance with applicable long-term regulations of the United States Environmental Protection Agency (EPA). Sandia National Laboratories is conducting iterative performance assessments of the WIPP for the DOE to provide interim guidance while preparing for final compliance evaluations. This volume contains an overview of WIPP performance assessment and a preliminary comparison with the long-term requirements of the Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes (40 CFR 191, Subpart B). Detailed information about the technical basis for the preliminary comparison is contained in Volume 2. The reference data base and values for input parameters used in the modeling system are contained in Volume 3. Uncertainty and sensitivity analyses related to 40 CFR 191B are contained in Volume 4. Volume 5 contains uncertainty and sensitivity analyses of gas and brine migration for undisturbed performance. Finally, guidance derived from the entire 1992 performance assessment is presented in Volume 6. Results of the 1992 performance assessment are preliminary, and are not suitable for final comparison with 40 CFR 191, Subpart B. Portions of the modeling system and the data base remain incomplete, and the level of confidence in the performance estimates is not sufficient for a defensible compliance evaluation. Results are, however, suitable for providing guidance to the WIPP Project. All results are conditional on the models and data used, and are presented for preliminary comparison to the Containment Requirements of 40 CFR 191, Subpart B as mean complementary cumulative distribution functions (CCDFs) displaying estimated probabilistic releases of radionuclides to the accessible environment. Results compare three conceptual models for

  20. Preliminary performance assessment for the Waste Isolation Pilot Plant, December 1992. Vol. 1: Third comparison with 40 CFR 191, Subpart B

    International Nuclear Information System (INIS)

    1992-12-01

    Before disposing of transuranic radioactive wastes in the Waste Isolation Pilot Plant (WIPP), the United States Department of Energy (DOE) must evaluate compliance with applicable long-term regulations of the United States Environmental Protection Agency (EPA). Sandia National Laboratories is conducting iterative performance assessments of the WIPP for the DOE to provide interim guidance while preparing for final compliance evaluations. This volume contains an overview of WIPP performance assessment and a preliminary comparison with the long-term requirements of the Environmental Radiation Protection Standards for Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes (40 CFR 191, Subpart B). Detailed information about the technical basis for the preliminary comparison is contained in Volume 2. The reference data base and values for input parameters used in the modeling system are contained in Volume 3. Uncertainty and sensitivity analyses related to 40 CFR 191B are contained in Volume 4. Volume 5 contains uncertainty and sensitivity analyses of gas and brine migration for undisturbed performance. Finally, guidance derived from the entire 1992 performance assessment is presented in Volume 6. Results of the 1992 performance assessment are preliminary, and are not suitable for final comparison with 40 CFR 191, Subpart B. Portions of the modeling system and the data base remain incomplete, and the level of confidence in the performance estimates is not sufficient for a defensible compliance evaluation. Results are, however, suitable for providing guidance to the WIPP Project. All results are conditional on the models and data used, and are presented for preliminary comparison to the Containment Requirements of 40 CFR 191, Subpart B as mean complementary cumulative distribution functions (CCDFs) displaying estimated probabilistic releases of radionuclides to the accessible environment. Results compare three conceptual models for

  1. Performance of Photovoltaic Modules of Different Solar Cells

    Directory of Open Access Journals (Sweden)

    Ankita Gaur

    2013-01-01

    Full Text Available In this paper, an attempt of performance evaluation of semitransparent and opaque photovoltaic (PV modules of different generation solar cells, having the maximum efficiencies reported in the literature at standard test conditions (STC, has been carried out particularly for the months of January and June. The outdoor performance is also evaluated for the commercially available semitransparent and opaque PV modules. Annual electrical energy, capitalized cost, annualized uniform cost (unacost, and cost per unit electrical energy for both types of solar modules, namely, semitransparent and opaque have also been computed along with their characteristics curves. Semitransparent PV modules have shown higher efficiencies compared to the opaque ones. Calculations show that for the PV modules made in laboratory, CdTe exhibits the maximum annual electrical energy generation resulting into minimum cost per unit electrical energy, whereas a-Si/nc-Si possesses the maximum annual electrical energy generation giving minimum cost per unit electrical energy when commercially available solar modules are concerned. CIGS has shown the lowest capitalized cost over all other PV technologies.

  2. Performance and Safety Tests on Samsung 18650 Li-ion Cells: Two Cell Designs

    Science.gov (United States)

    Deng, Yi; Jeevarajan, Judith; Rehm, Raymond; Bragg, Bobby; Zhang, Wenlin

    2002-01-01

    In order to meet the applications for space shuttle in future, two types of Samsung cells, with capacity 1800 mAh and 2000 mAh, have been investigated. The studies focused on: (1) Performance tests: completed 250 cycles at various combinations of charge/discharge C rates and discharge capacity measurements at various temperatures; and (2) Safety tests: overcharge and overdischarge, heat abuse, short circuit, internal and external short, and vibration, vacuum, and drop tests

  3. Optimum Performance of Direct Hydrogen Hybrid Fuel Cell Vehicles

    OpenAIRE

    Zhao, Hengbing; Burke, Andy

    2009-01-01

    Proton Exchange Membrane fuel cell (PEMFC) technology is one of the most attractive candidates for transportation applications due to its inherently high efficiency and high power density. However, the fuel cell system efficiency can suffer because of the need for forced air supply and water-cooling systems. Hence the operating strategy of the fuel cell system can have a significant impact on the fuel cell system efficiency and thus vehicle fuel economy. The key issues are how the fuel cell b...

  4. Application of biocathode in microbial fuel cells: cell performance and microbial community

    Energy Technology Data Exchange (ETDEWEB)

    Guo-Wei, Chen [Pusan National Univ. (Korea). Dept. of Environmental Engineering; Hefei Univ. of Technology (China). School of Civil Engineering; Choi, Soo-Jung; Lee, Tae-Ho; Lee, Gil-Young; Cha, Jae-Hwan; Kim, Chang-Won [Pusan National Univ. (Korea). Dept. of Environmental Engineering

    2008-06-15

    Instead of the utilization of artificial redox mediators or other catalysts, a biocathode has been applied in a two-chamber microbial fuel cell in this study, and the cell performance and microbial community were analyzed. After a 2-month startup, the microorganisms of each compartment in microbial fuel cell were well developed, and the output of microbial fuel cell increased and became stable gradually, in terms of electricity generation. At 20 ml/min flow rate of the cathodic influent, the maximum power density reached 19.53 W/m{sup 3}, while the corresponding current and cell voltage were 15.36 mA and 223 mV at an external resistor of 14.9 {omega}, respectively. With the development of microorganisms in both compartments, the internal resistance decreased from initial 40.2 to 14.0 {omega}, too. Microbial community analysis demonstrated that five major groups of the clones were categorized among those 26 clone types derived from the cathode microorganisms. Betaproteobacteria was the most abundant division with 50.0% (37 of 74) of the sequenced clones in the cathode compartment, followed by 21.6% (16 of 74) Bacteroidetes, 9.5% (7 of 74) Alphaproteobacteria, 8.1% (6 of 74) Chlorobi, 4.1% (3 of 74) Deltaproteobacteria, 4.1% (3 of 74) Actinobacteria, and 2.6% (2 of 74) Gammaproteobacteria. (orig.)

  5. Study of radial segregation during solidification-technical performance and preliminary results from a GAS payload on STS108

    Science.gov (United States)

    Holm, P.; Loth, K.; Larsson, B.; Carlberg, T.

    The WIS (Weak convection Influencing radial Segregation) payload was built under contract from European Space Agency (ESA) and was flown in a Get Away Special payload on Endeavour STS108 in December 2001. The experiment payload is developed and built by Swedish Space Corporation (SSC). The Principal Investigator is Dr T. Carlberg from Mid Sweden University. The intention with the experiment was to investigate the influence of weak convection, caused by surface tension forces, on radial segregation occurring in crystals grown under microgravity conditions. The geometry studied was a Bridgman configuration with a partially coated surface. The presentation will focus on the experimental technique in detail, including experiences and technical results as well as preliminary scientific results obtained during the flight. The core of the experiment equipment are seven ellipsoidal mirror furnaces with a sample processed in each furnace. The heat source was a 340 W halogen lamp with an axial oriented filament, which was positioned in one of the focal points. In the other focal point, the heating power was concentrated directly to the top of the sample rod. The advantage with this type of furnace is that there is no need for a crucible to heat the sample, which provides less mass and a faster thermal reaction. It also gives the advantage to easy achieve and control a directional melting and solidification.. The sample rods were made of Antimony doped with Tin. The rods (32 x Ø7 mm) were covered with quartz glass tubes with openings of different sizes on the envelope surface in order to induce weak convection. For the thermal control a thermocouple was mounted in the solid part of the sample rod. Each sample was contained in a sample holder with a pressure tight ampoule, pressurized with Argon at 1Atm. The sample holder was mounted directly into the bottom of the furnace. A PC/104 computer based electronic system was used for management and control of the experiment. The

  6. Fully Coupled Simulation of Lithium Ion Battery Cell Performance

    Energy Technology Data Exchange (ETDEWEB)

    Trembacki, Bradley L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Murthy, Jayathi Y. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Roberts, Scott Alan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-09-01

    Lithium-ion battery particle-scale (non-porous electrode) simulations applied to resolved electrode geometries predict localized phenomena and can lead to better informed decisions on electrode design and manufacturing. This work develops and implements a fully-coupled finite volume methodology for the simulation of the electrochemical equations in a lithium-ion battery cell. The model implementation is used to investigate 3D battery electrode architectures that offer potential energy density and power density improvements over traditional layer-by-layer particle bed battery geometries. Advancement of micro-scale additive manufacturing techniques has made it possible to fabricate these 3D electrode microarchitectures. A variety of 3D battery electrode geometries are simulated and compared across various battery discharge rates and length scales in order to quantify performance trends and investigate geometrical factors that improve battery performance. The energy density and power density of the 3D battery microstructures are compared in several ways, including a uniform surface area to volume ratio comparison as well as a comparison requiring a minimum manufacturable feature size. Significant performance improvements over traditional particle bed electrode designs are observed, and electrode microarchitectures derived from minimal surfaces are shown to be superior. A reduced-order volume-averaged porous electrode theory formulation for these unique 3D batteries is also developed, allowing simulations on the full-battery scale. Electrode concentration gradients are modeled using the diffusion length method, and results for plate and cylinder electrode geometries are compared to particle-scale simulation results. Additionally, effective diffusion lengths that minimize error with respect to particle-scale results for gyroid and Schwarz P electrode microstructures are determined.

  7. Preliminary analysis of compound systems based on high temperature fuel cell, gas turbine and Organic Rankine Cycle

    Science.gov (United States)

    Sánchez, D.; Muñoz de Escalona, J. M.; Monje, B.; Chacartegui, R.; Sánchez, T.

    This article presents a novel proposal for complex hybrid systems comprising high temperature fuel cells and thermal engines. In this case, the system is composed by a molten carbonate fuel cell with cascaded hot air turbine and Organic Rankine Cycle (ORC), a layout that is based on subsequent waste heat recovery for additional power production. The work will credit that it is possible to achieve 60% efficiency even if the fuel cell operates at atmospheric pressure. The first part of the analysis focuses on selecting the working fluid of the Organic Rankine Cycle. After a thermodynamic optimisation, toluene turns out to be the most efficient fluid in terms of cycle performance. However, it is also detected that the performance of the heat recovery vapour generator is equally important, what makes R245fa be the most interesting fluid due to its balanced thermal and HRVG efficiencies that yield the highest global bottoming cycle efficiency. When this fluid is employed in the compound system, conservative operating conditions permit achieving 60% global system efficiency, therefore accomplishing the initial objective set up in the work. A simultaneous optimisation of gas turbine (pressure ratio) and ORC (live vapour pressure) is then presented, to check if the previous results are improved or if the fluid of choice must be replaced. Eventually, even if system performance improves for some fluids, it is concluded that (i) R245fa is the most efficient fluid and (ii) the operating conditions considered in the previous analysis are still valid. The work concludes with an assessment about safety-related aspects of using hydrocarbons in the system. Flammability is studied, showing that R245fa is the most interesting fluid also in this regard due to its inert behaviour, as opposed to the other fluids under consideration all of which are highly flammable.

  8. Stability and Performance of Oxygen Electrodes for Reversible Solid Oxide Cells

    Science.gov (United States)

    Railsback, Justin Gary

    Worldwide, governments are beginning to take action to reduce anthropogenic CO2 emissions in order to mitigate the extent of global climate change. The largest fraction of global CO2 emission comes from electrical power generation, which is rapidly being converted to wind and solar installations. The intermittent nature of renewable resources requires that large scale energy storage be implemented to ensure grid stability. Pumped hydro storage is currently the only technology available for large scale energy storage; however, pumped hydro remains geographically confined and susceptible to seasonal fluctuations and offers limited discharge hours. Recent system level models predict that reversible solid oxide cells may be a competitive solution, but two key advancements are required to realize the technology: low cell resistance (cell resistance, and when a cell is operated in electrolysis the oxygen electrode is known to degrade quickly. This work focuses on both aspects of the oxygen electrode. A Pr2NiO4 based electrode is developed that has improved phase stability and good polarization resistance ( 0.1 O•cm2 at 650 °C). The electrode is prepared by wet chemical impregnation (infiltration) of Pr2NiO4 precursors into a La0.9Sr 0.1Ga0.8Mg0.2O3 scaffold. Electrochemical data for a number cells is presented and the number of infiltrations is optimized. Preliminary life tests and x-ray data are presented. Pressurization of the oxygen electrode is predicted to decrease its polarization resistance and pressurization of the reversible solid oxide cell system is desirable to achieve high round-trip efficiency. The electrochemical performance of mixed electronic-ionic conducting electrodes has not been reported above 1 atm. Four candidate electrodes are examined under pressurization up to 10 atm: Pr2NiO4 infiltrated La0.9Sr0.1 Ga0.8Mg0.2O3, Sm0.5Sr 0.5CoO3 infiltrated Ce0.9Gd0.1O 2, single phase La0.6Sr0.4Co0.2Fe 0.8O3, and single phase Nd2NiO4. The role of the ion

  9. Hematogenous osteoarticular infections of the hand and the wrist in children with sickle cell anemia: preliminary report.

    Science.gov (United States)

    Tordjman, Daniel; Holvoet, Laurent; Benkerrou, Malika; Ilharreborde, Brice; Mazda, Keyvan; Penneçot, Georges F; Fitoussi, Frank

    2014-01-01

    Hematogenous osteoarticular infections of the hand and the wrist in children with sickle cell anemia are rare and no specific studies for this location have been published. This retrospective and comparative study reviewed 34 children who carry the diagnosis of osteoarticular infections of the wrist and the hand at our institution during a 10-year period extending from January 2000 to December 2010. The first group included 8 patients with sickle cell anemia (Hg SS). The second group or control group included 26 children without sickle cell disease or any immune deficiency. Differences between groups were established by χ tests. The most common site of osteomyelitis for the sickle cell group was the metacarpals and the fingers phalanx (87.5%) whereas the most common site for the control group was the wrist and the carpus (96.2%; P<0.005).The most common pathogens responsible for osteomyelitis was Salmonella sp. (37.5%) for children with SCD, whereas it was Staphylococcus aureus (70%) for the nonsicklers. There was a significant difference between both groups regarding the treatment. Indeed, a surgical procedure was needed for the sickle cell group in all cases (100%) whereas a surgical debridement was needed in only 19.2% patients in the control group (P<0.001). At long-term follow-up, there were more long-term complications in the sickle cell group (62.5%) with epiphysiodesis of the metacarpals and metacarpophalangeal joint destruction whereas only 11.5% cases with complications were present in the control group including distal ulna epiphysiodesis, proximal interphalangeal joint stiffness, and a central radius epiphysiodesis (P<0.004). Our results confirm the severity of hand osteomyelitis in patients with sickle cell disease. A systematic approach is needed to perform early diagnosis and treatment. Identification of the causative organism is required (blood culture, bone aspiration). With antibiotic therapy, surgical treatment is the rule. Parents have to be

  10. A Prospective Randomized Study of the Radiotherapy Volume for Limited-stage Small Cell Lung Cancer: A Preliminary Report

    Directory of Open Access Journals (Sweden)

    Xiao HU

    2010-07-01

    Full Text Available Background and objective Controversies exists with regard to target volumes as far as thoracic radiotherapy (TRT is concerned in the multimodality treatment for limited-stage small cell lung cancer (LSCLC. The aim of this study is to prospectively compare the local control rate, toxicity profiles, and overall survival (OS between patients received different target volumes irradiation after induction chemotherapy. Methods LSCLC patients received 2 cycles of etoposide and cisplatin (EP induction chemotherapy and were randomly assigned to receive TRT to either the post- or pre-chemotherapy tumor extent (GTV-T as study arm and control arm, CTV-N included the positive nodal drainage area for both arms. One to 2 weeks after induction chemotherapy, 45 Gy/30 Fx/19 d TRT was administered concurrently with the third cycle of EP regimen. After that, additional 3 cycles of EP consolidation were administered. Prophylactic cranial irradiation (PCI was administered to patients with a complete response. Results Thirty-seven and 40 patients were randomly assigned to study arm and control arm. The local recurrence rates were 32.4% and 28.2% respectively (P=0.80; the isolated nodal failure (INF rate were 3.0% and 2.6% respectively (P=0.91; all INF sites were in the ipsilateral supraclavicular fossa. Medastinal N3 disease was the risk factor for INF (P=0.02, OR=14.13, 95%CI: 1.47-136.13. During radiotherapy, grade I, II weight loss was observed in 29.4%, 5.9% and 56.4%, 7.7% patients respectively (P=0.04. Grade 0-I and II-III late pulmonary injury was developed in 97.1%, 2.9% and 86.4%, 15.4% patients respectively (P=0.07. Median survival time was 22.1 months and 26.9 months respectively. The 1 to 3-year OS were 77.9%, 44.4%, 37.3% and 75.8%, 56.3%, 41.7% respectively (P=0.79. Conclusion The preliminary results of this study indicate that irradiant the post-chemotherapy tumor extent (GTV-T and positive nodal drainage area did not decrease local control and overall

  11. Cell outage compensation in LTE networks: Algorithms and performance assessment

    NARCIS (Netherlands)

    Amirijoo, M.; Jorguseski, L.; Litjens, R.; Schmelz, L.C.

    2011-01-01

    Cell outage compensation is a self-healing function and as such part of the Self-Organising Networks concept for mobile wireless networks. It aims at mitigating the degradation of coverage, capacity and service quality caused by a cell or site level outage. Upon detection of such an outage, cell

  12. Contribution of Nanostructures in High Performance Solar Cells

    Science.gov (United States)

    Aly, Abouelmaaty M.; Ebrahim, Essamudin A.; Sweelem, Emad

    2017-11-01

    Nanotechnology has great contributions in various fields, especially in solar energy conversion through solar cells (SCs). Nanostructured SCs can provide high performance with lower fabrication costs. The transition from fossil fuel energy to renewable sustainable energy represents a major technological challenge for the world. In the last years, the industry of SCs has grown rapidly due to strong attention in renewable energy in order to handle the problem of global climate change that is now believed to occur due to use of the fossil fuels. Cost is an influential factor in the eventual success of any solar technology, since inexpensive SCs are needed to produce electricity, especially for rural areas and for third world countries. Therefore, new developments in nanotechnology may open the door for the production of inexpensive and more efficient SCs by reducing the manufacturing costs of SCs. Utilizing nanotechnology in cheaper SCs will help maintain the environment. This article covers a review of the progress that has been made to-date to enhance efficiencies of various nanostructures used in SCs, including utilizations of all the wavelengths present in of the solar spectrum.

  13. Strategies toward High Performance Organic Photovoltaic Cell: Material and Process

    Science.gov (United States)

    Kim, Bong Gi

    The power conversion efficiency of organic photovoltaic (OPV) cells has been rapidly improved during the last few years and currently reaches around 10 %. The performance is evenly governed by absorption, exciton diffusion, exciton dissociation, carrier transfer, and collection efficiencies. Establishing a better understanding of OPV device physics combined with the development of new materials for each executive step contributes to this dramatic improvement. This dissertation focuses mainly on material design and development to correlate the intrinsic properties of organic semiconductors and the OPV performance. The introductory Chapter 1 briefly reviews the motivation of OPV research, its working mechanism, and representative organic materials for OPV application. Chapter 2 discusses the modulation of conjugated polymer's (CP's) absorption behavior and an efficient semi-empirical approach to predict CP's energy levels from its constituent monomers' HOMO/LUMO values. A strong acceptor lowered both the HOMO and LUMO levels of the CP, but the LUMO dropped more rapidly which ultimately produced a narrowed band-gap in the electron donating/accepting alternating copolymer system. In addition, the energy level difference between the CP and the constituent monomers converged to a constant value, providing an energy level prediction tool. Chapter 3 illustrates the systematic investigation on the relationship between the molecular structure of an energy harvesting organic dye and the exciton dissociation efficiency. The study showed that the quantum yield decreased as the exciton binding energy increases, and dipole moment direction should be properly oriented in the dye framework in order to improve photo-current generation when used in a dye sensitized photovoltaic device. Chapter 4 demonstrates the ultrasonic-assisted self-assembly of CPs in solution, rapidly and efficiently. Ultrasonication combined with dipolar media accelerated CP's aggregation, and the effect of CP

  14. Systems, methods and computer-readable media for modeling cell performance fade of rechargeable electrochemical devices

    Science.gov (United States)

    Gering, Kevin L

    2013-08-27

    A system includes an electrochemical cell, monitoring hardware, and a computing system. The monitoring hardware periodically samples performance characteristics of the electrochemical cell. The computing system determines cell information from the performance characteristics of the electrochemical cell. The computing system also develops a mechanistic level model of the electrochemical cell to determine performance fade characteristics of the electrochemical cell and analyzing the mechanistic level model to estimate performance fade characteristics over aging of a similar electrochemical cell. The mechanistic level model uses first constant-current pulses applied to the electrochemical cell at a first aging period and at three or more current values bracketing a first exchange current density. The mechanistic level model also is based on second constant-current pulses applied to the electrochemical cell at a second aging period and at three or more current values bracketing the second exchange current density.

  15. High Performance Fuel Cell and Electrolyzer Membrane Electrode Assemblies (MEAs) for Space Energy Storage Systems

    Science.gov (United States)

    Valdez, Thomas I.; Billings, Keith J.; Kisor, Adam; Bennett, William R.; Jakupca, Ian J.; Burke, Kenneth; Hoberecht, Mark A.

    2012-01-01

    Regenerative fuel cells provide a pathway to energy storage system development that are game changers for NASA missions. The fuel cell/ electrolysis MEA performance requirements 0.92 V/ 1.44 V at 200 mA/cm2 can be met. Fuel Cell MEAs have been incorporated into advanced NFT stacks. Electrolyzer stack development in progress. Fuel Cell MEA performance is a strong function of membrane selection, membrane selection will be driven by durability requirements. Electrolyzer MEA performance is catalysts driven, catalyst selection will be driven by durability requirements. Round Trip Efficiency, based on a cell performance, is approximately 65%.

  16. Effects of dissolved iron and chromium on the performance of direct methanol fuel cell

    International Nuclear Information System (INIS)

    Chen, Weimin; Xin, Qin; Sun, Gongquan; Yang, Shaohua; Zhou, Zhenhua; Mao, Qing; Sun, Pichang

    2007-01-01

    Effects of Fe 3+ and Cr 3+ ions on the performance of direct methanol fuel cell were investigated. The results show that the cell performance decreased remarkably when the concentration of Fe 3+ or Cr 3+ exceeded 1 x 10 -4 mol L -1 . Fe 3+ displayed a strong negative effect on the catalytic oxidation of methanol, while Cr 3+ affected the cell performance primarily by exchanging with protons of the membrane/ionomer and resulted in ionic conductivity losses. Complete recovery of the cell performance was not obtained after flushing the cell with deionized water

  17. Performance of planar single cell lanthanum gallate based solid oxide fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Maffei, N.; Kuriakose, A.K. [Materials Technology Labs., CANMET, Natural Resources Canada, Ottawa, ON (Canada)

    1998-09-01

    A novel synthesis of high purity, single phase strontium-magnesium doped lanthanum gallate through a nitrate route is described. The prepared powder is formed into planar monolithic elements by uniaxial pressing followed by isostatic pressing and sintering. XRD analysis of the sintered elements reveal no detectable secondary phases. The performance of the electrolyte in solid oxide fuel cells (SOFC) with three different anode/cathode combinations tested at 700 C with respect to the J-V and power density is reported. The data show that the characteristics of this SOFC are strongly dependent on the particular anode/cathode system chosen. (orig.)

  18. Performance of planar single cell lanthanum gallate based solid oxide fuel cells

    Science.gov (United States)

    Maffei, N.; Kuriakose, A. K.

    A novel synthesis of high purity, single phase strontium-magnesium doped lanthanum gallate through a nitrate route is described. The prepared powder is formed into planar monolithic elements by uniaxial pressing followed by isostatic pressing and sintering. XRD analysis of the sintered elements reveal no detectable secondary phases. The performance of the electrolyte in solid oxide fuel cells (SOFC) with three different anode/cathode combinations tested at 700°C with respect to the J- V and power density is reported. The data show that the characteristics of this SOFC are strongly dependent on the particular anode/cathode system chosen.

  19. Performance of a vanadium redox flow battery with tubular cell design

    Science.gov (United States)

    Ressel, Simon; Laube, Armin; Fischer, Simon; Chica, Antonio; Flower, Thomas; Struckmann, Thorsten

    2017-07-01

    We present a vanadium redox flow battery with a tubular cell design which shall lead to a reduction of cell manufacturing costs and the realization of cell stacks with reduced shunt current losses. Charge/discharge cycling and polarization curve measurements are performed to characterize the single test cell performance. A maximum current density of 70 mAcm-2 and power density of 142 Wl-1 (per cell volume) is achieved and Ohmic overpotential is identified as the dominant portion of the total cell overpotential. Cycling displays Coulomb efficiencies of ≈95% and energy efficiencies of ≈55%. During 113 h of operation a stable Ohmic cell resistance is observed.

