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Sample records for air infiltration rates

  1. Indoor air quality/air infiltration in selected low-energy houses

    International Nuclear Information System (INIS)

    Shohl Wagner, B.; Phillips, T.J.

    1984-01-01

    Indoor air quality and air infiltration were measured in 16 low-energy California houses. Eleven has gas stoves; all had average infiltration rates of 0.5 h -1 of less, recent construction dates, low natural ventilation, and no mechanical ventilation. HCHO levels in 12 houses and radon-222 and NO 2 levels in all houses were measured using passive monitors. Blower door measurements and local weather data were used to calculate average infiltration rates during the monitoring period. Correlation of pollutant concentrations with infiltration rates and building characteristics indicate that new houses with average heating season infiltration rates less than 0.5 h -1 do not necessarily experience poor indoor air quality, HCHO and radon-222 levels in new houses exceeded the lowest currently proposed standards or guidelines, and much higher levels probably exist elsewhere. Therefore, some strategy for identifying 'problem' houses is needed. We recommend an approach for future research in this area. (Author)

  2. Water vapor mass balance method for determining air infiltration rates in houses

    Science.gov (United States)

    David R. DeWalle; Gordon M. Heisler

    1980-01-01

    A water vapor mass balance technique that includes the use of common humidity-control equipment can be used to determine average air infiltration rates in buildings. Only measurements of the humidity inside and outside the home, the mass of vapor exchanged by a humidifier/dehumidifier, and the volume of interior air space are needed. This method gives results that...

  3. Water infiltration in an aquifer recharge basin affected by temperature and air entrapment

    Directory of Open Access Journals (Sweden)

    Loizeau Sébastien

    2017-09-01

    Full Text Available Artificial basins are used to recharge groundwater and protect water pumping fields. In these basins, infiltration rates are monitored to detect any decrease in water infiltration in relation with clogging. However, miss-estimations of infiltration rate may result from neglecting the effects of water temperature change and air-entrapment. This study aims to investigate the effect of temperature and air entrapment on water infiltration at the basin scale by conducting successive infiltration cycles in an experimental basin of 11869 m2 in a pumping field at Crepieux-Charmy (Lyon, France. A first experiment, conducted in summer 2011, showed a strong increase in infiltration rate; which was linked to a potential increase in ground water temperature or a potential dissolution of air entrapped at the beginning of the infiltration. A second experiment was conducted in summer, to inject cold water instead of warm water, and also revealed an increase in infiltration rate. This increase was linked to air dissolution in the soil. A final experiment was conducted in spring with no temperature contrast and no entrapped air (soil initially water-saturated, revealing a constant infiltration rate. Modeling and analysis of experiments revealed that air entrapment and cold water temperature in the soil could substantially reduce infiltration rate over the first infiltration cycles, with respective effects of similar magnitude. Clearly, both water temperature change and air entrapment must be considered for an accurate assessment of the infiltration rate in basins.

  4. Energy use, air infiltration, and indoor air quality in well-insulated residences

    International Nuclear Information System (INIS)

    Koontz, M.D.; Nagda, N.L.

    1989-01-01

    This paper reports two unoccupied bilevel houses of identical design and construction studied to determine the relationships among air exchange, energy consumption, and indoor air quality. The experimental house was retrofitted to increase building tightness and was equipped with an air-to-air heat exchanger; the control house was kept in its initial state of construction. Infiltration, energy, indoor air quality, and environmental parameters were monitored in both houses before and after the retrofit. It was found that the retrofit decreased air infiltration rates by nearly 25 percent, heating energy savings of 12 to 20 percent were achieved through the retrofit, and among the pollutants monitored, only radon and radon progeny increased in proportion to the reduced infiltration. Similarly, when the heat exchanger was operated, radon and radon progeny were the only pollutants reduced in proportion to the added air exchange

  5. Water infiltration in an aquifer recharge basin affected by temperature and air entrapment

    OpenAIRE

    Loizeau Sébastien; Rossier Yvan; Gaudet Jean-Paul; Refloch Aurore; Besnard Katia; Angulo-Jaramillo Rafael; Lassabatere Laurent

    2017-01-01

    Artificial basins are used to recharge groundwater and protect water pumping fields. In these basins, infiltration rates are monitored to detect any decrease in water infiltration in relation with clogging. However, miss-estimations of infiltration rate may result from neglecting the effects of water temperature change and air-entrapment. This study aims to investigate the effect of temperature and air entrapment on water infiltration at the basin scale by conducting successive infiltration c...

  6. Infiltration Variability in Agricultural Soil Aggregates Caused by Air Slaking

    Science.gov (United States)

    Korenkova, L.; Urik, M.

    2018-04-01

    This article reports on variation in infiltration rates of soil aggregates as a result of phenomenon known as air slaking. Air slaking is caused by the compression and subsequent escape of air captured inside soil aggregates during water saturation. Although it has been generally assumed that it occurs mostly when dry aggregates are rapidly wetted, the measurements used for this paper have proved that it takes place even if the wetting is gradual, not just immediate. It is a phenomenon that contributes to an infiltration variability of soils. In measuring the course of water flow through the soil, several small aggregates of five agricultural soils were exposed to distilled water at zero tension in order to characterize their hydraulic properties. Infiltration curves obtained for these aggregates demonstrate the effect of entrapped air on the increase and decrease of infiltration rates. The measurements were performed under various moisture conditions of the A-horizon aggregates using a simple device.

  7. Effects of climate change on residential infiltration and air pollution exposure.

    Science.gov (United States)

    Ilacqua, Vito; Dawson, John; Breen, Michael; Singer, Sarany; Berg, Ashley

    2017-01-01

    Air exchange through infiltration is driven partly by indoor/outdoor temperature differences, and as climate change increases ambient temperatures, such differences could vary considerably even with small ambient temperature increments, altering patterns of exposures to both indoor and outdoor pollutants. We calculated changes in air fluxes through infiltration for prototypical detached homes in nine metropolitan areas in the United States (Atlanta, Boston, Chicago, Houston, Los Angeles, Minneapolis, New York, Phoenix, and Seattle) from 1970-2000 to 2040-2070. The Lawrence Berkeley National Laboratory model of infiltration was used in combination with climate data from eight regionally downscaled climate models from the North American Regional Climate Change Assessment Program. Averaged over all study locations, seasons, and climate models, air exchange through infiltration would decrease by ~5%. Localized increased infiltration is expected during the summer months, up to 20-30%. Seasonal and daily variability in infiltration are also expected to increase, particularly during the summer months. Diminished infiltration in future climate scenarios may be expected to increase exposure to indoor sources of air pollution, unless these ventilation reductions are otherwise compensated. Exposure to ambient air pollution, conversely, could be mitigated by lower infiltration, although peak exposure increases during summer months should be considered, as well as other mechanisms.

  8. Investigation of infiltration and indoor air quality

    International Nuclear Information System (INIS)

    1990-03-01

    A multitask study was performed in the State of New York to provide information for guiding home energy conservation programs while maintaining acceptable indoor air quality. During the study, the statistical distribution of radon concentrations inside 2,400 homes was determined. The relationships among radon levels, house characteristics, and sources were also investigated. The direct impact that two specific air infiltration reduction measures--caulking and weatherstripping of windows and doors, and installation of storm windows and storm doors--have on house air leakage was investigated in 60 homes. The effect of house age on the impact of weatherization was also evaluated. Indoor and outdoor measurements of NO 2 , CO, SO 2 , and respirable suspended particulates (RSP) were made for 400 homes to determine the effect of combustion sources on indoor air quality and to characterize the statistical distribution of the concentrations. Finally, the combustion source data were combined with the information on air infiltration reduction measures to estimate the potential impact of these measures on indoor air quality

  9. Characterizing Heterogeneity in Infiltration Rates During Managed Aquifer Recharge.

    Science.gov (United States)

    Mawer, Chloe; Parsekian, Andrew; Pidlisecky, Adam; Knight, Rosemary

    2016-11-01

    Infiltration rate is the key parameter that describes how water moves from the surface into a groundwater aquifer during managed aquifer recharge (MAR). Characterization of infiltration rate heterogeneity in space and time is valuable information for MAR system operation. In this study, we utilized fiber optic distributed temperature sensing (FO-DTS) observations and the phase shift of the diurnal temperature signal between two vertically co-located fiber optic cables to characterize infiltration rate spatially and temporally in a MAR basin. The FO-DTS measurements revealed spatial heterogeneity of infiltration rate: approximately 78% of the recharge water infiltrated through 50% of the pond bottom on average. We also introduced a metric for quantifying how the infiltration rate in a recharge pond changes over time, which enables FO-DTS to be used as a method for monitoring MAR and informing maintenance decisions. By monitoring this metric, we found high-spatial variability in how rapidly infiltration rate changed during the test period. We attributed this variability to biological pore clogging and found a relationship between high initial infiltration rate and the most rapid pore clogging. We found a strong relationship (R 2  = 0.8) between observed maximum infiltration rates and electrical resistivity measurements from electrical resistivity tomography data taken in the same basin when dry. This result shows that the combined acquisition of DTS and ERT data can improve the design and operation of a MAR pond significantly by providing the critical information needed about spatial variability in parameters controlling infiltration rates. © 2016, National Ground Water Association.

  10. A Non-linear Stochastic Model for an Office Building with Air Infiltration

    DEFF Research Database (Denmark)

    Thavlov, Anders; Madsen, Henrik

    2015-01-01

    This paper presents a non-linear heat dynamic model for a multi-room office building with air infiltration. Several linear and non-linear models, with and without air infiltration, are investigated and compared. The models are formulated using stochastic differential equations and the model...

  11. Linking denitrification and infiltration rates during managed groundwater recharge.

    Science.gov (United States)

    Schmidt, Calla M; Fisher, Andrew T; Racz, Andrew J; Lockwood, Brian S; Huertos, Marc Los

    2011-11-15

    We quantify relations between rates of in situ denitrification and saturated infiltration through shallow, sandy soils during managed groundwater recharge. We used thermal methods to determine time series of point-specific flow rates, and chemical and isotopic methods to assess denitrification progress. Zero order denitrification rates between 3 and 300 μmol L(-1) d(-1) were measured during infiltration. Denitrification was not detected at times and locations where the infiltration rate exceeded a threshold of 0.7 ± 0.2 m d(-1). Pore water profiles of oxygen and nitrate concentration indicated a deepening of the redoxocline at high flow rates, which reduced the thickness of the zone favorable for denitrification. Denitrification rates were positively correlated with infiltration rates below the infiltration threshold, suggesting that for a given set of sediment characteristics, there is an optimal infiltration rate for achieving maximum nitrate load reduction and improvements to water supply during managed groundwater recharge. The extent to which results from this study may be extended to other managed and natural hydrologic settings remains to be determined, but the approach taken in this study should be broadly applicable, and provides a quantitative link between shallow hydrologic and biogeochemical processes.

  12. Indoor air quality and infiltration in multifamily naval housing

    International Nuclear Information System (INIS)

    Parker, G.B.; Wilfert, G.L.; Dennis, G.W.

    1984-11-01

    Measurements of indoor air quality and air infiltration were taken in three units of a multifamily housing complex at the Naval Submarine base in Bangor, Washington, over 5 consecutive days during the heating season of 1983. Three dwelling units of identical size constructed in 1978 were monitored, each in a separate two-story four-unit complex. One unit was a downstairs unit and the other two units were upstairs units. Two of the units were occupied by smokers (one downstairs and one upstairs). None of the units had combustion appliances. Pollutants monitored indoors included radon, formaldehyde, carbon monoxide, particulate matter, and nitrogen dioxide. Indoor and outdoor temperature and windspeed were also recorded. Outdoor formaldehyde and nitrogen dioxide were also measured. Air exchange was measured about three times during each 24-h period, using a perfluorocarbon tracer with automatic tracer sampling. The daily average air exchange rate ranged from 0.22 to 0.91 air changes per hour (ACH). Pollutant concentrations were generally low except for particulate matter in the units with smokers, which were two to four times higher than in the unit with nonsmokers. Levels of carbon monoxide were also slightly elevated in one of the units with a smoker compared to the unit with nonsmokers. 5 references, 4 figures, 4 tables

  13. Probabilistic estimation of residential air exchange rates for population-based human exposure modeling

    Science.gov (United States)

    Residential air exchange rates (AERs) are a key determinant in the infiltration of ambient air pollution indoors. Population-based human exposure models using probabilistic approaches to estimate personal exposure to air pollutants have relied on input distributions from AER meas...

  14. Effect of Irrigation Water Type on Infiltration Rates of Sandy Soil

    International Nuclear Information System (INIS)

    Al-Omran, A.M.; Al-Matrood, S.M.; Choudhary, M.I.

    2004-01-01

    A laboratory experiment was conducted to test the effect of three water types (tap water, well water and sewage water) on the infiltration rate of three soils varying in texture (sand. loamy sand and sandy loam). A stationary rainfall simulator dispensing water at a rate of 45 mm h-1, connected to the different sources of water, was used to measure the infiltration rates. A total of 5 runs were carried out using each water quality. The volume of runoff against the time was recorded at each 5 minute interval. The infiltration rate was calculated as the difference between the water applied and the excesses water measured as surface runoff. Infiltration rate at first run were rapid in all the three soils and then progressively declined as the number of runs increased. The same trend was observed for each water quality tested. The reduction in infiltration rate with increasing number of runs for prewetted surface than for the initial dry surface was attributed to break down and settling of fine particles that took place earlier during prewetting. The infiltration curves for all the three soils when irrigared with different qualities of water was not distinguishable. The relationship between infiltration rate as function of time for the treatments applied were tested using Kostiakov equation I=bt-n. The infiltration data gave a coefficient of determination R2 >0.90 for all the treatments. The infiltration parameters B, and n varied strongly with respect to soil texture. Values of B decreased with changing soil textures, being highest for the sandy soil, and lowest for the sandy loamy soil, whereas n values showed the opposite trend. It was concluded that effect of soil texture on the infiltration rate was very pronounced while water qualities showed a little effect. (author)

  15. Preliminary Investigation on the Behavior of Pore Air Pressure During Rainfall Infiltration

    Science.gov (United States)

    Ashraf Mohamad Ismail, Mohd; Min, Ng Soon; Hasliza Hamzah, Nur; Hazreek Zainal Abidin, Mohd; Madun, Aziman; Tajudin, Saiful Azhar Ahmad

    2018-04-01

    This paper focused on the preliminary investigation of pore air pressure behaviour during rainfall infiltration in order to substantiate the mechanism of rainfall induced slope failure. The actual behaviour or pore air pressure during infiltration is yet to be clearly understood as it is regularly assumed as atmospheric. Numerical modelling of one dimensional (1D) soil column was utilized in this study to provide a preliminary insight of this highlighted uncertainty. Parametric study was performed by using rainfall intensities of 1.85 x 10-3m/s and 1.16 x 10-4m/s applied on glass beads to simulate intense and modest rainfall conditions. Analysis results show that the high rainfall intensity causes more development of pore air pressure compared to low rainfall intensity. This is because at high rainfall intensity, the rainwater cannot replace the pore air smoothly thus confining the pore air. Therefore, the effect of pore air pressure has to be taken into consideration particularly during heavy rainfall.

  16. Characterization of infiltration rates from landfills: supporting groundwater modeling efforts.

    Science.gov (United States)

    Moo-Young, Horace; Johnson, Barnes; Johnson, Ann; Carson, David; Lew, Christine; Liu, Salley; Hancocks, Katherine

    2004-01-01

    The purpose of this paper is to review the literature to characterize infiltration rates from landfill liners to support groundwater modeling efforts. The focus of this investigation was on collecting studies that describe the performance of liners 'as installed' or 'as operated'. This document reviews the state of the science and practice on the infiltration rate through compacted clay liner (CCL) for 149 sites and geosynthetic clay liner (GCL) for 1 site. In addition, it reviews the leakage rate through geomembrane (GM) liners and composite liners for 259 sites. For compacted clay liners (CCL), there was limited information on infiltration rates (i.e., only 9 sites reported infiltration rates.), thus, it was difficult to develop a national distribution. The field hydraulic conductivities for natural clay liners range from 1 x 10(-9) cm s(-1) to 1 x 10(-4) cm s(-1), with an average of 6.5 x 10(-8) cm s(-1). There was limited information on geosynthetic clay liner. For composite lined and geomembrane systems, the leak detection system flow rates were utilized. The average monthly flow rate for composite liners ranged from 0-32 lphd for geomembrane and GCL systems to 0 to 1410 lphd for geomembrane and CCL systems. The increased infiltration for the geomembrane and CCL system may be attributed to consolidation water from the clay.

  17. Relationship between soil erodibility and modeled infiltration rate in different soils

    Science.gov (United States)

    Wang, Guoqiang; Fang, Qingqing; Wu, Binbin; Yang, Huicai; Xu, Zongxue

    2015-09-01

    The relationship between soil erodibility, which is hard to measure, and modeled infiltration rate were rarely researched. Here, the soil erodibility factors (K and Ke in the USLE, Ki and K1 in the WEPP) were calculated and the infiltration rates were modeled based on the designed laboratory simulation experiments and proposed infiltration model, in order to build their relationship. The impacts of compost amendment on the soil erosion characteristics and relationship were also studied. Two contrasting agricultural soils (bare and cultivated fluvo-aquic soils) were used, and different poultry compost contents (control, low and high) were applied to both soils. The results indicated that the runoff rate, sediment yield rate and soil erodibility of the bare soil treatments were generally higher than those of the corresponding cultivated soil treatments. The application of composts generally decreased sediment yield and soil erodibility but did not always decrease runoff. The comparison of measured and modeled infiltration rates indicated that the model represented the infiltration processes well with an N-S coefficient of 0.84 for overall treatments. Significant negative logarithmic correlations have been found between final infiltration rate (FIR) and the four soil erodibility factors, and the relationship between USLE-K and FIR demonstrated the best correlation. The application of poultry composts would not influence the logarithmic relationship between FIR and soil erodibility. Our study provided a useful tool to estimate soil erodibility.

  18. Estimating Infiltration Rates for a Loessal Silt Loam Using Soil Properties

    Science.gov (United States)

    M. Dean Knighton

    1978-01-01

    Soil properties were related to infiltration rates as measured by single-ringsteady-head infiltometers. The properties showing strong simple correlations were identified. Regression models were developed to estimate infiltration rate from several soil properties. The best model gave fair agreement to measured rates at another location.

  19. Effect of Fruits Waste in Biopore Infiltration Hole Toward The Effectiveness of Water Infiltration Rate on Baraya Campus Land of Hasanuddin University

    Science.gov (United States)

    Santosa, Slamet

    2018-03-01

    The infiltration of water into the soil decreases due to the transfer of soill function or the lack of soil biopores. This study aims to determine the effectiveness of the use of fruits waste toward the water infiltration rate. Observation of the water level decrease is done every 5 minutes interval. Observation of biopore water infiltration rate was done after fruits waste decomposed for 15 and 30 days. Result of standard water infiltration rate at the first of 5 minutes is 2.18 mm/min, then decreases at interval of 5 minutes on next time as the soil begins to saturate the water. Baraya campus soil observed in soil depths of 100cm has a dusty texture character, grayish brown color and clumping structure. Soil character indicates low porosity. While biopore water infiltration rate at the first of 5 minute interval is 6.61and 6.95 mm/min on banana waste; 5.55 and 6.61mm/min on papaya waste and 4.26 and 5.39 mm/min on mango waste. The effectiveness of water infiltration rate is 44.45% and 41.93% on banana; 44.61% and 30.09% on papaya and 15.79% and 28.36% on mango. Study concluded that banana waste causes the water infiltration rate most effective in biopore infiltration hole.

  20. Analysis of Factors that Influence Infiltration Rates using the HELP Model

    International Nuclear Information System (INIS)

    Dyer, J.; Shipmon, J.

    2017-01-01

    The Hydrologic Evaluation of Landfill Performance (HELP) model is used by Savannah River National Laboratory (SRNL) in conjunction with PORFLOW groundwater flow simulation software to make longterm predictions of the fate and transport of radionuclides in the environment at radiological waste sites. The work summarized in this report supports preparation of the planned 2018 Performance Assessment for the E-Area Low-Level Waste Facility (LLWF) at the Savannah River Site (SRS). More specifically, this project focused on conducting a sensitivity analysis of infiltration (i.e., the rate at which water travels vertically in soil) through the proposed E-Area LLWF closure cap. A sensitivity analysis was completed using HELP v3.95D to identify the cap design and material property parameters that most impact infiltration rates through the proposed closure cap for a 10,000-year simulation period. The results of the sensitivity analysis indicate that saturated hydraulic conductivity (Ksat) for select cap layers, precipitation rate, surface vegetation type, and geomembrane layer defect density are dominant factors limiting infiltration rate. Interestingly, calculated infiltration rates were substantially influenced by changes in the saturated hydraulic conductivity of the Upper Foundation and Lateral Drainage layers. For example, an order-of-magnitude decrease in Ksat for the Upper Foundation layer lowered the maximum infiltration rate from a base-case 11 inches per year to only two inches per year. Conversely, an order-of-magnitude increase in Ksat led to an increase in infiltration rate from 11 to 15 inches per year. This work and its results provide a framework for quantifying uncertainty in the radionuclide transport and dose models for the planned 2018 E-Area Performance Assessment. Future work will focus on the development of a nonlinear regression model for infiltration rate using Minitab 17® to facilitate execution of probabilistic simulations in the GoldSim® overall

  1. Analysis of Factors that Influence Infiltration Rates using the HELP Model

    Energy Technology Data Exchange (ETDEWEB)

    Dyer, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Shipmon, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-09-28

    The Hydrologic Evaluation of Landfill Performance (HELP) model is used by Savannah River National Laboratory (SRNL) in conjunction with PORFLOW groundwater flow simulation software to make longterm predictions of the fate and transport of radionuclides in the environment at radiological waste sites. The work summarized in this report supports preparation of the planned 2018 Performance Assessment for the E-Area Low-Level Waste Facility (LLWF) at the Savannah River Site (SRS). More specifically, this project focused on conducting a sensitivity analysis of infiltration (i.e., the rate at which water travels vertically in soil) through the proposed E-Area LLWF closure cap. A sensitivity analysis was completed using HELP v3.95D to identify the cap design and material property parameters that most impact infiltration rates through the proposed closure cap for a 10,000-year simulation period. The results of the sensitivity analysis indicate that saturated hydraulic conductivity (Ksat) for select cap layers, precipitation rate, surface vegetation type, and geomembrane layer defect density are dominant factors limiting infiltration rate. Interestingly, calculated infiltration rates were substantially influenced by changes in the saturated hydraulic conductivity of the Upper Foundation and Lateral Drainage layers. For example, an order-of-magnitude decrease in Ksat for the Upper Foundation layer lowered the maximum infiltration rate from a base-case 11 inches per year to only two inches per year. Conversely, an order-of-magnitude increase in Ksat led to an increase in infiltration rate from 11 to 15 inches per year. This work and its results provide a framework for quantifying uncertainty in the radionuclide transport and dose models for the planned 2018 E-Area Performance Assessment. Future work will focus on the development of a nonlinear regression model for infiltration rate using Minitab 17® to facilitate execution of probabilistic simulations in the GoldSim® overall

  2. Probabilistic estimation of residential air exchange rates for ...

    Science.gov (United States)

    Residential air exchange rates (AERs) are a key determinant in the infiltration of ambient air pollution indoors. Population-based human exposure models using probabilistic approaches to estimate personal exposure to air pollutants have relied on input distributions from AER measurements. An algorithm for probabilistically estimating AER was developed based on the Lawrence Berkley National Laboratory Infiltration model utilizing housing characteristics and meteorological data with adjustment for window opening behavior. The algorithm was evaluated by comparing modeled and measured AERs in four US cities (Los Angeles, CA; Detroit, MI; Elizabeth, NJ; and Houston, TX) inputting study-specific data. The impact on the modeled AER of using publically available housing data representative of the region for each city was also assessed. Finally, modeled AER based on region-specific inputs was compared with those estimated using literature-based distributions. While modeled AERs were similar in magnitude to the measured AER they were consistently lower for all cities except Houston. AERs estimated using region-specific inputs were lower than those using study-specific inputs due to differences in window opening probabilities. The algorithm produced more spatially and temporally variable AERs compared with literature-based distributions reflecting within- and between-city differences, helping reduce error in estimates of air pollutant exposure. Published in the Journal of

  3. Analysis of physical properties controlling steady-state infiltration rates on tropical savannah soils

    International Nuclear Information System (INIS)

    Mbagwu, J.S.C.

    1993-10-01

    A knowledge of physical properties influencing the steady-state infiltration rates (ic) of soils is needed for the hydrologic modelling of the infiltration process. In this study evidence is provided to show that effective porosity (Pe) (i.e. the proportion of macro pore spaces with equivalent radius of > 15 μm) and dry bulk density are the most important soil physical properties controlling the steady-state infiltration rates on a tropical savannah with varying land use histories. At a macro porosity value of ≤ 5.0% the steady-state infiltration rate is zero. Total porosity and the proportion of water-retaining pores explained only a small fraction of the variation in this property. Steady-state infiltration rates can also be estimated from either the saturated hydraulic conductivity (Ks) by the equation, i c = 31.1 + 1.06 (Ks), (R 2 = 0.8104, p ≤ 0.001) or the soil water transmissivity (A) by the equation, i c = 30.0 + 29.9(A), (R 2 = 0.8228, ρ ≤ 0.001). The Philip two-parameter model under predicted steady-state infiltration rates generally. Considering the ease of determination and reliability it is suggested that effective porosity be used to estimate the steady-state infiltration rates of these other soils with similar characteristics. The model is, i c 388.7(Pe) - 10.8(R 2 = 0.7265, p ≤ 0.001) where i c is in (cm/hr) and Pe in (cm 3 /cm 3 ). (author). 20 refs, 3 figs, 4 tabs

  4. Vadose Zone Infiltration Rates from Sr isotope Measurements

    Science.gov (United States)

    Maher, K.; Maher, K.; DePaolo, D. J.; DePaolo, D. J.; Conrad, M.

    2001-12-01

    Predicting infiltration rates and recharge through the vadose zone in arid regions is difficult and hence developing methods for the measurement of infiltration rates is important. We have been investigating the use of Sr isotope measurements for determining infiltration at the 200 Area plateau on the Hanford reservation in central Washington. In this context, infiltration affects the transport of contaminants to the water table as well as recharge of the groundwater system. Using Sr isotopes for this purpose requires drill core and water samples from the vadose zone, although leaches of the cores can substitute for water samples. Complementary information, including some constraints on regional recharge, can also be obtained using water samples from groundwater monitoring wells. The VZ method is based on the fact that the Sr isotope ratio of soil water just below the surface is often set by dissolution of aeolian material including carbonate, and this ratio is different from the average value in the deeper underlying vadose zone rock matrix. As water infiltrates, the Sr isotopic composition of the water changes toward the rock values as a result of Sr released from the rocks by weathering reactions. The rate of change with depth of the Sr isotope ratio of the vadose zone water is a function ultimately of q/R; the ratio of the infiltration flux (q) to the bulk rock weathering rate (R). Where it is possible to evaluate R, q can be estimated. As data accumulate it may be possible to improve the calibration of the method. At Hanford the vadose zone rock material is mostly unconsolidated sand, silt, and gravel of broadly granitic composition, which constitute the Hanford and Ringold formations. Annual precipitation is about 160 mm/yr. Drilling and coring of a ca. 70m hole to the water table in 1999 as part of the Hanford groundwater monitoring program, in a relatively undisturbed area of the site, allowed us to generate a unique Sr isotope data set. The Sr isotope

  5. Vadose Zone Infiltration Rate at Hanford, Washington, Inferred from Sr Isotope Measurements

    International Nuclear Information System (INIS)

    Maher, Katharine; DePaolo, Donald J.; Conrad, Mark E.; Serne, R. Jeffrey

    2003-01-01

    Sr isotope ratios were measured in the pore water, acid extracts, and sediments of a 70-m vadose zone core to obtain estimates of the long-term infiltration flux for a site in the Hanford/DOE complex in eastern Washington State. The 87Sr/86Sr values of the pore waters decrease systematically with depth, from a high value of 0.721 near the surface toward the bulk sediment average value of 0.711. Estimates of the bulk weathering rate combined with Sr isotopic data were used to constrain the long-term (century to millenial scale) natural diffuse infiltration flux for the site given both steady state and nonsteady state conditions. The models suggest that the infiltration fluc for the site is 7+- 3 mm/yr. The method shows potential for providing long-term in situ estimates of infiltration rates for deep heterogeneous vadose zones

  6. Air Leakage Rates in Typical Air Barrier Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Hun, Diana E. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Atchley, Jerald Allen [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Childs, Phillip W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2016-11-01

    Estimates for 2010 indicate that infiltration in residential buildings was responsible for 2.85 quads of energy (DOE 2014), which is about 3% of the total energy consumed in the US. One of the mechanisms being implemented to reduce this energy penalty is the use of air barriers as part of the building envelope. These technologies decrease airflow through major leakage sites such as oriented strand board (OSB) joints, and gaps around penetrations (e.g., windows, doors, pipes, electrical outlets) as indicated by Hun et al. (2014). However, most air barrier materials do not properly address leakage spots such as wall-to-roof joints and wall-to-foundation joints because these are difficult to seal, and because air barrier manufacturers usually do not provide adequate instructions for these locations. The present study focuses on characterizing typical air leakage sites in wall assemblies with air barrier materials.

  7. Validity and extension of the SCS-CN method for computing infiltration and rainfall-excess rates

    Science.gov (United States)

    Mishra, Surendra Kumar; Singh, Vijay P.

    2004-12-01

    A criterion is developed for determining the validity of the Soil Conservation Service curve number (SCS-CN) method. According to this criterion, the existing SCS-CN method is found to be applicable when the potential maximum retention, S, is less than or equal to twice the total rainfall amount. The criterion is tested using published data of two watersheds. Separating the steady infiltration from capillary infiltration, the method is extended for predicting infiltration and rainfall-excess rates. The extended SCS-CN method is tested using 55 sets of laboratory infiltration data on soils varying from Plainfield sand to Yolo light clay, and the computed and observed infiltration and rainfall-excess rates are found to be in good agreement.

  8. Virus removal during groundwater recharge: effects of infiltration rate on adsorption of poliovirus to soil.

    OpenAIRE

    Vaughn, J M; Landry, E F; Beckwith, C A; Thomas, M Z

    1981-01-01

    Studies were conducted to determine the influence of infiltration rate on poliovirus removal during groundwater recharge with tertiary-treated wastewater effluents. Experiments were conducted at a uniquely designed, field-situated test recharge basin facility through which some 62,000 m3 of sewage had been previously applied. Recharge at high infiltration rates (75 to 100 cm/h) resulted in the movement of considerable numbers of seeded poliovirus to the groundwater. Moderately reduced infiltr...

  9. Difference infiltrometer: a method to measure temporally variable infiltration rates during rainstorms

    Science.gov (United States)

    Moody, John A.; Ebel, Brian A.

    2012-01-01

    We developed a difference infiltrometer to measure time series of non-steady infiltration rates during rainstorms at the point scale. The infiltrometer uses two, tipping bucket rain gages. One gage measures rainfall onto, and the other measures runoff from, a small circular plot about 0.5-m in diameter. The small size allows the infiltration rate to be computed as the difference of the cumulative rainfall and cumulative runoff without having to route water through a large plot. Difference infiltrometers were deployed in an area burned by the 2010 Fourmile Canyon Fire near Boulder, Colorado, USA, and data were collected during the summer of 2011. The difference infiltrometer demonstrated the capability to capture different magnitudes of infiltration rates and temporal variability associated with convective (high intensity, short duration) and cyclonic (low intensity, long duration) rainstorms. Data from the difference infiltrometer were used to estimate saturated hydraulic conductivity of soil affected by the heat from a wildfire. The difference infiltrometer is portable and can be deployed in rugged, steep terrain and does not require the transport of water, as many rainfall simulators require, because it uses natural rainfall. It can be used to assess infiltration models, determine runoff coefficients, identify rainfall depth or rainfall intensity thresholds to initiate runoff, estimate parameters for infiltration models, and compare remediation treatments on disturbed landscapes. The difference infiltrometer can be linked with other types of soil monitoring equipment in long-term studies for detecting temporal and spatial variability at multiple time scales and in nested designs where it can be linked to hillslope and basin-scale runoff responses.

  10. Investigation the effect of outdoor air infiltration on the heat-shielding characteristics the outer walls of high-rise buildings

    Science.gov (United States)

    Vytchikov, Yu. S.; Kostuganov, A. B.; Saparev, M. E.; Belyakov, I. G.

    2018-03-01

    The presented article considers the influence of infiltrated outdoor air on the heat-shielding characteristics of the exterior walls of modern residential and public buildings. A review of the sources devoted to this problem confirmed its relevance at the present time, especially for high-rise buildings. The authors of the article analyzed the effect of longitudinal and transverse air infiltration on the heat-shielding characteristics of the outer wall of a 25-story building that was built in Samara. The results showed a significant reduction of the reduced resistance to the heat transfer of the outer wall when air is infiltrated through it. There are the results of full-scale examination of external walls to confirm the calculated data. Based on the results of the study carried out by the authors of the article, general recommendations on the internal finishing of the outer walls of high-rise buildings are given.

  11. Seasonal changes of the infiltration rates in urban parks of Valencia City, Eastern Spain

    Science.gov (United States)

    Cerdà, Artemi; Keesstra, Saskia; Burguet, María; Pereira, Paulo; Esteban Lucas-Borja, Manuel; Martinez-Murillo, Juan F.

    2016-04-01

    Infiltration is a key process of the hydrological cycle. Infiltration also controls the soil water resources, and the development of the vegetation, and moreover, in the Mediterranean, determines the runoff generation (Cerdà, 1996; 1997; 2001). In the Mediterranean, the infiltration in forest soils shows high spatial variability and seasonal and temporal changes (Cerdà, 1999; Bodí and Cerdà, 2009) and is being affected by forest fires (Cerdà, 1998), which introduce a new temporal change in the seasonality of the infiltration rates. Although the forest soils are well assessed, there is no information about the infiltration in urban areas in Mediterranean cities. The Mediterranean dense urban systems use to be treated as impermeable areas. However, the cities show areas covered by vegetation and with soils that allow the rainfall to infiltrate. Those areas are mainly the parks. In order to shed some light on the infiltration capacity of the soils of the urban area of Valencia city 30 rainfall simulations experiments (Cerdà, 1996) and 90 ring infiltrometer (10 cm diameter) measurements were carried out in January 2011, and they were repeated in July 2011, to compare wet (19.4 % of soil moisture) and dry (5.98 % of soil moisture) soils. The infiltration curves where fitted to the Horton (1933) equation and they lasted for 1 hour. The results show that the infiltration is 11 times higher when measured with ring infiltrometer than with the simulated rainfall at 55 mmh-1, and that the infiltration rates where higher in summer than in winter: 2.01 higher for the ring infiltrometer, and 1.45 higher when measured with the rainfall simulator. In comparison to the soils from the forest areas, the infiltration rate in the gardens were lower, with values of 10.23 and 21.65 mm h-1 in average for winter and summer when measured with the rainfall simulator. Similar results were found with the ring infiltrometer. It was also found a clear relationship between the vegetation

  12. Relative Impacts of Low Permeability Subsurface Deposits on Recharge Basin Infiltration Rates

    Science.gov (United States)

    Oconnell, P.; Becker, M.; Pham, C.; Rodriguez, G.; Hutchinson, A.; Plumlee, M.

    2017-12-01

    Artificial recharge of aquifers through spreading basins has become an important component of water management in semi-arid climates. The rate at which water can be recharged in these basins is limited by the natural vertical permeability of the underlying deposits which may be highly variable both laterally and vertically. To help understand hydrostratigraphic controls on recharge, a newly constructed basin was surveyed and instrumented. Prior to flooding the basin, lithology was characterized by shallow hand coring, direct push coring, ground penetrating radar, and electrical resistivity. After flooding, recharge was monitored through piezometers, electrical resistivity, and a network of fiber optic distributed temperature sensing (DTS). The DTS network used temperature as a tracer to measure infiltration rate on 25 cm intervals both laterally and vertically. Several hundred paired DTS time series datasets (from fiber optic cables located at 0 and 0.5 meters below ground surface) were processed with the cross-wavelet transform (XWT) to calculate spatially and temporally continuous infiltration rates, which can be interpolated and animated to visualize heterogeneity. Time series data from 8-meter deep, vertically oriented DTS cables reveal depth intervals where infiltration rates vary. Inverted resistivity sections from repeated dipole-dipole surveys along the sidewall of a spreading basin exhibit a positive correlation with the distribution of relatively high and low infiltration rates, indicating zones of preferential downward (efficient) and lateral (inefficient) flow, respectively. In contrast to other monitored basins, no perching was observed in the vertically oriented DTS cables. The variation in recharge across the basin and the appearance of subsurface lateral flow can be explained in context of the alluvial depositional environment.

  13. Weather Correlations to Calculate Infiltration Rates for U. S. Commercial Building Energy Models.

    Science.gov (United States)

    Ng, Lisa C; Quiles, Nelson Ojeda; Dols, W Stuart; Emmerich, Steven J

    2018-01-01

    As building envelope performance improves, a greater percentage of building energy loss will occur through envelope leakage. Although the energy impacts of infiltration on building energy use can be significant, current energy simulation software have limited ability to accurately account for envelope infiltration and the impacts of improved airtightness. This paper extends previous work by the National Institute of Standards and Technology that developed a set of EnergyPlus inputs for modeling infiltration in several commercial reference buildings using Chicago weather. The current work includes cities in seven additional climate zones and uses the updated versions of the prototype commercial building types developed by the Pacific Northwest National Laboratory for the U. S. Department of Energy. Comparisons were made between the predicted infiltration rates using three representations of the commercial building types: PNNL EnergyPlus models, CONTAM models, and EnergyPlus models using the infiltration inputs developed in this paper. The newly developed infiltration inputs in EnergyPlus yielded average annual increases of 3 % and 8 % in the HVAC electrical and gas use, respectively, over the original infiltration inputs in the PNNL EnergyPlus models. When analyzing the benefits of building envelope airtightening, greater HVAC energy savings were predicted using the newly developed infiltration inputs in EnergyPlus compared with using the original infiltration inputs. These results indicate that the effects of infiltration on HVAC energy use can be significant and that infiltration can and should be better accounted for in whole-building energy models.

  14. Identifying Housing and Meteorological Conditions Influencing Residential Air Exchange Rates in the DEARS and RIOPA Studies: Development of Distributions for Human Exposure Modeling

    Science.gov (United States)

    Appropriate prediction of residential air exchange rate (AER) is important for estimating human exposures in the residential microenvironment, as AER drives the infiltration of outdoor-generated air pollutants indoors. AER differences among homes may result from a number of fact...

  15. Durability and Performance of High Performance Infiltration Cathodes

    DEFF Research Database (Denmark)

    Samson, Alfred Junio; Søgaard, Martin; Hjalmarsson, Per

    2013-01-01

    The performance and durability of solid oxide fuel cell (SOFC) cathodes consisting of a porous Ce0.9Gd0.1O1.95 (CGO) infiltrated with nitrates corresponding to the nominal compositions La0.6Sr0.4Co1.05O3-δ (LSC), LaCoO3-δ (LC), and Co3O4 are discussed. At 600°C, the polarization resistance, Rp......, varied as: LSC (0.062Ωcm2)cathode was found to depend on the infiltrate firing temperature and is suggested to originate...... of the infiltrate but also from a better surface exchange property. A 450h test of an LSC-infiltrated CGO cathode showed an Rp with final degradation rate of only 11mΩcm2kh-1. An SOFC with an LSC-infiltrated CGO cathode tested for 1,500h at 700°C and 0.5Acm-2 (60% fuel, 20% air utilization) revealed no measurable...

  16. Seasonal Variation of Infiltration Rates in a Managed Aquifer Recharge System: A Belgian Example

    Science.gov (United States)

    Samanta, S.; Sheng, Z.; Munster, C. L.; Houtte, E. V.

    2017-12-01

    Managed Aquifer Recharge (MAR) is a powerful tool in addressing water resources management issues. The Torreele water reuse facility is using MAR to address the problem of water sustainability in a coastal aquifer of Belgium. The Torreele MAR facility uses infiltration ponds to maintain the groundwater level and to prevent saltwater intrusion into the aquifer. The source of recharge is treated wastewater from the Torreele wastewater treatment plant (TWWTP) located 1.2 km inland. The TWWTP uses a state-of-the-art filtration mechanism with a combination of ultrafiltration (UF) and Reverse Osmosis (RO) techniques to assure that recharge water is of very high quality. Data collected at the Torreele MAR facility indicates reduced infiltration rates during the winter season when pond water temperatures vary from 1 to 10ºC. The proposed hypothesis for these lower infiltration rates may be a reduction in hydraulic conductivity due to changes in water viscosity. This study involves the determination of relationship between water temperature, infiltration rates, and hydraulic conductivity at the Torreele MAR facility. The results of this study will lead to an effective administration of the facility and provide an extensive understanding of the system.

  17. Novel approach for evaluation of air change rate in naturally ventilated occupied spaces based on metabolic CO2 time variation

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Markov, Detelin G.

    2014-01-01

    IAQ in many residential buildings relies on non-organized natural ventilation. Accurate evaluation of air change rate (ACR) in this situation is difficult due to the nature of the phenomenon - intermittent infiltration-exfiltration periods of mass exchange between the room air and the outdoor air...... at low rate. This paper describes a new approach for ACR evaluation in naturally ventilated occupied spaces. Actual metabolic CO2 time variation record in an interval of time is compared with the computed variation of metabolic CO2 for the same time interval under reference conditions: sleeping occupants...

  18. Trench infiltration for managed aquifer recharge to permeable bedrock

    Science.gov (United States)

    Heilweil, V.M.; Watt, D.E.

    2011-01-01

    Managed aquifer recharge to permeable bedrock is increasingly being utilized to enhance resources and maintain sustainable groundwater development practices. One such target is the Navajo Sandstone, an extensive regional aquifer located throughout the Colorado Plateau of the western United States. Spreading-basin and bank-filtration projects along the sandstone outcrop's western edge in southwestern Utah have recently been implemented to meet growth-related water demands. This paper reports on a new cost-effective surface-infiltration technique utilizing trenches for enhancing managed aquifer recharge to permeable bedrock. A 48-day infiltration trench experiment on outcropping Navajo Sandstone was conducted to evaluate this alternative surface-spreading artificial recharge method. Final infiltration rates through the bottom of the trench were about 0.5 m/day. These infiltration rates were an order of magnitude higher than rates from a previous surface-spreading experiment at the same site. The higher rates were likely caused by a combination of factors including the removal of lower permeability soil and surficial caliche deposits, access to open vertical sandstone fractures, a reduction in physical clogging associated with silt and biofilm layers, minimizing viscosity effects by maintaining isothermal conditions, minimizing chemical clogging caused by carbonate mineral precipitation associated with algal photosynthesis, and diminished gas clogging associated with trapped air and biogenic gases. This pilot study illustrates the viability of trench infiltration for enhancing surface spreading of managed aquifer recharge to permeable bedrock. ?? 2010.

  19. Measurement of infiltration rates in urban sewer systems by use of oxygen isotopes.

    Science.gov (United States)

    De Bénédittis, J; Bertrand-Krajewski, J L

    2005-01-01

    The paper presents the principle of a method to measure infiltration rates in sewer systems based on the use of oxygen isotopes and its application in Lyon (France). In the urban area of Lyon, significant differences in delta 18O that can reach 3 per thousand are observed between the oxygen isotopic compositions of groundwater originating from Rhone, Saone and from their associated alluvial aquifers. Drinking water supplying Lyon results mainly from pumping in the Rhone alluvial aquifer. Therefore, in some areas, the difference of isotopic composition between wastewater resulting from the consumption of drinking water and local groundwater can be used to measure infiltration in sewer systems. The application in the catchment of Ecully shows that the infiltration flow rate presents strong fluctuations at an hourly scale: it varies between 15 and 40 m3/h. This variability could be explained by non-constant discharges of pumping and by variations of the water level in the sewer.

  20. Estimation of infiltration rate, run-off and sediment yield under ...

    Indian Academy of Sciences (India)

    The main objective of this study is to measure the effect of slope and grass-cover on infiltration rate, run-off ... amongst the plots depending on their slope angle and surface characteristics. An important ... not a new concept amongst the scientists con- ... J. Earth Syst. Sci. ... of various land uses on soil erosion and sediment.

  1. An automated microinfiltrometer to measure small-scale soil water infiltration properties

    Directory of Open Access Journals (Sweden)

    Gordon Dennis C.

    2014-09-01

    Full Text Available We developed an automated miniature constant-head tension infiltrometer that measures very small infiltration rates at millimetre resolution with minimal demands on the operator. The infiltrometer is made of 2.9 mm internal radius glass tube, with an integrated bubbling tower to maintain constant negative head and a porous mesh tip to avoid air-entry. In the bubbling tower, bubble formation and release changes the electrical resistance between two electrodes at the air-inlet. Tests were conducted on repacked sieved sands, sandy loam soil and clay loam soil, packed to a soil bulk density ρd of 1200 kg m-3 or 1400 kg m-3 and tested either air-dried or at a water potential ψ of -50 kPa. The change in water volume in the infiltrometer had a linear relationship with the number of bubbles, allowing bubble rate to be converted to infiltration rate. Sorptivity measured with the infiltrometer was similar between replicates and showed expected differences from soil texture and ρd, varying from 0.15 ± 0.01 (s.e. mm s-1/2 for 1400 kg m-3 clay loam at ψ = -50 kPa to 0.65 ± 0.06 mm s-1/2 for 1200 kg m-3 air dry sandy loam soil. An array of infiltrometers is currently being developed so many measurements can be taken simultaneously.

  2. Numerical modeling of NI-monitored 3D infiltration experiment

    Science.gov (United States)

    Dohnal, Michal; Dusek, Jaromir; Snehota, Michal; Sacha, Jan; Vogel, Tomas; Votrubova, Jana

    2014-05-01

    It is well known that the temporal changes of saturated hydraulic conductivity caused by the occurrence of air phase discontinuities often play an important role in water flow and solute transport experiments. In the present study, a series of infiltration-outflow experiments was conducted to test several working hypotheses about the mechanism of air phase trapping. The experiments were performed on a porous sample with artificial internal structure, using three sandy materials with contrasting hydraulic properties. The sample was axially symmetric with continuous preferential pathways and separate porous matrix blocks (the sample was 3.4 cm in diameter and 8.8 cm high). The infiltration experiments were monitored by neutron imaging (NI). The NI data were then used to quantify the water content of the selected sample regions. The flow regime in the sample was studied using a three-dimensional model based on Richards' equation. The equation was solved by the finite element method. The results of the numerical simulations of the infiltration experiments were compared with the measured outflow rates and with the spatial distribution of water content determined by NI. The research was supported by the Czech Science Foundation Project No. 14-03691S.

  3. Determining Surface Infiltration Rate of Permeable Pavements with Digital Imaging

    Directory of Open Access Journals (Sweden)

    Caterina Valeo

    2018-01-01

    Full Text Available Cell phone images of pervious pavement surfaces were used to explore relationships between surface infiltration rates (SIR measured using the ASTM C1701 standard test and using a simple falling head test. A fiber-reinforced porous asphalt surface and a highly permeable material comprised of stone, rubber and a polymer binder (Porous Pave were tested. Images taken with a high-resolution cellphone camera were acquired as JPEG files and converted to gray scale images in Matlab® for analysis. The distribution of gray levels was compared to the surface infiltration rates obtained for both pavements with attention given to the mean of the distribution. Investigation into the relationships between mean SIR and parameters determined from the gray level distribution produced in the image analysis revealed that mean SIR measured in both pavements were proportional to the inverse of the mean of the distribution. The relationships produced a coefficient of determination over 85% using both the ASTM and the falling head test in the porous asphalt surface. SIR measurements determined with the ASTM method were highly correlated with the inverse mean of the distribution of gray levels in the Porous Pave material as well, producing coefficients of determination of over 90% and Kendall’s tau-b of roughly 70% for nonparametric data.

  4. Rainier Mesa CAU Infiltration Model using INFILv3

    Energy Technology Data Exchange (ETDEWEB)

    Levitt, Daniel G. [Los Alamos National Laboratory; Kwicklis, Edward M. [Los Alamos National Laboratory

    2012-07-13

    The outline of this presentation are: (1) Model Inputs - DEM, Precipitation, Air temp, Soil props, Surface geology, Vegetation; (2) Model Pre-processing - Runoff Routing and sinks, Slope and Azimuth, Soil Ksat reduction with slope (to mitigate bathtub ring), Soil-Bedrock Interface permeabilities; (3) Model Calibration - ET using PEST, Chloride mass balance data, Streamflow using PEST; (4) Model Validation - Streamflow data not used for calibration; (5) Uncertainty Analysis; and (6) Results. Conclusions are: (1) Average annual infiltration rates =11 to 18 mm/year for RM domain; (2) Average annual infiltration rates = 7 to 11 mm/year for SM domain; (3) ET = 70% of precipitation for both domains; (4) Runoff = 8-9% for RM; and 22-24% for SM - Apparently high average runoff is caused by the truncation of the lowerelevation portions of watersheds where much of the infiltration of runoff waters would otherwise occur; (5) Model results are calibrated to measured ET, CMB data, and streamflow observations; (6) Model results are validated using streamflow observations discovered after model calibration was complete; (7) Use of soil Ksat reduction with slope to mitigate bathtub ring was successful (based on calibration results); and (8) Soil-bedrock K{_}interface is innovative approach.

  5. IMPACT OF HEATING AND AIR CONDITIONING SYSTEM OPERATION AND LEAKAGE ON VENTILATION AND INTERCOMPARTMENT TRANSPORT: STUDIES IN UNOCCUPIED AND OCCUPIED TENNESSEE VALLEY HOMES

    Science.gov (United States)

    Forced-air heating and air conditioning (HAC) systems caused an average and maximum increase in air infiltration rates of 1.8- and 4.3-fold, respectively, during brief whole-house studies of tracer gas decay In 39 occupied houses. An average Increase in air infiltration rate of 0...

  6. Long Term Stability Investigation of Solid Oxide Electrolysis Cell with Infiltrated Porous YSZ Air Electrode Under High Current

    DEFF Research Database (Denmark)

    Veltzé, Sune; Ovtar, Simona; Simonsen, Søren Bredmose

    2015-01-01

    stabilised zirconia (YSZ) backbone air electrode and Ni/YSZ cermet fuel electrode. The SOC was tested at electrolysis conditions under high current (up to -1 A/cm2). The porous YSZ electrodes was infiltrated with gadolinium-doped ceria oxide (CGO), to act as a barrier layer between the catalyst...

  7. Evaluation of some infiltration models and hydraulic parameters

    International Nuclear Information System (INIS)

    Haghighi, F.; Gorji, M.; Shorafa, M.; Sarmadian, F.; Mohammadi, M. H.

    2010-01-01

    The evaluation of infiltration characteristics and some parameters of infiltration models such as sorptivity and final steady infiltration rate in soils are important in agriculture. The aim of this study was to evaluate some of the most common models used to estimate final soil infiltration rate. The equality of final infiltration rate with saturated hydraulic conductivity (Ks) was also tested. Moreover, values of the estimated sorptivity from the Philips model were compared to estimates by selected pedotransfer functions (PTFs). The infiltration experiments used the doublering method on soils with two different land uses in the Taleghan watershed of Tehran province, Iran, from September to October, 2007. The infiltration models of Kostiakov-Lewis, Philip two-term and Horton were fitted to observed infiltration data. Some parameters of the models and the coefficient of determination goodness of fit were estimated using MATLAB software. The results showed that, based on comparing measured and model-estimated infiltration rate using root mean squared error (RMSE), Hortons model gave the best prediction of final infiltration rate in the experimental area. Laboratory measured Ks values gave significant differences and higher values than estimated final infiltration rates from the selected models. The estimated final infiltration rate was not equal to laboratory measured Ks values in the study area. Moreover, the estimated sorptivity factor by Philips model was significantly different to those estimated by selected PTFs. It is suggested that the applicability of PTFs is limited to specific, similar conditions. (Author) 37 refs.

  8. Mixed artificial grasslands with more roots improved mine soil infiltration capacity

    Science.gov (United States)

    Wu, Gao-Lin; Yang, Zheng; Cui, Zeng; Liu, Yu; Fang, Nu-Fang; Shi, Zhi-Hua

    2016-04-01

    Soil water is one of the critical limiting factors in achieving sustainable revegetation. Soil infiltration capacity plays a vital role in determining the inputs from precipitation and enhancing water storage, which are important for the maintenance and survival of vegetation patches in arid and semi-arid areas. Our study investigated the effects of different artificial grasslands on soil physical properties and soil infiltration capacity. The artificial grasslands were Medicago sativa, Astragalus adsurgens, Agropyron mongolicum, Lespedeza davurica, Bromus inermis, Hedysarum scoparium, A. mongolicum + Artemisia desertorum, A. adsurgens + A. desertorum and M. sativa + B. inermis. The soil infiltration capacity index (SICI), which was based on the average infiltration rate of stage I (AIRSI) and the average infiltration rate of stage III (AIRS III), was higher (indicating that the infiltration capacity was greater) under the artificial grasslands than that of the bare soil. The SICI of the A. adsurgens + A. desertorum grassland had the highest value (1.48) and bare soil (-0.59) had the lowest value. It was evident that artificial grassland could improve soil infiltration capacity. We also used principal component analysis (PCA) to determine that the main factors that affected SICI were the soil water content at a depth of 20 cm (SWC20), the below-ground root biomasses at depths of 10 and 30 cm (BGB10, BGB30), the capillary porosity at a depth of 10 cm (CP10) and the non-capillary porosity at a depth of 20 cm (NCP20). Our study suggests that the use of Legume-poaceae mixtures and Legume-shrub mixtures to create grasslands provided an effective ecological restoration approach to improve soil infiltration properties due to their greater root biomasses. Furthermore, soil water content, below-ground root biomass, soil capillary porosity and soil non-capillary porosity were the main factors that affect the soil infiltration capacity.

  9. Infiltration and air quality in well-insulated homes: 3. measurement and modeling of pollutant levels

    International Nuclear Information System (INIS)

    Koontz, M.D.; Nagda, N.L.

    1984-01-01

    Indoor pollutant levels in well-insulated houses are being investigated in a 2-year theoretical and experimental study involving the simultaneous measurement of meteorological variables, air exchange and circulation, and energy consumption. This paper describes concentrations of radon, radon progeny, formaldehyde, carbon monoxide, and nitrogen oxides observed in two houses over two seasons, summer and fall 1983. Two companion papers provide a perspective on the problem and the study design, and present results of energy use and infiltration measurements. (Author)

  10. Application of spreadsheet to estimate infiltration parameters

    Directory of Open Access Journals (Sweden)

    Mohammad Zakwan

    2016-09-01

    Full Text Available Infiltration is the process of flow of water into the ground through the soil surface. Soil water although contributes a negligible fraction of total water present on earth surface, but is of utmost importance for plant life. Estimation of infiltration rates is of paramount importance for estimation of effective rainfall, groundwater recharge, and designing of irrigation systems. Numerous infiltration models are in use for estimation of infiltration rates. The conventional graphical approach for estimation of infiltration parameters often fails to estimate the infiltration parameters precisely. The generalised reduced gradient (GRG solver is reported to be a powerful tool for estimating parameters of nonlinear equations and it has, therefore, been implemented to estimate the infiltration parameters in the present paper. Field data of infiltration rate available in literature for sandy loam soils of Umuahia, Nigeria were used to evaluate the performance of GRG solver. A comparative study of graphical method and GRG solver shows that the performance of GRG solver is better than that of conventional graphical method for estimation of infiltration rates. Further, the performance of Kostiakov model has been found to be better than the Horton and Philip's model in most of the cases based on both the approaches of parameter estimation.

  11. Effect of seawater on consistency, infiltration rate and swelling characteristics of montmorillonite clay

    Directory of Open Access Journals (Sweden)

    Mohie Eldin Elmashad

    2016-08-01

    Full Text Available This paper presents the results of an experimental investigation performed to quantify the effect of mixing clayey soils with saltwater on consistency and swelling characteristics of clays. Massive natural clay deposits and compacted clay backfills either exist or are used in certain important and sensitive applications such as dams, liners, barriers and buffers in waste disposal facilities. In many cases, the clay deposits in these applications are subjected to saltwater. However, in standard laboratory classification tests, distilled or potable water are usually used in mixing test samples. This may lead to faulty interpretation of the actual in-situ consistency and volume change behaviors. In this research, an attempt is made to quantify the changes in consistency and swelling of clay soils from various locations around the Nile valley and possessing a wide range of consistency, when mixed with natural seawater with different salt concentrations. The results showed that the increase of the salt concentration of the mixing water may result in major decrease in the liquid limit and swelling characteristics of high plasticity montmorillonite clays. The reduction in the swelling of the clay soils is also proportional to the rate of saltwater infiltration. In an attempt to correlate the swelling of clays to the rate of water infiltration, a new simplified laboratory apparatus is proposed where swelling and infiltration are measured in one simple test “the swelling infiltrometer”.

  12. Water infiltration into homogeneous soils: a new concept

    International Nuclear Information System (INIS)

    Manfredni, S.

    1977-10-01

    A new concept for the analytical description of the process of water infiltration into homogeneous soils is presented. The concept uses a new definition of a 'gravitational diffusivity' which permits the generalization of both cases, horizontal and vertical infiltration. The efficiency of the new concept in describing the infiltration process, for short and intermediate times, is proved through experimental data obtained during water infiltration into air-dry soil columns. Its advantages are discussed comparing soil water contents predicted by the numerical solution proposed by PHILLIP (1955, 1957) [pt

  13. Effect of irrigation with treated wastewater on soil chemical properties and infiltration rate.

    Science.gov (United States)

    Bedbabis, Saida; Ben Rouina, Béchir; Boukhris, Makki; Ferrara, Giuseppe

    2014-01-15

    In Tunisia, water scarcity is one of the major constraints for agricultural activities. The reuse of treated wastewater (TWW) in agriculture can be a sustainable solution to face water scarcity. The research was conducted for a period of four years in an olive orchard planted on a sandy soil and subjected to irrigation treatments: a) rain-fed conditions (RF), as control b) well water (WW) and c) treated wastewater (TWW). In WW and TWW treatments, an annual amount of 5000 m(3) ha(-1) of water was supplied to the orchard. Soil samples were collected at the beginning of the study and after four years for each treatment. The main soil properties such as electrical conductivity (EC), pH, soluble cations, chloride (Cl(-)), sodium adsorption ratio (SAR), organic matter (OM) as well as the infiltration rate were investigated. After four years, either a significant decrease of pH and infiltration rate or a significant increase of OM, SAR and EC were observed in the soil subjected to treated wastewater treatment. Copyright © 2013. Published by Elsevier Ltd.

  14. Application of spreadsheet to estimate infiltration parameters

    OpenAIRE

    Zakwan, Mohammad; Muzzammil, Mohammad; Alam, Javed

    2016-01-01

    Infiltration is the process of flow of water into the ground through the soil surface. Soil water although contributes a negligible fraction of total water present on earth surface, but is of utmost importance for plant life. Estimation of infiltration rates is of paramount importance for estimation of effective rainfall, groundwater recharge, and designing of irrigation systems. Numerous infiltration models are in use for estimation of infiltration rates. The conventional graphical approach ...

  15. Indoor Levels of Formaldehyde and Other Pollutants and Relationship to Air Exchange Rates and Human Activities

    Science.gov (United States)

    Huangfu, Y.; O'Keeffe, P.; Kirk, M.; Walden, V. P.; Lamb, B. K.; Jobson, B. T.

    2017-12-01

    This paper reports results on an indoor air quality study conducted on six homes in summer and winter, contrasting indoor and outdoor concentrations of O3, CO, CO2, NOx, PM2.5, and selected volatile organic hydrocarbons measured by PTR-MS. Data were collected as 1 minute averages. Air exchange rates of the homes were determined by CO2 tracer release. Smart home sensors, recording human activity level in various places in the home, and window and doors openings, were utilized to better understand the link between human activity and indoor air pollution. From our study, averaged air exchange rates of the homes ranged from 0.2 to 1.2 hour-1 and were greatly affected by the ventilation system type and window and door openings. In general, a negative correlation between air exchange rate and indoor VOCs levels was observed, with large variation of pollutant levels between the homes. For most of the VOCs measured in the house, including formaldehyde and acetaldehyde, summer levels were much higher than winter levels. In some homes formaldehyde levels displayed a time of day variation that was linked to changes in indoor temperature. During a wildfire period in the summer of 2015, outdoor levels of PM2.5, formaldehyde, and benzene dramatically increased, significantly impacting indoor levels due to infiltration. Human activities, such as cooking, can significantly change the levels of most of the compounds measured in the house and the levels can be significantly elevated for short periods of time, with peak levels can be several orders higher compared with typical levels. The data suggest that an outcome of state energy codes that require new homes to be energy efficient, and as a consequence built with lower air exchange rates, will be unacceptable levels of air toxics, notably formaldehyde.

  16. A simple analytical infiltration model for short-duration rainfall

    Science.gov (United States)

    Wang, Kaiwen; Yang, Xiaohua; Liu, Xiaomang; Liu, Changming

    2017-12-01

    Many infiltration models have been proposed to simulate infiltration process. Different initial soil conditions and non-uniform initial water content can lead to infiltration simulation errors, especially for short-duration rainfall (SHR). Few infiltration models are specifically derived to eliminate the errors caused by the complex initial soil conditions. We present a simple analytical infiltration model for SHR infiltration simulation, i.e., Short-duration Infiltration Process model (SHIP model). The infiltration simulated by 5 models (i.e., SHIP (high) model, SHIP (middle) model, SHIP (low) model, Philip model and Parlange model) were compared based on numerical experiments and soil column experiments. In numerical experiments, SHIP (middle) and Parlange models had robust solutions for SHR infiltration simulation of 12 typical soils under different initial soil conditions. The absolute values of percent bias were less than 12% and the values of Nash and Sutcliffe efficiency were greater than 0.83. Additionally, in soil column experiments, infiltration rate fluctuated in a range because of non-uniform initial water content. SHIP (high) and SHIP (low) models can simulate an infiltration range, which successfully covered the fluctuation range of the observed infiltration rate. According to the robustness of solutions and the coverage of fluctuation range of infiltration rate, SHIP model can be integrated into hydrologic models to simulate SHR infiltration process and benefit the flood forecast.

  17. Spatiotemporally resolved air exchange rate as a modifier of acute air pollution-related morbidity in Atlanta.

    Science.gov (United States)

    Sarnat, Jeremy A; Sarnat, Stefanie Ebelt; Flanders, W Dana; Chang, Howard H; Mulholland, James; Baxter, Lisa; Isakov, Vlad; Özkaynak, Halûk

    2013-01-01

    Epidemiological studies frequently use central site concentrations as surrogates of exposure to air pollutants. Variability in air pollutant infiltration due to differential air exchange rates (AERs) is potentially a major factor affecting the relationship between central site concentrations and actual exposure, and may thus influence observed health risk estimates. In this analysis, we examined AER as an effect modifier of associations between several urban air pollutants and corresponding emergency department (ED) visits for asthma and wheeze during a 4-year study period (January 1999-December 2002) for a 186 ZIP code area in metro Atlanta. We found positive associations for the interaction between AER and pollution on asthma ED visits for both carbon monoxide (CO) and nitrogen oxides (NO(x)), indicating significant or near-significant effect modification by AER on the pollutant risk-ratio estimates. In contrast, the interaction term between particulate matter (PM)(2.5) and AER on asthma ED visits was negative and significant. However, alternative distributional tertile analyses showed PM(2.5) and AER epidemiological model results to be similar to those found for NOx and CO (namely, increasing risk ratios (RRs) with increasing AERs when ambient PM(2.5) concentrations were below the highest tertile of their distribution). Despite the fact that ozone (O(3)) was a strong independent predictor of asthma ED visits in our main analysis, we found no O(3)-AER effect modification. To our knowledge, our findings for CO, NOx, and PM(2.5) are the first to provide an indication of short-term (i.e., daily) effect modification of multiple air pollution-related risk associations with daily changes in AER. Although limited to one outcome category in a single large urban locale, the findings suggest that the use of relatively simple and easy-to-derive AER surrogates may reflect intraurban differences in short-term exposures to pollutants of ambient origin.

  18. Infiltration rate performance of buildings in the historic centre of Oporto

    Directory of Open Access Journals (Sweden)

    Alves, S.

    2014-09-01

    Full Text Available This work is part of a major investigation the authors are undertaking aiming to evaluate the energy performance of different retrofitting strategies for housing buildings, in order to establish preferential criteria of intervention according to its climate zone location, morphology, constructive features and patrimonial values. In the historic centre of Oporto, one of the major actions resides on a significant reduction in the heating loads of these distinctive buildings by decreasing the windows infiltration rate. To be able to accurate this potential for energy savings, in situ measurements of the infiltration rate of this houses at present were required, previous to a possible intervention. This article presents the data obtained using a fan pressurization method in two non-refurbished characteristic buildings of the Oporto’s Historic Centre, and analyses the results obtained for both a typical sash window and a casement window. Some relations between these infiltration rates and the buildings morphological and typological characteristics are considered.Este trabajo forma parte de una investigación mayor que los autores están llevando a cabo y que tiene como objetivo evaluar la eficiencia energética de diferentes estrategias de rehabilitación de edificios de viviendas, con el fin de establecer criterios preferenciales de intervención de acuerdo a la zona climáticas donde se ubica, a la morfología de los edificios, a sus características constructivas y a sus valores patrimoniales. En el centro histórico de Oporto, una de las principales acciones consistiría en la reducción significativa de la demanda de calefacción en los edificios de viviendas que lo caracterizan, mediante la disminución de la tasa de infiltración de las ventanas. Para poder precisar este potencial de ahorro de energía, se requieren mediciones in situ de las tasas de infiltración de las citadas viviendas en su estado actual, previamente a una posible

  19. A MODFLOW Infiltration Device Package for Simulating Storm Water Infiltration.

    Science.gov (United States)

    Jeppesen, Jan; Christensen, Steen

    2015-01-01

    This article describes a MODFLOW Infiltration Device (INFD) Package that can simulate infiltration devices and their two-way interaction with groundwater. The INFD Package relies on a water balance including inflow of storm water, leakage-like seepage through the device faces, overflow, and change in storage. The water balance for the device can be simulated in multiple INFD time steps within a single MODFLOW time step, and infiltration from the device can be routed through the unsaturated zone to the groundwater table. A benchmark test shows that the INFD Package's analytical solution for stage computes exact results for transient behavior. To achieve similar accuracy by the numerical solution of the MODFLOW Surface-Water Routing (SWR1) Process requires many small time steps. Furthermore, the INFD Package includes an improved representation of flow through the INFD sides that results in lower infiltration rates than simulated by SWR1. The INFD Package is also demonstrated in a transient simulation of a hypothetical catchment where two devices interact differently with groundwater. This simulation demonstrates that device and groundwater interaction depends on the thickness of the unsaturated zone because a shallow groundwater table (a likely result from storm water infiltration itself) may occupy retention volume, whereas a thick unsaturated zone may cause a phase shift and a change of amplitude in groundwater table response to a change of infiltration. We thus find that the INFD Package accommodates the simulation of infiltration devices and groundwater in an integrated manner on small as well as large spatial and temporal scales. © 2014, National Ground Water Association.

  20. Air quality in low-ventilated museum storage buildings

    DEFF Research Database (Denmark)

    Ryhl-Svendsen, Morten; Aasbjerg Jensen, Lars; Klenz Larsen, Poul

    2014-01-01

    Modern low-energy museum storage buildings are often designed for a low air exchange rate, on the order of less than 1 exchange per day. We investigated how this affected the indoor air quality in six Danish museum storage buildings. The infiltration of ambient pollutants, and the level to which...... internally-generated pollutants accumulate, were measured by passive sampling of ozone, nitrogen dioxide, and organic acids. The air exchange rates and the interchange of air between storage rooms were measured by the per-fluorocarbon tracer gas method. Ambient pollutants were reduced in concentration...

  1. Effect of Ru/CGO versus Ni/CGO Co- Infiltration on the Performance and Stability of STN-Based SOFCs

    DEFF Research Database (Denmark)

    Ramos, Tania; Veltzé, Sune; Sudireddy, Bhaskar Reddy

    2014-01-01

    /CGO infiltrated cell reached ∼0.7 W cm–2 at 850 °C, 4% H2O/H2, whereas the Ni/CGO infiltrated cell reached ∼0.3 W cm–2, with the current morphologies and loadings. Operation at 0.125 A cm–2, 850 °C, feeding 50% H2O/H2 to the anode and air to the cathode, for a period >300 h, showed superior stability for the Ru....../CGO infiltrated cell, with ∼0.04 mV h–1 degradation rate, when compared to the Ni/CGO infiltrated cell (∼0.5 mV h–1). For the Ni/CGO case, the observed degradation has been tentatively linked to initial changes in the electrochemical active area and longterm detrimental interactions between components....

  2. Influence of Surface Biosolids Application on Infiltration

    Directory of Open Access Journals (Sweden)

    Richard E. Zartman

    2012-01-01

    Full Text Available Biosolids from waste water treatment facilities applied to soils not only add plant nutrients, but also increase infiltration and decrease runoff and erosion. Wet biosolids from New York, NY, were surface applied at 0 to 90 Mg ha−1 dry weight to soils near El Paso, Tex. Simulated rainfall intensities of 16.4 cm hr−1 for 30 minutes applied to 0.5 m2 soil plots yielded initial infiltration rates of ~16 cm hr−1 for all plots. Biosolids applications extended the duration of the initially high infiltration rates. After 30 minutes, infiltration rates for bare soil were 3 cm hr−1 without and 10 cm hr−1 with 90 Mg biosolids ha−1. Applied biosolids, plant litter, surface gravel, and plant base contributed surface cover, which absorbed raindrop energy and reduced erosion. Biosolids increased cumulative infiltration on the vegetated, wet soils more than for the dry or bare soils. Biosolids increased cumulative infiltration from 2 to 6 cm on a bare gravelly soil and from 9.3 to 10.6 cm on a vegetated soil.

