AGR-1 Data Qualification Report

International Nuclear Information System (INIS)

Abbott, Michael

2010-01-01

Projects for the very high temperature reactor (VHTR) Technology Development Office (TDO) program provide data in support of Nuclear Regulatory Commission licensing of the VHTR. Fuel and materials to be used in the reactor are tested and characterized to quantify performance in high temperature and high fluence environments. The VHTR program has established the NGNP Data Management and Analysis System (NDMAS) to ensure that VHTR data are (1) qualified for use, (2) stored in a readily accessible electronic form, and (3) analyzed to extract useful results. This document focuses on the first NDMAS objective. It describes the data streams associated with the first Advanced Gas Reactor experiment (AGR-1), the processing of these data within NDMAS, and reports the qualification status of the data. Data qualification activities within NDMAS for specific types of data are determined by the data qualification category assigned by the data generator. They include: (1) capture testing, to confirm that the data stored within NDMAS are identical to the raw data supplied, (2) accuracy testing, to confirm that the data are an accurate representation of the system or object being measured, and (3) documentation that the data were collected under an NQA-1 or equivalent quality assurance program. The NDMAS database processing and qualification status of the following five data streams is reported in this document: (1) Fuel fabrication data. All data have been processed into the NDMAS database and qualified (1,819 records). (2) Fuel irradiation data. Data from all 13 AGR-1 reactor cycles have been processed into the NDMAS database and tested. Of these, 85% have been qualified and 15% have failed NDMAS accuracy testing. (3) FPMS data. Reprocessed (January 2010) data from all 13 AGR-1 reactor cycles have been processed into the database and capture tested. Final qualification of these data will be recorded after QA approval of an Engineering Calculations and Analysis Report currently

Reinforced Carbon Carbon (RCC) oxidation resistant material samples - Baseline coated, and baseline coated with tetraethyl orthosilicate (TEOS) impregnation

Science.gov (United States)

Gantz, E. E.

1977-01-01

Reinforced carbon-carbon material specimens were machined from 19 and 33 ply flat panels which were fabricated and processed in accordance with the specifications and procedures accepted for the fabrication and processing of the leading edge structural subsystem (LESS) elements for the space shuttle orbiter. The specimens were then baseline coated and tetraethyl orthosilicate impregnated, as applicable, in accordance with the procedures and requirements of the appropriate LESS production specifications. Three heater bars were ATJ graphite silicon carbide coated with the Vought 'pack cementation' coating process, and three were stackpole grade 2020 graphite silicon carbide coated with the chemical vapor deposition process utilized by Vought in coating the LESS shell development program entry heater elements. Nondestructive test results are reported.

AGR-2 irradiation test final as-run report, Rev. 1

International Nuclear Information System (INIS)

2014-01-01

test contained six independently controlled and monitored capsules. Each U.S. capsule contained 12 compacts of either UCO or UO 2 AGR coated fuel. No fuel particles failed during the AGR-2 irradiation. Final burnup values on a per compact basis ranged from 7.26 to 13.15% FIMA (fissions per initial heavy-metal atom) for UCO fuel, and 9.01 to 10.69% FIMA for UO 2 fuel, while fast fluence values ranged from 1.94 to 3.47x10 25 n/m 2 (E >0.18 MeV) for UCO fuel, and from 3.05 to 3.53x10 25 n/m 2 (E >0.18 MeV) for UO 2 fuel. Time-average volume-average (TAVA) temperatures on a capsule basis at the end of irradiation ranged from 987°C in Capsule 6 to 1296°C in Capsule 2 for UCO, and from 996 to 1062°C in UO 2 -fueled Capsule 3. By the end of the irradiation, all of the installed thermocouples (TCs) had failed. Fission product release-to-birth (R/B) ratios were quite low. In the UCO capsules, R/B values during the first three cycles were below 10 -6 with the exception of the hotter Capsule 2, in which the R/Bs reached 2x10 -6 . In the UO 2 capsule (Capsule 3), the R/B values during the first three cycles were below 10 -7 . R/B values for all following cycles are not reliable due to gas flow and cross talk issues.

Advanced electron microscopic techniques applied to the characterization of irradiation effects and fission product identification of irradiated TRISO coated particles from the AGR-1 experiment

International Nuclear Information System (INIS)

Rooyen, I.J. van; Lillo, T.M.; Trowbridge, T.L.; Madden, J.M.; Wu, Y.Q.; Goran, D.

2013-01-01

Preliminary electron microscopy of coated fuel particles from the AGR-1 experiment was conducted using characterization techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), and wavelength dispersive spectroscopy (WDS). Microscopic quantification of fission-product precipitates was performed. Although numerous micro- and nano-sized precipitates observed in the coating layers during initial SEM characterization of the cross-sections, and in subsequent TEM diffraction patterns, were indexed as UPd 2 Si 2 , no Ag was conclusively found. Additionally, characterization of these precipitates highlighted the difficulty of measuring low concentrations of Ag in precipitates in the presence of significantly higher concentrations of Pd and U. The electron microscopy team followed a multi-directional and phased approach in the identification of fission products in irradiated TRISO fuel. The advanced electron microscopy techniques discussed in this paper, not only demonstrate the usefulness of the equipment (methods) as relevant research tools, but also provide relevant scientific results which increase the knowledge about TRISO fuel particles microstructure and fission products transport

AGR-1 Data Qualification Interim Report

International Nuclear Information System (INIS)

Abbott, Machael

2009-01-01

Projects for the very-high-temperature reactor (VHTR) program provide data in support of Nuclear Regulatory Commission licensing of the VHTR. Fuel and materials to be used in the reactor are tested and characterized to quantify performance in high temperature and high fluence environments. The VHTR Program has established the NGNP Data Management and Analysis System (NDMAS) to ensure that VHTR data are (1) qualified for use, (2) stored in a readily accessible electronic form, and (3) analyzed to extract useful results. This document focuses on the first NDMAS objective. It describes the data streams associated with the first Advanced Gas Reactor (AGR-1) experiment, the processing of these data within NDMAS, and reports the interim FY09 qualification status of the AGR-1 data to date. Data qualification activities within NDMAS for specific types of data are determined by the data qualification category, which is assigned by the data generator, and include: (1) capture testing, to confirm that the data stored within NDMAS are identical to the raw data supplied, (2) accuracy testing, to confirm that the data are an accurate representation of the system or object being measured, and (3) documentation that the data were collected under an NQA-1 or equivalent QA program. The interim qualification status of the following four data streams is reported in this document: (1) fuel fabrication data, (2) fuel irradiation data, (3) fission product monitoring system (FPMS) data, and (4) Advanced Test Reactor (ATR) operating conditions data. A final report giving the NDMAS qualification status of all AGR-1 data (including cycle 145A) is planned for February 2010

Irradiation performance of AGR-1 high temperature reactor fuel

Energy Technology Data Exchange (ETDEWEB)

Paul A. Demkowicz; John D. Hunn; Robert N. Morris; Charles A. Baldwin; Philip L. Winston; Jason M. Harp; Scott A. Ploger; Tyler Gerczak; Isabella J. van Rooyen; Fred C. Montgomery; Chinthaka M. Silva

2014-10-01

The AGR-1 experiment contained 72 low-enriched uranium oxide/uranium carbide TRISO-coated particle fuel compacts in six capsules irradiated to burnups of 11.2 to 19.5% FIMA, with zero TRISO coating failures detected during the irradiation. The irradiation performance of the fuel–including the extent of fission product release and the evolution of kernel and coating microstructures–was evaluated based on detailed examination of the irradiation capsules, the fuel compacts, and individual particles. Fractional release of 110mAg from the fuel compacts was often significant, with capsule-average values ranging from 0.01 to 0.38. Analysis of silver release from individual compacts indicated that it was primarily dependent on fuel temperature history. Europium and strontium were released in small amounts through intact coatings, but were found to be significantly retained in the outer pyrocrabon and compact matrix. The capsule-average fractional release from the compacts was 1×10 4 to 5×10 4 for 154Eu and 8×10 7 to 3×10 5 for 90Sr. The average 134Cs release from compacts was <3×10 6 when all particles maintained intact SiC. An estimated four particles out of 2.98×105 experienced partial cesium release due to SiC failure during the irradiation, driving 134Cs release in two capsules to approximately 10 5. Identification and characterization of these particles has provided unprecedented insight into the nature and causes of SiC coating failure in high-quality TRISO fuel. In general, changes in coating morphology were found to be dominated by the behavior of the buffer and inner pyrolytic carbon (IPyC), and infrequently observed SiC layer damage was usually related to cracks in the IPyC. Palladium attack of the SiC layer was relatively minor, except for the particles that released cesium during irradiation, where SiC corrosion was found adjacent to IPyC cracks. Palladium, silver, and uranium were found in the SiC layer of irradiated particles, and characterization

AGR 3/4 Irradiation Test Final As Run Report

Energy Technology Data Exchange (ETDEWEB)

Collin, Blaise P. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2015-06-01

Several fuel and material irradiation experiments have been planned for the Idaho National Laboratory Advanced Reactor Technologies Technology Development Office Advanced Gas Reactor Fuel Development and Qualification Program (referred to as the INL ART TDO/AGR fuel program hereafter), which supports the development and qualification of tristructural-isotropic (TRISO) coated particle fuel for use in HTGRs. The goals of these experiments are to provide irradiation performance data to support fuel process development, qualify fuel for normal operating conditions, support development and validation of fuel performance and fission product transport models and codes, and provide irradiated fuel and materials for post irradiation examination and safety testing (INL 05/2015). AGR-3/4 combined the third and fourth in this series of planned experiments to test TRISO coated low enriched uranium (LEU) oxycarbide fuel. This combined experiment was intended to support the refinement of fission product transport models and to assess the effects of sweep gas impurities on fuel performance and fission product transport by irradiating designed-to-fail fuel particles and by measuring subsequent fission metal transport in fuel-compact matrix material and fuel-element graphite. The AGR 3/4 fuel test was successful in irradiating the fuel compacts to the burnup and fast fluence target ranges, considering the experiment was terminated short of its initial 400 EFPD target (Collin 2015). Out of the 48 AGR-3/4 compacts, 42 achieved the specified burnup of at least 6% fissions per initial heavy-metal atom (FIMA). Three capsules had a maximum fuel compact average burnup < 10% FIMA, one more than originally specified, and the maximum fuel compact average burnup was <19% FIMA for the remaining capsules, as specified. Fast neutron fluence fell in the expected range of 1.0 to 5.5×1025 n/m2 (E >0.18 MeV) for all compacts. In addition, the AGR-3/4 experiment was globally successful in keeping the

Fission product monitoring of TRISO coated fuel for the advanced gas reactor-1 experiment

International Nuclear Information System (INIS)

Scates, Dawn M.; Hartwell, John K.; Walter, John B.; Drigert, Mark W.; Harp, Jason M.

2010-01-01

The US Department of Energy has embarked on a series of tests of TRISO coated particle reactor fuel intended for use in the Very High Temperature Reactor (VHTR) as part of the Advanced Gas Reactor (AGR) program. The AGR-1 TRISO fuel experiment, currently underway, is the first in a series of eight fuel tests planned for irradiation in the Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL). The AGR-1 experiment reached a peak compact averaged burnup of 9% FIMA with no known TRISO fuel particle failures in March 2008. The burnup goal for the majority of the fuel compacts is to have a compact averaged burnup greater than 18% FIMA and a minimum compact averaged burnup of 14% FIMA. At the INL the TRISO fuel in the AGR-1 experiment is closely monitored while it is being irradiated in the ATR. The effluent monitoring system used for the AGR-1 fuel is the Fission Product Monitoring System (FPMS). The FPMS is a valuable tool that provides near real-time data indicative of the AGR-1 test fuel performance and incorporates both high-purity germanium (HPGe) gamma-ray spectrometers and sodium iodide [NaI(Tl)] scintillation detector-based gross radiation monitors. To quantify the fuel performance, release-to-birth ratios (R/B's) of radioactive fission gases are computed. The gamma-ray spectra acquired by the AGR-1 FPMS are analyzed and used to determine the released activities of specific fission gases, while a dedicated detector provides near-real time count rate information. Isotopic build up and depletion calculations provide the associated isotopic birth rates. This paper highlights the features of the FPMS, encompassing the equipment, methods and measures that enable the calculation of the release-to-birth ratios. Some preliminary results from the AGR-1 experiment are also presented.

HIGH-TEMPERATURE SAFETY TESTING OF IRRADIATED AGR-1 TRISO FUEL

Energy Technology Data Exchange (ETDEWEB)

Stempien, John D.; Demkowicz, Paul A.; Reber, Edward L.; Chrisensen, Cad L.

2016-11-01

High-Temperature Safety Testing of Irradiated AGR-1 TRISO Fuel John D. Stempien, Paul A. Demkowicz, Edward L. Reber, and Cad L. Christensen Idaho National Laboratory, P.O. Box 1625 Idaho Falls, ID 83415, USA Corresponding Author: john.stempien@inl.gov, +1-208-526-8410 Two new safety tests of irradiated tristructural isotropic (TRISO) coated particle fuel have been completed in the Fuel Accident Condition Simulator (FACS) furnace at the Idaho National Laboratory (INL). In the first test, three fuel compacts from the first Advanced Gas Reactor irradiation experiment (AGR-1) were simultaneously heated in the FACS furnace. Prior to safety testing, each compact was irradiated in the Advanced Test Reactor to a burnup of approximately 15 % fissions per initial metal atom (FIMA), a fast fluence of 3×1025 n/m2 (E > 0.18 MeV), and a time-average volume-average (TAVA) irradiation temperature of about 1020 °C. In order to simulate a core-conduction cool-down event, a temperature-versus-time profile having a peak temperature of 1700 °C was programmed into the FACS furnace controllers. Gaseous fission products (i.e., Kr-85) were carried to the Fission Gas Monitoring System (FGMS) by a helium sweep gas and captured in cold traps featuring online gamma counting. By the end of the test, a total of 3.9% of an average particle’s inventory of Kr-85 was detected in the FGMS traps. Such a low Kr-85 activity indicates that no TRISO failures (failure of all three TRISO layers) occurred during the test. If released from the compacts, condensable fission products (e.g., Ag-110m, Cs-134, Cs-137, Eu-154, Eu-155, and Sr-90) were collected on condensation plates fitted to the end of the cold finger in the FACS furnace. These condensation plates were then analyzed for fission products. In the second test, five loose UCO fuel kernels, obtained from deconsolidated particles from an irradiated AGR-1 compact, were heated in the FACS furnace to a peak temperature of 1600 °C. This test had two

Impact on burnup performance of coated particle fuel design in pebble bed reactor with ROX fuel

International Nuclear Information System (INIS)

Ho, Hai Quan; Obara, Toru

2015-01-01

The pebble bed reactor (PBR), a kind of high-temperature gas-cooled reactor (HTGR), is expected to be among the next generation of nuclear reactors as it has excellent passive safety features, as well as online refueling and high thermal efficiency. Rock-like oxide (ROX) fuel has been studied at the Japan Atomic Energy Agency (JAEA) as a new once-through type fuel concept. Rock-like oxide used as fuel in a PBR can be expected to achieve high burnup and improve chemical stabilities. In the once-through fuel concept, the main challenge is to achieve as high a burnup as possible without failure of the spent fuel. The purpose of this study was to investigate the impact on burnup performance of different coated fuel particle (CFP) designs in a PBR with ROX fuel. In the study, the AGR-1 Coated Particle design and Deep-Burn Coated Particle design were used to make the burnup performance comparison. Criticality and core burnup calculations were performed by MCPBR code using the JENDL-4.0 library. Results at equilibrium showed that the two reactors utilizing AGR-1 Coated Particle and Deep-Burn Coated Particle designs could be critical with almost the same multiplication factor k eff . However, the power peaking factor and maximum power per fuel ball in the AGR-1 coated particle design was lower than that of Deep-Burn coated particle design. The AGR-1 design also showed an advantage in fissions per initial fissile atoms (FIFA); the AGR-1 coated particle design produced a higher FIFA than the Deep-Burn coated particle design. These results suggest that the difference in coated particle fuel design can have an effect on the burnup performance in ROX fuel. (author)

X-ray Analysis of Defects and Anomalies in AGR-5/6/7 TRISO Particles

Energy Technology Data Exchange (ETDEWEB)

Helmreich, Grant W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hunn, John D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Skitt, Darren J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dyer, John A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Schumacher, Austin T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-06-01

Coated particle fuel batches J52O-16-93164, 93165, 93166, 93168, 93169, 93170, and 93172 were produced by Babcock and Wilcox Technologies (BWXT) for possible selection as fuel for the Advanced Gas Reactor Fuel Development and Qualification (AGR) Program’s AGR-5/6/7 irradiation test in the Idaho National Laboratory (INL) Advanced Test Reactor (ATR), or may be used for other tests. Each batch was coated in a 150-mm-diameter production-scale fluidized-bed chemical vapor deposition (CVD) furnace. Tristructural isotropic (TRISO) coatings were deposited on 425-μm-nominal-diameter spherical kernels from BWXT lot J52R-16-69317 containing a mixture of 15.4%-enriched uranium carbide and uranium oxide (UCO), with the exception of Batch 93164, which used similar kernels from BWXT lot J52L-16-69316. The TRISO-coatings consisted of a ~50% dense carbon buffer layer with 100-μmnominal thickness, a dense inner pyrolytic carbon (IPyC) layer with 40-μm-nominal thickness, a silicon carbide (SiC) layer with 35-μm-nominal thickness, and a dense outer pyrolytic carbon (OPyC) layer with 40-μm-nominal thickness. Each coated particle batch was sieved to upgrade the particles by removing over-sized and under-sized material, and the upgraded batch was designated by appending the letter A to the end of the batch number (e.g., 93164A). Secondary upgrading by sieving was performed on the upgraded batches to remove specific anomalies identified during analysis for Defective IPyC, and the upgraded batches were designated by appending the letter B to the end of the batch number (e.g., 93165B). Following this secondary upgrading, coated particle composite J52R-16-98005 was produced by BWXT as fuel for the AGR Program’s AGR-5/6/7 irradiation test in the INL ATR. This composite was comprised of coated particle fuel batches J52O-16-93165B, 93168B, 93169B, and 93170B.

AGR-1 Fuel Compact 6-3-2 Post-Irradiation Examination Results

Energy Technology Data Exchange (ETDEWEB)

Paul demkowicz; jason Harp; Scott Ploger

2012-12-01

Destructive post-irradiation examination was performed on fuel Compact 6-3-2, which was irradiated in the AGR-1 experiment to a final compact average burnup of 11.3% FIMA and a time-average, volume-average temperature of 1070°C. The analysis of this compact was focused on characterizing the extent of fission product release from the particles and examining particles to determine the condition of the kernels and coating layers. The work included deconsolidation of the compact and leach-burn-leach analysis, visual inspection and gamma counting of individual particles, measurement of fuel burnup by several methods, metallurgical preparation of selected particles, and examination of particle cross-sections with optical microscopy. A single particle with a defective SiC layer was identified during deconsolidation-leach-burn-leach analysis, which is in agreement with previous measurements showing elevated cesium in the Capsule 6 graphite fuel holder associated with this fuel compact. The fraction of the compact europium inventory released from the particles and retained in the matrix was relatively high (approximately 6E-3), indicating release from intact particle coatings. The Ag-110m inventory in individual particles exhibited a very broad distribution, with some particles retaining =80% of the predicted inventory and others retaining less than 25%. The average degree of Ag-110m retention in 60 gamma counted particles was approximately 50%. This elevated silver release is in agreement with analysis of silver on the Capsule 6 components, which indicated an average release of 38% of the Capsule 6 inventory from the fuel compacts. In spite of the relatively high degree of silver release from the particles, virtually none of the Ag-110m released was found in the compact matrix, and presumably migrated out of the compact and was deposited on the irradiation capsule components. Release of all other fission products from the particles appears to be less than a single

Pentek metal coating removal system: Baseline report

International Nuclear Information System (INIS)

1997-01-01

The Pentek coating removal technology was tested and is being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU's evaluation of efficiency and cost, this report covers evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The Pentek coating removal system consisted of the ROTO-PEEN Scaler, CORNER-CUTTER reg-sign, and VAC-PAC reg-sign. They are designed to remove coatings from steel, concrete, brick, and wood. The Scaler uses 3M Roto Peen tungsten carbide cutters while the CORNER-CUTTER reg-sign uses solid needles for descaling activities. These hand tools are used with the VAC-PAC reg-sign vacuum system to capture dust and debris as removal of the coating takes place. The safety and health evaluation during the testing demonstration focused on two main areas of exposure: dust and noise. Dust exposure minimal, but noise exposure was significant. Further testing for each exposure is recommended because of the environment where the testing demonstration took place. It is feasible that the dust and noise levels will be higher in an enclosed operating environment of different construction. In addition, other areas of concern found were arm-hand vibration, whole-body, ergonomics, heat stress, tripping hazards, electrical hazards, machine guarding, and lockout/tagout

AGR-5/6/7 Irradiation Test Predictions using PARFUME

Energy Technology Data Exchange (ETDEWEB)

Skerjanc, William F. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2017-09-14

PARFUME, (PARticle FUel ModEl) a fuel performance modeling code used for high temperature gas-cooled reactors (HTGRs), was used to model the Advanced Gas Reactor (AGR)-5/6/7 irradiation test using predicted physics and thermal hydraulics data. The AGR-5/6/7 test consists of the combined fifth, sixth, and seventh planned irradiations of the AGR Fuel Development and Qualification Program. The AGR-5/6/7 test train is a multi-capsule, instrumented experiment that is designed for irradiation in the 133.4-mm diameter north east flux trap (NEFT) position of Advanced Test Reactor (ATR). Each capsule contains compacts filled with uranium oxycarbide (UCO) unaltered fuel particles. This report documents the calculations performed to predict the failure probability of tristructural isotropic (TRISO)-coated fuel particles during the AGR-5/6/7 experiment. In addition, this report documents the calculated source term from the driver fuel. The calculations include modeling of the AGR-5/6/7 irradiation that is scheduled to occur from October 2017 to April 2021 over a total of 13 ATR cycles, including nine normal cycles and four Power Axial Locator Mechanism (PALM) cycle for a total between 500 – 550 effective full power days (EFPD). The irradiation conditions and material properties of the AGR-5/6/7 test predicted zero fuel particle failures in Capsules 1, 2, and 4. Fuel particle failures were predicted in Capsule 3 due to internal particle pressure. These failures were predicted in the highest temperature compacts. Capsule 5 fuel particle failures were due to inner pyrolytic carbon (IPyC) cracking causing localized stresses concentrations in the SiC layer. This capsule predicted the highest particle failures due to the lower irradiation temperature. In addition, shrinkage of the buffer and IPyC layer during irradiation resulted in formation of a buffer-IPyC gap. The two capsules at the two ends of the test train, Capsules 1 and 5 experienced the smallest buffer-IPyC gap

Analysis of fission gas release-to-birth ratio data from the AGR irradiations

International Nuclear Information System (INIS)

Einerson, Jeffrey J.; Pham, Binh T.; Scates, Dawn M.; Maki, John T.; Petti, David A.

2016-01-01

A series of advanced gas reactor (AGR) irradiation tests is being conducted in the advanced test reactor (ATR) at Idaho National Laboratory (INL) in support of development and qualification of tristructural isotropic (TRISO) fuel used in the High temperature gas-cooled reactor (HTGR). Each AGR test consists of multiple independent capsules containing fuel compacts placed in a graphite cylinder shrouded by a steel shell. These capsules are instrumented with thermocouples (TC) embedded in the graphite enabling temperature control. For AGR-1, the first US irradiation of modern TRISO fuel completed in 2009, there were no particle failures detected. For AGR-2, a few exposed kernels existed in the fuel compacts based upon quality control data. For the AGR-3/4 experiment, particle failures in all capsules were expected because of the use of designed-to-fail (DTF) fuel particles whose kernels are identical to the driver fuel kernels and whose coatings are designed to fail under irradiation. The release-rate-to-birth-rate ratio (R/B) for each of krypton and xenon isotopes is calculated from release rates measured by the germanium detectors used in the AGR fission product monitoring (FPM) system installed downstream from each irradiated capsule. Birth rates are calculated based on the fission power in the experiment and fission product generation models. Thus, this R/B is a measure of the ability of fuel particle coating layers and compact matrix to retain fission gas atoms preventing their release into the sweep gas flow. The major factors that govern gaseous diffusion and release processes are found to be fuel material diffusion coefficient, temperature, and isotopic decay constant. To compare the release behavior among the AGR capsules and historic experiments, the R/B per failed particle is used. HTGR designers use this parameter in their fission product behavior models. For the U.S. TRISO fuel, a regression analysis is performed to establish functional relationships

Analysis of Fission Gas Release-to-Birth Ratio Data from the AGR Irradiations

International Nuclear Information System (INIS)

Einerson, Jeffrey J.; Pham, Binh T.; Scates, Dawn M.; Maki, John T.; Petti, David A.

2014-01-01

A series of Advanced Gas Reactor (AGR) irradiation tests is being conducted in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) in support of development and qualification of tristructural isotropic (TRISO) fuel used in the High Temperature Gas-cooled Reactor (HTGR). Each AGR test consists of multiple independent capsules containing fuel compacts placed in a graphite cylinder shrouded by a steel shell. These capsules are instrumented with thermocouples (TC) embedded in the graphite enabling temperature control. For AGR-1, the first US irradiation of modern TRISO fuel completed in 2009, there were no particle failures detected. For AGR-2, a few exposed kernels existed in the fuel compacts based upon quality control data. For the AGR-3/4 experiment, particle failures in all capsules were expected because of the use of designed-to-fail (DTF) fuel particles whose kernels are identical to the driver fuel kernels and whose coatings are designed to fail under irradiation. The release-rate-to-birth-rate ratio (R/B) for each of krypton and xenon isotopes is calculated from release rates measured by the germanium detectors used in the AGR Fission Product Monitoring (FPM) System installed downstream from each irradiated capsule. Birth rates are calculated based on the fission power in the experiment and fission product generation models. Thus, this R/B is a measure of the ability of fuel particle coating layers and compact matrix to retain fission gas atoms preventing their release into the sweep gas flow. The major factors that govern gaseous diffusion and release processes are found to be fuel material diffusion coefficient, temperature, and isotopic decay constant. To compare the release behavior among the AGR capsules and historic experiments, the R/B per failed particle is used. HTGR designers use this parameter in their fission product behavior models. For the U.S. TRISO fuel, a regression analysis is performed to establish functional relationships

Analysis of fission gas release-to-birth ratio data from the AGR irradiations

Energy Technology Data Exchange (ETDEWEB)

Einerson, Jeffrey J., E-mail: jeffrey.einerson@inl.gov; Pham, Binh T.; Scates, Dawn M.; Maki, John T.; Petti, David A.

2016-09-15

A series of advanced gas reactor (AGR) irradiation tests is being conducted in the advanced test reactor (ATR) at Idaho National Laboratory (INL) in support of development and qualification of tristructural isotropic (TRISO) fuel used in the High temperature gas-cooled reactor (HTGR). Each AGR test consists of multiple independent capsules containing fuel compacts placed in a graphite cylinder shrouded by a steel shell. These capsules are instrumented with thermocouples (TC) embedded in the graphite enabling temperature control. For AGR-1, the first US irradiation of modern TRISO fuel completed in 2009, there were no particle failures detected. For AGR-2, a few exposed kernels existed in the fuel compacts based upon quality control data. For the AGR-3/4 experiment, particle failures in all capsules were expected because of the use of designed-to-fail (DTF) fuel particles whose kernels are identical to the driver fuel kernels and whose coatings are designed to fail under irradiation. The release-rate-to-birth-rate ratio (R/B) for each of krypton and xenon isotopes is calculated from release rates measured by the germanium detectors used in the AGR fission product monitoring (FPM) system installed downstream from each irradiated capsule. Birth rates are calculated based on the fission power in the experiment and fission product generation models. Thus, this R/B is a measure of the ability of fuel particle coating layers and compact matrix to retain fission gas atoms preventing their release into the sweep gas flow. The major factors that govern gaseous diffusion and release processes are found to be fuel material diffusion coefficient, temperature, and isotopic decay constant. To compare the release behavior among the AGR capsules and historic experiments, the R/B per failed particle is used. HTGR designers use this parameter in their fission product behavior models. For the U.S. TRISO fuel, a regression analysis is performed to establish functional relationships

Detection and Analysis of Particles with Failed SiC in AGR-1 Fuel Compacts

International Nuclear Information System (INIS)

Hunn, John D.; Baldwin, Charles A.; Gerczak, Tyler J.; Montgomery, Fred C.; Morris, Robert N.; Silva, Chinthaka M.; Demkowicz, Paul A.; Harp, Jason M.; Ploger, Scott A.

2014-01-01

As the primary barrier to release of radioactive isotopes emitted from the fuel kernel, retention performance of the SiC layer in tristructural isotropic (TRISO) coated particles is critical to the overall safety of reactors that utilize this fuel design. Most isotopes are well-retained by intact SiC coatings, so pathways through this layer due to cracking, structural defects, or chemical attack can significantly contribute to radioisotope release. In the US TRISO fuel development effort, release of "1"3"4Cs and "1"3"7Cs are used to detect SiC failure during fuel compact irradiation and safety testing because the amount of cesium released by a compact containing one particle with failed SiC is typically ten or more times higher than that released by compacts without failed SiC. Compacts with particles that released cesium during the AGR-1 irradiation test or post-irradiation safety testing at 1600– 1800°C were identified, and individual particles with abnormally low cesium retention were sorted out with the ORNL Irradiated Microsphere Gamma Analyzer (IMGA). X-ray tomography was used for three-dimensional imaging of the internal coating structure to locate low-density pathways through the SiC layer and guide subsequent materialography by optical and scanning electron microscopy. All three cesium-releasing particles recovered from as-irradiated compacts showed a region where the inner pyrocarbon (IPyC) had cracked due to radiation-induced dimensional changes in the shrinking buffer and the exposed SiC had experienced concentrated attack by palladium; SiC failures observed in particles subjected to safety testing were related to either fabrication defects or showed extensive Pd corrosion through the SiC where it had been exposed by similar IPyC cracking. (author)

ELECTRON PROBE MICROANALYSIS OF IRRADIATED AND 1600°C SAFETY-TESTED AGR-1 TRISO FUEL PARTICLES WITH LOW AND HIGH RETAINED 110MAG

Energy Technology Data Exchange (ETDEWEB)

Wright, Karen E.; van Rooyen, Isabella J.

2016-11-01

AGR-1 fuel Compact 4-3-3 achieved 18.63% FIMA and was exposed subsequently to a safety test at 1600°C. Two particles, AGR1-433-003 and AGR1-433-007, with measured-to-calculated 110mAg inventories of <22% and 100%, respectively, were selected for comparative electron microprobe analysis to determine whether the distribution or abundance of fission products differed proximally and distally from the deformed kernel in AGR1-433-003, and how this compared to fission product distribution in AGR1-433-007. On the deformed side of AGR1-433-003, Xe, Cs, I, Eu, Sr, and Te concentrations in the kernel buffer interface near the protruded kernel were up to six times higher than on the opposite, non-deformed side. At the SiC-inner pyrolytic carbon (IPyC) interface proximal to the deformed kernel, Pd and Ag concentrations were 1.2 wt% and 0.04 wt% respectively, whereas on the SiC-IPyC interface distal from the kernel deformation those elements measured 0.4 and 0.01 wt%, respectively. Palladium and Ag concentrations at the SiC-IPyC interface of AGR1-433-007 were 2.05 and 0.05 wt.%, respectively. Rare earth element concentrations at the SiC-IPyC interface of AGR1-433-007 were a factor of ten higher than at the SiC-IPyC interfaces measured in particle AGR1-433-003. Palladium permeated the SiC layer of AGR1-433-007 and the non-deformed SiC layer of AGR1-433-003.

Acceptance Test Data for the AGR-5/6/7 Irradiation Test Fuel Composite Defective IPyC Fraction and Pyrocarbon Anisotropy

Energy Technology Data Exchange (ETDEWEB)

Helmreich, Grant W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hunn, John D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Skitt, Darren J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dyer, John A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Schumacher, Austin T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-05-01

Coated particle composite J52R-16-98005 was produced by Babcock and Wilcox Technologies (BWXT) as fuel for the Advanced Gas Reactor Fuel Development and Qualification (AGR) Program’s AGR-5/6/7 irradiation test in the Idaho National Laboratory (INL) Advanced Test Reactor (ATR). This composite was comprised of four coated particle fuel batches J52O-16-93165B (26%), 93168B (26%), 93169B (24%), and 93170B (24%), chosen based on the Quality Control (QC) data acquired for each individual candidate AGR-5/6/7 batch. Each batch was coated in a 150-mm-diameter production-scale fluidized-bed chemical vapor deposition (CVD) furnace. Tristructural isotropic (TRISO) coatings were deposited on 425-μm-nominal-diameter spherical kernels from BWXT Lot J52R-16-69317 containing a mixture of 15.5%-enriched uranium carbide and uranium oxide (UCO). The TRISO coatings consisted of four consecutive CVD layers: a ~50% dense carbon buffer layer with 100-μm-nominal thickness, a dense inner pyrolytic carbon (IPyC) layer with 40-μm-nominal thickness, a silicon carbide (SiC) layer with 35-μm-nominal thickness, and a dense outer pyrolytic carbon (OPyC) layer with 40-μm-nominal thickness. The TRISO-coated particle batches were sieved to upgrade the particles by removing over-sized and under-sized material, and the upgraded batches were designated by appending the letter A to the end of the batch number (e.g., 93165A). Secondary upgrading by sieving was performed on the A-designated batches to remove particles with missing or very-thin buffer layers that were identified during previous analysis of the individual batches for defective IPyC, as reported in the acceptance test data report for the AGR-5/6/7 production batches [Hunn et al. 2017]. The additionally-upgraded batches were designated by appending the letter B to the end of the batch number (e.g., 93165B).

Pentek metal coating removal system: Baseline report; Greenbook (chapter)

International Nuclear Information System (INIS)

1997-01-01

The Pentek coating removal technology was tested and is being evaluated at Florida International University (FIU) as a baseline technology. In conjunction with FIU's evaluation of efficiency and cost, this report covers evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The Pentek coating removal system consisted of the ROTO-PEEN Scaler, CORNER-CUTTER reg-sign, and VAC-PAC reg-sign. They are designed to remove coatings from steel, concrete, brick, and wood. The Scaler uses 3M Roto Peen tungsten carbide cutters while the CORNER-CUTTER reg-sign uses solid needles for descaling activities. These hand tools are used with the VAC-PAC reg-sign vacuum system to capture dust and debris as removal of the coating takes place. The safety and health evaluation during the testing demonstration focused on two main areas of exposure: dust and noise. Dust exposure minimal, but noise exposure was significant. Further testing for each exposure is recommended because of the environment where the testing demonstration took place. It is feasible that the dust and noise levels will be higher in an enclosed operating environment of different construction. In addition, other areas of concern found were arm-hand vibration, whole-body, ergonomics, heat stress, tripping hazards, electrical hazards, machine guarding, and lockout/tagout

Advanced fiber information systems seed coat neps baseline response from diverse mediums

Science.gov (United States)

An extensive literature search has revealed that no papers have been published regarding selectivity calculation of the AFIS seed coat neps (SCN) determination over interfering material in cotton. A prerequisite to selectivity measurements is to identify suitable fiber medium(s) that give baseline ...

Metodologías para establecer valores de referencia de metales pesados en suelos agrícolas: perspectivas para Colombia Methods for establishing baseline values for heavy metals in agricultural soils:: Prospects for Colombia

Directory of Open Access Journals (Sweden)

Germán Rueda Saa

2011-07-01

Full Text Available Los impactos ambientales de los metales pesados en los suelos están relacionados con su carácter tóxico cuando se acumulan o interactúan con algunas propiedades específicas, se movilizan a través del perfil a la cadena trófica mediante los cuerpos de agua o los cultivos y pueden llegar a afectar la salud humana. En países desarrollados el establecimiento de valores de referencia de estos metales ha permitido el mejoramiento de la planeación y la gestión ambiental del recurso suelo, y se ha convertido en un instrumento de control para las entidades ambientales que ha permitido evaluar el impacto en diferentes actividades agrícolas. En este artículo se analizan diversos conceptos relacionados con los niveles de metales pesados en suelos agrícolas y la incidencia de las características edafológicas en su concentración. Se revisan, igualmente, algunas metodologías para derivar valores de referencia específicos aplicables a suelos agrícolas colombianos, y se plantean algunas perspectivas orientadas a la protección y recuperación de suelos en el país. En Colombia en la actualidad no se cuenta con criterios y estándares de calidad para medir la contaminación por metales pesados en suelos agrícolas; por esto se hace necesario gestionar el apoyo de entidades gubernamentales con el fin de iniciar y desarrollar investigaciones en diferentes sectores agrícolas primarios, contribuyendo de esta forma a garantizar una producción más limpia y la sostenibilidad ambiental del recurso suelo.From an environmental perspective, the importance of heavy metals in soils is related to their toxicity either due to accumulation or to any interaction among them and some of their specific properties. In each case, heavy metals can move through the soil profile and transfer into the trofic chain by using through water bodies or crops affecting de human health. In developed countries, the establishment of baseline values has permitted improvements

Comparison of fission product release predictions using PARFUME with results from the AGR-1 irradiation experiment

International Nuclear Information System (INIS)

Collin, Blaise P.; Petti, David A.; Demkowicz, Paul A.; Maki, John T.

2014-01-01

The PARFUME (PARticle FUel ModEl) code was used to predict fission product release from tristructural isotropic (TRISO) coated fuel particles and compacts during the first irradiation experiment (AGR-1) of the Advanced Gas Reactor Fuel Development and Qualification program. The PARFUME model for the AGR-1 experiment used the fuel compact volume average temperature for each of the 620 days of irradiation to calculate the release of fission products silver, cesium, and strontium from a representative particle for a select number of AGR-1 compacts. Post-irradiation examination (PIE) measurements provided data on release of fission products from fuel compacts and fuel particles, and retention of fission products in the compacts outside of the silicon carbide (SiC) layer. PARFUME-predicted fractional release of these fission products was determined and compared to the PIE measurements. Results show an overall over-prediction of the fractional release of cesium by PARFUME. For particles with failed SiC layers, the over-prediction is by a factor of about two, corresponding to an over-estimation of the diffusivity in uranium oxycarbide (UCO) by a factor of about 100. For intact particles, whose release is much lower, the over-prediction is by an average of about an order of magnitude, which could additionally be attributed to an over-estimated diffusivity in SiC by about 30%. The release of strontium from intact particles is also over-estimated by PARFUME, which also points towards an over-estimated diffusivity of strontium in either SiC or UCO, or possibly both. The measured strontium fractional release from intact particles varied considerably from compact to compact, making it difficult to assess the effective over-estimation of the diffusivities. Furthermore, the release of strontium from particles with failed SiC is difficult to observe experimentally due to the release from intact particles, preventing any conclusions to be made on the accuracy or validity of the

MICRO/NANO-STRUCTURAL EXAMINATION AND FISSION PRODUCT IDENTIFICATION IN NEUTRON IRRADIATED AGR-1 TRISO FUEL

Energy Technology Data Exchange (ETDEWEB)

van Rooyen, I. J.; Lillo, T. M.; Wen, H. M.; Hill, C. M.; Holesinger, T. G.; Wu, Y. Q.; Aguiara, J. A.

2016-11-01

Advanced microscopic and microanalysis techniques were developed and applied to study irradiation effects and fission product behavior in selected low-enriched uranium oxide/uranium carbide TRISO-coated particles from fuel compacts in six capsules irradiated to burnups of 11.2 to 19.6% FIMA. Although no TRISO coating failures were detected during the irradiation, the fraction of Ag-110m retained in individual particles often varied considerably within a single compact and at the capsule level. At the capsule level Ag-110m release fractions ranged from 1.2 to 38% and within a single compact, silver release from individual particles often spanned a range that extended from 100% retention to nearly 100% release. In this paper, selected irradiated particles from Baseline, Variant 1 and Variant 3 type fueled TRISO coated particles were examined using Scanning Electron Microscopy, Atom Probe Tomography; Electron Energy Loss Spectroscopy; Precession Electron Diffraction, Transmission Electron Microscopy, Scanning Transmission Electron Microscopy (STEM), High Resolution Electron Microscopy (HRTEM) examinations and Electron Probe Micro-Analyzer. Particle selection in this study allowed for comparison of the fission product distribution with Ag retention, fuel type and irradiation level. Nano sized Ag-containing features were predominantly identified in SiC grain boundaries and/or triple points in contrast with only two sitings of Ag inside a SiC grain in two different compacts (Baseline and Variant 3 fueled compacts). STEM and HRTEM analysis showed evidence of Ag and Pd co-existence in some cases and it was found that fission product precipitates can consist of multiple or single phases. STEM analysis also showed differences in precipitate compositions between Baseline and Variant 3 fuels. A higher density of fission product precipitate clusters were identified in the SiC layer in particles from the Variant 3 compact compared with the Variant 1 compact. Trend analysis shows

AGR-3/4 Final Data Qualification Report for ATR Cycles 151A through 155B-1

Energy Technology Data Exchange (ETDEWEB)

Pham, Binh T. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2015-03-01

This report provides the qualification status of experimental data for the entire Advanced Gas Reactor 3/4 (AGR 3/4) fuel irradiation. AGR-3/4 is the third in a series of planned irradiation experiments conducted in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) for the AGR Fuel Development and Qualification Program, which supports development of the advanced reactor technology under the INL ART Technology Development Office (TDO). The main objective of AGR-3/4 irradiation is to provide a known source of fission products for subsequent transport through compact matrix and structural graphite materials due to the presence of designed-to-fail fuel particles. Full power irradiation of the AGR 3/4 test began on December 14, 2011 (ATR Cycle 151A), and was completed on April 12, 2014 (end of ATR Cycle 155B) after 369.1 effective full power days of irradiation. The AGR-3/4 test was in the reactor core for eight of the ten ATR cycles between 151A and 155B. During the unplanned outage cycle, 153A, the experiment was removed from the ATR northeast flux trap (NEFT) location and stored in the ATR canal. This was to prevent overheating of fuel compacts due to higher than normal ATR power during the subsequent Powered Axial Locator Mechanism cycle, 153B. The AGR 3/4 test was inserted back into the ATR NEFT location during the outage of ATR Cycle 154A on April 26, 2013. Therefore, the AGR-3/4 irradiation data received during these 2 cycles (153A and 153B) are irrelevant and their qualification status isnot included in this report. Additionally, during ATR Cycle 152A the ATR core ran at low power for a short enough duration that the irradiation data are not used for physics and thermal calculations. However, the qualification status of irradiation data for this cycle is still covered in this report. As a result, this report includes data from 8 ATR Cycles: 151A, 151B, 152A, 152B, 154A, 154B, 155A, and 155B, as recorded in the Nuclear Data Management and

AGR-2 Irradiation Test Final As-Run Report, Rev 2

Energy Technology Data Exchange (ETDEWEB)

Collin, Blaise P. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2014-08-01

half calendar years. The test contained six independently controlled and monitored capsules. Each U.S. capsule contained 12 compacts of either UCO or UO2 AGR coated fuel. No fuel particles failed during the AGR-2 irradiation. Final burnup values on a per compact basis ranged from 7.26 to 13.15% FIMA (fissions per initial heavy-metal atom) for UCO fuel, and 9.01 to 10.69% FIMA for UO₂ fuel, while fast fluence values ranged from 1.94 to 3.47 x 10²⁵ n/m² (E >0.18 MeV) for UCO fuel, and from 3.05 to 3.53 x 10²⁵ n/m² (E >0.18 MeV) for UO₂ fuel. Time-average volume-average (TAVA) temperatures on a capsule basis at the end of irradiation ranged from 987°C in Capsule 6 to 1296°C in Capsule 2 for UCO, and from 996 to 1062°C in UO₂-fueled Capsule 3. By the end of the irradiation, all of the installed thermocouples (TCs) had failed. Fission product release-to-birth (R/B) ratios were quite low. In the UCO capsules, R/B values during the first three cycles were below 10^-6 with the exception of the hotter Capsule 2, in which the R/Bs reached 2 x 10^-6. In the UO₂ capsule (Capsule 3), the R/B values during the first three cycles were below 10^-7. R/B values for all following cycles are not reliable due to gas flow and cross talk issues.

AGR-2 Irradiated Test Train Preliminary Inspection and Disassembly First Look

Energy Technology Data Exchange (ETDEWEB)

Ploger, Scott [Idaho National Lab. (INL), Idaho Falls, ID (United States); Demkowciz, Paul [Idaho National Lab. (INL), Idaho Falls, ID (United States); Harp, Jason [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2015-05-01

The AGR 2 irradiation experiment began in June 2010 and was completed in October 2013. The test train was shipped to the Materials and Fuels Complex in July 2014 for post-irradiation examination (PIE). The first PIE activities included nondestructive examination of the test train, followed by disassembly of the test train and individual capsules and detailed inspection of the capsule contents, including the fuel compacts and their graphite fuel holders. Dimensional metrology was then performed on the compacts, graphite holders, and steel capsule shells. AGR 2 disassembly and metrology were performed with the same equipment used successfully on AGR 1 test train components. Gamma spectrometry of the intact test train gave a preliminary look at the condition of the interior components. No evidence of damage to compacts or graphite components was evident from the isotopic and gross gamma scans. Disassembly of the AGR 2 test train and its capsules was conducted rapidly and efficiently by employing techniques refined during the AGR 1 disassembly campaign. Only one major difficulty was encountered while separating the test train into capsules when thermocouples (of larger diameter than used in AGR 1) and gas lines jammed inside the through tubes of the upper capsules, which required new tooling for extraction. Disassembly of individual capsules was straightforward with only a few minor complications. On the whole, AGR 2 capsule structural components appeared less embrittled than their AGR 1 counterparts. Compacts from AGR 2 Capsules 2, 3, 5, and 6 were in very good condition upon removal. Only relatively minor damage or markings were visible using high resolution photographic inspection. Compact dimensional measurements indicated radial shrinkage between 0.8 to 1.7%, with the greatest shrinkage observed on Capsule 2 compacts that were irradiated at higher temperature. Length shrinkage ranged from 0.1 to 0.9%, with by far the lowest axial shrinkage on Capsule 3 compacts�

Determination of the Quantity of I-135 Released from the AGR Experiment Series

International Nuclear Information System (INIS)

Scates, Dawn M.; Walter, John B.; Reber, Edward L.; Sterbentz, James W.; Petti, David A.

2014-01-01

A series of three Advanced Gas Reactor (AGR) experiments have been conducted in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). From 2006 through 2014, these experiments supported the development and qualification of the new U.S. tri-structural isotropic (TRISO) particle fuel for Very High Temperature Reactors (VHTR). Each AGR experiment consisted of multiple fueled capsules, each plumbed for independent temperature control using a mix of helium and neon gases. The gas leaving a capsule was routed to individual Fission Product Monitor (FPM) detectors. For intact fuel particles, the TRISO particle coatings provide a substantial barrier to fission product release. However, particles with failed coatings, whether because of a minute percentage of initially defective particles, those which fail during irradiation, or those designed-to-fail (DTF) particles, can release fission products to the flowing gas stream. Because reactive fission product elements like iodine and cesium quickly deposit on cooler capsule components and piping structures as the effluent gas leaves the reactor core, only the noble fission gas isotopes of Kr and Xe tend to reach FPM detectors. The FPM system utilizes High Purity Germanium (HPGe) detectors coupled with a thallium activated sodium iodide NaI(Tl) scintillator. The germanium detector provides individual isotopic information, while the NaI(Tl) scintillator is used as a gross count rate meter. During irradiation, the "1"3"5"mXe concentration reaching the FPM detectors is from both direct fission and by decay of the accumulated "1"3"5I. About ~2.5 hours after irradiation (ten 15.3 minute "1"3"5mXe half-lives) the directly produced "1"3"5"mXe has decayed and only the longer lived "1"3"5I remains as a source. Decay systematics dictate that "1"3"5"mXe will be in secular equilibrium with its "1"3"5I parent, such that it’s production rate very nearly equals the decay rate of the parent, and its concentration in the flowing

AGR-2 Data Qualification Interim Report

International Nuclear Information System (INIS)

Abbott, Michael L.

2010-01-01

Projects for the very high temperature reactor (VHTR) Technology Development Office program provide data in support of Nuclear Regulatory Commission licensing of the VHTR. Fuel and materials to be used in the reactor are tested and characterized to quantify performance in high temperature and high fluence environments. The VHTR program established the NGNP Data Management and Analysis System (NDMAS) to manage and document VHTR data qualification, for storage of the data in a readily accessible electronic form, and to assist in the analysis and presentation of the data. This document gives the status of NDMAS processing and qualification of data associated with the initial reactor cycle (147A) of the second Advanced Gas Reactor (AGR-2) experiment which began on June 21, 2010. Because it is early in the AGR-2 experiment, data from only two AGR-2 data streams are reported on: Fuel Fabrication and Fuel Irradiation data. As of August 1, 2010, approximately 311,000 irradiation data records have been stored in NDMAS, and qualification tests are in progress. Preliminary information indicates that TC 2 in Capsule 2 failed prior to start of the experiment, and NDMAS testing has thus far identified only two invalid data values from the METSO data collection system Data from the Fission Product Monitoring System (FPMS) are not currently processed until after reactor cycle shutdown and have not yet been received. A description of the ATR operating conditions data associated with the AGR-2 experiment (e.g., power levels) are summarized in the AGR-1 data qualification report (INL/EXT-09-16460). Since ATR data are collected under ATR program data quality requirements (i.e., outside the VHTR program), the NGNP program and NDMAS do not take additional actions to qualify these data other than NDMAS capture testing. Data qualification of graphite characterization data collected under the Graphite Technology Development Project is reported in a separate status report (Hull 2010).

AGR-2 Data Qualification Interim Report

Energy Technology Data Exchange (ETDEWEB)

Michael L. Abbott

2010-09-01

Projects for the very high temperature reactor (VHTR) Technology Development Office program provide data in support of Nuclear Regulatory Commission licensing of the VHTR. Fuel and materials to be used in the reactor are tested and characterized to quantify performance in high temperature and high fluence environments. The VHTR program established the NGNP Data Management and Analysis System (NDMAS) to manage and document VHTR data qualification, for storage of the data in a readily accessible electronic form, and to assist in the analysis and presentation of the data. This document gives the status of NDMAS processing and qualification of data associated with the initial reactor cycle (147A) of the second Advanced Gas Reactor (AGR-2) experiment which began on June 21, 2010. Because it is early in the AGR-2 experiment, data from only two AGR-2 data streams are reported on: Fuel Fabrication and Fuel Irradiation data. As of August 1, 2010, approximately 311,000 irradiation data records have been stored in NDMAS, and qualification tests are in progress. Preliminary information indicates that TC 2 in Capsule 2 failed prior to start of the experiment, and NDMAS testing has thus far identified only two invalid data values from the METSO data collection system Data from the Fission Product Monitoring System (FPMS) are not currently processed until after reactor cycle shutdown and have not yet been received. A description of the ATR operating conditions data associated with the AGR-2 experiment (e.g., power levels) are summarized in the AGR-1 data qualification report (INL/EXT-09-16460). Since ATR data are collected under ATR program data quality requirements (i.e., outside the VHTR program), the NGNP program and NDMAS do not take additional actions to qualify these data other than NDMAS capture testing. Data qualification of graphite characterization data collected under the Graphite Technology Development Project is reported in a separate status report (Hull 2010).

AGR-2 Irradiation Test Final As-Run Report

Energy Technology Data Exchange (ETDEWEB)

Collin, Blaise P. [Idaho National Lab. (INL), Idaho Falls, ID (United States). VHTR Program

2014-08-01

This document presents the as-run analysis of the AGR-2 irradiation experiment. AGR-2 is the second of the planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. Funding for this program is provided by the U.S. Department of Energy as part of the Very High Temperature Reactor (VHTR) Technology Development Office (TDO) program. The objectives of the AGR-2 experiment are to: 1. Irradiate UCO (uranium oxycarbide) and UO₂ (uranium dioxide) fuel produced in a large coater. Fuel attributes are based on results obtained from the AGR-1 test and other project activities. 2. Provide irradiated fuel samples for post-irradiation experiment (PIE) and safety testing. 3. Support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. The primary objective of the test was to irradiate both UCO and UO₂ TRISO (tristructural isotropic) fuel produced from prototypic scale equipment to obtain normal operation and accident condition fuel performance data. The UCO compacts were subjected to a range of burnups and temperatures typical of anticipated prismatic reactor service conditions in three capsules. The test train also includes compacts containing UO₂ particles produced independently by the United States, South Africa, and France in three separate capsules. The range of burnups and temperatures in these capsules were typical of anticipated pebble bed reactor service conditions. The results discussed in this report pertain only to U.S.-produced fuel.

Comparison of silver release predictions using PARFUME with results from the AGR-2 irradiation experiment

Energy Technology Data Exchange (ETDEWEB)

Collin, Blaise P.; Demkowicz, Paul A.; Baldwin, Charles A.; Harp, Jason M.; Hunn, John D.

2016-11-01

The PARFUME (PARticle FUel ModEl) code was used to predict silver release from tristructural isotropic (TRISO) coated fuel particles and compacts during the second irradiation experiment (AGR-2) of the Advanced Gas Reactor Fuel Development and Qualification program. The PARFUME model for the AGR-2 experiment used the fuel compact volume average temperature for each of the 559 days of irradiation to calculate the release of fission product silver from a representative particle for a select number of AGR-2 compacts and individual fuel particles containing either mixed uranium carbide/oxide (UCO) or 100% uranium dioxide (UO2) kernels. Post-irradiation examination (PIE) measurements were performed to provide data on release of silver from these compacts and individual fuel particles. The available experimental fractional releases of silver were compared to their corresponding PARFUME predictions. Preliminary comparisons show that PARFUME under-predicts the PIE results in UCO compacts and is in reasonable agreement with experimental data for UO2 compacts. The accuracy of PARFUME predictions is impacted by the code limitations in the modeling of the temporal and spatial distributions of the temperature across the compacts. Nevertheless, the comparisons on silver release lie within the same order of magnitude.

Acceptance Test Data for Candidate AGR-5/6/7 TRISO Particle Batches BWXT Coater Batches 93165 93172 Defective IPyC Fraction and Pyrocarbon Anisotropy

Energy Technology Data Exchange (ETDEWEB)

Helmreich, Grant W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hunn, John D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Skitt, Darren J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dyer, John A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Schumacher, Austin T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-03-01

Coated particle fuel batches J52O-16-93165, 93166, 93168, 93169, 93170, and 93172 were produced by Babcock and Wilcox Technologies (BWXT) for possible selection as fuel for the Advanced Gas Reactor Fuel Development and Qualification (AGR) Program’s AGR-5/6/7 irradiation test in the Idaho National Laboratory (INL) Advanced Test Reactor (ATR). Some of these batches may alternately be used as demonstration coated particle fuel for other experiments. Each batch was coated in a 150-mm-diameter production-scale fluidized-bed chemical vapor deposition (CVD) furnace. Tristructural isotropic (TRISO) coatings were deposited on 425-μm-nominal-diameter spherical kernels from BWXT lot J52R-16-69317 containing a mixture of 15.5%-enriched uranium carbide and uranium oxide (UCO). The TRISO coatings consisted of four consecutive CVD layers: a ~50% dense carbon buffer layer with 100-μm-nominal thickness, a dense inner pyrolytic carbon (IPyC) layer with 40-μm-nominal thickness, a silicon carbide (SiC) layer with 35-μm-nominal thickness, and a dense outer pyrolytic carbon (OPyC) layer with 40-μmnominal thickness. The TRISO-coated particle batches were sieved to upgrade the particles by removing over-sized and under-sized material, and the upgraded batches were designated by appending the letter A to the end of the batch number (e.g., 93165A).

AGR-2 Irradiation Test Final As-Run Report

Energy Technology Data Exchange (ETDEWEB)

Collin, Blaise P. [Idaho National Lab. (INL), Idaho Falls, ID (United States). VHTR Program

2014-08-01

This document presents the as-run analysis of the AGR-2 irradiation experiment. AGR-2 is the second of the planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. Funding for this program is provided by the U.S. Department of Energy as part of the Very High Temperature Reactor (VHTR) Technical Development Office (TDO) program. The objectives of the AGR-2 experiment are to: (a) Irradiate UCO (uranium oxycarbide) and UO₂ (uranium dioxide) fuel produced in a large coater. Fuel attributes are based on results obtained from the AGR-1 test and other project activities. (b) Provide irradiated fuel samples for post-irradiation experiment (PIE) and safety testing. (c) Support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. The primary objective of the test was to irradiate both UCO and UO₂ TRISO (tri-structural isotropic) fuel produced from prototypic scale equipment to obtain normal operation and accident condition fuel performance data. The UCO compacts were subjected to a range of burnups and temperatures typical of anticipated prismatic reactor service conditions in three capsules. The test train also includes compacts containing UO₂ particles produced independently by the United States, South Africa, and France in three separate capsules. The range of burnups and temperatures in these capsules were typical of anticipated pebble bed reactor service conditions. The results discussed in this report pertain only to U.S. produced fuel.

Improving the AGR fuel testing power density profile versus irradiation-time in the advanced test reactor

International Nuclear Information System (INIS)

Chang, Gray S.; Lillo, Misti A.; Maki, John T.; Petti, David A.

2009-01-01

The Very High Temperature gas-cooled Reactor (VHTR), which is currently being developed, achieves simplification of safety through reliance on ceramic-coated fuel particles. Each TRISO-coated fuel particle has its own containment which serves as the principal barrier against radionuclide release under normal operating and accident conditions. These fuel particles, in the form of graphite fuel compacts, are currently undergoing a series of irradiation tests in the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) to support the Advanced Gas-Cooled Reactor (AGR) fuel qualification program. A representive coated fuel particle with an 235 U enrichment of 19.8 wt% was used in this analysis. The fuel burnup analysis tool used to perform the neutronics study reported herein, couples the Monte Carlo transport code MCNP, with the radioactive decay and burnup code ORIGEN2. The fuel burnup methodology known as Monte-Carlo with ORIGEN2 (MCWO) was used to evaluate the AGR experiment assembly and demonstrate compliance with ATR safety requirements. For the AGR graphite fuel compacts, the MCWO-calculated fission power density (FPD) due to neutron fission in 235 U is an important design parameter. One of the more important AGR fuel testing requirements is to maintain the peak fuel compact temperature close to 1250degC throughout the proposed irradiation campaign of 550 effective full power days (EFPDs). Based on the MCWO-calculated FPD, a fixed gas gap size was designed to allow regulation of the fuel compact temperatures throughout the entire fuel irradiation campaign by filling the gap with a mixture of helium and neon gases. The chosen fixed gas gap can only regulate the peak fuel compact temperature in the desired range during the irradiation test if the ratio of the peak power density to the time-dependent low power density (P/T) at 550 EFPDs is less than 2.5. However, given the near constant neutron flux within the ATR driver core and the depletion of 235 U

The Agr Quorum Sensing System Represses Persister Formation through Regulation of Phenol Soluble Modulins in Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Tao Xu

2017-11-01

Full Text Available The opportunistic pathogen Staphylococcus aureus has become an increasing threat to public health. While the Agr quorum sensing (QS system is a master regulator of S. aureus virulence, its dysfunction has been frequently reported to promote bacteremia and mortality in clinical infections. Here we show that the Agr system is involved in persister formation in S. aureus. Mutation of either agrCA or agrD but not RNAIII resulted in increased persister formation of stationary phase cultures. RNA-seq analysis showed that in stationary phase AgrCA/AgrD and RNAIII mutants showed consistent up-regulation of virulence associated genes (lip and splE, etc. and down-regulation of metabolism genes (bioA and nanK, etc.. Meanwhile, though knockout of agrCA or agrD strongly repressed expression of phenol soluble modulin encoding genes psmα1-4, psmβ1-2 and phenol soluble modulins (PSM transporter encoding genes in the pmt operon, mutation of RNAIII enhanced expression of the genes. We further found that knockout of psmα1-4 or psmβ1-2 augmented persister formation and that co-overexpression of PSMαs and PSMβs reversed the effects of AgrCA mutation on persister formation. We also detected the effects on persister formation by mutations of metabolism genes (arcA, hutU, narG, nanK, etc. that are potentially regulated by Agr system. It was found that deletion of the ManNAc kinase encoding gene nanK decreased persister formation. Taken together, these results shed new light on the PSM dependent regulatory role of Agr system in persister formation and may have implications for clinical treatment of MRSA persistent infections.

AgrAbility Project

Science.gov (United States)

... Cordless Ratchet Wrench ClampTite Wire Clamping Tool iBlue Smart Gate/Door Opener Full Toolbox AT Database Extranet ... in-person NTW - March 19-22, Portland, Maine House and Senate Appropriations Committees recommend restoring AgrAbility funding... ...