  20. Performance study of solar cell arrays based on a Trough Concentrating Photovoltaic/Thermal system

    International Nuclear Information System (INIS)

    Li, Ming; Ji, Xu; Li, Guoliang; Wei, Shengxian; Li, YingFeng; Shi, Feng

    2011-01-01

    Highlights: → The performances of solar cell arrays based on a Trough Concentrating Photovoltaic/Thermal (TCPV/T) system have been studied. → The optimum concentration ratios for the single crystalline silicon cell, the Super cells and the GaAs cells were studied by experiments. → The influences between the solar cell's performance and the series resistances, the working temperature, solar irradiation intensity were explored. - Abstract: The performances of solar cell arrays based on a Trough Concentrating Photovoltaic/Thermal (TCPV/T) system have been studied via both experiment and theoretical calculation. The I-V characteristics of the solar cell arrays and the output performances of the TCPV/T system demonstrated that among the investigated four types of solar cell arrays, the triple junction GaAs cells possessed good performance characteristics and the polysilicon cells exhibited poor performance characteristics under concentrating conditions. The optimum concentration ratios for the single crystalline silicon cell, the Super cells and the GaAs cells were also studied by experiments. The optimum concentration ratios for the single crystalline silicon cells and Super cells were 4.23 and 8.46 respectively, and the triple junction GaAs cells could work well at higher concentration ratio. Besides, some theoretical calculations and experiments were performed to explore the influences of the series resistances and the working temperature. When the series resistances R s changed from 0 Ω to 1 Ω, the maximum power P m of the single crystalline silicon, the polycrystalline silicon, the Super cell and the GaAs cell arrays decreased by 67.78%, 74.93%, 77.30% and 58.07% respectively. When the cell temperature increased by 1 K, the short circuit current of the four types of solar cell arrays decreased by 0.11818 A, 0.05364 A, 0.01387 A and 0.00215 A respectively. The research results demonstrated that the output performance of the solar cell arrays with lower

  1. A preliminary investigation into the relationship between functional movement screen scores and athletic physical performance in female team sport athletes

    Science.gov (United States)

    Schultz, AB; Callaghan, SJ; Jordan, CA; Luczo, TM; Jeffriess, MD

    2014-01-01

    There is little research investigating relationships between the Functional Movement Screen (FMS) and athletic performance in female athletes. This study analyzed the relationships between FMS (deep squat; hurdle step [HS]; in-line lunge [ILL]; shoulder mobility; active straight-leg raise [ASLR]; trunk stability push-up; rotary stability) scores, and performance tests (bilateral and unilateral sit-and-reach [flexibility]; 20-m sprint [linear speed]; 505 with turns from each leg; modified T-test with movement to left and right [change-of-direction speed]; bilateral and unilateral vertical and standing broad jumps; lateral jumps [leg power]). Nine healthy female recreational team sport athletes (age = 22.67 ± 5.12 years; height = 1.66 ± 0.05 m; body mass = 64.22 ± 4.44 kilograms) were screened in the FMS and completed the afore-mentioned tests. Percentage between-leg differences in unilateral sit-and-reach, 505 turns and the jumps, and difference between the T-test conditions, were also calculated. Spearman's correlations (p ≤ 0.05) examined relationships between the FMS and performance tests. Stepwise multiple regressions (p ≤ 0.05) were conducted for the performance tests to determine FMS predictors. Unilateral sit-and-reach positive correlated with the left-leg ASLR (r = 0.704-0.725). However, higher-scoring HS, ILL, and ASLR related to poorer 505 and T-test performance (r = 0.722-0.829). A higher-scored left-leg ASLR related to a poorer unilateral vertical and standing broad jump, which were the only significant relationships for jump performance. Predictive data tended to confirm the correlations. The results suggest limitations in using the FMS to identify movement deficiencies that could negatively impact athletic performance in female team sport athletes. PMID:25729149

  2. A preliminary investigation into the relationship between functional movement screen scores and athletic physical performance in female team sport athletes

    Directory of Open Access Journals (Sweden)

    Robert G Lockie

    2014-11-01

    Full Text Available There is little research investigating relationships between the Functional Movement Screen (FMS and athletic performance in female athletes. This study analyzed the relationships between FMS (deep squat; hurdle step [HS]; in-line lunge [ILL]; shoulder mobility; active straight-leg raise [ASLR]; trunk stability push-up; rotary stability scores, and performance tests (bilateral and unilateral sit-and-reach [flexibility]; 20-m sprint [linear speed]; 505 with turns from each leg; modified T-test with movement to left and right [change-of-direction speed]; bilateral and unilateral vertical and standing broad jumps; lateral jumps [leg power]. Nine healthy female recreational team sport athletes (age = 22.67 ± 5.12 years; height = 1.66 ± 0.05 m; body mass = 64.22 ± 4.44 kilograms were screened in the FMS and completed the afore-mentioned tests. Percentage between-leg differences in unilateral sit-and-reach, 505 turns and the jumps, and difference between the T-test conditions, were also calculated. Spearman’s correlations (p ≤ 0.05 examined relationships between the FMS and performance tests. Stepwise multiple regressions (p ≤ 0.05 were conducted for the performance tests to determine FMS predictors. Unilateral sit-and-reach positive correlated with the left-leg ASLR (r = 0.704-0.725. However, higher-scoring HS, ILL, and ASLR related to poorer 505 and T-test performance (r = 0.722-0.829. A higher-scored left-leg ASLR related to a poorer unilateral vertical and standing broad jump, which were the only significant relationships for jump performance. Predictive data tended to confirm the correlations. The results suggest limitations in using the FMS to identify movement deficiencies that could negatively impact athletic performance in female team sport athletes.

  3. Performance of Mercury Triple-Point Cells Made in Brazil

    Science.gov (United States)

    Petkovic, S. G.; Santiago, J. F. N.; Filho, R. R.; Teixeira, R. N.; Santos, P. R. F.

    2003-09-01

    Fixed-points cells are primary standards in ITS-90. They contain reference material with a purity of 99.999 % or more. The gallium in a melting-point cell, for example, can reach a purity of 99.99999 %. This level of purity is not easy to obtain. However, substances like water and mercury can be purified by means of distillation and chemical procedures. This paper presents the results of mercury triple-point cells made in Brazil that were directly compared to a mercury triple-point cell of 99.999% purity. This reference cell, made by Isotech (England), was previously compared to cells from CENAM (Mexico) and NRC (Canada) and the maximum deviation found was approximately 0.4 mK. The purification stage started with a sample of mercury 99.3 % pure, and the repeated use of both mechanical and chemical processes led to a purification grade considered good enough for calibration of standard platinum resistance thermometers. The purification procedures, the method of construction of the cell, the laboratory facilities, the comparison results and the budget of uncertainties are described in this paper. All of the cells tested have a triple-point temperature within 0.25 mK of the triple-point temperature of the Inmetro reference cell.

  4. Separator Characteristics for Increasing Performance of Microbial Fuel Cells

    KAUST Repository

    Zhang, Xiaoyuan

    2009-11-01

    Two challenges for improving the performance of air cathode, single-chamber microbial fuel cells (MFCs) include increasing Coulombic efficiency (CE) and decreasing internal resistance. Nonbiodegradable glass fiber separators between the two electrodes were shown to increase power and CE, compared to cloth separators (J-cloth) that were degraded over time. MFCtestswereconductedusing glass fibermatswith thicknesses of 1.0mm (GF1) or 0.4 mm (GF0.4), a cation exchange membrane (CEM), and a J-cloth (JC), using reactors with different configurations. Higher power densities were obtained with either GF1 (46 ± 4 W/m3) or JC (46 ± 1 W/m3) in MFCs with a 2 cm electrode spacing, when the separator was placed against the cathode (S-configuration), rather than MFCs with GF0.4 (36 ± 1 W/m3) or CEM (14 ± 1 W/m3). Power was increased to 70 ± 2 W/m3 by placing the electrodes on either side of the GF1 separator (single separator electrode assembly, SSEA) and further to 150 ± 6 W/m3 using two sets of electrodes spaced 2 cm a part (double separator electrode assembly, DSEA). Reducing the DSEA electrode spacing to 0.3 cm increased power to 696 ± 26 W/m3 as a result of a decrease in the ohmic resistance from 5.9 to 2.2 Ω. The main advantages of a GF1 separator compared to JC were an improvement in the CE from 40% to 81% (S-configuration), compared to only 20-40% for JC under similar conditions, and the fact that GF1 was not biodegradable. The high CE for the GF1 separator was attributed to a low oxygen mass transfer coefficient (ko ) 5.0 x 10-5 cm/s). The GF1 andJCmaterials differed in the amount of biomass that accumulated on the separator and its biodegradability, which affected long-term power production and oxygen transport. These results show that materials and mass transfer properties of separators are important factors for improving power densities, CE, and long-term performance of MFCs. © 2009 American Chemical Society.

  5. Brain iron overload, insulin resistance, and cognitive performance in obese subjects: a preliminary MRI case-control study.

    Science.gov (United States)

    Blasco, Gerard; Puig, Josep; Daunis-I-Estadella, Josep; Molina, Xavier; Xifra, Gemma; Fernández-Aranda, Fernando; Pedraza, Salvador; Ricart, Wifredo; Portero-Otín, Manuel; Fernández-Real, José Manuel

    2014-11-01

    The linkage among the tissue iron stores, insulin resistance (IR), and cognition remains unclear in the obese population. We aimed to identify the factors that contribute to increased hepatic iron concentration (HIC) and brain iron overload (BIO), as evaluated by MRI, and to evaluate their impact on cognitive performance in obese and nonobese subjects. We prospectively recruited 23 middle-aged obese subjects without diabetes (13 women; age 50.4 ± 7.7 years; BMI 43.7 ± 4.48 kg/m2) and 20 healthy nonobese volunteers (10 women; age 48.8 ± 9.5 years; BMI 24.3 ± 3.54 kg/m2) in whom iron load was assessed in white and gray matter and the liver by MRI. IR was measured from HOMA-IR and an oral glucose tolerance test. A battery of neuropsychological tests was used to evaluate the cognitive performance. Multivariate regression analysis was used to identify the independent associations of BIO and cognitive performance. A significant increase in iron load was detected at the caudate nucleus (P cognitive performance. Obesity and IR may contribute to increased HIC and BIO being associated with worse cognitive performance. BIO could be a potentially useful MRI biomarker for IR and obesity-associated cognitive dysfunction. © 2014 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  6. Hypersonic research engine project. Phase 2: Preliminary report on the performance of the HRE/AIM at Mach 6

    Science.gov (United States)

    Sun, Y. H.; Sainio, W. C.

    1975-01-01

    Test results of the Aerothermodynamic Integration Model are presented. A program was initiated to develop a hydrogen-fueled research-oriented scramjet for operation between Mach 3 and 8. The primary objectives were to investigate the internal aerothermodynamic characteristics of the engine, to provide realistic design parameters for future hypersonic engine development as well as to evaluate the ground test facility and testing techniques. The engine was tested at the NASA hypersonic tunnel facility with synthetic air at Mach 5, 6, and 7. The hydrogen fuel was heated up to 1500 R prior to injection to simulate a regeneratively cooled system. The engine and component performance at Mach 6 is reported. Inlet performance compared very well both with theory and with subscale model tests. Combustor efficiencies up to 95 percent were attained at an equivalence ratio of unity. Nozzle performance was lower than expected. The overall engine performance was computed using two different methods. The performance was also compared with test data from other sources.

  7. Optimizing the fMRI data-processing pipeline using prediction and reproducibility performance metrics: I. A preliminary group analysis

    DEFF Research Database (Denmark)

    Strother, Stephen C.; Conte, Stephen La; Hansen, Lars Kai

    2004-01-01

    We argue that published results demonstrate that new insights into human brain function may be obscured by poor and/or limited choices in the data-processing pipeline, and review the work on performance metrics for optimizing pipelines: prediction, reproducibility, and related empirical Receiver......, temporal detrending, and between-subject alignment) in a group analysis of BOLD-fMRI scans from 16 subjects performing a block-design, parametric-static-force task. Large-scale brain networks were detected using a multivariate linear discriminant analysis (canonical variates analysis, CVA) that was tuned...... of baseline scans have constant, equal means, and this assumption was assessed with prediction metrics. Higher-order polynomial warps compared to affine alignment had only a minor impact on the performance metrics. We found that both prediction and reproducibility metrics were required for optimizing...

  8. A preliminary examination of neurocognitive performance and symptoms following a bout of soccer heading in athletes wearing protective soccer headbands.

    Science.gov (United States)

    Elbin, R J; Beatty, Amanda; Covassin, Tracey; Schatz, Philip; Hydeman, Ana; Kontos, Anthony P

    2015-01-01

    This study compared changes in neurocognitive performance and symptom reports following an acute bout of soccer heading among athletes with and without protective soccer headgear. A total of 25 participants headed a soccer ball 15 times over a 15-minute period, using a proper linear heading technique. Participants in the experimental group completed the heading exercise while wearing a protective soccer headband and controls performed the heading exercise without wearing the soccer headband. Neurocognitive performance and symptom reports were assessed before and after the acute bout of heading. Participants wearing the headband showed significant decreases on verbal memory (p = 0.02) compared with the no headband group, while the no headband group demonstrated significantly faster reaction time (p = 0.03) than the headband group following the heading exercise. These findings suggest that protective soccer headgear likely does not mitigate the subtle neurocognitive effects of acute soccer heading.

  9. Comparison of force, power, and striking efficiency for a Kung Fu strike performed by novice and experienced practitioners: preliminary analysis.

    Science.gov (United States)

    Neto, Osmar Pinto; Magini, Marcio; Saba, Marcelo M F; Pacheco, Marcos Tadeu Tavares

    2008-02-01

    This paper presents a comparison of force, power, and efficiency values calculated from Kung Fu Yau-Man palm strikes, when performed by 7 experienced and 6 novice men. They performed 5 palm strikes to a freestanding basketball, recorded by high-speed camera at 1000 Hz. Nonparametric comparisons and correlations showed experienced practitioners presented larger values of mean muscle force, mean impact force, mean muscle power, mean impact power, and mean striking efficiency, as is noted in evidence obtained for other martial arts. Also, an interesting result was that for experienced Kung Fu practitioners, muscle power was linearly correlated with impact power (p = .98) but not for the novice practitioners (p = .46).

  10. Fuel cell mining vehicles: design, performance and advantages

    International Nuclear Information System (INIS)

    Betournay, M.C.; Miller, A.R.; Barnes, D.L.

    2003-01-01

    The potential for using fuel cell technology in underground mining equipment was discussed with reference to the risks associated with the operation of hydrogen vehicles, hydrogen production and hydrogen delivery systems. This paper presented some of the initiatives for mine locomotives and fuel cell stacks for underground environments. In particular, it presents the test results of the first applied industrial fuel cell vehicle in the world, a mining and tunneling locomotive. This study was part of an international initiative managed by the Fuel Cell Propulsion Institute which consists of several mining companies, mining equipment manufacturers, and fuel cell technology developers. Some of the obvious benefits of fuel cells for underground mining operations include no exhaust gases, lower electrical costs, significantly reduced maintenance, and lower ventilation costs. Another advantage is that the technology can be readily automated and computer-based for tele-remote operations. This study also quantified the cost and operational benefits associated with fuel cell vehicles compared to diesel vehicles. It is expected that higher vehicle productivity could render fuel cell underground vehicles cost-competitive. 6 refs., 1 tab

  11. Recent Advances in High-Performance Direct Methanol Fuel Cells

    Science.gov (United States)

    Narayanan, S. R.; Chun, W.; Valdez, T. I.; Jeffries-Nakamura, B.; Frank, H.; Surumpudi, S.; Halpert, G.; Kosek, J.; Cropley, C.; La Conti, A. B.; hide

    1996-01-01

    Direct methanol fuel cells for portable power applications have been advanced significantly under DARPA- and ARO-sponsored programs over the last five years. A liquid-feed, direct methanol fuel cell developed under these programs, employs a proton exchange membrane as electrolyte and operates on aqueous solutions of methanol with air or oxygen as the oxidant.

  12. Performance Evaluation of Solid Oxide Fuel Cell by Computer ...

    African Journals Online (AJOL)

    The search for sustainable energy source that can compete with the existing one led to the discovery and acceptance of fuel cell technologies as a perfect replacement for fossil fuel. The ability of Solid Oxide Fuel Cells (SOFC) to capture the heat generation during the process of energy generation from electrochemical ...

  13. PRELIMINARY ESTIMATES OF PERFORMANCE AND COST OF MERCURY EMISSION CONTROL TECHNOLOGY APPLICATIONS ON ELECTRIC UTILITY BOILERS: AN UPDATE

    Science.gov (United States)

    The paper presents estimates of performance levels and related costs associated with controlling mercury (Hg) emissions from coal-fired power plants using either powdered activated carbon (PAC) injection or multipollutant control in which Hg capture is enhanced in existing and ne...

  14. Preliminary assessment of the performance of concrete as a structural material for alternative low-level radioactive waste disposal technologies

    International Nuclear Information System (INIS)

    MacKenzie, D.R.; Siskind, B.; Bowerman, B.S.; Piciulo, P.L.

    1986-12-01

    The objective of this study was to develop information needed to evaluate the long-term performance of concrete and reinforced concrete as a structural material for alternative LLW disposal methods. The capability to carry out such an evaluation is required for licensing a site which employs one of these alternative methods. The basis for achieving the study objective was the review and analysis of the literature on concrete and its properties, particularly its durability. In carrying out this program, criteria for evaluating performance of concrete and factors that can effect its performance were identified. The factors are both intrinsic, i.e., associated with composition of the concrete (and thus controllable), and extrinsic, i.e., due to external environmental forces such as climatic conditions and aggressive chemicals in the soil. A section of the report is devoted to the properties of coatings and their possible use in protecting concrete from chemical attack and enhancing its useful properties. The testing of concrete, using both accelerated tests and long-term non-accelerated tests, is discussed with special reference to its application to modeling of long-term performance prediction. On the basis of the study's results, minimum acceptance criteria are recommended as an aid in the licensing of disposal sites which make sure use of alternative methods

  15. Impact of Users Identities and Access Conditions on Downlink Performance in Closed Small-Cell Networks

    KAUST Repository

    Radaydeh, Redha; Gaaloul, Fakhreddine; Alouini, Mohamed-Slim

    2015-01-01

    This paper investigates the effect of various operation parameters on the downlink user performance in overlaid small-cell networks. The case study considers closed-access small cells (e.g., femtocells), wherein only active authorized user

  16. Cell-element simulations to optimize the performance of osmotic processes in porous membranes

    KAUST Repository

    Calo, Victor M.; Iliev, Oleg; Nunes, Suzana Pereira; Printsypar, Galina; Shi, Meixia

    2018-01-01

    concerns the design of a cell element for the forward osmosis experiments. Using the developed software tool we qualitatively and quantitatively investigate the performance of a cell element that we designed for laboratory experiments of forward osmosis

  17. Effects of distractors on upright balance performance in school-aged children with attention deficit hyperactivity disorder, preliminary study.

    Science.gov (United States)

    Aydinli, Fatma Esen; Çak, Tuna; Kirazli, Meltem Çiğdem; Çinar, Betül Çiçek; Pektaş, Alev; Çengel, Ebru Kültür; Aksoy, Songül

    2016-11-17

    Attention deficit hyperactivity disorder is a common impairing neuropsychiatric disorder with onset in early childhood. Almost half of the children with attention deficit hyperactivity disorder also experience a variety of motor-related dysfunctions ranging from fine/gross motor control problems to difficulties in maintaining balance. The main purpose of this study was to investigate the effects of distractors two different auditory distractors namely, relaxing music and white noise on upright balance performance in children with attention deficit hyperactivity disorder. We compared upright balance performance and the involvement of different sensory systems in the presence of auditory distractors between school-aged children with attention deficit hyperactivity disorder (n=26) and typically developing controls (n=20). Neurocom SMART Balance Master Dynamic Posturography device was used for the sensory organization test. Sensory organization test was repeated three times for each participant in three different test environments. The balance scores in the silence environment were lower in the attention deficit hyperactivity disorder group but the differences were not statistically significant. In addition to lower balance scores the visual and vestibular ratios were also lower. Auditory distractors affected the general balance performance positively for both groups. More challenging conditions, using an unstable platform with distorted somatosensory signals were more affected. Relaxing music was more effective in the control group, and white noise was more effective in the attention deficit hyperactivity disorder group and the positive effects of white noise became more apparent in challenging conditions. To the best of our knowledge, this is the first study evaluating balance performance in children with attention deficit hyperactivity disorder under the effects of auditory distractors. Although more studies are needed, our results indicate that auditory distractors

  18. Optimization of concentrator photovoltaic solar cell performance through photonic engineering

    Energy Technology Data Exchange (ETDEWEB)

    Harris, James [Stanford Univ., CA (United States)

    2018-04-04

    The goal of this program was to incorporate two new and innovative design concepts into the design and production of CPV cells that have near zero added cost, yet significantly increase the operational efficiency of CPV modules. The program focused developing luminescent coupling effects and radiative cooling layers to increase efficiency and suppress CPV module power losses due to spectral variations and heating. The major results of the program were: 1) The optics of three commercial refractive (Fresnel) concentrators were characterized and prevent application of radiative cooling concepts due to strong mid-IR absorption (4-12µm) required to effectively radiate blackbody radiation from the cells and provide cooling. Investigation of alternative materials for the concentrator lenses produced only undesirable options—materials with reasonable mid-IR transmission for cooling only had about 30-40 visible transmission, thus reducing incident sunlight by >50%. While our investigation was somewhat limited, our work suggests that the only viable concentrator system that can incorporate radiative cooling utilizes reflective optics. 2) With limited ability to test high concentration CPV cells (requires outdoor testing), we acquired both semi-crystalline and crystalline Si cells and tested them in our outdoor facility and demonstrated 4°C cooling using a simple silica layer coating on the cells. 3) Characterizing Si cells in the IR associated with radiative cooling, we observed very significant near-IR absorption that increases the cell operating temperature by a similar amount, 4-5°C. By appropriate surface layer design, one can produce a layer that is highly reflective in the near-IR (1.5-4µm) and highly emissive in the mid-IR (5-15µm), thus reducing cell operational temperature by 10°C and increasing efficiency by ~1% absolute. The radiative cooling effect in c-Si solar cells might be further improved by providing a higher thermal conductive elastomer for

  19. Radiation performance of AlGaAs concentrator cells and expected performance of cascade structures

    International Nuclear Information System (INIS)

    Curtis, H.B.; Swartz, C.K.; Hart, R.E. Jr.

    1987-01-01

    Aluminum gallium arsenide, GaAs, silicon and InGaAs cells have been irradiated with 1 MeV electrons and 37 MeV protons. These cells are candidates for individual cells in a cascade structure. Data is presented for both electron and proton irradiation studies for one sun and a concentration level of 100X AMO. Results of calculations on the radiation resistance of cascade cell structures based on the individual cell data are also presented. Both series connected and separately connected structures are investigated

  20. A Long-Pulse Spallation Source at Los Alamos: Facility description and preliminary neutronic performance for cold neutrons

    International Nuclear Information System (INIS)

    Russell, G.J.; Weinacht, D.J.; Pitcher, E.J.; Ferguson, P.D.

    1998-03-01

    The Los Alamos National Laboratory has discussed installing a new 1-MW spallation neutron target station in an existing building at the end of its 800-MeV proton linear accelerator. Because the accelerator provides pulses of protons each about 1 msec in duration, the new source would be a Long Pulse Spallation Source (LPSS). The facility would employ vertical extraction of moderators and reflectors, and horizontal extraction of the spallation target. An LPSS uses coupled moderators rather than decoupled ones. There are potential gains of about a factor of 6 to 7 in the time-averaged neutron brightness for cold-neutron production from a coupled liquid H 2 moderator compared to a decoupled one. However, these gains come at the expense of putting ''tails'' on the neutron pulses. The particulars of the neutron pulses from a moderator (e.g., energy-dependent rise times, peak intensities, pulse widths, and decay constant(s) of the tails) are crucial parameters for designing instruments and estimating their performance at an LPSS. Tungsten is the reference target material. Inconel 718 is the reference target canister and proton beam window material, with Al-6061 being the choice for the liquid H 2 moderator canister and vacuum container. A 1-MW LPSS would have world-class neutronic performance. The authors describe the proposed Los Alamos LPSS facility, and show that, for cold neutrons, the calculated time-averaged neutronic performance of a liquid H 2 moderator at the 1-MW LPSS is equivalent to about 1/4th the calculated neutronic performance of the best liquid D 2 moderator at the Institute Laue-Langevin reactor. They show that the time-averaged moderator neutronic brightness increases as the size of the moderator gets smaller

  1. C-arm flat-panel CT arthrography of the shoulder: Radiation dose considerations and preliminary data on diagnostic performance

    Energy Technology Data Exchange (ETDEWEB)

    Guggenberger, Roman; Ulbrich, Erika J.; Kaelin, Pascal; Pfammatter, Thomas; Alkadhi, Hatem; Andreisek, Gustav [University Hospital Zurich, Institute of Diagnostic and Interventional Radiology, Zuerich (Switzerland); Dietrich, Tobias J. [Balgrist University Hospital, Department of Radiology, Zurich (Switzerland); Scholz, Rosemarie; Koehler, Christoph; Elsaesser, Thilo [Siemens Healthcare GmbH, Business Area Advanced Therapies, Forchheim (Germany); Le Corroller, Thomas [Aix-Marseille Universite, CNRS, ISM UMR 7287, Marseille (France); Radiology Department, APHM, Marseille (France)

    2017-02-15

    To investigate radiation dose and diagnostic performance of C-arm flat-panel CT (FPCT) versus standard multi-detector CT (MDCT) shoulder arthrography using MRI-arthrography as reference standard. Radiation dose of two different FPCT acquisitions (5 and 20 s) and standard MDCT of the shoulder were assessed using phantoms and thermoluminescence dosimetry. FPCT arthrographies were performed in 34 patients (mean age 44 ± 15 years). Different joint structures were quantitatively and qualitatively assessed by two independent radiologists. Inter-reader agreement and diagnostic performance were calculated. Effective radiation dose was markedly lower in FPCT 5 s (0.6 mSv) compared to MDCT (1.7 mSv) and FPCT 20 s (3.4 mSv). Contrast-to-noise ratios (CNRs) were significantly (p < 0.05) higher in FPCT 20-s versus 5-s protocols. Inter-reader agreements of qualitative ratings ranged between κ = 0.47-1.0. Sensitivities for cartilage and rotator cuff pathologies were low for FPCT 5-s (40 % and 20 %) and moderate for FPCT 20-s protocols (75 % and 73 %). FPCT showed high sensitivity (81-86 % and 89-99 %) for bone and acromioclavicular-joint pathologies. Using a 5-s protocol FPCT shoulder arthrography provides lower radiation dose compared to MDCT but poor sensitivity for cartilage and rotator cuff pathologies. FPCT 20-s protocol is moderately sensitive for cartilage and rotator cuff tendon pathology with markedly higher radiation dose compared to MDCT. (orig.)

  2. Efficacy of Brain Gym Training on the Cognitive Performance and Fitness Level of Active Older Adults: A Preliminary Study.

    Science.gov (United States)

    Cancela, José M; Vila Suárez, Ma Helena; Vasconcelos, Jamine; Lima, Ana; Ayán, Carlos

    2015-10-01

    This study evaluates the impact of Brain Gym (BG) training in active older adults. Eighty-five participants were assigned to four training groups: BG (n = 18), BG plus water-based exercise (n = 18), land-based exercise (n = 30), and land plus water-based exercise (n = 19). The effects of the programs on the attention and memory functions were assessed by means of the symbol digit modality test. The two-min step and the eight-foot up-and-go tests were used to evaluate their impact on fitness level. No program had a significant influence on the participant's cognitive performance, while different effects on the sample' fitness levels were observed. These findings suggest that the effects of BG on the cognitive performance and fitness level of active older adults are similar to those obtained after the practice of a traditional exercise program. Whether BG is performed in isolation or combined with other exercise programs seems to have no influence on such effects.

  3. C-arm flat-panel CT arthrography of the shoulder: Radiation dose considerations and preliminary data on diagnostic performance

    International Nuclear Information System (INIS)

    Guggenberger, Roman; Ulbrich, Erika J.; Kaelin, Pascal; Pfammatter, Thomas; Alkadhi, Hatem; Andreisek, Gustav; Dietrich, Tobias J.; Scholz, Rosemarie; Koehler, Christoph; Elsaesser, Thilo; Le Corroller, Thomas

    2017-01-01

    To investigate radiation dose and diagnostic performance of C-arm flat-panel CT (FPCT) versus standard multi-detector CT (MDCT) shoulder arthrography using MRI-arthrography as reference standard. Radiation dose of two different FPCT acquisitions (5 and 20 s) and standard MDCT of the shoulder were assessed using phantoms and thermoluminescence dosimetry. FPCT arthrographies were performed in 34 patients (mean age 44 ± 15 years). Different joint structures were quantitatively and qualitatively assessed by two independent radiologists. Inter-reader agreement and diagnostic performance were calculated. Effective radiation dose was markedly lower in FPCT 5 s (0.6 mSv) compared to MDCT (1.7 mSv) and FPCT 20 s (3.4 mSv). Contrast-to-noise ratios (CNRs) were significantly (p < 0.05) higher in FPCT 20-s versus 5-s protocols. Inter-reader agreements of qualitative ratings ranged between κ = 0.47-1.0. Sensitivities for cartilage and rotator cuff pathologies were low for FPCT 5-s (40 % and 20 %) and moderate for FPCT 20-s protocols (75 % and 73 %). FPCT showed high sensitivity (81-86 % and 89-99 %) for bone and acromioclavicular-joint pathologies. Using a 5-s protocol FPCT shoulder arthrography provides lower radiation dose compared to MDCT but poor sensitivity for cartilage and rotator cuff pathologies. FPCT 20-s protocol is moderately sensitive for cartilage and rotator cuff tendon pathology with markedly higher radiation dose compared to MDCT. (orig.)