  3. Comparison of infiltration models in NIT Kurukshetra campus

    Science.gov (United States)

    Singh, Balraj; Sihag, Parveen; Singh, Karan

    2018-05-01

    The aim of the present investigation is to evaluate the performance of infiltration models used to calculate the infiltration rate of the soils. Ten different locations were chosen to measure the infiltration rate in NIT Kurukshetra. The instrument used for the experimentation was double ring infiltrometer. Some of the popular infiltration models like Horton's, Philip's, Modified Philip's and Green-Ampt were fitted with infiltration test data and performance of the models was determined using Nash-Sutcliffe efficiency (NSE), coefficient of correlation (C.C) and Root mean square error (RMSE) criteria. The result suggests that Modified Philip's model is the most accurate model where values of C.C, NSE and RMSE vary from 0.9947-0.9999, 0.9877-0.9998 to 0.1402-0.6913 (mm/h), respectively. Thus, this model can be used to synthetically produce infiltration data in the absence of infiltration data under the same conditions.

  4. Atrazine distribution measured in soil and leachate following infiltration conditions.

    Science.gov (United States)

    Neurath, Susan K; Sadeghi, Ali M; Shirmohammadi, Adel; Isensee, Allan R; Torrents, Alba

    2004-01-01

    Atrazine transport through packed 10 cm soil columns representative of the 0-10 cm soil horizon was observed by measuring the atrazine recovery in the total leachate volume, and upper and lower soil layers following infiltration of 7.5 cm water using a mechanical vacuum extractor (MVE). Measured recoveries were analyzed to understand the influence of infiltration rate and delay time on atrazine transport and distribution in the column. Four time periods (0.28, 0.8, 1.8, and 5.5 h) representing very high to moderate infiltration rates (26.8, 9.4, 4.2, and 1.4 cm/h) were used. Replicate soil columns were tested immediately and following a 2-d delay after atrazine application. Results indicate atrazine recovery in leachate was independent of infiltration rate, but significantly lower for infiltration following a 2-d delay. Atrazine distribution in the 0-1 and 9-10 cm soil layers was affected by both infiltration rate and delay. These results are in contrast with previous field and laboratory studies that suggest that atrazine recovery in the leachate increases with increasing infiltration rate. It appears that the difference in atrazine recovery measured using the MVE and other leaching experiments using intact soil cores from this field site and the rain simulation equipment probably illustrates the effect of infiltrating water interacting with the atrazine present on the soil surface. This work suggests that atrazine mobilization from the soil surface is also dependent on interactions of the infiltrating water with the soil surface, in addition to the rate of infiltration through the surface soil.

  5. Using Reflectance Spectroscopy and Artificial Neural Network to Assess Water Infiltration Rate into the Soil Profile

    Directory of Open Access Journals (Sweden)

    Naftali Goldshleger

    2012-01-01

    Full Text Available We explored the effect of raindrop energy on both water infiltration into soil and the soil's NIR-SWIR spectral reflectance (1200–2400 nm. Seven soils with different physical and morphological properties from Israel and the US were subjected to an artificial rainstorm. The spectral properties of the crust formed on the soil surface were analyzed using an artificial neural network (ANN. Results were compared to a study with the same population in which partial least-squares (PLS regression was applied. It was concluded that both models (PLS regression and ANN are generic as they are based on properties that correlate with the physical crust, such as clay content, water content and organic matter. Nonetheless, better results for the connection between infiltration rate and spectral properties were achieved with the non-linear ANN technique in terms of statistical values (RMSE of 17.3% for PLS regression and 10% for ANN. Furthermore, although both models were run at the selected wavelengths and their accuracy was assessed with an independent external group of samples, no pre-processing procedure was applied to the reflectance data when using ANN. As the relationship between infiltration rate and soil reflectance is not linear, ANN methods have the advantage for examining this relationship when many soils are being analyzed.

  6. Water filtration rate and infiltration/accumulation of low density lipoproteins in 3 different modes of endothelial/smooth muscle cell co-cultures.

    Science.gov (United States)

    Ding, ZuFeng; Fan, YuBo; Deng, XiaoYan

    2009-11-01

    Using different endothelial/smooth muscle cell co-culture modes to simulate the intimal structure of blood vessels, the water filtration rate and the infiltration/accumulation of LDL of the cultured cell layers were studied. The three cell culture modes of the study were: (i) The endothelial cell monolayer (EC/Phi); (ii) endothelial cells directly co-cultured on the smooth muscle cell monolayer (EC-SMC); (iii) endothelial cells and smooth muscle cells cultured on different sides of a Millicell-CM membrane (EC/SMC). It was found that under the same condition, the water filtration rate was the lowest for the EC/SMC mode and the highest for the EC/Phi mode, while the infiltration/accumulation of DiI-LDLs was the lowest in the EC/Phi mode and the highest in the EC-SMC mode. It was also found that DiI-LDL infiltration/accumulation in the cultured cell layers increased with the increasing water filtration rate. The results from the in vitro model study therefore suggest that the infiltration/accumulation of the lipids within the arterial wall is positively correlated with concentration polarization of atherogenic lipids, and the integrity of the endothelium plays an important role in the penetration and accumulation of atherogenic lipids in blood vessel walls.

  7. Spatial and temporal infiltration dynamics during managed aquifer recharge.

    Science.gov (United States)

    Racz, Andrew J; Fisher, Andrew T; Schmidt, Calla M; Lockwood, Brian S; Los Huertos, Marc

    2012-01-01

    Natural groundwater recharge is inherently difficult to quantify and predict, largely because it comprises a series of processes that are spatially distributed and temporally variable. Infiltration ponds used for managed aquifer recharge (MAR) provide an opportunity to quantify recharge processes across multiple scales under semi-controlled conditions. We instrumented a 3-ha MAR infiltration pond to measure and compare infiltration patterns determined using whole-pond and point-specific methods. Whole-pond infiltration was determined by closing a transient water budget (accounting for inputs, outputs, and changes in storage), whereas point-specific infiltration rates were determined using heat as a tracer and time series analysis at eight locations in the base of the pond. Whole-pond infiltration, normalized for wetted area, rose rapidly to more than 1.0 m/d at the start of MAR operations (increasing as pond stage rose), was sustained at high rates for the next 40 d, and then decreased to less than 0.1 m/d by the end of the recharge season. Point-specific infiltration rates indicated high spatial and temporal variability, with the mean of measured values generally being lower than rates indicated by whole-pond calculations. Colocated measurements of head gradients within saturated soils below the pond were combined with infiltration rates to calculate soil hydraulic conductivity. Observations indicate a brief period of increasing saturated hydraulic conductivity, followed by a decrease of one to two orders of magnitude during the next 50 to 75 d. Locations indicating the most rapid infiltration shifted laterally during MAR operation, and we suggest that infiltration may function as a "variable source area" processes, conceptually similar to catchment runoff. © 2011, The Author(s). Ground Water © 2011, National Ground Water Association.

  8. Water infiltration in an ultisol after cultivation of common bean

    Directory of Open Access Journals (Sweden)

    Maria Aparecida do Nascimento dos Santos

    2014-10-01

    Full Text Available Water infiltration in the soil is an important hydrological process that occurs at the interface of the soil-atmosphere system; thus, the soil management practice used has a strong influence on this process. The aim of this study was to evaluate water infiltration in the soil and compare equations for estimating the water infiltration rate in an Ultisol after harvesting common bean (Phaseolus vulgaris L. under simulated rainfall. Field tests with a rainfall simulator were carried out in three soil management systems: minimum tillage (MT, conventional tillage (CT, and no tillage (NT. In NT, four levels of plant residue on the soil surface were evaluated: 0, 3, 6, and 9 t ha-1. The models of Kostiakov-Lewis, Horton, and Philip were used to estimate the infiltration rate. In the MT system, the final infiltration rate was 54 mm h-1, whereas in the CT and NT systems with up to 3 t ha-1 of plant residue on the soil surface, the rate was near 17 mm h-1. In addition, the results indicated that in the NT system the infiltration rate increased with plant residue coverage greater than 6 t ha-1, i.e., there was a positive correlation between plant cover and the water infiltration rate. The Horton model was the most suitable in representing the water infiltration process in the soil. Therefore, this model can be recommended for estimation of this variable regardless of the soil tillage system used.

  9. Immunophenotypic features of tumor infiltrating lymphocytes from mammary carcinomas in female dogs associated with prognostic factors and survival rates

    International Nuclear Information System (INIS)

    Estrela-Lima, Alessandra; Araújo, Márcio SS; Costa-Neto, João M; Teixeira-Carvalho, Andréa; Barrouin-Melo, Stella M; Cardoso, Sergio V; Martins-Filho, Olindo A; Serakides, Rogéria; Cassali, Geovanni D

    2010-01-01

    The immune system plays an important role in the multifactorial biologic system during the development of neoplasias. However, the involvement of the inflammatory response in the promotion/control of malignant cells is still controversial, and the cell subsets and the mechanisms involved are poorly investigated. The goal of this study was to characterize the clinical-pathological status and the immunophenotyping profile of tumor infiltrating lymphocytes and their association with the animal survival rates in canine mammary carcinomas. Fifty-one animals with mammary carcinomas, classified as carcinomas in mixed tumors-MC-BMT = 31 and carcinomas-MC = 20 were submitted to systematic clinical-pathological analysis (tumor size; presence of lymph node and pulmonary metastasis; clinical stage; histological grade; inflammatory distribution and intensity as well as the lymphocytic infiltrate intensity) and survival rates. Twenty-four animals (MC-BMT = 16 and MC = 8) were elected to the immunophenotypic study performed by flow cytometry. Data analysis demonstrated that clinical stage II-IV and histological grade was I more frequent in MC-BMT as compared to MC. Univariate analysis demonstrated that the intensity of inflammation (moderate/intense) and the proportion of CD4 + (≥ 66.7%) or CD8 + T-cells (<33.3%) were not associated with worse survival rate. Multivariate analysis demonstrated that only lymphocytic infiltrate intensity ≥ 600 (P = 0.02) remained as independent prognostic factor. Despite the clinical manifestation, the lymphocytes represented the predominant cell type in the tumor infiltrate. The percentage of T-cells was higher in animals with MC-BMT without metastasis, while the percentage of B-lymphocytes was greater in animals with metastasized MC-BMT (P < 0.05). The relative percentage of CD4 + T-cells was significantly greater in metastasized tumors (both MC-BMT and MC), (P < 0.05) while the proportion of CD8 + T-cells was higher in MC-BMT without

  10. Assessing the Impact of Recycled Water Quality and Clogging on Infiltration Rates at A Pioneering Soil Aquifer Treatment (SAT) Site in Alice Springs, Northern Territory (NT), Australia

    OpenAIRE

    Karen E. Barry; Joanne L. Vanderzalm; Konrad Miotlinski; Peter J. Dillon

    2017-01-01

    Infiltration techniques for managed aquifer recharge (MAR), such as soil aquifer treatment (SAT) can facilitate low-cost water recycling and supplement groundwater resources. However there are still challenges in sustaining adequate infiltration rates in the presence of lower permeability sediments, especially when wastewater containing suspended solids and nutrients is used to recharge the aquifer. To gain a better insight into reductions in infiltration rates during MAR, a field investigati...

  11. Modelling spatial distribution of soil steady state infiltration rate in an urban park (Vingis Parkas, Vilnius, Lithuania)

    Science.gov (United States)

    Pereira, Paulo; Cerda, Artemi; Depellegrin, Daniel; Misiune, Ieva; Bogunovic, Igor; Menchov, Oleksandr

    2016-04-01

    infiltration rate was 69 mm h-1, with a minimum of 12.72 mm h-1 and a maximum of 692.31 mm h-1. The spatial variability was extremely high (coefficient of variation of 153.71). Among the methods tested the most accurate was SK (RMSE=0.542) and the least precise TPS (RMSE=0.695). With the exception of the IDW5, all the correlations between observed and estimated values were significant at a p<0.05. All the residuals followed the normal distribution. Steady state infiltration was high in the southern and central part of the plot (where the human impact is high) and low in the northern part of the park, where forests are denser. References Bisantino, T., Bingner, R., Chouaib, W., Gentile, F., Trisorio Liuzzi, G. (2015) Estimation of runoff, peak discharge and sediment load at the event scale in a medium-size mediterranean watershed using the annagnps model Land Degradation and Development, 26, 340-355. Brevik, E. C., Cerdà, A., Mataix-Solera, J., Pereg, L., Quinton, J. N., Six, J., Van Oost, K. (2015) The interdisciplinary nature of SOIL. SOIL, 1, 117-129. Cassinari, C., Manfredi, P., Giupponi, L., Trevisan, M., Piccini, C. (2015). Relationship between hydraulic properties and plant coverage of the closed-landfill soils in Piacenza (Po Valley, Italy). Solid Earth, 6, 929-943. Cerdà, A. (1996) Seasonal variability of infiltration rates under contrasting slope conditions in southeast Spain. Geoderma, 69, 217-232. Cerdà, A., González-Pelayo, O., Giménez-Morera, A., Jordán, A., Pereira, P., Novara, A., Brevik, E.C., Prosdocimi, M., Mahmoodabadi, M., Keesstra, S., García Orenes, F., Ritsema, C. (2015) The use of barley straw residues to avoid high erosion and runoff rates on persimmon plantations in Eastern Spain under low frequency - high magnitude simulated rainfall events. Soil Research (In press) Cerdà, A. (2001) Effects of rock fragment cover on soil infiltration, interrill runoff and erosion. European Journal of Soil Science, 52, 59-68. Cerdà, A. (1997) Seasonal changes

  12. Air dose rate in Aichi Prefecture

    International Nuclear Information System (INIS)

    Ohnuma, Shoko; Chaya, Kunio; Tomita, Banichi; Aoyama, Kan; Yamada, Naoki; Yamada, Masuo; Hamamura, Norikatsu

    1985-01-01

    We have carried out the observations of air dose rate during 1964--1983 at the fixed points of Aichi Prefecture and investigated the distribution of air dose rate in this prefecture during 1979--1983. The results of these researches are as follows. 1) The apparent half time of radiation dose from the earth and the atmosphere during the last 20 years was about 9.7 years and it was longer than the apparent half time of fallout total β radioactivity in every rainfall that was about 3.2 years. 2) The influence of nuclear explosion test in China on the measurements of air does rate did not existed directly during the latter half of 20 years, not so as during the former and it was keeping decreasing. It was expected that the air dose rate would begin to indicate the natural radiation dose from the earth and the atmosphere in the near future. 3) The distribution of air dose rate in this prefecture depended strongly on the geology. The maximum value was 5.6 μR/hr (except cosmic rays) in Fujioka Cho, the minimum value was 1.9 μR/hr (except cosmic rays) in Tahara Cho and the average in the whole prefecture was 3.5+-0.7 μR/hr (except cosmic rays). 4) It was estimated that the radiation dose which the inhabitants received from the earth and the atmosphere was 17--52 m rem a year and the average was 31 m rem a year. (author)

  13. Air dose rate in Aichi Prefecture

    Energy Technology Data Exchange (ETDEWEB)

    Ohnuma, Shoko; Chaya, Kunio; Tomita, Banichi; Aoyama, Kan; Yamada, Naoki; Yamada, Masuo; Hamamura, Norikatsu

    1985-03-01

    We have carried out the observations of air dose rate during 1964-1983 at the fixed points of Aichi Prefecture and investigated the distribution of air dose rate in this prefecture during 1979-1983. The results of these researches are as follows. 1) The apparent half time of radiation dose from the earth and the atmosphere during the last 20 years was about 9.7 years and it was longer than the apparent half time of fallout total ..beta.. radioactivity in every rainfall that was about 3.2 years. 2) The influence of nuclear explosion test in China on the measurements of air does rate did not existed directly during the latter half of 20 years, not so as during the former and it was keeping decreasing. It was expected that the air dose rate would begin to indicate the natural radiation dose from the earth and the atmosphere in the near future. 3) The distribution of air dose rate in this prefecture depended strongly on the geology. The maximum value was 5.6 ..mu..R/hr (except cosmic rays) in Fujioka Cho, the minimum value was 1.9 ..mu..R/hr (except cosmic rays) in Tahara Cho and the average in the whole prefecture was 3.5 +- 0.7 ..mu..R/hr (except cosmic rays). 4) It was estimated that the radiation dose which the inhabitants received from the earth and the atmosphere was 17-52 m rem a year and the average was 31 m rem a year.

  14. Focused Flow During Infiltration Into Ethanol-Contaminated Unsaturated Porous Media

    Science.gov (United States)

    Jazwiec, A.; Smith, J. E.

    2017-12-01

    The increasing commercial and industrial use of ethanol, e.g. in biofuels, has generated increased incidents of vadose zone contamination by way of ethanol spills and releases. This has increased the interest in better understanding behaviors of ethanol in unsaturated porous media and it's multiphase interactions in the vadose zone. This study uses highly controlled laboratory experiments in a 2-D (0.6mx0.6mx0.01m) flow cell to investigate water infiltration behaviors into ethanol-contaminated porous media. Ethanol and water were applied by either constant head or constant flux methods onto the surface of sands homogenously packed into the flow cell. The constant flux experiments at both low and high application rates were conducted using a rainulator with a row of hypodermic needles connected to a peristaltic pump. The constant head experiments were conducted using an 8cm diameter tension disk infiltrometer set to both low and high tensions. The presence of ethanol contamination generated solute-dependent capillarity induced focused flow (SCIFF) of water infiltration, which was primarily due to decreases in interfacial tensions at the air-liquid interfaces in the unsaturated sands as a function of ethanol concentration. SCIFF was clearly expressed as an unsaturated water flow phenomenon comprised of narrowly focused vertical flow fingers of water within the initially ethanol contaminated porous media. Using analyses of photos and video, comparisons were made between constant flux and constant head application methods. Further comparisons were made between low and high infiltration rates and the two sand textures used. A high degree of sensitivity to minor heterogeneity in relatively homogeneous sands was also observed. The results of this research have implications for rainfall infiltration into ethanol contaminated vadose zones expressing SCIFF, including implications for associated mass fluxes and the nature of flushing of ethanol from the unsaturated zone to

  15. Assessing the Impact of Recycled Water Quality and Clogging on Infiltration Rates at A Pioneering Soil Aquifer Treatment (SAT Site in Alice Springs, Northern Territory (NT, Australia

    Directory of Open Access Journals (Sweden)

    Karen E. Barry

    2017-03-01

    Full Text Available Infiltration techniques for managed aquifer recharge (MAR, such as soil aquifer treatment (SAT can facilitate low-cost water recycling and supplement groundwater resources. However there are still challenges in sustaining adequate infiltration rates in the presence of lower permeability sediments, especially when wastewater containing suspended solids and nutrients is used to recharge the aquifer. To gain a better insight into reductions in infiltration rates during MAR, a field investigation was carried out via soil aquifer treatment (SAT using recharge basins located within a mixture of fine and coarse grained riverine deposits in Alice Springs, Northern Territory, Australia. A total of 2.6 Mm3 was delivered via five SAT basins over six years; this evaluation focused on three years of operation (2011–2014, recharging 1.5 Mm3 treated wastewater via an expanded recharge area of approximately 38,400 m2. Average infiltration rates per basin varied from 0.1 to 1 m/day due to heterogeneous soil characteristics and variability in recharge water quality. A treatment upgrade to include sand filtration and UV disinfection (in 2013 prior to recharge improved the average infiltration rate per basin by 40% to 100%.

  16. Prediction of snowmelt infiltration into frozen soils

    International Nuclear Information System (INIS)

    Tao, Y.X.; Gray, D.M.

    1994-01-01

    A numerical model is presented, based on the local volume averaging formulation of transport phenomena in porous media, for simulating meltwater infiltration into unsaturated, frozen soil. With the defined flow and freezing boundary conditions at the snow-soil interface, using the concept of a surface local averaging volume, the time variation in profiles of temperature, liquid/ice content, infiltration/percolation rates, and rate of phase change in upper soil layers are predicted. In addition to a parametric analysis, model estimates of infiltration are compared with quantities calculated from field measurements of soil moisture changes and temperature during snow cover ablation, showing a reasonable agreement

  17. Sequestration of Sr-90 Subsurface Contamination in the Hanford 100-N Area by Surface Infiltration of a Ca-Citrate-Phosphate Solution

    Energy Technology Data Exchange (ETDEWEB)

    Szecsody, James E.; Rockhold, Mark L.; Oostrom, Martinus; Moore, R. C.; Burns, Carolyn A.; Williams, Mark D.; Zhong, Lirong; Fruchter, Jonathan S.; McKinley, James P.; Vermeul, Vincent R.; Covert, Matthew A.; Wietsma, Thomas W.; Breshears, Andrew T.; Garcia, Ben J.

    2009-03-01

    The objective of this project is to develop a method to emplace apatite precipitate in the 100N vadose zone, which results in sorption and ultimately incorporation of Sr-90 into the apatite structure. The Ca-citrate-PO4 solution can be infiltrated into unsaturated sediments to result in apatite precipitate to provide effective treatment of Sr-90 contamination. Microbial redistribution during solution infiltration and a high rate of citrate biodegradation for river water microbes (water used for solution infiltration) results in a relatively even spatial distribution of the citrate biodegradation rate and ultimately apatite precipitate in the sediment. Manipulation of the Ca-citrate-PO4 solution infiltration strategy can be used to result in apatite precipitate in the lower half of the vadose zone (where most of the Sr-90 is located) and within low-K layers (which are hypothesized to have higher Sr-90 concentrations). The most effective infiltration strategy to precipitate apatite at depth (and with sufficient lateral spread) was to infiltrate a high concentration solution (6 mM Ca, 15 mM citrate, 60 mM PO4) at a rapid rate (near ponded conditions), followed by rapid, then slow water infiltration. Repeated infiltration events, with sufficient time between events to allow water drainage in the sediment profile can be used to buildup the mass of apatite precipitate at greater depth. Low-K heterogeneities were effectively treated, as the higher residual water content maintained in these zones resulted in higher apatite precipitate concentration. High-K zones did not receive sufficient treatment by infiltration, although an alternative strategy of air/surfactant (foam) was demonstrated effective for targeting high-K zones. The flow rate manipulation used in this study to treat specific depths and heterogeneities are not as easy to implement at field scale due to the lack of characterization of heterogeneities and difficulty tracking the wetting front over a large

  18. Controls on the variability of net infiltration to desert sandstone

    Science.gov (United States)

    Heilweil, Victor M.; McKinney, Tim S.; Zhdanov, Michael S.; Watt, Dennis E.

    2007-01-01

    As populations grow in arid climates and desert bedrock aquifers are increasingly targeted for future development, understanding and quantifying the spatial variability of net infiltration becomes critically important for accurately inventorying water resources and mapping contamination vulnerability. This paper presents a conceptual model of net infiltration to desert sandstone and then develops an empirical equation for its spatial quantification at the watershed scale using linear least squares inversion methods for evaluating controlling parameters (independent variables) based on estimated net infiltration rates (dependent variables). Net infiltration rates used for this regression analysis were calculated from environmental tracers in boreholes and more than 3000 linear meters of vadose zone excavations in an upland basin in southwestern Utah underlain by Navajo sandstone. Soil coarseness, distance to upgradient outcrop, and topographic slope were shown to be the primary physical parameters controlling the spatial variability of net infiltration. Although the method should be transferable to other desert sandstone settings for determining the relative spatial distribution of net infiltration, further study is needed to evaluate the effects of other potential parameters such as slope aspect, outcrop parameters, and climate on absolute net infiltration rates.

  19. Specifics of Building Envelope Air Leakage Problems and Airtightness Measurements

    Directory of Open Access Journals (Sweden)

    Borodinecs Anatolijs

    2016-01-01

    Full Text Available In addition to transmission heat loses the infiltration of outdoor air can cause significant heat losses. The external building envelope should be airtight in order to prevent uncontrolled cold air infiltration. The article analysis modern building materials and structures influence on airtightness. The practical measurements of renovated buildings’ airtightness are presented and compared to non-renovated buildings. In addition paper presents data on airtightness measurements of whole multi apartment building and single apartment in analyzed building taking inco accout properties of building materials. The airtightness of single apartment was evaluated with support pressure in neighbor apartments. The results show that the airtightness measurements of multi apartment building can be evaluated by measuring single apartment on last floor with support pressure in neighbor apartments. The practical measurement of renovated buildings had shown the air leakage rate q50 of typical Latvian construction after renovation is between 2.5 and 2.9 m3/(m2·h. Since the building envelope has to minimize the heat loses (transmission and infiltration and ventilation system either mechanical or natural has to provide necessary air exchange, the building envelope airtightness shouldn’t be dependent on type of ventilation systems.

  20. Relative contributions of transient and steady state infiltration during ephemeral streamflow

    Science.gov (United States)

    Blasch, Kyle W.; Ferré, Ty P.A.; Hoffmann, John P.; Fleming, John B.

    2006-01-01

    Simulations of infiltration during three ephemeral streamflow events in a coarse‐grained alluvial channel overlying a less permeable basin‐fill layer were conducted to determine the relative contribution of transient infiltration at the onset of streamflow to cumulative infiltration for the event. Water content, temperature, and piezometric measurements from 2.5‐m vertical profiles within the alluvial sediments were used to constrain a variably saturated water flow and heat transport model. Simulated and measured transient infiltration rates at the onset of streamflow were about two to three orders of magnitude greater than steady state infiltration rates. The duration of simulated transient infiltration ranged from 1.8 to 20 hours, compared with steady state flow periods of 231 to 307 hours. Cumulative infiltration during the transient period represented 10 to 26% of the total cumulative infiltration, with an average contribution of approximately 18%. Cumulative infiltration error for the simulated streamflow events ranged from 9 to 25%. Cumulative infiltration error for typical streamflow events of about 8 hours in duration in is about 90%. This analysis indicates that when estimating total cumulative infiltration in coarse‐grained ephemeral stream channels, consideration of the transient infiltration at the onset of streamflow will improve predictions of the total volume of infiltration that may become groundwater recharge.

  1. Sensitivity of long-term bare soil infiltration simulations to hydraulic properties in an arid environment

    International Nuclear Information System (INIS)

    Stothoff, S.A.

    1997-01-01

    The suitability of Yucca Mountain, Nevada, for emplacement of a high-level nuclear waste geologic repository is currently being evaluated. Assessments of the repository performance suggest that the uncertainty in infiltration rates strongly affects predicted repository performance. Most of the ground surface over the potential repository footprint is characterized by shallow to deep colluvium/alluvium overlying densely fractured, welded tuffs. In order to identify characteristic behavior of infiltration that might be expected at the site, two idealizations of this situation are examined: an effectively semi-infinite column of alluvium and a two-layer column of alluvium over a fractured impermeable matrix. For each idealization the impact of hydraulic properties is assessed. Examining the sensitivity of bare soil simulator predictions for an effectively semi-infinite column, it is found that decreasing the air entry pressure while holding all other parameters at a fixed level tends to increase both the long-term average moisture content and the long-term average net infiltration flux for homogeneous media. In contrast, increasing the van Genuchten scale parameter (m = 1 - 1/n) or decreasing the porosity tends to decrease the average soil moisture but increase the infiltration. Most interestingly, three regimes are found for permeability. For relatively high permeabilities, there is a trend toward increasing average infiltration and increasing average moisture content with decreasing permeability. For relatively low permeabilities, vapor transport dominates over liquid transport, runoff and evaporation overwhelm infiltration, and the soil becomes very dry with essentially no infiltration flux Between the extreme cases of high and low permeability, there is a zone where decreasing permeability results in decreased infiltration but increased moisture content

  2. Climatic Forecasting of Net Infiltration at Yucca Mountain Using Analogue Meteorological Data

    International Nuclear Information System (INIS)

    B. Faybishenko

    2006-01-01

    At Yucca Mountain, Nevada, future changes in climatic conditions will most likely alter net infiltration, or the drainage below the bottom of the evapotranspiration zone within the soil profile or flow across the interface between soil and the densely welded part of the Tiva Canyon Tuff. The objectives of this paper are to: (a) develop a semi-empirical model and forecast average net infiltration rates, using the limited meteorological data from analogue meteorological stations, for interglacial (present day), and future monsoon, glacial transition, and glacial climates over the Yucca Mountain region, and (b) corroborate the computed net-infiltration rates by comparing them with the empirically and numerically determined groundwater recharge and percolation rates through the unsaturated zone from published data. In this paper, the author presents an approach for calculations of net infiltration, aridity, and precipitation-effectiveness indices, using a modified Budyko's water-balance model, with reference-surface potential evapotranspiration determined from the radiation-based Penman (1948) formula. Results of calculations show that net infiltration rates are expected to generally increase from the present-day climate to monsoon climate, to glacial transition climate, and then to the glacial climate. The forecasting results indicate the overlap between the ranges of net infiltration for different climates. For example, the mean glacial net-infiltration rate corresponds to the upper-bound glacial transition net infiltration, and the lower-bound glacial net infiltration corresponds to the glacial transition mean net infiltration. Forecasting of net infiltration for different climate states is subject to numerous uncertainties-associated with selecting climate analogue sites, using relatively short analogue meteorological records, neglecting the effects of vegetation and surface runoff and runon on a local scale, as well as possible anthropogenic climate changes

  3. Calibration and validation of a general infiltration model

    Science.gov (United States)

    Mishra, Surendra Kumar; Ranjan Kumar, Shashi; Singh, Vijay P.

    1999-08-01

    A general infiltration model proposed by Singh and Yu (1990) was calibrated and validated using a split sampling approach for 191 sets of infiltration data observed in the states of Minnesota and Georgia in the USA. Of the five model parameters, fc (the final infiltration rate), So (the available storage space) and exponent n were found to be more predictable than the other two parameters: m (exponent) and a (proportionality factor). A critical examination of the general model revealed that it is related to the Soil Conservation Service (1956) curve number (SCS-CN) method and its parameter So is equivalent to the potential maximum retention of the SCS-CN method and is, in turn, found to be a function of soil sorptivity and hydraulic conductivity. The general model was found to describe infiltration rate with time varying curve number.

  4. A review of air exchange rate models for air pollution exposure assessments.

    Science.gov (United States)

    Breen, Michael S; Schultz, Bradley D; Sohn, Michael D; Long, Thomas; Langstaff, John; Williams, Ronald; Isaacs, Kristin; Meng, Qing Yu; Stallings, Casson; Smith, Luther

    2014-11-01

    A critical aspect of air pollution exposure assessments is estimation of the air exchange rate (AER) for various buildings where people spend their time. The AER, which is the rate of exchange of indoor air with outdoor air, is an important determinant for entry of outdoor air pollutants and for removal of indoor-emitted air pollutants. This paper presents an overview and critical analysis of the scientific literature on empirical and physically based AER models for residential and commercial buildings; the models highlighted here are feasible for exposure assessments as extensive inputs are not required. Models are included for the three types of airflows that can occur across building envelopes: leakage, natural ventilation, and mechanical ventilation. Guidance is provided to select the preferable AER model based on available data, desired temporal resolution, types of airflows, and types of buildings included in the exposure assessment. For exposure assessments with some limited building leakage or AER measurements, strategies are described to reduce AER model uncertainty. This review will facilitate the selection of AER models in support of air pollution exposure assessments.

  5. A simplified model of soakaway infiltration interaction with a shallow groundwater table

    DEFF Research Database (Denmark)

    Roldin, Maria; Locatelli, Luca; Mark, Ole

    2013-01-01

    This paper presents a new and simplified modeling concept for soakaway infiltration in the presence of a shallow groundwater table, including representation of the local groundwater mound and its effects on the infiltration rate. The soil moisture retention curve is used to represent the influence......, and its effects on the infiltration rate, can be represented even if the spatial resolution of the groundwater flow model is coarser than the extent of the mound. The new model has been run for a number of scenarios and soil parameters, and the results compared to the output from a two...... of the mound on infiltration rates. The model is intended to be used in situations when distributed urban drainage models with soakaways or similar infiltration devices are coupled to distributed groundwater flow models. With this new modeling concept, the local mounding from small-scale infiltration systems...

  6. Relationship between indoor radon concentrations and air exchange rate

    International Nuclear Information System (INIS)

    Wang Jingshu; Liu Yuyu; Yao Xiaohua; Meng Jianfeng; Zhang Yongyi; Wang Xiaohe; Yu Xiufen.

    1995-01-01

    The indoor concentration of radon and the air exchange rate were simultaneously measured in four empty rooms, made of brick and cement, which were located in different floors of dwelling houses in Taiyuan, Shanxi, China. SF 6 tracer gas decay method was used to measure the air exchange rate. Indoor radon was collected with the dimembrane method. When the ventilation rate increased, the concentration of radon dropped rapidly. Regression analysis indicated that the indoor concentration of radon was equal to the outdoor level of radon when the air exchange rate was greater than 3-4. SF 6 decay method was an effective and convenient method for measuring the air exchange rate. There was no marked difference in measurements obtained in different locations of a room. (N.K.)

  7. Variably-saturated groundwater modeling for optimizing managed aquifer recharge using trench infiltration

    Science.gov (United States)

    Heilweil, Victor M.; Benoit, Jerome; Healy, Richard W.

    2015-01-01

    Spreading-basin methods have resulted in more than 130 million cubic meters of recharge to the unconfined Navajo Sandstone of southern Utah in the past decade, but infiltration rates have slowed in recent years because of reduced hydraulic gradients and clogging. Trench infiltration is a promising alternative technique for increasing recharge and minimizing evaporation. This paper uses a variably saturated flow model to further investigate the relative importance of the following variables on rates of trench infiltration to unconfined aquifers: saturated hydraulic conductivity, trench spacing and dimensions, initial water-table depth, alternate wet/dry periods, and number of parallel trenches. Modeling results showed (1) increased infiltration with higher hydraulic conductivity, deeper initial water tables, and larger spacing between parallel trenches, (2) deeper or wider trenches do not substantially increase infiltration, (3) alternating wet/dry periods result in less overall infiltration than keeping the trenches continuously full, and (4) larger numbers of parallel trenches within a fixed area increases infiltration but with a diminishing effect as trench spacing becomes tighter. An empirical equation for estimating expected trench infiltration rates as a function of hydraulic conductivity and initial water-table depth was derived and can be used for evaluating feasibility of trench infiltration in other hydrogeologic settings

  8. Analysis of rainfall infiltration law in unsaturated soil slope.

    Science.gov (United States)

    Zhang, Gui-rong; Qian, Ya-jun; Wang, Zhang-chun; Zhao, Bo

    2014-01-01

    In the study of unsaturated soil slope stability under rainfall infiltration, it is worth continuing to explore how much rainfall infiltrates into the slope in a rain process, and the amount of rainfall infiltrating into slope is the important factor influencing the stability. Therefore, rainfall infiltration capacity is an important issue of unsaturated seepage analysis for slope. On the basis of previous studies, rainfall infiltration law of unsaturated soil slope is analyzed. Considering the characteristics of slope and rainfall, the key factors affecting rainfall infiltration of slope, including hydraulic properties, water storage capacity (θs - θr), soil types, rainfall intensities, and antecedent and subsequent infiltration rates on unsaturated soil slope, are discussed by using theory analysis and numerical simulation technology. Based on critical factors changing, this paper presents three calculation models of rainfall infiltrability for unsaturated slope, including (1) infiltration model considering rainfall intensity; (2) effective rainfall model considering antecedent rainfall; (3) infiltration model considering comprehensive factors. Based on the technology of system response, the relationship of rainfall and infiltration is described, and the prototype of regression model of rainfall infiltration is given, in order to determine the amount of rain penetration during a rain process.

  9. Assessment of infiltration heat recovery and its impact on energy consumption for residential buildings

    International Nuclear Information System (INIS)

    Solupe, Mikel; Krarti, Moncef

    2014-01-01

    Highlights: • Five steady-state air infiltration heat recovery or IHR models are described and compared. • IHR models are incorporated within whole-building simulation analysis tool. • IHR can reduce the thermal loads of residential buildings by 5–30%. - Abstract: Infiltration is a major contributor to the energy consumption of buildings, particularly in homes where it accounts for one-third of the heating and cooling loads. Traditionally, infiltration is calculated independent of the building envelope performance, however, it has been established that a thermal coupling exists between the infiltration and conduction heat transfer of the building envelope. This effect is known as infiltration heat recovery (IHR). Experiments have shown that infiltration heat recovery can typically reduce the infiltration thermal load by 10–20%. Currently, whole-building energy simulation tools do not account for the effect of infiltration heat recovery on heating and cooling loads. In this paper, five steady-state IHR models are described to account for the thermal interaction between infiltration air and building envelope components. In particular, inter-model and experimental comparisons are carried out to assess the prediction accuracy of five IHR models. In addition, the results from a series of sensitivity analyses are presented, including an evaluation of the predictions for heating energy use associated with four audited homes obtained from whole-building energy simulation analysis with implemented infiltration heat recovery models. Experimental comparison of the IHR models reveal that the predictions from all the five models are consistent and are within 2% when 1-D flow and heat transfer conditions are considered. When implementing IHR models to a whole-building simulation environment, a reduction of 5–30% in heating consumption is found for four audited residential homes

  10. Soil infiltration characteristics in the Tarim River floodplain

    Science.gov (United States)

    Overflow from rivers play an important role for ecological conservation in Tarim Basin, however, there was limited information on infiltration from overflow of the Tarim River. The objective of this study was to investigate steady infiltration rate for three types of land use (forest, shrub and bare...

  11. On-site infiltration of road runoff using pervious pavements with subjacent infiltration trenches as source control strategy.

    Science.gov (United States)

    Fach, S; Dierkes, C

    2011-01-01

    The focus in this work was on subsoil infiltration of stormwater from parking lots. With regard to operation, reduced infiltration performance due to clogging and pollutants in seepage, which may contribute to contaminate groundwater, are of interest. The experimental investigation covered a pervious pavement with a subjacent infiltration trench draining an impervious area of 2 ha. In order to consider seasonal effects on the infiltration performance, the hydraulic conductivity was measured tri-monthly during monitoring with a mobile sprinkling unit. To assess natural deposits jointing, road bed, gravel of infiltration trenches and subsoil were analysed prior to commencement of monitoring for heavy metals, polycyclic aromatic and mineral oil type hydrocarbons. Furthermore, from 22 storm events, water samples of rainfall, surface runoff, seepage and ground water were analysed with regard to the above mentioned pollutants. The study showed that the material used for the joints had a major impact on the initial as well as the final infiltration rates. Due to its poor hydraulic conductivity, limestone gravel should not be used as jointing. Furthermore, it is recommended that materials for the infiltration facilities are ensured free of any contaminants prior to construction. Polycyclic aromatic and mineral oil type hydrocarbons were, with the exception of surface runoff, below detection limits. Heavy metal concentrations of groundwater were with the exception of lead (because of high background concentrations), below the permissible limits.

  12. Control in indoor radon decay products by air treatment devices

    International Nuclear Information System (INIS)

    Hinds, W.C.; Rudnick, S.N.; Maher, E.F.; First, M.W.

    1983-01-01

    An evaluation of the efficacy of household air cleaning devices as a means to control radon decay products in existing buildings is presented. Previous research on air cleaning methods for airborne radon decay products has been directed primarily to the control of radon decay products in mines and has only limited application to control in residences where dust concentration, air change rate, and humidity are lower than in mines. Results show that room size air cleaners can achieve substantial reductions in working levels in residences. Reductions observed at air infiltration rates of 0.52 air changes per hour ranged from 58 to 89%. Although the two air cleaners tested produced the greatest reductions, the low cost, simplicity, and other benefits of air circulating fans, particularly the ceiling fan, appear to make them most suitable for residences

  13. Net-infiltration map of the Navajo Sandstone outcrop area in western Washington County, Utah

    Science.gov (United States)

    Heilweil, Victor M.; McKinney, Tim S.

    2007-01-01

    As populations grow in the arid southwestern United States and desert bedrock aquifers are increasingly targeted for future development, understanding and quantifying the spatial variability of net infiltration and recharge becomes critically important for inventorying groundwater resources and mapping contamination vulnerability. A Geographic Information System (GIS)-based model utilizing readily available soils, topographic, precipitation, and outcrop data has been developed for predicting net infiltration to exposed and soil-covered areas of the Navajo Sandstone outcrop of southwestern Utah. The Navajo Sandstone is an important regional bedrock aquifer. The GIS model determines the net-infiltration percentage of precipitation by using an empirical equation. This relation is derived from least squares linear regression between three surficial parameters (soil coarseness, topographic slope, and downgradient distance from outcrop) and the percentage of estimated net infiltration based on environmental tracer data from excavations and boreholes at Sand Hollow Reservoir in the southeastern part of the study area.Processed GIS raster layers are applied as parameters in the empirical equation for determining net infiltration for soil-covered areas as a percentage of precipitation. This net-infiltration percentage is multiplied by average annual Parameter-elevation Regressions on Independent Slopes Model (PRISM) precipitation data to obtain an infiltration rate for each model cell. Additionally, net infiltration on exposed outcrop areas is set to 10 percent of precipitation on the basis of borehole net-infiltration estimates. Soils and outcrop net-infiltration rates are merged to form a final map.Areas of low, medium, and high potential for ground-water recharge have been identified, and estimates of net infiltration range from 0.1 to 66 millimeters per year (mm/yr). Estimated net-infiltration rates of less than 10 mm/yr are considered low, rates of 10 to 50 mm/yr are

  14. Comparison of infiltration capacity of permanent grassland and arable land during the 2011 growing season

    OpenAIRE

    Tomáš Mašíček; F. Toman; M. Vičanová

    2012-01-01

    The aim of this paper was to compare the rate of infiltration and cumulative infiltration in permanent grassland (PG) and in arable land over the course of the 2011 growing season. The measurement of water infiltration into soil was conducted via ponded infiltration method based on the use of two concentric cylinders in field conditions. Kostiakov equations were applied to evaluate the ponded infiltration. Based on field measurements, the dependence of infiltration rate (v) on time (t) was de...

  15. [Infiltration characteristics of soil water on loess slope land under intermittent and repetitive rainfall conditions].

    Science.gov (United States)

    Li, Yi; Shao, Ming-An

    2008-07-01

    Based on the experiments of controlled intermittent and repetitive rainfall on slope land, the infiltration and distribution characteristics of soil water on loess slope land were studied. The results showed that under the condition of intermittent rainfall, the cumulative runoff during two rainfall events increased linearly with time, and the wetting front also increased with time. In the interval of the two rainfall events, the wetting front increased slowly, and the infiltration rate was smaller on steeper slope than on flat surface. During the second rainfall event, there was an obvious decreasing trend of infiltration rate with time. The cumulative infiltration on 15 degrees slope land was larger than that of 25 degrees slope land, being 178 mm and 88 mm, respectively. Under the condition of repetitive rainfall, the initial infiltration rate during each rainfall event was relatively large, and during the first rainfall, both the infiltration rate and the cumulative infiltration at various stages were larger than those during the other three rainfall events. However, after the first rainfall, there were no obvious differences in the infiltration rate among the next three rainfall events. The more the rainfall event, the deeper the wetting front advanced.

  16. Transient Point Infiltration In The Unsaturated Zone

    Science.gov (United States)

    Buecker-Gittel, M.; Mohrlok, U.

    The risk assessment of leaking sewer pipes gets more and more important due to urban groundwater management and environmental as well as health safety. This requires the quantification and balancing of transport and transformation processes based on the water flow in the unsaturated zone. The water flow from a single sewer leakage could be described as a point infiltration with time varying hydraulic conditions externally and internally. External variations are caused by the discharge in the sewer pipe as well as the state of the leakage itself. Internal variations are the results of microbiological clogging effects associated with the transformation processes. Technical as well as small scale laboratory experiments were conducted in order to investigate the water transport from an transient point infiltration. From the technical scale experiment there was evidence that the water flow takes place under transient conditions when sewage infiltrates into an unsaturated soil. Whereas the small scale experiments investigated the hydraulics of the water transport and the associated so- lute and particle transport in unsaturated soils in detail. The small scale experiment was a two-dimensional representation of such a point infiltration source where the distributed water transport could be measured by several tensiometers in the soil as well as by a selective measurement of the discharge at the bottom of the experimental setup. Several series of experiments were conducted varying the boundary and initial con- ditions in order to derive the important parameters controlling the infiltration of pure water from the point source. The results showed that there is a significant difference between the infiltration rate in the point source and the discharge rate at the bottom, that could be explained by storage processes due to an outflow resistance at the bottom. This effect is overlayn by a decreasing water content decreases over time correlated with a decreasing infiltration

  17. Estimation of uncertainty in tracer gas measurement of air change rates.

    Science.gov (United States)

    Iizuka, Atsushi; Okuizumi, Yumiko; Yanagisawa, Yukio

    2010-12-01

    Simple and economical measurement of air change rates can be achieved with a passive-type tracer gas doser and sampler. However, this is made more complex by the fact many buildings are not a single fully mixed zone. This means many measurements are required to obtain information on ventilation conditions. In this study, we evaluated the uncertainty of tracer gas measurement of air change rate in n completely mixed zones. A single measurement with one tracer gas could be used to simply estimate the air change rate when n = 2. Accurate air change rates could not be obtained for n ≥ 2 due to a lack of information. However, the proposed method can be used to estimate an air change rate with an accuracy of air change rate can be avoided. The proposed estimation method will be useful in practical ventilation measurements.

  18. Effects of thinning intensities on soil infiltration and water storage capacity in a Chinese pine-oak mixed forest.

    Science.gov (United States)

    Chen, Lili; Yuan, Zhiyou; Shao, Hongbo; Wang, Dexiang; Mu, Xingmin

    2014-01-01

    Thinning is a crucial practice in the forest ecosystem management. The soil infiltration rate and water storage capacity of pine-oak mixed forest under three different thinning intensity treatments (15%, 30%, and 60%) were studied in Qinling Mountains of China. The thinning operations had a significant influence on soil infiltration rate and water storage capacity. The soil infiltration rate and water storage capacity in different thinning treatments followed the order of control (nonthinning): soil infiltration rate and water storage capacity of pine-oak mixed forest in Qinling Mountains. The soil initial infiltration rate, stable infiltration rate, and average infiltration rate in thinning 30% treatment were significantly increased by 21.1%, 104.6%, and 60.9%, compared with the control. The soil maximal water storage capacity and noncapillary water storage capacity in thinning 30% treatment were significantly improved by 20.1% and 34.3% in contrast to the control. The soil infiltration rate and water storage capacity were significantly higher in the surface layer (0~20 cm) than in the deep layers (20~40 cm and 40~60 cm). We found that the soil property was closely related to soil infiltration rate and water storage capacity.

  19. A rapid screening-level method to optimize location of infiltration ponds.

    Science.gov (United States)

    Fennemore, G G; Davis, A; Goss, L; Warrick, A W

    2001-01-01

    A rapid-screening technique was developed to identify lithologies that best disperse artificial recharge via surface infiltration and minimize effects on ground water chemistry. The technique prospectively evaluates basin infiltration rates and water chemistry influences by integrating geotechnical, hydraulic, and water quality data with column test data and numerical modeling. The technique was validated using field data collected from surface infiltration basins designed to recharge ground water pumped from the Pipeline pit gold mine in Nevada. Observed recharge rates at these infiltration sites correlated most significantly with depth to groundwater, with basins in coarse-grained lithologies performing better (0.45 to 0.85 m/day) than those with fine-grained layers ( 2000 mg/L) than coarse-grained soils (infiltration basins for a variety of lithologies. Sites for infiltration basins can be rapidly screened to include areas with greatest depth to groundwater and in coarsest alluvial sediments, and impact to ground water chemistry can be reliably predicted using computer modeling and column test results.

  20. Areal variation and chemical modification of weathered shale infiltration characteristics

    International Nuclear Information System (INIS)

    Luxmoore, R.J.; Spalding, B.P.; Munro, I.M.

    1981-01-01

    Spatial variability of infiltration into a weathered shale subsoil was evaluated at a site proximal to one used for shallow land burial of low-level radioactive waste at Oak Ridge National Laboratory. Double-ring infiltometers were installed at 48 locations on a 2- by 2-m grid after the removal of 1 to 2 m of soil (Litz-Sequoia association, Typic Hapludults). Infiltration rates were measured before and during the 0- to 20- and 239- to 259-day periods following treatment with solutions of NaOH, KOH, NaF, NaAlO 2 , and Na 2 SiO 3 at rates of 151 equivalents/m 2 . None of these chemical treatments significantly altered infiltration rate, indicating that chemical modification of soil exchange properties may be achieved without inducing hydrologic disturbance in these subsoils. A semivariogram analysis of infiltration data showed that areal variability was random; any spatial patterning must therefore occur at a smaller scale than 2 m

  1. Climatic Forecasting of Net Infiltration at Yucca Mountain Using Analogue Meteorological Data

    International Nuclear Information System (INIS)

    Faybishenko, Boris

    2005-01-01

    At Yucca Mountain, NV, future changes in climatic conditions will probably alter net infiltration, drainage below the bottom of the evapotranspiration zone within the soil profile, or flow across the interface between soil and the densely welded part of the Tiva Canyon Tuff. The objectives of this study were to: (1) develop a semiempirical model and forecast average net infiltration rates, using the limited meteorological data from analog meteorological stations, for interglacial(present day), and future monsoon, glacial transition, and glacial climates over the Yucca Mountain region; and (2) corroborate the computed net infiltration rates by comparing them with the empirically and numerically determined groundwater recharge and percolation rates through the unsaturated zone from published data. This study approached calculations of net infiltration, aridity, and precipitation effectiveness indices using a modified Budyko's water-balance model, with reference-surface potential evapotranspiration determined from the radiation-based Penman formula. Results of calculations show that net infiltration rates are expected to generally increase from the present-day climate to monsoon climate, to glacial transition climate, and then to the glacial climate, following a power law relationship between net infiltration and precipitation. The forecasting results indicate the overlap between the ranges of net infiltration for different climates. Forecasting of net infiltration for different climate states is subject to numerous uncertainties associated with selecting climate analog sites, using relatively short analog meteorological records, neglecting the effects of vegetation and surface runoff and run-on on a local scale, as well as possible anthropogenically induced climate changes

  2. Prototype Systems for Measuring Outdoor Air Intake Rates in Rooftop Air Handlers

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chan, Wanyu R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hotchi, Toshifumi [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-01-01

    The widespread absence of systems for real-time measurement and feedback control, of minimum outdoor air intake rates in HVAC systems contributes to the poor control of ventilation rates in commercial buildings. Ventilation rates affect building energy consumption and influence occupant health. The project designed fabricated and tested four prototypes of systems for measuring rates of outdoor air intake into roof top air handlers. All prototypes met the ±20% accuracy target at low wind speeds, with all prototypes accurate within approximately ±10% after application of calibration equations. One prototype met the accuracy target without a calibration. With two of four prototype measurement systems, there was no evidence that wind speed or direction affected accuracy; however, winds speeds were generally below usually 3.5 m s-1 (12.6 km h-1) and further testing is desirable. The airflow resistance of the prototypes was generally less than 35 Pa at maximum RTU air flow rates. A pressure drop of this magnitude will increase fan energy consumption by approximately 4%. The project did not have resources necessary to estimate costs of mass produced systems. The retail cost of components and materials used to construct prototypes ranged from approximately $1,200 to $1,700. The test data indicate that the basic designs developed in this project, particularly the designs of two of the prototypes, have considerable merit. Further design refinement, testing, and cost analysis would be necessary to fully assess commercial potential. The designs and test results will be communicated to the HVAC manufacturing community.

  3. (18)F-FDG dynamic PET/CT in patients with multiple myeloma: patterns of tracer uptake and correlation with bone marrow plasma cell infiltration rate.

    Science.gov (United States)

    Sachpekidis, Christos; Mai, Elias K; Goldschmidt, Hartmut; Hillengass, Jens; Hose, Dirk; Pan, Leyun; Haberkorn, Uwe; Dimitrakopoulou-Strauss, Antonia

    2015-06-01

    The value of F-FDG PET in the diagnostic approach of multiple myeloma (MM) remains incompletely elicited. Little is known about the kinetics of F-FDG in the bone marrow and extramedullary sites in MM. This study aimed to evaluate quantitative data on kinetics and distribution patterns of F-FDG in MM patients with regard to pelvic bone marrow plasma cell infiltration. The study included 40 patients with primary MM. Dynamic PET/CT scanning of the lower lumbar spine and pelvis was performed after the administration of F-FDG. Whole-body PET/CT studies were performed. Sites of focal increased tracer uptake were considered as highly suggestive of myelomatous involvement after taking into account the patient history and CT findings. Bone marrow of the os ilium without pathologic tracer accumulation served as reference. The evaluation of dynamic PET/CT studies was based in addition to the conventional visual (qualitative) assessment, on semiquantitative (SUV) calculations, as well as on absolute quantitative estimations after application of a 2-tissue compartment model and a noncompartmental approach. F-FDG quantitative information and corresponding distribution patterns were correlated with pelvic bone marrow plasma cell infiltration. Fifty-two myelomatous lesions were detected in the pelvis. All parameters in suspected MM lesions ranged in significantly higher levels than in reference tissue (P PET/CT imaging demonstrated 4 patterns of tracer uptake; these are as follows: negative, focal, diffuse, and mixed (focal/diffuse) tracer uptake. Patients with a mixed pattern of radiotracer uptake had the highest mean plasma cell infiltration rate in their bone marrow, whereas those with negative PET/CT scans demonstrated the lowest bone marrow plasma cell infiltration. In total, 265 focal myeloma-indicative F-FDG-avid lesions were detected, 129 of which correlated with low-dose CT osteolytic findings. No significant correlation between the number of focal lesions detected in PET

  4. Position paper -- Tank ventilation system design air flow rates

    International Nuclear Information System (INIS)

    Goolsby, G.K.

    1995-01-01

    The purpose of this paper is to document a project position on required ventilation system design air flow rates for the waste storage tanks currently being designed by project W-236A, the Multi-Function Waste Tank Facility (MWTF). The Title 1 design primary tank heat removal system consists of two systems: a primary tank vapor space ventilation system; and an annulus ventilation system. At the conclusion of Title 1 design, air flow rates for the primary and annulus ventilation systems were 960 scfm and 4,400 scfm, respectively, per tank. These design flow rates were capable of removing 1,250,000 Btu/hr from each tank. However, recently completed and ongoing studies have resulted in a design change to reduce the extreme case heat load to 700,000 Btu/hr. This revision of the extreme case heat load, coupled with results of scale model evaporative testing performed by WHC Thermal Hydraulics, allow for a reduction of the design air flow rates for both primary and annulus ventilation systems. Based on the preceding discussion, ICF Kaiser Hanford Co. concludes that the design should incorporate the following design air flow rates: Primary ventilation system--500 scfm maximum and Annulus ventilation system--1,100 scfm maximum. In addition, the minimum air flow rates in the primary and annulus ventilation systems will be investigated during Title 2 design. The results of the Title 2 investigation will determine the range of available temperature control using variable air flows to both ventilation systems

  5. Infiltration SuDS Map

    OpenAIRE

    Dearden, Rachel

    2012-01-01

    Infiltration SuDS are sustainable drainage systems (SuDS) that allow surface water to infiltrate to the ground. Examples include soakaways, infiltration basins, infiltration trenches and permeable pavements. Before planning to install Infiltration SuDS, the suitability of the ground should be assessed. The British Geological Survey has developed a bespoke Infiltration SuDS Map that enables a preliminary assessment of the suitability of the ground for infiltration SuDS. Th...

  6. [Soil infiltration capacity under different vegetations in southern Ningxia Loess hilly region].

    Science.gov (United States)

    Yang, Yong-Hui; Zhao, Shi-Wei; Lei, Ting-Wu; Liu, Han

    2008-05-01

    A new apparatus for measuring the run off-on-out under simulated rainfall conditions was used to study the soil infiltration capacity under different rainfall intensities and vegetations in loess hilly region of southern Ningxia, with the relationships between soil water-stable aggregate content and soil stable infiltration rate under different vegetations analyzed. The results showed that the regression equations between rainfall duration and soil infiltration rate under different vegetations all followed y = a + be(-cx), with R2 ranged from 0.9678 to 0.9969. With the increase of rainfall intensity, the soil stable infiltration rate on slope cropland decreased, while that on Medicago lupulina land, natural grassland, and Caragana korshinskii land increased. Under the rainfall intensity of 20 mm h(-1), the rainfall infiltration translation rate (RITR) was decreased in the order of M. lupulina land > slope cropland > natural grassland > C. korshinskii land; while under the rainfall intensity of 40 mm h(-1) and 56 mm h(-1), the RITR was in the sequence of M. lupulina land > natural grassland > slope cropland > C. korshinskii land, and decreased with increasing rainfall intensity. After the reversion of cropland to grassland and forest land, and with the increase of re-vegetation, the amount of >0.25 mm soil aggregates increased, and soil infiltration capacity improved. The revegetation in study area effectively improved soil structure and soil infiltration capacity, and enhanced the utilization potential of rainfall on slope.

  7. Infiltration on sloping terrain and its role on runoff generation and slope stability

    Science.gov (United States)

    Loáiciga, Hugo A.; Johnson, J. Michael

    2018-06-01

    A modified Green-and-Ampt model is formulated to quantify infiltration on sloping terrain underlain by homogeneous soil wetted by surficial water application. This paper's theory for quantifying infiltration relies on the mathematical statement of the coupled partial differential equations (pdes) governing infiltration and runoff. These pdes are solved by employing an explicit finite-difference numerical method that yields the infiltration, the infiltration rate, the depth to the wetting front, the rate of runoff, and the depth of runoff everywhere on the slope during external wetting. Data inputs consist of a water application rate or the rainfall hyetograph of a storm of arbitrary duration, soil hydraulic characteristics and antecedent moisture, and the slope's hydraulic and geometric characteristics. The presented theory predicts the effect an advancing wetting front has on slope stability with respect to translational sliding. This paper's theory also develops the 1D pde governing suspended sediment transport and slope degradation caused by runoff influenced by infiltration. Three examples illustrate the application of the developed theory to calculate infiltration and runoff on a slope and their role on the stability of cohesive and cohesionless soils forming sloping terrain.

  8. Field Test Evaluation of Conservation Retrofits of Low-Income, Single-Family Buildings in Wisconsin: Blower-Door-Directed Infiltration Reduction Procedure, Field Test Implementation and Results; TOPICAL

    International Nuclear Information System (INIS)

    Gettings, M.B.

    2001-01-01

    A blower-door-directed infiltration retrofit procedure was field tested on 18 homes in south central Wisconsin. The procedure, developed by the Wisconsin Energy Conservation Corporation, includes recommended retrofit techniques as well as criteria for estimating the amount of cost-effective work to be performed on a house. A recommended expenditure level and target air leakage reduction, in air changes per hour at 50 Pascal (ACH50), are determined from the initial leakage rate measured. The procedure produced an average 16% reduction in air leakage rate. For the 7 houses recommended for retrofit, 89% of the targeted reductions were accomplished with 76% of the recommended expenditures. The average cost of retrofits per house was reduced by a factor of four compared with previous programs. The average payback period for recommended retrofits was 4.4 years, based on predicted energy savings computed from achieved air leakage reductions. Although exceptions occurred, the procedure's 8 ACH50 minimum initial leakage rate for advising retrofits to be performed appeared a good choice, based on cost-effective air leakage reduction. Houses with initial rates of 7 ACH50 or below consistently required substantially higher costs to achieve significant air leakage reductions. No statistically significant average annual energy savings was detected as a result of the infiltration retrofits. Average measured savings were -27 therm per year, indicating an increase in energy use, with a 90% confidence interval of 36 therm. Measured savings for individual houses varied widely in both positive and negative directions, indicating that factors not considered affected the results. Large individual confidence intervals indicate a need to increase the accuracy of such measurements as well as understand the factors which may cause such disparity. Recommendations for the procedure include more extensive training of retrofit crews, checks for minimum air exchange rates to insure air quality

  9. Estimation of Uncertainty in Tracer Gas Measurement of Air Change Rates

    Directory of Open Access Journals (Sweden)

    Atsushi Iizuka

    2010-12-01

    Full Text Available Simple and economical measurement of air change rates can be achieved with a passive-type tracer gas doser and sampler. However, this is made more complex by the fact many buildings are not a single fully mixed zone. This means many measurements are required to obtain information on ventilation conditions. In this study, we evaluated the uncertainty of tracer gas measurement of air change rate in n completely mixed zones. A single measurement with one tracer gas could be used to simply estimate the air change rate when n = 2. Accurate air change rates could not be obtained for n ≥ 2 due to a lack of information. However, the proposed method can be used to estimate an air change rate with an accuracy of

  10. CLIMATIC FORECASTING OF NET INFILTRATION AT YUCCA MOUNTAIN, USING ANALOGUE METEOROLOGICAL DATA

    International Nuclear Information System (INIS)

    B. Faybishenko

    2005-01-01

    Net infiltration is a key hydrologic parameter that controls the rate of deep percolation through the unsaturated zone, the groundwater recharge, radionuclide transport, and seepage into the underground tunnels. Because net infiltration is largely affected by climatic conditions, future changes in climatic conditions will potentially alter net infiltration. The objectives of this presentation are to: (1) Present a conceptual model and a semi-empirical approach for regional, climatic forecasting of net infiltration, based on the precipitation and temperature data from analogue meteorological stations, and (2) Demonstrate the results of forecasting net infiltration for future climates--interglacial, monsoon and glacial--over the Yucca Mountain region for the period of 500,000 years. Calculations of the net infiltration were performed using a modified Budyko's water-balance model, for which potential evapotranspiration was evaluated from the temperature-based Thornthwaite formula. (Both Budyko's and Thornthwaite's formulae have been used broadly in hydrological studies.) The results of calculations were used for ranking net infiltration, along with the aridity and precipitation-effectiveness (P-E) indexes, for future climatic scenarios. Using this approach, we determined a general trend of increasing net infiltration from the present-day (interglacial) climate to monsoon, intermediate (glacial transition), and then to the glacial climate. Ranking of the aridity and P-E indexes is practically the same as that of net infiltration. The validation of the computed net infiltration rates yielded a good match with other field and modeling study results of groundwater recharge and net infiltration evaluation

  11. Spatial variability of steady-state infiltration into a two-layer soil system on burned hillslopes

    Science.gov (United States)

    Kinner, D.A.; Moody, J.A.

    2010-01-01

    Rainfall-runoff simulations were conducted to estimate the characteristics of the steady-state infiltration rate into 1-m2 north- and south-facing hillslope plots burned by a wildfire in October 2003. Soil profiles in the plots consisted of a two-layer system composed of an ash on top of sandy mineral soil. Multiple rainfall rates (18.4-51.2 mm h-1) were used during 14 short-duration (30 min) and 2 long-duration simulations (2-4 h). Steady state was reached in 7-26 min. Observed spatially-averaged steady-state infiltration rates ranged from 18.2 to 23.8 mm h-1 for north-facing and from 17.9 to 36.0 mm h-1 for south-facing plots. Three different theoretical spatial distribution models of steady-state infiltration rate were fit to the measurements of rainfall rate and steady-state discharge to provided estimates of the spatial average (19.2-22.2 mm h-1) and the coefficient of variation (0.11-0.40) of infiltration rates, overland flow contributing area (74-90% of the plot area), and infiltration threshold (19.0-26 mm h-1). Tensiometer measurements indicated a downward moving pressure wave and suggest that infiltration-excess overland flow is the runoff process on these burned hillslope with a two-layer system. Moreover, the results indicate that the ash layer is wettable, may restrict water flow into the underlying layer, and increase the infiltration threshold; whereas, the underlying mineral soil, though coarser, limits the infiltration rate. These results of the spatial variability of steady-state infiltration can be used to develop physically-based rainfall-runoff models for burned areas with a two-layer soil system. ?? 2010 Elsevier B.V.

  12. Determining the extent of groundwater interference on the performance of infiltration trenches

    DEFF Research Database (Denmark)

    Locatelli, Luca; Mark, Ole; Mikkelsen, Peter Steen

    2015-01-01

    Infiltration trenches are widely used in stormwater management, but their capacity decreases when installed in areas with shallow groundwater where infiltration is limited by groundwater drainage. Here the hydrological performance of single infiltration trenches in areas with shallow water tables...... is quantified in terms of their capability to reduce peak flow, peak volume and annual stormwater runoff volume. To simulate the long term hydrological performance of infiltration trenches two different models are employed. The models continuously simulate infiltration rates from infiltration trenches using...... to quantify the impact of parameter variability for each scenario. Statistical analysis of the continuous long term model simulations was used to quantify the hydrological performance of infiltration trenches. Results show that infiltration trenches are affected by groundwater when there is an unsaturated...

  13. Effects of sodium polyacrylate on water retention and infiltration capacity of a sandy soil

    OpenAIRE

    Zhuang, Wenhua; Li, Longguo; Liu, Chao

    2013-01-01

    Based on the laboratory study, the effects of sodium polyacrylate (SP) was investigated at 5 rates of 0, 0.08, 0.2, 0.5, and 1%, on water retention, saturated hydraulic conductivity(Ks), infiltration characteristic and water distribution profiles of a sandy soil. The results showed that water retention and available water capacity effectively increased with increasing SP rate. The Ks and the rate of wetting front advance and infiltration under certain pond infiltration was significantly reduc...

  14. Infiltration of SOFC Stacks: Evaluation of the Electrochemical Performance Enhancement and the Underlying Changes in the Microstructure

    DEFF Research Database (Denmark)

    Kiebach, Wolff-Ragnar; Zielke, Philipp; Høgh, Jens Valdemar Thorvald

    2016-01-01

    Experimental SOFC stacks with 10 SOFCs (LSM-YSZ/YSZ/Ni-YSZ) were infiltrated with CGO and Ni-CGO on the air and fuel side, respectively in an attempt to counter degradation and improve the output. The electrochemical performance of each cell was characterized (i) before infiltration, (ii) after i...

  15. Water erosion and soil water infiltration in different stages of corn development and tillage systems

    OpenAIRE

    Daniel F. de Carvalho; Eliete N. Eduardo; Wilk S. de Almeida; Lucas A. F. Santos; Teodorico Alves Sobrinho

    2015-01-01

    ABSTRACTThis study evaluated soil and water losses, soil water infiltration and infiltration rate models in soil tillage systems and corn (Zea mays, L.) development stages under simulated rainfall. The treatments were: cultivation along contour lines, cultivation down the slope and exposed soil. Soil losses and infiltration in each treatment were quantified for rains applied using a portable simulator, at 0, 30, 60 and 75 days after planting. Infiltration rates were estimated using the models...

  16. Indoor air-quality measurements in energy-efficient residential buildings

    Energy Technology Data Exchange (ETDEWEB)

    Berk, J.V.; Hollowell, C.D.; Pepper, J.H.; Young, R.

    1980-05-01

    The potential impact on indoor air quality of energy-conserving measures that reduce ventilation is being assessed in a field-monitoring program conducted by the Lawrence Berkeley Laboratory. Using a mobile laboratory, on-site monitoring of infiltration rate, carbon dioxide, carbon monoxide, nitrogen dioxide, nitric oxide, ozone, sulfur dioxide, formaldehyde, total aldehydes, and particulates was conducted in three houses designed to be energy-efficient. Preliminary results show that energy-conserving design features that reduce air-exchange rates compromise indoor air quality; specifically, indoor levels of several pollutants were found to exceed levels detected outdoors. Although the indoor levels of most pollutants are within limits established by present outdoor air-quality standards, considerable work remains to be accomplished before health-risk effects can be accurately assessed and broad-scale regulatory guidelines revised to comply with energy-conservation goals.

  17. Phlebitis and infiltration: vascular trauma associated with the peripheral venous catheter

    Science.gov (United States)

    Braga, Luciene Muniz; Parreira, Pedro Miguel; Oliveira, Anabela de Sousa Salgueiro; Mónico, Lisete dos Santos Mendes; Arreguy-Sena, Cristina; Henriques, Maria Adriana

    2018-01-01

    ABSTRACT Objective: to determine the incidence rate and risk factors for the nursing-sensitive indicators phlebitis and infiltration in patients with peripheral venous catheters (PVCs). Method: cohort study with 110 patients. Scales were used to assess and document phlebitis and infiltration. Socio-demographic variables, clinical variables related to the PVC, medication and hospitalization variables were collected. Descriptive and inferential analysis and multivariate logistic models were used. Results: the incidence rate of phlebitis and infiltration was respectively 43.2 and 59.7 per 1000 catheter-days. Most PVCs with these vascular traumas were removed in the first 24 hours. Risk factors for phlebitis were: length of hospital stay (p=0.042) and number of catheters inserted (p<0.001); risk factors for infiltration were: piperacillin/tazobactan (p=0.024) and the number of catheters inserted (p<0.001). Conclusion: the investigation documented the incidence of nursing-sensitive indicators (phlebitis and infiltration) and revealed new risk factors related to infiltration. It also allowed a reflection on the nursing care necessary to prevent these vascular traumas and on the indications and contraindications of the PVC, supporting the implementation of the PICC as an alternative to PVC. PMID:29791668

  18. Nutrient Release from Disturbance of Infiltration System Soils during Construction

    Directory of Open Access Journals (Sweden)

    Daniel P. Treese

    2012-01-01

    Full Text Available Subsurface infiltration and surface bioretention systems composed of engineered and/or native soils are preferred tools for stormwater management. However, the disturbance of native soils, especially during the process of adding amendments to improve infiltration rates and pollutant removal, may result in releases of nutrients in the early life of these systems. This project investigated the nutrient release from two soils, one disturbed and one undisturbed. The disturbed soil was collected intact, but had to be air-dried, and the columns repacked when soil shrinkage caused bypassing of water along the walls of the column. The undisturbed soil was collected and used intact, with no repacking. The disturbed soil showed elevated releases of nitrogen and phosphorus compared to the undisturbed soil for approximately 0.4 and 0.8 m of runoff loading, respectively. For the undisturbed soil, the nitrogen release was delayed, indicating that the soil disturbance accelerated the release of nitrogen into a very short time period. Leaving the soil undisturbed resulted in lower but still elevated effluent nitrogen concentrations over a longer period of time. For phosphorus, these results confirm prior research which demonstrated that the soil, if shown to be phosphorus-deficient during fertility testing, can remove phosphorus from runoff even when disturbed.