Progress with the AGR system

International Nuclear Information System (INIS)

Merrett, D.J.

1984-01-01

The AGR programme was initiated in 1965 with the ordering of the Dungeness 'B' reactor, followed by Hinkley point 'B' (1965), Hunterston 'B' (1968), Hartlepool (1970), Heysham I (1970) and the two latest stations at Heysham II and Torness. The paper reviews the achievements and prospects for the AGR system under 6 topic headings. These include: operational experience at Hinkley Point 'B' and Hunterston'B', commissioning of Dungeness 'B', Hartlepool and Heysham I, Heysham II/Torness design, Heysham II/Torness programme and finally future prospects. (U.K.)

An analysis of nuclear fuel burnup in the AGR-1 TRISO fuel experiment using gamma spectrometry, mass spectrometry, and computational simulation techniques

International Nuclear Information System (INIS)

Harp, Jason M.; Demkowicz, Paul A.; Winston, Philip L.; Sterbentz, James W.

2014-01-01

Highlights: • The burnup of irradiated AGR-1 TRISO fuel was analyzed using gamma spectrometry. • The burnup of irradiated AGR-1 TRISO fuel was also analyzed using mass spectrometry. • Agreement between experimental results and neutron physics simulations was excellent. - Abstract: AGR-1 was the first in a series of experiments designed to test US TRISO fuel under high temperature gas-cooled reactor irradiation conditions. This experiment was irradiated in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) and is currently undergoing post-irradiation examination (PIE) at INL and Oak Ridge National Laboratory. One component of the AGR-1 PIE is the experimental evaluation of the burnup of the fuel by two separate techniques. Gamma spectrometry was used to non-destructively evaluate the burnup of all 72 of the TRISO fuel compacts that comprised the AGR-1 experiment. Two methods for evaluating burnup by gamma spectrometry were developed, one based on the Cs-137 activity and the other based on the ratio of Cs-134 and Cs-137 activities. Burnup values determined from both methods compared well with the values predicted from simulations. The highest measured burnup was 20.1% FIMA (fissions per initial heavy metal atom) for the direct method and 20.0% FIMA for the ratio method (compared to 19.56% FIMA from simulations). An advantage of the ratio method is that the burnup of the cylindrical fuel compacts can be determined in small (2.5 mm) axial increments and an axial burnup profile can be produced. Destructive chemical analysis by inductively coupled mass spectrometry (ICP-MS) was then performed on selected compacts that were representative of the expected range of fuel burnups in the experiment to compare with the burnup values determined by gamma spectrometry. The compacts analyzed by mass spectrometry had a burnup range of 19.3% FIMA to 10.7% FIMA. The mass spectrometry evaluation of burnup for the four compacts agreed well with the gamma

AGR v PWR

International Nuclear Information System (INIS)

Green, D.

1986-01-01

When the Central Electricity Generating Board (CEGB) invited tenders and placed a contract for the Advanced Gas Cooled Reactor (AGR) at Dungeness B in 1965 -preferring it to the Pressurised Water Reactor (PWR) -the AGR was lamentably ill developed. The effects of the decision were widely felt, for it took the British nuclear industry off the light water reactor highway of world reactor business and up and idiosyncratic private highway of its own, excluding it altogether from any material export business in the two decades which followed. Yet although the UK may have made wrong decisions in rejecting the PWR in 1965, that does not mean that it can necessarily now either correct them, or redeem their consequence, by reversing the choice in 1985. In the 20 years since 1965 the whole world economic and energy picture has been transformed and the national picture with it. Picking up the PWR now could prove as big a disaster as rejecting it may have been in 1965. (author)

Description of the advanced gas cooled type of reactor (AGR)

Energy Technology Data Exchange (ETDEWEB)

Nonboel, E. [Risoe National Lab., Roskilde (Denmark)

1996-11-01

The present report comprises a technical description of the Advanced Gas cooled Reactor (AGR), a reactor type which has only been built in Great Britain. 14 AGR reactors have been built, located at 6 different sites and each station is supplied with twin-reactors. The Torness AGR plant on the Lothian coastline of Scotland, 60 km east of Edinburgh, has been chosen as the reference plant and is described in some detail. Data on the other 6 stations, Dungeness B, Hinkely Point B, Hunterston G, Hartlepool, Heysham I and Heysham II, are given only in tables with a summary of design data. Where specific data for Torness AGR has not been available, corresponding data from other AGR plans has been used, primarily from Heysham II, which belongs to the same generation of AGR reactors. The information presented is based on the open literature. The report is written as a part of the NKS/RAK-2 subproject 3: `Reactors in Nordic Surroundings`, which comprises a description of nuclear power plants neighbouring the Nordic countries. (au) 11 refs.

Description of the advanced gas cooled type of reactor (AGR)

International Nuclear Information System (INIS)

Nonboel, E.

1996-11-01

The present report comprises a technical description of the Advanced Gas cooled Reactor (AGR), a reactor type which has only been built in Great Britain. 14 AGR reactors have been built, located at 6 different sites and each station is supplied with twin-reactors. The Torness AGR plant on the Lothian coastline of Scotland, 60 km east of Edinburgh, has been chosen as the reference plant and is described in some detail. Data on the other 6 stations, Dungeness B, Hinkely Point B, Hunterston G, Hartlepool, Heysham I and Heysham II, are given only in tables with a summary of design data. Where specific data for Torness AGR has not been available, corresponding data from other AGR plans has been used, primarily from Heysham II, which belongs to the same generation of AGR reactors. The information presented is based on the open literature. The report is written as a part of the NKS/RAK-2 subproject 3: 'Reactors in Nordic Surroundings', which comprises a description of nuclear power plants neighbouring the Nordic countries. (au) 11 refs

Anterior Gradient 2 (AGR2) Induced Epidermal Growth Factor Receptor (EGFR) Signaling Is Essential for Murine Pancreatitis-Associated Tissue Regeneration

Science.gov (United States)

Wodziak, Dariusz; Dong, Aiwen; Basin, Michael F.; Lowe, Anson W.

2016-01-01

A recently published study identified Anterior Gradient 2 (AGR2) as a regulator of EGFR signaling by promoting receptor presentation from the endoplasmic reticulum to the cell surface. AGR2 also promotes tissue regeneration in amphibians and fish. Whether AGR2-induced EGFR signaling is essential for tissue regeneration in higher vertebrates was evaluated using a well-characterized murine model for pancreatitis. The impact of AGR2 expression and EGFR signaling on tissue regeneration was evaluated using the caerulein-induced pancreatitis mouse model. EGFR signaling and cell proliferation were examined in the context of the AGR2-/- null mouse or with the EGFR-specific tyrosine kinase inhibitor, AG1478. In addition, the Hippo signaling coactivator YAP1 was evaluated in the context of AGR2 expression during pancreatitis. Pancreatitis-induced AGR2 expression enabled EGFR translocation to the plasma membrane, the initiation of cell signaling, and cell proliferation. EGFR signaling and tissue regeneration were partially inhibited by the tyrosine kinase inhibitor AG1478, but absent in the AGR2-/- null mouse. AG1478-treated and AGR2-/- null mice with pancreatitis died whereas all wild-type controls recovered. YAP1 activation was also dependent on pancreatitis-induced AGR2 expression. AGR2-induced EGFR signaling was essential for tissue regeneration and recovery from pancreatitis. The results establish tissue regeneration as a major function of AGR2-induced EGFR signaling in adult higher vertebrates. Enhanced AGR2 expression and EGFR signaling are also universally present in human pancreatic cancer, which support a linkage between tissue injury, regeneration, and cancer pathogenesis. PMID:27764193

Saúde e mercado de trabalho no Brasil: diferenciais entre ocupados agrícolas e não agrícolas

Directory of Open Access Journals (Sweden)

Alexandre Gori Maia

2010-12-01

Full Text Available Este trabalho analisa as diferenças no estado de saúde entre e dentro dos grupos de ocupados agrícolas e não agrícolas no Brasil, utilizando medidas de autoavaliação do estado de saúde captadas no suplemento da PNAD (Pesquisa Nacional por Amostra de Domicílios de 2008. As análises baseiam-se na composição socioeconômica dos ocupados agrícolas e não agrícolas e nas estimativas de equações simultâneas para captar as relações não lineares entre saúde, renda e jornada de trabalho. Um dos pressupostos do trabalho é que a baixa prevalência de saudáveis entre os ocupados agrícolas estaria associada, sobretudo, à composição socioeconômica desse grupo, e não à maior insalubridade a que os ocupados das atividades agrícolas estariam submetidos em condições socioeconômicas semelhantes às dos não agrícolas. Analogamente, a desigualdade no estado de saúde seria menor entre os ocupados agrícolas devido aos hábitos mais homogêneos, não só no que se refere ao tipo de atividade, mas também em relação à qualidade de vida e ao acesso a uma série de itens de consumo, típico das localidades menos desenvolvidas onde as atividades agrícolas prevalecem.This paper analyzes differences of health conditions between and within agricultural and non-agricultural workers in Brazil. Self-reported health measures of the Health Supplement of Pesquisa Nacional por Amostra de Domicílios (PNAD, from 2008, are used. Results are based on the description of the socioeconomic characteristics of each group of employees and on estimates of a simultaneous equation to measure non-linear relations between health conditions, income and work hours. The main hypothesis is that the lower prevalence of workers with good health among agricultural workers is mainly due to socioeconomic characteristics of this group and not necessarily to higher insalubrious conditions that such workers would be submitted to in equivalent socioeconomic conditions

A formação de Licenciados em Ciências Agrícolas/Agrárias: o conhecimento e suas conexões

Directory of Open Access Journals (Sweden)

Marco Antonio de Moraes

2014-11-01

Full Text Available http://dx.doi.org/10.5902/1984644413683Este trabalho visa identificar os perfis de formação dos licenciados de Ciências Agrícolas/Agrárias e os objetivos dos cursos que formam estes profissionais no Brasil. Neste estudo exploratório, os dados foram coletados através da Internet no site do MEC e das Instituições de Ensino Superior. O perfil geralmente proposto na formação do professor em Ciências Agrícolas/Agrícolas é amplo, com atuação em diferentes campos das Ciências Agrárias com finalidades econômicas, mas com atenção às questões sócio-políticas e culturais presentes no meio rural brasileiro. Percebe-se a intenção de formar licenciados que atendam alguns aspectos ou demandas regionais e que estejam preparados para as questões da atualidade. Destaca-se a preocupação com o desenvolvimento de algumas competências importantes na formação do profissional que irá atuar na educação escolar.

SILICON CARBIDE GRAIN BOUNDARY DISTRIBUTIONS, IRRADIATION CONDITIONS, AND SILVER RETENTION IN IRRADIATED AGR-1 TRISO FUEL PARTICLES

Energy Technology Data Exchange (ETDEWEB)

Lillo, T. M.; Rooyen, I. J.; Aguiar, J. A.

2016-11-01

Precession electron diffraction in the transmission electron microscope was used to map grain orientation and ultimately determine grain boundary misorientation angle distributions, relative fractions of grain boundary types (random high angle, low angle or coincident site lattice (CSL)-related boundaries) and the distributions of CSL-related grain boundaries in the SiC layer of irradiated TRISO-coated fuel particles. Two particles from the AGR-1 experiment exhibiting high Ag-110m retention (>80%) were compared to a particle exhibiting low Ag-110m retention (<19%). Irradiated particles with high Ag-110m retention exhibited a lower fraction of random, high angle grain boundaries compared to the low Ag-110m retention particle. An inverse relationship between the random, high angle grain boundary fraction and Ag-110m retention is found and is consistent with grain boundary percolation theory. Also, comparison of the grain boundary distributions with previously reported unirradiated grain boundary distributions, based on SEM-based EBSD for similarly fabricated particles, showed only small differences, i.e. a greater low angle grain boundary fraction in unirradiated SiC. It was, thus, concluded that SiC layers with grain boundary distributions susceptible to Ag-110m release were present prior to irradiation. Finally, irradiation parameters were found to have little effect on the association of fission product precipitates with specific grain boundary types.

Mecanização Agrícola - Análise de aspectos de operacionalidade de máquinas agrícolas

OpenAIRE

Peça, José

2012-01-01

Este trabalho destina-se a apoiar a aprendizagem de estudantes do ramo das ciências agrárias sobre aspectos relevantes à operacionalidade das máquinas agrícolas. Utilização das equações de equilíbrio na previsão de esforços sobre os eixos de tractores com alfaias montadas e semi-montadas com vista a salvaguardar os limites técnicos, a estabilidade em declives e a qualidade do solo. Dada a importância que têm as operações de manuseamento de carga nas explorações agrícolas, é abordado o...

ATHENA optimized coating design

DEFF Research Database (Denmark)

Ferreira, Desiree Della Monica; Christensen, Finn Erland; Jakobsen, Anders Clemen

2012-01-01

The optimization of coating design for the ATHENA mission si described and the possibility of increasing the telescope effective area in the range between 0.1 and 10 keV is investigated. An independent computation of the on-axis effective area based on the mirror design of ATHENA is performed...... in order to review the current coating baseline. The performance of several material combinations, considering a simple bi-layer, simple multilayer and linear graded multilayer coatings are tested and simulation of the mirror performance considering both the optimized coating design and the coating...

Readiness Review of BWXT for Fabrication of AGR 5/6/7 Compacts

Energy Technology Data Exchange (ETDEWEB)

Marshall, Douglas William [Idaho National Lab. (INL), Idaho Falls, ID (United States); Sharp, Michelle Tracy [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2017-02-01

In support of preparations for fabricating compacts for the Advanced Gas Reactor (AGR) fuel qualification irradiation experiments (AGR-5/6/7), Idaho National Laboratory (INL) conducted a readiness review of the BWX Technology (BWXT) procedures, processes, and equipment associated with compact fabrication activities at the BWXT Nuclear Operations Group (BWXT-NOG) facility outside Lynchburg, VirginiaVA. The readiness review used quality assurance requirements taken from the American Society of Mechanical Engineers (ASME) Nuclear Quality Assurance Standard (NQA-1-2008/1a-2009) as a basis to assess readiness to start compact fabrication.

Survival of Listeria monocytogenes in Soil Requires AgrA-Mediated Regulation.

Science.gov (United States)

Vivant, Anne-Laure; Garmyn, Dominique; Gal, Laurent; Hartmann, Alain; Piveteau, Pascal

2015-08-01

In a recent paper, we demonstrated that inactivation of the Agr system affects the patterns of survival of Listeria monocytogenes (A.-L. Vivant, D. Garmyn, L. Gal, and P. Piveteau, Front Cell Infect Microbiol 4:160, http://dx.doi.org/10.3389/fcimb.2014.00160). In this study, we investigated whether the Agr-mediated response is triggered during adaptation in soil, and we compared survival patterns in a set of 10 soils. The fate of the parental strain L. monocytogenes L9 (a rifampin-resistant mutant of L. monocytogenes EGD-e) and that of a ΔagrA deletion mutant were compared in a collection of 10 soil microcosms. The ΔagrA mutant displayed significantly reduced survival in these biotic soil microcosms, and differential transcriptome analyses showed large alterations of the transcriptome when AgrA was not functional, while the variations in the transcriptomes between the wild type and the ΔagrA deletion mutant were modest under abiotic conditions. Indeed, in biotic soil environments, 578 protein-coding genes and an extensive repertoire of noncoding RNAs (ncRNAs) were differentially transcribed. The transcription of genes coding for proteins involved in cell envelope and cellular processes, including the phosphotransferase system and ABC transporters, and proteins involved in resistance to antimicrobial peptides was affected. Under sterilized soil conditions, the differences were limited to 86 genes and 29 ncRNAs. These results suggest that the response regulator AgrA of the Agr communication system plays important roles during the saprophytic life of L. monocytogenes in soil. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

AGR fuel management using PANTHER

International Nuclear Information System (INIS)

Haddock, S.A.; Parks, G.T.

1995-01-01

This paper describes recent improvements in the AGR fuel management methodology implemented within PANTHER and the use of the code both for stand-alone calculations and within an automatic optimisation procedure. (author)

Uncertainty Quantification of Calculated Temperatures for the AGR 3/4 Experiment

International Nuclear Information System (INIS)

Pham, Binh Thi-Cam

2015-01-01

A series of Advanced Gas Reactor (AGR) irradiation experiments are being conducted within the Advanced Reactor Technology (ART) Fuel Development and Qualification Program. The main objectives of the fuel experimental campaign are to provide the necessary data on fuel performance to support fuel process development, qualify a fuel design and fabrication process for normal operation and accident conditions, and support development and validation of fuel performance and fission product transport models and codes (PLN 3636, 'Technical Program Plan for INL Advanced Reactor Technologies Technology Development Office/Advanced Gas Reactor Fuel Development and Qualification Program'). The AGR 3/4 test was inserted in the Northeast Flux Trap position in the Advanced Test Reactor (ATR) core at Idaho National Laboratory (INL) in December 2011 and successfully completed irradiation in mid-April 2014, resulting in irradiation of the tristructural isotropic (TRISO) fuel for 369.1 effective full-power days (EFPDs) during approximately 2.4 calendar years. The AGR 3/4 data, including the irradiation data and calculated results, were qualified and stored in the Nuclear Data Management and Analysis System (NDMAS). To support the U.S. TRISO fuel performance assessment and to provide data for validation of fuel performance and fission product transport models and codes, the daily as run thermal analysis has been performed separately on each of twelve AGR 3/4 capsules for the entire irradiation as discussed in ECAR-2807, 'AGR 3/4 Daily As Run Thermal Analyses'. The ABAQUS code's finite element-based thermal model predicts the daily average volume average (VA) fuel temperature (FT), peak FT, and graphite matrix, sleeve, and sink temperature in each capsule. The JMOCUP simulation codes were also created to perform depletion calculations for the AGR 3/4 experiment (ECAR-2753, 'JMOCUP As-Run Daily Physics Depletion Calculation for the AGR 3/4 TRISO Particle

Uncertainty Quantification of Calculated Temperatures for the AGR 3/4 Experiment

Energy Technology Data Exchange (ETDEWEB)

Pham, Binh Thi-Cam [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2015-09-01

A series of Advanced Gas Reactor (AGR) irradiation experiments are being conducted within the Advanced Reactor Technology (ART) Fuel Development and Qualification Program. The main objectives of the fuel experimental campaign are to provide the necessary data on fuel performance to support fuel process development, qualify a fuel design and fabrication process for normal operation and accident conditions, and support development and validation of fuel performance and fission product transport models and codes (PLN 3636, “Technical Program Plan for INL Advanced Reactor Technologies Technology Development Office/Advanced Gas Reactor Fuel Development and Qualification Program”). The AGR 3/4 test was inserted in the Northeast Flux Trap position in the Advanced Test Reactor (ATR) core at Idaho National Laboratory (INL) in December 2011 and successfully completed irradiation in mid-April 2014, resulting in irradiation of the tristructural isotropic (TRISO) fuel for 369.1 effective full-power days (EFPDs) during approximately 2.4 calendar years. The AGR 3/4 data, including the irradiation data and calculated results, were qualified and stored in the Nuclear Data Management and Analysis System (NDMAS). To support the U.S. TRISO fuel performance assessment and to provide data for validation of fuel performance and fission product transport models and codes, the daily as run thermal analysis has been performed separately on each of twelve AGR 3/4 capsules for the entire irradiation as discussed in ECAR-2807, “AGR 3/4 Daily As Run Thermal Analyses”. The ABAQUS code’s finite element-based thermal model predicts the daily average volume average (VA) fuel temperature (FT), peak FT, and graphite matrix, sleeve, and sink temperature in each capsule. The JMOCUP simulation codes were also created to perform depletion calculations for the AGR 3/4 experiment (ECAR-2753, “JMOCUP As-Run Daily Physics Depletion Calculation for the AGR 3/4 TRISO Particle Experiment in ATR

Scottish Nuclear Limited: the AGR - past, present and future

International Nuclear Information System (INIS)

Anderson, D.; Barnes, G.G.

1993-01-01

This article reviews the historical development of the AGR (advanced gas-cooled reactor) in Scotland from its inception to its current successfully established position. It examines where the AGRs will go in the future and concludes with the strategic role of the existing and new plant in the market-led electricity supply industry. (Author)

Crystal Structure of AGR_C_4470p from Agrobacterium tumefaciens

Energy Technology Data Exchange (ETDEWEB)

Vorobiev,S.; Neely, H.; Seetharaman, J.; Ma, L.; Xiao, R.; Acton, T.; Montelione, G.; Tong, L.

2007-01-01

We report here the crystal structure at 2.0 {angstrom} resolution of the AGR{_}C{_}4470p protein from the Gram-negative bacterium Agrobacterium tumefaciens. The protein is a tightly associated dimer, each subunit of which bears strong structural homology with the two domains of the heme utilization protein ChuS from Escherichia coli and HemS from Yersinia enterocolitica. Remarkably, the organization of the AGR{_}C{_}4470p dimer is the same as that of the two domains in ChuS and HemS, providing structural evidence that these two proteins evolved by gene duplication. However, the binding site for heme, while conserved in HemS and ChuS, is not conserved in AGR{_}C{_}4470p, suggesting that it probably has a different function. This is supported by the presence of two homologs of AGR{_}C{_}4470p in E. coli, in addition to the ChuS protein.

AGR core safety assessment methodologies

International Nuclear Information System (INIS)

McLachlan, N.; Reed, J.; Metcalfe, M.P.

1996-01-01

To demonstrate the safety of its gas-cooled graphite-moderated AGR reactors, nuclear safety assessments of the cores are based upon a methodology which demonstrates no component failures, geometrical stability of the structure and material properties bounded by a database. All AGRs continue to meet these three criteria. However, predictions of future core behaviour indicate that the safety case methodology will eventually need to be modified to deal with new phenomena. A new approach to the safety assessment of the cores is currently under development, which can take account of these factors while at the same time providing the same level of protection for the cores. This approach will be based on the functionality of the core: unhindered movement of control rods, continued adequate cooling of the fuel and the core, continued ability to charge and discharge fuel. (author). 5 figs

AGR fuel pin pellet-clad interaction failure limits and activity release fractions

International Nuclear Information System (INIS)

Hughes, H.; Hargreaves, R.

1985-01-01

The limiting conditions beyond which pellet-clad interaction can flail AGR fuel are described. They have been determined by many experiments involving post-irradiation examination and testing, loop experiments and cycling and up-rating of both individual fuel stringers and the whole WAGR core. The mechanisms causing this interaction are well understood and are quantitatively expressed in computer codes. Strain concentration effects over fuel cracks determine power cycling endurance while additional strain concentrations at clad ridges and from cross pin temperature gradients contribute to up-rating failures. An equation summarising tube burst test data so as to determine the ductility available at any transient is given. The hollow fuel and more ductile clad of the Civil AGR fuel pins leads to a much improved performance over the original fuel design. The Civil AGRs operate well within these limiting conditions and substantial increases beyond the design burn-up are confidently expected. The activity release on pin failure and its development during continued operation of failed fuel have also been investigated. A retention of radioiodine and caesium of 90-99% compared to the noble gases has been demonstrated. Measured fission gas releases into the free volume of Civil AGR fuel pins have been very low (< 0.1%)

La Elvira, desarrollo agrícola olvidado (caso real

Directory of Open Access Journals (Sweden)

Álvaro Camacho Caicedo

2007-01-01

Full Text Available En éste artículo, se hace una reflexión crítica sobre la concepción que tradicionalmente han tenido los lideres y dirigentes de las instituciones gubernamentales, privadas y académicas relacionadas con el Desarrollo Rural del Municipio, sobre la importancia de "la contribución del "subsector agrícola campesino caleño" al PIB municipal. Se resalta la relación fundamental que existe entre el nivel de productividad y competitividad que pueden llegar a alcanzar los corregimientos caleños en sus cosechas de hortalizas con los acompañamientos, fomento y apoyos de asistencia tecnológica, crédito agrícola, administración de cultivos y comercialización por parte de las instituciones mencionadas. La falta de apoyos interinstitucionales genera en la comunidad el efecto contrario. En el presente artículo se plantean propuestas, estrategias y políticas para el desarrollo agrícola del corregimiento caleño de La Elvira, basadas en la experiencia del autor como economista agrícola y de otras personas interesadas y conocedoras del tema.

Endothelial function in children with white-coat hypertension.

Science.gov (United States)

Jurko, Alexander; Jurko, Tomas; Minarik, Milan; Mestanik, Michal; Mestanikova, Andrea; Micieta, Vladimir; Visnovcova, Zuzana; Tonhajzerova, Ingrid

2018-01-29

Several studies have demonstrated endothelial dysfunction in patients with essential hypertension. However, the presence of endothelial dysfunction in children with white-coat hypertension has not been studied. We evaluated the endothelial function in children with white-coat hypertension and essential hypertension using a novel method based on the assessment of flow-mediated dilation (FMD). Study involved 106 children: 30 white-coat hypertensives (age 16.3 ± 1.3 years, mean ± SD), 30 essential hypertensives (age 16.4 ± 1.3 years), and 46 healthy controls (age 16.2 ± 1.4 years). Ultrasound scans of the right brachial artery were performed using Prosound F75 Aloka system during protocol: baseline (1 min), forearm ischemia (5 min), and post-occlusion phase (3 min). FMD (%) was expressed as a change of the arterial diameter from baseline to maximum post-occlusion value and the values coat hypertension compared to control group (p coat hypertensives compared to controls (p coat hypertension could help to elucidate the mechanisms of the increased cardiovascular risk that could be similar as found in essential hypertension; therefore, white-coat hypertension should not be considered a benign phenomenon.

Corrosion inhibition studies in support of the long term storage of AGR fuel

Energy Technology Data Exchange (ETDEWEB)

Standring, P [Sellafield Limited (United Kingdom)

2012-07-01

Thorp Receipt and Storage (at Sellafield, UK) is currently being investigated as a bridging solution for the storage of AGR fuel pending the out-come of a national review into spent fuel management. AGR spent fuel is known to be susceptible to corrosion through inter-granular attack. To avoid this, the chosen storage regime for AGR fuel is sodium hydroxide dosed pond water to pH 11.4; now 22 years of operating experience. The conversion of TR and S will require a phased transition. During this transition sodium hydroxide cannot be used due to materials compatibility issues. Alternative corrosion inhibitors have been investigated as an interim measure and sodium nitrate has been selected as a suitable candidate. The efficiency of sodium nitrate to inhibit propagating inter-granular attack of active AGR materials has yet to be established. In the longer term sodium hydroxide will be deployed along with a move to a closed loop pond water management system. Given that carbon dioxide is known to be absorbed by sodium hydroxide dosed water and can affect fuel integrity, in the case of Magnox fuel, there is a need to establish its impact on AGR fuel. The objectives are: To establish the impact of carbonate on AGR fuel corrosion; To establish the efficiency of sodium nitrate to inhibit propagating inter-granular attack of irradiated AGR materials.

Saberes agrícolas tradicionales como programa académico

Directory of Open Access Journals (Sweden)

J. Antonio Gómez Espinoza

2008-01-01

Full Text Available En el marco de las crisis social y ambiental del tercer milenio, se hace necesario repensar la universidad, sus paradigmas, el concepto de educación y su modelo educativo para impactar en la construcción de la nueva sociedad. Los Saberes Agrícolas Tradicionales (SAT aportan elementos conceptuales básicos para la implementación y desarrollo de una sociedad sustentable. A partir del rescate, la sistematización de los SAT y el diálogo intercultural SAT-ciencia, se propone incorporar los Saberes Agrícolas Tradicionales como programa académico en las Instituciones de Enseñanza y Aprendizaje Agrícola del nivel Superior (IEAS.

Advances in AGR fuel fabrication - now and the future

International Nuclear Information System (INIS)

Bleasdale, P.A.

1995-01-01

To date, over 3 million AGR fuel pins have been manufactured at Springfields for the UK AGR programme. During this time, AGR fuel design and manufacture has developed and evolved in response to the needs of the reactor operators to enhance fuel reliability and performance. More recently, major advances have been made in the systems and organisational culture which support fuel manufacture at Fuel Division. The introduction of MRP II in 1989 into Fuel Division enabled significant reductions in stock and work-in-progress, together with reductions in manufacturing lead times. Other successful initiatives introduced into Fuel Division have been Just-in-Time (JIT) and AST (Additional Skills Training) which have built on the success of MRP II. All of these initiatives are evidence of Fuel Division's ''Total Quality'' approach to fabricating fuel. Fuel Division is currently in the final stages of commissioning the New Oxide Fuels Complex (NOFC) where both AGR and PWR fuel will be manufactured to the highest standards of quality, safety and environmental protection. NOFC is a totally integrated plant which represents a Pound 200M investment, demonstrating Fuel Division's commitment to building on its 40+ years of fuel fabrication experience and ensuring secure supply of fuel to its customers for years to come. (author)

Acceptance Test Data for BWXT Coated Particle Batch 93164A Defective IPyC Fraction and Pyrocarbon Anisotropy

Energy Technology Data Exchange (ETDEWEB)

Helmreich, Grant W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hunn, John D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Skitt, Darren J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dyer, John A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-02-01

Coated particle fuel batch J52O-16-93164 was produced by Babcock and Wilcox Technologies (BWXT) for possible selection as fuel for the Advanced Gas Reactor Fuel Development and Qualification (AGR) Program’s AGR-5/6/7 irradiation test in the Idaho National Laboratory (INL) Advanced Test Reactor (ATR), or may be used as demonstration production-scale coated particle fuel for other experiments. The tristructural-isotropic (TRISO) coatings were deposited in a 150-mm-diameter production-scale fluidizedbed chemical vapor deposition (CVD) furnace onto 425-μm-nominal-diameter spherical kernels from BWXT lot J52L-16-69316. Each kernel contained a mixture of 15.5%-enriched uranium carbide and uranium oxide (UCO) and was coated with four consecutive CVD layers: a ~50% dense carbon buffer layer with 100-μm-nominal thickness, a dense inner pyrolytic carbon (IPyC) layer with 40-μm-nominal thickness, a silicon carbide (SiC) layer with 35-μm-nominal thickness, and a dense outer pyrolytic carbon (OPyC) layer with 40-μm-nominal thickness. The TRISO-coated particle batch was sieved to upgrade the particles by removing over-sized and under-sized material, and the upgraded batch was designated by appending the letter A to the end of the batch number (i.e., 93164A).

The Staphylococcus aureus Two-Component System AgrAC Displays Four Distinct Genomic Arrangements That Delineate Genomic Virulence Factor Signatures

Directory of Open Access Journals (Sweden)

Kumari S. Choudhary

2018-05-01

Full Text Available Two-component systems (TCSs consist of a histidine kinase and a response regulator. Here, we evaluated the conservation of the AgrAC TCS among 149 completely sequenced Staphylococcus aureus strains. It is composed of four genes: agrBDCA. We found that: (i AgrAC system (agr was found in all but one of the 149 strains, (ii the agr positive strains were further classified into four agr types based on AgrD protein sequences, (iii the four agr types not only specified the chromosomal arrangement of the agr genes but also the sequence divergence of AgrC histidine kinase protein, which confers signal specificity, (iv the sequence divergence was reflected in distinct structural properties especially in the transmembrane region and second extracellular binding domain, and (v there was a strong correlation between the agr type and the virulence genomic profile of the organism. Taken together, these results demonstrate that bioinformatic analysis of the agr locus leads to a classification system that correlates with the presence of virulence factors and protein structural properties.

The Staphylococcus aureus Two-Component System AgrAC Displays Four Distinct Genomic Arrangements That Delineate Genomic Virulence Factor Signatures

Science.gov (United States)

Choudhary, Kumari S.; Mih, Nathan; Monk, Jonathan; Kavvas, Erol; Yurkovich, James T.; Sakoulas, George; Palsson, Bernhard O.

2018-01-01

Two-component systems (TCSs) consist of a histidine kinase and a response regulator. Here, we evaluated the conservation of the AgrAC TCS among 149 completely sequenced Staphylococcus aureus strains. It is composed of four genes: agrBDCA. We found that: (i) AgrAC system (agr) was found in all but one of the 149 strains, (ii) the agr positive strains were further classified into four agr types based on AgrD protein sequences, (iii) the four agr types not only specified the chromosomal arrangement of the agr genes but also the sequence divergence of AgrC histidine kinase protein, which confers signal specificity, (iv) the sequence divergence was reflected in distinct structural properties especially in the transmembrane region and second extracellular binding domain, and (v) there was a strong correlation between the agr type and the virulence genomic profile of the organism. Taken together, these results demonstrate that bioinformatic analysis of the agr locus leads to a classification system that correlates with the presence of virulence factors and protein structural properties. PMID:29887846

Caracterização dos acidentes com tratores agrícolas

Directory of Open Access Journals (Sweden)

Schlosser José Fernando

2002-01-01

Full Text Available Em despeito à sua importância, poucas pesquisas vêm sendo executadas com o intuito de caracterizar os acidentes de trabalho com tratores agrícolas, identificando sua natureza (tipo bem como suas causas. O objetivo deste trabalho foi caracterizar os acidentes envolvendo tratores agrícolas ocorridos na região da Depressão Central do Rio Grande do Sul e, a partir disto, delinear estratégias eficientes na sua prevenção. Para o levantamento dos dados, foi aplicado um questionário aos operadores de tratores agrícolas da região da Depressão Central do Rio Grande do Sul. Os dados demonstraram que 39% dos trabalhadores rurais entrevistados já sofreram algum tipo de acidente de trabalho com tratores agrícolas. Dentre os tipos de acidentes com tratores agrícolas detectados na pesquisa, destacam-se o capotamento, que correspondeu a 51,71% do total de acidentes graves, e os escorregões, que corresponderam a 40,82% dos acidentes leves. As principais causas dos acidentes relatados foram a falta de conhecimento a respeito das medidas de segurança na operação de tratores (32,77%, a falta de atenção (32,22% para a tarefa executada e o equipamento inadequado (22,22%. Os acidentes graves tiveram causas diferentes comparativamente aos leves. Operadores sem treinamento adequado, a não observação de regras básicas de segurança e a longa jornada de trabalho são tendências observadas neste trabalho que ampliam os riscos de ocorrência de acidentes. A inclusão de dispositivos que tornem a máquina mais segura e confortável, bem como o treinamento dos operadores de tratores agrícolas são práticas de importância fundamental para a prevenção dos acidentes com tratores agrícolas.

Acceptance Test Data for BWXT Coated Particle Batches 93172B and 93173B—Defective IPyC and Pyrocarbon Anisotropy

Energy Technology Data Exchange (ETDEWEB)

Hunn, John D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Helmreich, Grant W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dyer, John A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Schumacher, Austin T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Skitt, Darren J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-08-01

Coated particle batches J52O-16-93172B and J52O-16-93173B were produced by Babcock and Wilcox Technologies (BWXT) as part of the production campaign for the Advanced Gas Reactor Fuel Development and Qualification (AGR) Program’s AGR-5/6/7 irradiation test in the Idaho National Laboratory (INL) Advanced Test Reactor (ATR), but were not used in the final fuel composite. However, these batches may be used as demonstration production-scale coated particle fuel for other experiments. Each batch was coated in a 150-mm-diameter production-scale fluidized-bed chemical vapor deposition (CVD) furnace. Tristructural isotropic (TRISO) coatings were deposited on 425-μm-nominal-diameter spherical kernels from BWXT lot J52R-16-69317 containing a mixture of 15.5%-enriched uranium carbide and uranium oxide (UCO). The TRISO coatings consisted of four consecutive CVD layers: a ~50% dense carbon buffer layer with 100-μm-nominal thickness, a dense inner pyrolytic carbon (IPyC) layer with 40-μm-nominal thickness, a silicon carbide (SiC) layer with 35-μm-nominal thickness, and a dense outer pyrolytic carbon (OPyC) layer with 40-μm-nominal thickness. The TRISO-coated particle batches were sieved to upgrade the particles by removing over-sized and under-sized material, and the upgraded batches were designated by appending the letter A to the end of the batch number (e.g., 93172A). Secondary upgrading by sieving was performed on the A-designated batches to remove particles with missing or very-thin buffer layers that were identified during previous analysis of the individual batches for defective IPyC, as reported in the acceptance test data report for the AGR-5/6/7 production batches [Hunn et al. 2017b]. The additionally-upgraded batches were designated by appending the letter B to the end of the batch number (e.g., 93172B).

Trabajadores agrícolas y subjetividad en California

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Florencio Posadas Segura

2014-01-01

Full Text Available En este trabajo se explora el problema de la subjetividad de los trabajadores agríco - las, partiendo de la hipótesis de que éstos consideran malas sus condiciones de vida y de trabajo. Mediante el trabajo de campo se demostraron sus conocimientos y opi - niones sobre su situación laboral y existencial en el Valle de San Joaquín California durante 2007 y 2008. Se descubrió que la visión del trabajador agrícola está basada en la subjetivación y reinterpretación de sus circunstancias objetivas de trabajo y de vida. Se concluyó que los trabajadores agrícolas opinan que sus condiciones son pé - simas porque sus derechos laborales, sociales y humanos no se reconocen o respetan, la crisis económica, social y política de Estados Unidos les perjudica y el Tratado de Libre Comercio entre México, Estados Unidos y Canadá ( TLCAN sólo podría beneficiarles con una reforma migratoria.

CryoSat SAR/SARin Level1b products: assessment of BaselineC and improvements towards BaselineD

Science.gov (United States)

Scagliola, Michele; Fornari, Marco; Bouffard, Jerome; Parrinello, Tommaso

2017-04-01

CryoSat was launched on the 8th April 2010 and is the first European ice mission dedicated to the monitoring of precise changes in the thickness of polar ice sheets and floating sea ice. Cryosat carries an innovative radar altimeter called the Synthetic Aperture Interferometric Altimeter (SIRAL), that transmits pulses at a high pulse repetition frequency thus making the received echoes phase coherent and suitable for azimuth processing. This allows to reach a significantly improved along track resolution with respect to traditional pulse-width limited altimeters. CryoSat is the first altimetry mission operating in SAR mode and continuous improvements in the Level1 Instrument Processing Facility (IPF1) are being identified, tested and validated in order to improve the quality of the Level1b products. The current IPF, Baseline C, was released in operation in April 2015 and the second CryoSat reprocessing campaign was jointly initiated, taking benefit of the upgrade implemented in the IPF1 processing chain but also of some specific configurations for the calibration corrections. In particular, the CryoSat Level1b BaselineC products generated in the framework of the second reprocessing campaign include refined information for what concerns the mispointing angles and the calibration corrections. This poster will thus detail thus the evolutions that are currently planned for the CryoSat BaselineD SAR/SARin Level1b products and the corresponding quality improvements that are expected.

The design and development of AGR fuelling machines

International Nuclear Information System (INIS)

Calnan, J.P.; Hardon, L.

1986-01-01

The main functional requirements and essential generic design aspects of the UK AGR fuelling machines are listed and described as a precursor to reviewing some detail features of the individual station designs. The paper highlights the variability of engineering solutions adopted to meet the common challenge of on-load refuelling the first generation AGR stations. Design development from first to second generation stations is illustrated by detailed reference to the Hinkley B/Hunterston B and Heysham II/Torness fuelling machine designs. The paper concludes with a brief speculative view on the possible direction of future design development. (author)

AGR-2 Data Qualification Report for ATR Cycles 147A, 148A, 148B, and 149A

International Nuclear Information System (INIS)

Abbott, Michael L.; Daum, Keith A.

2011-01-01

This report presents the data qualification status of fuel irradiation data from the first four reactor cycles (147A, 148A, 148B, and 149A) of the on-going second Advanced Gas Reactor (AGR-2) experiment as recorded in the NGNP Data Management and Analysis System (NDMAS). This includes data received by NDMAS from the period June 22, 2010 through May 21, 2011. AGR-2 is the second in a series of eight planned irradiation experiments for the AGR Fuel Development and Qualification Program, which supports development of the very high temperature gas-cooled reactor (VHTR) under the Next Generation Nuclear Plant (NGNP) Project. Irradiation of the AGR-2 test train is being performed at the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) and is planned for 600 effective full power days (approximately 2.75 calendar years) (PLN-3798). The experiment is intended to demonstrate the performance of UCO (uranium oxycarbide) and UO2 (uranium dioxide) fuel produced in a large coater. Data qualification status of the AGR-1 experiment was reported in INL/EXT-10-17943 (Abbott et al. 2010).

AGR-2 Data Qualification Report for ATR Cycles 147A, 148A, 148B, and 149A

Energy Technology Data Exchange (ETDEWEB)

Michael L. Abbott; Keith A. Daum

2011-08-01

This report presents the data qualification status of fuel irradiation data from the first four reactor cycles (147A, 148A, 148B, and 149A) of the on-going second Advanced Gas Reactor (AGR-2) experiment as recorded in the NGNP Data Management and Analysis System (NDMAS). This includes data received by NDMAS from the period June 22, 2010 through May 21, 2011. AGR-2 is the second in a series of eight planned irradiation experiments for the AGR Fuel Development and Qualification Program, which supports development of the very high temperature gas-cooled reactor (VHTR) under the Next Generation Nuclear Plant (NGNP) Project. Irradiation of the AGR-2 test train is being performed at the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) and is planned for 600 effective full power days (approximately 2.75 calendar years) (PLN-3798). The experiment is intended to demonstrate the performance of UCO (uranium oxycarbide) and UO2 (uranium dioxide) fuel produced in a large coater. Data qualification status of the AGR-1 experiment was reported in INL/EXT-10-17943 (Abbott et al. 2010).

Competencias Profesionales del Ingeniero Agrónomo de la Universidad de Guanajuato Competencias Profesionales del Ingeniero Agrónomo de la Universidad de Guanajuato

Directory of Open Access Journals (Sweden)

Gabriel Córdova Duarte

2012-02-01

Full Text Available Buscando determinar las competencias profesionales del Ingeniero Agrónomo, se realizó una revisión bibliográfi ca de la problemática agrícola del estado de Guanajuato, sobre las características y tipos de competencias, requeridas en éste contexto. Las mismas se identificaron y clasificaron de la siguiente manera: técnicas, establecer, implementar y evaluar las diversas técnicas de producción de cultivos; realizar un uso eficiente del agua; conservar, recuperar y optimizar el suelo; seleccionar y manejar maquinaria y equipo agropecuario; diagnosticar, controlar y prevenir las plagas, malezas y enfermedades de los cultivos; las metodológicas: analizar, implementar y evaluar diversas estrategias de venta y comercialización de productos y subproductos agrícolas; administrar empresas y proyectos agrícolas; y, establecer, implementar y evaluar alternativas energéticas agrícolas; la social participativa: diseñar, implementar y evaluar diversas estrategias para el desarrollo rural. Por tanto, la formación del agrónomo debe brindar estas competencias, a fin de contribuir al mejoramiento de la problemática estatal. In order to determine the professional competencies needed by Agricultural Engineers, a bibliographic review of agricultural problems in the state of Guanajuato was performed, focused on the types and characteristics of competencies needed, which were identified and classified as follows: Techniques for the establishment, implementation, and evaluation of various methods of crop production; the efficient use of water; the conservation, recuperation, and optimization of soil; the selection and use of machinery and farming equipment; and the diagnosing, control, and prevention of weeds, vermin, and crop diseases; Methodologies for the analysis, implementation, and evaluation of various sales strategies and the commercialization of agricultural products and sub-products; the administration of companies and agricultural

Potencial de uso agrícola e nutricional de cultivares crioulas de feijão Cropping and nutritional potential of common bean land varieties

Directory of Open Access Journals (Sweden)

Nerinéia Dalfollo Ribeiro

2008-06-01

Full Text Available O valor nutricional e o potencial de uso agrícola de cultivares crioulas de feijão não têm sido suficientemente avaliados, sendo este o objetivo deste trabalho. O experimento foi conduzido nos anos agrícolas 2004/05 e 2005/06, em Santa Maria, RS, no delineamento experimental de látice triplo 6 x 6. Os tratamentos consistiram de 32 cultivares crioulas de feijão e quatro cultivares desenvolvidas pela pesquisa. Interação cultivar x ano foi observada em relação ao rendimento de grãos, à coloração do tegumento dos grãos e ao ciclo, evidenciando resposta diferenciada das cultivares crioulas aos anos de avaliação. Foi possível a identificação de cultivares crioulas com elevado potencial de rendimento de grãos, com coloração de tegumento de grãos adequada para os diferentes grupos comerciais, com precocidade e teor elevado de fibra alimentar. Nesse sentido, as cultivares crioulas - "21 INT-ps 1", "9 BR-ps 5", "9 BR-ps 15", "9 BR-ps 13", "9 BR-ps 7", "38 MO M-ps 11" e "36 BR MP-ps 14" - são promissoras para uso em programas de melhoramento genético devido ao elevado potencial de uso agrícola. A cultivar crioula "24 OP-ps 1" apresentou o maior teor de fibra alimentar e o seu potencial de uso como alimento funcional deve ser investigado.The objective of this study was to evaluate the nutrition and the crop values of common bean land varieties. The experiments were conducted in Santa Maria, RS, Brazil, in 2004/05 and 2005/06 cropping years, in a 6x6 triple lattice design. Treatments were composed of 32 common bean land varieties and four research-derived cultivars. Cultivar x environment interaction was detected for grain yield, seed coat color and cycle, what reveals a differential response of the land varieties to the different crop years. Land varieties were identified with high grain yield potential, commercially acceptable seed coat color from different commercial groups, early maturity and high dietary fiber content. '21

“m=1” coatings

DEFF Research Database (Denmark)

Cooper-Jensen, C.; Klinkby, Esben Bryndt; Beaucour, J.

For neutrons the critical angle of Ni is defined as m=1. If one needs a coating with reflectivity above m=1, people have traditionally used Ni58 or Ni-based multilayers. The reason to use Ni is the high neutron scattering density and the fact that it is easy to coat Ni using magnetron sputtering....... For a neutron guide the cost of shielding around the guide is a substantial part of the total cost of the guide. We are therefore looking at other materials than Ni for m=1 coatings. Both Be and diamond have the same or higher neutron scattering density than Ni, and have a much smaller absorption cross section....... Because of the lower absorption cross section, and because of fewer emitted gamma ray photons when a neutron is absorbed, these coatings are producing much less gamma radiation and therefore reduce the shielding costs. Be is frequently used in a wide range of science and technology applications. The only...

Cross-Talk between Staphylococcus aureus and Other Staphylococcal Species via the agr Quorum Sensing System

Directory of Open Access Journals (Sweden)

Jaime Canovas

2016-11-01

Full Text Available Staphylococci are associated with both humans and animals. While most are non-pathogenic colonizers, Staphylococcus aureus is an opportunistic pathogen capable of causing severe infections. S. aureus virulence is controlled by the agr quorum sensing system responding to secreted auto-inducing peptides (AIPs sensed by AgrC, a two component histidine kinase. agr loci are found also in other staphylococcal species and for Staphylococcus epidermidis, the encoded AIP represses expression of agr regulated virulence genes in S. aureus. In this study we aimed to better understand the interaction between staphylococci and S. aureus, and show that this interaction may eventually lead to the identification of new anti-virulence candidates to target S. aureus infections. Here we show that culture supernatants of 37 out of 52 staphylococcal isolates representing 17 different species inhibit S. aureus agr. The dog pathogen, Staphylococcus schleiferi, expressed the most potent inhibitory activity and was active against all four agr classes found in S. aureus. By employing a S. aureus strain encoding a constitutively active AIP receptor we show that the activity is mediated via agr. Subsequent cloning and heterologous expression of the S. schleiferi AIP in S. aureus demonstrated that this molecule was likely responsible for the inhibitory activity, and further proof was provided when pure synthetic S. schleiferi AIP was able to completely abolish agr induction of an S. aureus reporter strain. To assess impact on S. aureus virulence, we co-inoculated S. aureus and S. schleiferi in vivo in the Galleria mellonella wax moth larva, and found that expression of key S. aureus virulence factors was abrogated. Our data show that the S. aureus agr locus is highly responsive to other staphylococcal species suggesting that agr is an inter-species communication system. Based on these results we speculate that interactions between S. aureus and other colonizing staphylococci

La ingeniería agrícola en el mundo

Directory of Open Access Journals (Sweden)

José Eugenio Hernández H.

1989-07-01

Full Text Available Con el objeto de dar a conocer el grado de difusión que la ingeniería agrícola tiene en el mundo, en el presente artículo se indican la mayoría de los países y las universidades que en los distintos continentes ofrecen programas de pregrado y postgrado en ingeniería agrícola y áreas afines. Se trata de una recopilación de la información disponible en diferentes fuentes; pretendemos que sirva de punto de apoyo en la obtención de mayores datos para aquellas personas interesadas en iniciar la carrera a nivel de pregrado o bien en cursar estudios de postgrado en una de las áreas específicas de acción profesional de la ingeniería agrícola.

Ras-dva1 small GTPase regulates telencephalon development in Xenopus laevis embryos by controlling Fgf8 and Agr signaling at the anterior border of the neural plate

Directory of Open Access Journals (Sweden)

Maria B. Tereshina

2014-07-01

Full Text Available We previously found that the small GTPase Ras-dva1 is essential for the telencephalic development in Xenopus laevis because Ras-dva1 controls the Fgf8-mediated induction of FoxG1 expression, a key telencephalic regulator. In this report, we show, however, that Ras-dva1 and FoxG1 are expressed in different groups of cells; whereas Ras-dva1 is expressed in the outer layer of the anterior neural fold, FoxG1 and Fgf8 are activated in the inner layer from which the telencephalon is derived. We resolve this paradox by demonstrating that Ras-dva1 is involved in the transduction of Fgf8 signal received by cells in the outer layer, which in turn send a feedback signal that stimulates FoxG1 expression in the inner layer. We show that this feedback signal is transmitted by secreted Agr proteins, the expression of which is activated in the outer layer by mediation of Ras-dva1 and the homeodomain transcription factor Otx2. In turn, Agrs are essential for maintaining Fgf8 and FoxG1 expression in cells at the anterior neural plate border. Our finding reveals a novel feedback loop mechanism based on the exchange of Fgf8 and Agr signaling between neural and non-neural compartments at the anterior margin of the neural plate and demonstrates a key role of Ras-dva1 in this mechanism.

A abordagem ambiental na geografia agrária brasileira: uma análise dos periódicos Revista Agrária, Revista Campo-Território e Revista NERA

OpenAIRE

Artur Leonardo Andrade

2015-01-01

O presente estudo procurou analisar a abordagem ambiental na geografia agrária brasileira a partir dos periódicos Revista Agrária, Revista Campo-Território e Revista NERA. Para isso, foram selecionados e analisados 78 artigos que debatem, de forma direta, a questão ambiental. Como os periódicos foram criados a partir da década de 1990, a escolha metodológica possibilitou uma análise do período atual da geografia agrária, o pós-1990, marcado pela pluralidade teórico-metodológica. Esta pesquisa...

Política Agrícola Canadiense. Algunas lecciones para Argentina

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Rinaldo Antonio Colomé

2010-09-01

Full Text Available El objetivo general de este trabajo es analizar el diseño de la política agrícola canadiense, comparándola con las de los otros países altamente desarrollados y con la de Argentina.  Los objetivos específicos son: aAnalizar la política agrícola de Canadá referida a la producción y al comercio de granos y su efecto en los mercados internacionales; bAnalizar la política agrícola y comercial de Canadá referida al sector de oferta dirigida o regulada y sus efectos en el mercado doméstico y en los internacionales; c Realizar una comparación con Argentina. 

Heysham II/Torness AGR core integrity

International Nuclear Information System (INIS)

Birch, A.L.; Hampson, J.D.

1985-01-01

The design and construction process for the Heysham II/Torness AGR core structures is presented. The design intent utilizing all past experience in designing and building AGR core structures is described. The major aspects of the design criteria and the design conditions are outlined to demonstrate how the integrity of the Heysham II/Torness core is assured. Since no recognized codes of practice for graphite core design exist, the National Nuclear Corporation (NNC) have conceived design criteria utilizing reserve factors based on their design experience. Target reserve factors are defined for particular loading conditions including the ultimate 'safe-shutdown earthquake'. The substantial programme of computer analysis and RandD work to substantiate the design, including seismic qualification, is described. In keeping with their responsibility for the detailed core structure design and the fuel path geometry (guide tube system), NNC attach great importance to design/manufacture/construction liaison, which is demonstrated in the quality assurance section. (author)

MODELING AND ANALYSIS OF FISSION PRODUCT TRANSPORT IN THE AGR-3/4 EXPERIMENT

Energy Technology Data Exchange (ETDEWEB)

Humrickhouse, Paul W.; Collin, Blaise P.; Hawkes, Grant L.; Harp, Jason M.; Demkowicz, Paul A.; Petti, David A.

2016-11-01

In this work we describe the ongoing modeling and analysis efforts in support of the AGR-3/4 experiment. AGR-3/4 is intended to provide data to assess fission product retention and transport (e.g., diffusion coefficients) in fuel matrix and graphite materials. We describe a set of pre-test predictions that incorporate the results of detailed thermal and fission product release models into a coupled 1D radial diffusion model of the experiment, using diffusion coefficients reported in the literature for Ag, Cs, and Sr. We make some comparisons of the predicted Cs profiles to preliminary measured data for Cs and find these to be reasonable, in most cases within an order of magnitude. Our ultimate objective is to refine the diffusion coefficients using AGR-3/4 data, so we identify an analytical method for doing so and demonstrate its efficacy via a series of numerical experiments using the model predictions. Finally, we discuss development of a post-irradiation examination plan informed by the modeling effort and simulate some of the heating tests that are tentatively planned.

CD147 and AGR2 expression promote cellular proliferation and metastasis of head and neck squamous cell carcinoma

International Nuclear Information System (INIS)

Sweeny, Larissa; Liu, Zhiyong; Bush, Benjamin D.; Hartman, Yolanda; Zhou, Tong; Rosenthal, Eben L.

2012-01-01

The signaling pathways facilitating metastasis of head and neck squamous cell carcinoma (HNSCC) cells are not fully understood. CD147 is a transmembrane glycoprotein known to induce cell migration and invasion. AGR2 is a secreted peptide also known to promote cell metastasis. Here we describe their importance in the migration and invasion of HNSCC cells (FADU and OSC-19) in vitro and in vivo. In vitro, knockdown of CD147 or AGR2 decreased cellular proliferation, migration and invasion. In vivo, knockdown of CD147 or AGR2 expression decreased primary tumor growth as well as regional and distant metastasis. -- Highlights: ► We investigated AGR2 in head and neck squamous cell carcinoma for the first time. ► We explored the relationship between AGR2 and CD147 for the first time. ► AGR2 and CD147 appear to co-localize in head and squamous cell carcinoma samples. ► Knockdown of both AGR2 and CD147 reduced migration and invasion in vitro. ► Knockdown of both AGR2 and CD147 decreased metastasis in vivo.

Evaluation of a Low Temperature Cure Powder Coating

Science.gov (United States)

2008-05-01

4”x6”x1/4” Al 2024-T3 panels were chromate conversion coated by NDCEE per MIL-DTL-5514F Type 1 Class A  Reserved for LTCPC  27 – 4”x6”x1/4” Al...2024-T3 panels were chromate conversion coated by FRC Southeast per MIL-DTL- 5514F Type 1 Class A  Reserved for baseline coating JSEM - May...conducted under contract W74V8H- 04-D-0005 Task 427. DISCLAIMER: The contents of this document are not to be used for advertising , publication, or

Improvements in televisual and photographic inspections of AGRs

International Nuclear Information System (INIS)

Hayter, R.; Wadsworth, A.

1988-01-01

The visual inspection techniques and equipment used at AGR Power Stations have been improved and updated in the light of need and technological advance, new equipment being developed and introduced where necessary. Specifically this report covers the development and use of: a short TRIUMPH compatible photographic camera 600 mm long x 75 mm dia taking 50 shots on a 35 mm film; a 240 mm dia photographic pod taking high quality 70 mm format photographs of large in-reactor volumes; a photographic camera of cross section 37 x 17 mm for the inspection of helically wound AGR boilers and the subsequent development of this latter device into a state of the art TV inspection camera. (author)

The Agr communication system provides a benefit to the populations of Listeria monocytogenes in soil.

Science.gov (United States)

Vivant, Anne-Laure; Garmyn, Dominique; Gal, Laurent; Piveteau, Pascal

2014-01-01

In this study, we investigated whether the Agr communication system of the pathogenic bacterium Listeria monocytogenes was involved in adaptation and competitiveness in soil. Alteration of the ability to communicate, either by deletion of the gene coding the response regulator AgrA (response-negative mutant) or the signal pro-peptide AgrD (signal-negative mutant), did not affect population dynamics in soil that had been sterilized but survival was altered in biotic soil suggesting that the Agr system of L. monocytogenes was involved to face the complex soil biotic environment. This was confirmed by a set of co-incubation experiments. The fitness of the response-negative mutant was lower either in the presence or absence of the parental strain but the fitness of the signal-negative mutant depended on the strain with which it was co-incubated. The survival of the signal-negative mutant was higher when co-cultured with the parental strain than when co-cultured with the response-negative mutant. These results showed that the ability to respond to Agr communication provided a benefit to listerial cells to compete. These results might also indicate that in soil, the Agr system controls private goods rather than public goods.

Geografia agrícola brasileira: gênese e diversidad

OpenAIRE

Suzuki, Julio César

2009-01-01

A geografia agrícola é muito recente. A sua definição como um fragmento de conhecimento não possui mais de meio século. No entanto, o conhecimento sobre o campo é quase tão antigo quanto a história do homem, pelo menos aquela referente ao homem, cuja prática da agricultura alterou as possibilidades de desenvolvimento social. Desta forma, entendemos a geografia agrária como um momento particular de estruturação de conhecimentos sobre o campo e a agricultura, com base na sistematização do conhe...

CD147 and AGR2 expression promote cellular proliferation and metastasis of head and neck squamous cell carcinoma

Energy Technology Data Exchange (ETDEWEB)

Sweeny, Larissa, E-mail: larissasweeny@gmail.com [Department of Surgery, University of Alabama, Division of Otolaryngology-Head and Neck Surgery, 1670 University Boulevard, Volker Hall G082, Birmingham, Alabama (United States); Liu, Zhiyong; Bush, Benjamin D.; Hartman, Yolanda [Department of Surgery, University of Alabama, Division of Otolaryngology-Head and Neck Surgery, 1670 University Boulevard, Volker Hall G082, Birmingham, Alabama (United States); Zhou, Tong [Department of Medicine, Division of Immunology and Rheumatology, 1825 University Boulevard, Shelby Biomedical Research Building 302, Birmingham, Alabama (United States); Rosenthal, Eben L., E-mail: oto@uab.edu [Department of Surgery, University of Alabama, Division of Otolaryngology-Head and Neck Surgery, 1670 University Boulevard, Volker Hall G082, Birmingham, Alabama (United States)

2012-08-15

The signaling pathways facilitating metastasis of head and neck squamous cell carcinoma (HNSCC) cells are not fully understood. CD147 is a transmembrane glycoprotein known to induce cell migration and invasion. AGR2 is a secreted peptide also known to promote cell metastasis. Here we describe their importance in the migration and invasion of HNSCC cells (FADU and OSC-19) in vitro and in vivo. In vitro, knockdown of CD147 or AGR2 decreased cellular proliferation, migration and invasion. In vivo, knockdown of CD147 or AGR2 expression decreased primary tumor growth as well as regional and distant metastasis. -- Highlights: Black-Right-Pointing-Pointer We investigated AGR2 in head and neck squamous cell carcinoma for the first time. Black-Right-Pointing-Pointer We explored the relationship between AGR2 and CD147 for the first time. Black-Right-Pointing-Pointer AGR2 and CD147 appear to co-localize in head and squamous cell carcinoma samples. Black-Right-Pointing-Pointer Knockdown of both AGR2 and CD147 reduced migration and invasion in vitro. Black-Right-Pointing-Pointer Knockdown of both AGR2 and CD147 decreased metastasis in vivo.

The 2009 Lindau Nobel Laureate Meeting: Peter Agre, Chemistry 2003.