  4. Performance of mercury triple point cells made in Brazil

    OpenAIRE

    Petkovic, Slavolhub Garcia; Santiago, José Felipe Neves; Teixeira, Renato Nunes; Santos, Paulo Roberto da Fonseca

    2002-01-01

    ABSTRACT: Fixed−points cells are primary standards in ITS-90. They contain reference material with a purity of 99.999 % or more. The gallium in a melting−point cell, for example, can reach a purity of 99.99999 %. This level of purity is not easy to obtain. However, substances like water and mercury can be purified by means of distillation and chemical procedures. This paper presents the results of mercury triple−point cells made in Brazil that were directly compared to a mercury triple−point ...

  5. Final Report - Effects of Impurities on Fuel Cell Performance and Durability

    Energy Technology Data Exchange (ETDEWEB)

    Trent Molter

    2012-08-18

    This program is focused on the experimental determination of the effects of key hydrogen side impurities on the performance of PEM fuel cells. Experimental data has been leveraged to create mathematical models that predict the performance of PEM fuel cells that are exposed to specific impurity streams. These models are validated through laboratory experimentation and utilized to develop novel technologies for mitigating the effects of contamination on fuel cell performance. Results are publicly disseminated through papers, conference presentations, and other means.

  6. Performances of Saft Lithium-Ion Cells in LEO Cycling

    Directory of Open Access Journals (Sweden)

    Prevot D.

    2017-01-01

    The article will thus present the whole LEO cycling results available for the two cells, and will provide afterwards the correlation status of Saft Li-ion Model (SLIM with all the experimental data acquired.

  7. Application of Fourier transform infrared spectroscopy to biomolecular profiling of cultured fibroblast cells from Gaucher disease patients: A preliminary investigation.

    Science.gov (United States)

    Igci, Nasit; Sharafi, Parisa; Demiralp, Duygu Ozel; Demiralp, Cemil Ozerk; Yuce, Aysel; Emre, Serap Dokmeci

    2017-10-01

    Gaucher disease (GD) is defined as an autosomal recessive disorder resulting from the deficiency of glucocerebrosidase (E.C. 3.2.1.45). Glucocerebrosidase is responsible for the degradation of glucosylceramide into ceramide and glucose. The deficiency of this enzyme results in the accumulation of undegraded glucosylceramide, almost exclusively in macrophages. With Fourier transform infrared (FTIR) spectroscopy, the complete molecular diversity of the samples can be studied comparatively and the amount of the particular materials can be determined. Also, the secondary structure ratios of proteins can be determined by analysing the amide peaks. The primary aim of this study is to introduce FTIR-ATR spectroscopy technique to GD research for the first time in the literature and to assess its potential as a new molecular method. Primary fibroblast cell cultures obtained from biopsy samples were used, since this material is widely used for the diagnosis of GD. Intact cells were placed onto a FTIR-ATR crystal and dried by purging nitrogen gas. Spectra were recorded in the mid-infrared region between 4500-850 cm-1 wavenumbers. Each peak in the spectra was assigned to as organic biomolecules according to their chemical bond information. A quantitative analysis was performed using peak areas and we also used a hierarchical cluster analysis as a multivariate spectral analysis. We obtained FTIR spectra of fibroblast samples and assigned the biomolecule origins of the peaks. We observed individual heterogeneity in FTIR spectra of GD fibroblast samples, confirming the well-known phenotypic heterogeneity in GD at the molecular level. Significant alterations in protein, lipid and carbohydrate levels related to the enzyme replacement therapy were also observed, which is also supported by cluster analysis. Our results showed that the application of FTIR spectroscopy to GD research deserves more attention and detailed studies with an increased sample size in order to evaluate its

  8. A preliminary study into performing routine tube output and automatic exposure control quality assurance using radiology information system data

    International Nuclear Information System (INIS)

    Charnock, P.; Jones, R.; Fazakerley, J.; Wilde, R.; Dunn, A. F.

    2011-01-01

    Data are currently being collected from hospital radiology information systems in the North West of the UK for the purposes of both clinical audit and patient dose audit. Could these data also be used to satisfy quality assurance (QA) requirements according to UK guidance? From 2008 to 2009, 731 653 records were submitted from 8 hospitals from the North West England. For automatic exposure control QA, the protocol from Inst. of Physics and Engineering in Medicine (IPEM) report 91 recommends that milli amperes per second can be monitored for repeatability and reproducibility using a suitable phantom, at 70-81 kV. Abdomen AP and chest PA examinations were analysed to find the most common kilo voltage used with these records then used to plot average monthly milli amperes per second with time. IPEM report 91 also recommends that a range of commonly used clinical settings is used to check output reproducibility and repeatability. For each tube, the dose area product values were plotted over time for two most common exposure factor sets. Results show that it is possible to do performance checks of AEC systems; however more work is required to be able to monitor tube output performance. Procedurally, the management system requires work and the benefits to the workflow would need to be demonstrated. (authors)

  9. A Preliminary Study of Functional Brain Activation among Marijuana Users during Performance of a Virtual Water Maze Task

    Directory of Open Access Journals (Sweden)

    Jennifer Tropp Sneider

    2013-01-01

    Full Text Available Numerous studies have reported neurocognitive impairments associated with chronic marijuana use. Given that the hippocampus contains a high density of cannabinoid receptors, hippocampal-mediated cognitive functions, including visuospatial memory, may have increased vulnerability to chronic marijuana use. Thus, the current study examined brain activation during the performance of a virtual analogue of the classic Morris water maze task in 10 chronic marijuana (MJ users compared to 18 nonusing (NU comparison subjects. Imaging data were acquired using blood oxygen level-dependent (BOLD functional MRI at 3.0 Tesla during retrieval (hidden platform and motor control (visible platform conditions. While task performance on learning trials was similar between groups, MJ users demonstrated a deficit in memory retrieval. For BOLD fMRI data, NU subjects exhibited greater activation in the right parahippocampal gyrus and cingulate gyrus compared to the MJ group for the Retrieval-Motor Control contrast (NU > MJ. These findings suggest that hypoactivation in MJ users may be due to differences in the efficient utilization of neuronal resources during the retrieval of memory. Given the paucity of data on visuospatial memory function in MJ users, these findings may help elucidate the neurobiological effects of marijuana on brain activation during memory retrieval.

  10. Effect of the application of an electric field on the performance of a two-phase loop device: preliminary results

    International Nuclear Information System (INIS)

    Creatini, F; Di Marco, P; Filippeschi, S; Fioriti, D; Mameli, M

    2015-01-01

    In the last decade, the continuous development of electronics has pointed out the need for a change in mind with regard to thermal management. In the present scenario, Pulsating Heat Pipes (PHPs) are novel promising two-phase passive heat transport devices that seem to meet all present and future thermal requirements. Nevertheless, PHPs governing phenomena are quite unique and not completely understood. In particular, single closed loop PHPs manifest several drawbacks, mostly related to the reduction of device thermal performance and reliability, i.e. the occurrence of multiple operational quasi-steady states. The present research work proposes the application of an electric field as a technique to promote the circulation of the working fluid in a preferential direction and stabilize the device operation. The tested single closed loop PHP is made of a copper tube with an inner tube diameter equal to 2.00 mm and filled with pure ethanol (60% filling ratio). The electric field is generated by a couple of wire-shaped electrodes powered with DC voltage up to 20 kV and laid parallel to the longitudinal axis of the glass tube constituting the adiabatic section. Although the electric field intensity in the working fluid region is weakened both by the polarization phenomenon of the working fluid and by the interposition of the glass tube, the experimental results highlight the influence of the electric field on the device thermal performance and encourage the continuation of the research in this direction. (paper)

  11. Effects of chronic Rhodiola Rosea supplementation on sport performance and antioxidant capacity in trained male: preliminary results.

    Science.gov (United States)

    Parisi, A; Tranchita, E; Duranti, G; Ciminelli, E; Quaranta, F; Ceci, R; Cerulli, C; Borrione, P; Sabatini, S

    2010-03-01

    Rhodiola Rosea, is an adaptogen plant which has been reported to promote fatty acids utilisation, to ameliorate antioxidant function, and to improve body resistance to physical strenuous efforts. The purpose of the present study was to investigate the effects on physical performance as well as on the redox status of a chronic Rhodiola Rosea supplementation in a group of competitive athletes during endurance exercise. Following a chronic supplementation with Rhodiola Rosea for 4 weeks, 14 trained male athletes underwent a cardio-pulmonary exhaustion test and blood samples to evaluate their antioxidant status and other biochemical parameters. These data were compared with those coming from the same athletes after an intake of placebo. The evaluation of physical performance parameters showed that HR Max, Borg Scale level, VO(2) max and duration of the test were essentially unaffected by Rhodiola Rosea assumption. On the contrary, Rhodiola Rosea intake reduced, in a statistically significative manner, plasma free fatty acids levels. No effect on blood glucose was found. Blood antioxidant status and inflammatory parameters resulted unaffected by Rhodiola Rosea supplementation. Blood lactate and plasma creatine kinase levels were found significantly lower (P<0.05) in Rhodiola Rosea treated subjects when compared to the placebo treated group. Chronic Rhodiola Rosea supplementation is able to reduce both lactate levels and parameters of skeletal muscle damage after an exhaustive exercise session. Moreover this supplementation seems to ameliorate fatty acid consumption. Taken together those observation confirm that Rhodiola Rosea may increase the adaptogen ability to physical exercise.

  12. Borehole radar measurements performed on preliminary investigation areas in Finland for final disposal of spent nuclear fuel

    International Nuclear Information System (INIS)

    Carlsten, S.

    1991-05-01

    Borehole radar measurements with the RAMAC system have been performed in 24 boreholes distributed between the investigation areas Kuhmo Romuvaara, Hyrynsalmi Veitsivaara, Konginkangas Kivetty, Sievi Syyry, and Eurajoki Olkiluoto. The purpose of the borehole radar measurement program has been to investigate the bedrock in the vicinity of the boreholes in order to obtain information about geometry and extent of fracture zones, lithological contacts and other structures. The measurements have been performed as singlehole radar reflection measurements and Vertical Radar Profiling (VRP) measurements, using antennas with 22 MHz frequency range in both configurations. The total measured length in the singlehole radar reflection mode is 13304 meter and in the VRP mode 9200 meter. The VRP measurements are not presented in the report. Radar data from the singlehole reflection measurements are presented as grey scale radar maps after digital filtering with a bandpass filter and a moving average filter. Interpreted zones from the singlehole radar measurements are presented in tables for each borehole. It has been possible to study structures at distances of more than 110 meter from the borehole

  13. Influence of the genetic origin and sex on live performance and carcass traits in the rabbit. Preliminary results

    Directory of Open Access Journals (Sweden)

    Antonella Dalle Zotte

    2010-01-01

    Full Text Available The study compared the growth performance and carcass traits of 41 rabbits of both sexes derived from 3 genetic origins (GO: sire Vienna Blue (B, sire Burgundy Fawn (F and hybrid rabbits (H. From weaning they were reared indoor in bicellular cages and fed ad libitum the same pelleted diet until a fixed slaughter weight (2.8±0.11kg. The rabbits of the 3 GO differed in slaughter age (88 vs 109 vs 122d for H, B and F-GO, respectively; P<0.001. Growth performance of B was better than that of F, while that of H was better than B+F groups. Carcass traits were not modified by the GO; only perirenal fat percentage increased from H (1.2% to B (1.7% to F (2.5% of the reference carcass; P<0.05 accordingly to the slaughter age. The sex effect was significant only for the dressing out percentage, being higher in males than females (59.0 vs 57.6%; P<0.05.

  14. Performance Analysis of Air Breathing Proton Exchange Membrane Fuel Cell Stack (PEMFCS) At Different Operating Condition

    Science.gov (United States)

    Sunil, V.; Venkata siva, G.; Yoganjaneyulu, G.; Ravikumar, V. V.

    2017-08-01

    The answer for an emission free power source in future is in the form of fuel cells which combine hydrogen and oxygen producing electricity and a harmless by product-water. A proton exchange membrane (PEM) fuel cell is ideal for automotive applications. A single cell cannot supply the essential power for any application. Hence PEM fuel cell stacks are used. The effect of different operating parameters namely: type of convection, type of draught, hydrogen flow rate, hydrogen inlet pressure, ambient temperature and humidity, hydrogen humidity, cell orientation on the performance of air breathing PEM fuel cell stack was analyzed using a computerized fuel cell test station. Then, the fuel cell stack was subjected to different load conditions. It was found that the stack performs very poorly at full capacity (runs only for 30 min. but runs for 3 hours at 50% capacity). Hence, a detailed study was undertaken to maximize the duration of the stack’s performance at peak load.

  15. Preliminary plan for disposal-system characterization and long-term performance evaluation of the Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    Bertram-Howery, S.G.; Hunter, R.L.

    1989-04-01

    The US Department of Energy is planning to dispose of transuranic wastes at the Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico. Sandia National Laboratories is responsible for evaluating the compliance of the WIPP with the Environmental Protection Agency's Environmental Standards for the Management and Disposal of Spent Nuclear Fuel, High-Level and Transuranic Radioactive Wastes (40 CFR 191, Subpart B). This plan has been developed to present the issues that will be addressed before compliance can be evaluated. These issues examine the procedural nature of the Standard, and the technical requirements for further characterizing the behavior of the disposal system, including uncertainties, to support the compliance assessment. The plan briefly describes the activities that will be conducted prior to 1993 by Sandia to characterize the WIPP disposal system's behavior and predict its performance. 41 refs., 35 figs., 21 tabs

  16. Preliminary evaluation of two radioiodinated maleimide derivatives targeting peripheral and membrane sulfhydryl groups for in vitro cell labeling

    Energy Technology Data Exchange (ETDEWEB)

    Amartey, John K., E-mail: amarjk48@hotmail.co [Cyclotron and Radiopharmaceuticals Department, P.O. Box 3354, Riyadh 11211 (Saudi Arabia); Parhar, Ranjit S. [Biological and Medical Research Department, P.O. Box 3354, Riyadh 11211 (Saudi Arabia); Shi, Yufei [Genetics Department, King Faisal Specialist Hospital and Research Centre, P.O. Box 3354, Riyadh 11211 (Saudi Arabia); Al-Mohanna, Futwan [Biological and Medical Research Department, P.O. Box 3354, Riyadh 11211 (Saudi Arabia)

    2011-01-15

    A factor impeding the advancement of cell mediated therapy is the inability to track these cells in vivo by noninvasive techniques. It has been shown that cells express high levels of sulfhydryl groups. We sought to explore these groups to covalently label cells with radiolabeled maleimide derivatives. Two maleimide derivatives; N-[2-(2,5-dioxoazolinyl)ethyl](5-iodo(3-pyridyl))carboxamide and N-[2-(2,5-dioxoazolinyl)ethyl](3-iodophenyl)carboxamide ([{sup 125}I]-4 and [{sup 125}I]-8) were synthesized and radioiodinated. These compounds were evaluated for in vitro binding to neutrophils, endothelial and mesenchymal stem cells, and biodistribution of the radiolabeled stem cells in nude mice. These radiotracers were obtained in moderate to high radiochemical yields. Binding to cells were moderate (20-60%/10{sup 6} cells) and the label was retained, although washout (an average of 18-55%) was observed depending on the cell type and the tracer used. The labeled cells initially localized in well perfused organs and at a later time showed a general distribution as expected. The novel tracers labeled several cell types and shown that the stability of the label and viability of the cells were maintained in vitro and in vivo for a reasonable period and warrant further in vivo investigation.

  17. Passivation Using Molecular Halides Increases Quantum Dot Solar Cell Performance

    KAUST Repository

    Lan, Xinzheng; Voznyy, Oleksandr; Kiani, Amirreza; Garcí a de Arquer, F. Pelayo; Abbas, Abdullah Saud; Kim, Gi-Hwan; Liu, Mengxia; Yang, Zhenyu; Walters, Grant; Xu, Jixian; Yuan, Mingjian; Ning, Zhijun; Fan, Fengjia; Kanjanaboos, Pongsakorn; Kramer, Illan; Zhitomirsky, David; Lee, Philip; Perelgut, Alexander; Hoogland, Sjoerd; Sargent, Edward H.

    2015-01-01

    © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Here we report a solution-based passivation scheme is developed featuring the use of molecular iodine and PbS colloidal quantum dots (CQDs). The improved passivation translates into a longer carrier diffusion length in the solid film. This allows thicker solar-cell devices to be built while preserving efficient charge collection, leading to a certified power conversion efficiency of 9.9%, which is a new record in CQD solar cells.

  18. Passivation Using Molecular Halides Increases Quantum Dot Solar Cell Performance.

    Science.gov (United States)

    Lan, Xinzheng; Voznyy, Oleksandr; Kiani, Amirreza; García de Arquer, F Pelayo; Abbas, Abdullah Saud; Kim, Gi-Hwan; Liu, Mengxia; Yang, Zhenyu; Walters, Grant; Xu, Jixian; Yuan, Mingjian; Ning, Zhijun; Fan, Fengjia; Kanjanaboos, Pongsakorn; Kramer, Illan; Zhitomirsky, David; Lee, Philip; Perelgut, Alexander; Hoogland, Sjoerd; Sargent, Edward H

    2016-01-13

    A solution-based passivation scheme is developed featuring the use of molecular iodine and PbS colloidal quantum dots (CQDs). The improved passivation translates into a longer carrier diffusion length in the solid film. This allows thicker solar-cell devices to be built while preserving efficient charge collection, leading to a certified power conversion efficiency of 9.9%, which is a new record in CQD solar cells. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Durability and performance optimization of cathode materials for fuel cells

    Science.gov (United States)

    Colon-Mercado, Hector Rafael

    The primary objective of this dissertation is to develop an accelerated durability test (ADT) for the evaluation of cathode materials for fuel cells. The work has been divided in two main categories, namely high temperature fuel cells with emphasis on the Molten Carbonate Fuel Cell (MCFC) cathode current collector corrosion problems and low temperature fuel cells in particular Polymer Electrolyte Fuel Cell (PEMFC) cathode catalyst corrosion. The high operating temperature of MCFC has given it benefits over other fuel cells. These include higher efficiencies (>50%), faster electrode kinetics, etc. At 650°C, the theoretical open circuit voltage is established, providing low electrode overpotentials without requiring any noble metal catalysts and permitting high electrochemical efficiency. The waste heat is generated at sufficiently high temperatures to make it useful as a co-product. However, in order to commercialize the MCFC, a lifetime of 40,000 hours of operation must be achieved. The major limiting factor in the MCFC is the corrosion of cathode materials, which include cathode electrode and cathode current collector. In the first part of this dissertation the corrosion characteristics of bare, heat-treated and cobalt coated titanium alloys were studied using an ADT and compared with that of state of the art current collector material, SS 316. PEMFCs are the best choice for a wide range of portable, stationary and automotive applications because of their high power density and relatively low-temperature operation. However, a major impediment in the commercialization of the fuel cell technology is the cost involved due to the large amount of platinum electrocatalyst used in the cathode catalyst. In an effort to increase the power and decrease the cathode cost in polymer electrolyte fuel cell (PEMFC) systems, Pt-alloy catalysts were developed to increase its activity and stability. Extensive research has been conducted in the area of new alloy development and

  20. Passivation Using Molecular Halides Increases Quantum Dot Solar Cell Performance

    KAUST Repository

    Lan, Xinzheng

    2015-11-18

    © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Here we report a solution-based passivation scheme is developed featuring the use of molecular iodine and PbS colloidal quantum dots (CQDs). The improved passivation translates into a longer carrier diffusion length in the solid film. This allows thicker solar-cell devices to be built while preserving efficient charge collection, leading to a certified power conversion efficiency of 9.9%, which is a new record in CQD solar cells.

  1. A Performance Evaluation for IT/IS Implementation in Organisation: Preliminary New IT/IS Capability Evaluation (NICE Model

    Directory of Open Access Journals (Sweden)

    Hafez Salleh

    2011-12-01

    Full Text Available Most of the traditional IT/IS performance measures are based on productivity and process, which mainly focus on method of investment appraisal. There is a need to produce alternative holistic measurement models that enable soft and hard issues to be measured qualitatively. A New IT/IS Capability Evaluation (NICE framework has been designed to measure the capability of organisations to'successfully implement IT systems' and it is applicable across industries.The idea is to provide managers with measurement tools to enable them to identify where improvements are required within their organisations and to indicate their readiness prior to IT investment. The NICE framework investigates four organisational key elements: IT, Environment, Process and People, and is composed of six progressive stages of maturity that a company can achieve its IT/IS capabilities. For each maturity stage, the NICE framework describes a set of critical success factors that must be in place for the company to achieve each stage.

  2. Development and performance of a new prosthesis system using ultrasonic sensor for wrist movements: a preliminary study

    Science.gov (United States)

    2014-01-01

    Background The design and performance of a new development prosthesis system known as biomechatronics wrist prosthesis is presented in this paper. The prosthesis system was implemented by replacing the Bowden tension cable of body powered prosthesis system using two ultrasonic sensors, two servo motors and microcontroller inside the prosthesis hand for transradial user. Methods The system components and hand prototypes involve the anthropometry, CAD design and prototyping, biomechatronics engineering together with the prosthetics. The modeler construction of the system develop allows the ultrasonic sensors that are placed on the shoulder to generate the wrist movement of the prosthesis. The kinematics of wrist movement, which are the pronation/supination and flexion/extension were tested using the motion analysis and general motion of human hand were compared. The study also evaluated the require degree of detection for the input of the ultrasonic sensor to generate the wrist movements. Results The values collected by the vicon motion analysis for biomechatronics prosthesis system were reliable to do the common tasks in daily life. The degree of the head needed to bend to give the full input wave was about 45° - 55° of rotation or about 14 cm – 16 cm. The biomechatronics wrist prosthesis gave higher degree of rotation to do the daily tasks but did not achieve the maximum degree of rotation. Conclusion The new development of using sensor and actuator in generating the wrist movements will be interesting for used list in medicine, robotics technology, rehabilitations, prosthetics and orthotics. PMID:24755242

  3. Current Status of the Transmutation Reactor Technology and Preliminary Evaluation of Transmutation Performance of the KALIMER Core

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Ser Gi; Sim, Yoon Sub; Kim, Yeong Il; Kim, Young Gyum; Lee, Byung Woon; Song, Hoon; Lee, Ki Bog; Jang, Jin Wook; Lee, Dong Uk

    2005-08-15

    devised. It has been considered that the degradations of core performances resulting from increase of the transmutation rate are very important problems. From the analysis results of the state-of-art of the nuclear transmutation technology, the following technical research topics are determined as the technical solution ways for the future development and enhancement of the transmutation technology; 1) the improvement of core safety through the reduction of the coolant void reactivity worth by using the void duct assembly, 2) the design of a reference transmutation reactor for the future transmutation research through the change of the KALIMER-600 reactor core into the transmutation reactor and its core performance analysis, 3) the optimization study of the hybrid loading of uranium-free fuel and uranium fuel to improve the transmutation rate and the core safety parameters. Finally, the feasibility of the transmutation core suggested above where the void duct assemblies are devised to improve the sodium void reactivity worth and to achieve the power flattening under a single fuel enrichment and a single type of fuel assembly is analyzed and assessed. The results show that this core has its sodium coolant void reactivity less than 3$ and this core can transmutate the TRU nuclides discharged from two LWRs of the same thermal power.

  4. Analytical Evaluation of Preliminary Drop Tests Performed to Develop a Robust Design for the Standardized DOE Spent Nuclear Fuel Canister

    International Nuclear Information System (INIS)

    Ware, A.G.; Morton, D.K.; Smith, N.L.; Snow, S.D.; Rahl, T.E.

    1999-01-01

    The Department of Energy (DOE) has developed a design concept for a set of standard canisters for the handling, interim storage, transportation, and disposal in the national repository, of DOE spent nuclear fuel (SNF). The standardized DOE SNF canister has to be capable of handling virtually all of the DOE SNF in a variety of potential storage and transportation systems. It must also be acceptable to the repository, based on current and anticipated future requirements. This expected usage mandates a robust design. The canister design has four unique geometries, with lengths of approximately 10 feet or 15 feet, and an outside nominal diameter of 18 inches or 24 inches. The canister has been developed to withstand a drop from 30 feet onto a rigid (flat) surface, sustaining only minor damage - but no rupture - to the pressure (containment) boundary. The majority of the end drop-induced damage is confined to the skirt and lifting/stiffening ring components, which can be removed if de sired after an accidental drop. A canister, with its skirt and stiffening ring removed after an accidental drop, can continue to be used in service with appropriate operational steps being taken. Features of the design concept have been proven through drop testing and finite element analyses of smaller test specimens. Finite element analyses also validated the canister design for drops onto a rigid (flat) surface for a variety of canister orientations at impact, from vertical to 45 degrees off vertical. Actual 30-foot drop testing has also been performed to verify the final design, though limited to just two full-scale test canister drops. In each case, the analytical models accurately predicted the canister response

  5. Physical injury assessment of male versus female chiropractic students when learning and performing various adjustive techniques: a preliminary investigative study

    Directory of Open Access Journals (Sweden)

    Huber Laura L

    2006-08-01

    Full Text Available Abstract Background Reports of musculoskeletal injuries that some chiropractic students experienced while in the role of adjustor became increasingly evident and developed into the basis of this study. The main objective of this study was to survey a select student population and identify, by gender, the specific types of musculoskeletal injuries they experienced when learning adjustive techniques in the classroom, and performing them in the clinical setting. Methods A survey was developed to record musculoskeletal injuries that students reported to have sustained while practicing chiropractic adjustment set-ups and while delivering adjustments. The survey was modeled from similar instruments used in the university's clinic as well as those used in professional practice. Stratified sampling was used to obtain participants for the study. Data reported the anatomical areas of injury, adjustive technique utilized, the type of injury received, and the recovery time from sustained injuries. The survey also inquired as to the type and area of any past physical injuries as well as the mechanism(s of injury. Results Data obtained from the study identified injuries of the shoulder, wrist, elbow, neck, low back, and mid-back. The low back was the most common injury site reported by females, and the neck was the most common site reported by males. The reported wrist injuries in both genders were 1% male complaints and 17% female complaints. A total of 13% of female respondents reported shoulder injuries, whereas less than 1% of male respondents indicated similar complaints. Conclusion The data collected from the project indicated that obtaining further information on the subject would be worthwhile, and could provide an integral step toward developing methods of behavior modification in an attempt to reduce and/or prevent the incidence of musculoskeletal injuries.

  6. Using Audience Response Technology to provide formative feedback on pharmacology performance for non-medical prescribing students - a preliminary evaluation

    Science.gov (United States)

    2012-01-01

    Background The use of anonymous audience response technology (ART) to actively engage students in classroom learning has been evaluated positively across multiple settings. To date, however, there has been no empirical evaluation of the use of individualised ART handsets and formative feedback of ART scores. The present study investigates student perceptions of such a system and the relationship between formative feedback results and exam performance. Methods Four successive cohorts of Non-Medical Prescribing students (n=107) had access to the individualised ART system and three of these groups (n=72) completed a questionnaire about their perceptions of using ART. Semi-structured interviews were carried out with a purposive sample of seven students who achieved a range of scores on the formative feedback. Using data from all four cohorts of students, the relationship between mean ART scores and summative pharmacology exam score was examined using a non-parametric correlation. Results Questionnaire and interview data suggested that the use of ART enhanced the classroom environment, motivated students and promoted learning. Questionnaire data demonstrated that students found the formative feedback helpful for identifying their learning needs (95.6%), guiding their independent study (86.8%), and as a revision tool (88.3%). Interviewees particularly valued the objectivity of the individualised feedback which helped them to self-manage their learning. Interviewees’ initial anxiety about revealing their level of pharmacology knowledge to the lecturer and to themselves reduced over time as students focused on the learning benefits associated with the feedback. A significant positive correlation was found between students’ formative feedback scores and their summative pharmacology exam scores (Spearman’s rho = 0.71, N=107, pstudents rated the helpfulness of the individualised handsets and personalised formative feedback highly. The significant correlation between ART

  7. Analysis of A549 cell proteome alteration in response to recombinant influenza A virus nucleoprotein and its interaction with cellular proteins, a preliminary study.