  19. Technical solutions for reducing indoor residential exposures to ultrafine particles from second-hand cigarette smoke infiltration

    DEFF Research Database (Denmark)

    Afshari, Alireza; Ardkapan, Siamak Rahimi; Bergsøe, Niels Christian

    2011-01-01

    was carried out in the field in a multi-storey building and cardboard and plastic foil of polyethylene were used for sealing the entire wooden floor in the receiving flat. Another technical solution examined was a novel air circulating ductwork. The efficiency of the novel air circulating ductwork...... in which smoke infiltrates from one flat to another and also to examine technical solutions for preventing or reducing infiltration of ultrafine particles from the source flat to the receiving flat. One of the technical solutions examined was sealing of the floor in the receiving flat. The study...

  20. Brooks–Corey Modeling by One-Dimensional Vertical Infiltration Method

    Directory of Open Access Journals (Sweden)

    Xuguang Xing

    2018-05-01

    Full Text Available The laboratory methods used for the soil water retention curve (SWRC construction and parameter estimation is time-consuming. A vertical infiltration method was proposed to estimate parameters α and n and to further construct the SWRC. In the present study, the relationships describing the cumulative infiltration and infiltration rate with the depth of the wetting front were established, and simplified expressions for estimating α and n parameters were proposed. The one-dimensional vertical infiltration experiments of four soils were conducted to verify if the proposed method would accurately estimate α and n. The fitted values of α and n, obtained from the RETC software, were consistent with the calculated values obtained from the infiltration method. The comparison between the measured SWRCs obtained from the centrifuge method and the calculated SWRCs that were based on the infiltration method displayed small values of root mean square error (RMSE, mean absolute percentage error (MAPE, and mean absolute error. SWMS_2D-based simulations of cumulative infiltration, based on the calculated α and n, remained consistent with the measured values due to small RMSE and MAPE values. The experiments verified the proposed one-dimensional vertical infiltration method, which has applications in field hydraulic parameter estimation.

  1. Measuring Outdoor Air Intake Rates into Existing Building

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William; Sullivan, Douglas; Cohen, Sebastian; Han, Hwataik

    2009-04-16

    Practical and accurate technologies are needed for continuously measuring and controlling outdoor air (OA) intake rates in commercial building heating, ventilating, and air conditioning (HVAC) systems. This project evaluated two new measurement approaches. Laboratory experiments determined that OA flow rates were measurable with errors generally less than 10 percent using electronic air velocity probes installed between OA intake louver blades or at the outlet face of louvers. High accuracy was maintained with OA flow rates as low as 15 percent of the maximum for the louvers. Thus, with this measurement approach HVAC systems do not need separate OA intakes for minimum OA supply. System calibration parameters are required for each unique combination of louver type and velocity sensor location but calibrations are not necessary for each system installation. The research also determined that the accuracy of measuring OA flow rates with velocity probes located in the duct downstream of the intake louver was not improved by installing honeycomb airflow straighteners upstream of the probes. Errors varied with type of upstream louver, were as high as 100 percent, and were often greater than 25 percent. In conclusion, use of electronic air velocity probes between the blades of OA intake louvers or at the outlet face of louvers is a highly promising means of accurately measuring rates of OA flow into HVAC systems. The use of electronic velocity probes downstream of airflow straighteners is less promising, at least with the relatively small OA HVAC inlet systems employed in this research.

  2. Isopleths of surface air concentration and surface air kerma rate due to a radioactive cloud released from a stack (3)

    International Nuclear Information System (INIS)

    Tachibana, Haruo; Kikuchi, Masamitsu; Sekita, Tsutomu; Yamaguchi, Takenori

    2004-06-01

    This report is a revised edition of 'Isopleths of Surface Air Concentration and Surface Air Absorbed Dose Rate due to a Radioactive Cloud Released from a Stack(II) '(JAERI-M 90-206) and based on the revised Nuclear Safety Guidelines reflected the ICRP1990 Recommendation. Characteristics of this report are the use of Air Karma Rate (Gy/h) instead of Air Absorbed Dose Rate (Gy/h), and the record of isopleths of surface air concentration and surface air karma rate on CD-ROM. These recorded data on CD-ROM can be printed out on paper and/or pasted on digital map by personal computer. (author)

  3. An evaluation of the effectiveness of air leakage sealing. Ener-Corp Management Ltd

    Energy Technology Data Exchange (ETDEWEB)

    1983-01-01

    A field study was carried out to evaluate the effectiveness of the sealing techniques for reducing air infiltration in houses. Tests were performed on single detached houses in Manitoba. The sample group consisted of 56 conventionally-constructed houses of varying size, style, occupancy and airtightness, and 26 nonstandard structures of smaller but identical size and age. Results show the median reduction in airtightness of the conventional structures, defined using the Equivalent Leakage Area at 10 Pascals (ELA/sub 10/), was 31.6%, with significant variations occurring both between individual houses and between different types of construction. The median reduction of the nonstandard houses was 42.5%, again with significant variations. An estimate was made of the naturally-occurring air infiltration rates for all the test houses. This analysis indicated that the sealing produced a median reduction in the infiltration rate of 32.8% for the conventional houses and 46.1% for the nonstandard ones. To relate the benefits of sealing in terms of its impact upon the space heating load, the data were used in conjuction with standardized house descriptions to simulate five different styles of houses using the HOTCAN energy analysis program. This analysis indicated that air leakage sealing would produce reductions in the space heating load (and bill) for most conventionally insulated houses averaging 10% to 15%. The results of this study are likely representative of houses constructed only in Manitoba and possibly Saskatchewan and Alberta. 3 refs., 9 figs., 11 tabs.

  4. Equivalence in Ventilation and Indoor Air Quality

    Energy Technology Data Exchange (ETDEWEB)

    Sherman, Max; Walker, Iain; Logue, Jennifer

    2011-08-01

    We ventilate buildings to provide acceptable indoor air quality (IAQ). Ventilation standards (such as American Society of Heating, Refrigerating, and Air-Conditioning Enginners [ASHRAE] Standard 62) specify minimum ventilation rates without taking into account the impact of those rates on IAQ. Innovative ventilation management is often a desirable element of reducing energy consumption or improving IAQ or comfort. Variable ventilation is one innovative strategy. To use variable ventilation in a way that meets standards, it is necessary to have a method for determining equivalence in terms of either ventilation or indoor air quality. This study develops methods to calculate either equivalent ventilation or equivalent IAQ. We demonstrate that equivalent ventilation can be used as the basis for dynamic ventilation control, reducing peak load and infiltration of outdoor contaminants. We also show that equivalent IAQ could allow some contaminants to exceed current standards if other contaminants are more stringently controlled.

  5. Modified design in new construction prevents infiltration of soil gas that carries radon

    International Nuclear Information System (INIS)

    Ericson, S.O.; Schmied, H.

    1987-01-01

    Dwellings located on permeable soil with strong exhalation of radon often get a contribution to indoor radon from infiltrating soil gas carrying radon from the ground into the building. 100 dwellings have been built on radon dangerous land with different modifications in design and construction in order to prevent infiltration of radon. Tight construction, ventilated crawl space, ventilation/depressurization of the capillary breaking layer (crushed stone), and mechanical ventilation with heat recovery by air to air heat exchangers or heat pumps have been tested. Added building costs and measured concentration of radon after construction and 3-5 years later are reported. It is concluded that it is possible to build radon protective and radon safe dwellings on any land. The added costs have ranged from zero to 4% of total building costs

  6. Infiltration and redistribution of water in soils

    International Nuclear Information System (INIS)

    Stroosnijder, L.

    1976-01-01

    The flow of the liquid phase through a soil can be predicted from pressure gradients. Different ways of predicting infiltration for irrigation of a basin were compared: numerical approximation; semi-analytical and analytical. A partly empirical equation was developed for description of rate of infiltration, after examination of existing equations. Under certain conditions, infiltration was influenced by under or over pressure of the trapped gas phase and by swelling of clays. Complex models for redistribution were of little value in practice, since they could not be generalized and required too many physical data about the soil. A scheme was developed that grouped techniques for estimating physical properties of soil, according to cost and expertise required. A new experimental technique based on gamma transmission is described for estimating the physical properties of the soil. (Auth.)

  7. Dry-season soil water repellency affects Tahoe Basin infiltration rates

    OpenAIRE

    Rice, Erin C; Grismer, Mark E

    2010-01-01

    Lake Tahoe’s declining clarity makes the identification of runoff and erosion sources and evaluation of control measures vitally important. We treated relatively undisturbed, native, forested sites of 10% to 15% slope with surfactant and used a rain-fall simulator to investigate the effects of repellency. We compared infiltration measurements made by the simulator and a mini-disk infiltrometer (MDI). Runoff was produced by all plots with untreated water, but only two of 12 plots with surfacta...

  8. Influence of loading rate and modes on infiltration of treated wastewater in soil-based constructed wetland.

    Science.gov (United States)

    Bisone, Sara; Gautier, Mathieu; Masson, Matthieu; Forquet, Nicolas

    2017-01-01

    Over the last 10 years soil-based constructed wetlands for discharge of treated wastewater (TWW) are commonly presented as a valuable option to provide tertiary treatment. The uncomplete knowledge in soil modifications and a lack of clear design practices laid the foundation of this work. The aim of this study was to determine optimal hydraulic loads and to observe the main critical parameters affecting treating performances and hydraulic loads acceptance. For this purpose, a soil rich in clay and backfill was chosen to perform column infiltration tests with TWW. Two loading rates and two loading modes were compared to study the influence of an intermittent feeding. Inlet and outlet waters were periodically analysed and columns were instrumented with balances, tensiometers, O 2 and temperature probes. Soil physico-chemical characteristics were also taken into account to better understand the modification of the soil. One of the main expectations of tertiary treatment is to improve phosphate removal. A particular attention was thus given to phosphorus retention. The interest of an intermittent feeding in presence of a soil with high clay content was showed. This study highlighted that an intermittent feeding could make possible the use of a clay-rich soil for water infiltration.

  9. Soil macropores: Control on infiltration, hillslope and surface hydrology on a reclaimed surface-mined watershed

    International Nuclear Information System (INIS)

    Guebert, M.D.; Gardner, T.W.

    1992-01-01

    The hydrologic response of a surface-mined watershed in central Pennsylvania is controlled by rapid macropore flow within the unsaturated man-made topsoil. Newly reclaimed surface-mined watersheds in central Pennsylvania exhibit low steady-state infiltration rates (1--2 cm/hr) and produce runoff dominated by infiltration-excess overland flow. However, within four years after reclamation, infiltration rates on some mine surfaces approach premined rates (8 cm/hr). As infiltration rate increases, the volume of infiltrated water increases, but the total porosity of minesoil matrix remains constant. There is little change in the surface discharge volume, indicating that infiltrated water continues to contribute to the basin surface discharge by the processes of throughflow and return flow. Throughflow in the topsoil horizon occurs in rapid response to rainfall input, producing large volumes of water with throughflow rates closely related to rainfall rates and with throughflow peaks following rainfall peaks by only minutes. Increased return flow alters the shape of the surface runoff hydrograph by slightly lagging behind infiltration excess overland flow. These changes in the shape of the surface runoff hydrograph reduce the potential for severe gully erosion on the reclaimed site. In addition, throughflow water remains predominantly in the topsoil horizon, and therefore has limited contact with potentially acid-producing backfill. Better understanding of macropore flow processes in reclaimed minesoils will help investigators evaluate past strategies and develop new reclamation techniques that will minimize the short-term surface erosional effects of mining and reclamation, while optimizing the long-term effluent and groundwater quality

  10. Water erosion and soil water infiltration in different stages of corn development and tillage systems

    Directory of Open Access Journals (Sweden)

    Daniel F. de Carvalho

    2015-11-01

    Full Text Available ABSTRACTThis study evaluated soil and water losses, soil water infiltration and infiltration rate models in soil tillage systems and corn (Zea mays, L. development stages under simulated rainfall. The treatments were: cultivation along contour lines, cultivation down the slope and exposed soil. Soil losses and infiltration in each treatment were quantified for rains applied using a portable simulator, at 0, 30, 60 and 75 days after planting. Infiltration rates were estimated using the models of Kostiakov-Lewis, Horton and Philip. Based on the obtained results, the combination of effects between soil tillage system and corn development stages reduces soil and water losses. The contour tillage system promoted improvements in soil physical properties, favoring the reduction of erosion in 59.7% (water loss and 86.6% (soil loss at 75 days after planting, and the increase in the stable infiltration rate in 223.3%, compared with the exposed soil. Associated to soil cover, contour cultivation reduces soil and water losses, and the former is more influenced by management. Horton model is the most adequate to represent soil water infiltration rate under the evaluated conditions.

  11. Effect of the settlement of sediments on water infiltration in two urban infiltration basins

    OpenAIRE

    LASSABATERE, Laurent; ANGULO JARAMILLO, R; GOUTALAND, David; LETELLIER, Laetitia; GAUDET, JP; WINIARSKI, Thierry; DELOLME, C

    2010-01-01

    The sealing of surfaces in urban areas makes storm water management compulsory. The suspended solids from surface runoff water accumulate in infiltration basins and may impact on water infiltration. This paper describes a study of the effect of the settlement of sedimentary layers on the water infiltration capacity of two urban infiltrations basins. In situ water infiltration experiments were performed (1) to quantify the effect of sediment on water infiltration at local scale and (2) to deri...

  12. 40 CFR 35.2120 - Infiltration/Inflow.

    Science.gov (United States)

    2010-07-01

    ... rainfall induced peak inflow rate results or will result in chronic operational problems during storm... during periods of high groundwater, the applicant shall build the project including sufficient capacity to transport and treat any existing infiltration. However, if the applicant believes any specific...

  13. Impacts of Changes of Indoor Air Pressure and Air Exchange Rate in Vapor Intrusion Scenarios.

    Science.gov (United States)

    Shen, Rui; Suuberg, Eric M

    2016-02-01

    There has, in recent years, been increasing interest in understanding the transport processes of relevance in vapor intrusion of volatile organic compounds (VOCs) into buildings on contaminated sites. These studies have included fate and transport modeling. Most such models have simplified the prediction of indoor air contaminant vapor concentrations by employing a steady state assumption, which often results in difficulties in reconciling these results with field measurements. This paper focuses on two major factors that may be subject to significant transients in vapor intrusion situations, including the indoor air pressure and the air exchange rate in the subject building. A three-dimensional finite element model was employed with consideration of daily and seasonal variations in these factors. From the results, the variations of indoor air pressure and air exchange rate are seen to contribute to significant variations in indoor air contaminant vapor concentrations. Depending upon the assumptions regarding the variations in these parameters, the results are only sometimes consistent with the reports of several orders of magnitude in indoor air concentration variations from field studies. The results point to the need to examine more carefully the interplay of these factors in order to quantitatively understand the variations in potential indoor air exposures.

  14. Comparison of deliverable and exhaustible pressurized air flow rates in laboratory gloveboxes

    International Nuclear Information System (INIS)

    Compton, J.A.

    1994-01-01

    Calculations were performed to estimate the maximum credible flow rates of pressurized air into Plutonium Process Support Laboratories gloveboxes. Classical equations for compressible fluids were used to estimate the flow rates. The calculated maxima were compared to another's estimates of glovebox exhaust flow rates and corresponding glovebox internal pressures. No credible pressurized air flow rate will pressurize a glovebox beyond normal operating limits. Unrestricted use of the pressurized air supply is recommended

  15. Effects of sodium polyacrylate on water retention and infiltration capacity of a sandy soil.

    Science.gov (United States)

    Zhuang, Wenhua; Li, Longguo; Liu, Chao

    2013-01-01

    Based on the laboratory study, the effects of sodium polyacrylate (SP) was investigated at 5 rates of 0, 0.08, 0.2, 0.5, and 1%, on water retention, saturated hydraulic conductivity(Ks), infiltration characteristic and water distribution profiles of a sandy soil. The results showed that water retention and available water capacity effectively increased with increasing SP rate. The Ks and the rate of wetting front advance and infiltration under certain pond infiltration was significantly reduced by increasing SP rate, which effectively reduced water in a sandy soil leaking to a deeper layer under the plough layer. The effect of SP on water distribution was obviously to the up layer and very little to the following deeper layers. Considering both the effects on water retention and infiltration capacity, it is suggested that SP be used to the sandy soil at concentrations ranging from 0.2 to 0.5%.

  16. Two-step infiltration of aluminum melts into Al-Ti-B4C-CuO powder mixture pellets

    Science.gov (United States)

    Zhang, Jingjing; Lee, Jung-Moo; Cho, Young-Hee; Kim, Su-Hyeon; Yu, Huashun

    2016-03-01

    Aluminum matrix composites with a high volume fraction of B4C and TiB2 were fabricated by a novel processing technique - a quick spontaneous infiltration process. The process combines a pressureless infiltration with the combustion reaction of Al-Ti-B4C-CuO in molten aluminum. The process is realized in a simple and economical way in which the whole process is performed in air in a few minutes. To verify the rapidity of the process, the infiltration kinetics was calculated based on the Washburn equation in which melt flows into a porous skeleton. However, there was a noticeable deviation from the calculated results with the experimental results. Considering the cross-sections of the samples at different processing times, a new infiltration model (two step infiltration) consisting of macro-infiltration and micro-infiltration is suggested. The calculated kinetics results in light of the proposed model agree well with the experimental results.

  17. Rapid Chemical Vapor Infiltration of Silicon Carbide Minicomposites at Atmospheric Pressure.

    Science.gov (United States)

    Petroski, Kenneth; Poges, Shannon; Monteleone, Chris; Grady, Joseph; Bhatt, Ram; Suib, Steven L

    2018-02-07

    The chemical vapor infiltration technique is one of the most popular for the fabrication of the matrix portion of a ceramic matrix composite. This work focuses on tailoring an atmospheric pressure deposition of silicon carbide onto carbon fiber tows using the methyltrichlorosilane (CH 3 SiCl 3 ) and H 2 deposition system at atmospheric pressure to create minicomposites faster than low pressure systems. Adjustment of the flow rate of H 2 bubbled through CH 3 SiCl 3 will improve the uniformity of the deposition as well as infiltrate the substrate more completely as the flow rate is decreased. Low pressure depositions conducted at 50 Torr deposit SiC at a rate of approximately 200 nm*h -1 , while the atmospheric pressure system presented has a deposition rate ranging from 750 nm*h -1 to 3.88 μm*h -1 . The minicomposites fabricated in this study had approximate total porosities of 3 and 6% for 10 and 25 SCCM infiltrations, respectively.

  18. Borehole environmental tracers for evaluating net infiltration and recharge through desert bedrock

    Science.gov (United States)

    Heilweil, V.M.; Solomon, D.K.; Gardner, P.M.

    2006-01-01

    Permeable bedrock aquifers in arid regions are being increasingly developed as water supplies, yet little is generally known about recharge processes and spatial and temporal variability. Environmental tracers from boreholes were used in this study to investigate net infiltration and recharge to the fractured Navajo Sandstone aquifer. Vadose zone tracer profiles at the Sand Hollow study site in southwestern Utah look similar to those of desert soils at other sites, indicating the predominance of matrix flow. However, recharge rates are generally higher in the Navajo Sandstone than in unconsolidated soils in similar climates because the sandstone matrix allows water movement but not root penetration. Water enters the vadose zone either as direct infiltration of precipitation through exposed sandstone and sandy soils or as focused infiltration of runoff. Net infiltration and recharge exhibit extreme spatial variability. High-recharge borehole sites generally have large amounts of vadose zone tritium, low chloride concentrations, and small vadose zone oxygen-18 evaporative shifts. Annual net-infiltration and recharge rates at different locations range from about 1 to 60 mm as determined using vadose zone tritium, 0 to 15 mm using vadose zone chloride, and 3 to 60 mm using groundwater chloride. Environmental tracers indicate a cyclical net-infiltration and recharge pattern, with higher rates earlier in the Holocene and lower rates during the late Holocene, and a return to higher rates during recent decades associated with anomalously high precipitation during the latter part of the 20th century. The slightly enriched stable isotopic composition of modern groundwater indicates this recent increase in precipitation may be caused by a stronger summer monsoon or winter southern Pacific El Nin??o storm track. ?? Soil Science Society of America.

  19. The Decline of Soil Infiltration Capacity Due To High Elevation Groundwater

    OpenAIRE

    Isri Ronald Mangangka

    2008-01-01

    Infiltration capacity of soil mainly depends on two factors; the particle size and the moisture content of the soil. Groundwater increases the soil moisture, not only below the water table but also within the capillary zone, above the water table. Field experiment in a high groundwater area was conducted to understand the relationship among the groundwater, soil moisture and infiltration capacity. Using a single ring infiltrometer, the effect of groundwater in the infiltration rate was observ...

  20. Effects of white grubs on soil water infiltration.

    Science.gov (United States)

    Romero-López, A A; Rodríguez-Palacios, E; Alarcón-Gutiérrez, E; Geissert, D; Barois, I

    2015-04-01

    Water infiltration rates k were measured in mesocosms with soil and "white grubs" of Ancognatha falsa (Arrow) (Coleoptera: Melolonthidae). Three third instars of A. falsa and three adult earthworms Pontoscolex corethrurus were selected, weighted, and introduced into the mesocosms setting three treatments: soil + A. falsa, soil + P. corethrurus, and control (soil without any macroorganism). The experiment had a completely random design with four replicates per treatment (n = 4). The infiltration rates of soil matrix were assessed in each mesocosms with a minidisk tension infiltrometer. Six measurements were made along the experiment. Results showed that larvae of A. falsa promoted a higher water infiltration in the soil, compared to the control. On day 7, k values were similar among treatments, but k values after 28 days and up to 100 days were much higher in the A. falsa treatment (k = 0.00025 cm s(-1)) if compared to control (k = 0.00011 cm s(-1)) and P. corethrurus (k = 0.00008 cm s(-1)) treatments. The k values were significantly higher in the presence of larvae of A. falsa compared to the control and P. corethrurus treatments. The larvae of A. falsa are potential candidates for new assays on soil water infiltration with different tensions to evaluate the role of pores and holes created by the larvae on soils.

  1. Magnesium based composites fabricated by low pressure infiltration

    International Nuclear Information System (INIS)

    Johansson, P.; Micski, A.; Savage, S.J.

    1993-01-01

    Magnesiumbased fiber composites have been produced by so called low pressure infiltration. The initial material consist of 'saffil' pre-forms and two magnesium alloys, Mg-9Al-1Zn and WE 54 (approximate composition Mg-5Y-1.5Nd-2(Tb,Er,Dy,Gd)-0.5Zr), and pure magnesium. The preforms consists of 10-30 vol% of short fibers linked together by SiO 2 or Al 2 O 3 . Three different routes have been tested in the search for a good low pressure infiltration method. The experiments cover corrosion testing in NaCl-solution, sliding wear, abrasion and erosion testing. Of the tested infiltration methods the best results were obtained in a resistance heated evacuable furnace, in which the metal was molted in a steel crucible and the preform was conveyed into the melt under protective atmosphere. The infiltration takes place at atmospheric pressure and the cooling is performed in a sealed tube in air. The microscopy studies shows that low pressure infiltrated composites contain considerable amounts of porosity in distinction from those fabricated by squeeze casting. The corrosion test has shown that in the tested environment the alloy WE 54 has good corrosion resistance while Mg-9Al-1Zn and pure magnesium show low corrosion resistance. The influence of fibres in the matrix seems to be very small. Both magnesium and the alloy Mg-9Al-1Zn show for two body abrasion an almost linear improvement of abrasion resistance with increased fiber content. Pure magnesium shows decreasing erosion resistance with increasing fibre content. The Mg-9Al-1Zn-alloy appears to show a maximum in erosion resistance at 10 vol% fibers. In sliding wear the materials show an optimum initial and steady state wear resistance at a fiber content of about 10%. In general Al 2 O 3 -binder gives better wear resistance than SiO 2 -binder. Tensile testing was performed on low pressure infiltrated and squeeze cast composites with WE 54 matrix. It shows that the low pressure infiltrated composites are inferior to those

  2. Pressureless infiltration of porous Al2O3 preform in molten 6061 commercial aluminium alloy

    International Nuclear Information System (INIS)

    Marin, J.; Olivares, L.; Moreno, C.; Ordonez, S.; Martinez, V.

    2001-01-01

    This paper presents an infiltration study of Al 2 O 3 samples containing, approximately, 40% of pores with 1μ average radios. These samples were totally infiltrated with Al-6061 at 1100 deg C for 24 hs in air. Microstructural analysis showed the presence of an alumina matrix infiltrated through mechanisms that combine reactive processes and capillarity, and thus being coherent with the presence of open and closed porosity. The metallographic analysis showed open porosity infiltrated with Al-6061 by capillarity, while SEM micrographs corresponding to this system also showed closed pores filled with metal, that was transported into the ceramic matrix through a reactivate infiltration mechanism. The EDAX analysis for the Al 2 O 3 /Al 6061 system showed areas rich in silicon and copper at the metal-ceramic interface, while the ceramic phase showed the presence of Mg. XRD identified the presence of the MgAl 2 O 4 spinel in the ceramic phase

  3. Influence of atmospheric rainfall to γ radiation Kerma rate in surface air

    International Nuclear Information System (INIS)

    Xu Zhe; Wan Jun; Yu Rongsheng

    2009-01-01

    Objective: To investigate the influence rule of the atmospheric Rainfall to the γ radiation Kerma rate in surface air in order to revise the result of its measurement during rainfall. Methods: The influence factors of rainfall to the measurement of the γ radiation Kerma rate in air were analyzed and then the differential equation of the correlation factors was established theoretically, and by resolving the equation, the mathematical model Was obtained. The model was discussed through several practical examples. Results: The mathematical model was coincided with the tendency of curve about the measured data on the influence rule of rainfall to the γ radiation Kerma rate in surface air. Conclusion: By using the theoretical formula in this article which is established to explain the relationship between the rainfall and the γ radiation Kerma rate in surface air, the influence of rainfall to the γ radiation Kerma rate in surface air could be correctly revised. (authors)

  4. Infiltrated carbon foam composites

    Science.gov (United States)

    Lucas, Rick D. (Inventor); Danford, Harry E. (Inventor); Plucinski, Janusz W. (Inventor); Merriman, Douglas J. (Inventor); Blacker, Jesse M. (Inventor)

    2012-01-01

    An infiltrated carbon foam composite and method for making the composite is described. The infiltrated carbon foam composite may include a carbonized carbon aerogel in cells of a carbon foam body and a resin is infiltrated into the carbon foam body filling the cells of the carbon foam body and spaces around the carbonized carbon aerogel. The infiltrated carbon foam composites may be useful for mid-density ablative thermal protection systems.

  5. The measurement of the indoor absorbed dose rate in air in Beijing

    International Nuclear Information System (INIS)

    Guo Mingqiang; Pan Ziqiang; Yi Nanchang; Wei Zemin; Zhang Chao; Wang Huamin; Zhu Wencai

    1985-01-01

    This paper describes the indoor absorbed dose rate in air in Beijing. The average indoor absorbed dose rate in air is 8.29 μrad/h. The ratio of indoor to outdoor absorbed dose rate for 849 buildings is 1.51

  6. [Characters of infiltration and preferential flow of black soil in Northeast China under different tillage patterns].

    Science.gov (United States)

    Li, Wen-Feng; Zhang, Xiao-Ping; Liang, Ai-Zhen; Shen, Yan; Shi, Xiu-Huan; Luo, Jin-Ming; Yang, Xue-Ming

    2008-07-01

    By using dye tracer and double-ring infiltrometer techniques, the characters of infiltration and preferential flow of black soil under no-tillage (NT) and fall moldboard plow (MP) were compared after six years continuous management. The results showed that the infiltration rate was higher under NT than under MP. When the infiltration reached steady, the infiltration rate and accumulative infiltration capacity under NT were 1.35 and 1.44 times as high as those under MP, respectively. The penetration depth of methylene blue reached a depth of 43 cm in NT soil, being 16 cm deeper than that in MP soil. Comparing with MP soil, NT soil had better development of pore structure and more biological pores, and presented better preferential flow character, which were of importance for water infiltration and soil and water conservation.

  7. Forced-air warming discontinued: periprosthetic joint infection rates drop

    Directory of Open Access Journals (Sweden)

    Scott D. Augustine

    2017-06-01

    Full Text Available Several studies have shown that the waste heat from forced-air warming (FAW escapes near the floor and warms the contaminated air resident near the floor. The waste heat then forms into convection currents that rise up and contaminate the sterile field above the surgical table. It has been shown that a single airborne bacterium can cause a periprosthetic joint infection (PJI following joint replacement surgery. We retrospectively compared PJI rates during a period of FAW to a period of air-free conductive fabric electric warming (CFW at three hospitals. Surgical and antibiotic protocols were held constant. The pooled multicenter data showed a decreased PJI rate of 78% following the discontinuation of FAW and a switch to air-free CFW (n=2034; P=0.002. The 78% reduction in joint implant infections observed when FAW was discontinued suggests that there is a link between the waste FAW heat and PJIs.

  8. Electrodes for solid oxide fuel cells based on infiltration of Co-based materials

    DEFF Research Database (Denmark)

    Samson, Alfred Junio; Søgaard, Martin; Bonanos, Nikolaos

    2012-01-01

    The electrochemical performance of cathodes produced by infiltration of nitrates corresponding to the nominal compositions Co3O4, LaCoO3, and La0.6Sr0.4Co1.05O3−δ into porous backbones of Ce0.9Gd0.1O1.95 has been studied. Characterization by electrochemical impedance spectroscopy at 600◦C in air...... revealed that the lowest electrode polarization (Rp) value is obtained for La0.6Sr0.4Co1.05O3−δ (0.062cm2), followed by LaCoO3 (0.079cm2), andCo3O4-infiltrated cathodes (0.27cm2). The surprisingly good performance of LaCoO3- and Co3O4-infiltrated cathodes demonstrate the peculiarities encountered...

  9. Scenario Studies on Effects of Soil Infiltration Rates, Land Slope, and Furrow Irrigation Characteristics on Furrow Irrigation-Induced Erosion.

    Science.gov (United States)

    Dibal, Jibrin M; Ramalan, A A; Mudiare, O J; Igbadun, H E

    2014-01-01

    Furrow irrigation proceeds under several soil-water-furrow hydraulics interaction dynamics. The soil erosion consequences from such interactions in furrow irrigation in Samaru had remained uncertain. A furrow irrigation-induced erosion (FIIE) model was used to simulate the potential severity of soil erosion in irrigated furrows due to interactive effects of infiltration rates, land slope, and some furrow irrigation characteristics under different scenarios. The furrow irrigation characteristics considered were furrow lengths, widths, and stream sizes. The model itself was developed using the dimensional analysis approach. The scenarios studied were the interactive effects of furrow lengths, furrow widths, and slopes steepness; infiltration rates and furrow lengths; and stream sizes, furrow lengths, and slopes steepness on potential furrow irrigation-induced erosion, respectively. The severity of FIIE was found to relate somewhat linearly with slope and stream size, and inversely with furrow lengths and furrow width. The worst soil erosion (378.05 t/ha/yr) was found as a result of the interactive effects of 0.65 m furrow width, 50 m furrow length, and 0.25% slope steepness; and the least soil erosion (0.013 t/ha/yr) was induced by the combined effects of 0.5 l/s, 200 m furrow length, and 0.05% slope steepness. Evidently considering longer furrows in furrow irrigation designs would be a better alternative of averting excessive FIIE.

  10. The soil apparent infiltrability observed with ponded infiltration experiment in a permanent grid of infiltration rings

    Czech Academy of Sciences Publication Activity Database

    Votrubová, J.; Jelínková, V.; Němcová, R.; Tesař, Miroslav; Vogel, T.; Císlerová, M.

    2010-01-01

    Roč. 12, - (2010), s. 11898 ISSN 1607-7962. [European Geosciences Union General Assembly 2010. 02.05.2010-07.05.2010, Wienna] R&D Projects: GA ČR GA205/08/1174 Institutional research plan: CEZ:AV0Z20600510 Keywords : soil hydraulic conductivity * infiltration * infiltration ring Subject RIV: DA - Hydrology ; Limnology

  11. Monitoring and modeling infiltration-recharge dynamics of managed aquifer recharge with desalinated seawater

    Science.gov (United States)

    Ganot, Yonatan; Holtzman, Ran; Weisbrod, Noam; Nitzan, Ido; Katz, Yoram; Kurtzman, Daniel

    2017-09-01

    We study the relation between surface infiltration and groundwater recharge during managed aquifer recharge (MAR) with desalinated seawater in an infiltration pond, at the Menashe site that overlies the northern part of the Israeli Coastal Aquifer. We monitor infiltration dynamics at multiple scales (up to the scale of the entire pond) by measuring the ponding depth, sediment water content and groundwater levels, using pressure sensors, single-ring infiltrometers, soil sensors, and observation wells. During a month (January 2015) of continuous intensive MAR (2.45 × 106 m3 discharged to a 10.7 ha area), groundwater level has risen by 17 m attaining full connection with the pond, while average infiltration rates declined by almost 2 orders of magnitude (from ˜ 11 to ˜ 0.4 m d-1). This reduction can be explained solely by the lithology of the unsaturated zone that includes relatively low-permeability sediments. Clogging processes at the pond-surface - abundant in many MAR operations - are negated by the high-quality desalinated seawater (turbidity ˜ 0.2 NTU, total dissolved solids ˜ 120 mg L-1) or negligible compared to the low-permeability layers. Recharge during infiltration was estimated reasonably well by simple analytical models, whereas a numerical model was used for estimating groundwater recharge after the end of infiltration. It was found that a calibrated numerical model with a one-dimensional representative sediment profile is able to capture MAR dynamics, including temporal reduction of infiltration rates, drainage and groundwater recharge. Measured infiltration rates of an independent MAR event (January 2016) fitted well to those calculated by the calibrated numerical model, showing the model validity. The successful quantification methodologies of the temporal groundwater recharge are useful for MAR practitioners and can serve as an input for groundwater flow models.

  12. SIMULATION OF NET INFILTRATION FOR MODERN AND POTENTIAL FUTURE CLIMATES

    Energy Technology Data Exchange (ETDEWEB)

    J.A. Heveal

    2000-06-16

    This Analysis/Model Report (AMR) describes enhancements made to the infiltration model documented in Flint et al. (1996) and documents an analysis using the enhanced model to generate spatial and temporal distributions over a model domain encompassing the Yucca Mountain site, Nevada. Net infiltration is the component of infiltrated precipitation, snowmelt, or surface water run-on that has percolated below the zone of evapotranspiration as defined by the depth of the effective root zone, the average depth below the ground surface (at a given location) from which water is removed by evapotranspiration. The estimates of net infiltration are used for defining the upper boundary condition for the site-scale 3-dimensional Unsaturated-Zone Ground Water Flow and Transport (UZ flow and transport) Model (CRWMS M&O 2000a). The UZ flow and transport model is one of several process models abstracted by the Total System Performance Assessment model to evaluate expected performance of the potential repository at Yucca Mountain, Nevada, in terms of radionuclide transport (CRWMS M&O 1998). The net-infiltration model is important for assessing potential repository-system performance because output from this model provides the upper boundary condition for the UZ flow and transport model that is used to generate flow fields for evaluating potential radionuclide transport through the unsaturated zone. Estimates of net infiltration are provided as raster-based, 2-dimensional grids of spatially distributed, time-averaged rates for three different climate stages estimated as likely conditions for the next 10,000 years beyond the present. Each climate stage is represented using a lower bound, a mean, and an upper bound climate and corresponding net-infiltration scenario for representing uncertainty in the characterization of daily climate conditions for each climate stage, as well as potential climate variability within each climate stage. The set of nine raster grid maps provide spatially

  13. SIMULATION OF NET INFILTRATION FOR MODERN AND POTENTIAL FUTURE CLIMATES

    International Nuclear Information System (INIS)

    J.A. Heveal

    2000-01-01

    This Analysis/Model Report (AMR) describes enhancements made to the infiltration model documented in Flint et al. (1996) and documents an analysis using the enhanced model to generate spatial and temporal distributions over a model domain encompassing the Yucca Mountain site, Nevada. Net infiltration is the component of infiltrated precipitation, snowmelt, or surface water run-on that has percolated below the zone of evapotranspiration as defined by the depth of the effective root zone, the average depth below the ground surface (at a given location) from which water is removed by evapotranspiration. The estimates of net infiltration are used for defining the upper boundary condition for the site-scale 3-dimensional Unsaturated-Zone Ground Water Flow and Transport (UZ flow and transport) Model (CRWMS M and O 2000a). The UZ flow and transport model is one of several process models abstracted by the Total System Performance Assessment model to evaluate expected performance of the potential repository at Yucca Mountain, Nevada, in terms of radionuclide transport (CRWMS M and O 1998). The net-infiltration model is important for assessing potential repository-system performance because output from this model provides the upper boundary condition for the UZ flow and transport model that is used to generate flow fields for evaluating potential radionuclide transport through the unsaturated zone. Estimates of net infiltration are provided as raster-based, 2-dimensional grids of spatially distributed, time-averaged rates for three different climate stages estimated as likely conditions for the next 10,000 years beyond the present. Each climate stage is represented using a lower bound, a mean, and an upper bound climate and corresponding net-infiltration scenario for representing uncertainty in the characterization of daily climate conditions for each climate stage, as well as potential climate variability within each climate stage. The set of nine raster grid maps provide

  14. Stormwater infiltration and surface runoff pollution reduction performance of permeable pavement layers.

    Science.gov (United States)

    Niu, Zhi-Guang; Lv, Zhi-Wei; Zhang, Ying; Cui, Zhen-Zhen

    2016-02-01

    In this paper, the laboratory-scale permeable pavement layers, including a surface permeable brick layer, coarse sand bedding layers (thicknesses = 2, 3.5, and 5 cm), and single-graded gravel sub-base layers (thicknesses = 15, 20, 25, and 30 cm), were built to evaluate stormwater infiltration and surface runoff pollution reduction performance. And, the infiltration rate (I) and concentrations of suspended solids (SS), total phosphorus (TP), chemical oxygen demand (COD), ammonia nitrogen, and total nitrogen (TN) were measured under the simulated rainfall intensity of 72.4 mm/h over duration of 60 min. The results indicate that the thickness factor primarily influences the infiltration rate and pollutant removal rate. The highest steady infiltration rate was for surface brick layer 51.0 mm/h, for 5-cm sand bedding layer 32.3 mm/h, and for 30-cm gravel sub-base layer 42.3 mm/h, respectively. The SS average removal rate was relative higher (79.8 ∼ 98.6 %) for all layers due to the interception and filtration. The average removal rates of TP and COD were for surface layer 71.2 and 24.1 %, for 5-cm bedding layer 54.8 and 9.0 %, and for 20-cm sub-base layer 72.2 and 26.1 %. Ammonia nitrogen and TN cannot steadily be removed by layers according to the experiment results. The optimal thickness of bedding sands was 5 cm, and that of sub-base gravels was 20 ∼ 30 cm.

  15. Surface biosolids application: effects on infiltration, erosion, and soil organic carbon in Chihuahuan Desert grasslands and shrublands.

    Science.gov (United States)

    Moffet, C A; Zartman, R E; Wester, D B; Sosebee, R E

    2005-01-01

    Land application of biosolids is a beneficial-use practice whose ecological effects depend in part on hydrological effects. Biosolids were surface-applied to square 0.5-m2 plots at four rates (0, 7, 34, and 90 dry Mg ha(-1)) on each of three soil-cover combinations in Chihuahuan Desert grassland and shrubland. Infiltration and erosion were measured during two seasons for three biosolids post-application ages. Infiltration was measured during eight periods of a 30-min simulated rain. Biosolids application affected infiltration rate, cumulative infiltration, and erosion. Infiltration increased with increasing biosolids application rate. Application of biosolids at 90 dry Mg ha(-1) increased steady-state infiltration rate by 1.9 to 7.9 cm h(-1). Most of the measured differences in runoff among biosolids application rates were too large to be the result of interception losses and/or increased hydraulic gradient due to increased roughness. Soil erosion was reduced by the application of biosolids; however, the extent of reduction in erosion depended on the initial erodibility of the site. Typically, the greatest marginal reductions in erosion were achieved at the lower biosolids application rates (7 and 34 dry Mg ha(-1)); the difference in erosion between 34 and 90 dry Mg ha(-1) biosolids application rates was not significant. Surface application of biosolids has important hydrological consequences on runoff and soil erosion in desert grasslands that depend on the rate of biosolids applied, and the site and biosolids characteristics.

  16. Simulating the volatilization of solvents in unsaturated soils during laboratory and field infiltration experiments

    Science.gov (United States)

    Cho, H. Jean; Jaffe, Peter R.; Smith, James A.

    1993-01-01

    This paper describes laboratory and field experiments which were conducted to study the dynamics of trichloroethylene (TCE) as it volatilized from contaminated groundwater and diffused in the presence of infiltrating water through the unsaturated soil zone to the land surface. The field experiments were conducted at the Picatinny Arsenal, which is part of the United States Geological Survey Toxic Substances Hydrology Program. In both laboratory and field settings the gas and water phase concentrations of TCE were not in equilibrium during infiltration. Gas-water mass transfer rate constants were calibrated to the experimental data using a model in which the water phase was treated as two phases: a mobile water phase and an immobile water phase. The mass transfer limitations of a volatile organic compound between the gas and liquid phases were described explicitly in the model. In the laboratory experiment the porous medium was nonsorbing, and water infiltration rates ranged from 0.076 to 0.28 cm h−1. In the field experiment the water infiltration rate was 0.34 cm h−1, and sorption onto the soil matrix was significant. The laboratory-calibrated gas-water mass transfer rate constant is 3.3×10−4 h−1 for an infiltration rate of 0.076 cm h−1 and 1.4×10−3 h−1 for an infiltration rate of 0.28 cm h−1. The overall mass transfer rate coefficients, incorporating the contribution of mass transfer between mobile and immobile water phases and the variation of interfacial area with moisture content, range from 3×10−4 h−1 to 1×10−2 h−1. A power law model relates the gas-water mass transfer rate constant to the infiltration rate and the fraction of the water phase which is mobile. It was found that the results from the laboratory experiments could not be extrapolated to the field. In order to simulate the field experiment the very slow desorption of TCE from the soil matrix was incorporated into the mathematical model. When desorption from the

  17. Sewage Effluent Infiltrates Frozen Forest Soil

    Science.gov (United States)

    Alfred Ray Harris

    1976-01-01

    Secondarily treated sewage effluent, applied at the rate of 1 and 2 inches per week, infiltrated a frozen Sparta sand soil forested with jack pine and scrub oak. Maximum frost depth in treated plots averaged 60 cm and in check plots averages 35 cm. Nitrogen was mobile with some accumulation. Phosphorus was absorbed.

  18. Facial infiltrative lipomatosis

    International Nuclear Information System (INIS)

    Haloi, A.K.; Ditchfield, M.; Pennington, A.; Philips, R.

    2006-01-01

    Although there are multiple case reports and small series concerning facial infiltrative lipomatosis, there is no composite radiological description of the condition. Radiological evaluation of facial infiltrative lipomatosis using plain film, sonography, CT and MRI. We radiologically evaluated four patients with facial infiltrative lipomatosis. Initial plain radiographs of the face were acquired in all patients. Three children had an initial sonographic examination to evaluate the condition, followed by MRI. One child had a CT and then MRI. One child had abnormalities on plain radiographs. Sonographically, the lesions were seen as ill-defined heterogeneously hypoechoic areas with indistinct margins. On CT images, the lesions did not have a homogeneous fat density but showed some relatively more dense areas in deeper parts of the lesions. MRI provided better delineation of the exact extent of the process and characterization of facial infiltrative lipomatosis. Facial infiltrative lipomatosis should be considered as a differential diagnosis of vascular or lymphatic malformation when a child presents with unilateral facial swelling. MRI is the most useful single imaging modality to evaluate the condition, as it provides the best delineation of the exact extent of the process. (orig.)

  19. Effects of Thinning Intensities on Soil Infiltration and Water Storage Capacity in a Chinese Pine-Oak Mixed Forest

    OpenAIRE

    Chen, Lili; Yuan, Zhiyou; Shao, Hongbo; Wang, Dexiang; Mu, Xingmin

    2014-01-01

    Thinning is a crucial practice in the forest ecosystem management. The soil infiltration rate and water storage capacity of pine-oak mixed forest under three different thinning intensity treatments (15%, 30%, and 60%) were studied in Qinling Mountains of China. The thinning operations had a significant influence on soil infiltration rate and water storage capacity. The soil infiltration rate and water storage capacity in different thinning treatments followed the order of control (nonthinning):

  20. A study of pipe flow rate measurement using air-coupled ultrasound

    International Nuclear Information System (INIS)

    Tsukada, Keisuke; Tsuzuki, Nobuyoshi; Kikura, Hiroshige

    2013-01-01

    A non-contact flow meter employing air-coupled ultrasound is developed in this research. Ultrasonic flow meter is applied to the higher accuracy flow rate measurement, compared with pressure difference flow meter. However, ultrasonic flow meter has difficulty to measure in severe conditions such as in the condition of high temperature, high pressure condition, and radioactive materials in fluid. Especially, in high temperature condition, piezoelectric device in ultrasonic sensors lose the piezoelectricity, and it becomes difficult to transmit or detect ultrasound. Thus, in this research, ultrasonic sensors are fixed in the air. Ultrasonic sensors transmit and detect ultrasound through air, and measure the flow rate in the pipe. However, most of ultrasound is refracted and reflected at the boundaries between air and the pipe. And detected signals are weak. To increase the signal level, we developed focusing ultrasonic sensors that was optimized for the pipe flow measurement. And employing these focusing sensors the flow rate measurement has been done in order to evaluate the air-coupled ultrasonic flow meter by the ultrasonic beam focusing technique. (author)

  1. Can urban tree roots improve infiltration through compacted subsoils for stormwater management?

    Science.gov (United States)

    Bartens, Julia; Day, Susan D; Harris, J Roger; Dove, Joseph E; Wynn, Theresa M

    2008-01-01

    Global land use patterns and increasing pressures on water resources demand creative urban stormwater management. Strategies encouraging infiltration can enhance groundwater recharge and water quality. Urban subsoils are often relatively impermeable, and the construction of many stormwater detention best management practices (D-BMPs) exacerbates this condition. Root paths can act as conduits for water, but this function has not been demonstrated for stormwater BMPs where standing water and dense subsoils create a unique environment. We examined whether tree roots can penetrate compacted subsoils and increase infiltration rates in the context of a novel infiltration BMP (I-BMP). Black oak (Quercus velutina Lam.) and red maple (Acer rubrum L.) trees, and an unplanted control, were installed in cylindrical planting sleeves surrounded by clay loam soil at two compaction levels (bulk density = 1.3 or 1.6 g cm(-3)) in irrigated containers. Roots of both species penetrated the more compacted soil, increasing infiltration rates by an average of 153%. Similarly, green ash (Fraxinus pennsylvanica Marsh.) trees were grown in CUSoil (Amereq Corp., New York) separated from compacted clay loam subsoil (1.6 g cm(-3)) by a geotextile. A drain hole at mid depth in the CUSoil layer mimicked the overflow drain in a stormwater I-BMP thus allowing water to pool above the subsoil. Roots penetrated the geotextile and subsoil and increased average infiltration rate 27-fold compared to unplanted controls. Although high water tables may limit tree rooting depth, some species may be effective tools for increasing water infiltration and enhancing groundwater recharge in this and other I-BMPs (e.g., raingardens and bioswales).

  2. Infiltration behaviour of elemental mercury DNAPL in fully and partially water saturated porous media

    Science.gov (United States)

    D'Aniello, Andrea; Hartog, Niels; Sweijen, Thomas; Pianese, Domenico

    2018-02-01

    both air and water, depending on the initial water distribution within the pores. This indicates that the conventional wettability hierarchy, in which the NAPL has an intermediate wetting state between the air and the water phases, is not valid for liquid elemental mercury. Therefore, for future modelling of elemental mercury DNAPL infiltration behaviour in variably water saturated porous media, a different formulation of the governing constitutive relations will be required.

  3. Near-surface air temperature lapse rates in Xinjiang, northwestern China

    Science.gov (United States)

    Du, Mingxia; Zhang, Mingjun; Wang, Shengjie; Zhu, Xiaofan; Che, Yanjun

    2018-02-01

    Lapse rates of near-surface (2 m) air temperature are important parameters in hydrologic and climate simulations, especially for the mountainous areas without enough in-situ observations. In Xinjiang, northwestern China, the elevations range from higher than 7000 m to lower than sea level, but the existing long-term meteorological measurements are limited and distributed unevenly. To calculate lapse rates in Xinjiang, the daily data of near-surface air temperature ( T min, T ave, and T max) were measured by automatic weather stations from 2012 to 2014. All the in situ observation stations were gridded into a network of 1.5° (latitude) by 1.5° (longitude), and the spatial distribution and the daily, monthly, seasonal variations of lapse rates for T min, T ave, and T max in Xinjiang are analyzed. The Urumqi River Basin has been considered as a case to study the influence of elevation, aspect, and the wet and dry air conditions to the T min, T ave, and T max lapse rates. Results show that (1) the lapse rates for T min, T ave, and T max vary spatially during the observation period. The spatial diversity of T min lapse rates is larger than that of T ave, and that of T max is the smallest. For each season, T max lapse rates have more negative values than T ave lapse rates which are steeper than T min lapse rates. The weakest spatial diversity usually appears in July throughout a year. (2) The comparison for the three subregions (North, Middle, and South region) exhibits that lapse rates have similar day-to-day and month-to-month characteristics which present shallower values in winter months and steeper values in summer months. The T ave lapse rates in North region are shallower than those in Middle and South region, and the steepest T ave lapse rates of the three regions all appear in April. T min lapse rates are shallower than T max lapse rates. The maximum medians of T min and T max lapse rates for each grid in the three regions all appear in January, whereas the

  4. WATER INFILTRATION IN TWO CULTIVATED SOILS IN SOUTHERN BRAZIL

    Directory of Open Access Journals (Sweden)

    Ildegardis Bertol

    2015-04-01

    Full Text Available Infiltration is the passage of water through the soil surface, influenced by the soil type and cultivation and by the soil roughness, surface cover and water content. Infiltration absorbs most of the rainwater and is therefore crucial for planning mechanical conservation practices to manage runoff. This study determined water infiltration in two soil types under different types of management and cultivation, with simulated rainfall of varying intensity and duration applied at different times, and to adjust the empirical model of Horton to the infiltration data. The study was conducted in southern Brazil, on Dystric Nitisol (Nitossolo Bruno aluminoférrico húmico and Humic Cambisol (Cambissolo Húmico alumínico léptico soils to assess the following situations: simulated rains on the Nitisol from 2001 to 2012 in 31 treatments, differing in crop type, sowing direction, type of soil opener on the seeder, amount and type of crop residue and amount of liquid swine manure applied; on the Cambisol, rains were simlated from 2006 to 2012 and 18 treatments were evaluated, differing in crop, seeding direction and crop residue type. The constant of the water infiltration rate into the soil varies significantly with the soil type (30.2 mm h-1 in the Nitisol and 6.6 mm h-1 in the Cambisol, regardless of the management system, application time and rain intensity and duration. At the end of rainfalls, soil-water infiltration varies significantly with the management system, with the timing of application and rain intensity and duration, with values ranging from 13 to 59 mm h-1, in the two studied soils. The characteristics of the sowing operation in terms of relief, crop type and amount and type of crop residue influenced soil water infiltration: in the Nitisol, the values of contour and downhill seeding vary between 27 and 43 mm h-1, respectively, with crop residues of corn, wheat and soybean while in the Cambisol, the variation is between 2 and 36 mm h-1

  5. Influence of Deforestation on Infiltration and Erosion in the Brazilian Caatinga

    Science.gov (United States)

    Leite, P. A.; Souza, E.; Gomes, R. J.; Jacques, Y.; Cantalice, J. R. B.; Wilcox, B. P.

    2015-12-01

    Population growth and changes in land use are leading to increasing rates of deforestation and land degradation in the Brazilian Caatinga—a semiarid tropical forest. The influence of deforestation and subsequent recovery on soil hydrological properties and erosion are poorly understood. To investigate the influence of forest regeneration stage on soil hydrological processes, we conducted small plot rainfall simulation experiments on (1) a degraded pasture, recently abandoned; (2) an abandoned pasture left for natural recovery in the past seven years; (3) a 40 year old regenerating forestland; and (4) an old-growth forestland. In addition, we determined infiltration rates using single rings (following the Beerkan Method) and in the laboratory we applied the constant head method to soil core samples. Hydraulic parameters will be obtained using the BEST method with SciLab software and statistical analysis of the data will be carried in R. We found that infiltration rates were highest and erosion the lowest in the old-growth forest. Surprisingly, differences in both infiltration and erosion rates were quite small in the other sites. These results suggest that significant time is required following deforestation for recovery of soil hydrological properties.

  6. Laboratory testing on infiltration in single synthetic fractures

    Science.gov (United States)

    Cherubini, Claudia; Pastore, Nicola; Li, Jiawei; Giasi, Concetta I.; Li, Ling

    2017-04-01

    An understanding of infiltration phenomena in unsaturated rock fractures is extremely important in many branches of engineering for numerous reasons. Sectors such as the oil, gas and water industries are regularly interacting with water seepage through rock fractures, yet the understanding of the mechanics and behaviour associated with this sort of flow is still incomplete. An apparatus has been set up to test infiltration in single synthetic fractures in both dry and wet conditions. To simulate the two fracture planes, concrete fractures have been moulded from 3D printed fractures with varying geometrical configurations, in order to analyse the influence of aperture and roughness on infiltration. Water flows through the single fractures by means of a hydraulic system composed by an upstream and a downstream reservoir, the latter being subdivided into five equal sections in order to measure the flow rate in each part to detect zones of preferential flow. The fractures have been set at various angles of inclination to investigate the effect of this parameter on infiltration dynamics. The results obtained identified that altering certain fracture parameters and conditions produces relevant effects on the infiltration process through the fractures. The main variables influencing the formation of preferential flow are: the inclination angle of the fracture, the saturation level of the fracture and the mismatch wavelength of the fracture.

  7. Perfluorinated compounds in infiltrated river rhine water and infiltrated rainwater in coastal dunes.

    Science.gov (United States)

    Eschauzier, Christian; Haftka, Joris; Stuyfzand, Pieter J; de Voogt, Pim

    2010-10-01

    Different studies have shown that surface waters contain perfluorinated compounds (PFCs) in the low ng/L range. Surface waters are used to produce drinking water and PFCs have been shown to travel through the purification system and form a potential threat to human health. The specific physicochemical properties of PFCs cause them to be persistent and some of them to be bioaccumulative and toxic in the environment. This study investigates the evolvement of PFC concentrations in Rhine water and rainwater during dune water infiltration processes over a transect in the dune area of the western part of The Netherlands. The difference between infiltrated river water and rainwater in terms of PFC composition was investigated. Furthermore, isomer profiles were investigated. The compound perfluorobutanesulfonate (PFBS) was found at the highest concentrations of all PFCs investigated, up to 37 ng/L in infiltrated river water (71 ± 13% of ΣPFCs). This is in contrast with the predominant occurrence of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS) reported in literature. The concentrations of PFBS found in infiltrated river Rhine water were significantly higher than those in infiltrated rainwater. For perfluorohexanesulfonate (PFHxS) the opposite was found: infiltrated rainwater contained more than infiltrated river water. The concentrations of PFOA, perfluorohexanoic acid (PFHxA), perfluoroheptanoic acid (PFHpA), PFBS, PFOS, and PFHxS in infiltrated river water showed an increasing trend with decreasing age of the water. The relative contribution of the branched PFOA and PFOS isomers to total concentrations of PFOA and PFOS showed a decreasing trend with decreasing age of the water.

  8. Nutrient Release from Disturbance of Infiltration System Soils during Construction

    OpenAIRE

    Daniel P. Treese; Shirley E. Clark; Katherine H. Baker

    2012-01-01

    Subsurface infiltration and surface bioretention systems composed of engineered and/or native soils are preferred tools for stormwater management. However, the disturbance of native soils, especially during the process of adding amendments to improve infiltration rates and pollutant removal, may result in releases of nutrients in the early life of these systems. This project investigated the nutrient release from two soils, one disturbed and one undisturbed. The disturbed soil was collected i...

  9. A comparison of two methods of infiltration in breast reduction surgery.

    Science.gov (United States)

    Armour, A D; Rotenberg, B W; Brown, M H

    2001-08-01

    The superwet technique has been shown in previous studies to dramatically reduce blood loss in breast reduction surgery, compared with standard infiltration. A retrospective chart review of 303 consecutive patients undergoing bilateral breast reduction surgery was undertaken to demonstrate additional differences in complication rate, operative time, or sponge use in the operating room. In this series, 132 consecutive patients received standard infiltration along incision lines (25 cc per breast of 1:100,000 epinephrine), and 171 patients received superwet infiltration with 240 cc per breast of 1:1,000,000 epinephrine. The average operative time was significantly reduced in the superwet group, from 78.5 minutes to 70.7 minutes (p loss, the superwet infiltration effectively reduces operative time and sponge use without increasing complications in breast reduction surgery.

  10. Statistical methods towards more efficient infiltration measurements.

    Science.gov (United States)

    Franz, T; Krebs, P

    2006-01-01

    A comprehensive knowledge about the infiltration situation in a catchment is required for operation and maintenance. Due to the high expenditures, an optimisation of necessary measurement campaigns is essential. Methods based on multivariate statistics were developed to improve the information yield of measurements by identifying appropriate gauge locations. The methods have a high degree of freedom against data needs. They were successfully tested on real and artificial data. For suitable catchments, it is estimated that the optimisation potential amounts up to 30% accuracy improvement compared to nonoptimised gauge distributions. Beside this, a correlation between independent reach parameters and dependent infiltration rates could be identified, which is not dominated by the groundwater head.

  11. Isothermal and non-isothermal infiltration and deuterium transport: a case study in a soil column from a headwater catchment

    Czech Academy of Sciences Publication Activity Database

    Sobotková, M.; Sněhota, M.; Budínová, E.; Tesař, Miroslav

    2017-01-01

    Roč. 65, č. 3 (2017), s. 234-243 ISSN 0042-790X Grant - others:GA ČR(CZ) GA14-03691S Institutional support: RVO:67985874 Keywords : isothermal infiltration * non-isothermal infiltration * column leaching * breakthrough curve * deuterium * viscosity * capillary trapping * entrapped air * permeability Subject RIV: DA - Hydrology ; Limnology OBOR OECD: Environmental sciences (social aspects to be 5.7) Impact factor: 1.654, year: 2016

  12. Simulation of Net Infiltration for Present-Day and Potential Future Climates

    Energy Technology Data Exchange (ETDEWEB)

    D. Levitt

    2004-11-09

    The purpose of this model report is to document the infiltration model used to estimate upper-bound, mean, and lower-bound spatially-distributed average annual net infiltration rates for present-day and potential future climates at Yucca Mountain, Nevada. Net infiltration is the component of infiltrated precipitation, snowmelt, or surface water run-on that has percolated below the zone of evapotranspiration as defined by the depth of the effective root zone. The estimates of net infiltration are primarily used for defining the upper boundary condition for the site-scale three-dimensional unsaturated zone (UZ) model. The UZ flow model is one of several process models abstracted by the total system performance assessment (TSPA) model used to evaluate performance of the repository at Yucca Mountain, Nevada. The net-infiltration model is important for assessing repository-system performance because output from this model provides the upper boundary condition for the UZ flow model used to generate flow fields; water percolating downward from the UZ will be the principal means by which radionuclides are potentially released to the saturated zone (SZ). The SZ is the principal pathway to the biosphere where the reasonably maximally exposed individual (RMEI) is exposed to radionuclides.

  13. Simulation of Net Infiltration for Present-Day and Potential Future Climates

    International Nuclear Information System (INIS)

    Levitt, D.

    2004-01-01

    The purpose of this model report is to document the infiltration model used to estimate upper-bound, mean, and lower-bound spatially-distributed average annual net infiltration rates for present-day and potential future climates at Yucca Mountain, Nevada. Net infiltration is the component of infiltrated precipitation, snowmelt, or surface water run-on that has percolated below the zone of evapotranspiration as defined by the depth of the effective root zone. The estimates of net infiltration are primarily used for defining the upper boundary condition for the site-scale three-dimensional unsaturated zone (UZ) model. The UZ flow model is one of several process models abstracted by the total system performance assessment (TSPA) model used to evaluate performance of the repository at Yucca Mountain, Nevada. The net-infiltration model is important for assessing repository-system performance because output from this model provides the upper boundary condition for the UZ flow model used to generate flow fields; water percolating downward from the UZ will be the principal means by which radionuclides are potentially released to the saturated zone (SZ). The SZ is the principal pathway to the biosphere where the reasonably maximally exposed individual (RMEI) is exposed to radionuclides

  14. Buccal infiltration versus inferior alveolar nerve block in mandibular 2nd premolars with irreversible pulpitis.

    Science.gov (United States)

    Yilmaz, K; Tunga, U; Ozyurek, T

    2018-04-01

    The purpose of this study is to compare the success rates of inferior alveolar nerve block (IANB) and buccal infiltration anesthesia of mandibular second premolar with irreversible pulpitis and to evaluate the level of patient discomfort with these methods. Forty patients, who had irreversible pulpitis in the mandibular 2 nd premolar teeth, were included in the study. Patients were randomly distributed in two groups. In one group IANB, in the other group buccal infiltration anesthesia were performed. The efficacy of these two different anesthesia techniques on the related teeth was investigated with the Heft-Parker visual analog scale. In addition, with a pulse oximetry device, the changes in the patients' heart rates were compared between the groups. The obtained data were evaluated statistically. Both anesthesia techniques reduced the pain significantly in patients before the administration (P 0.05). Both of the anesthesia techniques increased the heart rate (P < 0.05). The increase in the heart rate of the patients was significantly higher in the buccal infiltration anesthesia group than the other anesthesia group (P < 0.05). Within the limitation of this in vivo study, there was no difference between the efficacies of the buccal infiltration anesthesia and IANB anesthesia in the mandibular 2 nd premolar teeth with irreversible pulpitis. Buccal infiltration anesthesia caused more discomfort in the patients compared with the IANB during the administration.

  15. Buccal Infiltration versus Inferior Alveolar Nerve Block in Mandibular ...

    African Journals Online (AJOL)

    2018-04-04

    Apr 4, 2018 ... the changes in the patients' heart rates were compared between the groups. The obtained data were evaluated statistically. ... The increase in the heart rate of the patients was significantly higher in the buccal infiltration ..... in rat dorsal root ganglion neurons. J Neurosci 1992;12:2104‑11. 4. Tortamano IP ...

  16. Basement radon entry and stack driven moisture infiltration reduced by active soil depressurization

    Science.gov (United States)

    C.R. Boardman; Samuel V. Glass

    2015-01-01

    This case study presents measurements of radon and moisture infiltration from soil gases into the basement of an unoccupied research house in Madison, Wisconsin, over two full years. The basement floor and exterior walls were constructed with preservative-treated lumber and plywood. In addition to continuous radon monitoring, measurements included building air...

  17. Efficient infiltration of water in the subsurface by using point-wells: A field study

    Science.gov (United States)

    Lopik, J. V.; Schotting, R.; Raoof, A.

    2017-12-01

    The ability to infiltrate large volumes of water in the subsurface would have great value for battling flooding in urban regions. Moreover, efficient water infiltration is key to optimize underground aquifer storage and recovery (ASR), aquifer thermal energy storage (ATES), as well as construction dewatering systems. Usually, variable infiltration rates of large water quantities could have a huge hydrogeological impact in the upper part of (phreatic) aquifer systems. In urban regions, minimizing excessive groundwater table fluctuations are necessary. A newly developed method, Fast, High Volume Infiltration (FHVI), by Dutch dewatering companies can be used to enable fast injection into the shallow subsurface. Conventional infiltration methods are using injection wells that screen large parts of the aquifer depth, whereas FHVI uses a specific infiltration point (1-m well screen) in the aquifer. These infiltration points are generally thin, high permeable layers in the aquifer of approximately 0.5-2 meter thick, and are embedded by less permeable layers. Currently, much higher infiltration pressures in shallow aquifers can be achieved with FHVI (up to 1 bar) compared to conventional infiltration methods ( 0.2 bar). Despite the high infiltration pressures and high discharge rate near the FHVI-filter, the stresses on shallow groundwater levels are significantly reduced with FHVI. In order to investigate the mechanisms that enable FHVI, a field experiment is conducted in a sandy aquifer to obtain insight in the 3-D hydraulic pressure distribution and flow patterns around a FHVI-filter during infiltration. A detailed characterization of the soil profile is obtained by using soil samples and cone pressure tests with a specific hydraulic profiling tool to track the vertical variation in aquifer permeability. A tracer test with bromide and heat is conducted to investigate preferential flow paths. The experimental data show that tracking small heterogeneities in aquifers and

  18. Whole house particle removal and clean air delivery rates for in-duct and portable ventilation systems.

    Science.gov (United States)

    Macintosh, David L; Myatt, Theodore A; Ludwig, Jerry F; Baker, Brian J; Suh, Helen H; Spengler, John D

    2008-11-01

    A novel method for determining whole house particle removal and clean air delivery rates attributable to central and portable ventilation/air cleaning systems is described. The method is used to characterize total and air-cleaner-specific particle removal rates during operation of four in-duct air cleaners and two portable air-cleaning devices in a fully instrumented test home. Operation of in-duct and portable air cleaners typically increased particle removal rates over the baseline rates determined in the absence of operating a central fan or an indoor air cleaner. Removal rates of 0.3- to 0.5-microm particles ranged from 1.5 hr(-1) during operation of an in-duct, 5-in. pleated media filter to 7.2 hr(-1) for an in-duct electrostatic air cleaner in comparison to a baseline rate of 0 hr(-1) when the air handler was operating without a filter. Removal rates for total particulate matter less than 2.5 microm in aerodynamic diameter (PM2.5) mass concentrations were 0.5 hr(-1) under baseline conditions, 0.5 hr(-1) during operation of three portable ionic air cleaners, 1 hr(-1) for an in-duct 1-in. media filter, 2.4 hr(-1) for a single high-efficiency particle arrestance (HEPA) portable air cleaner, 4.6 hr(-1) for an in-duct 5-in. media filter, 4.7 hr(-1) during operation of five portable HEPA filters, 6.1 hr(-1) for a conventional in-duct electronic air cleaner, and 7.5 hr(-1) for a high efficiency in-duct electrostatic air cleaner. Corresponding whole house clean air delivery rates for PM2.5 attributable to the air cleaner independent of losses within the central ventilation system ranged from 2 m3/min for the conventional media filter to 32 m3/min for the high efficiency in-duct electrostatic device. Except for the portable ionic air cleaner, the devices considered here increased particle removal indoors over baseline deposition rates.