Science.gov (United States)

Agre, Peter

2009-12-09

Peter Agre, born in 1949 in Northfield Minnesota, shared the 2003 Nobel Prize in Chemistry with Roderick MacKinnon for his discovery of aquaporins, the channel proteins that allow water to cross the cell membrane. Agre's interest medicine was inspired by the humanitarian efforts of the Medical Missionary program run by the Norwegians of his home community in Minnesota. Hoping to provide new treatments for diseases affecting the poor, he joined a cholera laboratory during medical school at Johns Hopkins. He found that he enjoyed biomedical research, and continued his laboratory studies for an additional year after medical school. Agre completed his clinical training at Case Western Hospitals of Cleveland and the University of North Carolina, and returned to Johns Hopkins in 1981. There, his serendipitous discovery of aquaporins was made while pursuing the identity of the Rhesus (Rh) antigen. For a century, physiologists and biophysicists had been trying to understand the mechanism by which fluid passed across the cell's plasma membrane. Biophysical evidence indicated a limit to passive diffusion of water, suggesting the existence of another mechanism for water transport across the membrane. The putative "water channel," however, could not be identified. In 1988, while attempting to purify the 30 kDa Rh protein, Agre and colleagues began investigating a 28 kDa contaminant that they believed to be a proteolytic fragment of the Rh protein. Subsequent studies over the next 3-4 years revealed that the contaminant was a membrane-spanning oligomeric protein, unrelated to the Rh antigen, and that it was highly abundant in renal tubules and red blood cells. Still, they could not assign a function to it. The breakthrough came following a visit with his friend and former mentor John Parker. After Agre described the properties of the mysterious 28 kDa protein, Parker suggested that it might be the long-sought-after water channel. Agre and colleagues tested this idea by

Improving thermal model prediction through statistical analysis of irradiation and post-irradiation data from AGR experiments

International Nuclear Information System (INIS)

Pham, Binh T.; Hawkes, Grant L.; Einerson, Jeffrey J.

2014-01-01

As part of the High Temperature Reactors (HTR) R and D program, a series of irradiation tests, designated as Advanced Gas-cooled Reactor (AGR), have been defined to support development and qualification of fuel design, fabrication process, and fuel performance under normal operation and accident conditions. The AGR tests employ fuel compacts placed in a graphite cylinder shrouded by a steel capsule and instrumented with thermocouples (TC) embedded in graphite blocks enabling temperature control. While not possible to obtain by direct measurements in the tests, crucial fuel conditions (e.g., temperature, neutron fast fluence, and burnup) are calculated using core physics and thermal modeling codes. This paper is focused on AGR test fuel temperature predicted by the ABAQUS code's finite element-based thermal models. The work follows up on a previous study, in which several statistical analysis methods were adapted, implemented in the NGNP Data Management and Analysis System (NDMAS), and applied for qualification of AGR-1 thermocouple data. Abnormal trends in measured data revealed by the statistical analysis are traced to either measuring instrument deterioration or physical mechanisms in capsules that may have shifted the system thermal response. The main thrust of this work is to exploit the variety of data obtained in irradiation and post-irradiation examination (PIE) for assessment of modeling assumptions. As an example, the uneven reduction of the control gas gap in Capsule 5 found in the capsule metrology measurements in PIE helps identify mechanisms other than TC drift causing the decrease in TC readings. This suggests a more physics-based modification of the thermal model that leads to a better fit with experimental data, thus reducing model uncertainty and increasing confidence in the calculated fuel temperatures of the AGR-1 test

Improving thermal model prediction through statistical analysis of irradiation and post-irradiation data from AGR experiments

Energy Technology Data Exchange (ETDEWEB)

Pham, Binh T., E-mail: Binh.Pham@inl.gov [Human Factor, Controls and Statistics Department, Nuclear Science and Technology, Idaho National Laboratory, Idaho Falls, ID 83415 (United States); Hawkes, Grant L. [Thermal Science and Safety Analysis Department, Nuclear Science and Technology, Idaho National Laboratory, Idaho Falls, ID 83415 (United States); Einerson, Jeffrey J. [Human Factor, Controls and Statistics Department, Nuclear Science and Technology, Idaho National Laboratory, Idaho Falls, ID 83415 (United States)

2014-05-01

As part of the High Temperature Reactors (HTR) R and D program, a series of irradiation tests, designated as Advanced Gas-cooled Reactor (AGR), have been defined to support development and qualification of fuel design, fabrication process, and fuel performance under normal operation and accident conditions. The AGR tests employ fuel compacts placed in a graphite cylinder shrouded by a steel capsule and instrumented with thermocouples (TC) embedded in graphite blocks enabling temperature control. While not possible to obtain by direct measurements in the tests, crucial fuel conditions (e.g., temperature, neutron fast fluence, and burnup) are calculated using core physics and thermal modeling codes. This paper is focused on AGR test fuel temperature predicted by the ABAQUS code's finite element-based thermal models. The work follows up on a previous study, in which several statistical analysis methods were adapted, implemented in the NGNP Data Management and Analysis System (NDMAS), and applied for qualification of AGR-1 thermocouple data. Abnormal trends in measured data revealed by the statistical analysis are traced to either measuring instrument deterioration or physical mechanisms in capsules that may have shifted the system thermal response. The main thrust of this work is to exploit the variety of data obtained in irradiation and post-irradiation examination (PIE) for assessment of modeling assumptions. As an example, the uneven reduction of the control gas gap in Capsule 5 found in the capsule metrology measurements in PIE helps identify mechanisms other than TC drift causing the decrease in TC readings. This suggests a more physics-based modification of the thermal model that leads to a better fit with experimental data, thus reducing model uncertainty and increasing confidence in the calculated fuel temperatures of the AGR-1 test.

La normalización y certificación de tractores agrícolas en México

OpenAIRE

Alma Velia Ayala Garay; Rocío Cervantes Osornio; Marco Antonio Audelo Benítez; Noé Velázquez López; José Manuel Vargas Sállago

2013-01-01

El tractor agrícola es la principal fuente de potencia dentro de una unidad de producción. Por lo tanto para los usuarios de maquinaria agrícola, resulta una prioridad contar con mecanismos que permitan dar seguridad al usuario final o productor agrícola en el funcionamiento y calidad de los tractores, para esto el objetivo del presente es dar a conocer la evolución de la normalización y certificación de la maquinaria agrícola en México, sus impactos y tendencias, por medio de una descripción...

AGR core models and their application to HTRs and RBMKs

International Nuclear Information System (INIS)

Baylis, Samuel

2014-01-01

EDF Energy operates 14 AGRs, commissioned between 1976 and 1989. The graphite moderators of these gas cooled reactors are subjected to a number of ageing processes under fast neutron irradiation in a high temperature CO2 environment. As the graphite ages, continued safe operation requires an advanced whole-core modeling capability to enable accurate assessments of the core’s ability to fulfil fundamental nuclear safety requirements. This is also essential in evaluating the reactor's remaining economic lifetime, and similar assessments are useful for HTRs in the design stage. A number of computational and physical models of AGR graphite cores have been developed or are in development, allowing simulation of the reactors in normal, fault and seismic conditions. Many of the techniques developed are applicable to other graphite moderated reactors. Modeling of the RBMK allows validation against a core in a more advanced state of ageing than the AGRs, while there is also an opportunity to adapt the models for high temperature reactors. As an example, a finite element model of the HTR-PM side reflector based on rigid bodies and nonlinear springs is developed, allowing rapid assessments of distortion in the structure to be made. A model of the RBMK moderator has also been produced using an established AGR code based on similar methods. In addition, this paper discusses the limitations of these techniques and the development of more complex core models that address these limitations, along with the lessons that can be applied to HTRs. (author)

La maquinaria agrícola en el siglo XX

OpenAIRE

Ruiz-Altisent, Margarita; Gil Sierra, Jacinto

2000-01-01

La evolución de la maquinaria agrícola en el siglo XX ha sido tan espectacular que, de los tres grandes avances habidos a lo largo de la historia de la maquinaria agrícola, dos de ellos podemos considerar que marcan el comienzo y el fin del siglo XX. El primer avance fundamental se dio el día en que el hombre que removía la tierra golpeándola con una herramienta tipo azada decidió avanzar con ella introducida en el suelo venciendo la fuerza de tiro. Nació así el arado en un tiempo indetermina...

Hanford Site technical baseline database. Revision 1

International Nuclear Information System (INIS)

Porter, P.E.

1995-01-01

This report lists the Hanford specific files (Table 1) that make up the Hanford Site Technical Baseline Database. Table 2 includes the delta files that delineate the differences between this revision and revision 0 of the Hanford Site Technical Baseline Database. This information is being managed and maintained on the Hanford RDD-100 System, which uses the capabilities of RDD-100, a systems engineering software system of Ascent Logic Corporation (ALC). This revision of the Hanford Site Technical Baseline Database uses RDD-100 version 3.0.2.2 (see Table 3). Directories reflect those controlled by the Hanford RDD-100 System Administrator. Table 4 provides information regarding the platform. A cassette tape containing the Hanford Site Technical Baseline Database is available

Mod increases AGR boiler output

International Nuclear Information System (INIS)

Jones, W.K.C.; Rider, G.; Taylor, D.E.

1986-01-01

During the commissioning runs of the first reactor units at Heysham I and Hartlepool Advanced Gas-cooled Reactors (AGRs), non-uniform temperature distributions were observed across individual boiler units which were more severe than those predicted from the design analysis. This article describes the re-orificing (referruling) of the boilers to overcome this problem. The referruling has reduced boiler sensitivity and resulted in an increase of load of 7 or 8%. (U.K.)

"m=1" coatings for neutron guides

DEFF Research Database (Denmark)

Cooper-Jensen, C.P.; Vorobiev, A.; Klinkby, Esben Bryndt

2014-01-01

A substantial part of the price for a neutron guide is the shielding needed because of the gamma ray produced when neutrons are absorbed. This absorption occurs in the coating and the substrate of the neutron guides. Traditional m=1 coatings have been made of Ni and if reflectivity over...... the critical angle of Ni is needed one has used Ni58 or Ni/Ti multilayer coatings. Ni has one of the highest neutron scattering density but it also has a fairly high absorption cross section for cold and thermal neutrons and when a neutron is absorbed it emits a lot of gamma rays, some with energies above 9 Me...... of diamond coatings to show the potential for using these coatings in neutron guides....

Antisense locked nucleic acids targeting agrA inhibit quorum sensing and pathogenesis of community-associated methicillin-resistant Staphylococcus aureus.

Science.gov (United States)

Da, F; Yao, L; Su, Z; Hou, Z; Li, Z; Xue, X; Meng, J; Luo, X

2017-01-01

Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) is commonly associated with nonnosocomial skin and soft tissue infections due to its virulence, which is mainly controlled by the accessory gene regulator (agr) quorum sensing (QS) system. In this study (KFF) 3 K peptide-conjugated locked nucleic acids (PLNAs) targeting agrA mRNA were developed to inhibit agr activity and arrest the pathogenicity of CA-MRSA. Two PLNAs were designed, and synthesized, after predicting the secondary structure of agrA mRNA. The influence on bacterial growth was tested using a growth curve assay. RT-qPCR, haemolysis assay, lactate dehydrogenase release assay and chemotaxis assay were used to evaluate the effects of the PLNAs on inhibiting agr QS. A mouse skin infection model was employed to test the protective effect of the PLNAs in vivo. None of the PLNAs were found to be bacteriostatic or bactericidal in vitro. However, one PLNA, PLNA34, showed strong ability to suppress expression of agrA and the effector molecule RNAIII in USA300 LAC strain. Furthermore, PLNA34 inhibited the expression of virulence genes that are upregulated by agr, including hla, psmα, psmβ and pvl. The haemolytic activity of the supernatants from PLNA34-treated bacteria was also dramatically reduced, as well as the capacity to lyse and recruit neutrophils. Moreover, PLNA34 showed high levels of protection in the CA-MRSA mouse skin infection model. The anti-agrA PLNA34 can effectively inhibit the agr QS and suppress CA-MRSA pathogenicity. agrA is a promising target for the development of antisense oligonucleotides to block agr QS. Journal of Applied Microbiology © 2016 The Society for Applied Microbiology.

Chitinase expression in Listeria monocytogenes is positively regulated by the Agr system

DEFF Research Database (Denmark)

Paspaliari, Dafni Katerina; Mollerup, Maria Storm; Kallipolitis, Birgitte H.

2014-01-01

The food-borne pathogen Listeria monocytogenes encodes two chitinases, ChiA and ChiB, which allow the bacterium to hydrolyze chitin, the second most abundant polysaccharide in nature. Intriguingly, despite the absence of chitin in human and mammalian hosts, both of the chitinases have been deemed...... important for infection, through a mechanism that, at least in the case of ChiA, involves modulation of host immune responses. In this study, we show that the expression of the two chitinases is subject to regulation by the listerial agr system, a homologue of the agr quorum-sensing system of Staphylococcus...... chitinolytic activity on agar plates. Agr was specifically induced in response to chitin addition in stationary phase and agrD was found to regulate the amount of chiA, but not chiB, transcripts. Although the transcript levels of chiB did not depend on agrD, the extracellular protein levels of both chitinases...

Design and development of steam generators for the AGR power stations at Heysham II/Torness

Energy Technology Data Exchange (ETDEWEB)

Charcharos, A N; Jones, A G [National Nuclear Corp. Ltd., Cheshire (United Kingdom)

1984-07-01

The current AGR steam generator design is a development of the successful once-through units supplied for the Oldbury Magnox and Hinkley/Hunterston AGR power stations. These units have demonstrated proven control and reliability in service. In this paper the factors which have dictated the design and layout of the latest AGR steam generators are described and reference made to the latest high temperature design techniques that have been employed. Details of development work to support the design and establish the performance characteristics over the range of plant operating conditions are also given. To comply with current UK safety standards, the AGR steam generators and associated plant are designed to accommodate seismic loadings. In addition, provision is made for an independent heat removal system for post reactor trip operations. (author)

Design and development of steam generators for the AGR power stations at Heysham II/Torness

International Nuclear Information System (INIS)

Charcharos, A.N.; Jones, A.G.

1984-01-01

The current AGR steam generator design is a development of the successful once-through units supplied for the Oldbury Magnox and Hinkley/Hunterston AGR power stations. These units have demonstrated proven control and reliability in service. In this paper the factors which have dictated the design and layout of the latest AGR steam generators are described and reference made to the latest high temperature design techniques that have been employed. Details of development work to support the design and establish the performance characteristics over the range of plant operating conditions are also given. To comply with current UK safety standards, the AGR steam generators and associated plant are designed to accommodate seismic loadings. In addition, provision is made for an independent heat removal system for post reactor trip operations. (author)

On the use of flux-adjoint condensed nuclear data for 1-group AGR kinetics

International Nuclear Information System (INIS)

Hutt, P.K.

1979-03-01

Following previous work on the differences between one and two neutron group AGR kinetics the possible advantages of flux-adjoint condensed lattice data over the simple flux condensation procedure are investigated. Analytic arguments are given for expecting flux-adjoint condensation to give a better representation of rod worth slopes and flux shape changes associated with partially rodded cores. These areas have previously been found to yield most of the one to two neutron group differences. The validity of these arguments is demonstrated comparing various calculations. (U.K.)

The ATP-Dependent Protease ClpP Inhibits Biofilm Formation by Regulating Agr and Cell Wall Hydrolase Sle1 in Staphylococcus aureus

Science.gov (United States)

Liu, Qian; Wang, Xing; Qin, Juanxiu; Cheng, Sen; Yeo, Won-Sik; He, Lei; Ma, Xiaowei; Liu, Xiaoyun; Li, Min; Bae, Taeok

2017-01-01

Biofilm causes hospital-associated infections on indwelling medical devices. In Staphylococcus aureus, Biofilm formation is controlled by intricately coordinated network of regulating systems, of which the ATP-dependent protease ClpP shows an inhibitory effect. Here, we demonstrate that the inhibitory effect of ClpP on biofilm formation is through Agr and the cell wall hydrolase Sle1. Biofilm formed by clpP mutant consists of proteins and extracellular DNA (eDNA). The increase of the protein was, at least in part, due to the reduced protease activity of the mutant, which was caused by the decreased activity of agr. On the other hand, the increase of eDNA was due to increased cell lysis caused by the higher level of Sle1. Indeed, as compared with wild type, the clpP mutant excreted an increased level of eDNA, and showed higher sensitivity to Triton-induced autolysis. The deletion of sle1 in the clpP mutant decreased the biofilm formation, the level of eDNA, and the Triton-induced autolysis to wild-type levels. Despite the increased biofilm formation capability, however, the clpP mutant showed significantly reduced virulence in a murine model of subcutaneous foreign body infection, indicating that the increased biofilm formation capability cannot compensate for the intrinsic functions of ClpP during infection. PMID:28555174

The ATP-Dependent Protease ClpP Inhibits Biofilm Formation by Regulating Agr and Cell Wall Hydrolase Sle1 in Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Qian Liu

2017-05-01

Full Text Available Biofilm causes hospital-associated infections on indwelling medical devices. In Staphylococcus aureus, Biofilm formation is controlled by intricately coordinated network of regulating systems, of which the ATP-dependent protease ClpP shows an inhibitory effect. Here, we demonstrate that the inhibitory effect of ClpP on biofilm formation is through Agr and the cell wall hydrolase Sle1. Biofilm formed by clpP mutant consists of proteins and extracellular DNA (eDNA. The increase of the protein was, at least in part, due to the reduced protease activity of the mutant, which was caused by the decreased activity of agr. On the other hand, the increase of eDNA was due to increased cell lysis caused by the higher level of Sle1. Indeed, as compared with wild type, the clpP mutant excreted an increased level of eDNA, and showed higher sensitivity to Triton-induced autolysis. The deletion of sle1 in the clpP mutant decreased the biofilm formation, the level of eDNA, and the Triton-induced autolysis to wild-type levels. Despite the increased biofilm formation capability, however, the clpP mutant showed significantly reduced virulence in a murine model of subcutaneous foreign body infection, indicating that the increased biofilm formation capability cannot compensate for the intrinsic functions of ClpP during infection.

Cross-Talk between Staphylococcus aureus and Other Staphylococcal Species via the agr Quorum Sensing System

DEFF Research Database (Denmark)

Canovas de la Nuez, Jaime; Baldry, Mara; Bojer, Martin S

2016-01-01

-inducing peptides (AIPs) sensed by AgrC, a two component histidine kinase. agr loci are found also in other staphylococcal species and for Staphylococcus epidermidis, the encoded AIP represses expression of agr regulated virulence genes in S. aureus. In this study we aimed to better understand the interaction...... between staphylococci and S. aureus, and show that this interaction may eventually lead to the identification of new anti-virulence candidates to target S. aureus infections. Here we show that culture supernatants of 37 out of 52 staphylococcal isolates representing 17 different species inhibit S. aureus...... suggesting that agr is an inter-species communication system. Based on these results we speculate that interactions between S. aureus and other colonizing staphylococci will significantly influence the ability of S. aureus to cause infection, and we propose that other staphylococci are potential sources...

How safe is an AGR

International Nuclear Information System (INIS)

Wilkinson, Max

1987-01-01

The paper concerns the safety of an AGR, in the light of the Chernobyl and Three Mile Island reactor accidents. To assess the safety systems the resources editor of the Financial Times newspaper spent an afternoon trying to do as much damage as possible to one of the Hinkley Point B advanced gas cooled reactors - on the simulator at the Central Electricity Generating Board's training centre at Oldbury. An account of the experience in the nuclear power control room is given. (U.K.)

An agr-like two-component regulatory system in Lactobacillus plantarum is involved in production of a novel cyclic peptide and regulation of adherence

NARCIS (Netherlands)

Sturme, M.H.J.; Nakayama, J.; Molenaar, D.; Murakami, Y.; Kunugi, R.; Fujii, T.; Vaughan, E.E.; Kleerebezem, M.; Vos, de W.M.

2005-01-01

We have analyzed a locus on the annotated Lactobacillus plantarum WCFS1 genome that showed homology to the staphylococcal agr quorum-sensing system and designated it lam for Lactobacillus agr-like module. Production of the lamBDCA transcript was shown to be growth phase dependent. Analysis of a

Listeria monocytogenes differential transcriptome analysis reveals temperature-dependent Agr regulation and suggests overlaps with other regulons.

Science.gov (United States)

Garmyn, Dominique; Augagneur, Yoann; Gal, Laurent; Vivant, Anne-Laure; Piveteau, Pascal

2012-01-01

Listeria monocytogenes is a ubiquitous, opportunistic pathogenic organism. Environmental adaptation requires constant regulation of gene expression. Among transcriptional regulators, AgrA is part of an auto-induction system. Temperature is an environmental cue critical for in vivo adaptation. In order to investigate how temperature may affect AgrA-dependent transcription, we compared the transcriptomes of the parental strain L. monocytogenes EGD-e and its ΔagrA mutant at the saprophytic temperature of 25°C and in vivo temperature of 37°C. Variations of transcriptome were higher at 37°C than at 25°C. Results suggested that AgrA may be involved in the regulation of nitrogen transport, amino acids, purine and pyrimidine biosynthetic pathways and phage-related functions. Deregulations resulted in a growth advantage at 37°C, but affected salt tolerance. Finally, our results suggest overlaps with PrfA, σB, σH and CodY regulons. These overlaps may suggest that through AgrA, Listeria monocytogenes integrates information on its biotic environment.

Effect of protective coating on microhardness of a new glass ionomer cement: Nanofilled coating versus unfilled resin.

Science.gov (United States)

Faraji, Foad; Heshmat, Haleh; Banava, Sepideh

2017-01-01

EQUIA TM is a new gastrointestinal (GI) system with high compressive strength, surface microhardness (MH), and fluoride release potential. This in vitro study aimed to assess the effect of aging and type of protective coating on the MH of EQUIA TM GI cement. A total of 30 disc-shaped specimens measuring 9 mm in diameter and 2 mm in thickness were fabricated of EQUIA TM GI and divided into three groups of G-Coat nanofilled coating (a), no coating (b) and margin bond (c). The Vickers MH value of specimens was measured before (baseline) and at 3 and 6 months after water storage. Data were analyzed using repeated measures ANOVA. Group B had significantly higher MH than the other two groups at baseline. Both G-Coat and margin bond increased the surface MH of GI at 3 and 6 months. The MH values of G-Coat and margin bond groups did not significantly increase or decrease between 3 and 6 months. The increase in MH was greater in the G-Coat compared to the margin bond group in the long-term. Clinically, margin bond may be a suitable alternative when G-Coat is not available.

Economía de Producción Agrícola en Colombia: Capitulo 1. Regiones Geográficas y Agrícolas de Colombia

Directory of Open Access Journals (Sweden)

Beltrán G. Gregorio

1953-09-01

Full Text Available Es Colombia la única nación en la América del Sur que tiene costas en ambos océanos lo cual le da una gran ventaja tanto para el comercio mundial como para el inter-americano. Así se puede comunicar por mar sin necesidad de cruzar el canal de Panamá o el Cabo de Hornos con todos los países latinoamericanos, con ambas costas de los Estados Unidos y Canadá y con Europa o el Oriente. Las fronteras terrestres limitan con Venezuela, Brasil, Perú, Ecuador y Panamá. En los límites con dos países vecinos, Venezuela y Ecuador, tiene fuertes núcleos de población. Según Wihitbeck y Williams el país está dividido en cuatro grandes regiones naturales, 1 EL Corazón Montañoso que está formado por tres ramas de la Cordillera de los Andes y la Parte alta de los valles de los ríos Magdalena y Cauca; 2 La Costa del Caribe abarca todas las tierras bajas de la parte norte de Colombia excepto la zona del río Atrato; incluye los departamentos del Magdalena, Atlántico, Bolívar y Córdoba, la Comisaría de la Guajira y además la parte baja de los valles de los ríos Magdalena y Cauca. En la Costa Caribe se incluye por su localización, la Sierra Nevada de Santa Marta, aún cuando ésta por sus características fitogeográficas es más similar al Corazón Montañoso; 3 La Costa del Pacífico y Valle del Atrato es la región formada por las vertientes occidentales de la Cordillera Oriental y su prolongación La Serranía de Abibe. Incluye los valles de los ríos Atrato y San Juan y la Serranía del Baudó. Esta zona está clasificada fitogeográficamente como bosque ecuatorial o de zonas lluviosas; 4 Las Tierras Bajas Tropicales del Este son el area mas grande del país: abarcan aproximadamente las dos terceras partes del territorio nacional aún cuando en ellas sólo vive cerca de un 2 por ciento de la población. Es una zona plana al Norte, tiene en su parte media elevaciones escalonadas hacia el Amazonas que no pasan de 800 metros de altura

Developing equipment for AGR remote visual inspection

International Nuclear Information System (INIS)

James, P.W.; Walton, P.J.

1985-01-01

The Remote Inspection Group is part of the CEGB's Generation Development and Construction Division, and has responsibility for the design, development, procurement, testing and setting to work of the equipment provided to carry out routine remote visual inspections of its AGRs. This equipment includes both the viewing devices and the necessary placement equipment. (author)

Building on the AGR experience

International Nuclear Information System (INIS)

Churchill, G.F.

1985-01-01

Experience with AGR reactors has indicated that quality assurance applied to procurement of plant and services throughout the hierarchy of purchasers and suppliers is a main area where there is scope for improvement. In view of this, improvements for procurement have been undertaken. These include a) the rationalisation of specified requirements for quality assurance systems, with the particular needs of each contract, and b) the rationalisation of purchasers' involvement in suppliers' quality assurance activities. Both aspects of procurement are described and discussed. (U.K.)

Effects of tongue cleaning on bacterial flora in tongue coating and dental plaque: a crossover study.

Science.gov (United States)

Matsui, Miki; Chosa, Naoyuki; Shimoyama, Yu; Minami, Kentaro; Kimura, Shigenobu; Kishi, Mitsuo

2014-01-14

The effects of tongue cleaning on reconstruction of bacterial flora in dental plaque and tongue coating itself are obscure. We assessed changes in the amounts of total bacteria as well as Fusobacterium nucleatum in tongue coating and dental plaque specimens obtained with and without tongue cleaning. We conducted a randomized examiner-blind crossover study using 30 volunteers (average 23.7 ± 3.2 years old) without periodontitis. After dividing randomly into 2 groups, 1 group was instructed to clean the tongue, while the other did not. On days 1 (baseline), 3, and 10, tongue coating and dental plaque samples were collected after recording tongue coating score (Winkel tongue coating index: WTCI). After a washout period of 3 weeks, the same examinations were performed with the subjects allocated to the alternate group. Genomic DNA was purified from the samples and applied to SYBR® Green-based real-time PCR to quantify the amounts of total bacteria and F. nucleatum. After 3 days, the WTCI score recovered to baseline, though the amount of total bacteria in tongue coating was significantly lower as compared to the baseline. In plaque samples, the bacterial amounts on day 3 and 10 were significantly lower than the baseline with and without tongue cleaning. Principal component analysis showed that variations of bacterial amounts in the tongue coating and dental plaque samples were independent from each other. Furthermore, we found a strong association between amounts of total bacteria and F. nucleatum in specimens both. Tongue cleaning reduced the amount of bacteria in tongue coating. However, the cleaning had no obvious contribution to inhibit dental plaque formation. Furthermore, recovery of the total bacterial amount induced an increase in F. nucleatum in both tongue coating and dental plaque. Thus, it is recommended that tongue cleaning and tooth brushing should both be performed for promoting oral health.

Initial Gamma Spectrometry Examination of the AGR-3/4 Irradiation

Energy Technology Data Exchange (ETDEWEB)

Harp, Jason M.; Demkowicz, Paul A.; Stempien, John D.

2016-11-01

The initial results from gamma spectrometry examination of the different components from the combined third and fourth US Advanced Gas Reactor Fuel Development TRISO-coated particle fuel irradiation tests (AGR-3/4) have been analyzed. This experiment was designed to provide information about in-pile fission product migration. In each of the 12 capsules, a single stack of four compacts with designed-to-fail particles surrounded by two graphitic diffusion rings (inner and outer) and a graphite sink were irradiated in the Idaho National Laboratory’s Advanced Test Reactor. Gamma spectrometry has been used to evaluate the gamma-emitting fission product inventory of compacts from the irradiation and evaluate the burnup of these compacts based on the activity of the radioactive cesium isotopes (Cs-134 and Cs-137) in the compacts. Burnup from gamma spectrometry compares well with predicted burnup from simulations. Additionally, inner and outer rings were also examined by gamma spectrometry both to evaluate the fission product inventory and the distribution of gamma-emitting fission products within the rings using gamma emission computed tomography. The cesium inventory of the scanned rings compares acceptably well with the expected inventory from fission product transport modeling. The inventory of the graphite fission product sinks is also being evaluated by gamma spectrometry.

Comércio agrícola: o Brasil e a OMC

Directory of Open Access Journals (Sweden)

Danielle Annoni

2004-03-01

Full Text Available The agricultural and textile sectors, have been the greaters targets of the developed countries protectionism, that possess in common the fact that the amount of man-power used is sufficiently great, it means variation of the products final cost. Therefore, it is not difficult to understand why the most underdeveloped countries are more competitive in the dispute of the world-wide market’s control in these sectors. Thus the importance of the OMC elapses, in the search for the effectiveness of international trade regulation of agricultural goods is an activity that interests the developing countries, what is particularly applicable to Brazil, where the agricultural products answers almost for one third of the exportations.Los sectores agrícolas y textil, han sido los mayores objetivos del proteccionismo de los países desarrollados, que poseen en común la cantidad de mano-de-obra usado y esta energía es suficientemente grande y significa variación del costo final del producto. Por tanto, no es difícil comprender porque cuanto más subdesarrollados los países, más serán competitivos y amenazadores para el conflicto sobre el control del mercado mundial en estos sectores. Así la importancia del OMC transcurre, en la búsqueda para la eficacia de la regulación del comercio internacional de mercancías agrícolas es una, actividad que interesa a los países en vías de desarrollo en su totalidad, lo que es particularmente aplicable al Brasil, donde los productos agrícolas casi contestan para un tercio de las exportaciones.Os setores agrícola e têxtil, têm sido os maiores alvos do protecionismo dos países desenvolvidos, que possuem em comum o fato de que a quantidade de mão-de-obra utilizada é bastante grande o que significa margem de variação do custo final do produto. Portanto, não é difícil entender porque os países quão mais subdesenvolvidos forem mais competitivos e ameaçadores são na disputa pelo controle do mercado

Information architecture. Volume 2, Part 1: Baseline analysis summary

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-12-01

The Department of Energy (DOE) Information Architecture, Volume 2, Baseline Analysis, is a collaborative and logical next-step effort in the processes required to produce a Departmentwide information architecture. The baseline analysis serves a diverse audience of program management and technical personnel and provides an organized way to examine the Department`s existing or de facto information architecture. A companion document to Volume 1, The Foundations, it furnishes the rationale for establishing a Departmentwide information architecture. This volume, consisting of the Baseline Analysis Summary (part 1), Baseline Analysis (part 2), and Reference Data (part 3), is of interest to readers who wish to understand how the Department`s current information architecture technologies are employed. The analysis identifies how and where current technologies support business areas, programs, sites, and corporate systems.

O Brasil agrícola: o tortuoso e difícil “caminho da roça”

Directory of Open Access Journals (Sweden)

João Klug

2016-01-01

Full Text Available Brasil atualmente é um dos maiores produtores de commodities agrícolas, tais como soja, café, carne (bovina, suína e de aves, açúcar e suco de laranja, e o país se orgulha disso. Essa é uma realidade que começou com a adoção da Revolução Verde na década de 1960 (alta tecnologia no campo, mecanização, insumos, seleção genética, etc., quando foi implantado um modelo de farmerização. Para se chegar a esse modelo de agricultura, concentrador e pouco democrático, o Brasil precisou de quase cinco séculos. Durante a maior parte desse longo período, a agricultura não era vista como atividade nobre, ao contrário, procurava-se superar a identidade agrária, visto que a atividade não conferia status. Em certa medida, o Brasil teve vergonha de ser agrícola. Neste trabalho, o objetivo é analisar como o Brasil, um país agrário, durante mais de três séculos teve dificuldades de assumir uma identidade agrária, especialmente em função da influência de uma mentalidade portuguesa não afeita às lides agrícolas.

Should Studies of Diabetes Treatment Stratification Correct for Baseline HbA1c?

Science.gov (United States)

Jones, Angus G.; Lonergan, Mike; Henley, William E.; Pearson, Ewan R.; Hattersley, Andrew T.; Shields, Beverley M.

2016-01-01

Aims Baseline HbA1c is a major predictor of response to glucose lowering therapy and therefore a potential confounder in studies aiming to identify other predictors. However, baseline adjustment may introduce error if the association between baseline HbA1c and response is substantially due to measurement error and regression to the mean. We aimed to determine whether studies of predictors of response should adjust for baseline HbA1c. Methods We assessed the relationship between baseline HbA1c and glycaemic response in 257 participants treated with GLP-1R agonists and assessed whether it reflected measurement error and regression to the mean using duplicate ‘pre-baseline’ HbA1c measurements not included in the response variable. In this cohort and an additional 2659 participants treated with sulfonylureas we assessed the relationship between covariates associated with baseline HbA1c and treatment response with and without baseline adjustment, and with a bias correction using pre-baseline HbA1c to adjust for the effects of error in baseline HbA1c. Results Baseline HbA1c was a major predictor of response (R2 = 0.19,β = -0.44,pHbA1c were associated with response, however these associations were weak or absent after adjustment for baseline HbA1c. Bias correction did not substantially alter associations. Conclusions Adjustment for the baseline HbA1c measurement is a simple and effective way to reduce bias in studies of predictors of response to glucose lowering therapy. PMID:27050911

Sistemas de producción agrícola sostenible

Directory of Open Access Journals (Sweden)

Róger Martínez Castillo

2009-01-01

Full Text Available El desarrollo sostenible se fundamenta en principios éticos, como el respeto y armonía con la naturaleza; valores políticos, como la democracia participativa y equidad social; y normas morales, como racionalidad ambiental. El desarrollo sostenible es igualitario, descentralizado y autogestionario, capaz de satisfacer las necesidades básicas de la población, respetando la diversidad cultural y mejorando la calidad de vida. La agricultura y el desarrollo sostenible se refieren a la necesidad de minimizar la degradación de la tierra agrícola, maximizando a su vez la producción. Este considera el conjunto de las actividades agrícolas, como el manejo de suelos y aguas,el manejo de cultivos y la conservación de la biodiversidad; considerando a su vez el suministro de alimentos y materias primas. La sostenibilidad de los sistemas de producción agrícola se refiere a la capacidad del sistema para mantener su productividad a pesar de las perturbaciones económicas y naturales, externas o internas. La sostenibilidad es función de las características naturales del sistema y las presiones e intervenciones que sufre, así como aquellas intervenciones sociales, económicas y técnicas que se hacen para contrarrestar presiones negativas; destacándose la resiliencia del sistema.

Modelos de vulnerabilidad agrícola ante los efectos del cambio climático

Directory of Open Access Journals (Sweden)

Claudia Hernández Ramírez

2014-12-01

Full Text Available La Vulnerabilidad Agrícola (VA es el resultado de la medición de la variabilidad climática dentro de un contexto de vulnerabilidad social y sectorial, que ha ido agregando conceptos e indicadores que enriquecen y complementan el análisis de la seguridad alimentaria, en el entendido que la disponibilidad de un pronóstico corresponde no solo al derecho primordial de cualquier ser humano, sino a la supervivencia del mismo. La metodología de medición de esta variable depende estrictamente del alcance de la investigación y de la disponibilidad de datos de la región y del producto agrícola seleccionado. Los modelos utilizados hasta la fecha son tres: el modelo Estructural, el modelo Espacial y la Vulnerabilidad Agrícola.

A Revolução Agrária Cubana: conquistas e desafios

Directory of Open Access Journals (Sweden)

Juan Valdés Paz

2011-01-01

Full Text Available Após o triunfo da Revolução em 1959, iniciou-se uma profunda transformação da sociedade cubana, primeiro política, depois social e, desde muito cedo, agrária. A Revolução Cubana foi a superação da questão agrária originada na etapa republicana e uma opção socialista para o desenvolvimento socioeconômico do país, do qual o desenvolvimento agrário tem sido um eixo fundamental. A superação dessa "questão agrária" do socialismo cubano determina as estratégias em curso e suas metas imediatas. Como parte desse processo, examinamos seis aspectos que caracterizaram seu desenvolvimento; são eles: a estrutura da pose de terra; o uso do solo; a organização agrária; o modelo tecnológico; a economia agrária; e o desenvolvimento da sociedade rural.Con el triunfo de la Revolución en 1959, se inició una profunda transformación de la sociedad cubana, primero política, después social y desde muy tempranamente, agraria. La Revolución Cubana fue la superación de la cuestión agraria originada en la etapa republicana y una opción socialista para el desarrollo socioeconómico del país, del cual el desarrollo agrario ha sido un eje fundamental. La superación de esta "cuestión agraria" del socialismo cubano, determina las estrategias en curso y sus metas inmediatas. Como parte de ese proceso, se examinan seis de los aspectos que caracterizaron su desarrollo, a saber: la estructura de tenencia de la tierra; el uso del suelo; la organización agraria; el modelo tecnológico; la economía agraria; y el desarrollo de la sociedad rural.After the triumph of the revolution in 1959, a profound transformation of Cuban society began - first political, then social and, very early on, agrarian. The Cuban Revolution surmounted the agrarian issue that had originated during the republican phase and embodied a socialist option for socioeconomic development (of which agricultural development was a fundamental part. Cuban socialism's efforts to

Measurements of fuel temperature coefficient of reactivity on a commercial AGR

International Nuclear Information System (INIS)

Telford, A.; Bridge, M.J.

1978-01-01

Tests have been carried out on the commercial AGR at Hikley Point to determine the fuel temperature coefficient of reactivity, an important safety related parameter. Reactor neutron flux was measured during transients induced by movement of a bank of control rods from one steady position to another. An inverse kinetics analysis was applied to the measured flux to determine the change which occured in core reactivity as the fuel temperature changed. The variation of mean fuel temperature was deduced from the flux transient by means of a nine-plane thermal hydraulics representation of the AGR fuel channel. Results so far obtained confirm the predicted variation of fuel temperature coefficient with butn-up. (author)

Green Fluorescent Protein (GFP-Based Overexpression Screening and Characterization of AgrC, a Receptor Protein of Quorum Sensing in Staphylococcus aureus

Directory of Open Access Journals (Sweden)

Shengdi Fan

2013-09-01

Full Text Available Staphylococcus aureus AgrC is an important component of the agr quorum-sensing system. AgrC is a membrane-embedded histidine kinase that is thought to act as a sensor for the recognition of environmental signals and the transduction of signals into the cytoplasm. However, the difficulty of expressing and purifying functional membrane proteins has drastically hindered in-depth understanding of the molecular structures and physiological functions of these proteins. Here, we describe the high-yield expression and purification of AgrC, and analyze its kinase activity. A C-terminal green fluorescent protein (GFP fusion to AgrC served as a reporter for monitoring protein expression levels in real time. Protein expression levels were analyzed by the microscopic assessment of the whole-cell fluorescence. The expressed AgrC-GFP protein with a C-terminal His-tagged was purified using immobilized metal affinity chromatography (IMAC and size exclusion chromatography (SEC at yields of ≥10 mg/L, following optimization. We also assessed the effects of different detergents on membrane solubilization and AgrC kinase activity, and polyoxyethylene-(23-lauryl-ether (Brij-35 was identified as the most suitable detergent. Furthermore, the secondary structural stability of purified AgrC was analyzed using circular dichroism (CD spectroscopy. This study may serve as a general guide for improving the yields of other membrane protein preparations and selecting the appropriate detergent to stabilize membrane proteins for biophysical and biochemical analyses.

Efeito de doses de gesso agrícola na cultura do milho e alterações químicas no solo

Directory of Open Access Journals (Sweden)

Luiz Augusto Amaral

2017-04-01

Full Text Available A cultura do milho apresenta importância econômica no cenário agrícola, de modo que a região Centro Oeste detém a maior media de produtividade do Brasil. O objetivo deste estudo foi avaliar o efeito de doses de gesso agrícola sobre a produtividade de milho cultivado em segunda safra e seus efeitos químicos no solo. O experimento foi realizado no Campus experimental da UNEMAT, Tangará da Serra – MT. O delineamento experimental foi em blocos casualizados (DBC com cinco tratamentos (0 kg ha-1, 1.000 kg ha-1, 2.000 kg ha-1, 3.000 kg ha-1 e 4.000 kg ha-1 de gesso agrícola com quatro repetições, totalizando 20 parcelas. Foi utilizado o híbrido de milho DKB 390 VT Pro2, e as parcelas foram constituídas de cinco metros de comprimento por quatro de largura, com espaçamento entre linhas de 0,50 m. Foi aplicado calcário dolomítico e gesso agrícola aos 60 e 30 dias antes da semeadura, respectivamente. Somente a variável diâmetro do caule e produtividade apresentou diferença significativa entre os tratamentos, onde os diâmetros superiores foram observados nas doses acima 2.000 kg ha-1 e a maior produtividade obtida na dose de 4.000 kg ha-1 de gesso. O efeito da aplicação do gesso proporcionou aumento na concentração de enxofre, cálcio e magnésio no subsolo, assim como redução nos teores de alumino. A dose de 4.000 kg ha-1 de gesso promoveu a maior produtividade.

Diagnósticos de las apuestas productivas para seis productos del sector agrícola en Colombia

OpenAIRE

Quintero Rubio, Paula Vanesa; Rubio Rodriguez, Juan Camilo

2014-01-01

El documento “Diagnósticos de las apuestas productivas para seis productos del sector agrícola en Colombia”, pretende proporcionar herramientas para el incremento productivo de seis productos agrícolas con un alto potencial en el país, mediante la identificación de mercados internacionales factibles, el análisis de sus procesos de producción y la comparación de eficiencia en costos del transporte de mercancía a nivel nacional; buscando el aumento de la participación del PIB agrícola en el PI...

Programa computacional para calcular a potência requerida de máquinas e implementos agrícolas

OpenAIRE

Pablo Pereira Corrêa Klaver; Ricardo Ferreira Garcia; José Francisco Sá Vasconcelos Júnior; Delorme Corrêa Junior; Wellington Gonzaga Vale

2013-01-01

O uso de programas computacionais no setor agrícola permite atingir objetivos específicos na área. Dentre esses, um dos mais complexos é a seleção adequada de máquinas e implementos agrícolas visando à otimização de operações agrícolas, devido, principalmente, à grande variedade de equipamentos existentes no mercado e a gama de tarefas e situações de trabalho que estas são submetidas no campo. O objetivo deste trabalho foi desenvolver um programa computacional para calcular a potência requeri...

Programa computacional para calcular a potência requerida de máquinas e implementos agrícolas

Directory of Open Access Journals (Sweden)

Pablo Pereira Corrêa Klaver

2013-12-01

Full Text Available O uso de programas computacionais no setor agrícola permite atingir objetivos específicos na área. Dentre esses, um dos mais complexos é a seleção adequada de máquinas e implementos agrícolas visando à otimização de operações agrícolas, devido, principalmente, à grande variedade de equipamentos existentes no mercado e a gama de tarefas e situações de trabalho que estas são submetidas no campo. O objetivo deste trabalho foi desenvolver um programa computacional para calcular a potência requerida de máquinas e implementos agrícolas normalmente utilizados na condução de operações de campo, desde o preparo do solo até as operações de implantação de culturas. Desenvolvido em linguagem PHP, o programa computacional baseia-se na norma ASAE D497.4 - Agricultural Machinery Management Data como referência para desenvolvimento de cálculos. A partir do programa desenvolvido, tornou-se possível a execução de tarefas para cálculos de avaliação da demanda de potência de máquinas e implementos agrícolas de forma simplificada pela internet.

41 CFR 109-1.5202 - Establishment of a personal property holdings baseline.

Science.gov (United States)

2010-07-01

... personal property holdings baseline. 109-1.5202 Section 109-1.5202 Public Contracts and Property Management...-1.5202 Establishment of a personal property holdings baseline. (a) If the contractor is a new... baseline or may perform a complete physical inventory of all personal property. This physical inventory is...

PRAPRAG: software para planejamento racional de máquinas agrícolas

OpenAIRE

Mercante,Erivelto; Souza,Eduardo G. de; Johann,Jerry A; Gabriel Filho,Antonio; Uribe-Opazo,Miguel A

2010-01-01

O software PRAPRAG é uma ferramenta de escolha de máquinas e implementos agrícolas que apresentam o menor custo por área ou por quantidade produzida, bem como, faz o planejamento de aquisição das máquinas para a propriedade agrícola, do ponto de vista técnico e econômico. Foi utilizada a linguagem de programação Borland Delphi 3.0 e, a partir de prospectos das máquinas e implementos, criou-se um banco de dados onde o usuário pode cadastrar e modificar suas características de uso. O software m...

ART Or AGR: Deciphering Which Reserve Program is Best Suited for Today’s Total Force Structure

Science.gov (United States)

2016-02-01

AIR COMMAND AND STAFF COLLEGE AIR UNIVERSITY ART OR AGR: DECIPHERING WHICH RESERVE PROGRAM IS BEST SUITED FOR TODAY’S TOTAL FORCE STRUCTURE...4 ART Program...time workforce, which are the ART and AGR programs, by comparing each and highlighting the differences, advantages and disadvantages they present to

Laboratory electron exposure of TSS-1 thermal control coating

Science.gov (United States)

Vaughn, J. A.; Mccollum, M.; Carruth, M. R., Jr.

1995-01-01

RM400, a conductive thermal control coating, was developed for use on the exterior shell of the tethered satellite. Testing was performed by the Engineering Physics Division to quantify effects of the space environment on this coating and its conductive and optical properties. Included in this testing was exposure of RM400 to electrons with energies ranging from 0.1 to 1 keV, to simulate electrons accelerated from the ambient space plasma when the tethered satellite is fully deployed. During this testing, the coating was found to luminesce, and a prolonged exposure of the coating to high-energy electrons caused the coating to darken. This report describes the tests done to quantify the degradation of the thermal control properties caused by electron exposure and to measure the luminescence as a function of electron energy and current density to the satellite.

Fabrication of Uranium Oxycarbide Kernels for HTR Fuel

International Nuclear Information System (INIS)

Barnes, Charles; Richardson, Clay; Nagley, Scott; Hunn, John; Shaber, Eric

2010-01-01

Babcock and Wilcox (B and W) has been producing high quality uranium oxycarbide (UCO) kernels for Advanced Gas Reactor (AGR) fuel tests at the Idaho National Laboratory. In 2005, 350-(micro)m, 19.7% 235U-enriched UCO kernels were produced for the AGR-1 test fuel. Following coating of these kernels and forming the coated-particles into compacts, this fuel was irradiated in the Advanced Test Reactor (ATR) from December 2006 until November 2009. B and W produced 425-(micro)m, 14% enriched UCO kernels in 2008, and these kernels were used to produce fuel for the AGR-2 experiment that was inserted in ATR in 2010. B and W also produced 500-(micro)m, 9.6% enriched UO2 kernels for the AGR-2 experiments. Kernels of the same size and enrichment as AGR-1 were also produced for the AGR-3/4 experiment. In addition to fabricating enriched UCO and UO2 kernels, B and W has produced more than 100 kg of natural uranium UCO kernels which are being used in coating development tests. Successive lots of kernels have demonstrated consistent high quality and also allowed for fabrication process improvements. Improvements in kernel forming were made subsequent to AGR-1 kernel production. Following fabrication of AGR-2 kernels, incremental increases in sintering furnace charge size have been demonstrated. Recently small scale sintering tests using a small development furnace equipped with a residual gas analyzer (RGA) has increased understanding of how kernel sintering parameters affect sintered kernel properties. The steps taken to increase throughput and process knowledge have reduced kernel production costs. Studies have been performed of additional modifications toward the goal of increasing capacity of the current fabrication line to use for production of first core fuel for the Next Generation Nuclear Plant (NGNP) and providing a basis for the design of a full scale fuel fabrication facility.

Experience of iodine, caesium and noble gas release from AGR failures

International Nuclear Information System (INIS)

Chapman, C.J.; Harris, A.M.; Phillips, M.E.

1985-01-01

In the event of a fuel failure in an Advanced Gas Cooled Reactor (AGR), the quantity of fission products available for release to the environment is determined by the transport of fission products in the UO 2 fuel, by the possible retention of fission products in the fuel can interspace and by the deposition of fission products on gas circuit surfaces ('plate-out'). The fission products of principal radiological concern are radioactive caesium (Cs-137 and Cs-134) and iodine (principally I-131). Results are summarised of a number of experiments which were designed to study the release of these fission products from individual fuel failures in the prototype AGR at Windscale. Results are also presented of fission product release from failures in commercial AGRs. Comparisons of measured releases of caesium and iodine relative to the release of the noble gas fission products show that, for some fuel failures, there is a significant retention of caesium and iodine within the fuel can interspace. Under normal conditions circuit deposition reduces caesium and iodine gas concentrations by several orders of magnitude. Differing release behaviour of caesium and iodine from the failures is examined together with subsequent deposition within the sampling equipment. These observations are important factors which must be considered in developing an understanding of the mechanisms involved in circuit deposition. (author)

Necesidades educacionales sobre riesgo de plaguicidas en el contexto socio-ambiental de las comunidades agrícolas de Sonora

OpenAIRE

M.I. Silveira Gramont; L. Aldana Madrid; A.I. Valenzuela Quintanar; C.B. Ochoa Nogales; G. Jasa-Silveira; Beatriz Camarena Gómez

2016-01-01

Para proponer estrategias de educación y comunicación sobre plaguicidas en las comunidades agrícolas de Sonora, se requiere situar la problemática de la exposición a plaguicidas en el contexto socio-cultural y ambiental de las comunidades afectadas, tomando en cuenta los factores que contribuyen al mayor riesgo de exposición de los trabajadores agrícolas y de sus familias. Este estudio examina los factores poblacionales, educacionales, culturales y de trabajo de habitantes y trabajadores agrí...

Coated-platelets predict stroke at 30 days following TIA.

Science.gov (United States)

Kirkpatrick, Angelia C; Vincent, Andrea S; Dale, George L; Prodan, Calin I

2017-07-11

To examine the potential for coated-platelets, a subset of highly procoagulant platelets observed on dual agonist stimulation with collagen and thrombin, for predicting stroke at 30 days in patients with TIA. Consecutive patients with TIA were enrolled and followed up prospectively. ABCD2 scores were obtained for each patient. Coated-platelet levels, reported as percent of cells converted to coated-platelets, were determined at baseline. The primary endpoint was the occurrence of stroke at 30 days. Receiver operator characteristic (ROC) analysis was used to calculate area under the curve (AUC) values for a model including coated-platelets to predict incident stroke at 30 days. A total of 171 patients with TIA were enrolled, and 10 strokes were observed at 30 days. A cutoff of 51.1% for coated-platelet levels yielded a sensitivity of 0.80 (95% confidence interval [CI] 0.55-1.0), specificity of 0.73 (95% CI 0.66-0.80), positive predictive value of 0.16 (95% CI 0.06-0.26), and negative predictive value of 0.98 (95% CI 0.96-1.0). The adjusted hazard ratio of incident stroke in patients with coated-platelet levels ≥51.1% was 10.72 compared to those with levels TIA. © 2017 American Academy of Neurology.

O impacto do trabalho infantil no setor agrícola sobre a saúde

Directory of Open Access Journals (Sweden)

Alexandre Chibebe Nicolella

2008-09-01

Full Text Available O objetivo desse artigo é verificar se o trabalho infantil no setor agrícola produz impacto negativo sobre a saúde. Para a análise foram utilizadas as PNADs (Pesquisas Nacionais por Amostra de Domicílios de 1998 e 2003, que trazem suplemento especial sobre saúde, empregando a técnica econométrica de pseudo-painel. Assim, foram consideradas as crianças de 5 a 15 anos em 1998 e de 10 a 20 anos em 2003. Os resultados mostram que, para os indivíduos economicamente ativos, a atividade no setor agrícola e o trabalho de risco no setor agrícola não diferem dos outros setores, ou seja, trabalhar no setor agrícola não impõe um maior desgaste à saúde em relação aos outros setores da economia. Se considerados todos os indivíduos economicamente ativos, os resultados mostram que o trabalho agrícola não afeta a saúde e que o trabalho não-agrícola tem impacto negativo. Dessa forma, acredita-se que a atuação do governo deve ser setorial, visando uma melhoria no acesso ao sistema de saúde, bem como aos medicamentos, e a promoção da educação materna com relação à saúde.The aim of this dissertation is to identify the causal relation between rural child labour and health. The analysis utilized the PNAD, a Brazilian household survey, from 1998 and 2003. The econometric modeling was based on the pseudo-panel approach and was considered the children from 5 to 15 years old in 1998 and from 10 to 20 years old in 2003. The results show that work and work in risky jobs in the agricultural sector do not differ from those impacts of other sectors. It was also presented, for all individuals that work in the agricultural sector does not impact the health capital and work in the non rural sector impact negatively the health capital. So, the government intervention in rural areas should be different from the one implemented on the urban area to mitigate the impact of child labour on health and also, the government intervention should be

IUE observations of the hot components in two symbiotic stars. [R Agr and RW Hya, 1200 to 3200 A

Energy Technology Data Exchange (ETDEWEB)

Michalitsianos, A G [National Aeronautics and Space Administration, Greenbelt, MD (USA). Goddard Space Flight Center; Kafatos, M; Hobbs, R W; Maran, S P

1980-03-13

Ultraviolet measurements in the 1,200 - 3,200 A range are reported on two symbiotic stars, R Agr and RW Hya. The results indicate the presence of a hot component in each star, supporting the view that each is a binary system with a luminous red primary and a hot, sub-luminous companion. In the case of RW Hya the hot companion manifests itself by exciting a compact nebulosity while in the case of R Agr it is believed that the continuous spectrum of the hot star is directly detected, while the continuum of nebulosity excited by the hot star is detected at longer wavelengths.

Modelagem matemática para seleção de conjuntos mecanizados agrícolas pelo menor custo operacional

OpenAIRE

Baio,Fábio H. R.; Rodrigues,Andrew D.; Santos,Gilson S. dos; Silva,Simone P. da

2013-01-01

A seleção de uma máquina agrícola pode tornar-se uma tarefa árdua, pois há diversas variáveis que devem ser consideradas. A escolha do equipamento mais adequado para uma propriedade agrícola é uma das etapas mais importantes do processo produtivo. O objetivo deste trabalho foi desenvolver um modelo de computador por programação linear em plataforma web para seleção automatizada de conjuntos mecanizados agrícolas, baseados no menor custo operacional. O programa, desenvolvido em linguagem ASP.N...

Linear peptidomimetics as potent antagonists of Staphylococcus aureus agr quorum sensing

DEFF Research Database (Denmark)

Karathanasi, Georgia; Bojer, Martin Saxtorph; Baldry, Mara

2018-01-01

Staphylococcus aureus is an important pathogen causing infections in humans and animals. Increasing problems with antimicrobial resistance has prompted the development of alternative treatment strategies, including antivirulence approaches targeting virulence regulation such as the agr quorum...

Sensitivity Evaluation of the Daily Thermal Predictions of the AGR-1 Experiment in the Advanced Test Reactor

Energy Technology Data Exchange (ETDEWEB)

Grant Hawkes; James Sterbentz; John Maki

2011-05-01

A temperature sensitivity evaluation has been performed for the AGR-1 fuel experiment on an individual capsule. A series of cases were compared to a base case by varying different input parameters into the ABAQUS finite element thermal model. These input parameters were varied by ±10% to show the temperature sensitivity to each parameter. The most sensitive parameters are the outer control gap distance, heat rate in the fuel compacts, and neon gas fraction. Thermal conductivity of the compacts and graphite holder were in the middle of the list for sensitivity. The smallest effects were for the emissivities of the stainless steel, graphite, and thru tubes. Sensitivity calculations were also performed varying with fluence. These calculations showed a general temperature rise with an increase in fluence. This is a result of the thermal conductivity of the fuel compacts and graphite holder decreasing with fluence.

MicroRNA-1291 targets the FOXA2-AGR2 pathway to suppress pancreatic cancer cell proliferation and tumorigenesis

Science.gov (United States)

Qiu, Jing-Xin; Kim, Edward J.; Yu, Ai-Ming

2016-01-01

Pancreatic cancer is the fourth leading cause of cancer death in the United States. Better understanding of pancreatic cancer biology may help identify new oncotargets towards more effective therapies. This study investigated the mechanistic actions of microRNA-1291 (miR-1291) in the suppression of pancreatic tumorigenesis. Our data showed that miR-1291 was downregulated in a set of clinical pancreatic carcinoma specimens and human pancreatic cancer cell lines. Restoration of miR-1291 expression inhibited pancreatic cancer cell proliferation, which was associated with cell cycle arrest and enhanced apoptosis. Furthermore, miR-1291 sharply suppressed the tumorigenicity of PANC-1 cells in mouse models. A proteomic profiling study revealed 32 proteins altered over 2-fold in miR-1291-expressing PANC-1 cells that could be assembled into multiple critical pathways for cancer. Among them anterior gradient 2 (AGR2) was reduced to the greatest degree. Through computational and experimental studies we further identified that forkhead box protein A2 (FOXA2), a transcription factor governing AGR2 expression, was a direct target of miR-1291. These results connect miR-1291 to the FOXA2-AGR2 regulatory pathway in the suppression of pancreatic cancer cell proliferation and tumorigenesis, providing new insight into the development of miRNA-based therapy to combat pancreatic cancer. PMID:27322206

The safety of the AGR

International Nuclear Information System (INIS)

Dale, G.C.; Bowerman, J.M.

1982-01-01

The publication is in 10 parts. Section 1 describes regulatory control of the nuclear industry in the UK and outlines the principal Acts of Parliament and international regulations currently in force in the licensing of nuclear power stations. Section 2 discusses the responsibilities laid on licensees of nuclear sites for ensuring the safety of their employees and members of the public. In Section 3, a comprehensive description of the Advanced Gas-cooled Reactor (AGR) system and its principal components is given. The safety features are described in Section 4. Radiological effects are described in Section 5. Section 6 explains how different types of radioactive wastes arise and describes their management and plans for their long-term disposal. Section 7 deals with the transportation of fuel and radioactive waste. Section 8 is devoted to fault conditions; the steps taken to ensure adequate protection against faults and the reliability of plant are described. Liaison with local communities is discussed in Section 9; the role of the Local Liaison Committees is described and details of emergency plans are given. The final section covers the decommissioning and dismantling of power stations after they have reached the end of their useful lives. (author)

Chemical cleaning of AGR boilers

International Nuclear Information System (INIS)

Moore, S.V.; Moore, W.; Rantell, A.

1978-01-01

AGR boilers are likely to require post service chemical cleaning to remove accumulated oxides at intervals of 15 - 35 kh. The need to clean will be based on an assessment of such factors as the development of flow imbalances through parallel tubes induced by the formation of rough oxide surfaces, an increasing risk of localised corrosion as the growth of porous oxides proceeds and the risk of tube blockage caused by the exfoliation of steam-grown oxides. The study has shown what heterogeneous multilayer oxides possessing a range of physical and chemical properties form on the alloy steels. They include porous and compact magnetites, chromium spinels and sesquioxide. Ammoniated citric acid has been shown to remove deposited and water-grown magnetites from the carbon and alloy steels but will not necessarily remove the substituted spinels grown on the alloy steels or the potentially spalling steam-grown magnetite on the A1SI 316 superheater. Citric acid supplemented with the reducing agent glyoxal completely removes all oxides from the boiler except the protective inner spinel formed on the 316. Removal of the spinels and compact magnetites occurs more by undercutting and physical detachment than by the dissolution. (author)

Trace organics in AGR coolants

International Nuclear Information System (INIS)

Smith, R.; Green, L.O.; Johnson, P.A.V.

1980-01-01

Several analytical techniques have been employed in previous studies of the stable organic compounds arising from the radiolysis of methane/carbon monoxide/carbon dioxide coolants. The majority of this early information was collected from the Windscale AGR prototype. Analyses were also carried out on the liquors obtained from the WAGR humidryers. Three classes of compound were found in the liquors; aliphatic acids in the aqueous phase and methyl ketones and aromatic hydrocarbons in the oily phase. Acetic acid was found to be the predominant carboxylic acid. This paper outlines the major findings from a recent analytical survey of coolants taken over a wide range of dose rate, pressure, temperature and composition, from materials testing reactor facilities, WAGR and CAGR. (author)

Corrective action baseline report for underground storage tank 2331-U Building 9201-1

International Nuclear Information System (INIS)

1994-01-01

The purpose of this report is to provide baseline geochemical and hydrogeologic data relative to corrective action for underground storage tank (UST) 2331-U at the Building 9201-1 Site. Progress in support of the Building 9201-1 Site has included monitoring well installation and baseline groundwater sampling and analysis. This document represents the baseline report for corrective action at the Building 9201-1 site and is organized into three sections. Section 1 presents introductory information relative to the site, including the regulatory initiative, site description, and progress to date. Section 2 includes the summary of additional monitoring well installation activities and the results of baseline groundwater sampling. Section 3 presents the baseline hydrogeology and planned zone of influence for groundwater remediation

AGR-2 Final Data Qualification Report for U.S. Capsules - ATR Cycles 147A Through 154B

Energy Technology Data Exchange (ETDEWEB)

Pham, Binh T. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Very High-Temperature Reactor Technology Development Office; Einerson, Jeffrey J. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Very High-Temperature Reactor Technology Development Office

2014-07-01

This report provides the data qualification status of AGR-2 fuel irradiation experimental data in four U.S. capsules from all 15 Advanced Test Reactor (ATR) Cycles 147A, 148A, 148B, 149A, 149B, 150A, 150B, 151A, 151B, 152A, 152B, 153A, 153B, 154A, and 154B, as recorded in the Nuclear Data Management and Analysis System (NDMAS). Thus, this report covers data qualification status for the entire AGR-2 irradiation and will replace four previously issued AGR-2 data qualification reports (e.g., INL/EXT-11-22798, INL/EXT-12-26184, INL/EXT-13-29701, and INL/EXT-13-30750). During AGR-2 irradiation, two cycles, 152A and 153A, occurred when the ATR core was briefly at low power, so AGR-2 irradiation data are not used for physics and thermal calculations. Also, two cycles, 150A and 153B, are Power Axial Locator Mechanism (PALM) cycles when the ATR power is higher than during normal cycles. During the first PALM cycle, 150A, the experiment was temporarily moved from the B-12 location to the ATR water canal and during the second PALM cycle, 153B, the experiment was temporarily moved from the B-12 location to the I-24 location to avoid being overheated. During the “Outage” cycle, 153A, seven flow meters were installed downstream from seven Fission Product Monitoring System (FPMS) monitors to measure flows from the monitors and these data are included in the NDMAS database.