    Science.gov (United States)

    Kumar, D; Tiwari, K; Rajala, M S

    Influenza A virus undergoes frequent changes of antigenicity and contributes to seasonal epidemics or unpredictable pandemics. Nucleoprotein, encoded by gene segment 5, is an internal protein of the virus and is conserved among strains of different host origins. In the current study, we analyzed the differentially expressed proteins in A549 cells transiently transfected with the recombinant nucleoprotein of influenza A virus by 2D gel electrophoresis. The resolved protein spots on gel were identified by MALDI-TOF/Mass spectrometry analysis. The majority of the host proteins detected to be differentially abundant in recombinant nucleoprotein-expressing cells as compared to vector-transfected cells are the proteins of metabolic pathways, glycolytic enzymes, molecular chaperones and cytoskeletal proteins. We further demonstrated the interaction of virus nucleoprotein with some of the identified host cellular proteins. In vitro binding assay carried out using the purified recombinant nucleoprotein (pET29a+NP-His) and A549 cell lysate confirmed the interaction between nucleoprotein and host proteins, such as alpha enolase 1, pyruvate kinase and β-actin. The preliminary data of our study provides the information on virus nucleoprotein interaction with proteins involved in glycolysis. However, studies are ongoing to understand the significance of these interactions in modulating the host factors during virus replication.

  8. Transcriptome analysis of Spodoptera frugiperda Sf9 cells reveals putative apoptosis-related genes and a preliminary apoptosis mechanism induced by azadirachtin.

    Science.gov (United States)

    Shu, Benshui; Zhang, Jingjing; Sethuraman, Veeran; Cui, Gaofeng; Yi, Xin; Zhong, Guohua

    2017-10-16

    As an important botanical pesticide, azadirachtin demonstrates broad insecticidal activity against many agricultural pests. The results of a previous study indicated the toxicity and apoptosis induction of azadirachtin in Spodoptera frugiperda Sf9 cells. However, the lack of genomic data has hindered a deeper investigation of apoptosis in Sf9 cells at a molecular level. In the present study, the complete transcriptome data for Sf9 cell line was accomplished using Illumina sequencing technology, and 97 putative apoptosis-related genes were identified through BLAST and KEGG orthologue annotations. Fragments of potential candidate apoptosis-related genes were cloned, and the mRNA expression patterns of ten identified genes regulated by azadirachtin were examined using qRT-PCR. Furthermore, Western blot analysis showed that six putative apoptosis-related proteins were upregulated after being treated with azadirachtin while the protein Bcl-2 were downregulated. These data suggested that both intrinsic and extrinsic apoptotic signal pathways comprising the identified potential apoptosis-related genes were potentially active in S. frugiperda. In addition, the preliminary results revealed that caspase-dependent or caspase-independent apoptotic pathways could function in azadirachtin-induced apoptosis in Sf9 cells.

  9. Impurities in silicon and their impact on solar cell performance

    NARCIS (Netherlands)

    Coletti, Gianluca

    2011-01-01

    Photovoltaic conversion of solar energy is a rapidly growing technology. More than 80% of global solar cell production is currently based on silicon. The aim of this thesis is to understand the complex relation between impurity content of silicon starting material (“feedstock”) and the resulting

  10. Ultimate performance of polymer: Fullerene bulk heterojunction tandem solar cells

    NARCIS (Netherlands)

    Kotlarski, J.D.; Blom, P.W.M.

    2011-01-01

    We present the model calculations to explore the potential of polymer:fullerene tandem solar cells. As an approach we use a combined optical and electrical device model, where the absorption profiles are used as starting point for the numerical current-voltage calculations. With this model a maximum

  11. Transparent high-performance CDSE thin-film solar cells

    International Nuclear Information System (INIS)

    Mahawela, P.; Jeedigunta, S.; Vakkalanka, S.; Ferekides, C.S.; Morel, D.L.

    2005-01-01

    Simulations indicate that 25-30% efficiency can be achieved with a four-terminal thin-film tandem structure. The bottom low band gap cell can be CuIn 1-x Ga x Se 2 , and CdSe is proposed as the top cell, as it has an ideal band gap of 1.7 eV. In addition to the efficiency requirements, the top cell must also be transparent to effectively transmit sub band gap light to the bottom cell. We have developed CdSe devices that meet many of the requirements of this tandem structure. High electronic quality CdSe has been deposited on SnO 2 and ZnO, which serve as the transparent n-type contact. The p-type transparent contact is ZnSe/Cu. Voc's of 475 mV have been achieved and can be further improved with better contacts. However, record Jsc's in excess of 17 mA/cm 2 have been achieved. This is close to the target 18 mA/cm 2 to meet the efficiency objectives. Transmission of 80% of the sub band gap radiation has been demonstrated for 2-no. muno. m-thick absorber layers. This is also close to the 85% target to achieve the overall tandem efficiency objectives. Improvement of the contact layers to achieve the Voc target is the final challenge

  12. Wireless data performance in multi-cell scenarios

    NARCIS (Netherlands)

    Bonald, T.; Borst, S.C.; Hegde, N.; Proutière, A.

    2004-01-01

    The performance of wireless data systems has been extensively studied in the context of a single base station. In the present paper we investigate the flow-level performance in networks with multiple base stations. We specifically examine the complex, dynamic interaction of the number of active

  13. Crystalline silicon cell performance at low light intensities

    Energy Technology Data Exchange (ETDEWEB)

    Reich, N.H.; van Sark, W.G.J.H.M.; Alsema, E.A.; Turkenburg, W.C. [Utrecht University, Faculty of Science, Copernicus Institute for Sustainable Development and Innovation, Department of Science, Techonology and Society, Heidelberglaan 2, 3584 CS Utrecht (Netherlands); Lof, R.W.; Schropp, R.E.I. [Utrecht University, Faculty of Science, Debye Institute for Nanomaterials Science, Nanophotonics - Physics of Device, Utrecht University, P.O. Box 80.000, 3508 TA Utrecht (Netherlands); Sinke, W.C. [Energy research Centre of the Netherlands (ECN), P.O. Box 1, 1755 ZG Petten (Netherlands)

    2009-09-15

    Measured and modelled JV characteristics of crystalline silicon cells below one sun intensity have been investigated. First, the JV characteristics were measured between 3 and 1000 W/m{sup 2} at 6 light levels for 41 industrially produced mono- and multi-crystalline cells from 8 manufacturers, and at 29 intensity levels for a single multi-crystalline silicon between 0.01 and 1000 W/m{sup 2}. Based on this experimental data, the accuracy of the following four modelling approaches was evaluated: (1) empirical fill factor expressions, (2) a purely empirical function, (3) the one-diode model and (4) the two-diode model. Results show that the fill factor expressions and the empirical function fail at low light intensities, but a new empirical equation that gives accurate fits could be derived. The accuracy of both diode models are very high. However, the accuracy depends considerably on the used diode model parameter sets. While comparing different methods to determine diode model parameter sets, the two-diode model is found to be preferred in principle: particularly its capability in accurately modelling V{sub OC} and efficiency with one and the same parameter set makes the two-diode model superior. The simulated energy yields of the 41 commercial cells as a function of irradiance intensity suggest unbiased shunt resistances larger than about 10 k{omega} cm{sup 2} may help to avoid low energy yields of cells used under predominantly low light intensities. Such cells with diode currents not larger than about 10{sup -9} A/cm{sup 2} are excellent candidates for Product Integrated PV (PIPV) appliances. (author)

  14. The Comparative Performance of Batteries: The Lead-Acid and the Aluminum-Air Cells.

    Science.gov (United States)

    LeRoux, Xavier; And Others

    1996-01-01

    Describes a teaching program that shows how electrochemical principles can be conveyed by means of hands-on experiences of student-centered teaching experiments. Employs the readily available lead-acid cell and the simple aluminum-air cell. Discusses the batteries, equilibrium cell potential, performance comparison, current, electrode separation,…

  15. Preliminary Studies of the Performance of Quinoa (Chenopodium quinoa Willd.) Genotypes under Irrigated and Rainfed Conditions of Central Malawi.

    Science.gov (United States)

    Maliro, Moses F A; Guwela, Veronica F; Nyaika, Jacinta; Murphy, Kevin M

    2017-01-01

    The goal of sustainable intensification of agriculture in Malawi has led to the evaluation of innovative, regionally novel or under-utilized crop species. Quinoa ( Chenopodium quinoa Willd.) has the potential to provide a drought tolerant, nutritious alternative to maize. We evaluated 11 diverse varieties of quinoa for their yield and agronomic performance at two locations, Bunda and Bembeke, in Malawi. The varieties originated from Ecuador, Chile and Bolivia in South America; the United States and Canada in North America; and, Denmark in Europe, and were chosen based on their variation in morphological and agronomic traits, and their potential for adaptation to the climate of Malawi. Plant height, panicle length, days to maturity, harvest index, and seed yield were recorded for each variety under irrigation at Bunda and Bembeke, and under rainfed conditions at Bunda. Plant height was significantly influenced by both genotype and environment. There were also significant differences between the two locations for panicle length whereas genotype and genotype × environment (G × E) interaction were not significantly different. Differences were found for genotype and G × E interaction for harvest index. Notably, differences for genotype, environment and G × E were found for grain yield. Seed yield was higher at Bunda (237-3019 kg/ha) than Bembeke (62-692 kg/ha) under irrigated conditions. The highest yielding genotype at Bunda was Titicaca (3019 kg/ha) whereas Multi-Hued was the highest (692 kg/ha) at Bembeke. Strong positive correlations between seed yield and (1) plant height ( r = 0.74), (2) days to maturity ( r = 0.76), and (3) biomass ( r = 0.87) were found under irrigated conditions. The rainfed evaluations at Bunda revealed significant differences in seed yield, plant biomass, and seed size among the genotypes. The highest yielding genotype was Black Seeded (2050 kg/ha) followed by Multi-Hued (1603 kg/ha) and Bio-Bio (1446 kg/ha). Ecuadorian (257 kg/ha) was

  16. Using Audience Response Technology to provide formative feedback on pharmacology performance for non-medical prescribing students - a preliminary evaluation

    Directory of Open Access Journals (Sweden)

    Mostyn Alison

    2012-11-01

    Full Text Available Abstract Background The use of anonymous audience response technology (ART to actively engage students in classroom learning has been evaluated positively across multiple settings. To date, however, there has been no empirical evaluation of the use of individualised ART handsets and formative feedback of ART scores. The present study investigates student perceptions of such a system and the relationship between formative feedback results and exam performance. Methods Four successive cohorts of Non-Medical Prescribing students (n=107 had access to the individualised ART system and three of these groups (n=72 completed a questionnaire about their perceptions of using ART. Semi-structured interviews were carried out with a purposive sample of seven students who achieved a range of scores on the formative feedback. Using data from all four cohorts of students, the relationship between mean ART scores and summative pharmacology exam score was examined using a non-parametric correlation. Results Questionnaire and interview data suggested that the use of ART enhanced the classroom environment, motivated students and promoted learning. Questionnaire data demonstrated that students found the formative feedback helpful for identifying their learning needs (95.6%, guiding their independent study (86.8%, and as a revision tool (88.3%. Interviewees particularly valued the objectivity of the individualised feedback which helped them to self-manage their learning. Interviewees’ initial anxiety about revealing their level of pharmacology knowledge to the lecturer and to themselves reduced over time as students focused on the learning benefits associated with the feedback. A significant positive correlation was found between students’ formative feedback scores and their summative pharmacology exam scores (Spearman’s rho = 0.71, N=107, p Conclusions Despite initial anxiety about the use of individualised ART units, students rated the helpfulness of the

  17. Performance Degradation Tests of Phosphoric Acid Doped PBI Membrane Based High Temperature PEM Fuel Cells

    DEFF Research Database (Denmark)

    Zhou, Fan; Araya, Samuel Simon; Grigoras, Ionela

    2014-01-01

    Degradation tests of two phosphoric acid (PA) doped PBI membrane based HT-PEM fuel cells were reported in this paper to investigate the effects of start/stop and the presence of methanol in the fuel to the performance degradation. Continuous tests with H2 and simulated reformate which was composed...... of H2, water steam and methanol as the fuel were performed on both single cells. 12-h-startup/12-h-shutdown dynamic tests were performed on the first single cell with pure dry H2 as the fuel and on the second single cell with simulated reformate as the fuel. Along with the tests electrochemical...... techniques such as polarization curves and electrochemical impedance spectroscopy (EIS) were employed to study the degradation mechanisms of the fuel cells. Both single cells showed an increase in the performance in the H2 continuous tests, because of a decrease in the ORR kinetic resistance probably due...

  18. Performance of PEM fuel cells stack as affected by number of cell and gas flow-rate

    Science.gov (United States)

    Syampurwadi, A.; Onggo, H.; Indriyati; Yudianti, R.

    2017-03-01

    The proton exchange membrane fuel cell (PEMFC) is a promising technology as an alternative green energy due to its high power density, low operating temperatures, low local emissions, quiet operation and fast start up-shutdown. In order to apply fuel cell as portable power supply, the performance investigation of small number of cells is needed. In this study, PEMFC stacks consisting of 1, 3, 5 and 7-cells with an active area of 25 cm2 per cell have been designed and developed. Their was evaluated in variation of gas flow rate. The membrane electrode assembly (MEA) was prepared by hot-pressing commercial gas diffusion electrodes (Pt loading 0.5 mg/cm2) on pre-treated Nafion 117 membrane. The stacks were constructed using bipolar plates in serpentine pattern and Z-type gas flow configuration. The experimental results were presented as polarization and power output curves which show the effects of varying number of cells and H2/O2 flow-rates on the PEMFC performance. The experimental results showed that not only number of cells and gas flow-rates affected the fuel cells performance, but also the operating temperature as a result of electrochemistry reaction inside the cell.

  19. Direct alcohol fuel cells materials, performance, durability and applications

    CERN Document Server

    Corti, Horacio R; Antolini, Ermete

    2014-01-01

    After an introductory overview of this emerging form of clean, portable energy, experts from industry and academia discuss the challenges in materials development, performance, and commercialization standing between DAFCs and widespread public use.

  20. Method to fabricate high performance tubular solid oxide fuel cells

    Science.gov (United States)

    Chen, Fanglin; Yang, Chenghao; Jin, Chao

    2013-06-18

    In accordance with the present disclosure, a method for fabricating a solid oxide fuel cell is described. The method includes forming an asymmetric porous ceramic tube by using a phase inversion process. The method further includes forming an asymmetric porous ceramic layer on a surface of the asymmetric porous ceramic tube by using a phase inversion process. The tube is co-sintered to form a structure having a first porous layer, a second porous layer, and a dense layer positioned therebetween.

  1. Improving the performance of solid oxide fuel cell systems

    OpenAIRE

    Halinen, Matias

    2015-01-01

    Solid oxide fuel cell (SOFC) systems can provide power production at a high electrical efficiency and with very low emissions. Furthermore, they retain their high electrical efficiency over a wide range of output power and offer good fuel flexibility, which makes them well suited for a range of applications. Currently SOFC systems are under investigation by researchers as well as being developed by industrial manufacturers. The first commercial SOFC systems have been on the market for some...

  2. Preliminary performance of image quality for a low-dose C-arm CT system with a flat-panel detector

    Energy Technology Data Exchange (ETDEWEB)

    Kyung Cha, Bo [Advanced Medical Device Research Center, Korea Electrotechnology Research Institute, Ansan (Korea, Republic of); Seo, Chang-Woo [Department of Radiation Convergence Engineering, College of Health Science, Yonsei University, Wonju (Korea, Republic of); Yang, Keedong [Advanced Medical Device Research Center, Korea Electrotechnology Research Institute, Ansan (Korea, Republic of); Jeon, Seongchae, E-mail: sarim@keri.re.kr [Advanced Medical Device Research Center, Korea Electrotechnology Research Institute, Ansan (Korea, Republic of); Huh, Young [Advanced Medical Device Research Center, Korea Electrotechnology Research Institute, Ansan (Korea, Republic of)

    2015-06-01

    Digital flat panel imager (FPI)-based cone-beam computed tomography (CBCT) has been widely used in C-arm imaging for spine surgery and interventional procedures. The system provides real-time fluoroscopy with high spatial resolution and three-dimensional (3D) visualization of anatomical structure without the need for patient transportation in interventional suite. In this work, a prototype CBCT imaging platform with continuous single rotation about the gantry was developed by using a large-area flat-panel detector with amorphous Si-based thin film transistor matrix. The different 2D projection images were acquired during constant gantry velocity for reconstructed images at a tube voltage of 80–120 kVp, and different current (10–50 mA) conditions. Various scan protocols were applied to a chest phantom human by changing the number of projection images and scanning angles. The projections were then reconstructed into a volumetric data of sections by using a 3D reconstruction algorithm (e.g., filtered back projection). The preliminary quantitative X-ray performance of our CBCT system was investigated by using the American Association of Physicists in Medicine CT phantom in terms of spatial resolution, contrast resolution, and CT number linearity for mobile or fixed C-arm based CBCT application with limited rotational geometry. The novel results of the projection data with different scanning angles and angular increments in the orbital gantry platform were acquired and evaluated experimentally.

  3. Preliminary performance of image quality for a low-dose C-arm CT system with a flat-panel detector

    International Nuclear Information System (INIS)

    Kyung Cha, Bo; Seo, Chang-Woo; Yang, Keedong; Jeon, Seongchae; Huh, Young

    2015-01-01

    Digital flat panel imager (FPI)-based cone-beam computed tomography (CBCT) has been widely used in C-arm imaging for spine surgery and interventional procedures. The system provides real-time fluoroscopy with high spatial resolution and three-dimensional (3D) visualization of anatomical structure without the need for patient transportation in interventional suite. In this work, a prototype CBCT imaging platform with continuous single rotation about the gantry was developed by using a large-area flat-panel detector with amorphous Si-based thin film transistor matrix. The different 2D projection images were acquired during constant gantry velocity for reconstructed images at a tube voltage of 80–120 kVp, and different current (10–50 mA) conditions. Various scan protocols were applied to a chest phantom human by changing the number of projection images and scanning angles. The projections were then reconstructed into a volumetric data of sections by using a 3D reconstruction algorithm (e.g., filtered back projection). The preliminary quantitative X-ray performance of our CBCT system was investigated by using the American Association of Physicists in Medicine CT phantom in terms of spatial resolution, contrast resolution, and CT number linearity for mobile or fixed C-arm based CBCT application with limited rotational geometry. The novel results of the projection data with different scanning angles and angular increments in the orbital gantry platform were acquired and evaluated experimentally

  4. Preliminary temperature Accelerated Life Test (ALT) on III-V commercial concentrator triple-junction solar cells

    OpenAIRE

    Espinet González, Pilar; Algora del Valle, Carlos; Orlando Carrillo, Vincenzo; Nuñez Mendoza, Neftali; Vázquez López, Manuel; Bautista Villares, Jesus; Xiugang, He; Barrutia Poncela, Laura; Rey-Stolle Prado, Ignacio; Araki, Kenji

    2012-01-01

    A quantitative temperature accelerated life test on sixty GaInP/GaInAs/Ge triple-junction commercial concentrator solar cells is being carried out. The final objective of this experiment is to evaluate the reliability, warranty period, and failure mechanism of high concentration solar cells in a moderate period of time. The acceleration of the degradation is realized by subjecting the solar cells at temperatures markedly higher than the nominal working temperature under a concentrator Three e...

  5. A preliminary study on action mechanisms of surviving expression in cell apoptosis induced by high-LET radiation

    International Nuclear Information System (INIS)

    Jin Xiaodong; Li Qiang; Gong Li; Wu Qingfeng; Li Ping; Dai Zhongying; Liu Xinguo; Tao Jiajun

    2010-01-01

    It has been proven that over-expression of surviving in cancerous cell lines is related to the radioresistance of cells to high-LET radiation in previous work. In this study, action mechanisms of surviving gene in apoptosis induced by high-LET radiation were investigated. We found that inhibiting surviving by siRNA had no notable influence on Bcl-2 and Bax expressions induced by carbon ions. Surviving depressed cell apoptosis through the inhibition of the activities of caspase-3 and -9 possibly in cell apoptosis induced by high-LET radiation. (authors)

  6. Preliminary results on the non-thermal effects of 200-350 GHz radiation on the growth rate of S. cerevisiae cells in microcolonies

    Science.gov (United States)

    Hadjiloucas, S.; Chahal, M. S.; Bowen, J. W.

    2002-11-01

    We report preliminary results from studies of biological effects induced by non-thermal levels of non-ionizing electromagnetic radiation. Exponentially growing Saccharomyces cerevisiae yeast cells grown on dry media were exposed to electromagnetic fields in the 200-350 GHz frequency range at low power density to observe possible non-thermal effects on the microcolony growth. Exposure to the electromagnetic field was conducted over 2.5 h. The data from exposure and control experiments were grouped into either large-, medium- or small-sized microcolonies to assist in the accurate assessment of growth. The three groups showed significant differences in growth between exposed and control microcolonies. A statistically significant enhanced growth rate was observed at 341 GHz. Growth rate was assessed every 30 min via time-lapse photography. Possible interaction mechanisms are discussed, taking into account Frohlich's hypothesis.

  7. Preliminary results on the non-thermal effects of 200-350 GHz radiation on the growth rate of S. cerevisiae cells in microcolonies

    Energy Technology Data Exchange (ETDEWEB)

    Hadjiloucas, S; Chahal, M S; Bowen, J W [Department of Cybernetics, University of Reading, Whiteknights, RG6 6AY, Berkshire (United Kingdom)

    2002-11-07

    We report preliminary results from studies of biological effects induced by non-thermal levels of non-ionizing electromagnetic radiation. Exponentially growing Saccharomyces cerevisiae yeast cells grown on dry media were exposed to electromagnetic fields in the 200-350 GHz frequency range at low power density to observe possible non-thermal effects on the microcolony growth. Exposure to the electromagnetic field was conducted over 2.5 h. The data from exposure and control experiments were grouped into either large-, medium- or small-sized microcolonies to assist in the accurate assessment of growth. The three groups showed significant differences in growth between exposed and control microcolonies. A statistically significant enhanced growth rate was observed at 341 GHz. Growth rate was assessed every 30 min via time-lapse photography. Possible interaction mechanisms are discussed, taking into account Frohlich's hypothesis.

  8. No detection of Merkel cell polyomavirus in oral lichen planus: Results of a preliminary study in a French cohort of patients.

    Science.gov (United States)

    Masson Regnault, Marie; Vigarios, Emmanuelle; Projetti, Fabrice; Herbault-Barres, Beatrice; Tournier, Emilie; Lamant, Laurence; Sibaud, Vincent

    2017-11-01

    Oral lichen planus (OLP) is a chronic inflammatory disease considered as a CD8+ T lymphocyte-mediated autoimmune reaction, which may be triggered by undetermined virus. Recent reports have described the detection of Merkel cell polyomavirus (MCPyV) DNA in oral samples from healthy patients and in patients with different forms of oral cancers. We therefore investigated in a prospective way whether MCPyV was detectable in oral lesions of patients with active OLP. Our preliminary results do not support the hypothesis that OLP may be triggered by MCPyV infection. Further studies are needed to evaluate the involvement of other human polyomaviruses in OLP pathogenesis. © 2017 Wiley Periodicals, Inc.

  9. Study on the micro direct ethanol fuel cell (Micro-DEFC) performance

    Science.gov (United States)

    Saisirirat, Penyarat; Joommanee, Bordindech

    2018-01-01

    The direct ethanol fuel cell (DEFC) is selected for this research. DEFC uses ethanol in the fuel cell instead of the more toxic methanol. Ethanol is more attractive than methanol by many reasons. Ethanol is a hydrogen-rich liquid and it has a higher specific energy (8.0 kWh/kg) compared to that of methanol (6.1 kWh/kg). Ethanol can be obtained in great quantity from biomass through a fermentation process from renewable resources such as sugar cane, wheat, corn, and even straw. The use of ethanol would also overcome both the storage and infrastructure challenge of hydrogen for fuel cell applications. The experimental apparatus on the micro direct ethanol fuel cell for measuring the cell performance has been set for this research. The objective is to study the micro direct ethanol fuel cell performance for applying with the portable electronic devices. The cell performance is specified in the terms of cell voltage, cell current and power of the cell at room operating temperature and 1 atm for the pressure and also includes the ethanol fuel consumption. The effect of operating temperature change on the electrical production performance is also studied. The steady-state time for collecting each data value is about 5-10 minutes. The results show that with the increase of concentrations of ethanol by volume, the reactant concentration at the reaction sites increases so the electrochemical rate also increases but when it reaches the saturated point the performance gradually drops.

  10. Long Term Performance Study of a Direct Methanol Fuel Cell Fed with Alcohol Blends

    OpenAIRE

    Teresa J. Leo; Miguel A. Raso; Emilio Navarro; Eleuterio Mora

    2013-01-01

    The use of alcohol blends in direct alcohol fuel cells may be a more environmentally friendly and less toxic alternative to the use of methanol alone in direct methanol fuel cells. This paper assesses the behaviour of a direct methanol fuel cell fed with aqueous methanol, aqueous ethanol and aqueous methanol/ethanol blends in a long term experimental study followed by modelling of polarization curves. Fuel cell performance is seen to decrease as the ethanol content rises, and subsequent opera...

  11. High performance hybrid silicon micropillar solar cell based on light trapping characteristics of Cu nanoparticles

    Directory of Open Access Journals (Sweden)

    Yulong Zhang

    2018-05-01

    Full Text Available High performance silicon combined structure (micropillar with Cu nanoparticles solar cell has been synthesized from N-type silicon substrates based on the micropillar array. The combined structure solar cell exhibited higher short circuit current rather than the silicon miropillar solar cell, which the parameters of micropillar array are the same. Due to the Cu nanoparticles were decorated on the surface of silicon micropillar array, the photovoltaic properties of cells have been improved. In addition, the optimal efficiency of 11.5% was measured for the combined structure solar cell, which is better than the silicon micropillar cell.

  12. High performance hybrid silicon micropillar solar cell based on light trapping characteristics of Cu nanoparticles

    Science.gov (United States)

    Zhang, Yulong; Fan, Zhiqiang; Zhang, Weijia; Ma, Qiang; Jiang, Zhaoyi; Ma, Denghao

    2018-05-01

    High performance silicon combined structure (micropillar with Cu nanoparticles) solar cell has been synthesized from N-type silicon substrates based on the micropillar array. The combined structure solar cell exhibited higher short circuit current rather than the silicon miropillar solar cell, which the parameters of micropillar array are the same. Due to the Cu nanoparticles were decorated on the surface of silicon micropillar array, the photovoltaic properties of cells have been improved. In addition, the optimal efficiency of 11.5% was measured for the combined structure solar cell, which is better than the silicon micropillar cell.