  19. Determination of Watershed Infiltration and Erosion Parameters from Field Rainfall Simulation Analyses

    Directory of Open Access Journals (Sweden)

    Mark E. Grismer

    2016-06-01

    Full Text Available Realistic modeling of infiltration, runoff and erosion processes from watersheds requires estimation of the effective hydraulic conductivity (Km of the hillslope soils and how it varies with soil tilth, depth and cover conditions. Field rainfall simulation (RS plot studies provide an opportunity to assess the surface soil hydraulic and erodibility conditions, but a standardized interpretation and comparison of results of this kind from a wide variety of test conditions has been difficult. Here, we develop solutions to the combined set of time-to-ponding/runoff and Green– Ampt infiltration equations to determine Km values from RS test plot results and compare them to the simpler calculation of steady rain minus runoff rates. Relating soil detachment rates to stream power, we also examine the determination of “erodibility” as the ratio thereof. Using data from over 400 RS plot studies across the Lake Tahoe Basin area that employ a wide range of rain rates across a range of soil slopes and conditions, we find that the Km values can be determined from the combined infiltration equation for ~80% of the plot data and that the laminar flow form of stream power best described a constant “erodibility” across a range of volcanic skirun soil conditions. Moreover, definition of stream power based on laminar flows obviates the need for assumption of an arbitrary Mannings “n” value and the restriction to mild slopes (<10%. The infiltration equation based Km values, though more variable, were on average equivalent to that determined from the simpler calculation of steady rain minus steady runoff rates from the RS plots. However, these Km values were much smaller than those determined from other field test methods. Finally, we compare RS plot results from use of different rainfall simulators in the basin and demonstrate that despite the varying configurations and rain intensities, similar erodibilities were determined across a range of

  20. Gamma-ray dose rate increase at rainfall events and their air-mass origins

    International Nuclear Information System (INIS)

    Iyogi, Takashi; Hisamatsu, Shun'ichi; Inaba, Jiro

    2007-01-01

    The environmental γ-ray dose rate and precipitation rates were measured at our institute, in Rokkasho, Aomori, Japan. We analyzed 425 rainfall events in which the precipitation rate was over 0.5 mm from April through November during the years 2003 to 2005. Backward trajectories for 5 d starting from 1000 m above Rokkasho at the time of the maximum dose rate in a rainfall event, were calculated by using the HYSPLIT model of the NOAA Air Resources Laboratory. The trajectories for 5 d were classified by visual inspection according to the passage areas; Pacific Ocean, Asian Continent and Japan Islands. The increase of cumulative environmental γ-ray dose during a rainfall event was plotted against the precipitation in the event, and their relationship was separately examined according to the air-mass passage area, i.e. origin of the air-mass. Our results showed that the origin of air-mass was an important factor affecting the increase of environmental γ-ray dose rate by rainfall. (author)

  1. Decontamination evaluation based on radioactivity measurement instead of air dose rate

    International Nuclear Information System (INIS)

    Shozugawa, Katsumi

    2013-01-01

    Air dose rate at 1 m above the ground comes from gamma radiations emitted from vast area ranging over several ten meters of the contaminated field from the counter. After showing the actual example of the difference between air dose rate data and Cs 137 distribution map made by using a shielded NaI-scintillation counter within and around a contaminated sinkhole (a ditch or trench) near Fukushima Daiichi Nuclear Power Plants, the author proposes to make a decontamination program according to the radioactivity distribution measurement instead of air dose rate measurement. Furthermore, he explains some problems arising from a point and plane radiation source, and also difficulties accompanied by movement of Cs 137 atoms in the soils according to the absorption characteristics of the existing minerals but these are also important to consider for performing an effective decontamination. (S. Ohno)

  2. Suppressions of Serotonin-Induced Increased Vascular Permeability and Leukocyte Infiltration by Bixa orellana Leaf Extract

    Directory of Open Access Journals (Sweden)

    Yoke Keong Yong

    2013-01-01

    Full Text Available The aim of the present study was to evaluate the anti-inflammatory activities of aqueous extract of Bixa orellana (AEBO leaves and its possible mechanisms in animal models. The anti-inflammatory activity of the extract was evaluated using serotonin-induced rat paw edema, increased peritoneal vascular permeability, and leukocyte infiltrations in an air-pouch model. Nitric oxide (NO, indicated by the sum of nitrites and nitrates, and vascular growth endothelial growth factor (VEGF were measured in paw tissues of rats to determine their involvement in the regulation of increased permeability. Pretreatments with AEBO (50 and 150 mg kg−1 prior to serotonin inductions resulted in maximum inhibitions of 56.2% of paw volume, 45.7% of Evans blue dye leakage in the peritoneal vascular permeability model, and 83.9% of leukocyte infiltration in the air-pouch model. 57.2% maximum inhibition of NO and 27% of VEGF formations in rats’ paws were observed with AEBO at the dose of 150 mg kg−1. Pharmacological screening of the extract showed significant (P<0.05 anti-inflammatory activity, indicated by the suppressions of increased vascular permeability and leukocyte infiltration. The inhibitions of these inflammatory events are probably mediated via inhibition of NO and VEGF formation and release.

  3. New procedure for sampling infiltration to assess post-fire soil water repellency

    Science.gov (United States)

    P. R. Robichaud; S. A. Lewis; L. E. Ashmun

    2008-01-01

    The Mini-disk Infiltrometer has been adapted for use as a field test of post-fire infiltration and soil water repellency. Although the Water Drop Penetration Time (WDPT) test is the common field test for soil water repellency, the Mini-disk Infiltrometer (MDI) test takes less time, is less subjective, and provides a relative infiltration rate. For each test, the porous...

  4. The effect of polyacrylamide (PAM) applications on infiltration, runoff ...

    African Journals Online (AJOL)

    user

    2011-04-11

    Apr 11, 2011 ... reduced surface runoff and soil losses, but increased infiltration rates. The effectiveness of ... Soil and water conservation is essential for sustaining food production and ...... Earth Surface Processes, 4:241-255. McIntyre DS ...

  5. Effect of ventilation rate on air cleanliness and energy consumption in operation rooms at rest.

    Science.gov (United States)

    Lee, Shih-Tseng; Liang, Ching-Chieh; Chien, Tsung-Yi; Wu, Feng-Jen; Fan, Kuang-Chung; Wan, Gwo-Hwa

    2018-02-27

    The interrelationships between ventilation rate, indoor air quality, and energy consumption in operation rooms at rest are yet to be understood. We investigate the effect of ventilation rate on indoor air quality indices and energy consumption in ORs at rest. The study investigates the air temperature, relative humidity, concentrations of carbon dioxide, particulate matter (PM), and airborne bacteria at different ventilation rates in operation rooms at rest of a medical center. The energy consumption and cost analysis of the heating, ventilating, and air conditioning (HVAC) system in the operation rooms at rest were also evaluated for all ventilation rates. No air-conditioned operation rooms had very highest PM and airborne bacterial concentrations in the operation areas. The bacterial concentration in the operation areas with 6-30 air changes per hour (ACH) was below the suggested level set by the United Kingdom (UK) for an empty operation room. A 70% of reduction in annual energy cost by reducing the ventilation rate from 30 to 6 ACH was found in the operation rooms at rest. Maintenance of operation rooms at ventilation rate of 6 ACH could save considerable amounts of energy and achieve the goal of air cleanliness.

  6. Application of Modular Modeling System to Predict Evaporation, Infiltration, Air Temperature, and Soil Moisture

    Science.gov (United States)

    Boggs, Johnny; Birgan, Latricia J.; Tsegaye, Teferi; Coleman, Tommy; Soman, Vishwas

    1997-01-01

    Models are used for numerous application including hydrology. The Modular Modeling System (MMS) is one of the few that can simulate a hydrology process. MMS was tested and used to compare infiltration, soil moisture, daily temperature, and potential and actual evaporation for the Elinsboro sandy loam soil and the Mattapex silty loam soil in the Microwave Radiometer Experiment of Soil Moisture Sensing at Beltsville Agriculture Research Test Site in Maryland. An input file for each location was created to nut the model. Graphs were plotted, and it was observed that the model gave a good representation for evaporation for both plots. In comparing the two plots, it was noted that infiltration and soil moisture tend to peak around the same time, temperature peaks in July and August and the peak evaporation was observed on September 15 and July 4 for the Elinsboro Mattapex plot respectively. MMS can be used successfully to predict hydrological processes as long as the proper input parameters are available.

  7. CONCRETE BLOCKS' ADVERSE EFFECTS ON INDOOR AIR AND RECOMMENDED SOLUTIONS

    Science.gov (United States)

    Air infiltration through highly permeable concrete blocks can allow entry of various serious indoor air pollutants. An easy approach to avoiding these pollutants is to select a less–air-permeable concrete block. Tests show that air permeability of concrete blocks can vary by a fa...

  8. Moisture removal rate for air dehumidification by triethylene glycol in a structured packed column

    International Nuclear Information System (INIS)

    Elsarrag, Esam

    2007-01-01

    In this investigation, a desiccant dehumidifier is tested for different ranges of liquid to air flow rate ratios to expand the validity range of the results. Theoretical and experimental studies of the simultaneous heat and mass transfer to evaluate the moisture removal rate are conducted. The model predictions are compared with experimental results with very good agreement. Through the experimental study, the important design variables that affect the moisture removal rate are defined and compared with previous studies. The correlation found in the literature is assessed, and the errors are reported. The parameters that are varied during the experiments included the air and liquid flow rates, the air humidity ratio, the desiccant equilibrium humidity and the packing height. It is found that the liquid flow rate has no significant effect on the moisture removal rate when the liquid to air flow ratio has exceeded the value of 2

  9. Seasonal Drivers of Dissolved Metal Transport During Infiltration of Road Runoff in an Urban Roadside Environment

    Science.gov (United States)

    Mullins, A.; Bain, D.

    2017-12-01

    Infiltration-based green infrastructure (GI) is being increasingly applied in urban areas, systems characterized by substantial legacy contamination and complicated hydrology. However, it is not clear how the application of green infrastructure changes the geochemistry of urban roadside environments. Most current research on GI focuses on small sets of chemical parameters (e.g. road salt, nitrogen and phosphorous species) over relatively short time periods, limiting comprehensive understanding of geochemical function. This work measures changes in groundwater infiltration rate and dissolved metal concentrations in two infiltration trenches in Pittsburgh, PA to evaluate function and measure dissolved metal transport from the system over time. Two distinct geochemical regimes seem to be driven by seasonality: road de-icer exchange and microbial driven summer reducing conditions. Interactions between these geochemical regimes and variability in infiltration rate control the flux of different metals, varying with metal chemistry. These findings suggest the adoption of infiltration based green infrastructure will likely create complicated patterns of legacy contamination transport to downstream receptors.

  10. Determining the ventilation and aerosol deposition rates from routine indoor-air measurements.

    Science.gov (United States)

    Halios, Christos H; Helmis, Costas G; Deligianni, Katerina; Vratolis, Sterios; Eleftheriadis, Konstantinos

    2014-01-01

    Measurement of air exchange rate provides critical information in energy and indoor-air quality studies. Continuous measurement of ventilation rates is a rather costly exercise and requires specific instrumentation. In this work, an alternative methodology is proposed and tested, where the air exchange rate is calculated by utilizing indoor and outdoor routine measurements of a common pollutant such as SO2, whereas the uncertainties induced in the calculations are analytically determined. The application of this methodology is demonstrated, for three residential microenvironments in Athens, Greece, and the results are also compared against ventilation rates calculated from differential pressure measurements. The calculated time resolved ventilation rates were applied to the mass balance equation to estimate the particle loss rate which was found to agree with literature values at an average of 0.50 h(-1). The proposed method was further evaluated by applying a mass balance numerical model for the calculation of the indoor aerosol number concentrations, using the previously calculated ventilation rate, the outdoor measured number concentrations and the particle loss rates as input values. The model results for the indoors' concentrations were found to be compared well with the experimentally measured values.

  11. Soil infiltration based on bp neural network and grey relational analysis

    Directory of Open Access Journals (Sweden)

    Wang Juan

    2013-02-01

    Full Text Available Soil infiltration is a key link of the natural water cycle process. Studies on soil permeability are conducive for water resources assessment and estimation, runoff regulation and management, soil erosion modeling, nonpoint and point source pollution of farmland, among other aspects. The unequal influence of rainfall duration, rainfall intensity, antecedent soil moisture, vegetation cover, vegetation type, and slope gradient on soil cumulative infiltration was studied under simulated rainfall and different underlying surfaces. We established a six factor-model of soil cumulative infiltration by the improved back propagation (BP-based artificial neural network algorithm with a momentum term and self-adjusting learning rate. Compared to the multiple nonlinear regression method, the stability and accuracy of the improved BP algorithm was better. Based on the improved BP model, the sensitive index of these six factors on soil cumulative infiltration was investigated. Secondly, the grey relational analysis method was used to individually study grey correlations among these six factors and soil cumulative infiltration. The results of the two methods were very similar. Rainfall duration was the most influential factor, followed by vegetation cover, vegetation type, rainfall intensity and antecedent soil moisture. The effect of slope gradient on soil cumulative infiltration was not significant.

  12. River infiltration to a subtropical alluvial aquifer inferred using multiple environmental tracers

    Science.gov (United States)

    Lamontagne, S.; Taylor, A. R.; Batlle-Aguilar, J.; Suckow, A.; Cook, P. G.; Smith, S. D.; Morgenstern, U.; Stewart, M. K.

    2015-06-01

    Chloride (Cl-), stable isotope ratios of water (δ18O and δ2H), sulfur hexafluoride (SF6), tritium (3H), carbon-14 (14C), noble gases (4He, Ne, and Ar), and hydrometry were used to characterize groundwater-surface water interactions, in particular infiltration rates, for the Lower Namoi River (New South Wales, Australia). The study period (four sampling campaigns between November 2009 and November 2011) represented the end of a decade-long drought followed by several high-flow events. The hydrometry showed that the river was generally losing to the alluvium, except when storm-derived floodwaves in the river channel generated bank recharge—discharge cycles. Using 3H/14C-derived estimates of groundwater mean residence time along the transect, infiltration rates ranged from 0.6 to 5 m yr-1. However, when using the peak transition age (a more realistic estimate of travel time in highly dispersive environments), the range in infiltration rate was larger (4-270 m yr-1). Both river water (highest δ2H, δ18O, SF6, 3H, and 14C) and an older groundwater source (lowest δ2H, δ18O, SF6, 3H, 14C, and highest 4He) were found in the riparian zone. This old groundwater end-member may represent leakage from an underlying confined aquifer (Great Artesian Basin). Environmental tracers may be used to estimate infiltration rates in this riparian environment but the presence of multiple sources of water and a high dispersion induced by frequent variations in the water table complicates their interpretation.

  13. The effect of polyacrylamide (PAM) applications on infiltration, runoff ...

    African Journals Online (AJOL)

    . Anionic polyacrylamide (PAM) application to soils is an effective soil conservation practice for reducing runoff and soil losses caused by erosion. It also increases the infiltration rate of soils. The objective of this study was conducted to ...

  14. TiO{sub 2} based photo-catalysts prepared by chemical vapor infiltration (CVI) on micro-fibrous substrates; Photocatalyseurs a base de TiO{sub 2} prepares par infiltration chimique en phase vapeur (CVI) sur supports microfibreux

    Energy Technology Data Exchange (ETDEWEB)

    Sarantopoulos, Ch

    2007-10-15

    This thesis deals with micro-fibrous glass substrates functionalized with TiO{sub 2}. The oxide is deposited as a thin film onto the micro fibres by chemical vapour infiltration (CVI), yielding a photo-catalytic material usable for cleaning polluted air. We studied the relation between the structure of the material and its photo-catalytic efficiency. TiO{sub 2} thin films were prepared at low pressure, in a hot-wall CVD reactor, using Ti(O-iPr){sub 4} as a precursor. They were characterized by XRD, SEM, EDX, XPS and BET, and by recording the kinetics of decomposition of varied pollutants in solution (orange G, malic acid, imazapyr) and in air (toluene). The conditions favoring the growth of porous films through a columnar growth mode were established by MOCVD-depositing TiO{sub 2} thin films on flat substrates. The subsequent works with micro fibrous thick substrates showed the uniformity of infiltration to be the main factor governing the photo-catalytic efficiency. Operating parameters that optimize infiltration do not yield columnar growth mode. A compromise is necessary. Our photo-catalysts are showing high efficiency comparable, if not higher, to those actually commercialized. These promising results are opening real perspectives for the proposed process. (author)

  15. A simulation of rainfall infiltration based on two-phase flow

    Science.gov (United States)

    Wang, Jun; Xi, Niannian; Liu, Gang; Hao, Shuang

    2016-04-01

    Rainfall infiltration in slope usually is one of major reasons cause landslide, which involves multiphase flow coupling with soil, water and gas. In order to study the mechanism of landslide caused by rainfall infiltration, a simulation of rainfall infiltration of DaPing slope, which locates in the Three Gorges Region of China, is presented based on the numerical solution of governing equations of two-phase flow in this paper. The results of this research suggest that there are two sections can be divided in the surface of slope, one is inflow area and the other is overflow area, according to where it is infiltration and discharge. The general inflow area is on the upside of slope, while the overflow area is on the underside. The middle section of slope is on a fluctuant position between inflow and overflow area, which is dramatically affected by the water content inside of slope. Moreover, the average rate of infiltration is more stable in both inflow and overflow area, whose numerical value is depend on the geometry and transmission characteristics of slope. And the factors of rainfall characteristics, surface flow and temperature have little effect on them. Furthermore, in the inflow area, when rainfall intensity is higher than infiltration the rain on the surface of slope will run off, otherwise water and gas will completely infiltrate through soil. The situation is different in the overflow area whose overland flow condition is depended on whether it is saturated or not inside of slope. When it is saturated in the slope, there is no infiltration in the overflow area. But when it is unsaturated, the infiltration intensity will equal to rainfall intensity. In a summary, the difference from inflow and overflow area is the evidence that the landslide may likely to happen on the slope of overflow area when it comes to a rainfall. It is disadvantageous for slope stability when transmitting the pressure of saturated water weight at the top of slope through the pore

  16. TiO2 based photo-catalysts prepared by chemical vapor infiltration (CVI) on micro-fibrous substrates

    International Nuclear Information System (INIS)

    Sarantopoulos, Ch.

    2007-10-01

    This thesis deals with micro-fibrous glass substrates functionalized with TiO 2 . The oxide is deposited as a thin film onto the micro fibres by chemical vapour infiltration (CVI), yielding a photo-catalytic material usable for cleaning polluted air. We studied the relation between the structure of the material and its photo-catalytic efficiency. TiO 2 thin films were prepared at low pressure, in a hot-wall CVD reactor, using Ti(O-iPr) 4 as a precursor. They were characterized by XRD, SEM, EDX, XPS and BET, and by recording the kinetics of decomposition of varied pollutants in solution (orange G, malic acid, imazapyr) and in air (toluene). The conditions favoring the growth of porous films through a columnar growth mode were established by MOCVD-depositing TiO 2 thin films on flat substrates. The subsequent works with micro fibrous thick substrates showed the uniformity of infiltration to be the main factor governing the photo-catalytic efficiency. Operating parameters that optimize infiltration do not yield columnar growth mode. A compromise is necessary. Our photo-catalysts are showing high efficiency comparable, if not higher, to those actually commercialized. These promising results are opening real perspectives for the proposed process. (author)

  17. Evaluating the Infiltration Performance of Eight Dutch Permeable Pavements Using a New Full-Scale Infiltration Testing Method

    Directory of Open Access Journals (Sweden)

    Floris Boogaard

    2014-07-01

    Full Text Available Permeable pavements are a type of sustainable urban drainage system (SUDS technique that are used around the world to infiltrate and treat urban stormwater runoff and to minimize runoff volumes. Urban stormwater runoff contains significant concentrations of suspended sediments that can cause clogging and reduce the infiltration capacity and effectiveness of permeable pavements. It is important for stormwater managers to be able to determine when the level of clogging has reached an unacceptable level, so that they can schedule maintenance or replacement activities as required. Newly-installed permeable pavements in the Netherlands must demonstrate a minimum infiltration capacity of 194 mm/h (540 l/s/ha. Other commonly used permeable pavement guidelines in the Netherlands recommend that maintenance is undertaken on permeable pavements when the infiltration falls below 0.50 m/d (20.8 mm/h. This study used a newly-developed, full-scale infiltration test procedure to evaluate the infiltration performance of eight permeable pavements in five municipalities that had been in service for over seven years in the Netherlands. The determined infiltration capacities vary between 29 and 342 mm/h. Two of the eight pavements show an infiltration capacity higher than 194 mm/h, and all infiltration capacities are higher than 20.8 mm/h. According to the guidelines, this suggests that none of the pavements tested in this study would require immediate maintenance.

  18. Catch crops impact on soil water infiltration in vineyards

    Science.gov (United States)

    Cerdà, Artemi; Bagarello, Vincenzo; Iovino, Massimo; Ferro, Vito; Keesstra, Saskia; Rodrigo-Comino, Jesús; García Diaz, Andrés; di Prima, Simone

    2017-04-01

    Infiltration is the key component of the hydrological cycle (Cerdà, 1999; Bagarello et al.,, 2014; Zema et al., 2016). Infiltration determines the partitioning of rainfall into runoff and subsurface flow (Cerdà, 1996; Bagarello et al., 2006; Wang et al., 2016). In the Mediterranean, agriculture resulted in the degradation of the soil structure, reduction of the organic matter and increase in the soil losses (Cerdà et al., 2009; Laudicina et al., 2015; Iovino et al., 2016; Willaarts et al., 2016). There is an urgent need to restore the agriculture soils to avoid floods, reduce the carbon emissions and avoid reservoir siltation (Aksakal et al., 2016; Ben Slimane et al., 2016; Yagüe et al., 2016). Catch Crops are widespread used due to their impact on the soil fertility (Mwango et al., 2016; Nishigaki et al., 2016 ; Nawaz et al., 2016). Catch crops also increase the amount of organic matter but little is known about the effect on soil infiltration. Two paired plots were selected in Les Alcusses (Moixent municipality) in Eastern Iberian Peninsula to compare the infiltration rates between a 8-years catch crop (Vicia sp) with a control (plough) soil. The measurements were carried out by means of ring infiltrometer in August 2014 and December 2014 under dry and wet conditions (Cerdà, 2001; Di Prima et al., 2016). The results show that the steady-state infiltration rates were 1.8 higher during the summer period, and that the catch crops did not increase the infiltration rates. Acknowledgements The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement n 603498 (RECARE project) and the CGL2013- 47862-C2-1-R and CGL2016-75178-C2-2-R national research projects. References Aksakal, E. L., Sari, S., & Angin, I. (2016). Effects of vermicompost application on soil aggregation and certain physical properties. Land Degradation and Development, 27(4), 983-995. doi:10.1002/ldr.2350

  19. The impact of subterranean termite activity on water infiltration and topsoil properties in Burkina Faso

    NARCIS (Netherlands)

    Mettrop, I.S.; Cammeraat, L.H.; Verbeeten, E.

    2013-01-01

    Few quantitative experimental studies have been carried out on the influence of subterranean termite activity on the water infiltration capacity of crusted soils in the semi-arid Sahelian region. These studies found increased infiltration rates on soils that were affected by foraging galleries of

  20. Assessment of ventilation efficiency for the study of indoor air quality; Appreciation de l'efficacite de la ventilation pour l'etude de la qualite de l'air interieur

    Energy Technology Data Exchange (ETDEWEB)

    Akoua, A.A.

    2004-10-15

    An efficient ventilation system provides a good indoor air quality by eliminating air pollutants and ensuring a satisfactory air renewal. Unlike most research works that deal with test cells with controlled boundary conditions, our study focuses on ventilation efficiency in a real environment. In situ experiments are performed and provide the boundary conditions necessary for CFD (Computational Fluid Dynamics) computations. Using CFD for predicting indoor air quality in a real environment is thus analyzed. The influence of permeability on numerical predictions quality is shown. Unfortunately, it is difficult to quantify accurately the air leakages and their airflow rates. Our study proposes a simplified model that includes air infiltration rates in the CFD computations, and that yields satisfactory results. A critical analysis of ventilation efficiency indices is then performed. It is shown that it is currently impossible to evaluate the air change efficiency ( a e ) in an occupied zone. Concerning the air pollutants removal effectiveness, it is shown that the usual index C e is not suited to ventilation systems with variable airflow rates. For such cases, a new formulation of this index is given. The ratio between the airflow rate and the nominal airflow rate of the ventilation system is also taken into consideration. A coupled analysis of this new index and of this airflow rate ratio enables us to assess the air pollutants removal effectiveness while considering the energetic cost of ventilation. We finally show that there is no universal index. The choice of the index depends on the pollutant, on the pollutant concentration, and on the airflow rate. A tool of decision-making aid is thus proposed in order to evaluate the air pollutants removal effectiveness for various ventilation systems. This tool is flexible and rather simple to use. (author)

  1. Experimental verification of air flow rate measurement for representative isokinetic air sampling in ventilation stacks

    International Nuclear Information System (INIS)

    Okruhlica, P.; Mrtvy, M.; Kopecky, Z.

    2009-01-01

    Nuclear facilities are obliged to monitor their discharge's influence on environment. Main monitored factions in NPP's ventilation stacks are usually noble gasses, particulates and iodine. These factions are monitored in air sampled from ventilation stack by means of sampling rosette and bypass followed with on-line measuring monitors and balance sampling devices with laboratory evaluations. Correct air flow rate measurement and representative iso-kinetic air sampling system is essential for physical correct and metrological accurate evaluation of discharge influence on environment. Pairs of measuring sensors (Anemometer, pressure gauge, thermometer and humidity meter) are symmetrically placed in horizontal projection of stack on positions based on measured air flow velocity distribution characteristic, Analogically diameter of sampling rosette nozzles and their placement in the middle of 6 - 7 annuluses are calculated for assurance of representative iso-kinetic sampling. (authors)

  2. Experimental verification of air flow rate measurement for representative isokinetic air sampling in ventilation stacks

    International Nuclear Information System (INIS)

    Okruhlica, P.; Mrtvy, M.; Kopecky, Z.

    2008-01-01

    Nuclear facilities are obliged to monitor their discharge's influence on environment. Main monitored factions in NPP's ventilation stacks are usually noble gasses, particulates and iodine. These factions are monitored in air sampled from ventilation stack by means of sampling rosette and bypass followed with on-line measuring monitors and balance sampling devices with laboratory evaluations. Correct air flow rate measurement and representative iso-kinetic air sampling system is essential for physical correct and metrological accurate evaluation of discharge influence on environment. Pairs of measuring sensors (Anemometer, pressure gauge, thermometer and humidity meter) are symmetrically placed in horizontal projection of stack on positions based on measured air flow velocity distribution characteristic, Analogically diameter of sampling rosette nozzles and their placement in the middle of 6- 7 annuluses are calculated for assurance of representative iso-kinetic sampling. (authors)

  3. Influence of surficial soil and bedrock on indoor radon in New York State homes. Task 2, Subtask 2 of an investigation of infiltration and indoor air quality in New York State homes

    International Nuclear Information System (INIS)

    Kunz, C.

    1989-10-01

    Radon can enter a building from soil and bedrock through cracks or openings in the basement. Extrapolation from data obtained from studies of miners exposed to high concentrations of radon and other carcinogens over long periods indicates that radon gas in the home poses an increased risk of lung cancer. The project was initiated to determine the characteristics of soil and bedrock that contribute to the availability of radon for infiltration into the home, and the feasibility of using soil characteristics in mapping areas at higher risk for above-average indoor radon in New York State. After conducting soil surveys across the State, the researchers choose four areas for further study. Fifteen homes in each area were tested for indoor air concentrations of radon, air infiltration into the home, radon concentrations in the soil, and the permeability of the soil for gas flow. The researchers concluded that these parameters could be combined to obtain a Radon Index Number to predict mean indoor radon levels for a given area with similar soil geology. However, this measure has a limited ability to predict indoor radon levels for a particular home due to variations in construction as well as differences in soil and bedrock

  4. Emission Rates of Multiple Air Pollutants Generated from Chinese Residential Cooking.

    Science.gov (United States)

    Chen, Chen; Zhao, Yuejing; Zhao, Bin

    2018-02-06

    Household air pollution generated from cooking is severe, especially for Chinese-style cooking. We measured the emission rates of multiple air pollutants including fine particles (PM 2.5 ), ultrafine particles (UFPs), and volatile organic compounds (VOCs, including formaldehyde, benzene, and toluene) that were generated from typical Chinese cooking in a residential kitchen. The experiment was designed through five-factor and five-level orthogonal testing. The five key factors were cooking method, ingredient weight, type of meat, type of oil, and meat/vegetable ratio. The measured emission rates (mean value ± standard deviation) of PM 2.5 , UFPs, formaldehyde, total volatile organic compounds (TVOCs), benzene, and toluene were 2.056 ± 3.034 mg/min, 9.102 ± 6.909 × 10 12 #/min, 1.273 ± 0.736 mg/min, 1.349 ± 1.376 mg/min, 0.074 ± 0.039 mg/min, and 0.004 ± 0.004 mg/min. Cooking method was the most influencing factor for the emission rates of PM 2.5 , UFPs, formaldehyde, TVOCs, and benzene but not for toluene. Meanwhile, the emission rate of PM 2.5 was also significantly influenced by ingredient weight, type of meat, and meat/vegetable ratio. Exhausting the range hood decreased the emission rates by approximately 58%, with a corresponding air change rate of 21.38/h for the kitchen room.

  5. Improved air ventilation rate estimation based on a statistical model

    International Nuclear Information System (INIS)

    Brabec, M.; Jilek, K.

    2004-01-01

    A new approach to air ventilation rate estimation from CO measurement data is presented. The approach is based on a state-space dynamic statistical model, allowing for quick and efficient estimation. Underlying computations are based on Kalman filtering, whose practical software implementation is rather easy. The key property is the flexibility of the model, allowing various artificial regimens of CO level manipulation to be treated. The model is semi-parametric in nature and can efficiently handle time-varying ventilation rate. This is a major advantage, compared to some of the methods which are currently in practical use. After a formal introduction of the statistical model, its performance is demonstrated on real data from routine measurements. It is shown how the approach can be utilized in a more complex situation of major practical relevance, when time-varying air ventilation rate and radon entry rate are to be estimated simultaneously from concurrent radon and CO measurements

  6. Dosimetric Effects of Air Pockets Around High-Dose Rate Brachytherapy Vaginal Cylinders

    International Nuclear Information System (INIS)

    Richardson, Susan; Palaniswaamy, Geethpriya; Grigsby, Perry W.

    2010-01-01

    Purpose: Most physicians use a single-channel vaginal cylinder for postoperative endometrial cancer brachytherapy. Recent published data have identified air pockets between the vaginal cylinders and the vaginal mucosa. The purpose of this research was to evaluate the incidence, size, and dosimetric effects of these air pockets. Methods and Materials: 25 patients receiving postoperative vaginal cuff brachytherapy with a high-dose rate vaginal cylinders were enrolled in this prospective data collection study. Patients were treated with 6 fractions of 200 to 400 cGy per fraction prescribed at 5 mm depth. Computed tomography simulation for brachytherapy treatment planning was performed for each fraction. The quantity, volume, and dosimetric impact of the air pockets surrounding the cylinder were quantified. Results: In 25 patients, a total of 90 air pockets were present in 150 procedures (60%). Five patients had no air pockets present during any of their treatments. The average number of air pockets per patient was 3.6, with the average total air pocket volume being 0.34 cm 3 (range, 0.01-1.32 cm 3 ). The average dose reduction to the vaginal mucosa at the air pocket was 27% (range, 9-58%). Ten patients had no air pockets on their first fraction but air pockets occurred in subsequent fractions. Conclusion: Air pockets between high-dose rate vaginal cylinder applicators and the vaginal mucosa are present in the majority of fractions of therapy, and their presence varies from patient to patient and fraction to fraction. The existence of air pockets results in reduced radiation dose to the vaginal mucosa.

  7. Investigation of effect of air flow rate on Zircaloy-4 oxidation kinetics and breakaway phenomenon in air at 850 .deg. C

    International Nuclear Information System (INIS)

    Maeng, Yunhwan; Lee, Jaeyoung; Park, Sanggil

    2016-01-01

    This paper analyzed an effect of flow rate on oxidation kinetics of Zircaloy-4 in air at 850 .deg. C. In case of the oxidation of Zircaloy-4 in air at 850 .deg. C, acceleration of oxidation kinetics from parabolic to linear (breakaway phenomenon) occurs. Oxidation and breakaway kinetics of the Zircaloy-4 in air was experimentally studied by changing a flow rate of argon/air mixture. Tests were conducted at 850 .deg. C under constant ratio of argon and air. The effects of flow rate on the oxidation and breakaway kinetics was observed. This paper is based on a revised and considerably extended presentation given at the 21 st International Quench Workshop. The effects of flow conditions on the oxidation kinetics of Zircaloy-4 samples were explained with residence time and percent flow efficiency. In addition, several issues were observed from this study, interdiffusion at breakaway and deformation of oxide structure by breakaway phenomenon

  8. Behaviour of chromium(VI) in stormwater soil infiltration systems

    DEFF Research Database (Denmark)

    Cederkvist, Karin; Ingvertsen, Simon T.; Jensen, Marina B.

    2013-01-01

    mm in 2 h) and extreme (100 mm in 3 h) rain events. The objectives were to understand the behaviour of the anionic and toxic Cr(VI) in soil at neutral pH and to asses treatment efficiency towards Cr(VI). During normal rain events Cr(VI) was largely retained (more than 50, even though pH was neutral......The ability of stormwater infiltration systems to retain Cr(VI) was tested by applying a synthetic stormwater runoff solution with a neutral pH and high Cr(VI) concentrations to four intact soil columns excavated from two roadside infiltration swales in Germany. Inlet flow rates mimicked normal (10......, while under extreme rain events approximately 20% of Cr(VI) was retained. In both cases effluent concentrations of Cr(VI) would exceed the threshold value of 3.4 mu g/L if the infiltrated water were introduced to freshwater environments. More knowledge on the composition of the stormwater runoff...

  9. Performance and Structural Evolution of Nano-Scale Infiltrated Solid Oxide Fuel Cell Cathodes

    Science.gov (United States)

    Call, Ann Virginia

    low pO2. The cells were subjected to life testing at temperatures between 650°C and 800°C for as long as 1500 h. EIS measurements, carried out periodically during the life tests, were done in air at 600°C, a typical expected intermediate-temperature SOFC operating temperature. These were accelerated tests because the aging temperatures > 600ºC should accelerate most degradation processes such as nano-particle coarsening. Long-term RP versus time data was fitted to a combined surface resistance and coarsening kinetics model, and a t0.25 power law coarsening model was found to provide the best fits to the data, suggesting that surface diffusion is the dominant mass transport pathway in SSC-GDC infiltrated cathodes. That is, cathode degradation was due primarily to the coarsening-induced decrease in active SSC surface area. Scanning electron microscopy (SEM) performed after electrochemical life testing confirmed the extent of coarsening of the SSC nanoparticles. The model is used to make predictions regarding long-term stability of infiltrated SSC electrodes, and is also compared with prior results on a similar perovskite MIEC electrode, LSCF. An important new finding is that increasing infiltration loadings yields a marked decrease in the long term degradation rate. Predictions based on accelerated life tests found the lowest possible operating temperature while achieving a degradation rate of 0.5% per kh is 595°C, corresponding to an initial particle size of 40 nm.

  10. Corrections to air kerma rate measurements of 125I brachytherapy sources to free space conditions

    International Nuclear Information System (INIS)

    Shipley, D.R.; Duane, S.

    1994-05-01

    Air kerma rate measurements have been made between 40 cm and 100 cm from one of a set of 125 I reference sources within the facilities of Amersham International plc. Monte Carlo techniques have been used to calculate the air kerma rate components over the same range of distances from this source. After comparing the calculated data with measurements, the compliance of the data with the inverse square law was investigated, and corrections were derived to obtain the air kerma rate at 1 m in free space from each source. Simulations of the experimental setup with an isotropic monoenergetic point source close to the effective energy of 125 I were found to reproduce the air kerma rate measurements reasonably accurately, and indicated that the contribution due to scattered photons was significant. The overall correction (which is defined as the product of individual corrections for chamber size effect, air attenuation and radiation scatter) required to the inverse square law to obtain the air kerma rate at 1 m in free space was found to be 0.981, 0.984 and 0.980, respectively, for air kerma rate measurements at 40 cm, 60 cm and 100 cm from the 125 I reference source. The total uncertainty in these corrections was estimated to be 0.88% at the 1σ level. (author)

  11. Infiltration control for low-level radioactive solid waste disposal areas: an assessment

    International Nuclear Information System (INIS)

    Arora, H.S.

    1980-11-01

    The primary mode of radionuclide transport from shallow land-disposal sites for low-level wastes can be traced to infiltration of precipitation. This report examines the factors that affect surface water entry and movement in the ground and assesses available infiltration-control technology for solid-waste-disposal sites in the humid eastern portion of the United States. A survey of the literature suggests that a variety of flexible and rigid liner systems are available as barriers for the stored waste and would be effective in preventing water infiltration. Installation of near-surface seals of bentonite clay admixed with dispersive chemicals seem to offer the required durability and low permeability at a reasonable cost. The infiltration rate in a bentonite-sealed area may be further retarded by the application of dispersive chemicals that can be easily admixed with the surface soil. Because the effectiveness of a dispersive chemical for infiltration reduction is influenced by the physico-chemical properties of the soil, appropriate laboratory tests should be conducted prior to field application

  12. Depth of Intestinal Wall Infiltration and Clinical Presentation of Deep Infiltrating Endometriosis: Evaluation of 553 Consecutive Cases.

    Science.gov (United States)

    Rossini, Roberto; Lisi, Giorgio; Pesci, Anna; Ceccaroni, Marcello; Zamboni, Giuseppe; Gentile, Irene; Rettore, Lorenzo; Ruffo, Giacomo

    2018-02-01

    Intestinal involvement in endometriosis was first described by Sampson in 1922. The reported incidence ranges between 3% and 37% in patients diagnosed with endometriosis. In literature, there are few studies that correlate the severity of endometriosis (in terms of intestinal infiltration) and its clinical presentation. The aim of this study was to review the correlation between the severity of symptoms, the depth of intestinal wall infiltration, and lymph node involvement in our tertiary referral center. We retrospectively analyzed 553 patients who had undergone intestinal resection for deep infiltrating endometriosis at our institution (Sacro Cuore Negrar Hospital) between 2004 and 2009. Based on intestinal wall infiltration, we divided patients into three groups (Group A: intestinal infiltration that reaches the muscle layer, Group B: infiltration to the submucosa, and Group C: endometriosis reaches the mucosa). Symptoms, intestinal stenosis, and positive lymph nodes were compared in the three groups with the chi-square test. No statistical correlation was found between symptoms and the intestinal wall infiltrations. The three groups were also compared on the basis of positive visceral lymph nodes and we did find a statistical difference (P = .05) in the lymph node count in the two main groups. There seems to be no statistically significant difference in symptoms between patients with different degrees of infiltration. Although visceral lymph node involvement has been occasionally described in literature, we found that it is related to submucosal infiltration.

  13. Testing the goodness of fit of selected infiltration models on soils with different land use histories

    International Nuclear Information System (INIS)

    Mbagwu, J.S.C.

    1993-10-01

    Six infiltration models, some obtained by reformulating the fitting parameters of the classical Kostiakov (1932) and Philip (1957) equations, were investigated for their ability to describe water infiltration into highly permeable sandy soils from the Nsukka plains of SE Nigeria. The models were Kostiakov, Modified Kostiakov (A), Modified Kostiakov (B), Philip, Modified Philip (A) and Modified Philip (B). Infiltration data were obtained from double ring infiltrometers on field plots established on a Knadic Paleustult (Nkpologu series) to investigate the effects of land use on soil properties and maize yield. The treatments were; (i) tilled-mulched (TM), (ii) tilled-unmulched (TU), (iii) untilled-mulched (UM), (iv) untilled-unmulched (UU) and (v) continuous pasture (CP). Cumulative infiltration was highest on the TM and lowest on the CP plots. All estimated model parameters obtained by the best fit of measured data differed significantly among the treatments. Based on the magnitude of R 2 values, the Kostiakov, Modified Kostiakov (A), Philip and Modified Philip (A) models provided best predictions of cumulative infiltration as a function of time. Comparing experimental with model-predicted cumulative infiltration showed, however, that on all treatments the values predicted by the classical Kostiakov, Philip and Modified Philip (A) models deviated most from experimental data. The other models produced values that agreed very well with measured data. Considering the eases of determining the fitting parameters it is proposed that on soils with high infiltration rates, either Modified Kostiakov model (I = Kt a + Ict) or Modified Philip model (I St 1/2 + Ict), (where I is cumulative infiltration, K, the time coefficient, t, time elapsed, 'a' the time exponent, Ic the equilibrium infiltration rate and S, the soil water sorptivity), be used for routine characterization of the infiltration process. (author). 33 refs, 3 figs 6 tabs

  14. In-situ infiltration performance of different permeable pavements in a employee used parking lot--A four-year study.

    Science.gov (United States)

    Kumar, Kuldip; Kozak, Joseph; Hundal, Lakhwinder; Cox, Albert; Zhang, Heng; Granato, Thomas

    2016-02-01

    Permeable pavements are being adopted as a green solution in many parts of the world to manage urban stormwater quantity and quality. This paper reports on the measured in-situ infiltration performance over a four-year period since construction and use of three permeable parking sections (permeable pavers, permeable concrete and permeable asphalt) of an employee car parking lot. There was only a marginal decline in infiltration rates of all three pavements after one year of use. However, between years two to four, the infiltration rates declined significantly due to clogging of pores either by dry deposition of particles and/or shear stress of vehicles driving and degrading the permeable surfaces; during the last two years, a greater decline was also observed in driving areas of the parking lots compared to parking slots, where minimal wear and tear are expected. Maintenance strategies were employed to reclaim some of the lost infiltration rate of the permeable pavements to limited success. Despite this decline, the infiltration rates were still four to five times higher than average rainstorm intensity in the region. Thus, these permeable pavement parking lots may have significant ecological importance due to their ability to infiltrate rainwater quickly, reduce the runoff in the catchment area, and also dampen runoff peak flows that could otherwise enter the collection system for treatment in a combined sewer area. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Effect of air infiltration in the reactor refrigerant on the radiation measurement systems of gaseous effluents treatment

    International Nuclear Information System (INIS)

    Zorrilla, S.; Padilla, I.

    1991-01-01

    The system of treatment of gassy effluents of the CLV, well-known as the off-gas this gifted one in turn of a mensuration system and registration (monitoring) that consists of diverse established radiation monitors in the discharge point to the atmosphere and in other intermediate points of the process. The purpose of the monitoring system is to maintain continually informed to the operators about the effectiveness of the treatment system, to take registrations of the total quantity of liberated radioactive materials and to give warning by means of an alarm system of any abnormal situation that could end in an approach to the limits marked by the technical specifications. In September 1989 an event happened in the one that the high alarms corresponding to the post-treatment of the off-gas were activated. For this situation the personnel proceeded to diminish the power of the reactor to be able to investigate the causes that gave place to the event. It was observed that the alarms of the monitor were activated by significant infiltrations of air in the primary circuit of the refrigerant, for what it was proceeded to enlarge the scales of the implied monitor or to reduce the sensibility of their readings

  16. Groundwater infiltration, surface water inflow and sewerage exfiltration considering hydrodynamic conditions in sewer systems.

    Science.gov (United States)

    Karpf, Christian; Hoeft, Stefan; Scheffer, Claudia; Fuchs, Lothar; Krebs, Peter

    2011-01-01

    Sewer systems are closely interlinked with groundwater and surface water. Due to leaks and regular openings in the sewer system (e.g. combined sewer overflow structures with sometimes reverse pressure conditions), groundwater infiltration and surface water inflow as well as exfiltration of sewage take place and cannot be avoided. In the paper a new hydrodynamic sewer network modelling approach will be presented, which includes--besides precipitation--hydrographs of groundwater and surface water as essential boundary conditions. The concept of the modelling approach and the models to describe the infiltration, inflow and exfiltration fluxes are described. The model application to the sewerage system of the City of Dresden during a flood event with complex conditions shows that the processes of infiltration, exfiltration and surface water inflows can be described with a higher reliability and accuracy, showing that surface water inflow causes a pronounced system reaction. Further, according to the simulation results, a high sensitivity of exfiltration rates on the in-sewer water levels and a relatively low influence of the dynamic conditions on the infiltration rates were found.

  17. Nutrient transport and transformation beneath an infiltration basin

    Science.gov (United States)

    Sumner, D.M.; Rolston, D.E.; Bradner, L.A.

    1998-01-01

    Field experiments were conducted to examine nutrient transport and transformation beneath an infiltration basin used for the disposal of treated wastewater. Removal of nitrogen from infiltrating water by denitrification was negligible beneath the basin, probably because of subsurface aeration as a result of daily interruptions in basin loading. Retention of organic nitrogen in the upper 4.6 m of the unsaturated zone (water table depth of approximately 11 m) during basin loading resulted in concentrations of nitrate as much as 10 times that of the applied treated wastewater, following basin 'rest' periods of several weeks, which allowed time for mineralization and nitrification. Approximately 90% of the phosphorus in treated wastewater was removed within the upper 4.6 m of the subsurface, primarily by adsorption reactions, with abundant iron and aluminum oxyhydroxides occurring as soil coatings. A reduction in the flow rate of infiltrating water arriving at the water table may explain the accumulation of relatively coarse (>0.45 ??m), organic forms of nitrogen and phosphorus slightly below the water table. Mineralization and nitrification reactions at this second location of organic nitrogen accumulation contributed to concentrations of nitrate as much as three times that of the applied treated wastewater. Phosphorus, which accumulated below the water table, was immobilized by adsorption or precipitation reactions during basin rest periods.Field experiments were conducted to examine nutrient transport and transformation beneath an infiltration basin used for the disposal of treated wastewater. Removal of nitrogen from infiltrating water by denitrification was negligible beneath the basin, probably because of subsurface aeration as a result of daily interruptions in basin loading. Retention of organic nitrogen in the upper 4.6 m of the unsaturated zone (water table depth of approximately 11 m) during basin loading resulted in concentrations of nitrate as much as 10

  18. An analytical model for cumulative infiltration into a dual-permeability media

    Science.gov (United States)

    Peyrard, Xavier; Lassabatere, Laurent; Angulo-Jaramillo, Rafael; Simunek, Jiri

    2010-05-01

    Modeling of water infiltration into the vadose zone is important for better understanding of movement of water-transported contaminants. There is a great need to take into account the soil heterogeneity and, in particular, the presence of macropores or cracks that could generate preferential flow. Several mathematical models have been proposed to describe unsaturated flow through heterogeneous soils. The dual-permeability model assumes that flow is governed by Richards equation in both porous regions (matrix and fractures). Water can be exchanged between the two regions following a first-order rate law. A previous study showed that the influence of the hydraulic conductivity of the matrix/macropore interface had a little influence on cumulative infiltration at the soil surface. As a result, one could consider the surface infiltration for a specific case of no water exchange between the fracture and matrix regions (a case of zero interfacial hydraulic conductivity). In such a case, water infiltration can be considered to be the sum of the cumulative infiltrations into the matrix and the fractures. On the basis of analytical models for each sub domain (matrix and fractures), an analytical model is proposed for the entire dual-porosity system. A sensitivity analysis is performed to characterize the influence of several factors, such as the saturated hydraulic conductivity ratio, the water pressure scale parameter ratio, and the saturated volumetric water content scale ratio, on the total cumulative infiltration. Such an analysis greatly helps in quantifying the impact of macroporosity and fractures on water infiltration, which can be of great interest for hydrological models.

  19. Optimization of Design of Aquifer Storage and Recovery System (ASTR) for Enhanced Infiltration Rate with Reduced Cost at the Coastal Aquifers of South-Western Bangladesh

    Science.gov (United States)

    Nawrin, N.; Ahmed, K. M.; Rahman, M. M.

    2016-12-01

    Increasing salinity of natural drinking water sources has been reported as one of the many problems that affect low-income countries. Safe potable water sources in coastal Bangladesh have become contaminated by varying degrees of salinity due to saltwater intrusion, cyclone and storm surges and increased shrimp and crab farming along the coastal areas. This crisis is also exacerbated owing to climate change. The problem of salinity can have serious implications to public health. Here Managed Aquifer Recharge (MAR) has been ascertained as a better solution to overcome the fresh water shortage in the coastal belt of Bangladesh in terms of groundwater quality improvement and supply fresh water even during the dry period. 19 MAR systems have been built and tested in the area for providing community water supply by way of creating freshwater buffer zone in the brackish aquifers through artificial recharge of pond or rooftop rainwater. These existing ASTR schemes consist of sand filtration tank with 4 to 6 large diameter infiltration wells filled with sorted gravel. These larger diameter recharge wells make the construction and maintenance expensive and little difficult for the rural communities. Therefore, modification of design is required for enhancing infiltration rates with reduced costs. As the design of the existing MAR system have confronted some problems, the details of design, construction and performance have been studied from previous investigations and a new modified ASTR scheme has been demonstrated to amplify the infiltration rate along with monitoring scheme. Smaller 4 inch diameter empty recharge wells and PVC screen have been used in the newly developed design. Daily infiltration rate has been increased to 8 to 10 m3/d compared to 4 to 6 m3/d in the old design. Three layered sand filtration tank has been prepared by modification of an abandoned PSF. Time needed for lowering EC to acceptable limits has been found to be significantly lower than the pre

  20. Warmed local anesthetic reduces pain of infiltration.

    Science.gov (United States)

    Fialkov, J A; McDougall, E P

    1996-01-01

    The effect of warming local anesthetic on the amount of pain experienced during local infiltration was tested by comparing equal volumes of 40 degrees C- and 21 degrees C-infiltrates in each of 26 subjects. Six subjects were patients undergoing excision of two benign asymptomatic nevi in separate locations, and 20 subjects were healthy adult volunteers who were injected in bilateral antebrachial sites. The warmed and room temperature solutions were randomized to each side, so that each subject received both temperature injections in random order. All subjects and the injector were blinded. The rate of injection was time-controlled (0.05 ml/sec). Following both injections, subjects were asked to rate the pain experienced at each site. In addition, the subject was asked if there was no difference, a slight difference, or a substantial difference between the two sites. A two-tailed paired t-test was used to analyze the mean difference in pain scores for all subjects. Paired analysis of the pain scores for each subject eliminated intersubject variance of pain tolerance. The mean difference in pain score between the room temperature and warmed solutions was +1.5 (p < 0.0001). Of the 21 subjects (81%) who found the warmed solution less painful, 11 (52%) found the difference to be significant, while 10 (48%) found the difference to be slight. Two subjects (8%) found no difference between the two, while 3 subjects (11%) found the colder solution slightly less painful. We conclude that warming local anesthetic to 40 degrees C prior to subcutaneous injection is a simple, inexpensive means of reducing the pain of local infiltration.

  1. A simplified CT-guided approach for greater occipital nerve infiltration in the management of occipital neuralgia.

    Science.gov (United States)

    Kastler, Adrian; Onana, Yannick; Comte, Alexandre; Attyé, Arnaud; Lajoie, Jean-Louis; Kastler, Bruno

    2015-08-01

    To evaluate the efficacy of a simplified CT-guided greater occipital nerve (GON) infiltration approach in the management of occipital neuralgia (ON). Local IRB approval was obtained and written informed consent was waived. Thirty three patients suffering from severe refractory ON who underwent a total of 37 CT-guided GON infiltrations were included between 2012 and 2014. GON infiltration was performed at the first bend of the GON, between the inferior obliqus capitis and semispinalis capitis muscles with local anaesthetics and cortivazol. Pain was evaluated via VAS scores. Clinical success was defined by pain relief greater than or equal to 50 % lasting for at least 3 months. The pre-procedure mean pain score was 8/10. Patients suffered from left GON neuralgia in 13 cases, right GON neuralgia in 16 cases and bilateral GON neuralgia in 4 cases. The clinical success rate was 86 %. In case of clinical success, the mean pain relief duration following the procedure was 9.16 months. Simplified CT-guided infiltration appears to be effective in managing refractory ON. With this technique, infiltration of the GON appears to be faster, technically easier and, therefore, safer compared with other previously described techniques. • Occipital neuralgia is a very painful and debilitating condition • GON infiltrations have been successful in the treatment of occipital neuralgia • This simplified technique presents a high efficacy rate with long-lasting pain relief • This infiltration technique does not require contrast media injection for pre-planning • GON infiltration at the first bend appears easier and safer.

  2. Dynamics of flood water infiltration and ground water recharge in hyperarid desert.

    Science.gov (United States)

    Dahan, Ofer; Tatarsky, Boaz; Enzel, Yehouda; Kulls, Christoph; Seely, Mary; Benito, Gererdo

    2008-01-01

    A study on flood water infiltration and ground water recharge of a shallow alluvial aquifer was conducted in the hyperarid section of the Kuiseb River, Namibia. The study site was selected to represent a typical desert ephemeral river. An instrumental setup allowed, for the first time, continuous monitoring of infiltration during a flood event through the channel bed and the entire vadose zone. The monitoring system included flexible time domain reflectometry probes that were designed to measure the temporal variation in vadose zone water content and instruments to concurrently measure the levels of flood and ground water. A sequence of five individual floods was monitored during the rainy season in early summer 2006. These newly generated data served to elucidate the dynamics of flood water infiltration. Each flood initiated an infiltration event which was expressed in wetting of the vadose zone followed by a measurable rise in the water table. The data enabled a direct calculation of the infiltration fluxes by various independent methods. The floods varied in their stages, peaks, and initial water contents. However, all floods produced very similar flux rates, suggesting that the recharge rates are less affected by the flood stages but rather controlled by flow duration and available aquifer storage under it. Large floods flood the stream channel terraces and promote the larger transmission losses. These, however, make only a negligible contribution to the recharge of the ground water. It is the flood duration within the active streambed, which may increase with flood magnitude that is important to the recharge process.

  3. Eosinophilic infiltration in Korea: idiopathic?

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Jae Hoon; Lee, Kyung Soo [Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2006-03-15

    Eosinophilia is defined as the presence of more than 500 eosinophils/{mu}L in the peripheral blood, and may be accompanied by eosinophil infiltration in tissues. Focal eosinophilic infiltration in the lungs and liver is relatively common and is often associated with a parasitic infection, drug hypersensitivity, allergic diseases, collagen vascular diseased, and internal malignancies such as Hodgkin's disease, as well as cancer of the lung, stomach, pancreas or ovary. An eosinophilic abscess refers to a lesion of massive eosinophil infiltration and associated destroyed tissue, and an eosinophilic granuloma refers to a lesion consisting of central necrosis and mixed inflammatory cell infiltrates with numerous eosinophils, a number of neutrophils and lymphocytes, and a palisade of epithelioid histiocytes and/or giant cells.

  4. Eosinophilic infiltration in Korea: idiopathic?

    International Nuclear Information System (INIS)

    Lim, Jae Hoon; Lee, Kyung Soo

    2006-01-01

    Eosinophilia is defined as the presence of more than 500 eosinophils/μL in the peripheral blood, and may be accompanied by eosinophil infiltration in tissues. Focal eosinophilic infiltration in the lungs and liver is relatively common and is often associated with a parasitic infection, drug hypersensitivity, allergic diseases, collagen vascular diseased, and internal malignancies such as Hodgkin's disease, as well as cancer of the lung, stomach, pancreas or ovary. An eosinophilic abscess refers to a lesion of massive eosinophil infiltration and associated destroyed tissue, and an eosinophilic granuloma refers to a lesion consisting of central necrosis and mixed inflammatory cell infiltrates with numerous eosinophils, a number of neutrophils and lymphocytes, and a palisade of epithelioid histiocytes and/or giant cells

  5. An indoor air quality study of 40 East Tennessee homes

    International Nuclear Information System (INIS)

    Hawthorne, A.R.; Gammage, R.B.; Dudney, C.S.

    1986-01-01

    Over a 1-yr period, measurements of indoor air pollutants (COsub(x), NOsub(x), formaldehyde, volatile organics, particulate matter, and radon) were made in 40 homes in east Tennessee. The houses were of various ages with different types of insulation and heating. In 30% of the houses, the radon concentration exceeded 4 pCi/L. The mean radon level in houses built near ridgelines was 4.4 pCi/L, while houses located in the valleys had a mean level of 1.7 pCi/L. The factor having the most impact on infiltration was operation of the central duct fan of the heating, ventilation, and air conditioning system. For measurements made before December 1984, the mean rate of air exchange increased from 0.39 to 0.74 h -1 when the duct fan was operated. (author)

  6. Modeling runoff and microbial overland transport with KINEROS2/STWIR model: Accuracy and uncertainty as affected by source of infiltration parameters

    Science.gov (United States)

    Infiltration is important to modeling the overland transport of microorganisms in environmental waters. In watershed- and hillslope scale-models, infiltration is commonly described by simple equations relating infiltration rate to soil saturated conductivity and by empirical para...

  7. Measurement of HOx· production rate due to radon decay in air

    International Nuclear Information System (INIS)

    Ding, Huiling.

    1993-08-01

    Radon in indoor air may cause the exposure of the public to excessive radioactivity. Radiolysis of water vapor in indoor air due to radon decay could produce (·OH and HO 2 ·) that may convert atmospheric constituents to compounds of lower vapor pressure. These lower vapor pressure compounds might then nucleate to form new particles in the indoor atmosphere. Chemical amplification was used to determine HO x · production rate in indoor air caused by radon decay. Average HO x · production rate was found to be (4.31±0.07) x 10 5 HO x · per Rn decay per second (Bq) 3.4 to 55.0% at 22C. This work provided G (HO x ·) -value, 7.86±0.13 No./100 eV in air by directly measuring [HO x ·] formed from the radiolysis procedure. This G value implies that HO x · produced by radon decay in air might be formed by multiple processes and may be result of positive ion-molecule reactions, primary radiolysis, and radical reactions. There is no obvious relation between HO x · production rate and relative humidity. A laser-induced fluorescence (LIF) system has been used for ·OH production rate measurement; it consists of an excimer laser, a dye laser, a frequency doubler, a gaseous fluorescence chamber, and other optical and electronic parts. This system needs to be improved to eliminate the interferences of light scattering and artificial ·OH produced from the photolysis of O 3 /H 2 O

  8. Modeling snowmelt infiltration in seasonally frozen ground

    Science.gov (United States)

    Budhathoki, S.; Ireson, A. M.

    2017-12-01

    In cold regions, freezing and thawing of the soil govern soil hydraulic properties that shape the surface and subsurface hydrological processes. The partitioning of snowmelt into infiltration and runoff has also important implications for integrated water resource management and flood risk. However, there is an inadequate representation of the snowmelt infiltration into frozen soils in most land-surface and hydrological models, creating the need for improved models and methods. Here we apply, the Frozen Soil Infiltration Model, FroSIn, which is a novel algorithm for infiltration in frozen soils that can be implemented in physically based models of coupled flow and heat transport. In this study, we apply the model in a simple configuration to reproduce observations from field sites in the Canadian prairies, specifically St Denis and Brightwater Creek in Saskatchewan, Canada. We demonstrate the limitations of conventional approaches to simulate infiltration, which systematically over-predict runoff and under predict infiltration. The findings show that FroSIn enables models to predict more reasonable infiltration volumes in frozen soils, and also represent how infiltration-runoff partitioning is impacted by antecedent soil moisture.

  9. Application of the rainfall infiltration breakthrough (RIB) model for ...

    African Journals Online (AJOL)

    Application of the rainfall infiltration breakthrough (RIB) model for groundwater recharge estimation in west coastal South Africa. ... the data from Oudebosch with different rainfall and groundwater abstraction inputs are simulated to explore individual effects on water levels as well as recharge rate estimated on a daily basis.

  10. Water infiltration in soil at catchment scale: consequences for cold-climate regions

    OpenAIRE

    Stolte, J.; French, H.K.; Ritsema, C.J.

    2008-01-01

    Soil erosion is a global problem because of its environmental consequences, including sedimentation and pollution in many areas of the world. An estimated 400 million hectares of land have been abandoned due to soil erosion over the past 50 years. The main biophysical factor influencing the quantity of overland flow is the infiltration rate. Infiltration during a runoff-generating rainfall event is regulated by the hydraulic properties of the Critical Zone and the antecedent soil moisture con...

  11. Rate of water infiltration into soil on a selected location at Žabčice during the growing season 2008

    Directory of Open Access Journals (Sweden)

    M. Vičanová

    2010-01-01

    Full Text Available Purpose of currently running research, which is part of research program Biological and technological aspects of sustainability of controlled ecosystems and their adaptability to climate change at Faculty of Agronomy, is mapping of progress in water infiltration on selected areas at Žabčice locality and to specify possibilities of a water accumulation and retention influence in a landscape.During of the first year of measurement (2008, from April to November, has proceeded field measurement of soil infiltration ability at Žabčice locality. To get statistically conclusive results, measurement runs in three repetitions and data are subsequently averaged. Three sets of homocentric metal cylinders were used for the measurement. Measurement of infiltration has been preceded by an overflow. Empirical equations according to Kosťjak were used for evaluation of field measurement.At the same time there were ensured intact soil samples for laboratory determination of soil physical properties using Kopecky cylinders at depths of 10, 20 and 30 cm, and for the calculation of selected hydro-physical parameters of soil.­ reduced volume weight, actual monture, porosity, aeration and other.Graphical presentation presents process of speed infiltration and cumulative infiltration on selected area Niva IV. A. Non-homogeneity of measured values could be induced by several different factors.

  12. Clinical application of bupivacaine in non-catheter infiltration anesthesia during vitrectomy

    Directory of Open Access Journals (Sweden)

    Peng Zhang

    2017-12-01

    Full Text Available AIM: To evaluate the effect of bupivacaine in non-catheter infiltration anesthesia during vitretomy operation. METHODS: Fifty-eight patients(58 eyeswith vitreous retinal surgery were selected. Patients were randomly divided into observation group(28 eyesand control group(30 eyes. The observation group were received non-catheter infiltration anesthesia. The control group were received traditional Sub-Tenon's block(STB. Degree of pain, basic vital signs, the duration of anesthesia and analgesia grade were recorded and compared between two groups.RESULTS: No significant difference was found in the 11-point numeric rating scale(NRS-11 scoringof anesthesia process, sclera incision, intraocular operation and the end of operation between two groups(P>0.05. The difference were not significant in heart rate and blood pressure between two groups(P>0.05. There was statistically significant difference in the duration of anesthesia between two groups(PCONCLUSION: Both groups can provide the same anesthetic effect. Compared to STB, non-catheter infiltration anesthesia takes short time, and it is a safe and effective anesthesia methods. In addition, compare to the mixture of bupivacaine and lidocaine injection, bupivacaine injection can provide the same anesthetic effect.

  13. Infiltration characteristics of non-aqueous phase liquids in undisturbed loessal soil cores.

    Science.gov (United States)

    Wang, Yunqiang; Shao, Ming'an

    2009-01-01

    The widespread contamination of soils and aquifers by non-aqueous phase liquids (NAPL), such as crude oil, poses serious environmental and health hazards globally. Understanding the infiltration characteristics of NAPL in soil is crucial in mitigating or remediating soil contamination. The infiltration characteristics of crude and diesel oils into undisturbed loessal soil cores, collected in polymethyl methacrylate cylindrical columns, were investigated under a constant fluid head (3 cm) of either crude oil or diesel oil. The infiltration rate of both crude and diesel oils decreased exponentially as wetting depth increased with time. Soil core size and bulk density both had significant effects on NAPL infiltration through the undisturbed soil cores; a smaller core size or a greater bulk density could reduce oil penetration to depth. Compacting soil in areas susceptible to oil spills may be an effective stratage to reduce contamination. The infiltration of NAPL into soil cores was spatially anisotropic and heterogeneous, thus recording the data at four points on the soil core is a good stratage to improve the accuracy of experimental results. Our results revealed that crude and diesel oils, rather than their components, have a practical value for remediation of contaminated loessal soils.

  14. Passive Microwave Observation of Soil Water Infiltration

    Science.gov (United States)

    Jackson, Thomas J.; Schmugge, Thomas J.; Rawls, Walter J.; ONeill, Peggy E.; Parlange, Marc B.

    1997-01-01

    Infiltration is a time varying process of water entry into soil. Experiments were conducted here using truck based microwave radiometers to observe small plots during and following sprinkler irrigation. Experiments were conducted on a sandy loam soil in 1994 and a silt loam in 1995. Sandy loam soils typically have higher infiltration capabilities than clays. For the sandy loam the observed brightness temperature (TB) quickly reached a nominally constant value during irrigation. When the irrigation was stopped the TB began to increase as drainage took place. The irrigation rates in 1995 with the silt loam soil exceeded the saturated conductivity of the soil. During irrigation the TB values exhibited a pattern that suggests the occurrence of coherent reflection, a rarely observed phenomena under natural conditions. These results suggested the existence of a sharp dielectric boundary (wet over dry soil) that was increasing in depth with time.

  15. A study on groundwater infiltration in the Horonobe area, northern Hokkaido, Japan

    International Nuclear Information System (INIS)

    Yokota, Hideharu; Yamamoto, Yoichi; Maekawa, Keisuke; Hara, Minoru

    2011-01-01

    In the Horonobe area of northern Hokkaido, the Japan Atomic Energy Agency has been carrying out various hydrological observations to estimate the recharge rate. Subsurface earth temperature and soil moisture content have been observed at HGW-1 site (GL-0.7m to GL-2.3m, since 2005) and Hokushin Meteorological Station (GL-0.1m to GL-1.1m, since 2008). The results have revealed groundwater infiltration and recharge occurring throughout year, the shallow groundwater-infiltration velocity depending on the depth and the position of the Zero Flux Plane. For the estimation of boundary conditions in groundwater flow simulation, in this study, the shallow groundwater-flow system has been examined qualitatively on the basis of the variation of the subsurface earth temperature and the soil moisture content. In the future, it is necessary to quantitatively assess the shallow groundwater infiltration and recharge rate, the intermediate runoff, and the evapotranspiration based on the observed data of the weighing lysimeter, and the other measurement stations in the area. (author)

  16. Vegetation succession and soil infiltration characteristics under different aged refuse dumps at the Heidaigou opencast coal mine

    Directory of Open Access Journals (Sweden)

    Huang Lei

    2015-07-01

    Full Text Available Vegetation succession and soil infiltration characteristics under five different restoration models of refuse dumps including different-aged revegetated sites (1995, 1998, 2003 and 2005 in the northern, eastern and western open-pit coal mine dump and a reference site with native vegetation, which had never been damaged by coal mining activities on the Heidaigou Open Cut Coal Mine were studied. Changes in the plant species, soil properties and infiltration rates were evaluated at the different refuse dumps. The results indicated that the number of herbaceous species, plant cover, biomass, fine particles, and total N, P and SOM increased significantly with increasing site age. However, the number of shrub species decreased since revegetation, its cover increased from 17% to 41% initially and subsequently decreased to the present level of 4%. The natural vegetation community and the northern refuse dump had the highest cumulative infiltration rates of 3.96 and 2.89 cm s−1 in contrast to the eastern and western refuse dumps and the abandoned land, where the highest cumulative infiltration rates were 1.26, 1.04 and 0.88 cm s−1, respectively. A multiple linear regression analysis indicated that the infiltration rate was primarily determined by the silt percentage, SOM, plant coverage and the variation in soil bulk density. Our results provide new ideas regarding future soil erosion controls and sustainable development at open-pit coal mine refuse dumps.

  17. Effect of Air Injection on Nucleation Rates

    DEFF Research Database (Denmark)

    Capellades Mendez, Gerard; Kiil, Søren; Dam-Johansen, Kim

    2017-01-01

    From disruption of the supersaturated solution to improved mass transfer in the crystallizing suspension, the introduction of a moving gas phase in a crystallizer could lead to improved rates of nucleation and crystal growth. In this work, saturated air has been injected to batch crystallizers...... to study the effects on formation of the first crystal and subsequent turbidity buildup. To account for the typically large sample-to-sample variation, nucleation rates were evaluated for a large number of replicates using probability distributions of induction times. The slope and the intercept...... was reduced from 69 to 13 min, and the mean induction time decreased from 128 to 36 min. The effect on aqueous solutions of l-arginine was less apparent, with a detection delay reduction from 15 to 3 min, and no significant changes on the rate of primary nucleation. These results demonstrate the potential...

  18. Buccal Infiltration versus Inferior Alveolar Nerve Block in Mandibular ...

    African Journals Online (AJOL)

    2018-04-04

    Apr 4, 2018 ... Purpose: The purpose of this study is to compare the success rates of inferior alveolar nerve block (IANB) and buccal infiltration anesthesia of mandibular second premolar with irreversible pulpitis and to evaluate the level of patient discomfort with these methods. Matherials and Methods: Forty patients, who.

  19. Pollution from Urban Stormwater Infiltration

    DEFF Research Database (Denmark)

    Mikkelsen, Peter Steen; Weyer, G.; Berry, C.

    1994-01-01

    Stormwater infiltration in urban areas gives cause for concern with regard to the risk of soil and groundwater pollution. Compared with conventional storm drainage, infiltration introduces different and widely unknown conditions governing the impacts and the fate of the pollutants......, and it is therefore difficult to assess the overall environmental impact. This paper gives a state of the art assessment of the water quality aspects of stormwater infiltration and proposes ways of managing the inherent problems. The major stormwater pollution sources are highlighted and the different processes...

  20. Infiltrating/sealing proximal caries lesions

    DEFF Research Database (Denmark)

    Martignon, S; Ekstrand, K R; Gomez, J

    2012-01-01

    This randomized split-mouth controlled clinical trial aimed at assessing the therapeutic effects of infiltration vs. sealing for controlling caries progression on proximal surfaces. Out of 90 adult students/patients assessed at university clinics and agreeing to participate, 39, each with 3...... differences in lesion progression between infiltration and placebo (P = 0.0012) and between sealing and placebo (P = 0.0269). The study showed that infiltration and sealing are significantly better than placebo treatment for controlling caries progression on proximal lesions. No significant difference...

  1. Indoor air quality in a multifamily apartment building before and after energy renovation

    DEFF Research Database (Denmark)

    Bekö, Gabriel; Földváry, Veronika; Langer, Sarka

    2016-01-01

    Buildings are responsible for a substantial portion of global energy consumption. Most of the multifamily residential buildings in central Europe built in the 20th century do not satisfy the current requirements on energy efficiency. Nationwide remedial measures are taken to improve the energy ef...... exchange rates and acceptable and healthy IAQ. Without these considerations, energy reconstruction can adversely affect the quality of the indoor environment....... efficiency of these buildings and reduce their energy consumption. Since the impact of these measures on the indoor air quality is rarely considered, they often compromise indoor air quality due to decreased ventilation and infiltration rate. We compared the indoor air quality in a multifamily apartment...... building in Slovakia before and after energy renovation, during two subsequent winters. Measurements of temperature, relative humidity, concentrations of CO2, formaldehyde, NO2, and volatile organic compounds were performed during one week in January 2015 in 20 apartments in one multifamily building...

  2. Numerical analysis on infiltration-driven decarbonation during skarnification

    Science.gov (United States)

    Chu, X.; Lee, C. T.; Dasgupta, R.