Propuesta para llevar al espacio académico institucional, saberes agrícolas tradicionales

OpenAIRE

Gómez Espinoza, José Antonio

2007-01-01

Este texto se presentó como comunicación al II Congreso Internacional de Etnografía y Educación: Migraciones y Ciudadanías. Universidad Autónoma de Barcelona, Barcelona, 5-8 Septiembre 2008. Mientras en las “milpas” campesinas se practican saberes agrícolas tradicionales (SAT) para la subsistencia campesina a través de la producción de maíz y cultivos asociados (milpa), en las Instituciones de Enseñanza Agrícola Superior del país, se enseña un enorme bagaje científico y tecnológico sin con...

Seroprevalencia de brucelosis en trabajadores agrícolas de las comarcas costeras de Castellón, España

Directory of Open Access Journals (Sweden)

Villamarín-Vázquez José Luis

2002-01-01

Full Text Available Objetivo. Determinar la seroprevalencia de brucelosis en trabajadores agrícolas. Material y métodos. Estudio transversal efectuado durante 1996 y 1997 en la Unidad de Salud Laboral del Centro de Salud Pública (CSP de Castellón, España, con 482 aspirantes a su acreditación como manipulador de plaguicidas para aplicación agrícola y a quienes se les hicieron las pruebas serológicas de rosa de Bengala, seroaglutinación de Wright y Coombs antibrucela. En el análisis estadístico se estimó la prevalencia y se usó regresión logística. Resultados. 15 personas (3.1%, IC 95% 1.8%-5.1% presentaron títulos de 1/40 o mayores a las pruebas de Wright o Coombs, y todas negativas al rosa de Bengala. No se apreció riesgo profesional elevado. Conclusiones. La prevalencia estimada fue baja.

Coating optimization for the ATHENA+ mission

DEFF Research Database (Denmark)

Ferreira, Desiree Della Monica; Christensen, Finn Erland; Jakobsen, Anders Clemen

2013-01-01

The ATHENA mission concept, now called ATHENA+, continues to be refined to address important questions in modern astrophysics. Previous studies have established that the requirement for effective area can be achieved using a combination of bi-layer coatings and/or simple graded multilayers. We find...... that further coating developments can improve on the baseline specifications and present here preliminary results on the optimization of coating design based on the new specifications of the ATHENA+ mission. The performances of several material combinations are investigated with the goal of maximizing...

Chemical cleaning of UK AGR boilers

International Nuclear Information System (INIS)

Rudge, A.; Turner, P.; Ghosh, S.; Clary, W.; Tice, D.R.

2002-01-01

For a number of years, the waterside pressure drops across the advanced gas-cooled reactor (AGR) pod boilers have been increasing. The pressure drop increases have accelerated with time, which is the converse behaviour to that expected for rippled magnetite formation (rapid initial increase slowing down with time). Nonetheless, magnetite deposition remains the most likely cause for the increasing boiler resistances. A number of potential countermeasures have been considered in response to the boiler pressure drop increases. However, there was no detectable reduction in the rate of pressure drop increase. Chemical cleaning was therefore considered and a project to substantiate and then implement chemical cleaning was initiated. (authors)

Performance of multilayer coated silicon pore optics

Science.gov (United States)

Ackermann, M. D.; Collon, M. J.; Jensen, C. P.; Christensen, F. E.; Krumrey, M.; Cibik, L.; Marggraf, S.; Bavdaz, M.; Lumb, D.; Shortt, B.

2010-07-01

The requirements for the IXO (International X-ray Observatory) telescope are very challenging in respect of angular resolution and effective area. Within a clear aperture with 1.7 m > R > 0.25 m that is dictated by the spacecraft envelope, the optics technology must be developed to satisfy simultaneously requirements for effective area of 2.5 m2 at 1.25 keV, 0.65 m2 at 6 keV and 150 cm2 at 30 keV. The reflectivity of the bare mirror substrate materials does not allow these requirements to be met. As such the IXO baseline design contains a coating layout that varies as a function of mirror radius and in accordance with the variation in grazing incidence angle. The higher energy photon response is enhanced through the use of depth-graded multilayer coatings on the inner radii mirror modules. In this paper we report on the first reflectivity measurements of wedged ribbed silicon pore optics mirror plates coated with a depth graded W/Si multilayer. The measurements demonstrate that the deposition and performance of the multilayer coatings is compatible with the SPO production process.

Profissão, escola e campo: um estudo sobre o Ensino Técnico Agrícola

OpenAIRE

Martins-Salandim, Maria Ednéia [UNESP; Garnica, Antonio Vicente Marafioti [UNESP

2010-01-01

Apresentando uma síntese histórico-sociológica do panorama rural brasileiro, da constituição do ensino técnico, e do desenvolvimento do ensino técnico agrícola, este artigo defende que as escolas técnicas agrícolas sofrem uma dupla marginalização, por um lado proveniente de sua natureza profissionalizante e, por outro, dada sua vinculação com o meio rural brasileiro.

A computer model to predict temperatures and gas flows during AGR fuel handling

International Nuclear Information System (INIS)

Bishop, D.C.; Bowler, P.G.

1986-01-01

The paper describes the development of a comprehensive computer model (HOSTAGE) that has been developed for the Heysham II/Torness AGRs to predict temperature transients for all the important components during normal and fault conditions. It models not only the charge and discharge or fuel from an on-load reactor but also follows the fuel down the rest of the fuel route until it is dismantled. The main features of the physical model of gas and heat flow are described. Experimental results are used where appropriate and an indication will be given of how the predictions by HOSTAGE correlate with operating AGR reactors. The role of HOSTAGE in the Heysham II/Torness safety case is briefly discussed. (author)

Performance of multilayer coated silicon pore optics

DEFF Research Database (Denmark)

Ackermann, M. D.; Collon, M. J.; Cooper-Jensen, Carsten P.

2010-01-01

simultaneously requirements for effective area of 2.5 m2 at 1.25 keV, 0.65 m2 at 6 keV and 150 cm2 at 30 keV. The reflectivity of the bare mirror substrate materials does not allow these requirements to be met. As such the IXO baseline design contains a coating layout that varies as a function of mirror radius...

Impactos do Protocolo de Cartagena sobre o Comércio de Commodities Agrícolas

OpenAIRE

Borges, Izaías de Carvalho; Silveira, Jose Maria Ferreira Jardim da; Vieira Filho, José Eustáquio; Pereira, Andrea M.

2015-01-01

O Protocolo de Cartagena sobre Biossegurança é um acordo ambiental que agrega 132 países. O Protocolo tem impactos sobre o comércio de commodities agrícolas, porque estabelece regras para o transporte entre fronteiras de organismos vivos modificados (OVMs). O Artigo 18.2(a) do Protocolo refere-se às formas de identificação dos OVMs nos carregamentos de commodities agrícolas. O fato de que os principais países exportadores de grãos também sejam produtores de cultivares geneticamente modificado...

A “questão agrária” em Mariátegui

Directory of Open Access Journals (Sweden)

Frederico Daia Firmiano

2012-05-01

Full Text Available Neste breve artigo temos como objetivo refletir sobre a “questão agrária” no pensamento de José Carlos Mariátegui, sobretudo a partir de sua principal obra, os “Sete ensaios de interpretação da realidade peruana”. Nosso argumento é que o socialista peruano não tratou os problemas da formação social peruana a partir da chave teórica dada pela “questão agrária”, mas a encontrou no curso de uma interpretação marxista, profundamente original e inventiva, sobre esta formação social (desenvolvida ao lado da intensa militância política, identificando o problema indígena ao problema da terra, aos que Amauta conferiu uma alternativa socialista.

La Ingeniería Agrícola en el País

Directory of Open Access Journals (Sweden)

Bustamante M. Hellodoro

1985-12-01

Full Text Available Es sumamente difícil situar en la historia, el origen de la Ingeniería Agrícola, aunque podría remontarse al propio origen de la tierra, de las plantas y de las aguas. La Ingeniería Agrícola está ocupando un campo de acción que se ha desarrollado a pesar de las limitaciones que le ofrece el mismo desarrollo del país y al escepticismo sin fundamento de algunos pregoneros del pesimismo nacional; le corresponde enfrentar además hoy al cáncer del desempleo y a la falta de oportunidad para demostrar al país que la inversión hecha por el estado en la formación de estos profesionales es productiva.

AGR-5/6/7 LEUCO Kernel Fabrication Readiness Review

Energy Technology Data Exchange (ETDEWEB)

Marshall, Douglas W. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Fuel Design and Development; Bailey, Kirk W. [Idaho National Lab. (INL), Idaho Falls, ID (United States). ART Quality Assurance Engineer

2015-02-01

In preparation for forming low-enriched uranium carbide/oxide (LEUCO) fuel kernels for the Advanced Gas Reactor (AGR) fuel development and qualification program, Idaho National Laboratory conducted an operational readiness review of the Babcock & Wilcox Nuclear Operations Group – Lynchburg (B&W NOG-L) procedures, processes, and equipment from January 14 – January 16, 2015. The readiness review focused on requirements taken from the American Society Mechanical Engineers (ASME) Nuclear Quality Assurance Standard (NQA-1-2008, 1a-2009), a recent occurrence at the B&W NOG-L facility related to preparation of acid-deficient uranyl nitrate solution (ADUN), and a relook at concerns noted in a previous review. Topic areas open for the review were communicated to B&W NOG-L in advance of the on-site visit to facilitate the collection of objective evidences attesting to the state of readiness.

Uncertainty Quantification of Calculated Temperatures for the U.S. Capsules in the AGR-2 Experiment

Energy Technology Data Exchange (ETDEWEB)

Lybeck, Nancy [Idaho National Lab. (INL), Idaho Falls, ID (United States); Einerson, Jeffrey J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Pham, Binh T. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Hawkes, Grant L. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2015-03-01

A series of Advanced Gas Reactor (AGR) irradiation experiments are being conducted within the Advanced Reactor Technology (ART) Fuel Development and Qualification Program. The main objectives of the fuel experimental campaign are to provide the necessary data on fuel performance to support fuel process development, qualify a fuel design and fabrication process for normal operation and accident conditions, and support development and validation of fuel performance and fission product transport models and codes (PLN-3636). The AGR-2 test was inserted in the B-12 position in the Advanced Test Reactor (ATR) core at Idaho National Laboratory (INL) in June 2010 and successfully completed irradiation in October 2013, resulting in irradiation of the TRISO fuel for 559.2 effective full power days (EFPDs) during approximately 3.3 calendar years. The AGR-2 data, including the irradiation data and calculated results, were qualified and stored in the Nuclear Data Management and Analysis System (NDMAS) (Pham and Einerson 2014). To support the U.S. TRISO fuel performance assessment and to provide data for validation of fuel performance and fission product transport models and codes, the daily as-run thermal analysis has been performed separately on each of four AGR-2 U.S. capsules for the entire irradiation as discussed in (Hawkes 2014). The ABAQUS code’s finite element-based thermal model predicts the daily average volume-average fuel temperature and peak fuel temperature in each capsule. This thermal model involves complex physical mechanisms (e.g., graphite holder and fuel compact shrinkage) and properties (e.g., conductivity and density). Therefore, the thermal model predictions are affected by uncertainty in input parameters and by incomplete knowledge of the underlying physics leading to modeling assumptions. Therefore, alongside with the deterministic predictions from a set of input thermal conditions, information about prediction uncertainty is instrumental for the ART

El Título de Ingeniero Agrónomo

Directory of Open Access Journals (Sweden)

Universidad Nacional de Colombia Facultad de Agronomía

1941-08-01

Full Text Available Como es ocurrencia frecuente la controversia sobre la propiedad académica o el derecho que asiste a los profesionales que han cursado estudios superiores de Agronomía para usar el título de Ingenieros Agrónomos, es procedente aclarar este punto sobre todo hoy que en Colombia la carrera agronómica está ocupando destacada posición en el panorama social y económico del país.

Inverse kinetics technique for reactor shutdown measurement: an experimental assessment. [AGR

Energy Technology Data Exchange (ETDEWEB)

Lewis, T. A.; McDonald, D.

1975-09-15

It is proposed to use the Inverse Kinetics Technique to measure the subcritical reactivity as a function of time during the testing of the nitrogen injection systems on AGRs. A description is given of an experimental assessment of the technique by investigating known transients created by control rod movements on a small experimental reactor, (2m high, 1m radius). Spatial effects were observed close to the moving rods but otherwise derived reactivities were independent of detector position and agreed well with the existing calibrations. This prompted the suggestion that data from installed reactor instrumentation could be used to calibrate CAGR control rods.

Sostenibilidad de sistemas agrícolas Sustainability of farming systems

Directory of Open Access Journals (Sweden)

Leiva Fabio R.

1998-12-01

Full Text Available Las actividades agrícolas pueden tener impactos negativos sobre el ambiente, con efectos dentro y fuera de los predios. El presente artículo pretende contribuir al avance de la agricultura sostenible con énfasis en países en vías de desarrollo. Se revisan y analizan los conceptos de sostenibilidad y agricultura sostenible, incluyendo los diferentes puntos de vista en el debate sobre sostenibilidad'. El artículo examina los impactos ambientales debidos a las actividades agrícolas, destacando la importancia de fortalecer la investigación, con publicación de resultados, sobre la relación agricultura y medio ambiente. La complejidad de los factores que determinan la sostenibilidad agrícola exige una concepción de sistemas, integradora, participativa y holística. El uso de indicadores tiene un gran potencial en la evaluación de la sostenibilidad de sistemas productivos. La práctica de agricultura sostenible requiere tener en cuenta las condiciones ambientales, sociales y económicas en las cuales
se desenvuelve la agricultura.Farming activities have the potential to affect the farming system itself and the offfarm environment. This paper attempts to contribute to the development of sustainable agriculture with emphasis in developing countries. The concepts of sustainability and sustainable agriculture are reviewed and discussed, including the different viewpoints in the sustainability debate. Environmental impacts due to farming activities are examined emphasising the need of promoting further research and publication of findings on the links between environment and agriculture. The complexity of the factors that determine farming sustainability requires
a systematic, holistic, participative and integrated approach. Indicators are likely to contribute to the development of sustainable farming systems. Understanding environmental, social and economic circumstances is required to promote sustainability.

Puesta en Valor del Patrimonio Agrícola en Ciudades Intermedias, caso Chillán

Directory of Open Access Journals (Sweden)

Marcela Andrea Soto Caro

2016-12-01

Full Text Available Frente al actual escenario territorial, donde la ruralidad persiste en todas sus expresiones identitarias, sociales y económicas, el suelo agrícola pierde extensión, en una pugna constante por sobreponerse a la expansión urbana. Las modificaciones estructurales del espacio periurbano en las últimas décadas nos presentan la consolidación de los procesos de crecimiento y transformación urbana desiguales, que bajo el modelo neoliberal imperante y persistente, se hacen cada vez más visibles en las ciudades de rango intermedio. Si bien no tienen la escala metropolitana, adquieren velocidades de crecimiento urbano aún mayores. El presente estudio compara la evolución de indicadores relacionados con el desarrollo urbano del territorio, para analizar las dinámicas de crecimiento y la pérdida de suelo agrícola. Si bien las ciudades de rango intermedio promueven el consumo de suelo urbano, existe una oportunidad de resaltar el valor patrimonial y productivo del suelo agrícola.

The effect of a polyurethane coating incorporating both a thrombin inhibitor and nitric oxide on hemocompatibility in extracorporeal circulation

Science.gov (United States)

Major, Terry C.; Brisbois, Elizabeth J.; Jones, Anna M.; Zanetti, Margaux E.; Annich, Gail M.; Bartlett, Robert H.; Handa, Hitesh

2014-01-01

Nitric oxide (NO) releasing (NORel) materials have been extensively investigated to create localized increases in NO concentration by the proton driven diazeniumdiolate-containing polymer coatings and demonstrated to improve extracorporeal circulation (ECC) hemocompatibility. In this work, the NORel polymeric coating composed of a diazeniumdiolated dibutylhexanediamine (DBHD-N2O2)-containing hydrophobic Elast-eon™ (E2As) polyurethane was combined with a direct thrombin inhibitor, argatroban (AG), and evaluated in a 4 h rabbit thrombogenicity model without systemic anticoagulation. In addition, the immobilizing of argatroban to E2As polymer was achieved by either a polyethylene glycol-containing (PEGDI) or hexane methylene (HMDI) diisocyanate linker. The combined polymer film was coated on the inner walls of ECC circuits to yield significantly reduced ECC thrombus formation compared to argatroban alone ECC control after 4 h blood exposure (0.6 ± 0.1 AG/HMDI/NORel vs 1.7 ± 0.2 cm2 AG/HMDI control). Platelet count (2.8 ± 0.3 AG/HMDI/NORel vs 1.9 ± 0.1 × 108/ml AG/HMDI control) and plasma fibrinogen levels were preserved after 4 h blood exposure with both the NORel/argatroban combination and the AG/HMDI control group compared to baseline. Platelet function as measured by aggregometry remained near normal in both the AG/HMDI/NORel (63 ± 5%) and AG/HMDI control (58 ± 7%) groups after 3 h compared to baseline (77 ± 1%). Platelet P-selectin mean fluorescence intensity (MFI) as measured by flow cytometry also remained near baseline levels after 4 h on ECC to ex vivo collagen stimulation (16 ± 3 AG/HMDI/NORel vs 11 ± 2 MFI baseline). These results suggest that the combined AG/HMDI/NORel polymer coating preserves platelets in blood exposure to ECCs to a better degree than AG/PEGDI/NORel, NORel alone or AG alone. These combined antithrombin, NO-mediated antiplatelet effects were shown to improve thromboresistance of the AG/HMDI/NORel polymer-coated ECCs and move

Obreros agrícolas migrantes en Sinaloa

OpenAIRE

Florencio Posadas Segura

2015-01-01

El objetivo de este artículo es demostrar la presencia significativa de los obreros agrícolas migrantes, algunas características que la explican y la pauperización que experimentan. La causa principal de la migración es la desocupación; los empresarios controlan los métodos de contratación, trasportación y explotación, y los jornaleros rurales migrantes trabajan más, ganan menos y su situación es mayormente miserable. Esto se ilustra con el caso de Villa Benito Juárez, Sinaloa, que prueba la ...

Metodología para evaluar el impacto de la maquinaria agrícola sobre los recursos naturales del medio ambiente

Directory of Open Access Journals (Sweden)

Norge Díaz Rodríguez

2007-01-01

Full Text Available Se realizó una propuesta de metodología para evaluar el impacto que ejerce la maquinaria agrícola sobre algunos de los recursos naturales del medio ambiente. Durante su explotación la maquinaria agrícola, como unidad energética para el trabajo agrícola, produce un conjunto de impactos negativos sobre el medio en tres direcciones fundamentales: suelo, aire, y agua. A pesar de existir conciencia sobre este problema, no se disponen de herramientas apropiadas para hacer una evaluación certera de la magnitud de estos impactos, lo cual no es una simple tarea.

40 CFR 74.20 - Data for baseline and alternative baseline.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Data for baseline and alternative baseline. 74.20 Section 74.20 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... baseline and alternative baseline. (a) Acceptable data. (1) The designated representative of a combustion...

Trabajadores agrícolas migrantes en Baja California. Vinculación con la migración internacional

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Ma. Eugenia Anguiano Téllez

1989-09-01

Full Text Available En este ensayo los jornaleros agrícolas migrantes son clasificados en dos estratos: el primero, considera la migración internacional, es decir, aquéllos que se internan en Estados Unidos con el propósito de conseguir empleo; y el segundo, corresponde a la migración interna de los trabajadores agrícolas que permanecen en Baja California para laborar en los valles de Mexicali y San Quintín.En este trabajo se señalan las diferencias entre estos dos estratos, tanto de carácter económico como en los niveles de educación; asimismo, se comparan las características de los jornaleros agrícolas migrantes que cruzan a Estados Unidos por Mexicali y por Tijuana, según su actividad económica de procedencia y su expectativa de empleo en los Estados Unidos.

Strand Burner Results of AFP-001 Propellant with Inert Coating for Temperature Compensation

Science.gov (United States)

2015-10-01

there were 4 different configurations: baseline, a C-100 coated, an SC-11 coated, and a urethane acrylate (UA) coated. C-100 is a polyurea based...coating, SC-11 is an epoxy-based coating, and UA is a urethane- acrylate -based coating. These coatings were chosen to target a specific strength...Ignition was achieved by running current through a nichrome wire placed on top of the sample. Events were recorded with a Phantom high-speed camera

Solo agrícola e agricultura em espaço urbano: dinâmicas. O exemplo de Évora

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Maria Freire

2014-12-01

Full Text Available O objetivo do artigo é melhorar o entendimento sobre o significado da componente agrícola em espaço urbano para as sociedades e perspetivar estratégias no sentido de promover o património solo agrícola e a permanência e sustentabilidade do uso agrícola em espaço urbano. A metodologia de trabalho seguida compreende a análise da dinâmica de evolução urbana, associada à presença da agricultura em espaço urbano em Évora, numa perspetiva que inclui o seu significado nos domínios históricos, sociais, económicos, ecológicos e estéticos.

Analysis of Gln223Agr Polymorphism of Leptin Receptor Gene in Type II Diabetic Mellitus Subjects among Malaysians

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Chong Pei Pei

2013-09-01

Full Text Available Leptin is known as the adipose peptide hormone. It plays an important role in the regulation of body fat and inhibits food intake by its action. Moreover, it is believed that leptin level deductions might be the cause of obesity and may play an important role in the development of Type 2 Diabetes Mellitus (T2DM, as well as in cardiovascular diseases (CVD. The Leptin Receptor (LEPR gene and its polymorphisms have not been extensively studied in relation to the T2DM and its complications in various populations. In this study, we have determined the association of Gln223Agr loci of LEPR gene in three ethnic groups of Malaysia, namely: Malays, Chinese and Indians. A total of 284 T2DM subjects and 281 healthy individuals were recruited based on International Diabetes Federation (IDF criteria. Genomic DNA was extracted from the buccal specimens of the subjects. The commercial polymerase chain reaction (PCR method was carried out by proper restriction enzyme MSP I to both amplify and digest the Gln223Agr polymorphism. The p-value among the three studied races was 0.057, 0.011 and 0.095, respectively. The values such as age, WHR, FPG, HbA1C, LDL, HDL, Chol and Family History were significantly different among the subjects with Gln223Agr polymorphism of LEPR (p < 0.05.

Analysis of Gln223Agr polymorphism of Leptin Receptor Gene in type II diabetic mellitus subjects among Malaysians.

Science.gov (United States)

Etemad, Ali; Ramachandran, Vasudevan; Pishva, Seyyed Reza; Heidari, Farzad; Aziz, Ahmad Fazli Abdul; Yusof, Ahmad Khairuddin Mohamed; Pei, Chong Pei; Ismail, Patimah

2013-09-18

Leptin is known as the adipose peptide hormone. It plays an important role in the regulation of body fat and inhibits food intake by its action. Moreover, it is believed that leptin level deductions might be the cause of obesity and may play an important role in the development of Type 2 Diabetes Mellitus (T2DM), as well as in cardiovascular diseases (CVD). The Leptin Receptor (LEPR) gene and its polymorphisms have not been extensively studied in relation to the T2DM and its complications in various populations. In this study, we have determined the association of Gln223Agr loci of LEPR gene in three ethnic groups of Malaysia, namely: Malays, Chinese and Indians. A total of 284 T2DM subjects and 281 healthy individuals were recruited based on International Diabetes Federation (IDF) criteria. Genomic DNA was extracted from the buccal specimens of the subjects. The commercial polymerase chain reaction (PCR) method was carried out by proper restriction enzyme MSP I to both amplify and digest the Gln223Agr polymorphism. The p-value among the three studied races was 0.057, 0.011 and 0.095, respectively. The values such as age, WHR, FPG, HbA1C, LDL, HDL, Chol and Family History were significantly different among the subjects with Gln223Agr polymorphism of LEPR (p < 0.05).

Cambio climático, ensalitramiento de suelos y producción agrícola en áreas de riego

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Leonardo Pulido Madrigal

2016-04-01

Full Text Available Se analizó el impacto del clima en los problemas de salinidad, drenaje y producción agrícola en el Distrito de Riego 038 río Mayo Sonora el cual presenta afectaciones por sales en 32% de su superficie. Con datos de clima y agronómicos generados entre 1970-2001, se elaboraron modelos de regresión lineal simple para estudiar la relación entre la superficie ensalitrada con la temperatura ambiente, superficie afectada por niveles freáticos superficiales, volumen de riego, salinidad del agua de riego, precipitación pluvial, producción agrícola y productividad del agua. Asimismo, se correlacionó el manto freático con la temperatura, volumen de riego y precipitación pluvial. La producción se correlacionó con la salinidad del suelo, temperatura ambiente, superficie afectada por niveles freáticos superficiales y volumen de riego. Además, por medio de modelos de regresión lineal múltiple se determinaron las relaciones tanto de la superficie ensalitrada como de la producción agrícola, con la temperatura, superficie afectada por niveles freáticos superficiales, volumen de riego, superficie cosechada y precipitación pluvial. Los resultados evidenciaron que el aumento de superficie ensalitrada está relacionado con el incremento de temperatura; mismo que se asoció con la disminución del volumen de cosechas y con el aumento de superficie con niveles freáticos. Se encontró que los volúmenes de riego impactan en el incremento de la superficie agrícola con niveles freáticos someros y con el aumento de superficie ensalitrada. Con el calentamiento global los problemas de salinidad del suelo se incrementaron entre 24.1 y 15.8% en los estratos de suelo a 30 y 60 cm de profundidad, respectivamente. Asimismo, se estimó un crecimiento del 21.9% de superficies con niveles freáticos superficiales. El impacto del calentamiento global en el volumen de producción agrícola se estimó en una reducción del 18.9% del volumen de cosechas.

El Banco Nacional de Fomento en el desarrollo del sector agrícola durante el quinquenio 1992-1996. Propuesta a mediano plazo.

OpenAIRE

Proaño Gaibor, Alfonso

1998-01-01

El estudio contiene un panorama de la economía y del sector agrícola nacional, las políticas económicas aplicadas en el período de estudio, sus indicadores macroeconómicos, el PIB, el tipo de cambio y la incidencia de la agricultura en la población económicamente activa. El sector agrícola es analizado desde la perspectiva del comercio exterior, evaluando importaciones y exportaciones del sector agrícola, resultados en balanza comercial y proyección en el mercado global. La agricultura en...

Sol-gel optical coatings for lasers: Part 1

International Nuclear Information System (INIS)

Floch, H.G.; Belleville, P.F.; Priotton, J.J.

1995-01-01

Many manufacturers and users claim that optical coatings are best prepared by physical vapor deposition technology. Others believe that sol-gel technology is an effective and competitive alternative. This article, the first of three, emphasizes sol-gel thin-film history and relates it to high-power laser technology, chemistry of the sol-gel process, production of optical coatings and deposition techniques. The second and third articles describe the preparation and performance of antireflective and highly reflective sol-gel optical coatings, respectively, that have been developed for the 1.8-MJ/500-TW (351-nm) pulsed neodymium-glass laser. This powerful laser is to be used in France's Inertial Confinement Fusion (ICF) program. It will demonstrate, at the laboratory scale, ignition of deuterium-tritium fusion fuel

Eielson Air Force Base OU-1 baseline risk assessment

International Nuclear Information System (INIS)

Jarvis, M.T.; Jarvis, T.T.; Van Houten, N.C.; Lewis, R.E.

1993-09-01

This Baseline Risk Assessment report is the second volume in a set of three volumes for operable Unit 1 (OU-1). The companion documents contain the Remedial Investigation and the Feasibility Study. Operable Unit 1 (OU-1) is one of several groups of hazardous waste sites located at Eielson Air Force Base (AFB) near Fairbanks, Alaska. The operable units at Eielson are typically characterized by petroleum, oil, lubricant/solvent contamination, and by the presence of organics floating at the water table. In 1989 and 1990, firms under contract to the Air Force conducted field studies to gather information about the extent of chemical contamination in soil, groundwater, and soil air pore space (soil gas) at the site. This report documents the results of a baseline risk assessment, which uses the 1989 and 1991 site characterization database to quantify the potential human health risk associated with past Base industrial activities in the vicinity of OU-1. Background data collected in 1992 were also used in the preparation of this report

HIV-1 Nef hijacks clathrin coats by stabilizing AP-1:Arf1 polygons.

Science.gov (United States)

Shen, Qing-Tao; Ren, Xuefeng; Zhang, Rui; Lee, Il-Hyung; Hurley, James H

2015-10-23

The lentiviruses HIV and simian immunodeficiency virus (SIV) subvert intracellular membrane traffic as part of their replication cycle. The lentiviral Nef protein helps viruses evade innate and adaptive immune defenses by hijacking the adaptor protein 1 (AP-1) and AP-2 clathrin adaptors. We found that HIV-1 Nef and the guanosine triphosphatase Arf1 induced trimerization and activation of AP-1. Here we report the cryo-electron microscopy structures of the Nef- and Arf1-bound AP-1 trimer in the active and inactive states. A central nucleus of three Arf1 molecules organizes the trimers. We combined the open trimer with a known dimer structure and thus predicted a hexagonal assembly with inner and outer faces that bind the membranes and clathrin, respectively. Hexagons were directly visualized and the model validated by reconstituting clathrin cage assembly. Arf1 and Nef thus play interconnected roles in allosteric activation, cargo recruitment, and coat assembly, revealing an unexpectedly intricate organization of the inner AP-1 layer of the clathrin coat. Copyright © 2015, American Association for the Advancement of Science.

Influence of graphene coating on the adsorption and tribology of Xe on Au(1 1 1) substrate.

Science.gov (United States)

Zhang, Y N; Bortolani, V; Mistura, G

2014-11-05

The adsorption and tribological properties of graphene have received increasing attention for the further development of graphene-based coatings in applications. In this work, we performed first principles calculations with the inclusion of the nonlocal van der Waals correction to study the effect of graphene coating on the adsorption geometries, sliding frictions and electronic properties of Xe monolayer on the Au(1 1 1) substrate. The calculated activation energies indicate that Xe becomes movable on pure Au(1 1 1) surface at a temperature of around 30 K, whereas its motion can be activated only at a high temperature of ~50 K on graphene and on graphene-coated Au(1 1 1) substrates, in good agreement with recent experimental measurements by quartz crystal microbalance technique.

Accessory Gene Regulator-1 Locus Is Essential for Virulence and Pathogenesis of Clostridium difficile

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Charles Darkoh

2016-08-01

Full Text Available Clostridium difficile infection (CDI is responsible for most of the definable cases of antibiotic- and hospital-associated diarrhea worldwide and is a frequent cause of morbidity and mortality in older patients. C. difficile, a multidrug-resistant anaerobic pathogen, causes disease by producing toxins A and B, which are controlled by an accessory gene regulator (Agr quorum signaling system. Some C. difficile strains encode two Agr loci in their genomes, designated agr1 and agr2. The agr1 locus is present in all of the C. difficile strains sequenced to date, whereas the agr2 locus is present in a few strains. The functional roles of agr1 and agr2 in C. difficile toxin regulation and pathogenesis were unknown until now. Using allelic exchange, we deleted components of both agr loci and examined the mutants for toxin production and virulence. The results showed that the agr1 mutant cannot produce toxins A and B; toxin production can be restored by complementation with wild-type agr1. Furthermore, the agr1 mutant is able to colonize but unable to cause disease in a murine CDI model. These findings have profound implications for CDI treatment because we have uncovered a promising therapeutic target for the development of nonantibiotic drugs to treat this life-threatening emerging pathogen by targeting the toxins directly responsible for disease.

Aluminium-rich coatings as tritium permeation barriers on MANET (1.4914) stainless steel

International Nuclear Information System (INIS)

Terlain, A.; De Vito, E.

1994-01-01

Al-rich coatings on 1.4914 martensitic steel, produced by different techniques, have been investigated with optical and scanning electron microscopy, X-ray fluorescence and X-ray photoelectron spectroscopy. Tests for their Pb-17Li compatibility and thermo cycling behaviours have been performed on some coated specimens. Up to now, none of the investigated coatings can be eliminated on the basis of the tests and analyses performed. Further work is required to adapt 1.4914 steel coating techniques to fusion reactor requirements. (author) 9 refs.; 5 figs.; 1 tab

Commissioning methods applied to the Hunterston 'B' AGR operator training simulator

International Nuclear Information System (INIS)

Hacking, D.

1985-01-01

The Hunterston 'B' full scope AGR Simulator, built for the South of Scotland Electricity Board by Marconi Instruments, encompasses all systems under direct and indirect control of the Hunterston central control room operators. The resulting breadth and depth of simulation together with the specification for the real time implementation of a large number of highly interactive detailed plant models leads to the classic problem of identifying acceptance and acceptability criteria. For example, whilst the ultimate criterion for acceptability must clearly be that within the context of the training requirement the simulator should be indistinguishable from the actual plant, far more measurable (i.e. less subjective) statements are required if a formal contractual acceptance condition is to be achieved. Within the framework, individual models and processes can have radically different acceptance requirements which therefore reflect on the commissioning approach applied. This paper discusses the application of a combination of quality assurance methods, design code results, plant data, theoretical analysis and operator 'feel' in the commissioning of the Hunterston 'B' AGR Operator Training Simulator. (author)

Existe convergência espacial da produtividade agrícola no Brasil?

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Eduardo Simões de Almeida

2008-03-01

Full Text Available Este trabalho analisa a convergência espacial da produtividade agrícola da terra para as microrregiões brasileiras entre o período de 1991 a 2003. Tal análise avalia se há evidências para a existência de convergência beta da produtividade agrícola, controlando-se explicitamente para efeitos espaciais. Para tanto, conduziu-se preliminarmente uma análise exploratória de dados espaciais, que detectou a presença de autocorrelação espacial para a produtividade da terra. Numa etapa posterior, desenvolveram-se modelos econométricos espaciais para a análise da convergência.This work analyzes the convergence of land productivity for Brazilian regions from 1991 to 2003. It evaluates if there is or not beta convergence of the agricultural productivity, controlling explicitly for spatial effects. To do so, an exploratory spatial data analysis was previously implemented and the presence of spatial autocorrelation for the land productivity was detected. In addition, spatial econometric models were developed for the convergence analysis.

TaxHf1−xB2–SiC multiphase oxidation protective coating for SiC-coated carbon/carbon composites

International Nuclear Information System (INIS)

Ren, Xuanru; Li, Hejun; Fu, Qiangang; Li, Kezhi

2014-01-01

Highlights: • Ta x Hf 1−x B 2 –SiC coating was prepared on SiC coated C/C by in-situ reaction method. • TaB 2 and HfB 2 were introduced in the form of solid solution Ta x Hf 1−x B 2 . • The coating could protect C/C for 1480 h with only 0.57% mass loss at 1773 K in air. • Oxidation layer consists of out Ta–Si–O compound layer and inner SiO 2 glass layer. • Ta–Si–O compound silicate layer presents a better stability than SiO 2 glass layer. - Abstract: A Ta x Hf 1−x B 2 –SiC coating was prepared by in-situ reaction method on SiC coated C/C composites. Ta x Hf 1−x B 2 phase is the form of solid solution between TaB 2 and HfB 2 . Isothermal oxidation behavior at 1773 K and ablation behavior of the coated C/C were tested. Ta x Hf 1−x B 2 –SiC/SiC coating could protect the C/C from oxidation at 1773 K for 1480 h and ablation above 2200 K for 40 s. During oxidation, oxides of Ta and Hf atoms exist as “pinning phases” in the compound glass layer consisted of outer Ta–Si–O compound silicate layer and inner SiO 2 glass layer, which was responsible for the excellent oxidation resistance

Opposing Roles of the Staphylococcus aureus Virulence Regulators, Agr and Sar, in Triton X-100- and Penicillin-Induced Autolysis

OpenAIRE

Fujimoto, David F.; Bayles, Kenneth W.

1998-01-01

The regulation of murein hydrolases is a critical aspect of peptidoglycan growth and metabolism. In the present study, we demonstrate that mutations within the Staphylococcus aureus virulence factor regulatory genes, agr and sar, affect autolysis, resulting in decreased and increased autolysis rates, respectively. Zymographic analyses of these mutant strains suggest that agr and sar exert their effects on autolysis, in part, by modulating murein hydrolase expression and/or activity.

Elevated electrochemical performance of (NH4)3AlF6-coated 0.5Li2MnO3·0.5LiNi1/3Co1/3Mn1/3O2 cathode material via a novel wet coating method

International Nuclear Information System (INIS)

Xu, Guofeng; Li, Jianling; Xue, Qingrui; Dai, Yu; Zhou, Hongwei; Wang, Xindong; Kang, Feiyu

2014-01-01

A novel wet method of (NH 4 ) 3 AlF 6 coating was explored to enhance the electrochemical performance of Mn-based solid-solution cathode material 0.5Li 2 MnO 3 ·0.5LiNi 1/3 Co 1/3 Mn 1/3 O 2 . The X-ray powder diffraction patterns show that the coating material is pure-phase (NH 4 ) 3 AlF 6 and both pristine and coated samples can be indexed to hexagonal α-NaFeO 2 layered structure with space group of R-3 m. The field-emission scanning electron microscope images and the energy dispersive X-ray spectroscopy show that (NH 4 ) 3 AlF 6 is successfully coated on the surface of active particle. The (NH 4 ) 3 AlF 6 coated electrodes exhibit improved electrochemical performance, for instance, the initial charge-discharge efficiency was promoted by 5% (NH 4 ) 3 AlF 6 coating, the 1 wt.% and 3 wt.% coated electrodes deliver elevated cycling ability which is ascribed to the lower resistance between electrode and electrolyte as indicated by AC impedance measurement at different cycles. In addition, the coated-electrodes also give enhanced rate capability particularly for 1 wt.% NAF-coated electrode performing surprising capacity of 143.4 mAh g −1 at 5 C higher than that of 109.4 mAh g −1 for pristine electrode. Furthermore, the 1 wt.% NAF-coated electrode also shows improved cycle and rate performance at 55°C

Metodologías para establecer valores de referencia de metales pesados en suelos agrícolas: Perspectivas para Colombia

Directory of Open Access Journals (Sweden)

Rueda Saa Germán

2011-09-01

Full Text Available

Los problemas ambientales de los metales pesados en los suelos están relacionados con su carácter tóxico cuando se acumulan o cuando interactüan con algunas propiedades especificas, se movilizan a  través del perfil a la cadena trófica mediante los cuerpos de agua o los cultivos y pueden llegar a afectar la salud humana. En países desarrollados el establecimiento de valores de referencia de estos metales ha permitido el mejoramiento de la planeación y la gestión ambiental del recurso suelo, y se ha convertido en un instrumento de control para las entidades ambientales que ha permitido evaluar el impacto en diferentes actividades agrícolas.

En este artículo se analizan diferentes conceptos relacionados con los niveles de metales pesados en suelos agrícolas y la incidencia de las características edafológicas en su concentración. Se revisan, igualmente, algunas metodologias para derivar valores de referencia especificos aplicables a suelos agrícolas colombianos, y se plantean algunas perspectivas orientadas a la protección y recuperación de suelos en el país. En Colombia en la actualidad no se cuenta con criterios y estándares de calidad para metales pesados en suelos agrícolas; por esto se hace necesario gestionar el apoyo de entidades gubernamentales con el fin de iniciar y desarrollar investigaciones en diferentes sectores agricolas primarios, contribuyendo de esta forma a garantizar la producción agrícola y la sostenibilidad ambiental del recurso suelo.

Thermally joining and/or coating or thermally separating the workpieces having heat-sensitive coating, comprises restoring coating by thermally coating the coating material after thermally joining and/or coating or thermally separating

OpenAIRE

Riedel, Frank; Winkelmann, Ralf; Puschmann, Markus

2011-01-01

The method for thermally joining and/or coating or thermally separating the workpieces (1), which have a heat-sensitive coating (2), comprises restoring the coating by thermally coating a coating material (3) after thermally joining and/or coating or thermally separating the workpieces. A part of the thermal energy introduced in the workpiece for joining and/or coating or separating or in the workpieces is used for thermally coating the coating material. Two workpieces are welded or soldered ...

Rehabilitación de un suelo salino con yeso agrícola en un cultivo de nogal en el Valle del Yaqui

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Alma Trasviña Barriga

2018-01-01

Full Text Available El cultivo de nogal es una actividad en amplio crecimiento en el Valle del Yaqui, Sonora. Las zonas nogaleras de la región se caracterizan por presentar problemas de salinidad y altas concentraciones de sodio intercambiable, lo que provoca disminución en la productividad de la nuez pecana. Al terminar la temporada de riego con agua del sistema de presas del Río Yaqui, el uso de agua de pozos profundos es utilizada, generalmente en los meses de mayo a agosto. Esto puede ocasionar acumulación de sales en el suelo cuando el agua es de mala calidad. El yeso agrícola ha sido utilizado como enmienda para rehabilitar el suelo mejorando las propiedades químicas del mismo. El objetivo del presente estudio fue determinar el efecto de la aplicación de yeso agrícola en un suelo salino de un huerto de nogal en el Valle del Yaqui. Se llevó a cabo la rehabilitación durante dos años, en el primer año se emplearon dosis de 5 y 10 Mg ha-1, mientras que en el segundo año 2 Mg ha-1 de yeso agrícola. Se realizaron dos lavados por melgas después de cada aplicación. Los análisis químicos del suelo se ejecutaron de acuerdo a la NOM-021-RECNAT-2000 durante tres años, previo y posterior a las aplicaciones de enmienda. Posterior a la aplicación de enmienda, disminuyeron los valores de conductividad eléctrica de 12.41 a 6.29 dS m-1, porcentaje de sodio intercambiable de 12.48 a 5.57 y relación de adsorción de sodio de 10.54 a 4.88 en la profundidad de 0-30 cm en la primera aplicación. El empleo de yeso agrícola y los lavados en el suelo salino del huerto de nogal mejoraron las propiedades químicas.

Molecular interactions of mussel protective coating protein, mcfp-1, from Mytilus californianus.

Science.gov (United States)

Lu, Qingye; Hwang, Dong Soo; Liu, Yang; Zeng, Hongbo

2012-02-01

Protective coating of the byssus of mussels (Mytilus sp.) has been suggested as a new paradigm of medical coating due to its high extensibility and hardness co-existence without their mutual detriment. The only known biomacromolecule in the extensible and tough coating on the byssus is mussel foot protein-1 (mfp-1), which is made up with positively charged residues (~20 mol%) and lack of negatively charged residues. Here, adhesion and molecular interaction mechanisms of Mytilus californianus foot protein-1 (mcfp-1) from California blue mussel were investigated using a surface forces apparatus (SFA) in buffer solutions of different ionic concentrations (0.2-0.7 M) and pHs (3.0-5.5). Strong and reversible cohesion between opposed positively charged mcfp-1 films was measured in 0.1 M sodium acetate buffer with 0.1 M KNO(3). Cohesion of mcfp-1 was gradually reduced with increasing the ionic strength, but was not changed with pH variations. Oxidation of 3,4-dihydroxyphenylalanine (DOPA) residues of mcfp-1, a key residue for adhesive and coating proteins of mussel, didn't change the cohesion strength of mcfp-1 films, but the addition of chemicals with aromatic groups (i.e., aspirin and 4-methylcatechol) increased the cohesion. These results suggest that the cohesion of mcfp-1 films is mainly mediated by cation-π interactions between the positively charged residues and benzene rings of DOPA and other aromatic amino acids (~20 mol% of total amino acids of mcfp-1), and π-π interactions between the phenyl groups in mcfp-1. The adhesion mechanism obtained for the mcfp-1 proteins provides important insight into the design and development of functional biomaterials and coatings mimicking the extensible and robust mussel cuticle coating. Copyright © 2011 Elsevier Ltd. All rights reserved.

Dispersion stability of 1-octanethiol coated Cu nanoparticles in a 1-octanol solvent for the application of nanoink

Energy Technology Data Exchange (ETDEWEB)

Cho, Danee [Department of Materials Engineering, Hanyang University, Ansan 426-791 (Korea, Republic of); Baik, Jong-Hwan [Lean on Tech., Guri 471-854 (Korea, Republic of); Choi, Da-hyun [Department of Materials Engineering, Hanyang University, Ansan 426-791 (Korea, Republic of); Lee, Caroline Sunyong, E-mail: sunyonglee@hanyang.ac.kr [Department of Materials Engineering, Hanyang University, Ansan 426-791 (Korea, Republic of)

2014-08-01

Conductive ink with Copper nanoparticles (Cu NPs) has various advantages compared with conventional ink, such as good electrical conductivity and low cost. However, it suffers through easily oxidization problem, leading to an unstable electrical conductivity, which decreases over time. Therefore, it is important to prevent (or least minimize) oxidation of the Cu NPs. In this study, Cu NPs with diameter of 50 nm were coated with 1-octanethiol (CH₃(CH₂)₇SH) in a high-vacuum condition (5.33 × 10⁻⁴ Pa). The coating conditions were systematically varied to investigate the effect on the coating thicknesses. Coated Cu NPs were dispersed in 1-octanol to form the conductive ink, and the dispersion behavior was studied as a function of the thickness of the 1-octanethiol coating. The thickness of the coating layer was characterized using transmission electron microscopy and X-ray spectroscopy analysis, and was found to be 3 nm, 6 nm, and 10 nm. The dispersion stability of the inks was characterized by Turbiscan dispersion stability and viscosity measurements, and it was found that the copper nanoink formed using Cu NPs with a 6-nm-thick coating exhibited the most stable dispersion properties.

Dispersion stability of 1-octanethiol coated Cu nanoparticles in a 1-octanol solvent for the application of nanoink

International Nuclear Information System (INIS)

Cho, Danee; Baik, Jong-Hwan; Choi, Da-hyun; Lee, Caroline Sunyong

2014-01-01

Conductive ink with Copper nanoparticles (Cu NPs) has various advantages compared with conventional ink, such as good electrical conductivity and low cost. However, it suffers through easily oxidization problem, leading to an unstable electrical conductivity, which decreases over time. Therefore, it is important to prevent (or least minimize) oxidation of the Cu NPs. In this study, Cu NPs with diameter of 50 nm were coated with 1-octanethiol (CH 3 (CH 2 ) 7 SH) in a high-vacuum condition (5.33 × 10 −4 Pa). The coating conditions were systematically varied to investigate the effect on the coating thicknesses. Coated Cu NPs were dispersed in 1-octanol to form the conductive ink, and the dispersion behavior was studied as a function of the thickness of the 1-octanethiol coating. The thickness of the coating layer was characterized using transmission electron microscopy and X-ray spectroscopy analysis, and was found to be 3 nm, 6 nm, and 10 nm. The dispersion stability of the inks was characterized by Turbiscan dispersion stability and viscosity measurements, and it was found that the copper nanoink formed using Cu NPs with a 6-nm-thick coating exhibited the most stable dispersion properties.

Estudio de los métodos para la evaluación de los proveedores para una empresa de fabricación de maquinaria agrícola

OpenAIRE

Vilalta Martí, Josep M.

2012-01-01

El objeto de este proyecto es el estudio de los métodos para la evaluación de los proveedores para una empresa de fabricación de maquinaria agrícola y la implantación de la misma. Concretamente maquinaria agrícola pesada destinada al transporte de productos agrícolas. Dicha fábrica estará situada en la provincia de Lérida.

Potencial de biodegradación de DDT y sus metabolitos en suelos agrícolas de Chinandega

Directory of Open Access Journals (Sweden)

Carlos E. Noguera Solís

2008-04-01

Full Text Available LA PRESENTE INVESTIGACIÓN EVALUÓ EL POTENCIAL DE BIODEGRADACIÓN DEL 1,1,1-Tricloro- 2,2-bis(4-clorofeniletano (DDT y sus metabolitos en suelos agrícolas pertenecientes a fincas del municipio de El Viejo, Chinandega, a través de dos ensayos: ensayo de biodegradación ex situ y ensayo de búsqueda e identificación de microorganismos capaces de biodegradar DDT. En el primer ensayo se determinó el porcentajede biodegradación, bajo condiciones idóneas, durante un período de 100 días en diferentes lotes de suelo con diferentes aditivos (cachaza y estiércol a través de la aplicación de cepas microbianas comerciales Environoc 201®. De ello se obtuvo como resultado un porcentaje de biodegradación mayor para el lote que no presentaba aditivos orgánicos, siendo éste de 23,92%. En el ensayo de búsqueda eidentificación de bacterias se lograron aislar e identificar cepas microbianas nativas de los suelos agrícolas objeto de estudio utilizando medios de cultivo con DDT como única fuente de carbono y energía. Como resultado se lograron identificar los siguientes microorganismos: Pseudomonas sp., Streptomyces sp., Phanerochaetechrysosporium y levaduras.

Necesidades educacionales sobre riesgo de plaguicidas en el contexto socio-ambiental de las comunidades agrícolas de Sonora

Directory of Open Access Journals (Sweden)

M.I. Silveira Gramont

2016-01-01

Full Text Available Para proponer estrategias de educación y comunicación sobre plaguicidas en las comunidades agrícolas de Sonora, se requiere situar la problemática de la exposición a plaguicidas en el contexto socio-cultural y ambiental de las comunidades afectadas, tomando en cuenta los factores que contribuyen al mayor riesgo de exposición de los trabajadores agrícolas y de sus familias. Este estudio examina los factores poblacionales, educacionales, culturales y de trabajo de habitantes y trabajadores agrícolas de dichas comunidades, así como las limitaciones de infraestructura comunitaria y de condiciones de vivienda en relación al riesgo de contaminación por plaguicidas. Sobre la base de este análisis se proponen posibles alternativas educacionales orientadas a mitigar tal riesgo en el contexto socio-cultural de dichas comunidades. Método De los estudios reportados sobre la presencia de residuos de plaguicidas en productos agrícolas y acuícolas, en suelos, agua, medio ambiente y en líquidos corporales de niños y adultos de Sonora, se puede concluir que tanto los trabajadores agrícolas como la población que reside cerca de las zonas agrícolas, están sujetos a un mayor riesgo de contaminación por plaguicidas. Para la realización del presente estudio se seleccionaron cinco comunidades localizadas en los valles agrícolas más productivos de Sonora, en las cuales se han llevado a cabo investigaciones relacionadas con plaguicidas. Básicamente, se analizó la información obtenida de encuestas aplicadas a residentes y trabajadores agrícolas de dichas comunidades, para explorar su conocimiento sobre uso y manejo de plaguicidas, percepción del riesgo que tales sustancias representan y las prácticas de protección personal que llevan a cabo para la prevención de dichos riesgos (en el hogar y trabajo. También se describe la infraestructura de los poblados y las viviendas de sus habitantes en relación al potencial de riesgo de contaminaci

Cu{sub 1.5}Mn{sub 1.5}O{sub 4}-based ceramic spectrally selective coatings for efficient solar absorber applications

Energy Technology Data Exchange (ETDEWEB)

Ma, Pengjun [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China); University of Chinese Academy of Sciences, Beijing, 100049 (China); Geng, Qingfen; Gao, Xianghu [Research & Development Center for Eco-material and Eco-chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China); Yang, Shengrong [State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China); Liu, Gang, E-mail: gangliu@licp.cas.cn [Research & Development Center for Eco-material and Eco-chemistry, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou, 730000 (China)

2016-08-05

Cu{sub 1.5}Mn{sub 1.5}O{sub 4}-based ceramic spectrally selective (CSS) coating was deposited on aluminum substrate using a sol–gel dip-coating method. The citric acid introduced in the precursor system lowered the required calcining temperature of crystalline Cu{sub 1.5}Mn{sub 1.5}O{sub 4}. X-Ray diffraction (XRD) peaks of coatings annealed above 450 °C were found to coincide exactly with that of crystalline Cu{sub 1.5}Mn{sub 1.5}O{sub 4} in JCPDS database. By optimizing the withdrawal rate and calcining temperature, coating with spectral selectivity as good as α{sub s} = 0.876 and ε{sub 100} = 0.057 was achieved after only one dipping/annealing cycle. Subjected to an accelerated ageing test at 259 °C, the obtained CSS coating showed an excellent thermally durability with the performance criterion (PC) values below 0.05. - Highlights: • Cu{sub 1.5}Mn{sub 1.5}O{sub 4}-based CSS coating is achieved after only one dipping/annealing cycle. • Cu{sub 1.5}Mn{sub 1.5}O{sub 4} coating is obtained as the annealing temperature reaches to 450 °C. • Cu{sub 1.5}Mn{sub 1.5}O{sub 4} coating exhibits optical parameter: α{sub s} = 0.876 and ε{sub 100} = 0.057. • Cu{sub 1.5}Mn{sub 1.5}O{sub 4} coating shows the excellent stability in low to mid temperature region.

Planificación estratégica de un sistema provincial de extensión agrícola (Sipea) para la Provincia de Acobamba

OpenAIRE

Yzarra Aguilar, Adelfa

2017-01-01

El objetivo fue analizar la realidad actual del servicio de extensión agrícola en la provincia de Acobamba, región Huancavelica, para proponer uno que articule los componentes hacia una óptima calidad del servicio, realizando los análisis de carácter externo positivo o negativo que favorece o perjudica el desarrollo del servicio de extensión agrícola. Se diseñó un plan estratégico para el sistema provincial de extensión agrícola para Acobamba, el enlace de los objetivos con la realidad actual...

Metodologías para establecer valores de referencia de metales pesados en suelos agrícolas: perspectivas para Colombia

Directory of Open Access Journals (Sweden)

Germán Rueda Saa

2011-07-01

Full Text Available Los impactos ambientales de los metales pesados en los suelos están relacionados con su carácter tóxico cuando se acumulan o interactúan con algunas propiedades específicas, se movilizan a través del perfil a la cadena trófica mediante los cuerpos de agua o los cultivos y pueden llegar a afectar la salud humana. En países desarrollados el establecimiento de valores de referencia de estos metales ha permitido el mejoramiento de la planeación y la gestión ambiental del recurso suelo, y se ha convertido en un instrumento de control para las entidades ambientales que ha permitido evaluar el impacto en diferentes actividades agrícolas. En este artículo se analizan diversos conceptos relacionados con los niveles de metales pesados en suelos agrícolas y la incidencia de las características edafológicas en su concentración. Se revisan, igualmente, algunas metodologías para derivar valores de referencia específicos aplicables a suelos agrícolas colombianos, y se plantean algunas perspectivas orientadas a la protección y recuperación de suelos en el país. En Colombia en la actualidad no se cuenta con criterios y estándares de calidad para medir la contaminación por metales pesados en suelos agrícolas; por esto se hace necesario gestionar el apoyo de entidades gubernamentales con el fin de iniciar y desarrollar investigaciones en diferentes sectores agrícolas primarios, contribuyendo de esta forma a garantizar una producción más limpia y la sostenibilidad ambiental del recurso suelo.

The wide range in-core neutron measurement system used in the Windscale AGR concluding experiments

International Nuclear Information System (INIS)

Goodings, A.; Budd, J.; Wilson, I.

1982-06-01

The Windscale AGR concluding experiments included a comparison of theoretical and experimental power transients and required measurements of neutron flux as a function of position and time within the reactor core. These measurements were specified to cover a working range as wide as possible and had to be made against the in-core gamma background of up to 4 x 10 7 R(hr) - 1 . The detectors were required to operate in special channels cooled by reactor inlet CO 2 and the overall system needed a response time such that it could follow transients with doubling times down to 2s with an accuracy of 2 or 3%. These problems were solved by the use of gas ion fission chambers operating in the current fluctuation or ''Campbelling'' mode. Their neutron to gamma sensitivity ratio was optimised by the use of unusually low filling pressures and they were fitted with special ''trilaminax'' mineral insulated cables to minimise the effects of electrical interference at the 100 kHz channel centre frequency. Ten detectors were built and nine were installed in the reactor, three in each of three special stringers at different radial positions. All were processed and tested for operation at 350 deg. C and their fissile coatings (430 μg cm - 1 of natural uranium) were matched to give individual neutron sensitivities with a population spread better than +- 6% about the mean. The mean absolute sensitivities were determined to about +- 5% against manganese foils in the NESTOR reactor at AEE Winfrith. The detectors were complemented by special signal processing channels which provided current fluctuation sensitivity and appropriate output signals to the experiment data acquisition system. These channels also permitted dc measurement of chamber current for more precise flux determination near reactor full power

Manufacture of steam generator units and components for the AGR power stations at Heysham II and Torness

International Nuclear Information System (INIS)

Glasgow, J.R.; Parkin, K.

1984-01-01

The current AGR Steam Generator is a development of the successful once-through units supplied for the Oldbury Magnox and Hinkley B/Hunterston B AGR power stations. In this paper a brief outline of the evolution of the steam generator design from the earlier gas cooled reactor stations is presented. A description of the main items of fabrication development is given. The production facilities for the manufacture of the units are described. Reference is also made to some of the work on associated components. The early experience on the construction site of installation of the steam generators is briefly outlined. (author)

Manufacture of steam generator units and components for the AGR power stations at Heysham II and Torness

Energy Technology Data Exchange (ETDEWEB)

Glasgow, J R; Parkin, K [N.E.I. Nuclear Systems Ltd., Gateshead, Tyne and Wear (United Kingdom)

1984-07-01

The current AGR Steam Generator is a development of the successful once-through units supplied for the Oldbury Magnox and Hinkley B/Hunterston B AGR power stations. In this paper a brief outline of the evolution of the steam generator design from the earlier gas cooled reactor stations is presented. A description of the main items of fabrication development is given. The production facilities for the manufacture of the units are described. Reference is also made to some of the work on associated components. The early experience on the construction site of installation of the steam generators is briefly outlined. (author)

Investigation of Coating Performance of UV-Curable Hybrid Polymers Containing 1H,1H,2H,2H-Perfluorooctyltriethoxysilane Coated on Aluminum Substrates

Directory of Open Access Journals (Sweden)

Mustafa Çakır

2017-03-01

Full Text Available This study describes preparation and characterization of fluorine-containing organic-inorganic hybrid coatings. The organic part consists of bisphenol-A glycerolate (1 glycerol/phenol diacrylate resin and 1,6-hexanediol diacrylate reactive diluent. The inorganically rich part comprises trimethoxysilane-terminated urethane, 1H,1H,2H,2H-perfluorooctyltriethoxysilane, 3-(trimethoxysilyl propyl methacrylate and sol–gel precursors that are products of hydrolysis and condensation reactions. Bisphenol-A glycerolate (1 glycerol/phenol diacrylate resin was added to the inorganic part in predetermined amounts. The resultant mixture was utilized in the preparation of free films as well as coatings on aluminum substrates. Thermal and mechanical tests such as DSC, thermo-gravimetric analysis (TGA, and tensile and shore D hardness tests were performed on free films. Water contact angle, gloss, Taber abrasion test, cross-cut and tubular impact tests were conducted on the coated samples. SEM examination and EDS analysis was performed on the fractured surfaces of free films. The hybrid coatings on the aluminum sheets gave rise to properties such as moderately glossed surface; low wear rate and hydrophobicity. Tensile strength of free films increased with up to 10% inorganic content in the hybrid structure and this increase was approximately three times that of the control sample. As expected; the % strain value decreased by 17.3 with the increase in inorganic content and elastic modulus values increased by a factor of approximately 6. Resistance to ketone-based solvents was proven and an increase in hardness was observed as the ratio of the inorganic part increased. Samples which contain 10% sol–gel content were observed to provide optimal properties.