  13. Autologous cell therapy as a new approach to treatment of radiation-induced bone marrow aplasia: preliminary study in a baboon model

    Energy Technology Data Exchange (ETDEWEB)

    Herodin, F.; Drouet, M. [Radiohematology Unit, Centre de Recherches du Service de Sante des Armees, La Tronche CEDEX (France)

    2002-07-01

    The sparing of viable hematopoietic stem and progenitor cells located in underexposed bone marrow territories associated with the relative radioresistance of certain stem cell populations is the rationale for autologous cell therapy consisting of ex vivo expansion of residual cells after collection postirradiation. The feasibility of this treatment mainly depends on time constraints and hematopoietic cell threshold. We showed in this study that in the absence of early-acting mobilizing agent administration, subliminar amounts of CD34{sup +} cells can be collected (1 x 10{sup 6} CD34{sup +} cells/100 mL bone marrow or for 1 L apheresis) from 6-Gy {gamma} globally irradiated baboons. Residual CD34{sup +} cells were successfully expanded in serum-free medium in the presence of antiapoptotic cytokine combination (stem cell factor + FLT-3 ligand + thrombopoietin + interleukin 3, 50 ng/mL each, i.e., 4F): K{sub CD34{sup +}} = x2.8 and x13.7 (n=2). Moreover, we demonstrated the short-term neutrophil engraftment potential of a low-size mixed expanded graft (1.5 x 10{sup 6} final CD34{sup +}cells/kg) issued from the coculture of unirradiated (20%) and 2.5-Gy in vitro irradiated (80%) CD34{sup +} cells on an allogeneic stromal cell layer in the presence of 4F. Further preclinical research needs to be performed to clearly establish this therapeutic approach that could be optimized by the early administration of antiapoptotic cytokines. (author)

  14. Theoretical performance of hydrogen-bromine rechargeable SPE fuel cell. [Solid Polymer Electrolyte

    Science.gov (United States)

    Savinell, R. F.; Fritts, S. D.

    1988-01-01

    A mathematical model was formulated to describe the performance of a hydrogen-bromine fuel cell. Porous electrode theory was applied to the carbon felt flow-by electrode and was coupled to theory describing the solid polymer electrolyte (SPE) system. Parametric studies using the numerical solution to this model were performed to determine the effect of kinetic, mass transfer, and design parameters on the performance of the fuel cell. The results indicate that the cell performance is most sensitive to the transport properties of the SPE membrane. The model was also shown to be a useful tool for scale-up studies.

  15. Performance of Platinum Nanoparticles / Multiwalled Carbon Nanotubes / Bacterial Cellulose Composite as Anode Catalyst for Proton Exchange Membrane Fuel Cells

    Directory of Open Access Journals (Sweden)

    Henry Fonda Aritonang

    2017-05-01

    Full Text Available Highly dispersed platinum (Pt nanoparticles / multiwalled carbon nanotubes (MWCNTs on bacterial cellulose (BC as anode catalysts for proton exchange membrane fuel cells (PEMFC were prepared with various precursors and their electro-catalytic activities towards hydrogen oxidation at 70 oC under non-humidified conditions. The composite was prepared by deposition of Pt nanoparticles and MWCNTs on BC gel by impregnation method using a water solution of metal precursors and MWCNTs followed by reducing reaction using a hydrogen gas. The composite was characterized by using TEM (transmission electron microscopy, EDS (energy dispersive spectroscopy, and XRD (X-ray diffractometry techniques. TEM images and XRD patterns both lead to the observation of spherical metallic Pt nanoparticles with mean diameter of 3-11 nm well impregnated into the BC fibrils. Preliminary tests on a single cell indicate that renewable BC is a good prospect to be explored as a membrane in fuel cell field. Copyright © 2017 BCREC Group. All rights reserved Received: 21st November 2016; Revised: 26th February 2017; Accepted: 27th February 2017 How to Cite: Aritonang, H.F., Kamu, V.S., Ciptati, C., Onggo, D., Radiman, C.L. (2017. Performance of Platinum Nanoparticles / Multiwalled Carbon Nanotubes / Bacterial Cellulose Composite as Anode Catalyst for Proton Exchange Membrane Fuel Cells. Bulletin of Chemical Reaction Engineering & Catalysis, 12 (2: 287-292 (doi:10.9767/bcrec.12.2.803.287-292 Permalink/DOI: http://dx.doi.org/10.9767/bcrec.12.2.803.287-292

  16. Preliminary study of the role of gastrointestinal endocrine cells in the maintenance of villous structure following X-irradiation

    International Nuclear Information System (INIS)

    Wyatt, M.G.; Hume, S.P.; Carr, K.E.; Marigold, J.C.

    1987-01-01

    The mechanism of gastrointestinal villous damage following ionizing irradiation is complex. Various compartments within the gastrointestinal tract have in turn been considered important for the maintenance of normal villous structure. To date, however, evidence for a single overriding regulator of epithelial well-being is lacking. In this study, the role of the gastro-intestinal (enteroendocrine) cells is explored and comparison made between endocrine cell number and villous structure. Experiments were organized using both control and irradiated groups of mice. Two time points (1 and 3 days) and three radiation doses (6, 10 and 18Gy) were employed. A simple method for endocrine cell identification and subsequent quantification is described. Endocrine cell number was then compared with villous surface detail, as seen with a scanning electron microscope (SEM). Results indicated a decrease in the endocrine cell number at all three radiation doses. Whereas at low doses endocrine cell recovery occurred between 1 and 3 days, at medium and high doses further decline was noticed. A similar pattern was seen when considering villous surface structure. It is suggested that both scanning electron microscopy and endocrine cell number provide a more sensitive indicator of gastrointestinal radiation damage than do current crypt counting techniques. In addition, a link between endocrine cell number and villous structure is proposed

  17. Preliminary experience on the use of the Adnatest® system for detection of circulating tumor cells in prostate cancer patients.

    Science.gov (United States)

    Todenhöfer, Tilman; Hennenlotter, Jörg; Feyerabend, Susan; Aufderklamm, Stefan; Mischinger, Johannes; Kühs, Ursula; Gerber, Valentina; Fetisch, Jasmin; Schilling, David; Hauch, Siegfried; Stenzl, Arnulf; Schwentner, Christian

    2012-08-01

    The Adnatest® system combines immunomagnetic enrichment of epithelial cells with polymerase chain reaction for prostate cancer (PC)-specific transcripts for the detection circulating tumor cells (CTCs). We evaluated the Adnatest® in patients with castration-resistant PC receiving docetaxel chemotherapy. CTCs were assessed in 16 patients with castration-resistant PC before cycles one and three of chemotherapy. Furthermore, markers of stem cells and epithelial-mesenchymal transition were assessed. Treatment response was assessed by imaging and prostate-specific antigen measurements. Before chemotherapy, 11 patients were Adnatest®-positive whereas five patients were Adnatest®-positive before cycle three. A positive Adnatest® correlated with radiological progression (p=0.02). Rates of disease progression in epidermal growth factor receptor (EGFR)-positive and -negative patients were 100% and 7.7% (p=0.03). In this preliminary study, the Adnatest® detected CTCs in a considerable proportion of patients with castration-resistant PC. First data on certain markers (EGFR and aldehyd dehydrogenase 1) encourage future studies investigating transcripts predicting treatment response.

  18. Nanocrystalline dye-sensitized solar cells having maximum performance

    Energy Technology Data Exchange (ETDEWEB)

    Kroon, M.; Bakker, N.J.; Smit, H.J.P. [ECN Solar Energy, Petten (Netherlands); Liska, P.; Thampi, K.R.; Wang, P.; Zakeeruddin, S.M.; Graetzel, M. [LPI-ISIC, Ecole Polytechnique Federale de Lausanne EPFL, Station 6, CH-1015 Lausanne (Switzerland); Hinsch, A. [Fraunhofer Institute for Solar Energy Systems ISE, Heidenhofstr.2, D-79110 Freiburg (Germany); Hore, S.; Wuerfel, U.; Sastrawan, R. [Freiburg Materials Research Centre FMF, Stefan-Meier Str. 21, 79104 Freiburg (Germany); Durrant, J.R.; Palomares, E. [Centre for Electronic Materials and Devices, Department of Chemistry, Imperial College London, Exhibition road SW7 2AY (United Kingdom); Pettersson, H.; Gruszecki, T. [IVF Industrial Research and Development Corporation, Argongatan 30, SE-431 53 Moelndal (Sweden); Walter, J.; Skupien, K. [Cracow University of Technology CUTECH, Jana Pawla II 37, 31-864 Cracow (Poland); Tulloch, G.E. [Greatcell Solar SA GSA, Ave Henry-Warnery 4, 1006 Lausanne (Switzerland)

    2007-01-15

    This paper presents an overview of the research carried out by a European consortium with the aim to develop and test new and improved ways to realise dye-sensitized solar cells (DSC) with enhanced efficiencies and stabilities. Several new areas have been explored in the field of new concepts and materials, fabrication protocols for TiO2 and scatterlayers, metal oxide blocking layers, strategies for co-sensitization and low temperature processes of platinum deposition. Fundamental understanding of the working principles has been gained by means of electrical and optical modelling and advanced characterization techniques. Cost analyses have been made to demonstrate the potential of DSC as a low cost thin film PV technology. The combined efforts have led to maximum non-certified power conversion efficiencies under full sunlight of 11% for areas <0c2 cm{sup 2} and 10c1% for a cell with an active area of 1c3 cm{sup 2}. Lifetime studies revealed negligible device degradation after 1000 hrs of accelerated tests under thermal stress at 80C in the dark and visible light soaking at 60C. An outlook summarizing future directions in the research and large-scale production of DSC is presented.

  19. Magnetic field enhancement of organic photovoltaic cells performance.

    Science.gov (United States)

    Oviedo-Casado, S; Urbina, A; Prior, J

    2017-06-27

    Charge separation is a critical process for achieving high efficiencies in organic photovoltaic cells. The initial tightly bound excitonic electron-hole pair has to dissociate fast enough in order to avoid photocurrent generation and thus power conversion efficiency loss via geminate recombination. Such process takes place assisted by transitional states that lie between the initial exciton and the free charge state. Due to spin conservation rules these intermediate charge transfer states typically have singlet character. Here we propose a donor-acceptor model for a generic organic photovoltaic cell in which the process of charge separation is modulated by a magnetic field which tunes the energy levels. The impact of a magnetic field is to intensify the generation of charge transfer states with triplet character via inter-system crossing. As the ground state of the system has singlet character, triplet states are recombination-protected, thus leading to a higher probability of successful charge separation. Using the open quantum systems formalism we demonstrate that the population of triplet charge transfer states grows in the presence of a magnetic field, and discuss the impact on carrier population and hence photocurrent, highlighting its potential as a tool for research on charge transfer kinetics in this complex systems.

  20. Modelling the Performance of Product Integrated Photovoltaic (PIPV) Cells Indoors

    NARCIS (Netherlands)

    Apostolou, G.; Verwaal, M.; Reinders, Angelina H.M.E.

    2014-01-01

    In this paper we present a model, which have been developed for the estimation of the PV products’ cells’ performance in an indoor environment. The model computes the efficiency and power production of PV technologies, as a function of distance from natural and artificial light sources. It intents

  1. Effect of time-varying humidity on the performance of a polymer electrolyte membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Noorani, Shamsuddin [Department of Mechanical Engineering, University of Michigan-Dearborn (United States); Shamim, Tariq [Mechanical Engineering, Masdar Institute of Science and Technology (United Arab Emirates)], E-mail: tshamim@masdar.ac.ae

    2011-07-01

    In the energy sector, fuel cells constitute a promising solution for the future due to their energy-efficient and environment-friendly characteristics. However, the performance of fuel cells is very much affected by the humidification level of the reactants, particularly in hot regions. The aim of this paper is to develop a better understanding of the effect of driving conditions on the performance of fuel cells. A macroscopic single-fuel-cell-based, one dimensional, isothermal model was used on a polymer electrolyte membrane fuel cell to carry out a computational study of the impact of humidity conditions which vary over time. It was found that the variation of humidity has a significant effect on water distribution but a much lower impact on power and current densities. This paper provided useful information on fuel cells' performance under varying conditions which could be used to improve their design for mobile applications.

  2. Impact of temperature on performance of series and parallel connected mono-crystalline silicon solar cells

    Directory of Open Access Journals (Sweden)

    Subhash Chander

    2015-11-01

    Full Text Available This paper presents a study on impact of temperature on the performance of series and parallel connected mono-crystalline silicon (mono-Si solar cell employing solar simulator. The experiment was carried out at constant light intensity 550 W/m2with cell temperature in the range 25–60 oC for single, series and parallel connected mono-Si solar cells. The performance parameters like open circuit voltage, maximum power, fill factor and efficiency are found to decrease with cell temperature while the short circuit current is observed to increase. The experimental results reveal that silicon solar cells connected in series and parallel combinations follow the Kirchhoff’s laws and the temperature has a significant effect on the performance parameters of solar cell.

  3. Preliminary study of cell metabolism, by use of NBT test, determination the intensity of lipid peroxidation and antioxidant activity

    Directory of Open Access Journals (Sweden)

    Diana BEI

    2009-05-01

    Full Text Available Otto Warburg, in the early part of the 20th century, originated a hypothesis, that the cause of cancer is primarily a defect in energy metabolism.A decrease in the capacity of mitochondria to reduce NAD(P, together with a decline in the NAD(PH/NAD(P redox couple, uncouples oxidative phosphorylation, lead to depletion of ATP and decrease the cell viability.Nitro-bleu tetrazolium have been used to assay cell proliferation and viability. The method to measure cell proliferation is based on enzymatic cleavage of the tetrazolium salts to a water-soluble formazan dye.Succinate-tetrazolium reductase, is an enzymatic sistem, which belongs to the respiratory chain of the mitochondria and it is active only in viable cells. The reagent diffuses into the cells and it is cleaved to formazan. The absorption change is measured and analysed.Free radicals such as superoxide, can cause a damage in cellular components, but several antioxidants inhibiting the lipid peroxidation and limiting the level of free radicals in cells.In the present study we had in view the proliferation and viability of leukemia cells during antineoplastic treatment along with the alteration of the serum level of malondialdehyde (MDA and ceruloplasmin (CP. With serum level of malondialdehyde we monitored the presence of the lipid peroxidation by the reactive oxygen species, and with the oxidized ceruloplasmin level in blood serum we evidenced the activity of antioxidant system in blood.

  4. The Effects of Nonuniform Illumination on the Electrical Performance of a Single Conventional Photovoltaic Cell

    Directory of Open Access Journals (Sweden)

    Damasen Ikwaba Paul

    2015-01-01

    Full Text Available Photovoltaic (PV concentrators are a promising approach for lowering PV electricity costs in the near future. However, most of the concentrators that are currently used for PV applications yield nonuniform flux profiles on the surface of a PV module which in turn reduces its electrical performance if the cells are serially connected. One way of overcoming this effect is the use of PV modules with isolated cells so that each cell generates current that is proportional to the energy flux absorbed. However, there are some cases where nonuniform illumination also exists in a single cell in an isolated cells PV module. This paper systematically studied the effect of nonuniform illumination on various cell performance parameters of a single monocrystalline standard PV cell at low and medium energy concentration ratios. Furthermore, the effect of orientation, size, and geometrical shapes of nonuniform illumination was also investigated. It was found that the effect of nonuniform illumination on various PV cell performance parameters of a single standard PV cell becomes noticeable at medium energy flux concentration whilst the location, size, and geometrical shape of nonuniform illumination have no effect on the performance parameters of the cell.

  5. Preliminary design and analysis of aluminum-air cells providing for continuous feed and full utilization of anodes

    Science.gov (United States)

    Cooper, J. F.

    1981-08-01

    The advantages, disadvantages, and engineering problem areas of the wedge shaped cells in anodes utilization are reviewed. The importance of solution side current collection to the practicality of this approach when used with alkaline electrolytes is identified. The relationship between cell height and total anode mass is derived for this and corresponding cells of the M1 design. It is concluded that the M1-CF design may provide the basis for an automotive battery of greater simplicity, reliability, and economy than earlier designs.

  6. Effect of a dual task on quantitative Timed Up and Go performance in community-dwelling older adults: A preliminary study.

    Science.gov (United States)

    Smith, Erin; Walsh, Lorcan; Doyle, Julie; Greene, Barry; Blake, Catherine

    2017-08-01

    The Timed Up and Go test (TUG) is used as a measure of functional ability in older adults; however, the method of measurement does not allow us to determine which aspects of the test deficits occur in. The aim of the present study was to examine the ability of the quantitative TUG (QTUG) to measure performance during the TUG test under three different conditions - single task, motor task and cognitive dual task - and to compare performance between fallers and non-fallers in high-functioning community-dwelling older adults. A total of 37 community-dwelling older adults, 16 with a self-reported falls history in the previous year, were recruited. Participants underwent a falls risk assessment with a physiotherapist including the QTUG under three conditions (single task, motor task, cognitive dual-task). A total of 10 clinical parameters were chosen for analysis using mancova and a series of ancova, with age, sex and body mass index included as covariates. The mancova analysis showed a significant difference across the three task conditions (Wilk's Lambda F 20,186  = 3.37, P task and faller status (Wilk's Lambda F 20,192  = 1.131, P = 0.321) was found. ancova results for each of the parameters showed overall differences between single, motor and cognitive tasks for all of the variables, except time in double support. When faller and non-faller differences were explored, cadence and stride velocity was greater, and stride time longer in those with a prior history of falls. In community-dwelling older adults, these preliminary results show that a cognitive dual-task significantly (P performance in almost all parameters, with a significant (P task. Although no statistical difference was found between fallers and non-fallers for many of the parameters, cadence, stride time and stride velocity were statistically different (P performance under dual-task conditions between fallers and non-fallers in this population, and to look at the ability of dual

  7. Numerical study of assembly pressure effect on the performance of proton exchange membrane fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Taymaz, Imdat; Benli, Merthan [Department of Mechanical Engineering, University of Sakarya, 54187 Adapazari (Turkey)

    2010-05-15

    The performance of the fuel cell is affected by many parameters. One of these parameters is assembly pressure that changes the mechanical properties and dimensions of the fuel cell components. Its first duty, however, is to prevent gas or liquid leakage from the cell and it is important for the contact behaviors of fuel cell components. Some leakage and contact problems can occur on the low assembly pressures whereas at high pressures, components of the fuel cell, such as bipolar plates (BPP), gas diffusion layers (GDL), catalyst layers, and membranes, can be damaged. A finite element analysis (FEA) model is developed to predict the deformation effect of assembly pressure on the single channel PEM fuel cell in this study. Deformed fuel cell single channel model is imported to three-dimensional, computational fluid dynamics (CFD) model which is developed for simulating proton exchange membrane (PEM) fuel cells. Using this model, the effect of assembly pressure on fuel cell performance can be calculated. It is found that, when the assembly pressure increases, contact resistance, porosity and thickness of the gas diffusion layer (GDL) decreases. Too much assembly pressure causes GDL to destroy; therefore, the optimal assembly pressure is significant to obtain the highest performance from fuel cell. By using the results of this study, optimum fuel cell design and operating condition parameters can be predicted accordingly. (author)

  8. Concomitant boost radiation therapy for inoperable non-small-cell lung cancer: preliminary report of a prospective randomized study

    International Nuclear Information System (INIS)

    Sun, L.-M.; Leung, Stephen Wan; Wang, C.-J.; Chen, H.-C.; Fang, F.-M.; Huang, E.-Y.; Hsu, H.-C.; Yeh, S.-A.; Hsiung, C.-Y.; Huang, David T.

    2000-01-01

    Purpose: The radiation therapy results for patients with inoperable non-small-cell lung cancer (NSCLC) have been disappointing. Tumor dose escalation using concomitant boost technique (CBT) has been shown to improve local control in a few prospective studies. This trial was carried out to prospectively assess the radiation response and acute toxicity of CBT in comparison to the conventional treatment technique (CTT). Methods and Materials: Ninety-seven consecutive eligible patients were entered in this prospective clinical trial between November 1994 and February 1998. Patients were randomized to receive either CBT (43 patients) or CTT (54 patients) radiation therapy. These patients either refused chemotherapy or were judged as unsuitable for chemotherapy. Patients in the CBT group received 46.8 Gy in 26 fractions using large fields that encompassed the gross and occult disease. A concomitant boost of 18.2 Gy (0.7 Gy per fraction) was delivered to the gross disease using small fields with 1.5-cm margins. The small fields were treated concurrently with the large fields and the total dose to the tumor area was 65 Gy in 26 fractions. Patients in the CTT group received 70.8 Gy in 38 fractions. The acute toxicity between each group was compared. The response rate was analyzed and compared by treatment group, gender, age, stage, histology, initial Karnofsky performance score (KPS), severity of acute toxicity, and maximum body weight loss (MBWL) during treatment course. Results: The demographic parameters such as sex, age, and stage were evenly distributed in each treatment group. The majority of these patients had Stage IIIA and IIIB disease. Overall median treatment times were 39 days for the CBT group of patients and 62 days for the CTT group. No treatment-related mortality was found. There were 2 patients in the CTT group with acute RTOG Grade 3 lung toxicity, and no Grade 3 lung or esophageal toxicity was observed in CBT group. The response rates, assessed by

  9. Performance of direct alcohol fuel cells fed with mixed methanol/ethanol solutions

    Energy Technology Data Exchange (ETDEWEB)

    Wongyao, N. [The Joint Graduate School of Energy and Environment, King Mongkut' s University of Technology Thonburi, 126 Pracha-Uthit Rd., Bang Mod, Thung Khru, Bangkok 10140 (Thailand); Therdthianwong, A., E-mail: apichai.the@kmutt.ac.t [Fuel Cell and Hydrogen Research and Engineering Center, Clean Energy System Group, PDTI, King Mongkut' s University of Technology Thonburi, 126 Pracha-Uthit Rd., Bang Mod, Thung Khru, Bangkok 10140 (Thailand); Therdthianwong, S. [Department of Chemical Engineering, Faculty of Engineering, King Mongkut' s University of Technology Thonburi, 126 Pracha-Uthit Rd., Bang Mod, Thung Khru, Bangkok 10140 (Thailand)

    2011-07-15

    Research highlights: {yields} We examined the performance of direct alcohol fuel cells fed with mixed alcohol. {yields} PtRu-PtSn/C and PtRu/C as catalysts for mixed alcohol electrooxidation reaction. {yields} Misplace adsorption of ethanol on PtRu/C caused the cell performance drop. {yields} PtRu/C showed higher performance than PtRu-PtSn/C for mixed alcohol fuel. -- Abstract: In combining the advantages of both methanol and ethanol, direct alcohol fuel cells fed with mixed alcohol solutions (1 M methanol and 1 M ethanol in varying volume ratios) were tested for performance. Employing a PtRu-PtSn/C catalyst as anode, cell performance was found to diminish rapidly even at 2.5% by volume ethanol mixture. Further increase of ethanol exceeded 10%, the cell performance gradually decreased and finally approached that of direct ethanol fuel cells. The causes of the decrease in the cell performance were the slow electro-oxidation of ethanol and the misplaced adsorption of ethanol on PtRu/C. By comparing the PtRu-PtSn/C cell with the PtRu/C cell operated with mixed alcohol solutions, the cell using PtRu/C as an anode catalyst provided higher power density since more PtRu/C surface was available for methanol oxidation reaction and less ohmic resistance of PtRu/C than that of PtRu-PtSn/C. In order to reach optimization of DAFC performance fed with mixed alcohol, the electrocatalyst used for the anode must selectively adsorb an alcohol, especially ethanol.

  10. Performance of direct alcohol fuel cells fed with mixed methanol/ethanol solutions

    International Nuclear Information System (INIS)

    Wongyao, N.; Therdthianwong, A.; Therdthianwong, S.

    2011-01-01

    Research highlights: → We examined the performance of direct alcohol fuel cells fed with mixed alcohol. → PtRu-PtSn/C and PtRu/C as catalysts for mixed alcohol electrooxidation reaction. → Misplace adsorption of ethanol on PtRu/C caused the cell performance drop. → PtRu/C showed higher performance than PtRu-PtSn/C for mixed alcohol fuel. -- Abstract: In combining the advantages of both methanol and ethanol, direct alcohol fuel cells fed with mixed alcohol solutions (1 M methanol and 1 M ethanol in varying volume ratios) were tested for performance. Employing a PtRu-PtSn/C catalyst as anode, cell performance was found to diminish rapidly even at 2.5% by volume ethanol mixture. Further increase of ethanol exceeded 10%, the cell performance gradually decreased and finally approached that of direct ethanol fuel cells. The causes of the decrease in the cell performance were the slow electro-oxidation of ethanol and the misplaced adsorption of ethanol on PtRu/C. By comparing the PtRu-PtSn/C cell with the PtRu/C cell operated with mixed alcohol solutions, the cell using PtRu/C as an anode catalyst provided higher power density since more PtRu/C surface was available for methanol oxidation reaction and less ohmic resistance of PtRu/C than that of PtRu-PtSn/C. In order to reach optimization of DAFC performance fed with mixed alcohol, the electrocatalyst used for the anode must selectively adsorb an alcohol, especially ethanol.

  11. Fuel Cell Power Plant Initiative. Volume II: Preliminary Design of a Fixed-Base LFP/SOFC Power System

    National Research Council Canada - National Science Library

    Veyo, S

    1997-01-01

    .... Fuel cells are electrochemical devices that directly convert the chemical energy contained in fuels such as hydrogen, natural gas, or coal gas into electricity at high efficiency with no intermediate...

  12. Disruptive effect of Dzyaloshinskii-Moriya interaction on the magnetic memory cell performance

    Energy Technology Data Exchange (ETDEWEB)

    Sampaio, J.; Cubukcu, M.; Cros, V.; Reyren, N., E-mail: nicolas.reyren@thalesgroup.com [Unité Mixte de Physique, CNRS, Thales, Univ. Paris-Sud, Université Paris-Saclay, 91767, Palaiseau (France); Khvalkovskiy, A. V. [Samsung Electronics, Semiconductor R& D Center (Grandis), San Jose, California 95134 (United States); Moscow Institute of Physics and Technology, State University, Moscow 141700 (Russian Federation); Kuteifan, M.; Lomakin, V. [Department of Electrical and Computer Engineering, University of California at San Diego, La Jolla, California 92093-0407 (United States); Apalkov, D. [Samsung Electronics, Semiconductor R& D Center (Grandis), San Jose, California 95134 (United States)

    2016-03-14

    In order to increase the thermal stability of a magnetic random access memory cell, materials with high spin-orbit interaction are often introduced in the storage layer. As a side effect, a strong Dzyaloshinskii-Moriya interaction (DMI) may arise in such systems. Here, we investigate the impact of DMI on the magnetic cell performance, using micromagnetic simulations. We find that DMI strongly promotes non-uniform magnetization states and non-uniform switching modes of the magnetic layer. It appears to be detrimental for both the thermal stability of the cell and its switching current, leading to considerable deterioration of the cell performance even for a moderate DMI amplitude.

  13. hTERT gene immortalized human adipose-derived stem cells and its multiple differentiations: a preliminary investigation.

    Science.gov (United States)

    Wang, L; Song, K; Qu, X; Wang, H; Zhu, H; Xu, X; Zhang, M; Tang, Y; Yang, X

    2013-03-01

    Human adipose-derived adult stem cells (hADSCs) can express human telomerase reverse transcriptase phenotypes under an appropriate culture condition. Because adipose tissue is abundant and easily accessible, hADSCs offer a promising source of stem cells for tissue engineering application and other cell-based therapies. However, the shortage of cells number and the difficulty to proliferate, known as the "Hayflick limit" in vitro, limit their further clinical application. Here, hADSCs were transfected with human telomerase reverse transcriptase (hTERT) gene by the lentiviral vector to prolong the lifespan of stem cells and even immortalize them. Following to this, the cellular properties and functionalities of the transfected cell lines were assayed. The results demonstrated that hADSCs had been successfully transfected with hTERT gene (hTERT-ADSCs). Then, hTERT-ADSCs were initially selected by G418 and subsequently expanded over 20 passages in vitro. Moreover, the qualitative and quantitative differentiation criteria for 20 passages of hTERT-ADSCs also demonstrated that hTERT-ADSCs could differentiate into osteogenesis, chondrogenesis, and adipogenesis phenotypes in lineage-specific differentiation media. These findings confirmed that this transfection could prolong the lifespan of hADSCs.