    2017-12-01

    Interaction of arc magmas with carbonate sequences on active margins leads to contact metamorphism and metasomatism by infiltrating magmatic fluids. This skarnification process releases CO2 to the metasomatic fluids, which transport carbon to shallow reservoirs and can affect the long-term carbon budget in the exogenic system [1]. In this study, we apply a self-consistent 1D finite difference model to an impure marble consisting of quartz and calcite, in a similar scheme as ref [2]. The Darcian flow is modeled with a fixed boundary condition of water influx, taking into account the reaction kinetics [3,4] and pore space compaction. The modeling results show that the reaction front lags the fluid infiltration front and propagates at the rate scaling with: = k × [infiltrating fluid flux] / [reactant amount], where k is a function of the reaction kinetics and rock rheology. The reaction front does not advance until one reactant is exhausted; thus a protolith assemblage of 50:50 quartz:calcite has the slowest-moving reaction front. The steady-state carbon flux scales with the distance of reaction front to comply with mass conservation, and thus yields a linear relationship with the infiltrating flux and is largely independent of the protolith quartz:calcite ratio. Assuming that the rate of global magma emplacement on the continental arcs is 3 km3/yr [5], the arc magmas exsolve 5 vol.% water as they crystallize, and 40% of such magmas intrude carbonate sequences, the total steady-state carbon flux due to skarnification is 0.2 Tmol/yr. By contrast, Mount Etna alone emits carbon up to 0.2 Tmol/yr, most of which is the product of magma-carbonate interaction [6]. We note that the infiltration of pure water produces a wollastonite marble; natural metasomatic fluid is saturated with silica and other components, which leads to greater decarbonation and the formation of calc-silicate skarn. Wallrock assimilation also adds to the carbon flux from arcs, so the simplified

  3. Numerical modeling of cold room's hinged door opening and closing processes

    Science.gov (United States)

    Carneiro, R.; Gaspar, P. D.; Silva, P. D.; Domingues, L. C.

    2016-06-01

    The need of rationalize energy consumption in agrifood industry has fasten the development of methodologies to improve the thermal and energy performances of cold rooms. This paper presents a three-dimensional (3D) transient Computational Fluid Dynamics (CFD) modelling of a cold room to evaluate the air infiltration rate through hinged doors. A species transport model is used for modelling the tracer gas concentration decay technique. Numerical predictions indicate that air temperature difference between spaces affects the air infiltration. For this case study, the infiltration rate increases 0.016 m3 s-1 per K of air temperature difference. The knowledge about the evolution of air infiltration during door opening/closing times allows to draw some conclusions about its influence on the air conditions inside the cold room, as well as to suggest best practices and simple technical improvements that can minimize air infiltration, and consequently improve thermal performance and energy consumption rationalization.

  4. UNSAT-H infiltration model calibration at the Subsurface Disposal Area, Idaho National Engineering Laboratory

    International Nuclear Information System (INIS)

    Martian, P.

    1995-10-01

    Soil moisture monitoring data from the expanded neutron probe monitoring network located at the Subsurface Disposal Area (SDA) of the Idaho National Engineering Laboratory (INEL) were used to calibrate numerical infiltration models for 15 locations within and near the SDA. These calibrated models were then used to simulate infiltration into the SDA surficial sediments and underlying basalts for the entire operational period of the SDA (1952--1995). The purpose of performing the simulations was to obtain a time variant infiltration source term for future subsurface pathway modeling efforts as part of baseline risk assessment or performance assessments. The simulation results also provided estimates of the average recharge rate for the simulation period and insight into infiltration patterns at the SDA. These results suggest that the average aquifer recharge rate below the SDA may be at least 8 cm/yr and may be as high as 12 cm/yr. These values represent 38 and 57% of the average annual precipitation occurring at the INEL, respectively. The simulation results also indicate that the maximum evaporative depth may vary between 28 and 148 cm and is highly dependent on localized lithology within the SDA

  5. Combined geophysical methods for mapping infiltration pathways at the Aurora Water Aquifer recharge and recovery site

    Science.gov (United States)

    Jasper, Cameron A.

    Although aquifer recharge and recovery systems are a sustainable, decentralized, low cost, and low energy approach for the reclamation, treatment, and storage of post- treatment wastewater, they can suffer from poor infiltration rates and the development of a near-surface clogging layer within infiltration ponds. One such aquifer recharge and recovery system, the Aurora Water site in Colorado, U.S.A, functions at about 25% of its predicted capacity to recharge floodplain deposits by flooding infiltration ponds with post-treatment wastewater extracted from river bank aquifers along the South Platte River. The underwater self-potential method was developed to survey self-potential signals at the ground surface in a flooded infiltration pond for mapping infiltration pathways. A method for using heat as a groundwater tracer within the infiltration pond used an array of in situ high-resolution temperature sensing probes. Both relatively positive and negative underwater self-potential anomalies are consistent with observed recovery well pumping rates and specific discharge estimates from temperature data. Results from electrical resistivity tomography and electromagnetics surveys provide consistent electrical conductivity distributions associated with sediment textures. A lab method was developed for resistivity tests of near-surface sediment samples. Forward numerical modeling synthesizes the geophysical information to best match observed self- potential anomalies and provide permeability distributions, which is important for effective aquifer recharge and recovery system design, and optimization strategy development.

  6. Measurement of Air Flow Rate in a Naturally Ventilated Double Skin Facade

    DEFF Research Database (Denmark)

    Kalyanova, Olena; Jensen, Rasmus Lund; Heiselberg, Per

    2007-01-01

    Air flow rate in a naturally ventilated space is extremely difficult to measure due to the stochastic nature of wind, and as a consequence non-uniform and dynamic flow conditions. This paper describes three different methods to measure the air flow in a full-scale outdoor test facility...... with a naturally ventilated double skin façade. In the first method, the air flow in the cavity is estimated on the basis of six measured velocity profiles. The second method is represented by constant injection of tracer gas and in the third method a measured relation in the laboratory is used to estimate...... the flow rate on the basis of continues measurement of the pressure difference between the surface pressure at the opening and inside pressure of the double skin façade. Although all three measurement methods are difficult to use under such dynamic air flow conditions, two of them show reasonable agreement...

  7. Multi-rate path-following control for unmanned air vehicles

    NARCIS (Netherlands)

    Guerreiro Tome Antunes, D.J.; Silvestre, C.J.; Cunha, R.

    2008-01-01

    A methodology is provided to tackle the path-following integrated guidance and control problem for unmanned air vehicles with measured outputs available at different rates. The path-following problem is addressed by defining a suitable non-linear path dependent error space to express the vehicle’s

  8. Detailed evaluation of the natural circulation mass flow rate of water propelled by using an air injection

    International Nuclear Information System (INIS)

    Park, Rae-Joon; Ha, Kwang-Soon; Kim, Jae-Cheol; Hong, Seong-Wan; Kim, Sang-Baik

    2008-01-01

    One-dimensional (1D) air-water two-phase natural circulation flow in the thermohydraulic evaluation of reactor cooling mechanism by external self-induced flow - one-dimensional' (THERMES-1D) experiment has been verified and evaluated by using the RELAP5/MOD3 computer code. Experimental results on the 1D natural circulation mass flow rate of water propelled by using an air injection have been evaluated in detail. The RELAP5 results have shown that an increase in the air injection rate to 50% of the total heat flux leads to an increase in the water circulation mass flow rate. However, an increase in the air injection rate from 50 to 100% does not affect the water circulation mass flow rate, because of the inlet area condition. As the height increases in the air injection part, the void fraction increases. However, the void fraction in the upper part of the air injector maintains a constant value. An increase in the air injection mass flow rate leads to an increase in the local void fraction, but it has no influence on the local pressure. An increase in the coolant inlet area leads to an increase in the water circulation mass flow rate. However, the water outlet area does not have an influence on the water circulation mass flow rate. As the coolant outlet moves to a lower position, the water circulation mass flow rate decreases. (author)

  9. Air change rates of motor vehicles and in-vehicle pollutant concentrations from secondhand smoke.

    Science.gov (United States)

    Ott, Wayne; Klepeis, Neil; Switzer, Paul

    2008-05-01

    The air change rates of motor vehicles are relevant to the sheltering effect from air pollutants entering from outside a vehicle and also to the interior concentrations from any sources inside its passenger compartment. We made more than 100 air change rate measurements on four motor vehicles under moving and stationary conditions; we also measured the carbon monoxide (CO) and fine particle (PM(2.5)) decay rates from 14 cigarettes smoked inside the vehicle. With the vehicle stationary and the fan off, the ventilation rate in air changes per hour (ACH) was less than 1 h(-1) with the windows closed and increased to 6.5 h(-1) with one window fully opened. The vehicle speed, window position, ventilation system, and air conditioner setting was found to affect the ACH. For closed windows and passive ventilation (fan off and no recirculation), the ACH was linearly related to the vehicle speed over the range from 15 to 72 mph (25 to 116 km h(-1)). With a vehicle moving, windows closed, and the ventilation system off (or the air conditioner set to AC Max), the ACH was less than 6.6 h(-1) for speeds ranging from 20 to 72 mph (32 to 116 km h(-1)). Opening a single window by 3'' (7.6 cm) increased the ACH by 8-16 times. For the 14 cigarettes smoked in vehicles, the deposition rate k and the air change rate a were correlated, following the equation k=1.3a (R(2)=82%; n=14). With recirculation on (or AC Max) and closed windows, the interior PM(2.5) concentration exceeded 2000 microg m(-3) momentarily for all cigarettes tested, regardless of speed. The concentration time series measured inside the vehicle followed the mathematical solutions of the indoor mass balance model, and the 24-h average personal exposure to PM(2.5) could exceed 35 microg m(-3) for just two cigarettes smoked inside the vehicle.

  10. Expression of JMJD2A in infiltrating duct carcinoma was markedly higher than fibroadenoma, and associated with expression of ARHI, p53 and ER in infiltrating duct carcinoma.

    Science.gov (United States)

    Li, Bei-Xu; Li, Jia; Luo, Cheng-Liang; Zhang, Ming-Chang; Li, Hui; Li, Li-Liang; Xu, Hong-Fei; Shen, Yi-Wen; Xue, Ai-Min; Zhao, Zi-Qin

    2013-03-01

    Jumonji Domain Containing 2A (JMJD2A) may be a cancer-associated gene involved in human breast cancer. With a view to investigating expression of JMJD2A in human breast cancer and benign lesion tissues as well as relationship between JMJD2A and tumor related proteins, histological and immunohistochemical analysis, Western blot and quantitative real-time PCR in infiltrating duct carcinoma and fibroadenoma for JMJD2A and immunohistochemical analysis and quantitative real-time PCR in infiltrating duct carcinoma for tumor related proteins (ARHI, p53, ER, PR and CerbB-2) were performed. Histological examination validated the clinical diagnosis. The JMJD2A positive rate of infiltrating duct carcinoma was significantly higher than fibroadenoma by immunohistochemical analysis. The mean optical density of JMJD2A in infiltrating duct carcinoma was higher than fibroadenoma by western blot. JMJD2A mRNA level in infiltrating duct carcinoma was higher than fibroadenoma by quantitative real-time PCR. Spearman correlation analysis revealed that the expression of JMJD2A was associated with ARHI, p53 and ER from immunohistochemical results respectively. Pearson correlation analysis revealed that the expression of JMJD2A was associated with ARHI, p53 and ER from quantitative real-time PCR results respectively. Expression of JMJD2A in infiltrating duct carcinoma was higher, and associated with ARHI, p53 and ER. The results may take JMJD2A as a potential diagnostic and therapeutic target in human breast cancer.

  11. Application of subsurface wastewater infiltration system to on-site treatment of domestic sewage under high hydraulic loading rate

    Directory of Open Access Journals (Sweden)

    Ying-hua Li

    2015-01-01

    Full Text Available In order to enhance the hydraulic loading rate (HLR of a subsurface wastewater infiltration system (SWIS used in treating domestic sewage, the intermittent operation mode was employed in the SWIS. The results show that the intermittent operation mode contributes to the improvement of the HLR and the pollutant removal rate. When the wetting-drying ratio (RWD was 1.0, the pollutant removal rate increased by (13.6 ± 0.3% for NH3-N, (20.7 ± 1.1% for TN, (18.6 ± 0.4% for TP, (12.2 ± 0.5% for BOD, (10.1 ± 0.3% for COD, and (36.2 ± 1.2% for SS, compared with pollutant removal rates under the continuous operation mode. The pollutant removal rate declined with the increase of the HLR. The effluent quality met The Reuse of Urban Recycling Water – Water Quality Standard for Scenic Environment Use (GB/T 18921-2002 even when the HLR was as high as 10 cm/d. Hydraulic conductivity, oxidation reduction potential (ORP, the quantity of nitrifying bacteria, and the pollutant removal rate of NH3-N increased with the decrease of the RWD. For the pollutant removal rates of TP, BOD, and COD, there were no significant difference (p < 0.05 under different RWDs. The suggested RWD was 1.0. Relative contribution of the pretreatment and SWIS to the pollutant removal was examined, and more than 80% removal of NH3-N, TN, TP, COD, and BOD occurred in the SWIS.

  12. An Open Pit Nanofluidic Tool: Localized Chemistry Assisted by Mesoporous Thin Film Infiltration.

    Science.gov (United States)

    Mercuri, Magalí; Pierpauli, Karina A; Berli, Claudio L A; Bellino, Martín G

    2017-05-17

    Nanofluidics based on nanoscopic porous structures has emerged as the next evolutionary milestone in the construction of versatile nanodevices with unprecedented applications. However, the straightforward development of nanofluidically interconnected systems is crucial for the production of practical devices. Here, we demonstrate that spontaneous infiltration into supramolecularly templated mesoporous oxide films at the edge of a sessile drop in open air can be used to connect pairs of landmarks. The liquids from the drops can then join through the nanoporous network to guide a localized chemical reaction at the nanofluid-front interface. This method, here named "open-pit" nanofluidics, allows mixing reagents from nanofluidically connected droplet reservoirs that can be used as reactors to conduct reactions and precipitation processes. From the fundamental point of view, the work contributes to unveiling subtle phenomena during spontaneous infiltration of fluids in bodies with nanoscale dimensions such as the front broadening effect and the oscillatory behavior of the infiltration-evaporation front. The approach has distinctive advantages such as easy fabrication, low cost, and facility of scaling up for future development of ultrasensitive detection, controlled nanomaterial synthesis, and novel patterning methods.

  13. Adductor canal block with local infiltrative analgesia compared with local infiltrate analgesia for pain control after total knee arthroplasty

    OpenAIRE

    Xing, Qiujuan; Dai, Weiwei; Zhao, Dongfeng; Wu, Ji; Huang, Chunshui; Zhao, Yun

    2017-01-01

    Abstract Background: This meta-analysis aimed to evaluate the efficiency and safety of the combined adductor canal block with peri-articular infiltration versus periarticular infiltration alone for pain control after total knee arthroplasty (TKA). Methods: PubMed, Medline, Embase, Web of Science, and the Cochrane Library were searched to identify articles comparing the combined adductor canal block with peri-articular infiltration and periarticular infiltration alone for pain control after TK...

  14. Correlation between spiral CT features of pericolic infiltration and tumor angiogenesis in colorectal carcinoma

    International Nuclear Information System (INIS)

    Zhang Ruiping; Li Jianding

    2007-01-01

    Objective: To investigate the correlation of spiral CT (SCT) features with pathology, microvessel density (MVD), expression of vascular endothelial growth factor (VEGF), matrix metalloproteinase-2( MMP-2) in colorectal carcinoma. Methods: Forty patients with colorectal carcinoma confirmed by operation were examined by SCT. The resected tumor specimens were immunohistochemically stained for the expression of VEGF, MMP-2 and the calculation of MVD. Results: The accuracy of SCT in depicting the pericolic and wall infiltration was 92.5%. The metastasis rates of colorectal cancer with pericolic infiltration and wall infiltration were 75.0% and 33.3%, respectively, the differences were statistically significant between the two groups (P<0.05). The differences of CT enhancement value, MVD, expressions of VEGF and MMP-2 between the two groups were statistically significant (P<0.05). The enhancement degree of CT had a positive correlation with MVD (P<0.05). Conclusion: SCT is accurate for depicting pericolic and wall infiltration, pericolic infiltration in colorectal carcinoma indicates the tendency of metastasis. The enhancement degree of CT might be used to quantitatively evaluate the tumor angiogenesis, expressions of VEGF and MMP-2 and MVD are closely correlated with the infiltration of colorectal cancer. (authors)

  15. Wintertime Air-Sea Gas Transfer Rates and Air Injection Fluxes at Station Papa in the NE Pacific

    Science.gov (United States)

    McNeil, C.; Steiner, N.; Vagle, S.

    2008-12-01

    In recent studies of air-sea fluxes of N2 and O2 in hurricanes, McNeil and D'Asaro (2007) used a simplified model formulation of air-sea gas flux to estimate simultaneous values of gas transfer rate, KT, and air injection flux, VT. The model assumes air-sea gas fluxes at high to extreme wind speeds can be explained by a combination of two processes: 1) air injection, by complete dissolution of small bubbles drawn down into the ocean boundary layer by turbulent currents, and 2) near-surface equilibration processes, such as occurs within whitecaps. This analysis technique relies on air-sea gas flux estimates for two gases, N2 and O2, to solve for the two model parameters, KT and VT. We present preliminary results of similar analysis of time series data collected during winter storms at Station Papa in the NE Pacific during 2003/2004. The data show a clear increase in KT and VT with increasing NCEP derived wind speeds and acoustically measured bubble penetration depth.

  16. The influences of ambient particle composition and size on particle infiltration in Los Angeles, CA, residences.

    Science.gov (United States)

    Sarnat, Stefanie Ebelt; Coull, Brent A; Ruiz, Pablo A; Koutrakis, Petros; Suh, Helen H

    2006-02-01

    Particle infiltration is a key determinant of the indoor concentrations of ambient particles. Few studies have examined the influence of particle composition on infiltration, particularly in areas with high concentrations of volatile particles, such as ammonium nitrate (NH4NO3). A comprehensive indoor monitoring study was conducted in 17 Los Angeles-area homes. As part of this study, indoor/outdoor concentration ratios during overnight (nonindoor source) periods were used to estimate the fraction of ambient particles remaining airborne indoors, or the particle infiltration factor (FINF), for fine particles (PM2.5), its nonvolatile (i.e., black carbon [BC]) and volatile (i.e., nitrate [NO3-]) components, and particle sizes ranging between 0.02 and 10 microm. FINF was highest for BC (median = 0.84) and lowest for NO3- (median = 0.18). The low FINF for NO3- was likely because of volatilization of NO3- particles once indoors, in addition to depositional losses upon building entry. The FINF for PM2.5 (median = 0.48) fell between those for BC and NO3-, reflecting the contributions of both particle components to PM25. FINF varied with particle size, air-exchange rate, and outdoor NO3- concentrations. The FINF for particles between 0.7 and 2 microm in size was considerably lower during periods of high as compared with low outdoor NO3- concentrations, suggesting that outdoor NO3- particles were of this size. This study demonstrates that infiltration of PM2.5 varies by particle component and is lowest for volatile species, such as NH4NO3. Our results suggest that volatile particle components may influence the ability for outdoor PM concentrations to represent indoor and, thus, personal exposures to particles of ambient origin, because volatilization of these particles causes the composition of PM2.5 to differ indoors and outdoors. Consequently, particle composition likely influences observed epidemiologic relationships based on outdoor PM concentrations, especially in areas

  17. Research on the infiltration processes of lawn soils of the Babao River in the Qilian Mountain.

    Science.gov (United States)

    Li, GuangWen; Feng, Qi; Zhang, FuPing; Cheng, AiFang

    2014-01-01

    Using a Guelph Permeameter, the soil water infiltration processes were analyzed in the Babao River of the Qilian Mountain in China. The results showed that the average soil initial infiltration and the steady infiltration rates in the upstream reaches of the Babao River are 1.93 and 0.99 cm/min, whereas those of the middle area are 0.48 cm/min and 0.21 cm/min, respectively. The infiltration processes can be divided into three stages: the rapidly changing stage (0-10 min), the slowly changing stage (10-30 min) and the stabilization stage (after 30 min). We used field data collected from lawn soils and evaluated the performances of the infiltration models of Philip, Kostiakov and Horton with the sum of squared error, the root mean square error, the coefficient of determination, the mean error, the model efficiency and Willmott's index of agreement. The results indicated that the Kostiakov model was most suitable for studying the infiltration process in the alpine lawn soils.

  18. Evaluation of Surface Infiltration Testing Procedures in Permeable Pavement Systems

    Science.gov (United States)

    The ASTM method (ASTM C1701) for measuring infiltration rate of in-place pervious concrete provides limited guidance on how to select testing locations, so research is needed to evaluate how testing sites should be selected and how results should be interpreted to assess surface ...

  19. Linking chloride mass balance infiltration rates with chlorofluorocarbon and SF6 groundwater dating in semi-arid settings: potential and limitations.

    Science.gov (United States)

    Stadler, Susanne; Osenbruck, Karsten; Duijnisveld, Wilhelmus H M; Schwiede, Martin; Bottcher, Jurgen

    2010-09-01

    In the framework of the investigation of enrichment processes of nitrate in groundwater of the Kalahari of Botswana near Serowe, recharge processes were investigated. The thick unsaturated zone extending to up to 100 m of mostly unconsolidated sediments and very low recharge rates pose a serious challenge to study solute transport related to infiltration and recharge processes, as this extends past the conventional depths of soil scientific investigations and is difficult to describe using evidence from the groundwater due to the limitations imposed by available tracers. To determine the link between nitrate in the vadose zone and in the uppermost groundwater, sediment from the vadose zone was sampled up to a depth of 15-20 m (in one case also to 65 m) on several sites with natural vegetation in the research area. Among other parameters, sediment and water were analysed to determine chloride and nitrate concentration depth profiles. Using the chloride mass balance method, an estimation of groundwater infiltration rates produced values of 0.2-4 mm a(-1). The uncertainty of these values is, however, high. Because of the extreme thickness of the vadose zone, the travel time in the unsaturated zone might reach extreme values of up to 500 years and more. For investigations using groundwater, we applied the chlorofluorocarbons CFC-113, CFC-12, sulphur hexafluoride (SF(6)) and tritium to identify potential recharge, and found indications for some advective transport of the CFCs and SF(6), which we accounted for as constituting potential active localised recharge. In our contribution, we show the potential and limitations of the applied methods to determine groundwater recharge and coupled solute transport in semi-arid settings, and compare travel time ranges derived from soil science and groundwater investigations.

  20. Modified technology in new constructions, and cost effective remedial action in existing structures, to prevent infiltration of soil gas carrying radon

    International Nuclear Information System (INIS)

    Ericson, S.O.; Schmid, H.; Clavensjo, B.

    1984-01-01

    The general principles and mechanisms of how soil gas carrying radon infiltrates from the foundation bed and subsoil into buildings are discussed. The Swedish Building Research Council has funded experiments and evaluations of cost effective remedial actions. The work has concerned existing dwellings with high concentration of radon where this is a result of infiltrating soil gas and/or exhalation from building materials. A review is given of experience and results acquired up to the summer of 1983. 100 dwellings have been erected with consideration of possible infiltration of soil gas. Modification of design, added costs (investment and operation) and resulting concentration of radon in indoor air is discussed. In general minor modifications are sufficient. (author)

  1. Artificial Recharge – Measurement of Soil Infiltration in Rožnov Pod Radhoštěm

    Directory of Open Access Journals (Sweden)

    Chromíková Jitka

    2017-12-01

    Full Text Available The purpose of this study is to evaluate the potential for infiltration in a study area – Rožnov pod Radhoštěm, the Czech Republic. The results are important for the future design of an artificial recharge structure as a method to store water underground in times of water surplus. A total of six measurements of infiltration were made using a double ring infiltrometer on selected prospective sites for the future application of artificial recharge. The results of infiltration tests were analysed based on the Philip’s model. The steady soil infiltration rates ranged from 28 cm∙h−1 to 70.38 cm∙h−1and the cumulative soil infiltration ranged from 58 cm to 68 cm.

  2. Measurement of the Air Chance Rate and Ventilation Characteristics During Short Term Transient Phenomena

    DEFF Research Database (Denmark)

    Heiselberg, Per Kvols; Perino, M.

    2004-01-01

    Different measurement procedures are available for the experimental assessment of air change rates inside ventilated enclosures. These mainly consist of tracer gas techniques and can usually be applied to steady-state or moderately transient conditions and when a continous mixing of the indoor air...... ventilation. The results are critically compared with the air flow rates assessed through anemometric measurements. The measurement features, limitations, shortcomings and uncertainties are also discussed....... is assured throughout the test. However, due to the relatively slow response of the gas analysers, none of these procedures can usually be applied to fast transient phenomena that last 15 minutes or less. Moreover in many cases of natural ventilation strategies, the continuous mixing of the indoor air would...

  3. The performance and subjective responses of call-center operators with new and used supply air filters at two outdoor air supply rates

    DEFF Research Database (Denmark)

    Wargocki, Pawel; Wyon, David; Fanger, Povl Ole

    2004-01-01

    A 2X2 replicated field intervention experiment was conducted in a call-center providing a telephone directory service: outdoor air supply rate was adjusted to be 8% of the total airflow of 430 l/s (3.5/h)and the supply air filters were either new or had been in place for 6 months. One of these in......A 2X2 replicated field intervention experiment was conducted in a call-center providing a telephone directory service: outdoor air supply rate was adjusted to be 8% of the total airflow of 430 l/s (3.5/h)and the supply air filters were either new or had been in place for 6 months. One...

  4. Infiltration performance of engineered surfaces commonly used for distributed stormwater management.

    Science.gov (United States)

    Valinski, N A; Chandler, D G

    2015-09-01

    Engineered porous media are commonly used in low impact development (LID) structures to mitigate excess stormwater in urban environments. Differences in infiltrability of these LID systems arise from the wide variety of materials used to create porous surfaces and subsequent maintenance, debris loading, and physical damage. In this study, the infiltration capacity of six common materials was tested by multiple replicate experiments with automated mini-disk infiltrometers. The tested materials included porous asphalt, porous concrete, porous brick pavers, flexible porous pavement, engineered soils, and native soils. Porous asphalt, large porous brick pavers, and curb cutout rain gardens showed the greatest infiltration rates. Most engineered porous pavements and soils performed better than the native silt loam soils. Infiltration performance was found to be related more to site design and environmental factors than material choice. Sediment trap zones in both pavements and engineered soil rain gardens were found to be beneficial to the whole site performance. Winter chloride application had a large negative impact on poured in place concrete, making it a poor choice for heavily salted areas. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Liquid infiltration through the boiling-point isotherm in a desiccating fractured rock matrix

    International Nuclear Information System (INIS)

    Phillips, O.M.

    1994-01-01

    Over a long time interval, the integrity of the radioactive waste repository proposed at Yucca Mountain may be compromised by corrosion accelerated by intermittent wetting which could occur by episodic infiltration of meteoric water from above through the fracture network. A simple two-dimensional model is constructed for the infiltration of liquid water down a fracture in a permeable rock matrix, beyond the boiling-point isotherm. The water may derive from episodic infiltration or from the condensation of steam above a desiccating region. Boiling of the water in the fracture is maintained by heat transfer from a surrounding superheated matrix blocks. There are two intrinsic length scales in this situation, (1): l s = ρ l q o L/(k m β) which is such that the total heat flow over this lateral distance balances that needed for evaporation of the liquid water infiltration, and (2): The thermal diffusion distance l θ = (k m t) 1/2 which increases with time after the onset of infiltration. The primary results are: (a) for two-dimensional infiltration down an isolated fracture or fault, the depth of penetration below the (undisturbed) boiling point isotherm is given by 1/2 π 1/2 (l s l θ ) 1/2 , and so increases as t 1/4 . Immediately following the onset of infiltration, penetration is rapid, but quickly slows. This behavior continues until l θ (and D) become comparable with l s . (b) With continuing infiltration down an isolated fracture or cluster of fractures, when l θ >> l s the temperature distribution becomes steady and the penetration distance stabilizes at a value proportional to l s . (c) Effects such as three-dimensionality of the liquid flow paths and flow rates, matrix infiltration, etc., appear to reduce the penetration distance

  6. Infiltration characteristics of non-aqueous phase liquids in undisturbed loessal soil cores

    Institute of Scientific and Technical Information of China (English)

    WANG Yunqiang; SHAO Ming'an

    2009-01-01

    The widespread contamination of soils and aquifers by non-aqueous phase liquids (NAPL), such as crude oil, poses serious environmental and health hazards globally. Understanding the infiltration characteristics of NAPL in soil is crucial in mitigating or remediating soil contamination. The infiltration characteristics of crude and diesel oils into undisturbed loessal soil cores, collected in polymethyl methacrylate cylindrical columns, were investigated under a constant fluid head (3 cm) of either crude oil or diesel oil. The infiltration rate of both crude and diesel oils decreased exponentially as wetting depth increased with time. Soil core size and bulk density both had a significant effect on NAPL infiltration through the undisturbed soil cores; a smaller core size or a greater bulk density both reduced oil penetration to depth. Compacting soil in areas susceptible to oil spills may be an effective way to reduce contamination. The infiltration of NAPL into soil cores was spatially anisotropic and heterogeneous, thus recording the data at four points on the soil core is a good way to improve the accuracy of experimental results. Our results provided information about crude and diesel oils, rather than their components, and may have practical value for remediation of contaminated loessal soils.

  7. Stormwater infiltration and the 'urban karst' - A review

    Science.gov (United States)

    Bonneau, Jeremie; Fletcher, Tim D.; Costelloe, Justin F.; Burns, Matthew J.

    2017-09-01

    The covering of native soils with impervious surfaces (e.g. roofs, roads, and pavement) prevents infiltration of rainfall into the ground, resulting in increased surface runoff and decreased groundwater recharge. When this excess water is managed using stormwater drainage systems, flow and water quality regimes of urban streams are severely altered, leading to the degradation of their ecosystems. Urban streams restoration requires alternative approaches towards stormwater management, which aim to restore the flow regime towards pre-development conditions. The practice of stormwater infiltration-achieved using a range of stormwater source-control measures (SCMs)-is central to restoring baseflow. Despite this, little is known about what happens to the infiltrated water. Current knowledge about the impact of stormwater infiltration on flow regimes was reviewed. Infiltration systems were found to be efficient at attenuating high-flow hydrology (reducing peak magnitudes and frequencies) at a range of scales (parcel, streetscape, catchment). Several modelling studies predict a positive impact of stormwater infiltration on baseflow, and empirical evidence is emerging, but the fate of infiltrated stormwater remains unclear. It is not known how infiltrated water travels along the subsurface pathways that characterise the urban environment, in particular the 'urban karst', which results from networks of human-made subsurface pathways, e.g. stormwater and sanitary sewer pipes and associated high permeability trenches. Seepage of groundwater into and around such pipes is possible, meaning some infiltrated stormwater could travel along artificial pathways. The catchment-scale ability of infiltration systems to restore groundwater recharge and baseflow is thus ambiguous. Further understanding of the fate of infiltrated stormwater is required to ensure infiltration systems deliver optimal outcomes for waterway flow regimes.

  8. Role of slope on infiltration: A review

    Science.gov (United States)

    Morbidelli, Renato; Saltalippi, Carla; Flammini, Alessia; Govindaraju, Rao S.

    2018-02-01

    Partitioning of rainfall at the soil-atmosphere interface is important for both surface and subsurface hydrology, and influences many events of major hydrologic interest such as runoff generation, aquifer recharge, and transport of pollutants in surface waters as well as the vadose zone. This partitioning is achieved through the process of infiltration that has been widely investigated at the local scale, and more recently also at the field scale, by models that were designed for horizontal surfaces. However, infiltration, overland flows, and deep flows in most real situations are generated by rainfall over sloping surfaces that bring in additional effects. Therefore, existing models for local infiltration into homogeneous and layered soils and those as for field-scale infiltration, have to be adapted to account for the effects of surface slope. Various studies have investigated the role of surface slope on infiltration based on a theoretical formulations for the dynamics of infiltration, extensions of the Green-Ampt approach, and from laboratory and field experiments. However, conflicting results have been reported in the scientific literature on the role of surface slope on infiltration. We summarize the salient points from previous studies and provide plausible reasons for discrepancies in conclusions of previous authors, thus leading to a critical assessment of the current state of our understanding on this subject. We offer suggestions for future efforts to advance our knowledge of infiltration over sloping surfaces.

  9. ''In situ'' investigations of the radioactive fissionable element infiltration and retention in different soils

    International Nuclear Information System (INIS)

    Oncescu, M.; Danis, A.; Sahagia, M.; Negrescu, C.; Bobe, M.; Balanescu, P.; Burcescu, M.; Tautu, N.

    1980-01-01

    ''In situ'' investigations of the natural and forced infiltration and retention of the fissionable elements from a liquid residue in several natural compacted soils and compacted clays are presented. The velocities and flow rates for different stages of the residue infiltration are determined. The retention of the fissionable elements by variation of the fissionable element concentration with the distance from the place of the residue depot is investigated. (author)

  10. Infiltration on mountain slopes: a comparison of three environments.

    Science.gov (United States)

    Carol P. Harden*; P. Delmas Scruggs

    2003-01-01

    Water is well established as a major driver of the geomorphic change that eventually reduces mountains to lower relief landscapes. Nonetheless, within the altitudinal limits of continuous vegetation in humid climates, water is also an essential factor in slope stability. In this paper, we present results from field experiments to determine infiltration rates at...

  11. Urban Stormwater Infiltration Perspectives

    DEFF Research Database (Denmark)

    Geldof, Govert; Jacobsen, Per; Fujita, Shoichi

    1994-01-01

    In urban areas there are many problems with water management: combined sewer overflows, peak flows, man-induced droughts, consolidation of the soil, damage from frost penetration, etc. It is preferable to look at all these problems in relation to each other, according the concept of integrated...... water management. This paper focuses on the possibilities for urban stormwater infiltration. The results of three studies are presented. The first study concerns the flooding of the Shirako River in Tokyo. It is shown that with the help of stormwater infiltration the floods can be reduced remarkably....... The second study concerns combined sewer overflows and the discharge from treatment plants for catchments in Denmark and the Netherlands. When looking at the total yearly discharge from the combined sewer and the treatment plant, it is shown that infiltration is more effective than detention. The third study...

  12. SU-D-209-01: Can Fluoroscopic Air-Kerma Rates Be Reliably Measured with Solid-State Meters?

    International Nuclear Information System (INIS)

    Feng, C; Thai, L; Wagner, L; Ozus, B

    2016-01-01

    Purpose: Ionization chambers remain the standard for calibration of air-kerma rate measuring devices. Despite their strong energy-dependent response, solid state radiation detectors are increasingly used, primarily due to their efficiency in making standardized measurements. To test the reliability of these devices in measuring air-kerma rates, we compared ion chambers measurements with solid-state measurements for various mobile fluoroscopes operated at different beam qualities and air-kerma rates. Methods: Six mobile fluoroscopes (GE OEC models 9800 and 9900) were used to generate test beams. Using various field sizes and dose rate controls, copper attenuators and a lead attenuator were placed at the image receptor in varying combinations to generate a range of air-kerma rates. Air-kerma rates at 30 centimeters from the image receptors were measured using two 6-cm"3 ion chambers with electrometers (Radcal, models 1015 and 9015) and two with solid state detectors (Unfors Xi and Raysafe X2). No error messages occurred during measurements. However, about two months later, one solid-state device stopped working and was replaced by the manufacturer. Two out of six mobile fluoroscopic units were retested with the replacement unit. Results: Generally, solid state and ionization chambers agreed favorably well, with two exceptions. Before replacement of the detector, the Xi meter when set in the “RF High” mode deviated from ion chamber readings by factors of 2 and 10 with no message indicating error in measurement. When set in the “RF Low” mode, readings were within −4% to +3%. The replacement Xi detector displayed messages alerting the user when settings were not compatible with air-kerma rates. Conclusion: Air-kerma rates can be measured favorably well using solid-state devices, but users must be aware of the possibility that readings can be grossly in error with no discernible indication for the deviation.

  13. SU-D-209-01: Can Fluoroscopic Air-Kerma Rates Be Reliably Measured with Solid-State Meters?

    Energy Technology Data Exchange (ETDEWEB)

    Feng, C; Thai, L; Wagner, L [The University of Texas Health Science Center at Houston, Houston, TX (United States); Ozus, B [CHI St Luke’s Health, Baylor St Luke’s Medical Center, Houston, TX (United States)

    2016-06-15

    Purpose: Ionization chambers remain the standard for calibration of air-kerma rate measuring devices. Despite their strong energy-dependent response, solid state radiation detectors are increasingly used, primarily due to their efficiency in making standardized measurements. To test the reliability of these devices in measuring air-kerma rates, we compared ion chambers measurements with solid-state measurements for various mobile fluoroscopes operated at different beam qualities and air-kerma rates. Methods: Six mobile fluoroscopes (GE OEC models 9800 and 9900) were used to generate test beams. Using various field sizes and dose rate controls, copper attenuators and a lead attenuator were placed at the image receptor in varying combinations to generate a range of air-kerma rates. Air-kerma rates at 30 centimeters from the image receptors were measured using two 6-cm{sup 3} ion chambers with electrometers (Radcal, models 1015 and 9015) and two with solid state detectors (Unfors Xi and Raysafe X2). No error messages occurred during measurements. However, about two months later, one solid-state device stopped working and was replaced by the manufacturer. Two out of six mobile fluoroscopic units were retested with the replacement unit. Results: Generally, solid state and ionization chambers agreed favorably well, with two exceptions. Before replacement of the detector, the Xi meter when set in the “RF High” mode deviated from ion chamber readings by factors of 2 and 10 with no message indicating error in measurement. When set in the “RF Low” mode, readings were within −4% to +3%. The replacement Xi detector displayed messages alerting the user when settings were not compatible with air-kerma rates. Conclusion: Air-kerma rates can be measured favorably well using solid-state devices, but users must be aware of the possibility that readings can be grossly in error with no discernible indication for the deviation.

  14. Maintenance measures for preservation and recovery of permeable pavement surface infiltration rate--The effects of street sweeping, vacuum cleaning, high pressure washing, and milling.

    Science.gov (United States)

    Winston, Ryan J; Al-Rubaei, Ahmed M; Blecken, Godecke T; Viklander, Maria; Hunt, William F

    2016-03-15

    The surface infiltration rates (SIR) of permeable pavements decline with time as sediment and debris clog pore spaces. Effective maintenance techniques are needed to ensure the hydraulic functionality and water quality benefits of this stormwater control. Eight different small-scale and full-scale maintenance techniques aimed at recovering pavement permeability were evaluated at ten different permeable pavement sites in the USA and Sweden. Maintenance techniques included manual removal of the upper 2 cm of fill material, mechanical street sweeping, regenerative-air street sweeping, vacuum street sweeping, hand-held vacuuming, high pressure washing, and milling of porous asphalt. The removal of the upper 2 cm of clogging material did not significantly improve the SIR of concrete grid paves (CGP) and permeable interlocking concrete pavers (PICP) due to the inclusion of fines in the joint and bedding stone during construction, suggesting routine maintenance cannot overcome improper construction. For porous asphalt maintenance, industrial hand-held vacuum cleaning, pressure washing, and milling were increasingly successful at recovering the SIR. Milling to a depth of 2.5 cm nearly restored the SIR for a 21-year old porous asphalt pavement to like-new conditions. For PICP, street sweepers employing suction were shown to be preferable to mechanical sweepers; additionally, maintenance efforts may become more intensive over time to maintain a threshold SIR, as maintenance was not 100% effective at removing clogging material. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Evaluation of Soil Media for Stormwater Infiltration Best Management Practices (BMPs)

    Science.gov (United States)

    This project will improve the performance of structural management practices, and provide guidance that will allow designers to balance infiltration rates with sorption capacity. This project will also perform a standard column test procedure for evaluating candidate soil media.

  16. A simplified model for estimating population-scale energy impacts of building envelope air-tightening and mechanical ventilation retrofits

    Energy Technology Data Exchange (ETDEWEB)

    Logue, Jennifer M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Turner, William J. N. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Trinity College Dublin, Dublin (Ireland); Walker, Iain S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Singer, Brett C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-01-19

    Changing the air exchange rate of a home (the sum of the infiltration and mechanical ventilation airflow rates) affects the annual thermal conditioning energy. Large-scale changes to air exchange rates of the housing stock can significantly alter the residential sector's energy consumption. However, the complexity of existing residential energy models is a barrier to the accurate quantification of the impact of policy changes on a state or national level. The Incremental Ventilation Energy (IVE) model developed in this study combines the output of simple air exchange models with a limited set of housing characteristics to estimate the associated change in energy demand of homes. The IVE model was designed specifically to enable modellers to use existing databases of housing characteristics to determine the impact of ventilation policy change on a population scale. The IVE model estimates of energy change when applied to US homes with limited parameterisation are shown to be comparable to the estimates of a well-validated, complex residential energy model.

  17. ‘Sticky business’: The influence of streambed periphyton on particle deposition and infiltration

    Science.gov (United States)

    Salant, Nira L.

    2011-03-01

    Strong feedbacks exist between physical and ecological components of aquatic systems. Aquatic plants can alter flow and sedimentation patterns, in turn influencing habitat condition and organism responses. In this study, I investigate the interactions between streambed periphyton, particle deposition and infiltration, and flow hydraulics to determine the influence of these organisms on the local environment. In a series of flume experiments, I measured the effects of two contrasting forms of periphyton at several densities and growth stages on near-bed hydraulics, particle loss from the water column, surface deposition, and subsurface infiltration. Data show that periphyton assemblages altered the rate and quantity of particle deposition via several mechanisms, including shear stress modification, surface adhesion, and bed clogging. Although trends varied for different size classes within a suspension of fine sediment, diatoms and algae had distinctly different effects on hydraulics, deposition, and infiltration. In general, diatoms increased the rate of decline in suspended particle concentrations relative to non-periphyton surfaces by reducing shear stresses and enhancing surface deposition via adhesion. Increases in diatom biomass, however, reduced the quantity and depth of particle infiltration, presumably by clogging interstitial pore spaces, in turn lowering rates of concentration decline. In contrast, all algal growth stages had slower or similar rates of concentration decline compared to non-periphyton conditions, due to partial clogging by high biomass and a lack of adhesion at the bed surface. Clogging effects were counteracted at later growth stages, however, as late-stage algal structures increased shear stresses and downward advection, in turn increasing amounts of infiltration. Compiled data from several field studies and experiments demonstrate a positive relation between periphyton biomass and inorganic mass, but also show a wide range in the

  18. Soil Infiltration Characteristics in Agroforestry Systems and Their Relationships with the Temporal Distribution of Rainfall on the Loess Plateau in China.

    Science.gov (United States)

    Wang, Lai; Zhong, Chonggao; Gao, Pengxiang; Xi, Weimin; Zhang, Shuoxin

    2015-01-01

    Many previous studies have shown that land use patterns are the main factors influencing soil infiltration. Thus, increasing soil infiltration and reducing runoff are crucial for soil and water conservation, especially in semi-arid environments. To explore the effects of agroforestry systems on soil infiltration and associated properties in a semi-arid area of the Loess Plateau in China, we compared three plant systems: a walnut (Juglans regia) monoculture system (JRMS), a wheat (Triticum aestivum) monoculture system (TAMS), and a walnut-wheat alley cropping system (JTACS) over a period of 11 years. Our results showed that the JTACS facilitated infiltration, and its infiltration rate temporal distribution showed a stronger relationship coupled with the rainfall temporal distribution compared with the two monoculture systems during the growing season. However, the effect of JTACS on the infiltration capacity was only significant in shallow soil layer, i.e., the 0-40 cm soil depth. Within JTACS, the speed of the wetting front's downward movement was significantly faster than that in the two monoculture systems when the amount of rainfall and its intensity were higher. The soil infiltration rate was improved, and the two peaks of soil infiltration rate temporal distribution and the rainfall temporal distribution coupled in rainy season in the alley cropping system, which has an important significance in soil and water conservation. The results of this empirical study provide new insights into the sustainability of agroforestry, which may help farmers select rational planting patterns in this region, as well as other regions with similar climatic and environmental characteristics throughout the world.

  19. Soil Infiltration Characteristics in Agroforestry Systems and Their Relationships with the Temporal Distribution of Rainfall on the Loess Plateau in China.

    Directory of Open Access Journals (Sweden)

    Lai Wang

    Full Text Available Many previous studies have shown that land use patterns are the main factors influencing soil infiltration. Thus, increasing soil infiltration and reducing runoff are crucial for soil and water conservation, especially in semi-arid environments. To explore the effects of agroforestry systems on soil infiltration and associated properties in a semi-arid area of the Loess Plateau in China, we compared three plant systems: a walnut (Juglans regia monoculture system (JRMS, a wheat (Triticum aestivum monoculture system (TAMS, and a walnut-wheat alley cropping system (JTACS over a period of 11 years. Our results showed that the JTACS facilitated infiltration, and its infiltration rate temporal distribution showed a stronger relationship coupled with the rainfall temporal distribution compared with the two monoculture systems during the growing season. However, the effect of JTACS on the infiltration capacity was only significant in shallow soil layer, i.e., the 0-40 cm soil depth. Within JTACS, the speed of the wetting front's downward movement was significantly faster than that in the two monoculture systems when the amount of rainfall and its intensity were higher. The soil infiltration rate was improved, and the two peaks of soil infiltration rate temporal distribution and the rainfall temporal distribution coupled in rainy season in the alley cropping system, which has an important significance in soil and water conservation. The results of this empirical study provide new insights into the sustainability of agroforestry, which may help farmers select rational planting patterns in this region, as well as other regions with similar climatic and environmental characteristics throughout the world.

  20. Predicted infiltration for sodic/saline soils from reclaimed coastal areas: sensitivity to model parameters.

    Science.gov (United States)

    Liu, Dongdong; She, Dongli; Yu, Shuang'en; Shao, Guangcheng; Chen, Dan

    2014-01-01

    This study was conducted to assess the influences of soil surface conditions and initial soil water content on water movement in unsaturated sodic soils of reclaimed coastal areas. Data was collected from column experiments in which two soils from a Chinese coastal area reclaimed in 2007 (Soil A, saline) and 1960 (Soil B, nonsaline) were used, with bulk densities of 1.4 or 1.5 g/cm(3). A 1D-infiltration model was created using a finite difference method and its sensitivity to hydraulic related parameters was tested. The model well simulated the measured data. The results revealed that soil compaction notably affected the water retention of both soils. Model simulations showed that increasing the ponded water depth had little effect on the infiltration process, since the increases in cumulative infiltration and wetting front advancement rate were small. However, the wetting front advancement rate increased and the cumulative infiltration decreased to a greater extent when θ₀ was increased. Soil physical quality was described better by the S parameter than by the saturated hydraulic conductivity since the latter was also affected by the physical chemical effects on clay swelling occurring in the presence of different levels of electrolytes in the soil solutions of the two soils.

  1. Predicted Infiltration for Sodic/Saline Soils from Reclaimed Coastal Areas: Sensitivity to Model Parameters

    Directory of Open Access Journals (Sweden)

    Dongdong Liu

    2014-01-01

    Full Text Available This study was conducted to assess the influences of soil surface conditions and initial soil water content on water movement in unsaturated sodic soils of reclaimed coastal areas. Data was collected from column experiments in which two soils from a Chinese coastal area reclaimed in 2007 (Soil A, saline and 1960 (Soil B, nonsaline were used, with bulk densities of 1.4 or 1.5 g/cm3. A 1D-infiltration model was created using a finite difference method and its sensitivity to hydraulic related parameters was tested. The model well simulated the measured data. The results revealed that soil compaction notably affected the water retention of both soils. Model simulations showed that increasing the ponded water depth had little effect on the infiltration process, since the increases in cumulative infiltration and wetting front advancement rate were small. However, the wetting front advancement rate increased and the cumulative infiltration decreased to a greater extent when θ0 was increased. Soil physical quality was described better by the S parameter than by the saturated hydraulic conductivity since the latter was also affected by the physical chemical effects on clay swelling occurring in the presence of different levels of electrolytes in the soil solutions of the two soils.

  2. Modelling of the chemical state in groundwater infiltration systems

    International Nuclear Information System (INIS)

    Zysset, A.

    1993-01-01

    Groundwater is replenished by water stemming either from precipitations, lakes or rivers. The area where such an infiltration occurs is characterized by a change in the environmental conditions, such as a decrease of the flow velocity and an increase in the solid surface marking the boundary of the flow field. With these changes new chemical processes may become relevant to the transport behavior of contaminants. Since the rates of chemical processes usually are a function of the concentrations of several species, an understanding of infiltration sites may require a multicomponent approach. The present study aims at formulating a mathematical model together with its numerical solution for groundwater infiltration sites. Such a model should improve the understanding of groundwater quality changes related to infiltrating contaminants. The groundwater quality is of vital interest to men because at many places most of the drinking water originates from groundwater. In the first part of the present study two partial models are formulated: one accounting for the transport in a one-dimensional, homogeneous and saturated porous medium, the other accounting for chemical reactions. This second model is initially stated for general kinetic systems. Then, it is specified for two systems, namely for a system governed only by reactions which are fast compared to the transport processes and for a system with biologically mediated redox reactions of dissolved substrates. In the second part of the study a numerical solution to the model is developed. For this purpose, the two partial models are coupled. The coupling is either iterative as in the case of a system with fast reactions or sequential as in all other cases. The numerical solutions of simple test cases are compared to analytical solutions. In the third part the model is evaluated using observations of infiltration sites reported in the literature. (author) figs., tabs., 155 refs

  3. [Effects of rainfall intensity on rainfall infiltration and redistribution in soil on Loess slope land].

    Science.gov (United States)

    Li, Yi; Shao, Ming'an

    2006-12-01

    With simulation test, this paper studied the patterns of rainfall infiltration and redistribution in soil on typical Loess slope land, and analyzed the quantitative relations between the infiltration and redistribution and the movement of soil water and mass, with rainfall intensity as the main affecting factor. The results showed that rainfall intensity had significant effects on the rainfall infiltration and water redistribution in soil, and the microcosmic movement of soil water. The larger the rainfall intensity, the deeper the wetting front of rainfall infiltration and redistribution was, and the wetting front of soil water redistribution had a slower increase velocity than that of rainfall infiltration. The power function of the wetting front with time, and also with rainfall intensity, was fitted well. There was also a quantitative relation between the wetting front of rainfall redistribution and the duration of rainfall. The larger the rainfall intensity, the higher the initial and steady infiltration rates were, and the cumulative infiltration increased faster with time. Moreover, the larger the rainfall intensity, the smaller the wetting front difference was at the top and the end of the slope. With the larger rainfall intensity, both the difference of soil water content and its descending trend between soil layers became more obvious during the redistribution process on slope land.

  4. Simulation evaluation of NIST air-kerma rate calibration standard for electronic brachytherapy.

    Science.gov (United States)

    Hiatt, Jessica R; Rivard, Mark J; Hughes, H Grady

    2016-03-01

    Dosimetry for the model S700 50 kV electronic brachytherapy (eBT) source (Xoft, Inc., a subsidiary of iCAD, San Jose, CA) was simulated using Monte Carlo (MC) methods by Rivard et al. ["Calculated and measured brachytherapy dosimetry parameters in water for the Xoft Axxent x-ray source: An electronic brachytherapy source," Med. Phys. 33, 4020-4032 (2006)] and recently by Hiatt et al. ["A revised dosimetric characterization of the model S700 electronic brachytherapy source containing an anode-centering plastic insert and other components not included in the 2006 model," Med. Phys. 42, 2764-2776 (2015)] with improved geometric characterization. While these studies examined the dose distribution in water, there have not previously been reports of the eBT source calibration methods beyond that recently reported by Seltzer et al. ["New national air-kerma standard for low-energy electronic brachytherapy sources," J. Res. Natl. Inst. Stand. Technol. 119, 554-574 (2014)]. Therefore, the motivation for the current study was to provide an independent determination of air-kerma rate at 50 cm in airair(d=50 cm) using MC methods for the model S700 eBT source. Using CAD information provided by the vendor and disassembled sources, an MC model was created for the S700 eBT source. Simulations were run using the mcnp6 radiation transport code for the NIST Lamperti air ionization chamber according to specifications by Boutillon et al. ["Comparison of exposure standards in the 10-50 kV x-ray region," Metrologia 5, 1-11 (1969)], in air without the Lamperti chamber, and in vacuum without the Lamperti chamber. K̇air(d=50 cm) was determined using the *F4 tally with NIST values for the mass energy-absorption coefficients for air. Photon spectra were evaluated over 2 π azimuthal sampling for polar angles of 0° ≤ θ ≤ 180° every 1°. Volume averaging was averted through tight radial binning. Photon energy spectra were determined over all polar angles in both air and vacuum using

  5. Chromatographic determination of the rate and extent of absorption of air pollutants by sea water

    International Nuclear Information System (INIS)

    Nikolakaki, S.; Vassilakos, C.; Katsanos, N.A.

    1994-01-01

    A simple chromatographic method is developed to determine the rate constant for expulsion of an air pollutant from water or its diffusion parameter in the liquid, the rate constant for chemical reaction of the pollutant with water, its mass transfer coefficient in the liquid, and the partition coefficient between liquid water and air. From these physicochemical parameters, the absorption rate by sea water and, therefore, the depletion rate of a polluting substance from the air can be calculated, together with the equilibrium state of this absorption. The method has been applied to nitrogen dioxide being absorbed by triple-distilled water and by sea water, at various temperatures. From the temperature variation of the reaction rate constant and of the partition coefficient, the activation energy for the reaction and the differential heat of solution were determined. (orig.)

  6. Meningeal infiltration in recurrent nasopharyngeal carcinoma

    International Nuclear Information System (INIS)

    Chong, V.F.H.; Fan, Y.-F.

    2000-01-01

    Permeative infiltration of the meninges appears to be a distinct form of recurrent nasopharyngeal carcinoma (NPC). The present report of eight patients with recurrent NPC illustrates meningeal infiltration following basal foramina extension. Seven of the eight patients (88%) showed jugular foramen involvement. Three patients had concomitant infiltration of the foramen magnum. There was one patient showing spread through the foramen lacerum. Only four (50%) of these patients had clinically detectable tumour in the nasopharynx, while the other half showed deep submucosal recurrence with endoscopically unremarkable findings. Permeative meningeal infiltration appears to be a distinct form of NPC recurrence. It is important to recognize this phenomenon so as to optimize the treatment options. The imaging studies were reviewed and the following features were recorded: local nasopharyngeal recurrence, the manner of intracranial spread and site of meningeal infiltration. Four patients had only MRI, two had only CT and two patients had both CT and MRI. The presence or absence of intracranial tumour before treatment was also recorded. Two observers reviewed the images and results were arrived at by consensus. Copyright (1999) Blackwell Science Pty Ltd

  7. Measurement and Modelling of Air Flow Rate in a Naturally Ventilated Double Skin Facade

    DEFF Research Database (Denmark)

    Heiselberg, Per; Kalyanova, Olena; Jensen, Rasmus Lund

    2008-01-01

    Air flow rate in a naturally ventilated double skin façade (DSF) is extremely difficult to measure due to the stochastic nature of wind, and as a consequence non-uniform and dynamic flow conditions. This paper describes the results of two different methods to measure the air flow in a full...... by the thermal simulation program, BSim, based on measured weather boundary conditions are compared to the measured air temperature, temperature gradient and mass flow rate in the DSF cavity. The results show that it is possible to predict the temperature distribution and airflow in the DSF although some......-scale outdoor test facility with a naturally ventilated double skin façade. Although both methods are difficult to use under such dynamic air flow conditions, they show reasonable agreement and can be used for experimental validation of numerical models of natural ventilation air flow in DSF. Simulations...

  8. A review of reaction rates in high temperature air

    Science.gov (United States)

    Park, Chul

    1989-01-01

    The existing experimental data on the rate coefficients for the chemical reactions in nonequilibrium high temperature air are reviewed and collated, and a selected set of such values is recommended for use in hypersonic flow calculations. For the reactions of neutral species, the recommended values are chosen from the experimental data that existed mostly prior to 1970, and are slightly different from those used previously. For the reactions involving ions, the recommended rate coefficients are newly chosen from the experimental data obtained more recently. The reacting environment is assumed to lack thermal equilibrium, and the rate coefficients are expressed as a function of the controlling temperature, incorporating the recent multitemperature reaction concept.

  9. Ultrasound-Guided Intermediate Site Greater Occipital Nerve Infiltration: A Technical Feasibility Study.

    Science.gov (United States)

    Zipfel, Jonathan; Kastler, Adrian; Tatu, Laurent; Behr, Julien; Kechidi, Rachid; Kastler, Bruno

    2016-01-01

    Two studies recently reported that computed tomography (CT) guided infiltration of the greater occipital nerve at its intermediate site allows a high efficacy rate with long-lasting pain relief following procedure in occipital neuralgia and in various craniofacial pain syndromes. The purpose of our study was to evaluate the technical feasibility and safety of ultrasound-guided intermediate site greater occipital nerve infiltration. Retrospective study. This study was conducted at the imaging department of a 1,409 bed university hospital. Local institutional review board approval was obtained and written consent was waived. In this retrospective study, 12 patients suffering from refractory occipital neuralgia or craniofacial pain syndromes were included between April and October 2014. They underwent a total of 21 ultrasound-guided infiltrations. Infiltration of the greater occipital nerve was performed at the intermediate site of the greater occipital nerve, at its first bend between obliqus capitis inferior and semispinalis capitis muscles with local anestetics and cortivazol. Technical success was defined as satisfactory diffusion of added iodinated contrast media in the fatty space between these muscles depicted on control CT scan. We also reported first data of immediate block test efficacy and initial clinical efficacy at 7 days, one month, and 3 months, defined by a decrease of at least 50% of visual analog scale (VAS) scores. Technical success rate was 95.24%. Patients suffered from right unilateral occipital neuralgia in 3 cases, left unilateral occipital neuralgia in 2 cases, bilateral occipital neuralgia in 2 cases, migraine in one case, cervicogenic headache in one case, tension-type headache in 2 cases, and cluster headache in one case. Block test efficacy was found in 93.3% (14/15) cases. Clinical efficacy was found in 80% of cases at 7 days, in 66.7% of cases at one month and in 60% of cases at 3 months. No major complications were noted. Some of the

  10. Runoff and soil loss from bench terraces. 1. An event-based model of rainfall infiltration and surface runoff.

    NARCIS (Netherlands)

    van Dijk, A.I.J.M.; Bruijnzeel, L.A.

    2004-01-01

    Overland flow resulting from an excess of rain over infiltration is an essential component of many models of runoff and erosion from fields or catchments. The spatially variable infiltration (SVI) model and a set of associated equations relating depth of runoff and maximum rate of 'effective' runoff

  11. Anesthetic Efficacy of 4 % Articaine During Extraction of the Mandibular Posterior Teeth by Using Inferior Alveolar Nerve Block and Buccal Infiltration Techniques.

    Science.gov (United States)

    El-Kholey, Khalid E

    2017-03-01

    The study was designed to evaluate the anesthetic efficacy of 4 % articaine with 1:100,000 epinephrine (A100) in infiltration and inferior alveolar nerve block (IANB) anesthetic techniques for the pain control during extraction of the mandibular posterior teeth. This prospective randomized single-blind clinical trial included 100 patients needing extraction of at least two mandibular molars. Patients received either infiltration in the buccal vestibule opposite to the first molar supplemented with lingual infiltration or standard IANB with A100. For assessment of depth of anesthesia obtained by the two anaethetic techniques, presence or absence of pain during the extraction were rated using the visual analog scale. Fifty patients received infiltration anesthesia and fifty patients were anesthetized by IANB. The success rate of pain-free extraction after buccal infiltration was 94 %, whereas by using IANB with the same anesthetic it was 92 %. No statistical differences were detected in the success rates between the two anesthetic techniques ( P  = 0.15). Buccal Infiltration can be considered a good option during extraction of the mandibular molar and premolar teeth of course, with supplemental lingual anesthesia.

  12. Symmetrical parahiliar infiltrated, cough and dyspnoea

    International Nuclear Information System (INIS)

    Giraldo Estrada, Horacio; Escalante, Hector

    2004-01-01

    It is the case a patient to who is diagnosed symmetrical parahiliar infiltrated; initially she is diagnosed lymphoma Hodgkin, treaty with radiotherapy and chemotherapy, but the X rays of the thorax demonstrated parahiliars and paramediastinals infiltrated

  13. Measurement of air kerma rate for Cs-137 using different ionization chambers

    International Nuclear Information System (INIS)

    Mohammed, K. T. A.

    2013-07-01

    Due to the importance of radiation doses in medical field quality assurance should be established in order to maintain a reasonable balance between the purpose of application and exposure. This study had been carried out to achieve quality control for protection based on air kerma rate. Measurements were performed by using Cs-137 for the comparison of two working ionization chambers in secondary standard dosimetry laboratory of Sudan. Spherical ionization chamber L S-01 1000 cc S/N 912 and Farmer ionization chamber 2675 A 600 cc S/N 0511, respectively. The results obtained from this study have been represented as mean and their standard deviations shown in most cases remains at 5% uncertainly. Comparison between kinetic energy released per unit mass in air rate (air kerma rate) were obtained by using spherical ionization chamber L S-01 1000 cc S/N 912 and results have been determined using inverse square law. The differences have been represented as means and standard deviations with significant P-value less than 0.05. Spherical ionization chamber gives accurate, reproducible results with acceptable uncertainty which is more suitable for calibration of radiation detectors.(Author)

  14. Model and calculations for net infiltration

    International Nuclear Information System (INIS)

    Childs, S.W.; Long, A.

    1992-01-01

    In this paper a conceptual model for calculating net infiltration is developed and implemented. It incorporates the following important factors: viability of climate for the next 10,000 years, areal viability of net infiltration, and important soil/plant factors that affect the soil water budget of desert soils. Model results are expressed in terms of occurrence probabilities for time periods. In addition the variability of net infiltration is demonstrated both for change with time and differences among three soil/hydrologic units present at the site modeled

  15. Infiltration of water in disturbed soil columns as affected by clay dispersion and aggregate slaking

    OpenAIRE

    Amezketa, E.; Aragües, R.; Gazol, R.

    2004-01-01

    Soil crusting negatively affects the productivity and sustainability of irrigated agriculture, reducing water infiltration and plant emergence, and enhancing surface runoff and erosion. Clay dispersion and slaking of the aggregates at the soil surface are the main processes responsible for crusting. The infiltration rates (IR) of ten arid-zone soils in disturbed soil columns were measured and their relative susceptibilities to dispersion and slaking were determined. It was also examined wheth...

  16. Estimating biozone hydraulic conductivity in wastewater soil-infiltration systems using inverse numerical modeling.

    Science.gov (United States)

    Bumgarner, Johnathan R; McCray, John E

    2007-06-01

    During operation of an onsite wastewater treatment system, a low-permeability biozone develops at the infiltrative surface (IS) during application of wastewater to soil. Inverse numerical-model simulations were used to estimate the biozone saturated hydraulic conductivity (K(biozone)) under variably saturated conditions for 29 wastewater infiltration test cells installed in a sandy loam field soil. Test cells employed two loading rates (4 and 8cm/day) and 3 IS designs: open chamber, gravel, and synthetic bundles. The ratio of K(biozone) to the saturated hydraulic conductivity of the natural soil (K(s)) was used to quantify the reductions in the IS hydraulic conductivity. A smaller value of K(biozone)/K(s,) reflects a greater reduction in hydraulic conductivity. The IS hydraulic conductivity was reduced by 1-3 orders of magnitude. The reduction in IS hydraulic conductivity was primarily influenced by wastewater loading rate and IS type and not by the K(s) of the native soil. The higher loading rate yielded greater reductions in IS hydraulic conductivity than the lower loading rate for bundle and gravel cells, but the difference was not statistically significant for chamber cells. Bundle and gravel cells exhibited a greater reduction in IS hydraulic conductivity than chamber cells at the higher loading rates, while the difference between gravel and bundle systems was not statistically significant. At the lower rate, bundle cells exhibited generally lower K(biozone)/K(s) values, but not at a statistically significant level, while gravel and chamber cells were statistically similar. Gravel cells exhibited the greatest variability in measured values, which may complicate design efforts based on K(biozone) evaluations for these systems. These results suggest that chamber systems may provide for a more robust design, particularly for high or variable wastewater infiltration rates.

  17. Effect of Post-Infiltration Soil Aeration at Different Growth Stages on Growth and Fruit Quality of Drip-Irrigated Potted Tomato Plants (Solanum lycopersicum).

    Science.gov (United States)

    Li, Yuan; Jia, Zongxia; Niu, Wenquan; Wang, Jingwei; Zhang, Mingzhi

    2015-01-01

    Soil hydraulic principles suggest that post-infiltration hypoxic conditions would be induced in the plant root-zone for drip-irrigated tomato production in small pots filled with natural soil. No previous study specifically examined the response of tomato plants (Solanum lycopersicum) at different growth stages to low soil aeration under these conditions. A 2 × 6 factorial experiment was conducted to quantify effects of no post-infiltration soil aeration versus aeration during 5 different periods (namely 27-33, 34-57, 58-85, 86-99, and 27-99 days after sowing), on growth and fruit quality of potted single tomato plants that were sub-surface trickle-irrigated every 2 days at 2 levels. Soil was aerated by injecting 2.5 liters of air into each pot through the drip tubing immediately after irrigation. Results showed that post-infiltration aeration, especially during the fruit setting (34-57 DAS) and enlargement (58-85 DAS) growth stages, can positively influence the yield, root dry weight and activity, and the nutritional (soluble solids and vitamin C content), taste (titratable acidity), and market quality (shape and firmness) of the tomato fruits. Interactions between irrigation level and post-infiltration aeration on some of these fruit quality parameters indicated a need for further study on the dynamic interplay of air and water in the root zone of the plants under the conditions of this experiment.

  18. Effect of Post-Infiltration Soil Aeration at Different Growth Stages on Growth and Fruit Quality of Drip-Irrigated Potted Tomato Plants (Solanum lycopersicum.

    Directory of Open Access Journals (Sweden)

    Yuan Li

    Full Text Available Soil hydraulic principles suggest that post-infiltration hypoxic conditions would be induced in the plant root-zone for drip-irrigated tomato production in small pots filled with natural soil. No previous study specifically examined the response of tomato plants (Solanum lycopersicum at different growth stages to low soil aeration under these conditions. A 2 × 6 factorial experiment was conducted to quantify effects of no post-infiltration soil aeration versus aeration during 5 different periods (namely 27-33, 34-57, 58-85, 86-99, and 27-99 days after sowing, on growth and fruit quality of potted single tomato plants that were sub-surface trickle-irrigated every 2 days at 2 levels. Soil was aerated by injecting 2.5 liters of air into each pot through the drip tubing immediately after irrigation. Results showed that post-infiltration aeration, especially during the fruit setting (34-57 DAS and enlargement (58-85 DAS growth stages, can positively influence the yield, root dry weight and activity, and the nutritional (soluble solids and vitamin C content, taste (titratable acidity, and market quality (shape and firmness of the tomato fruits. Interactions between irrigation level and post-infiltration aeration on some of these fruit quality parameters indicated a need for further study on the dynamic interplay of air and water in the root zone of the plants under the conditions of this experiment.

  19. E-Area LLWF Vadose Zone Model: Probabilistic Model for Estimating Subsided-Area Infiltration Rates

    Energy Technology Data Exchange (ETDEWEB)

    Dyer, J. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Flach, G. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2017-12-12

    A probabilistic model employing a Monte Carlo sampling technique was developed in Python to generate statistical distributions of the upslope-intact-area to subsided-area ratio (AreaUAi/AreaSAi) for closure cap subsidence scenarios that differ in assumed percent subsidence and the total number of intact plus subsided compartments. The plan is to use this model as a component in the probabilistic system model for the E-Area Performance Assessment (PA), contributing uncertainty in infiltration estimates.

  20. Indoor air quality environmental information handbook: Building system characteristics

    International Nuclear Information System (INIS)

    1987-01-01

    This manual, the third in a series, focuses on residential building system characteristics and their effects on indoor air quality. The manual addresses: residential indoor air pollutants by source, indoor concentrations, health effects, source control and mitigation techniques, standards and guidelines; building system characteristics of air exchange, pollutant source strength, residence volume, site characteristics, structural design, construction, and operation, infiltration and ventilation system, building occupancy; and monitoring methods

  1. Analysis of Infiltration-Suction Response in Unsaturated Residual Soil Slope in Gelugor, Penang

    Science.gov (United States)

    Ashraf Mohamad Ismail, Mohd; Hasliza Hamzah, Nur; Min, Ng Soon; Hazreek Zainal Abidin, Mohd; Tajudin, Saiful Azhar Ahmad; Madun, Aziman

    2018-04-01

    Rainfall infiltration on residual soil slope may impair slope stability by altering the pore-water pressure in the soil. A study has been carried out on unsaturated residual soil slope in Gelugor, Penang to determine the changes in matric suction of residual soils at different depth due to rainwater infiltration. The sequence of this study includes the site investigation, field instrumentation, laboratory experiment and numerical modeling. Void ratio and porosity of soil were found to be decreasing with depth while the bulk density and dry density of soil increased due to lower porosity of soil at greater depth. Soil infiltration rate and matric suction of all depths decrease with the increase of volumetric water content as well as the degree of saturation. Numerical modeling was used to verify and predict the relationship between infiltration-suction response and degree of saturation. Numerical models can be used to integrate the rainfall scenarios into quantitative landslide hazard assessments. Thus, development plans and mitigation measures can be designed for estimated impacts from hazard assessments based on collected data.