Eficiência energética de um trator agrícola utilizando duas configurações de tomada de potência

Directory of Open Access Journals (Sweden)

Ulisses Giacomini Frantz

2014-07-01

Full Text Available A tomada de potência (TDP de um trator agrícola tem por principal finalidade transmitir a potência gerada no motor, para acionamento de órgãos ativos das máquinas agrícolas. Tendo em vista a necessidade de se aumentar a eficiência energética na agricultura, alguns fabricantes disponibilizam para os agricultores uma configuração de TDP que proporciona o acionamento dessas máquinas a um regime de rotação menor do motor do trator. Assim, a rotação da TDP é mantida podendo-se obter uma redução do consumo de combustível. Este trabalho objetivou quantificar o consumo de combustível de um trator agrícola, operando com duas configurações de TDP (normal e econômica em duas áreas agrícolas de relevo distinto. Como resultado, evidencia-se que, com a utilização da TDP econômica, tanto o consumo horário quanto o consumo operacional de combustível, em ambas as áreas trabalhadas, foi menor quando comparado à TDP normal.

The Agr quorum-sensing system regulates fibronectin binding but not hemolysis in the absence of a functional electron transport chain.

Science.gov (United States)

Pader, Vera; James, Ellen H; Painter, Kimberley L; Wigneshweraraj, Sivaramesh; Edwards, Andrew M

2014-10-01

Staphylococcus aureus is responsible for numerous chronic and recurrent infections, which are frequently associated with the emergence of small-colony variants (SCVs) that lack a functional electron transport chain. SCVs exhibit enhanced expression of fibronectin-binding protein (FnBP) and greatly reduced hemolysin production, although the basis for this is unclear. One hypothesis is that these phenotypes are a consequence of the reduced Agr activity of SCVs, while an alternative is that the lack of a functional electron transport chain and the resulting reduction in ATP production are responsible. Disruption of the electron transport chain of S. aureus genetically (hemB and menD) or chemically, using 2-n-heptyl-4-hydroxyquinoline N-oxide (HQNO), inhibited both growth and Agr activity and conferred an SCV phenotype. Supplementation of the culture medium with synthetic autoinducing peptide (sAIP) significantly increased Agr expression in both hemB mutant strains and S. aureus grown with HQNO and significantly reduced staphylococcal adhesion to fibronectin. However, sAIP did not promote hemolysin expression in hemB mutant strains or S. aureus grown with HQNO. Therefore, while Agr regulates fibronectin binding in SCVs, it cannot promote hemolysin production in the absence of a functional electron transport chain. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Entre a propriedade e o salário. Memórias dos trabalhos agrícolas em Alpiarça (anos 50/80)

OpenAIRE

Dulce Freire

2006-01-01

Até aos anos 60 do século XX, Portugal foi um país essencialmente agrícola e rural. O rápido êxodo rural facilitou o abandono ou a transformação da agricultura. Apresenta-se aqui uma reflexão sobre os actuais processos de rememoração das práticas agrícolas numa vila do Ribatejo (Portugal) e sobre a amnésia social verificada relativamente ao passado agrícola, que decorre das transformações ocorridas e dos valores sociais e culturais associados à reconstrução da identidade da vila de Alp...

Entre a propriedade e o salário. Memórias dos trabalhos agrícolas em Alpiarça (anos 50/80

Directory of Open Access Journals (Sweden)

Dulce Freire

2006-09-01

Full Text Available Até aos anos 60 do século XX, Portugal foi um país essencialmente agrícola e rural. O rápido êxodo rural facilitou o abandono ou a transformação da agricultura. Apresenta-se aqui uma reflexão sobre os actuais processos de rememoração das práticas agrícolas numa vila do Ribatejo (Portugal e sobre a amnésia social verificada relativamente ao passado agrícola, que decorre das transformações ocorridas e dos valores sociais e culturais associados à reconstrução da identidade da vila de Alpiarça.

Advanced Marine Coatings for Naval Vessels - Phase 1. Antifouling and Fouling Release Coatings

National Research Council Canada - National Science Library

McCarthy, Gregory

2003-01-01

... in combinatorial materials chemistry high-throughput discovery and evaluation methodology. The protective coatings application being addressed is environmentally compliant antifouling and fouling release coating for Navy ships...

LCA of strippable coatings and of steam vacuum technology used for nuclear plants decontamination

International Nuclear Information System (INIS)

Guidi, Giambattista; Cumo, Fabrizio; Santoli, Livio de

2010-01-01

The application of strippable coatings is an innovative technology for decontamination of nuclear plants and for any decontamination project aiming at removing surface contamination. An adhesive plastic coating is applied on the contaminated surface. The strippable coating is allowed to cure for up to 24 h, after which it can be easily peeled. The coating traps the contaminants in the polymer matrix. Strippable coatings are non-toxic and do not contain volatile compounds or heavy metals. Since the coating constitutes a solid waste, disposal is easier than treating contaminated liquid wastes, produced by the baseline technology: steam vacuum cleaning, based upon superheated pressurized water in order to remove contaminants from floors and walls. A life cycle assessment (LCA) has been carried out with the purpose of comparing the strippable coating with the steam vacuum technology. The functional unit of the study is represented by a surface of 1 m 2 to be decontaminated. The results of LCA achieved using Sima Pro 5.0 registered software confirm the good environmental performances of strippable coatings. Taking into account both LCA and environmental costs for liquid wastes, the advantages of strippable coatings will be more and more evident. (orig.)

The tribology of PS212 coatings and PM212 composites for the lubrication of titanium 6A1-4V components of a Stirling engine space power system

Science.gov (United States)

Sliney, Harold E.; Dellacorte, Christopher; Lukaszewicz, Victor

1995-01-01

The Stirling space power machine incorporates a linear alternator to generate electrical power. The alternator is a reciprocating device that is driven by a solar or nuclear-powered Stirling engine. The power piston and cylinder are made of titanium 6A1-4V (Ti6-4) alloy, and are designed to be lubricated by a hydrodynamically-generated gas film. Rubbing occurs during starts and stops and there is a possibility of an occasional high speed rub. Since titanium is known to have a severe galling tendency in sliding contacts, a 'backup,' self-lubricating coating on the cylinder and/or the piston is needed. This report describes the results of a research program to study the lubrication of Ti6-4 with the following chromium carbide based materials: plasma-sprayed PS212 coatings and sintered PM212 counterfaces. Program objectives are to achieve adherent coatings on Ti6-4 and to measure the friction and wear characteristics of the following sliding combinations under conditions simulative of the Stirling-driven space power linear alternator: Ti6-4/Ti6-4 baseline, Ti6-4/PS212 coated Ti6-4, and Ps212 coated Ti6-4/PM212

Physicochemical characterization and failure analysis of military coating systems

Science.gov (United States)

Keene, Lionel Thomas

Modern military coating systems, as fielded by all branches of the U.S. military, generally consist of a diverse array of organic and inorganic components that can complicate their physicochemical analysis. These coating systems consist of VOC-solvent/waterborne automotive grade polyurethane matrix containing a variety of inorganic pigments and flattening agents. The research presented here was designed to overcome the practical difficulties regarding the study of such systems through the combined application of several cross-disciplinary techniques, including vibrational spectroscopy, electron microscopy, microtomy, ultra-fast laser ablation and optical interferometry. The goal of this research has been to determine the degree and spatial progression of weathering-induced alteration of military coating systems as a whole, as well as to determine the failure modes involved, and characterizing the impact of these failures on the physical barrier performance of the coatings. Transmission-mode Fourier Transform Infrared (FTIR) spectroscopy has been applied to cross-sections of both baseline and artificially weathered samples to elucidate weathering-induced spatial gradients to the baseline chemistry of the coatings. A large discrepancy in physical durability (as indicated by the spatial progression of these gradients) has been found between older and newer generation coatings. Data will be shown implicating silica fillers (previously considered inert) as the probable cause for this behavioral divergence. A case study is presented wherein the application of the aforementioned FTIR technique fails to predict the durability of the coating system as a whole. The exploitation of the ultra-fast optical phenomenon of femtosecond (10-15S) laser ablation is studied as a potential tool to facilitate spectroscopic depth profiling of composite materials. Finally, the interferometric technique of Phase Shifting was evaluated as a potential high-sensitivity technique applied to the

Necesidades educacionales sobre riesgo de plaguicidas en el contexto socio-ambiental de las comunidades agrícolas de Sonora

OpenAIRE

Silveira Gramont, M.I.; Aldana Madrid, L.; Valenzuela Quintanar, A.I.; Ochoa Nogales, C.B.; Jasa-Silveira, G.; Camarena Gómez, Beatriz

2016-01-01

Resumen Introducción: Para proponer estrategias de educación y comunicación sobre plaguicidas en las comunidades agrícolas de Sonora, se requiere situar la problemática de la exposición a plaguicidas en el contexto socio-cultural y ambiental de las comunidades afectadas, tomando en cuenta los factores que contribuyen al mayor riesgo de exposición de los trabajadores agrícolas y de sus familias. Este estudio examina los factores poblacionales, educacionales, culturales y de trabajo de habita...

Qualidade do emprego e condições de vida dos empregados assalariados rurais agrícolas e não agrícolas das mesorregiões mais e menos modernizadas do Estado de Minas Gerais : um estudo entre os anos 2000 a 2010

OpenAIRE

Gandolfi, Maria Raquel Caixeta

2016-01-01

Este trabalho tem como objetivo contribuir com os estudos em torno da qualidade do emprego e condições de vida da força de trabalho residente no setor rural das Mesorregiões de Minas Gerais, especificamente, o empregado assalariado. O recorte compreende as Mesorregiões de Minas Gerais, separadas por mais e menos modernizadas nas culturas do café, cana-de-açúcar e milho, envolvendo os empregados e as famílias agrícolas. Considerando a queda dos empregos agrícolas ocorridos na dé...

Staphylococcus aureus but not Listeria monocytogenes adapt to triclosan and adaptation correlates with increased fabI expression and agr deficiency

DEFF Research Database (Denmark)

Nielsen, Lene Nørby; Larsen, Marianne Halberg; Skovgaard, Sissel

2013-01-01

was initially 4 mg/L and remained unaltered by the exposure. The adapted S. aureus isolates retained normal colony size but displayed increased expression of fabI encoding an essential enzyme in bacterial fatty acid synthesis. Also, they displayed decreased or no expression of the virulence associated agr......C of the agr quorum sensing system. While most adapted strains of USA300 carried mutations in fabI, none of the adapted strains of 8325-4 did. Conclusions. Adaptability to triclosan varies substantially between Gram positive human pathogens. S. aureus displayed an intrinsically lower MIC for triclosan compared...... to L. monocytogenes but was easily adapted leading to the same MIC as L. monocytogenes. Even though all adapted S. aureus strains over-expressed fabI and eliminated expression of the agr quorum sensing system, adaptation in USA300 involved fabI mutations whereas this was not the case for 8325-4. Thus...

Presence of Classical Enterotoxin Genes, agr Typing, Antimicrobial Resistance, and Genetic Diversity of Staphylococcus aureus from Milk of Cows with Mastitis in Southern Brazil.

Science.gov (United States)

Kroning, Isabela S; Iglesias, Mariana A; Mendonça, Karla S; Lopes, Graciela V; Silva, Wladimir P

2018-05-01

Staphylococcus aureus is a common causative agent of bovine mastitis in dairy cows and commonly associated with foodborne disease outbreaks. The aim of this study was to evaluate the presence of enterotoxin genes, agr typing, antimicrobial resistance, and genetic diversity of S. aureus isolated from milk of cows with mastitis in dairy farms from southern Brazil. Results showed that 7 (22.6%) of 31 S. aureus isolates were positive for enterotoxin genes. Specifically, the genes encoding for enterotoxins A ( n = 4), C ( n = 2), and B ( n = 1) were detected. Isolates belonging to the agr group III (10 of 31, 32.2%) and agr group I (7 of 31, 22.5%) were the most common. To our knowledge, this is the first report of both agr I and III in the same S. aureus isolate from milk of cows with bovine mastitis. The antimicrobial resistance test showed that 54% of the isolates were multiresistant to antimicrobial agents. The macrorestriction analysis produced 16 different major SmaI pulsed-field gel electrophoresis patterns, with up to two subpatterns. Moreover, the presence of some S. aureus clones in a distinct area was observed. Although this study characterized a limited number of S. aureus isolates, the presence of classical enterotoxin genes and resistance to multiple antimicrobial agents reinforces the importance of this microorganism to animal and human health. In addition, similar genetic profiles have been identified in distinct geographic areas, suggesting clonal dissemination of S. aureus in dairy herds from southern Brazil.

Orientación Agrícola

Directory of Open Access Journals (Sweden)

Gutiérrez E. Jorge

1941-06-01

Full Text Available Ya estamos sintiendo los efectos de la Guerra Europea y pocos son los preparativos que tenemos para organizar nuestra defensa. Al referirme a preparativos, no tengo en cuenta 108 militares, sino aquellos de carácter agrícola, base de todas las actividades en el orden económico. Cierto que los poderes legislativo y ejecutivo se han preocupado del problema, pero a mi modo de ver, en proporciones muy reducidas por carencia de dinero. Suceden cosas muy curiosas; todos nuestros compatriotas experimentan complacencia cuando se proyecta incrementar la Industria Agropecuaria, nervio y vida de la riqueza pública; el mismo legislador se contagia del entusiasmo; pero cuando llega el momento de asegurar la obra, apropiando las partidas del caso en los presupuestos, las nobles intenciones se esfuman y así han pasado los años y con ellos la oportunidad de hacemos fuertes.

El desarrollo tecnológico y la evolución de la frontera agrícola en el período 1961-2009

OpenAIRE

Casal, Luciano Martín

2014-01-01

Se analizó la evolución de la frontera agrícola argentina y su relación con el cambio tecnológico sucedido para el período 1961-2009, en particular de los activos fijos tangibles como la maquinaria agrícola, además de los cambios en la función de producción. Se buscó verificar la existencia de una relación funcional importante de largo plazo entre el aumento del capital fijo tangible y los cambios en la función de producción, para explicar la evolución de la frontera agrícola. Si bien la fron...

Daily Thermal Predictions of the AGR-1 Experiment with Gas Gaps Varying with Time

Energy Technology Data Exchange (ETDEWEB)

Grant Hawkes; James Sterbentz; John Maki; Binh Pham

2012-06-01

A new daily as-run thermal analysis was performed at the Idaho National Laboratory on the Advanced Gas Reactor (AGR) test experiment number one at the Advanced Test Reactor (ATR). This thermal analysis incorporates gas gaps changing with time during the irradiation experiment. The purpose of this analysis was to calculate the daily average temperatures of each compact to compare with experimental results. Post irradiation examination (PIE) measurements of the graphite holder and fuel compacts showed the gas gaps varying from the beginning of life. The control temperature gas gap and the fuel compact – graphite holder gas gaps were linearly changed from the original fabrication dimensions, to the end of irradiation measurements. A steady-state thermal analysis was performed for each daily calculation. These new thermal predictions more closely match the experimental data taken during the experiment than previous analyses. Results are presented comparing normalized compact average temperatures to normalized log(R/B) Kr-85m. The R/B term is the measured release rate divided by the predicted birth rate for the isotope Kr-85m. Correlations between these two normalized values are presented.

Preliminary coating design and coating developments for ATHENA

DEFF Research Database (Denmark)

Jakobsen, Anders Clemen; Ferreira, Desiree Della Monica; Christensen, Finn Erland

2011-01-01

We present initial novel coating design for ATHENA. We make use of both simple bilayer coatings of Ir and B4C and more complex constant period multilayer coatings to enhance the effective area and cover the energy range from 0.1 to 10 keV. We also present the coating technology used...... for these designs and present test results from coatings....

Office of Geologic Repositories program baseline procedures notebook (OGR/B-1)

International Nuclear Information System (INIS)

1986-06-01

Baseline management is typically applied to aid in the internal control of a program by providing consistent programmatic direction, control, and surveillance to an evolving system development. This fundamental concept of internal program control involves the establishment of a baseline to serve as a point of departure for consistent technical program coordination and to control subsequent changes from that baseline. The existence of a program-authorized baseline ensures that all participants are working to the same ground rules. Baseline management also ensures that, once the baseline is defined, changes are assessed and approved by a process which ensures adequate consideration of overall program impact. Baseline management also includes the consideration of examptions from the baseline. The process of baseline management continues through all the phases of an evolving system development program. As the Program proceeds, there will be a progressive increase in the data contained in the baseline documentation. Baseline management has been selected as a management technique to aid in the internal control of the Office of Geologic Repositories (OGR) program. Specifically, an OGR Program Baseline, including technical and programmatic requirements, is used for program control of the four Mined Geologic Disposal System field projects, i.e., Basalt Waste Isolation Project, Nevada Nuclear Waste Storage Investigation, Salt Repository Project and Crystalline Repository Project. This OGR Program Baseline Procedures Notebook provides a description of the baseline mwanagement concept, establishes the OGR Program baseline itself, and provides procedures to be followed for controlling changes to that baseline. The notebook has a controlled distribution and will be updated as required

PHO1 Exports Phosphate from the Chalazal Seed Coat to the Embryo in Developing Arabidopsis Seeds.

Science.gov (United States)

Vogiatzaki, Evangelia; Baroux, Célia; Jung, Ji-Yul; Poirier, Yves

2017-10-09

Seed production requires the transfer of nutrients from the maternal seed coat to the filial endosperm and embryo. Because seed coat and filial tissues are symplasmically isolated, nutrients arriving in the seed coat via the phloem must be exported to the apoplast before reaching the embryo. Proteins implicated in the transfer of inorganic phosphate (Pi) from the seed coat to the embryo are unknown despite seed P content being an important agronomic trait. Here we show that the Arabidopsis Pi exporters PHO1 and PHOH1 are expressed in the chalazal seed coat (CZSC) of developing seeds. PHO1 is additionally expressed in developing ovules. Phosphorus (P) content and Pi flux between the seed coat and embryo were analyzed in seeds from grafts between WT roots and scions from either pho1, phoh1, or the pho1 phoh1 double mutant. Whereas P content and distribution between the seed coat and embryo in fully mature dry seeds of these mutants are similar to the WT, at the mature green stage of seed development the seed coat of the pho1 and pho1 phoh1 mutants, but not of the phoh1 mutant, retains approximately 2-fold more P than its WT control. Expression of PHO1 under a CZSC-specific promoter complemented the seed P distribution phenotype of the pho1 phoh1 double mutant. CZSC-specific down-expression of PHO1 also recapitulated the seed P distribution phenotype of pho1. Together, these experiments show that PHO1 expression in the CZSC is important for the transfer of P from the seed coat to the embryo in developing seeds. Copyright © 2017 Elsevier Ltd. All rights reserved.

State, Bank and Agricultural Credit in Sinaloa and Sonora: The Banco de Sinaloa and Banco Agrícola Sonorense, 1933-1976 Estado, banca y crédito agrícola en Sinaloa y Sonora: El Banco de Sinaloa y el Banco Agrícola Sonorense, 1933-1976

Directory of Open Access Journals (Sweden)

Gustavo Aguilar Aguilar

2011-01-01

Full Text Available In the Northwest of México the increase in the agricultural productivity in the years between 1940 and 1970, was due to the expansion of the farming lands, the use of improved seeds and fertilizer, mechanization, the greater availability of credit, the irrigation system and road improvement. The important intervention from the Mexican state to implement policies of investment with the support of internationally development agencies, and grant credit facilities for the development of agriculture trough the creation of official agricultural banks and the facilities to the constitution of private commercial banks. After the disarticulation of the bank in México due to the revolution, is advanced with steady steps in restructuring the banking system with the creation of a new banking law, the foundation of Banco de México and the Comision Nacional Bancaria in 1924; Banco Nacional de Credito Agricola (1926, the Banco Nacional de Credito Ejidal (1935, Banco Nacional de Comercio Exterior (1937 and the Banco Nacional Agropecuario (1965, which gave financial support to small farmers and ejidatarios (members of a cooperative. The main farmers of Sinaloa and Sonora in collaboration with the federal government through the Comision Monetaria and the Banco de México founded the Banco de Sinaloa and Banco Agricola Sonorense in 1933. Explain the impact these financial institutions had in the agricultural credit of Sinaloa and Sonora will be the central objective of this work.En el Noroeste de México el incremento en la productividad agrícola entre los años de 1940 y 1970, fue debido a la expansión de las tierras de cultivo, el uso de fertilizantes y semillas mejoradas, la mecanización, la mayor disponibilidad de créditos, a los sistemas de irrigación y el mejoramiento de las carreteras. Así como la importante intervención del Estado mexicano al implementar políticas de inversión con el apoyo de agencias internacionales de desarrollo, y otorgar

Estructura económica nacional: breve análisis del sector agrícola ecuatoriano

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Jorge González-Sarango

2015-12-01

Full Text Available La estructura económica del Ecuador se ha basado, tradicionalmente, en el sector agrícola, el cual enfrenta un panorama económico mundial desalentador. El actual, pero bajo, precio del petróleo, podría incentivar a los importadores de materias primas, pero a la vez complicaría la situación de los exportadores de productos agrícolas, especialmente en economías, como la ecuatoriana, que no cuentan con estrategias de mejora de los niveles de productividad ante el régimen de tipo de cambio flexible de las economías vecinas y de aquellas que demandan bienes nacionales, es decir, que no pueden devaluar la moneda, para compensar el impacto de las pérdidas en los términos de intercambio de la demanda, que genera el abaratamiento del petróleo. Por otra parte, la tasa de crecimiento de la economía ecuatoriana ha tenido que ser replanteada ante los cambios en el contexto mundial, lo cual puede significar, un retroceso en cuanto a la planeación estatal y la determinación del Presupuesto General del Estado para el 2016. En este escenario, el sector agrícola de Ecuador, se ve abocado a contribuir con un porcentaje –cada vez mayor– a la composición del Producto Interno Bruto, sin contar con incentivos ni mejoras dirigidas precisamente a impulsar este sector.

Coat colour phenotype of Qingyu pig is associated with polymorphisms of melanocortin receptor 1 gene.

Science.gov (United States)

Wu, Xiaoqian; Tan, Zhendong; Shen, Linyuan; Yang, Qiong; Cheng, Xiao; Liao, Kun; Bai, Lin; Shuai, Surong; Li, Mingzhou; Li, Xuewei; Zhang, Shunhua; Zhu, Li

2017-07-01

Qingyu pig, a Chinese indigenous pig breed, exhibits two types of coat colour phenotypes, including pure black and white with black spotting respectively. Melanocortin receptor 1 ( MC1R ) and agouti signaling protein ( ASIP ) are two widely reported pivotal genes that significantly affect the regulation of coat colour. The objectives of this study were to investigate whether the polymorphisms of these two genes are associated with coat colour and analyze the molecular mechanism of the coat colour separation in Qingyu pig. We studied the phenotype segregation and used polymerase chain reaction amplification and Sanger sequencing to investigate the polymorphism of MC1R and ASIP in 121 Qingyu pigs, consisting of 115 black and 6 white with black spotted pigs. Coat colour of Qingyu pig is associated with the polymorphisms of MC1R but not ASIP . We only found 2 haplotypes, E QY and E qy , based on the 13 observed mutations from MC1R gene. Among which, E qy presented a recessive inheritance mode in black spotted Qingyu pigs. Further analysis revealed a g.462-463CC insertion that caused a frameshift mutation and a premature stop codon, thus changed the first transmembrane domain completely and lost the remaining six transmembrane domains. Altogether, our results strongly support that the variety of Qingyu pig's coat colour is related to MC1R . Our findings indicated that black coat colour in Qingyu pig was dominant to white with black spotted phenotype and MC1R gene polymorphism was associated with coat colour separation in Qingyu pig.

Coat colour phenotype of Qingyu pig is associated with polymorphisms of melanocortin receptor 1 gene

Directory of Open Access Journals (Sweden)

Xiaoqian Wu

2017-07-01

Full Text Available Objective Qingyu pig, a Chinese indigenous pig breed, exhibits two types of coat colour phenotypes, including pure black and white with black spotting respectively. Melanocortin receptor 1 (MC1R and agouti signaling protein (ASIP are two widely reported pivotal genes that significantly affect the regulation of coat colour. The objectives of this study were to investigate whether the polymorphisms of these two genes are associated with coat colour and analyze the molecular mechanism of the coat colour separation in Qingyu pig. Methods We studied the phenotype segregation and used polymerase chain reaction amplification and Sanger sequencing to investigate the polymorphism of MC1R and ASIP in 121 Qingyu pigs, consisting of 115 black and 6 white with black spotted pigs. Results Coat colour of Qingyu pig is associated with the polymorphisms of MC1R but not ASIP. We only found 2 haplotypes, EQY and Eqy, based on the 13 observed mutations from MC1R gene. Among which, Eqy presented a recessive inheritance mode in black spotted Qingyu pigs. Further analysis revealed a g.462–463CC insertion that caused a frameshift mutation and a premature stop codon, thus changed the first transmembrane domain completely and lost the remaining six transmembrane domains. Altogether, our results strongly support that the variety of Qingyu pig’s coat colour is related to MC1R. Conclusion Our findings indicated that black coat colour in Qingyu pig was dominant to white with black spotted phenotype and MC1R gene polymorphism was associated with coat colour separation in Qingyu pig.

A novel approach for baseline correction in 1H-MRS signals based on ensemble empirical mode decomposition.

Science.gov (United States)

Parto Dezfouli, Mohammad Ali; Dezfouli, Mohsen Parto; Rad, Hamidreza Saligheh

2014-01-01

Proton magnetic resonance spectroscopy ((1)H-MRS) is a non-invasive diagnostic tool for measuring biochemical changes in the human body. Acquired (1)H-MRS signals may be corrupted due to a wideband baseline signal generated by macromolecules. Recently, several methods have been developed for the correction of such baseline signals, however most of them are not able to estimate baseline in complex overlapped signal. In this study, a novel automatic baseline correction method is proposed for (1)H-MRS spectra based on ensemble empirical mode decomposition (EEMD). This investigation was applied on both the simulated data and the in-vivo (1)H-MRS of human brain signals. Results justify the efficiency of the proposed method to remove the baseline from (1)H-MRS signals.

Planificación de Maquinaria Agrícola

Directory of Open Access Journals (Sweden)

Alvarez Cardona Alberto

1979-06-01

Full Text Available Se entiende por planificación agrícola el conjunto de técnicas que permiten ver con anticipación suficiente la cantidad de maquinaria, tanto fuentes de potencia como implementos que serán requeridos para realizar un trabajo específico en un tiempo determinado; ó la cantidad de trabajo específico que podrá realizar un equipo con características ya definidas a través de un tiempo determinado; se analizan también bajo este concepto de planificación aquellos sistemas que permiten evaluar, controlar y ajustar la planificación propuesta a las circunstancias reales una vez iniciada ésta.

For sale: 7 AGR stations and a brand new PWR

International Nuclear Information System (INIS)

Anon.

1995-01-01

Britain's seven AGR stations and the Sizewell B PWR will pass to private ownership under the UK government's plan to privatise the two nuclear generators, Nuclear Electric and Scottish Nuclear, sometime next year. Under the new set-up, the two generators will become operating subsidiaries of a holding company which will be headquartered in Scotland. The companies' ageing Magnox gas-cooled reactors will remain in a separate public sector company before being transferred to British Nuclear Fuels (BNFL) at the time of privatisation. (author)

Plasma effects on the passive external thermal control coating of Space Station Freedom

Science.gov (United States)

Carruth, Ralph, Jr.; Vaughn, Jason A.; Holt, James M.; Werp, Richard; Sudduth, Richard D.

1992-01-01

The current baseline chromic acid anodized thermal control coating on 6061-T6 aluminum meteoroid debris (M/D) shields for SSF has been evaluated. The degradation of the solar absorptance, alpha, and the thermal emittance, epsilon, of chromic acid anodized aluminum due to dielectric breakdown in plasma was measured to predict the on-orbit lifetime of the SSF M/D shields. The lifetime of the thermal control coating was based on the surface temperatures achieved with degradation of the thermal control properties, alpha and epsilon. The temperatures of each M/D shield from first element launch (FEL) through FEL+15 years were analyzed. It is shown that the baseline thermal control coating cannot withstand the -140 V potential between the conductive structure of the SSF and the current plasma environment.

Targeting In-Stent-Stenosis with RGD- and CXCL1-Coated Mini-Stents in Mice.

Science.gov (United States)

Simsekyilmaz, Sakine; Liehn, Elisa A; Weinandy, Stefan; Schreiber, Fabian; Megens, Remco T A; Theelen, Wendy; Smeets, Ralf; Jockenhövel, Stefan; Gries, Thomas; Möller, Martin; Klee, Doris; Weber, Christian; Zernecke, Alma

2016-01-01

Atherosclerotic lesions that critically narrow the artery can necessitate an angioplasty and stent implantation. Long-term therapeutic effects, however, are limited by excessive arterial remodeling. We here employed a miniaturized nitinol-stent coated with star-shaped polyethylenglycole (star-PEG), and evaluated its bio-functionalization with RGD and CXCL1 for improving in-stent stenosis after implantation into carotid arteries of mice. Nitinol foils or stents (bare metal) were coated with star-PEG, and bio-functionalized with RGD, or RGD/CXCL1. Cell adhesion to star-PEG-coated nitinol foils was unaltered or reduced, whereas bio-functionalization with RGD but foremost RGD/CXCL1 increased adhesion of early angiogenic outgrowth cells (EOCs) and endothelial cells but not smooth muscle cells when compared with bare metal foils. Stimulation of cells with RGD/CXCL1 furthermore increased the proliferation of EOCs. In vivo, bio-functionalization with RGD/CXCL1 significantly reduced neointima formation and thrombus formation, and increased re-endothelialization in apoE-/- carotid arteries compared with bare-metal nitinol stents, star-PEG-coated stents, and stents bio-functionalized with RGD only. Bio-functionalization of star-PEG-coated nitinol-stents with RGD/CXCL1 reduced in-stent neointima formation. By supporting the adhesion and proliferation of endothelial progenitor cells, RGD/CXCL1 coating of stents may help to accelerate endothelial repair after stent implantation, and thus may harbor the potential to limit the complication of in-stent restenosis in clinical approaches.

Redescubriendo El suelo: Su importancia ecológica y agrícola

Directory of Open Access Journals (Sweden)

Noé Manuel Montaño

2016-10-01

Full Text Available Redescubriendo el suelo: su importancia ecológica y agrícola es un libro muy completo, actualizado y sin duda será de consulta obligada para quienes hacen investigación edafológica y como material elemental para los cursos de pre- y posgrado de suelo y materias afines, tanto en México como en América Latina.

Canvi d'us d'una nau agrícola a restaurant vinícola : el celler dels Mora

OpenAIRE

Mora Aller, Elisa

2017-01-01

El present treball fi de carrera tracta sobre el canvi d’ús d’una nau agrícola a restaurant vinícola. La nau es troba situada a la capital del vi, Vilafranca del Penedès. Durant els darrers anys, hi ha hagut un creixement important pel que fa al turisme del vi, a la zona de l’Alt Penedès. L’edifici objecte d’estudi, va ser construït pel meu avi a l’any 1980. Antigament, s’utilitzava per a guardar el bestiar i les eines agrícoles. Actualment, no hi ha bestiar, només s’utilitza per a guardar...

EPA R1 RCRA Corrective Action 2020 Baseline Site Property Boundaries

Data.gov (United States)

U.S. Environmental Protection Agency — Property boundaries as indicated in figures of all facilities subject to RCRA Corrective Action on the 2020 baseline in Region 1. For more information on the RCRA...

Measurement techniques for AGR circulators in a full-density rig

International Nuclear Information System (INIS)

Watson, I.; Wilson, R.R.

1977-01-01

Safety and reliability are the most important factors of a nuclear power plant. This applies in particular to the circulators used to drive the high-density CO 2 around the reactor core and boiler circuits. Under operating conditions, very high sound-pressure levels are generated which could excite components and cause possible fatigue failures. Failures of this type were experienced on the original axial blowers for the Hinkley 'A' Magnox reactor and, following this, a stringent test plan was specified for the AGR circulators. The present paper describes some of the techniques used to measure strain, sound and vibration on circulators in a full-density rig. This rig reproduces the actual reactor working conditions of 300 0 C and 4.1 MN m -2 with gas velocities up to 120 m s -1 . Under these conditions sound-pressure levels of up to 172 dB are generated. This programme of circulator testing has continued for the past 10 years. During this period many obstacles and difficulties were encountered. Some of these problems, together with the solutions found, are discussed. (author)

Assessment of background gamma radiation levels using airborne gamma ray spectrometer data over uranium deposits, Cuddapah Basin, India - A comparative study of dose rates estimated by AGRS and PGRS.

Science.gov (United States)

Srinivas, D; Ramesh Babu, V; Patra, I; Tripathi, Shailesh; Ramayya, M S; Chaturvedi, A K

2017-02-01

The Atomic Minerals Directorate for Exploration and Research (AMD) has conducted high-resolution airborne gamma ray spectrometer (AGRS), magnetometer and time domain electromagnetic (TDEM) surveys for uranium exploration, along the northern margins of Cuddapah Basin. The survey area includes well known uranium deposits such as Lambapur-Peddagattu, Chitrial and Koppunuru. The AGRS data collected for uranium exploration is utilised for estimating the average absorbed rates in air due to radio-elemental (potassium in %, uranium and thorium in ppm) distribution over these known deposit areas. Further, portable gamma ray spectrometer (PGRS) was used to acquire data over two nearby locations one from Lambapur deposit, and the other from known anomalous zone and subsequently average gamma dose rates were estimated. Representative in-situ rock samples were also collected from these two areas and subjected to radio-elemental concentration analysis by gamma ray spectrometer (GRS) in the laboratory and then dose rates were estimated. Analyses of these three sets of results complement one another, thereby providing a comprehensive picture of the radiation environment over these deposits. The average absorbed area wise dose rate level is estimated to be 130 ± 47 nGy h -1 in Lambapur-Peddagattu, 186 ± 77 nGy h -1 in Chitrial and 63 ± 22 nGy h -1 in Koppunuru. The obtained average dose levels are found to be higher than the world average value of 54 nGy h -1 . The gamma absorbed dose rates in nGy h -1 were converted to annual effective dose rates in mSv y -1 as proposed by the United Nations Scientific Committee on the Effect of Atomic Radiation (UNSCEAR). The annual average effective dose rates for the entire surveyed area is 0.12 mSv y -1 , which is much lower than the recommended limit of 1 mSv y -1 by International Commission on Radiation protection (ICRP). It may be ascertained here that the present study establishes a reference data set (baseline) in these areas

Program Baseline Change Control Procedure

International Nuclear Information System (INIS)

1993-02-01

This procedure establishes the responsibilities and process for approving initial issues of and changes to the technical, cost, and schedule baselines, and selected management documents developed by the Office of Civilian Radioactive Waste Management (OCRWM) for the Civilian Radioactive Waste Management System. This procedure implements the OCRWM Baseline Management Plan and DOE Order 4700.1, Chg 1. It streamlines the change control process to enhance integration, accountability, and traceability of Level 0 and Level I decisions through standardized Baseline Change Proposal (BCP) forms to be used by the Level 0, 1, 2, and 3 Baseline Change Control Boards (BCCBs) and to be tracked in the OCRWM-wide Configuration Information System (CIS) Database.This procedure applies to all technical, cost, and schedule baselines controlled by the Energy System Acquisition Advisory Board (ESAAB) BCCB (Level 0) and, OCRWM Program Baseline Control Board (PBCCB) (Level 1). All baseline BCPs initiated by Level 2 or lower BCCBs, which require approval from ESAAB or PBCCB, shall be processed in accordance with this procedure. This procedure also applies to all Program-level management documents controlled by the OCRWM PBCCB

Coating of evaporation concentrates with bitumen. Progress Report No. 1

International Nuclear Information System (INIS)

Rodier, J.; Lefillatre, G.; Rodi, L.; Cudel, Y.

1968-01-01

Laboratory tests have been carried out on the coating by bitumen of evaporation concentrates having a free nitric acidity of 1 N or 2.5 N, and a high mineralization (400 gm/litre). In order to neutralize the free acidity and to trap the radio-elements, these concentrates have been subjected before coating to various treatments designed to decrease the solubility. As a result of these treatments, sludges were obtained which could be coated directly with the bitumen. By measuring the radioactive diffusion factors of the bitumen coated products immersed both in ordinary and sea water, it was possible to compare the efficiency of the processes developed and of the various types of bitumen used. On the whole the radioactive diffusion tests were satisfactory and the process using successive co-precipitations (hydroxides, nickel ferrocyanide, barium sulphate) was chosen. From the bitumens tried out, a straight - asphalt, Mexphalt 40/50 was selected for low and medium activity concentrates as it ensures good isolation of the radio-elements; an air-blowing asphalt, Mexphalte R 90/40, was chosen for concentrates of high activity because of its higher resistance to irradiation. As a result of this work, a simple coating technology was evolved and pilot experiments will soon begin. Briefly, it appears that although a method for coating evaporation concentrates with bitumen has been defined, it will inevitably be necessary to devise a specific decontamination process each time that a new type of concentrate is encountered (composition, nature of the salts, radio-element distribution). (author) [fr

La combinación de sistemas agrícolas tradicionales y comerciales, el proceso de conversión en Cruz de Piedra, Estado de México

Directory of Open Access Journals (Sweden)

Leonardo Ernesto Márquez Mireles

2007-01-01

Full Text Available La comprensión de las relaciones establecidas entre la cultura y la agricultura de una población dedicada al cultivo, ubicada en el ecotono, al sur del volcán Nevado de Toluca, en el Estado de México; genera varias preguntas, entre ellas: ¿Cuáles son las transformaciones que han sufrido la organización social y el trabajo agrícola que permiten combinar un sistema agrícola convencional con un sistema agrícola tradicional? La respuesta a la pregunta se deriva en dos rubros: (1 Para que los campesinos dentro del proceso de conversión tengan dinero para la compra de insumos agroindustriales, este debe ingresar a través de actividades asalariadas o de la migración; (2 La conversión implica desarrollar una agricultura de monocultivos y dejar a un lado la diversidad de cultivos de la agricultura tradicional. Los resultados que se presentan a lo largo de este artículo muestran cómo se realizó esta combinación y cuáles fueron los mecanismos de ajuste social y cultural a su ambiente y al mercado.

Periferias e reestruturação agrícola

OpenAIRE

Dentinho, Tomaz; Rodrigues, Orlando

2007-01-01

As regiões vocacionadas par a agricultura encontram-se muitas vezes na situação de perificidade, pois têm produções agrícolas com elevada produtividade e capazes de competir nos mercados externos à sua região mas, devido a falhas de mercado ao longo da cadeia de valor, muito do valor criado a nível a nível regional acaba por gerar rendimento fora da região. Por outro lado são estas mesmas regiões periféricas que sofrem de forma mais notória os impactos das alterações nos mercados dos produtos...

A Study on Performance Evaluation of Safety-Related Protective Coating for Yonggwang Unit 1 and 2

International Nuclear Information System (INIS)

Kim, Sung Young; Kim, Young Bum; Lee, Won Sang

2010-01-01

Protective coating inside nuclear power plants could find its origin from NRC Reg. Guide 1.82(Rev. 3) regarding current issue for the regulation of foreign materials inside containment building. The current issue for the regulation of foreign materials inside containment considered/determined the current issues only regarding the blockage of sump screen by foreign materials such as coating material, insulator, and other materials, while safety-related coating is separately managed by NRC Reg. Guide 1.54(Rev. 1). In this study, we performed field walk-down to evaluate the as-is condition of protective coating inside containment building which was classified as for structure and for equipment with applying the requirement for safety-related coating

Acute cellular rejection is a risk factor for bronchiolitis obliterans syndrome independent of post-transplant baseline FEV1

DEFF Research Database (Denmark)

Burton, C.M.; Iversen, M.; Carlsen, J.

2009-01-01

BACKGROUND: Post-transplant baseline forced expiratory volume in 1 second (FEV(1)) constitutes a systematic bias in analyses of bronchiolitis obliterans syndrome (BOS). This retrospective study evaluates risk factors for BOS adjusting for the confounding of post-transplant baseline FEV(1). METHODS......-specific hazard of BOS (hazard ratio 1.4, confidence interval 1.1 to 1.8, p = 0.009). The absolute value of baseline FEV(1) was a significant confounder in all survival and competing risk analyses of BOS (p ... an independent risk factor for the development of BOS after adjusting for the confounding of post-transplant baseline FEV(1) Udgivelsesdato: 2009/9...

Analise da vulnerabilidade de um solo agrícola, irrigado com águas poluídas

Directory of Open Access Journals (Sweden)

Benjamim Carvalho Lima Junior

2014-08-01

Full Text Available O reúso planejado de água de qualidade inferior contribui para uma gestão melhor dos recursos hídricos, favorecendo a produção agrícola em locais onde este fator de produção é escasso. No semiárido brasileiro a utilização de água de qualidade inferior em sistemas produtivos irrigados é em muitas situações, a única maneira de garantir a produção agrícola. Este trabalho objetivou identificar os impactos salinos em um solo agrícola cultivado com bananicultura irrigada com águas poluídas. Foram avaliados os parâmetros hidrodinâmico do solo condutividade hidráulica (K0, e porosidade drenável (μ, e os parâmetros de classificação salina do solo (pHes, CEes e PST. Foram realizadas análises exploratórias através de métodos estatísticos descritiva dos parâmetros hidrodinâmicos e modelagem geoestatística dos parâmetros de classificação salina. Observou no estudo o solo da área experimental encontra-se degradado por processo de salinização e sodicidade, ação provocada principalmente pela irrigação com água de qualidade inferior e deficiência na drenagem natural do solo.

Metodologia para estimar o número de dias trabalháveis com máquinas agrícolas

OpenAIRE

Estrada,Javier Solis; Schlosser,José Fernando; Farias,Marcelo Silveira de; Santos,Gustavo Oliveira do; Rüdell,Iury Yago Port

2015-01-01

No atual modelo de agricultura, é indispensável que o produtor conheça a real disponibilidade de tempo para a execução das operações agrícolas ao longo do ciclo das culturas. Este é o primeiro passo para se planejar e se obter maior eficiência na execução dessas operações, que estão sujeitas às variações do clima. As variáveis meteorológicas de uma determinada região influenciam diretamente no número de dias disponíveis para trabalhar com máquinas agrícolas. O objetivo deste trabalho foi esti...

Reestructuración agrícola de las familias productoras de maíz: estudio en San Mateo Ayecac, Tlaxcala, 2000-2008.

Directory of Open Access Journals (Sweden)

Ma. Concepción Alvarado Méndez

2011-01-01

Full Text Available La investigación tiene por objetivo analizar el mecanismo de transformación agrícola expresado en los cambios de la fuerza de trabajo agrícola en términos de su estructura económica así como las principales consecuencias económicas en la comunidad de San Mateo Ayecac, municipio de Tepetitla en el estado de Tlaxcala. Los resultados muestran una transformación de las familias productoras de granos básicos, expresados en el proceso productivo, específicamente en la disminución de labores, fertilización, disminución del trabajo familiar y en el rendimiento. A pesar de ello no existe abandono de la actividad agrícola y sigue siendo la base de la alimentación familiar y un importante abastecedor de alimentos de los mercados locales.

European coatings conference - Marine coatings. Proceedings

Energy Technology Data Exchange (ETDEWEB)

NONE

2008-07-01

This volume contains 13 lectures (manuscripts or powerpoint foils) with the following topics: 1. Impact of containerization on polyurethane and polyurea in marine and protective coatings (Malte Homann); 2. The application of combinatorial/high-throughput methods to the development of marine coatings (Bret Chisholm); 3. Progress and perspectives in the AMBIO (advanced nanostructured surfaces for the control of biofouling) Project (James Callow); 4. Release behaviour due to shear and pull-off of silicone coatings with a thickness gradient (James G. Kohl); 5. New liquid rheology additives for high build marine coatings (Andreas Freytag); 6. Effective corrosion protection with polyaniline, polpyrrole and polythiophene as anticorrosice additives for marine paints (Carlos Aleman); 7. Potential applications of sol gel technology for marine applications (Robert Akid); 8: Performance of biocide-free Antifouling Coatings for leisure boats (Bernd Daehne); 9. Novel biocidefree nanostructured antifouling coatings - can nano do the job? (Corne Rentrop); 10. One component high solids, VOC compliant high durability finish technology (Adrian Andrews); 11. High solid coatings - the hybrid solution (Luca Prezzi); 12. Unique organofunctional silicone resins for environmentally friendly high-performance coatings (Dieter Heldmann); 13. Silicone-alkyd paints for marine applications: from battleship-grey to green (Thomas Easton).

Developing RESRAD-BASELINE for environmental baseline risk assessment

International Nuclear Information System (INIS)

Cheng, Jing-Jy.

1995-01-01

RESRAD-BASELINE is a computer code developed at Argonne developed at Argonne National Laboratory for the US Department of Energy (DOE) to perform both radiological and chemical risk assessments. The code implements the baseline risk assessment guidance of the US Environmental Protection Agency (EPA 1989). The computer code calculates (1) radiation doses and cancer risks from exposure to radioactive materials, and (2) hazard indexes and cancer risks from exposure to noncarcinogenic and carcinogenic chemicals, respectively. The user can enter measured or predicted environmental media concentrations from the graphic interface and can simulate different exposure scenarios by selecting the appropriate pathways and modifying the exposure parameters. The database used by PESRAD-BASELINE includes dose conversion factors and slope factors for radionuclides and toxicity information and properties for chemicals. The user can modify the database for use in the calculation. Sensitivity analysis can be performed while running the computer code to examine the influence of the input parameters. Use of RESRAD-BASELINE for risk analysis is easy, fast, and cost-saving. Furthermore, it ensures in consistency in methodology for both radiological and chemical risk analyses

Anti-listerial activity of a polymeric film coated with hybrid coatings doped with Enterocin 416K1 for use as bioactive food packaging.

Science.gov (United States)

Iseppi, Ramona; Pilati, Francesco; Marini, Michele; Toselli, Maurizio; de Niederhäusern, Simona; Guerrieri, Elisa; Messi, Patrizia; Sabia, Carla; Manicardi, Giuliano; Anacarso, Immacolata; Bondi, Moreno

2008-04-30

In this study, Enterocin 416K1, a bacteriocin produced by Enterococcus casseliflavus IM 416K1, was entrapped in an organic-inorganic hybrid coating applied to a LDPE (low-density polyethylene) film for its potential use in the active food packaging field. The antibacterial activity of the coated film was evaluated against Listeria monocytogenes NCTC 10888 by qualitative modified agar diffusion assay, quantitative determination in listeria saline solution suspension and direct contact with artificially contaminated food samples (frankfurters and fresh cheeses) stored at room and refrigeration temperatures. All investigations demonstrated that enterocin-activated coatings have a good anti-listeria activity. Qualitative tests showed a clear zone of inhibition in the indicator lawn in contact with and around the coated film. During the quantitative antibacterial evaluation the L. monocytogenes viable counts decreased to 1.5 log units compared to the control. The inhibitory capability was confirmed also in food-contact assays. In all food samples packed with coated films we observed a significant decrease in L. monocytogenes viable counts in the first 24 h compared to the control. This difference was generally maintained up to the seventh day and then decreased, with the exception of the cheese samples stored at refrigeration temperature.

Feasibility study of aluminum beam tube for the collider: An option for no-coating and no-liner

International Nuclear Information System (INIS)

Chou, W.

1994-07-01

This report proposes to use a single-layer beam tube made of high strength, high resistivity aluminum alloy (such as 7039-T61 or A7N01) to replace the double-layer copper coated stainless steel tube in the SSC Collider. The main reasons are: (1) a potential saving of about $23 million which is basically the baseline cost of the copper coating and (2) the use of an extruded aluminum tube consisting of a beam chamber and a pumping chamber may solve the vacuum problem without any liner

Reproducción de Eisenia foetida en suelos agrícolas de áreas mineras contaminadas por cobre y arsênico.

OpenAIRE

ÁVILA, G.; GAETE, H.; MORALES, M.; NEAMAN, A.

2008-01-01

El objetivo del trabajo fue evaluar la toxicidad del cobre y arsénico en suelos agrícolas, mediante bioensayos estandarizados de toxicidad aguda y crónica sobre Eisenia foetida y relacionar la respuesta de ésta con las concentraciones de cobre y arsénico en los suelos. Los suelos agrícolas fueram muestreados en las inmediaciones de áreas mineras en la cuenca del río Aconcagua, Chile. E. foetida expuesta a los suelos estudiados mostró una baja mortalidad, indicando la ausencia de toxicidad agu...

Políticas trabalhista, fundiária e de crédito agrícola no Brasil

Directory of Open Access Journals (Sweden)

Gervásio Castro de Rezende

2006-03-01

Full Text Available Este artigo discute as causas do padrão concentrador do desenvolvimento agrícola brasileiro recente, expresso no predomínio da produção em grande escala, elevado índice de mecanização e baixa absorção de mão de obra não qualificada. Cita, inicialmente, a existência de duas posições antagônicas que procuram explicar esse fato: uma, que culpa a herança latifundiária de nossa agricultura, e a outra, que vê nisso um determinismo tecnológico, não havendo, assim, possibilidade de atuar sobre esse problema sem incorrer numa perda em termos de eficiência econômica. Este trabalho, contudo, atribui às políticas trabalhista agrícola, fundiária e de crédito agrícola, instituídas na década de 1960, a responsabilidade maior por esse problema. Conforme a análise apresentada, essas políticas inviabilizaram o mercado de trabalho agrícola temporário e a agricultura familiar, ao mesmo tempo em que fomentaram a mecanização agrícola e o predomínio da produção em grande escala. O trabalho termina propondo uma desregulamentação dos mercados de trabalho e de terra na agricultura brasileira, assim como uma redução drástica do subsídio ao crédito rural.This paper discusses the question of the concentrated pattern of agricultural development in Brazil, as expressed in the predominance of large-scale production, high level of mechanization and low absorption of non-qualified labor. It is proposed, initially, the existence of two conflicting explanations for this fact: the first, that blames our historical heritage, characterized by the predominance of the latifundio, and the second, that sees in this fact a technological determinism, with the implication that lesser concentration in agriculture would involve a loss of economic efficiency. This paper, however, attributes to the labor, land and credit policies directed to agriculture, instituted in the decade of 1960, the major responsibility for this problem. As the analysis

Mutations in MC1R Gene Determine Black Coat Color Phenotype in Chinese Sheep

Directory of Open Access Journals (Sweden)

Guang-Li Yang

2013-01-01

Full Text Available The melanocortin receptor 1 (MC1R plays a central role in regulation of animal coat color formation. In this study, we sequenced the complete coding region and parts of the 5′- and 3′-untranslated regions of the MC1R gene in Chinese sheep with completely white (Large-tailed Han sheep, black (Minxian Black-fur sheep, and brown coat colors (Kazakh Fat-Rumped sheep. The results showed five single nucleotide polymorphisms (SNPs: two non-synonymous mutations previously associated with coat color (c.218 T>A, p.73 Met>Lys. c.361 G>A, p.121 Asp>Asn and three synonymous mutations (c.429 C>T, p.143 Tyr>Tyr; c.600 T>G, p.200 Leu>Leu. c.735 C>T, p.245 Ile>Ile. Meanwhile, all mutations were detected in Minxian Black-fur sheep. However, the two nonsynonymous mutation sites were not in all studied breeds (Large-tailed Han, Small-tailed Han, Gansu Alpine Merino, and China Merino breeds, all of which are in white coat. A single haplotype AATGT (haplotype3 was uniquely associated with black coat color in Minxian Black-fur breed (P=9.72E-72, chi-square test. The first and second A alleles in this haplotype 3 represent location at 218 and 361 positions, respectively. Our results suggest that the mutations of MC1R gene are associated with black coat color phenotype in Chinese sheep.

CryoSat Level1b SAR/SARin BaselineC: Product Format and Algorithm Improvements

Science.gov (United States)

Scagliola, Michele; Fornari, Marco; Di Giacinto, Andrea; Bouffard, Jerome; Féménias, Pierre; Parrinello, Tommaso

2015-04-01

CryoSat was launched on the 8th April 2010 and is the first European ice mission dedicated to the monitoring of precise changes in the thickness of polar ice sheets and floating sea ice. Cryosat carries an innovative radar altimeter called the Synthetic Aperture Interferometric Altimeter (SIRAL), that transmits pulses at a high pulse repetition frequency thus making the received echoes phase coherent and suitable for azimuth processing. This allows to reach a significantly improved along track resolution with respect to traditional pulse-width limited altimeters. CryoSat is the first altimetry mission operating in SAR mode and continuous improvements in the Level1 Instrument Processing Facility (IPF1) are being identified, tested and validated in order to improve the quality of the Level1b products. The current IPF, Baseline B, was released in operation in February 2012. A reprocessing campaign followed, in order to reprocess the data since July 2010. After more than 2 years of development, the release in operations of Baseline C is expected in the first half of 2015. BaselineC Level1b products will be distributed in an updated format, including for example the attitude information (roll, pitch and yaw) and, for SAR/SARIN, the waveform length doubled with respect to Baseline B. Moreveor, various algorithm improvements have been identified: • a datation bias of about -0.5195 ms will be corrected (SAR/SARIn) • a range bias of about 0.6730 m will be corrected (SAR/SARIn) • a roll bias of 0.1062 deg and a pitch bias of 0.0520 deg • Surface sample stack weighting to filter out the single look echoes acquired at highest look angle, that results in a sharpening of the 20Hz waveforms With the operational release of BaselineC, the second CryoSat reprocessing campaign will be initiated, taking benefit of the upgrade implemented in the IPF1 processing chain but also at IPF2 level. The reprocessing campaign will cover the full Cryosat mission starting on 16th July 2010

Erosión y pérdida de nutrientes en diferentes sistemas agrícolas de una microcuenca en la zona periurbana de la ciudad de Puebla, México

Directory of Open Access Journals (Sweden)

Rosalía Castelán Vega

2017-07-01

Full Text Available El suelo es un componente natural de gran importancia en la sostenibilidad de los ecosistemas, su degradación se debe, en la mayoría de los casos, al mal manejo bajo condiciones de ladera, lo que disminuye su productividad y su capacidad para sostener la vida humana. Se evaluó la producción de sedimentos y la pérdida de nutrientes durante el año 2013 en sistemas agrícolas representativos de la zona periurbana de la ciudad de Puebla, México; con el objetivo de ponderar el coeficiente de enriquecimiento de dichos sedimentos, y así identificar el sistema agrícola que menor perdida de fertilidad genera. Se instalaron parcelas delimitadas con dimensiones de 3 m de ancho y 9 m de largo con pendiente homogénea de 9% de inclinación, en los sistemas: maíz, maíz-calabaza y maíz-avena. Se recolectaron los sedimentos, a los cuales se les determinó la concentración de materia orgánica, nitrógeno y fósforo, según lo marca la NOM-021-SEMARNAT-2000. La producción de sedimentos y escorrentía fue significativamente mayor en el sistema agrícola de maíz (54.6 mm y 37.9 Mg ha‑1, respectivamente y menor en maíz-calabaza. Los coeficientes de enriquecimiento de los sedimentos erosionados fueron en su mayoría, superiores a la unidad, destacando la materia orgánica con los coeficientes más altos. Se observó una fuerte correlación entre la producción de sedimentos y las pérdidas de materia orgánica, nitrógeno y fósforo, en los sistemas agrícolas. Los resultados obtenidos demuestran que el actual manejo de los cultivos agrícolas en la zona de estudio, favorecen la degradación de los suelos. De igual forma, los resultados generados son una base importante para establecer estrategias agrícolas y disminuir áreas degradadas en los espacios rurales de la zona periurbana de la ciudad de Puebla, México.

9Å structure of the COPI coat reveals that the Arf1 GTPase occupies two contrasting molecular environments.

Science.gov (United States)

Dodonova, Svetlana O; Aderhold, Patrick; Kopp, Juergen; Ganeva, Iva; Röhling, Simone; Hagen, Wim J H; Sinning, Irmgard; Wieland, Felix; Briggs, John A G

2017-06-16

COPI coated vesicles mediate trafficking within the Golgi apparatus and between the Golgi and the endoplasmic reticulum. Assembly of a COPI coated vesicle is initiated by the small GTPase Arf1 that recruits the coatomer complex to the membrane, triggering polymerization and budding. The vesicle uncoats before fusion with a target membrane. Coat components are structurally conserved between COPI and clathrin/adaptor proteins. Using cryo-electron tomography and subtomogram averaging, we determined the structure of the COPI coat assembled on membranes in vitro at 9 Å resolution. We also obtained a 2.57 Å resolution crystal structure of βδ-COP. By combining these structures we built a molecular model of the coat. We additionally determined the coat structure in the presence of ArfGAP proteins that regulate coat dissociation. We found that Arf1 occupies contrasting molecular environments within the coat, leading us to hypothesize that some Arf1 molecules may regulate vesicle assembly while others regulate coat disassembly.

Ensino agrícola e influência norte-americana no Brasil (1945-1961

Directory of Open Access Journals (Sweden)

Sonia Regina de Mendonça

2010-12-01

Full Text Available O artigo trata das redefinições sofridas pelo Ensino Agrícola no Brasil, a partir da conjuntura marcada pelo fim da II Guerra Mundial/Guerra Fria, quando inúmeros acordos de "cooperação técnica" seriam firmados entre os governos brasileiro e estadunidense, objetivando "recuperar" seu novo público-alvo: o trabalhador rural adulto e analfabeto.

Chemical changes in DMP1-null murine bone & silica based pecvd coatings for titanium implant osseoapplications

Science.gov (United States)

Maginot, Megen

In order to improve clinical outcomes in bone-implant systems, a thorough understanding of both local bone chemistry and implant surface chemistry is necessary. This study consists, therefore, of two main parts: one focused on determining the nature of the changes in bone chemistry in a DMP1-null transgenic disease model and the other on the development of amorphous silica-based coatings for potential use as titanium bone implant coatings. For the study of bone mineral in the DMP1 transgenic model, which is known to have low serum phosphate levels, transgenic DMP1-null and wild type mice were fed a high phosphate diet, sacrificed, and had their long bone harvested. This bone was characterized using SEM, FTIR, microCT and XANES and compared to DMP1-null and wild type control groups to assess the therapeutic effect of high Pi levels on the phenotype and the role of DMP1 in mineralization in vivo. Findings suggest that though the high phosphate diet results in restoring serum phosphate levels, it does not completely rescue the bone mineral phenotype at an ultrastructural level and implicates DMP1 in phosphate nucleation. Since plasma enhanced chemical vapor deposition (PECVD) silica like coatings have not previously been fabricated for use in oessoapplications, the second part of this study initially focused on the characterization of novel SiOx chemistries fabricated via a chemical vapor deposition process that were designed specifically to act as bioactive coatings with a loose, hydrogenated structure. These coatings were then investigated for their potential initial stage response to bone tissue through immersion in a simulated body fluid and through the culture of MC3T3 cells on the coating surfaces. Coating surfaces were characterized by SEM, FTIR, contact angle measurements, and XANES. Coating dissolution and ionic release were also investigated by ICP-OES. Findings suggest that some SiOx chemistries may form a bioactive coating while more highly substituted

Caracterización del uso del suelo en las principales áreas agrícolas de la Gran Área Metropolitana (GAM de Costa Rica

Directory of Open Access Journals (Sweden)

Sue Wei-Salas

2015-06-01

Full Text Available Con el objetivo de aportar información para el ordenamiento y la planificación del uso del suelo, mediante la caracterización de su utilización en las regiones agrícolas de la Gran Área Metropolitana (GAM, se realizó una investigación entre marzo 2008 y octubre 2009, por medio de Sistemas de Información Geográfica (SIG. En el estudio se utilizaron imágenes aéreas correspondientes al proyecto Misión Carta capturadas entre febrero y marzo del 2005, lo que permitió identificar la distribución y extensión de los principales cultivos existentes en la GAM. Para identificar estas áreas se utilizó el método del reconocimiento remoto, el cual consiste en conocer la apariencia de un determinado cultivo en imágenes aéreas que permiten ubicar todas las áreas con aspecto similar y así identificar la adecuada diferenciación entre cultivos y usos. La información geográfica fue procesada mediante el programa de cómputo ArgGIS 9.2, el cual permitió obtener un mapa base a escala 1:12.500. El ha sido previamente desarrollada por diferentes instituciones del país, lo que permitió caracterizar la actividad agrícola de la GAM. Los resultados muestran que la actividad agrícola cubre alrededor del 24% del área total de la GAM, destacándose la producción de hortalizas, café y plantas ornamentales bajo sarán. Las hortalizas tienen la mayor importancia en extensión, ya que abarca el 52% del área agrícola de la GAM, seguidas del café con 44%, mientras que la producción de ornamentales bajo sarán representa solamente cerca del 4%. Al analizar los cambios ocurridos en la actividad agrícola de la GAM en los últimos 28 años, en el caso del café el área de producción disminuyó en 3569 ha, lo cual corresponde al 17% de las 22 545 ha identificadas en 1983.