  14. In Vitro Exposure of Porcine Ovarian Follicular Cells to PCB 153 Alters Steroid Secretion But Not Their Viability—Preliminary Study

    Directory of Open Access Journals (Sweden)

    Ewa L. Gregoraszczuk

    2002-01-01

    Full Text Available In our previous paper[1], we demonstrated that porcine follicles collected during the early stage of development are the most sensitive to the toxic action of polychlorinated biphenyl 153 (PCB 153. Follicles of this type were collected to test the effect of PCB 153 on cell steroidogenesis and viability. Cocultures of granulosa and theca cells were grown in M199 medium at 37ºC. Control cultures were maintained in that medium alone, while experimental ones were supplemented with PCB 153 at doses of 5, 10, 50, and 100 ng/ml. After 48, 96, and 144 h, media were collected for steroid analysis and cell viability was measured using an LDH (lactate dehydrogenase activity cytotoxicity test. A 2-day exposure of follicular cells to all the investigated doses of PCB 153 caused a statistically significant decrease in progesterone (P4 secretion, while in doses of 50 and 100 ng/ml there was also a decrease in testosterone (T secretion. No effect on estradiol (E2 secretion was observed. The observed decrease in P4 and T secretion, and lack of any statistically significant effect on E2 secretion by cells from small follicles exposed for 48 h to PCB, suggests that PCB 153 acts before P4 formation. Longer exposures caused an increase in P4 secretion, with a concomitant drastic decrease in T secretion and a tendency to decrease the E2 secretion, suggesting inhibition of P450 17α hydroxysteroid dehydrogenase, an enzyme that converts P4 to T. The observed PCB 153–induced increase in P4 secretion by cells collected from small antral follicles, with a concomitant decrease in E2 secretion, accounts for the induction of luteinization and, in this case, inhibition of aromatization process in the follicles. However, in all doses tested and at all times of exposure, PCB 153 had no effect on cell viability. These findings suggest different time of exposure–dependent action of PCB 153 on particular steps of steroidogenesis but not action on cell viability. These results

  15. Hybrid Direct Carbon Fuel Cell Performance with Anode Current Collector Material

    DEFF Research Database (Denmark)

    Deleebeeck, Lisa; Kammer Hansen, Kent

    2015-01-01

    collectors were studied: Au, Ni, Ag, and Pt. It was shown that the performance of the direct carbon fuel cell (DCFC) is dependent on the current collector materials, Ni and Pt giving the best performance, due to their catalytic activity. Gold is suggested to be the best material as an inert current collector......The influence of the current collector on the performance of a hybrid direct carbon fuel cell (HDCFC), consisting of solid oxide fuel cell (SOFC) with a molten carbonate-carbon slurry in contact with the anode, has been investigated using current-voltage curves. Four different anode current...

  16. Modular Approach for Continuous Cell-Level Balancing to Improve Performance of Large Battery Packs: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Muneed ur Rehman, M.; Evzelman, M.; Hathaway, K.; Zane, R.; Plett, G. L.; Smith, K.; Wood, E.; Maksimovic, D.

    2014-10-01

    Energy storage systems require battery cell balancing circuits to avoid divergence of cell state of charge (SOC). A modular approach based on distributed continuous cell-level control is presented that extends the balancing function to higher level pack performance objectives such as improving power capability and increasing pack lifetime. This is achieved by adding DC-DC converters in parallel with cells and using state estimation and control to autonomously bias individual cell SOC and SOC range, forcing healthier cells to be cycled deeper than weaker cells. The result is a pack with improved degradation characteristics and extended lifetime. The modular architecture and control concepts are developed and hardware results are demonstrated for a 91.2-Wh battery pack consisting of four series Li-ion battery cells and four dual active bridge (DAB) bypass DC-DC converters.

  17. Organic Solar Cells: Degradation Processes and Approaches to Enhance Performance

    Energy Technology Data Exchange (ETDEWEB)

    Fungura, Fadzai [Iowa State Univ., Ames, IA (United States)

    2016-12-17

    Intrinsic photodegradation of organic solar cells, theoretically attributed to C-H bond rearrangement/breaking, remains a key commercialization barrier. This work presents, via dark electron paramagnetic resonance (EPR), the first experimental evidence for metastable C dangling bonds (DBs) (g=2.0029±0.0004) formed by blue/UV irradiation of polymer:fullerene blend films in nitrogen. The DB density increased with irradiation and decreased ~4 fold after 2 weeks in the dark. The dark EPR also showed increased densities of other spin-active sites in photodegraded polymer, fullerene, and polymer:fullerene blend films, consistent with broad electronic measurements of fundamental properties, including defect/gap state densities. The EPR enabled identification of defect states, whether in the polymer, fullerene, or at the donor/acceptor (D/A) interface. Importantly, the EPR results indicate that the DBs are at the D/A interface, as they were present only in the blend films. The role of polarons in interface DB formation is also discussed.

  18. Performance of 500 m3 TankCell® at Kevitsa Cu-Ni-PGM concentrator

    Directory of Open Access Journals (Sweden)

    Mattsson Toni

    2016-01-01

    Full Text Available Outotec TankCell e500 flotation cell, with 500 m3 of efficient flotation volume, has been in operation since October 2014 at Kevitsa Cu-Ni-PGM concentrator as the first Cu rougher flotation cell. The 500 m3 flotation cell has proven to provide metallurgical superiority at very low specific power. On average the cell has recovered 71% of copper contained in the flotation feed. The cell has produced the concentrate with the Cu grade equal to 17% Cu. The typical specific power for the cell is around 0.4 kW/m3 (blower power not included. After the start-up of the cell the operating parameters have varied. The mixing speed have varied from 4.9 to 7.0 m/s and the superficial gas velocity from 0.3 to 1.5 cm/s. At various operating parameters the mixing, gas dispersion and metallurgical performance of the cell have been evaluated. In this paper a review of the hydrodynamic and metallurgical performance of the cell is presented. The paper focuses on the interactions of mixing intensity, bubble size and metallurgical performance in industrial application.

  19. Preliminary studies of the effects of gadolinium texaphyrin on the growth and radiosensitivity of EMT6 cells in vitro

    International Nuclear Information System (INIS)

    Rockwell, Sara; Donnelly, Erling T.; Liu Yanfeng; Tang Liqun

    2002-01-01

    Purpose: To investigate the effects of gadolinium texaphyrin (GdTx) on the growth and radiation response of cells in vitro, in a limited set of experiments designed to examine some areas of controversy concerning the effects of this compound. Methods and Materials: Exponentially growing cultures of EMT6 mouse mammary tumor cells, grown in Dulbecco's Modified Eagle's Medium with 10% dialyzed fetal bovine serum, were treated with GdTx either prepared from powder or obtained as a solution similar to that used clinically, in either the presence or absence of equimolar ascorbic acid. Cell viability was measured using a clonogenic assay. Results: Treatment with GdTx in the presence of ascorbic acid dramatically altered the growth, appearance, and behavior of the cells; treatment with GdTx in the absence of ascorbic acid had only minimal effects. The effects of the powdered drug and the solution were similar. GdTx used with equimolar ascorbic acid altered the radiation dose-response curves of cells irradiated under aerobic and hypoxic conditions; no significant changes were observed without ascorbic acid. Conclusions: The details of the protocols used in experiments examining the effects of GdTx have major effects on the outcomes. Our results suggest that differences in the protocols used by different groups in past studies with GdTx probably were important in producing the disparate results reported previously

  20. Preliminary viability studies of fibroblastic cells cultured on microcrystalline and nanocrystalline diamonds produced by chemical vapour deposition method

    Directory of Open Access Journals (Sweden)

    Ana Amélia Rodrigues

    2013-02-01

    Full Text Available Implant materials used in orthopedics surgery have demonstrated some disadvantages, such as metallic corrosion processes, generation of wear particles, inflammation reactions and bone reabsorption in the implant region. The diamond produced through hot-filament chemical vapour deposition method is a new potential biomedical material due to its chemical inertness, extreme hardness and low coefficient of friction. In the present study we analysis two samples: the microcrystalline diamond and the nanocrystalline diamond. The aim of this study was to evaluate the surface properties of the diamond samples by scanning electron microscopy, Raman spectroscopy and atomic force microscopy. Cell viability and morphology were assessed using thiazolyl blue tetrazolium bromide, cytochemical assay and scanning electron microscopy, respectively. The results revealed that the two samples did not interfere in the cell viability, however the proliferation of fibroblasts cells observed was comparatively higher with the nanocrystalline diamond.

  1. The preliminary study on the inductory signal triggering the error-prone DNA repair function in mammalian cells

    International Nuclear Information System (INIS)

    Su Zaozhong; Luo Zuyu

    1989-01-01

    The nature of the signal triggering error-prone DNA repair function in mammalian cells was studied from two notions: (1) Does the inducing signal result from the direct hitting the cellular targets by DNA-damaging agents? (2) Is inhibition of DNA replication a prerequisite condition for the triggering effect? Thus, the ultraviolet (UV)-irradiated exogenous DNAs were introduced into human and rat cells by transfection. The results showed that this transfection was able to induce the error-prone repair as efficient as direct UV-irradiation to cells. Moreover, the two inductory treaetments expressed similar kinetics and dose-responses. No matter whether the introduced DNAs initiated replication, they exhibited the incuctory activity. Therefore, it can be considered that DNA lesions itself, not the direct interaction of DNA-damaging agents with specific cellular targets, serve as a triggering signal for the inductory process. Inhibition of DNA replication is not a prerequisite for the inductory signal

  2. Costly Cell Phones: The Impact of Cell Phone Rings on Academic Performance

    Science.gov (United States)

    End, Christian M.; Worthman, Shaye; Mathews, Mary Bridget; Wetterau, Katharina

    2010-01-01

    College students participated in a study on the "psychology of note taking" during which they took notes on video content and later completed a multiple-choice test on the material. Researchers assigned 71 participants to either the ringing condition (the video was disrupted by a ringing cell phone) or the control condition (no cell phone rings…

  3. Expression, crystallization and preliminary crystallographic analysis of the extracellular IgV-like domain of the human natural killer cell inhibitory receptor p75/AIRM1.

    Science.gov (United States)

    Dimasi, Nazzareno; Moretta, Lorenzo; Biassoni, Roberto; Mariuzza, Roy A

    2003-10-01

    p75/AIRM1 (Siglec-7) is a sialic acid-binding Ig-like lectin recently identified as an inhibitory receptor on natural killer cells. The expression, in vitro folding, circular-dichroism spectroscopy, crystallization and preliminary X-ray characterization of the Ig-V like domain of p75/AIRM1 are reported. X-ray data were collected from a single crystal at 100 K, with a maximum useful diffraction pattern extending to 1.45 A resolution on a synchrotron source. The crystal belongs to a primitive monoclinic space group, with unit-cell parameters a = 32.65, b = 49.72, c = 39.79 A, alpha = gamma = 90, beta = 113 degrees. The systematic absences indicate that the space group is P2(1). Assuming one molecule per asymmetric unit, V(M) (the Matthews coefficient) was calculated to be 1.879 A(3) Da(-1) and the solvent content was estimated to be 32.01%.

  4. Preliminary 19F-MRS Study of Tumor Cell Proliferation with 3′-deoxy-3′-fluorothymidine and Its Metabolite (FLT-MP

    Directory of Open Access Journals (Sweden)

    In Ok Ko

    2017-01-01

    Full Text Available The thymidine analogue 3′-deoxy-3′-[18F]fluorothymidine, or [18F]fluorothymidine ([18F]FLT, is used to measure tumor cell proliferation with positron emission tomography (PET imaging technology in nuclear medicine. FLT is phosphorylated by thymidine kinase 1 (TK1 and then trapped inside cells; it is not incorporated into DNA. Imaging with 18F-radiolabeled FLT is a noninvasive technique to visualize cellular proliferation in tumors. However, it is difficult to distinguish between [18F]FLT and its metabolites by PET imaging, and quantification has not been attempted using current imaging methods. In this study, we successfully acquired in vivo F19 spectra of natural or nonradioactive 3′-deoxy-3′-fluorothymidine ([19F]FLT and its monophosphate metabolite (FLT-MP in a tumor xenograft mouse model using 9.4T magnetic resonance imaging (MRI. This preliminary result demonstrates that 19F magnetic resonance spectroscopy (MRS with FLT is suitable for the in vivo assessment of tumor aggressiveness and for early prediction of treatment response.

  5. Detection of micro RNA hsa-let-7e in peripheral blood mononuclear cells infected with dengue virus serotype-2: preliminary study

    Science.gov (United States)

    Masyeni, S.; Hadi, U.; Kuntaman; Yohan, B.; Margyaningsih, N. I.; Sasmono, R. T.

    2018-03-01

    Pathogenesis of dengue infection is still obscure. Recently, the role of microRNA has been associated with the cytokine storm which leads to plasma leakage in endothelial cells. The objective of our study was to determine whether particular microRNA is overexpressed in PBMCs infected with DENV and to assess its correlation to the expression of suppressor of cytokine signaling 3 (SOCS3) proteins to increase the production of pro-inflammatory cytokines. We report the result of a preliminary study on the expression of microRNA hsa-let-7e. The peripheral blood mononuclear cells (PBMCs) from the healthy volunteer were infected with the clinical isolate of DENV-2. RNA was extracted with miRCURYLNATMExiqon. Quantitative Real-Time PCR was used to measure the relative expression of hsa-let-7e micro RNA and the mRNA of SOCS3 proteins. MicroRNA hsa-let-7e expression was increased in PBMCs upon DENV-2 infection. The relative expression of hsa-let-7e is detected at 1.46 folds relative to uninfected PBMCs in 4 hours post-infection and decreased in 19 hours post infection. In contrast, the expression of mRNA of SOCS3 was inversely expressed with hsa-let-7 expression. MicroRNA was overexpressed in PBMCs upon infection with DENV-2. This microRNA may bind the SOCS3 and contribute to the pathogenesis of dengue infection.

  6. The effect of nitrogen oxides in air on the performance of proton exchange membrane fuel cell

    International Nuclear Information System (INIS)

    Yang Daijun; Ma Jianxin; Xu Lin; Wu Minzhong; Wang Haijiang

    2006-01-01

    The effects of NO x on the performance of proton exchange membrane (PEM) fuel cell were investigated through the introduction of a mixture containing NO and NO 2 , in a ratio of 9:1, into the cathode stream of a single PEM fuel cell. The NO x concentrations used in the experiments were 1480 ppm, 140 ppm and 10 ppm, which cover a range of three orders. The experimental results obtained from the tests of durability, polarization, reversibility and electrochemical impedance spectroscopy (EIS) showed a detrimental effect of NO x on the cell performance. The electrochemical measurements results suggested that the impacts of NO x are mainly resulted from the superposition of the oxygen reduction reaction (ORR), NO and HNO 2 oxidation reactions, and the increased cathodic impedance. Complete recovery of the cell performance was reached after operating the cell with clean air and then purging with N 2 for hours

  7. Long Term Performance Study of a Direct Methanol Fuel Cell Fed with Alcohol Blends

    Directory of Open Access Journals (Sweden)

    Eleuterio Mora

    2013-01-01

    Full Text Available The use of alcohol blends in direct alcohol fuel cells may be a more environmentally friendly and less toxic alternative to the use of methanol alone in direct methanol fuel cells. This paper assesses the behaviour of a direct methanol fuel cell fed with aqueous methanol, aqueous ethanol and aqueous methanol/ethanol blends in a long term experimental study followed by modelling of polarization curves. Fuel cell performance is seen to decrease as the ethanol content rises, and subsequent operation with aqueous methanol only partly reverts this loss of performance. It seems that the difference in the oxidation rate of these alcohols may not be the only factor affecting fuel cell performance.

  8. Preliminary Investigation of Myo-Inositol Phosphates Produced by ASUIA279 Phytase on MCF-7 Cancer Cells

    Directory of Open Access Journals (Sweden)

    N. Mohd. Yusoff

    2011-12-01

    Full Text Available Phytate or myo-inositol hexakisphosphates (IP6 is widely distributed in plants like rice brans. The production of myo-inositol phosphate intermediates has received much attention due to the remarkable potential health benefits offered by the compounds. In this study, the cytotoxicity of the partially purified myo-inositol phosphate fractions and commercial IP1 and IP6 were investigated against MCF-7 breast cancer cell lines. The study showed that the commercial standard IP1 and IP6 showed good inhibition towards the MCF-7 cell line. The MCF-7 cells growth was inhibited in minimum concentration of myo-inositol phosphates (<1000 µg/ml. However, no inhibition observed on the MCF-7 cell line by the myo-inositol phosphates fractions partially purified from rice bran at concentration <1000 ?g/ml. The inhibition of MCF-7 was only observed at concentration more than 30 mg/ml with more than 40% cells were inhibited. This indicates that the partially purified rice bran myo-inositol phosphates degraded by ASUIA279 phytase on MCF-7 breast cancer cells exhibit positive results towards the inhibition of cancer cells growth at relatively high concentration..KEYWORDS: myo-inositol phosphates, phytase, MCF-7,  cancerABSTRAK: Fitat atau myo-inositol hexakisphosphate (IP6 dikenali umum teragih di dalam tumbuhan seperti dedak padi. Penghasilan perantaraan fosfat myo-inositol mendapat perhatian memandangkan ia berpotensi tinggi dalam kesihatan. Dalam kajian ini, kesitotoksikan sebahagian daripada fosfat myo-inositol separa tulen, IP1 komersil dan IP6 komersil dikaji terhadap produk yang berupa sel kekal (cell lines kanser payu dara MCF-7. Tumbesaran sel MCF-7 direncatkan dalam pekatan minima fosfat myo-inositol (<1000 μg/ml. Tetapi, tidak ada perencatan dilihat terhadap sel kekal MCF-7 oleh sebahagian fosfat myo-inositol separa tulen daripada dedak padi pada kepekatan <1000 mg/ml. Perencatan MCF-7 hanya dilihat pada kepekatan lebih daripada 30 mg/ml dengan lebih

  9. Modelling of proton exchange membrane fuel cell performance based on semi-empirical equations

    Energy Technology Data Exchange (ETDEWEB)

    Al-Baghdadi, Maher A.R. Sadiq [Babylon Univ., Dept. of Mechanical Engineering, Babylon (Iraq)

    2005-08-01

    Using semi-empirical equations for modeling a proton exchange membrane fuel cell is proposed for providing a tool for the design and analysis of fuel cell total systems. The focus of this study is to derive an empirical model including process variations to estimate the performance of fuel cell without extensive calculations. The model take into account not only the current density but also the process variations, such as the gas pressure, temperature, humidity, and utilization to cover operating processes, which are important factors in determining the real performance of fuel cell. The modelling results are compared well with known experimental results. The comparison shows good agreements between the modeling results and the experimental data. The model can be used to investigate the influence of process variables for design optimization of fuel cells, stacks, and complete fuel cell power system. (Author)

  10. Topological cell clustering in the ATLAS calorimeters and its performance in LHC Run 1

    Energy Technology Data Exchange (ETDEWEB)

    Aad, G. [CPPM, Aix-Marseille Univ. et CNRS/IN2P3, Marseille (France); Abbott, B. [Oklahoma Univ., Norman, OK (United States). Homer L. Dodge Dept. of Physics and Astronomy; Abdallah, J. [Academia Sinica, Taipei (China). Inst. of Physics; Collaboration: ATLAS Collaboration; and others

    2017-07-15

    The reconstruction of the signal from hadrons and jets emerging from the proton-proton collisions at the Large Hadron Collider (LHC) and entering the ATLAS calorimeters is based on a three-dimensional topological clustering of individual calorimeter cell signals. The cluster formation follows cell signal-significance patterns generated by electromagnetic and hadronic showers. In this, the clustering algorithm implicitly performs a topological noise suppression by removing cells with insignificant signals which are not in close proximity to cells with significant signals. The resulting topological cell clusters have shape and location information, which is exploited to apply a local energy calibration and corrections depending on the nature of the cluster. Topological cell clustering is established as a well-performing calorimeter signal definition for jet and missing transverse momentum reconstruction in ATLAS. (orig.)

  11. Study of double porous silicon surfaces for enhancement of silicon solar cell performance

    Science.gov (United States)

    Razali, N. S. M.; Rahim, A. F. A.; Radzali, R.; Mahmood, A.

    2017-09-01

    In this work, design and simulation of double porous silicon surfaces for enhancement of silicon solar cell is carried out. Both single and double porous structures are constructed by using TCAD ATHENA and TCAD DEVEDIT tools of the SILVACO software respectively. After the structures were created, I-V characteristics and spectral response of the solar cell were extracted using ATLAS device simulator. Finally, the performance of the simulated double porous solar cell is compared with the performance of both single porous and bulk-Si solar cell. The results showed that double porous silicon solar cell exhibited 1.8% efficiency compared to 1.3% and 1.2% for single porous silicon and bulk-Si solar cell.

  12. Characteristics of Labial Gland Mesenchymal Stem Cells of Healthy Individuals and Patients with Sjögren's Syndrome: A Preliminary Study.

    Science.gov (United States)

    Wang, Shi-Qin; Wang, Yi-Xiang; Hua, Hong

    2017-08-15

    Sjögren's syndrome (SS) is a systemic autoimmune disease that is characterized by focal lymphocytic infiltration into exocrine organs such as salivary and lacrimal glands, resulting in dry mouth and eyes, and other systemic injuries. There is no curative clinical therapy for SS, and stem cell therapy has shown great potential in this area. The mesenchymal stem cells (MSCs) in the salivary glands of healthy individuals and in patients with SS have not been extensively studied. The aim of this study was to elucidate the characteristics of MSCs from the labial glands of healthy controls and of those from patients with SS to elucidate the related pathogenesis and to uncover potential avenues for novel clinical interventions. Labial glands from patients with SS and healthy subjects were obtained, and MSCs were isolated and cultured by using the tissue adherent method. The MSC characteristics of the cultured cells were confirmed by using morphology, proliferation, colony forming-unit (CFU) efficiency, and multipotentiality, including osteogenic, adipogenic, and salivary gland differentiation. The MSCs from the healthy controls and SS patients expressed characteristic MSC markers, including CD29, CD44, CD73, CD90, and CD105; they were negative for CD34, CD45, and CD106, and also negative for the salivary gland epithelium markers (CD49f and CD117). Labial gland MSCs from both groups were capable of osteogenic and adipogenic differentiation. The CFU efficiency and adipogenic differentiation potential of MSCs were significantly lower in the SS group compared with the healthy controls. Cells from both groups could also be induced into salivary gland-like cells. Real-time polymerase chain reaction and immunofluorescence staining showed that the gene and protein expression of AMY1, AQP5, and ZO-1 in cells from the SS group was lower than that in cells from the healthy group. Thus, MSCs from the labial glands in patients with SS could lack certain characteristics and functions

  13. Characterization of high performance silicon-based VMJ PV cells for laser power transmission applications

    Science.gov (United States)

    Perales, Mico; Yang, Mei-huan; Wu, Cheng-liang; Hsu, Chin-wei; Chao, Wei-sheng; Chen, Kun-hsien; Zahuranec, Terry

    2016-03-01

    Continuing improvements in the cost and power of laser diodes have been critical in launching the emerging fields of power over fiber (PoF), and laser power beaming. Laser power is transmitted either over fiber (for PoF), or through free space (power beaming), and is converted to electricity by photovoltaic cells designed to efficiently convert the laser light. MH GoPower's vertical multi-junction (VMJ) PV cell, designed for high intensity photovoltaic applications, is fueling the emergence of this market, by enabling unparalleled photovoltaic receiver flexibility in voltage, cell size, and power output. Our research examined the use of the VMJ PV cell for laser power transmission applications. We fully characterized the performance of the VMJ PV cell under various laser conditions, including multiple near IR wavelengths and light intensities up to tens of watts per cm2. Results indicated VMJ PV cell efficiency over 40% for 9xx nm wavelengths, at laser power densities near 30 W/cm2. We also investigated the impact of the physical dimensions (length, width, and height) of the VMJ PV cell on its performance, showing similarly high performance across a wide range of cell dimensions. We then evaluated the VMJ PV cell performance within the power over fiber application, examining the cell's effectiveness in receiver packages that deliver target voltage, intensity, and power levels. By designing and characterizing multiple receivers, we illustrated techniques for packaging the VMJ PV cell for achieving high performance (> 30%), high power (> 185 W), and target voltages for power over fiber applications.

  14. Synthesis and preliminary evaluation of 9-(4-[{sup 18}F]fluoro-3-hydroxymethylbutyl) guanine ([{sup 18}F]FHBG) in HSV1-tk gene transduced hepatoma cell

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Byung Seok; Lee, Tae Sup [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of); Lee, Myoung Keun [Yonsei University, Wonju (Korea, Republic of)] (and others)

    2006-08-15

    The HSV1-tk reporter gene system is the most widely used system because of its advantage that direct monitoring is possible without the introduction of a separate reporter gene in case of HSV1-tk suicide gene therapy. In this study, we investigate the usefulness of the reporter probe (substrate), 9-(4-[{sup 18}F]fluoro-3-hydroxymethylbutyl) guanine ([{sup 18}F]FHBG) for non-invasive reporter gene imaging using PET in HSV1-tk expressing hepatoma model. Radiolabeled FHBG was prepared in 8 steps from a commercially available triester. The labeling reaction was carried out by NCA nucleophilic substitution with K[{sup 18}F]/K2.2.2. in acetonitrile using N2-monomethoxytrityl-9-[4-(tosly)-3-monomethoxytritylmethylbutl] guanine as a precursor, followed by deprotection with 1 N HCI. Preliminary biological properties of the probe were evaluated with MCA cells and MCA-tk cells transduced with HSV1-tk reporter gene. In vitro uptake and release-out studies of [{sup 18}F]FHBG were performed, and was analyzed correlation between [{sup 18}F]FHBG uptake ratio according to increasing numeric count of MCA-tk cells and degree of gene expression. MicroPET scan image was obtained with MCA and MCA-tk tumor beating Balb/c-nude mouse model. [{sup 18}F]FHBG was purified by reverse phase semi-HPLC system and collected at around 16-18 min. Radiochemical yield was about 20-25% (corrected for decay), radiochemical purity was > 95% and specific activity was around > 55.5 GBq/ {mu} mol. Specific accumulation of [{sup 18}F]FHBG was observed in HSV1-tk gene transduced MCA-tk cells but not MCA cells, and consecutive 1 hour release-out results showed more than 86% of uptaked [{sup 18}F]FHBG was retained inside of cells. The uptake of [{sup 18}F]FHBG was showed a highly significant linear correlation (R{sup 2} = 0.995) with increasing percentage of MCA-tk numeric cell count. In microPET scan images, remarkable difference of accumulation was observed for the two type of tumors. [{sup 18}F]FHBG appears

  15. Antares: preliminary demonstrator results

    International Nuclear Information System (INIS)

    Kouchner, A.

    2000-05-01

    The ANTARES collaboration is building an undersea neutrino telescope off Toulon (Mediterranean sea) with effective area ∼ 0.1 km 2 . An extensive study of the site properties has been achieved together with software analysis in order to optimize the performance of the detector. Results are summarized here. An instrumented line, linked to shore for first time via an electro-optical cable, has been immersed late 1999. The preliminary results of this demonstrator line are reported. (author)

  16. Graphene–sponges as high-performance low-cost anodes for microbial fuel cells

    KAUST Repository

    Xie, Xing; Yu, Guihua; Liu, Nian; Bao, Zhenan; Criddle, Craig S.; Cui, Yi

    2012-01-01

    A high-performance microbial fuel cell (MFC) anode was constructed from inexpensive materials. Key components were a graphene-sponge (G-S) composite and a stainless-steel (SS) current collector. Anode fabrication is simple, scalable

  17. Improving startup performance with carbon mesh anodes in separator electrode assembly microbial fuel cells

    KAUST Repository

    Zhang, Fang; Xia, Xue; Luo, Yong; Sun, Dan; Call, Douglas F.; Logan, Bruce E.