  2. DEEP INFILTRATING ENDOMETRIOSIS

    Directory of Open Access Journals (Sweden)

    Martina Ribič-Pucelj

    2018-02-01

    Full Text Available Background: Endometriosis is not considered a unified disease, but a disease encompassing three differ- ent forms differentiated by aetiology and pathogenesis: peritoneal endometriosis, ovarian endometriosis and deep infiltrating endometriosis (DIE. The disease is classified as DIE when the lesions penetrate 5 mm or more into the retroperitoneal space. The estimated incidence of endometriosis in women of reproductive age ranges from 10–15 % and that of DIE from 3–10 %, the highest being in infertile women and in those with chronic pelvic pain. The leading symptoms of DIE are chronic pelvic pain which increases with age and correlates with the depth of infiltration and infertility. The most important diagnostic procedures are patient’s history and proper gynecological examination. The diagnosis is confirmed with laparoscopy. DIE can affect, beside reproductive organs, also bowel, bladder and ureters, therefore adi- tional diagnostic procedures must be performed preopertively to confirm or to exclude the involvement of the mentioned organs. Endometriosis is hormon dependent disease, there- fore several hormonal treatment regims are used to supress estrogen production but the symptoms recurr soon after caesation of the treatment. At the moment, surgical treatment with excision of all lesions, including those of bowel, bladder and ureters, is the method of choice but requires frequently interdisciplinary approach. Surgical treatment significantly reduces pain and improves fertility in inferile patients. Conclusions: DIE is not a rare form of endometriosis characterized by chronic pelvic pain and infertility. Medical treatment is not efficient. The method of choice is surgical treatment with excision of all lesions. It significantly reduces pelvic pain and enables high spontaneus and IVF preg- nacy rates.Therefore such patients should be treated at centres with experience in treatment of DIE and with possibility of interdisciplinary approach.

  3. Infiltration into cropped soils: effect of rain and sodium adsorption ratio-impacted irrigation water.

    Science.gov (United States)

    Suarez, Donald L; Wood, James D; Lesch, Scott M

    2008-01-01

    The sodium adsorption ratio (SAR) and salinity criteria for water suitability for irrigation have been developed for conditions where irrigation water is the only water source. It is not clear that these criteria are applicable to environments where there is a combination of rain and irrigation during the growing season. The interaction of rainfall with irrigation water is expected to result in increased sodicity hazard because of the low electrical conductivity of rain. In this study we examined the effects of irrigation waters of SAR 2, 4, 6, 8, and 10 mmol(1/2) L(-1/2) and electrical conductivities of 1 and 2 dS m(-1) on the infiltration rate of two soils with alternating cycles of rain (simulated with a rainfall sprinkler) and irrigation water, separated by drying cycles. The infiltration rate of surface samples from two soils, Kobase silty clay (fine, smectitic, frigid, Torrertic Haplustept) and Glendive very fine sandy loam (coarse-loamy, mixed superactive, calcareous, frigid Aridic Ustifluvent) were evaluated under alfalfa (Medicago sativa) cropped conditions for over 140 d and under full canopy cover. Reductions in infiltration were observed for both soils for SAR above 2, and the reductions became more severe with increasing SAR. Saturated hydraulic conductivity measurements taken from undisturbed cores at the end of the experiment were highly variable, suggesting that in situ infiltration measurements may be preferred when evaluating SAR effects.

  4. Analysis of Rainfall Infiltration Law in Unsaturated Soil Slope

    OpenAIRE

    Zhang, Gui-rong; Qian, Ya-jun; Wang, Zhang-chun; Zhao, Bo

    2014-01-01

    In the study of unsaturated soil slope stability under rainfall infiltration, it is worth continuing to explore how much rainfall infiltrates into the slope in a rain process, and the amount of rainfall infiltrating into slope is the important factor influencing the stability. Therefore, rainfall infiltration capacity is an important issue of unsaturated seepage analysis for slope. On the basis of previous studies, rainfall infiltration law of unsaturated soil slope is analyzed. Considering t...

  5. Evaluation of air flow rates through spargers for optimization of KNGR IRWST and SDVS design

    International Nuclear Information System (INIS)

    Jung, J. S.; Rha, I. S.; Jang, Y. S.; Koh, H. J.; Park, J. N.; Lee, S. W.

    1999-01-01

    In KNGR in the event of POSRVs actuation water, air and steam discharged from the RCS impose the dynamic loads on IRWST walls and submerged structures. The largest load is air clearing load. The main factors having an effect on the air clearing load are steam mass flux, the pressure and air volume in the POSRV discharge line. It is practically difficult to make the amount of air mass and its flow rates discharged through each sparger evenly distributed because several spargers are branched from one horizontal header. For an optimization of KNGR IRWST and SDVS design to minimize the T/H loads, the pressure in the discharge pipe and the air mass flow rates through spargers are evaluated using RELAP5/MOD3 code with changing the POSRV opening time and line and sparger arrangement. It is shown that as the opening time is the longer, the pressure in the discharge line is decreased and difference of the amount of air mass between spargers is reduced. And sparger headers with three spargers show better performance rather than those with six ones

  6. New options for the cold storage air curtain in the food sector; Koelruimte-luchtgordijn biedt nieuwe mogelijkheden

    Energy Technology Data Exchange (ETDEWEB)

    Bruins, K. [Biddle, Kootstertille (Netherlands)

    1997-10-01

    Based on a newly developed so-called multi air jet technology air curtains in front of cold spaces prevent warm air from infiltrating the cold space. The principles and performance of the cold space air curtain are briefly outlined. 2 figs.

  7. Removal of nitrogen by a layered soil infiltration system during intermittent storm events.

    Science.gov (United States)

    Cho, Kang Woo; Song, Kyung Guen; Cho, Jin Woo; Kim, Tae Gyun; Ahn, Kyu Hong

    2009-07-01

    The fates of various nitrogen species were investigated in a layered biological infiltration system under an intermittently wetting regime. The layered system consisted of a mulch layer, coarse soil layer (CSL), and fine soil layer (FSL). The effects of soil texture were assessed focusing on the infiltration rate and the removal of inorganic nitrogen species. The infiltration rate drastically decreased when the uniformity coefficient was larger than four. The ammonium in the synthetic runoff was shown to be removed via adsorption during the stormwater dosing and nitrification during subsequent dry days. Stable ammonium adsorption was observed when the silt and clay content of CSL was greater than 3%. This study revealed that the nitrate leaching was caused by nitrification during dry days. Various patterns of nitrate flushing were observed depending on the soil configuration. The washout of nitrate was more severe as the silt/clay content of the CSL was greater. However, proper layering of soil proved to enhance the nitrate removal. Consequently, a strictly sandy CSL over FSL with a silt and clay content of 10% was the best configuration for the removal of ammonium and nitrate.

  8. Evaluation of two stormwater infiltration trenches in central Copenhagen after 15 years of operation

    DEFF Research Database (Denmark)

    Bergman, Maria Kerstin; Hedegaard, Mathilde Jørgensen; Petersen, Mette Fjendbo

    2011-01-01

    to see whether the reduction in performance has continued and to determine how the system performs today. Water levels in the trenches were monitored for almost 4 months, and from this period seven events were selected to analyse the infiltration rate. A comparison with similar analyses on storm......Two stormwater infiltration trenches were installed in 1993 in an area in central Copenhagen. The system was monitored continuously for almost three years after establishment, and a small reduction in performance over that time, possibly due to clogging, was noted. A new study was conducted in 2009...... sequences from the first 3 years of operation shows that the infiltration has decreased since the establishment of the system 15 years ago. The decrease is statistically significant (p

  9. A comparison of measured and calculated values of air kerma rates from 137Cs in soil

    Directory of Open Access Journals (Sweden)

    V. P. Ramzaev

    2015-01-01

    Full Text Available In 2010, a study was conducted to determine the air gamma dose rate from 137Cs deposited in soil. The gamma dose rate measurements and soil sampling were performed at 30 reference plots from the south-west districts of the Bryansk region (Russia that had been heavily contaminated as a result of the Chernobyl accident. The 137Cs inventory in the top 20 cm of soil ranged from 260 kBq m–2 to 2800 kBq m–2. Vertical distributions of 137Cs in soil cores (6 samples per a plot were determined after their sectioning into ten horizontal layers of 2 cm thickness. The vertical distributions of 137Cs in soil were employed to calculate air kerma rates, K, using two independent methods proposed by Saito and Jacob [Radiat. Prot. Dosimetry, 1995, Vol. 58, P. 29–45] and Golikov et al. [Contaminated Forests– Recent Developments in Risk Identification and Future Perspective. Kluwer Academic Publishers, 1999. – P. 333–341]. A very good coincidence between the methods was observed (Spearman’s rank coefficient of correlation = 0.952; P<0.01; on average, a difference between the kerma rates calculated with two methods did not exceed 3%. The calculated air kerma rates agreed with the measured dose rates in air very well (Spearman’s coefficient of correlation = 0.952; P<0.01. For large grassland plots (n=19, the measured dose rates were on average 6% less than the calculated kerma rates. The tested methods for calculating the air dose rate from 137Cs in soil can be recommended for practical studies in radiology and radioecology. 

  10. Prospective validation of immunological infiltrate for prediction of response to neoadjuvant chemotherapy in HER2-negative breast cancer--a substudy of the neoadjuvant GeparQuinto trial.

    Science.gov (United States)

    Issa-Nummer, Yasmin; Darb-Esfahani, Silvia; Loibl, Sibylle; Kunz, Georg; Nekljudova, Valentina; Schrader, Iris; Sinn, Bruno Valentin; Ulmer, Hans-Ullrich; Kronenwett, Ralf; Just, Marianne; Kühn, Thorsten; Diebold, Kurt; Untch, Michael; Holms, Frank; Blohmer, Jens-Uwe; Habeck, Jörg-Olaf; Dietel, Manfred; Overkamp, Friedrich; Krabisch, Petra; von Minckwitz, Gunter; Denkert, Carsten

    2013-01-01

    We have recently described an increased lymphocytic infiltration rate in breast carcinoma tissue is a significant response predictor for anthracycline/taxane-based neoadjuvant chemotherapy (NACT). The aim of this study was to prospectively validate the tumor-associated lymphocyte infiltrate as predictive marker for response to anthracycline/taxane-based NACT. The immunological infiltrate was prospectively evaluated in a total of 313 core biopsies from HER2 negative patients of the multicenter PREDICT study, a substudy of the neoadjuvant GeparQuinto study. Intratumoral lymphocytes (iTuLy), stromal lymphocytes (strLy) as well as lymphocyte-predominant breast cancer (LPBC) were evaluated by histopathological assessment. Pathological complete response (pCR) rates were analyzed and compared between the defined subgroups using the exact test of Fisher. Patients with lymphocyte-predominant breast cancer (LPBC) had a significantly increased pCR rate of 36.6%, compared to non-LPBC patients (14.3%, pimmunological infiltrate in breast tumor tissue is predictive for response to anthracycline/taxane-based NACT. Patients with LPBC and increased stromal lymphocyte infiltration have significantly increased pCR rates. The lymphocytic infiltrate is a promising additional parameter for histopathological evaluation of breast cancer core biopsies.

  11. Radon and aldehyde concentrations in the indoor environment. Final report

    International Nuclear Information System (INIS)

    Moschandreas, D.J.; Rector, H.E.

    1981-04-01

    Findings regarding indoor air contaminants in the energy-efficient residence (EER) in Mt. Airy, Maryland are reported. The objectives of the study were to collect and analyze relevant air quality samples (specifically radon and aldehydes), characterize the indoor air quality with respect to radon and aldehydes, and develop relationships between air infiltration rates and contaminant levels. One-fifth of the measured formaldehyde concentrations were in the range that may cause health concerns. Although indoor temperature and relative humidity affect indoor HCHO concentration, the elevated formaldehyde concentrations were measured under very low air infiltration rates. The data show that ventilation of the indoor air space is somewhat effective in reducing high HCHO concentrations. The operation of the heat exchanger led to an increase of the air infiltration rate which in turn resulted in substantial reduction of formaldehyde concentrations. A considerable number of the collected samples of indoor air displayed radon concentrations at levels higher than 1.0 to 4.0 nCim -3 (assuming an equilibrium factor of 0.5, these radon levels would correspond to working levels above the health guidelines suggested by the US EPA for homes in Florida built on land reclaimed from phosphate mining). As in the case of indoor formaldehyde concentrations, elevated indoor concentrations are substantially reduced when the infiltration rate is increased. The data base shows that the use of the air to air heat exchanger leads to reduction of indoor radon concentration by increasing the residential ventilation rate

  12. General hydroisotopic study of direct infiltration and evaporation process through the unsaturated zone in Damascus oasis, Syrian Arab Republic

    International Nuclear Information System (INIS)

    Abou Zakhem, B.; Hafez, R.

    2001-01-01

    Damascus oasis plays an important economical and environmental role in the city life because it presents the surrounding green places and the groundwater is the main sources for irrigation. In this study we will focus on the unsaturated zone in Damascus oasis. Environmental isotopes as 18 O, 2 H and 3 H are considered one of the most important techniques that are used in unsaturated zone study in order to study the water movement mechanism, estimate the effective velocity, the rate and spatial variations of the direct infiltration through this zone.The Deuterium profile allow to estimate the direct evaporation rate, and it is observed that the evaporation in the eastern part of the studied area is 5-6.5 mm/y. The Tritium peak of profile that is belonging to the atmospheric nuclear tests at the beginning of the sixties indicates the effective infiltration velocity of 27.8 mm/y. The effective porosity was estimated about 6.5% and the permeability parameter is 0.6*10 -10 m/s. The direct infiltration rate was estimated by the chemical Chloride balance in the studied profiles in addition to their spatial distribution where it was distinguished between the eastern area where the direct infiltration is less than 2 mm/y characterized by very fine clay soils and western area where the direct infiltration rate is more than 2 mm/y with sandy soils. It is thought that the lower part of the unsaturated zone indicated the direct infiltration rate about 3.5 mm/y, under more wet climatic conditions where the rainfall was about 423 mm/y, this wet period was extended from about 432 y to more than 760y ago.The Nitrate concentration variation with depth indicated that unsaturated zone play important role as purification zone, and the groundwater which has more than 5 m depth is prevented from pollution, whereas the groundwater that has less than 5 m depth is more prone to pollution by high concentration of Nitrates. (author)

  13. [Effects of biochar addition into soils in semiarid land on water infiltration under the condition of the same bulk density].

    Science.gov (United States)

    Qi, Rui-Peng; Zhang, Lei; Yan, Yong-Hao; Wen, Man; Zheng, Ji-Yong

    2014-08-01

    Making clear the effects of biochar addition on soil water infiltration process can provide the scientific basis for the evaluation of the influence of biochar application on soil hydrology in semi-arid region. In this paper, through the soil column simulation method in laboratory, the effects of biochar of three sizes (1-2 mm, 0.25-1 mm and ≤ 0.25 mm) at 4 doses (10, 50, 100 and 150 g x kg(-1)) on the cumulative infiltration, the permeability and the stable infiltration rate of two different soils (anthrosol and aeolian sandy soil) were studied. The results showed that the infiltration capacity of the anthrosol was obviously increased compared to the control, however, the one in the aeolian sandy soil was decreased due to the biochar addition. At 100 minutes after infiltration starting, the averaged cumulative infiltration was increased by 25.1% in the anthrosol with comparison to the control. Contrarily, the averaged cumulative infiltration was decreased by 11.1% in the aeolian sandy soil at 15 minutes after infiltration starting. When the dose was the same, biochar with different particle sizes improved the infiltration for the anthrosol, but for the different dose treatments, the particle size of biochar which showed the greatest improvement was different. As for the aeolian sandy soil, the infiltration increased at the dose of 10 g x kg(-1) after the addition of biochar with different particle sizes, while decreased at the higher dose of 50, 100 and 150 g x kg(-1). The cumulative infiltration of the aeolian sandy soil was decreased with the increase in addition amount of biochar with the same particle size, while it was not so for the anthrosol. The determination coefficient fitted by the Philip infiltration model ranged from 0.965 to 0.999, suggesting this model was suitable for the simulation of soil water infiltration process after biochar application. Statistical analysis of main effects showed that the biochar particle size, the biochar addition amount

  14. Radiology and pathology correlation in common infiltrative cardiomyopathies

    International Nuclear Information System (INIS)

    Varzeshi, Neda; Hansen, Mark; Rezaee, Amir; Slaughter, Richard; Dixon, Natalie; Duhig, Edwina

    2012-01-01

    Infiltrative cardiomyopathies generally pose a diagnostic dilemma as current diagnostic tools are imprecise. Invasive endomyocardial biopsy is considered as the gold standard however it has some limitations. Recently cardiovascular magnetic resonance (CMR) is emerging as an excellent technique in diagnosing infiltrative cardiomyopathies and is increasingly being used. Characteristic pathologic and radiologic findings in most common infiltrative cardiomyopathies (amyloid, sarcoid and Fabry's) are discussed and correlated with relative CMR and histologic examples. There is fairly good correlation between the non-invasive radiologic and the invasive histologic findings in common infiltrative cardiomyopathies. Non-invasive CMR with its high sensitivity and specificity has an excellent role in establishing the diagnosis and improving the prognosis of common infiltrative cardiomyopathies.

  15. Interpretation of ponded infiltration data using numerical experiments

    Directory of Open Access Journals (Sweden)

    Dohnal Michal

    2016-09-01

    Full Text Available Ponded infiltration experiment is a simple test used for in-situ determination of soil hydraulic properties, particularly saturated hydraulic conductivity and sorptivity. It is known that infiltration process in natural soils is strongly affected by presence of macropores, soil layering, initial and experimental conditions etc. As a result, infiltration record encompasses a complex of mutually compensating effects that are difficult to separate from each other. Determination of sorptivity and saturated hydraulic conductivity from such infiltration data is complicated. In the present study we use numerical simulation to examine the impact of selected experimental conditions and soil profile properties on the ponded infiltration experiment results, specifically in terms of the hydraulic conductivity and sorptivity evaluation. The effect of following factors was considered: depth of ponding, ring insertion depth, initial soil water content, presence of preferential pathways, hydraulic conductivity anisotropy, soil layering, surface layer retention capacity and hydraulic conductivity, and presence of soil pipes or stones under the infiltration ring. Results were compared with a large database of infiltration curves measured at the experimental site Liz (Bohemian Forest, Czech Republic. Reasonably good agreement between simulated and observed infiltration curves was achieved by combining several of factors tested. Moreover, the ring insertion effect was recognized as one of the major causes of uncertainty in the determination of soil hydraulic parameters.

  16. Air pollutant emission rates for sources at the Davis Canyon Repository site

    International Nuclear Information System (INIS)

    1985-11-01

    This document summarizes the air-quality source terms used for the Davis Canyon, Utah environmental assessment report and explains their derivation. The engineering data supporting these source terms appear as appendixes to the report and include summary equipment lists for the repository (December, 1984) and detailed equipment lists for the exploratory shaft (June and July, 1985). Although substantial work has been performed in establishing the current repository design, a greater effort will be required for the final design. Consequently, the repository emission rates presented here should be considered as preliminary estimates. Another set of air pollutant emission rates will be calculated after design data are more firmly established. 19 refs., 18 tabs

  17. Comparison of the degree of pulpal anesthesia achieved with the intraosseous injection and infiltration injection using 2% lidocaine with 1:100,000 epinephrine.

    Science.gov (United States)

    Nusstein, John; Wood, Mark; Reader, Al; Beck, Mike; Weaver, Joel

    2005-01-01

    This prospective, randomized study compared the degree of pulpal anesthesia obtained from an intraosseous injection to an infiltration injection that used 2% lidocaine with 1:100,000 epinephrine. The success rate for the intraosseous injection was 98%; for the infiltration injection, the success rate was 85%. There was no significant difference between the two techniques. The mean time for the onset of pulpal anesthesia was significantly faster with the intraosseous injection and the infiltration injection resulted in a significantly longer duration of pulpal anesthesia.

  18. Novel Infiltration Diagnostics based on Laser-line Scanning and Infrared Temperature Field Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xinwei [Iowa State Univ., Ames, IA (United States)

    2017-12-08

    This project targets the building energy efficiency problems induced by building infiltration/leaks. The current infiltration inspection techniques often require extensive visual inspection and/or whole building pressure test. These current techniques cannot meet more than three of the below five criteria of ideal infiltration diagnostics: 1. location and extent diagnostics, 2. building-level application, 3. least surface preparation, 4. weather-proof, and 5. non-disruption to building occupants. These techniques are either too expensive or time consuming, and often lack accuracy and repeatability. They are hardly applicable to facades/facades section. The goal of the project was to develop a novel infiltration diagnostics technology based on laser line-scanning and simultaneous infrared temperature imaging. A laboratory scale experimental setup was designed to mimic a model house of well-defined pressure difference below or above the outside pressure. Algorithms and Matlab-based programs had been developed for recognition of the hole location in infrared images. Our experiment based on laser wavelengths of 450 and 1550 nm and laser beam diameters of 4-25 mm showed that the location of the holes could be identified using laser heating; the diagnostic approach however could not readily distinguish between infiltration and non-infiltration points. To significantly improve the scanning throughput and recognition accuracy, a second approach was explored, developed, and extensively tested. It incorporates a liquid spray on the surface to induce extra phase change cooling effect. In this spray method, we termed it as PECIT (Phase-change Enhanced Cooling Infrared Thermography), phase-change enhanced cooling was used, which significantly amplifies the effect of air flow (infiltration and exfiltration). This heat transfer method worked extremely well to identify infiltration and exfiltration locations with high accuracy and increased throughput. The PECIT technique was

  19. Infiltration and runoff generation processes in fire-affected soils

    Science.gov (United States)

    Moody, John A.; Ebel, Brian A.

    2014-01-01

    Post-wildfire runoff was investigated by combining field measurements and modelling of infiltration into fire-affected soils to predict time-to-start of runoff and peak runoff rate at the plot scale (1 m2). Time series of soil-water content, rainfall and runoff were measured on a hillslope burned by the 2010 Fourmile Canyon Fire west of Boulder, Colorado during cyclonic and convective rainstorms in the spring and summer of 2011. Some of the field measurements and measured soil physical properties were used to calibrate a one-dimensional post-wildfire numerical model, which was then used as a ‘virtual instrument’ to provide estimates of the saturated hydraulic conductivity and high-resolution (1 mm) estimates of the soil-water profile and water fluxes within the unsaturated zone.Field and model estimates of the wetting-front depth indicated that post-wildfire infiltration was on average confined to shallow depths less than 30 mm. Model estimates of the effective saturated hydraulic conductivity, Ks, near the soil surface ranged from 0.1 to 5.2 mm h−1. Because of the relatively small values of Ks, the time-to-start of runoff (measured from the start of rainfall),  tp, was found to depend only on the initial soil-water saturation deficit (predicted by the model) and a measured characteristic of the rainfall profile (referred to as the average rainfall acceleration, equal to the initial rate of change in rainfall intensity). An analytical model was developed from the combined results and explained 92–97% of the variance of  tp, and the numerical infiltration model explained 74–91% of the variance of the peak runoff rates. These results are from one burned site, but they strongly suggest that  tp in fire-affected soils (which often have low values of Ks) is probably controlled more by the storm profile and the initial soil-water saturation deficit than by soil hydraulic properties.

  20. On the design criteria for the evaporated water flow rate in a wet air cooler

    International Nuclear Information System (INIS)

    Bourillot, C.

    1982-01-01

    The author discusses Poppe's formulation used for the modelling of heat exchangers between air and water, in Electricite de France's TEFERI numerical wet atmospheric cooler model: heat transfer laws in unsaturated and saturated air, Bosnjakivic's formula, evaporation coefficient. The theorical results show good agreement with the measurements taken on Neurath's cooler C in West Germany, whatever the ambient temperature (evaporated water flow rate, condensate content of warm air). The author then demonstrates the inadequacy of Merkel's method for calculating evaporated water flow rates, and estimates the influence of the assumptions made on the total error [fr

  1. Seasonal Variations of Indoor Microbial Exposures and Their Relation to Temperature, Relative Humidity, and Air Exchange Rate

    DEFF Research Database (Denmark)

    Frankel, Mika; Bekö, Gabriel; Timm, Michael

    2012-01-01

    with temperature, relative humidity, and air exchange rates in Danish homes. Airborne inhalable dust was sampled in five Danish homes throughout the four seasons of 1 year (indoors, n = 127; outdoors, n = 37). Measurements included culturable fungi and bacteria, endotoxin, N-acetyl-beta-d-glucosaminidase, total...... inflammatory potential, particles (0.75 to 15 μm), temperature, relative humidity, and air exchange rates. Significant seasonal variation was found for all indoor microbial exposures, excluding endotoxin. Indoor fungi peaked in summer (median, 235 CFU/m3) and were lowest in winter (median, 26 CFU/m3). Indoor...... of inhalable dust and number of particles. Temperature and air exchange rates were positively associated with fungi and N-acetyl-beta-d-glucosaminidase and negatively with bacteria and the total inflammatory potential. Although temperature, relative humidity, and air exchange rates were significantly...

  2. Dosimetric implications of the infiltrated injection

    International Nuclear Information System (INIS)

    Castronovo, F.P.; McKusick, K.A.; Strauss, H.W.

    1984-01-01

    Following inadvertent infiltration of a radiopharmaceutical, there is variable and uncertain uptake in target tissue. Concomitantly, there is also a concern for the radiation dose to the infiltrated site. This investigation determined the clearance and radiation burdens from various radiopharmaceutical infiltrates in a rat model. Nine separate sites were studied for: Tc-99m microspheres; Tc-99m MDP; Ga-67 citrate; and Tl-201 chloride. Following sc injection on the shaven posteriors of anesthetized adult male Sprague-Dawley rats, gamma camera and computer data were collected up to 24 hours. The resulting data were expressed semilogarithmically as the mean (N = 9) of the ''% retained at site'' as a f(time) after injection. Nonparticulate agents showed a tri-exponential release pattern from each site, whereas the microspheres remained for an extended period of time. Using these pharma-cokinetic curves, the % remaining at each site for various times, and rems/mCi per lcc infiltrate was determined

  3. Stability analysis of unsaturated soil slope during rainfall infiltration using coupled liquid-gas-solid three-phase model

    Directory of Open Access Journals (Sweden)

    Dong-mei Sun

    2016-07-01

    Full Text Available Generally, most soil slope failures are induced by rainfall infiltration, a process that involves interactions between the liquid phase, gas phase, and solid skeleton in an unsaturated soil slope. In this study, a loosely coupled liquid-gas-solid three-phase model, linking two numerical codes, TOUGH2/EOS3, which is used for water-air two-phase flow analysis, and FLAC3D, which is used for mechanical analysis, was established. The model was validated through a documented water drainage experiment over a sandy column and a comparison of the results with measured data and simulated results from other researchers. The proposed model was used to investigate the features of water-air two-phase flow and stress fields in an unsaturated soil slope during rainfall infiltration. The slope stability analysis was then performed based on the simulated water-air two-phase seepage and stress fields on a given slip surface. The results show that the safety factor for the given slip surface decreases first, then increases, and later decreases until the rainfall stops. Subsequently, a sudden rise occurs. After that, the safety factor decreases continually and reaches its lowest value, and then increases slowly to a steady value. The lowest value does not occur when the rainfall stops, indicating a delayed effect of the safety factor. The variations of the safety factor for the given slip surface are therefore caused by a combination of pore-air pressure, matric suction, normal stress, and net normal stress.

  4. 40 CFR 35.927-1 - Infiltration/inflow analysis.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Infiltration/inflow analysis. 35.927-1... ASSISTANCE STATE AND LOCAL ASSISTANCE Grants for Construction of Treatment Works-Clean Water Act § 35.927-1 Infiltration/inflow analysis. (a) The infiltration/inflow analysis shall demonstrate the nonexistence or...

  5. The relation between wetting and infiltration behaviour in the Al-1010/TiC and Al-2024/TiC Systems

    International Nuclear Information System (INIS)

    Contreras, A.; Lopez, V.H.; Leon, C.A.; Bedolla, E.; Drew, R.A.A.

    2001-01-01

    Wetting and infiltration behavior of TiC by commercial aluminum (Al-1010) and Al-2024 alloy was investigated. Wettability tests were performed on dense TiC substrates (96.8% theoretical density) using a sessile drop technique in the temperature range of 850 to 1000 deg C under vacuum atmosphere. Pressureless melt infiltration of particulate TiC performs (56% theoretical density) was carried out under an inert atmosphere at temperatures ranging from 900 to 1100 deg C. Infiltration profiles were obtained using a thermogravimetric analyzer (TGA), which measured continuously the weight change of the compacts as the liquid alloy infiltrated From the wetting study, it was found that wettability of TiC by liquid Al-1010 was better than Al-2024. A strong temperature dependence was observed. Electron probe microanalysis (EPMA) indicated that aluminum carbide (Al 4 C 3 ) is formed at the interface in both metal/ceramic assemblies. In agreement with the wetting results. Al-1010 exhibited the highest infiltration rate during composite fabrication. The activation energy determined from the slopes of Arrhenius plots for the infiltration rate at the different temperatures was 172 kJ/mol and 179 kJ/mol for the Al-1010/TiC and Al-2024/TiC systems, respectively. Copyright (2000) AD-TECH - International Foundation for the Advancement of Technology Ltd

  6. Air tightness of new houses in the U.S.: A preliminary report; TOPICAL

    International Nuclear Information System (INIS)

    Sherman, Max H.; Matson, Nance E.

    2002-01-01

    Most dwellings in the United States are ventilated primarily through leaks in the building shell (i.e., infiltration) rather than by whole-house mechanical ventilation systems. Consequently, quantification of envelope air-tightness is critical to determining how much energy is being lost through infiltration and how much infiltration is contributing toward ventilation requirements. Envelope air tightness and air leakage can be determined from fan pressurization measurements with a blower door. Tens of thousands of unique fan pressurization measurements have been made of U.S. dwellings over the past decades. LBNL has collected the available data on residential infiltration into its Residential Diagnostics Database, with support from the U.S. Department of Energy. This report documents the envelope air leakage section of the LBNL database, with particular emphasis on new construction. The work reported here is an update of similar efforts carried out a decade ago, which used available data largely focused on the housing stock, rather than on new construction. The current effort emphasizes shell tightness measurements made on houses soon after they are built. These newer data come from over two dozen datasets, including over 73,000 measurements spread throughout a majority of the U.S. Roughly one-third of the measurements are for houses identified as energy-efficient through participation in a government or utility program. As a result, the characteristics reported here provide a quantitative estimate of the impact that energy-efficiency programs have on envelope tightness in the US, as well as on trends in construction

  7. Tumor-infiltrating CD8+ lymphocytes effect on clinical outcome of muco-cutaneous melanoma

    Directory of Open Access Journals (Sweden)

    Mahtab Rahbar

    2015-01-01

    Full Text Available Background: Recent data have changed our views of prognostic factors in cutaneous melanoma, while some newer methods have yielded better prognostic information. Tumor-infiltrating lymphocytes are believed to represent the immune reaction/response to melanoma cells which is often found in melanocytic cancer. Aim and Objective: We carried out an analysis, aiming to establish pooled estimates for clinical outcomes based on the presence of CD8+ T cell in melanocytic cancer. Materials and Methods: We have included 42 patients with primary cutaneous melanocytic cancer without preoperative treatments in our study. We next analyzed the proliferative activity of CD8+ T cells that infiltrated in tumor cell nests. The intratumoral and adjacent to invasive margin of tumor CD+ T-cell infiltration were analyzed which could also reflect antitumor immunity. Results: The total number of CD8+ cells especially adjacent to invasive margin of tumor was positively correlated with anatomical tumor thickness (P < .001 and not correlated with patient′s age and sex. The stage of tumor which is related to vascular-neural invasion, regional lymph nodes involvement and tumor thickness shows positive correlation with CD8+ infiltration in tumor (P < .004, P < .005, P < .001, respectively. Acral melanoma shows more CD8 lymphocytes infiltration and also recurrence rate of tumor (P < .005. Conclusion: We believe that CD8+ T-cell infiltration in primary cutaneous melanocytic cancer represents the immune reaction/response to melanoma which could be an important new therapy for melanoma although more research is needed on this treatment modality.

  8. Relationship between Microcalcification and infiltration in breast cancer

    International Nuclear Information System (INIS)

    Park, Tai Que; Jeon, Mal Soon; Kim, Yang Sook

    1990-01-01

    Microcalcification is one of the most common findings in breast cancer and most of cases with microcalcification only reveal non infiltrating type of cancer and better prognosis. We analysed 70 cases of breast cancer pathologically proved among 2,115 patients that underwent xermammography from 1983. 10.1 to 1989. 7. 30 and studied relationship between xerographic findings and nature of infiltration in breast cancer. The results were as follows: 1. Among 2,115 patients which were performed xeromammography, 70 cases were pathologically proved breast cancer and incident was 3.3%. 2. Incidence of breast cancer in terms of age was 0.2% in third decade. 1.2% in fourth decade, 4.4% in fifth decade, 14.3% in sixth decade, 15 % over seventh decade. Of total 70 patients, 51 cases were included over fifth decade. 3. Xeromammgraphy findings were classified microcalcification only, mass only, microcalcification with mass. Incidence of xerography findings such as microcalcification only (22%) was less than that of mass density (78%). 4. In 16 cases of microcalcification only. Incidence below 50 years (75%) were more than that over 50 (25%). 5. Infiltrating breast cancers (67%) were more than non-infiltrating breast cancer (33%) and number of non-infiltrating breast cancer with xerographic findings of microcalcification only (56%) was no more than that of infiltrating breast cancer (44%) but number of infiltrating breast cancer with mass (75%) was much more than non-infiltrating breast cancer (25%)

  9. Study of air and steam leak rate through damaged concrete wall

    International Nuclear Information System (INIS)

    Abdeslam Laghcha; Gerard Debicki; Benoit Masson

    2005-01-01

    Full text of publication follows: The leak rate prediction of air and steam through a cracked concrete wall is an extremely important issue in assessing the safety of nuclear reactor containment building. Furthermore the relation between air leak rate and steam leak rate on the same wall could have some interest for safety prediction. This laboratory study investigates the transfer of fluids through a wall of 1.3 m of thickness, with a focus on two cases: one on a mechanically damaged concrete by compressive stress and another one on a crossing artificial flaw in a construction joint realized in the concrete specimen (cylindrical / section 0.1925 m 2 / length 1.3 m). The both specimens were made of ordinary concrete (compressive strength: 35 MPa). To initiate residual compressive cracks, the specimen (A) was loaded in compression under controlled strains until a level of 90% of the failure strain was reached. To create a crossing artificial flaw in a construction joint, the concrete was set in the mould in two times, the second time, a water saturated sand bed was placed on the surface of the hardened concrete to realize the flaw along a diameter of the specimen (B). The permeability of damaged concrete wall was studied comparatively under two conditions, but without appreciable stresses applied on. The first condition was at ambient temperature, a reference test of permeability, with dry air, gave the characteristics of permeability and the type of flow through the specimen. In this case, the used method consisted to proceed by stages. The imposed pressures on the exposed face were successively 0.1, 0.18, 0.23, 0.28, 0.34 and 0.42 MPa, the other face was at atmospheric pressure. The second condition was an accidental scenario with simultaneous effects of temperature and gas (a mix of air and steam) pressure applied on a face, the other one remaining at atmospheric pressure and temperature. During the test, the lateral face of the cylindrical specimen was thermally

  10. Air kerma rate estimation by means of in-situ gamma spectrometry: A Bayesian approach

    International Nuclear Information System (INIS)

    Cabal, Gonzalo; Kluson, Jaroslav

    2008-01-01

    Full text: Bayesian inference is used to determine the Air Kerma Rate based on a set of in situ environmental gamma spectra measurements performed with a NaI(Tl) scintillation detector. A natural advantage of such approach is the possibility to quantify uncertainty not only in the Air Kerma Rate estimation but also for the gamma spectra which is unfolded within the procedure. The measurements were performed using a 3'' x 3'' NaI(Tl) scintillation detector. The response matrices of such detection system were calculated using a Monte Carlo code. For the calculations of the spectra as well as the Air Kerma Rate the WinBugs program was used. WinBugs is a dedicated software for Bayesian inference using Monte Carlo Markov chain methods (MCMC). The results of such calculations are shown and compared with other non-Bayesian approachs such as the Scofield-Gold iterative method and the Maximum Entropy Method

  11. Highly durable anode supported solid oxide fuel cell with an infiltrated cathode

    DEFF Research Database (Denmark)

    Samson, Alfred Junio; Hjalmarsson, Per; Søgaard, Martin

    2012-01-01

    An anode supported solid oxide fuel cell with an La0.6Sr0.4Co1.05O3_δ (LSC) infiltrated-Ce0.9Gd0.1O1.95 (CGO) cathode that shows a stable performance has been developed. The cathode was prepared by screen printing a porous CGO backbone on top of a laminated and co-fired anode supported half cell...... was tested at 700 deg. C under a current density of 0.5 A cm-2 for 1500 h using air as oxidant and humidified hydrogen as fuel. The electrochemical performance of the cell was analyzed by impedance spectroscopy and current evoltage relationships. No measurable degradation in the cell voltage or increase...... in the resistance from the recorded impedance was observed during long term testing. The power density reached 0.79Wcm-2 at a cell voltage of 0.6 V at 750 deg. C. Post test analysis of the LSC infiltrated-CGO cathode by scanning electron microscopy revealed no significant micro-structural difference...

  12. Thematic issue on soil water infiltration

    Science.gov (United States)

    Infiltration is the term applied to the process of water entry into the soil, generally by downward flow through all or part of the soil surface. Understanding of infiltration concept and processes has greatly improved, over the past 30 years, and new insights have been given into modeling of non-un...

  13. Portable radiation meters evaluation in high rates of air kerma

    International Nuclear Information System (INIS)

    Damatto, Willian B.; Potiens, Maria da Penha A.; Vivolo, Vitor

    2015-01-01

    A set of portable meters of ionizing radiation high rates of air kerma (teletectors) commonly used in emergencies in Brazil and sent to the Calibration Laboratory of IPEN were under several tests and analyst is parameters for the detectors behavior were established, specifying their sensitivities and operating characteristics. Applied tests were: reading equipment variation with battery voltage, geotropism effect, energy dependence, the angular dependence and overload. Thus it was possible to determine the most common characteristic found in these equipment (quality control programs). The behavior of 17 portable meters was analyzed and in this study, 10 of them have been tested. It was performed to characterize the gamma irradiating system (radiation dosimetry field) that possesses higher activity in teletectors for testing of larger measuring range. New calibration criteria were established following international recommendations. Therefore, it was made the improvement of the quality control programme of portable meters of ionizing radiation high rates of air kerma calibration laboratory, benefiting the users of such equipment with better consistent calibration measurements. (author)

  14. The influence of droplet evaporation on fuel-air mixing rate in a burner

    Science.gov (United States)

    Komiyama, K.; Flagan, R. C.; Heywood, J. B.

    1977-01-01

    Experiments involving combustion of a variety of hydrocarbon fuels in a simple atmospheric pressure burner were used to evaluate the role of droplet evaporation in the fuel/air mixing process in liquid fuel spray flames. Both air-assist atomization and pressure atomization processes were studied; fuel/air mixing rates were determined on the basis of cross-section average oxygen concentrations for stoichiometric overall operation. In general, it is concluded that droplets act as point sources of fuel vapor until evaporation, when the fuel jet length scale may become important in determining nonuniformities of the fuel vapor concentration. In addition, air-assist atomizers are found to have short droplet evaporation times with respect to the duration of the fuel/air mixing process, while for the pressure jet atomizer the characteristic evaporation and mixing times are similar.

  15. The effect of air bubble position after blastocyst transfer on pregnancy rates in IVF cycles.

    Science.gov (United States)

    Friedman, Brooke E; Lathi, Ruth B; Henne, Melinda B; Fisher, Stephanie L; Milki, Amin A

    2011-03-01

    To investigate the relationship between air bubble position after blastocyst transfer (BT) and pregnancy rates (PRs). Retrospective cohort study. University-based infertility center. Three hundred fifteen consecutive nondonor BTs by a single provider. Catheters were loaded with 25 μL of culture media, 20 μL of air, 25 μL of media containing the blastocysts, 20 μL of air, and a small amount of additional media. The distance from the air bubble to the fundus, as seen on abdominal ultrasound examination, was measured at the time of transfer. Air bubble location was categorized as 20 mm from the fundus. Clinical pregnancy rate. After controlling for age, parity, FSH and frozen transfers, and accounting for repeated cycles per patient, the PRs for both the >20-mm (38.3%) and the 10-20-mm (42.0%) from the fundus group were significantly reduced compared with the group in which the bubble was Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  16. The importance of determining the air exchange rate in flats and buildings for calculations of the averted indoor inhalation doses arising from contaminated outdoor air

    International Nuclear Information System (INIS)

    Jilek, Karel; Thomas, J.; Bulanek, B.; Lenk, J.; Marikova, S.

    2015-01-01

    The indoor-outdoor air exchange rate is an important parameter when refining estimates of the averted inhaled doses to population in houses and buildings after an emergency event resulting in contamination of outdoor air with a radioactive material. The air exchange rates measured in 70 occupied houses and in 20 unoccupied houses using N 2 O as the tracer gas are presented, and the results of modelling the averted doses in the residential buildings for both gaseous and aerosol outdoor contaminants are demonstrated. (orig.)

  17. Anomalous behaviors during infiltration into heterogeneous porous media

    Science.gov (United States)

    Aarão Reis, F. D. A.; Bolster, D.; Voller, V. R.

    2018-03-01

    Flow and transport in heterogeneous porous media often exhibit anomalous behavior. A physical analog example is the uni-directional infiltration of a viscous liquid into a horizontal oriented Hele-Shaw cell containing through thickness flow obstacles; a system designed to mimic a gravel/sand medium with impervious inclusions. When there are no obstacles present or the obstacles form a multi-repeating pattern, the change of the length of infiltration F with time t tends to follow a Fickian like scaling, F ∼t1/2 . In the presence of obstacle fields laid out as Sierpinski carpet fractals, infiltration is anomalous, i.e., F ∼ tn, n ≠ 1/2. Here, we study infiltration into such Hele-Shaw cells. First we investigate infiltration into a square cell containing one fractal carpet and make the observation that it is possible to generate both sub (n 1/2) diffusive behaviors within identical heterogeneity configurations. We show that this can be explained in terms of a scaling analysis developed from results of random-walk simulations in fractal obstacles; a result indicating that the nature of the domain boundary controls the exponent n of the resulting anomalous transport. Further, we investigate infiltration into a rectangular cell containing several repeats of a given Sierpinski carpet. At very early times, before the liquid encounters any obstacles, the infiltration is Fickian. When the liquid encounters the first (smallest scale) obstacle the infiltration sharply transitions to sub-diffusive. Subsequently, around the time where the liquid has sampled all of the heterogeneity length scales in the system, there is a rapid transition back to Fickian behavior. An explanation for this second transition is obtained by developing a simplified infiltration model based on the definition of a representative averaged hydraulic conductivity.

  18. Application of a water balance model for estimating deep infiltration in a karstic watershed

    Directory of Open Access Journals (Sweden)

    Maria Lúcia Calijuri

    2011-12-01

    Full Text Available The current scenario of water scarcity evidences the need for an adequate management of water resources. In karstic regions, the water flow through fractures significantly increases the water infiltration rate, which explains the small number of rivers and the importance of groundwater for urban supply. Therefore, the water balance is necessary since it may aid decision making processes and guide water management projects. The objective of this paper was to perform the water balance of a watershed situated in a karstic region quantifying infiltration, runoff and evapotranspiration. The study area is located near the Tancredo Neves International Airport in Confins, in the state of Minas Gerais, Brazil. Most of the area consists of forest formations (40.9%, and pastures (34.5%. In order to estimate deep infiltration, the BALSEQ model was used. BALSEQ is a numeric model of sequential water balance in which deep infiltration at the end of the day is given by the difference between daily precipitation and the sum of surface runoff, evapotranspiration and the variation of the amount of water stored in the soil. The results show that approximately 60% of total annual precipitation result in deep infiltration, considering the recharge period from September to March. After the dry period, the areas with no vegetal cover present higher deep infiltration. However, over the months, the contribution of the vegetated areas becomes greater, showing the importance of these areas to aquifer recharge.

  19. Tumor-infiltrating lymphocytes and ductal carcinoma in situ of the breast: friends or foes?

    Science.gov (United States)

    Agahozo, Marie Colombe; Hammerl, Dora; Debets, Reno; Kok, Marleen; van Deurzen, Carolien H M

    2018-02-20

    In the past three decades, the detection rate of ductal carcinoma in situ of the breast has dramatically increased due to breast screening programs. As a consequence, about 20% of all breast cancer cases are detected in this early in situ stage. Some ductal carcinoma in situ cases will progress to invasive breast cancer, while other cases are likely to have an indolent biological behavior. The presence of tumor-infiltrating lymphocytes is seen as a promising prognostic and predictive marker in invasive breast cancer, mainly in HER2-positive and triple-negative subtypes. Here, we summarize the current understanding regarding immune infiltrates in invasive breast cancer and highlight recent observations regarding the presence and potential clinical significance of such immune infiltrates in patients with ductal carcinoma in situ. The presence of tumor-infiltrating lymphocytes, their numbers, composition, and potential relationship with genomic status will be discussed. Finally, we propose that a combination of genetic and immune markers may better stratify ductal carcinoma in situ subtypes with respect to tumor evolution.

  20. Mechanisms of water infiltration into conical hydrophobic nanopores.

    Science.gov (United States)

    Liu, Ling; Zhao, Jianbing; Yin, Chun-Yang; Culligan, Patricia J; Chen, Xi

    2009-08-14

    Fluid channels with inclined solid walls (e.g. cone- and slit-shaped pores) have wide and promising applications in micro- and nano-engineering and science. In this paper, we use molecular dynamics (MD) simulations to investigate the mechanisms of water infiltration (adsorption) into cone-shaped nanopores made of a hydrophobic graphene sheet. When the apex angle is relatively small, an external pressure is required to initiate infiltration and the pressure should keep increasing in order to further advance the water front inside the nanopore. By enlarging the apex angle, the pressure required for sustaining infiltration can be effectively lowered. When the apex angle is sufficiently large, under ambient condition water can spontaneously infiltrate to a certain depth of the nanopore, after which an external pressure is still required to infiltrate more water molecules. The unusual involvement of both spontaneous and pressure-assisted infiltration mechanisms in the case of blunt nanocones, as well as other unique nanofluid characteristics, is explained by the Young's relation enriched with the size effects of surface tension and contact angle in the nanoscale confinement.

  1. Reuter Centrifugal Air Sampler: Measurement of Effective Airflow Rate and Collection Efficiency

    OpenAIRE

    Macher, J. M.; First, M. W.

    1983-01-01

    Incorrect calculation of effective air sampling rate and disregard of differences in collection efficiency among samplers can lead to false conclusions about the usefulness of samplers for measuring concentrations of airborne microorganisms.

  2. Experimental Air-Tightness Analysis in Mediterranean Buildings after Windows Retrofit

    Directory of Open Access Journals (Sweden)

    Francesca Romana d’Ambrosio Alfano

    2016-09-01

    Full Text Available Energy saving and Indoor Air Quality (IAQ in buildings are strongly affected by air leakages. Several studies reveal that the energy loss owing to leaky windows can account for up to 40% of the total building energy demand. Furthermore, at the design stage, the possible infiltration of outdoor air through windows is not taken into account when determining the nominal outdoor airflow rate of the ventilation system. This practice may result in an oversizing of the ventilation system and consequent energy waste. Thus, the air-tightness class of a wall assembly should be assessed for each window component considering the type of material, the presence of the seal, the type of closure, the sealing and the maintenance condition. In this paper, the authors present the experimental results of air-tightness measurements carried out using the fan pressurization method in three residential buildings located in the Mediterranean region before and after a window retrofit. Two different window retrofits were investigated: the application of rubber seals on window frames and the substitution of existing windows with new certified high performance windows. The effectiveness of such retrofits was estimated also in terms of energy saving. Test results demonstrated a high variability of the building air tightness after window retrofits, despite the fact that air tight–certified windows were used.

  3. Air pollutant emission rates for sources at the Deaf Smith County repository site

    International Nuclear Information System (INIS)

    1985-11-01

    This document summarizes the air-quality source terms used for the Deaf Smith County, Texas environmental assessment report and explains their derivation. The engineering data supporting these source terms appear as appendixes to this report and include summary equipment lists for the repository and detailed equipment lists for the exploratory shaft. Although substantial work has been performed in establishing the current repository design, a greater effort will be required for the final design. Consequently, the repository emission rates presented here should be considered as preliminary estimates. Another set of air pollution emission rates will be calculated after design data are more firmly established. 18 refs., 15 tabs

  4. Experimental and modelling studies of infiltration

    International Nuclear Information System (INIS)

    Giudici, M.

    2004-01-01

    This presentation describes a study of infiltration in the unsaturated soil with the objective of estimating the recharge to a phreatic aquifer. The study area is at the border of the city of Milan (Northern Italy), which draws water for both domestic and industrial purposes from ground water resources located beneath the urban area. The rate of water pumping from the aquifer system has been varying during the XX century, depending upon the number of inhabitants and the development of industrial activities. This caused variations with time of the depth of the water table below the ground surface and in turn some emergencies: the two most prominent episodes correspond to the middle '70s, when the water table in the city centre was about 30 m below the undisturbed natural conditions, and to the last decade, when the water table has raised at a rate of approximately 1 m/year and caused infiltrations in deep constructions (garages and building foundations, the underground railways, etc.). We have developed four ground water flow models at different scales, which share some characteristics: they are based on quasi-3D approximation (horizontal flow in the aquifers and vertical flow in the aquitards), conservative finite-differences schemes for regular grid with square cells in the horizontal plane and are implemented with proprietary computer codes. Among the problems that were studied for the development of these models, I recall some numerical problems, related to the behaviour of the phreatic aquifer under conditions of strong exploitation. Model calibration and validation for ModMil has been performed with a two-stage process, i.e., using some of the available data for model calibration and the remaining data for model validation. The application of geophysical exploration techniques, in particular seismic and geo-electrical prospecting, has been very useful to complete the data and information on the hydro-geological structure obtained from stratigraphic logs

  5. Comparing the Goodness of Different Statistical Criteria for Evaluating the Soil Water Infiltration Models

    Directory of Open Access Journals (Sweden)

    S. Mirzaee

    2016-02-01

    Full Text Available Introduction: The infiltration process is one of the most important components of the hydrologic cycle. Quantifying the infiltration water into soil is of great importance in watershed management. Prediction of flooding, erosion and pollutant transport all depends on the rate of runoff which is directly affected by the rate of infiltration. Quantification of infiltration water into soil is also necessary to determine the availability of water for crop growth and to estimate the amount of additional water needed for irrigation. Thus, an accurate model is required to estimate infiltration of water into soil. The ability of physical and empirical models in simulation of soil processes is commonly measured through comparisons of simulated and observed values. For these reasons, a large variety of indices have been proposed and used over the years in comparison of infiltration water into soil models. Among the proposed indices, some are absolute criteria such as the widely used root mean square error (RMSE, while others are relative criteria (i.e. normalized such as the Nash and Sutcliffe (1970 efficiency criterion (NSE. Selecting and using appropriate statistical criteria to evaluate and interpretation of the results for infiltration water into soil models is essential because each of the used criteria focus on specific types of errors. Also, descriptions of various goodness of fit indices or indicators including their advantages and shortcomings, and rigorous discussions on the suitability of each index are very important. The objective of this study is to compare the goodness of different statistical criteria to evaluate infiltration of water into soil models. Comparison techniques were considered to define the best models: coefficient of determination (R2, root mean square error (RMSE, efficiency criteria (NSEI and modified forms (such as NSEjI, NSESQRTI, NSElnI and NSEiI. Comparatively little work has been carried out on the meaning and

  6. Long-term dynamics of death rates of emphysema, asthma, and pneumonia and improving air quality.

    Science.gov (United States)

    Kravchenko, Julia; Akushevich, Igor; Abernethy, Amy P; Holman, Sheila; Ross, William G; Lyerly, H Kim

    2014-01-01

    The respiratory tract is a major target of exposure to air pollutants, and respiratory diseases are associated with both short- and long-term exposures. We hypothesized that improved air quality in North Carolina was associated with reduced rates of death from respiratory diseases in local populations. We analyzed the trends of emphysema, asthma, and pneumonia mortality and changes of the levels of ozone, sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and particulate matters (PM2.5 and PM10) using monthly data measurements from air-monitoring stations in North Carolina in 1993-2010. The log-linear model was used to evaluate associations between air-pollutant levels and age-adjusted death rates (per 100,000 of population) calculated for 5-year age-groups and for standard 2000 North Carolina population. The studied associations were adjusted by age group-specific smoking prevalence and seasonal fluctuations of disease-specific respiratory deaths. Decline in emphysema deaths was associated with decreasing levels of SO2 and CO in the air, decline in asthma deaths-with lower SO2, CO, and PM10 levels, and decline in pneumonia deaths-with lower levels of SO2. Sensitivity analyses were performed to study potential effects of the change from International Classification of Diseases (ICD)-9 to ICD-10 codes, the effects of air pollutants on mortality during summer and winter, the impact of approach when only the underlying causes of deaths were used, and when mortality and air-quality data were analyzed on the county level. In each case, the results of sensitivity analyses demonstrated stability. The importance of analysis of pneumonia as an underlying cause of death was also highlighted. Significant associations were observed between decreasing death rates of emphysema, asthma, and pneumonia and decreases in levels of ambient air pollutants in North Carolina.

  7. Long-term dynamics of death rates of emphysema, asthma, and pneumonia and improving air quality

    Science.gov (United States)

    Kravchenko, Julia; Akushevich, Igor; Abernethy, Amy P; Holman, Sheila; Ross, William G; Lyerly, H Kim

    2014-01-01

    Background The respiratory tract is a major target of exposure to air pollutants, and respiratory diseases are associated with both short- and long-term exposures. We hypothesized that improved air quality in North Carolina was associated with reduced rates of death from respiratory diseases in local populations. Materials and methods We analyzed the trends of emphysema, asthma, and pneumonia mortality and changes of the levels of ozone, sulfur dioxide (SO2), nitrogen dioxide (NO2), carbon monoxide (CO), and particulate matters (PM2.5 and PM10) using monthly data measurements from air-monitoring stations in North Carolina in 1993–2010. The log-linear model was used to evaluate associations between air-pollutant levels and age-adjusted death rates (per 100,000 of population) calculated for 5-year age-groups and for standard 2000 North Carolina population. The studied associations were adjusted by age group-specific smoking prevalence and seasonal fluctuations of disease-specific respiratory deaths. Results Decline in emphysema deaths was associated with decreasing levels of SO2 and CO in the air, decline in asthma deaths–with lower SO2, CO, and PM10 levels, and decline in pneumonia deaths–with lower levels of SO2. Sensitivity analyses were performed to study potential effects of the change from International Classification of Diseases (ICD)-9 to ICD-10 codes, the effects of air pollutants on mortality during summer and winter, the impact of approach when only the underlying causes of deaths were used, and when mortality and air-quality data were analyzed on the county level. In each case, the results of sensitivity analyses demonstrated stability. The importance of analysis of pneumonia as an underlying cause of death was also highlighted. Conclusion Significant associations were observed between decreasing death rates of emphysema, asthma, and pneumonia and decreases in levels of ambient air pollutants in North Carolina. PMID:25018627

  8. Efficacy of pentavalent antimoniate intralesional infiltration therapy for cutaneous leishmaniasis: A systematic review.

    Directory of Open Access Journals (Sweden)

    Nayara Castelano Brito

    Full Text Available The mainstays of cutaneous leishmaniasis (CL treatment, in several world regions, are pentavalent antimony (Sbv compounds administered parenterally, despite their recognized toxicity, which requires frequent laboratory monitoring and complicates their use in areas with scarce infrastructure. As result of these drawbacks, the WHO Expert Committee on leishmaniasis has expanded the recommendations for the use of local therapies, including Sbv intralesional infiltration (IL-Sbv, as CL therapy alternatives even in the New World. However, the efficacy of these approaches has never been compiled. The aim of this study was to critically and systematically assess the efficacy of IL-Sbv for CL treatment.The PRISMA guidelines for systematic reviews and the Cochrane manual were followed. The sources used were the MEDLINE and LILACS databases and the International Clinical Trials Registry Platform of the World Health Organization. The outcome of interest was a clinical cure, defined as complete re-epithelialization of all lesions. The IL-Sbv pooled cure rate was estimated for several subgroups and direct comparisons were performed when possible.Thirty nine articles (40 studies involving 5679 patients treated with IL-Sbv infiltration were included. In direct comparison, only three studies involving 229 patients compared IL-Sbv infiltration versus placebo and no difference was observed (OR: 1,9; 95%IC 0,93 to 3,82 based on cure rate 69.6% (95%CI 17.6-96.1% and 83,2% (95%CI 66-92.7% for placebo and IL-Sbv, respectively. In an alternative and non-comparative analysis, gathering all study arms using the intervention, the pooled IL-Sbv efficacy rate was 75% (95%CI 68-81%. In the Old World, the observed overall IL-Sbv efficacy rate was 75% (95%CI 66-82%, and the cure rates were significantly higher with sodium stibogluconate (SSG than with meglumine antimoniate (MA: 83% (95%CI 75-90% versus 68% (95%CI 54-79%, p = 0.03. Studies directly comparing IL-Sbv with topical

  9. A model for estimating time-variant rainfall infiltration as a function of antecedent surface moisture and hydrologic soil type

    Science.gov (United States)

    Wilkening, H. A.; Ragan, R. M.

    1982-01-01

    Recent research indicates that the use of remote sensing techniques for the measurement of near surface soil moisture could be practical in the not too distant future. Other research shows that infiltration rates, especially for average or frequent rainfall events, are extremely sensitive to the proper definition and consideration of the role of the soil moisture at the beginning of the rainfall. Thus, it is important that an easy to use, but theoretically sound, rainfall infiltration model be available if the anticipated remotely sensed soil moisture data is to be optimally utilized for hydrologic simulation. A series of numerical experiments with the Richards' equation for an array of conditions anticipated in watershed hydrology were used to develop functional relationships that describe temporal infiltration rates as a function of soil type and initial moisture conditions.

  10. Transcatheter arterial Chemoembolization for infiltrative hepatocellular carcinoma: Clinical safety and efficacy and factors influencing patient survival

    International Nuclear Information System (INIS)

    Han, Kichang; Kim, Jin Hyoung; Yoon, Hee Mang; Kim, Eun Joung; Gwon, Dong Il; Ko, Gi Young; Yoon, Hyun Ki; Ko, Heung Kyu

    2014-01-01

    To evaluate the safety and efficacy of transcatheter arterial chemoembolization (TACE) in patients with infiltrative hepatocellular carcinoma (HCC) and to identify the prognostic factors associated with patient survival. Fifty two patients who underwent TACE for infiltrative HCC were evaluated between 2007 and 2010. The maximum diameter of the tumors ranged from 7 cm to 22 cm (median 15 cm). Of 46 infiltrative HCC patients with portal vein tumor thrombosis, 32 patients received adjuvant radiation therapy for portal vein tumor thrombosis after TACE. The tumor response by European Association for the Study of the Liver criteria was partial in 18%, stable in 47%, and progressive in 35% of the patients. The median survival time was 5.7 months (Kaplan-Meier analysis). The survival rates were 48% at six months, 25% at one year, and 12% at two years. In the multivariable Cox regression analysis, Child-Pugh class (p = 0.02), adjuvant radiotherapy (p 0.003) and tumor response after TACE (p = 0.004) were significant factors associated with patient survival. Major complications occurred in nine patients. The major complication rate was significantly higher in patients with Child-Pugh B than in patients with Child-Pugh A (p = 0.049, x 2 test). Transcatheter arterial chemoembolization can be a safe treatment option in infiltrative HCC patients with Child Pugh class A. Child Pugh class A, radiotherapy for portal vein tumor thrombosis after TACE and tumor response are good prognostic factors for an increased survival after TACE in patients with infiltrative HCCs.

  11. Management of white spots: resin infiltration technique and microabrasion

    Directory of Open Access Journals (Sweden)

    Jeong-Hye Son

    2011-01-01

    Full Text Available This case report compared the effectiveness of resin infiltration technique (Icon, DMG with microabrasion (Opalustre, Ultradent Products, Inc. in management of white spot lesions. It demonstrates that although neither microabrasion nor resin infiltration technique can remove white spot lesions completely, resin infiltration technique seems to be more effective than microabrasion. Therefore resin infiltration technique can be chosen preferentially for management of white spot lesions and caution should be taken for case selection.

  12. Effects of hyperbaric oxygen at 1.25 atmospheres absolute with normal air on macrophage number and infiltration during rat skeletal muscle regeneration.

    Directory of Open Access Journals (Sweden)

    Naoto Fujita

    Full Text Available Use of mild hyperbaric oxygen less than 2 atmospheres absolute (2026.54 hPa with normal air is emerging as a common complementary treatment for severe muscle injury. Although hyperbaric oxygen at over 2 atmospheres absolute with 100% O2 promotes healing of skeletal muscle injury, it is not clear whether mild hyperbaric oxygen is equally effective. The purpose of the present study was to investigate the impact of hyperbaric oxygen at 1.25 atmospheres absolute (1266.59 hPa with normal air on muscle regeneration. The tibialis anterior muscle of male Wistar rats was injured by injection of bupivacaine hydrochloride, and rats were randomly assigned to a hyperbaric oxygen experimental group or to a non-hyperbaric oxygen control group. Immediately after the injection, rats were exposed to hyperbaric oxygen, and the treatment was continued for 28 days. The cross-sectional area of centrally nucleated muscle fibers was significantly larger in rats exposed to hyperbaric oxygen than in controls 5 and 7 days after injury. The number of CD68- or CD68- and CD206-positive cells was significantly higher in rats exposed to hyperbaric oxygen than in controls 24 h after injury. Additionally, tumor necrosis factor-α and interleukin-10 mRNA expression levels were significantly higher in rats exposed to hyperbaric oxygen than in controls 24 h after injury. The number of Pax7- and MyoD- or MyoD- and myogenin-positive nuclei per mm2 and the expression levels of these proteins were significantly higher in rats exposed to hyperbaric oxygen than in controls 5 days after injury. These results suggest that mild hyperbaric oxygen promotes skeletal muscle regeneration in the early phase after injury, possibly due to reduced hypoxic conditions leading to accelerated macrophage infiltration and phenotype transition. In conclusion, mild hyperbaric oxygen less than 2 atmospheres absolute with normal air is an appropriate support therapy for severe muscle injuries.

  13. CT imaging spectrum of infiltrative renal diseases.

    Science.gov (United States)

    Ballard, David H; De Alba, Luis; Migliaro, Matias; Previgliano, Carlos H; Sangster, Guillermo P

    2017-11-01

    Most renal lesions replace the renal parenchyma as a focal space-occupying mass with borders distinguishing the mass from normal parenchyma. However, some renal lesions exhibit interstitial infiltration-a process that permeates the renal parenchyma by using the normal renal architecture for growth. These infiltrative lesions frequently show nonspecific patterns that lead to little or no contour deformity and have ill-defined borders on CT, making detection and diagnosis challenging. The purpose of this pictorial essay is to describe the CT imaging findings of various conditions that may manifest as infiltrative renal lesions.

  14. Enhanced wet air oxidation : synergistic rate acceleration upon effluent recirculation

    Science.gov (United States)

    Matthew J. Birchmeier; Charles G. Hill; Carl J. Houtman; Rajai H. Atalla; Ira A. Weinstock

    2000-01-01

    Wet air oxidation (WAO) reactions of cellobiose, phenol, and syringic acid were carried out under mild conditions (155°C; 0.93MPa 02; soluble catalyst, Na5[PV2Mo10O40]). Initial oxidation rates were rapid but decreased to small values as less reactive oxidation products accumulated. Recalcitrant oxidation products were consumed more rapidly, however, if additional...

  15. Verification of a 1-dimensional model for predicting shallow infiltration at Yucca Mountain

    International Nuclear Information System (INIS)

    Hevesi, J.A.; Flint, A.L.; Flint, L.E.

    1994-01-01

    A characterization of net infiltration rates is needed for site-scale evaluation of groundwater flow at Yucca Mountain, Nevada. Shallow infiltration caused by precipitation may be a potential source of net infiltration. A 1-dimensional finite difference model of shallow infiltration with a moisture-dependant evapotranspiration function and a hypothetical root-zone was calibrated and verified using measured water content profiles, measured precipitation, and estimated potential evapotranspiration. Monthly water content profiles obtained from January 1990 through October 1993 were measured by geophysical logging of 3 boreholes located in the alluvium channel of Pagany Wash on Yucca Mountain. The profiles indicated seasonal wetting and drying of the alluvium in response to winter season precipitation and summer season evapotranspiration above a depth of 2.5 meters. A gradual drying trend below a depth of 2.5 meters was interpreted as long-term redistribution and/or evapotranspiration following a deep infiltration event caused by runoff in Pagany Wash during 1984. An initial model, calibrated using the 1990 to 1 992 record, did not provide a satisfactory prediction of water content profiles measured in 1993 following a relatively wet winter season. A re-calibrated model using a modified, seasonally-dependent evapotranspiration function provided an improved fit to the total record. The new model provided a satisfactory verification using water content changes measured at a distance of 6 meters from the calibration site, but was less satisfactory in predicting changes at a distance of 18 meters

  16. Verification of a 1-dimensional model for predicting shallow infiltration at Yucca Mountain

    International Nuclear Information System (INIS)

    Hevesi, J.; Flint, A.L.; Flint, L.E.

    1994-01-01

    A characterization of net infiltration rates is needed for site-scale evaluation of groundwater flow at Yucca Mountain, Nevada. Shallow infiltration caused by precipitation may be a potential source of net infiltration. A 1-dimensional finite difference model of shallow infiltration with a moisture-dependent evapotranspiration function and a hypothetical root-zone was calibrated and verified using measured water content profiles, measured precipitation, and estimated potential evapotranspiration. Monthly water content profiles obtained from January 1990 through October 1993 were measured by geophysical logging of 3 boreholes located in the alluvium channel of Pagany Wash on Yucca Mountain. The profiles indicated seasonal wetting and drying of the alluvium in response to winter season precipitation and summer season evapotranspiration above a depth of 2.5 meters. A gradual drying trend below a depth of 2.5 meters was interpreted as long-term redistribution and/or evapotranspiration following a deep infiltration event caused by runoff in Pagany Wash during 1984. An initial model, calibrated using the 1990 to 1992 record, did not provide a satisfactory prediction of water content profiles measured in 1993 following a relatively wet winter season. A re-calibrated model using a modified, seasonally-dependent evapotranspiration function provided an improved fit to the total record. The new model provided a satisfactory verification using water content changes measured at a distance of 6 meters from the calibration site, but was less satisfactory in predicting changes at a distance of 18 meters

  17. Reactive Melt Infiltration Of Silicon Into Porous Carbon

    Science.gov (United States)

    Behrendt, Donald R.; Singh, Mrityunjay

    1994-01-01

    Report describes study of synthesis of silicon carbide and related ceramics by reactive melt infiltration of silicon and silicon/molybdenum alloys into porous carbon preforms. Reactive melt infiltration has potential for making components in nearly net shape, performed in less time and at lower temperature. Object of study to determine effect of initial pore volume fraction, pore size, and infiltration material on quality of resultant product.

  18. Relationship between recycling rate and air pollution: Waste management in the state of Massachusetts

    International Nuclear Information System (INIS)

    Giovanis, Eleftherios

    2015-01-01

    Highlights: • This study examines the relationship between recycling rate of solid waste and air pollution. • Fixed effects Stochastic Frontier Analysis model with panel data are employed. • The case study is a waste municipality survey in the state of Massachusetts during 2009–2012. • The findings support that a negative relationship between air pollution and recycling. - Abstract: This study examines the relationship between recycling rate of solid waste and air pollution using data from a waste municipality survey in the state of Massachusetts during the period 2009–2012. Two econometric approaches are applied. The first approach is a fixed effects model, while the second is a Stochastic Frontier Analysis (SFA) with fixed effects model. The advantage of the first approach is the ability of controlling for stable time invariant characteristics of the municipalities, thereby eliminating potentially large sources of bias. The second approach is applied in order to estimate the technical efficiency and rank of each municipality accordingly. The regressions control for various demographic, economic and recycling services, such as income per capita, population density, unemployment, trash services, Pay-as-you-throw (PAYT) program and meteorological data. The findings support that a negative relationship between particulate particles in the air 2.5 μm or less in size (PM 2.5 ) and recycling rate is presented. In addition, the pollution is increased with increases on income per capita up to $23,000–$26,000, while after this point income contributes positively on air quality. Finally, based on the efficiency derived by the Stochastic Frontier Analysis (SFA) model, the municipalities which provide both drop off and curbside services for trash, food and yard waste and the PAYT program present better performance regarding the air quality

  19. Relationship between recycling rate and air pollution: Waste management in the state of Massachusetts

    Energy Technology Data Exchange (ETDEWEB)

    Giovanis, Eleftherios, E-mail: giovanis95@gmail.com

    2015-06-15

    Highlights: • This study examines the relationship between recycling rate of solid waste and air pollution. • Fixed effects Stochastic Frontier Analysis model with panel data are employed. • The case study is a waste municipality survey in the state of Massachusetts during 2009–2012. • The findings support that a negative relationship between air pollution and recycling. - Abstract: This study examines the relationship between recycling rate of solid waste and air pollution using data from a waste municipality survey in the state of Massachusetts during the period 2009–2012. Two econometric approaches are applied. The first approach is a fixed effects model, while the second is a Stochastic Frontier Analysis (SFA) with fixed effects model. The advantage of the first approach is the ability of controlling for stable time invariant characteristics of the municipalities, thereby eliminating potentially large sources of bias. The second approach is applied in order to estimate the technical efficiency and rank of each municipality accordingly. The regressions control for various demographic, economic and recycling services, such as income per capita, population density, unemployment, trash services, Pay-as-you-throw (PAYT) program and meteorological data. The findings support that a negative relationship between particulate particles in the air 2.5 μm or less in size (PM{sub 2.5}) and recycling rate is presented. In addition, the pollution is increased with increases on income per capita up to $23,000–$26,000, while after this point income contributes positively on air quality. Finally, based on the efficiency derived by the Stochastic Frontier Analysis (SFA) model, the municipalities which provide both drop off and curbside services for trash, food and yard waste and the PAYT program present better performance regarding the air quality.