CryoSat Level1b SAR/SARin: quality improvements towards BaselineC

Science.gov (United States)

Scagliola, Michele; Fornari, Marco; Bouzinac, Catherine; Tagliani, Nicolas; Parrinello, Tommaso

2014-05-01

CryoSat was launched on the 8th April 2010 and it is the first European ice mission dedicated to monitoring precise changes in the thickness of polar ice sheets and floating sea ice over a 3-year period. Cryosat carries an innovative radar altimeter called the Synthetic Aperture Interferometric Altimeter (SIRAL), that transmits pulses at a high pulse repetition frequency thus making the received echoes phase coherent and suitable for azimuth processing. This allows to reach a significantly improved along track resolution with respect to traditional pulse-width limited altimeters. CryoSat is the first altimetry mission operating in SAR mode and continuous improvement in the Level1 Instrument Processing Facility (IPF1) are being identified, tested and validated in order to improve the quality of the Level1b products. Towards the release of the BaselineC of the CryoSat Level1b SAR/SARin products, that is expected during 2014, several improvements have been identified: • a datation bias of about -0.5195 ms will be corrected • a range bias of about -0.6730 m will be corrected • the waveform length in the Level1b product will be doubled with respect to BaselineB • improved processing for 1Hz echoes to have sharper waveforms • surface sample stack weighting to filter out the single look echoes acquired at highest look angle, that results in a sharpening of the 20Hz waveforms This poster details the main improvements that are foreseen to be included in the CryoSat Level1b SAR/SARin products in BaselineC.

CO{sub 2} direct cycles suitable for AGR type reactors; Cycles directs de gaz carbonique applicables aux reacteurs du genre AGR

Energy Technology Data Exchange (ETDEWEB)

Maillet, E [Commissariat a l' Energie Atomique. Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

1967-10-01

The perspectives given by the gas turbines under pressure, to build simple nuclear power plants and acieving significantly high yield, are specified. The CO{sub 2} is characterised by by good efficiency under moderate temperature (500 to 750 Celsius degrees), compactness and the simpleness of machines and the safe exploitation (supply, storage, relief cooling, thermosyphon). The revision of thermal properties of the CO{sub 2} and loss elements show that several direct cycles would fit in particular to the AGR type reactors. Cycles that would diverge a little from classical models and able to lead to power and heat generation can lead by simple means to the best results. Several satisfying solutions present for the starting up, the power regulation and the stopping. The nuclear power plant components and the functioning safety are equally considered in the present report. The conclusions stimulate the studies and realizations of carbon dioxide gas turbines in when approprite. [French] Les perspectives offertes par la turbine a gaz sous pression, pour construire des centrales nucleaires simples et de rendement progressivement eleve, se precisent actuellement. le CO{sub 2} se distingue par sa bonne efficacite a temperature moderee (500 a 750 degres celsius), la compacite et la simplicite des machines, et la surete qu'il apporte a l'exploitation ( approvisionnement, stockage, refroidissement de secours, thermosiphon). La revision des proprietes thermophysiques du CO{sub 2} et des elements de pertes montre que divers cycles directs conviendraient en particulier aux reacteurs agr ou derives. Des cycles s'ecartant peu des modeles classiques, et se pretant ulterieurement a la production simultanee d'electricite et de chaleur, peuvent conduire par des moyens simples aux meilleurs resultats d'ensemble. Plusieurs solutions satisfaisantes se presentent pour le demarrage, le reglage de la puissance et l'arret. Les composants de la centrale et la surete de fonctionnement sont

Programmatic Baseline Summary for Phase 1 Privatization for the Tank Farm contractor

International Nuclear Information System (INIS)

DIEDIKER, J.A.

2000-01-01

The document describes the systematic integrated baseline planning process and provides a summary of the Tank Farm Contractor scope, schedule and cost analysis developed in support of the Phase 1 privatization mission

Programmatic Baseline Summary for Phase 1 Privatization for the Tank Farm contractor

Energy Technology Data Exchange (ETDEWEB)

DIEDIKER, J.A.

2000-04-22

The document describes the systematic integrated baseline planning process and provides a summary of the Tank Farm Contractor scope, schedule and cost analysis developed in support of the Phase 1 privatization mission.

ALARA trademark 1146 strippable coating

International Nuclear Information System (INIS)

Fricke, V.

1999-01-01

Strippable or temporary coatings are innovative technologies for decontamination that effectively reduce loose contamination at low cost. These coatings have become a viable option during the deactivation and decommissioning of both US Department of Energy (DOE) and commercial nuclear facilities to remove or fix loose contamination on both vertical and horizontal surfaces. The ALARA trademark 1146 strippable coating was demonstrated as part of the Savannah River Site LSDDP and successfully removed transferable (surface) contamination from multiple surfaces (metal and concrete) with an average decontamination factor for alpha contamination of 6.68 and an average percentage of alpha contamination removed of 85.0%. Beta contamination removed was an average DF of 5.55 and an average percentage removed of 82.0%. This paper is an Innovative Technology Summary Report designed to provide potential users with the information they need to quickly determine if a technology would apply to a particular environmental management problem. They also are designed for readers who may recommend that a technology be considered by prospective users. This Innovative Technology offers a 35% cost savings over the Baseline Technology

48 CFR 352.234-1 - Notice of earned value management system-pre-award Integrated Baseline Review.

Science.gov (United States)

2010-10-01

... 48 Federal Acquisition Regulations System 4 2010-10-01 2010-10-01 false Notice of earned value management system-pre-award Integrated Baseline Review. 352.234-1 Section 352.234-1 Federal Acquisition... provision: Notice of Earned Value Management System—Pre-Award Integrated Baseline Review (October 2008) The...

Pioneiros da ecologia política agrária contemporânea The pioneers of the contemporary agrarian political ecology

Directory of Open Access Journals (Sweden)

Humberto Miranda Nascimento

2009-12-01

Full Text Available O presente artigo tem por objetivo apresentar os pioneiros dos estudos materialistas sobre ecologia política agrária contemporânea. É feita uma análise das contribuições da Escola Russa de Estudos do Solo e de referências mais recentes aos escritos de Marx e Liebig. Nas considerações finais, enfatiza-se a necessidade de desenvolver a abordagem da Ecologia Política Agrária como maneira mais apropriada de entender a relação entre sistemas agrários, formações sociais e ecossistemas específicos em áreas rurais.The pioneering studies on the relationship between society and nature are important for the analysis of agricultural and ecological changes in rural areas. The goal of the present article is to introduce the contemporary pioneers of the agrarian ecology studies with a Marxist Materialism approach. The agrarian ecology describes the relations among agrarian systems, social formations and specific ecosystems in rural territories. Thence, the concept has a double function: turn the agrarian problem into an ecological theme and redefine its importance for the current studies on rural territory.

The chemical stability of TRISO-coated HTGR fuel. Pt. 1. Status report

International Nuclear Information System (INIS)

Groot, P.; Cordfunke, E.H.P.; Konings, R.J.M.

1994-12-01

The US fuel seemed to be more difficult to produce than the German fuel. Also the chemical stability of this fuel must be investigated. The conditions are more severe in the US concept than in the German concept. Oxidation of the graphite seems to be no problem, according to US HTGR concept. A ZrC coating seems to have a number of advantages with regard to the SiC coating: (1) Better retention, (2) no reaction with Pd, (3) no thermal dissociation. Only the oxidation resistance is worse than SiC. Also the maximum stress must be determined that the ZrC coating can have. (orig./HP)

PRAPRAG: software para planejamento racional de máquinas agrícolas PRAPRAG: software for rational planning of agricultural machines

OpenAIRE

Erivelto Mercante; Eduardo G. de Souza; Jerry A Johann; Antonio Gabriel Filho; Miguel A Uribe-Opazo

2010-01-01

O software PRAPRAG é uma ferramenta de escolha de máquinas e implementos agrícolas que apresentam o menor custo por área ou por quantidade produzida, bem como, faz o planejamento de aquisição das máquinas para a propriedade agrícola, do ponto de vista técnico e econômico. Foi utilizada a linguagem de programação Borland Delphi 3.0 e, a partir de prospectos das máquinas e implementos, criou-se um banco de dados onde o usuário pode cadastrar e modificar suas características de uso. O software m...

Color stability of esthetic coatings applied to nickel-titanium archwires

Directory of Open Access Journals (Sweden)

Marcus Vinicius Neiva Nunes do REGO

Full Text Available Abstract Introduction Color stability is an important feature to be considered when using esthetic coated archwires. Objective To evaluate color changes on the surface of esthetic nickel-titanium archwires coated with Teflon (Ortho Organizers, USA or epoxy resin (Tecnident, Brazil after immersion in staining solution. Material and method Twelve 20-mm-long wire segments were used for each type of coating, which were mounted as two test specimens with a width of 7 mm each. The buccal surface of the archwires was evaluated for fluorescence and color measurements both at baseline and after immersion in a staining solution for 21 days using the VITA Easyshade® Compact spectrophotometer (Model DEASYC220. Differences in total color change according to coating type were compared using an independent samples t-test (p<0.05. The surface characteristics of as-received coated archwires were assessed using scanning electron microscopy. Result Color changes were observed on the esthetic coatings, with a significant difference between the two brands analyzed. Surface analysis revealed flaws such as wear, pitting, elevations, lack of material, granulation, grooves, cracks, and lack of standardization in the coating process in all as-received archwires, but flaws were less evident in epoxy-resin coatings. Conclusion The two esthetic coatings did not show color stability, but Teflon coatings showed a more intense color change than epoxy-resin coatings.

Migración internacional, actividades agrícolas y distribución del ingreso en una comunidad oaxaqueña, México

OpenAIRE

Renato Salas Alfaro

2012-01-01

Este trabajo explora el efecto que tiene la migración internacional y las remesas sobre las actividades agrícolas y la distribución del ingreso en una comunidad indígena que recientemente ha masificado su migración internacional. Se emplearon modelos para relacionar variables agrícolas contra factores productivos, socio demográficos y de financiamiento a la migración en el hogar, asimismo, la descomposición del coeficiente de Gini se utilizó para determinar el efecto que tienen las fuentes de...

Self-healing atmospheric plasma sprayed Mn1.0Co1.9Fe0.1O4 protective interconnector coatings for solid oxide fuel cells

Science.gov (United States)

Grünwald, Nikolas; Sebold, Doris; Sohn, Yoo Jung; Menzler, Norbert Heribert; Vaßen, Robert

2017-09-01

Dense coatings on metallic interconnectors are necessary to suppress chromium poisoning of SOFC cathodes. Atmospherically plasma sprayed (APS) Mn1.0Co1.9Fe0.1O4 (MCF) protective layers demonstrated reduced chromium related degradation in laboratory and stack tests. Previous analyses revealed strong microstructural changes comparing the coating's as-sprayed and operated condition. This work concentrates on the layer-densification and crack-healing observed by annealing APS-MCF in air, which simulates the cathode operation conditions. The effect is described by a volume expansion induced by a phase transformation. Reducing conditions during the spray process lead to a deposition of the MCF in a metastable rock salt configuration. Annealing in air activates diffusion processes for a phase transformation to the low temperature stable spinel phase (T coating. The process decelerates when the cracks are closed, as the gas route is blocked and further oxidation continues over solid state diffusion. The self-healing abilities of metastable APS coatings could be interesting for other applications.

Use of Coatings on Hydraulic Steel Structures: Part 1-Overview and Field Survey

Science.gov (United States)

2016-09-01

stripped out the coating. • On a gate, a contractor didn’t follow the specifications in the area of the rivets, leading to premature failure of...the coating. • On another gate, where polyurea was applied, the contractor missed the recoat window and unfortunately, the contractor was not forced...epaact1992controlofvocemissionsdistributionregssi374of1997. ht ml. Jackson, Joshua E. 2016. “Cost of Corrosion Annually in the U.S. Over $1.1 Trillion in

Stack Characterization in CryoSat Level1b SAR/SARin Baseline C

Science.gov (United States)

Scagliola, Michele; Fornari, Marco; Di Giacinto, Andrea; Bouffard, Jerome; Féménias, Pierre; Parrinello, Tommaso

2015-04-01

CryoSat was launched on the 8th April 2010 and is the first European ice mission dedicated to the monitoring of precise changes in the thickness of polar ice sheets and floating sea ice. CryoSat is the first altimetry mission operating in SAR mode and it carries an innovative radar altimeter called the Synthetic Aperture Interferometric Altimeter (SIRAL), that transmits pulses at a high pulse repetition frequency thus making the received echoes phase coherent and suitable for azimuth processing. The current CryoSat IPF (Instrument Processing Facility), Baseline B, was released in operation in February 2012. After more than 2 years of development, the release in operations of the Baseline C is expected in the first half of 2015. It is worth recalling here that the CryoSat SAR/SARin IPF1 generates 20Hz waveforms in correspondence of an approximately equally spaced set of ground locations on the Earth surface, i.e. surface samples, and that a surface sample gathers a collection of single-look echoes coming from the processed bursts during the time of visibility. Thus, for a given surface sample, the stack can be defined as the collection of all the single-look echoes pointing to the current surface sample, after applying all the necessary range corrections. The L1B product contains the power average of all the single-look echoes in the stack: the multi-looked L1B waveform. This reduces the data volume, while removing some information contained in the single looks, useful for characterizing the surface and modelling the L1B waveform. To recover such information, a set of parameters has been added to the L1B product: the stack characterization or beam behaviour parameters. The stack characterization, already included in previous Baselines, has been reviewed and expanded in Baseline C. This poster describes all the stack characterization parameters, detailing what they represent and how they have been computed. In details, such parameters can be summarized in: - Stack

Pickering NGS A reactor building 1 dome refurbishment long-term monitoring of coating

International Nuclear Information System (INIS)

Deans, J.J.; Chan, P.; Gomme, R.

2006-01-01

'Full text:' To reduce air leakage through the dome of Pickering NGS A Reactor Building 1, in August 1993 a portion of the exterior concrete surface was coated with a single component elastomeric polyurethane material. An internal positive pressure test of the building, conducted between November 5 and 7, 1993, found that the air leakage rates were significantly lower in this test than leakage rates which had been measured during a pressure test conducted in 1992. This reduction in leakage was attributed to the successful performance of the coating. The need for a high-performance, elastomeric surface coating was identified for reduction of air leakage levels through the dome of Reactor Building l of Ontario Power Generation's (formerly Ontario Hydro's) Pickering 'A' Nuclear Generating Station near Toronto. A number of candidate coatings were extensively tested to assess the performance characteristics and identify a material that could withstand the elements and perform effectively for around 20 years. Under normal operating conditions, a licensing limit of 2.7% of contained mass/hour is set for permissible containment leakage whilst the operational working target is less than 1%. The facility's engineers determined that any leakages were pressure-dependent, so in an effort to remain well within their working target, they sought a system that would bridge and seal any hairline cracks in the concrete dome and thereby prevent the passage of gas or vapour through the substrate. On the basis of scheduling and cost, they concluded that a high performance coating was most appropriate for the project, and hired Kinectrics (formerly Ontario Hydro Technologies (OHT)) to select, test, assess and arrange for the application to the RB 1 Dome. In all, nearly 70 separate manufacturers were approached by Kinectrics with a view to obtaining recommendations for treatment. The respective performance data of the respondents' products were compared with a set of specific design

Indicadores para estimar la sostenibilidad agrícola de la cuenca media del río Reventado, Cartago, Costa Rica

Directory of Open Access Journals (Sweden)

Laura Ramírez

2008-01-01

Full Text Available El objetivo de este trabajo fue identificar indicadores para evaluar la sostenibilidad agrícola en la cuenca media del río Reventado. Se encontró una acumulación Ca, Mg y K en los terrenos y una disminución del porcentaje de saturación de acidez con los años de uso del suelo en agricultura, los suelos han mejorado su fertilidad con el tiempo por efecto antrópico. Se encontró una tendencia similar con el P disponible, cuyos niveles aumentaron en ≈2,3 mg.l-1.año-1, eventualmente podría reducirse la aplicación de este elemento, lo que haría más sostenible el sistema de producción. Los niveles de erosión, en la mayoría de las fincas, fueron moderados; el grosor del horizonte A y el P disponible disminuyeron al pasar de erosión leve, a moderada y a severa. El índice estructural y la capacidad de uso de las tierras indicaron en las Clases II y III, suelos moderadamente susceptibles a ser degradados, y en las clases mayores alta susceptibilidad a ser degradados. No se encontró diferencias significativas entre las clases de capacidad de uso de la tierra y la producción de los cultivos. La producción de papa y cebolla fue mayor en zonas con riego, donde la relación B/C mayor se encontró en Tierra Blanca, debido al manejo del sistema productivo. Los indicadores económicos y sociales evaluados fueron positivos para ambas regiones, no así los indicadores ambientales. La actividad agrícola aún se mantiene como una actividad rentable para los productores de la cuenca media del río Reventadoactividad agrícola aún se mantiene como una actividad rentable para los productores de la cuenca media del río Reventado.

Mixed Waste Focus Area integrated technical baseline report, Phase 1: Volume 1

International Nuclear Information System (INIS)

1996-01-01

The Department of Energy (DOE) established the Mixed Waste Characterization, Treatment, and Disposal Focus Area (MWFA) to develop and facilitate implementation of technologies required to meet the Department's commitments for treatment of mixed low-level and transuranic wastes. The mission of the MWFA is to provide acceptable treatment systems, developed in partnership with users and with participation of stakeholders, tribal governments, and regulators, that are capable of treating DOE's mixed waste. These treatment systems include all necessary steps such as characterization, pretreatment, and disposal. To accomplish this mission, a technical baseline is being established that forms the basis for determining which technology development activities will be supported by the MWFA. The technical baseline is the prioritized list of deficiencies, and the resulting technology development activities needed to overcome these deficiencies. This document presents Phase I of the technical baseline development process, which resulted in the prioritized list of deficiencies that the MWFA will address. A summary of the data and the assumptions upon which this work was based is included, as well as information concerning the DOE Office of Environmental Management (EM) mixed waste technology development needs. The next phase in the technical baseline development process, Phase II, will result in the identification of technology development activities that will be conducted through the MWFA to resolve the identified deficiencies

Escenarios de erosión bajo diferentes manejos agrícolas en la cuenca del lago de Zirahuén, Michoacán, México

Directory of Open Access Journals (Sweden)

Manuel E. Mendoza Cantú

2009-10-01

Full Text Available La erosión hídrica, la desecación y pérdida de áreas y volúmenes de los lagos son problemas severos en las cuencas cerradas del Sistema Volcánico Transversal. Este deterioro comienza a extenderse a la cuenca del lago de Zirahuén, Michoacán, en la cual se encuentra uno de los pocos lagos mexicanos de aguas casi prístinas; por ello, es urgente plantear estudios que ofrezcan bases para un manejo sostenible de los recursos naturales que beneficie a los distintos usuarios del lago y de la cuenca. El objetivo de este trabajo fue predecir la erosión hídrica asociada a sistemas de manejo agrícola considerando tres tipos de labranza (tradicional, mínima y de conservación en la cuenca del lago de Zirahuén. La predicción se realizó aplicando la Ecuación Universal de Pérdidas de Suelo (EUPS dentro del contexto de un sistema de información geográfica. Los resultados indicaron que el uso de la labranza de conservación en las áreas agrícolas de la cuenca, reduciría las pérdidas de suelo a menos de 3 t ha-1 año-1 en toda el área agrícola de la cuenca, y probablemente se disminuiría la contaminación por arrastre de sedimentos en el lago de Zirahuén.

Antropometria aplicada aos operadores de tratores agrícolas Anthropometrics applied to the agricultural tractors operators

Directory of Open Access Journals (Sweden)

José Fernando Schlosser

2002-12-01

Full Text Available O objetivo deste trabalho foi determinar o padrão antropométrico dos operadores de tratores agrícolas da Depressão Central do Rio Grande do Sul. Os operadores de tratores agrícolas foram medidos por meio de um painel constituído por duas chapas metálicas, permanecendo durante as medições em pé, eretos, com o mínimo de roupa possível e em contato com o painel. As variáveis medidas foram as seguintes: altura do corpo; altura ao nível dos olhos; altura ao nível dos olhos sentado; altura do cotovelo; alcance do braço; alcance da mão; distância pé-patela; apoio do assento. Os dados obtidos demonstram que há diferenças entre o biótipo do operador utilizado pela indústria de tratores agrícolas e o do operador da região, de forma que este último apresentou, para todas as medidas, à exceção do apoio do assento, uma média maior. Observa-se também que, para cada medida, os limites inferior e superior do intervalo onde se encontram 90% dos operadores avaliados foram, respectivamente, menores e maiores que o padrão utilizado pela indústria, caracterizando uma maior variação. Levando-se em consideração as diferenças existentes entre o perfil antropométrico dos operadores de tratores agrícolas da Depressão Central do Rio Grande do Sul e os parâmetros utilizados pela indústria, pode-se confirmar a hipótese de que os tratores agrícolas que se encontram atualmente em comercialização no Brasil podem não oferecer o conforto necessário ao operador desta região .The objective of this work was to evaluate the anthropometric measures of the agricultural tractor operators of the Central Region of Rio Grande do Sul State. The agricultural tractor operators were measured through a panel that was made of two metallic plates. During the measurement, they were standing, wearing the minimum amount clothes possible, and touching the panel. The measures body height, eyes level height (standing, eyes level height (sitting, elbow

NECL1 coated PLGA as favorable conduits for repair of injured peripheral nerve

International Nuclear Information System (INIS)

Xu, Fuben; Zhang, Kun; Lv, Peizhen; Lu, Rongbin; Zheng, Li; Zhao, Jinmin

2017-01-01

Restoration of normal neurological function of transected peripheral nerve challenged regenerative medicine and surgery. Previous studies showed that Nectin-like molecule 1 (NECL1) is one of the important adhesion molecules on the axons and Schwann cells is located along the internodes in direct apposition to NECL1. In this study, we fabricated PLGA membrane pre-coated with NECL1, mimicking the natural axons to enhance the adhesion of Schwann cells. Investigation of the cellular response in vitro was performed by detecting cytotoxicity, proliferation, morphology, viability, specific markers and Scanning Electron Microscopy (SEM) of Schwann cells cultured in PLGA. Further, the NECL1-coated PLGA conduits were used for peripheral nerve repair after sciatic nerve defect was constructed. Results showed that PLGA-coated NECL1 enhanced cell proliferation compared with PLGA, as evidenced by MTT analysis, cell viability assay and histological evaluation. RT-PCR results showed that GDNF (glial cell line-derived neurotrophic factor), BDNF (brain-derived neurotrophic factor), CNTF (ciliary neurotrophic factor) and neurotrophic factors of axonal regeneration were highly expressed in PLGA/NECL1 group. S100, which is Schwann cell marker, was also elevated in PLGA-NCEL1 in both mRNA and protein expression as demonstrated by PCR and immunohistochemical examination. Moreover, in vivo study showed that implantation of PLGA/NCEL1 tubes in bridging the nerve defect can significantly improve Schwann cell aggregation and attachment and greatly enhance the functional recovery of nerve regeneration as compared with control and PLGA groups. Therefore, the novel blend of PLGA/NECL1 conduits proved to be promising candidate for tissue engineering scaffold. - Highlights: • A fabricated PLGA tubes pre-coated with Nectin-like molecule 1 (NECL1) strategy for sciatic nerve regeneration is proposed. • The NECL1 coated PLGA can promote Schwann cells adhesion and growth meanwhile maintain the

Mecanización agrícola ¿Deterioro o conservación del suelo?

Directory of Open Access Journals (Sweden)

Armando Alvarado Chaves

2006-05-01

Full Text Available “Mecanización agrícola; ¿Deterioro o conservación del suelo?” trata sobre el mito de que la mecanización o preparación de los suelos, en forma mecánica, es el detonante del deterioro de los suelos por erosión sobre todo por erosión hídrica y en menor grado por erosión eólica. La erosión de los suelos puede ser de poca o de gran magnitud, dependiendo de cuatro factores, los cuales se analizan como errores que se cometen en el momento de preparar los suelos. Estos errores son, en realidad, los causantes del deterioro de los suelos por erosión y no la mecanización, ya que esta, bien planificada y aplicada, puede incluso servir para la conservaciónde los suelos y el medio ambiente. También se describen los implementos agrícolas que pueden usarse para reducir la erosión de los suelos, citando su forma de trabajo y algunas de las ventajas del uso de esos implementos.

Heparin-coated cardiopulmonary bypass circuits selectively deplete the pattern recognition molecule ficolin-2 of the lectin complement pathway in vivo

DEFF Research Database (Denmark)

Hein, Estrid; Munthe-Fog, L; Thiara, A S

2015-01-01

of infections. Thus, we investigated the biocompatibility of the recognition molecules of the lectin pathway in two different types of cardiopulmonary bypass circuits. Bloods were drawn at five time-points before, during and postoperatively from 30 patients undergoing elective cardiac surgery. Patients were...... randomized into two groups using different coatings of cardiopulmonary bypass circuits, Phisio® (phosphorylcholine polymer coating) and Bioline® (albumin-heparin coating). Concentrations of MBL, ficolin-1, -2 and -3 and soluble C3a and terminal complement complex (TCC) in plasma samples were measured......-2 was depleted from plasma during cardiac surgery when using heparin-coated bypass circuits and did not reach baseline level 24 h postoperation. These findings may have implications for the postoperative susceptibility to infections in patients undergoing extracorporeal circulation procedures....

Heysham II/Torness AGR steam generator

International Nuclear Information System (INIS)

Charcharos, A.N.; Wood, M.B.; Glasgow, J.R.

1988-01-01

The AGR Steam Generators for Heysham II and Torness Power Stations have been installed at site and are being operated in the initial low temperature commissioning plant engineering tests. In this paper a description of the high pressure once-through steam generators together with layout arrangements, materials employed, operating parameters, plant operating conditions and constraints is given. An outline of the development of the design through thermo-hydraulic considerations, mechanical design, instrumentation to component testing is presented. Special features of the design directed to accommodate such requirements as seismic loadings, waterside static and dynamic stability, gas flow induced vibration, thermal expansions are described in detail. The fabrication facilities employed and techniques selected and developed for the manufacture and assembly of the heating surfaces are presented. These include welding processes, tube manipulation and heat treatment with details of the automation applied to the processes. Operating experience in the early commissioning plant engineering tests at Site is described with an emphasis on those tests which provide the final confirmation of the design prior to operation at full load. The paper concludes with a description of the outstanding commissioning activities up to raise power. (author)

Heysham II/Torness AGR steam generator

Energy Technology Data Exchange (ETDEWEB)

Charcharos, A N [National Nuclear Corporation Ltd., Knutsford (United Kingdom); Wood, M B; Glasgow, J R [NEI Power Projects Ltd., Gateshead (United Kingdom)

1988-07-01

The AGR Steam Generators for Heysham II and Torness Power Stations have been installed at site and are being operated in the initial low temperature commissioning plant engineering tests. In this paper a description of the high pressure once-through steam generators together with layout arrangements, materials employed, operating parameters, plant operating conditions and constraints is given. An outline of the development of the design through thermo-hydraulic considerations, mechanical design, instrumentation to component testing is presented. Special features of the design directed to accommodate such requirements as seismic loadings, waterside static and dynamic stability, gas flow induced vibration, thermal expansions are described in detail. The fabrication facilities employed and techniques selected and developed for the manufacture and assembly of the heating surfaces are presented. These include welding processes, tube manipulation and heat treatment with details of the automation applied to the processes. Operating experience in the early commissioning plant engineering tests at Site is described with an emphasis on those tests which provide the final confirmation of the design prior to operation at full load. The paper concludes with a description of the outstanding commissioning activities up to raise power. (author)

Utilities and offsites design baseline. Outside Battery Limits Facility 6000 tpd SRC-I Demonstration Plant. Volume 1

Energy Technology Data Exchange (ETDEWEB)

None

1984-05-25

As part of the overall Solvent Refined Coal (SRC-1) project baseline being prepared by International Coal Refining Company (ICRC), the RUST Engineering Company is providing necessary input for the Outside Battery Limits (OSBL) Facilities. The project baseline is comprised of: design baseline - technical definition of work; schedule baseline - detailed and management level 1 schedules; and cost baseline - estimates and cost/manpower plan. The design baseline (technical definition) for the OSBL Facilities has been completed and is presented in Volumes I, II, III, IV, V and VI. The OSBL technical definition is based on, and compatible with, the ICRC defined statement of work, design basis memorandum, master project procedures, process and mechanical design criteria, and baseline guidance documents. The design basis memorandum is included in Paragraph 1.3 of Volume I. The baseline design data is presented in 6 volumes. Volume I contains the introduction section and utility systems data through steam and feedwater. Volume II continues with utility systems data through fuel system, and contains the interconnecting systems and utility system integration information. Volume III contains the offsites data through water and waste treatment. Volume IV continues with offsites data, including site development and buildings, and contains raw materials and product handling and storage information. Volume V contains wastewater treatment and solid wastes landfill systems developed by Catalytic, Inc. to supplement the information contained in Volume III. Volume VI contains proprietary information of Resources Conservation Company related to the evaporator/crystallizer system of the wastewater treatment area.

The agr inhibitors solonamide B and analogues alter immune responses to Staphylococccus aureus but do not exhibit adverse effects on immune cell functions

DEFF Research Database (Denmark)

Baldry, Mara; Kitir, Betül; Frøkiær, Hanne

2016-01-01

Staphylococcus aureus infections are becoming increasingly difficult to treat due to antibiotic resistance with the community-associated methicillin-resistant S. aureus (CA-MRSA) strains such as USA300 being of particular concern. The inhibition of bacterial virulence has been proposed as an alte......Staphylococcus aureus infections are becoming increasingly difficult to treat due to antibiotic resistance with the community-associated methicillin-resistant S. aureus (CA-MRSA) strains such as USA300 being of particular concern. The inhibition of bacterial virulence has been proposed...... as an alternative approach to treat multi-drug resistant pathogens. One interesting anti-virulence target is the agr quorum-sensing system, which regulates virulence of CA-MRSA in response to agr-encoded autoinducing peptides. Agr regulation confines exotoxin production to the stationary growth phase...

Determinación de la adsorción de cadmio mediante isotermas de adsorción en suelos agrícolas venezolanos

OpenAIRE

Subero Neudis; Sánchez Nereida; Rivero Carmen

2011-01-01

El cadmio es un metal pesado que tiende a acumularse en la superficie del suelo. En los últimos años, las actividades antropogénicas han ocasionado un incremento en los niveles de este metal en suelos agrícolas generando gran preocupación ambiental debido a su movilidad y lixiviación en el perfil del suelo y a la facilidad con que es absorbido por las plantas. El objetivo de este trabajo fue determinar la capacidad de adsorción de cadmio, de cuatro suelos venezolanos de uso agrícola con difer...

Large short-baseline νμ disappearance

International Nuclear Information System (INIS)

Giunti, Carlo; Laveder, Marco

2011-01-01

We analyze the LSND, KARMEN, and MiniBooNE data on short-baseline ν μ →ν e oscillations and the data on short-baseline ν e disappearance obtained in the Bugey-3 and CHOOZ reactor experiments in the framework of 3+1 antineutrino mixing, taking into account the MINOS observation of long-baseline ν μ disappearance and the KamLAND observation of very-long-baseline ν e disappearance. We show that the fit of the data implies that the short-baseline disappearance of ν μ is relatively large. We obtain a prediction of an effective amplitude sin 2 2θ μμ > or approx. 0.1 for short-baseline ν μ disappearance generated by 0.2 2 2 , which could be measured in future experiments.

Propuesta metodológica interdisciplinaria para el análisis de las relaciones comerciales presentes en el sector agrícola costarricense: el caso del subsector frijolero

Directory of Open Access Journals (Sweden)

Ileana Ávalos

2011-01-01

Full Text Available El complejo entramado de relaciones de poder genera influencia directa en la construcción de políticas públicas agrícolas y en los procesos de intercambio comercial. En un sector tan sensible como el agrícola, cobra mayor relevancia el reconocimiento, identificación y análisis de las relaciones que se estructuran tanto a nivel sectorial como sub-sectorial. Esta disección es la que podría permitir el planteamiento de renovadas políticas públicas y de estrategias asertivas para el sector agrícola. El presente artículo es producto de una investigación científica denominada ?Dinámica de poder en la agrocadena costarricense de frijol: un estudio a partir del Sello de Apoyo al productor nacional de frijol?, la cual describe las relaciones existentes entre grupos económicos, comerciales y sociales dentro de la agrocadena del frijol. Particularmente este artículo realiza una propuesta metodológica para analizar las relaciones de poder en el sector agrícola, tomando como referencia la experiencia adquirida analizando el subsector frijolero costarricense.

Relações contratuais de crédito agrícola e o papel dos agentes financeiros privados: teoria e evidências dos EUA

Directory of Open Access Journals (Sweden)

Fabio R Chaddad

2003-01-01

Full Text Available Este trabalho analisa a questão do financiamento da produção agrícola sob uma ótica sistêmica, considerando o papel dos agentes privados no fornecimento de crédito rural. Desenvolve-se a idéia de que o volume e o custo de recursos financeiros disponibilizados para a produção agrícola são afetados por "fricções" em diversas transações sequenciais interligando emprestadores e tomadores de crédito. O objetivo do trabalho é analisar as vantagens comparativas dos diversos agentes que atuam no mercado de crédito, enfocando o potencial de cada agente em reduzir as tais fricções. Esta análise comparativa baseia-se na leitura do funcionamento do mercado de crédito agrícola dos Estados Unidos e pode ser aplicada nara o desenvolvimento de novos arranjos contratuais no mercado brasileiro.

Characteristics and corrosion studies of vanadate conversion coating formed on Mg–14 wt%Li–1 wt%Al–0.1 wt%Ce alloy

International Nuclear Information System (INIS)

Ma Yibin; Li Ning; Li Deyu; Zhang Milin; Huang Xiaomei

2012-01-01

Highlights: ► Vanadate film forms on the surface of Mg–Li–Al–Ce alloy. ► Vanadate coating improves the corrosion resistance. ► Vanadate coating is composed of Mg(OH) 2 , Li 2 O and V 2 O 5 . - Abstract: Mg–14Li–1Al–0.1Ce alloy is immersed in NH 4 VO 3 + K 3 (Fe(CN) 6 ) solutions with different NH 4 VO 3 and/or K 3 (Fe(CN) 6 ) concentrations, and different immersion time. The surface morphology and composition of the vanadate coating are then characterized by scanning electron microscopy with energy dispersion spectroscopy (SEM-EDS) and X-ray photoelectron spectroscopy (XPS), and the corrosion behavior of the conversion coating is studied by polarization technique and electrochemical impedance spectroscopy (EIS). The experimental results indicate that the vanadate film with better corrosion resistance forms on Mg–Li–Al–Ce surface after the sample is immersed in 30 g L −1 NH 4 VO 3 + 3.75 g L −1 K 3 (Fe(CN) 6 ) solution at 80 °C for 10 min. The coating consists of V 2 O 5 , Li 2 O and Mg(OH) 2 .

Microstructure and Properties of the Interface Area in the Laser Cladded Ni Based Coatings on the 1Cr10Mo1NiWVNbN Steel

Directory of Open Access Journals (Sweden)

Yunxia Chen

2017-05-01

Full Text Available The Ni-based coatings were deposited on the 1Cr10Mo1NiWVNbN steel by using laser cladding process. The microstructure and properties of the coatings interface area were investigated by OM (Optical Microscopy, SEM (Scanning Electron Microscope, XRD (X-Ray Diffraction microhardness test and EDS (Energy Spectrum Analysis analysis. The results show that the bonding condition of the coatings interface is different in the monolayer and the trilayer. The monolayer coatings have a small dilution area. The dilution rate in a coating layer increases by layers. The scale of ferrite (α phase increases with the layer increases. The surface cladding quality of a monolayer is better than that of the trilayer coatings. The width of the interface increases with the increase of the layer. The width of the interface region in the trilayer coatings increases significantly. The microhardness of the interface zone is much higher than that in the coatings zone and the substrate zone. The microhardness of trilayer coatings is higher than that of the monolayer.

Modelo Evolucionário de Aprendizado Agrícola

Directory of Open Access Journals (Sweden)

José Maria Ferreira da Silveira

2011-11-01

Full Text Available The definition of the agriculture sector as a supplier dominated is a very restrictive supposition which implies that the technological changes would be residual. The learning process of the farmer throughout, determines the increase in productivity, and simultaneously the reduction in the cost of production, which all depends on the ability of the producers to recognize the value of new information, as well as the managerial ability to apply technological knowledge. The investments in the managerial capability of the farmers allow taking better advantage of the external knowledge. With the aim of systemizing the chains of the main ideas on agricultural dynamics, one has sought to construct the Evolutionary Model of Learning. Preliminary results showed that innovative producers on average maintain an avant-garde technological stance. The increase in the absorptive capacity serves to conquer gains in production and to make lower costs.A definição do setor agrícola como sendo dominado pelos fornecedores é uma pressuposição muito restritiva, já que define a mudança tecnológica como residual. O processo de aprendizado do agricultor no decorrer do tempo é responsável pelo aumento da produtividade e, paralelamente, pela redução dos custos de produção, dependendo da capacidade do produtor de interpretar e assimilar as novas informações, bem como da habilidade gerencial do uso do conhecimento tecnológico. Os investimentos na capacidade gerencial dos agricultores possibilitam um melhor aproveitamento do conhecimento externo. No intuito de sistematizar o encadeamento das principais ideias da dinâmica agrícola, buscou-se construir o modelo evolucionário de aprendizado. Os resultados preliminares mostraram que os produtores inovadores, em média, mantêm posições de vanguarda tecnológica. O aumento da capacidade de absorção auxilia nos ganhos produtivos e nas quedas dos custos.

A study of TaxC1-x coatings deposited on biomedical 316L stainless steel by radio-frequency magnetron sputtering

International Nuclear Information System (INIS)

Ding, M.H.; Wang, B.L.; Li, L.; Zheng, Y.F.

2010-01-01

In this paper, Ta x C 1-x coatings were deposited on 316L stainless steel (316L SS) by radio-frequency (RF) magnetron sputtering at various substrate temperatures (T s ) in order to improve its corrosion resistance and hemocompatibility. XRD results indicated that T s could significantly change the microstructure of Ta x C 1-x coatings. When T s was x C 1-x coatings were in amorphous condition, whereas when T s was ≥150 deg. C, TaC phase was formed, exhibiting in the form of particulates with the crystallite sizes of about 15-25 nm (T s = 300 deg. C). Atomic force microscope (AFM) results showed that with the increase of T s , the root-mean-square (RMS) values of the Ta x C 1-x coatings decreased. The nano-indentation experiments indicated that the Ta x C 1-x coating deposited at 300 deg. C had a higher hardness and modulus. The scratch test results demonstrated that Ta x C 1-x coatings deposited above 150 deg. C exhibited good adhesion performance. Tribology tests results demonstrated that Ta x C 1-x coatings exhibited excellent wear resistance. The results of potentiodynamic polarization showed that the corrosion resistance of the 316L SS was improved significantly because of the deposited Ta x C 1-x coatings. The platelet adhesion test results indicated that the Ta x C 1-x coatings deposited at T s of 150 deg. C and 300 deg. C possessed better hemocompatibility than the coating deposited at T s of 25 deg. C. Additionally, the hemocompatibility of the Ta x C 1-x coating on the 316L SS was found to be influenced by its surface roughness, hydrophilicity and the surface energy.

Progress in Solving the Elusive Ag Transport Mechanism in TRISO Coated Particles: “What is new?”

International Nuclear Information System (INIS)

Rooyen, I.J. van; Petti, D.A.; Nabielek, H.; Neethling, J.H; Kania, M.J.

2014-01-01

The tristructural isotropic (TRISO) particle for a high temperature reactor (HTR) has been developed to an advanced state where the coating withstands internal gas pressures and retains nearly all fission products during irradiation and under postulated accidents. However, one exception is silver (Ag) that has been found to be released from high quality TRISO coated particles during irradiation and high temperature accident heating tests. Although out-of-pile laboratory tests have yet to elucidate the mechanism of transport of Ag through silicon carbide (SiC), effective diffusion coefficients have been derived to successfully reproduce measured "1"1"0"mAg- releases from irradiated HTR fuel elements, compacts and TRISO particles. It was found that Ag transport through SiC does not proceed via bulk volume diffusion. Presently grain boundary diffusion that may be irradiation enhanced either by neutron bombardment or by the presence of fission products such as palladium (Pd), are the two hypotheses that have been proposed. Recent studies of irradiated AGR-1 TRISO fuel using scanning transmission electron microscopy (STEM), transmission Kikuchi diffraction (TKD) patterns, and high resolution transmission electron microscopy (HRTEM) have been used to further the understanding of Ag transport through TRISO particles. No Ag was observed in SiC grains, but Ag was identified at triple-points and grain boundaries of the SiC layer in the TRISO particle. Cadmium (Cd) was also found in some of the very same triple junctions, but this could be related to silver behavior as "1"1"0"mAg decays to "1"1"0Cd or true Cd release as a fission product. Palladium was identified as the main constituent of micron-sized precipitates present at the SiC grain boundaries. The potential role of Pd in the transport of Ag will be discussed further. (author)

Tablet coating by injection molding technology - Optimization of coating formulation attributes and coating process parameters.

Science.gov (United States)

Desai, Parind M; Puri, Vibha; Brancazio, David; Halkude, Bhakti S; Hartman, Jeremy E; Wahane, Aniket V; Martinez, Alexander R; Jensen, Keith D; Harinath, Eranda; Braatz, Richard D; Chun, Jung-Hoon; Trout, Bernhardt L

2018-01-01

We developed and evaluated a solvent-free injection molding (IM) coating technology that could be suitable for continuous manufacturing via incorporation with IM tableting. Coating formulations (coating polymers and plasticizers) were prepared using hot-melt extrusion and screened via stress-strain analysis employing a universal testing machine. Selected coating formulations were studied for their melt flow characteristics. Tablets were coated using a vertical injection molding unit. Process parameters like softening temperature, injection pressure, and cooling temperature played a very important role in IM coating processing. IM coating employing polyethylene oxide (PEO) based formulations required sufficient room humidity (>30% RH) to avoid immediate cracks, whereas other formulations were insensitive to the room humidity. Tested formulations based on Eudrajit E PO and Kollicoat IR had unsuitable mechanical properties. Three coating formulations based on hydroxypropyl pea starch, PEO 1,000,000 and Opadry had favorable mechanical (35% elongation, >95×10 4 J/m 3 toughness) and melt flow (>0.4g/min) characteristics, that rendered acceptable IM coats. These three formulations increased the dissolution time by 10, 15 and 35min, respectively (75% drug release), compared to the uncoated tablets (15min). Coated tablets stored in several environmental conditions remained stable to cracking for the evaluated 8-week time period. Copyright © 2017 Elsevier B.V. All rights reserved.

Roll-coating fabrication of flexible large area small molecule solar cells with power conversion efficiency exceeding 1%

DEFF Research Database (Denmark)

Liu, Wenqing; Liu, Shiyong; Zawacka, Natalia Klaudia

2014-01-01

All solution-processed flexible large area small molecule bulk heterojunction solar cells were fabricated via roll-coating technology. Our devices were produced from slot-die coating on a lab-scale mini roll-coater under ambient conditions without the use of spin-coating or vacuum evaporation.......01%, combined with an open circuit voltage of 0.73 V, a short-circuit current density of 3.13 mA cm (2) and a fill factor of 44% were obtained for the device with SM1, which was the first example reported for efficient roll-coating fabrication of flexible large area small molecule solar cells with PCE exceeding...... methods. Four diketopyrrolopyrrole based small molecules (SMs 1-4) were utilized as electron donors with (6,6)phenyl- C61-butyric acid methyl ester as an acceptor and their photovoltaic performances based on roll-coated devices were investigated. The best power conversion efficiency (PCE) of 1...

PIE on Safety-Tested Loose Particles from Irradiated Compact 4-4-2

Energy Technology Data Exchange (ETDEWEB)

Hunn, John D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gerczak, Tyler J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Morris, Robert Noel [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Baldwin, Charles A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Montgomery, Fred C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2016-04-01

Post-irradiation examination (PIE) is being performed in support of tristructural isotropic (TRISO) coated particle fuel development and qualification for High Temperature Gas-cooled Reactors (HTGRs). This work is sponsored by the Department of Energy Office of Nuclear Energy (DOE-NE) through the Advanced Reactor Technologies (ART) Office under the Advanced Gas Reactor Fuel Development and Qualification (AGR) Program. The AGR-1 experiment was the first in a series of TRISO fuel irradiation tests initiated in 2006. The AGR-1 TRISO particles and fuel compacts were fabricated at Oak Ridge National Laboratory (ORNL) in 2006 using laboratory-scale equipment and irradiated for 3 years in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) to demonstrate and evaluate fuel performance under HTGR irradiation conditions. Post-irradiation examination was performed at INL and ORNL to study how the fuel behaved during irradiation, and to test fuel performance during exposure to elevated temperatures at or above temperatures that could occur during a depressurized conduction cooldown event. This report summarizes safety testing and post-safety testing PIE conducted at ORNL on loose particles extracted from irradiated AGR-1 Compact 4-4-2.

A histopathological score on baseline biopsies from elderly donors predicts outcome 1 year after renal transplantation

DEFF Research Database (Denmark)

Toft, Birgitte G; Federspiel, Birgitte H; Sørensen, Søren S

2012-01-01

wall thickness of arteries and/or arterioles. Nineteen renal baseline biopsies from 15 donors (age: 64 ± 10 years) were included and following consensus the histopathological score was 4.3 ± 2.1 (intraclass correlation coefficient: 0.81; confidence interval: 0.66-0.92). The donor organs were used......Kidneys from elderly deceased patients and otherwise marginal donors may be considered for transplantation and a pretransplantation histopathological score for prediction of postoperative outcome is warranted. In a retrospective design, 29 baseline renal needle biopsies from elderly deceased donors...... Danish donors a histopathological score on baseline renal needle biopsies, with at least ten glomeruli and one artery present, predicts graft function 1 year after transplantation....

Ultrasonic Coating and Holographic Exposure Technology. Phase 1

Science.gov (United States)

2015-09-01

Docmnents: Follow the procedures in DoD 5200.22-M, Industrial Security Manual, Section ll-19 or DoD 5200.1-R, Information Security Program Regulation...water vapor shine some light on the required quality of the intended product – eyewear lenses. The top surface of the lens having the waveplate must be...barrier coating industry and has a significant impact on the design of plastic organic light emitting diode displays and flexible photovoltaic devices

Modernização da Agricultura em Moçambique: determinantes da renda agrícola

Directory of Open Access Journals (Sweden)

Carlos E. Guanziroli

2015-03-01

Full Text Available O objetivo deste trabalho é verificar até que ponto as tecnologias oriundas da revolução verde foram efetivamente adotadas na África Subsaariana e, nos casos em que foram adotadas, se tiveram sucesso em melhorar a renda e a produtividade da agricultura. Para este fim, o trabalho faz primeiramente um breve resumo do estado das artes da revolução verde na África, mostrando quais países avançaram mais e como se correlaciona a utilização de fertilizantes químicos com os aumentos de produtividade. Faz-se também uma discussão sobre as características do processo de intensificação num caso em particular, o de Moçambique. Finalmente, com base nos microdados do Tratado de Inquérito Agrícola (TIA, se testa um modelo econométrico de MQO que visa avaliar os determinantes da renda agrícola e, em particular, do uso de fertilizantes químicos.

Plantas forrageiras cultivadas em assentamentos da reforma agrária visando mapear para o melhoramento participativo

Directory of Open Access Journals (Sweden)

Maria Tereza Bolzon Soster

2014-05-01

Full Text Available O presente trabalho visou atender a demanda de levantamento sobre as plantas forrageiras cultivadas em assentamentos da Reforma Agrária no Rio Grande do Sul para que um projeto de Melhoramento Participativo possa ser implantado para esse fim. Os dados foram levantados através dos alunos do Instituto Educar e seus assentamentos, totalizando 8 assentamentos, abrangendo 1019 famílias. Em média têm-se 16 espécies forrageiras por assentamento, entre espécies de inverno e de verão, com maior destaque à espécies de verão e maior contribuição de gramíneas (Poaceae. Notou-se que quanto maior o assentamento, mais espécies estão à disposição dos mesmos, enfatizando a importância da fragmentação agrária para a biodiversidade, inclusive de cultivos de plantas forrageiras. Os agricultores se demonstraram receptivos a programas de melhoramento de suas pastagens sobretudo quanto a adaptação e rendimento de massa seca. 

Mechanical Properties of Air Plasma Sprayed Environmental Barrier Coating (EBC) Materials

Science.gov (United States)

Richards, Bradley; Zhu, Dongming; Ghosn, Louis; Wadley, Haydn

2015-01-01

Development work in Environmental Barrier Coatings (EBCs) for Ceramic Matrix Composites (CMCs) has focused considerably on the identification of materials systems and coating architectures to meet application needs. The evolution of these systems has occurred so quickly that modeling efforts and requisite data for modeling lag considerably behind development. Materials property data exists for many systems in the bulk form, but the effects of deposition on the critical properties of strength and fracture behavior are not well studied. We have plasma sprayed bulk samples of baseline EBC materials (silicon, ytterbium disilicate) and tested the mechanical properties of these materials to elicit differences in strength and toughness. We have also endeavored to assess the mixed-mode fracture resistance, Gc, of silicon in a baseline EBC applied to SiCSiC CMC via four point bend test. These results are compared to previously determined properties of the comparable bulk material.

Effect of Hf Additions to Pt Aluminide Bond Coats on EB-PVD TBC Life

Science.gov (United States)

Nesbitt, James; Nagaraj, Ben; Williams, Jeffrey

2000-01-01

Small Hf additions were incorporated into a Pt aluminide coating during chemical vapor deposition (CVD) on single crystal RENE N5 substrates. Standard yttria-stabilized zirconia top coats were subsequently deposited onto the coated substrates by electron beam-physical vapor deposition (EB-PVD). The coated substrates underwent accelerated thermal cycle testing in a furnace at a temperature in excess of 1121 C (2050 F) (45 minute hot exposure, 15 minute cool to approximately 121 C (250 F)) until the thermal barrier coating (TBC) failed by spallation. Incorporating Hf in the bond coat increased the TBC life by slightly more than three times that of a baseline coating without added Hf. Scanning electron microscopy of the spalled surfaces indicated that the presence of the Hf increased the adherence of the thermally grown alumina to the Pt aluminide bond coat. The presence of oxide pegs growing into the coating from the thermally grown alumina may also partially account for the improved TBC life by creating a near-surface layer with a graded coefficient of thermal expansion.

Etiam specie inanium validus (Anais, XIII, 8, 3): o papel de Agrícola e Corbulão na narrativa de Tácito.

OpenAIRE

Aguiar, Mariana Alves de

2013-01-01

Programa de Pós-Graduação em História. Departamento de História, Instituto de Ciências Humanas e Sociais, Universidade Federal de Ouro Preto. A presente dissertação trata da análise do papel de dois generais presentes na narrativa de Tácito, Agrícola e Corbulão. O primeiro general encontra-se em uma biografia, Vida de Agrícola, e o segundo em uma narrativa histórica, os Anais de Tácito. Tácito nos apresenta esses generais como uma forma de exemplo de conduta aristocrática imperial. Pensamo...

Del hogar agrícola a los maestros queseros. La escuela granja de Tandil (Argentina, 1915-1960

Directory of Open Access Journals (Sweden)

Talía Violeta Gutiérrez

2015-01-01

Full Text Available La formación de recursos humanos y la generación de conocimientos adaptados a las condiciones de explotación de las diversas produccio-nes regionales en la Argentina ocuparon la atención de los técnicos del Ministerio de Agricultura de la Nación, de las entidades agraristas y de sectores políticos y educativos diversos desde inicios del siglo XX. No escapó a ese interés la preocupación por la mujer y el “hogar agrícola”. En el presente artículo fueron analizadas, en ese contexto, las primeras décadas de la Escuela Granja “Ramón Santamarina” de Tandil, un esta-blecimiento con una rica historia institucional que albergó la primera es-cuela del hogar agrícola del país, transformada pronto en granja-escuela y especializada en industria láctea. El tránsito del “hogar agrícola” a la preparación de maestros queseros -en el marco de la orientación productivista de las escuelas en la pro-puesta educativa del Ministerio-, los sujetos sociales involucrados, la es-pecialización en quesería y sus resultados, son algunas de las cuestiones analizadas. Esto se inserta en el contexto de un proyecto educativo agra-rio pensado no solo como fuente de mano de obra, vinculado a determi-nadas industrias agrarias, sino también –y tal vez más que nada– como irradiador de ese tipo de enseñanzas hacia la comunidad.

Histórico e os limites da reforma agrária na contemporaneidade brasileira History and limits of the agrarian reform in the Brazilian contemporary time

Directory of Open Access Journals (Sweden)

Paulo Nakatani

2012-06-01

Full Text Available Objetiva-se reconstituir a trajetória da questão fundiária (e agrária na experiência de maior concentração de riqueza e recursos vivenciada no âmbito do sistema capitalista, partindo-se da premissa de que a crescente desigualdade do modelo brasileiro passa necessariamente pela questão agrária. Num segundo momento, procede-se à análise dos limites atualmente colocados a qualquer possibilidade de uma Reforma Agrária ampla e estrutural, dados pelo avanço do agronegócio nos últimos dez anos, pela desmobilização política de parcela significativa da sociedade no que se refere a esta questão e pelos próprios limites estruturais da economia brasileira nos quadros da globalização financeira. O texto será dividido em seis sessões: a colonização e origens do latifúndio; b O modelo agroexportador e a ruptura incompleta; c a questão agrária e a industrialização brasileira; d a questão agrária e o agronegócio; e os limites da reforma agrária na contemporaneidade; f considerações finais.This paper aims at reconstructing the history of the land (agrarian issue considering the greatest concentration of wealth and resources in the capitalist system. The standpoint is that the growing inequality of the Brazilian model is related to the agrarian issue. Secondly, we analyze the limits ­currently placed on any possibility of a comprehensive and structural agrarian reform, due to the advancement of the agribusiness over the last ten years, the political demobilization of a significant portion of society that put this issue aside, and the limits of the Brazilian economy in the context of the financial globalization. The paper is divided into six parts: a colonization and origins of the large landed estates; b the agro-export model and the incomplete rupture; c the agrarian issue and the Brazilian industrialization; d the agrarian issue and the agribusiness; e the limits of the agrarian reform in the contemporary time; f final

Modelo de Precificação de Capital: Segmento de Commodities Agrícola

Directory of Open Access Journals (Sweden)

TÁCITO AUGUSTO FARIAS

2014-12-01

Full Text Available O objetivo do artigo é a aplicação do modelo de precificação de ativos conhecido na literatura de economia financeira como CAPITAL ASSET PRICING MODEL – MODELO DE PRECIFICAÇÃO DE ATIVOS DE CAPITAL, utilizando como ferramentas os balanços patrimoniais das empresas selecionadas. Brasil Ecodiesel indústria e comercio de biocombustíveis e óleos vegetais s.a. (v-agro e SLC Agrícola s.a. no período relativo ao ano de 2009 e 2010. Resultado fundamental: ambas as empresas no período em estudo apresentaram um beta inferior a 1, ou seja, risco menor que o risco do mercado. Descrevemos alguns resultados estatísticos que mostram o comportamento de ambas as empresas do setor de frigorifico. 

Proyección para la instalación de una empresa de servicios agrícolas y administrativos en Manabí

Directory of Open Access Journals (Sweden)

Carlos Oswaldo Balarezo Beltrón

2016-06-01

Full Text Available La investigación se realizó en los cantones Bolívar, Chone y Tosagua. El objetivo fue establecer la proyección de implantación de una empresa de servicios agrícolas y administrativos. La metodología se dividió en cuatro etapas: diagnóstico, análisis estratégico, programa de asistencia y socialización. Entre los principales cultivos de la zona se encontraron al cacao, tomate y plátano. Se determinó que problemas de sanidad vegetal, como hongos e insectos fueron los más importantes. La mayoría de los encuestados consideraron que necesitan un programa de asistencia administrativa que les ayude a planificar sus actividades. Los especialistas señalaron que la asistencia agrícola que se necesita es sobre control de plagas y pequeños sistema de riego. Los temas expuestos en la socialización fueron manejo integrado de plagas, aplicación de sistema de riego por goteo, manejo de fertilización y planificación estratégica en la finca. Palabras clave: Economía agrícola, ambiental, innovación tecnológica, ecológico, control.

Comparison of additive amount used in spin-coated and roll-coated organic solar cells

DEFF Research Database (Denmark)

Cheng, Pei; Lin, Yuze; Zawacka, Natalia Klaudia

2014-01-01

All-polymer and polymer/fullerene inverted solar cells were fabricated by spin-coating and roll-coating processes. The spin-coated small-area (0.04 cm(2)) devices were fabricated on indium tin oxide (ITO) coated glass substrates in nitrogen. The roll-coated large-area (1.0 cm(2)) devices were...

Thermally driven refrigeration by methanol adsorption on coatings of HKUST-1 and MIL-101(Cr)

International Nuclear Information System (INIS)

Kummer, Harry; Baumgartner, Max; Hügenell, Philipp; Fröhlich, Dominik; Henninger, Stefan K.; Gläser, Roger

2017-01-01

Highlights: • A novel approach of shaping MOFs as coatings on Al-substrates used as HX materials. • The efficiency of HKUST-1 and MIL-101(Cr) for refrigeration via Methanol sorption. • The thermal stability of the MOF coatings under application relevant conditions. • Focus on early implementation by use of commercially and pre-industrially MOFs. • Modelling of sorption uptakes under application conditions for apparatus design. - Abstract: A new and versatile binder-based metal organic framework-(MOF-) coating enables efficient use in fast-cycle adsorption chillers for cooling and refrigeration applications. Two different adsorbents were presented, HKUST-1 and Mil-101(Cr), with promising methanol adsorption characteristics and high loading capacities up to 1.22 g g"−"1. Polysiloxane-based coatings containing 65 and 80 wt% of the MOF adsorbents were produced and the adsorption characteristics were studied before and after extensive thermal treatment over 1000 cycles between 20 °C and 130 °C under methanol atmosphere by thermogravimetric analysis and X-ray diffractometry. Using the Dubinin-Astakhov approach, possible methanol loading lifts in a refrigeration process under different application conditions were quantified.

Coat condition of ringtailed lemurs, Lemur catta at Berenty Reserve, Madagascar: I. Differences by age, sex, density and tourism, 1996-2006.

Science.gov (United States)

Jolly, Alison

2009-03-01

An index of coat condition can be a non-invasive tool for tracking health and stress at population level. Coat condition in ringtailed lemurs, Lemur catta, was recorded during September-November birth seasons of 1996, 1997, 1999, and 2001-2006 at Berenty Reserve, Madagascar. Condition was scored on a scale from 0: full, fluffy coat with guard hairs present, to 5: half or more of body hairless. Adult males did not differ overall from adult females. Coats were worse in adults than in 2-year-old subadults; 1-year-old juveniles were intermediate. Mothers and adult males lost coat condition as the season progressed: non-mother females maintained condition. Years 1999-2002 scored better coats than either 1996-1997 or 2003-2006. Lemurs in high population density areas had worse coats than in natural forest, but tourist presence had less effect than density. Monitoring coat condition in an apparently healthy population reveals differences between population segments, and in a forest fragment with limited immigration or emigration it can track progressive changes, correcting impressions of progressive improvement or degradation over time. Above all it gives a baseline for response to climate changes or eventual pathology. (c) 2008 Wiley-Liss, Inc.

The MC1R and ASIP Coat Color Loci May Impact Behavior in the Horse

Science.gov (United States)

Jacobs, Lauren N.; Staiger, Elizabeth A.; Albright, Julia D.

2016-01-01

Shared signaling pathways utilized by melanocytes and neurons result in pleiotropic traits of coat color and behavior in many mammalian species. For example, in humans polymorphisms at MC1R cause red hair, increased heat sensitivity, and lower pain tolerance. In deer mice, rats, and foxes, ASIP polymorphisms causing black coat color lead to more docile demeanors and reduced activity. Horse (Equus caballus) base coat color is primarily determined by polymorphisms at the Melanocortin-1 Receptor (MC1R) and Agouti Signaling Protein (ASIP) loci, creating a black, bay, or chestnut coat. Our goal was to investigate correlations between genetic loci for coat color and temperament traits in the horse. We genotyped a total of 215 North American Tennessee Walking Horses for the 2 most common alleles at the MC1R (E/e) and ASIP (A/a) loci using previously published PCR and RFLP methods. The horses had a mean age of 10.5 years and comprised 83 geldings, 25 stallions, and 107 mares. To assess behavior, we adapted a previously published survey for handlers to score horses from 1 to 9 on 20 questions related to specific aspects of temperament. We utilized principle component analysis to combine the individual survey scores into 4 factors of variation in temperament phenotype. A factor component detailing self-reliance correlated with genotypes at the ASIP locus; black mares (aa) were more independent than bay mares (A_) (P = 0.0063). These findings illuminate a promising and novel animal model for future study of neuroendocrine mechanisms in complex behavioral phenotypes. PMID:26884605

Safety Evaluation of the ESP Sludge Washing Baselines Runs. Revision 1

International Nuclear Information System (INIS)

Gupta, M.K.