    2013-01-01

    In a separator electrode assembly microbial fuel cell, oxygen crossover from the cathode inhibits current generation by exoelectrogenic bacteria, resulting in poor reactor startup and performance. To determine the best approach for improving startup

  18. Structural Factors That Affect the Performance of Organic Bulk Heterojunction Solar Cells

    KAUST Repository

    Vandewal, Koen; Himmelberger, Scott; Salleo, Alberto

    2013-01-01

    The performance of polymer:fullerene solar cells is strongly affected by the active layer morphology and polymer microstructure. In this Perspective, we review ongoing research on how structural factors influence the photogeneration and collection

  19. Performance prediction of a proton exchange membrane fuel cell using the ANFIS model

    Energy Technology Data Exchange (ETDEWEB)

    Vural, Yasemin; Ingham, Derek B.; Pourkashanian, Mohamed [Centre for Computational Fluid Dynamics, University of Leeds, Houldsworth Building, LS2 9JT Leeds (United Kingdom)

    2009-11-15

    In this study, the performance (current-voltage curve) prediction of a Proton Exchange Membrane Fuel Cell (PEMFC) is performed for different operational conditions using an Adaptive Neuro-Fuzzy Inference System (ANFIS). First, ANFIS is trained with a set of input and output data. The trained model is then tested with an independent set of experimental data. The trained and tested model is then used to predict the performance curve of the PEMFC under various operational conditions. The model shows very good agreement with the experimental data and this indicates that ANFIS is capable of predicting fuel cell performance (in terms of cell voltage) with a high accuracy in an easy, rapid and cost effective way for the case presented. Finally, the capabilities and the limitations of the model for the application in fuel cells have been discussed. (author)

  20. Impact of salinity on cathode catalyst performance in microbial fuel cells (MFCs)

    KAUST Repository

    Wang, Xi; Cheng, Shaoan; Zhang, Xiaoyuan; Li, Xiao-yan; Logan, Bruce E.

    2011-01-01

    Several alternative cathode catalysts have been proposed for microbial fuel cells (MFCs), but effects of salinity (sodium chloride) on catalyst performance, separate from those of conductivity on internal resistance, have not been previously

  1. Enhancement of device performance of organic solar cells by an interfacial perylene derivative layer

    KAUST Repository

    Kim, Inho; Haverinen, Hanna M.; Li, Jian; Jabbour, Ghassan E.

    2010-01-01

    We report that device performance of organic solar cells consisting of zinc phthalocyanine and fullerene (C60) can be enhanced by insertion of a perylene derivative interfacial layer between fullerene and bathocuproine (BCP) exciton blocking layer

  2. Intratumoral injection of radioactive holmium-166 microspheres in recurrent head and neck squamous cell carcinoma : preliminary results of first use

    NARCIS (Netherlands)

    Bakker, Robbert C; van Es, Robert J J; Rosenberg, Antoine J W P; van Nimwegen, Sebastiaan A; Bastiaannet, Remco; de Jong, Hugo W A M; Nijsen, Johannes F W; Lam, Marnix G E H

    BACKGROUND: Limited treatment options exist for patients with locoregional recurrences of head and neck squamous cell carcinoma (HNSCC). In the palliative setting, a single session, minimally invasive, and relatively safe therapy is desirable. This case series illustrates the feasibility of a direct

  3. Pneumococcal Replicative State in Relation to its Adherence Capacity to A549-cell Line: A Preliminary in vitro Analysis

    Directory of Open Access Journals (Sweden)

    Mohd Desa, M. N.

    2011-01-01

    Full Text Available This study was to compare the replication capacity of pneumococcal isolates (serotypes 1, 7F, 19F and 23F with their adherence pattern to monolayer cells (A549. For standardization purposes, all isolates showed a normal growth curve in both bacteriological (THB + 0.5% yeast extract with and without 2% FBS and cell culture media (RPMI + 2% FBS. In the former media, a shorter lag phase was observed for isolate serotypes 1 and 7F in presence of serum while in the later; growth yield was lower for all isolates with stationary phase approaching OD600 of 0.01 as compared to 1.0 in bacteriological media. In the replicative analysis at different growth phases of the isolates in cell culture media, growth capacity at 3 h post-incubation was frequently twice as that at 1 h, and that at early-log phase was frequently higher than that at mid-log phase at both post-incubation times. Adherence was frequently the least at early-log phase although the isolates were in the most active state of replication to increase the number of pneumococcal cells to adhere. At mid- and late-log phases, pneumococcal adherence was frequently higher although the replication was reduced. This study marks the potential correlation between pneumococcal growth fitness and adherence capacity whereby the later may not be superior during the early growth phase.

  4. Performance and Safety Tests on Samsung 18650 Li-ion Cells with Two Capacities

    Science.gov (United States)

    Deng, Yi; Jeevarajan, Judith; Rehm, Raymond; Bragg, Bobby; Zhang, Wenlin

    2001-01-01

    In order to meet the applications for Space Shuttle in the future, Samsung 18650 cylindrical Li-ion cells with two different capacities have been evaluated. The capacities are 1800 mAh, and 2000 mAh. The studies focused on the performance and safety tests of the cells.

  5. Effect of junction quality on the performance of a silicon solar cell ...

    African Journals Online (AJOL)

    In this work, a modeling study of the effect of the junction quality on the performance of a silicon solar cell is presented. Based on a one dimensional modeling of the solar cell, the continuity equation of excess minority carriers is solved with boundary conditions taking into account the intrinsic junction recombination velocity ...

  6. Preliminary Evidence on the Diagnostic and Molecular Role of Circulating Soluble EGFR in Non-Small Cell Lung Cancer

    Directory of Open Access Journals (Sweden)

    Filippo Lococo

    2015-08-01

    Full Text Available Assessment of biological diagnostic factors providing clinically-relevant information to guide physician decision-making are still needed for diseases with poor outcomes, such as non-small cell lung cancer (NSCLC. Epidermal growth factor receptor (EGFR is a promising molecule in the clinical management of NSCLC. While the EGFR transmembrane form has been extensively investigated in large clinical trials, the soluble, circulating EGFR isoform (sEGFR, which may have a potential clinical use, has rarely been considered. This study investigates the use of sEGFR as a potential diagnostic biomarker for NSCLC and also characterizes the biological function of sEGFR to clarify the molecular mechanisms involved in the course of action of this protein. Plasma sEGFR levels from a heterogeneous cohort of 37 non-advanced NSCLC patients and 54 healthy subjects were analyzed by using an enzyme-linked immunosorbent assay. The biological function of sEGFR was analyzed in vitro using NSCLC cell lines, investigating effects on cell proliferation and migration. We found that plasma sEGFR was significantly decreased in the NSCLC patient group as compared to the control group (median value: 48.6 vs. 55.6 ng/mL respectively; p = 0.0002. Moreover, we demonstrated that sEGFR inhibits growth and migration of NSCLC cells in vitro through molecular mechanisms that included perturbation of EGF/EGFR cell signaling and holoreceptor internalization. These data show that sEGFR is a potential circulating biomarker with a physiological protective role, providing a first approach to the functional role of the soluble isoform of EGFR. However, the impact of these data on daily clinical practice needs to be further investigated in larger prospective studies.

  7. Preliminary Evidence on the Diagnostic and Molecular Role of Circulating Soluble EGFR in Non-Small Cell Lung Cancer

    Science.gov (United States)

    Lococo, Filippo; Paci, Massimiliano; Rapicetta, Cristian; Rossi, Teresa; Sancisi, Valentina; Braglia, Luca; Cavuto, Silvio; Bisagni, Alessandra; Bongarzone, Italia; Noonan, Douglas M.; Albini, Adriana; Maramotti, Sally

    2015-01-01

    Assessment of biological diagnostic factors providing clinically-relevant information to guide physician decision-making are still needed for diseases with poor outcomes, such as non-small cell lung cancer (NSCLC). Epidermal growth factor receptor (EGFR) is a promising molecule in the clinical management of NSCLC. While the EGFR transmembrane form has been extensively investigated in large clinical trials, the soluble, circulating EGFR isoform (sEGFR), which may have a potential clinical use, has rarely been considered. This study investigates the use of sEGFR as a potential diagnostic biomarker for NSCLC and also characterizes the biological function of sEGFR to clarify the molecular mechanisms involved in the course of action of this protein. Plasma sEGFR levels from a heterogeneous cohort of 37 non-advanced NSCLC patients and 54 healthy subjects were analyzed by using an enzyme-linked immunosorbent assay. The biological function of sEGFR was analyzed in vitro using NSCLC cell lines, investigating effects on cell proliferation and migration. We found that plasma sEGFR was significantly decreased in the NSCLC patient group as compared to the control group (median value: 48.6 vs. 55.6 ng/mL respectively; p = 0.0002). Moreover, we demonstrated that sEGFR inhibits growth and migration of NSCLC cells in vitro through molecular mechanisms that included perturbation of EGF/EGFR cell signaling and holoreceptor internalization. These data show that sEGFR is a potential circulating biomarker with a physiological protective role, providing a first approach to the functional role of the soluble isoform of EGFR. However, the impact of these data on daily clinical practice needs to be further investigated in larger prospective studies. PMID:26295387

  8. Effects of dimethyl ether on the performance characteristics of a direct methanol fuel cell

    International Nuclear Information System (INIS)

    Seo, Sang Hern; Lee, Chang Sik

    2013-01-01

    Highlights: • Activation loss is significantly reduced in fuel cell with DME-methanol. • DME crossover through the membrane reduces. • The open circuit voltage of DME-methanol the fuel cell increases. • The overall efficiency of the mixed fuel cell is higher than that of DMFC. - Abstract: The objective of this study was to determine the effects of dimethyl ether (DME) on the performance characteristics of a direct methanol fuel cell. Impedance and crossover experiments were performed in order to investigate the performance losses such as ohmic loss, activation loss and crossover loss accurately. The DME was pressurized to 5 bar to supply with liquid phase was and blended with an aqueous methanol solution. In this experiment, the membrane electrode assembly (MEA) was composed of Nafion 115, anode catalyst loaded Pt–Ru and cathode catalyst loaded Pt-Black. Experimental results showed that fuel cells with DME-methanol enhanced performance when compared to fuel cells with methanol only. Such performance enhancement was due to a decrease in activation losses by DME oxidation reactions. As the DME crossover through the membrane was reduced, the open circuit voltage (OCV) of the fuel cell increased. Other output characteristics are also discussed

  9. Interface Engineering of Organic Schottky Barrier Solar Cells and Its Application in Enhancing Performances of Planar Heterojunction Solar Cells

    OpenAIRE

    Fangming Jin; Zisheng Su; Bei Chu; Pengfei Cheng; Junbo Wang; Haifeng Zhao; Yuan Gao; Xingwu Yan; Wenlian Li

    2016-01-01

    In this work, we describe the performance of organic Schottky barrier solar cells with the structure of ITO/molybdenum oxide (MoOx)/boron subphthalocyanine chloride (SubPc)/bathophenanthroline (BPhen)/Al. The SubPc-based Schottky barrier solar cells exhibited a short-circuit current density (Jsc) of 2.59?mA/cm2, an open-circuit voltage (Voc) of 1.06?V, and a power conversion efficiency (PCE) of 0.82% under simulated AM1.5?G solar illumination at 100?mW/cm2. Device performance was substantiall...

  10. Performance enhancement of thin film silicon solar cells based on distributed Bragg reflector & diffraction grating

    Directory of Open Access Journals (Sweden)

    R. S. Dubey

    2014-12-01

    Full Text Available The influence of various designing parameters were investigated and explored for high performance solar cells. Single layer grating based solar cell of 50 μm thickness gives maximum efficiency up to 24 % whereas same efficiency is achieved with the use of three bilayers grating based solar cell of 30 μm thickness. Remarkably, bilayer grating based solar cell design not only gives broadband absorption but also enhancement in efficiency with reduced cell thickness requirement. This absorption enhancement is attributed to the high reflection and diffraction from DBR and grating respectively. The obtained short-circuit current were 29.6, 32.9, 34.6 and 36.05 mA/cm2 of 5, 10, 20 and 30 μm cell thicknesses respectively. These presented designing efforts would be helpful to design and realize new generation of solar cells.

  11. State performance in pluripotent and adult stem cell research, 2009-2016.

    Science.gov (United States)

    Surani, Sana H; Levine, Aaron D

    2018-04-01

    To examine how the geographic distribution of pluripotent and adult stem cell research publications within the USA differs from other areas of biomedical research. Publication count data for pluripotent stem cell research, adult stem cell research and a comparison group representative of biomedical research more broadly were collected and analyzed for each US state from 2009 to 2016. The distribution of pluripotent stem cell research differed from the other fields with overperformance in pluripotent stem cell research observed in California, as well as Wisconsin, Massachusetts, Maryland and Connecticut. Our analysis suggests that permissive state stem cell policy may be one of the several factors contributing to strong state performance in pluripotent stem cell research.

  12. In-cell facility for performing mechanical-property tests on irradiated cladding

    International Nuclear Information System (INIS)

    Yaggee, F.L.; Haglund, R.C.; Mattas, R.F.

    1978-11-01

    A new facility was developed for testing cladding sections of LWR fuel rods. This facility and the accompanying test procedures have improved the level of in-cell mechanical-testing capabilities, making them comparable to existing capabilities for unirradiated cladding. The new facility is currently being used to study the susceptibility of irradiated Zircaloy cladding from LWR fuel rods to iodine stress-corrosion cracking. Preliminary testing results indicate a systematic effect of temperature, stress and irradiation on the susceptibility of annealed and stress-relieved Zircaloy-2. Experimental data obtained to date are being used to develop a stress-corrosion cracking model for LWR fuel rod failure. SEM examination of the undisturbed fracture surface of specimens that failed by pinhole leakage provides useful information on crack propagation and morphology

  13. Relating Direct Methanol Fuel Cell Performance to Measurements in a Liquid Half Cell

    DEFF Research Database (Denmark)

    Pedersen, Christoffer Mølleskov; Tynelius, Oskar; Lund-Olesen, Torsten

    2015-01-01

    Direct methanol fuel cells (DMFC) could act as a replacement for batteries in low power electronics. For instance, micro—DMFC’s could be used to power hearing instruments[1]. The power output of a DMFC is limited by the sluggish kinetics of both the methanol oxidation reaction (MOR) on the anode ...... Cells Bull. 2012 (2012) 12–16. doi:10.1016/S1464-2859(12)70367-X....

  14. Analysis of performance losses of direct ethanol fuel cells with the aid of a reference electrode

    Science.gov (United States)

    Li, Guangchun; Pickup, Peter G.

    The performances of direct ethanol fuel cells with different anode catalysts, different ethanol concentrations, and at different operating temperatures have been studied. The performance losses of the cell have been separated into individual electrode performance losses with the aid of a reference electrode, ethanol crossover has been quantified, and CO 2 and acetic acid production have been measured by titration. It has been shown that the cell performance strongly depends on the anode catalyst, ethanol concentration, and operating temperature. It was found that the cathode and anode exhibit different dependences on ethanol concentration and operating temperature. The performance of the cathode is very sensitive to the rate of ethanol crossover. Product analysis provides insights into the mechanisms of electro-oxidation of ethanol.

  15. Analysis of performance losses of direct ethanol fuel cells with the aid of a reference electrode

    Energy Technology Data Exchange (ETDEWEB)

    Li, Guangchun; Pickup, Peter G. [Department of Chemistry, Memorial University of Newfoundland, Elizabeth Avenue, St. John' s, Newfoundland (Canada A 1B 3X7)

    2006-10-20

    The performances of direct ethanol fuel cells with different anode catalysts, different ethanol concentrations, and at different operating temperatures have been studied. The performance losses of the cell have been separated into individual electrode performance losses with the aid of a reference electrode, ethanol crossover has been quantified, and CO{sub 2} and acetic acid production have been measured by titration. It has been shown that the cell performance strongly depends on the anode catalyst, ethanol concentration, and operating temperature. It was found that the cathode and anode exhibit different dependences on ethanol concentration and operating temperature. The performance of the cathode is very sensitive to the rate of ethanol crossover. Product analysis provides insights into the mechanisms of electro-oxidation of ethanol. (author)

  16. Preliminary observations on differences in the Raman spectra of cancerous and noncancerous cells and connective tissue of human skin

    Science.gov (United States)

    Short, Michael A.; Lui, Harvey; McLean, David I.; Zeng, Haishan; Alajlan, Abdulmajeed; Chen, Michael X.

    2005-04-01

    A less invasive method of reliably detecting skin cancers is required. Raman spectroscopy is just one of several spectroscopic methods that look promising, but are not yet sufficiently reliable. More information is needed on how and why the Raman spectra of cancerous skin tissue is different from its normal counterpart. We have used confocal micro-Raman spectroscopy with a spatial resolution of about a micron to obtain spectra of unstained thin sections of human skin. We found that there were clear differences in the Raman spectra between cancerous and non-cancerous tissue both in cells and in the connective tissue. The DNA contribution to the spectra was generally stronger in malignant cells than normal ones. In regions of the dermis far away from the tumor one obtains the usual collagen spectra of normal skin, but adjacent to the tumor the spectra no longer appeared to be those of native collagen.

  17. [Preliminary study of constructing tissue-engineered cartilage with the endoskeletal scaffold of HDPE by bone marrow stromal cells].

    Science.gov (United States)

    Zhu, Lie; Jiang, Hua; Zhou, Guang-Dong; Wu, Yu-Jia; Luo, Xu-Song

    2008-09-01

    To explore the feasibility of using a nonreactive, permanent endoskeletal scaffold to create the prothesis in special shape which is covered with tissue-engineered cartilage. Porcine BMSCs and articular chondrocytes were isolated and expanded respectively in vitro. Porcine BMSC of passage 1 in the concentration of 10 x 10(7)/ml were seeded onto a cylinder-shaped PGA (1 mm in thickness)/Medpor (3mm in diameter and 5mm in highness) scaffold as the experimental group. After the cell-scaffold constructs were cultured for 5 days, the primary medium, high-glucose DMEM medium with 10% fetal bovine serum (FBS), was replaced by chondrogenically inductive medium for 4 weeks. BMSCs and chondrocytes of the same concentration were seeded respectively onto the scaffold as the negative control group and the positive control group. After cultured in vitro for 4 weeks, the cell-scaffolds construct were implanted into subcutaneous pockets on the back of nude mice. Four and eight weeks later, the formed cartilage prosthesis were harvested and then evaluated by gross view, histology, immunohistochemistry and glycosamino-glycan (GAG) content. Cells in all groups had fine adhesion to the scaffold and could secrete extracellular matrix. All specimens in experimental group and positive control group formed mature cartilage with collagen II expression.The mature catrtilage wraped HDPE compactly and grown into the gap of HDPE. Mature lacuna structures and metachromatic matrices were also observed in these specimens. GAG contents in experimental group were (5.13 +/- 0.32) mg/g (4 weeks), (5.37 +/- 0.12) mg/g (8 weeks). In contrast, specimens in BMSC group showed mainly fibrous tissue. It indicates that it is feasible to create special shaped tissue-engineering cartilage with the permanent internal support using BMSCs as seed cell.

  18. Preliminary results of Digital Pulse Shape Acquisition from Chimera

    Energy Technology Data Exchange (ETDEWEB)

    Alderighi, D.M.; Sechi, G. [INFN Milano and IASF, CNR, Milano (France); Anzalone, A.; Cavallaro, S.; Giustolisi, F.; Laguidara, E.; Lanzalone, G.; Porto, F. [Catania Univ., LNS and Dipartimento di Fisica (France); Bassini, R.; Boiano, C.; Guazzoni, P.; Russo, S.; Sassi, M.; Zetta, L. [Milano Univ., INFN and Dipartimento di Fisica (Italy); Cardella, G.; Defilippo, S.E.; Lanzano, G.; Paganod, A.; Papa, M.; Pirrone, S.; Politi, G. [Catania Univ., INFN and Dipartimento di Fisica (Italy); Geraci, E. [Bologna Univ., INFN and Dipartimento di Fisica (Italy)

    2003-07-01

    A 100 MS/s 14-bit Sampling Analog-to-Digital converter has been used to perform digital pulse-shape acquisition of signals collected from CHIMERA telescopes. The signals from a typical CHIMERA detection cell have been collected using both a standard CHIMERA electronic chain up to the amplifier, and a very simple analog front end, basically reduced to the preamplifier. The preliminary on-beam results are presented. (authors)

  19. Preliminary results of Digital Pulse Shape Acquisition from Chimera

    International Nuclear Information System (INIS)

    Alderighi, D.M.; Sechi, G.; Anzalone, A.; Cavallaro, S.; Giustolisi, F.; Laguidara, E.; Lanzalone, G.; Porto, F.; Bassini, R.; Boiano, C.; Guazzoni, P.; Russo, S.; Sassi, M.; Zetta, L.; Cardella, G.; Defilippo, S.E.; Lanzano, G.; Paganod, A.; Papa, M.; Pirrone, S.; Politi, G.; Geraci, E.

    2003-01-01

    A 100 MS/s 14-bit Sampling Analog-to-Digital converter has been used to perform digital pulse-shape acquisition of signals collected from CHIMERA telescopes. The signals from a typical CHIMERA detection cell have been collected using both a standard CHIMERA electronic chain up to the amplifier, and a very simple analog front end, basically reduced to the preamplifier. The preliminary on-beam results are presented. (authors)

  20. A preliminary investigation into the impact of a pesticide combination on human neuronal and glial cell lines in vitro.

    Directory of Open Access Journals (Sweden)

    Michael D Coleman

    Full Text Available Many pesticides are used increasingly in combinations during crop protection and their stability ensures the presence of such combinations in foodstuffs. The effects of three fungicides, pyrimethanil, cyprodinil and fludioxonil, were investigated together and separately on U251 and SH-SY5Y cells, which can be representative of human CNS glial and neuronal cells respectively. Over 48h, all three agents showed significant reductions in cellular ATP, at concentrations that were more than tenfold lower than those which significantly impaired cellular viability. The effects on energy metabolism were reflected in their marked toxic effects on mitochondrial membrane potential. In addition, evidence of oxidative stress was seen in terms of a fall in cellular thiols coupled with increases in the expression of enzymes associated with reactive species formation, such as GSH peroxidase and superoxide dismutase. The glial cell line showed significant responsiveness to the toxin challenge in terms of changes in antioxidant gene expression, although the neuronal SH-SY5Y line exhibited greater vulnerability to toxicity, which was reflected in significant increases in caspase-3 expression, which is indicative of the initiation of apoptosis. Cyprodinil was the most toxic agent individually, although oxidative stress-related enzyme gene expression increases appeared to demonstrate some degree of synergy in the presence of the combination of agents. This report suggests that the impact of some pesticides, both individually and in combinations, merits further study in terms of their impact on human cellular health.

  1. Performance of (CoPC)n catalyst in active lithium-thionyl chloride cells

    Science.gov (United States)

    Shah, Pinakin M.

    1990-01-01

    An experimental study was conducted with anode limited D size cells to characterize the performance of an active lithium-thionyl chloride (Li/SOCl2) system using the polymeric cobalt phthalocyanine, (CoPC)n, catalyst in carbon cathodes. The author describes the results of this experiment with respect to initial voltage delays, operating voltages, and capacities. The effectiveness of the preconditioning methods evolved to alleviate passivation effects on storage are also discussed. The results clearly demonstrated the superior high rate capability of cells with the catalyst. The catalyst did not adversely impact the performance of cells after active storage for up to 6 months, while retaining its beneficial influences.

  2. Analysis and performance of adjacent-cell preconditioners for accelerating multidimensional transport calculations

    International Nuclear Information System (INIS)

    Azmy, Y.Y.

    1996-01-01

    The formal development of the Adjacent-cell Preconditioner (AP) and its implementation in the TORT code are briefly reviewed. Based on earlier experience with diffusion type acceleration, and excellent results in slab geometry the reciprocal averaging formula is used to mix the preconditioner elements across material and mesh discontinuities. Numerical testing of the method employing the Burre Suite of Test Problems (BSTeP), a collection of 144 cases covering a wide range in parameter space, using AP, Partial Current Rebalance (PCR), and TWODANT's Diffusion Synthetic Acceleration (DSA) is presented. While AP outperforms the other two methods for the majority of the cases included in BSTeP it consumes many more iterations than can be explained by spectral analysis of the homogeneous model problem in cases with sharp material discontinuity. In order to verify this undesirable behavior and explore potential remedies a model problem, the Periodic Horizontal Interface (PHI), is developed that permits discontinuity of nuclear properties and cell height across the interface. Fourier mode decomposition is applied to AP with the reciprocal averaging mixing formula for the PHI configuration and shown to possess a spectral radius that approaches unity as the material discontinuity gets larger. The question of whether an unconditionally stable AP exists for PHI is tackled and preliminary indications are negative. Novel preconditioners that have nontraditional cell-coupling schemes that remain stable in these regimes may have to be sought

  3. Dye-sensitized solar cells and solar module using polymer electrolytes: Stability and performance investigations

    Directory of Open Access Journals (Sweden)

    Jilian Nei de Freitas

    2006-01-01

    Full Text Available We present recent results on solid-state dye-sensitized solar cell research using a polymer electrolyte based on a poly(ethylene oxide derivative. The stability and performance of the devices have been improved by a modification in the method of assembly of the cells and by the addition of plasticizers in the electrolyte. After 30 days of solar irradiation (100 mW cm-2 no changes in the cell's efficiency were observed using this new method. The effect of the active area size on cell performance and the first results obtained for the first solar module composed of 4.5 cm2 solid-state solar cells are also presented.

  4. A review on the performance and modelling of proton exchange membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Boucetta, A., E-mail: abirboucetta@yahoo.fr; Ghodbane, H., E-mail: h.ghodbane@mselab.org; Bahri, M., E-mail: m.bahri@mselab.org [Department of Electrical Engineering, MSE Laboratory, Mohamed khider Biskra University (Algeria); Ayad, M. Y., E-mail: ayadmy@gmail.com [R& D, Industrial Hybrid Vehicle Applications (France)

    2016-07-25

    Proton Exchange Membrane Fuel Cells (PEMFC), are energy efficient and environmentally friendly alternative to conventional energy conversion for various applications in stationary power plants, portable power device and transportation. PEM fuel cells provide low operating temperature and high-energy efficiency with near zero emission. A PEM fuel cell is a multiple distinct parts device and a series of mass, energy, transport through gas channels, electric current transport through membrane electrode assembly and electrochemical reactions at the triple-phase boundaries. These processes play a decisive role in determining the performance of the Fuel cell, so that studies on the phenomena of gas flows and the performance modelling are made deeply. This paper gives a comprehensive overview of the state of the art on the Study of the phenomena of gas flow and performance modelling of PEMFC.

  5. Modeling electrochemical performance in large scale proton exchange membrane fuel cell stacks

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J H [Los Alamos National Lab., NM (United States); Lalk, T R [Texas A and M Univ., College Station, TX (United States). Dept. of Mechanical Engineering; Appleby, A J [Center for Electrochemical Studies and Hydrogen Research, Texas Engineering Experimentation Station, Texas A and M Univ., College Station, TX (United States)

    1998-02-01

    The processes, losses, and electrical characteristics of a Membrane-Electrode Assembly (MEA) of a Proton Exchange Membrane Fuel Cell (PEMFC) are described. In addition, a technique for numerically modeling the electrochemical performance of a MEA, developed specifically to be implemented as part of a numerical model of a complete fuel cell stack, is presented. The technique of calculating electrochemical performance was demonstrated by modeling the MEA of a 350 cm{sup 2}, 125 cell PEMFC and combining it with a dynamic fuel cell stack model developed by the authors. Results from the demonstration that pertain to the MEA sub-model are given and described. These include plots of the temperature, pressure, humidity, and oxygen partial pressure distributions for the middle MEA of the modeled stack as well as the corresponding current produced by that MEA. The demonstration showed that models developed using this technique produce results that are reasonable when compared to established performance expectations and experimental results. (orig.)