  20. Mobilization of microspheres from a fractured soil during intermittent infiltration events

    Science.gov (United States)

    Mohanty, Sanjay; Bulicek, Mark; Metge, David W.; Harvey, Ronald W.; Ryan, Joseph N.; Boehm, Alexandria B.

    2015-01-01

    Pathogens or biocolloids mobilized in the vadose zone may consequently contaminate groundwater. We found that microspheres were mobilized from a fractured soil during intermittent rainfall and the mobilization was greater when the microsphere size was larger and when the soil had greater water permeability.The vadose zone filters pathogenic microbes from infiltrating water and consequently protects the groundwater from possible contamination. In some cases, however, the deposited microbes may be mobilized during rainfall and migrate into the groundwater. We examined the mobilization of microspheres, surrogates for microbes, in an intact core of a fractured soil by intermittent simulated rainfall. Fluorescent polystyrene microspheres of two sizes (0.5 and 1.8 mm) and Br− were first applied to the core to deposit the microspheres, and then the core was subjected to three intermittent infiltration events to mobilize the deposited microspheres. Collecting effluent samples through a 19-port sampler at the base of the core, we found that water flowed through only five ports, and the flow rates varied among the ports by a factor of 12. These results suggest that flow paths leading to the ports had different permeabilities, partly due to macropores. Although 40 to 69% of injected microspheres were retained in the core during their application, 12 to 30% of the retained microspheres were mobilized during three intermittent infiltration events. The extent of microsphere mobilization was greater in flow paths with greater permeability, which indicates that macropores could enhance colloid mobilization during intermittent infiltration events. In all ports, the 1.8-mm microspheres were mobilized to a greater extent than the 0.5-mm microspheres, suggesting that larger colloids are more likely to mobilize. These results are useful in assessing the potential of pathogen mobilization and colloid-facilitated transport of contaminants in the subsurface under natural infiltration

  1. The effects of air pollutants on the mortality rate of lung cancer and leukemia.

    Science.gov (United States)

    Dehghani, Mansooreh; Keshtgar, Laila; Javaheri, Mohammad Reza; Derakhshan, Zahra; Oliveri Conti, Gea; Zuccarello, Pietro; Ferrante, Margherita

    2017-05-01

    World Health Organization classifies air pollution as the first cause of human cancer. The present study investigated impact of air pollutants on the mortality rates of lung cancer and leukemia in Shiraz, one of the largests cities of Iran. This cross‑sectional (longitudinal) study was carried out in Shiraz. Data on six main pollutants, CO, SO2, O3, NO2, PM10 and PM2.5, were collected from Fars Environmental Protection Agency for 3,001 days starting from 1 January, 2005. Also, measures of climatic factors (temperature, humidity, and air pressure) were obtained from Shiraz Meteorological Organization. Finally, data related to number of deaths due to lung and blood cancers (leukemia) were gathered from Shiraz University Hospital. Relationship between variations of pollutant concentrations and cancers in lung and blood was investigated using statistical software R and MiniTab to perform time series analysis. Results of the present study revealed that the mortality rate of leukemia had a direct significant correlation with concentrations of nitrogen dioxide and carbon monoxide in the air (Pcar sharing.

  2. Modeling a ponded infiltration experiment at Yucca Mountain, NV

    International Nuclear Information System (INIS)

    Hudson, D.B.; Guertal, W.R.; Flint, A.L.

    1994-01-01

    Yucca Mountain, Nevada is being evaluated as a potential site for a geologic repository for high level radioactive waste. As part of the site characterization activities at Yucca Mountain, a field-scale ponded infiltration experiment was done to help characterize the hydraulic and infiltration properties of a layered dessert alluvium deposit. Calcium carbonate accumulation and cementation, heterogeneous layered profiles, high evapotranspiration, low precipitation, and rocky soil make the surface difficult to characterize.The effects of the strong morphological horizonation on the infiltration processes, the suitability of measured hydraulic properties, and the usefulness of ponded infiltration experiments in site characterization work were of interest. One-dimensional and two-dimensional radial flow numerical models were used to help interpret the results of the ponding experiment. The objective of this study was to evaluate the results of a ponded infiltration experiment done around borehole UE25 UZN number-sign 85 (N85) at Yucca Mountain, NV. The effects of morphological horizons on the infiltration processes, lateral flow, and measured soil hydaulic properties were studied. The evaluation was done by numerically modeling the results of a field ponded infiltration experiment. A comparison the experimental results and the modeled results was used to qualitatively indicate the degree to which infiltration processes and the hydaulic properties are understood. Results of the field characterization, soil characterization, borehole geophysics, and the ponding experiment are presented in a companion paper

  3. MO-D-213-07: RadShield: Semi- Automated Calculation of Air Kerma Rate and Barrier Thickness

    International Nuclear Information System (INIS)

    DeLorenzo, M; Wu, D; Rutel, I; Yang, K

    2015-01-01

    Purpose: To develop the first Java-based semi-automated calculation program intended to aid professional radiation shielding design. Air-kerma rate and barrier thickness calculations are performed by implementing NCRP Report 147 formalism into a Graphical User Interface (GUI). The ultimate aim of this newly created software package is to reduce errors and improve radiographic and fluoroscopic room designs over manual approaches. Methods: Floor plans are first imported as images into the RadShield software program. These plans serve as templates for drawing barriers, occupied regions and x-ray tube locations. We have implemented sub-GUIs that allow the specification in regions and equipment for occupancy factors, design goals, number of patients, primary beam directions, source-to-patient distances and workload distributions. Once the user enters the above parameters, the program automatically calculates air-kerma rate at sampled points beyond all barriers. For each sample point, a corresponding minimum barrier thickness is calculated to meet the design goal. RadShield allows control over preshielding, sample point location and material types. Results: A functional GUI package was developed and tested. Examination of sample walls and source distributions yields a maximum percent difference of less than 0.1% between hand-calculated air-kerma rates and RadShield. Conclusion: The initial results demonstrated that RadShield calculates air-kerma rates and required barrier thicknesses with reliable accuracy and can be used to make radiation shielding design more efficient and accurate. This newly developed approach differs from conventional calculation methods in that it finds air-kerma rates and thickness requirements for many points outside the barriers, stores the information and selects the largest value needed to comply with NCRP Report 147 design goals. Floor plans, parameters, designs and reports can be saved and accessed later for modification and recalculation

  4. MO-D-213-07: RadShield: Semi- Automated Calculation of Air Kerma Rate and Barrier Thickness

    Energy Technology Data Exchange (ETDEWEB)

    DeLorenzo, M [Oklahoma University Health Sciences Center, Oklahoma City, OK (United States); Wu, D [University of Oklahoma Health Sciences Center, Oklahoma City, Ok (United States); Rutel, I [University of Oklahoma Health Science Center, Oklahoma City, OK (United States); Yang, K [Massachusetts General Hospital, Boston, MA (United States)

    2015-06-15

    Purpose: To develop the first Java-based semi-automated calculation program intended to aid professional radiation shielding design. Air-kerma rate and barrier thickness calculations are performed by implementing NCRP Report 147 formalism into a Graphical User Interface (GUI). The ultimate aim of this newly created software package is to reduce errors and improve radiographic and fluoroscopic room designs over manual approaches. Methods: Floor plans are first imported as images into the RadShield software program. These plans serve as templates for drawing barriers, occupied regions and x-ray tube locations. We have implemented sub-GUIs that allow the specification in regions and equipment for occupancy factors, design goals, number of patients, primary beam directions, source-to-patient distances and workload distributions. Once the user enters the above parameters, the program automatically calculates air-kerma rate at sampled points beyond all barriers. For each sample point, a corresponding minimum barrier thickness is calculated to meet the design goal. RadShield allows control over preshielding, sample point location and material types. Results: A functional GUI package was developed and tested. Examination of sample walls and source distributions yields a maximum percent difference of less than 0.1% between hand-calculated air-kerma rates and RadShield. Conclusion: The initial results demonstrated that RadShield calculates air-kerma rates and required barrier thicknesses with reliable accuracy and can be used to make radiation shielding design more efficient and accurate. This newly developed approach differs from conventional calculation methods in that it finds air-kerma rates and thickness requirements for many points outside the barriers, stores the information and selects the largest value needed to comply with NCRP Report 147 design goals. Floor plans, parameters, designs and reports can be saved and accessed later for modification and recalculation

  5. Use of Thermal Data to Estimate Infiltration in Pagany Wash Associated with the winter of 1997-1998 El Nino Precipitation, Yucca Mountain, Nevada

    International Nuclear Information System (INIS)

    LeCain, G.D.; Lu, N.; Kurzmack, M.

    2000-01-01

    Temperature and air-pressure monitoring in a vertical borehole located in Pagany Wash, a normally dry stream-carved channel northeast of Yucca Mountain, Nevada, indicated that the annual temperature wave was measurable to a depth of 11.1 m. Temperature depressions were measured at depths of 3.1, 6.1, 9.2, and 11.1 m below ground surface. The temperature depressions were interpreted to be the result of infiltration associated with the 1997-1998 El Nino precipitation. A pressure differential, of approximately 2 kiloPascals, between stations located 11.1 and 24.5 m below ground surface was interpreted to be the result of compressed air ahead of the wetting front. The pressure differences between stations indicated that the wetting front migrated deeper than 35.2 m and that the Yucca Mountain Tuff retarded the downward movement of the wetting front. An analytical method indicated that the infiltration flux through the Pagany Wash alluvium due to the 1997-1998 El Nino precipitation was approximately 940 mm. A one-dimensional numerical model indicated that the infiltration flux was approximately 1000 mm. Sensitivity analysis indicated that the potential temperature decrease due to conduction was minimal and that cooler surface temperatures could not account for the measured subsurface temperature depressions

  6. Analysis of the wind data and estimation of the resultant air concentration rates

    International Nuclear Information System (INIS)

    Hu, Shze Jer; Katagiri, Hiroshi; Kobayashi, Hideo

    1988-09-01

    Statistical analyses and comparisons of the meteorological wind data obtained by the propeller and supersonic anemometers for the year of 1987 in the Japan Atomic Energy Research Institute, Tokai, were performed. For wind speeds less than 1 m/s, the propeller readings are generally 0.5 m/s less than those of the supersonic readings. The resultant average air concentration and ground level γ exposure rates due to the radioactive releases for the normal operation of a nuclear plant are over-estimated when calculated using the propeller wind data. As supersonic anemometer can give accurate wind speed to as low as 0.01 m/s, it should be used to measure the low wind speed. The difference in the average air concentrations and γ exposure rates calculated using the two different sets of wind data, is due to the influence of low wind speeds at calm. If the number at calm is large, actual low wind speeds and wind directions should be used in the statistical analysis of atmospheric dispersion to give a more accurate and realistic estimation of the air concentrations and γ exposure rates due to the normal operation of a nuclear plant. (author). 4 refs, 3 figs, 9 tabs

  7. Measuring the relative extent of pulmonary infiltrates by hierarchical classification of patient-specific image features

    Science.gov (United States)

    Tsevas, S.; Iakovidis, D. K.

    2011-11-01

    Pulmonary infiltrates are common radiological findings indicating the filling of airspaces with fluid, inflammatory exudates, or cells. They are most common in cases of pneumonia, acute respiratory syndrome, atelectasis, pulmonary oedema and haemorrhage, whereas their extent is usually correlated with the extent or the severity of the underlying disease. In this paper we propose a novel pattern recognition framework for the measurement of the extent of pulmonary infiltrates in routine chest radiographs. The proposed framework follows a hierarchical approach to the assessment of image content. It includes the following: (a) sampling of the lung fields; (b) extraction of patient-specific grey-level histogram signatures from each sample; (c) classification of the extracted signatures into classes representing normal lung parenchyma and pulmonary infiltrates; (d) the samples for which the probability of belonging to one of the two classes does not reach an acceptable level are rejected and classified according to their textural content; (e) merging of the classification results of the two classification stages. The proposed framework has been evaluated on real radiographic images with pulmonary infiltrates caused by bacterial infections. The results show that accurate measurements of the infiltration areas can be obtained with respect to each lung field area. The average measurement error rate on the considered dataset reached 9.7% ± 1.0%.

  8. Tempts to determine radon entry rate and air exchange rate variable in time from the time course of indoor radon concentration

    International Nuclear Information System (INIS)

    Thomas, J.

    1996-01-01

    For the study and explanation of the diurnal variability of the indoor radon concentration a(t) [Bq/m 3 ], which is proportional to the ratio of the radon entry rate A [Bq/h] and the air exchange rate k [1/h], it would be of advantage to know separately the diurnal variability of both determining quantities A(t) and k(t). To measure directly and continuously the radon entry rate A(t) is possible only in special studies (mostly in experimental rooms) and also continuous measuring of the air exchange rate k(t) is possible also only in special studies for a short time. But continuously measuring radon meters are now common, do not trouble people in normal living regime during day and night. The goal of this endeavour would be the evaluation of the time courses of both determining quantities from the time courses of the indoor radon concentration directly without additional experimental work and so a better utilisation of such measurements. (author)

  9. Infiltration with lidocaine and adrenaline instead of normal saline does not improve the septoplasty procedure.

    Science.gov (United States)

    Gungor, Volkan; Baklaci, Deniz; Kum, Rauf Oguzhan; Yilmaz, Yavuz Fuat; Ozcan, Muge; Unal, Adnan

    2016-08-01

    The aim of this study was to determine whether infiltration of local anesthetics with adrenaline improved septoplasty procedure when compared to normal saline. Eight-two patients undergoing septoplasty were randomized into two groups. In group 1, septal mucoperichondrium was infiltrated with lidocaine with adrenaline, and normal saline was used in group 2. Presence of intra-operative septal mucosal injuries, the amount of bleeding, arterial blood pressure, operation time as well as the quality of the surgical field and the convenience of finding the correct surgical plane as determined by the surgeon using a 5-point scale were compared between two groups. There were no significant differences for the amount of blood loss, mean arterial pressure, operation time, or scores for convenience of finding the correct surgical plane between the two groups. There was no significant difference for intra-operative simple (P = 0.631) and total (simple+severe) (P = 0.649) septal mucoperichondrial injuries between groups 1 and 2, either. However, severe mucoperichondrial injury rate was higher in the patients infiltrated with lidocaine and adrenaline (P = 0.026), and the quality of the surgical field was worse in the patients injected with normal saline (P = 0.0179). Infiltration of septal mucoperichondrium with lidocaine and adrenaline instead of normal saline was not advantageous in terms of objective parameters tested, including bleeding amount and duration of surgery as well as the of the total mucosal injury rate in septoplasty procedure.

  10. Examining Reliability and Validity of an Online Score (ALiEM AIR) for Rating Free Open Access Medical Education Resources.

    Science.gov (United States)

    Chan, Teresa Man-Yee; Grock, Andrew; Paddock, Michael; Kulasegaram, Kulamakan; Yarris, Lalena M; Lin, Michelle

    2016-12-01

    Since 2014, Academic Life in Emergency Medicine (ALiEM) has used the Approved Instructional Resources (AIR) score to critically appraise online content. The primary goals of this study are to determine the interrater reliability (IRR) of the ALiEM AIR rating score and determine its correlation with expert educator gestalt. We also determine the minimum number of educator-raters needed to achieve acceptable reliability. Eight educators each rated 83 online educational posts with the ALiEM AIR scale. Items include accuracy, usage of evidence-based medicine, referencing, utility, and the Best Evidence in Emergency Medicine rating score. A generalizability study was conducted to determine IRR and rating variance contributions of facets such as rater, blogs, posts, and topic. A randomized selection of 40 blog posts previously rated through ALiEM AIR was then rated again by a blinded group of expert medical educators according to their gestalt. Their gestalt impression was subsequently correlated with the ALiEM AIR score. The IRR for the ALiEM AIR rating scale was 0.81 during the 6-month pilot period. Decision studies showed that at least 9 raters were required to achieve this reliability. Spearman correlations between mean AIR score and the mean expert gestalt ratings were 0.40 for recommendation for learners and 0.35 for their colleagues. The ALiEM AIR scale is a moderately to highly reliable, 5-question tool when used by medical educators for rating online resources. The score displays a fair correlation with expert educator gestalt in regard to the quality of the resources. The score displays a fair correlation with educator gestalt. Copyright © 2016 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.

  11. VOLATILIZATION RATES FROM WATER TO INDOOR AIR ...

    Science.gov (United States)

    Contaminated water can lead to volatilization of chemicals to residential indoor air. Previous research has focused on only one source (shower stalls) and has been limited to chemicals in which gas-phase resistance to mass transfer is of marginal significance. As a result, attempts to extrapolate chemical emissions from high-volatility chemicals to lower volatility chemicals, or to sources other than showers, have been difficult or impossible. This study involved the development of two-phase, dynamic mass balance models for estimating chemical emissions from washing machines, dishwashers, and bathtubs. An existing model was adopted for showers only. Each model required the use of source- and chemical-specific mass transfer coefficients. Air exchange (ventilation) rates were required for dishwashers and washing machines as well. These parameters were estimated based on a series of 113 experiments involving 5 tracer chemicals (acetone, ethyl acetate, toluene, ethylbenzene, and cyclohexane) and 4 sources (showers, bathtubs, washing machines, and dishwashers). Each set of experiments led to the determination of chemical stripping efficiencies and mass transfer coefficients (overall, liquid-phase, gas-phase), and to an assessment of the importance of gas- phase resistance to mass transfer. Stripping efficiencies ranged from 6.3% to 80% for showers, 2.6% to 69% for bathtubs, 18% to 100% for dishwashers, and 3.8% to 100% for washing machines. Acetone and cyclohexane al

  12. Creep-behavior of different SiC-materials in vacuum and in air

    International Nuclear Information System (INIS)

    Schnuerer, K.

    1979-10-01

    Creep data under 4-point loading conditions of two hot-pressed SiC-materials with different amounts of aluminium in the SiC powder and of two reaction-sintered and silicon-infiltrated materials with different amounts of free silicon are presented. Creep tests in vacuum and also in air are performed in a temperature range from 1273 K up to 1973 K and in a stress range from 100MN/m 2 to 190MN/m 2 . For the hot-pressed SiC a stress exponent of n = 1 and activation energies of 363kJ/mol and 386kJ/mol have been found by temperature and stress change tests in vacuum. From these data one can conclude that Coble-creep is the rate-controlling process. A measurable creep-rate can be observed at temperatures above 1673 K. On the opposite a creep-rate in vacuum for Si-infiltrated SiC is measurable at temperatures already below 1273 K. TEN-observation of this materials show the presence of a second phase at grain-boundaries (silicon), thus an influence of free silicon on creep can be deduced. Besides that, a stress dependence on stress exponent can be seen for one of the reaction-sintered materials. This is referred to the activity of dislocations. (orig./RW) [de

  13. Preliminary estimates of spatially distributed net infiltration and recharge for the Death Valley region, Nevada-California

    International Nuclear Information System (INIS)

    Hevesi, J.A.; Flint, A.L.; Flint, L.E.

    2002-01-01

    A three-dimensional ground-water flow model has been developed to evaluate the Death Valley regional flow system, which includes ground water beneath the Nevada Test Site. Estimates of spatially distributed net infiltration and recharge are needed to define upper boundary conditions. This study presents a preliminary application of a conceptual and numerical model of net infiltration. The model was developed in studies at Yucca Mountain, Nevada, which is located in the approximate center of the Death Valley ground-water flow system. The conceptual model describes the effects of precipitation, runoff, evapotranspiration, and redistribution of water in the shallow unsaturated zone on predicted rates of net infiltration; precipitation and soil depth are the two most significant variables. The conceptual model was tested using a preliminary numerical model based on energy- and water-balance calculations. Daily precipitation for 1980 through 1995, averaging 202 millimeters per year over the 39,556 square kilometers area of the ground-water flow model, was input to the numerical model to simulate net infiltration ranging from zero for a soil thickness greater than 6 meters to over 350 millimeters per year for thin soils at high elevations in the Spring Mountains overlying permeable bedrock. Estimated average net infiltration over the entire ground-water flow model domain is 7.8 millimeters per year. To evaluate the application of the net-infiltration model developed on a local scale at Yucca Mountain, to net-infiltration estimates representing the magnitude and distribution of recharge on a regional scale, the net-infiltration results were compared with recharge estimates obtained using empirical methods. Comparison of model results with previous estimates of basinwide recharge suggests that the net-infiltration estimates obtained using this model may overestimate recharge because of uncertainty in modeled precipitation, bedrock permeability, and soil properties for

  14. Infiltration of surface mined land reclaimed by deep tillage treatments

    International Nuclear Information System (INIS)

    Chong, S.K.; Cowsert, P.

    1994-01-01

    Surface mining of coal leads to the drastic disturbance of soils. Compaction of replaced subsoil and topsoil resulting from hauling, grading, and leveling procedures produces a poor rooting medium for crop growth. Soil compaction results in high bulk density, low macroporosity, poor water infiltration capacity, and reduced elongation of plant roots. In the United States, Public Law 95-87 mandates that the rooting medium of mined soils have specific textural characteristics and be graded and shaped to a topography similar to premining conditions. Also, crop productivity levels equivalent to those prior to mining must be achieved, especially for prime farmland. Alleviation of compaction has been the major focus of reclamation, and recently new techniques to augment the rooting zone with deep-ripping and loosening equipment have come to the forefront. Several surface mine operators in the Illinois coal basin are using deep tillage equipment that is capable of loosening soils to greater depths than is possible with conventional farm tillage equipment. Information on the beneficial effects of these loosening procedures on soil hydrological properties, such as infiltration, runoff potential, erosion, and water retention, is extremely important for future mined land management. However, such information is lacking. In view of the current yield demonstration regulation for prime farmland and other unmined soils, it is important that as much information as possible be obtained concerning the effect of deep tillage on soil hydrologic properties. The objectives of this study are: (1) to compare infiltration rates and related soil physical properties of mined soils reclaimed by various deep tillage treatments and (2) to study the temporal variability of infiltration and related physical properties of the reclaimed mined soil after deep tillage treatment

  15. Difficulties in the evaluation and measuring of soil water infiltration

    Science.gov (United States)

    Pla-Sentís, Ildefonso

    2013-04-01

    Soil water infiltration is the most important hydrological parameter for the evaluation and diagnosis of the soil water balance and soil moisture regime. Those balances and regimes are the main regulating factors of the on site water supply to plants and other soil organisms and of other important processes like runoff, surface and mass erosion, drainage, etc, affecting sedimentation, flooding, soil and water pollution, water supply for different purposes (population, agriculture, industries, hydroelectricity), etc. Therefore the evaluation and measurement of water infiltration rates has become indispensable for the evaluation and modeling of the previously mentioned processes. Infiltration is one of the most difficult hydrological parameters to evaluate or measure accurately. Although the theoretical aspects of the process of soil water infiltration are well known since the middle of the past century, when several methods and models were already proposed for the evaluation of infiltration, still nowadays such evaluation is not frequently enough accurate for the purposes being used. This is partially due to deficiencies in the methodology being used for measuring infiltration, including some newly proposed methods and equipments, and in the use of non appropriate empirical models and approaches. In this contribution we present an analysis and discussion about the main difficulties found in the evaluation and measurement of soil water infiltration rates, and the more commonly committed errors, based on the past experiences of the author in the evaluation of soil water infiltration in many different soils and land conditions, and in their use for deducing soil water balances under variable and changing climates. It is concluded that there are not models or methods universally applicable to any soil and land condition, and that in many cases the results are significantly influenced by the way we use a particular method or instrument, and by the alterations in the soil

  16. Overview of chemical vapor infiltration

    Energy Technology Data Exchange (ETDEWEB)

    Besmann, T.M.; Stinton, D.P.; Lowden, R.A.

    1993-06-01

    Chemical vapor infiltration (CVI) is developing into a commercially important method for the fabrication of continuous filament ceramic composites. Current efforts are focused on the development of an improved understanding of the various processes in CVI and its modeling. New approaches to CVI are being explored, including pressure pulse infiltration and microwave heating. Material development is also proceeding with emphasis on improving the oxidation resistance of the interfacial layer between the fiber and matrix. This paper briefly reviews these subjects, indicating the current state of the science and technology.

  17. Air pollutant penetration through airflow leaks into buildings

    Energy Technology Data Exchange (ETDEWEB)

    Liu, De-Ling [Univ. of California, Berkeley, CA (United States)

    2002-01-01

    The penetration of ambient air pollutants into the indoor environment is of concern owing to several factors: (1) epidemiological studies have shown a strong association between ambient fine particulate pollution and elevated risk of human mortality; (2) people spend most of their time in indoor environments; and (3) most information about air pollutant concentration is only available from ambient routine monitoring networks. A good understanding of ambient air pollutant transport from source to receptor requires knowledge about pollutant penetration across building envelopes. Therefore, it is essential to gain insight into particle penetration in infiltrating air and the factors that affect it in order to assess human exposure more accurately, and to further prevent adverse human health effects from ambient particulate pollution. In this dissertation, the understanding of air pollutant infiltration across leaks in the building envelope was advanced by performing modeling predictions as well as experimental investigations. The modeling analyses quantified the extent of airborne particle and reactive gas (e.g., ozone) penetration through building cracks and wall cavities using engineering analysis that incorporates existing information on building leakage characteristics, knowledge of pollutant transport processes, as well as pollutant-surface interactions. Particle penetration is primarily governed by particle diameter and by the smallest dimension of the building cracks. Particles of 0.1-1 μm are predicted to have the highest penetration efficiency, nearly unity for crack heights of 0.25 mm or higher, assuming a pressure differential of 4 Pa or greater and a flow path length of 3 cm or less. Supermicron and ultrafine particles (less than 0.1 μm) are readily deposited on crack surfaces by means of gravitational settling and Brownian diffusion, respectively. The fraction of ozone penetration through building leaks could vary widely, depending significantly on its

  18. The results of air treatment process modeling at the location of the air curtain in the air suppliers and ventilation shafts

    Directory of Open Access Journals (Sweden)

    Nikolaev Aleksandr

    2017-01-01

    Full Text Available In the existing shaft air heater installations (AHI, that heat the air for air suppliers in cold seasons, a heater channel is used. Some parts of the air from the heater go to the channel, other parts are sucked through a pithead by the general shaft pressure drawdown formed by the main ventilation installation (MVI. When this happens, a mix of two air flows leads to a shaft heat regime violation that can break pressurization of intertubular sealers. The problem of energy saving while airing underground mining enterprises is also very important. The proposed solution of both tasks due to the application of an air curtain is described in the article. In cold seasons the air treatment process should be used and it is offered to place an air curtain in the air suppliers shaft above the place of interface of the calorifer channel to a trunk in order to avoid an infiltration (suction of air through the pithead. It’s recommended to use an air curtain in a ventilation shaft because it reduces external air leaks thereby improving energy efficiency of the MVI work. During the mathematical modeling of ventilation and air preparation process (in SolidWorks Flowsimulation software package it was found out that the use of the air curtain in the air supply shaft can increase the efficiency of the AHI, and reduce the electricity consumption for ventilation in the ventilation shaft.

  19. The rate of adverse events during IV conscious sedation.

    Science.gov (United States)

    Schwamburger, Nathan T; Hancock, Raymond H; Chong, Chol H; Hartup, Grant R; Vandewalle, Kraig S

    2012-01-01

    Conscious sedation has become an integral part of dentistry; it is often used to reduce anxiety or fear in some patients during oral surgery, periodontal surgery, implant placement, and general dentistry procedures. The purpose of this study was to evaluate the frequency of adverse events during IV conscious sedation provided by credentialed general dentists and periodontists in the United States Air Force (USAF). Sedation clinical records (Air Force Form 1417) from calendar year 2009 were requested from all USAF bases. A total of 1,468 records were reviewed and 19 adverse events were noted in 17 patients. IV complication (infiltration) was the most common adverse event. The overall adverse event rate was 1.3 per 100 patients treated. The results of this study show that moderate sedation provided by general dentists and periodontists in the USAF has a low incidence of adverse events, and conscious sedation remains a viable option for providers for the reduction of anxiety in select patients.

  20. Fate of Arsenic during Red River Water Infiltration into Aquifers beneath Hanoi, Vietnam.

    Science.gov (United States)

    Postma, Dieke; Mai, Nguyen Thi Hoa; Lan, Vi Mai; Trang, Pham Thi Kim; Sø, Helle Ugilt; Nhan, Pham Quy; Larsen, Flemming; Viet, Pham Hung; Jakobsen, Rasmus

    2017-01-17

    Recharge of Red River water into arsenic-contaminated aquifers below Hanoi was investigated. The groundwater age at 40 m depth in the aquifer underlying the river was 1.3 ± 0.8 years, determined by tritium-helium dating. This corresponds to a vertical flow rate into the aquifer of 19 m/year. Electrical conductivity and partial pressure of CO 2 (P CO 2 ) indicate that water recharged from the river is present in both the sandy Holocene and gravelly Pleistocene aquifers and is also abstracted by the pumping station. Infiltrating river water becomes anoxic in the uppermost aquifer due to the oxidation of dissolved organic carbon. Further downward, sedimentary carbon oxidation causes the reduction of As-containing Fe-oxides. Because the release of arsenic by reduction of Fe-oxides is controlled by the reaction rate, arsenic entering the solution becomes highly diluted in the high water flux and contributes little to the groundwater arsenic concentration. Instead, the As concentration in the groundwater of up to 1 μM is due to equilibrium-controlled desorption of arsenic, adsorbed to the sediment before river water started to infiltrate due to municipal pumping. Calculations indicate that it will take several decades of river water infiltration to leach arsenic from the Holocene aquifer to below the World Health Organization limit of 10 μg/L.

  1. Fate of Arsenic during Red River Water Infiltration into Aquifers beneath Hanoi, Vietnam

    Science.gov (United States)

    2016-01-01

    Recharge of Red River water into arsenic-contaminated aquifers below Hanoi was investigated. The groundwater age at 40 m depth in the aquifer underlying the river was 1.3 ± 0.8 years, determined by tritium–helium dating. This corresponds to a vertical flow rate into the aquifer of 19 m/year. Electrical conductivity and partial pressure of CO2 (PCO2) indicate that water recharged from the river is present in both the sandy Holocene and gravelly Pleistocene aquifers and is also abstracted by the pumping station. Infiltrating river water becomes anoxic in the uppermost aquifer due to the oxidation of dissolved organic carbon. Further downward, sedimentary carbon oxidation causes the reduction of As-containing Fe-oxides. Because the release of arsenic by reduction of Fe-oxides is controlled by the reaction rate, arsenic entering the solution becomes highly diluted in the high water flux and contributes little to the groundwater arsenic concentration. Instead, the As concentration in the groundwater of up to 1 μM is due to equilibrium-controlled desorption of arsenic, adsorbed to the sediment before river water started to infiltrate due to municipal pumping. Calculations indicate that it will take several decades of river water infiltration to leach arsenic from the Holocene aquifer to below the World Health Organization limit of 10 μg/L. PMID:27958705

  2. On the calculation of air flow rates to ventilate closed-type stations in subway with the double-track tunnel

    Science.gov (United States)

    Kiyanitsa, LA

    2018-03-01

    Metro is not only the most promising kind of public transport but also an important part of infrastructure in a modern city. As a place where large groups of people gather, subway is to ensure the required air exchange at the passenger platforms of the stations. The air flow rate for airing the stations is also determined based on the required temperature, humidity and MAC of gases. The present study estimates the required air flow rate at the passenger platform of the closed-type subway station with the double-track tunnel given the standard air temperature, humidity and gas concentration, as well as based on the condition of the specified air flow feed and air changes per hour. The article proposes the scheme of air recirculation from the double-track tunnel to the station.

  3. Comparison BIPM.RI(I)-K8 of high dose-rate Ir-192 brachytherapy standards for reference air kerma rate of the PTB and the BIPM

    International Nuclear Information System (INIS)

    Kessler, C.; Allisy-Roberts, P.J.; Selbach, H.J.

    2015-01-01

    An indirect comparison of the standards for reference air kerma rate (RAKR) for 192 Ir high dose rate (HDR) brachytherapy sources of the Physikalisch-Technische Bundesanstalt (PTB), Germany, and of the Bureau International des Poids et Mesures (BIPM) was carried out at the PTB in September 2011. The comparison result, based on the calibration coefficients for a transfer standard and expressed as a ratio of the PTB and the BIPM standards for reference air kerma rate, is 1.0003 with a combined standard uncertainty of 0.0099. (authors)

  4. Wound infiltration with local anesthetic after abdominal surgery

    International Nuclear Information System (INIS)

    Shah, Z.; Ahmad, R.; Haider, S.M.

    2003-01-01

    This study was carried out to compare the effect of analgesia with local wound infiltration with 20ml of 0.5% bupivacaine in post operative wounds with the control group having no infiltration. Patients were mobilized much earlier than in the control group while the demand of analgesics was considerably delayed in the study group. No any complications was noticed during local infiltration of wounds after abdominal surgery and is, therefore, applicable in routine surgery. (author)

  5. Light propagation in Liquid-infiltrated Microstructured Optical Fibres”

    DEFF Research Database (Denmark)

    Rasmussen, Per Dalgaard

    2008-01-01

    The work presented in this thesis is focussed on studying the possibilities of tuning and optimizing the performance of infiltrated waveguides in systems where nonlinear optical effects are exploited. Infiltrated systems where either nonlinear temporal or spatial effects come into play have been...... considered. First a general introduction to the basic principles used throughout the work is given. It is then shown how infiltrated waveguides can be used for manipulating dispersive and diffractive properties of light propagartion....

  6. A study on the effects of system pressure on heat and mass transfer rates of an air cooler

    International Nuclear Information System (INIS)

    Jung, Hyung Ho

    2002-01-01

    In the present paper, the effects of inlet pressure on the heat and mass transfer rates of an air cooler are numerically predicted by a local analysis method. The pressures of the moist air vary from 2 to 4 bars. The psychometric properties such as dew point temperature, relative humidity and humidity ratio are employed to treat the condensing water vapor in the moist air when the surface temperatures are dropped below the dew point. The effects of the inlet pressures on the heat transfer rate, the dew point temperature, the rate of condensed water, the outlet temperature of air and cooling water are calculated. The condensation process of water vapor is discussed in detail. The results of present calculations are compared with the test data and shows good agreements

  7. Pollutant removal in subsurface wastewater infiltration systems with ...

    African Journals Online (AJOL)

    Pollutant removal in subsurface wastewater infiltration systems with/without intermittent ... Water SA. Journal Home · ABOUT THIS JOURNAL · Advanced Search ... wastewater infiltration systems (SWISs) with and without intermittent aeration, ...

  8. Eosinophilic Esophagitis: Relevance of Mast Cell Infiltration.

    Science.gov (United States)

    Strasser, Daniel S; Seger, Shanon; Bussmann, Christian; Pierlot, Gabin M; Groenen, Peter M A; Stalder, Anna K; Straumann, Alex

    2018-05-17

    Eosinophilic esophagitis (EoE) is a chronic-inflammatory disease characterized clinically by symptoms of esophageal dysfunction and histopathologically by a prominent eosinophilic inflammation. Despite eosinophils having histologically a pre-dominant position, their role in the immunopathogenesis of the disease is still questionable. Several other inflammatory cells are involved and may play a critical role as well. The purpose of this study was to characterize the mast cell infiltration, and to correlate it with clinical state of EoE. Using immunohistochemistry and quantitative morphometry, we extensively investigated eosinophils and mast cells in esophageal biopsies from patients with active EoE and from patients with EoE in remission, and compared the findings with healthy individuals. In EoE, epithelium and lamina propria were similarly infiltrated with eosinophils. In contrast, mast cells infiltration was limited to the epithelium, displaying a localized immune response. Interestingly, whereas epithelial mast cells and eosinophils were high in active EoE, some patients in remission e.g. normalized epithelial eosinophils, showed remaining high numbers of mast cells. Patient clustering supported 2 groups of patients in clinical remission, differentiating based on presence or absence of epithelial mast cells. Active EoE is characterized - in addition to the well-known tissue eosinophilia by a marked epithelium-restricted mast cell infiltration. Of interest, in a subgroup of patients, mast cell infiltration persisted despite clinical remission. To elucidate the clinical consequence of persistent epithelial mast cells infiltration further studies are required following patients in clinical remission longitudinally. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  9. Nasal congestion in relation to low air exchange rate in schools. Evaluation by acoustic rhinometry.

    Science.gov (United States)

    Wålinder, R; Norbäck, D; Wieslander, G; Smedje, G; Erwall, C

    1997-09-01

    Upper airway symptoms are common, but there is little information available on clinical findings in relation to indoor air pollution. This pilot study was conducted to test whether increased levels of indoor air pollutants in schools may correlate to a swelling of the nasal mucosa. The assumption was made that the degree of swelling could be related to the degree of decongestive effect of xylometazoline, and measured by acoustic rhinometry. The study was performed among 15 subjects in a school with low air exchange rate (0.6 air changes/h) and 12 subjects in a school with high air exchange rate (5.2 air changes/h). Hygienic measurements were performed in both schools. Acoustic rhinometry was performed for each individual under standardized forms. Cross-sectional areas and volumes of the nasal cavity were measured before and after decongestion with xylometazoline hydrochloride. Absolute values of the minimal cross-sectional area were lower in the school with poor ventilation. The decongestive effect of xylometazoline was significantly higher in the school with low air exchange, when correction for the influence of age was made. A diminished decongestive effect was seen with increasing age. The exposure measurements showed that indoor concentrations of volatile organic compounds, bacteria and moulds were higher in the school with low ventilation. In conclusion, raised levels of indoor air pollutants due to inadequate ventilation in schools may affect the upper airways and cause a swelling of the nasal mucosa, and acoustic rhinometry could be a useful objective method to measure human nasal reactions to the indoor environment.

  10. Survival after cystectomy in infiltrating bladder cancer

    International Nuclear Information System (INIS)

    Mandron, E.; Desrez, G.; Chatelain, C.

    1998-01-01

    We reviewed the results of infiltrating bladder cancer treated by radical cystectomy to evaluate cancer treated by radical cystectomy to evaluate survival. Between January 1989 and December 1992, a total of 58 consecutive cystectomies or anterior pelvic exenterations performed on 48 men and 10 women (mean age 63.2 years) in our department were retrospectively evaluated. Four patients were lost to follow-up and the mean follow-up was 72 months. Pathologic staging was as follows: stage pTO,A,1: 13.5%, stage pT2: 17.5%, stage pT3a: 12%, stage pT3b: stage pT4: 21%. The year probability of the overall survival was 60% for pT2-p T3a patients, 15% for pT3b patients, and 9% for pT4 patients, respectively. Overall, 53.5% of patients died of cancer, 7.5% of intercurrent disease, and 39% were alive. The cancer related death rate was 12% for pT2-pT3a patients, and 82% for pT3b-pT4 patients. The 5- year probability of specific survival was 80% for pT2-pT3a patients, 15% for pT3b patients and 9% for pT4 patients, respectively. Infiltrating bladder cancer still has a high mortality rate. Radical cystectomy may be considered to be a curative procedure for stages pT2 and pT3a. Adjuvant chemotherapy and/or radiotherapy seem necessary at stages pT3 and pT4. Preoperative criteria need to be better defined to reduce understanding. (authors)

  11. Water infiltration into exposed fractured rock surfaces

    International Nuclear Information System (INIS)

    Rasmussen, T.C.; Evans, D.D.

    1993-01-01

    Fractured rock media are present at many existing and potential waste disposal sites, yet characterization data and physical relationships are not well developed for such media. This study focused on water infiltration characteristics of an exposed fractured rock as an approach for defining the upper boundary condition for unsaturated-zone water percolation and contaminant transport modeling. Two adjacent watersheds of 0.24 and 1.73 ha with slopes up to 45% were instrumented for measuring rainfall and runoff. Fracture density was measured from readily observable fracture traces on the surface. Three methods were employed to evaluate the rainfall-runoff relationship. The first method used the annual totals and indicated that only 22.5% of rainfall occurred as runoff for the 1990-1991 water year, which demonstrates a high water intake rate by the exposed fracture system. The second method employed total rainfall and runoff for individual storms in conjunction with the commonly used USDA Soil Conservation Service curve number method developed for wide ranges of soils and vegetation. Curve numbers between 75 and 85 were observed for summer and winter storms with dry antecedent runoff conditions, while values exceeded 90 for wet conditions. The third method used a mass-balance approach for four major storms, which indicated that water intake rates ranged from 2.0 to 7.3 mm h -1 , yielding fracture intake velocities ranging from 122 to 293 m h -1 . The three analyses show the complexity of the infiltration process for fractured rock. However, they contribute to a better understanding of the upper boundary condition for predicting contaminant transport through an unsaturated fractured rock medium. 17 refs., 4 figs., 1 tab

  12. Definição da taxa de infiltração para dimensionamento de sistemas de irrigação por aspersão Definition of the infiltration rate for the design of sprinkle irrigation systems

    Directory of Open Access Journals (Sweden)

    Carlos B. M. Calheiros

    2009-12-01

    Full Text Available Objetivou-se, neste trabalho, determinar, dentre as técnicas nele utilizadas, a mais adequada para a definição da taxa de infiltração visando ao dimensionamento de sistemas de irrigação por aspersão. Obtiveram-se os dados de infiltração de água no solo segundo uma malha com espaçamentos variáveis entre pontos de ensaios de infiltração de 1,5; 3; 6; 12; 24; 48 e 96 m, totalizando 97 pontos de ensaio. As discussões relativas aos resultados obtidos pelas técnicas de definição - moda, média harmônica, mediana, média geométrica, média aritmética simples, média quadrática, média cúbica e média biquadrática, foram alicerçadas em um número maior de atributos, tais como: técnicas de análises estatísticas clássicas e geoestatísticas. O modelo de equação que descreve a taxa de infiltração utilizada foi a de Kostiakov. A média aritmética simples, consagrada como a técnica mais utilizada para definição da taxa de infiltração para dimensionamentos, não deve ser utilizada, sendo a mediana e a média geométricas mais recomendadas em cultivos com cana-de-açúcar; contudo, a mediana apresentou um número maior de atributos desejáveis. Na área estudada o valor da taxa de infiltração para dimensionamentos deve ser adotado entre 30 e 44 mm h-1, em se tratando da Md ± s² (.The aim of this research was to determine which technique is the most appropriate for the infiltration rate definition for the design of sprinkler irrigation systems. The water infiltration data was obtained according to a net having variable spaces between infiltration test points of 1.5, 3, 6, 12, 24, 48 and 96 m, summing 97 test points. The discussions of results obtained by means of definition techniques, i.e. mode, harmonic mean, median, geometric mean, and simple arithmetic mean, square mean, cubic mean and bisquare were based on a larger number of attributes, such as techniques for classical statistics and geostatistical analysis. The

  13. Air pollution and heart rate variability: effect modification by chronic lead exposure.

    Science.gov (United States)

    Park, Sung Kyun; O'Neill, Marie S; Vokonas, Pantel S; Sparrow, David; Wright, Robert O; Coull, Brent; Nie, Huiling; Hu, Howard; Schwartz, Joel

    2008-01-01

    Outdoor air pollution and lead exposure can disturb cardiac autonomic function, but the effects of both these exposures together have not been studied. We examined whether higher cumulative lead exposures, as measured by bone lead, modified cross-sectional associations between air pollution and heart rate variability among 384 elderly men from the Normative Aging Study. We used linear regression, controlling for clinical, demographic, and environmental covariates. We found graded, significant reductions in both high-frequency and low-frequency powers of heart rate variability in relation to ozone and sulfate across the quartiles of tibia lead. Interquartile range increases in ozone and sulfate were associated respectively, with 38% decrease (95% confidence interval = -54.6% to -14.9%) and 22% decrease (-40.4% to 1.6%) in high frequency, and 38% decrease (-51.9% to -20.4%) and 12% decrease (-28.6% to 9.3%) in low frequency, in the highest quartile of tibia lead after controlling for potential confounders. We observed similar but weaker effect modification by tibia lead adjusted for education and cumulative traffic (residuals of the regression of tibia lead on education and cumulative traffic). Patella lead modified only the ozone effect on heart rate variability. People with long-term exposure to higher levels of lead may be more sensitive to cardiac autonomic dysfunction on high air pollution days. Efforts to understand how environmental exposures affect the health of an aging population should consider both current levels of pollution and history of lead exposure as susceptibility factors.

  14. Unidirectional infiltration method to produce crown for dental prosthesis application

    International Nuclear Information System (INIS)

    Pontes, F.H.D.; Taguchi, S.P.; Machado, J.P.B.; Santos, C.

    2009-01-01

    Alumina ceramics have been used in dental prosthesis because it is inert, presents higher corrosion and shear resistance when compared to metals, excellent aesthetic, and mechanical resistance. In this work it was produced an infrastructure material for applications in dental crowns, obtained by glass infiltration in alumina preform. Various oxides, among that, rare-earth oxide produced by Xenotime, were melted at 1450 deg C and heat treatment at 700 deg C to obtain the glass (REglass). The alumina was pre-sintered at 1100 deg C cut and machined to predetermine format (unidirectional indirect infiltration) and finally conducted to infiltration test. The alumina was characterized by porosity (Hg-porosity and density) and microstructure (SEM). The glass wettability in alumina was determined as function of temperature, and the contact angle presented a low value (θ<90 deg), showing that glass can be infiltrated spontaneously in alumina. The infiltration test was conducted at glass melting temperature, during 30, 60, 180, 360 minutes. After infiltration, the samples were cut in longitudinal section, ground and polished, and analyzed by XRD (crystalline phases), SEM (microstructure) and EDS (composition).The REglass presents higher infiltration height when compared to current processes (direct infiltration), and homogeneous microstructure, showing that it is a promising method used by prosthetics and dentists. (author)

  15. Unidirectional infiltration method to produce crown for dental prosthesis application

    Energy Technology Data Exchange (ETDEWEB)

    Pontes, F.H.D.; Taguchi, S.P. [Universidade de Sao Paulo (EEL/DEMAR/USP), Lorena, SP (Brazil). Escola de Engenharia; Borges Junior, L.A. [Centro Universitario de Volta Redonda, RJ (Brazil); Machado, J.P.B. [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil); Santos, C. [ProtMat Materiais Avancados, Guaratingueta, SP (Brazil)

    2009-07-01

    Alumina ceramics have been used in dental prosthesis because it is inert, presents higher corrosion and shear resistance when compared to metals, excellent aesthetic, and mechanical resistance. In this work it was produced an infrastructure material for applications in dental crowns, obtained by glass infiltration in alumina preform. Various oxides, among that, rare-earth oxide produced by Xenotime, were melted at 1450 deg C and heat treatment at 700 deg C to obtain the glass (REglass). The alumina was pre-sintered at 1100 deg C cut and machined to predetermine format (unidirectional indirect infiltration) and finally conducted to infiltration test. The alumina was characterized by porosity (Hg-porosity and density) and microstructure (SEM). The glass wettability in alumina was determined as function of temperature, and the contact angle presented a low value (θ<90 deg), showing that glass can be infiltrated spontaneously in alumina. The infiltration test was conducted at glass melting temperature, during 30, 60, 180, 360 minutes. After infiltration, the samples were cut in longitudinal section, ground and polished, and analyzed by XRD (crystalline phases), SEM (microstructure) and EDS (composition).The REglass presents higher infiltration height when compared to current processes (direct infiltration), and homogeneous microstructure, showing that it is a promising method used by prosthetics and dentists. (author)

  16. Anaesthetic efficacy of supplemental lingual infiltration of mandibular molars after inferior alveolar nerve block plus buccal infiltration in patients with irreversible pulpitis.

    Science.gov (United States)

    Dou, L; Luo, J; Yang, D

    2013-07-01

    To investigate the effect of supplemental lingual infiltration (LI) of mandibular molars following an inferior alveolar nerve block (IANB) plus buccal infiltration (BI) in patients with irreversible pulpitis. Eighty adult patients diagnosed with irreversible pulpitis participated in this prospective study. All patients received standard IANB via injection of 4 mL of 2% lidocaine with 1 : 100,000 epinephrine. Ten minutes after the IANB, patients with numbness of the lower lip were randomly divided into two groups. In the BI group, 40 patients received supplemental BI of 0.9 mL of 4% articaine with 1 : 100,000 epinephrine. In the buccal plus lingual infiltration (BLI) group, 40 patients received supplemental BI of 0.9 mL of 4% articaine with 1 : 100,000 epinephrine and, subsequently, LIs with the same anaesthetic solution and dose. Endodontic access cavity preparation began 15 min after the IANB. Pain during treatment was recorded using a Heft-Parker visual analogue scale. Success was defined when pain was 'none' or 'mild' on endodontic access and initial instrumentation. The pain was estimated and statistically analysed by the chi-squared test (α = 0.05). The success rates for the BI and BLI groups were 70% and 62.5%, respectively. No statistical difference was found between the two groups (P = 0.478). Supplemental LIs are not recommended for administration in mandibular molars with irreversible pulpitis, because they do not improve the anaesthetic success after IANB plus BI. © 2012 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  17. Poster - 15: Air kerma rate measurements using a cylindrical free-air ionization chamber on the 05B1-1 beamline at the Canadian Light Source

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Danielle; Siegbahn, Albert; Fallone, Gino; Warkentin, Brad [BCCA - Sindi Ahluwalia Hawkins Centre for the Southern Interior, Kelowna BC, Stockholm University, Sweden, Cross Cancer Institute, Alberta Health Services and University of Alberta, Edmonton AB, Cross Cancer Institute, Alberta Health Services and University of Alberta, Edmonton AB (Sweden)

    2016-08-15

    Purpose: The BioMedical Imaging and Therapy (BMIT) beamlines at the Canadian Light Source offer the opportunity for investigating novel imaging and therapy applications of synchrotron radiation. A necessary component in advancing this research, and in progressing toward clinical applications, is the availability of accurate dosimetry that is traceable to a standards institution. However, dosimetry in this setting is challenging. These beams are typically small, non-uniform, and highly intense. This work describes air kerma rate measurements on a BMIT beamline using a free-air ionization chamber (FAC). Methods: The measurements were taken at the 05B1-1 beamline (∼8 – 100 keV) for several beam qualities with mean energies between 20.0 and 84.0 keV. The Victoreen Model 480 cylindrical FAC, with a specially fabricated 0.52 mm diameter aperture, was used to measure air kerma rates. The required correction factors were determined using a variety of methods: tabulated data, measurements, theoretical calculations and Monte Carlo simulations (EGSnrc user code egs-fac). Results: The experimental air kerma rates measured between 0.270 ± 13.6% and 312 ± 2.7% Gy/min. At lower energies (low filtration), the most impactful correction factors were those for ion recombination and for x-ray attenuation. Conclusions: These measurements marked the first absolute dosimetry performed at the BMIT beamlines. The experimental and Monte Carlo methods developed will allow air kerma rates to be measured under other experimental conditions, provide a benchmark to which other dosimeters will be compared, and provide a reference for imaging and therapy research programs on this beamline.

  18. Prediction of unsaturated flow and water backfill during infiltration in layered soils

    Science.gov (United States)

    Cui, Guotao; Zhu, Jianting

    2018-02-01

    We develop a new analytical infiltration model to determine water flow dynamics around layer interfaces during infiltration process in layered soils. The model mainly involves the analytical solutions to quadratic equations to determine the flux rates around the interfaces. Active water content profile behind the wetting front is developed based on the solution of steady state flow to dynamically update active parameters in sharp wetting front infiltration equations and to predict unsaturated flow in coarse layers before the front reaches an impeding fine layer. The effect of water backfill to saturate the coarse layers after the wetting front encounters the impeding fine layer is analytically expressed based on the active water content profiles. Comparison to the numerical solutions of the Richards equation shows that the new model can well capture water dynamics in relation to the arrangement of soil layers. The steady state active water content profile can be used to predict the saturation state of all layers when the wetting front first passes through these layers during the unsteady infiltration process. Water backfill effect may occur when the unsaturated wetting front encounters a fine layer underlying a coarse layer. Sensitivity analysis shows that saturated hydraulic conductivity is the parameter dictating the occurrence of unsaturated flow and water backfill and can be used to represent the coarseness of soil layers. Water backfill effect occurs in coarse layers between upper and lower fine layers when the lower layer is not significantly coarser than the upper layer.

  19. Observations on infiltration of silicon carbide compacts with an aluminium alloy

    Science.gov (United States)

    Asthana, R.; Rohatgi, P. K.

    1992-01-01

    The melt infiltration of ceramic particulates permits an opportunity to observe such fundamental materials phenomena as nucleation, dynamic wetting and growth in constrained environments. Experimental observations are presented on the infiltration behavior and matrix microstructures that form when porous compacts of platelet-shaped single crystals of alpha- (hexagonal) silicon carbide are infiltrated with a liquid 2014 Al alloy. The infiltration process involved counter gravity infiltration of suitably tamped and preheated compacts of silicon carbide platelets under an external pressure in a special pressure chamber for a set period, then by solidification of the infiltrant metal in the interstices of the bed at atmospheric pressure.

  20. High Performance Infiltrated Backbones for Cathode-Supported SOFC's

    DEFF Research Database (Denmark)

    Gil, Vanesa; Kammer Hansen, Kent

    2014-01-01

    The concept of using highly ionic conducting backbones with subsequent infiltration of electronically conducting particles has widely been used to develop alternative anode-supported SOFC's. In this work, the idea was to develop infiltrated backbones as an alternative design based on cathode......, microstructural characterization and electrochemical testing are discussed. Data on polarization resistance, Rp, are obtained from impedance spectra recorded on quasi-symmetrical cells (YSZ backbones/YSZ/LSM-YSZ (screen printed)). The backbones are infiltrated with LSM and compared to a standard LSM-YSZ screen...

  1. Assessment on inflow and infiltration in sewerage systems of Kuantan, Pahang.

    Science.gov (United States)

    Yap, Hiew Thong; Ngien, Su Kong

    2017-12-01

    Inflow and infiltration are important aspects of sewerage systems that need to be considered during the design stage and constantly monitored once the sewerage system is in operation. The aim of this research is to analyse the relationship of rainfall as well as inflow infiltration with sewage flow patterns through data collected from fieldwork. Three sewer pipelines were selected at the residential areas of Taman Lepar Hilir Saujana, Bandar Putra and Kota Sas for data collection. Sewage flow data were collected in terms of flowrate, velocity and depth of flow using flowmeters with ultrasonic sensors that utilize the continuous Doppler effect in the sewer pipelines, while rainfall intensity data were collected using rain gauges installed at the study locations. Based on the result, the average infiltration rates of Q peak and Q ave for the locations were 17% and 21%, which exceeded the respective values of 5% and 10% stated in Hammer and Hammer. The flowrate of wastewater in the sewer pipelines was found to be directly proportional to rainfall. These findings indicate that the sewer pipelines in the study areas may have been affected by capacity reduction, whereas the sewerage treatment plants receiving the wastewater influent may have been overloaded.

  2. Managed aquifer recharge of treated wastewater: water quality changes resulting from infiltration through the vadose zone.

    Science.gov (United States)

    Bekele, Elise; Toze, Simon; Patterson, Bradley; Higginson, Simon

    2011-11-01

    Secondary treated wastewater was infiltrated through a 9 m-thick calcareous vadose zone during a 39 month managed aquifer recharge (MAR) field trial to determine potential improvements in the recycled water quality. The water quality improvements of the recycled water were based on changes in the chemistry and microbiology of (i) the recycled water prior to infiltration relative to (ii) groundwater immediately down-gradient from the infiltration gallery. Changes in the average concentrations of several constituents in the recycled water were identified with reductions of 30% for phosphorous, 66% for fluoride, 62% for iron and 51% for total organic carbon when the secondary treated wastewater was infiltrated at an applied rate of 17.5 L per minute with a residence time of approximately four days in the vadose zone and less than two days in the aquifer. Reductions were also noted for oxazepam and temazepam among the pharmaceuticals tested and for a range of microbial pathogens, but reductions were harder to quantify as their magnitudes varied over time. Total nitrogen and carbamazepine persisted in groundwater down-gradient from the infiltration galleries. Infiltration does potentially offer a range of water quality improvements over direct injection to the water table without passage through the unsaturated zone; however, additional treatment options for the non-potable water may still need to be considered, depending on the receiving environment or the end use of the recovered water. Crown Copyright © 2011. Published by Elsevier Ltd. All rights reserved.

  3. Sensitivity of MRI in detecting alveolar infiltrates. Experimental studies; Sensitivitaet der MRT fuer alveolaere Infiltrate. Experimentelle Untersuchungen

    Energy Technology Data Exchange (ETDEWEB)

    Biederer, J.; Busse, I.; Grimm, J.; Reuter, M.; Heller, M. [Kiel Univ. (Germany). Klinikum fuer Diagnostische Radiologie; Muhle, C. [Kiel Univ. (Germany). Klinik fuer Nuklearmedizin; Freitag, S. [Kiel Univ. (Germany). Inst. fuer Medizinische Informatik und Statistik

    2002-08-01

    Purpose: An experimental study using porcine lung explants and a dedicated chest phantom to evaluate the signal intensity of artificial alveolar infiltrates with T{sub 1}- and T{sub 2}-weighted MRI sequences. Material and Methods: 10 porcine lung explants were intubated, transferred into the cavity of a MRI-compatible chest phantom and inflated by continuous evacuation of the artificial pleural space. All lungs were examined with MRI at 1.5 T before and after intra-tracheal instillation of either 100 or 200 ml gelatine-stabilised liquid to simulate alveolar infiltrates. MR-examination comprised gradient echo (2D- and 3D-GRE) and fast spin echo sequences (T{sub 2}-TSE and T{sub 2}-HASTE). The signal intensity of lung parenchyma was evaluated at representative cross sections using a standardised scheme. Control studies were acquired with helical CT. Results: The instilled liquid caused patchy confluent alveolar infiltrates resembling the findings in patients with pneumonia or ARDS. CT revealed typical ground-glass opacities. Before the application of the liquid, only T{sub 2}-HASTE and T{sub 2}-TSE displayed lung parenchyma signals with a signal/noise ratio of 3.62 and 1.39, respectively. After application of the liquid, both T{sub 2}-weighted sequences showed clearly visible infiltrates with an increase in signal intensity of approx. 30% at 100 ml (p<0.01) and 60% at 200 ml (p<0.01). With 2D- and 3D-GRE the infiltrates were not visible, although the lung parenchyma signal increase was statistically significant. On 2D-GRE the increase in signal intensity reached 0.74% (p=0.32) after 100 ml and 5.6% (p<0.01) after 200 ml for 3D-GRE: 2.2% [p=0.02] at 100 ml and 4.4% at 200 ml [p<0.001]. The CT controls revealed a significant increase of lung density of 17. H.E. at 100 ml (p=0.02) and 75 H.E. at 200 ml (p<0.01). Conclusions: MRI with T{sub 2}-weighted sequences detects artificial alveolar infiltrates with high signal intensity and may be a highly sensitive tool to

  4. Ceramic composites by chemical vapor infiltration

    International Nuclear Information System (INIS)

    Stinton, D.P.

    1987-01-01

    Composites consisting of silicon carbide matrices reinforced with continuous ceramic fibers are being developed for high-temperature structural applications. Chemical vapor deposition (CVD) techniques are very effective in fabricating composites with high strengths and exceptional fracture toughness. Mechanical properties of infiltrated composites are controlled by the strength of the interfacial bond between the fibers and matrix. This paper describes two CVD techniques and reviews the models being developed to better understand and control the infiltration process

  5. Novel hydroxyapatite nanorods improve anti-caries efficacy of enamel infiltrants.

    Science.gov (United States)

    Andrade Neto, D M; Carvalho, E V; Rodrigues, E A; Feitosa, V P; Sauro, S; Mele, G; Carbone, L; Mazzetto, S E; Rodrigues, L K; Fechine, P B A

    2016-06-01

    Enamel resin infiltrants are biomaterials able to treat enamel caries at early stages. Nevertheless, they cannot prevent further demineralization of mineral-depleted enamel. Therefore, the aim of this work was to synthesize and incorporate specific hydroxyapatite nanoparticles (HAps) into the resin infiltrant to overcome this issue. HAps were prepared using a hydrothermal method (0h, 2h and 5h). The crystallinity, crystallite size and morphology of the nanoparticles were characterized through XRD, FT-IR and TEM. HAps were then incorporated (10wt%) into a light-curing co-monomer resin blend (control) to create different resin-based enamel infiltrants (HAp-0h, HAp-2h and HAp-5h), whose degree of conversion (DC) was assessed by FT-IR. Enamel caries lesions were first artificially created in extracted human molars and infiltrated using the tested resin infiltrants. Specimens were submitted to pH-cycling to simulate recurrent caries. Knoop microhardness of resin-infiltrated underlying and surrounding enamel was analyzed before and after pH challenge. Whilst HAp-0h resulted amorphous, HAp-2h and HAp-5h presented nanorod morphology and higher crystallinity. Resin infiltration doped with HAp-2h and HAp-5h caused higher enamel resistance against demineralization compared to control HAp-free and HAp-0h infiltration. The inclusion of more crystalline HAp nanorods (HAp-2h and HAp-5h) increased significantly (p<0.05) the DC. Incorporation of more crystalline HAp nanorods into enamel resin infiltrants may be a feasible method to improve the overall performance in the prevention of recurrent demineralization (e.g. caries lesion) in resin-infiltrated enamel. Copyright © 2016 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  6. Elemental depth profiles and plasma etching rates of positive-tone electron beam resists after sequential infiltration synthesis of alumina

    Science.gov (United States)

    Ozaki, Yuki; Ito, Shunya; Hiroshiba, Nobuya; Nakamura, Takahiro; Nakagawa, Masaru

    2018-06-01

    By scanning transmission electron microscopy and energy dispersive X-ray spectroscopy (STEM–EDS), we investigated the elemental depth profiles of organic electron beam resist films after the sequential infiltration synthesis (SIS) of inorganic alumina. Although a 40-nm-thick poly(methyl methacrylate) (PMMA) film was entirely hybridized with alumina, an uneven distribution was observed near the interface between the substrate and the resist as well as near the resist surface. The uneven distribution was observed around the center of a 100-nm-thick PMMA film. The thicknesses of the PMMA and CSAR62 resist films decreased almost linearly as functions of plasma etching period. The comparison of etching rate among oxygen reactive ion etching, C3F8 reactive ion beam etching (RIBE), and Ar ion beam milling suggested that the SIS treatment enhanced the etching resistance of the electron beam resists to chemical reactions rather than to ion collisions. We proposed oxygen- and Ar-assisted C3F8 RIBE for the fabrication of silica imprint molds by electron beam lithography.

  7. Investigation plan for infiltration experiment in Olkiluoto

    International Nuclear Information System (INIS)

    Lehtinen, A.; Lindgren, S.; Ikonen, A.

    2008-11-01

    A three-year field experiment to investigate potential changes in pH and redox conditions, and in buffering capacity as well as the hydrogeochemical processes related to groundwater infiltration is designed for implementation in the vicinity of ONKALO. The idea is to monitor the major infiltration flow path from the ground surface into the upper part of ONKALO at about 50 to 100 m depth depending on the observations made during the experiment. The geochemical evolution of the groundwater is strongly affected by infiltration from the surface. In natural conditions in Olkiluoto most of the geochemical reactions occur along the first few tens of metres of the flow path, in an interface between anaerobic and aerobic conditions. The dissolved aggressive agents, CO 2 and O 2 , of the infiltrating water are consumed and the hydrogeochemistry stabilises on neutral and anaerobic conditions due to weathering processes. As a consequence of this evolution, reaction fronts are formed in the flow channels between acid-neutral and aerobic-anaerobic interfaces. The construction of ONKALO may, however, increase the hydraulic gradient and flow into bedrock, which can move these fronts to deeper depths and decrease the buffering capacity of the rock fractures against surficial water infiltration. Detailed integration of hydrogeochemical (including microbiology), geological and hydrogeological studies is essential for a successful experiment. Accurate hydrogeochemical and hydrogeological data that will be collected during this experiment are used in coupled modelling exercises (P/O studies in site reports), which will be carried out to evaluate the movements of the reaction fronts and the buffering capacity of Olkiluoto bedrock against surficial water infiltration. Good quality information is also necessary for calibrating predictive calculations for the safety case estimating future evolution of the site. In addition to the geochemical targets, the experiment can be used in

  8. Method of forming catalyst layer by single step infiltration

    Science.gov (United States)

    Gerdes, Kirk; Lee, Shiwoo; Dowd, Regis

    2018-05-01

    Provided herein is a method for electrocatalyst infiltration of a porous substrate, of particular use for preparation of a cathode for a solid oxide fuel cell. The method generally comprises preparing an electrocatalyst infiltrate solution comprising an electrocatalyst, surfactant, chelating agent, and a solvent; pretreating a porous mixed ionic-electric conductive substrate; and applying the electrocatalyst infiltration solution to the porous mixed ionic-electric conductive substrate.

  9. Simulation of Groundwater Mounding Beneath Hypothetical Stormwater Infiltration Basins

    Science.gov (United States)

    Carleton, Glen B.

    2010-01-01

    Groundwater mounding occurs beneath stormwater management structures designed to infiltrate stormwater runoff. Concentrating recharge in a small area can cause groundwater mounding that affects the basements of nearby homes and other structures. Methods for quantitatively predicting the height and extent of groundwater mounding beneath and near stormwater Finite-difference groundwater-flow simulations of infiltration from hypothetical stormwater infiltration structures (which are typically constructed as basins or dry wells) were done for 10-acre and 1-acre developments. Aquifer and stormwater-runoff characteristics in the model were changed to determine which factors are most likely to have the greatest effect on simulating the maximum height and maximum extent of groundwater mounding. Aquifer characteristics that were changed include soil permeability, aquifer thickness, and specific yield. Stormwater-runoff variables that were changed include magnitude of design storm, percentage of impervious area, infiltration-structure depth (maximum depth of standing water), and infiltration-basin shape. Values used for all variables are representative of typical physical conditions and stormwater management designs in New Jersey but do not include all possible values. Results are considered to be a representative, but not all-inclusive, subset of likely results. Maximum heights of simulated groundwater mounds beneath stormwater infiltration structures are the most sensitive to (show the greatest change with changes to) soil permeability. The maximum height of the groundwater mound is higher when values of soil permeability, aquifer thickness, or specific yield are decreased or when basin depth is increased or the basin shape is square (and values of other variables are held constant). Changing soil permeability, aquifer thickness, specific yield, infiltration-structure depth, or infiltration-structure shape does not change the volume of water infiltrated, it changes the

  10. Polyacrylamide molecular weight and phosphogypsum effects on infiltration and erosion in semi-arid soils

    Science.gov (United States)

    Seal formation at the surface of semi-arid soils during rainstorms reduces soil infiltration rate (IR) and causes runoff and erosion. Surface application of dry anionic polyacrylamide (PAM) with high molecular weight (MW) has been found to be effective in stabilizing soil aggregates, and decreasing ...

  11. Influence of air flow rate on structural and electrical properties of undoped indium oxide thin films

    International Nuclear Information System (INIS)

    Mirzapour, S.; Rozati, S.M.; Takwale, M.G.; Marathe, B.R.; Bhide, V.G.

    1993-01-01

    Using the spray pyrolysis technique thin films of indium oxide were prepared on Corning glass (7059) at a substrate temperature of 425 C at different flow rates. The electrical and structural properties of these films were studied. The Hall measurements at room temperature showed that the films prepared in an air flow rate of 7 litre min -1 have the highest mobility of 47 cm 2 V -1 s -1 and a minimum resistivity of 1.125 x 10 -3 Ω cm. The X-ray diffraction patterns showed that the films have a preferred orientation of [400] which peaks at the air flow rate of 7 litre min -1 . (orig.)

  12. Measuring OutdoorAir Intake Rates Using Electronic Velocity Sensors at Louvers and Downstream of Airflow Straighteners

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William; Sullivan, Douglas; Cohen, Sebastian; Han, Hwataik

    2008-10-01

    Practical and accurate technologies are needed for continuously measuring and controlling outdoor air (OA) intake rates in commercial building heating, ventilating, and air conditioning (HVAC) systems. This project evaluated two new measurement approaches. Laboratory experiments determined that OA flow rates were measurable with errors generally less than 10percent using electronic air velocity probes installed between OA intake louver blades or at the outlet face of louvers. High accuracy was maintained with OA flow rates as low as 15percent of the maximum for the louvers. Thus, with this measurement approach HVAC systems do not need separate OA intakes for minimum OA supply. System calibration parameters are required for each unique combination of louver type and velocity sensor location but calibrations are not necessary for each system installation. The research also determined that the accuracy of measuring OA flow rates with velocity probes located in the duct downstream of the intake louver was not improved by installing honeycomb airflow straighteners upstream of the probes. Errors varied with type of upstream louver, were as high as 100percent, and were often greater than 25percent. In conclusion, use of electronic air velocity probes between the blades of OA intake louvers or at the outlet face of louvers is a highly promising means of accurately measuring rates of OA flow into HVAC systems. The use of electronic velocity probes downstream of airflow straighteners is less promising, at least with the relatively small OA HVAC inlet systems employed in this research.

  13. Reversible fatty infiltration of the liver

    International Nuclear Information System (INIS)

    Bostel, F.; Hauger, W.