1994-08-01

The purpose is to provide the technical basis for the evaluation of Unreviewed Safety Question for the Extended Sludge Processing (ESP) Sludge Washing Baseline Runs. The Baseline runs are necessary: to ascertain the mechanical fitness of the equipment and modifications not operated since 1988 and to resolve technical questions associated with process control; i.e., sludge suspension, sludge settling, heat transfer, and temperature control. These issues need to be resolved prior to resumption of normal ESP operations. The equipment used for the Baseline runs are Tanks 42H and 51H and their associated equipment

Program reference schedule baseline

International Nuclear Information System (INIS)

1986-07-01

This Program Reference Schedule Baseline (PRSB) provides the baseline Program-level milestones and associated schedules for the Civilian Radioactive Waste Management Program. It integrates all Program-level schedule-related activities. This schedule baseline will be used by the Director, Office of Civilian Radioactive Waste Management (OCRWM), and his staff to monitor compliance with Program objectives. Chapter 1 includes brief discussions concerning the relationship of the PRSB to the Program Reference Cost Baseline (PRCB), the Mission Plan, the Project Decision Schedule, the Total System Life Cycle Cost report, the Program Management Information System report, the Program Milestone Review, annual budget preparation, and system element plans. Chapter 2 includes the identification of all Level 0, or Program-level, milestones, while Chapter 3 presents and discusses the critical path schedules that correspond to those Level 0 milestones

Updated global 3+1 analysis of short-baseline neutrino oscillations

Science.gov (United States)

Gariazzo, S.; Giunti, C.; Laveder, M.; Li, Y. F.

2017-06-01

We present the results of an updated fit of short-baseline neutrino oscillation data in the framework of 3+1 active-sterile neutrino mixing. We first consider ν e and {\\overline{ν}}_e disappearance in the light of the Gallium and reactor anomalies. We discuss the implications of the recent measurement of the reactor {\\overline{ν}}_e spectrum in the NEOS experiment, which shifts the allowed regions of the parameter space towards smaller values of | U e4|2. The β-decay constraints of the Mainz and Troitsk experiments allow us to limit the oscillation length between about 2 cm and 7 m at 3 σ for neutrinos with an energy of 1 MeV. The corresponding oscillations can be discovered in a model-independent way in ongoing reactor and source experiments by measuring ν e and {\\overline{ν}}_e disappearance as a function of distance. We then consider the global fit of the data on short-baseline {}_{ν_{μ}}^{(-)}{\\to}_{ν_e}^{(-)} transitions in the light of the LSND anomaly, taking into account the constraints from {}_{ν_e}^{(-)} and {}_{ν_{μ}}^{(-)} disappearance experiments, including the recent data of the MINOS and IceCube experiments. The combination of the NEOS constraints on | U e4|2 and the MINOS and IceCube constraints on | U μ4|2 lead to an unacceptable appearance-disappearance tension which becomes tolerable only in a pragmatic fit which neglects the MiniBooNE low-energy anomaly. The minimization of the global χ 2 in the space of the four mixing parameters Δ m 41 2 , | U e4|2, | U μ4|2, and | U τ4|2 leads to three allowed regions with narrow Δ m 41 2 widths at Δ m 41 2 ≈ 1.7 (best-fit), 1.3 (at 2 σ), 2.4 (at 3 σ) eV2. The effective amplitude of short-baseline {}_{ν_{μ}}^{(-)}{\\to}_{ν_e}^{(-)} oscillations is limited by 0.00048 ≲ sin2 2 ϑ eμ ≲ 0.0020 at 3 σ. The restrictions of the allowed regions of the mixing parameters with respect to our previous global fits are mainly due to the NEOS constraints. We present a comparison of the

Effect of once-weekly dulaglutide on glycated haemoglobin (HbA1c) and fasting blood glucose in patient subpopulations by gender, duration of diabetes and baseline HbA1c.

Science.gov (United States)

Gallwitz, Baptist; Dagogo-Jack, Samuel; Thieu, Vivian; Garcia-Perez, Luis-Emilio; Pavo, Imre; Yu, Maria; Robertson, Kenneth E; Zhang, Nan; Giorgino, Francesco

2018-02-01

To evaluate the efficacy and safety of dulaglutide 1.5 and 0.75 mg in patients with type 2 diabetes by subgroups of gender, duration of diabetes and baseline glycated haemoglobin (HbA1c) in the dulaglutide clinical development programme (AWARD-1 to -6 and -8 clinical trials). Change in HbA1c was analysed by gender, duration of diabetes (baseline HbA1c (baseline in weight, hypoglycaemia and gastrointestinal adverse events were evaluated for individual trials. In the pooled analysis of patients treated with dulaglutide 1.5 mg at 6 months, the reductions in HbA1c from baseline were similar across gender (men: least squares [LS] mean -1.26% [95% confidence interval {CI} -1.36, -1.16]; women: LS mean -1.33% [95% CI -1.43, -1.24]) and among duration of diabetes subgroups (baseline HbA1c ≥8.5% had greater HbA1c reductions than patients with baseline HbA1c baseline HbA1c subgroups, respectively; women had a numerically greater weight loss or less weight gain than men with both dulaglutide doses. There was no clinically meaningful difference in hypoglycaemia trends by gender or duration of diabetes. Hypoglycaemia incidence and rate were generally lower in patients with baseline HbA1c ≥8.5% than in those with baseline HbA1c, with greater HbA1c and FBG reductions in patients with a higher baseline HbA1c. Dulaglutide was well tolerated, with a safety profile similar to other glucagon-like peptide-1 receptor agonists. © 2017 John Wiley & Sons Ltd.

Characteristics and corrosion studies of vanadate conversion coating formed on Mg-14 wt%Li-1 wt%Al-0.1 wt%Ce alloy

Energy Technology Data Exchange (ETDEWEB)

Ma Yibin [School of Chemical Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China); Li Ning, E-mail: lininghit@263.net [School of Chemical Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China); Li Deyu [School of Chemical Engineering and Technology, Harbin Institute of Technology, Harbin 150001 (China); Zhang Milin; Huang Xiaomei [Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, Harbin Engineering University, Harbin 150001 (China)

2012-11-15

Highlights: Black-Right-Pointing-Pointer Vanadate film forms on the surface of Mg-Li-Al-Ce alloy. Black-Right-Pointing-Pointer Vanadate coating improves the corrosion resistance. Black-Right-Pointing-Pointer Vanadate coating is composed of Mg(OH){sub 2}, Li{sub 2}O and V{sub 2}O{sub 5}. - Abstract: Mg-14Li-1Al-0.1Ce alloy is immersed in NH{sub 4}VO{sub 3} + K{sub 3}(Fe(CN){sub 6}) solutions with different NH{sub 4}VO{sub 3} and/or K{sub 3}(Fe(CN){sub 6}) concentrations, and different immersion time. The surface morphology and composition of the vanadate coating are then characterized by scanning electron microscopy with energy dispersion spectroscopy (SEM-EDS) and X-ray photoelectron spectroscopy (XPS), and the corrosion behavior of the conversion coating is studied by polarization technique and electrochemical impedance spectroscopy (EIS). The experimental results indicate that the vanadate film with better corrosion resistance forms on Mg-Li-Al-Ce surface after the sample is immersed in 30 g L{sup -1} NH{sub 4}VO{sub 3} + 3.75 g L{sup -1} K{sub 3}(Fe(CN){sub 6}) solution at 80 Degree-Sign C for 10 min. The coating consists of V{sub 2}O{sub 5}, Li{sub 2}O and Mg(OH){sub 2}.

Detection and analysis of particles with failed SiC in AGR-1 fuel compacts

Energy Technology Data Exchange (ETDEWEB)

Hunn, John D., E-mail: hunnjd@ornl.gov [Oak Ridge National Laboratory (ORNL), P.O. Box 2008, Oak Ridge, TN 37831-6093 (United States); Baldwin, Charles A.; Gerczak, Tyler J.; Montgomery, Fred C.; Morris, Robert N.; Silva, Chinthaka M. [Oak Ridge National Laboratory (ORNL), P.O. Box 2008, Oak Ridge, TN 37831-6093 (United States); Demkowicz, Paul A.; Harp, Jason M.; Ploger, Scott A. [Idaho National Laboratory (INL), P.O. Box 1625, Idaho Falls, ID 83415-6188 (United States)

2016-09-15

Highlights: • Cesium release was used to detect SiC failure in HTGR fuel. • Tristructural-isotropic particles with SiC failure were isolated by gamma screening. • SiC failure was studied by X-ray tomography and SEM. • SiC degradation was observed after irradiation and subsequent safety testing. - Abstract: As the primary barrier to release of radioactive isotopes emitted from the fuel kernel, retention performance of the SiC layer in tristructural isotropic (TRISO) coated particles is critical to the overall safety of reactors that utilize this fuel design. Most isotopes are well-retained by intact SiC coatings, so pathways through this layer due to cracking, structural defects, or chemical attack can significantly contribute to radioisotope release. In the US TRISO fuel development effort, release of {sup 134}Cs and {sup 137}Cs are used to detect SiC failure during fuel compact irradiation and safety testing because the amount of cesium released by a compact containing one particle with failed SiC is typically ten or more times higher than that released by compacts without failed SiC. Compacts with particles that released cesium during irradiation testing or post-irradiation safety testing at 1600–1800 °C were identified, and individual particles with abnormally low cesium retention were sorted out with the Oak Ridge National Laboratory (ORNL) Irradiated Microsphere Gamma Analyzer (IMGA). X-ray tomography was used for three-dimensional imaging of the internal coating structure to locate low-density pathways through the SiC layer and guide subsequent materialography by optical and scanning electron microscopy. All three cesium-releasing particles recovered from as-irradiated compacts showed a region where the inner pyrocarbon (IPyC) had cracked due to radiation-induced dimensional changes in the shrinking buffer and the exposed SiC had experienced concentrated attack by palladium; SiC failures observed in particles subjected to safety testing were

Incentivos a la innovación de la biotecnología agrícola-alimentaria en México

Directory of Open Access Journals (Sweden)

Marcela Amaro-Rosales

2015-01-01

Full Text Available En el artículo analizamos la innovación biotecnológica relacionada con los sectores agrícola y alimentario en México. Tomamos en cuenta las políticas públicas, las leyes y las reglamentaciones; la dinámica del sector y del merado. Asimismo, analizamos la forma en la que las empresas agro-alimentarias pueden aprovechar los insumos de conocimiento científico y tecnológico que ofrece la biotecnología. La principal conclusión es que actualmente el marco institucional regulatorio y la dinámica del mercado establecen más barreras que incentivos para el desarrollo y aplicación de innovaciones biotecnológicas y con ello lograr una mejora en la cali - dad de los alimentos y un incremento en la competitividad de las empresas y del sector agrícola en el país.

Morbilidad laboral en el sector agrícola en trabajadores afiliados a una administradora de riesgos laborales (ARL) de Colombia, durante el periodo 2011-2012.

OpenAIRE

Velásquez Bueno, Diana Marcela

2013-01-01

Este estudio muestra la prevalencia por enfermedad laboral de un grupo de trabajadores afiliados a una ARL en Colombia. Compara la morbilidad laboral entre dos grupo de trabajadores expuestos y no expuestos al trabajo agrícola y al interior del grupo de trabajadores agrícolas agrupados en las actividades de corte de caña, cultivo de banano y flores. Se realizó un estudio descriptivo de tipo transversal durante el periodo 2011-2012, mediante la revisión de una base de datos de morbilidad la...

Aspectos constitucionais do direito agrário emenda constitucional N° 10/64

Directory of Open Access Journals (Sweden)

José Carlos Vieira

1988-07-01

Full Text Available This paper, presents a brief history of the constitutional work applied to property rights in Brazil, mainly to those regarding land property. lt also shows the development of agrarian rights as an independent branch of the juridical prescription up to its effective recognition. It slightly shows the important role of the social function of property in constitutional texts as to support governmental actions aiming at an agrarian reform, and any other tendency to alter the rural profile of the country. This work is aimed to show that, despite a set of laws related to the agrarian reality of this country, the facts and data make it clear that nothing has been done about it up to today. The research Our constitutional texts shows that some advances towards the effectiveness of the social function of property principles have been made; nevertheless, the constitution to be promulgated by the year 1988, surprisingly takes a step backwards as to this chapter for it decreases the scope that it had in former constitutions and even in the original ones by authoritarian governments.O presente trabalho contém um resumo histórico do tratamento constitucional reservado ao direito de propriedade no Brasil, especialmente à propriedade da terra, bem assim a evolução do direito agrário como ramo autônomo do ordenamento jurídico, até o seu efetivo reconhecimento como tal. Registra, mesmo que rapidamente, a importância que teve a adotação do princípio da "função social da propriedade" nos textos constitucionais, de forma a respaldar ações governamentais objetivando a realização da reforma agrária e outras medidas tendentes a alterar o perfil rural do país. O trabalho procura mostrar, também, que, malgrado dispor o pais de um rol de leis capazes de dar suporte a propostas destinadas a promover uma efetiva mudança na realidade agrária, os fatos demonstram claramente que isto não ocorreu até hoje. A pesquisa nos textos constitucionais mostra

The development and characterization of advanced broadband mirror coatings for the far-UV

Science.gov (United States)

Egan, Arika; Fleming, Brian T.; Wiley, James; Quijada, Manuel; Del Hoyo, Javier; Hennessy, John; Hicks, Brian; France, Kevin; Kruczek, Nicholas; Erickson, Nicholas

2017-08-01

We present a progress report on the development of new broadband mirror coatings that demonstrate > 80% reflectivities from 1020-5000Å. Four different coating recipes are presented as candidates for future far-ultraviolet (FUV) sensitive broadband observatories. Three samples were first coated with aluminum (Al) and lithium fluoride (LiF) at the NASA Goddard Space Flight Center (GSFC) using a new high-temperature physical vapor deposition (PVD) process. Two of these samples then had an ultrathin (10-20 Å) protective coat of either magnesium fluoride (MgF2) or aluminum fluoride (AlF3) applied using atomic later deposition (ALD) at the NASA Jet Propulsion Laboratory (JPL). A fourth sample was coated with Al and a similar high temperature PVD coating of AlF3. Polarized reflectivities into the FUV for each sample were obtained through collaboration with the Synchrotron Ultraviolet Radiation Facility at the National Institute of Standards and Technology. We present a procedure for using these reflectivities as a baseline for calculating the optical constants of each coating recipe. Given these results, we describe plans for improving our measurement methodology and techniques to develop and characterize these coating recipes for future FUV missions.

The Influence of 1α.25-Dihydroxyvitamin D3 Coating on Implant Osseointegration in the Rabbit Tibia

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Yoshihito

2014-10-01

Full Text Available Objectives: This study aims to evaluate bone response to an implant surface modified by 1α,25-dihydroxyvitamin D3 [1.25-(OH2D3] in vivo and the potential link between 1.25-(OH 2D3 surface concentration and bone response. Material and Methods: Twenty-eight implants were divided into 4 groups (1 uncoated control, 3 groups coated with 1.25-(OH2D3 in concentrations of 10-8, 10-7 and 10-6 M respectively, placed in the rabbit tibia for 6 weeks. Topographical analyses were carried out on coated and uncoated discs using interferometer and atomic-force-microscope (AFM. Twenty-eight implants were histologically observed (bone-to-implant-contact [BIC] and new-bone-area [NBA]. Results: The results showed that the 1.25-(OH2D3 coated implants presented a tendency to osseointegrate better than the non-coated surfaces, the differences were not significant (P > 0.05. Conclusions: The effect of 1.25-(OH2D3 coating to implants suggested possible dose dependent effects, however no statistical differences could be found. It is thought that the base substrate topography (turned could not sustain sufficient amount of 1.25-(OH2D3 enough to present significant biologic responses. Thus, development a base substrate that can sustain 1.25-(OH2D3 for a long period is necessary in future studies.

Glass-Coated Beryllium Mirrors for the LHCb RICH1 Detector

CERN Document Server

Barber, G J; Cameron, W; D'Ambrosio, C; Frei, C; Harnew, N; Head, R; Khimitch, Y P; Khmelnikov, V A; Loveridge, P W; Metlica, F; Obraztsov, V F; Piedigrossi, D; Sizenev, V; Kompozit Joint Stock Company, Moscow, Russia; Szczypka, P M; Ullaland, O; Vygosky, E; Websdale, D M

2007-01-01

The design, manufacture and testing of lightweight glass-coated beryllium spherical converging mirrors for the RICH1 detector of LHCb are described. The mirrors need to be lightweight to minimize the material budget and fluorocarbon-compatible to avoid degradation in the RICH1 C4F10 gas radiator. Results of the optical measurements for the small-sized prototypes and for the first full-sized prototype mirror are reported.

Marketing in the pre-development process of agricultural machines: a reference model Marketing no pré-desenvolvimento de máquinas agrícolas: um modelo de referência

Directory of Open Access Journals (Sweden)

Alexandre S. de Oliveira

2012-08-01

Full Text Available The theme of the research is the development of the domain of marketing knowledge in the design of agricultural machinery. It is developed throughout the design of agricultural machinery in order to identify the corporate and customers needs and to develop strategies to satisfy these needs. The central problem of the research questions which marketing tools to apply on pre-development process of farm machinery, in order to increase the market value of the products and of the company and, consequently, generate competitive advantage to the manufacturers of agricultural machinery. As methodology, it was developed bibliographical research and multicase study of the development process of agricultural machinery developed by small, medium and large companies and the academy. As a result, a marketing reference model was elaborated for the pre-development stage of agricultural machinery, which outlines the activities, tasks, mechanisms and controls that can be used in strategic planning and in products planning of agricultural machinery manufacturers, contributing to explain the explicit knowledge in the marketing field.O tema de pesquisa é o desenvolvimento do domínio de conhecimento de marketing no projeto de máquinas agrícolas. Este é desenvolvido ao longo do projeto de máquinas agrícolas a fim de identificar as necessidades dos clientes e da corporação e criar estratégias para que sejam satisfeitas. O problema central de pesquisa questiona quais mecanismos de marketing utilizar no processo de pré-desenvolvimento de máquinas agrícolas, para aumentar o valor de mercado dos produtos e da empresa e, conseqüentemente, gerar um diferencial competitivo às fabricantes de máquinas agrícolas. Como metodologia desenvolveu-se pesquisas bibliográficas e estudo de multicasos do processo de desenvolvimento de máquinas agrícolas desenvolvido pelas pequenas, médias e grandes empresas e pela academia. Como resultado elaborou-se um modelo

Weightless Environment Training Facility (WETF) materials coating evaluation, volume 1

Science.gov (United States)

1995-01-01

The Weightless Environment Training Facility Material Coating Evaluation project has included preparing, coating, testing, and evaluating 800 test panels of three differing substrates. Ten selected coating systems were evaluated in six separate exposure environments and subject to three tests for physical properties. Substrate materials were identified, the manner of surface preparation described, and exposure environments defined. Exposure environments included immersion exposure, cyclic exposure, and field exposure. Cyclic exposures, specifically QUV-Weatherometer and the KTA Envirotest were found to be the most agressive of the environments included in the study when all three evaluation criteria are considered. This was found to result primarily from chalking of the coatings under ultraviolet (UV) light exposure. Volumes 2 and 3 hold the 5 appendices to this report.

Obreros agrícolas migrantes en Sinaloa

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Florencio Posadas Segura

2015-01-01

Full Text Available el objetivo de este artículo es demostrar la presencia sig-nificativa de los obreros agrícolas migrantes, algunas carac-terísticas que la explican y la pauperización que experimen-tan. La causa principal de la migración es la desocupación;los empresarios controlan los métodos de contratación, tras-portación y explotación, y los jornaleros rurales migrantestrabajan más, ganan menos y su situación es mayormentemiserable. Esto se ilustra con el caso de Villa Benito Juárez,Sinaloa, que prueba la gran importancia de los asalariadosestacionales del campo, como auténticos productores de lariqueza, y la paradoja de su condición de pobreza aguda. Elpatrón migratorio interno y externo descubierto contradicelos estereotipos prevalecientes, en el marco de la reestruc-turación productiva y laboral de la agricultura mexicana yla incorporación de fuerza de trabajo asalariada pagada pordebajo de su valor, segmentada y dosificada conveniente-mente de acuerdo con la estrategia del capital, guiada por elespíritu de la ganancia máxima.

33 CFR 2.20 - Territorial sea baseline.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Territorial sea baseline. 2.20... JURISDICTION Jurisdictional Terms § 2.20 Territorial sea baseline. Territorial sea baseline means the line.... Normally, the territorial sea baseline is the mean low water line along the coast of the United States...

Estimación de la movilidad del ibuprofeno en suelos agrícolas

OpenAIRE

Biel Maeso, Miriam

2011-01-01

Los productos farmacéuticos y de higiene personal están emergiendo como contaminantes en el medio ambiente, lo que conlleva una creciente preocupación en la conciencia de la población. La mayoría de los estudios sobre el destino ambiental de estos productos se han centrado en los procesos de tratamiento de las aguas residuales, en los ambientes acuáticos, y en los lodos de depuración, sin embargo, poco se sabe acerca de su comportamiento en los suelos agrícolas. Máster Universitario en Hid...

The development of calculational methods and assessment standards for AGR refuelling safety cases

International Nuclear Information System (INIS)

Dawson, J.W.; Grant, R.J.; Thomas, D.L.

1995-01-01

This paper considers the methods used to assess the protection needed against hazards in the AGR fuel route. These methods are all directed towards the objective of showing that all postulated events taking place during refuelling are acceptable within agreed criteria of severity versus frequency. The methods allow the determination of temperatures arising in various hazards, from which estimates can be made of the radiological release, if any, which would occur. Comparison of this estimate with the level considered acceptable at the fault frequency leads to the requirement for protection. (author)

High-temperature air oxidation of E110 and Zr-1%Nb alloys claddings with coatings

International Nuclear Information System (INIS)

Kuprin, A.S.; Belous, V.A.; Voyevodin, V.N.; Bryk, V.V.; Vasilenko, R.L.; Ovcharenko, V.D.; Tolmachova, G.N.; V'yugov, P.N.

2014-01-01

Results of experimental study of the influence of protective vacuum-arc claddings on the base of compounds zirconium-chromium and of its nitrides on air oxidation resistance at temperatures 660, 770, 900, 1020, 1100 deg C during 3600 s. of tubes produced of zirconium alloys E110 and Zr-1%Nb (calcium-thermal alloy of Ukrainian production) are presented. Change of hardness, the width of oxide layer and depth of oxygen penetration into alloys from the side of coating and without coating are investigated by the methods of nanoindentation and by scanning electron microscopy. It is shown that the thickness of oxide layer in zirconium alloys at temperatures 1020 and 1100 deg C from the side of the coating doesn't exceed 5 μm, and from the unprotected side reaches the value of ≥ 120 μm with porous and rough structure. Tubes with coatings save their shape completely independently of the type of alloy; tubes without coatings deform with the production of through cracks

La sucesión "mortis causa" en la explotación agrícola familiar

Directory of Open Access Journals (Sweden)

José Luis De Los Mozos

2015-01-01

Full Text Available Llevo nada menos que cuarenta años dando vueltas al tema de la sucesión mortis causa en el Derecho agrario y más concretamente, al de la sucesión en la explotación agrícola. Esto no constituye ningún mérito, naturalmente, no es más que una mera circunstancia que acredita, cuando mucho, la firmeza de una convicción. Durante este tiempo, con mayor o menor contacto con la realidad social, he seguido y sigo fiel a mis puntos de vista originarios; no es que nada haya cambiado en todos estos años, sino que ha cambiado casi todo.Pero es que las soluciones que me parecían entonces muy dudosas, ahora me parecen inadmisibles.La evolución económica y social, ha puesto de relieve que las ideas que se utilizaban hace medio siglo en la materia, actualmente han quedado obsoletas (...Contenido: Una distinción obligada y un recuerdo inevitable. El recurso a la atribución preferente. Las condicionantes de la atribución preferente. El concepto de explotación agrícola. La reforma del derecho sucesorio como recapitulación

Integração vertical como estratégia de apropriação de valor: um estudo exploratório no canal de distribuição de produtos agrícolas Alternative marketing channels in order to attenuate the power of retail chains: agrícola Pedra Branca case study

Directory of Open Access Journals (Sweden)

Vivian Lara dos Santos Silva

2009-03-01

Full Text Available Neste artigo, investiga-se a adoção de canais alternativos para a comercialização de produtos agrícolas como forma de atenuar o poder, cada vez maior, exercido pelas grandes redes varejistas. O artigo investiga a decisão - e os efeitos daí decorrentes - de uma determinada empresa sediada no interior paulista, agrícola Pedra Branca, quanto à operacionalização verticalizada de uma butique de frutas, legumes e verduras (FLVs. Consciente dos novos padrões demandados pelo consumidor, a estratégia da empresa alvo do estudo foi combinar a oferta regular de produtos frescos, de qualidade intrínseca padronizada e preços atrativos, a um serviço diferenciado, baseado em um alto valor na experiência de compra. Esta estratégia fundamenta-se no anseio dos consumidores de, mais do que simplesmente adquirir produtos, experimentar sensações, as quais vividas em momentos de lazer exerceriam um grande poder de diferenciação. Realizou-se um estudo de caso baseado em entrevistas em profundidade semiestruturadas com diretores e gerentes da empresa. Como resultado, as evidências empíricas sugerem: 1 a verticalização (integração vertical da atividade de comercialização como uma alternativa para a apropriação de valor da produção ao longo do canal de distribuição; e 2 o desafio da gestão do suprimento como requisito-chave para a adequada gestão do valor de uma marca. Considera-se oportuno lembrar, porém, que, em decorrência das limitações próprias da metodologia de estudos de caso, estas tais evidências devem ser entendidas como proposição a ser testada em trabalhos quantitativos futuros, ou mesmo melhor embasada via condução de estudos multicaso.This paper aims to analyze the search for alternative marketing channels of industry and rural producers in order to attenuate the power of retail chains over the sale of products and services. In special, we focus on the rural producers' perspective investigating the decision of

Avaliação económica de tarifas de água no uso agrícola: um estudo de caso no Sul de Portugal

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Rui Fragoso

2009-09-01

Full Text Available Este artigo avalia os efeitos de políticas de tarifas da água no uso agrícola, em termos do consumo de água, do aproveitamento das áreas beneficiadas com regadio, do rendimento do produtor agrícola, da recuperação dos custos com a água e do desenvolvimento agrícola. A metodologia utilizada baseia-se na elaboração de um modelo de programação matemática multiperíodo, adaptado às características específicas de uma empresa agrícola do Sul de Portugal. Foram analisadas a tarifa fixa por área beneficiada, a tarifa volumétrica por metro cúbico de água consumida, a tarifa binómica e a tarifa progressiva. Para as simulações, foram considerados um cenário produtivo tradicional e um cenário produtivo alternativo, em que são introduzidas culturas de valor acrescentado.This paper evaluates the effects of water tariffs in irrigation, in terms of water consumption, land irrigated, farm income, water cost recovery and agricultural investment. The methodology is based on a multiperiod mathematical programming model, which was applied to the specific characteristics of a representative farm in southern Portugal. The main aspects analyzed were: the fix tariff per area benefited, the volumetric tariff per cubic meter of water consumed, the mix tariff and the increasing block tariff. For the simulations, it was considered a traditional productive scenario and an alternative scenario, which include value added crops.

Crack Driving Forces in a Multilayered Coating System for Ceramic Matrix Composite Substrates

Science.gov (United States)

Ghosn, Louis J.; Zhu, Dongming; Miller, Robert A.

2005-01-01

The effects of the top coating thickness, modulus and shrinkage strains on the crack driving forces for a baseline multilayer Yttria-Stabilized-Zirconia/Mullite/Si thermal and environment barrier coating (TEBC) system for SiC/SiC ceramic matrix composite substrates are determined for gas turbine applications. The crack driving forces increase with increasing modulus, and a low modulus thermal barrier coating material (below 10 GPa) will have no cracking issues under the thermal gradient condition analyzed. Since top coating sintering increases the crack driving forces with time, highly sintering resistant coatings are desirable to maintain a low tensile modulus and maintain a low crack driving force with time. Finite element results demonstrated that an advanced TEBC system, such as ZrO2/HfO2, which possesses improved sintering resistance and high temperature stability, exhibited excellent durability. A multi-vertical cracked structure with fine columnar spacing is an ideal strain tolerant coating capable of reducing the crack driving forces to an acceptable level even with a high modulus of 50 GPa.

Modelo para el monitoreo y seguimiento de indicadores de sostenibilidad del recurso hídrico en el sector agrícola

Directory of Open Access Journals (Sweden)

Carvajal Escobar Yesid

2011-12-01

Full Text Available El sistema de monitoreo y seguimiento permite identificar, a través de indicadores e índices, la sostenibilidad del recurso hídrico en el sector agrícola de la microcuenca Centella (Dagua-Valle del Cauca. Este modelo de monitoreo permite evaluar continua y sistemáticamente el progreso y los cambios ocasionados por la ejecución de un conjunto de actividades en un período de tiempo determinado. De igual manera, a través de este sistema es posible realizar un seguimiento y verificar en qué medida se cumplen las metas propuestas de sostenibilidad del recurso hídrico en el sector agrícola a nivel: biofísico, tecnológico, político-institucional y socioeconómico.

Modelo para el monitoreo y seguimiento de indicadores de sostenibilidad del recurso hídrico en el sector agrícola

Directory of Open Access Journals (Sweden)

Wilmar Loaiza Cerón

2011-01-01

Full Text Available El sistema de monitoreo y seguimiento permite identificar, a través de indicadores e índices, la sostenibilidad del recurso hídrico en el sector agrícola de la microcuenca Centella (Dagua-Valle del Cauca. Este modelo de monitoreo permite evaluar continua y sistemáticamente el progreso y los cambios ocasionados por la ejecución de un conjunto de actividades en un período de tiempo determinado. De igual manera, a través de este sistema es posible realizar un seguimiento y verificar en qué medida se cumplen las metas propuestas de sostenibilidad del recurso hídrico en el sector agrícola a nivel: biofísico, tecnológico, político-institucional y socioeconómico.

Cryosat Level1b SAR/Sarin: Improving the Quality of the Baseline C Products

Science.gov (United States)

Scagliola, M.; Fornari, M.; Tagliani, N.; Frommknecht, B.; Bouffard, J.; Parrinello, T.

2014-12-01

CryoSat was launched on the 8th April 2010 and it is the first European ice mission dedicated to monitoring precise changes in the thickness of polar ice sheets and floating sea ice over a 3-year period. Cryosat carries an innovative radar altimeter called the Synthetic Aperture Interferometric Altimeter (SIRAL), that transmits pulses at a high pulse repetition frequency thus making the received echoes phase coherent and suitable for azimuth processing. This allows to reach a significantly improved along track resolution with respect to traditional pulse-width limited altimeters. CryoSat is the first altimetry mission operating in SAR mode and continuous improvement in the Level1 Instrument Processing Facility (IPF1) are being identified, tested and validated in order to improve the quality of the Level1b products. Towards the release of the BaselineC of the CryoSat Level1b SAR/SARin products, that is expected at the end of 2014, several improvements have been identified: a datation bias of about -0.5195 ms will be corrected a range bias of about 0.6730 m will be corrected The range window size will be doubled with respect to BaselineB, so that the in Level1b products the waveforms will be doubled too Improved processing for 1Hz echoes to have sharper waveforms Surface sample stack weighting to filter out the single look echoes acquired at highest look angle, that results in a sharpening of the 20Hz waveforms Additional auxiliary information related to the mispointing angles of the instrument as well as to the stacks of single look echoes will be added This poster details the main quality improvements that are foreseen to be included in the CryoSat Level1b SAR/SARin products in BaselineC.

Trabalhismo, reforma agrária, legislação para as populações rurais: uma abordagem do projeto político de Fernando Ferrari

Directory of Open Access Journals (Sweden)

Ricardo Oliveira da Silva

2015-05-01

Full Text Available No presente texto, apresentamos uma abordagem introdutória do projeto político de Fernando Ferrari para a questão agrária. Ao longo da década de 1950 e começo dos anos de 1960, esse autor participou das discussões em torno dos problemas rurais brasileiros com base na doutrina trabalhista, desenvolvida por Alberto Pasqualini. Nesse sentido, destacamos o projeto trabalhista defendido por Fernando Ferrari para o campo mediante dois temas constantes em seus escritos: a reforma agrária e a legislação para a população rural.

Sintering Characteristics of Multilayered Thermal Barrier Coatings Under Thermal Gradient and Isothermal High Temperature Annealing Conditions

Science.gov (United States)

Rai, Amarendra K.; Schmitt, Michael P.; Bhattacharya, Rabi; Zhu, Dongming; Wolfe, Douglas E.

2014-01-01

Pyrochlore oxides have most of the relevant attributes for use as next generation thermal barrier coatings such as phase stability, low sintering kinetics and low thermal conductivity. One of the issues with the pyrochlore oxides is their lower toughness and therefore higher erosion rate compared to the current state-of-the-art TBC material, yttria (6 to 8 wt%) stabilized zirconia (YSZ). In this work, sintering characteristics were investigated for novel multilayered coating consisted of alternating layers of pyrochlore oxide viz Gd2Zr2O7 and t' low k (rare earth oxide doped YSZ). Thermal gradient and isothermal high temperature (1316 C) annealing conditions were used to investigate sintering and cracking in these coatings. The results are then compared with that of relevant monolayered coatings and a baseline YSZ coating.

Inspeção periódica de pulverizadores agrícolas

OpenAIRE

Gandolfo, Marco Antonio [UNESP

2001-01-01

Para a otimização no uso de agroquímicos, vários países tem realizado avaliações periódicas em pulverizadores agrícolas. No Brasil, o reconhecimento do estado destas máquinas, pode nortear pesquisas e investimentos em orientação de uso e manutenção. Os objetivos deste trabalho foram avaliar o estado de pulverizadores em uso na agricultura nacional, estudar a necessidade de implantação de inspeções periódicas em tais máquinas no Brasil e desenvolver metodologia específica para as condições bra...

O direito do comércio internacional no setor agrícola

OpenAIRE

D'Ávila, André Luiz Bettega

2006-01-01

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Ciências Jurídicas. Programa de Pós-Graduação em Direito. A dissertação analisa a regulamentação jurídica dos subsídios agrícolas à exportação na Organização Mundial do Comércio (OMC) e objetiva destacar pontos-chave para ação e pesquisa jurídica sobre o tema no contexto das negociações multilaterais em curso na Rodada Doha. A pesquisa encontra lastro nos Acordos e na jurisprudência da OMC, na doutrina estrangeira, ...

Cu2+1O coated polycrystalline Si nanoparticles as anode for lithium-ion battery.

Science.gov (United States)

Zhang, Junying; Zhang, Chunqian; Wu, Shouming; Liu, Zhi; Zheng, Jun; Zuo, Yuhua; Xue, Chunlai; Li, Chuanbo; Cheng, Buwen

2016-12-01

Cu2+1O coated Si nanoparticles were prepared by simple hydrolysis and were investigated as an anode material for lithium-ion battery. The coating of Cu2+1O on the surface of Si particles remarkably improves the cycle performance of the battery than that made by the pristine Si. The battery exhibits an initial reversible capacity of 3063 mAh/g and an initial coulombic efficiency (CE) of 82.9 %. With a current density of 300 mA/g, its reversible capacity can remains 1060 mAh/g after 350 cycles, corresponding to a CE ≥ 99.8 %. It is believed that the Cu2+1O coating enhances the electrical conductivity, and the elasticity of Cu2+1O further helps buffer the volume changes during lithiation/delithiation processes. Experiment results indicate that the electrode maintained a highly integrated structure after 100 cycles and it is in favour of the formation of stable solid electrolyte interface (SEI) on the Si surface to keep the extremely high CE during long charge and discharge cycles.

Ablation Behavior of Plasma-Sprayed La1-xSrxTiO3+δ Coating Irradiated by High-Intensity Continuous Laser.

Science.gov (United States)

Zhu, Jinpeng; Ma, Zhuang; Gao, Yinjun; Gao, Lihong; Pervak, Vladimir; Wang, Lijun; Wei, Chenghua; Wang, Fuchi

2017-10-11

Laser protection for optical components, particularly those in high-power laser systems, has been a major concern. La 1-x Sr x TiO 3+δ with its good optical and thermal properties can be potentially applied as a high-temperature optical protective coating or high-reflectivity material for optical components. However, the high-power laser ablation behavior of plasma-sprayed La 1-x Sr x TiO 3+δ (x = 0.1) coatings has rarely been investigated. Thus, in this study, laser irradiation experiments were performed to study the effect of high-intensity continuous laser on the ablation behavior of the La 1-x Sr x TiO 3+δ coating. The results show that the La 1-x Sr x TiO 3+δ coating undergoes three ablation stages during laser irradiation: coating oxidation, formation and growth of new structures (columnar and dendritic crystals), and mechanical failure. A finite-element simulation was also conducted to explore the mechanism of the ablation damage to the La 1-x Sr x TiO 3+δ coating and provided a good understanding of the ablation behavior. The apparent ablation characteristics are attributed to the different temperature gradients determined by the reflectivity and thermal diffusivity of the La 1-x Sr x TiO 3+δ coating material, which are critical factors for improving the antilaser ablation property. Now, the stainless steel substrate deposited by it can effectively work as a protective shield layer against ablation by laser irradiation.

Baseline status and dose to the penile bulb predict impotence 1 year after radiotherapy for prostate cancer

Energy Technology Data Exchange (ETDEWEB)

Cozzarini, Cesare; Badenchini, Fabio [San Raffaele Scientific Institute, Radiotherapy, Milano (Italy); Rancati, Tiziana [Fondazione IRCCS Istituto Nazionale dei Tumori, Prostate Cancer Program, Milan (Italy); Palorini, Federica; Improta, Ilaria; Fiorino, Claudio [San Raffaele Scientific Institute, Medical Physics, Milan (Italy); Avuzzi, Barbara [Fondazione IRCCS Istituto Nazionale dei Tumori, Radiation Oncology 1, Milan (Italy); Degli Esposti, Claudio [Ospedale Bellaria, Radiotherapy, Bologna (Italy); Girelli, Giuseppe [Ospedale ASL9, Radiotherapy, Ivrea (Italy); Vavassori, Vittorio [Cliniche Gavazzeni-Humanitas, Radiotherapy, Bergamo (Italy); Valdagni, Riccardo [Fondazione IRCCS Istituto Nazionale dei Tumori, Prostate Cancer Program, Milan (Italy); Fondazione IRCCS Istituto Nazionale dei Tumori, Radiation Oncology 1, Milan (Italy)

2016-05-15

To assess the predictors of the onset of impotence 1 year after radiotherapy for prostate cancer. In a multi-centric prospective study, the International Index of Erectile Function (IIEF) questionnaire-based potency of 91 hormone-naive and potent patients (IIEF1-5 > 11 before radiotherapy) was assessed. At the time of this analysis, information on potency 1 year after treatment was available for 62 of 91 patients (42 treated with hypofractionation: 2.35-2.65 Gy/fr, 70-74.2 Gy; 20 with conventional fractionation: 74-78 Gy). Prospectively collected individual information and D{sub max}/D{sub mean} to the penile bulb were available; the corresponding 2 Gy-equivalent values (EQD2 {sub max}/EQD2 {sub mean}) were also considered. Predictors of 1-year impotency were assessed through uni- and multi-variable backward logistic regression: The best cut-off values discriminating between potent and impotent patients were assessed by ROC analyses. The discriminative power of the models and goodness-of-fit were measured by AUC analysis and the Hosmer-Lemeshow (H and L) test. At 1-year follow-up, 26 of 62 patients (42 %) became impotent. The only predictive variables were baseline IIEF1-5 values (best cut-off baseline IIEF1-5 ≥ 19), D{sub max} ≥ 68.5 Gy and EQD2 {sub max} ≥ 74.2 Gy. The risk of 1-year impotence may be predicted by a two-variable model including baseline IIEF1-5 (OR: 0.80, p = 0.003) and EQD2 {sub max} ≥ 74.2 Gy (OR: 4.1, p = 0.022). The AUC of the model was 0.77 (95% CI: 0.64-0.87, p = 0.0007, H and L: p = 0.62). The 1-year risk of impotency after high-dose radiotherapy in potent men depends on the EQD2 {sub max} to the penile bulb and on baseline IIEF1-5 values. A significant reduction in the risk may be expected mainly when sparing the bulb in patients with no/mild baseline impotency (IIEF1-5 > 17). (orig.) [German] Beurteilung von Praediktoren fuer das Auftreten von Impotenz 1 Jahr nach Radiotherapie bei Prostatakrebs. In einer multizentrischen

Fluidized-Bed Coating with Sodium Sulfate and PVA-TiO2, 1. Review and Agglomeration Regime Maps

DEFF Research Database (Denmark)

Hede, Peter Dybdahl; Bach, Poul; Jensen, Anker Degn

2009-01-01

-TiO2. The coating experiments were conducted in a medium-scale top-spray MP-1 fluid bed, and many rheological experiments were performed on the coating formulations to support the interpretation of the fluid-bed coating results. In this first part of the study, a thorough introduction to the inorganic...... salt and polymer film coating is provided, along with a presentation of the equipment and materials being used in this and the following papers. Results from agglomeration studies over a broad range of process conditions are presented, showing that the tendency toward agglomeration is always less...

Límites de consistencia y sus implicaciones agrícolas en un suelo ultisol de sabana del estado Monagas, Venezuela

Directory of Open Access Journals (Sweden)

Américo Hossne

2004-01-01

Full Text Available El conocimiento de las propiedades físicas de los suelos agrícolas y bióticos proporciona información para el manejo de equipos agrícolas, procesos de compactación y la labranza convencional y conservacionista. A medida que la humedad edáfica aumenta, genera diversos estados del suelo; e.g. una menor interacción entre partículas adyacentes y un comportamiento que se aproxima al del líquido. El inicio de la sensibilidad de compactación, parece ser el límite plástico del suelo bajo una bien definida energía de compactación. El objetivo general, de este estudio fue caracterizar sistemáticamente, con las implicaciones de ingeniería posibles, los suelos agrícolas de sabana del Estado Monagas de Venezuela. Los objetivos específicos consistieron en determinar: a- los límites de Atterberg; y b- el índice de plasticidad y friabilidad. Para ello se utilizó los procedimientos de laboratorio de Mecánica de Suelos: ASTM D427-61 para el límite de contracción, ASTM D424-59 para el límite plástico y ASTM 423-66 para el límite líquido, de un suelo de sabana en muestras aleatorias a las profundidades de 0-15, 15-30, 30-45 y 45-60 cm. Se utilizó el análisis de regresión para interpretar la proporción de la variancia entre parámetros. Los resultados indicaron valores de: límite de contracción de 4,22–5,20%, límite plástico de 12,92–14,04%, límite líquido de 16,94–19,43%, índice de plasticidad de 3,59–5,78% e índice de friabilidad de 8,63–8,84%. Se concluye que los valores concuerdan con la bibliografía y el rango de uso agrícola se encuentra entre 8% y 15% para el suelo en estudio.

Preparation and characterization of Al{sub 2}O{sub 3} coating by MOD method on CLF-1 RAFM steel

Energy Technology Data Exchange (ETDEWEB)

Wang, L. [Key Laboratory of Radiation Physics and Technology (Sichuan University), Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064 (China); Yang, J.J., E-mail: jjyang@scu.edu.cn [Key Laboratory of Radiation Physics and Technology (Sichuan University), Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064 (China); Feng, Y.J. [Southwestern Institute of Physics, Chengdu 614000 (China); Li, F.Z.; Liao, J.L.; Yang, Y.Y. [Key Laboratory of Radiation Physics and Technology (Sichuan University), Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064 (China); Feng, K.M. [Southwestern Institute of Physics, Chengdu 614000 (China); Liu, N. [Key Laboratory of Radiation Physics and Technology (Sichuan University), Ministry of Education, Institute of Nuclear Science and Technology, Sichuan University, Chengdu 610064 (China)

2017-04-15

Metal organic decomposition (MOD) method was proposed to prepare Al{sub 2}O{sub 3} TPB coatings on CLF-1 RAFM steel. A comprehensive characterization of SEM, XPS, and XRD demonstrated the formation of Al{sub 2}O{sub 3} coatings. The effect of the preparation parameters, including annealing temperature T{sub a}, withdrawal speed V{sub w} and immersion time t{sub i} on the microstructure and properties of the coatings was investigated. It showed that amorphous aluminum oxide coating began to transform to γ-Al{sub 2}O{sub 3} at temperature of T{sub a} = 600 °C. The Al{sub 2}O{sub 3} coating with T{sub a} = 700 °C and T{sub b} = 500 °C performed the best crystallization feature. The hardness of the coatings gradually increased with increasing V{sub w}, while the corrosion resistance exhibited a reverse trend. Meanwhile, the nanohardness and corrosion resistance of the coating with t{sub i} = 300 s was improved as compared to the coating with t{sub i} = 0 s. Moreover, the effect of particle size and substrate oxidation on the mechanical property and corrosion resistance of the coatings was discussed. - Highlights: •MOD method was proposed to prepare Al{sub 2}O{sub 3} TPB on CLF-1 RAFM steel. •Effect of preparation parameters on the coating microstructure and properties was studied preliminary. •High quality MOD coating can be developed by multi-baking process.

Deposition of selenium coatings on beryllium foils. Revision 1

International Nuclear Information System (INIS)

Erikson, E.D.; Tassano, P.L.; Reiss, R.H.; Griggs, G.E.

1984-01-01

A technique for preparing selenium films on 50.8 micrometers thick beryllium foils is described. The selenium was deposited in vacuum from a resistance heated evaporation source. A water-cooled enclosure was used to minimize contamination of the vacuum system and to reduce the exposure of personnel to toxic and obnoxious materials. Profilometry measurements of the coatings indicated selenium thicknesses of 5.5, 12.9, 37.5, 49.8 and 74.5 micrometers. The control of deposition rate and of coating thickness was facilitated using a commercially available closed-loop programmable deposition controller. The x-ray transmission of the coated substrates was measured using a tritiated zirconium source. The transmissivities of the film/substrate combination are presented for the range of energies from 4 to 20 keV

The long term storage of advanced gas-cooled reactor (AGR) fuel

International Nuclear Information System (INIS)

Standring, P.N.

1999-01-01

The approach being taken by BNFL in managing the AGR lifetime spent fuel arisings from British Energy reactors is given. Interim storage for up to 80 years is envisaged for fuel delivered beyond the life of the Thorp reprocessing plant. Adopting a policy of using existing facilities, to comply with the principles of waste minimisation, has defined the development requirements to demonstrate that this approach can be undertaken safely and business issues can be addressed. The major safety issues are the long term integrity of both the fuel being stored and structure it is being stored in. Business related issues reflect long term interactions with the rest of the Sellafield site and storage optimisation. Examples of the development programme in each of these areas is given. (author)

Characterisation of AGR fuel cladding alloy using secondary ion mass spectrometry

International Nuclear Information System (INIS)

Allen, G.C.; Sparry, R.P.; Wild, R.K.

1987-08-01

Uranium dioxide fuel used in the Advanced Gas Cooled Reactor (AGR) is contained in a ribbed can of 20wt%Cr/25wt%Ni/Nb stabilised steel. Laboratory circumstances, spall during thermal cycling. To date it has been difficult to identify active material originating from the oxidation product of the cladding alloy in the cooling circuit. In an attempt to solve this problem we have set out to characterise fully a sample of oxide from this source and work is in progress to obtain suitable oxide samples from the surface of a 20%Cr/25%Ni/Nb stainless steel. In view of its high sensitivity and the ability to obtain chemical information from relatively small areas we have sought to use Secondary Ion Mass Spectroscopy (SIMS). (author)

Clinical analysis of intravitreal injection of Conbercept combined with 532-laser treating Coats disease in adulthood

Directory of Open Access Journals (Sweden)

Li Jiang

2017-07-01

Full Text Available AIM: To analyze clinical observation and the efficiency of intravitreal conbercept combined with 532-laser on Coats disease in adulthood. METHODS: This was an retrospective analysis. Six eyes from 6 patients(5 males and 1 femalewith coats disease diagnosed by fundus fluorescein angiography(FFAand optical coherence tomography(OCTwere enrolled. Before the injection, best-corrected visual acuity(BCVAof early treatment of diabetic retinopathy study(ETDRS, non-contact tonometer, ophthalmoscope, fundus photography, FFA, and OCT were examined. The initial average visual acuity(ETDRS letterswere 51.17±15.15. The initial average central retina thickness(CRTwas 303.30±107.87μm. All affected eyes were treated with intravitreal conbercept 0.05mL(10mg/mLcombined with 532-laser. Patients were followed up for 6 to 12mo, with a mean duration of 7.33±1.26mo. Post-treatment BCVA were compared with baseline using repeat analysis. RESULTS: The mean BCVA showed significant improvement during 1 wk, 1, 3mo post-treatment and the latest follow up(PCONCLUSION: Coats disease in adulthood more likely to have lower symptom and have a better response on treatment. Intravitreal conbercept combined with 532-laser significantly improve visual acuity and absorb the subretina fluid.

Evaluation of irradiated coating material specimens

International Nuclear Information System (INIS)

Lee, Yong Jin; Nam, Seok Woo; Cho, Lee Moon

2007-12-01

Evaluation result of irradiated coating material specimens - Coating material specimens radiated Gamma Energy(Co 60) in air condition. - Evaluation conditions was above 1 X 10 4 Gy/hr, and radiated TID 2.0 X 10 6 Gy. - The radiated coating material specimens, No Checking, Cracking, Flaking, Delamination, Peeling and Blistering. - Coating system at the Kori no. 1 and APR 1400 Nuclear power plant, evaluation of irradiated coating materials is in accordance with owner's requirement(2.0 X 10 6 Gy)

Contaminación y control de las quemas agrícolas en Imperial, California, y Mexicali, Baja California

Directory of Open Access Journals (Sweden)

Margarito Quintero Núñez

2008-01-01

Full Text Available La quema de residuos agrícolas en los valles de Mexicali e Imperial, separados por una línea divisoria, constituye una fuente importante de emisión de contaminantes al aire, de compuestos como el metano (CH4, monóxido de carbono (CO, bióxido de nitrógeno (NO2, hidrocarburos (NMHC y partículas menores a 10 micras (PM10. Para abordar el problema de los humos agrícolas se debe considerar la cuenca atmosférica común, formada por ambos valles, que comparten un clima extremoso cálido y seco, con menos de 80 mm anuales de lluvia, y basan su economía en la agricultura, y el de Mexicali además en la industria manufacturera y otras actividades. En Mexicali, lo que se quema es sobre todo residuos de trigo y en menor proporción de cebada, cártamo y maíz. Los daños a la salud ocasionados por las emisiones de PM10 son significativos en ambos valles

Effect of Simulated High Hydrogen Content Combustion Environments on Abradable Properties of Ceramic Turbine Coatings

Science.gov (United States)

Basu Majumder, Madhura

Air plasma sprayed (APS) abradable coatings are used in the turbine hot section to reduce the stator-rotor gap, minimizing gas leakage. These coatings are designed to exhibit controlled removal of material in thin layers when the turbine blades sweep through the coating, which protects the mechanical integrity of the turbine blade. In an effort to lower CO2 emissions, high H2 content fuel is being explored. This change in chemical composition of the fuel may affect the microstructure, abradability and durability of the coatings at turbine operational temperatures. The presence of high water vapor in the combustion chamber leads to accelerated degradation of the sacrificial coating materials. In this work, zirconia based composite materials with a machinable phase and varied porosity have been used to study microstructural evolution, thermal and chemical stability of the phases and abradable characteristics of baseline coating systems in both humid and dry environments. Investigation of the mechanisms that control the removal of materials and performance of abradable coatings through thermo-mechanical tests will be discussed.

Effect of Suspension Plasma-Sprayed YSZ Columnar Microstructure and Bond Coat Surface Preparation on Thermal Barrier Coating Properties

Science.gov (United States)

Bernard, Benjamin; Quet, Aurélie; Bianchi, Luc; Schick, Vincent; Joulia, Aurélien; Malié, André; Rémy, Benjamin

2017-08-01

Suspension plasma spraying (SPS) is identified as promising for the enhancement of thermal barrier coating (TBC) systems used in gas turbines. Particularly, the emerging columnar microstructure enabled by the SPS process is likely to bring about an interesting TBC lifetime. At the same time, the SPS process opens the way to a decrease in thermal conductivity, one of the main issues for the next generation of gas turbines, compared to the state-of-the-art deposition technique, so-called electron beam physical vapor deposition (EB-PVD). In this paper, yttria-stabilized zirconia (YSZ) coatings presenting columnar structures, performed using both SPS and EB-PVD processes, were studied. Depending on the columnar microstructure readily adaptable in the SPS process, low thermal conductivities can be obtained. At 1100 °C, a decrease from 1.3 W m-1 K-1 for EB-PVD YSZ coatings to about 0.7 W m-1 K-1 for SPS coatings was shown. The higher content of porosity in the case of SPS coatings increases the thermal resistance through the thickness and decreases thermal conductivity. The lifetime of SPS YSZ coatings was studied by isothermal cyclic tests, showing equivalent or even higher performances compared to EB-PVD ones. Tests were performed using classical bond coats used for EB-PVD TBC coatings. Thermal cyclic fatigue performance of the best SPS coating reached 1000 cycles to failure on AM1 substrates with a β-(Ni,Pt)Al bond coat. Tests were also performed on AM1 substrates with a Pt-diffused γ-Ni/γ'-Ni3Al bond coat for which more than 2000 cycles to failure were observed for columnar SPS YSZ coatings. The high thermal compliance offered by both the columnar structure and the porosity allowed the reaching of a high lifetime, promising for a TBC application.

Análisis de redes sociales para catalizar la innovación agrícola: de los vínculos directos a la integración y radialidad

Directory of Open Access Journals (Sweden)

Norman Aguilar-Gallegos

2016-07-01

Full Text Available Se analizan los efectos de las interacciones, directas e indirectas, entre agricultores y otros actores relevantes en el intercambio de información y conocimiento para la innovación agrícola. Los datos se obtuvieron al preguntar a 120 agricultores «¿de quién aprende y/o a quién recurre para obtener información o conocimiento de cuestiones técnicas y productivas en torno a su unidad de producción?». Se emplean indicadores del análisis de redes sociales para proponer lineamientos que permitan catalizar la innovación agrícola. Los resultados confirman la importancia de los vínculos indirectos, pues estos permiten que los agricultores alcancen mejor información de fuentes externas. Se recomienda que los programas encaminados a promover la innovación agrícola consideren la interacción preexistente en las redes de los agricultores.

The Influence of Nano-Fibrillated Cellulose as a Coating Component in Paper Coating

Directory of Open Access Journals (Sweden)

Yaxi Xu

2016-03-01

Full Text Available This work investigates nano-fibrillated cellulose (NFC as a component in mineral pigment paper coating. In this work, bleached Eucalyptus pulp was pretreated by TEMPO (2,2,6,6-tetramethyl-1-piperdinyloxy-mediated oxidation. The oxidized pulp was then isolated to obtain NFC by sonication. Aqueous coating colors consisting of calcium carbonate, clay, carboxylated butadiene-styrene latex, additives, and NFC were prepared. The rheology of the coating colors and the surface properties of paper coated with NFC containing coating colors were determined. The rheological properties allowed NFC to be used in small amounts under laboratory conditions. Nano-fibrillated cellulose was found to improve the surface strength and smoothness of the coated paper. The water resistance of coated paper, on the other hand, decreased because of the hydrophilicity of NFC.

Spent Nuclear Fuel Project technical baseline document. Fiscal year 1995: Volume 1, Baseline description

International Nuclear Information System (INIS)

Womack, J.C.; Cramond, R.; Paedon, R.J.

1995-01-01

This document is a revision to WHC-SD-SNF-SD-002, and is issued to support the individual projects that make up the Spent Nuclear Fuel Project in the lower-tier functions, requirements, interfaces, and technical baseline items. It presents results of engineering analyses since Sept. 1994. The mission of the SNFP on the Hanford site is to provide safety, economic, environmentally sound management of Hanford SNF in a manner that stages it to final disposition. This particularly involves K Basin fuel, although other SNF is involved also

10 CFR 850.20 - Baseline beryllium inventory.

Science.gov (United States)

2010-01-01

... 10 Energy 4 2010-01-01 2010-01-01 false Baseline beryllium inventory. 850.20 Section 850.20 Energy... Baseline beryllium inventory. (a) The responsible employer must develop a baseline inventory of the... inventory, the responsible employer must: (1) Review current and historical records; (2) Interview workers...

Baseline tests for arc melter vitrification of INEL buried wastes. Volume 1: Facility description and summary data report

International Nuclear Information System (INIS)

Oden, L.L.; O'Connor, W.K.; Turner, P.C.; Soelberg, N.R.; Anderson, G.L.

1993-01-01

This report presents field results and raw data from the Buried Waste Integrated Demonstration (BWID) Arc Melter Vitrification Project Phase 1 baseline test series conducted by the Idaho National Engineering Laboratory (INEL) in cooperation with the U.S. Bureau of Mines (USBM). The baseline test series was conducted using the electric arc melter facility at the USBM Albany Research Center in Albany, Oregon. Five different surrogate waste feed mixtures were tested that simulated thermally-oxidized, buried, TRU-contaminated, mixed wastes and soils present at the INEL. The USBM Arc Furnace Integrated Waste Processing Test Facility includes a continuous feed system, the arc melting furnace, an offgas control system, and utilities. The melter is a sealed, 3-phase alternating current (ac) furnace approximately 2 m high and 1.3 m wide. The furnace has a capacity of 1 metric ton of steel and can process as much as 1,500 lb/h of soil-type waste materials. The surrogate feed materials included five mixtures designed to simulate incinerated TRU-contaminated buried waste materials mixed with INEL soil. Process samples, melter system operations data and offgas composition data were obtained during the baseline tests to evaluate the melter performance and meet test objectives. Samples and data gathered during this program included (a) automatically and manually logged melter systems operations data, (b) process samples of slag, metal and fume solids, and (c) offgas composition, temperature, velocity, flowrate, moisture content, particulate loading and metals content. This report consists of 2 volumes: Volume I summarizes the baseline test operations. It includes an executive summary, system and facility description, review of the surrogate waste mixtures, and a description of the baseline test activities, measurements, and sample collection. Volume II contains the raw test data and sample analyses from samples collected during the baseline tests

Effect of applied bias voltage on corrosion-resistance for TiC1-xNx and Ti1-xNbxC1-yNy coatings

International Nuclear Information System (INIS)

Caicedo, J.C.; Amaya, C.; Yate, L.; Aperador, W.; Zambrano, G.; Gomez, M.E.; Alvarado-Rivera, J.; Munoz-Saldana, J.; Prieto, P.

2010-01-01

Corrosion-resistance behavior of titanium carbon nitride (Ti-C-N) and titanium niobium carbon nitride (Ti-Nb-C-N) coatings deposited onto Si(1 0 0) and AISI 4140 steel substrates via r.f. magnetron sputtering process was analyzed. The coatings in contact with a solution of sodium chloride at 3.5% were studied by Tafel polarization curves and impedance spectroscopy methods (EIS). Variations of the bias voltage were carried out for each series of deposition to observe the influence of this parameter upon the electrochemical properties of the coatings. The introduction of Nb in the ternary Ti-C-N film was evaluated via X-ray diffraction (XRD) analysis. The structure was characterized by using Raman spectroscopy to identify ternary and quaternary compounds. Surface corrosion processes were characterized using optical microscopy and scanning electron microscopy (SEM). XRD results show conformation of the quaternary phase, change in the strain of the film, and lattice parameter as the effect of the Nb inclusion. The main Raman bands were assigned to interstitial phases and 'impurities' of the coatings. Changes in Raman intensities were attributed to the incorporation of niobium in the Ti-C-N structure and possibly to resonance enhancement. Finally, the corrosion data obtained for Ti-C-N were compared with the results of corrosion tests of Ti-Nb-C-N coating. The results obtained showed that the incorporation of niobium to Ti-C-N coatings led to an increase in the corrosion-resistance. On another hand, an increase in the bias voltage led to a decrease in the corrosion-resistance for both Ti-C-N and Ti-Nb-C-N coatings.