  6. Improved performance in GaInNAs solar cells by hydrogen passivation

    International Nuclear Information System (INIS)

    Fukuda, M.; Whiteside, V. R.; Keay, J. C.; Meleco, A.; Sellers, I. R.; Hossain, K.; Golding, T. D.; Leroux, M.; Al Khalfioui, M.

    2015-01-01

    The effect of UV-activated hydrogenation on the performance of GaInNAs solar cells is presented. A proof-of-principle investigation was performed on non-optimum GaInNAs cells, which allowed a clearer investigation of the role of passivation on the intrinsic nitrogen-related defects in these materials. Upon optimized hydrogenation of GaInNAs, a significant reduction in the presence of defect and impurity based luminescence is observed as compared to that of unpassivated reference material. This improvement in the optical properties is directly transferred to an improved performance in solar cell operation, with a more than two-fold improvement in the external quantum efficiency and short circuit current density upon hydrogenation. Temperature dependent photovoltaic measurements indicate a strong contribution of carrier localization and detrapping processes, with non-radiative processes dominating in the reference materials, and evidence for additional strong radiative losses in the hydrogenated solar cells

  7. The prognostic effect of subpleural lesions in early stage non-small cell lung cancer: preliminary report

    International Nuclear Information System (INIS)

    Lee, Ho Jun; Lee, Hyung Sik; Hur, Won Joo; Lee, Ki Nam; Choi, Pill Jo

    1998-01-01

    We retrospectively analyzed the impact of subpleural lesions of early stage non-small cell lung cancer on the patterns of failure to support selection of postoperative adjuvant therapy. The study included 91 patients who underwent surgery for early stage non-small cell lung cancer at Donga University hospital from Dec 1990 to Sep 1996. Twenty five patients were excluded due to postoperative mortality (four patients, 4.4%) and stage III (21 patients). Of 66 patients, 22 patients were subpleural lesions (15 patients in stage I, and seven patients in stage II). Postoperative adjuvant radiation therapy was given to seven patients with T2N1 disease. The median follow-up duration was 29.5 months (range; 8-84 months). The overall survival rate was 69.5% at 3 years. For all patients who presented with (22 patients) and without (44 patients) subpleural lesions, 3-year overall survival rates were 35.5% and 84.6%, respectively (p=0.0017). For stage I patients who presented with (15 patients) and without (29 patients) subpleural lesions, 3-year overall survival rates were 33.1% and 92.3%, respectively (p=0.001). For stage II patients who presented with (7 patients) and without (15 patients) subpleural lesions, 3-year overall survival rates were 53.3% and 45.7%, respectively (p=0.911). For patients with T2NO disease (34 patients) who presented with (11 patients) and without (23 patients) subpleural lesions, 3-year overall survival rates were 27.3% and 90.3%,respectively (p=0.009).These observations suggest that the subpleural lesion play an important role as a prognostic factor for early stage non-small cell lung cancer. Especially for T2NO disease, patients with subpleural lesions showed significantly lower survival rate than those without that

  8. MORPHOLOGICAL CHARACTERISTIC OF SPERMATOGONIA AND TESTES DISSOCIATION : A Preliminary Study for the Germ Cell Transplantation in Giant Gouramy (Osphronemus gouramy

    Directory of Open Access Journals (Sweden)

    Irma Andriani

    2010-12-01

    Full Text Available The recent study were attempting to develop spermatogonial germ cell transplantation as a tool to preserve and propagate male germ-plasm from endangered fish species, as well as to produce surrogate broodstock of commercially valuable fish. Spermatogonia identification and testes dissociation were the first necessary steps to obtain highly amount and viable population of spermatogonia as donor cells for transplantation. Using giant gouramy testes as a model, spermatogonia was histological characterized and two methods of testes dissociations were compared (i.e. medium A contained 0.5% trypsin in PBS and medium B contained 0.5% trypsin and DNase 10 IU/μL in PBS complemented with CaCl2, Hepes and FCS. Optimal incubation times (1, 2, 3, 4 and 5 hours in dissociation medium were also determined. Freshly isolated testes of immature giant gouramy were minced in dissociation medium and then incubated to get monodisperce cell suspension. Parameters observed were number and viability of spermatogonia (ø > 10 μm. The viability was analyzed using trypan blue exclusion dye. The results showed that the average number of spermatogonia observed in medium B was higher than in medium A (P0.05. The viability of spermatogonia decreased by the increasing duration time of dissociation. The viability of spermatogonia started to decrease significantly in 2 hours incubation time in medium A and 4 hours incubation time in medium B (P<0.05. In conclusion, application of dissociation medium B yielded higher number of viable spermatogonia than dissociation medium A.

  9. Factors Influencing Academic Performance of Students Enrolled in a Lower Division Cell Biology Core Course

    Science.gov (United States)

    Soto, Julio G.; Anand, Sulekha

    2009-01-01

    Students' performance in two semesters of our Cell Biology course was examined for this study. Teaching strategies, behaviors, and pre-course variables were analyzed with respect to students' performance. Pre-semester and post-semester surveys were administered to ascertain students' perceptions about class difficulty, amount of study and effort…

  10. School Performance and Disease Interference in Adolescents with Sickle Cell Disease

    Science.gov (United States)

    Crosby, Lori E.; Joffe, Naomi E.; Irwin, Mary Kay; Strong, Heather; Peugh, James; Shook, Lisa; Kalinyak, Karen A.; Mitchell, Monica J.

    2015-01-01

    Sickle cell disease (SCD) results in neuropsychological complications that place adolescents at higher risk for limited educational achievement. A first step to developing effective educational interventions is to understand the impact of SCD on school performance. The current study assessed perceptions of school performance, SCD interference and…

  11. A preliminary investigation into the extent of increased radioresistance or hyper-radiosensitivity in cells of hamster cell lines known to be deficient in DNA repair

    International Nuclear Information System (INIS)

    Skov, K.; Marples, B.; Matthews, J.B.; Zhou, H.; Joiner, M.C.

    1994-01-01

    The response to low doses of X rays was assessed in cells of three hamster cell lines which are defective in DNA repair and was compared with their parental lines. Cells of the V79-derived double-strand break repair-deficient line XR-V15B showed no radioresistance in the 0.5-Gy range compared with the V79B wild type, but instead showed an exponential response. Cells of the single-strand break repair-deficient line EM9 showed hyper-radiosensitivity and exhibited increased radioresistance. Most interestingly, cells of the UV-20 cell line appeared to respond exponentially, as a continuation of the hyper-radiosensitive portion of the curve, with no evidence of increased radioresistance. This line is defective in an incision step of excision repair and is sensitive to crosslinking agents. Further studies are warranted to address the possible role of single- and double-strand break repair and excision repair in hyper-radiosensitivity and increased radioresistance. 24 refs., 4 figs

  12. Insulin-producing Cells from Adult Human Bone Marrow Mesenchymal Stromal Cells Could Control Chemically Induced Diabetes in Dogs: A Preliminary Study.

    Science.gov (United States)

    Gabr, Mahmoud M; Zakaria, Mahmoud M; Refaie, Ayman F; Ismail, Amani M; Khater, Sherry M; Ashamallah, Sylvia A; Azzam, Maha M; Ghoneim, Mohamed A

    2018-01-01

    Ten mongrel dogs were used in this study. Diabetes was chemically induced in 7 dogs, and 3 dogs served as normal controls. For each diabetic dog, 5 million human bone marrow-derived mesenchymal stem cells/kg were differentiated to form insulin-producing cells using a trichostatin-based protocol. Cells were then loaded in 2 TheraCyte capsules which were transplanted under the rectus sheath. One dog died 4 d postoperatively from pneumonia. Six dogs were followed up with for 6 to 18 mo. Euglycemia was achieved in 4 dogs. Their glucose tolerance curves exhibited a normal pattern demonstrating that the encapsulated cells were glucose sensitive and insulin responsive. In the remaining 2 dogs, the fasting blood sugar levels were reduced but did not reach normal values. The sera of all transplanted dogs contained human insulin and C-peptide with a negligible amount of canine insulin. Removal of the transplanted capsules was followed by prompt return of diabetes. Intracytoplasmic insulin granules were seen by immunofluorescence in cells from the harvested capsules. Furthermore, all pancreatic endocrine genes were expressed. This study demonstrated that the TheraCyte capsule or a similar device can provide adequate immunoisolation, an important issue when stem cells are considered for the treatment of type 1 diabetes mellitus.

  13. Performance of PEM Liquid-Feed Direct Methanol-Air Fuel Cells

    Science.gov (United States)

    Narayanan, S. R.

    1995-01-01

    A direct methanol-air fuel cell operating at near atmospheric pressure, low-flow rate air, and at temperatures close to 60oC would tremendously enlarge the scope of potential applications. While earlier studies have reported performance with oxygen, the present study focuses on characterizing the performance of a PEM liquid feed direct methanol-air cell consisting of components developed in house. These cells employ Pt-Ru catalyst in the anode, Pt at the cathode and Nafion 117 as the PEM. The effect of pressure, flow rate of air and temperature on cell performance has been studied. With air, the performance level is as high as 0.437 V at 300 mA/cm2 (90oC, 20 psig, and excess air flow) has been attained. Even more significant is the performance level at 60oC, 1 atm and low flow rates of air (3-5 times stoichiometric), which is 0.4 V at 150 mA/cm2. Individual electrode potentials for the methanol and air electrode have been separated and analyzed. Fuel crossover rates and the impact of fuel crossover on the performance of the air electrode have also been measured. The study identifies issues specific to the methanol-air fuel cell and provides a basis for improvement strategies.

  14. Preliminary results of cold fusion studies using a five module high current electrolytic cell (Paper No. A2)

    International Nuclear Information System (INIS)

    Nayar, M.G.; Mitra, S.K.; Raghunathan, P.; Krishnan, M.S.; Malhotra, S.K.; Gaonkar, D.G.; Sikka, S.K.; Shyam, A.; Chitra, V.

    1989-01-01

    A high current modular palladium-nickel electrolytic cell was designed and operated to observe cold fusion reactions. The cathode was made up of palladium (25 per cent)-silver and the anode was made up of porous nickel. Using NaOD in D 2 O (20 per cent) as an electrolyte, the electrolyser was operated continuously at a current of 60 to 65 amps and applied voltage of ∼ 12.5V. The deuterium and oxygen gases produced were carried out of the cell to a recombination unit consisting of burner and condenser. The resultant heavy water was recycled back to the electrolyser. Measurement of the neutron output and tritium content of the electrolyte during and after electrolysis conclusively showed occurrence of cold fusion reactions. Gross neutron to tritium yield ratio was observed to be ∼ 10 -9 which should be taken as a lower limit, because a considerable quantity of tritium carried away by the gas stream could not recovered and taken into account. (M.G.B.). 2 tabs., 2 figs

  15. Changes of dendritic cells and fractalkine in type 2 diabetic patients with unstable angina pectoris: a preliminary report

    Directory of Open Access Journals (Sweden)

    Qian Juying

    2011-06-01

    Full Text Available Abstract Background It has been shown that dendritic cells (DCs and fractalkine play a role in accelerating progression of the inflamed atherosclerotic lesions and plaque rupture. We evaluated the numbers and functional changes of DCs and its subsets in human type 2 diabetes with or without unstable angina pectoris (UAP. Methods The study population consisted of 39 diabetic patients (DM:18 without CAD; DM + UAP: 21 with UAP, 18 non-diabetic UAP patients (UAP, and 15 healthy control (Normal. Peripheral blood DCs and its subsets were measured by three color flow cytometry. Serum levels of fractalkine, IL-12, and IFN-α were also measured. The functional status of the monocyte-derived DCs was analyzed by flow cytometry and allogeneic mixed T lymphocytes reaction. Results The percent and absolute numbers of DCs and mDC within the total leukocyte population was similar for Normal and DM, while significantly lower in DM + UAP. pDC numbers were not significantly altered. Serum fractalkine in DM + UAP was highest among the four groups (p = 0.04 vs. UAP, p = 0.0003 vs. DM, p p = 0.01 level. Compared with DM and UAP, the costimulatory molecules CD86 and proliferation of T cells stimulated by DCs were significantly increased in DM + UAP group. Conclusions Our study suggested that increases in the fractalkine level and the number and functional changes of blood DCs might contribute to diabetic coronary atherosclerosis and plaque destabilization.

  16. Preliminary study of the influence of red blood cells morphometry on the species determinism of domestic animals

    Directory of Open Access Journals (Sweden)

    Nezar Adili

    2014-04-01

    Full Text Available Aim: This survey was realized on cattle, sheep, goats, horses, and dogs, in order to study the influence of three morphometric parameters: the diameter, the circumference and the surface of red blood cells on the determinism of these species. Materials and Methods: For each species, blood samples were taken from 15 adult female by jugular venipuncture with confection of blood smears on microscope slides immediately after blood collection and stained according to the method of May-Gründwald Giemsa. Morphometric study was realized using the software OPTIKA Pro Vision. To better describe the results, the statistical analysis was assessed by using the descriptive Boxplots test, ANOVA, and the Student's t-test. Results: The morphometric parameters of red blood cells are biggest in dogs followed by horses, cattle, and sheep, while goats have the lowest ones. Conclusion: This investigation allowed us to show that from a drop of blood we can have an idea about the animal species taking into account the diameter, the circumference, and the surface of erythrocytes.

  17. Effects of coal-derived trace species on the performance of molten carbonate fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Pigeaud, A.

    1991-10-01

    The overall objective of the present study was to determine in detail the interaction effects of 10 simultaneously present, coal-gas contaminants, both on each other and on components of the Carbonate Fuel Cell. The primary goal was to assess underlying chemistries and reaction mechanisms which may cause decay in fuel cell performance or endurance as a result of both physics-chemical and/or mechanical interactions with the cell components and internal fuel cell parts. It was found, both from theory and cell test evidence, that trace contaminant interactions may occur with: Fuel-cell Electrodes (e.g., in this study with the Ni-anode), Lithium/Potassium Carbonate Electrolyte, Nickel and SS-Hardware, and by Mechanical Obstruction of Gas Flow in the Anode Plenum.

  18. Modeling and performance analysis dataset of a CIGS solar cell with ZnS buffer layer

    Directory of Open Access Journals (Sweden)

    Md. Billal Hosen

    2017-10-01

    Full Text Available This article represents the baseline data of the several semiconductor materials used in the model of a CIGS thin film solar cell with an inclusion of ZnS buffer layer. As well, input parameters, contact layer data and operating conditions for CIGS solar cell simulation with ZnS buffer layer have been described. The schematic diagram of photovoltaic solar cell has been depicted. Moreover, the most important performance measurement graph, J-V characteristic curve, resulting from CIGS solar cell simulation has been analyzed to estimate the optimum values of fill factor and cell efficiency. These optimum results have been obtained from the open circuit voltage, short circuit current density, and the maximum points of voltage and current density generated from the cell.

  19. MVP Chemotherapy and Hyperfractionated Radiotherapy for Stage III Unresectable Non-Small Cell Lung Cancer - Randomized for maintenance Chemotherapy vs. Observation; Preliminary Report-

    International Nuclear Information System (INIS)

    Choi, Euk Kyung; Chang, Hye Sook; Suh, Cheol Won

    1991-01-01

    To evaluate the effect of MVP chemotherapy and hyperfractionated radiotherapy in Stage III unresectable non small cell lung cancer (NSCLC), authors have conducted a prospective randomized study since January 1991. Stage IIIa or IIIb unresectable NSCLC patients were treated with hyperfractionated radiotherapy (120 cGy/fx BID) up to 6500 cGY following 3 cycles of induction MVP (Mitomycin C 6 mg/m 2 , vinblastine 6 mg/m 2 , Cisplatin 60 mg/m 2 ) and randomized for either observation or 3 cycles of maintenance MVP chemotherapy. Until August 1991, 18 patients were registered to this study. 4 cases were stage IIIa and 14 were stage IIIb. Among 18 cases 2 were lost after 2 cycles of chemotherapy, and 16 were analyzed for this preliminary report. The response rate of induction chemotherapy was 62.5%; partial response, 50% and minimal response, 12.5%. Residual tumor of the one partial responder was completely disappeared after radiotherapy. Among 6 cases who were progressed during induction chemotherapy, 4 of them were also progressed after radiotherapy. All patients were tolerated BID radiotherapy without definite increase of acute complications, compared with conventional radiotherapy group. But at the time of this report, one patient expired in two month after the completion of the radiotherapy because of treatment related complication. Although the longer follow up is needed, authors are encouraged with higher response rate and acceptable toxicity of this treatment. Authors believe that this study is worthwhile to continue

  20. Dioxin-like (PCB 126) and non dioxin-like (PCB 153) action on DNA damage and apoptosis in granulosa cells. Preliminary data

    Energy Technology Data Exchange (ETDEWEB)

    Gregoraszczuk, E.L.; Wojtowicz, A. [Lab. of Physiology and Toxicology of Reproduction, Inst. of Zoology, Jagiellonian Univ., Krakow (Poland); Kapiszewska, M.; Magnowska, Z. [Dept. of General Biochemistry, Jagiellonian Univ., Krakow (Poland)

    2004-09-15

    Introduction Approximately 60-90% of all cancer cases are now generally believed to be due to environmental factors, to which humans are exposed by taking food, and water or inhaling air. These chemicals, including polycyclic aromatic hydrocarbons (PAHs), can be subdivided into different classes. TCDD was classified as group (documented carcinogen in humans) Benzo [a] pyrene and benzo [a] anthracene were included into group 2A (probably carcinogen in humans). PCB is not mentioned in this list. The International Agency for Research on Cancer (IARC) maintains a register of human carcinogens and suspected human carcinogens. The capacity of PCBs to induce DNA strand breaks has been studied to a lesser degree and is quite controversial. DNA strand breaks are the potentially mutagenic lesions that have been proposed as a genotoxicity biomarker for the biomonitoring of environmental pollutants. The mutations induced by these lesions in pollutant-exposed populations are believed to be induced by chemical carcinogens. The formation of PCB adducts has been demonstrated and measured in vitro and in vivo 3. The capacity of PCBs to form DNA adducts depends on their metabolic rate, which is determined by the degree of chlorination. The aim of the presented preliminary data was to evaluate the follicular stage-specific action of PCB 126 and PCB 153 on DNA damage and apoptosis in granulosa cells.

  1. Plasma glial cell line-derived neurotrophic factor in patients with major depressive disorder: a preliminary study.

    Science.gov (United States)

    Lee, Bun-Hee; Hong, Jin-Pyo; Hwang, Jung-A; Na, Kyoung-Sae; Kim, Won-Joong; Trigo, Jose; Kim, Yong-Ku

    2016-02-01

    Some clinical studies have reported reduced peripheral glial cell line-derived neurotrophic factor (GDNF) level in elderly patients with major depressive disorder (MDD). We verified whether a reduction in plasma GDNF level was associated with MDD. Plasma GDNF level was measured in 23 healthy control subjects and 23 MDD patients before and after 6 weeks of treatment. Plasma GDNF level in MDD patients at baseline did not differ from that in healthy controls. Plasma GDNF in MDD patients did not differ significantly from baseline to the end of treatment. GDNF level was significantly lower in recurrent-episode MDD patients than in first-episode patients before and after treatment. Our findings revealed significantly lower plasma GDNF level in recurrent-episode MDD patients, although plasma GDNF levels in MDD patients and healthy controls did not differ significantly. The discrepancy between our study and previous studies might arise from differences in the recurrence of depression or the ages of the MDD patients.

  2. Hydrogen Fuel Cell Performance as Telecommunications Backup Power in the United States

    Energy Technology Data Exchange (ETDEWEB)

    Kurtz, Jennifer [National Renewable Energy Lab. (NREL), Golden, CO (United States); Saur, Genevieve [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sprik, Sam [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-03-01

    Working in collaboration with the U.S. Department of Energy (DOE) and industry project partners, the National Renewable Energy Laboratory (NREL) acts as the central data repository for the data collected from real-world operation of fuel cell backup power systems. With American Recovery and Reinvestment Act of 2009 (ARRA) co-funding awarded through DOE's Fuel Cell Technologies Office, more than 1,300 fuel cell units were deployed over a three-plus-year period in stationary, material handling equipment, auxiliary power, and backup power applications. This surpassed a Fuel Cell Technologies Office ARRA objective to spur commercialization of an early market technology by installing 1,000 fuel cell units across several different applications, including backup power. By December 2013, 852 backup power units out of 1,330 fuel cell units deployed were providing backup service, mainly for telecommunications towers. For 136 of the fuel cell backup units, project participants provided detailed operational data to the National Fuel Cell Technology Evaluation Center for analysis by NREL's technology validation team. NREL analyzed operational data collected from these government co-funded demonstration projects to characterize key fuel cell backup power performance metrics, including reliability and operation trends, and to highlight the business case for using fuel cells in these early market applications. NREL's analyses include these critical metrics, along with deployment, U.S. grid outage statistics, and infrastructure operation.

  3. The effect of material properties on the performance of a new geometry PEM fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Khazaee, Iman [Islamic Azad University, Department of Mechanical Engineering, Torbat-e-jam Branch, Torbat-e-jam (Iran, Islamic Republic of); Ghazikhani, Mohsen [Ferdowsi University of Mashhad, Department of Mechanical Engineering, Faculty of Engineering, Mashhad (Iran, Islamic Republic of)

    2012-05-15

    In this paper a computational dynamics model for duct-shaped geometry proton exchange membrane (PEM) fuel cell was used to investigate the effect of changing gas diffusion layer and membrane properties on the performances, current density and gas concentration. The proposed model is a full cell model, which includes all the parts of the PEM fuel cell, flow channels, gas diffusion electrodes, catalyst layers and the membrane. Coupled transport and electrochemical kinetics equations are solved in a single domain; therefore no interfacial boundary condition is required at the internal boundaries between cell components. This computational fluid dynamics code is used as the direct problem solver, which is used to simulate the 2-dimensional mass, momentum and species transport phenomena as well as the electron- and proton-transfer process taking place in a PEMFC that cannot be investigated experimentally. The results show that by increasing the thickness and decreasing the porosity of GDL the performance of the cell enhances that it is different with planner PEM fuel cell. Also the results show that by increasing the thermal conductivity of the GDL and membrane, the overall cell performance increases. (orig.)

  4. Introducing catalyst in alkaline membrane for improved performance direct borohydride fuel cells

    Science.gov (United States)

    Qin, Haiying; Lin, Longxia; Chu, Wen; Jiang, Wei; He, Yan; Shi, Qiao; Deng, Yonghong; Ji, Zhenguo; Liu, Jiabin; Tao, Shanwen

    2018-01-01

    A catalytic material is introduced into the polymer matrix to prepare a novel polymeric alkaline electrolyte membrane (AEM) which simultaneously increases ionic conductivity, reduces the fuel cross-over. In this work, the hydroxide anion exchange membrane is mainly composed of poly(vinylalcohol) and alkaline exchange resin. CoCl2 is added into the poly(vinylalcohol) and alkaline exchange resin gel before casting the membrane to introduce catalytic materials. CoCl2 is converted into CoOOH after the reaction with KOH solution. The crystallinity of the polymer matrix decreases and the ionic conductivity of the composite membrane is notably improved by the introduction of Co-species. A direct borohydride fuel cell using the composite membrane exhibits an open circuit voltage of 1.11 V at 30 °C, which is notably higher than that of cells using other AEMs. The cell using the composite membrane achieves a maximum power density of 283 mW cm-2 at 60 °C while the cell using the membrane without Co-species only reaches 117 mW cm-2 at the same conditions. The outstanding performance of the cell using the composite membrane benefits from impregnation of the catalytic Co-species in the membrane, which not only increases the ionic conductivity but also reduces electrode polarization thus improves the fuel cell performance. This work provides a new approach to develop high-performance fuel cells through adding catalysts in the electrolyte membrane.

  5. Experimental study of commercial size proton exchange membrane fuel cell performance

    International Nuclear Information System (INIS)

    Yan, Wei-Mon; Wang, Xiao-Dong; Lee, Duu-Jong; Zhang, Xin-Xin; Guo, Yi-Fan; Su, Ay

    2011-01-01

    Commercial sized (16 x 16 cm 2 active surface area) proton exchange membrane (PEM) fuel cells with serpentine flow chambers are fabricated. The GORE-TEX (registered) PRIMEA 5621 was used with a 35-μm-thick PEM with an anode catalyst layer with 0.45 mg cm -2 Pt and cathode catalyst layer with 0.6 mg cm -2 Pt and Ru or GORE-TEX (registered) PRIMEA 57 was used with an 18-μm-thick PEM with an anode catalyst layer at 0.2 mg cm -2 Pt and cathode catalyst layer at 0.4 mg cm -2 of Pt and Ru. At the specified cell and humidification temperatures, the thin PRIMEA 57 membrane yields better cell performance than the thick PRIMEA 5621 membrane, since hydration of the former is more easily maintained with the limited amount of produced water. Sufficient humidification at both the cathode and anode sides is essential to achieve high cell performance with a thick membrane, like the PRIMEA 5621. The optimal cell temperature to produce the best cell performance with PRIMEA 5621 is close to the humidification temperature. For PRIMEA 57, however, optimal cell temperature exceeds the humidification temperature.

  6. Performance effects of coal-derived contaminants on the carbonate fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Pigeaud, A. [Energy Research Corp., Danbury, CT (United States); Wilemski, G. [Physical Sciences, Inc., Andover, MA (United States)

    1993-05-01

    Coal-derived contaminant studies have been pursued at ERC since the early 1980`s when the pace of carbonate fuel cell development began to markedly increase. Initial work was concerned with performance effects on laboratory and bench-scale carbonate fuel cells primarily due to sulfur compounds. Results have now also been obtained with respect to nine additional coal-gas contaminants, including volatile trace metal species. Thermochemical calculations, out-of-cell experiments, and cell performance as well as endurance testshave recently been conducted which have involved the following species: NH{sub 3}, H{sub 2}S [COS], HCl, AsH{sub 3}[As{sub 2}(v)], Zn(v), Pb(v), Cd(v), H{sub 2} Se, Hg(v), Sn(v). Employing thermochemically calculated results, thermogravimetric (TGA) and pre-, and post-test analytical data as well as fuel cell performance observations, it has been shown that there are four main mechanisms of contaminant interaction with the carbonate fuel cell. These have been formulated into performance models for six significant contaminant species, thus providing long-term endurance estimations.

  7. Performance effects of coal-derived contaminants on the carbonate fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Pigeaud, A. (Energy Research Corp., Danbury, CT (United States)); Wilemski, G. (Physical Sciences, Inc., Andover, MA (United States))

    1993-01-01

    Coal-derived contaminant studies have been pursued at ERC since the early 1980's when the pace of carbonate fuel cell development began to markedly increase. Initial work was concerned with performance effects on laboratory and bench-scale carbonate fuel cells primarily due to sulfur compounds. Results have now also been obtained with respect to nine additional coal-gas contaminants, including volatile trace metal species. Thermochemical calculations, out-of-cell experiments, and cell performance as well as endurance testshave recently been conducted which have involved the following species: NH[sub 3], H[sub 2]S [COS], HCl, AsH[sub 3][As[sub 2](v)], Zn(v), Pb(v), Cd(v), H[sub 2] Se, Hg(v), Sn(v). Employing thermochemically calculated results, thermogravimetric (TGA) and pre-, and post-test analytical data as well as fuel cell performance observations, it has been shown that there are four main mechanisms of contaminant interaction with the carbonate fuel cell. These have been formulated into performance models for six significant contaminant species, thus providing long-term endurance estimations.

  8. Understanding InP Nanowire Array Solar Cell Performance by N