    1987-01-01

    Case studies show that acute pancreatitis occurring independently or combined with a preceding abuse of alcohol may be the cause of fatty infiltration of the liver. These fat areas can evolve in a very short time and provoke in the case of focal incidence diagnostic problems of differentiation against abscesses of metastases. Due to this fact and because of the rapid reversibility of the fatty infiltration under therapy, the safest method to clarify the situation consists of short-term CT controls. (orig.) [de

  14. Topical anesthetic versus lidocaine infiltration in arteriovenous fistula cannulation

    Directory of Open Access Journals (Sweden)

    Anisha George

    2014-01-01

    Full Text Available Background: End stage renal disease (ESRD patients on maintenance hemodialysis undergo arterio-venous fistula (AVF cannulation prior to each hemodialysis session for blood access. Prior to cannulation lidocaine infiltration is done, which is often perceived as painful. Eutectic mixture of local anesthetic (EMLA has been found to significantly reduce pain associated with radial artery cannulation compared with lidocaine infiltration. Aims: To evaluate the efficacy of EMLA compared to infiltration of lidocaine in hemodialysis patients for AVF cannulation. Materials and Methods: A single-centre, crossover study of patients with an AVF on regular maintenance hemodialysis was performed in the dialysis unit of a tertiary care teaching hospital. The site of AVF, number of attempts for AVF cannulation and cannula insertion time were recorded. The patients were asked about the acceptability of application of the anesthetic, delay between anesthetic and cannulation and to score the pain on cannulation. Results: Fifty patients were included in the study. With the visual analog scale, pain score on infiltration was 4.8. Pain score on cannulation after topical application was 2.9 and after infiltration, 2.0. The number of attempts for cannulation and the cannula insertion time were similar. Anesthesia was more stressful in the injectable group rather than the topical group (P < 0.001. Delay between anesthetic and cannulation was unacceptable in the topical group (P < 0.001. Patient compliance was better during infiltration compared to topical (P < 0.005. Mean pain score during infiltration of anesthetic was significantly higher than cannulation pain after either anesthetic, although pain on cannulation was higher in the topical group (P < 0.001. Conclusions: EMLA offers a suitable alternative to lidocaine infiltration for patients using AVF for blood access.

  15. Interpretation of ponded infiltration data using numerical experiments

    Czech Academy of Sciences Publication Activity Database

    Dohnal, M.; Vogel, T.; Dušek, J.; Votrubová, J.; Tesař, Miroslav

    2016-01-01

    Roč. 64, č. 3 (2016), s. 289-299 ISSN 0042-790X Institutional support: RVO:67985874 Keywords : ponded infiltration experiment * two-parameter infiltration equation * three-dimensional axisymmetric dualcontinuum model * preferential flow Subject RIV: DA - Hydrology ; Limnology Impact factor: 1.654, year: 2016

  16. Long-term dynamics of death rates of emphysema, asthma, and pneumonia and improving air quality

    Directory of Open Access Journals (Sweden)

    Kravchenko J

    2014-06-01

    Full Text Available Julia Kravchenko,1 Igor Akushevich,2 Amy P Abernethy,3 Sheila Holman,4 William G Ross Jr,5 H Kim Lyerly1,6 1Department of Surgery, 2Center for Population Health and Aging, 3Duke Clinical Research Institute, Duke University Medical Center, Duke University, Durham, 4Division of Air Quality, North Carolina Department of Environment and Natural Resources, Raleigh, 5Nicholas School of the Environment, 6Department of Pathology, Duke University Medical Center, Duke University, Durham, NC, USA Background: The respiratory tract is a major target of exposure to air pollutants, and respiratory diseases are associated with both short- and long-term exposures. We hypothesized that improved air quality in North Carolina was associated with reduced rates of death from respiratory diseases in local populations. Materials and methods: We analyzed the trends of emphysema, asthma, and pneumonia mortality and changes of the levels of ozone, sulfur dioxide (SO2, nitrogen dioxide (NO2, carbon monoxide (CO, and particulate matters (PM2.5 and PM10 using monthly data measurements from air-monitoring stations in North Carolina in 1993–2010. The log-linear model was used to evaluate associations between air-pollutant levels and age-adjusted death rates (per 100,000 of population calculated for 5-year age-groups and for standard 2000 North Carolina population. The studied associations were adjusted by age group-specific smoking prevalence and seasonal fluctuations of disease-specific respiratory deaths. Results: Decline in emphysema deaths was associated with decreasing levels of SO2 and CO in the air, decline in asthma deaths–with lower SO2, CO, and PM10 levels, and decline in pneumonia deaths–with lower levels of SO2. Sensitivity analyses were performed to study potential effects of the change from International Classification of Diseases (ICD-9 to ICD-10 codes, the effects of air pollutants on mortality during summer and winter, the impact of approach when only

  17. Preparation of TiC/Ni3Al Composites by Upward Melt Infiltration

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    TiC/Ni3Al composites have been prepared using upward infiltration method. The densificstion was performed by both Ni3Al melt filling and TiC sintering during the infiltration. The dissolution of TiC in liquid Ni3Al has been evidenced by finding Ni3(Al,Ti)C after fast cooling in the TiC/Ni3Al composites. The dissolution may be responsible for the infiltration and sintering. Compared with downward infiltration, the upward infiltration brought about higher strength and fracture toughness and shorter infiltration time. TiC/20 vol. pct Ni3Al composite processed by upward infiltration had a flexural strength of 1476 Mpa with a statistic Weibull modulus of 20.2 and a fracture toughness of 20.4 Mpa(m). Better mechanical properties may be attributed to melt unidirectional movement in upward infiltration.

  18. Seasonal variations of indoor microbial exposures and their relation to temperature, relative humidity, and air exchange rate.

    Science.gov (United States)

    Frankel, Mika; Bekö, Gabriel; Timm, Michael; Gustavsen, Sine; Hansen, Erik Wind; Madsen, Anne Mette

    2012-12-01

    Indoor microbial exposure has been related to adverse pulmonary health effects. Exposure assessment is not standardized, and various factors may affect the measured exposure. The aim of this study was to investigate the seasonal variation of selected microbial exposures and their associations with temperature, relative humidity, and air exchange rates in Danish homes. Airborne inhalable dust was sampled in five Danish homes throughout the four seasons of 1 year (indoors, n = 127; outdoors, n = 37). Measurements included culturable fungi and bacteria, endotoxin, N-acetyl-beta-d-glucosaminidase, total inflammatory potential, particles (0.75 to 15 μm), temperature, relative humidity, and air exchange rates. Significant seasonal variation was found for all indoor microbial exposures, excluding endotoxin. Indoor fungi peaked in summer (median, 235 CFU/m(3)) and were lowest in winter (median, 26 CFU/m(3)). Indoor bacteria peaked in spring (median, 2,165 CFU/m(3)) and were lowest in summer (median, 240 CFU/m(3)). Concentrations of fungi were predominately higher outdoors than indoors, whereas bacteria, endotoxin, and inhalable dust concentrations were highest indoors. Bacteria and endotoxin correlated with the mass of inhalable dust and number of particles. Temperature and air exchange rates were positively associated with fungi and N-acetyl-beta-d-glucosaminidase and negatively with bacteria and the total inflammatory potential. Although temperature, relative humidity, and air exchange rates were significantly associated with several indoor microbial exposures, they could not fully explain the observed seasonal variations when tested in a mixed statistical model. In conclusion, the season significantly affects indoor microbial exposures, which are influenced by temperature, relative humidity, and air exchange rates.

  19. Tolerance Levels of Roadside Trees to Air Pollutants Based on Relative Growth Rate and Air Pollution Tolerance Index

    Directory of Open Access Journals (Sweden)

    SULISTIJORINI

    2008-09-01

    Full Text Available Motor vehicles release carbon monoxide, nitrogen dioxide, sulphur dioxide, and particulate matters to the air as pollutants. Vegetation can absorb these pollutants through gas exchange processes. The objective of this study was to examine the combination of the relative growth rate (RGR and physiological responses in determining tolerance levels of plant species to air pollutants. Physiological responses were calculated as air pollution tolerance index (APTI. Eight roadside tree species were placed at polluted (Jagorawi highway and unpolluted (Sindangbarang field area. Growth and physiological parameters of the trees were recorded, including plant height, leaf area, total ascorbate, total chlorophyll, leaf-extract pH, and relative water content. Scoring criteria for the combination of RGR and APTI method was given based on means of the two areas based on two-sample t test. Based on the total score of RGR and APTI, Lagerstroemia speciosa was categorized as a tolerant species; and Pterocarpus indicus, Delonix regia, Swietenia macrophylla were categorized as moderately tolerant species. Gmelina arborea, Cinnamomum burmanii, and Mimusops elengi were categorized as intermediate tolerant species. Lagerstroemia speciosa could be potentially used as roadside tree. The combination of RGR and APTI value was better to determinate tolerance level of plant to air pollutant than merely APTI method.

  20. Microstructure and performance of La0.58Sr0.4Co0.2Fe0.8O3−δ cathodes deposited on BaCe0.2Zr0.7Y0.1O3−δ by infiltration and spray pyrolysis

    DEFF Research Database (Denmark)

    Ricote, Sandrine; Bonanos, Nikolaos; Rørvik, Per Martin

    2012-01-01

    . The area specific resistances obtained are 0.61Ωcm2 and 0.89Ωcm2 at 600°C for the spray-pyrolyzed LSCF cell in dry and humidified air, respectively; the corresponding resistances are 0.63Ωcm2 and 0.98Ωcm2 for the 12 times infiltrated LSCF cell. These resistances are the lowest reported for LSCF cathodes...... from a solution, infiltrated into a screen-printed BZCY27 porous backbone (4 and 12 infiltrations), and one prepared by spray pyrolysis onto a polished electrolyte. In all three cases, LSCF is obtained after annealing at 700°C for 2h. Analysis of the electrochemical impedance spectra between 450°C...... and 600°C in air, with varying p(H2O), reveals that the charge transfer contribution is the lowest for the backbone-infiltrated cathode while the oxygen dissociation/adsorption contribution is the lowest for the spray-pyrolyzed cathode. The area specific resistances increase with the water vapor pressure...

  1. Dataset for Probabilistic estimation of residential air exchange rates for population-based exposure modeling

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset provides the city-specific air exchange rate measurements, modeled, literature-based as well as housing characteristics. This dataset is associated with...

  2. Critical effect of pore characteristics on capillary infiltration in mesoporous films.

    Science.gov (United States)

    Ceratti, D R; Faustini, M; Sinturel, C; Vayer, M; Dahirel, V; Jardat, M; Grosso, D

    2015-03-12

    Capillary phenomena governing the mass-transport (capillary filling, condensation/evaporation) has been experimentally investigated in around 20 different silica thin films exhibiting various porosities with pores dimension ranging from 2 to 200 nm. Films have been prepared by sol-gel chemistry combined with soft-templating approaches and controlled dip coating process. Environmental ellipsometric porosimetry combined with electronic microscopy were used to assess the porosity characteristics. Investigation of lateral capillary filling was performed by following the natural infiltration of water and ionic liquids at the edge of a sessile drop in open air or underneath a PDMS cover. The Washburn model was applied to the displacement of the liquid front within the films to deduce the kinetic constants. The role of the different capillary phenomena were discussed with respect to the porosity characteristics (porosity vol%, pore dimensions and constrictions). We show that correlation between capillary filling rate and pore dimensions is not straightforward. Generally, with a minimum of constrictions, faster filling is observed for larger pores. In the case of mesopores (capillary condensation dynamics, taking place at the meniscus inside the porosity, has to be considered to explain the transport mode. This fundamental study is of interest for applications involving liquids at the interface of mesoporous networks such as nanofluidics, purification, separation, water harvesting or heat transfer.

  3. Fabrication of Cf/SiC composite by chemical vapor infiltration

    International Nuclear Information System (INIS)

    Park, Ji Yeon; Kim, Weon Ju

    2003-07-01

    This technical report reviewed the fabrication process of fiber reinforced ceramic composites, characteristics of the chemical vapor infiltration process, and applications for C f /SiC composite to develop a carbon fiber reinforced silicon carbide composite. Infiltration process was performed by the chemical vapor infiltration process using methyltrichlorosilane and hydrogen gas as a source and a diluent, respectively. Infiltration behavior, phase analysis, microstructure observation were carried out. Parameter study results of C f /SiC composite fabricated with some variables such as reaction pressure, reaction temperature, input gas ratio and preform thickness were described

  4. Emission of formaldehyde by particleboard : effect of ventilation rate and loading on air-contamination levels

    Science.gov (United States)

    George E. Myers; Muneo Nagaoka

    1981-01-01

    Dynamic tests for determining the formaldehyde emission behavior of UF-bonded boards involve the measurement of formaldehyde concentration in the air within a vessel which contains a specified board loading L (m2 of board area per m3 of vessel free volume) and is being ventilated at a specified air exchange rate N (hr.-1). Such tests constitute a primary...

  5. Project Work Plan: Sequestration of Strontium-90 Subsurface Contamination in the Hanford 100-N Area by Surface Infiltration of an Apatite Solution

    Energy Technology Data Exchange (ETDEWEB)

    Szecsody, Jim E.

    2006-04-30

    We propose to develop an infiltration strategy that defines the precipitation rate of an apatite-forming solution and Sr-90 sequestration processes under variably saturated (low water content) conditions. We will develop this understanding through small-scale column studies, intermediate-scale two-dimensional (2-D) experiments, and numerical modeling to quantify individual and coupled processes associated with apatite formation and Sr-90 transport during and after infiltration of the Ca-citrate-PO4 solution. Development of capabilities to simulate these coupled biogeochemical processes during both injection and infiltration will be used to determine the most cost-effective means to emplace an in situ apatite barrier with a longevity of 300 years to permanently sequester Sr-90 until it decays. Biogeochemical processes that will be investigated are citrate biodegradation and apatite precipitation rates at varying water contents as a function of water content. Coupled processes that will be investigated include the influence of apatite precipitation (which occupies pore space) on the hydraulic and transport properties of the porous media during infiltration.

  6. Influence of travel speed on spray deposition uniformity from an air-assisted variable-rate sprayer

    Science.gov (United States)

    A newly developed LiDAR-guided air-assisted variable-rate sprayer for nursery and orchard applications was tested at various travel speeds to compare its spray deposition and coverage uniformity with constant-rate applications. Spray samplers, including nylon screens and water-sensitive papers (WSP)...

  7. Physical studies of porphyrin-infiltrated opal crystals

    Energy Technology Data Exchange (ETDEWEB)

    Sabataityte, J. [Semiconductor Physics Institute, Gostauto 11, LT 01108 Vilnius (Lithuania)], E-mail: julija@pfi.lt; Simkiene, I.; Babonas, G.-J.; Reza, A. [Semiconductor Physics Institute, Gostauto 11, LT 01108 Vilnius (Lithuania); Baran, M.; Szymczak, R. [Institute of Physics, PAN, PL 02668, Warsaw (Poland); Vaisnoras, R.; Rasteniene, L. [Vilnius Pedagogical University, LT 08106, Vilnius (Lithuania); Golubev, V.; Kurdyukov, D. [Ioffe Physico-Technical Institute RAS, 194021, St. Petersburg (Russian Federation)

    2007-09-15

    Artificial opals made of silica spheres and infiltrated with aqueous solution of iron porphyrin (FeTPPS) possessing the absorption band in a visible spectral range were studied. The structural, optical and magnetic properties of composite structures were investigated. Bulk samples of opal structure were obtained by sedimentation technique from colloidal solution of SiO{sub 2} spheres of diameter 240 and 245 nm. The structure of the samples was examined by atomic force microscopy. The properties of photonic crystals were demonstrated by optical measurements in transmission and reflection modes. The stop band was observed in the region 510-550 nm. In samples annealed at 900 deg. C the width of the stop band increased to {approx} 70 nm. Aqueous solutions of FeTPPS of concentration {approx} 1.0 mM and various pH-values were used for infiltration. The infiltration has led to a change of photonic characteristics, position of the stop band and dependence on light incidence angle. The absorption bands typical of FeTPPS were observed in the vicinity of the stop band. The photonic properties of infiltrated opal structures were determined to depend on the acidity of aqueous solution, which was used in technological procedure. Magnetic properties of FeTPPS-infiltrated opal samples, which have been studied at 5-300 K in magnetic fields up to 5 T, were discussed. From magnetic measurements it followed that magnetic Fe-Fe interactions have practically vanished in hybrid samples and Fe centers should be treated as isolated ones.

  8. Physical studies of porphyrin-infiltrated opal crystals

    International Nuclear Information System (INIS)

    Sabataityte, J.; Simkiene, I.; Babonas, G.-J.; Reza, A.; Baran, M.; Szymczak, R.; Vaisnoras, R.; Rasteniene, L.; Golubev, V.; Kurdyukov, D.

    2007-01-01

    Artificial opals made of silica spheres and infiltrated with aqueous solution of iron porphyrin (FeTPPS) possessing the absorption band in a visible spectral range were studied. The structural, optical and magnetic properties of composite structures were investigated. Bulk samples of opal structure were obtained by sedimentation technique from colloidal solution of SiO 2 spheres of diameter 240 and 245 nm. The structure of the samples was examined by atomic force microscopy. The properties of photonic crystals were demonstrated by optical measurements in transmission and reflection modes. The stop band was observed in the region 510-550 nm. In samples annealed at 900 deg. C the width of the stop band increased to ∼ 70 nm. Aqueous solutions of FeTPPS of concentration ∼ 1.0 mM and various pH-values were used for infiltration. The infiltration has led to a change of photonic characteristics, position of the stop band and dependence on light incidence angle. The absorption bands typical of FeTPPS were observed in the vicinity of the stop band. The photonic properties of infiltrated opal structures were determined to depend on the acidity of aqueous solution, which was used in technological procedure. Magnetic properties of FeTPPS-infiltrated opal samples, which have been studied at 5-300 K in magnetic fields up to 5 T, were discussed. From magnetic measurements it followed that magnetic Fe-Fe interactions have practically vanished in hybrid samples and Fe centers should be treated as isolated ones

  9. Study of a new hybrid process combining slurry infiltration and Reactive Chemical Vapour Infiltration for the realisation of Ceramic Matrix Composites

    International Nuclear Information System (INIS)

    Ledain, Olivier

    2014-01-01

    Ceramic matrix composites were originally developed for aerospace,military aeronautics or energy applications thanks to their good properties at high temperature. They are generally made by Chemical Vapor Infiltration (CVI). A new short hybrid process combining fiber preform slurry impregnation of ceramic powders with an innovative Reactive CVI (RCVI) route is proposed to reduce the production time. This route is based on the combination of Reactive Chemical Vapour Deposition (RCVD), which is often used to deposit coatings on fibres, with the Chemical Vapor Infiltration (CVI).In RCVD, the absence of one element of the deposited carbide in the initial gas phase involves the consumption/conversion of the solid substrate. In this work, the RCVD growth and the associated consumption were studied with different parameters in the Ti-H-Cl-C chemical system. The study has been completed with the chemical products analysis, combining XRD, XPS and FTIR. Then, the partial conversion of sub-micrometer carbon powders into titanium carbide and the consolidation of green bodies by RCVI from H 2 /TiCl 4 gaseous infiltration were studied. The residual porosity and the final TiC content were measured in the bulk of the infiltrated powders by image analysis from scanning electron microscopy. Depending on temperature, few hundred micrometers-depth infiltrations are obtained.Finally, the results have been transposed to the RCVI into CMC-type pre-forms. Despite a minimal TiC content of 25% in the overall preform, the results shown a bad homogeneity of the infiltration and a poor cohesion of fibres with RCVI consolidated powder of their environment. (author) [fr

  10. Implications of infiltrating immune cells within bone marrow of patients with diffuse large B-cell lymphoma.

    Science.gov (United States)

    Jeong, Juhyeon; Oh, Eun Ji; Yang, Woo Ick; Kim, Soo Jeong; Yoon, Sun Och

    2017-06-01

    The implications of infiltrating immune cells, especially T cells and macrophages, in the bone marrow (BM) microenvironment of patients with diffuse large B-cell lymphoma (DLBCL) have rarely been studied. We aimed to investigate the significance of infiltrating immune cells in the BM microenvironment as a prognostic factor for DLBCL patients. Using the initial pretreatment BM biopsy obtained from 198 DLBCL patients, we semiquantitatively evaluated CD3+ T cells, CD8+ T cells, and CD163+ macrophages that infiltrate into the paratrabecular and interstitial areas of BM by immunohistochemistry and analyzed their clinicopathological and prognostic implications. Levels of infiltrating CD3+ T cells, CD8+ T cells, and CD163+ macrophages were significantly higher in BM with DLBCL involvement (BMI-positive group) than in that without DLBCL involvement (BMI-negative group). Infiltration of CD8+ T cells significantly increased in cases with advanced Ann Arbor stage, elevated lactate dehydrogenase level, extranodal site involvement ≥2 sites, higher Eastern Cooperative Oncology Group performance status, and higher International Prognostic Index (IPI) risk. High levels of CD3+ T cells were significantly associated with age ≤60, and high levels of CD163+ macrophages were associated with advanced Ann Arbor stage and higher IPI risk. High infiltration of CD8+ T cells was significantly related to inferior overall and recurrence-free survival rate, even in the BMI-negative group. High infiltration of CD8+ T cells within the pretreatment BM was related to poor prognosis, and might be a useful prognostic factor of DLBCL patients. Therefore, evaluation of CD8+ T cells is helpful for predicting prognosis in initial pretreatment BM biopsy of DLBCL patients. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. [Effects of mulching management of Phyllostachys heterocycla forests on the characteristics of soil infiltration and biometrics in southwest Zhejiang Province, China].

    Science.gov (United States)

    Wang, Yi Kun; Jin, Ai Wu; Fang, Sheng Zuo

    2017-05-18

    Soil infiltration, soil physical and chemical properties, root length density and soil fauna diversity were studied in Phyllostachys heterocycla forests with different mulching times in southwest Zhejiang Province, China. Significant differences of soil infiltration capability were found among the forests with different mulching times and among soil layers. Soil infiltration capability generally declined in the deeper soil layers. With mulching management, soil infiltration capability increased under the first mulching, and then declined with the increase of mulching times. The Kostiakov model was suitable for simulating soil infiltration process. With the extending of mulching times (4 to 6 years), soil pH and total/non-capillary porosity decreased, while soil bulk density, soil orga-nic matter and total nitrogen contents increased significantly. Soil initial, steady, and average infiltration rates as well as the cumulative infiltration amount correlated closely with the length density of roots with diameter from 0.5 mm to 5.0 mm, showing a decreasing tendency with the decrease in root length density. Soil fauna density was highest in the forest under the first mulching, and was lowest after third mulching. The decreased numbers of large and meso-arthropods, including Symphyla, Chilopoda, Diplopoda, Hymenoptera and pseudoscorpions, and the micro-arthropods, including Oribatida, Mesostigmata, Onychiuridae, Neanuridae, Cyphoderidae, and Entomobryidae, showed negative effects on soil infiltration. In conclusion, long-term mulching changed soil physical and chemical properties, decreased soil infiltration capability, and suppressed the development of soil fauna, which might cause the decline ofP. heterocycla forests.

  12. Genomic signatures characterize leukocyte infiltration in myositis muscles

    Science.gov (United States)

    2012-01-01

    Background Leukocyte infiltration plays an important role in the pathogenesis and progression of myositis, and is highly associated with disease severity. Currently, there is a lack of: efficacious therapies for myositis; understanding of the molecular features important for disease pathogenesis; and potential molecular biomarkers for characterizing inflammatory myopathies to aid in clinical development. Methods In this study, we developed a simple model and predicted that 1) leukocyte-specific transcripts (including both protein-coding transcripts and microRNAs) should be coherently overexpressed in myositis muscle and 2) the level of over-expression of these transcripts should be correlated with leukocyte infiltration. We applied this model to assess immune cell infiltration in myositis by examining mRNA and microRNA (miRNA) expression profiles in muscle biopsies from 31 myositis patients and 5 normal controls. Results Several gene signatures, including a leukocyte index, type 1 interferon (IFN), MHC class I, and immunoglobulin signature, were developed to characterize myositis patients at the molecular level. The leukocyte index, consisting of genes predominantly associated with immune function, displayed strong concordance with pathological assessment of immune cell infiltration. This leukocyte index was subsequently utilized to differentiate transcriptional changes due to leukocyte infiltration from other alterations in myositis muscle. Results from this differentiation revealed biologically relevant differences in the relationship between the type 1 IFN pathway, miR-146a, and leukocyte infiltration within various myositis subtypes. Conclusions Results indicate that a likely interaction between miR-146a expression and the type 1 IFN pathway is confounded by the level of leukocyte infiltration into muscle tissue. Although the role of miR-146a in myositis remains uncertain, our results highlight the potential benefit of deconvoluting the source of

  13. Primordial radionuclides in soil and their contributions to absorbed dose rate in air

    International Nuclear Information System (INIS)

    Moriones, C.R.; Duran, E.B.; Cruz, F.M. de la

    1989-01-01

    The predominant primordial radionuclides in soil which give rise to terrestrial radiation (external irradiation) were analyzed by gamma spectrometry. 40 K has the highest average activity mass concentration, i.e. 212 Bq kg -1 . 238 U and 232 Th concentrations are much lower and are only 14 and 16 Bq kg -1 respectively. Based on conversion factors given in the UNSCEAR Report (1988), the absorbed dose rates in air at one meter above the ground surface per unit activity mass concentration of primordial radionuclides were calculated. The average per caput absorbed dose rate in air received by Filipinos due to terrestrial radiation is 23 nGy h -1 . The relative contribution of 232 Th series to the total absorbed dose rate is highest, followed closely by 40 K. The contribution of 238 U series is only about one-half that of the 232 Th series. Based on the results obtained, the terrestrial component of the average per caput exposure dose rate due to natural radiation sources is 2.64 μR h -1 or roughly 3 μR h -1 . This leads to an annual average effective dose equivalent to 202 μSv. (Author). 5 annexes; 4 figs.; 3 tabs.; 6 refs

  14. Air-water Gas Exchange Rates on a Large Impounded River Measured Using Floating Domes (Poster)

    Science.gov (United States)

    Mass balance models of dissolved gases in rivers typically serve as the basis for whole-system estimates of greenhouse gas emission rates. An important component of these models is the exchange of dissolved gases between air and water. Controls on gas exchange rates (K) have be...

  15. Evaluation of the psychometric properties of the phlebitis and infiltration scales for the assessment of complications of peripheral vascular access devices.

    Science.gov (United States)

    Groll, Dianne; Davies, Barbara; Mac Donald, Joan; Nelson, Susanne; Virani, Tazim

    2010-01-01

    To prevent complications from peripheral vascular access device (PVAD) therapy, the Infusion Nurses Society (INS) developed 2 scales to measure the extent and severity of phlebitis and infiltration in PVADs. This study evaluated the psychometric properties of these scales to validate them with respect to their interrater reliability, concurrent validity, feasibility, and acceptability. A total of 182 patients at 2 sites were enrolled, and 416 observations of PVAD sites were made. Two nurses independently rated each PVAD site for the presence or absence of phlebitis and/or infiltration by using the INS scales. The interrater reliability was calculated, as was the agreement of the observed versus charted incidence of phlebitis and infiltration (concurrent validity) and the ease of use of the scales (feasibility, acceptability). Interrater reliability for both the Phlebitis and Infiltration scales and concurrent validity were found to be statistically significant (P Phlebitis and Infiltration scales have been shown to be easy to use, valid, and reliable scales.

  16. Tunable photoluminescence of porous silicon by liquid crystal infiltration

    International Nuclear Information System (INIS)

    Ma Qinglan; Xiong Rui; Huang Yuanming

    2011-01-01

    The photoluminescence (PL) of porous silicon films has been investigated as a function of the amount of liquid crystal molecules that are infiltrated into the constricted geometry of the porous silicon films. A typical nematic liquid crystal 4-pentyl-4'-cyanobiphenyl was employed in our experiment as the filler to modify the PL of porous silicon. It is found that the originally red PL of porous silicon films can be tuned to blue by simply adjusting the amount of liquid crystal molecules in the microchannels of the porous films. The chromaticity coordinates are calculated for the recorded PL spectra. The mechanism of the tunable PL is discussed. Our results have demonstrated that the luminescent properties of porous silicon films can be efficiently tuned by liquid crystal infiltration. - Highlights: → Liquid crystal infiltration can tune the photoluminescence of porous silicon. → Red emission of porous silicon can be switched to blue by the infiltration. → Chromaticity coordinates are calculated for the tuned emissions. → White emission is realized for porous silicon by liquid crystal infiltration.

  17. Evaluation of IgG4+ Plasma Cell Infiltration in Patients with Systemic Plasmacytosis and Other Plasma Cell-infiltrating Skin Diseases

    Directory of Open Access Journals (Sweden)

    Shintaro Takeoka

    2018-02-01

    Full Text Available Systemic plasmacytosis is a rare skin disorder characterized by marked infiltration of plasma cells in the dermis. IgG4-related disease is pathologically characterized by lymphoplasmacytic infiltration rich in IgG4+ plasma cells, storiform fibrosis, and obliterative phlebitis, accompanied by elevated levels of serum IgG4. Reports of cases of systemic plasmacytosis with abundant infiltration of IgG4+ plasma cells has led to discussion about the relationship between systemic plasmacytosis and IgG4-related disease. This study examined IgG4+/IgG+ plasma cell ratios in 4 patients with systemic plasmacytosis and 12 patients with other skin diseases that show marked infiltration of plasma cells. Furthermore, we examined whether these cases met one of the pathological diagnostic criteria for IgG4-related disease (i.e. IgG4+/IgG plasma cells ratio of over 40%. Only one out of 4 patients with systemic plasmacytosis met the criterion. These results suggest that systemic plasmacytosis and IgG4-related disease are distinct diseases.

  18. A METHOD AND AN ELECTRODE PRODUCED BY INFILTRATION

    DEFF Research Database (Denmark)

    2014-01-01

    The present invention relates to electrodes having Gd and Pr -doped cerium oxide (CGPO)backbones infiltrated with Sr -doped LaCoO3 (LSC) and a method to manufacture them. Pr ions have been introduced into a prefabricated CGO backbone by infiltrating Pr nitrate solution followed by high temperatur...

  19. Image-guided lumbar facet joint infiltration in nonradicular low back pain

    International Nuclear Information System (INIS)

    Chaturvedi, Arti; Chaturvedi, Sunil; Sivasankar, Rajiv

    2009-01-01

    To assess the efficacy of facet joint infiltrations for pain relief in 44 selected patients with chronic nonradicular low back pain (LBP). Forty-four patients with chronic LBP of more than 3 months' duration were selected for facet joint infiltration. The majority (n = 24) had facetal pain with no evidence of significant facetal arthropathy on imaging. Fifteen patients had radiological evidence of facetal arthropathy, one had a facet joint synovial cyst, three were post–lumbar surgery patients, and two patients had spondylolysis. Facet joint injections were carried out under fluoroscopic guidance in 39 patients and under CT guidance in 5 cases. Pain relief was assessed using the visual analog scale at 1 h post-procedure and, thereafter, at 1, 4, 12, and 24 weeks. A total of 141 facet joints were infiltrated in 44 patients over a 2-year period. There was significant pain relief in 81.8% patients 1 h after the procedure, in 86.3% after 1 week, in 93.3% after 4 weeks, in 85.7% after 12 weeks, and in 62.5% after 24 weeks. No major complications were encountered. Facet nerve block was found to be a simple, minimally invasive, and safe procedure. With meticulous patient selection, we achieved long-term success rates of over 60%. We conclude that this method represents an important alternative treatment for nonradicular back pain

  20. Tumor-Infiltrating Immune Cells Promoting Tumor Invasion and Metastasis: Existing Theories

    Directory of Open Access Journals (Sweden)

    Yan-gao Man, Alexander Stojadinovic, Jeffrey Mason, Itzhak Avital, Anton Bilchik, Bjoern Bruecher, Mladjan Protic, Aviram Nissan, Mina Izadjoo, Xichen Zhang, Anahid Jewett

    2013-01-01

    Full Text Available It is a commonly held belief that infiltration of immune cells into tumor tissues and direct physical contact between tumor cells and infiltrated immune cells is associated with physical destructions of the tumor cells, reduction of the tumor burden, and improved clinical prognosis. An increasing number of studies, however, have suggested that aberrant infiltration of immune cells into tumor or normal tissues may promote tumor progression, invasion, and metastasis. Neither the primary reason for these contradictory observations, nor the mechanism for the reported diverse impact of tumor-infiltrating immune cells has been elucidated, making it difficult to judge the clinical implications of infiltration of immune cells within tumor tissues. This mini-review presents several existing hypotheses and models that favor the promoting impact of tumor-infiltrating immune cells on tumor invasion and metastasis, and also analyzes their strength and weakness.

  1. The Incidence of Malignant Infiltration in the Biopsy Tract of Osteosarcoma

    Directory of Open Access Journals (Sweden)

    R Mohana

    2007-11-01

    Full Text Available Biopsy is a crucial step in the management of musculoskeletal sarcoma. The surgical approach to the biopsy site is important, as the tract must be removed en bloc with the tumour during limb sparing surgery so as to reduce the risk of local recurrence. The biopsy tracts of 26 osteosarcoma patients were evaluated histologically for tumour infiltration. Horizontal sections of 1 mm thickness with 2 cm radius from were evaluated from each excised biopsy tract. Five out of 26 cases (19.2% showed positive tumour infiltration. One case (3.85% had tumour infiltration in the pseudocapsule, two cases (7.69% had tumour infiltration into the muscle and two other cases (7.69% had tumour infiltration into the subcutaneous tissue. None had skin infiltration. We conclude that resection of the entire biopsy tract is indeed mandatory for surgical treatment of osteosarcoma.

  2. On-site infiltration of a copper roof runoff: role of clinoptilolite as an artificial barrier material.

    Science.gov (United States)

    Athanasiadis, Konstantinos; Helmreich, Brigitte; Horn, Harald

    2007-08-01

    On-site infiltration may be considered as a promising way of managing rainwater runoffs in urban areas, provided the hydrological and ecological conditions allow infiltration, and provided there is adequate treatment of the contaminants to avoid a risk of soil and groundwater pollution. The aim of this study was to evaluate the feasibility of the application of a new technical infiltration system equipped with clinoptilolite as an artificial barrier material for the treatment of the copper roof runoff of the Academy of Fine Arts in Munich, Germany. During the 2-yr sampling period, 30 rain events were examined. The cover material of the roof and the drainage system was responsible for the high copper concentrations in the roof runoff. The rain height and the rain intensity were of great significance regarding the establishment of the copper runoff rate. The technical infiltration system applied was able to reduce the copper from the roof runoff by a factor up to 96%. The mean measured copper concentration in percolation water was lower than the critical value of 50 microg/l set by the German Federal Soil Protection Act and Ordinance, indicating no risk for soil and groundwater contamination.

  3. Reactive melt infiltration of copper in Al–Cr preforms produced through combustion synthesis

    International Nuclear Information System (INIS)

    Naplocha, Krzysztof; Granat, Kazimierz; Kaczmar, Jacek

    2014-01-01

    Highlights: • Determination of microstructure and phase transformation during combustion synthesis and reactive infiltration. • Squeeze casting of Cu inducing reactive infiltration of Al–Cr intermetallic porous preform. • Fabrication of unique composite material resisted to high temperature oxidation. - Abstract: Combustion synthesis of Al–Cr preforms used for infiltration and reinforcing of composite materials was developed. Compacts of powdered Al and Cr with stoichiometric ratio Al/Cr equal to 2/1 were synthesized in a microwave reactor furnished with a pyrometer for controlling phase transformations. Due to low enthalpy of the reaction, green compacts were preheated and ignition occurred together with partial melting of Al at the interface with Cr particles. The synthesis proceeded by peritectic transformations L + Al 7 Cr → L + Al 11 Cr 2 → L + Al 4 Cr, reaching maximum temperature of ca. 1000 °C. Porous structures including residual unprocessed Cr particles were soaked to homogenize them and to transform the phases into the stable intermetallic compound Al 9 Cr 4 . Reactive infiltration of the preforms with molten Cu proceeds along with interfacial diffusion of Al that, released from a preform, infiltrates into the matrix changing its composition to Cu 9 Al 4 (Cr). At the same time, the preform is decomposed and converted into a mixture of globular precipitates of Cr 52 Al 35 Cu 13 embedded in the Cu 47 Al 41 Cr 12 phase. The produced composite materials exhibit significant hardness and oxidation resistance at elevated temperatures. The protective layer is composed of oxides Al 2 O 3 and (AlCu) 2 O 3 created at parabolic constant oxidation rate (k p ) equal to 1.9 × 10 −6 g 2 m −4 s −1

  4. Squamous cell carcinoma following radiation therapy for the infiltrative thymoma

    International Nuclear Information System (INIS)

    Ozawa, Shinji; Kitao, Takeshi

    1992-01-01

    This report represents one case of infiltrative thymoma followed by squamous cell carcinoma of the lungs. A 69-year-old man suffered from infiltrative thymoma which reduced by the radiation therapy. Seven years later its replase and the onset of squamous cell carcinoma were found simultaneously. Infiltrative thymoma metastasized not only to the mediastinum but also to the liver and bronchus. Squamous cell carcinoma developed in the right upper lobe. In spite of chemotherapy against them, the patient died. There are many cases in which infiltrative thymoma is accompanied by squamous cell carcinoma of the lung simultaneously; however, secondary onset of squamous cell carcinoma after the radiation therapy of infiltrative thymoma is rare. Secondary carcinogenesis of this case was considered to be closely related with immunological abnormalities caused by thymoma, effects of radiation, smoking and so on. (author)

  5. Tunable Beam Diffraction in Infiltrated Microstructured Fibers

    DEFF Research Database (Denmark)

    Rosberg, Christian Romer; Bennet, Francis H.; Neshev, Dragomir N.

    We experimentally study beam propagation in two dimensional photonic lattices in microstructured optical fibers infiltrated with high index liquids. We demonstrate strongly tunable beam diffraction by dynamically varying the coupling between individual lattice sites.......We experimentally study beam propagation in two dimensional photonic lattices in microstructured optical fibers infiltrated with high index liquids. We demonstrate strongly tunable beam diffraction by dynamically varying the coupling between individual lattice sites....

  6. [Is therapy with local infiltrations feasible in primary care consultations?].

    Science.gov (United States)

    Magaña Loarte, J E; Pérez Franco, J; Sánchez Sánchez, G

    1999-01-01

    To study the feasibility of local infiltration in primary care consultations. Before-and-after intervention study. Two clinics at an urban health centre. Patients diagnosed with pathology of tender areas and treated with corticosteroid infiltration between May 1997 and May 1998. Corticoid infiltration plus local anaesthetic. Weekly check-up. Analysis of the variables: sex, age, diagnosis, time elapsed between indication and start of treatment, subjective assessment of pain before and after treatment (VRS scale), number of infiltrations per patient, side-effects. Evaluation of overall and individual effectiveness. 41 patients were infiltrated. Average age was 58. Most common pathologies were: rotary joint tendinitis (48.7%), anserine bursitis (24.4%), plantar fasciitis (7.3%). Average number of infiltrations per pathology: 1.3. Mean waiting time: 3.5 days. Comparison of pain by means of VRS (range 0-5) before and after treatment used the Wilcoxon test, with a statistically significant difference and p < 0.001 (z = -5.5109). For 35 patients (85.4%), pain was solved very well (values 0 and 1 on the VRS). For 3 patients (7.3%), improvement was moderate; and for 3 (7.3%) there was no improvement. 1. Treatment with local infiltration of corticosteroids is effective in dealing with pain, and is an alternative to treatment with NSAIDs. 2. It is feasible in primary care, and there are many advantages if the general practitioner employs this therapeutic technique.

  7. Does surgery for deep infiltrating bowel endometriosis improve fertility? A systematic review.

    Science.gov (United States)

    Iversen, Maja L; Seyer-Hansen, Mikkel; Forman, Axel

    2017-06-01

    Reduced fertility is a major concern in women with endometriosis. The influence of surgery of deep infiltrating endometriosis (DIE) affecting the bowel wall on fertility is controversial and the literature on this field is heterogeneous. In this review we addressed whether surgery for bowel DIE improves the spontaneous pregnancy rate, and the results of in vitro fertilization (IVF), and the potential risk of such surgery. We conducted a literature search including the terms "deep", "deep infiltrating", "bowel", rectovaginal", "endometriosis", "fertility", "infertility" and "IVF" in PubMed. No randomized controlled studies were found. Other publications of relevance included four retrospective and three prospective observational studies. Moreover, one retrospective study compared results of IVF treatment with or without previous surgery for bowel DIE. All studies reported detailed data on surgical complications. The poor data quality precluded firm conclusions. The results indicate, however, the possibility that surgery for bowel DIE may improve the spontaneous pregnancy rate, and positive effects on IVF outcome cannot be excluded. Such surgery will be associated with risk of major complications. The lack of proper data precludes conclusions on the potential role for bowel DIE surgery to improve the spontaneous pregnancy rate and results of IVF treatment. Positive effects cannot be excluded, but the definite risk of major complications must be taken into account. © 2017 Nordic Federation of Societies of Obstetrics and Gynecology.

  8. Studies on external gamma dose rates in air around Hassan city, Karnataka

    International Nuclear Information System (INIS)

    Shashikumar, T.S.; Gowda, Shivalinge; Chandrashekar; Shivakumar, B.C.

    2017-01-01

    Gamma-ray dose rates in air have been measured in the environment of Hassan City. The measurements were done from 15 locations in and around Hassan city at 1m above from the ground surface using a light weight portable radiation survey meter (Scintillometer) which is suited for radiometric, and environmental surveys. The meter reading fluctuates around a mean value and is proportional to the count rate detected by the unit. This is because of the random nature of radioactivity. The detailed results of the study will be presented. (author)

  9. Estimation of Stormwater Interception Rate for various LID Facilities

    Science.gov (United States)

    Kim, S.; Lee, O.; Choi, J.

    2017-12-01

    In this study, the stormwater interception rate is proposed to apply in the design of LID facilities. For this purpose, EPA-SWMM is built with some areas of Noksan National Industrial Complex where long-term observed stormwater data were monitored and stormwater interception rates for various design capacities of various LID facilities are estimated. While the sensitivity of stormwater interception rate according to design specifications of bio-retention and infiltration trench facilities is not large, the sensitivity of stormwater interception rate according to local rainfall characteristics is relatively big. As a result of comparing the present rainfall interception rate estimation method which is officially operated in Korea with the one proposed in this study, it will be presented that the present method is highly likely to overestimate the performance of the bio-retention and infiltration trench facilities. Finally, a new stormwater interception rate formulas for the bio-retention and infiltration trench LID facilities will be proposed. Acknowledgement This research was supported by a grant (2016000200002) from Public Welfare Technology Development Program funded by Ministry of Environment of Korean government.

  10. On the Properties and Long-Term Stability of Infiltrated Lanthanum Cobalt Nickelates (LCN) in Solid Oxide Fuel Cell Cathodes

    DEFF Research Database (Denmark)

    Kiebach, Wolff-Ragnar; Zielke, Philipp; Veltzé, Sune

    2017-01-01

    Infiltration as a fabrication method for solid oxide fuel cells (SOFC) electrodes is offering significant improvements in cell performance at reduced materials and fabrication costs, especially when combined with co-sintering. However, important questions regarding the long-term performance...... and microstructural stability remain unanswered. Here, we present the results of a three-year project, where large footprint anode-supported SOFCs with a co-sintered cathode backbone and infiltrated La0.95Co0.4Ni0.6O3 (LCN) cathodes were developed and thoroughly characterized. The initial long-term performance...... in the electrode properties using SEM, BET area, and in-plane conductivity measurements. Finally, the mechanical properties of co-sintered cathode backbone cells were determined in four-point bending tests carried out both at room temperature and at 800°C in air. Based on these results, degradation mechanisms were...

  11. Shallow water table effects on water, sediment, and pesticide transport in vegetative filter strips - Part 1: nonuniform infiltration and soil water redistribution

    Science.gov (United States)

    Muñoz-Carpena, Rafael; Lauvernet, Claire; Carluer, Nadia

    2018-01-01

    Vegetation buffers like vegetative filter strips (VFSs) are often used to protect water bodies from surface runoff pollution from disturbed areas. Their typical placement in floodplains often results in the presence of a seasonal shallow water table (WT) that can decrease soil infiltration and increase surface pollutant transport during a rainfall-runoff event. Simple and robust components of hydrological models are needed to analyze the impacts of WT in the landscape. To simulate VFS infiltration under realistic rainfall conditions with WT, we propose a generic infiltration solution (Shallow Water table INfiltration algorithm: SWINGO) based on a combination of approaches by Salvucci and Entekhabi (1995) and Chu (1997) with new integral formulae to calculate singular times (time of ponding, shift time, and time to soil profile saturation). The algorithm was tested successfully on five distinct soils, both against Richards's numerical solution and experimental data in terms of infiltration and soil moisture redistribution predictions, and applied to study the combined effects of varying WT depth, soil type, and rainfall intensity and duration. The results show the robustness of the algorithm and its ability to handle various soil hydraulic functions and initial nonponding conditions under unsteady rainfall. The effect of a WT on infiltration under ponded conditions was found to be effectively decoupled from surface infiltration and excess runoff processes for depths larger than 1.2 to 2 m, being shallower for fine soils and shorter events. For nonponded initial conditions, the influence of WT depth also varies with rainfall intensity. Also, we observed that soils with a marked air entry (bubbling pressure) exhibit a distinct behavior with WT near the surface. The good performance, robustness, and flexibility of SWINGO supports its broader use to study WT effects on surface runoff, infiltration, flooding, transport, ecological, and land use processes. SWINGO is

  12. Fabrication and optical characterization of gold-infiltrated silica opals

    International Nuclear Information System (INIS)

    Li Wenjiang; Sun Gang; Tang Fangqiong; Tam, W.Y.; Li Jensen; Chan, C T; Sheng Ping

    2005-01-01

    We report the fabrication of metal-infiltrated silica opals for optical studies. Highly mono-dispersed silica microspheres are fabricated and assembled by a force packing method to form opals with large domain sizes. The opals are then infiltrated with gold by an electroplating technique. The optical properties of the infiltrated opals in the visible range are studied and model calculations based on a multiple-scattering formalism are used to interpret the experimental results. The calculated position of the directional gap of the silica opal agrees very well with experimental observation. We found that the optical properties of the infiltrated sample can be explained using a model system in which the voids in the silica opal are partially filled with Au and the surface of the slab is covered with a thin layer of Au

  13. Diffuse infiltrative cardiac tuberculosis

    International Nuclear Information System (INIS)

    Gulati, Gurpreet S; Kothari, Shyam S

    2011-01-01

    We present the cardiac magnetic resonance images of an unusual form of cardiac tuberculosis. Nodular masses in a sheet-like distribution were seen to infiltrate the outer myocardium and pericardium along most of the cardiac chambers. The lesions showed significant resolution on antitubercular therapy

  14. Determination of air kerma standard of high dose rate 192Ir brachytherapy source

    International Nuclear Information System (INIS)

    Pires, E.J.; Alves, C.F.E.; Leite, S.P.; Magalhaes, L.A.G.; David, M.G.; Almeida, C.E. de

    2015-01-01

    This paper presents the methodology developed by the Laboratorio de Ciencias Radiologicas and presently in use for determining of the air kerma standard of 192 Ir high dose rate sources to calibrate well-type chambers. Uncertainty analysis involving the measurements procedure are presented. (author)

  15. Ecobuild measurement report of the infiltration measurements of the Ecobuild dwellings and the ICT dwelling; Ecobuild meetverslag infiltratiemetingen van de Ecobuild woningen en de ICT woning

    Energy Technology Data Exchange (ETDEWEB)

    Schuitema, R.; Bakker, E.J. [ECN Zonne-energie, Petten (Netherlands)

    2002-04-01

    By means of blower door measurements the airtightness of so-called Ecobuild dwellings (A, B and C) and the ICT-dwelling (D) has been determined. The airtightness is of importance with regard to calculations on heat losses and the heat balance. Data on air infiltration are important for other similar projects. [Dutch] Met blowerdeur metingen is door J.E. StorkAir de lekdichtheid van de Ecobuild woningen (woning A, B en C) en de ICT woning (woning D) bepaald.

  16. Effects of air pollutants on the carbon dioxide (CO2) emission rate of human subjects

    DEFF Research Database (Denmark)

    Bako-Biro, Zsolt; Wargocki, Pawel; Wyon, David

    2004-01-01

    Several laboratory studies have shown the negative effects of emissions from typical indoor pollution sources on perceived air quality, SBS symptoms and the performance of office work. The subjects performed typical office tasks at their own pace while they were exposed for several hours to diffe...... to different air quality conditions. A re-analysis of the CO2 measurements obtained in two independent studies showed that human CO2 emission rates were affected by air quality (P......Several laboratory studies have shown the negative effects of emissions from typical indoor pollution sources on perceived air quality, SBS symptoms and the performance of office work. The subjects performed typical office tasks at their own pace while they were exposed for several hours...

  17. Dependence of Rn adsorption rate and effective half-life time on diffusion barrier type and moving air environment

    International Nuclear Information System (INIS)

    Arafa, Wafaa; Badran, Heba

    2005-01-01

    The variation of the adsorbed radon rate during the exposure time using charcoal canister was studied applying moving air environment inside the radon chamber and compared to the static air measurements. The air movement increases the accumulation time leading to more accurate results. Different types of membrane have been tested as diffusion barrier for activated charcoal canisters. The Makrofol and aluminized polycarbonate improve the adsorption/desorption rate more than the polyehylene membrane. The measured effective half-life time showed a remarkable correlation with the previously measured permeability constant for corresponding membranes. Different types of commercially available charcoal were investigated to develop a local version of charcoal canister for radon measurements. Applying static and moving air environments, the break point and radon collection efficiency were determined at different temperatures. Both of the temperature and air movement accelerate the appearance of the break point. Th efficiency of the locally developed charcoal is 87% and 84.5% of that Calgon PCB charcoal used by EPA. (author)

  18. Kerma rate evaluation in the air in a room interventional cardiology

    International Nuclear Information System (INIS)

    Real, Jessica V.; Luz, Renata M. da; Fröhlich, Bruna D.; Silva, Ana Maria Marques da

    2014-01-01

    In recent years, the number of interventional cardiology procedures is increasing. However, due to the long time of fluoroscopy in these procedures, care teams can receive high doses of radiation. The radiation scattered by the patient is not uniform, and their assessment is of utmost importance. This study aimed to estimate and map the kerma rate in the air at the time of the gonads, in an interventional cardiology room, seeking to optimize the dose absorbed by individuals occupationally exposed to ionizing radiation. For data collection, the room was divided into quadrants of 1m 2 , totaling 40 collection points. The simulator was positioned so that its entry surface was located in the interventional reference point. Were chosen the conditions that simulate angiography and angioplasty procedures performed in the service. The data were obtained for height of 1 meter, gonad region. The results obtained for kerma rates in air, in quadrants, show that higher measured values was in the vicinity of the X-ray tube. Has been found that the medical staff are more exposed, because of its location during the procedure, around the table. The law of the inverse square distance of the farthest points of the X-ray tube were verified

  19. Infiltrative lipoma compressing the spinal cord in 2 large-breed dogs.

    Science.gov (United States)

    Hobert, Marc K; Brauer, Christina; Dziallas, Peter; Gerhauser, Ingo; Algermissen, Dorothee; Tipold, Andrea; Stein, Veronika M

    2013-01-01

    Two cases of infiltrative lipomas compressing the spinal cord and causing nonambulatory paraparesis in 2 large-breed dogs are reported. Magnetic resonance imaging (MRI) revealed severe extradural spinal cord compression by inhomogenous masses that infiltrated the adjacent tissues and the muscles of the spine in both dogs. The presumptive clinical diagnoses were infiltrative lipomas, which were confirmed by histopathology. In rare cases infiltrative lipomas are able to compress the spinal cord by the agressive growth of invasive adipocytes causing neurological deficits.

  20. Non-uniform overland flow-infiltration model for roadside swales

    Science.gov (United States)

    García-Serrana, María; Gulliver, John S.; Nieber, John L.

    2017-09-01

    There is a need to quantify the hydrologic performance of vegetated roadside swales (drainage ditches) as stormwater control measures (SCMs). To quantify their infiltration performance in both the side slope and the channel of the swale, a model has been developed for coupling a Green-Ampt-Mein-Larson (GAML) infiltration submodel with kinematic wave submodels for both overland flow down the side slope and open channel flow for flow in the ditch. The coupled GAML submodel and overland flow submodel has been validated using data collected in twelve simulated runoff tests in three different highways located in the Minneapolis-St. Paul metropolitan area, MN. The percentage of the total water infiltrated into the side slope is considerably greater than into the channel. Thus, the side slope of a roadside swale is the main component contributing to the loss of runoff by infiltration and the channel primarily conveys the water that runs off the side slope, for the typical design found in highways. Finally, as demonstrated in field observations and the model, the fraction of the runoff/rainfall infiltrated (Vi∗) into the roadside swale appears to increase with a dimensionless saturated hydraulic conductivity (Ks∗), which is a function of the saturated hydraulic conductivity, rainfall intensity, and dimensions of the swale and contributing road surface. For design purposes, the relationship between Vi∗ and Ks∗ can provide a rough estimate of the fraction of runoff/rainfall infiltrated with the few essential parameters that appear to dominate the results.

  1. Bilateral pulmonary infiltrates in association with disseminated actinomycosis.

    Science.gov (United States)

    Dontfraid, F; Ramphal, R

    1994-07-01

    The most common infectious cause of bilateral upper-lobe pulmonary disease is tuberculosis. However, we recently encountered a patient with bilateral apical infiltrates and multiple soft-tissue abscesses caused by Actinomyces odontolyticus. Other findings included fever, weight loss, and leukocytosis, and the patient's only known source of immunosuppression was a long history of alcoholism. There was no history of diabetes, steroid use, or other chronic underlying disease. The diagnosis was made by culture of drainage fluid from one abscess. Therapy with intravenous penicillin G led to rapid clinical improvement and reduction in the infiltrates. To our knowledge, the presentation of pulmonary infection, with bilateral apical infiltrates due to A. odontolyticus has not been previously reported in the medical literature.

  2. Temporal nonlinear beam dynamics in infiltrated photonic crystal fibers

    DEFF Research Database (Denmark)

    Bennet, Francis; Rosberg, Christian Romer; Neshev, Dragomir N.

    Liquid-infiltrated photonic crystal fibers (PCFs) offer a new way of studying light propagation in periodic and discrete systems. A wide range of available fiber structures combined with the ease of infiltration opens up a range of novel experimental opportunities for optical detection and bio...... the evolution of the fiber output beam in the few micro or milliseconds after the beam is turned on. The characterization of the temporal behavior of the thermal nonlinear response provides important information about the nonlocality associated with heat diffusion inside the fiber, thus enabling studies of long...... and technological potential of liquid-infiltrated PCFs it is important to understand the temporal dynamics of nonlinear beam propagation in such structures. In this work we consider thermally induced spatial nonlinear effects in infiltrated photonic crystal fibers. We experimentally study the temporal dynamics...

  3. Modeling rainfall infiltration on hillslopes using Flux-concentration relation and time compression approximation

    Science.gov (United States)

    Wang, Jie; Chen, Li; Yu, Zhongbo

    2018-02-01

    Rainfall infiltration on hillslopes is an important issue in hydrology, which is related to many environmental problems, such as flood, soil erosion, and nutrient and contaminant transport. This study aimed to improve the quantification of infiltration on hillslopes under both steady and unsteady rainfalls. Starting from Darcy's law, an analytical integral infiltrability equation was derived for hillslope infiltration by use of the flux-concentration relation. Based on this equation, a simple scaling relation linking the infiltration times on hillslopes and horizontal planes was obtained which is applicable for both small and large times and can be used to simplify the solution procedure of hillslope infiltration. The infiltrability equation also improved the estimation of ponding time for infiltration under rainfall conditions. For infiltration after ponding, the time compression approximation (TCA) was applied together with the infiltrability equation. To improve the computational efficiency, the analytical integral infiltrability equation was approximated with a two-term power-like function by nonlinear regression. Procedures of applying this approach to both steady and unsteady rainfall conditions were proposed. To evaluate the performance of the new approach, it was compared with the Green-Ampt model for sloping surfaces by Chen and Young (2006) and Richards' equation. The proposed model outperformed the sloping Green-Ampt, and both ponding time and infiltration predictions agreed well with the solutions of Richards' equation for various soil textures, slope angles, initial water contents, and rainfall intensities for both steady and unsteady rainfalls.

  4. The Bonneville Power Administration new energy-efficient homes programs: Final environmental impact statement: Volume 1, Assessing indoor air quality options

    International Nuclear Information System (INIS)

    1988-03-01

    BPA has underway marketing and incentive programs to encourage the construction of new energy-efficient homes that comply with Model Conservation Standards (MCS) developed by the Northwest Power Planning Council. These homes are designed to have lower infiltration rates than current building practices provide, which is likely to contribute to increased levels of indoor air pollutants, and may adversely affect the health of occupants. BPA's current and past new homes programs maintained ventilation rates comparable to those found in current practice homes by requiring balanced mechanical ventilation. BPA now proposes to give builders and consumers more flexibility by increasing the options for protecting indoor air quality in its new homes programs. This proposal is the impetus for this Environmental Impact Statement (EIS), which was prepared for BPA by Pacific Northwest Laboratory. BPS is preparing this EIS to assess whether other techniques maintain indoor air quality comparable to that found in homes built using current practices. Although many pollutants are potentially of great concern, our analysis concentrates on radon and formaldehyde. It is based on measured concentrations of these pollutants and measured ventilation rates in current practice. Ventilation was measured using fan pressurization tests, which measure only air leakage, and perfluorocarbon tracer gas (PFT) tests, which account for ventilation from mechanical devices and occupant behavior in addition to air leakage. These tests yielded two different estimates. We used these data to estimate pollutant concentrations and lifetime cancer rates under three alternative actions. Under all of the alternatives, radon had a much greater effect than formaldehyde. 102 refs

  5. [Soil infiltration characteristics under main vegetation types in Anji County of Zhejiang Province].

    Science.gov (United States)

    Liu, Dao-Ping; Chen, San-Xiong; Zhang, Jin-Chi; Xie, Li; Jiang, Jiang

    2007-03-01

    The study on the soil infiltration under different main vegetation types in Anji County of Zhejiang Province showed that the characteristics of soil infiltration differed significantly with land use type, and the test eight vegetation types could be classified into four groups, based on soil infiltration capability. The first group, deciduous broadleaved forest, had the strongest soil infiltration capability, and the second group with a stronger soil infiltration capability was composed of grass, pine forest, shrub community and tea bush. Bamboo and evergreen broadleaved forest were classified into the third group with a relatively strong soil infiltration capability, while bare land belonged to the fourth group because of the bad soil structure and poorest soil infiltration capability. The comprehensive parameters of soil infiltration (alpha) and root (beta) were obtained by principal component analysis, and the regression model of alpha and beta could be described as alpha = 0. 1708ebeta -0. 3122. Soil infiltration capability was greatly affected by soil physical and chemical characteristics and root system. Fine roots (soil physical and chemical properties, and the increase of soil infiltration capability was closely related to the amount of the fine roots.

  6. Estimation of deep infiltration in unsaturated limestone environments using cave lidar and drip count data

    Science.gov (United States)

    Mahmud, K.; Mariethoz, G.; Baker, A.; Treble, P. C.; Markowska, M.; McGuire, E.

    2016-01-01

    Limestone aeolianites constitute karstic aquifers covering much of the western and southern Australian coastal fringe. They are a key groundwater resource for a range of industries such as winery and tourism, and provide important ecosystem services such as habitat for stygofauna. Moreover, recharge estimation is important for understanding the water cycle, for contaminant transport, for water management, and for stalagmite-based paleoclimate reconstructions. Caves offer a natural inception point to observe both the long-term groundwater recharge and the preferential movement of water through the unsaturated zone of such limestone. With the availability of automated drip rate logging systems and remote sensing techniques, it is now possible to deploy the combination of these methods for larger-scale studies of infiltration processes within a cave. In this study, we utilize a spatial survey of automated cave drip monitoring in two large chambers of Golgotha Cave, south-western Western Australia (SWWA), with the aim of better understanding infiltration water movement and the relationship between infiltration, stalactite morphology, and unsaturated zone recharge. By applying morphological analysis of ceiling features from Terrestrial LiDAR (T-LiDAR) data, coupled with drip time series and climate data from 2012 to 2014, we demonstrate the nature of the relationships between infiltration through fractures in the limestone and unsaturated zone recharge. Similarities between drip rate time series are interpreted in terms of flow patterns, cave chamber morphology, and lithology. Moreover, we develop a new technique to estimate recharge in large-scale caves, engaging flow classification to determine the cave ceiling area covered by each flow category and drip data for the entire observation period, to calculate the total volume of cave discharge. This new technique can be applied to other cave sites to identify highly focussed areas of recharge and can help to better

  7. On the behaviour of radon in indoor air

    International Nuclear Information System (INIS)

    Lehtimaeki, M.; Kivistoe, T.

    1983-01-01

    In this work the behaviour of radon in indoor air has been studied. A simple mathematical model is presented to describe the variations in radon concentration in case of a periodic ventilation. This model has been tested with the aid of long-term measurements in two office buildings, in a large shipyard hall, and in a dwelling. The variations predicted by the simple model were observed in all buildings studied. It seems even possible that if the mixing of radon in the building is effective, the radon measurements can be used in estimating the infiltration rates. The measurement in one of the office buildings, however, indicated that the mixing of radon in a many-storied building can be extremely incomplete. The measurements also indicate that the soil can be a very important source of radon. (orig.) [de

  8. Non-Rated Air Force Line Officer Attrition Rates Using Survival Analysis

    Science.gov (United States)

    2015-03-26

    Further complicating human resourcing, all Air Force members–enlisted and officer–start at entry-level. Personnel entering the Air Force inventory are...the system [8]. Chi-squared automatic interaction detection (CHAID) is an algorithm “to predict the response behaviour [sic] of individuals as...branches with the highest probability may require incentives to increase attrition. The branches could be defined by gender, career field, religion

  9. River water infiltration enhances denitrification efficiency in riparian groundwater.

    Science.gov (United States)

    Trauth, Nico; Musolff, Andreas; Knöller, Kay; Kaden, Ute S; Keller, Toralf; Werban, Ulrike; Fleckenstein, Jan H

    2018-03-01

    Nitrate contamination in ground- and surface water is a persistent problem in countries with intense agriculture. The transition zone between rivers and their riparian aquifers, where river water and groundwater interact, may play an important role in mediating nitrate exports, as it can facilitate intensive denitrification, which permanently removes nitrate from the aquatic system. However, the in-situ factors controlling riparian denitrification are not fully understood, as they are often strongly linked and their effects superimpose each other. In this study, we present the evaluation of hydrochemical and isotopic data from a 2-year sampling period of river water and groundwater in the riparian zone along a 3rd order river in Central Germany. Based on bi- and multivariate statistics (Spearman's rank correlation and partial least squares regression) we can show, that highest rates for oxygen consumption and denitrification in the riparian aquifer occur where the fraction of infiltrated river water and at the same time groundwater temperature, are high. River discharge and depth to groundwater are additional explanatory variables for those reaction rates, but of minor importance. Our data and analyses suggest that at locations in the riparian aquifer, which show significant river water infiltration, heterotrophic microbial reactions in the riparian zone may be fueled by bioavailable organic carbon derived from the river water. We conclude that interactions between rivers and riparian groundwater are likely to be a key control of nitrate removal and should be considered as a measure to mitigate high nitrate exports from agricultural catchments. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Analysis of infiltration through mill tailings using a bromide tracer

    International Nuclear Information System (INIS)

    Lewis, G.J.; Stephens, D.B.

    1985-01-01

    Infiltration of precipitation into tailings impoundments as a means of recharge to underlying materials is often considered insignificant, particularly in arid and semi-arid environments. A series of experiments was performed to investigate the behavior of infiltrated precipitation into tailing soils, by the use of a bromide tracer. A bromide tracer was applied to the surface of columns driven into the tailings to monitor downward advancement of tracer-laden water. Controlled laboratory experiments on the behavior of the bromide tracer under varying precipitation events and initial soil moisture contents were also conducted. Results indicate that a definite downward migration of infiltrated precipitation occurs, particularly with large magnitude precipitation events, and that, eventually, some fraction of the infiltrated precipitation may continue downward below the zone affected by evaporation. The use of an artificially applied bromide tracer to monitor depth of infiltration of precipitation is a simple, safe technique that can provide valuable information for long-term tailings management strategies at low cost

  11. Efficacy of lignocaine in gel and spray form during buccal infiltration anesthesia in children: a randomized clinical trial.

    Science.gov (United States)

    Sharma, Anshul; Suprabha, B S; Shenoy, Ramya; Rao, Arathi

    2014-11-01

    To compare the efficacy of 15% lignocaine spray and 8% lignocaine gel as a topical anesthetic, in reducing pain, during buccal infiltration in children. Forty-two patients aged between 7 and 12 years requiring restorative procedures/extraction/pulp therapy of primary/ permanent teeth in the maxillary arch, under buccal infiltration anesthesia were selected for the study. The participants were randomly allocated into 2 groups of 21 each. In group A, 8% lignocaine gel and in group B, 15% lignocaine spray was applied prior to buccal infiltration. Pain was assessed using Wong-Baker faces pain rating scale (WBFPRS) and faces legs activity cry and consolability (FLACC) painscale. Pearson's chi-square test revealed that there was no significant difference in the FLACC scores of the two groups (p = 0.54). Independent t-test demonstrated that there was no significant difference in Wong-Bakers faces pain score between the two agents (p = 0.07). There is no significant difference in the efficacy of 15% lignocaine spray and 8% lignocaine gel as a topical anesthetic in controlling pain during buccal infiltration anesthesia, in children.

  12. Infiltration in reclaimed mined land ameliorated with deep tillage treatments

    International Nuclear Information System (INIS)

    Chong, S.K.; Cowsert, P.T.

    1997-01-01

    Reclamation of mined land with heavy machinery can result in soil compaction, which increases soil bulk density and reduces porosity, water infiltrability, root elongation and crop productivity. This paper examines the effect on infiltration in reclaimed surface mined land of a deep tillage treatment, and the subsequent changes in infiltration after the amelioration. The experiment was conducted at the Horse Creek Mine near Conant, Ferry County, IL, USA

  13. Tracks FAQs: How Do I Link Asthma Rates And Air Quality Data?

    Centers for Disease Control (CDC) Podcasts

    2011-07-07

    In this podcast, CDC Tracking experts discuss how to linkasthma rates and air quality data. Do you have a question for our Tracking experts? Please e-mail questions to trackingsupport@cdc.gov.  Created: 7/7/2011 by National Center for Environmental Health, Division of Environmental Hazards and Health Effects, Environmental Health Tracking Branch.   Date Released: 7/7/2011.

  14. Managing the Drivers of Air Flow and Water Vapor Transport in Existing Single Family Homes (Revised)

    Energy Technology Data Exchange (ETDEWEB)

    Cummings, J.; Withers, C.; Martin, E.; Moyer, N.

    2012-10-01

    This document focuses on managing the driving forces which move air and moisture across the building envelope. While other previously published Measure Guidelines focus on elimination of air pathways, the ultimate goal of this Measure Guideline is to manage drivers which cause air flow and water vapor transport across the building envelope (and also within the home), control air infiltration, keep relative humidity (RH) within acceptable limits, avoid combustion safety problems, improve occupant comfort, and reduce house energy use.

  15. PACE-90 water and solute transport calculations for 0.01, 0.1, and 0. 5 mm/yr infiltration into Yucca Mountain

    International Nuclear Information System (INIS)

    Dykhuizen, R.C.; Eaton, R.R.; Hopkins, P.L.; Martinez, M.J.

    1991-12-01

    Numerical results are presented for the Performance Assessment Calculational Exercise (PACE-90). One- and two-dimensional water and solute transport are presented for steady infiltration into Yucca Mountain. Evenly distributed infiltration rates of 0.01, 0.1, and 0.5 mm/yr were considered. The calculations of solute transport show that significant amounts of radionuclides can reach the water table over 100,000 yr at the 0.5 mm/yr rate. For time periods less than 10,000 yr or infiltrations less than 0.1 mm/yr very little solute reaches the water table. The numerical simulations clearly demonstrate that multi-dimensional effects can result in significant decreases in the travel time of solute through the modeled domain. Dual continuum effects are shown to be negligible for the low steady state fluxes considered. However, material heterogeneities may cause local amplification of the flux level in multi-dimensional flows. These higher flux levels may then require modeling of a dual continuum porous medium

  16. Non-technical skills evaluation in the critical care air ambulance environment: introduction of an adapted rating instrument--an observational study.

    Science.gov (United States)

    Myers, Julia A; Powell, David M C; Psirides, Alex; Hathaway, Karyn; Aldington, Sarah; Haney, Michael F

    2016-03-08

    In the isolated and dynamic health-care setting of critical care air ambulance transport, the quality of clinical care is strongly influenced by non-technical skills such as anticipating, recognising and understanding, decision making, and teamwork. However there are no published reports identifying or applying a non-technical skills framework specific to an intensive care air ambulance setting. The objective of this study was to adapt and evaluate a non-technical skills rating framework for the air ambulance clinical environment. In the first phase of the project the anaesthetists' non-technical skills (ANTS) framework was adapted to the air ambulance setting, using data collected directly from clinician groups, published literature, and field observation. In the second phase experienced and inexperienced inter-hospital transport clinicians completed a simulated critical care air transport scenario, and their non-technical skills performance was independently rated by two blinded assessors. Observed and self-rated general clinical performance ratings were also collected. Rank-based statistical tests were used to examine differences in the performance of experienced and inexperienced clinicians, and relationships between different assessment approaches and assessors. The framework developed during phase one was referred to as an aeromedical non-technical skills framework, or AeroNOTS. During phase two 16 physicians from speciality training programmes in intensive care, emergency medicine and anaesthesia took part in the clinical simulation study. Clinicians with inter-hospital transport experience performed more highly than those without experience, according to both AeroNOTS non-technical skills ratings (p = 0.001) and general performance ratings (p = 0.003). Self-ratings did not distinguish experienced from inexperienced transport clinicians (p = 0.32