Las actividades complementarias de las explotaciones agrícolas peruanas

Directory of Open Access Journals (Sweden)

2002-01-01

Full Text Available La diversification des sources de revenu des exploitations agricoles est une question cruciale pour le bien être des populations rurales. En effet, toute utilisation supplémentaire du travail en milieu rural pour des activités autres que celles directement liées à l’exploitation agricole peut contribuer à augmenter les revenus, même modestement. Cet article montre que malgré le potentiel que représentent les activités complémentaires des exploitations agricoles tant en termes de création d’emplois que de revenus, elles sont encore un domaine peu compris de l’économie rurale. Cette faiblesse provient à la fois de l’hétérogénéité de ces activités qui est à la source de nombreuses confusions conceptuelles et des lacunes des statistiques nationales disponibles qui n’enregistrent pas ces activités de manière adéquate. En dépit de ces difficultés, cet article tente de donner un aperçu de l’importance et des caractéristiques des activités complémentaires des exploitations agricoles péruviennes. Quatre conclusions principales émergent de l’ensemble des résultats présentés : la sous-estimation indubitable de ces activités donc des revenus qui en découlent la part significative qu’occupe l’agriculture dans l’ensemble des activités complémentaires, la concentration de ces activités dans deux ou trois secteurs, la relative stabilité de leur distribution selon les secteurs dans le temps et dans l’espace, une division du travail assez marquée entre les hommes et les femmes. La diversificación de las fuentes de ingresos de las explotaciones agrícolas es un asunto crucial para el bienestar de las poblaciones rurales. De hecho, en el medio rural, todo trabajo adicional en actividades distintas a las directamente relacionadas con la explotación agrícola puede contribuir al aumento de los ingresos, aun en forma modesta. Este trabajo muestra que, pese a su potencial en términos de generación de empleos e

Agricultural Labor Demand in Chile: A Cointegration Approach Demanda por Trabajo Agrícola en Chile: Un Enfoque de Cointegración

Directory of Open Access Journals (Sweden)

Rodrigo Saens N

2008-12-01

Full Text Available International evidence shows that the positive relationship between product and agricultural labor has weakened during the last 30 years, especially in emergent economies. Chilean agriculture has not been left out of this phenomenon The main purpose of this reseach was to estimate the causality relationships that govern the product, employment and salaries in the Chilean silviculture-agricultural-livestock sector, using a cointegration approach. Quarterly data from the 1996-2005 period were employed to estimate agricultural labor demand. A Cobb-Douglas agricultural production function was employed and from it were derived the minimum cost function and the labor demand as bases of this study; the latter was approximated log-linearly to find different measures of elasticity. The main results shows that the estimated demand for agricultural labor has long-run employment-product and employment-salary elasticities of 0.38 and -0.88, respectively. An important conclusion suggests that, compared with the employment-product and employment-salary elasticities of labor demand on the aggregated level, agricultural employment in the long run results less sensitive to changes in the product, but more sensitive to changes in salaries.La evidencia internacional muestra que la relación positiva entre producto y empleo agrícola se ha debilitado en los últimos 30 años, especialmente en economías emergentes. La agricultura en Chile no ha estado al margen de este fenómeno. El objetivo principal de esta investigación fue estimar las relaciones de causalidad que rigen al producto, el empleo y los salarios en el sector silvoagropecuario chileno, utilizando un enfoque de cointegración. Para la estimación de la demanda por trabajo agrícola se utilizaron datos trimestrales del período 1996 a 2005. Se utilizó una función de producción agrícola tipo Cobb-Douglas, a partir de la cual se derivó la función de costo mínimo y la demanda por trabajo base de

Progress in Solving the Elusive Ag Transport Mechanism in TRISO Coated Particles: What is new?

Energy Technology Data Exchange (ETDEWEB)

Isabella Van Rooyen

2014-10-01

The TRISO particle for HTRs has been developed to an advanced state where the coating withstands internal gas pressures and retains fission products during irradiation and under postulated accidents. However, one exception is Ag that has been found to be released from high quality TRISO coated particles when irradiated and can also during high temperature accident heating tests. Although out- of- pile laboratory tests have never hither to been able to demonstrate a diffusion process of Ag in SiC, effective diffusion coefficients have been derived to successfully reproduce measured Ag-110m releases from irradiated HTR fuel elements, compacts and TRISO particles It was found that silver transport through SiC does not proceed via bulk volume diffusion. Presently grain boundary diffusion that may be irradiation enhanced either by neutron bombardment or by the presence of fission products such as Pd, are being investigated. Recent studies of irradiated AGR-1 TRISO fuel using scanning transmission electron microscopy (STEM), transmission kukuchi diffraction (TKD) patterns and high resolution transmission electron microscopy (HRTEM) have been used to further the understanding of Ag transport through TRISO particles. No silver was observed in SiC grains, but Ag was identified at triple-points and grain boundaries of the SiC layer in the TRISO particle. Cadmium was also found in some of the very same triple junctions, but this could be related to silver behavior as Ag-110m decays to Cd-110. Palladium was identified as the main constituent of micron-sized precipitates present at the SiC grain boundaries and in most SiC grain boundaries and the potential role of Pd in the transport of Ag will be discussed.

Mecanización agrícola, empleo y migración en el norte de Tamaulipas

Directory of Open Access Journals (Sweden)

José Luis Contreras Valenzuela

1986-05-01

Full Text Available El objetivo del presente trabajo es analizar el modelo de desarrollo agrícola recientemente adoptado en los distritos de riego del norte de Tamaulipas, y los efectos sobre el empleo y la migración de la población rural. Dicho análisis se efectuará a partir de dos premisas fundamentales: una de ellas es la internacionalización del proceso productivo que se manifiesta con la presencia de una nueva división internacional del trabajo y lo que en este ensayo es llamada economía campesina, que fue la fuente primaria de la acumulación de capital de la agricultura mexicana, la cual jugará un papel importante para la acumulación de capital de la agricultura de los Estados Unidos de América, mediante la oferta de fuerza de trabajo agrícola barata, permitiendo el desarrollo de la agricultura comercial, modelo que ahora se ha volcado sobre la economía campesina condenándola a su desaparición como forma de subsistencia de la población rural, a quien expulsa de sus unidades de producción mediante el acaparamiento y el rentismo.

Biorremediación de un suelo agrícola impactado con aceite residual automotriz

OpenAIRE

Pasaye Anaya, Lizbeth

2011-01-01

El aceite residual automotriz (ARA) derivado del uso de automotores es una mezcla de hidrocarburos (HC) alifáticos, aromáticos y otros que en el suelo impide la actividad microbiana para el reciclaje de elementos esenciales para la vida. El objetivo de este trabajo fue analizar la biorremediación (BR) por bioestimulación (BS) de un suelo agrícola impactado con ARA. Para ello, el suelo contaminado con la mezcla de HC se biorremedió por BS con una solución mineral (SM), lombricomposta (LC) y ab...

Agricultura familiar e as rendas não-agrícolas na Região Metropolitana de Porto Alegre : um estudo de caso dos municípios de Dois Irmãos e Ivoti - RS

OpenAIRE

Marco Antonio Verardi Fialho

2000-01-01

Esta estudo discute a importância das rendas não-agrícolas na composição da renda total dos agricultores familiares de uma região fortemente marcada pela pluriatividade de seus produtores rurais. Os dados utilizados neste estudo foram obtidos a partir de uma pesquisa de campo realizada junto a 57 agricultores familiares dos municípios de Dois Irmãos e Ivoti, RS. A metodologia utilizada consistiu na identificação e quantificação das rendas agrícolas e não-agrícolas bem como na caracterização d...

A long baseline global stereo matching based upon short baseline estimation

Science.gov (United States)

Li, Jing; Zhao, Hong; Li, Zigang; Gu, Feifei; Zhao, Zixin; Ma, Yueyang; Fang, Meiqi

2018-05-01

In global stereo vision, balancing the matching efficiency and computing accuracy seems to be impossible because they contradict each other. In the case of a long baseline, this contradiction becomes more prominent. In order to solve this difficult problem, this paper proposes a novel idea to improve both the efficiency and accuracy in global stereo matching for a long baseline. In this way, the reference images located between the long baseline image pairs are firstly chosen to form the new image pairs with short baselines. The relationship between the disparities of pixels in the image pairs with different baselines is revealed by considering the quantized error so that the disparity search range under the long baseline can be reduced by guidance of the short baseline to gain matching efficiency. Then, the novel idea is integrated into the graph cuts (GCs) to form a multi-step GC algorithm based on the short baseline estimation, by which the disparity map under the long baseline can be calculated iteratively on the basis of the previous matching. Furthermore, the image information from the pixels that are non-occluded under the short baseline but are occluded for the long baseline can be employed to improve the matching accuracy. Although the time complexity of the proposed method depends on the locations of the chosen reference images, it is usually much lower for a long baseline stereo matching than when using the traditional GC algorithm. Finally, the validity of the proposed method is examined by experiments based on benchmark datasets. The results show that the proposed method is superior to the traditional GC method in terms of efficiency and accuracy, and thus it is suitable for long baseline stereo matching.

Low Thermal Conductivity, High Durability Thermal Barrier Coatings for IGCC Environments

Energy Technology Data Exchange (ETDEWEB)

Jordan, Eric [Univ. of Connecticut, Storrs, CT (United States); Gell, Maurice [Univ. of Connecticut, Storrs, CT (United States)

2015-01-15

Advanced thermal barrier coatings (TBC) are crucial to improved energy efficiency in next generation gas turbine engines. The use of traditional topcoat materials, e.g. yttria-stabilized zirconia (YSZ), is limited at elevated temperatures due to (1) the accelerated undesirable phase transformations and (2) corrosive attacks by calcium-magnesium-aluminum-silicate (CMAS) deposits and moisture. The first goal of this project is to use the Solution Precursor Plasma Spray (SPPS) process to further reduce the thermal conductivity of YSZ TBCs by introducing a unique microstructural feature of layered porosity, called inter-pass boundaries (IPBs). Extensive process optimization accompanied with hundreds of spray trials as well as associated SEM cross-section and laser-flash measurements, yielded a thermal conductivity as low as 0.62 Wm⁻¹K⁻¹ in SPPS YSZ TBCs, approximately 50% reduction of APS TBCs; while other engine critical properties, such as cyclic durability, erosion resistance and sintering resistance, were characterized to be equivalent or better than APS baselines. In addition, modifications were introduced to SPPS TBCs so as to enhance their resistance to CMAS under harsh IGCC environments. Several mitigation approaches were explored, including doping the coatings with Al₂O₃ and TiO₂, applying a CMAS infiltration-inhibiting surface layer, and filling topcoat cracks with blocking substances. The efficacy of all these modifications was assessed with a set of novel CMAS-TBC interaction tests, and the moisture resistance was tested in a custom-built high-temperature moisture rig. In the end, the optimal low thermal conductivity TBC system was selected based on all evaluation tests and its processing conditions were documented. The optimal coating consisted on a thick inner layer of YSZ coating made by the SPPS process having a thermal conductivity 50% lower than standard YSZ coatings topped with a high temperature tolerant CMAS resistant gadolinium

Effect of sealer coating and storage methods on the surface roughness of soft liners.

Science.gov (United States)

Usta Kutlu, Ilknur; Yanikoğlu, Nuran Dinckal; Kul, Esra; Duymuş, Zeynep Yesïl; Sağsöz, Nurdan Polat

2016-03-01

A soft lining is applied under a removable prosthesis for various reasons. The porosity of the lining material may increase colonization by microorganisms and cause tissue inflammation. The purpose of this in vitro study was to evaluate the effect of sealer coating on the surface roughness of soft lining materials under 4 different conditions. A total of 125 specimens were prepared. One high-temperature silicone-based soft lining material and 2 room-temperature-polymerized soft lining materials (1 silicone-based and 1 methacrylate-based) were used. Twenty-five specimens of each room-temperature soft lining material were coated with 2 layers of surface sealer. Additionally, 5 specimens of each material were stored in either distilled water, Coca-Cola, denture cleanser, saliva, or air. The surface roughness was measured at baseline and after 1, 7, 14, and 28 days. Surface roughness values were analyzed with repeated measures analysis of variance, and the Bonferroni multiple comparison test was performed using time-dependent groups and storage methods. In the time-dependent groups, methacrylate-based sealer-coated soft liners exhibited a significant increase in roughness (1.74-2.09 μm, P.05). Therefore, the sealer coating was not effective in reducing surface roughness. Among the time-dependent storage methods, the denture cleanser exhibited an almost significant increase in roughness (1.83-1.99 μm, P=.054). Coca-Cola and artificial saliva did not show a significant difference (P>.05). However, a significant decrease in roughness was found with distilled water (P=.02) and air (P<.001). Statistically significant differences in surface roughness were found among the different types of soft liners. The sealer coating had no significant effect, and denture cleanser slightly increased the surface roughness. Contrary to expectations, the roughness did not increase in all groups over time. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry

Standard Test Method for Mechanical Hydrogen Embrittlement Evaluation of Plating/Coating Processes and Service Environments

CERN Document Server

American Society for Testing and Materials. Philadelphia

2010-01-01

1.1 This test method describes mechanical test methods and defines acceptance criteria for coating and plating processes that can cause hydrogen embrittlement in steels. Subsequent exposure to chemicals encountered in service environments, such as fluids, cleaning treatments or maintenance chemicals that come in contact with the plated/coated or bare surface of the steel, can also be evaluated. 1.2 This test method is not intended to measure the relative susceptibility of different steels. The relative susceptibility of different materials to hydrogen embrittlement may be determined in accordance with Test Method F1459 and Test Method F1624. 1.3 This test method specifies the use of air melted AISI E4340 steel per SAE AMS-S-5000 (formerly MIL-S-5000) heat treated to 260 – 280 ksi (pounds per square inch x 1000) as the baseline. This combination of alloy and heat treat level has been used for many years and a large database has been accumulated in the aerospace industry on its specific response to exposure...

Analysis on Propagation Characteristics and Experimental Verification of A1 Circumferential Waves in Nuclear Fuel Rods Coated with Oxide Layers

International Nuclear Information System (INIS)

Joo, Young Sang; Jung, Hyun Kyu; Cheong, Yong Moo; Ih, Jeong Guon

1999-01-01

The resonance scattering of acoustic waves from the cylindrical shells of nuclear fuel rods coated with oxide layers has been theoretically modeled and numerically analyzed for the propagation characteristics of the circumferential waves. The normal mode solutions of the scattering pressure of the coated shells have been obtained. The pure resonance components have been isolated using the newly proposed inherent background coefficients. The propagation characteristics of resonant circumferential waves for the shells coated with oxide layers are affected by the presence and the thickness of an oxide layer. The characteristics have been experimentally confirmed through the method of isolation and identification of resonances. The change of the phase velocity of the A 1 circumferential wave mode for the coated shell is negligible at the specified partial waves in spite of the presence of the oxide layer and the increase in coating thickness. Utilizing the invariability characteristics of the phase velocity of the A 1 mode, the oxide layer thickness of the coated shells can be estimated. A new nondestructive technique for the relative measurement of the coating thickness of coated shells has been proposed

Flow Injection Potentiometric Determination of Cd2+ Ions Using a Coated Graphite Plasticized PVC-Membrane Electrode Based on 1, 3-Bis(2-cyanobenzene)triazene.

Science.gov (United States)

Shamsipur, Mojtaba; Sahari, Shokat; Payehghadr, Mahmood; Alizadeh, Kamal

2011-09-01

1, 3-Bis(2-cyanobenzene)triazene, L, was used as a suitable ionophore for the fabrication of a new PVC-based polymeric membrane coated graphite electrode for selective sensing of Cd2+ ion. The electrode exhibited a selective linear Nernstian response to Cd2+ ion at an optimal pH range of 6-9 with a limit of detection of 8.0 × 10-6 M and a fast response time of about 2 s. The electrode was used as a proper detection system in flow-injection potentiometry of cadmium ion and resulted in well defined peaks for cadmium ions with stable baseline, excellent reproducibility and high sampling rates of over 100 injections per hour. It showed good stability, reproducibility and fast response time. The practical utility of the proposed system has also been reported.

Dynamic interactions of the asialoglycoprotein receptor subunits with coated pits. Enhanced interactions of H2 following association with H1.

Science.gov (United States)

Katzir, Z; Nardi, N; Geffen, I; Fuhrer, C; Henis, Y I

1994-08-26

Lateral mobility studies comparing native and mutated membrane proteins, combined with treatments that alter clathrin lattice structure, can measure membrane protein-coated pit interactions in intact cells (Fire, E., Zwart, D., Roth, M. G., and Henis, Y. I. (1991) J. Cell Biol. 115, 1585-1594). We applied this approach to study the interactions of the H1 and H2 human asialoglycoprotein receptor subunits with coated pits. The lateral mobilities of singly expressed and coexpressed H1 and H2B (the H2 species that reaches the cell surface) were measured by fluorescence photobleaching recovery. They were compared with mutant proteins, H1(5A) (Tyr-5 replaced by Ala) and H2(5A) (Phe-5 replaced by Ala). While the mobile fractions of H1, H2B, and their mutants were similar, the lateral diffusion rate (measured by D, the lateral diffusion coefficient) was significantly slower for H1, whether expressed alone or with H2B. Coexpression with H1 reduced D of H2B to that of H1. Disruption of the clathrin lattices by hypertonic medium elevated D of H1, H1(5A), H2B, and H2(5A) to the same final level, without affecting their mobile fractions. Cytosol acidification, which retains altered clathrin lattices attached to the membrane and prevents coated vesicle formation, immobilized part of the H1 molecules, reflecting stable entrapment in "frozen" coated pits. H1(5A), H2B, and H2(5A) were not affected; however, coexpression of H2B with H1 conferred the sensitivity to cytosol acidification on H2B. Our results suggest that H1 lateral mobility is inhibited by dynamic interactions with coated pits in which Tyr-5 is involved. H2B resembles H1(5A) rather than H1, and its interactions with coated pits are weaker; efficient interaction of H2B with coated pits depends on complex formation with H1.

High temperature oxidation behavior of hafnium modified NiAl bond coat in EB-PVD thermal barrier coating system

Energy Technology Data Exchange (ETDEWEB)

Guo Hongbo; Sun Lidong; Li Hefei [Department of Material Science and Engineering, Beijing University of Aeronautics and Astronautics, No.37 Xueyuan Road, Beijing 100083 (China); Gong Shengkai [Department of Material Science and Engineering, Beijing University of Aeronautics and Astronautics, No.37 Xueyuan Road, Beijing 100083 (China)], E-mail: gongsk@buaa.edu.cn

2008-06-30

NiAl coatings doped with 0.5 at.% and 1.5 at.% Hf were produced by co-evaporation of NiAl and Hf ingots by electron beam physical vapor deposition (EB-PVD), respectively. The addition of 0.5 at.% Hf significantly improved the cyclic oxidation resistance of the NiAl coating. The TGO layer in the 1.5 at.% Hf doped NiAl coating is straight; while that in the 0.5 at.% Hf doped coating became undulated after thermal cycling. The doped NiAl thermal barrier coatings (TBCs) revealed improved thermal cycling lifetimes at 1423 K, compared to the undoped TBC. Failure of the 0.5 at.% Hf doped TBC occurred by cracking at the interface between YSZ topcoat and bond coat, while the 1.5 at.% Hf doped TBC cracked at the interface between bond coat and substrate.

Baseline Anthropometric and Metabolic Parameters Correlate with Weight Loss in Women 1-Year After Laparoscopic Roux-En-Y Gastric Bypass.

Science.gov (United States)

Sans, Arnaud; Bailly, Laurent; Anty, Rodolphe; Sielezenef, Igor; Gugenheim, Jean; Tran, Albert; Gual, Philippe; Iannelli, Antonio

2017-11-01

In this study, we explored in a prospective cohort of morbidly obese women undergoing laparoscopic Roux-en-Y gastric bypass (LRYGP) correlations between baseline anthropometrics, metabolic parameters, resting energy expenditure (REE), body composition, and 1-year % excess body mass index loss (%EBMIL). We also investigated risk factors for insufficient %EBMIL. One hundred three consecutive women were prospectively evaluated at baseline (age 40.6 ± 11.2, weight 113.9 kg ± 15.3, BMI 43.3 ± 4.9 kg/m 2 ) and 1 year after LRYGP. Weight, excess weight, brachial circumference, waist circumference, fat mass (FM) and fat-free mass (FFM) (measured with bioelectrical impedance analysis), REE, inflammation, insulin resistance, and lipid disturbances were determined before and 1 year after LRYGP. At 1 year, mean weight loss was 39.8 kg ± 11.7 and mean EBMIL was 15.2 kg/m 2  ± 4.2. Mean %EBMIL was 86% ± 21% (range 30-146%). Baseline brachial circumference, waist circumference and triceps skinfold thickness decreased significantly at 1 year (P baseline body composition parameters, only preoperative FM was negatively correlated with %EBMIL (r = -0.23; p = 0.02). One year after surgery FM change was negatively correlated with EBMIL% (r = -0.49; P baseline blood glucose level (OR = 1.77; CI 95%: [1.3-2.4]) was the only predictive factor of EBMIL Baseline glucose level may be helpful in identifying poor responders to LRYGBP. NCT02820285y ( https://clinicaltrials.gov/ct2/show/NCT02820285?term=Characterization+of+Immune+Semaphorin+in+Non-Alcoholic+Fatty+Liver+Disease+and+NASH&rank=1 ).

Site Outcomes Baseline Multi Year Work Plan Volume 1, River Corridor Restoration Baseline

International Nuclear Information System (INIS)

Wintczak, T.M.

2001-01-01

The River Corridor Restoration volume is a compilation of Hanford Site scope, which excludes the approximately 194 km 2 Central Plateau. The River Corridor scope is currently contractually assigned to Fluor Hanford, Bechtel Hanford, inc., DynCorp, and Pacific Northwest National Laboratory, and others. The purpose of this project specification is to provide an overall scoping document for the River Corridor Restoration volume, and to provide a link with the overall Hanford Site River Corridor scope. Additionally, this specification provides an integrated and consolidated source of information for the various scopes, by current contract, for the River Corridor Restoration Baseline. It identifies the vision, mission, and goals, as well as the operational history of the Hanford Site, along with environmental setting and hazards

Periprosthetic bone densitometry of the hip: Influence of design and hydroxyapatite coating on regional bone remodeling; 5 year follow-up

International Nuclear Information System (INIS)

Rosenthall

2002-01-01

Aim: To determine bone mineral density changes surrounding two differently designed titanium alloy porous-coated femoral hip prostheses (S-ROM and Multilock) as a function of time. Materials and Methods: The periprosthetic bone regions were defined by the seven Gruen zones. Measurements were obtained by DXA utilizing a dedicated software program (LUNAR ORTH). Inclusion criteria required that the patients were asymptomatic with Harris hip scores >95, showed no radiographic evidence of loosening and that they had primary implants. The protocol specified that bone measurements be obtained within one week after implantation as a baseline reference and at 6 months, 12 months and yearly thereafter. 111 consecutive S-ROM and 65 consecutive Multilock patients were enrolled in this ongoing prospective study. Of the 65 patients with Multilock implants, 25 had a 50 micron thick coating of hydroxyapatite-tricalcium phosphate (HA) sprayed over the porous surface and 40 were without coating. Results: At 6 months the mean BMD of all zones showed a significant decrease relative to the baseline measurement, varying from 6% to 17%. Gruen zones 2 to 6 exhibited variable degrees of recovery by 60 months. The maximum mineral losses were registered proximally in zone 1 (greater trochanter) and zone 7 (calcar and lesser trochanter), which are recognized sites of prosthetic stress shielding. The detailed results at 60 months are presented. In Gruen zone 1 the mineral loss in the S-ROM implant is significantly less the than either Multilock type. Also, mineral loss with Multilock-HA is about 55% less than the Multilock-uncoated. In Gruen zone 7 there is no difference between S-ROM and Multilock-uncoated, but Multilock-HA lost 44% less density than Multilock-uncoated. Conclusion: Regional bone remodeling appears to be related to prosthesis design. HA coating substantially and significantly reduces mineral loss in the proximal porous area; the mechanism is speculative

Aplicación de Lodo de Procesos de Intercambio Iónico como Mitigante de la Sodicidad en un Suelo Agrícola Salino-Sódico

Directory of Open Access Journals (Sweden)

Octavio Armendáriz Alcaraz

2013-09-01

Full Text Available La salinidad y sodicidad en los suelos es un problema que afecta a una gran extensión de campos agrícolas. El sodio en exceso provoca el rompimiento de la estructura del suelo, volviéndolo impermeable, lo que reduce la cantidad de agua que llega a la zona de raíz. Se evaluó la eficiencia de tres dosis (D1= 0.424 g,D2= 1.061g y D3= 1.7 g de un tipo de lodo obtenido de la planta potabilizadora de agua subterránea “La Campiña II” en el tratamiento de un suelo salino-sódico (44.13 g usando columnas de suelo en el laboratorio. Se determinaron las propiedades fisicoquímicas del suelo y del lodo, así como la velocidad final de infiltración (VFI, la conductividad eléctrica (CE y la relación de absorción de sodio (RAS. La adición de este tipo de lodos mejoró significativamente las VFI respecto a las muestras sin recibir tratamiento. La dosis de 1.061 g presentó la mejor velocidad final de infiltración. Se puede concluir que los experimentos utilizando el lodo de la planta “La Campiña II” se obtuvieron resultados que lo hacen atractivo para su uso en suelos agrícolas con problemas de sodicidad.

Mitigation of chromium poisoning of cathodes in solid oxide fuel cells employing CuMn1.8O4 spinel coating on metallic interconnect

Science.gov (United States)

Wang, Ruofan; Sun, Zhihao; Pal, Uday B.; Gopalan, Srikanth; Basu, Soumendra N.

2018-02-01

Chromium poisoning is one of the major reasons for cathode performance degradation in solid oxide fuel cells (SOFCs). To mitigate the effect of Cr-poisoning, a protective coating on the surface of interconnect for suppressing Cr vaporization is necessary. Among the various coating materials, Cu-Mn spinel coating is considered to be a potential candidate due to their good thermal compatibility, high stability and good electronic conductivity at high temperature. In this study, Crofer 22 H meshes with no protective coating, those with commercial CuMn2O4 spinel coating and the ones with lab-developed CuMn1.8O4 spinel coating were investigated. The lab-developed CuMn1.8O4 spinel coating were deposited on Crofer 22 H mesh by electrophoretic deposition and densified by a reduction and re-oxidation process. With these different Crofer 22 H meshes (bare, CuMn2O4-coated, and CuMn1.8O4-coated), anode-supported SOFCs with Sr-doped LaMnO3-based cathode were electrochemically tested at 800 °C for total durations of up to 288 h. Comparing the mitigating effects of the two types of Cu-Mn spinel coatings on Cr-poisoning, it was found that the performance of the denser lab-developed CuMn1.8O4 spinel coating was distinctly better, showing no degradation in the cell electrochemical performance and significantly less Cr deposition near the cathode/electrolyte interface after the test.

Determinantes dos preços de terras no Brasil: uma análise de região de fronteira agrícola e áreas tradicionais

Directory of Open Access Journals (Sweden)

Aline Barrozo Ferro

2013-09-01

Full Text Available O estudo tem como objetivo analisar o impacto de variáveis sobre o preço da terra agrícola entre 2000 e 2010 em três regiões: fronteira agrícola (sul do Maranhão, sul do Piauí, leste do Tocantins e oeste da Bahia, área de transição (exploração relativamente recente, mas representa um importante produtor de soja, como o Centro-Oeste e desenvolvida (áreas tradicionais, como o Sul do País. Foram utilizadas as variáveis preço de soja, produtividade, área cultivada, crédito rural, investimento em transporte, capacidade de armazenamento e preço da terra no período anterior. A partir do modelo econométrico de dados em painel, observou-se que o preço da soja (representando a renda do produtor, teve relação estreita e positiva com o preço da terra. Verificou-se, também, que nas regiões menos ocupadas um aumento da demanda por área pode impactar negativamente em seu preço devido à maior elasticidade da oferta de terras e à possibilidade de conversão de terras brutas e de pastagens em agrícolas. Já na região desenvolvida, a relação é positiva, já que a oferta de terras é praticamente inelástica. O fator especulativo foi bastante representativo na fronteira agrícola, o que evidenciou o forte interesse de investidores no potencial de valorização da terra no período.

Verificação de requisitos de segurança de tratores agrícolas em alguns municípios do estado de São Paulo

Directory of Open Access Journals (Sweden)

Ila Maria Corrêa

Full Text Available Um levantamento de informações foi realizado com o objetivo de avaliar as condições de segurança de tratores agrícolas novos e usados em alguns municípios do estado de São Paulo. Foram avaliados 487 tratores em uso em 270 propriedades agrícolas do estado de São Paulo e 31 tratores novos disponíveis em revendas e em exposição em feiras agrícolas, sendo inspecionados alguns requisitos de segurança relativos a posto de operação, acesso, comandos, proteção de partes móveis, disponibilização de avisos contra riscos de acidentes e requisitos necessários para tráfego em rodovias, previstos em documentos normativos nacionais e/ou internacionais. Verificou-se que os tratores em uso no campo não favorecem a segurança e o conforto do operador, enquanto que os tratores novos mostram tendência de atendimento aos requisitos de segurança e conforto, principalmente aqueles relacionados ao posto de operação e à proteção de partes ativas.

Waste Isolation Pilot Plant Transuranic Waste Baseline inventory report. Volume 1. Revision 1

International Nuclear Information System (INIS)

1995-02-01

This document provides baseline inventories of transuranic wastes for the WIPP facility. Information on waste forms, forecasting of future inventories, and waste stream originators is also provided. A diskette is provided which contains the inventory database

Waste Isolation Pilot Plant Transuranic Waste Baseline inventory report. Volume 1. Revision 1

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-02-01

This document provides baseline inventories of transuranic wastes for the WIPP facility. Information on waste forms, forecasting of future inventories, and waste stream originators is also provided. A diskette is provided which contains the inventory database.

Fungos micorrízicos arbusculares em campos de murundus após a conversão para sistemas agrícolas no cerrado

Directory of Open Access Journals (Sweden)

Paula Camylla Ramos Assis

2014-12-01

Full Text Available Os campos de murundus são fitofisionomias de ocorrência no bioma Cerrado com funções ecológicas importantes para a manutenção da sustentabilidade do solo; e a conversão para sistemas agrícolas pode provocar alterações nos atributos físicos, químicos e biológicos do solo ainda não avaliados, como a redução da biodiversidade de fungos micorrízicos arbusculares. O objetivo deste estudo foi avaliar como a conversão dos campos de murundus em áreas de sistema agrícola altera a comunidade de fungos micorrízicos arbusculares (FMAs. Os tratamentos constituíram-se de três áreas agrícolas submetidas ao mesmo manejo e uso agrícola em uma cronossequência (7, 11 e 14 anos e duas na área referência [campo de murundus, em topo (TM e entre os murundus (EM]. Os esporos de FMAs foram extraídos, contados, e as espécies de FMAs identificadas pelas características morfológicas. O total de FMAs recuperado foi de 27 espécies, sendo nove espécies da família Acaulosporaceae, uma Ambisporaceae, sete Glomeraceae, duas Claroideoglomeraceae e oito Gigasporaceae. Desse total, as espécies Acaulospora scrobiculata, Glomus macrocarpum, e Gigaspora sp. ocorreram em todas as áreas nos dois anos estudados. As espécies Acaulospora mellea, Acaulospora cavernata, Acaulospora colombiana, Glomus diaphanum, Scutellospora reticulata e Scutellospora sp. só foram encontradas nos campos de murundus. A conversão de campos de murundus em área agrícola modificou a ocorrência e composição da comunidade de FMAs; as espécies Acaulospora scrobiculata, Glomus macrocarpum, Claroideoglomus etunicatus e Gigaspora sp ocorreram em todas as áreas e a não ocorrência de algumas espécies nas áreas de cultivo, como as espécies Acaulospora cavernata, Acaulospora colombiana, Rhizophagus diaphanus, Scutellospora reticulata e Scutellospora sp. representa perda de diversidade desses fungos. Portanto, este estudo tratou-se do primeiro relato da ocorrência e da

The arabidopsis thaliana AGRAVITROPIC 1 gene encodes a component of the polar-auxin-transport efflux carrier

Science.gov (United States)

Chen, R.; Hilson, P.; Sedbrook, J.; Rosen, E.; Caspar, T.; Masson, P. H.

1998-01-01

Auxins are plant hormones that mediate many aspects of plant growth and development. In higher plants, auxins are polarly transported from sites of synthesis in the shoot apex to their sites of action in the basal regions of shoots and in roots. Polar auxin transport is an important aspect of auxin functions and is mediated by cellular influx and efflux carriers. Little is known about the molecular identity of its regulatory component, the efflux carrier [Estelle, M. (1996) Current Biol. 6, 1589-1591]. Here we show that mutations in the Arabidopsis thaliana AGRAVITROPIC 1 (AGR1) gene involved in root gravitropism confer increased root-growth sensitivity to auxin and decreased sensitivity to ethylene and an auxin transport inhibitor, and cause retention of exogenously added auxin in root tip cells. We used positional cloning to show that AGR1 encodes a putative transmembrane protein whose amino acid sequence shares homologies with bacterial transporters. When expressed in Saccharomyces cerevisiae, AGR1 promotes an increased efflux of radiolabeled IAA from the cells and confers increased resistance to fluoro-IAA, a toxic IAA-derived compound. AGR1 transcripts were localized to the root distal elongation zone, a region undergoing a curvature response upon gravistimulation. We have identified several AGR1-related genes in Arabidopsis, suggesting a global role of this gene family in the control of auxin-regulated growth and developmental processes.

Polymeric ionic liquid coatings versus commercial solid-phase microextraction coatings for the determination of volatile compounds in cheeses.

Science.gov (United States)

Trujillo-Rodríguez, María J; Yu, Honglian; Cole, William T S; Ho, Tien D; Pino, Verónica; Anderson, Jared L; Afonso, Ana M

2014-04-01

The extraction performance of four polymeric ionic liquid (PIL)-based solid-phase microextraction (SPME) coatings has been studied and compared to that of commercial SPME coatings for the extraction of 16 volatile compounds in cheeses. The analytes include 2 free fatty acids, 2 aldehydes, 2 ketones and 10 phenols and were determined by headspace (HS)-SPME coupled to gas chromatography (GC) with flame-ionization detection (FID). The PIL-based coatings produced by UV co-polymerization were more efficient than PIL-based coatings produced by thermal AIBN polymerization. Partition coefficients of analytes between the sample and the coating (Kfs) were estimated for all PIL-based coatings and the commercial SPME fiber showing the best performance among the commercial fibers tested: carboxen-polydimethylsyloxane (CAR-PDMS). For the PIL-based fibers, the highest K(fs) value (1.96 ± 0.03) was obtained for eugenol. The normalized calibration slope, which takes into account the SPME coating thickness, was also used as a simpler approximate tool to compare the nature of the coating within the determinations, with results entirely comparable to those obtained with estimated K(fs) values. The PIL-based materials obtained by UV co-polymerization containing the 1-vinyl-3-hexylimidazolium chloride IL monomer and 1,12-di(3-vinylimiazolium)dodecane dibromide IL crosslinker exhibited the best performance in the extraction of the select analytes from cheeses. Despite a coating thickness of only 7 µm, this copolymeric sorbent coating was capable of quantitating analytes in HS-SPME in a 30 to 2000 µg L(-1) concentration range, with correlation coefficient (R) values higher than 0.9938, inter-day precision values (as relative standard deviation in %) varying from 6.1 to 20%, and detection limits down to 1.6 µg L(-1). Copyright © 2013 Elsevier B.V. All rights reserved.

Studies on soft centered coated snacks.

Science.gov (United States)

Pavithra, A S; Chetana, Ramakrishna; Babylatha, R; Archana, S N; Bhat, K K

2013-04-01

Roasted groundnut seeds, amaranth and dates pulp formed the center filling which was coated with sugar, breadings, desiccated coconut and roasted Bengalgram flour (BGF) to get 4 coated snacks. Physicochemical characteristics, microbiological profile, sorption behaviour and sensory quality of 4 coated snacks were determined. Centre filling to coating ratio of the products were in the range of 3:2-7:1, the product having BGF coating had the thinnest coating. Center filling had soft texture and the moisture content was 10.2-16.2% coating had lower moisture content (4.4-8.6%) except for Bengal gram coating, which had 11.1% moisture. Sugar coated snack has lowest fat (11.6%) and protein (7.2%) contents. Desiccated coconut coated snack has highest fat (25.4%) and Bengal gram flour coated snack had highest protein content (15.4%). Sorption studies showed that the coated snack had critical moisture content of 11.2-13.5%. The products were moisture sensitive and hence require packaging in films having higher moisture barrier property. In freshly prepared snacks coliforms, yeast and mold were absent. Mesophillic aerobes count did not show significant change during 90 days of storage at 27 °C and 37 °C. Sensory analysis showed that products had a unique texture due to combined effect of fairly hard coating and soft center. Flavour and overall quality of all the products were rated as very good.

Impactos provocados por la sequía agrícola en el cultivo de Plátano (Musa en áreas del municipio Venezuela, Ciego de Ávila, Cuba

Directory of Open Access Journals (Sweden)

Yurisbel Gallardo Ballat

2017-12-01

Full Text Available En la presente investigación se realiza el análisis del impacto provocado por la sequía agrícola en el cultivo del Plátano Vianda (Musa paradisiaca en un período de 13 años en áreas de municipio de Venezuela de la provincia de Ciego de Ávila. Cuba, para el análisis de los períodos de sequía se utilizó el Índice de Sequía Agraria (ISA el cual presenta dentro de su algoritmo matemático como variables determinantes la Evapotranspiración de Referencia, que en este caso se determinó con el método de Penman Monteith FAO-1998, el déficit de humedad, la precipitación efectiva y el rendimiento agrícola. Los resultados obtenidos demuestran que los procesos de sequías agrícolas se manifiestan en todos los ciclos del cultivo, afectando de manera general los rendimientos, la evaluación de fenómeno es de gran utilidad para el manejo sostenible de ecosistemas agrarios en aras de lograr mejores resultados productivos a mediano y corto plazo. El análisis de este fenómeno climatológico desde el punto de vista agrícola, permite trazar estrategias para la aplicación de métodos de conservación del suelo y del recurso hídrico a los agricultores.

Calidad de Andosols en sistemas forestal, agroforestal y agrícola con diferentes manejos en Zacatlán, Puebla

Directory of Open Access Journals (Sweden)

Jonathan Omar Hernández Ordoñez

2017-04-01

Full Text Available Los estudios de suelos en sistemas agroforestales relacionados con bosques mesófilos de montaña han sido poco abordados en nuestro país, especialmente los desarrollados en Andosols, los cuales son susceptibles a los procesos de degradación por el cambio de uso del suelo. El presente estudio se realizó en el municipio de Zacatlán, Puebla con el objetivo de caracterizar la calidad de los Andosols bajo diferentes sistemas de manejo. Los métodos que se emplearon fueron: entrevistas a productores para identificar los sistemas, descripción de perfiles de suelos, análisis de laboratorio y análisis de similaridad de los diferentes manejos. Los resultados indicaron que la zona de estudio está integrada por tres sistemas: bosque mesófilo de Montaña (BMM, agroforestal (asociaciones manzana-maíz-calabaza-arándanos y agrícola, con adición de abonos orgánicos (FO o fertilización inorgánica (FI. En los Andosols con BMM, la estructura biológica domina (agregados migajosos y granulares hasta los 55 cm de profundidad, presentan alto contenido de materia orgánica del suelo (MOS (31%, alta retención de humedad (194.5% y baja densidad aparente (Da (0.49 g cm-3. Con el cambio de uso de suelo (de bosque a agroforestal o agrícola, la estructura biológica se reduce en espesor o desaparece y dominan los bloques sub-angulares, debido a la disminución drástica del contenido de MOS (a 16.3 o a 6.3%, y retención de humedad (de 97 o a 47%. Además, la Da aumentó hasta 1 g cm-3 en el sistema agrícola. Por el contrario, en tierras degradadas, el sistema agroforestal con manejo orgánico ha mejorado la calidad del horizonte superficial en menos de seis años y con la FO o FI algunos sistemas agroforestales aumentaron los contenidos de Ntot y P. Los índices que mejor caracterizaron la calidad de los Andosols bajo diferentes sistemas fueron: estructura del suelo, MOS, Ntot, P y retención de humedad.

Reseña de tesis doctoral: Consolidación de cadenas globales de valor y desarrollo de clusters locales: El caso de la maquinaria agrícola en Argentina

OpenAIRE

Lan, Diana

2015-01-01

El aporte del trabajo de investigación desarrollado por Federico Langard tiene que ver con la industria de maquinaria agrícola argentina y su larga tradición originada en el desarrollo de la agricultura pampeana. Se concentra en el Este de Córdoba y el Centro-Sur de Santa Fe. Esta industria aparece por las necesidades de las formas de producción agrícola, como talleres de reparación de maquinaria importada y luego como productoras que adaptan y fabrican los productos más complejos tecnológica...

Thin coatings for heavy industry: Advanced coatings for pipes and valves

Science.gov (United States)

Vernhes, Luc

Pipes and valves are pressure vessels that regulate the flow of materials (liquids, gases, and slurries) by controlling the passageways. To optimize processes, reduce costs, and comply with government regulations, original equipment manufacturers (OEMs) must maintain their products in state-of-the-art condition. The first valves were invented over 3,000 years ago to supply water to farms and cities. They were made with bronze alloys, providing good corrosion resistance and acceptable tribological performance. The industrial revolution drove manufacturers to develop new and improved tribological materials. In the 20th century, innovative alloys such as Monel copper-nickel and Stellite cobalt-chrome as well as hard chrome plating were introduced to better control tribological properties and maximize in-service life. Since then, new materials have been regularly introduced to extend the range of applications for valves. For example, Teflon fluoropolymers are used in corrosive chemical and petrochemical processes, the nickel-based superalloys Hastelloy and Inconel for petrochemical applications, and creep-resistant chromium-rich F91 steel for supercritical power plants. Recently, the valve industry has embraced the use of hard thermal sprayed coatings for the most demanding applications, and is investing heavily in research to develop the most suitable coatings for specific uses. There is increasing evidence that the optimal solution to erosive, corrosive, and fretting wear problems lies in the design and manufacture of multi-layer, graded, and/or nanostructured coatings and coating systems that combine controlled hardness with high elastic modulus, high toughness, and good adhesion. The overall objectives of this thesis were 1) to report on advances in the development of structurally controlled hard protective coatings with tailored mechanical, elastoplastic, and thermal properties; and 2) to describe enhanced wear-, erosion-, and corrosion-resistance and other

Pentose sugars inhibit metabolism and increase expression of an AgrD-type cyclic pentapeptide in Clostridium thermocellum.

Science.gov (United States)

Verbeke, Tobin J; Giannone, Richard J; Klingeman, Dawn M; Engle, Nancy L; Rydzak, Thomas; Guss, Adam M; Tschaplinski, Timothy J; Brown, Steven D; Hettich, Robert L; Elkins, James G

2017-02-23

Clostridium thermocellum could potentially be used as a microbial biocatalyst to produce renewable fuels directly from lignocellulosic biomass due to its ability to rapidly solubilize plant cell walls. While the organism readily ferments sugars derived from cellulose, pentose sugars from xylan are not metabolized. Here, we show that non-fermentable pentoses inhibit growth and end-product formation during fermentation of cellulose-derived sugars. Metabolomic experiments confirmed that xylose is transported intracellularly and reduced to the dead-end metabolite xylitol. Comparative RNA-seq analysis of xylose-inhibited cultures revealed several up-regulated genes potentially involved in pentose transport and metabolism, which were targeted for disruption. Deletion of the ATP-dependent transporter, CbpD partially alleviated xylose inhibition. A putative xylitol dehydrogenase, encoded by Clo1313_0076, was also deleted resulting in decreased total xylitol production and yield by 41% and 46%, respectively. Finally, xylose-induced inhibition corresponds with the up-regulation and biogenesis of a cyclical AgrD-type, pentapeptide. Medium supplementation with the mature cyclical pentapeptide also inhibits bacterial growth. Together, these findings provide new foundational insights needed for engineering improved pentose utilizing strains of C. thermocellum and reveal the first functional Agr-type cyclic peptide to be produced by a thermophilic member of the Firmicutes.

Comparative effects of aspirin and enteric-coated aspirin on loss of chromium 51-labeled erythrocytes from the gastrointestinal tract

International Nuclear Information System (INIS)

Robbins, D.C.; Schwartz, R.S.; Kutny, K.; Vallejo, G.; Horton, E.S.; Cotter, J.M.

1984-01-01

Sodium chromate Cr 51 was used to label red blood cells of 19 healthy male volunteers, whose stools were collected for four days before and four days during oral administration of either uncoated (N . 9) or enteric-coated (N . 10) aspirin. Each subject received 2.925 gm/day of aspirin, in three equal doses separated by eight-hour intervals, for a total of seven days. During drug use, stools were collected on days 4 through 7. Fecal blood content, estimated by measuring radioactivity in the stools, was significantly higher (P less than 0.001) during use of either type of aspirin than at baseline, but losses measured during use of the coated aspirin (mean, 1.54 ml/day) were significantly lower (P less than 0.001) than those measured during use of the uncoated aspirin (mean, 4.33 ml/day). The two types of aspirin produced equivalent serum concentrations of salicylates. We conclude that enteric-coated aspirin reduces gastrointestinal blood loss

AGR-3/4 Irradiation Test Train Disassembly and Component Metrology First Look Report

Energy Technology Data Exchange (ETDEWEB)

Stempien, John Dennis [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rice, Francine Joyce [Idaho National Lab. (INL), Idaho Falls, ID (United States); Harp, Jason Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Winston, Philip Lon [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2016-09-01

The AGR-3/4 experiment was designed to study fission product transport within graphitic matrix material and nuclear-grade graphite. To this end, this experiment consisted of 12 capsules, each fueled with 4 compacts containing UCO TRISO particles as driver fuel and 20 UCO designed-to-fail (DTF) fuel particles in each compact. The DTF fuel was fabricated with a thin pyrocarbon layer which was intended to fail during irradiation and provide a source of fission products. These fission products could then migrate through the compact and into the surrounding concentric rings of graphitic matrix material and/or nuclear graphite. Through post-irradiation examination (PIE) of the rings (including physical sampling and gamma scanning) fission product concentration profiles within the rings can be determined. These data can be used to elucidate fission product transport parameters (e.g. diffusion coefficients within the test materials) which will be used to inform and refine models of fission product transport. After irradiation in the Advanced Test Reactor (ATR) had been completed in April 2014, the AGR-3/4 experiment was shipped to the Hot Fuel Examination Facility (HFEF) at the Materials and Fuels Complex (MFC) for inspection, disassembly, and metrology. The AGR-3/4 test train was received at MFC in two separate shipments between February and April 2015. Visual examinations of the test train exterior did not indicate dimensional distortion, and only two small discolored areas were observed at the bottom of Capsules 8 and 9. No corresponding discoloration was found on the inside of these capsules, however. Prior to disassembly, the two test train sections were subject to analysis via the Precision Gamma Scanner (PGS), which did not indicate that any gross fuel relocation had occurred. A series of specialized tools (including clamps, cutters, and drills) had been designed and fabricated in order to carry out test train disassembly and recovery of capsule components (graphite

AGR-3/4 Irradiation Test Train Disassembly and Component Metrology First Look Report

Energy Technology Data Exchange (ETDEWEB)

Stempien, John Dennis [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rice, Francine Joyce [Idaho National Lab. (INL), Idaho Falls, ID (United States); Harp, Jason Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Winston, Philip Lon [Idaho National Lab. (INL), Idaho Falls, ID (United States)

2016-03-01

The AGR-3/4 experiment was designed to study fission product transport within graphitic matrix material and nuclear-grade graphite. To this end, this experiment consisted of 12 capsules, each fueled with 4 compacts containing UCO TRISO particles as driver fuel and 20 UCO designed-to-fail (DTF) fuel particles in each compact. The DTF fuel was fabricated with a thin pyrocarbon layer which was intended to fail during irradiation and provide a source of fission products. These fission products could then migrate through the compact and into the surrounding concentric rings of graphitic matrix material and/or nuclear graphite. Through post-irradiation examination (PIE) of the rings (including physical sampling and gamma scanning) fission product concentration profiles within the rings can be determined. These data can be used to elucidate fission product transport parameters (e.g. diffusion coefficients within the test materials) which will be used to inform and refine models of fission product transport. After irradiation in the Advanced Test Reactor (ATR) had been completed in April 2014, the AGR-3/4 experiment was shipped to the Hot Fuel Examination Facility (HFEF) at the Materials and Fuels Complex (MFC) for inspection, disassembly, and metrology. The AGR-3/4 test train was received at MFC in two separate shipments between February and April 2015. Visual examinations of the test train exterior did not indicate dimensional distortion, and only two small discolored areas were observed at the bottom of Capsules 8 and 9. No corresponding discoloration was found on the inside of these capsules, however. Prior to disassembly, the two test train sections were subject to analysis via the Precision Gamma Scanner (PGS), which did not indicate that any gross fuel relocation had occurred. A series of specialized tools (including clamps, cutters, and drills) had been designed and fabricated in order to carry out test train disassembly and recovery of capsule components (graphite

Baseline Projection Data Book: GRI baseline projection of U.S. Energy Supply and Demand to 2010. 1992 Edition. Volume 1 and Volume 2

International Nuclear Information System (INIS)

Holtberg, P.D.; Woods, T.J.; Lihn, M.L.; Koklauner, A.K.

1992-01-01

The 1992 Baseline Projection Data Book provides backup data in tabular form for the 1992 GRI Baseline Projection of U.S. Energy Supply and Demand to 2010. Summary tables and data for the residential, commercial, industrial, electric utility, and transportation sectors are presented in the volume

Requisitos ambientais e acesso a mercados: o setor de defensivos agrícolas Environmental requirements and market access: the pesticide sector

Directory of Open Access Journals (Sweden)

Ricardo K.S. Fermam

2008-12-01

Full Text Available Os requisitos ambientais do comércio internacional são freqüentemente usados pelos países desenvolvidos como barreiras técnicas ao acesso a mercados pelos países em desenvolvimento. Conhecer estes requisitos é especialmente importante para o setor de defensivos agrícolas (pesticidas. Assim, este artigo busca identificar os principais requisitos ambientais relativos aos defensivos agrícolas, mostrando a importância dos mesmos para os comércio exterior dos países em desenvolvimento, especialmente o Brasil.The environmental requirements of the international trade are frequently used for the developed countries as technical barriers to the market access for the developing countries. To know these requirements is especially important for the sector of agricultural defensives (pesticides. Thus, this Article seeks to identify the main environmental requirements regards to the agricultural defensives, showing the importance of the same ones for the foreign trade of the developing countries, especially Brazil.

Efectos del tlcan sobre el empleo de mano de obra en el sector agrícola de México, 1994-2010

Directory of Open Access Journals (Sweden)

Yuliana Lechuga Jardínez

2014-01-01

Full Text Available el Tratado de Libre Comercio de América del Norte se implementó en 1994 para solucionar el desempleo de mano de obra en el campo mexicano, sin embargo, actual - mente las zonas rurales del país enfrentan el mismo pro - blema. Se calcularon las fuentes de crecimiento del em - pleo de mano de obra, de 1994 a 2010, con la finalidad de determinar su impacto sobre el sector agrícola de Méxi - co. Los resultados indican que el cambio en la estructura productiva fue desfavorable para el empleo en general, no obstante, el agrícola creció en diez millones de jornadas debido a un incremento en la superficie cosechada y a un aumento en los requerimientos de mano de obra. En Sinaloa, el cambio en la estructura productiva y una ma - yor mecanización perjudicaron al empleo, a diferencia de lo ocurrido en Estado de México y Chiapas, en donde lo beneficiaron.

Contrato de maquinaria agrícola en el noroeste de la provincia de Buenos Aires

OpenAIRE

Ullua, Adrián

2017-01-01

En el presente trabajo se aborda el contrato de maquinaria agrícola, citando a diversos autores y su encuadre jurídico. Los cambios introducidos en el nuevo Código Civil y Comercial. La tipicidad de este tipo de contratos y las modalidades de cómo se desarrolla en el noroeste de la provincia de Aires. Para este último punto se ha utilizado el método de entrevistas, tanto a contratistas como productores agropecuarios, para tratar de vislumbrar, si se trata de contratos atípicos o subtipos cont...

Coatings for directional eutectics

Science.gov (United States)

Rairden, J. R.; Jackson, M. R.

1976-01-01

Coatings developed to provide oxidation protection for the directionally-solidified eutectic alloy NiTaC-B (4.4 weight percent Cr) were evaluated. Of seven Co-, Fe- and Ni-base coatings that were initially investigated, best resistance to cyclic oxidation was demonstrated by duplex coatings fabricated by depositing a layer of NiCrAl(Y) by vacuum evaporation from an electron beam source followed by deposition of an Al overlayer using the pack cementation process. It was found that addition of carbon to the coating alloy substantially eliminated the problem of fiber denudation in TaC-type eutectic alloys. Burner rig cycled NiTaC-B samples coated with Ni-20Cr-5Al-0.1C-0.1Y+Al and rupture-tested at 1100 deg C performed as well as or better than uncoated, vacuum cycled and air-tested NiTaC-13; however, a slight degradation with respect to uncoated material was noted in air-stress rupture tests at 870 deg C for both cycled and uncycled samples.

Superhydrophobic silica coating by dip coating method

International Nuclear Information System (INIS)

Mahadik, Satish A.; Parale, Vinayak; Vhatkara, Rajiv S.; Mahadik, Dinesh B.; Kavale, Mahendra S.; Wagh, Pratap B.; Gupta, Satish; Gurav, Jyoti

2013-01-01

Herein, we report a simple and low cost method for the fabrication of superhydrophobic coating surface on quartz substrates via sol-gel dip coating method at room temperature. Desired surface chemistry and texture growth for superhydrophobicity developed under double step sol–gel process at room temperature. The resultant superhydrophobic surfaces were characterized by Field-emission scanning electron microscopy (FE-SEM), Atomic force microscopy (AFM), water contact angle (WCA) measurement, differential thermal gravimetric analysis-differential thermal analysis (TGA-DTA) calorimetry and optical spectrometer. Coating shows the ultra high water contact angle about 168 ± 2° and water sliding angle 3 ± 1° and superoleophilic with petroleum oils. This approach allows a simple strategy for the fabrication process of superhydrophilic–superhydrophobic on same surfaces with high thermal stability of superhydrophobicity up to 560 °C. Thus, durability, special wettability and thermal stability of superhydrophobicity expand their application fields.

Remote inspection manipulators for AGR II: Babcock Power's interstitial manipulator

International Nuclear Information System (INIS)

Whyley, S.R.

1985-01-01

The interstitial manipulator has been designed and built by Babcock Power for the remote visual inspection of AGR II reactors at Heysham and Torness. Its five drives are operated from a console local to the manipulator on the pile cap, or from a similar console located remotely. The need to operate from an interstitial ISI standpipe has restricted the size of the components entering the reactor, and this has consequently provided the major design constraint. A detailed structural assessment of the manipulator was carried out to demonstrate the ability to operate with payloads in excess of the largest camera weight of 13.6 kg. The manipulator finite element model was also used to determine static deflections, and, as a consequence, has provided data from which the control system is able to predict accurately the camera's position. Other computer aided design techniques have enabled the step by step sequences of manipulator deployment, in the restricted space available, to be successfully demonstrated. (author)

Lucienville's Agriculture Corp. Ltda. Cooperativa Agrícola Lucienville Ltda.

Directory of Open Access Journals (Sweden)

Patricia Boari

2008-01-01

Full Text Available Since the evolution of agriculture corporativism and through its memoirs and balance books the present study analyzes the development of Lucienville's Agriculture Corp. Ltda. during the historic peronism. On this stage the institution got a particular incidence on diverse economic activities of national agro (seed accumulation, its industrialization and commercialization, at the same time it strengthened its role as center of social services to the associates.A partir de la evolución del cooperativismo agrario argentino y a través de sus memorias y balances el presente estudio analiza el desenvolvimiento de la Cooperativa Agrícola Lucienville Ltda. durante el peronismo histórico. En esta etapa la institución adquiere particular incidencia en las diversas actividades económicas del agro regional (acopio de semillas, su industrialización y comercialización, al tiempo que refuerza su rol como centro de servicios sociales para los asociados.

Compostagem de lodo de esgoto para uso agrícola

Directory of Open Access Journals (Sweden)

Mário Viana Paredes Filho

2011-12-01

Full Text Available Este trabalho de revisão de literatura tem o objetivo de demonstrar o potencial existente no lodo de esgoto proveniente das estações de tratamento de esgotos, para que o mesmo seja reaproveitado e utilizado como matéria orgânica fornecedora de nutrientes para o solo. O lodo de esgoto deve ser tratado antes da sua disposição final através de tratamentos biológicos que vão reduzir a carga orgânica e promover a estabilização e higienização do composto. A compostagem apresenta-se como uma técnica viável e relativamente de baixo custo, que atende aos padrões físicos, químicos e microbiológicos exigidos pela legislação pertinente. A reciclagem agrícola do lodo de esgoto torna-se uma alternativa segura para a disposição final deste resíduo.

Nanoparticle/Polymer Nanocomposite Bond Coat or Coating

Science.gov (United States)

Miller, Sandi G.

2011-01-01

This innovation addresses the problem of coatings (meant to reduce gas permeation) applied to polymer matrix composites spalling off in service due to incompatibility with the polymer matrix. A bond coat/coating has been created that uses chemically functionalized nanoparticles (either clay or graphene) to create a barrier film that bonds well to the matrix resin, and provides an outstanding barrier to gas permeation. There is interest in applying clay nanoparticles as a coating/bond coat to a polymer matrix composite. Often, nanoclays are chemically functionalized with an organic compound intended to facilitate dispersion of the clay in a matrix. That organic modifier generally degrades at the processing temperature of many high-temperature polymers, rendering the clay useless as a nano-additive to high-temperature polymers. However, this innovation includes the use of organic compounds compatible with hightemperature polymer matrix, and is suitable for nanoclay functionalization, the preparation of that clay into a coating/bondcoat for high-temperature polymers, the use of the clay as a coating for composites that do not have a hightemperature requirement, and a comparable approach to the preparation of graphene coatings/bond coats for polymer matrix composites.

MC3T3-E1 cell response of amorphous phase/TiO{sub 2} nanocrystal composite coating prepared by microarc oxidation on titanium

Energy Technology Data Exchange (ETDEWEB)

Zhou, Rui [Department of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Wei, Daqing, E-mail: daqingwei@hit.edu.cn [Department of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Yang, Haoyue; Feng, Wei [Department of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Cheng, Su [Department of Mechanical Engineering, School of Architecture and Civil Engineering, Harbin University of Science and Technology, Harbin 150001 (China); Li, Baoqiang; Wang, Yaming; Jia, Dechang; Zhou, Yu [Department of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China)

2014-06-01

Bioactive amorphous phase/TiO{sub 2} nanocrystal (APTN) composite coatings were fabricated by microarc oxidation (MAO) on Ti. The APTN coatings are composed of much amorphous phase with Si, Na, Ca, Ti and O elements and a few TiO{sub 2} nanocrystals. With increasing applied voltage, the micropore density of the APTN coating decreases and the micropore size of the APTN coating increases. The results indicate that less MC3T3-E1 cells attach on the APTN coatings as compared to Ti. However, the APTN coatings greatly enhance the cell proliferation ability and the activity of alkaline phosphatase. The amorphous phase and the concentrations of the released Ca and Si from the APTN coatings during cell culture have significant effects on the cell response. - Highlights: • Amorphous phase/TiO2 nanocrystal (APTN) composite coatings were fabricated. • The MC3T3-E1 cell response of the APTN coatings was evaluated. • The APTN coatings greatly enhanced the cell proliferation ability.

Plasma sprayed thermoregulating coatings

International Nuclear Information System (INIS)

Kudinov, V.V.; Puzanov, A.A.; Zambrzhitskij, A.P.; Soboleva, V.V.

1979-01-01

Shown is the possibility of plasma spraying application for thermoregulating coating formation. Given are test results of service properties of BeO, Al 2 O 2 plasma coatings on the substrates of the MA2-1 magnesium alloy. Described is a device for studying durability of coating optical parameters under ultraviolet irradiation in deep vacuum. Dynamics of absorption coefficient, growth caused by an increase in absorption centers amount under such irradiation is investigated

Plasma processed coating of laser fusion targets

International Nuclear Information System (INIS)

Johnson, W.L.; Letts, S.A.; Myers, D.W.; Crane, J.K.; Illige, J.D.; Hatcher, C.W.

1979-01-01

Coatings for laser fusion targets have been deposited in an inductively coupled discharge device by plasma polymerization. Two feed gases were used: perfluoro-2-butene, which produced a fluorocarbon coating (CF 1 3 ) with a density of 1.8 g/cc, and trans-2-butene which produced a hydrocarbon coating (CH 1 3 ) with a density of 1.0 g/cc. Uniform pin-hole free films have been deposited to a thickness of up to 30 μm of fluorocarbon and up to 110 μm of hydrocarbon. The effect of process variables on surface smoothness has been investigated. The basic defect in the coating has been found to result from shadowing by a small surface irregularity in an anisotropic coating flux